WorldWideScience

Sample records for non-ventilated bulk storage

  1. A physical model to predict climate dynamics in ventilated bulk-storage of agricultural produce

    NARCIS (Netherlands)

    Lukasse, L.J.S.; Kramer-Cuppen, de J.E.; Voort, van der A.J.

    2007-01-01

    This paper presents a physical model for predicting climate dynamics in ventilated bulk-storage of agricultural produce. A well-ordered model presentation was obtained by combining an object-oriented zonal decomposition with a process-oriented decomposition through matrix¿vector notation. The

  2. Climate control of a bulk storage room for foodstuffs

    NARCIS (Netherlands)

    Mourik, van S.; Zwart, H.; Keesman, K.J.

    2006-01-01

    A storage room contains a bulk of agricultural products, such as potatoes, onions, fruits, etcetera. The products produce heat due to respiration, see for example [1, 2]. A ventilator blows cooled air around to keep the products at a steady temperature and prevent spoilage. The aim is to design a

  3. Identification and characterisation of factors affecting losses in the large-scale, non-ventilated bulk storage of wood chips and development of best storage practices

    Energy Technology Data Exchange (ETDEWEB)

    Garstang, J.; Weekes, A.; Poulter, R.; Bartlett, D.

    2002-07-01

    The report describes the findings of a study to determine the factors affecting the commercial storage of wood chips for biomass power generation in the UK. The UK's first such plant in North Yorkshire uses a mixture of forestry residues and short rotation coppice (SRC) willow, where problems with the stored fuel highlighted the need to determine best storage practices. Two wood chip piles were built (one with willow chip and the other with wood chips from board leaf forestry residues) and monitored (moisture, temperature, chemical composition, spore numbers and species, heat and air flows, bulk density, etc). Local weather data was also obtained. Recommendations for future storage practices are made.

  4. Fungal volatiles associated with moldy grain in ventilated and non-ventilated bin-stored wheat.

    Science.gov (United States)

    Sinha, R N; Tuma, D; Abramson, D; Muir, W E

    1988-01-01

    The fungal odor compounds 3-methyl-1-butanol, 1-octen-3-ol and 3-octanone were monitored in nine experimental bins in Winnipeg, Manitoba containing a hard red spring wheat during the autumn, winter and summer seasons of 1984-85. Quality changes were associated with seed-borne microflora and moisture content in both ventilated and non-ventilated bins containing wheat of 15.6 and 18.2% initial moisture content. All three odor compounds occurred in considerably greater amounts in bulk wheat in non-ventilated than in ventilated bins, particularly in those with wheat having 18.2% moisture content. The presence of these compounds usually coincided with infection of the seeds by the fungi Alternaria alternata (Fr.) Keissler, Aspergillus repens DeBarry, A. versicolor (Vuill.) Tiraboschi, Penicillium crustosum Thom, P. oxalicum Currie and Thom, P. aurantiogriesum Dierckx, and P. citrinum Thom. High production of all three odor compounds in damp wheat stored in non-ventilated bins was associated with heavy fungal infection of the seeds and reduction in seed germinability. High initial moisture content of the harvested grain accelerated the production of all three fungal volatiles in non-ventilated bins.

  5. Performance of Portable Ventilators Following Storage at Temperature Extremes.

    Science.gov (United States)

    Blakeman, Thomas C; Rodriquez, Dario; Britton, Tyler J; Johannigman, Jay A; Petro, Michael C; Branson, Richard D

    2016-05-01

    In the current theater of operation, medical devices are often shipped and stored at ambient conditions. The effect of storage at hot and cold temperature extremes on ventilator performance is unknown. We evaluated three portable ventilators currently in use or being evaluated for use by the Department of Defense (731, Impact Instrumentation; T1, Hamilton Medical; and Revel, CareFusion) at temperature extremes in a laboratory setting. The ventilators were stored at temperatures of 60°C and -35°C for 24 hours and were allowed to acclimate to room temperature for 30 minutes before evaluation. The T1 required an extra 15 to 30 minutes of acclimation to room temperature before the ventilator would deliver breaths. All delivered tidal volumes at room temperature and after storage at temperature extremes were less than the ±10% American Society for Testing and Materials standard with the Revel. Delivered tidal volumes at the pediatric settings were less than the ±10% threshold after storage at both temperatures and at room temperature with the 731. Storage at extreme temperature affected the performance of the portable ventilators tested. This study showed that portable ventilators may need an hour or more of acclimation time at room temperature after storage at temperature extremes to operate as intended. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

  6. Monitoring of carbon monoxide in residences with bulk wood pellet storage in the Northeast United States.

    Science.gov (United States)

    Rossner, Alan; Jordan, Carolyn E; Wake, Cameron; Soto-Garcia, Lydia

    2017-10-01

    in homes allows for better designs for storage bins and ventilation for storage areas. Hence, uniform policies for stored wood pellets in homes, schools, and businesses can be framed to ensure occupant safety. Currently in New York State rebates for the installation of wood pellet boilers are only provided if the bulk pellet storage is outside of the home, yet states such as New Hampshire, Vermont, and Maine currently do not have these restrictions.

  7. Odor volatiles associated with microflora in damp ventilated and non-ventilated bin-stored bulk wheat.

    Science.gov (United States)

    Tuma, D; Sinha, R N; Muir, W E; Abramson, D

    1989-05-01

    Western hard red spring wheat, stored at 20 and 25% moisture contents for 10 months during 1985-86, was monitored for biotic and abiotic variables in 10 unheated bins in Winnipeg, Manitoba. The major odor volatiles identified were 3-methyl-1-butanol, 3-octanone and 1-octen-3-ol. The production of these volatiles was associated and correlated with microfloral infection. Ventilation, used for cooling and drying of grain, disrupted microfloral growth patterns and production of volatiles. The highest levels of 3-methyl-1-butanol occurred in 25% moisture content wheat infected with bacteria, Penicillium spp. and Fusarium spp. In non-ventilated (control) bins with 20% moisture content wheat, 3-methyl-1-butanol was correlated with infection by members of the Aspergillus glaucus group and bacteria. In control bins, 1-octen-3-ol production was correlated with infection of wheat of both moisture contents by Penicillium spp. The fungal species, isolated from damp bin-stored wheat and tested for production of odor volatiles on wheat substrate, included Alternaria alternata (Fr.) Keissler, Aspergillus repens (Corda) Saccardo, A. flavus Link ex Fries, A. versicolor (Vuill.) Tiraboschi, Penicillium chrysogenum Thom, P. cyclopium Westling, Fusarium moniliforme Sheldon, F. semitectum (Cooke) Sacc. In the laboratory, fungus-inoculated wheat produced 3-methyl-1-butanol; 3-octanone and 1-octen-3-ol were also produced, but less frequently. Two unidentified bacterial species isolated from damp wheat and inoculated on agar produced 3-methyl-1-butanol.

  8. Ventilation of carbon monoxide from a biomass pellet storage tank--a study of the effects of variation of temperature and cross-ventilation on the efficiency of natural ventilation.

    Science.gov (United States)

    Emhofer, Waltraud; Lichtenegger, Klaus; Haslinger, Walter; Hofbauer, Hermann; Schmutzer-Roseneder, Irene; Aigenbauer, Stefan; Lienhard, Martin

    2015-01-01

    Wood pellets have been reported to emit toxic gaseous emissions during transport and storage. Carbon monoxide (CO) emission, due to the high toxicity of the gas and the possibility of it being present at high levels, is the most imminent threat to be considered before entering a pellet storage facility. For small-scale (ventilation, preferably natural ventilation utilizing already existing openings, has become the most favored solution to overcome the problem of high CO concentrations. However, there is little knowledge on the ventilation rates that can be reached and thus on the effectiveness of such measures. The aim of the study was to investigate ventilation rates for a specific small-scale pellet storage system depending on characteristic temperature differences. Furthermore, the influence of the implementation of a chimney and the influence of cross-ventilation on the ventilation rates were investigated. The air exchange rates observed in the experiments ranged between close to zero and up to 8 m(3) h(-1), depending largely on the existing temperature differences and the existence of cross-ventilation. The results demonstrate that implementing natural ventilation is a possible measure to enhance safety from CO emissions, but not one without limitations. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  9. Bulk energy storage increases United States electricity system emissions.

    Science.gov (United States)

    Hittinger, Eric S; Azevedo, Inês M L

    2015-03-03

    Bulk energy storage is generally considered an important contributor for the transition toward a more flexible and sustainable electricity system. Although economically valuable, storage is not fundamentally a "green" technology, leading to reductions in emissions. We model the economic and emissions effects of bulk energy storage providing an energy arbitrage service. We calculate the profits under two scenarios (perfect and imperfect information about future electricity prices), and estimate the effect of bulk storage on net emissions of CO2, SO2, and NOx for 20 eGRID subregions in the United States. We find that net system CO2 emissions resulting from storage operation are nontrivial when compared to the emissions from electricity generation, ranging from 104 to 407 kg/MWh of delivered energy depending on location, storage operation mode, and assumptions regarding carbon intensity. Net NOx emissions range from -0.16 (i.e., producing net savings) to 0.49 kg/MWh, and are generally small when compared to average generation-related emissions. Net SO2 emissions from storage operation range from -0.01 to 1.7 kg/MWh, depending on location and storage operation mode.

  10. 33 CFR 127.313 - Bulk storage.

    Science.gov (United States)

    2010-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas Operations § 127.313 Bulk storage. (a) The operator...: (1) LNG. (2) LPG. (3) Vessel fuel. (4) Oily waste from vessels. (5) Solvents, lubricants, paints, and...

  11. 27 CFR 19.342 - Receipt and storage of bulk spirits and wines.

    Science.gov (United States)

    2010-04-01

    ... bulk spirits and wines. 19.342 Section 19.342 Alcohol, Tobacco Products and Firearms ALCOHOL AND... Receipt and storage of bulk spirits and wines. (a) Deposit. All spirits entered for deposit in the storage... spirits or wines are being deposited in a partially filled tank in storage on bonded premises...

  12. Bulk Fuel Storage and Delivery Systems Infrastructure Military Construction Requirements for Japan

    National Research Council Canada - National Science Library

    Padgett, Gary

    2000-01-01

    .... Specifically, this audit evaluated requirements for bulk fuel storage facilities at three locations in Japan. We also evaluated the management control program as it relates to the bulk fuel storage military construction requirements validation process.

  13. Characterization and assessment of novel bulk storage technologies : a study for the DOE Energy Storage Systems program.

    Energy Technology Data Exchange (ETDEWEB)

    Huff, Georgianne; Tong, Nellie (KEMA Consulting, Fairfax, VA); Fioravanti, Richard (KEMA Consulting, Fairfax, VA); Gordon, Paul (Sentech/SRA International, Bethesda, MD); Markel, Larry (Sentech/SRA International, Bethesda, MD); Agrawal, Poonum (Sentech/SRA International, Bethesda, MD); Nourai, Ali (KEMA Consulting, Fairfax, VA)

    2011-04-01

    This paper reports the results of a high-level study to assess the technological readiness and technical and economic feasibility of 17 novel bulk energy storage technologies. The novel technologies assessed were variations of either pumped storage hydropower (PSH) or compressed air energy storage (CAES). The report also identifies major technological gaps and barriers to the commercialization of each technology. Recommendations as to where future R&D efforts for the various technologies are also provided based on each technology's technological readiness and the expected time to commercialization (short, medium, or long term). The U.S. Department of Energy (DOE) commissioned this assessment of novel concepts in large-scale energy storage to aid in future program planning of its Energy Storage Program. The intent of the study is to determine if any new but still unproven bulk energy storage concepts merit government support to investigate their technical and economic feasibility or to speed their commercialization. The study focuses on compressed air energy storage (CAES) and pumped storage hydropower (PSH). It identifies relevant applications for bulk storage, defines the associated technical requirements, characterizes and assesses the feasibility of the proposed new concepts to address these requirements, identifies gaps and barriers, and recommends the type of government support and research and development (R&D) needed to accelerate the commercialization of these technologies.

  14. [A comparison of leak compensation in six acute care ventilators during non-invasive ventilation].

    Science.gov (United States)

    Hu, X S; Wang, Y; Wang, Z T; Yan, P; Zhang, X G; Zhao, S F; Xie, F; Gu, H J; Xie, L X

    2017-02-12

    Objective: To compare the ability of leak compensation in 6 medical ventilators during non-invasive ventilation. Methods: Six medical ventilators were selected, including 3 non-invasive ventilators (V60, Flexo and Stellar150), and 3 invasive ventilators(Avea, Servo I and BellaVist). Using a lung simulator, the ability of leak compensation was evaluated during triggering and cycling in 2 respiratory mechanics conditions (high airway resistance condition and high elastance resistance condition), and each condition was performed under 2 PEEP levels (4, and 8 cmH(2)O, 1 mmHg=0.098 kPa) at 4 air leak level conditions (L0: 2-3 L/min, L1: 8-10 L/min, L2: 22-27 L/min, L3: 35-40 L/min). Results: In the high elastance resistance condition (L2, L3)with different leak levels, the number of auto-triggering and miss-triggering of the non-invasive ventilator Flexo was significantly less than those of the others (L2: 1, 1; L3: 1.67, 1.33, P ventilators ( P ventilators (1, 0.67, 0, P ventilators in both high airway resistance and high elastance resistance conditions with L0 and L1 leak levels and PEEP levels [ARDS, PEEP=4: (109.8±1.8) ms, (112.0±0.6) ms; ARDS, PEEP=8: (103.1±0.7) ms, (109.7±0.7) ms; COPD, PEEP=4: (207.3±1.1) ms, (220.8±1.1) ms; COPD, PEEP=8: (195.6±6.7) ms, (200.0±1.2) ms , P ventilators could be synchronized, among which V60, Stellar150 and Flexo presented a good performance features in specific conditions.

  15. Assessment of ventilation system for centralized storage of spent radiation sources

    International Nuclear Information System (INIS)

    Soroka, Yu.N.; Udod, E.V.

    2014-01-01

    The hazards associated with treatment spent radiation sources in the centralized storage facility under construction in the Chernobyl exclusion zone are analysis. Models are proposed to calculate possible situations of contamination with radionuclides in centralized storage rooms. The required ventilation rate is calculated for areas where sources containing 60 Co; 90 Sr, 137 Cs, 226 Ra, 238 Pu, 239 Pu and 241 Am radionuclides are supposed to be treated

  16. Ventilation and air conditioning system in waste treatment and storage facilities

    International Nuclear Information System (INIS)

    Kinoshita, Hirotsugu; Sugawara, Kazushige.

    1987-01-01

    So far, the measures concerning the facilities for treating and storing radioactive wastes in nuclear fuel cycle in Japan were in the state which cannot be said to be sufficient. In order to cope with this situation, electric power companies constructed and operated radioactive waste concentration and volume reduction facilities, solid waste storing facilities for drums, high level solid waste storing facilities, spent fuel cask preserving facilities and so on successively in the premises of nuclear power stations, and for the wastes expected in future, the research and the construction plan of the facilities for treating and storing low, medium and high level wastes have been advanced. The ventilation and air conditioning system for these facilities is the important auxiliary system which has the mission of maintaining safe and pleasant environment in the facilities and lowering as far as possible the release of radioactive substances to outside. The outline of waste treatment and storage facilities is explained. The design condition, ventilation and air conditioning method, the features of respective waste treatment and storage facilities, and the problems for the future are described. Hereafter, mechanical ventilation system continues to be the main system, and filters become waste, while the exchange of filters is accompanied by the radiation exposure of workers. (Kako, I.)

  17. Application of PCM energy storage in combination with night ventilation for space cooling

    International Nuclear Information System (INIS)

    Barzin, Reza; Chen, John J.J.; Young, Brent R.; Farid, Mohammed M.

    2015-01-01

    Highlights: • Night ventilation were tested in combination with PCM-impregnated gypsum boards. • The Price-based method were experimentally used to perform peak load shifting. • Importance of the application of a smart control were experimentally investigated. • A cost and energy saving up to 93% and 92% per day respectively were achieved. - Abstract: In recent years, as a result of the continuous increase in energy demand, the use of energy storage has become increasingly important. To address this problem, the application of phase change materials (PCM) in buildings has received attention because of their high energy storage density and their ease of incorporation in building envelopes. Despite large experimental works conducted on the application phase change materials in buildings, there is very little work done on this application in combination with night ventilation. In this study, the application of night ventilation in combination with PCM-impregnated gypsum boards for cooling purposes was experimentally investigated. Two identical test huts equipped with “smart” control systems were used for testing the concept. One hut was constructed using impregnated gypsum boards, while the other hut was finished with ordinary gypsum board. Initially an air conditioning (AC) unit, without night ventilation, was used in both huts to charge the PCM during low peak period, showing very little savings in electricity. However, when night ventilation was used to charge the PCM instead, a weekly electricity saving of 73% was achieved.

  18. Large temporal scale and capacity subsurface bulk energy storage with CO2

    Science.gov (United States)

    Saar, M. O.; Fleming, M. R.; Adams, B. M.; Ogland-Hand, J.; Nelson, E. S.; Randolph, J.; Sioshansi, R.; Kuehn, T. H.; Buscheck, T. A.; Bielicki, J. M.

    2017-12-01

    Decarbonizing energy systems by increasing the penetration of variable renewable energy (VRE) technologies requires efficient and short- to long-term energy storage. Very large amounts of energy can be stored in the subsurface as heat and/or pressure energy in order to provide both short- and long-term (seasonal) storage, depending on the implementation. This energy storage approach can be quite efficient, especially where geothermal energy is naturally added to the system. Here, we present subsurface heat and/or pressure energy storage with supercritical carbon dioxide (CO2) and discuss the system's efficiency, deployment options, as well as its advantages and disadvantages, compared to several other energy storage options. CO2-based subsurface bulk energy storage has the potential to be particularly efficient and large-scale, both temporally (i.e., seasonal) and spatially. The latter refers to the amount of energy that can be stored underground, using CO2, at a geologically conducive location, potentially enabling storing excess power from a substantial portion of the power grid. The implication is that it would be possible to employ centralized energy storage for (a substantial part of) the power grid, where the geology enables CO2-based bulk subsurface energy storage, whereas the VRE technologies (solar, wind) are located on that same power grid, where (solar, wind) conditions are ideal. However, this may require reinforcing the power grid's transmission lines in certain parts of the grid to enable high-load power transmission from/to a few locations.

  19. Bulk Fuel Storage and Delivery Systems Infrastructure Military Construction Requirements for Japan

    National Research Council Canada - National Science Library

    Padgett, Gary

    2000-01-01

    This report is one in a series that addresses the accuracy and reliability of maintenance, repair, and environmental and construction requirements for bulk fuel storage and delivery systems infrastructure...

  20. Non-invasive mechanical ventilation with spinal anesthesia for cesarean delivery.

    Science.gov (United States)

    Erdogan, G; Okyay, D Z; Yurtlu, S; Hanci, V; Ayoglu, H; Koksal, B; Turan, I O

    2010-10-01

    We present the successful use of perioperative non-invasive mechanical ventilation in a morbidly obese pregnant woman with bronchial asthma, severe preeclampsia and pulmonary edema undergoing an emergency cesarean delivery with spinal anesthesia. The combination of non-invasive mechanical ventilation with neuraxial anesthesia may be of value in selected parturients with acute or chronic respiratory insufficiency requiring surgery. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Non-invasive ventilation after surgery in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Olivieri, C; Castioni, C A; Livigni, S; Bersano, E; Cantello, R; Della Corte, F; Mazzini, L

    2014-04-01

    Surgery in patients affected by amyotrophic lateral sclerosis (ALS) presents a particular anesthetic challenge because of the risk of post-operative pulmonary complications. We report on the use of non-invasive ventilation (NIV) to prevent post-operative pulmonary complications (PPCs) in nine patients affected by ALS enrolled in a phase-1 clinical trial with stem cell transplantation. All patients were treated with autologous mesenchymal stem cells implanted into the spinal cord with a surgical procedure. Anesthesia was induced with propofol and maintained with remifentanil and sevoflurane. No muscle relaxant was used. After awakening and regain of spontaneous breathing, patients were tracheally extubated. Non-invasive ventilation through nasal mask was delivered and non-invasive positive pressure ventilation and continuous positive pressure ventilation were started. The average time on NIV after surgery was 3 h and 12 min. All patients regained stable spontaneous breathing after NIV discontinuation and had no episodes of respiratory failure until the following day. Our case series suggest that the use of NIV after surgery can be a safe strategy to prevent PPCs in patients affected by ALS. The perioperative procedure we chose for these patients appeared safe even in patients with advanced functional stage of the disease. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Non-Invasive Mechanic Ventilation Using in Flail Chest, Caused By Blunt Chest Trauma

    Directory of Open Access Journals (Sweden)

    Serdar Onat

    2008-01-01

    Full Text Available A 75-year-old woman admitted our faculty emergency room with shortness of breath, and chest pain after traffic accident’s second hour. She was diagnosed as bilateral multipl rib fractures, left clavicula fracture, and left flail chest by phsical and radiological examinations. She was transfered to Chest Surgery Depatment’s intensive care unit. The patient was undergone non-invasive mask mechanic ventilation support, because of the decreasing of blood oxygen saturation and increasing of arteriel blood partial carbondioxide pressure. The treatment of non-invasive mechanic ventilation was succesfull for ventilation support. With this report, we would like to attentioned that non-invasive mechanic ventilation for blunt chest trauma patients could be used succesfully and could be used instead of endotracheal invasive mechanic ventilation.

  3. Clinical efficacy of Myozyme on one ventilator dependent patient with late-onset glycogen storage disease typeⅡ

    Directory of Open Access Journals (Sweden)

    Juan YANG

    2014-05-01

    Full Text Available Objective To evaluate the effect of Myozyme on one ventilator dependent patient with late-onset glycogen storage disease typeⅡ (GSDⅡ.  Methods Myozyme infusion was administered based on manufacturer's recommendations at 20 mg/kg every 2 to 4 weeks, beginning at actual body weight, and was continuously treated for 6 times. No premedication was performed except 5 mg dexamethasone was administered at the first use of Myozyme. Clinical assessment was completed every day and was lasted for 16 months including motor function, the time free of ventilation, and the change of respiration parameters.  Results Myozyme was well tolerated without adverse reactions. Pain on shoulder began to alleviate the next day after taking Myozyme. With the prolonged time and increased number of taking drugs, the time free of ventilation and doing in-situ stepping prolonged, and the speed of stepping in-situ also increased. Besides, the strength of lifting the upper limbs increased, and both the time and speed of walking free of ventilation prolonged. The maximus curative effect occured at the 7th month (3 months after drug withdrawal after treatment and returned to pre-treatment levels at the 8th month (4 months after drug withdrawal. The pain on shoulder was the first symptom that got improved, and the fastest symptom that returned to baseline.  Conclusions Myozyme has positive effect on ventilated patients with late-onset glycogen storage disease type Ⅱ. doi: 10.3969/j.issn.1672-6731.2014.05.009

  4. Predictors of need for noninvasive ventilation during respiratory tract infections in medically stable, non-ventilated subjects with amyotrophic lateral sclerosis.

    Science.gov (United States)

    Sancho, Jesus; Servera, Emilio; Bañuls, Pilar; Marin, Julio

    2015-04-01

    Acute lower respiratory infections can impair muscle strength in patients with amyotrophic lateral sclerosis (ALS). When associated with an increase in load on the respiratory system, this situation may precipitate hypercapnic respiratory failure in non-ventilated patients with ALS. The aim of this study was to determine whether a clinical or functional parameter can predict the need for noninvasive ventilation (NIV) during an acute respiratory infection for medically stable, non-ventilated patients with ALS. This was a prospective study involving all non-ventilated subjects with ALS admitted due to an acute respiratory infection to a respiratory care unit from a tertiary hospital. Thirty-two non-ventilated subjects with ALS were admitted to our respiratory care unit due to an acute respiratory infection: 60.72 ± 10.54 y, 13 males, 23 with spinal onset, FVC of 1.58 ± 0.83 L, FVC of 56.21 ± 23.15% of predicted, peak cough flow of 3.41 ± 1.77 L/s, maximum insufflation capacity of 1.87 ± 0.94 L, revised Amyotrophic Lateral Sclerosis Functional Rating Scale score of 22.80 ± 8.83, and Norris bulbar score of 23.48 ± 12.14. Fifteen subjects required NIV during the episode. Logistic regression analysis showed that the only predictors of need for NIV were percent-of-predicted FVC (odds ratio of 1.06, 95% CI 1.01-1.11, P = .02) and peak cough flow (odds ratio of 2.57, 95% CI 1.18-5.59, P = .02). In medically stable, non-ventilated patients with ALS, measurement of percent-of-predicted FVC and peak cough flow can predict the need for NIV during an acute lower respiratory tract infection. Copyright © 2015 by Daedalus Enterprises.

  5. Secondary containment systems for bulk oil storage facilities

    International Nuclear Information System (INIS)

    Carr, B.A.

    1996-01-01

    The United States Environmental Protection Agency has conducted site inspections at several onshore bulk oil above ground storage facilities, to ensure that owners follow the spill prevention, control and countermeasure regulations. The four violations which were most frequently cited at these facilities were: (1) lack of a spill prevention plan, (2) lack of appropriate containment equipment to prevent discharged oil from reaching a navigable water course, (3) inadequate secondary containment structures, and (4) lack of an adequate quick drainage system in the facility tank loading/unloading area. Suggestions for feasible designs which would improve the impermeability of secondary containment for above ground storage tanks (AST) included the addition of a liner, retrofitting the bottom of an AST with a second steel plate, using a geosynthetic liner on top of the original bottom, installing a leak detection system in the interstitial space between the steel plates, or installing an under-tank liner with a leak detection system during construction of a new AST. 2 refs

  6. Development of a computer code to predict a ventilation requirement for an underground radioactive waste storage tank

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y.J.; Dalpiaz, E.L. [ICF Kaiser Hanford Co., Richland, WA (United States)

    1997-08-01

    Computer code, WTVFE (Waste Tank Ventilation Flow Evaluation), has been developed to evaluate the ventilation requirement for an underground storage tank for radioactive waste. Heat generated by the radioactive waste and mixing pumps in the tank is removed mainly through the ventilation system. The heat removal process by the ventilation system includes the evaporation of water from the waste and the heat transfer by natural convection from the waste surface. Also, a portion of the heat will be removed through the soil and the air circulating through the gap between the primary and secondary tanks. The heat loss caused by evaporation is modeled based on recent evaporation test results by the Westinghouse Hanford Company using a simulated small scale waste tank. Other heat transfer phenomena are evaluated based on well established conduction and convection heat transfer relationships. 10 refs., 3 tabs.

  7. Bulk Fuel Storage Requirements for Maintenance, Repair, and Environmental Projects at Fort Hood, Texas

    National Research Council Canada - National Science Library

    Carros, Deborah

    2000-01-01

    This report is one in a series that addresses the accuracy and reliability of maintenance, repair, environmental, and construction requirements for bulk fuel storage and delivery systems infrastructure...

  8. 40 CFR 63.11087 - What requirements must I meet for gasoline storage tanks if my facility is a bulk gasoline...

    Science.gov (United States)

    2010-07-01

    ... gasoline storage tanks if my facility is a bulk gasoline terminal, pipeline breakout station, or pipeline... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Source Category: Gasoline... § 63.11087 What requirements must I meet for gasoline storage tanks if my facility is a bulk gasoline...

  9. Non-invasive ventilation with neurally adjusted ventilatory assist in newborns.

    Science.gov (United States)

    Stein, Howard; Beck, Jennifer; Dunn, Michael

    2016-06-01

    Neurally adjusted ventilatory assist (NAVA) is a mode of ventilation in which both the timing and degree of ventilatory assist are controlled by the patient. Since NAVA uses the diaphragm electrical activity (Edi) as the controller signal, it is possible to deliver synchronized non-invasive NAVA (NIV-NAVA) regardless of leaks and to monitor continuously patient respiratory pattern and drive. Advantages of NIV-NAVA over conventional modes include improved patient-ventilator interaction, reliable respiratory monitoring and self-regulation of respiratory support. In theory, these characteristics make NIV-NAVA an ideal mode to provide effective, appropriate non-invasive support to newborns with respiratory insufficiency. NIV-NAVA has been successfully used clinically in neonates as a mode of ventilation to prevent intubation, to allow early extubation, and as a novel way to deliver nasal continuous positive airway pressure. The use of NAVA in neonates is described with an emphasis on studies and clinical experience with NIV-NAVA. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Mechanical ventilation system: General. 154.1200 Section... CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a...

  11. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Mechanical ventilation system: Standards. 154.1205... CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a...

  12. Position paper - primary ventilation system configuration

    International Nuclear Information System (INIS)

    Dalpiaz, E.L.

    1994-06-01

    The purpose of this paper is to develop and document a position on the configuration of the primary ventilation system. This configuration will be used on the waste storage tanks currently being designed for the Multi-Function Waste Tank Facility. The primary ventilation system provides a single treatment train and exhaust fan for each waste storage tank. The ventilation systems from each of two tanks are grouped with an additional treatment train and exhaust fan that function as backup to either of the two systems

  13. British Thoracic Society Quality Standards for acute non-invasive ventilation in adults

    Science.gov (United States)

    Davies, Michael; Allen, Martin; Bentley, Andrew; Bourke, Stephen C; Creagh-Brown, Ben; D’Oliveiro, Rachel; Glossop, Alastair; Gray, Alasdair; Jacobs, Phillip; Mahadeva, Ravi; Moses, Rachael; Setchfield, Ian

    2018-01-01

    Introduction The purpose of the quality standards document is to provide healthcare professionals, commissioners, service providers and patients with a guide to standards of care that should be met for the provision of acute non-invasive ventilation in adults together with measurable markers of good practice. Methods Development of British Thoracic Society (BTS) Quality Standards follows the BTS process of quality standard production based on the National Institute for Health and Care Excellence process manual for the development of quality standards. Results 6 quality statements have been developed, each describing a standard of care for the provision of acute non-invasive ventilation in the UK, together with measurable markers of good practice. Conclusion BTS Quality Standards for acute non-invasive ventilation in adults form a key part of the range of supporting materials that the Society produces to assist in the dissemination and implementation of guideline’s recommendations. PMID:29636979

  14. Non-invasive mechanical ventilation and mortality in elderly immunocompromised patients hospitalized with pneumonia: a retrospective cohort study.

    Science.gov (United States)

    Johnson, Christopher S; Frei, Christopher R; Metersky, Mark L; Anzueto, Antonio R; Mortensen, Eric M

    2014-01-27

    Mortality after pneumonia in immunocompromised patients is higher than for immunocompetent patients. The use of non-invasive mechanical ventilation for patients with severe pneumonia may provide beneficial outcomes while circumventing potential complications associated with invasive mechanical ventilation. The aim of our study was to determine if the use of non-invasive mechanical ventilation in elderly immunocompromised patients with pneumonia is associated with higher all-cause mortality. In this retrospective cohort study, data were obtained from the Department of Veterans Affairs administrative databases. We included veterans age ≥65 years who were immunocompromised and hospitalized due to pneumonia. Multilevel logistic regression analysis was used to determine the relationship between the use of invasive versus non-invasive mechanical ventilation and 30-day and 90-day mortality. Of 1,946 patients in our cohort, 717 received non-invasive mechanical ventilation and 1,229 received invasive mechanical ventilation. There was no significant association between all-cause 30-day mortality and non-invasive versus invasive mechanical ventilation in our adjusted model (odds ratio (OR) 0.85, 95% confidence interval (CI) 0.66-1.10). However, those patients who received non-invasive mechanical ventilation had decreased 90-day mortality (OR 0.66, 95% CI 0.52-0.84). Additionally, receipt of guideline-concordant antibiotics in our immunocompromised cohort was significantly associated with decreased odds of 30-day mortality (OR 0.31, 95% CI 0.24-0.39) and 90-day mortality (OR 0.41, 95% CI 0.31-0.53). Our findings suggest that physicians should consider the use of non-invasive mechanical ventilation, when appropriate, for elderly immunocompromised patients hospitalized with pneumonia.

  15. An Investigation into the Non-bulk Rail Freight Transport in Australia

    Directory of Open Access Journals (Sweden)

    Hadi Ghaderi

    2015-03-01

    Full Text Available In the last decade freight transport has gained further momentum in Australia, partly through significant demand growth at both domestic and international levels and partly as the result of Australia's long term need for infrastructure decision making. Amongst the freight task, non-bulk freight is the fastest growing freight task in Australia and is forecast to grow much faster than the rate of population growth and the average national GDP growth. However, rail's share in the non-bulk market has declined significantly in the last four decades. This study therefore provides an insight into the efficiency and operational management issues facing by the Australian non-bulk rail sector by focusing on three areas; the level of track compatibility and the relevant operational issues, the demographics of non-bulk freight in Australia and the current status of intermodal terminals in relation to rail connectivity and location. As the result, a more detailed understanding of the current shortages in the Australian non-bulk rail freight sector is achieved and managerial implications are provided.

  16. Ventilator respiratory graphic diagnosis of hiccupping in non-ketotic hyperglycinaemia.

    Science.gov (United States)

    Panayiotou, Eliana; Spike, Kelly; Morley, Colin; Belteki, Gusztav

    2017-08-09

    A neonate presented with early encephalopathy deteriorated and was intubated and ventilated. Ventilator data were monitored and recorded at 100 Hz for 24 hours.The infant had many sudden deep inspirations during this time which were initially thought to be seizures. These were characterised by short, rapid, large inspirations when the airway pressure was reduced well below the positive end expiratory pressure level. Analysis of the ventilator data showed that these were hiccupping episodes misinterpreted by the ventilator as spontaneous breaths and triggering ventilator inflations. The expired tidal volumes during the hiccupping episodes were more than double the set 4.5 mL/kg. During these episodes, there was no change in the level of consciousness or in the amplitude-integrated electroencephalogram signal. Detailed respiratory recording of pathological hiccups has not been reported.Metabolic screening diagnosed non-ketotic hyperglycinaemia. Hiccups commonly occur in this condition and should not be misinterpreted as seizures, spontaneous breaths or gasps. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  17. Calibration of Mine Ventilation Network Models Using the Non-Linear Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Guang Xu

    2017-12-01

    Full Text Available Effective ventilation planning is vital to underground mining. To ensure stable operation of the ventilation system and to avoid airflow disorder, mine ventilation network (MVN models have been widely used in simulating and optimizing the mine ventilation system. However, one of the challenges for MVN model simulation is that the simulated airflow distribution results do not match the measured data. To solve this problem, a simple and effective calibration method is proposed based on the non-linear optimization algorithm. The calibrated model not only makes simulated airflow distribution results in accordance with the on-site measured data, but also controls the errors of other parameters within a minimum range. The proposed method was then applied to calibrate an MVN model in a real case, which is built based on ventilation survey results and Ventsim software. Finally, airflow simulation experiments are carried out respectively using data before and after calibration, whose results were compared and analyzed. This showed that the simulated airflows in the calibrated model agreed much better to the ventilation survey data, which verifies the effectiveness of calibrating method.

  18. Bulk-mediated surface diffusion: non-Markovian desorption dynamics

    International Nuclear Information System (INIS)

    Revelli, Jorge A; Budde, Carlos E; Prato, Domingo; Wio, Horacio S

    2005-01-01

    Here we analyse the dynamics of adsorbed molecules within the bulk-mediated surface diffusion framework, when the particle's desorption mechanism is characterized by a non-Markovian process, while the particle's adsorption as well as its motion in the bulk is governed by Markovian dynamics. We study the diffusion of particles in both semi-infinite and finite cubic lattices, analysing the conditional probability to find the system on the reference absorptive plane as well as the surface dispersion as functions of time. The results are compared with known Markovian cases showing the differences that can be exploited to distinguish between Markovian and non-Markovian desorption mechanisms in experimental situations

  19. Initial mechanical ventilator settings and lung protective ventilation in the ED.

    Science.gov (United States)

    Wilcox, Susan R; Richards, Jeremy B; Fisher, Daniel F; Sankoff, Jeffrey; Seigel, Todd A

    2016-08-01

    Mechanical ventilation with low tidal volumes has been shown to improve outcomes for patients both with and without acute respiratory distress syndrome. This study aims to characterize mechanically ventilated patients in the emergency department (ED), describe the initial ED ventilator settings, and assess for associations between lung protective ventilation strategies in the ED and outcomes. This was a multicenter, prospective, observational study of mechanical ventilation at 3 academic EDs. We defined lung protective ventilation as a tidal volume of less than or equal to 8 mL/kg of predicted body weight and compared outcomes for patients ventilated with lung protective vs non-lung protective ventilation, including inhospital mortality, ventilator days, intensive care unit length of stay, and hospital length of stay. Data from 433 patients were analyzed. Altered mental status without respiratory pathology was the most common reason for intubation, followed by trauma and respiratory failure. Two hundred sixty-one patients (60.3%) received lung protective ventilation, but most patients were ventilated with a low positive end-expiratory pressure, high fraction of inspired oxygen strategy. Patients were ventilated in the ED for a mean of 5 hours and 7 minutes but had few ventilator adjustments. Outcomes were not significantly different between patients receiving lung protective vs non-lung protective ventilation. Nearly 40% of ED patients were ventilated with non-lung protective ventilation as well as with low positive end-expiratory pressure and high fraction of inspired oxygen. Despite a mean ED ventilation time of more than 5 hours, few patients had adjustments made to their ventilators. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. NDE to Manage Atmospheric SCC in Canisters for Dry Storage of Spent Fuel: An Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Ryan M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pardini, Allan F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cuta, Judith M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Adkins, Harold E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Andrew M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qiao, Hong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Larche, Michael R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Diaz, Aaron A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Doctor, Steven R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-09-01

    This report documents efforts to assess representative horizontal (Transuclear NUHOMS®) and vertical (Holtec HI-STORM) storage systems for the implementation of non-destructive examination (NDE) methods or techniques to manage atmospheric stress corrosion cracking (SCC) in canisters for dry storage of used nuclear fuel. The assessment is conducted by assessing accessibility and deployment, environmental compatibility, and applicability of NDE methods. A recommendation of this assessment is to focus on bulk ultrasonic and eddy current techniques for direct canister monitoring of atmospheric SCC. This assessment also highlights canister regions that may be most vulnerable to atmospheric SCC to guide the use of bulk ultrasonic and eddy current examinations. An assessment of accessibility also identifies canister regions that are easiest and more difficult to access through the ventilation paths of the concrete shielding modules. A conceivable sampling strategy for canister inspections is to sample only the easiest to access portions of vulnerable regions. There are aspects to performing an NDE inspection of dry canister storage system (DCSS) canisters for atmospheric SCC that have not been addressed in previous performance studies. These aspects provide the basis for recommendations of future efforts to determine the capability and performance of eddy current and bulk ultrasonic examinations for atmospheric SCC in DCSS canisters. Finally, other important areas of investigation are identified including the development of instrumented surveillance specimens to identify when conditions are conducive for atmospheric SCC, characterization of atmospheric SCC morphology, and an assessment of air flow patterns over canister surfaces and their influence on chloride deposition.

  1. Active space cooling with night-coldness - development of a decentralized ventilation system with latent heat storage; Aktive Raumkuehlung mit Nachkaelte - Entwicklung eines dezentralen Lueftungsgeraetes mit Latentwaermespeicher. Imtech-Haus, Hamburg Referenzanlage

    Energy Technology Data Exchange (ETDEWEB)

    Luedemann, B.; Detzer, R. [Imtech Deutschland, Hamburg (Germany)

    2007-04-15

    Imtech Germany a decentralized ventilation system with a latent heat-storage unit made of Phase Change Material. The equipment was used successfully in a first reference asset in the Imtech house in Hamburg. During the day active space cooling is realized by storage of night-cold. In combination with a night ventilation the attached areas could be held continuous within the comfort range under 26 C under normal summer conditions. The decentralized ventilation system including control is developed to series production readiness and will be introduced now on the market. (orig.)

  2. Sleep-related breathing disorders and non-invasive ventilation

    Directory of Open Access Journals (Sweden)

    Agata Lax

    2015-05-01

    Full Text Available Non-invasive mechanical ventilation (NPPV was originally used in patients with acute respiratory impairment or exacerbations of chronic respiratory diseases, as an alternative to the endotracheal tube. Over the last thirty years NPPV has been also used at night in patients with stable chronic lung disease such as obstructive sleep apnea, the overlap syndrome (chronic obstructive pulmonary disease and obstructive sleep apnea, neuromuscular disorders, obesity-hypoventilation syndrome, and in other conditions such as sleep disorders associated with congestive heart failure (Cheyne-Stokes respiration. In this no-systematic review we discuss the different types of NPPV, the specific conditions in which they can be used and the indications, recommendations and evidence supporting the efficacy of NPPV. Optimizing patient acceptance and adherence to non-invasive ventilation treatment is challenging. The treatment of sleep-related disorders is a life-threatening condition. The optimal level of treatment should be determined in a sleep laboratory. Side effects directly affecting the patient’s adherence to treatment are known. The most common are nasopharyngeal symptoms including increased congestion and rhinorrhea; these effects are related to reduced humidity of inspired gas. Humidification of delivered gas may improve these symptoms.

  3. A new positive pressure ventilation delivery system: its impact on lung ventilation studies that are technically inadequate or non diagnostic

    International Nuclear Information System (INIS)

    Bui, C.; Leiper, C.; Lee, K.; Saunders, C.; Dixson, H.; Elison, B.; Bennett, G.; Gibian, T.; Rutland, J.; Tse, V.; Elzein, H.; Babicheva, R.

    2000-01-01

    Full text: The objective of this study was to evaluate the efficacy and safety of an improved Positive Pressure Ventilation Delivery System (PVDS) in the investigation of Pulmonary Embolism (PE). The major component of PVDS is a commercially available, self-inflating 1.6L Hudson Resuscitator Bag, filled with either oxygen or air (if the patient has CO 2 retention), which is squeezed by the operator to push Technegas from the Technegas Generator Chamber to the patient via the Patient Administration Set synchronously with patient inspiration. 27 spontaneously breathing in-patients (12 males, 15 females, age range 64-89, 21 with chronic airflow limitation), whose conventional lung ventilation images were technically inadequate or non diagnostic, were re-scanned using PVDS within four days after the conventional ventilation study. Randomised blinded visual interpretation of conventional ventilation/perfusion scan vs. PVDS-assisted ventilation/perfusion scan was performed by consensus reading with two experienced observers. In conclusion PVDS was safe and well tolerated. PVDS improved the image quality of the lung ventilation scans in this cohort of patients. This technique has the potential to improve the accuracy of lung scanning in patients with severe lung disease. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc

  4. Role of non-invasive ventilation in difficult-to-wean children with acute neuromuscular disease.

    Science.gov (United States)

    Reddy, V G; Nair, M P; Bataclan, F

    2004-05-01

    Weaning from mechanical ventilation in children could be time-consuming and on many occasions, leads to reintubation with its associate complications. We report two children with acute neuromuscular disease, in whom bi-level positive airway pressure (BiPAP) as a mode of non-invasive ventilation was successfully used to wean the child from ventilators and prevented the need for tracheostomy. Despite the limited number of studies published in the literature suggesting BiPAP as a mode of weaning from mechanical ventilation, the technique when applied correctly seems to be safe and effective in weaning and avoiding tracheostomy.

  5. Prevention of hospital-acquired pneumonia in non-ventilated adult patients: a narrative review

    Directory of Open Access Journals (Sweden)

    Leonor Pássaro

    2016-11-01

    Full Text Available Abstract Background Pneumonia is one of the leading hospital-acquired infections worldwide and has an important impact. Although preventive measures for ventilator-associated pneumonia (VAP are well known, less is known about appropriate measures for prevention of hospital-acquired pneumonia (HAP. Aim The purpose of this narrative review is to provide an overview of the current standards for preventing HAP in non-ventilated adult patients. Methods A search of the literature up to May 2015 was conducted using Medline for guidelines published by national professional societies or professional medical associations. In addition, a comprehensive search for the following preventive measures was performed: hand hygiene, oral care, bed position, mobilization, diagnosis and treatment of dysphagia, aspiration prevention, viral infections and stress bleeding prophylaxis. Findings Regarding international guidelines, several measures were recommended for VAP, whilst no specific recommendations for HAP prevention in non-ventilated patients are available. There is reasonable evidence available that oral care is associated with a reduction in HAP. Early mobilization interventions, swift diagnosis and treatment of dysphagia, and multimodal programmes for the prevention of nosocomial influenza cross-infection, have a positive impact on HAP reduction. The impact of bed position and stress bleeding prophylaxis remains uncertain. Systematic antibiotic prophylaxis for HAP prevention should be avoided. Conclusion Scant literature and little guidance is available for the prevention of HAP among non-ventilated adult patients. In addition, the criteria used for the diagnosis of HAP and the populations targeted in the studies selected are heterogeneous. Oral care was the most studied measure and was commonly associated with a decrease in HAP rate, although a broad range of interventions are proposed. No robust evidence is available for other measures. Further high

  6. Prevention of hospital-acquired pneumonia in non-ventilated adult patients: a narrative review.

    Science.gov (United States)

    Pássaro, Leonor; Harbarth, Stephan; Landelle, Caroline

    2016-01-01

    Pneumonia is one of the leading hospital-acquired infections worldwide and has an important impact. Although preventive measures for ventilator-associated pneumonia (VAP) are well known, less is known about appropriate measures for prevention of hospital-acquired pneumonia (HAP). The purpose of this narrative review is to provide an overview of the current standards for preventing HAP in non-ventilated adult patients. A search of the literature up to May 2015 was conducted using Medline for guidelines published by national professional societies or professional medical associations. In addition, a comprehensive search for the following preventive measures was performed: hand hygiene, oral care, bed position, mobilization, diagnosis and treatment of dysphagia, aspiration prevention, viral infections and stress bleeding prophylaxis. Regarding international guidelines, several measures were recommended for VAP, whilst no specific recommendations for HAP prevention in non-ventilated patients are available. There is reasonable evidence available that oral care is associated with a reduction in HAP. Early mobilization interventions, swift diagnosis and treatment of dysphagia, and multimodal programmes for the prevention of nosocomial influenza cross-infection, have a positive impact on HAP reduction. The impact of bed position and stress bleeding prophylaxis remains uncertain. Systematic antibiotic prophylaxis for HAP prevention should be avoided. Scant literature and little guidance is available for the prevention of HAP among non-ventilated adult patients. In addition, the criteria used for the diagnosis of HAP and the populations targeted in the studies selected are heterogeneous. Oral care was the most studied measure and was commonly associated with a decrease in HAP rate, although a broad range of interventions are proposed. No robust evidence is available for other measures. Further high-quality studies are required to evaluate the impact of specific measures on

  7. Handling of bulk solids theory and practice

    CERN Document Server

    Shamlou, P A

    1990-01-01

    Handling of Bulk Solids provides a comprehensive discussion of the field of solids flow and handling in the process industries. Presentation of the subject follows classical lines of separate discussions for each topic, so each chapter is self-contained and can be read on its own. Topics discussed include bulk solids flow and handling properties; pressure profiles in bulk solids storage vessels; the design of storage silos for reliable discharge of bulk materials; gravity flow of particulate materials from storage vessels; pneumatic transportation of bulk solids; and the hazards of solid-mater

  8. The Value of CO2-Geothermal Bulk Energy Storage to Reducing CO2 Emissions Compared to Conventional Bulk Energy Storage Technologies

    Science.gov (United States)

    Ogland-Hand, J.; Bielicki, J. M.; Buscheck, T. A.

    2016-12-01

    Sedimentary basin geothermal resources and CO2 that is captured from large point sources can be used for bulk energy storage (BES) in order to accommodate higher penetration and utilization of variable renewable energy resources. Excess energy is stored by pressurizing and injecting CO2 into deep, porous, and permeable aquifers that are ubiquitous throughout the United States. When electricity demand exceeds supply, some of the pressurized and geothermally-heated CO2 can be produced and used to generate electricity. This CO2-BES approach reduces CO2 emissions directly by storing CO2 and indirectly by using some of that CO2 to time-shift over-generation and displace CO2 emissions from fossil-fueled power plants that would have otherwise provided electricity. As such, CO2-BES may create more value to regional electricity systems than conventional pumped hydro energy storage (PHES) or compressed air energy storage (CAES) approaches that may only create value by time-shifting energy and indirectly reducing CO2 emissions. We developed and implemented a method to estimate the value that BES has to reducing CO2 emissions from regional electricity systems. The method minimizes the dispatch of electricity system components to meet exogenous demand subject to various CO2 prices, so that the value of CO2 emissions reductions can be estimated. We applied this method to estimate the performance and value of CO2-BES, PHES, and CAES within real data for electricity systems in California and Texas over the course of a full year to account for seasonal fluctuations in electricity demand and variable renewable resource availability. Our results suggest that the value of CO2-BES to reducing CO2 emissions may be as much as twice that of PHES or CAES and thus CO2-BES may be a more favorable approach to energy storage in regional electricity systems, especially those where the topography is not amenable to PHES or the subsurface is not amenable to CAES.

  9. Early predictors of success of non-invasive positive pressure ventilation in hypercapnic respiratory failure.

    Science.gov (United States)

    Bhattacharyya, D; Prasad, Bnbm; Tampi, P S; Ramprasad, R

    2011-10-01

    Non-invasive positive pressure ventilation (NIPPV) has emerged as a significant advancement in the management of acute hypercapnic respiratory failure. Patients with hypercapnic respiratory failure requiring ventilation therapy (respiratory rate [RR] of > 30 breaths per minutes, PaCO2 > 55 mmHg and arterial pH success group and these parameters continued to improve even after four and 24 hours of NIPPV treatment. Out of 24 (24%) patients who failed to respond, 13 (54%) needed endotracheal intubation within one hour. The failure group had higher baseline HR than the success group. Improvement in HR, RR, pH, and PCO2 one hour after putting the patient on NIPPV predicts success of non-invasive positive pressure ventilation in hypercapnic respiratory failure.

  10. PBMR spent fuel bulk dry storage heat removal - HTR2008-58170

    International Nuclear Information System (INIS)

    De Wet, G. J.; Dent, C.

    2008-01-01

    A low decay heat (implying Spent Fuel (SF) pebbles older than 8-9 years) bulk dry storage section is proposed to supplement a 12-tank wet storage section. Decay heat removal by passive means must be guaranteed, taking into account the fact that dry storage vessels are under ground and inside the building footprint. Cooling takes place when ambient air (drawn downwards from ground level) passes on the outside of the 6 tanks' vessel containment (and gamma shielding), which is in a separate room inside the building, but outside PBMR building confinement and open to atmosphere. Access for loading/unloading of SF pebbles is only from the top of a tank, which is inside PBMR building confinement. No radioactive substances can therefore leak into atmosphere, as vessel design will take into account corrosion allowance. In this paper, it is shown (using CFD (Computational Fluid Dynamics) modelling and analytical analyses) that natural convection and draught induced flow combine to remove decay heat in a self-sustaining process. Decay heat is the energy source, which powers the draught inducing capability of the dry storage modular cell system: the more decay heat, the bigger the drive to expel heated air through a higher outlet and entrain cool ambient air from ground level to the bottom of the modular cell. (authors)

  11. [Reflections on the use of non-invasive mechanical ventilation in acute respiratory failure].

    Science.gov (United States)

    Scala, Raffaele

    2012-12-01

    Given its prevalence into the clinical practice, non-invasive ventilation (NIV) can be included among the cornerstones of medicine. Just think of the acute applications of NIV which are in constant expansion, from COPD exacerbation to severe de novo hypoxemia, from postoperative distress to extra-hospital use in acute pulmonary edema, from ongoing support of interventional procedures to delicate strategies for end of life in terminally ill oncologic and non-oncologic patients. The thought should be focused on how, by whom, where and to whom is delivered this mode of artificial ventilation to avoid the risk of trivialization and flattening.

  12. Determination of eustachius tube ventilation functioning among benign type chronic suppurative otitis media and non-otitis media subjects using sonotubometry

    Science.gov (United States)

    Ikhwan, M.; Hafil, A. F.; Bramanthyo, B.

    2017-08-01

    The Eustachian tube (ET) is responsible for the ventilation, protection, and cleaning of the middle ear. ET dysfunction plays an important role in the pathogenesis of otitis media cases, and thus the treatment and prognosis of these cases is extremely dependent on adequate ET function, which can ultimately affect the success rate of middle ear reconstruction practices. Data research on the ET’s ventilation function is needed to ensure the success of therapy and surgery treatments in the case of Chronic Suppurative Otitis Media (CSOM) patients. This study aims to investigate ET ventilation functioning in benign type CSOM and non-otitis media subjects and to develop another modality to measure ET ventilation functioning in patients with intact and perforated tympanic membranes. A comparative cross-sectional study of 36 benign type CSOM patients and 80 non-otitis media subjects will be conducted using sonotubometry and the rated parameter measurements of ET opening frequency, amplitude and ET opening duration. Malfunctioning ventilation of the ET is more common among benign type CSOM subjects (47%) than among non-otitis media subjects (18.75%). There is a significant difference (p = 0.002) between the ET ventilation functioning of benign type CSOM subjects and non-otitis media subjects—benign type CSOM subjects have rates of malfunctioning ET ventilation that are 3.88 times higher than those of non-otitis media subjects. Patients with benign type CSOM are more likely to experience malfunctioning ET ventilation than are non-otitis media subjects.

  13. The predictive value of respiratory function tests for non-invasive ventilation in amyotrophic lateral sclerosis

    NARCIS (Netherlands)

    Tilanus, T.B.M.; Groothuis, J.T.; Broek-Pastoor, J.M.C. ten; Feuth, T.; Heijdra, Y.F.; Slenders, J.P.L.; Doorduin, J.; Engelen, B.G.M. van; Kampelmacher, M.J.; Raaphorst, J.

    2017-01-01

    BACKGROUND: Non-invasive ventilation (NIV) improves survival and quality of life in amyotrophic lateral sclerosis (ALS) patients. The timing of referral to a home ventilation service (HVS), which is in part based on respiratory function tests, has shown room for improvement. It is currently unknown

  14. The predictive value of respiratory function tests for non-invasive ventilation in amyotrophic lateral sclerosis

    NARCIS (Netherlands)

    Tilanus, T. B. M.; Groothuis, J. T.; TenBroek-Pastoor, J. M. C.; Feuth, T. B.; Heijdra, Y. F.; Slenders, J. P. L.; Doorduin, J.; van Engelen, B. G.; Kampelmacher, M. J.; Raaphorst, J.

    2017-01-01

    Background: Non-invasive ventilation (NIV) improves survival and quality of life in amyotrophic lateral sclerosis (ALS) patients. The timing of referral to a home ventilation service (HVS), which is in part based on respiratory function tests, has shown room for improvement. It is currently unknown

  15. Hybrid Ventilation with Innovative Heat Recovery—A System Analysis

    Directory of Open Access Journals (Sweden)

    Bengt Hellström

    2013-02-01

    Full Text Available One of the most important factors when low energy houses are built is to have good heat recovery on the ventilation system. However, standard ventilation units use a considerable amount of electricity. This article discusses the consequences on a system level of using hybrid ventilation with heat recovery. The simulation program TRNSYS was used in order to investigate a ventilation system with heat recovery. The system also includes a ground source storage and waste water heat recovery system. The result of the analysis shows that the annual energy gain from ground source storage is limited. However, this is partly a consequence of the fact that the well functioning hybrid ventilation system leaves little room for improvements. The analysis shows that the hybrid ventilation system has potential to be an attractive solution for low energy buildings with a very low need for electrical energy.

  16. Analysis of density-wave oscillations in ventilated channels

    International Nuclear Information System (INIS)

    Taleyarkhan, R.; Podowski, M.; Lahey, R.T. Jr.

    1983-03-01

    A mathematical model has been developed for the linear stability analyses of a system of ventilated parallel boiling channels. The model can accomodate phasic slip, arbitrary non-uniform axial power distributions, distributed local losses, heater wall dynamics, channel-to-channel radial power skews, discrete or continuous ventilation between the channels, turbulent mixing between the channels, various donor-cell options for the lateral transport of energy and momentum, and a transverse momentum equation, including storage and crossflow inertia. A special matrix reduction scheme was developed to efficiently solve the system of linearized, Laplace transformed , nodal equations. The digital computer programs, MAZDA-1F, MAZDA-4S and MAZDA-4F, were written for the numerical evaluation of the mathematical model developed

  17. Effect of prophylactic non-invasive mechanical ventilation on functional capacity after heart valve replacement: a clinical trial

    Directory of Open Access Journals (Sweden)

    Amaro Afrânio de Araújo-Filho

    Full Text Available OBJECTIVE: During cardiac surgery, several factors contribute to the development of postoperative pulmonary complications. Non-invasive ventilation is a promising therapeutic tool for improving the functionality of this type of patient. The aim of this study is to evaluate the functional capacity and length of stay of patients in a nosocomial intensive care unit who underwent prophylactic non-invasive ventilation after heart valve replacement. METHOD: The study was a controlled clinical trial, comprising 50 individuals of both sexes who were allocated by randomization into two groups with 25 patients in each group: the control group and experimental group. After surgery, the patients were transferred to the intensive care unit and then participated in standard physical therapy, which was provided to the experimental group after 3 applications of non-invasive ventilation within the first 26 hours after extubation. For non-invasive ventilation, the positive pressure was 10 cm H2O, with a duration of 1 hour. The evaluation was performed on the 7th postoperative day/discharge and included a 6-minute walk test. The intensive care unit and hospitalization times were monitored in both groups. Brazilian Registry of Clinical Trials (REBeC: RBR number 8bxdd3. RESULTS: Analysis of the 6-minute walk test showed that the control group walked an average distance of 264.34±76 meters and the experimental group walked an average distance of 334.07±71 meters (p=0.002. The intensive care unit and hospitalization times did not differ between the groups. CONCLUSION: Non-invasive ventilation as a therapeutic resource was effective toward improving functionality; however, non-invasive ventilation did not influence the intensive care unit or hospitalization times of the studied cardiac patients.

  18. An Investigation into the Non-bulk Rail Freight Transport in Australia

    OpenAIRE

    Hadi Ghaderi; Stephen Cahoon; Hong-Oanh Nguyen

    2015-01-01

    In the last decade freight transport has gained further momentum in Australia, partly through significant demand growth at both domestic and international levels and partly as the result of Australia's long term need for infrastructure decision making. Amongst the freight task, non-bulk freight is the fastest growing freight task in Australia and is forecast to grow much faster than the rate of population growth and the average national GDP growth. However, rail's share in the non-bulk market...

  19. Effect of different bulking agents on water variation and thermal balance and their respective contribution to bio-generated heat during long-term storage sludge biodrying process.

    Science.gov (United States)

    Liu, Tiantian; Cui, Chongwei; He, Junguo; Tang, Jian

    2018-04-17

    Biodrying was first used for the post-treatment of long-term storage sludge with vinasse as bulking agents. The effect of different bulking agents on water and heat variation and their respective contributions to bio-generated heat during storage sludge biodrying were investigated. Three different bulking agents (beer lees and distillers grains, with conventional straw used for comparison) were mixed with storage sludge for biodrying for an 18-day period. The results revealed the treatment with beer lees as bulking agent achieved the best performance with the highest water removal capacity (658 g kg -1 initial water). The extent of organic degradation in the mixture was related to the degradation ability of the bulking agents. The degradation of C- and H-containing materials (e.g., carboxylic acid) accounted for volatile solids (VS) loss. Water and thermal analyses showed that evaporation was the main way of water loss (accounting for 90%), while evaporation heat was the main component of heat consumption (accounting for 56.67-60.62%).The biodegradation of bulking agents contributed a high proportion of the bio-generated heat consumed by water evaporation (82.35-86.67%).

  20. Thermal energy storage in granular deposits

    Science.gov (United States)

    Ratuszny, Paweł

    2017-10-01

    Energy storage technology is crucial for the development of the use of renewable energy sources. This is a substantial constraint, however it can, to some extent, be solved by storing energy in its various forms: electrical, mechanical, chemical and thermal. This article presents the results of research in thermal properties of granular deposits. Correlation between temperature changes in the stores over a period of time and their physical properties has been studied. The results of the research have practical application in designing thermal stores based on bulk materials and ground deposits. Furthermore, the research results are significant for regeneration of the lower ground sources for heat pumps and provide data for designing ground heat exchangers for ventilation systems.

  1. Tidal ventilation distribution during pressure-controlled ventilation and pressure support ventilation in post-cardiac surgery patients.

    Science.gov (United States)

    Blankman, P; VAN DER Kreeft, S M; Gommers, D

    2014-09-01

    Inhomogeneous ventilation is an important contributor to ventilator-induced lung injury. Therefore, this study examines homogeneity of lung ventilation by means of electrical impedance tomography (EIT) measurements during pressure-controlled ventilation (PCV) and pressure support ventilation (PSV) using the same ventilation pressures. Twenty mechanically ventilated patients were studied after cardiac surgery. On arrival at the intensive care unit, ventilation distribution was measured with EIT just above the diaphragm for 15 min. After awakening, PCV was switched to PSV and EIT measurements were again recorded. Tidal impedance variation, a measure of tidal volume, increased during PSV compared with PCV, despite using the same ventilation pressures (P = 0.045). The distribution of tidal ventilation to the dependent lung region was more pronounced during PSV compared with PCV, especially during the first half of the inspiration. An even distribution of tidal ventilation between the dependent and non-dependent lung regions was seen during PCV at lower tidal volumes (tidal volumes (≥ 8 ml/kg). In addition, the distribution of tidal ventilation was predominantly distributed to the dependent lung during PSV at low tidal volumes. In post-cardiac surgery patients, PSV showed improved ventilation of the dependent lung region due to the contribution of the diaphragm activity, which is even more pronounced during lower assist levels. © 2014 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  2. Ventilation and ventilation/perfusion ratios

    International Nuclear Information System (INIS)

    Valind, S.O.

    1989-01-01

    The thesis is based on five different papers. The labelling of specific tracer compounds with positron emitting radionuclides enables a range of structural, physiological and biochemical parameters in the lung to be measured non-invasively, using positron emission tomography. This concept affords a unique opportunity for in vivo studies of different expressions of pulmonary pathophysiology at the regional level. The present thesis describes the application of positron emission tomography to the measurements of ventilation and ventilation/perfusion ratios using inert gas tracers, neon-19 and nitrogen-13 respectively. The validity of the methods applied was investigated with respect to the transport of inert gas tracers in the human lung. Both ventilation and the ventilation/perfusion ratio may be obtained with errors less than 10 % in the normal lung. In disease, however, errors may increase in those instances where the regional ventilation is very low or the intra-regional gas flow distribution is markedly nonuniform. A 2-3 fold increase in ventilation was demonstrated in normal nonsmoking subjects going from ventral to dorsal regions in the supine posture. These large regional differences could be well explained by the intrinsic elastic properties of lung tissue, considering the gravitational gradient in transpulmonary pressure. In asymptomatic smokers substantial regional ventilatroy abnormalities were found whilst the regional gas volume was similar in smokers and nonsmokers. The uncoupling between ventilation and gas volume probably reflects inflammatory changes in the airways. The regional differences in dV/dt/dQ/dt were relatively small and blood flow was largely matched to ventilation in the supine posture. However, small regions of lung with very low ventilation, unmatched by blood flow commonly exists in the most dependent parts of the lung in both smokers and nonsmokers. (29 illustrations, 7 tables, 113 references)

  3. Ventilation area measured with eit in order to optimize peep settings in mechanically ventilated patients

    NARCIS (Netherlands)

    Blankman, P; Groot Jebbink, E; Preis, C; Bikker, I.; Gommers, D.

    2012-01-01

    INTRODUCTION. Electrical Impedance Tomography (EIT) is a non-invasive imaging technique, which can be used to visualize ventilation. Ventilation will be measured by impedance changes due to ventilation. OBJECTIVES. The aim of this study was to optimize PEEP settings based on the ventilation area of

  4. Coordinated Control of Distributed and Bulk Energy Storage for Alleviation of Post-Contingency Overloads

    Directory of Open Access Journals (Sweden)

    Yunfeng Wen

    2014-03-01

    Full Text Available This paper presents a novel corrective control strategy that can effectively coordinate distributed and bulk energy storage to relieve post-contingency overloads. Immediately following a contingency, distributed batteries are implemented to provide fast corrective actions to reduce power flows below their short-term emergency ratings. During the long-term period, Pumped Hydro Storage units work in pumping or generation mode to aid conventional generating units keep line flows below the normal ratings. This problem is formulated as a multi-stage Corrective Security-constrained OPF (CSCOPF. An algorithm based on Benders decomposition was proposed to find the optimal base case solution and seek feasible corrective actions to handle all contingencies. Case studies based on a modified RTS-96 system demonstrate the performance and effectiveness of the proposed control strategy.

  5. Long-term storage of irradiated potatoes for processing use, 4

    International Nuclear Information System (INIS)

    Aoki, Shohei; Umeda, Keiji; Kameyama, Kenji.

    1984-01-01

    In order to develop suitable storage conditions in potatoes for processing use, non-irradiated and irradiated potatoes var. Norin No. 1 were stored in containers and in bulk. The contents of reducing sugars were determined and the properties of potato chips were analysed. Reconditioning at 10 deg C and RH 90 % for 4 weeks during an early period of dormancy lowered the content of reducing sugars remarkably in both the non-irradiated and irradiated potatoes which were either stored in containers or in bulk. The optimum conditions for the storage of potatoes were 8 deg C and RH 90 %, which enabled the potatoes to retain their hardness while the content reducing sugars decreased. The potatoes stored under the above conditions gave chips with a fairly good color. In contrast, the non-irradiated potatoes stored for a period of 6 months or longer sprouted and aged, resulting in chips with unsatisfactory color. It was found necessary to use potatoes with low contents of both amino acids and reducing sugars to avoid the browning of chips. Bulk storage which was found to be effective for air circulation through potatoes caused creeping phenomenon. (author)

  6. Non-invasive ventilation effectiveness and the effect of ventilatory mode on survival in ALS patients.

    Science.gov (United States)

    Sancho, Jesus; Servera, Emilio; Morelot-Panzini, Capucine; Salachas, François; Similowski, Thomas; Gonzalez-Bermejo, Jesus

    2014-03-01

    Non-invasive ventilation (NIV) prolongs survival in amyotrophic lateral sclerosis (ALS), but there are no data with which to compare the effectiveness of the different ventilator modes - volume (Vol-NIV) or pressure-cycled (Pres-NIV) ventilation - in ALS. We aimed to determine whether the ventilatory mode has an effect on ventilation effectiveness and survival of ALS patients using NIV. We used a retrospective study that included all ALS patients for whom NIV was indicated in two referral units: one using Vol-NIV and the other using Pres-NIV. Demographic, functional and nocturnal gas exchange parameters at NIV initiation were recorded. Eighty-two ALS patients ventilated using Pres-NIV and 62 using Vol-NIV were included. No differences were found in survival from NIV initiation between Vol-NIV (median 15.00 (7.48-22.41) months) and Pres-NIV (median 15.00 (10.25-19.75) months, p = 0.533) patients. Effective NIV was achieved in 72.41% Vol-NIV patients and in 48.78% Pres-NIV patients (p NIV. In conclusion, although Vol-NIV provides more effective ventilation, Vol-NIV and Pres-NIV present similar survival in ALS. Effectiveness of NIV is related to the severity of bulbar dysfunction.

  7. In-vitro characterisation of the nebulised dose during non-invasive ventilation.

    Science.gov (United States)

    Abdelrahim, Mohamed E; Plant, Paul; Chrystyn, Henry

    2010-08-01

    Non-invasive ventilation (NIV) with nebulised bronchodilators helps some patients to maintain effective ventilation. However, the position of the nebuliser in the ventilation circuit may affect lung delivery. We placed the nebuliser proximal (A) and distal (B) to a breathing simulator in a standard NIV circuit with inspiratory (I) and expiratory (E) pressures of 20 and 5 cm H(2)O, 1 : 3 I : E ratio, 15 breaths/min and a tidal volume of 500 ml. Five milligrams of terbutaline solution was nebulised using an Aeroneb Pro (AERO) and a Sidestream (SIDE) nebuliser. The fate of the nebulised dose was determined and the aerodynamic droplet characteristics were measured using a cooled Next Generation Impactor. More terbutaline was entrained on the inhalation filter in position A than in position B (P AEROB, SIDEA and SIDEB were 1.31 (0.2), 1.13 (0.14), 0.56 (0.03) and 0.39 (0.13) mg. These amounts from AEROA were significantly greater (P < 0.001) than those of the other three methods. The results highlight the differences between nebulisers and the influence on the placement of the nebuliser in the NIV circuit.

  8. Clinical characteristics of long-term survival with non-invasive ventilation and factors affecting the transition to invasive ventilation in ALS.

    Science.gov (United States)

    Hirose, Takahiko; Kimura, Fumiharu; Tani, Hiroki; Ota, Shin; Tsukahara, Akihiro; Sano, Eri; Shigekiyo, Taro; Nakamura, Yoshitsugu; Kakiuchi, Kensuke; Motoki, Mikiko; Unoda, Kiichi; Ishida, Simon; Nakajima, Hideto; Arawaka, Shigeki

    2018-04-20

    Introduction We evaluated post non-invasive ventilation survival and factors for the transition to tracheostomy in amyotrophic lateral sclerosis. Methods We analyzed 197 patients using a prospectively-collected database, with 114 patients since 2000. Results Of 114 patients, 59 patients underwent non-invasive ventilation (NIV), which prolonged the total median survival time to 43 months compared with 32 months without treatment. The best post-NIV survival was associated with a lack of bulbar symptoms, higher measured pulmonary function, and a slower rate of progression at diagnosis. The transition rate from NIV to tracheostomy gradually decreased over the years. Patients using NIV for more than 6 months were more likely to refuse tracheostomy and to be female. Discussion This study confirmed a positive survival effect with NIV, which was less effective in patients with bulbar dysfunction. Further studies are necessary to determine the best timing for using NIV with ALS in patients with bulbar dysfunction. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

  9. The predictive value of respiratory function tests for non-invasive ventilation in amyotrophic lateral sclerosis

    OpenAIRE

    Tilanus, T. B. M.; Groothuis, J. T.; TenBroek-Pastoor, J. M. C.; Feuth, T. B.; Heijdra, Y. F.; Slenders, J. P. L.; Doorduin, J.; Van Engelen, B. G.; Kampelmacher, M. J.; Raaphorst, J.

    2017-01-01

    BACKGROUND: Non-invasive ventilation (NIV) improves survival and quality of life in amyotrophic lateral sclerosis (ALS) patients. The timing of referral to a home ventilation service (HVS), which is in part based on respiratory function tests, has shown room for improvement. It is currently unknown which respiratory function test predicts an appropriate timing of the initiation of NIV. METHODS: We analysed, retrospectively, serial data of five respiratory function tests: forced vital capacity...

  10. Ventilation and health in non-industrial indoor environments: report from a European Multidisciplinary Scientific Consensus Meeting (EUROVEN)

    DEFF Research Database (Denmark)

    Wargocki, Pawel; Sundell, Jan; Bischof, W.

    2002-01-01

    Scientific literature on the effects of ventilation on health, comfort, and productivity in non-industrial indoor environments (offices, schools, homes, etc.) has been reviewed by a multidisciplinary group of European scientists, called EUROVEN, with expertise in medicine, epidemiology, toxicology......, and engineering. The group reviewed 105 papers published in peer-reviewed scientific journals and judged 30 as conclusive, providing sufficient information on ventilation, health effects, data processing, and reporting, 14 as providing relevant background information on the issue, 43 as relevant but non......-informative or inconclusive, and 18 as irrelevant for the issue discussed. Based on the data in papers judged conclusive, the group agreed that ventilation is strongly associated with comfort (perceived air quality) and health (Sick Building Syndrome (SBS) symptoms, inflammation, infections, asthma, allergy, short-term sick...

  11. Electrostatic Self-Assembly Enabling Integrated Bulk and Interfacial Sodium Storage in 3D Titania-Graphene Hybrid.

    Science.gov (United States)

    Xu, Gui-Liang; Xiao, Lisong; Sheng, Tian; Liu, Jianzhao; Hu, Yi-Xin; Ma, Tianyuan; Amine, Rachid; Xie, Yingying; Zhang, Xiaoyi; Liu, Yuzi; Ren, Yang; Sun, Cheng-Jun; Heald, Steve M; Kovacevic, Jasmina; Sehlleier, Yee Hwa; Schulz, Christof; Mattis, Wenjuan Liu; Sun, Shi-Gang; Wiggers, Hartmut; Chen, Zonghai; Amine, Khalil

    2018-01-10

    Room-temperature sodium-ion batteries have attracted increased attention for energy storage due to the natural abundance of sodium. However, it remains a huge challenge to develop versatile electrode materials with favorable properties, which requires smart structure design and good mechanistic understanding. Herein, we reported a general and scalable approach to synthesize three-dimensional (3D) titania-graphene hybrid via electrostatic-interaction-induced self-assembly. Synchrotron X-ray probe, transmission electron microscopy, and computational modeling revealed that the strong interaction between titania and graphene through comparably strong van der Waals forces not only facilitates bulk Na + intercalation but also enhances the interfacial sodium storage. As a result, the titania-graphene hybrid exhibits exceptional long-term cycle stability up to 5000 cycles, and ultrahigh rate capability up to 20 C for sodium storage. Furthermore, density function theory calculation indicated that the interfacial Li + , K + , Mg 2+, and Al 3+ storage can be enhanced as well. The proposed general strategy opens up new avenues to create versatile materials for advanced battery systems.

  12. Electrostatic Self-Assembly Enabling Integrated Bulk and Interfacial Sodium Storage in 3D Titania-Graphene Hybrid

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Gui-Liang [Chemical; Xiao, Lisong [Center; Sheng, Tian [Collaborative; Liu, Jianzhao [Chemical; Hu, Yi-Xin [Chemical; Department; Ma, Tianyuan [Chemical; Amine, Rachid [Materials; Xie, Yingying [Chemical; Zhang, Xiaoyi [X-ray Science; Liu, Yuzi [Nanoscience; Ren, Yang [X-ray Science; Sun, Cheng-Jun [X-ray Science; Heald, Steve M. [X-ray Science; Kovacevic, Jasmina [Center; Sehlleier, Yee Hwa [Center; Schulz, Christof [Center; Mattis, Wenjuan Liu [Microvast Power Solutions, 12603; Sun, Shi-Gang [Collaborative; Wiggers, Hartmut [Center; Chen, Zonghai [Chemical; Amine, Khalil [Chemical

    2017-12-15

    Room temperature sodium-ion batteries have attracted increased attention for energy storage due to the natural abundance of sodium. However, it remains a huge challenge to develop versatile electrode materials with favorable properties, which requires smart structure design and good mechanistic understanding. Herein, we reported a general and scalable approach to synthesize 3D titania-graphene hybrid via electrostatic-interaction-induced self-assembly. Synchrotron X-ray probe, transmission electron microscopy and computational modeling revealed that the strong interaction between Titania and graphene through comparably strong van-der-Waals forces not only facilitates bulk Na+ intercalation but also enhances the interfacial sodium storage. As a result, the titania-graphene hybrid exhibits exceptional long-term cycle stability up to 5000 cycles, and ultrahigh rate capability up to 20 C for sodium storage. Furthermore, density function theory calculation indicated that the interfacial Li+, K+, Mg2+ and Al3+ storage can be enhanced as well. The proposed general strategy opens up new avenues to create versatile materials for advanced battery systems.

  13. Ventilation of uranium mines

    International Nuclear Information System (INIS)

    Francois, Y.; Pradel, J.; Zettwoog, P.; Dumas, M.

    1975-01-01

    In the first part of the paper the authors describe the ventilation of French mines in terms of the primary ventilation system, which brings the outside air close to the working places using the overall structure of the mine to form the airways, and the secondary ventilation system, which is for the distribution of the primary air or for the ventilation of the development drifts and blind tunnels. Brief mention is made of the French regulations on the ventilation of mines in general and uranium mines in particular. The authors describe the equipment used and discuss the installed capacities and air flow per man and per working place. The difficulties encountered in properly ventilating various types of working places are mentioned, such as sublevel development drifts, reinforced stopes, and storage chambers with an artificial crown. The second part of the paper is devoted to computer calculations of the primary ventilation system. It is explained why the Commissariat a l'energie atomique has found it necessary to make these calculations. Without restating the mathematical theories underlying the methods employed, the authors demonstrate how simple measuring instruments and a small-size computer can be used to solve the ventilation problems arising in French mines. Emphasis is given to the layout of the ventilation system and to air flow and negative pressure measurements at the base of the mine. The authors show how calculations can be applied to new heading operations, a change in resistance, the replacement or addition of a ventilator, and a new air inlet or outlet. The authors come to the conclusion that since ventilation is at present the most reliable way of avoiding the pollution of mines, a thorough knowledge of the capabilities in this respect can often help improve working conditions. Despite the progress made, however, constant surveillance of the ventilation systems in uranium mines by a separate team with no responsibility for production problems is

  14. Ventilation of uranium mines

    International Nuclear Information System (INIS)

    Francois, Y.; Pradel, J.; Zettwoog, P.; Dumas, M.

    1975-01-01

    In the first part of the paper the authors describe the ventilation of French mines in terms of the primary ventilation system, which brings the outside air close to the working places using the overall structure of the mine to form the airways, and the secondary ventilation system, which is for the distribution of the primary air or for the ventilation of the development drifts and blind tunnels. Brief mention is made of the French regulations on the ventilation of mines in general and uranium mines in particular. The authors describe the equipment used and discuss the installed capacities and air flow per man and per working place. The difficulties encountered in properly ventilating various types of working places are mentioned, such as sub-level development drifts, reinforced stopes, and storage chambers with an artificial crown. The second part of the paper is devoted to computer calculations of the primary ventilation system. It is explained why the Commissariat a l'energie atomique has found it necessary to make these calculations. Without restating the mathematical theories underlying the methods employed, the authors demonstrate how simple measuring instruments and a small-size computer can be used to solve the ventilation problems arising in French mines. Emphasis is given to the layout of the ventilation system and to air flow and negative pressure measurements at the base of the mine. The authors show how calculations can be applied to new heading operations, a change in resistance, the replacement or addition of a ventilator, and a new air inlet or outlet. The authors come to the conclusion that since ventilation is at present the most reliable way of avoiding the pollution of mines, a thorough knowledge of the capabilities in this respect can often help improve working conditions. Despite the progress made, however, constant surveillance of the ventilation systems in uranium mines by a separate team with no responsibility for production problems is

  15. Liquid Ventilation

    Directory of Open Access Journals (Sweden)

    Qutaiba A. Tawfic

    2011-01-01

    Full Text Available Mammals have lungs to breathe air and they have no gills to breath liquids. When the surface tension at the air-liquid interface of the lung increases, as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen, as the inert carrier of oxygen and carbon dioxide offers a number of theoretical advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. The potential for multiple clinical applications for liquid-assisted ventilation will be clarified and optimized in future. Keywords: Liquid ventilation; perfluorochemicals; perfluorocarbon; respiratory distress; surfactant.

  16. Short-term bulk energy storage system scheduling for load leveling in unit commitment: modeling, optimization, and sensitivity analysis

    Science.gov (United States)

    Hemmati, Reza; Saboori, Hedayat

    2016-01-01

    Energy storage systems (ESSs) have experienced a very rapid growth in recent years and are expected to be a promising tool in order to improving power system reliability and being economically efficient. The ESSs possess many potential benefits in various areas in the electric power systems. One of the main benefits of an ESS, especially a bulk unit, relies on smoothing the load pattern by decreasing on-peak and increasing off-peak loads, known as load leveling. These devices require new methods and tools in order to model and optimize their effects in the power system studies. In this respect, this paper will model bulk ESSs based on the several technical characteristics, introduce the proposed model in the thermal unit commitment (UC) problem, and analyze it with respect to the various sensitive parameters. The technical limitations of the thermal units and transmission network constraints are also considered in the model. The proposed model is a Mixed Integer Linear Programming (MILP) which can be easily solved by strong commercial solvers (for instance CPLEX) and it is appropriate to be used in the practical large scale networks. The results of implementing the proposed model on a test system reveal that proper load leveling through optimum storage scheduling leads to considerable operation cost reduction with respect to the storage system characteristics. PMID:27222741

  17. Short-term bulk energy storage system scheduling for load leveling in unit commitment: modeling, optimization, and sensitivity analysis.

    Science.gov (United States)

    Hemmati, Reza; Saboori, Hedayat

    2016-05-01

    Energy storage systems (ESSs) have experienced a very rapid growth in recent years and are expected to be a promising tool in order to improving power system reliability and being economically efficient. The ESSs possess many potential benefits in various areas in the electric power systems. One of the main benefits of an ESS, especially a bulk unit, relies on smoothing the load pattern by decreasing on-peak and increasing off-peak loads, known as load leveling. These devices require new methods and tools in order to model and optimize their effects in the power system studies. In this respect, this paper will model bulk ESSs based on the several technical characteristics, introduce the proposed model in the thermal unit commitment (UC) problem, and analyze it with respect to the various sensitive parameters. The technical limitations of the thermal units and transmission network constraints are also considered in the model. The proposed model is a Mixed Integer Linear Programming (MILP) which can be easily solved by strong commercial solvers (for instance CPLEX) and it is appropriate to be used in the practical large scale networks. The results of implementing the proposed model on a test system reveal that proper load leveling through optimum storage scheduling leads to considerable operation cost reduction with respect to the storage system characteristics.

  18. Development of non-invasive ventilation treatment practice for patients with chronic obstructive pulmonary disease

    DEFF Research Database (Denmark)

    Christensen, Helle M; Titlestad, Ingrid L; Huniche, Lotte

    2017-01-01

    Objectives: Non-invasive ventilation treatment for patients with acute exacerbation of chronic obstructive pulmonary disease is well documented. Communication with patients during treatment is inhibited because of the mask, the noise from the machine and patient distress. Assessing life expectanc...

  19. An analysis of density-wave oscillations in ventilated channels

    International Nuclear Information System (INIS)

    Taleyarkhan, R.P.

    1982-01-01

    A mathematical model has been developed for the linear stability analyses of a system of ventilated parallel boiling channels. The model can accommodate phasic slip, arbitrary non-uniform axial power distributions, distributed local losses, heater wall dynamics, channel-to-channel radial power skews, discrete or continuous ventilation between the channels, turbulent mixing between the channels, various donor-cell options for the lateral transport of energy and momentum, and a transverse momentum equation, including storage and cross-flow inertia. A special matrix reduction scheme was developed to efficiently solve the system of linearized, Laplace transformed, nodal equations. The digital computer programs, MAZDA-1F, MAZDA-4S and MAZDA-4F, were written for the numerical evaluation of the mathematical model developed. MAZDA-1F is a frequency domain code which can be used for the study of linear stability of a single boiling channel. MAZDA-4S evaluates the steady-state flow and pressure fields in a system of ventilated parallel channels. The frequency domain code, MAZDA-4F, can then be used to assess the linear stability of the flow field obtained with MAZDA-4S. A parametric study using MAZDA-1F and MAZDA-4F revealed that phasic slip, axial power distribution, heater wall dynamics, local losses, lateral ventilation and radial power skew can have a significant effect on the stability characteristics of the system

  20. Non-invasive mechanical ventilation after the successful weaning: a comparison with the venturi mask

    Directory of Open Access Journals (Sweden)

    Esra Adıyeke

    Full Text Available Abstract Background and objectives: This study compared the rates of acute respiratory failure, reintubation, length of intensive care stay and mortality in patients in whom the non-invasive mechanical ventilation (NIMV was applied instead of the routine venturi face mask (VM application after a successful weaning. Methods: Following the approval of the hospital ethics committee, 62 patients who were under mechanical ventilation for at least 48 hours were scheduled for this study. 12 patients were excluded because of the weaning failure during T-tube trial. The patients who had optimum weaning criteria after the T-tube trial of 30 minutes were extubated. The patients were kept on VM for 1 hour to observe the hemodynamic and respiratory stability. The group of 50 patients who were successful to wean randomly allocated to have either VM (n = 25, or NIV (n = 25. Systolic arterial pressure (SAP, heart rate (HR, respiratory rate (RR, PaO2, PCO2, and pH values were recorded. Results: The number of patients who developed respiratory failure in the NIV group was significantly less than VM group of patients (3 reintubation vs. 14 NIV + 5 reintubation in the VM group. The length of stay in the ICU was also significantly shorter in NIV group (5.2 ± 4.9 vs. 16.7 ± 7.7 days. Conclusions: The ratio of the respiratory failure and the length of stay in the ICU were lower when non-invasive mechanical ventilation was used after extubation even if the patient is regarded as ‘successfully weaned’. We recommend the use of NIMV in such patients to avoid unexpected ventilator failure.

  1. Clinical challenges in mechanical ventilation.

    Science.gov (United States)

    Goligher, Ewan C; Ferguson, Niall D; Brochard, Laurent J

    2016-04-30

    Mechanical ventilation supports gas exchange and alleviates the work of breathing when the respiratory muscles are overwhelmed by an acute pulmonary or systemic insult. Although mechanical ventilation is not generally considered a treatment for acute respiratory failure per se, ventilator management warrants close attention because inappropriate ventilation can result in injury to the lungs or respiratory muscles and worsen morbidity and mortality. Key clinical challenges include averting intubation in patients with respiratory failure with non-invasive techniques for respiratory support; delivering lung-protective ventilation to prevent ventilator-induced lung injury; maintaining adequate gas exchange in severely hypoxaemic patients; avoiding the development of ventilator-induced diaphragm dysfunction; and diagnosing and treating the many pathophysiological mechanisms that impair liberation from mechanical ventilation. Personalisation of mechanical ventilation based on individual physiological characteristics and responses to therapy can further improve outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Numerical analysis of passive strategies for energy retrofit of existing buildings in Mediterranean climate: thermal mass and natural ventilation combination

    Directory of Open Access Journals (Sweden)

    Calcerano Filippo

    2017-01-01

    Full Text Available The study investigates the potential of coupling natural ventilation and thermal storage systems to improve hygrothermal comfort and reduce energy consumption during summer season in an existing building in the Mediterranean. It aims at bridging the knowledge gap between designers, researchers and building scientists, fostering a multidisciplinary approach and promoting numerical simulation of the energy performance of buildings within architectural professional practice. The study analyses the interaction between six natural ventilation systems (single sided ventilation through facade openings; cross ventilation through facade openings, inlet wind tower, thermal chimney, evaporative cool tower, earth pipes and with two thermal storage typology (heavy and medium-light within four strategic Italian location (Rome, Naples, Messina and Catania. For each interaction we perform a numerical dynamic simulation of indoor comfort, indoor air quality and energy consumption during the summer period, on a reference building model corresponding to the most common Italian typology. Results show that the use of the chosen systems ensures significant reductions of discomfort hours and energy consumption in all configurations. The study also highlights the high efficiency of non invasive systems (single-sided and cross ventilation with automatic control present discomfort hours reduction and energy consumption reduction above 68% for all combinations and the significant influence of the daily thermal range value on the performance of systems without air pre-treatment.

  3. Occupational exposure of aldehydes resulting from the storage of wood pellets.

    Science.gov (United States)

    Rahman, Mohammad Arifur; Rossner, Alan; Hopke, Philip K

    2017-06-01

    An exposure assessment was conducted to investigate the potential for harmful concentrations of airborne short chain aldehydes emitted from recently stored wood pellets. Wood pellets can emit a number of airborne aldehydes include acetaldehyde, formaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, and hexanal. Exposure limits have been set for these compounds since they can result in significant irritation of the upper respiratory system at elevated concentrations. Formaldehyde is a recognized human carcinogen and acetaldehyde is an animal carcinogen. Thus, air sampling was performed in a wood pellet warehouse at a pellet mill, two residential homes with bulk wood pellet storage bins, and in controlled laboratory experiments to evaluate the risk to occupants. Using NIOSH method 2539, sampling was conducted in five locations in the warehouse from April-June 2016 when it contained varying quantities of bagged pellets as well as two homes with ten ton bulk storage bins. The aldehyde concentrations were found to increase with the amount of stored pellets. Airborne concentrations of formaldehyde were as high as 0.45 ppm in the warehouse exceeding the NIOSH REL-C, and ACGIH TLV-C occupational exposure limits (OELs). The concentrations of aldehydes measured in the residential bins were also elevated indicating emissions may raise indoor air quality concerns for occupants. While individual exposures are of concern the combined irritant effect of all the aldehydes is a further raise the concerns for building occupants. To minimize exposure and the risk of adverse health effects to a building's occupants in storage areas with large quantities of pellets, adequate ventilation must be designed into storage areas.

  4. Testing and COBRA-SFS analysis of the VSC-17 ventilated concrete, spent fuel storage cask

    International Nuclear Information System (INIS)

    McKinnon, M.A.; Dodge, R.E.; Schmitt, R.C.

    1992-04-01

    A performance test of a Pacific Sierra Nuclear VSC-17 ventilated concrete storage cask loaded with 17 canisters of consolidated PWR spent fuel generating approximately 15 kW was conducted. The performance test included measuring the cask surface, concrete, air channel surface, and fuel temperatures, as well as cask surface gamma and neutron dose rates. Testing was performed using vacuum, nitrogen, and helium backfill environments. Pretest predictions of cask thermal performance were made using the COBRA-SFS computer code. Analysis results were within 15 degrees C of measured peak fuel temperature. Peak fuel temperature for normal operation was 321 degrees C. In general, the surface dose rates were less than 30 mrem/h on the side of the cask and 40 mrem/h on the top of the cask

  5. Developing semi-analytical solution for multiple-zone transient storage model with spatially non-uniform storage

    Science.gov (United States)

    Deng, Baoqing; Si, Yinbing; Wang, Jia

    2017-12-01

    Transient storages may vary along the stream due to stream hydraulic conditions and the characteristics of storage. Analytical solutions of transient storage models in literature didn't cover the spatially non-uniform storage. A novel integral transform strategy is presented that simultaneously performs integral transforms to the concentrations in the stream and in storage zones by using the single set of eigenfunctions derived from the advection-diffusion equation of the stream. The semi-analytical solution of the multiple-zone transient storage model with the spatially non-uniform storage is obtained by applying the generalized integral transform technique to all partial differential equations in the multiple-zone transient storage model. The derived semi-analytical solution is validated against the field data in literature. Good agreement between the computed data and the field data is obtained. Some illustrative examples are formulated to demonstrate the applications of the present solution. It is shown that solute transport can be greatly affected by the variation of mass exchange coefficient and the ratio of cross-sectional areas. When the ratio of cross-sectional areas is big or the mass exchange coefficient is small, more reaches are recommended to calibrate the parameter.

  6. Characterization of bulk and shear properties of basmati and non-basmati rice flour.

    Science.gov (United States)

    Jan, Shumaila; Ghoroi, Chinmay; Saxena, Dharmesh Chandra

    2018-01-01

    Flours are often unstable in relation to their flow performance, which is evident when a free-flowing material ceases to flow and the processing, handling, and production parameters depend on the inherent powder characteristics and their bulk behaviour. The present study was conducted to compare the flowability of basmati and non-basmati rice flour affecting bulk handling, which could be related to its particle size, shape and surface roughness (measured by atomic force microscopy) as well as bulk and shear properties, depending upon the processing conditions. Particle size (171.1-171.9 μm) of both samples was not significantly different. However, the flowability of the non-basmati rice flour was significantly affected by its particle shape (circularity 0.487), surface roughness (124.23 nm) and compressibility (25.32%) in comparison to basmati rice flour (circularity 0.653, surface roughness 113.59 nm and compressibility 21.09%), making it more cohesive than basmati rice flour. Also, basic flow energy was significantly higher in non-basmati flour, thus requiring more energy (147.54 mJ) to flow than basmati rice flour (130.15 mJ). Overall, flowability was analysed by applying three different pressures (3, 6 and 9 kPa), among which non-basmati rice flour was found to be less flowable (flow function coefficient (FFC) 2.33 at 9 kPa) in comparison to basmati (FFC 3.35 at 9 kPa), making bulk handling difficult. This study could be useful in designing processing equipment, hoppers and silos for rice flour handling. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  7. Temperature control of paddy bulk storage with aeration-thermosyphon heat pipe

    International Nuclear Information System (INIS)

    Dussadee, Natthawud; Punsaensri, Tammasak; Kiatsiriroat, Tanongkiat

    2007-01-01

    A technology of an aeration-thermosyphon heat pipe is developed for controlling paddy temperature in a paddy bulk silo. A prototype of paddy bulk storage of 1000 kg has a set of copper tubes with steel fins embedded in the paddy bed. The total heat transfer area of the tubes with fins is 16 m 2 . The tubes act as the evaporator of a thermosyphon heat pipe and absorb heat resulting from the paddy respiration. The thermosyphon has a total condenser area of 12.2 m 2 that is exposed to ambient air. At the bottom of the silo, ambient air is fed upward through the paddy bed for the aeration. The initial moisture content of the paddy is around 12.8% wet basis. A mathematical model to predict the paddy bed temperature in the silo with the hybrid aeration-thermosyphon is developed, and the results agree very well with the experimental data. The operating period of its blower could be found from the simulation. The blower is on when the paddy bed temperature, T b , is over or equal to 28 deg. C and the difference temperature between the bed and the ambient, T d , is over or equal to 1 deg. C. The appropriate evaporator area should be over 8 m 2 . At the area of 8 m 2 , the operation time of the blower is 8-9% of the annual period compared with 30-40% for normal aeration alone. The monthly paddy bed temperature could be maintained between 24 and 27 deg. C under the climate of Chiang Mai, Thailand

  8. Air Distribution and Ventilation Effectiveness in a room with Floor/Ceiling Heating and Mixing/Displacement Ventilation

    DEFF Research Database (Denmark)

    Wu, Xiaozhou; Fang, Lei; Olesen, Bjarne W.

    2014-01-01

    vertical air temperature differences and air velocities for different hybrid systems are less than 3 C and 0.2 m/s when supply air temperature is 19 C, air change rate is 4.2 h-1, and heated surface temperature of floor/ceiling heating system is 25 C. Ventilation effectiveness of mixing ventilation system...... combined with floor/ceiling heating systems is approximately equal to 1.0, and ventilation effectiveness of displacement ventilation system combined with floor/ceiling heating systems ranges from 1.0 to 1.2. The floor/ceiling heating systems combined with mixing ventilation system have more uniform indoor...... air distribution but smaller ventilation effectiveness compared with the floor/ceiling heating systems combined with displacement ventilation system. With regard to the building heat loss increased by non-uniform indoor air distribution and small ventilation effectiveness, there should be an optimal...

  9. Southern company energy storage study :

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, James; Bhatnagar, Dhruv; Black, Clifton; Jenkins, Kip

    2013-03-01

    This study evaluates the business case for additional bulk electric energy storage in the Southern Company service territory for the year 2020. The model was used to examine how system operations are likely to change as additional storage is added. The storage resources were allowed to provide energy time shift, regulation reserve, and spinning reserve services. Several storage facilities, including pumped hydroelectric systems, flywheels, and bulk-scale batteries, were considered. These scenarios were tested against a range of sensitivities: three different natural gas price assumptions, a 15% decrease in coal-fired generation capacity, and a high renewable penetration (10% of total generation from wind energy). Only in the elevated natural gas price sensitivities did some of the additional bulk-scale storage projects appear justifiable on the basis of projected production cost savings. Enabling existing peak shaving hydroelectric plants to provide regulation and spinning reserve, however, is likely to provide savings that justify the project cost even at anticipated natural gas price levels. Transmission and distribution applications of storage were not examined in this study. Allowing new storage facilities to serve both bulk grid and transmission/distribution-level needs may provide for increased benefit streams, and thus make a stronger business case for additional storage.

  10. Heating, ventilating, and air-conditioning applications

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This book covers: Comfort air conditioning and heating of residences: Space HVAC systems; Industrial and special air conditioning and ventilation for nuclear facilities, and for mines; Energy sources, such as Geothermal energy, solar utilization, and energy resources; Building operation and maintenance; energy management, and Thermal storage

  11. Ventilation therapy for patients suffering from obstructive lung diseases.

    Science.gov (United States)

    Jungblut, Sven A; Heidelmann, Lena M; Westerfeld, Andreas; Frickmann, Hagen; Körber, Mareike K; Zautner, Andreas E

    2014-01-01

    Severe bronchial obstruction due to one of the major pulmonary diseases: asthma, COPD, or emphysema often requires mechanical ventilation support. Otherwise, patients are at risk of severe hypooxygenation with consecutive overloading and dilatation of the right cardiac ventricle with subsequent failure. This review focuses on how to manage a calculated ventilation therapy of patients suffering from bronchial obstruction and relevant patents. Options and pitfalls of invasive and non-invasive ventilation in the intensive care setting regarding clinical improvement and final outcome are discussed. The non-invasive ventilation is very efficient in treating acute or chronic respiratory failure in COPD patients and is capable of shortening the duration of hospitalization. Further non-invasive ventilation can successfully support the weaning after a long-lasting ventilation therapy and improve the prognosis of COPD patients. "Permissive hypercapnia" is unequivocally established in invasive ventilation therapy of severe bronchial obstruction in situations of limited ventilation. When intrinsic positive end-expiratory pressure (PEEP) and elevated airways resistance are present PEEP may be useful although external-PEEP application relieves over-inflation only in selected patients with airway obstruction during controlled mechanical ventilation. Upper limit of airways peak pressure used in "protective ventilation" of adult respiratory distress syndrome (ARDS) patients can be exceeded under certain circumstances.

  12. Clinical review: Humidifiers during non-invasive ventilation - key topics and practical implications

    Science.gov (United States)

    2012-01-01

    Inadequate gas conditioning during non-invasive ventilation (NIV) can impair the anatomy and function of nasal mucosa. The resulting symptoms may have a negative effect on patients' adherence to ventilatory treatment, especially for chronic use. Several parameters, mostly technical aspects of NIV, contribute to inefficient gas conditioning. Factors affecting airway humidity during NIV include inspiratory flow, inspiratory oxygen fraction, leaks, type of ventilator, interface used to deliver NIV, temperature and pressure of inhaled gas, and type of humidifier. The correct application of a humidification system may avoid the effects of NIV-induced drying of the airway. This brief review analyses the consequences of airway dryness in patients receiving NIV and the technical tools necessary to guarantee adequate gas conditioning during ventilatory treatment. Open questions remain about the timing of gas conditioning for acute or chronic settings, the choice and type of humidification device, the interaction between the humidifier and the underlying disease, and the effects of individual humidification systems on delivered humidity. PMID:22316078

  13. Ventilation System Strategy for a Prospective Korean Radioactive Waste Repository

    International Nuclear Information System (INIS)

    Kim, Jin; Kwon, Sang Ki

    2005-01-01

    In the stage of conceptual design for the construction and operation of the geologic repository for radioactive wastes, it is important to consider a repository ventilation system which serves the repository working environment, hygiene and safety of the public at large, and will allow safe maintenance like moisture content elimination in repository for the duration of the repositories life, construction/operation/closure, also allowing safe waste transportation and emplacement. This paper describes the possible ventilation system design criteria and requirements for the prospective Korean radioactive waste repositories with emphasis on the underground rock cavity disposal method in the both cases of low and medium-level and high-level wastes. It was found that the most important concept is separate ventilation systems for the construction (development) and waste emplacement (storage) activities. In addition, ventilation network system modeling, natural ventilation, ventilation monitoring systems and real time ventilation simulation, and fire simulation and emergency system in the repository are briefly discussed.

  14. Optimal Investment Planning of Bulk Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    Dina Khastieva

    2018-02-01

    Full Text Available Many countries have the ambition to increase the share of renewable sources in electricity generation. However, continuously varying renewable sources, such as wind power or solar energy, require that the power system can manage the variability and uncertainty of the power generation. One solution to increase flexibility of the system is to use various forms of energy storage, which can provide flexibility to the system at different time ranges and smooth the effect of variability of the renewable generation. In this paper, we investigate three questions connected to investment planning of energy storage systems. First, how the existing flexibility in the system will affect the need for energy storage investments. Second, how presence of energy storage will affect renewable generation expansion and affect electricity prices. Third, who should be responsible for energy storage investments planning. This paper proposes to assess these questions through two different mathematical models. The first model is designed for centralized investment planning and the second model deals with a decentralized investment approach where a single independent profit maximizing utility is responsible for energy storage investments. The models have been applied in various case studies with different generation mixes and flexibility levels. The results show that energy storage system is beneficial for power system operation. However, additional regulation should be considered to achieve optimal investment and allocation of energy storage.

  15. Continuous monitoring of natural ventilation pressure at the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Loomis, I.M.; Wallace, K.G.

    1993-01-01

    The Waste Isolation Pilot Plant (WIPP) is a US Department of Energy research and development facility designed to demonstrate the permanent, safe disposal of US defense-generated transuranic waste. The waste storage horizon is 655 m (2150 ft) below surface in bedded salt. To date the WIPP project has not emplaced any waste. There are three intake shafts used to supply air to the underground. All air is exhausted through a single return shaft. The total design airflow during normal operations is 200 m 3 /s (424,000 cfm). The ventilation system is designed to provide separate air splits to construction, experimental, and storage activities. Separation is achieved by isolating the storage circuit from the construction or experimental circuits with bulkheads. Any air leakage must be towards the storage area of the facility. Field studies have shown that the pressure differential necessary to maintain the correct leakage direction is susceptible to the effects of natural ventilation; therefore, extensive studies and analyses have been conducted to quantify the natural ventilation effects on the WIPP underground airflow system. A component of this work is a monitoring system designed to measure the air properties necessary for calculation of the natural ventilation pressure (NVP). This monitoring system consists of measuring dry bulb temperature, relative humidity, and barometric pressure at strategic location on surface and underground. The psychometric parameters of the air are measured every fifteen minutes. From these data, trends can be determined showing the impact of NVP on the ventilation system during diurnal variations in surface climate. Both summer and winter conditions have been studied. To the author's knowledge this is the first reported instance of automatic and continuous production of time and temperature variant NVPs. This paper describes the results of the initial monitoring study

  16. An integrated approach to risk-based remediation of a former bulk fuel storage facility adjacent a marine environment

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, L.; Hers, I. [Golder Associates Ltd., Vancouver, BC (Canada)

    2006-07-01

    An integrated approach to risk-based remediation of a former bulk fuel storage facility adjacent to a marine environment was discussed. The presentation provided an introduction and illustration to the site location and history, located close to Skagway, Alaska and northwestern British Columbia. The site investigation and conceptual model were also presented. The remedial approach was also described with reference to a risk-based action approach, remedial objectives, soil vapour extraction (SVE)-bioventing, and air sparging-biosparging. The objectives were to minimize potential exposure to aquatic receptors by minimizing non-aqueous phase liquids (NAPL) mobility and dissolved transport of petroleum hydrocarbons. Groundwater modeling to assess the attenuation rate and to determine remedial targets was also discussed. Model validation and results of groundwater modeling as well as remediation system details and performance were then provided. It was determined that significant attenuation is occurring and that effective mass removal and concentrations have been decreasing over time. It was demonstrated that risk-based remedial goals and hydrogeology can change with land use/development. tabs., figs.

  17. 46 CFR 28.340 - Ventilation of enclosed engine and fuel tank spaces.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Ventilation of enclosed engine and fuel tank spaces. 28... of enclosed engine and fuel tank spaces. (a) Applicability. Each vessel with a gasoline outboard engine or gasoline storage tank must comply with the requirements of this section. (b) Ventilation of...

  18. Phase change materials in non-volatile storage

    OpenAIRE

    Ielmini, Daniele; Lacaita, Andrea L.

    2011-01-01

    After revolutionizing the technology of optical data storage, phase change materials are being adopted in non-volatile semiconductor memories. Their success in electronic storage is mostly due to the unique properties of the amorphous state where carrier transport phenomena and thermally-induced phase change cooperate to enable high-speed, low-voltage operation and stable data retention possible within the same material. This paper reviews the key physical properties that make this phase so s...

  19. Mechanical ventilation during extracorporeal membrane oxygenation.

    Science.gov (United States)

    Schmidt, Matthieu; Pellegrino, Vincent; Combes, Alain; Scheinkestel, Carlos; Cooper, D Jamie; Hodgson, Carol

    2014-01-21

    The timing of extracorporeal membrane oxygenation (ECMO) initiation and its outcome in the management of respiratory and cardiac failure have received considerable attention, but very little attention has been given to mechanical ventilation during ECMO. Mechanical ventilation settings in non-ECMO studies have been shown to have an effect on survival and may also have contributed to a treatment effect in ECMO trials. Protective lung ventilation strategies established for non-ECMO-supported respiratory failure patients may not be optimal for more severe forms of respiratory failure requiring ECMO support. The influence of positive end-expiratory pressure on the reduction of the left ventricular compliance may be a matter of concern for patients receiving ECMO support for cardiac failure. The objectives of this review were to describe potential mechanisms for lung injury during ECMO for respiratory or cardiac failure, to assess the possible benefits from the use of ultra-protective lung ventilation strategies and to review published guidelines and expert opinions available on mechanical ventilation-specific management of patients requiring ECMO, including mode and ventilator settings. Articles were identified through a detailed search of PubMed, Ovid, Cochrane databases and Google Scholar. Additional references were retrieved from the selected studies. Growing evidence suggests that mechanical ventilation settings are important in ECMO patients to minimize further lung damage and improve outcomes. An ultra-protective ventilation strategy may be optimal for mechanical ventilation during ECMO for respiratory failure. The effects of airway pressure on right and left ventricular afterload should be considered during venoarterial ECMO support of cardiac failure. Future studies are needed to better understand the potential impact of invasive mechanical ventilation modes and settings on outcomes.

  20. Oral appliance to assist non-invasive ventilation in a patient with amyotrophic lateral sclerosis.

    Science.gov (United States)

    Veldhuis, Steffanie K B; Doff, Michiel H J; Stegenga, Boudewijn; Nieuwenhuis, Jellie A; Wijkstra, Peter J

    2015-03-01

    From the moment the respiratory muscle groups are affected in amyotrophic lateral sclerosis (ALS), respiratory complications will be the major cause of morbidity and mortality. Untreated respiratory muscle impairment leads to respiratory insufficiency and additionally to difficulties in airway secretion clearance. Non-invasive ventilation (NIV) is the first choice in treating respiratory insufficiency in ALS as it improves sleep-related symptoms, quality of life and life expectancy. Nevertheless, NIV is not always effective, probably due to bulbar dysfunction or anatomical abnormalities. As a result, tracheostomy ventilation (TV) may become necessary. In this case report, we present a 60-year-old female with ALS, for whom it was not possible to provide a sufficient tidal volume with NIV. A chin lift was performed while the patient was awake to see if a more anterior jaw position would lead to an increased tidal volume. As this was the case, a mandibular advancement device (MAD) was fabricated. With a combination of a MAD and NIV, the upper airway obstructions were overcome and a good ventilation and adherence to therapy were seen. When there is the presumption of airway obstructions in combination with an ineffective NIV, we advise to perform a chin lift to assess whether the obstructions can be overcome by a more anterior jaw position. If that is the case, NIV may be combined with MAD to establish effective ventilation and avoid the use of TV.

  1. 3 Level Ventilation: the First Clinical Experience

    Directory of Open Access Journals (Sweden)

    P. Torok

    2008-01-01

    Full Text Available Considering the issues of artificial ventilation (AV in non-homogenous pathological lung processes (acute lung injury (ALI, acute respiratory distress syndrome (ARDS, pneumonia, etc., the authors applied the three-level lung ventilation to a group of 12 patients with non-homogenous lung injury. Three-level ventilation was defined as a type (modification of AV whose basic ventilation level was produced by the modes CMV, PCV or PS (ASB and add-on level, the so-called background ventilation was generated by two levels of PEEP. PEEP (constant and PEEPh (PEEP high with varying frequency and duration of transition between the individual levels of PEEP. Objective: to elucidate whether in cases of considerably non-homogenous gas distribution in acute pathological disorders, three-level ventilation (3LV can correct gas distribution into the so-called slow bronchoalveolar compartments, by decreasing the volume load of the so-called fast compartments and to improve lung gas exchange, by following the principles of safe ventilation. Results. 3LV was applied to 12 patients with severe non-homogenous lung injury/disorder (atypic pneumonia and ARDS/ALI and low-success PCV ventilation after recruitment manoeuvre (PaO2 (kPA /FiO2 = 5—6. There were pronounced positive changes in pulmonary gas exchange within 1—4 hours after initiation of 3LV at a fPCV of 26±4 breaths/min-1 and PEEPh at a fPEEPH of 7±2 breaths/min-1 with a minute ventilation of 12±4 l/min. 3LV reduced a intrapulmonary shunt fraction 50±5 to 30±5%, increased CO2 elimination, with PaCO2 falling to the values below 6±0.3 kPa, and PaO2 to 7.5±1.2 kPa, with FiO2 being decreased to 0.8—0.4. Lung recruitment also improved gas exchange: with PEEP=1.2±0.4 kPa, static tho-racopulmonary compliance (Cst elevated from 0.18±0.02 l/kPa to 0.3±0.02 l/kPa and then to 0.38±0.05 l/kPa. Airways resistance (Raw decreased by more than 30%. Improved lung aeration was also estimated as a manifestation of

  2. Standardization of pulmonary ventilation technique using volume-controlled ventilators in rats with congenital diaphragmatic hernia

    Directory of Open Access Journals (Sweden)

    Rodrigo Melo Gallindo

    Full Text Available OBJECTIVE: To standardize a technique for ventilating rat fetuses with Congenital Diaphragmatic Hernia (CDH using a volume-controlled ventilator. METHODS: Pregnant rats were divided into the following groups: a control (C; b exposed to nitrofen with CDH (CDH; and c exposed to nitrofen without CDH (N-. Fetuses of the three groups were randomly divided into the subgroups ventilated (V and non-ventilated (N-V. Fetuses were collected on day 21.5 of gestation, weighed and ventilated for 30 minutes using a volume-controlled ventilator. Then the lungs were collected for histological study. We evaluated: body weight (BW, total lung weight (TLW, left lung weight (LLW, ratios TLW / BW and LLW / BW, morphological histology of the airways and causes of failures of ventilation. RESULTS: BW, TLW, LLW, TLW / BW and LLW / BW were higher in C compared with N- (p 0.05. The morphology of the pulmonary airways showed hypoplasia in groups N- and CDH, with no difference between V and N-V (p <0.05. The C and N- groups could be successfully ventilated using a tidal volume of 75 ìl, but the failure of ventilation in the CDH group decreased only when ventilated with 50 ìl. CONCLUSION: Volume ventilation is possible in rats with CDH for a short period and does not alter fetal or lung morphology.

  3. Mechanical ventilation using non-injurious ventilation settings causes lung injury in the absence of pre-existing lung injury in healthy mice

    NARCIS (Netherlands)

    Wolthuis, Esther K; Vlaar, Alexander P J; Choi, Goda; Roelofs, Joris J T H; Juffermans, Nicole P; Schultz, Marcus J

    2009-01-01

    INTRODUCTION: Mechanical ventilation (MV) may cause ventilator-induced lung injury (VILI). Present models of VILI use exceptionally large tidal volumes, causing gross lung injury and haemodynamic shock. In addition, animals are ventilated for a relative short period of time and only after a

  4. Non-invasive mechanical ventilation in internal medicine departments: a pilot study

    Directory of Open Access Journals (Sweden)

    Micaela La Regina

    2013-09-01

    Full Text Available Non-invasive mechanical ventilation (NIMV has been shown to be an effective treatment in chronic and acute lung failure. Until a few years ago, all the different forms of mechanical ventilation were managed exclusively in intensive care units (ICU. However, the reduction in the number of ICU beds available and the high costs involved in running such units, together with the aging of the general population and the co-morbidities associated with this have meant that forms of mechanical ventilation are also used outside ICUs. In addition to emergency physicians and pneumologists, also internists have started to use NIMV on their wards in order to start treatment as early as possible and reduce costs. This is a preliminary study to explore the effectiveness, safety and feasibility of NIMV on a medical ward. The overall success rate was 68.8%; the likelihood of success was higher in patients who started NIMV earlier. The success rate was quite high (62% also among do-not-intubate patients, despite their poorer clinical condition. Few complications were reported and there was no increase in staff workload. No significant differences were found in in-hospital mortality between hypercapnic patients with chronic obstructive pulmonary disease (COPD exacerbation and hypercapnic patients with COPD plus pneumonia (27% vs 25% or between patients with pneumonia and patients with COPD plus pneumonia (26% vs 25%. These results are encouraging for the successful use of NIMV on medical wards. A careful selection of patients, educating and motivating staff in NIMV use, and close collaboration with resuscitators are all essential for this to be achieved.

  5. Mechanical ventilation using non-injurious ventilation settings causes lung injury in the absence of pre-existing lung injury in healthy mice

    NARCIS (Netherlands)

    Wolthuis, Esther K.; Vlaar, Alexander Pj; Choi, Goda; Roelofs, Joris J. T. H.; Juffermans, Nicole P.; Schultz, Marcus J.

    2009-01-01

    Introduction Mechanical ventilation (MV) may cause ventilator-induced lung injury (VILI). Present models of VILI use exceptionally large tidal volumes, causing gross lung injury and haemodynamic shock. In addition, animals are ventilated for a relative short period of time and only after a 'priming'

  6. Static Properties of Superconductor Journal Bearing Substator for Superconductor Flywheel Energy Storage System

    International Nuclear Information System (INIS)

    Park, B. J.; Jung, S. Y.; Lee, J. P.; Park, B. C.; Jeong, N. H.; Sung, T. H.; Han, Y. H.

    2008-01-01

    A Superconductor Flywheel Energy Storage System(SFES) mainly consists of a pair of non-contacting High Temperature Superconductor(HTS) bearings that provide very low frictional losses, a composite flywheel with high energy storage density. The HTS bearings, which offer dynamic stability without active control, are the key technology that distinguishes the SFES from other flywheel energy storage devices, and great effort is being put into developing this technology. The Superconductor Journal Bearing(SJB) mainly consists of HTS bulks and a stator, which holds the HTS bulks and also acts as a cold head. Static properties of HTS bearings provide data to solve problems which may occur easily in a running system. Since stiffness to counter vibration is the main parameter in designing an HTS bearing system, we investigate SJB magnetic force through static properties between the Permanent Magnet(PM) and HTS. We measure stiffness in static condition and the results are used to determine the optimal number of HTS bulks for a 100kWh SFES.

  7. Non-linearities in Holocene floodplain sediment storage

    Science.gov (United States)

    Notebaert, Bastiaan; Nils, Broothaerts; Jean-François, Berger; Gert, Verstraeten

    2013-04-01

    Floodplain sediment storage is an important part of the sediment cascade model, buffering sediment delivery between hillslopes and oceans, which is hitherto not fully quantified in contrast to other global sediment budget components. Quantification and dating of floodplain sediment storage is data and financially demanding, limiting contemporary estimates for larger spatial units to simple linear extrapolations from a number of smaller catchments. In this paper we will present non-linearities in both space and time for floodplain sediment budgets in three different catchments. Holocene floodplain sediments of the Dijle catchment in the Belgian loess region, show a clear distinction between morphological stages: early Holocene peat accumulation, followed by mineral floodplain aggradation from the start of the agricultural period on. Contrary to previous assumptions, detailed dating of this morphological change at different shows an important non-linearity in geomorphologic changes of the floodplain, both between and within cross sections. A second example comes from the Pre-Alpine French Valdaine region, where non-linearities and complex system behavior exists between (temporal) patterns of soil erosion and floodplain sediment deposition. In this region Holocene floodplain deposition is characterized by different cut-and-fill phases. The quantification of these different phases shows a complicated image of increasing and decreasing floodplain sediment storage, which hampers the image of increasing sediment accumulation over time. Although fill stages may correspond with large quantities of deposited sediment and traditionally calculated sedimentation rates for such stages are high, they do not necessary correspond with a long-term net increase in floodplain deposition. A third example is based on the floodplain sediment storage in the Amblève catchment, located in the Belgian Ardennes uplands. Detailed floodplain sediment quantification for this catchments shows

  8. Ventilation

    DEFF Research Database (Denmark)

    Nielsen, Toke Rammer; Svendsen, Sv Aa Højgaard

    1999-01-01

    The note concerns ventilation in residential buildings. Describes components in ventilation systems, electric energy consumption and different ventilation systems with heat exchanger.......The note concerns ventilation in residential buildings. Describes components in ventilation systems, electric energy consumption and different ventilation systems with heat exchanger....

  9. : ventilators for noninvasive ventilation

    OpenAIRE

    Fauroux , Brigitte; Leroux , Karl; Desmarais , Gilbert; Isabey , Daniel; Clément , Annick; Lofaso , Frédéric; Louis , Bruno

    2008-01-01

    International audience; The aim of the present study was to evaluate the performance characteristics of all the ventilators proposed for home noninvasive positive-pressure ventilation in children in France. The ventilators (one volume-targeted, 12 pressure-targeted and four dual) were evaluated on a bench which simulated six different paediatric ventilatory patterns. For each ventilator, the quality of the inspiratory and expiratory trigger and the ability to reach and maintain the preset pre...

  10. Liquid ventilation.

    Science.gov (United States)

    Sarkar, Suman; Paswan, Anil; Prakas, S

    2014-01-01

    Human have lungs to breathe air and they have no gills to breath liquids like fish. When the surface tension at the air-liquid interface of the lung increases as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen as the inert carrier of oxygen and carbon dioxide offers a number of advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. It is well-known that respiratory diseases are one of the most common causes of morbidity and mortality in intensive care unit. During the past few years several new modalities of treatment have been introduced. One of them and probably the most fascinating, is of LV. Partial LV, on which much of the existing research has concentrated, requires partial filling of lungs with perfluorocarbons (PFC's) and ventilation with gas tidal volumes using conventional mechanical ventilators. Various physico-chemical properties of PFC's make them the ideal media. It results in a dramatic improvement in lung compliance and oxygenation and decline in mean airway pressure and oxygen requirements. No long-term side-effect reported.

  11. Long-term follow-up of otitis media with effusion in children: comparisons between a ventilation tube group and a non-ventilation tube group.

    Science.gov (United States)

    Hong, Hye Ran; Kim, Tae Su; Chung, Jong Woo

    2014-06-01

    The objective of this study was to investigate the long-term outcomes in children with otitis media with effusion who received either medical treatment or ventilation tubes. We retrospectively analyzed the medical records of 89 bilateral cases of otitis media with effusion in children who were recommended to receive ventilation tube insertion and were followed up for more than 5 years. Tympanic membrane was inspected by otoscopic examination. Hearing was evaluated with pure tone audiometry. The mean duration of follow-up was 8.4 years (range, 5.2-15.7 years). Twenty-three children were treated without surgery, while 22 were treated once by ventilation tube insertion and 44 were treated more than once by ventilation tube insertion. At the fifth year of follow-up, both groups of children who underwent ventilation tube insertion had more frequent tympanic membrane abnormalities than the medication group (8.7% in those treated without surgery, 72.7% in those treated once by ventilation tube insertion, and 88.6% in those treated more than once by ventilation tube insertion). Common tympanic membrane abnormalities were retraction (27.0%) and tympanosclerotic plaque (23.6%), regardless of the treatment modality. At the fifth year follow-up, the average air-conduction threshold was 10.0 dB (± 6.5 dB) in patients treated without surgery, 15.9 dB (± 11.2dB) in patients treated once by ventilation tube insertion, and 17.8 dB (± 7.6 dB) in those treated more than once by ventilation tube insertion. The audiological difference was significant when we compared the hearing level of children treated by medication without surgery to the two ventilation tube groups. Though ventilation tube insertion can resolve hearing loss quickly, there were more tympanic membrane abnormalities and a decline in hearing levels in our ventilation tube insertion group vs. the observation group measured 5 years later. Physicians should therefore be cautious when applying a ventilation tube in

  12. Non-invasive ventilation in severe asthma attack, its possibilities and problems.

    Science.gov (United States)

    Murase, K; Tomii, K; Chin, K; Niimi, A; Ishihara, K; Mishima, M

    2011-06-01

    Asthma attack is characterized by episodic attacks of cough, dyspnea and wheeze occurring due to bronchoconstriction, airway hyperresponsiveness and mucous hypersecretion. Although nationwide clinical guidelines have been published to establish the standard care of asthma, choices in the treatment of fatal asthma attacks remain of clinical significance. Especially, in a severe asthma attack, despite the application of conventional medical treatment, respiratory management is critical. Even though non-invasive ventilation (NIV) has been shown to be effective in a wide variety of clinical settings, reports of NIV in asthmatic patients are scarce. According to a few prospective clinical trials reporting promising results in favour of the use of NIV in a severe asthma attack, a trial of NIV prior to invasive mechanical ventilation seems acceptable and may benefit patients by decreasing the need for intubation and by supporting pharmaceutical treatments. Although selecting the appropriate patients for NIV use is a key factor in successful NIV application, how to distinguish such patients is quite controversial. Larger high quality clinical trails are urgently required to confirm the benefits of NIV to patients with severe asthma attack. In this article, we focus on the body of evidence supporting the use of NIV in asthma attacks and discuss its advantages as well its problems.

  13. Respiratory polygraphy monitoring of intensive care patients receiving non-invasive ventilation

    Directory of Open Access Journals (Sweden)

    Eduardo Borsini

    Full Text Available Introduction: Patients that started on Non-Invasive Ventilation (NIV need to define several parameters selected on the basis of diurnal arterial blood gas and underlying disease. We hypothesize that respiratory polygraphy (RP could be useful to monitor NIV. This retrospective work describes RP findings and their impact on the setting of continuous flow ventilators from patients on NIV of Intensive Care Unit (ICU. Material and Methods: Patient's data on NIV from at the ICU of Hospital Británico were included in this study. RP recordings were performed in all of them. Respiratory events, such as ventilatory pattern changes, impact on oximetry or tidal volume, were observed to modify the ventilatory mode after RP. Results: The RP findings have contributes to change the ventilatory mode for one third of the patients. The mean values of expiratory positive airway pressure (EPAP and inspiratory positive airway pressure (IPAP were not significantly different across all the population before or after RP: 8.7±0.3 vs. 8.6±0.4; p 2 cmH2O pressure value changes after RP. Conclusions: RP recordings could contribute to broad range of data useful to make decisions about changes in programming and allowed to identify adverse events related to positive pressure.

  14. Ventilation of an hydrofoil wake

    Science.gov (United States)

    Arndt, Roger; Lee, Seung Jae; Monson, Garrett

    2013-11-01

    Ventilation physics plays a role in a variety of important engineering applications. For example, hydroturbine ventilation is used for control of vibration and cavitation erosion and more recently for improving the dissolved oxygen content of the flow through the turbine. The latter technology has been the focus of an ongoing study involving the ventilation of an hydrofoil wake to determine the velocity and size distribution of bubbles in a bubbly wake. This was carried out by utilizing particle shadow velocimetry (PSV). This technique is a non-scattering approach that relies on direct in-line volume illumination by a pulsed source such as a light-emitting diode (LED). The data are compared with previous studies of ventilated flow. The theoretical results of Hinze suggest that a scaling relationship is possible that can lead to developing appropriate design parameters for a ventilation system. Sponsored by ONR and DOE.

  15. Thermal analysis of a ventilated high-level waste repository

    International Nuclear Information System (INIS)

    1977-04-01

    The cooling response of a single ventilated storage room in an unventilated array of rooms is examined. Calculations show that ventilation provides a thermal sink in the heated system inducing temperature gradients in the formation different from the unventilated case. An asymptotic cool-down limit exists for the storage room temperature; this minimum temperature depends on inlet air temperature, ventilation flow rate, and convective heat transfer coefficient. For inlet air at 75 0 F and 50,000 cfm and a heat transfer coefficient of 0.8 Btu h- 0 F-ft 2 , the limit is about 100 0 F. A storage room sealed for 5 years will achieve temperatures of approximately 180 0 F, and approximately 4 months would be required in order to cool the storage room floor to a temperature of 120 0 F with a flow rate of 50,000 cfm at an inlet air temperature of 75 0 F, assuming a convective heat transfer coefficient of 0.8 Btu/h- 0 F-ft 2 . Two months would be needed to cool the exhaust air to 120 0 F. For large air flow rates, the cooling time is independent of the flow rate. Increasing the storage room surface area by 25% over the baseline model depresses the cool-down temperatures by only 4 0 F and decreases cooling times by 20%. Modifications in canister design or width have virtually no effect on the cooling, but placing the waste deeper beneath the storage rooms and/or using longer canisters can lower the operating temperatures and cooling times. Reducing the canisters from 3.5 kW power density for 10-year-old waste (108.5 kW/acre) to 2.0 kW/canister (62 kW/acre) reduces cooling temperatures by more than 20 0 F and reduces cooling times to a few weeks or less. The cooling times are nearly independent of the conductivity of the geologic formation. The temperature increase in the air brought from the surface down the supply shaft to the storage room level is about 5 to 7 F 0 per 1000 feet. Temperature increases in regionsshould not be seriously restricted 30 or more feet away

  16. Air quality in low-ventilated museum storage buildings

    DEFF Research Database (Denmark)

    Ryhl-Svendsen, Morten; Aasbjerg Jensen, Lars; Klenz Larsen, Poul

    2014-01-01

    Modern low-energy museum storage buildings are often designed for a low air exchange rate, on the order of less than 1 exchange per day. We investigated how this affected the indoor air quality in six Danish museum storage buildings. The infiltration of ambient pollutants, and the level to which...... internally-generated pollutants accumulate, were measured by passive sampling of ozone, nitrogen dioxide, and organic acids. The air exchange rates and the interchange of air between storage rooms were measured by the per-fluorocarbon tracer gas method. Ambient pollutants were reduced in concentration...

  17. Ventilation system in the RA reactor building - design specifications

    International Nuclear Information System (INIS)

    Badrljica, R.

    1984-09-01

    Protective role of the ventilation system of nuclear facilities involve construction of ventilation barriers which prevent release of radioactive particulates or gases, elimination od radioactive particulates and gases from the air which is released from contaminated zones into the reactor environment. Ventilation barriers are created by dividing the building into a number of ventilation zones with different sub pressure compared to the atmospheric pressure. The RA reactor building is divided into four ventilation zones. First zone is the zone of highest risk. It includes reactor core with horizontal experimental channels, underground rooms of the primary coolant system (D 2 O), helium system, hot cells and the space above the the reactor core. Second zone is the reactor hall and the room for irradiated fuel storage. The third zone includes corridors in the basement, ground floor and first floor where the probability of contamination is small. The fourth zone includes the annex where the contamination risk is low. There is no have natural air circulation in the reactor building. Ventilators for air input and outlet maintain the sub pressure in the building (pressure lower than the atmospheric pressure). This prevents release of radioactivity into the atmosphere [sr

  18. Role of First-Line Noninvasive Ventilation in Non-COPD Subjects With Pneumonia.

    Science.gov (United States)

    Rialp, Gemma; Forteza, Catalina; Muñiz, Daniel; Romero, Maria

    2017-09-01

    The use of noninvasive ventilation (NIV) in non-COPD patients with pneumonia is controversial due to its high rate of failure and the potentially harmful effects when NIV fails. The purpose of the study was to evaluate outcomes of the first ventilatory treatment applied, NIV or invasive mechanical ventilation (MV), and to identify predictors of NIV failure. Historical cohort study of 159 non-COPD patients with pneumonia admitted to the ICU with ventilatory support. Subjects were divided into 2 groups: invasive MV or NIV. Univariate and multivariate analyses with demographic and clinical data were performed. Analysis of mortality was adjusted for the propensity of receiving first-line invasive MV. One hundred and thirteen subjects received first-line invasive MV and 46 received first-line NIV, of which 27 needed intubation. Hospital mortality was 35, 37 and 56%, respectively, with no significant differences among groups. In the propensity-adjusted analysis (expressed as OR [95% CI]), hospital mortality was associated with age (1.05 [1.02-1.08]), SAPS3 (1.03 [1.00-1.07]), immunosuppression (2.52 [1.02-6.27]) and NIV failure compared to first-line invasive MV (4.3 [1.33-13.94]). Compared with invasive MV, NIV failure delayed intubation (p=.004), and prolonged the length of invasive MV (p=.007) and ICU stay (p=.001). NIV failure was associated with need for vasoactive drugs (OR 7.8 [95% CI, 1.8-33.2], p=.006). In non-COPD subjects with pneumonia, first-line NIV was not associated with better outcome compared with first-line invasive MV. NIV failure was associated with longer duration of MV and hospital stay, and with increased hospital mortality. The use of vasoactive drugs predicted NIV failure. Copyright © 2016 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Multifaceted bench comparative evaluation of latest intensive care unit ventilators.

    Science.gov (United States)

    Garnier, M; Quesnel, C; Fulgencio, J-P; Degrain, M; Carteaux, G; Bonnet, F; Similowski, T; Demoule, A

    2015-07-01

    Independent bench studies using specific ventilation scenarios allow testing of the performance of ventilators in conditions similar to clinical settings. The aims of this study were to determine the accuracy of the latest generation ventilators to deliver chosen parameters in various typical conditions and to provide clinicians with a comprehensive report on their performance. Thirteen modern intensive care unit ventilators were evaluated on the ASL5000 test lung with and without leakage for: (i) accuracy to deliver exact tidal volume (VT) and PEEP in assist-control ventilation (ACV); (ii) performance of trigger and pressurization in pressure support ventilation (PSV); and (iii) quality of non-invasive ventilation algorithms. In ACV, only six ventilators delivered an accurate VT and nine an accurate PEEP. Eleven devices failed to compensate VT and four the PEEP in leakage conditions. Inspiratory delays differed significantly among ventilators in invasive PSV (range 75-149 ms, P=0.03) and non-invasive PSV (range 78-165 ms, Pventilation algorithms efficiently prevented the decrease in pressurization capacities and PEEP levels induced by leaks in, respectively, 10 and 12 out of the 13 ventilators. We observed real heterogeneity of performance amongst the latest generation of intensive care unit ventilators. Although non-invasive ventilation algorithms appear to maintain adequate pressurization efficiently in the case of leakage, basic functions, such as delivered VT in ACV and pressurization in PSV, are often less reliable than the values displayed by the device suggest. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Non-sedation versus sedation with a daily wake-up trial in critically ill patients receiving mechanical ventilation (NONSEDA Trial)

    DEFF Research Database (Denmark)

    Toft, Palle; Olsen, Hanne Tanghus; Jørgensen, Helene Korvenius

    2014-01-01

    comparing sedation with no sedation, a priori powered to have all-cause mortality as primary outcome.The objective is to assess the benefits and harms of non-sedation versus sedation with a daily wake-up trial in critically ill patients. METHODS: The non-sedation (NONSEDA) trial is an investigator......-sedation supplemented with pain management during mechanical ventilation.Control intervention is sedation with a daily wake-up trial.The primary outcome will be all cause mortality at 90 days after randomization. Secondary outcomes will be: days until death throughout the total observation period; coma- and delirium...... in mortality with a type I error risk of 5% and a type II error risk of 20% (power at 80%). DISCUSSION: The trial investigates potential benefits of non-sedation. This might have large impact on the future treatment of mechanically ventilated critically ill patients.Trial register: ClinicalTrials.gov NCT...

  1. Application of 3C insulin pump system in combination with non-invasive ventilation in the treatment of a patient with type 2 diabetes and obstructive sleep apnea syndrome.

    Science.gov (United States)

    Dong, Peng; Xu, Jing; Wang, Junhong; Zhang, Chunhong

    2018-03-01

    We observed the curative effect of the 3C insulin system in combination with non-invasive ventilation in a patient with type 2 diabetes and obstructive sleep apnea syndrome (OSAS). The 3C insulin pump is a system of devices that closely monitors and effectively regulates blood glucose levels. Non-invasive ventilation has been shown to be an effective treatment for OSAS. A type 2 diabetes patient with concomitant OSAS was treated with a 3C insulin pump system for real-time continuous glucose monitoring and nocturnal non-invasive ventilation for OSAS. Treatment-induced diabetic remission with improved sleep and reduced hypoglycemic episodes was achieved. Therefore, the 3C insulin pump system, in combination with non-invasive ventilation, is an effective treatment for type 2 diabetes patients with concomitant OSAS. © 2017 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

  2. Clinical review: Helmet and non-invasive mechanical ventilation in critically ill patients.

    Science.gov (United States)

    Esquinas Rodriguez, Antonio M; Papadakos, Peter J; Carron, Michele; Cosentini, Roberto; Chiumello, Davide

    2013-04-25

    Non-invasive mechanical ventilation (NIV) has proved to be an excellent technique in selected critically ill patients with different forms of acute respiratory failure. However, NIV can fail on account of the severity of the disease and technical problems, particularly at the interface. The helmet could be an alternative interface compared to face mask to improve NIV success. We performed a clinical review to investigate the main physiological and clinical studies assessing the efficacy and related issues of NIV delivered with a helmet. A computerized search strategy of MEDLINE/PubMed (January 2000 to May 2012) and EMBASE (January 2000 to May 2012) was conducted limiting the search to retrospective, prospective, nonrandomized and randomized trials. We analyzed 152 studies from which 33 were selected, 12 physiological and 21 clinical (879 patients). The physiological studies showed that NIV with helmet could predispose to CO₂ rebreathing and increase the patients' ventilator asynchrony. The main indications for NIV were acute cardiogenic pulmonary edema, hypoxemic acute respiratory failure (community-acquired pneumonia, postoperative and immunocompromised patients) and hypercapnic acute respiratory failure. In 9 of the 21 studies the helmet was compared to a face mask during either continous positive airway pressure or pressure support ventilation. In eight studies oxygenation was similar in the two groups, while the intubation rate was similar in four and lower in three studies for the helmet group compared to face mask group. The outcome was similar in six studies. The tolerance was better with the helmet in six of the studies. Although these data are limited, NIV delivered by helmet could be a safe alternative to the face mask in patients with acute respiratory failure.

  3. Numerical study on the thermal performance of a ventilated facade with PCM

    International Nuclear Information System (INIS)

    Gracia, Alvaro de; Navarro, Lidia; Castell, Albert; Cabeza, Luisa F.

    2013-01-01

    A new type of ventilated facade (VF) with macro-encapsulated phase change material (PCM) in its air cavity is presented in this paper. Two identical house-like cubicles located in Puigverd de Lleida (Spain) were monitored during 2012, and in one of them, the VF with PCM was implemented in the south wall. The versatility of the facade allows the system to reduce both heating and cooling loads. During winter, the PCM increases the heat storage capacity of the system exposed to solar radiation and during summer the system can be used as a cold storage unit or as a night free cooling device. From the experimental winter campaign, important net electrical energy savings were registered due to the use of the VF. On the other hand, no net energy savings were achieved during summer due to excessive use of mechanical ventilation. In this paper, an own developed numerical model, based on finite control volume approach, was validated against experimental data and it is used to select the operational schedule of both solidification and melting processes in order to achieve net electrical energy savings. During the mild summer period the system presents a net energy supply of 2.49 MJ/day. This value would be increased by 61.6% if a wooden structure would have been used instead of the current metallic structure. Moreover, the high hysteresis of the PCM limits strongly the potential of the system in supplying cooling during the severe summer period. -- Highlights: • Numerical study of the thermal performance of a ventilated facade with PCM. • The study considers cooling purposes. • Operational schedule and use of fans during solidification of PCM optimization. • Net energy supply of 2.49 MJ/day during mild summer from the ventilated facade. • Storage efficiency would maximize with more mechanical ventilation during less time

  4. Comparative performances analysis of neonatal ventilators.

    Science.gov (United States)

    Baldoli, Ilaria; Tognarelli, Selene; Scaramuzzo, Rosa T; Ciantelli, Massimiliano; Cecchi, Francesca; Gentile, Marzia; Sigali, Emilio; Ghirri, Paolo; Boldrini, Antonio; Menciassi, Arianna; Laschi, Cecilia; Cuttano, Armando

    2015-02-08

    Mechanical ventilation is a therapeutic action for newborns with respiratory diseases but may have side effects. Correct equipment knowledge and training may limit human errors. We aimed to test different neonatal mechanical ventilators' performances by an acquisition module (a commercial pressure sensor plus an isolated chamber and a dedicated software). The differences (ΔP) between peak pressure values and end-expiration pressure were investigated for each ventilator. We focused on discrepancies among measured and imposed pressure data. A statistical analysis was performed. We investigated the measured/imposed ΔP relation. The ΔP do not reveal univocal trends related to ventilation setting parameters and the data distributions were non-Gaussian. Measured ΔP represent a significant parameter in newborns' ventilation, due to the typical small volumes. The investigated ventilators showed different tendencies. Therefore, a deep specific knowledge of the intensive care devices is mandatory for caregivers to correctly exploit their operating principles.

  5. Non-contrast-enhanced perfusion and ventilation assessment of the human lung by means of fourier decomposition in proton MRI.

    Science.gov (United States)

    Bauman, Grzegorz; Puderbach, Michael; Deimling, Michael; Jellus, Vladimir; Chefd'hotel, Christophe; Dinkel, Julien; Hintze, Christian; Kauczor, Hans-Ulrich; Schad, Lothar R

    2009-09-01

    Assessment of regional lung perfusion and ventilation has significant clinical value for the diagnosis and follow-up of pulmonary diseases. In this work a new method of non-contrast-enhanced functional lung MRI (not dependent on intravenous or inhalative contrast agents) is proposed. A two-dimensional (2D) true fast imaging with steady precession (TrueFISP) pulse sequence (TR/TE = 1.9 ms/0.8 ms, acquisition time [TA] = 112 ms/image) was implemented on a 1.5T whole-body MR scanner. The imaging protocol comprised sets of 198 lung images acquired with an imaging rate of 3.33 images/s in coronal and sagittal view. No electrocardiogram (ECG) or respiratory triggering was used. A nonrigid image registration algorithm was applied to compensate for respiratory motion. Rapid data acquisition allowed observing intensity changes in corresponding lung areas with respect to the cardiac and respiratory frequencies. After a Fourier analysis along the time domain, two spectral lines corresponding to both frequencies were used to calculate the perfusion- and ventilation-weighted images. The described method was applied in preliminary studies on volunteers and patients showing clinical relevance to obtain non-contrast-enhanced perfusion and ventilation data.

  6. Ventilation practices in subarachnoid hemorrhage: a cohort study exploring the use of lung protective ventilation.

    Science.gov (United States)

    Marhong, Jonathan D; Ferguson, Niall D; Singh, Jeffrey M

    2014-10-01

    Acute respiratory distress syndrome (ARDS) is common following aneurysmal subarachnoid hemorrhage (SAH), but the influence of mechanical ventilator settings on its development is unclear. We sought to determine adherence to lung protective thresholds in ventilated patients with SAH and describe the association between ventilator settings and subsequent development of ARDS. We conducted a retrospective cohort study of consecutive patients receiving mechanical ventilation within 72 h of SAH at a single academic center. Ventilator settings and blood gas data were collected twice daily for the first 7 days of ventilation along with ICU and hospital outcomes. Lung protective ventilation was defined as follows: tidal volume ≤8 mL/kg of predicted body weight, positive end-expiratory pressure (PEEP) ≥5 cm H(2)O, and peak or plateau pressure ≤30 cm H(2)O. The development of ARDS was ascertained retrospectively by PaO(2)/FiO(2) ≤300 with new bilateral lung opacities on chest X-ray within one day of hypoxemia. We identified 62 patients who underwent early mechanical ventilation following SAH. PS and Continuous Positive Airway Pressure were common ventilator modes with a median tidal volume of 7.8 mL/kg [interquartile range 6.8-8.8], median peak pressure of 14 cm H(2)O [IQR 12-17], and median PEEP of 5 cm H(2)O [IQR 5-6]. Adherence to tidal volumes ≤8 mL/kg was seen in 64 % of all observations and peak pressures protective criteria were seen in 58 % of all observations. Thirty-one patients (50 %) were determined to have ARDS. ARDS patients were more frequently ventilated with a peak pressure >30 cm H(2)O (11.3 % of ARDS ventilation days vs. 0 % of non-ARDS ventilation days; p mechanical ventilation frequently breathe spontaneously, generating tidal volumes above usual protective thresholds regardless of meeting ARDS criteria. In patients with SAH, the presence of an additional ARDS risk factor should prompt close screening for the development of ARDS and

  7. Levitation properties of superconducting magnetic bearings using superconducting coils and bulk superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Yuuki; Seino, Hiroshi; Nagashima, Ken [Railway Technical Research Institute, 2-8-38 Hikari-cho, Kokubunji-shi, Tokyo 185-8540 (Japan)

    2010-11-15

    We have been developing a flywheel energy storage system (FESS) with 36 MJ energy capacity for a railway system with superconducting magnetic bearings (SMBs). We prepared two kinds of models using superconducting coils and bulk superconductors (SCs). One model demonstrated SMB load capacity of 20 kN and the other model proved non-contact stable levitation and non-contact rotation with SMBs. Combining these results, the feasibility of a 36 MJ energy capacity FESS with SMBs completely inside a cryostat has been confirmed. In this paper, we report the levitation properties of SMBs in these models.

  8. Levitation properties of superconducting magnetic bearings using superconducting coils and bulk superconductors

    International Nuclear Information System (INIS)

    Arai, Yuuki; Seino, Hiroshi; Nagashima, Ken

    2010-01-01

    We have been developing a flywheel energy storage system (FESS) with 36 MJ energy capacity for a railway system with superconducting magnetic bearings (SMBs). We prepared two kinds of models using superconducting coils and bulk superconductors (SCs). One model demonstrated SMB load capacity of 20 kN and the other model proved non-contact stable levitation and non-contact rotation with SMBs. Combining these results, the feasibility of a 36 MJ energy capacity FESS with SMBs completely inside a cryostat has been confirmed. In this paper, we report the levitation properties of SMBs in these models.

  9. Ventilator-driven xenon ventilation studies

    International Nuclear Information System (INIS)

    Chilcoat, R.T.; Thomas, F.D.; Gerson, J.I.

    1984-01-01

    A modification of a common commercial Xe-133 ventilation device is described for mechanically assisted ventilation imaging. The patient's standard ventilator serves as the power source controlling the ventilatory rate and volume during the xenon study, but the gases in the two systems are not intermixed. This avoids contamination of the ventilator with radioactive xenon. Supplemental oxygen and positive end-expiratory pressure (PEEP) are provided if needed. The system can be converted quickly for conventional studies with spontaneous respiration

  10. Intensive care unit ventilation for the non-intensivist

    African Journals Online (AJOL)

    Mode classification: volume versus pressure targeting. There is no evidence to ... and so most modern ventilators can be set up by the technician to directly display the .... mechanics: transpulmonary pressure and lung volume. Crit Care. 2013 ...

  11. Position paper -- Tank ventilation system design air flow rates

    International Nuclear Information System (INIS)

    Goolsby, G.K.

    1995-01-01

    The purpose of this paper is to document a project position on required ventilation system design air flow rates for the waste storage tanks currently being designed by project W-236A, the Multi-Function Waste Tank Facility (MWTF). The Title 1 design primary tank heat removal system consists of two systems: a primary tank vapor space ventilation system; and an annulus ventilation system. At the conclusion of Title 1 design, air flow rates for the primary and annulus ventilation systems were 960 scfm and 4,400 scfm, respectively, per tank. These design flow rates were capable of removing 1,250,000 Btu/hr from each tank. However, recently completed and ongoing studies have resulted in a design change to reduce the extreme case heat load to 700,000 Btu/hr. This revision of the extreme case heat load, coupled with results of scale model evaporative testing performed by WHC Thermal Hydraulics, allow for a reduction of the design air flow rates for both primary and annulus ventilation systems. Based on the preceding discussion, ICF Kaiser Hanford Co. concludes that the design should incorporate the following design air flow rates: Primary ventilation system--500 scfm maximum and Annulus ventilation system--1,100 scfm maximum. In addition, the minimum air flow rates in the primary and annulus ventilation systems will be investigated during Title 2 design. The results of the Title 2 investigation will determine the range of available temperature control using variable air flows to both ventilation systems

  12. Tracheostomy and invasive mechanical ventilation in amyotrophic lateral sclerosis: decision-making factors and survival analysis.

    Science.gov (United States)

    Kimura, Fumiharu

    2016-04-28

    Invasive and/or non-invasive mechanical ventilation are most important options of respiratory management in amyotrophic lateral sclerosis. We evaluated the frequency, clinical characteristics, decision-making factors about ventilation and survival analysis of 190 people with amyotrophic lateral sclerosis patients from 1990 until 2013. Thirty-one percentage of patients underwent tracheostomy invasive ventilation with the rate increasing more than the past 20 years. The ratio of tracheostomy invasive ventilation in patients >65 years old was significantly increased after 2000 (25%) as compared to before (10%). After 2010, the standard use of non-invasive ventilation showed a tendency to reduce the frequency of tracheostomy invasive ventilation. Mechanical ventilation prolonged median survival (75 months in tracheostomy invasive ventilation, 43 months in non-invasive ventilation vs natural course, 32 months). The life-extending effects by tracheostomy invasive ventilation were longer in younger patients ≤65 years old at the time of ventilation support than in older patients. Presence of partners and care at home were associated with better survival. Following factors related to the decision to perform tracheostomy invasive ventilation: patients ≤65 years old: greater use of non-invasive ventilation: presence of a spouse: faster tracheostomy: higher progression rate; and preserved motor functions. No patients who underwent tracheostomy invasive ventilation died from a decision to withdraw mechanical ventilation. The present study provides factors related to decision-making process and survival after tracheostomy and help clinicians and family members to expand the knowledge about ventilation.

  13. Mesoporous nanocrystalline film architecture for capacitive storage devices

    Science.gov (United States)

    Dunn, Bruce S.; Tolbert, Sarah H.; Wang, John; Brezesinski, Torsten; Gruner, George

    2017-05-16

    A mesoporous, nanocrystalline, metal oxide construct particularly suited for capacitive energy storage that has an architecture with short diffusion path lengths and large surface areas and a method for production are provided. Energy density is substantially increased without compromising the capacitive charge storage kinetics and electrode demonstrates long term cycling stability. Charge storage devices with electrodes using the construct can use three different charge storage mechanisms immersed in an electrolyte: (1) cations can be stored in a thin double layer at the electrode/electrolyte interface (non-faradaic mechanism); (2) cations can interact with the bulk of an electroactive material which then undergoes a redox reaction or phase change, as in conventional batteries (faradaic mechanism); or (3) cations can electrochemically adsorb onto the surface of a material through charge transfer processes (faradaic mechanism).

  14. Demand Controlled Ventilation and Classroom Ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Davies, Molly [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Eliseeva, Ekaterina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Faulkner, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hong, Tienzen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sullivan, Douglas P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-05-01

    This document summarizes a research effort on demand controlled ventilation and classroom ventilation. The research on demand controlled ventilation included field studies and building energy modeling.

  15. Demand controlled ventilation and classroom ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Davies, Molly [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Eliseeva, Ekaterina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Faulkner, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hong, Tienzen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sullivan, Douglas P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-01-06

    This document summarizes a research effort on demand controlled ventilation and classroom ventilation. The research on demand controlled ventilation included field studies and building energy modeling.

  16. Dismantlement and removal of Old Hydrofracture Facility bulk storage bins and water tank, Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1998-03-01

    The Old Hydrofracture Facility (OHF), located at Oak Ridge National Laboratory (ORNL), was constructed in 1963 to allow experimentation and operations with an integrated solid storage, mixing, and grout injection facility. During its operation, OHF blended liquid low-level waste with grout and used a hydrofracture process to pump the waste into a deep low-permeable shale formation. Since the OHF Facility was taken out of service in 1980, the four bulk storage bins located adjacent to Building 7852 had deteriorated to the point that they were a serious safety hazard. The ORNL Surveillance and Maintenance Program requested and received permission from the US Department of Energy to dismantle the bins as a maintenance action and send the free-released metal to an approved scrap metal vendor. A 25,000-gal stainless steel water tank located at the OHF site was included in the scope. A fixed-price subcontract was signed with Allied Technology Group, Inc., to remove the four bulk storage bins and water tank to a staging area where certified Health Physics personnel could survey, segregate, package, and send the radiologically clean scrap metal to an approved scrap metal vendor. All radiologically contaminated metal and metal that could not be surveyed was packaged and staged for later disposal. Permissible personnel exposure limits were not exceeded, no injuries were incurred, and no health and safety violations occurred throughout the duration of the project. Upon completion of the dismantlement, the project had generated 53,660 lb of clean scrap metal (see Appendix D). This resulted in $3,410 of revenue generated and a cost avoidance of an estimated $100,000 in waste disposal fees

  17. Randomized cross-over trial of ventilator modes during non-invasive ventilation titration in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Vrijsen, Bart; Buyse, Bertien; Belge, Catharina; Vanpee, Goele; Van Damme, Philip; Testelmans, Dries

    2017-08-01

    Non-invasive ventilation (NIV) improves survival, quality of life and sleep in patients with amyotrophic lateral sclerosis (ALS). Nevertheless, NIV titration is conducted in different ways. We aim to provide more insight into NIV titration by comparing the effects of a spontaneous (S) and spontaneous-timed (ST) modes on gas exchange, sleep architecture and patient-ventilator asynchronies (PVAs). After an initial night of NIV titration, patients were randomized to S or ST mode in a cross-over design. NIV was titrated using polysomnography, oximetry (oxygen saturation, SpO 2 %) and transcutaneous carbon dioxide (PtcCO 2 ) measurement. PVAs were analysed breath-by-breath. Thirteen patients were analysed after inclusion. ST mode showed better results in gas exchange (minimal SpO 2 %: 83 (80-89)% vs 87 (84-89)%; oxygen desaturation index: 15 (5-28)/h sleep vs 7 (3-9)/h sleep; PtcCO 2 >55 mm Hg: 20 (0-59)% vs 0 (0-27)% total sleep time for S and ST mode, respectively, all P < 0.05) and respiratory events (obstructive: 8.9 (1.2-18.3)/h sleep vs 1.8 (0.3-4.9)/h sleep and central: 2.6 (0.4-14.1)/h sleep vs 0.2 (0.0-1.1)/h sleep for S and ST mode, respectively, both P < 0.01). No differences in sleep architecture were found. Ineffective efforts and respiratory events were more frequently present in S mode. Nevertheless, four patients were discharged on S mode as these patients showed clinically better results for sleep architecture and PVA during the night on S mode. ST mode shows better results in gas exchange, respiratory events and PVA. Nevertheless, accurate NIV titration remains necessary as some patients show equal or better results when using the S mode. © 2017 Asian Pacific Society of Respirology.

  18. Reduced survival in patients with ALS with upper airway obstructive events on non-invasive ventilation.

    Science.gov (United States)

    Georges, Marjolaine; Attali, Valérie; Golmard, Jean Louis; Morélot-Panzini, Capucine; Crevier-Buchman, Lise; Collet, Jean-Marc; Tintignac, Anne; Morawiec, Elise; Trosini-Desert, Valery; Salachas, François; Similowski, Thomas; Gonzalez-Bermejo, Jesus

    2016-10-01

    Non-invasive ventilation (NIV) is part of standard care in amyotrophic lateral sclerosis (ALS). Intolerance or unavailability of NIV, as well as the quality of correction of nocturnal hypoventilation, has a direct impact on prognosis. We describe the importance of NIV failure due to upper airway obstructive events, the clinical characteristics, as well as their impact on the prognosis of ALS. Retrospective analysis of the data of 190 patients with ALS and NIV in a single centre for the period 2011-2014. 179 patients tolerating NIV for more than 4 h per night without leaks were analysed. Among the 179 patients, after correction of leaks, 73 remained inadequately ventilated at night (defined as more than 5% of the night spent at NIV, no difference was demonstrated between patients with and without upper airway obstructive events. In all patients, upper airway obstruction was concomitant with reduction of ventilatory drive. This study shows that upper airway obstruction during NIV occurs in patients with ALS and is associated with poorer prognosis. Such events should be identified as they can be corrected by adjusting ventilator settings. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  19. Non-invasive ventilation: comparison of effectiveness, safety, and management in acute heart failure syndromes and acute exacerbations of chronic obstructive pulmonary disease.

    Science.gov (United States)

    Pladeck, T; Hader, C; Von Orde, A; Rasche, K; Wiechmann, H W

    2007-11-01

    Continuous positive airway pressure ventilation (CPAP) and non-invasive positive pressure ventilation (NPPV) are accepted treatments in acute cardiogenic pulmonary edema (ACPE) and acute exacerbation of chronic obstructive pulmonary disease (AECOPD). The aim of the study was a comparison of effectiveness, safety, and management of NPPV in ACPE and AECOPD trying to find an approach for standard management in intensive care. Thirty patients with acute respiratory failure (14 due to ACPE, 16 due to AECOPD) were prospectively included into the study. If clinical stability could not be achieved by standard therapy (pharmacological therapy and oxygen) patients were treated by non-invasive ventilation (NPPV) using a BiPAP-Vision device in S/T-mode. During the first 90 min after the onset of NPPV respiratory and vital parameters were documented every 30 min. Additional relevant outcome parameters (need for intubation, duration of ICU stay, complications and mortality) were monitored. We found that 85.7% of the ACPE patients and 50.0% of the AECOPD patients were treated successfully with NPPV. Intubation rate was 31.2% in the AECOPD group and 14.3% in the ACPE group. 78.6% of the ACPE patients and 43.8% of the AECOPD patients were regularly discharged from hospital in a good condition. In the first 90 min of NIV, there was a significant amelioration of respiratory and other vital parameters. In ACPE patients there was a significant increase in PaO2 from 58.9 mmHg to 80.6 mmHg and of oxygen saturation (SaO2) from 85.1% to 93.1% without changing the inspiratory O2 concentration. This effect was comparable in the AECOPD group, but only could be achieved by increasing the inspiratory ventilation pressure. In the ACPE group inspiratory ventilation pressure could be reduced. In conclusion, in acute respiratory failure, ACPE patients comparably profit from NPPV as do patients with AECOPD, but the algorithm of titration for non-invasive ventilation pressure is different.

  20. Techno-economic assessment of the need for bulk energy storage in low-carbon electricity systems with a focus on compressed air storage (CAES)

    Science.gov (United States)

    Safaei Mohamadabadi, Hossein

    Increasing electrification of the economy while decarbonizing the electricity supply is among the most effective strategies for cutting greenhouse gas (GHG) emissions in order to abate climate change. This thesis offers insights into the role of bulk energy storage (BES) systems to cut GHG emissions from the electricity sector. Wind and solar energies can supply large volumes of low-carbon electricity. Nevertheless, large penetration of these resources poses serious reliability concerns to the grid, mainly because of their intermittency. This thesis evaluates the performance of BES systems - especially compressed air energy storage (CAES) technology - for integration of wind energy from engineering and economic aspects. Analytical thermodynamic analysis of Distributed CAES (D-CAES) and Adiabatic CAES (A-CAES) suggest high roundtrip storage efficiencies ( 80% and 70%) compared to conventional CAES ( 50%). Using hydrogen to fuel CAES plants - instead of natural gas - yields a low overall efficiency ( 35%), despite its negligible GHG emissions. The techno-economic study of D-CAES shows that exporting compression heat to low-temperature loads (e.g. space heating) can enhance both the economic and emissions performance of compressed air storage plants. A case study for Alberta, Canada reveals that the abatement cost of replacing a conventional CAES with D-CAES plant practicing electricity arbitrage can be negative (-$40 per tCO2e, when the heat load is 50 km away from the air storage site). A green-field simulation finds that reducing the capital cost of BES - even drastically below current levels - does not substantially impact the cost of low-carbon electricity. At a 70% reduction in the GHG emissions intensity of the grid, gas turbines remain three times more cost-efficient in managing the wind variability compared to BES (in the best case and with a 15-minute resolution). Wind and solar thus, do not need to wait for availability of cheap BES systems to cost

  1. Anaesthesia ventilators

    Directory of Open Access Journals (Sweden)

    Rajnish K Jain

    2013-01-01

    Full Text Available Anaesthesia ventilators are an integral part of all modern anaesthesia workstations. Automatic ventilators in the operating rooms, which were very simple with few modes of ventilation when introduced, have become very sophisticated with many advanced ventilation modes. Several systems of classification of anaesthesia ventilators exist based upon various parameters. Modern anaesthesia ventilators have either a double circuit, bellow design or a single circuit piston configuration. In the bellows ventilators, ascending bellows design is safer than descending bellows. Piston ventilators have the advantage of delivering accurate tidal volume. They work with electricity as their driving force and do not require a driving gas. To enable improved patient safety, several modifications were done in circle system with the different types of anaesthesia ventilators. Fresh gas decoupling is a modification done in piston ventilators and in descending bellows ventilator to reduce th incidence of ventilator induced volutrauma. In addition to the conventional volume control mode, modern anaesthesia ventilators also provide newer modes of ventilation such as synchronised intermittent mandatory ventilation, pressure-control ventilation and pressure-support ventilation (PSV. PSV mode is particularly useful for patients maintained on spontaneous respiration with laryngeal mask airway. Along with the innumerable benefits provided by these machines, there are various inherent hazards associated with the use of the ventilators in the operating room. To use these workstations safely, it is important for every Anaesthesiologist to have a basic understanding of the mechanics of these ventilators and breathing circuits.

  2. Anaesthesia ventilators.

    Science.gov (United States)

    Jain, Rajnish K; Swaminathan, Srinivasan

    2013-09-01

    Anaesthesia ventilators are an integral part of all modern anaesthesia workstations. Automatic ventilators in the operating rooms, which were very simple with few modes of ventilation when introduced, have become very sophisticated with many advanced ventilation modes. Several systems of classification of anaesthesia ventilators exist based upon various parameters. Modern anaesthesia ventilators have either a double circuit, bellow design or a single circuit piston configuration. In the bellows ventilators, ascending bellows design is safer than descending bellows. Piston ventilators have the advantage of delivering accurate tidal volume. They work with electricity as their driving force and do not require a driving gas. To enable improved patient safety, several modifications were done in circle system with the different types of anaesthesia ventilators. Fresh gas decoupling is a modification done in piston ventilators and in descending bellows ventilator to reduce th incidence of ventilator induced volutrauma. In addition to the conventional volume control mode, modern anaesthesia ventilators also provide newer modes of ventilation such as synchronised intermittent mandatory ventilation, pressure-control ventilation and pressure-support ventilation (PSV). PSV mode is particularly useful for patients maintained on spontaneous respiration with laryngeal mask airway. Along with the innumerable benefits provided by these machines, there are various inherent hazards associated with the use of the ventilators in the operating room. To use these workstations safely, it is important for every Anaesthesiologist to have a basic understanding of the mechanics of these ventilators and breathing circuits.

  3. Anaesthesia ventilators

    Science.gov (United States)

    Jain, Rajnish K; Swaminathan, Srinivasan

    2013-01-01

    Anaesthesia ventilators are an integral part of all modern anaesthesia workstations. Automatic ventilators in the operating rooms, which were very simple with few modes of ventilation when introduced, have become very sophisticated with many advanced ventilation modes. Several systems of classification of anaesthesia ventilators exist based upon various parameters. Modern anaesthesia ventilators have either a double circuit, bellow design or a single circuit piston configuration. In the bellows ventilators, ascending bellows design is safer than descending bellows. Piston ventilators have the advantage of delivering accurate tidal volume. They work with electricity as their driving force and do not require a driving gas. To enable improved patient safety, several modifications were done in circle system with the different types of anaesthesia ventilators. Fresh gas decoupling is a modification done in piston ventilators and in descending bellows ventilator to reduce th incidence of ventilator induced volutrauma. In addition to the conventional volume control mode, modern anaesthesia ventilators also provide newer modes of ventilation such as synchronised intermittent mandatory ventilation, pressure-control ventilation and pressure-support ventilation (PSV). PSV mode is particularly useful for patients maintained on spontaneous respiration with laryngeal mask airway. Along with the innumerable benefits provided by these machines, there are various inherent hazards associated with the use of the ventilators in the operating room. To use these workstations safely, it is important for every Anaesthesiologist to have a basic understanding of the mechanics of these ventilators and breathing circuits. PMID:24249886

  4. Use of noninvasive and invasive mechanical ventilation in cardiogenic shock

    DEFF Research Database (Denmark)

    Hongisto, Mari; Lassus, Johan; Tarvasmaki, Tuukka

    2017-01-01

    BACKGROUND: Despite scarce data, invasive mechanical ventilation (MV) is widely recommended over non-invasive ventilation (NIV) for ventilatory support in cardiogenic shock (CS). We assessed the real-life use of different ventilation strategies in CS and their influence on outcome focusing on the...

  5. Comparison of endotracheal aspirate and non-bronchoscopic bronchoalveolar lavage in the diagnosis of ventilator-associated pneumonia in a pediatric intensive care unit.

    Science.gov (United States)

    Yıldız-Atıkan, Başak; Karapınar, Bülent; Aydemir, Şöhret; Vardar, Fadıl

    2015-01-01

    Ventilator-associated pneumonia (VAP) is defined as pneumonia occuring in any period of mechanical ventilation. There is no optimal diagnostic method in current use and in this study we aimed to compare two non-invasive diagnostic methods used in diagnosis of VAP in children. This prospective study was conducted in 8 bedded Pediatric Intensive Care Unit at Ege University Children´s Hospital. Endotracheal aspiration (ETA) and non-bronchoscopic bronchoalveolar lavage (BAL) were performed in case of developing VIP after 48 hours of ventilation. Quantitative cultures were examined in Ege University Department of Diagnostic Microbiology, Bacteriology Laboratory. Fourty-one patients were enrolled in the study. The mean age of study subjects was 47.2±53.6 months. A total of 28 in 82 specimens taken with both methods were negative/negative; 28 had positive result with ETA and a negative result with non-bronchoscopic BAL and both results were negative in 26 specimens. There were no patients whose respiratory specimen culture was negative with ETA and positive with non-bronchoscopic BAL. These results imply that there is a significant difference between two diagnostic methods (p VAP; therefore, ETA results were compared with this method. ETA's sensitivity, specificity, negative and positive predictive values were 100%, 50%, 100% and 48% respectively. The study revealed the ease of usability and the sensitivity of non-bronchoscopic BAL, in comparison with ETA.

  6. Evaluation of ventilators for mouthpiece ventilation in neuromuscular disease.

    Science.gov (United States)

    Khirani, Sonia; Ramirez, Adriana; Delord, Vincent; Leroux, Karl; Lofaso, Frédéric; Hautot, Solène; Toussaint, Michel; Orlikowski, David; Louis, Bruno; Fauroux, Brigitte

    2014-09-01

    Daytime mouthpiece ventilation is a useful adjunct to nocturnal noninvasive ventilation (NIV) in patients with neuromuscular disease. The aims of the study were to analyze the practice of mouthpiece ventilation and to evaluate the performance of ventilators for mouthpiece ventilation. Practice of mouthpiece ventilation was assessed by a questionnaire, and the performance of 6 home ventilators with mouthpiece ventilation was assessed in a bench test using 24 different conditions per ventilator: 3 mouthpieces, a child and an adult patient profile, and 4 ventilatory modes. Questionnaires were obtained from 30 subjects (mean age 33 ± 11 y) using NIV for 12 ± 7 y. Fifteen subjects used NIV for > 20 h/day, and 11 were totally ventilator-dependent. The subject-reported benefits of mouthpiece ventilation were a reduction in dyspnea (73%) and fatigue (93%) and an improvement in speech (43%) and eating (27%). The bench study showed that none of the ventilators, even those with mouthpiece ventilation software, were able to deliver mouthpiece ventilation without alarms and/or autotriggering in each condition. Alarms and/or ineffective triggering or autotriggering were observed in 135 of the 198 conditions. The occurrence of alarms was more common with a large mouthpiece without a filter compared to a small mouthpiece with a filter (P ventilator. Subjects are satisfied with mouthpiece ventilation. Alarms are common with home ventilators, although less common in those with mouthpiece ventilation software. Improvements in home ventilators are needed to facilitate the expansion of mouthpiece ventilation. Copyright © 2014 by Daedalus Enterprises.

  7. Storage tests with irradiated and non-irradiated onions

    International Nuclear Information System (INIS)

    Gruenewald, T.; Rumpf, G.; Troemel, I.; Bundesforschungsanstalt fuer Ernaehrung, Karlsruhe

    1978-07-01

    The results of several test series on the storage of irradiated and non-irradiated German grown onion are reported. Investigated was the influence of the irradiation conditions such as time and dose and of the storage conditions on sprouting, spoilage, browning of the vegetation centres, composition of the onions, strength and sensorial properties of seven different onion varieties. If the onions were irradiated during the dormancy period following harvest, a dose of 50 Gy (krad) was sufficient to prevent sprouting. Regarding the irradiated onions, it was not possible by variation of the storage conditions within the limits set by practical requirements to extend the dormancy period or to prevent browning of the vegetation centres, however. (orig.) 891 MG 892 RSW [de

  8. Non-Invasive Ventilation in Patients with Heart Failure: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Hugo Souza Bittencourt

    Full Text Available Abstract Non-invasive ventilation (NIV may perfect respiratory and cardiac performance in patients with heart failure (HF. The objective of the study to establish, through systematic review and meta-analysis, NIV influence on functional capacity of HF patients. A systematic review with meta-analysis of randomized studies was carried out through research of databases of Cochrane Library, SciELO, Pubmed and PEDro, using the key-words: heart failure, non-invasive ventilation, exercise tolerance; and the free terms: bi-level positive airway pressure (BIPAP, continuous positive airway pressure (CPAP, and functional capacity (terms were searched for in English and Portuguese using the Boolean operators AND and OR. Methodological quality was ensured through PEDro scale. Weighted averages and a 95% confidence interval (CI were calculated. The meta-analysis was done thorugh the software Review Manager, version 5.3 (Cochrane Collaboration. Four randomized clinical trials were included. Individual studies suggest NIV improved functional capacity. NIV resulted in improvement in the distance of the six-minute walk test (6MWT (68.7m 95%CI: 52.6 to 84.9 in comparison to the control group. We conclude that the NIV is an intervention that promotes important effects in the improvement of functional capacity of HF patients. However, there is a gap in literature on which are the most adequate parameters for the application of this technique.

  9. ANALISIS KESELAMATAN TERMOHIDROLIK BULK SHIELDING REAKTOR KARTINI

    Directory of Open Access Journals (Sweden)

    Azizul Khakim

    2015-10-01

    Full Text Available ABSTRAK ANALISIS KESELAMATAN TERMOHIDROLIK BULK SHIELDING REAKTOR KARTINI. Bulk shielding merupakan fasilitas yang terintegrasi dengan reaktor Kartini yang berfungsi sebagai penyimpanan sementara bahan bakar bekas. Fasilitas ini merupakan fasilitas yang termasuk dalam struktur, sistem dan komponen (SSK yang penting bagi keselamatan. Salah satu fungsi keselamatan dari sistem penanganan dan penyimpanan bahan bakar adalah mencegah kecelakaan kekritisan yang tak terkendali dan membatasi naiknya temperatur bahan bakar. Analisis keselamatan paling kurang harus mencakup analisis keselamatan dari sisi neutronik dan termo hidrolik Bulk shielding. Analisis termo hidrolik ditujukan untuk memastikan perpindahan panas dan proses pendinginan bahan bakar bekas berjalan baik dan tidak terjadi akumulasi panas yang mengancam integritas bahan bakar. Code tervalidasi PARET/ANL digunakan untuk analisis pendinginan dengan mode konveksi alam. Hasil perhitungan menunjukkan bahwa mode pendinginan konvekasi alam cukup memadai dalam mendinginkan panas sisa tanpa mengakibatkan kenaikan temperatur bahan bakar yang signifikan. Kata kunci: Bulk shielding, bahan bakar bekas, konveksi alam, PARET.   ABSTRACT THERMAL HYDRAULIC SAFETY ANALYSIS OF BULK SHIELDING KARTINI REACTOR. Bulk shielding is an integrated facility to Kartini reactor which is used for temporary spent fuels storage. The facility is one of the structures, systems and components (SSCs important to safety. Among the safety functions of fuel handling and storage are to prevent any uncontrolable criticality accidents and to limit the fuel temperature increase. Safety analyses should, at least, cover neutronic and thermal hydraulic calculations of the bulk shielding. Thermal hydraulic analyses were intended to ensure that heat removal and the process of the spent fuels cooling takes place adequately and no heat accumulation that challenges the fuel integrity. Validated code, PARET/ANL was used for analysing the

  10. 12th US/North American mine ventilation symposium

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, K.G. (ed.)

    2008-07-01

    Topics covered include: ventilation planning for metal/non-metal and coal mines, spontaneous combustion, heat and humidity, miner's act and mine seals, numerical modeling, coal mine methane, mine dust, tunnel ventilation, mine fans, diesel emissions control, mine fires, and general ventilation design and monitoring. The papers, talks and presentations are available for free download from the www.smenet.org site; printed copies of the proceedings are no longer available.

  11. Direct non-destructive observation of bulk nucleation in 30% deformed aluminum

    DEFF Research Database (Denmark)

    West, Stine; Schmidt, Søren; Sørensen, Henning Osholm

    2009-01-01

    A 30% deformed aluminum sample was mapped non-destructively using three-dimensional X-ray diffraction (3DXRD) before and after annealing to nucleation of recrystallization. Nuclei appeared in the bulk of the sample. Their positions and volumes were determined, and the crystallographic orientations...... were compared with the orientations of the deformed grains. It was found that nuclei with new orientations can form and their orientations have been related to the dislocation structure in the deformed grains....

  12. Stockpiling Ventilators for Influenza Pandemics.

    Science.gov (United States)

    Huang, Hsin-Chan; Araz, Ozgur M; Morton, David P; Johnson, Gregory P; Damien, Paul; Clements, Bruce; Meyers, Lauren Ancel

    2017-06-01

    In preparing for influenza pandemics, public health agencies stockpile critical medical resources. Determining appropriate quantities and locations for such resources can be challenging, given the considerable uncertainty in the timing and severity of future pandemics. We introduce a method for optimizing stockpiles of mechanical ventilators, which are critical for treating hospitalized influenza patients in respiratory failure. As a case study, we consider the US state of Texas during mild, moderate, and severe pandemics. Optimal allocations prioritize local over central storage, even though the latter can be deployed adaptively, on the basis of real-time needs. This prioritization stems from high geographic correlations and the slightly lower treatment success assumed for centrally stockpiled ventilators. We developed our model and analysis in collaboration with academic researchers and a state public health agency and incorporated it into a Web-based decision-support tool for pandemic preparedness and response.

  13. Total and non-seasalt sulfate and chloride measured in bulk precipitation samples from the Kilauea Volcano area, Hawaii

    Science.gov (United States)

    Scholl, M.A.; Ingebritsen, S.E.

    1995-01-01

    Six-month cumulative precipitation samples provide estimates of bulk deposition of sulfate and chloride for the southeast part of the Island of Hawaii during four time periods: August 1991 to February 1992, February 1992 to September 1992, March 1993 to September 1993, and September 1993 to February 1994. Total estimated bulk deposition rates for sulfate ranged from 0.12 to 24 grams per square meter per 180 days, and non-seasalt sulfate deposition ranged from 0.06 to 24 grams per square meter per 180 days. Patterns of non-seasalt sulfate deposition were generally related to prevailing wind directions and the proximity of the collection site to large sources of sulfur gases, namely Kilauea Volcano's summit and East Rift Zone eruption. Total chloride deposition from bulk precipitation samples ranged from 0.01 to 17 grams per square meter per 180 days. Chloride appeared to be predominantly from oceanic sources, as non- seasalt chloride deposition was near zero for most sites.

  14. Spent nuclear fuel storage device and spent nuclear fuel storage method using the device

    International Nuclear Information System (INIS)

    Tani, Yutaro

    1998-01-01

    Storage cells attachably/detachably support nuclear fuel containing vessels while keeping the vertical posture of them. A ventilation pipe which forms air channels for ventilating air to the outer circumference of the nuclear fuel containing vessel is disposed at the outer circumference of the nuclear fuel containing vessel contained in the storage cell. A shielding port for keeping the support openings gas tightly is moved, and a communication port thereof can be aligned with the upper portion of the support opening. The lower end of the transporting and containing vessel is placed on the shielding port, and an opening/closing shutter is opened. The gas tightness is kept by the shielding port, the nuclear fuel containing vessel filled with spent nuclear fuels is inserted to the support opening and supported. Then, the support opening is closed by a sealing lid. (I.N.)

  15. Noninvasive ventilation in hypoxemic respiratory failure

    Directory of Open Access Journals (Sweden)

    Raja Dhar

    2016-01-01

    Full Text Available Noninvasive ventilation (NIV refers to positive pressure ventilation delivered through a noninvasive interface (nasal mask, facemask, or nasal plugs etc. Over the past decade its use has become more common as its benefits are increasingly recognized. This review will focus on the evidence supporting the use of NIV in various conditions resulting in acute hypoxemic respiratory failure (AHRF, that is, non-hypercapnic patients having acute respiratory failure in the absence of a cardiac origin or underlying chronic pulmonary disease. Outcomes depend on the patient's diagnosis and clinical characteristics. Patients should be monitored closely for signs of noninvasive ventilation failure and promptly intubated before a crisis develops. The application of noninvasive ventilation by a trained and experienced team, with careful patient selection, should optimize patient outcomes.

  16. Entropy, pricing and productivity of pumped-storage

    Science.gov (United States)

    Karakatsanis, Georgios; Tyralis, Hristos; Tzouka, Katerina

    2016-04-01

    Pumped-storage constitutes today a mature method of bulk electricity storage in the form of hydropower. This bulk electricity storability upgrades the economic value of hydropower as it may mitigate -or even neutralize- stochastic effects deriving from various geophysical and socioeconomic factors, which produce numerous load balance inefficiencies due to increased uncertainty. Pumped-storage further holds a key role for unifying intermittent renewable (i.e. wind, solar) units with controllable non-renewable (i.e. nuclear, coal) fuel electricity generation plants into integrated energy systems. We develop a set of indicators for the measurement of performance of pumped-storage, in terms of the latter's energy and financial contribution to the energy system. More specifically, we use the concept of entropy in order to examine: (1) the statistical features -and correlations- of the energy system's intermittent components and (2) the statistical features of electricity demand prediction deviations. In this way, the macroeconomics of pumped-storage emerges naturally from its statistical features (Karakatsanis et al. 2014). In addition, these findings are combined to actual daily loads. Hence, not only the amount of energy harvested from the pumped-storage component is expected to be important, but the harvesting time as well, as the intraday price of electricity varies significantly. Additionally, the structure of the pumped-storage market proves to be a significant factor as well for the system's energy and financial performance (Paine et al. 2014). According to the above, we aim at postulating a set of general rules on the productivity of pumped-storage for (integrated) energy systems. Keywords: pumped-storage, storability, economic value of hydropower, stochastic effects, uncertainty, energy systems, entropy, intraday electricity price, productivity References 1. Karakatsanis, Georgios et al. (2014), Entropy, pricing and macroeconomics of pumped-storage systems

  17. Bulk characterization methods for non-centrosymmetric materials: second-harmonic generation, piezoelectricity, pyroelectricity, and ferroelectricity.

    Science.gov (United States)

    Ok, Kang Min; Chi, Eun Ok; Halasyamani, P Shiv

    2006-08-01

    Characterization methods for bulk non-centrosymmetric compounds are described. These methods include second-harmonic generation, piezoelectricity, pyroelectricity, and ferroelectricity. In this tutorial review with each phenomenon, details are given of the measurement techniques along with a brief history and background. Finally, data interpretation is discussed.

  18. Summary of human responses to ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Seppanen, Olli A.; Fisk, William J.

    2004-06-01

    The effects of ventilation on indoor air quality and health is a complex issue. It is known that ventilation is necessary to remove indoor generated pollutants from indoor air or dilute their concentration to acceptable levels. But, as the limit values of all pollutants are not known, the exact determination of required ventilation rates based on pollutant concentrations and associated risks is seldom possible. The selection of ventilation rates has to be based also on epidemiological research (e.g. Seppanen et al., 1999), laboratory and field experiments (e.g. CEN 1996, Wargocki et al., 2002a) and experience (e.g. ECA 2003). Ventilation may also have harmful effects on indoor air quality and climate if not properly designed, installed, maintained and operated as summarized by Seppdnen (2003). Ventilation may bring indoors harmful substances that deteriorate the indoor environment. Ventilation also affects air and moisture flow through the building envelope and may lead to moisture problems that deteriorate the structures of the building. Ventilation changes the pressure differences over the structures of building and may cause or prevent the infiltration of pollutants from structures or adjacent spaces. Ventilation is also in many cases used to control the thermal environment or humidity in buildings. Ventilation can be implemented with various methods which may also affect health (e.g. Seppdnen and Fisk, 2002, Wargocki et al., 2002a). In non residential buildings and hot climates, ventilation is often integrated with air-conditioning which makes the operation of ventilation system more complex. As ventilation is used for many purposes its health effects are also various and complex. This paper summarizes the current knowledge on positive and negative effects of ventilation on health and other human responses. The focus of the paper is on office-type working environment and residential buildings. In the industrial premises the problems of air quality are usually

  19. Radiolysis and temperature effects in case of undeground storage of bitumen

    International Nuclear Information System (INIS)

    Smailos, E.; Diefenbacher, W.; Korthaus, E.; Comper, W.

    1976-01-01

    On conservative assumptions limit values were determined for the specific activity in the bitumen products, which safely avoid under the conditions of storage in a non-ventilated prototype cavity both the formation of an ignitable radiolytic gas/air mixture and intolerable heating of wastes products over the entire storage time. Depending on the filling factor of the cavity and on the age of fixed fission products, the limit values of the specific activity in the waste products allowing to avoid an ignitable gas/air mixture in the cavity range from 0.09 Ci/l to 0.78 Ci/l. The respective limit values of specific activity allowing to avoid intolerable heating of wastes (> 70 0 C) range from 0.3 Ci/l to 0.7 Ci/l, depending on the age of fission products and on the type of storage

  20. Mechanical ventilation in abdominal surgery.

    Science.gov (United States)

    Futier, E; Godet, T; Millot, A; Constantin, J-M; Jaber, S

    2014-01-01

    One of the key challenges in perioperative care is to reduce postoperative morbidity and mortality. Patients who develop postoperative morbidity but survive to leave hospital have often reduced functional independence and long-term survival. Mechanical ventilation provides a specific example that may help us to shift thinking from treatment to prevention of postoperative complications. Mechanical ventilation in patients undergoing surgery has long been considered only as a modality to ensure gas exchange while allowing maintenance of anesthesia with delivery of inhaled anesthetics. Evidence is accumulating, however, suggesting an association between intraoperative mechanical ventilation strategy and postoperative pulmonary function and clinical outcome in patients undergoing abdominal surgery. Non-protective ventilator settings, especially high tidal volume (VT) (>10-12mL/kg) and the use of very low level of positive end-expiratory pressure (PEEP) (PEEPventilator-associated lung injury in patients with healthy lungs. Stimulated by previous findings in patients with acute respiratory distress syndrome, the use of lower tidal volume ventilation is becoming increasingly more common in the operating room. However, lowering tidal volume, though important, is only part of the overall multifaceted approach of lung protective mechanical ventilation. In this review, we aimed at providing the most recent and relevant clinical evidence regarding the use of mechanical ventilation in patients undergoing abdominal surgery. Copyright © 2014 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier SAS. All rights reserved.

  1. Bench performance of ventilators during simulated paediatric ventilation.

    Science.gov (United States)

    Park, M A J; Freebairn, R C; Gomersall, C D

    2013-05-01

    This study compares the accuracy and capabilities of various ventilators using a paediatric acute respiratory distress syndrome lung model. Various compliance settings and respiratory rate settings were used. The study was done in three parts: tidal volume and FiO2 accuracy; pressure control accuracy and positive end-expiratory pressure (PEEP) accuracy. The parameters set on the ventilator were compared with either or both of the measured parameters by the test lung and the ventilator. The results revealed that none of the ventilators could consistently deliver tidal volumes within 1 ml/kg of the set tidal volume, and the discrepancy between the delivered volume and the volume measured by the ventilator varied greatly. The target tidal volume was 8 ml/kg, but delivered tidal volumes ranged from 3.6-11.4 ml/kg and the volumes measured by the ventilator ranged from 4.1-20.6 ml/kg. All the ventilators maintained pressure within 20% of the set pressure, except one ventilator which delivered pressures of up to 27% higher than the set pressure. Two ventilators maintained PEEP within 10% of the prescribed PEEP. The majority of the readings were also within 10%. However, three ventilators delivered, at times, PEEPs over 20% higher. In conclusion, as lung compliance decreases, especially in paediatric patients, some ventilators perform better than others. This study highlights situations where ventilators may not be able to deliver, nor adequately measure, set tidal volumes, pressure, PEEP or FiO2.

  2. Anaesthesia ventilators

    OpenAIRE

    Jain, Rajnish K; Swaminathan, Srinivasan

    2013-01-01

    Anaesthesia ventilators are an integral part of all modern anaesthesia workstations. Automatic ventilators in the operating rooms, which were very simple with few modes of ventilation when introduced, have become very sophisticated with many advanced ventilation modes. Several systems of classification of anaesthesia ventilators exist based upon various parameters. Modern anaesthesia ventilators have either a double circuit, bellow design or a single circuit piston configuration. In the bello...

  3. [Anesthesia ventilators].

    Science.gov (United States)

    Otteni, J C; Beydon, L; Cazalaà, J B; Feiss, P; Nivoche, Y

    1997-01-01

    To review anaesthesia ventilators in current use in France by categories of ventilators. References were obtained from computerized bibliographic search. (Medline), recent review articles, the library of the service and personal files. Anaesthesia ventilators can be allocated into three groups, depending on whether they readminister expired gases or not or allow both modalities. Contemporary ventilators provide either constant volume ventilation, or constant pressure ventilation, with or without a pressure plateau. Ventilators readministering expired gases after CO2 absorption, or closed circuit ventilators, are either of a double- or a single-circuit design. Double-circuit ventilators, or pneumatical bag or bellows squeezers, or bag-in-bottle or bellows-in-bottle (or box) ventilators, consist of a primary, or driving circuit (bottle or box) and a secondary or patient circuit (including a bag or a bellows or membrane chambers). Bellows-in-bottle ventilators have either standing bellows ascending at expiration, or hanging bellows, descending at expiration. Ascending bellows require a positive pressure of about 2 cmH2O throughout exhalation to allow the bellows to refill. The expired gas volume is a valuable indicator for leak and disconnection. Descending bellows generate a slight negative pressure during exhalation. In case of leak or disconnection they aspirate ambient air and cannot act therefore as an indicator for integrity of the circuit and the patient connection. Closed circuit ventilators with a single-circuit (patient circuit) include a insufflating device consisting either in a bellows or a cylinder with a piston, operated by a electric or pneumatic motor. As the hanging bellows of the double circuit ventilators, they generate a slight negative pressure during exhalation and aspirate ambient air in case of leak or disconnection. Ventilators not designed for the readministration of expired gases, or open circuit ventilators, are generally stand

  4. The predictive value of respiratory function tests for non-invasive ventilation in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Tilanus, T B M; Groothuis, J T; TenBroek-Pastoor, J M C; Feuth, T B; Heijdra, Y F; Slenders, J P L; Doorduin, J; Van Engelen, B G; Kampelmacher, M J; Raaphorst, J

    2017-07-25

    Non-invasive ventilation (NIV) improves survival and quality of life in amyotrophic lateral sclerosis (ALS) patients. The timing of referral to a home ventilation service (HVS), which is in part based on respiratory function tests, has shown room for improvement. It is currently unknown which respiratory function test predicts an appropriate timing of the initiation of NIV. We analysed, retrospectively, serial data of five respiratory function tests: forced vital capacity (FVC), peak cough flow (PCF), maximum inspiratory and expiratory pressure (MIP and MEP) and sniff nasal inspiratory pressure (SNIP) in patients with ALS. Patients who had had at least one assessment of respiratory function and one visit at the HVS, were included. Our aim was to detect the test with the highest predictive value for the need for elective NIV in the following 3 months. We analysed time curves, currently used cut-off values for referral, and respiratory function test results between 'NIV indication' and 'no-NIV indication' patients. One hundred ten patients with ALS were included of whom 87 received an NIV indication; 11.5% had one assessment before receiving an NIV indication, 88.5% had two or more assessments. The NIV indication was based on complaints of hypoventilation and/or proven (nocturnal) hypercapnia. The five respiratory function tests showed a descending trend during disease progression, where SNIP showed the greatest decline within the latest 3 months before NIV indication (mean = -22%). PCF at the time of referral to the HVS significantly discriminated between the groups 'NIV-indication' and 'no NIV-indication yet' patients at the first HVS visit: 259 (±92) vs. 348 (±137) L/min, p = 0.019. PCF and SNIP showed the best predictive characteristics in terms of sensitivity. SNIP showed the greatest decline prior to NIV indication and PCF significantly differentiated 'NIV-indication' from 'no NIV-indication yet' patients with ALS. Currently used cut-off values might be

  5. Bulk-mediated surface diffusion: non-Markovian desorption and biased behaviour in an infinite system

    International Nuclear Information System (INIS)

    Revelli, Jorge A; Budde, Carlos E; Wio, Horacio S

    2005-01-01

    We analyse the dynamics of adsorbed molecules within the bulk-mediated surface diffusion framework. We consider that the particle's desorption mechanism is characterized by a non-Markovian process, while the particle's adsorption and its motion in the bulk are governed by Markovian dynamics, and include the effect of an external field in the form of a bias in the normal motion to the surface. We study this system for the diffusion of particles in a semi-infinite lattice, analysing the conditional probability to find the system on the reference absorptive plane as well as the surface dispersion as functions of time. The agreement between numerical and analytical asymptotic results is discussed

  6. Experience of long-term use of non-invasive ventilation in motor neuron disease: an interpretative phenomenological analysis.

    Science.gov (United States)

    Ando, Hikari; Chakrabarti, Biswajit; Angus, Robert M; Cousins, Rosanna; Thornton, Everard W; Young, Carolyn A

    2014-03-01

    Although non-invasive ventilation (NIV) can promote quality of life in motor neuron disease (MND), previous studies have disregarded the impact of progression of illness. This study explored how patients' perceptions of NIV treatment evolve over time and how this was reflected in their adherence to NIV. Five patients with MND (male=4, mean age=59 years), from a bigger cohort who were prospectively followed, had multiple post-NIV semistructured interviews, covering more than 12 months, along with ventilator interaction data. The transcribed phenomenological data were analysed using qualitative methodology. Three themes emerged: experience of NIV, influence on attitudes and perceived impact of NIV on prognosis. The ventilator interaction data identified regular use of NIV by four participants who each gave positive account of their experience of NIV treatment, and irregular use by one participant who at interview revealed a negative attitude to NIV treatment and in whom MND induced feelings of hopelessness. This exploratory study suggests that a positive coping style, adaptation and hope are key factors for psychological well-being and better adherence to NIV. More studies are needed to determine these relationships.

  7. Test equipment for a flywheel energy storage system using a magnetic bearing composed of superconducting coils and superconducting bulks

    International Nuclear Information System (INIS)

    Ogata, M; Matsue, H; Yamashita, T; Hasegawa, H; Nagashima, K; Maeda, T; Matsuoka, T; Mukoyama, S; Shimizu, H; Horiuchi, S

    2016-01-01

    Energy storage systems are necessary for renewable energy sources such as solar power in order to stabilize their output power, which fluctuates widely depending on the weather. Since ‘flywheel energy storage systems’ (FWSSs) do not use chemical reactions, they do not deteriorate due to charge or discharge. This is an advantage of FWSSs in applications for renewable energy plants. A conventional FWSS has capacity limitation because of the mechanical bearings used to support the flywheel. Therefore, we have designed a superconducting magnetic bearing composed of a superconducting coil stator and a superconducting bulk rotor in order to solve this problem, and have experimentally manufactured a large scale FWSS with a capacity of 100 kWh and an output power of 300 kW. The superconducting magnetic bearing can levitate 4 tons and enables the flywheel to rotate smoothly. A performance confirmation test will be started soon. An overview of the superconducting FWSS is presented in this paper. (paper)

  8. Ventilation systems

    International Nuclear Information System (INIS)

    Gossler

    1980-01-01

    The present paper deals with - controlled area ventilation systems - ventilation systems for switchgear-building and control-room - other ventilation systems for safety equipments - service systems for ventilation systems. (orig./RW)

  9. Omnidirectional ventilated acoustic barrier

    Science.gov (United States)

    Zhang, Hai-long; Zhu, Yi-fan; Liang, Bin; Yang, Jing; Yang, Jun; Cheng, Jian-chun

    2017-11-01

    As an important problem in acoustics, sound insulation finds applications in a great variety of situations. In the existing schemes, however, there has always been a trade-off between the thinness of sound-insulating devices and their ventilating capabilities, limiting their potentials in the control of low-frequency sound in high ventilation environments. Here, we design and experimentally implement an omnidirectional acoustic barrier with a planar profile, subwavelength thickness ( 0.18 λ ), yet high ventilation. The proposed mechanism is based on the interference between the resonant scattering of discrete states and the background scattering of continuous states which induces a Fano-like asymmetric transmission profile. Benefitting from the binary-structured design of the coiled unit and hollow pipe, it maximally simplifies the design and fabrication while ensuring the ventilation for all the non-resonant units with open tubes. The simulated and measured results agree well, showing the effectiveness of our proposed mechanism to block low frequency sound coming from various directions while allowing 63% of the air flow to pass. We anticipate our design to open routes to design sound insulators and to enable applications in traditionally unattainable cases such as those calling for noise reduction and cooling simultaneously.

  10. TVENT: a computer program for analysis of tornado-induced transients in ventilation systems

    International Nuclear Information System (INIS)

    Duerre, K.H.; Andrae, R.W.; Gregory, W.S.

    1978-07-01

    The report describes TVENT, a portable FORTRAN computer program for predicting flows and pressures in a ventilation system subject to a tornado. The pressure and flow values calculated by TVENT can be used as a basis for structural analysis. TVENT is a one-dimensional, lumped-parameter model with incompressible flow augmented by fluid storage. The theoretical basis for the mathematical modeling and analysis is presented, and a description of the input for the computer code is provided. Modeling techniques specific to ventilation systems are described. Sample problems illustrate the use of TVENT in analyzing ventilation systems. Other sample problems illustrate modeling techniques used in reducing complex systems

  11. Mechanical Ventilation

    Science.gov (United States)

    ... ventilation is a life support treatment. A mechanical ventilator is a machine that helps people breathe when ... to breathe enough on their own. The mechanical ventilator is also called a ventilator , respirator, or breathing ...

  12. Initial computer modeling of WIPP [Waste Isolation Pilot Plant] underground ventilation system, September 1985--March 1986

    International Nuclear Information System (INIS)

    Sethi, S.

    1986-11-01

    Provision of a good ventilation system has been and continues to be a major priority here of those responsible for its design, management, and operation. As an ongoing effort in this direction, development of computer simulated models for the system was initiated in September, 1985. It was decided to utilize Dravo's 'MINEVENT' computer program for this purpose. Accordingly, initial computer models of the mine's ventilation system have been developed for various modes of operation. Specifically, they include: Simulation of the current ventilation system, and Simulation of the designed ventilation system for modes: mine construction mode/shift, waste storage mode/shift, and air reversal mode. 5 figs

  13. Is the effect of non-invasive ventilation on survival in amyotrophic lateral sclerosis age-dependent?

    OpenAIRE

    Siirala, Waltteri; Aantaa, Riku; Olkkola, Klaus T; Saaresranta, Tarja; Vuori, Arno

    2013-01-01

    Background Hypoventilation due to respiratory muscle atrophy is the most common cause of death as a result of amyotrophic lateral sclerosis (ALS). Patients aged over 65?years and presenting bulbar symptoms are likely to have a poorer prognosis. The aim of the study was to assess the possible impact of age and treatment with non-invasive ventilation (NIV) on survival in ALS. Based on evidence from earlier studies, it was hypothesized that NIV increases rates of survival regardless of age. Meth...

  14. Ventilation-perfused studies using SPECT

    International Nuclear Information System (INIS)

    Zwijnenburg, A.

    1989-01-01

    A method for the quantitative analysis of ventilation-perfusion SPECT studies is decribed and an effort is made to evaluate its usefullness. The technical details of the emthod are described. In the the transaxial reconstructions of the tomographic studies the contour of the lungs is detected and regional values of lung volume, ventilation, perfusion and ventilation-perfusion ratios are calculated. The method is operator independent. The lung volume calculations from the SPECT studies are validated by comparing them with lung volume measurements using the helium dilution technique. A good correlation (r=0.91) was found between the two volumes. SPECT volume was greater than the volume measured with helium dilution, which was attributed to non-gas-containing structures in the. lungs. The use of ventilation-perfusion ratio SPECT is described to evaluate the effect of ionizing radiation on the lungs in patients treated with mantle field irradiation for Hodgkin's disease. Perfusion changes appear as early as 2 months after the start of irradiation. Ventilation changes appear later and relatively minor. No changes are seen outside the radiation portals. The ventilation-perfusion inequality in pulmonary sarcoidosis is treated. It is suggested that the decrease D LCO in these patients may be partly due to an even distribution of ventilation perfusion ratios. An effort is made to establish the properties of a new tracer used for the assessment of the metabolic function of the pulmonary endothelium. The lung uptake of I-123 IMP mimics the distribution of a perfusion tracer and it is suggested that this tracer may be useful for the early detection of pulmonary vascular damage, even when blood flow is still intact. Some aspects of the use of Kr-81m as a ventilation tracer are discussed as well as the effect of noise on Kr-81m SPECT reconstructions. (author). 146 refs.; 39 figs.; 8 tabs

  15. An evaluation of instruments for scoring physiological and behavioral cues of pain, non-pain related distress, and adequacy of analgesia and sedation in pediatric mechanically ventilated patients: A systematic review.

    Science.gov (United States)

    Dorfman, Tamara L; Sumamo Schellenberg, Elizabeth; Rempel, Gwen R; Scott, Shannon D; Hartling, Lisa

    2014-04-01

    Advancing technology allows for successful treatment of children with life-threatening illnesses. Effectively assessing and optimally treating a child's distress during their stay in the Pediatric Intensive Care Unit (PICU) is paramount. Objective measures of distress in mechanically ventilated pediatric patients are increasingly available but few have been evaluated. The objectives of this systematic review were to identify available instruments appropriate for measuring physiological and behavioral cues of pain, non-pain related distress, and adequacy of analgesia and sedation in mechanically ventilated pediatric patients, and evaluate these instruments in terms of their psychometric properties. A systematic review of original and validation reports of objective instruments to measure pain and non-pain related distress, and adequacy of analgesia and sedation in mechanically ventilated PICU patients was undertaken. A comprehensive search was conducted in 10 databases from January 1970 to June 2011. Reference lists of relevant articles were reviewed to identify additional articles. Studies were included in the review if they met pre-established eligibility criteria. Two independent reviewers reviewed studies for inclusion, assessed quality, and extracted data. Twenty-five articles were included, identifying 15 instruments. The instruments had different foci including: assessing pain, non-pain related distress, and sedation (n=2); assessing pain exclusively (n=4); assessing sedation exclusively (n=7), assessing sedation in mechanically ventilated muscle relaxed PICU patients (n=1); and assessing delirium in mechanically ventilated PICU patients (n=1). The Comfort Scale demonstrated the greatest clinical utility in the assessment of pain, non-pain related distress, and sedation in mechanically ventilated pediatric patients. Modified FLACC and the MAPS are more appropriate, however, for the assessment of procedural pain and other brief painful events. More work is

  16. Evaluation of the long duration efficiency of the ECC storage facility of Cogema La Hague plant

    International Nuclear Information System (INIS)

    Baganz, C.; Bouland, P.; Breton, E.

    2004-01-01

    The ECC facility of Cogema La Hague has been designed in view of the storage of 24000 CSD-C type containers produced by the ACC facility. It comprises a reception and unloading unit, and a modular storage unit (alveoles). The safety of the facility is based on: a controlled ventilation (low pressurization rooms, controlled atmosphere, heat and toxic gases evacuation), a construction ensuring the static confinement, the sub-criticality and the radiological protection, and the possibility of natural ventilation of the alveoles (earthquake-dimensioned equipments). On the basis of these safety functions, the conformability of the facility with respect to long duration has been analyzed considering three aspects of the facility: the infrastructure, the waste packages and the ventilation system. In normal operation, a foreseeable service life of at least 100 years is established: simpleness and accessibility of ventilation systems, no significant corrosion of packages, durability of the reinforced concrete structure. The demonstration of a service life greater than 100 years would require the improvement of our knowledge about concretes in terms of experience feedback. The behaviour of the facility in terms of loss of technical mastery has been considered too. The scenario retained for this situation is the prolonged stoppage (several months or years) of the nuclear ventilation after a 100 years of disposal. After this period of time, both the thermal power and the hydrogen generation from waste packages will have significantly diminished, allowing a loss of technical mastery era of several years with no impact on concretes integrity. However, during long situations of non-controlled atmosphere, the corrosion behaviour of stainless steels is not predictable. (J.S.)

  17. No damage to bulk storage but entire customer bases wiped out in storm

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper reports that interviews with key LP-gas industry spokesmen in hurricane-ravaged South Florida following Andrew's terrifying visit presented a picture of unimaginable destruction and nearly immeasurable losses of property but miraculously, not a single significant incident involving leaks or the loss of bulk storage. In the worst reports of damage to propane company facilities, Homestead Gas loss at least one building and the Suburban/Petrolane office building in Homestead no longer exists. (Temporary office arrangements were established by Suburban/Petrolane.) The customer base of these companies has been hit very had. For a while, it appeared that one Suburban/Petrolane employee was unaccounted for but that report turned out to be false. Shortly after the storm, crews were out securing gas systems in whatever locations they could reach. In one instance in which regular travel proved impossible, the gas company was forced to travel the long way around-pulling resources out of its Key West district and going north to Homestead. It became necessary in many cases for personnel to purchase cellular phones in order to maintain contact between the office and field crew

  18. Performance of mechanical ventilators at the patient's home: a multicentre quality control study.

    Science.gov (United States)

    Farré, R; Navajas, D; Prats, E; Marti, S; Guell, R; Montserrat, J M; Tebe, C; Escarrabill, J

    2006-05-01

    Quality control procedures vary considerably among the providers of equipment for home mechanical ventilation (HMV). A multicentre quality control survey of HMV was performed at the home of 300 patients included in the HMV programmes of four hospitals in Barcelona. It consisted of three steps: (1) the prescribed ventilation settings, the actual settings in the ventilator control panel, and the actual performance of the ventilator measured at home were compared; (2) the different ventilator alarms were tested; and (3) the effect of differences between the prescribed settings and the actual performance of the ventilator on non-programmed readmissions of the patient was determined. Considerable differences were found between actual, set, and prescribed values of ventilator variables; these differences were similar in volume and pressure preset ventilators. The percentage of patients with a discrepancy between the prescribed and actual measured main ventilator variable (minute ventilation or inspiratory pressure) of more than 20% and 30% was 13% and 4%, respectively. The number of ventilators with built in alarms for power off, disconnection, or obstruction was 225, 280 and 157, respectively. These alarms did not work in two (0.9%), 52 (18.6%) and eight (5.1%) ventilators, respectively. The number of non-programmed hospital readmissions in the year before the study did not correlate with the index of ventilator error. This study illustrates the current limitations of the quality control of HMV and suggests that improvements should be made to ensure adequate ventilator settings and correct ventilator performance and ventilator alarm operation.

  19. Displacement ventilation

    DEFF Research Database (Denmark)

    Kosonen, Risto; Melikov, Arsen Krikor; Mundt, Elisabeth

    The aim of this Guidebook is to give the state-of-the art knowledge of the displacement ventilation technology, and to simplify and improve the practical design procedure. The Guidebook discusses methods of total volume ventilation by mixing ventilation and displacement ventilation and it gives...... insights of the performance of the displacement ventilation. It also shows practical case studies in some typical applications and the latest research findings to create good local micro-climatic conditions....

  20. Battery life of portable home ventilators: effects of ventilator settings.

    Science.gov (United States)

    Falaize, Line; Leroux, Karl; Prigent, Hélène; Louis, Bruno; Khirani, Sonia; Orlikowski, David; Fauroux, Brigitte; Lofaso, Frédéric

    2014-07-01

    The battery life (BL) of portable home ventilator batteries is reported by manufacturers. The aim of this study was to evaluate the effects of ventilator mode, breathing frequency, PEEP, and leaks on the BL of 5 commercially available portable ventilators. The effects of the ventilator mode (volume controlled-continuous mandatory ventilation [VC-CMV] vs pressure support ventilation [PSV]), PEEP 5 cm H2O, breathing frequency (10, 15, and 20 breaths/min), and leaks during both volume-targeted ventilation and PSV on the BL of 5 ventilators (Elisée 150, Monnal T50, PB560, Vivo 50, and Trilogy 100) were evaluated. Each ventilator was ventilated with a test lung at a tidal volume of 700 ml and an inspiratory time of 1.2 s in the absence of leaks. Switching from PSV to VC-CMV or the addition of PEEP did not significantly change ventilator BL. The increase in breathing frequency from 10 to 20 breaths/min decreased the BL by 18 ± 11% (P = .005). Leaks were associated with an increase in BL during the VC-CMV mode (18 ± 20%, P = .04) but a decrease in BL during the PSV mode (-13 ± 15%, P = .04). The BL of home ventilators depends on the ventilator settings. BL is not affected by the ventilator mode (VC-CMV or PSV) or the addition of PEEP. BL decreases with an increase in breathing frequency and during leaks with a PSV mode, whereas leaks increase the duration of ventilator BL during VC-CMV. Copyright © 2014 by Daedalus Enterprises.

  1. VENTILATION MODEL

    International Nuclear Information System (INIS)

    V. Chipman

    2002-01-01

    The purpose of the Ventilation Model is to simulate the heat transfer processes in and around waste emplacement drifts during periods of forced ventilation. The model evaluates the effects of emplacement drift ventilation on the thermal conditions in the emplacement drifts and surrounding rock mass, and calculates the heat removal by ventilation as a measure of the viability of ventilation to delay the onset of peak repository temperature and reduce its magnitude. The heat removal by ventilation is temporally and spatially dependent, and is expressed as the fraction of heat carried away by the ventilation air compared to the fraction of heat produced by radionuclide decay. One minus the heat removal is called the wall heat fraction, or the remaining amount of heat that is transferred via conduction to the surrounding rock mass. Downstream models, such as the ''Multiscale Thermohydrologic Model'' (BSC 2001), use the wall heat fractions as outputted from the Ventilation Model to initialize their postclosure analyses

  2. Cardiac function associated with home ventilator care in Duchenne muscular dystrophy.

    Science.gov (United States)

    Lee, Sangheun; Lee, Heeyoung; Eun, Lucy Youngmin; Gang, Seung Woong

    2018-02-01

    Cardiomyopathy is becoming the leading cause of death in patients with Duchenne muscular dystrophy because mechanically assisted lung ventilation and assisted coughing have helped resolve respiratory complications. To clarify cardiopulmonary function, we compared cardiac function between the home ventilator-assisted and non-ventilator-assisted groups. We retrospectively reviewed patients with Duchenne muscular dystrophy from January 2010 to March 2016 at Gangnam Severance Hospital. Demographic characteristics, pulmonary function, and echocardiography data were investigated. Fifty-four patients with Duchenne muscular dystrophy were divided into 2 groups: home ventilator-assisted and non-ventilator-assisted. The patients in the home ventilator group were older (16.25±1.85 years) than those in the nonventilator group (14.73±1.36 years) ( P =0.001). Height, weight, and body surface area did not differ significantly between groups. The home ventilator group had a lower seated functional vital capacity (1,038±620.41 mL) than the nonventilator group (1,455±603.12 mL). Mean left ventricular ejection fraction and fractional shortening were greater in the home ventilator group, but the data did not show any statistical difference. The early ventricular filling velocity/late ventricular filling velocity ratio (1.7±0.44) was lower in the home ventilator group than in the nonventilator group (2.02±0.62). The mitral valve annular systolic velocity was higher in the home ventilator group (estimated β, 1.06; standard error, 0.48). Patients with Duchenne muscular dystrophy on a ventilator may have better systolic and diastolic cardiac functions. Noninvasive ventilator assistance can help preserve cardiac function. Therefore, early utilization of noninvasive ventilation or oxygen may positively influence cardiac function in patients with Duchenne muscular dystrophy.

  3. Demand Response and Energy Storage Integration Study

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Ookie; Cheung, Kerry; Olsen, Daniel J.; Matson, Nance; Sohn, Michael D.; Rose, Cody M.; Dudley, Junqiao Han; Goli, Sasank; Kiliccote, Sila; Cappers, Peter; MacDonald, Jason; Denholm, Paul; Hummon, Marissa; Jorgenson, Jennie; Palchak, David; Starke, Michael; Alkadi, Nasr; Bhatnagar, Dhruv; Currier, Aileen; Hernandez, Jaci; Kirby, Brendan; O' Malley, Mark

    2016-03-01

    Demand response and energy storage resources present potentially important sources of bulk power system services that can aid in integrating variable renewable generation. While renewable integration studies have evaluated many of the challenges associated with deploying large amounts of variable wind and solar generation technologies, integration analyses have not yet fully incorporated demand response and energy storage resources. This report represents an initial effort in analyzing the potential integration value of demand response and energy storage, focusing on the western United States. It evaluates two major aspects of increased deployment of demand response and energy storage: (1) Their operational value in providing bulk power system services and (2) Market and regulatory issues, including potential barriers to deployment.

  4. Identifying Non-Volatile Data Storage Areas: Unique Notebook Identification Information as Digital Evidence

    Directory of Open Access Journals (Sweden)

    Nikica Budimir

    2007-03-01

    Full Text Available The research reported in this paper introduces new techniques to aid in the identification of recovered notebook computers so they may be returned to the rightful owner. We identify non-volatile data storage areas as a means of facilitating the safe storing of computer identification information. A forensic proof of concept tool has been designed to test the feasibility of several storage locations identified within this work to hold the data needed to uniquely identify a computer. The tool was used to perform the creation and extraction of created information in order to allow the analysis of the non-volatile storage locations as valid storage areas capable of holding and preserving the data created within them.  While the format of the information used to identify the machine itself is important, this research only discusses the insertion, storage and ability to retain such information.

  5. Hypoventilation improvement in an adult non-invasively ventilated patient with Rapid-onset Obesity with Hypothalamic Dysfunction Hypoventilation and Autonomic Dysregulation (ROHHAD).

    Science.gov (United States)

    Graziani, Alessandro; Casalini, Pierpaolo; Mirici-Cappa, Federica; Pezzi, Giuseppe; Giuseppe Stefanini, Francesco

    2016-01-01

    Rapid-onset Obesity with Hypothalamic Dysfunction, Hypoventilation, and Autonomic Dysregulation (ROHHAD) is a rare disease of unknown etiology, characterized by rapid-onset obesity in young children, hypoventilation, hypothalamic and autonomic dysfunction. Patients between the ages of 2 and 4 present with hyperphagia and weight gain, followed by neuro-hormonal dysfunction and central hypoventilation months or years later. Cardiac arrest may represent the fatal complication of alveolar hypoventilation and early mechanical ventilation is essential for the patient's life. In this paper, we describe a 22-year-old patient with ROHHAD syndrome who had an acute respiratory failure during nocturnal non-invasive ventilation (NIV).

  6. Patient-Ventilator Dyssynchrony

    Directory of Open Access Journals (Sweden)

    Elvira-Markela Antonogiannaki

    2017-11-01

    Full Text Available In mechanically ventilated patients, assisted mechanical ventilation (MV is employed early, following the acute phase of critical illness, in order to eliminate the detrimental effects of controlled MV, most notably the development of ventilator-induced diaphragmatic dysfunction. Nevertheless, the benefits of assisted MV are often counteracted by the development of patient-ventilator dyssynchrony. Patient-ventilator dyssynchrony occurs when either the initiation and/or termination of mechanical breath is not in time agreement with the initiation and termination of neural inspiration, respectively, or if the magnitude of mechanical assist does not respond to the patient’s respiratory demand. As patient-ventilator dyssynchrony has been associated with several adverse effects and can adversely influence patient outcome, every effort should be made to recognize and correct this occurrence at bedside. To detect patient-ventilator dyssynchronies, the physician should assess patient comfort and carefully inspect the pressure- and flow-time waveforms, available on the ventilator screen of all modern ventilators. Modern ventilators offer several modifiable settings to improve patient-ventilator interaction. New proportional modes of ventilation are also very helpful in improving patient-ventilator interaction.

  7. Cardiopulmonary function and oxygen delivery during total liquid ventilation.

    Science.gov (United States)

    Tsagogiorgas, Charalambos; Alb, Markus; Herrmann, Peter; Quintel, Michael; Meinhardt, Juergen P

    2011-10-01

    Total liquid ventilation (TLV) with perfluorocarbons has shown to improve cardiopulmonary function in the injured and immature lung; however there remains controversy over the normal lung. Hemodynamic effects of TLV in the normal lung currently remain undetermined. This study compared changes in cardiopulmonary and circulatory function caused by either liquid or gas tidal volume ventilation. In a prospective, controlled study, 12 non-injured anesthetized, adult New Zealand rabbits were primarily conventionally gas-ventilated (CGV). After instrumentation for continuous recording of arterial (AP), central venous (CVP), left artrial (LAP), pulmonary arterial pressures (PAP), and cardiac output (CO) animals were randomized into (1) CGV group and (2) TLV group. In the TLV group partial liquid ventilation was initiated with instillation of perfluoroctylbromide (12 ml/kg). After 15 min, TLV was established for 3 hr applying a volume-controlled, pressure-limited, time-cycled ventilation mode using a double-piston configured TLV. Controls (CGV) remained gas-ventilated throughout the experiment. During TLV, heart rate, CO, PAP, MAP, CVP, and LAP as well as derived hemodynamic variables, arterial and mixed venous blood gases, oxygen delivery, PVR, and SVR did not differ significantly compared to CGV. Liquid tidal volumes suitable for long-term TLV in non-injured rabbits do not significantly impair CO, blood pressure, and oxygen dynamics when compared to CGV. Copyright © 2011 Wiley-Liss, Inc.

  8. Defining sale ethylene for long term storage of tulip bulbs

    NARCIS (Netherlands)

    Wild, de H.P.J.; Peppelenbos, H.W.; Dijkstra, M.H.G.E.; Gude, H.

    2002-01-01

    The maximum ethylene level that can be permitted in storage rooms, without causing damage to tulip bulbs, is not exactly known. Therefore, a zero-tolerance for the presence of ethylene during storage of tulip bulbs is common practice. This results in excessive ventilation and coherent large energy

  9. Research and development project for flywheel energy storage system using high-temperature superconducting magnetic bearing

    International Nuclear Information System (INIS)

    Shinagawa, Jiro; Ishikawa, Fumihiko

    1996-01-01

    Recent progress in the research and development of an yttrium-based oxide high-temperature superconductor has enabled the production of a large-diameter bulk with a strong flux-pinning force. A combination of this superconductor and a permanent magnet makes it feasible to fabricate a non-contact, non-controlled superconducting magnetic bearing with a very small rotational loss. Use of the superconducting magnetic bearing for a flywheel energy storage system may pave the way to the development of a new energy storage system that has great energy storage efficiency. >From relevant data measured with a miniature model of the high-temperature superconducting magnetic bearing, a conceptual design of an 8 MWh flywheel energy storage system was developed, using the new bearing which proved to be potentially capable of achieving a high energy storage efficiency of 84%. A 100 Wh-class experimental system was install that attained a high revolution rate of 17.000 rpm. (author)

  10. Demand Controlled Ventilation in a Combined Ventilation and Radiator System

    OpenAIRE

    Hesaraki, Arefeh; Holmberg, Sture

    2013-01-01

    With growing concerns for efficient and sustainable energy treatment in buildings there is a need for balanced and intelligent ventilation solutions. This paper presents a strategy for demand controlled ventilation with ventilation radiators, a combined heating and ventilation system. The ventilation rate was decreased from normal requirements (per floor area) of 0.375 l·s-1·m-2 to 0.100 l·s-1·m-2 when the residence building was un-occupied. The energy saving potential due to decreased ventil...

  11. [Lung protective ventilation. Ventilatory modes and ventilator parameters].

    Science.gov (United States)

    Schädler, Dirk; Weiler, Norbert

    2008-06-01

    Mechanical ventilation has a considerable potential for injuring the lung tissue. Therefore, attention has to be paid to the proper choice of ventilatory mode and settings to secure lung-protective ventilation whenever possible. Such ventilator strategy should account for low tidal volume ventilation (6 ml/kg PBW), limited plateau pressure (30 to 35 cm H2O) and positive end-expiratory pressure (PEEP). It is unclear whether pressure controlled or volume controlled ventilation with square flow profile is beneficial. The adjustment of inspiration and expiration time should consider the actual breathing mechanics and anticipate the generation of intrinsic PEEP. Ventilatory modes with the possibility of supporting spontaneous breathing should be used as soon as possible.

  12. Variable mechanical ventilation.

    Science.gov (United States)

    Fontela, Paula Caitano; Prestes, Renata Bernardy; Forgiarini, Luiz Alberto; Friedman, Gilberto

    2017-01-01

    To review the literature on the use of variable mechanical ventilation and the main outcomes of this technique. Search, selection, and analysis of all original articles on variable ventilation, without restriction on the period of publication and language, available in the electronic databases LILACS, MEDLINE®, and PubMed, by searching the terms "variable ventilation" OR "noisy ventilation" OR "biologically variable ventilation". A total of 36 studies were selected. Of these, 24 were original studies, including 21 experimental studies and three clinical studies. Several experimental studies reported the beneficial effects of distinct variable ventilation strategies on lung function using different models of lung injury and healthy lungs. Variable ventilation seems to be a viable strategy for improving gas exchange and respiratory mechanics and preventing lung injury associated with mechanical ventilation. However, further clinical studies are necessary to assess the potential of variable ventilation strategies for the clinical improvement of patients undergoing mechanical ventilation.

  13. Hydrogen transport and storage in engineered glass microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Rambach, G.D.

    1995-02-28

    New, high strength glass microspheres filled with pressurized hydrogen exhibit densities which make them attractive for bulk hydrogen storage and transport. The membrane tensile stress at failure for engineered glass microspheres is about 150,000 psi, permitting a three-fold increase in pressure limit and storage capacity above commercial microspheres, which have been studied a decade ago and have been shown to fail at membrane stresses of 50,000 psi. This analysis relating glass microspheres for hydrogen transport with infrastructure and economics, indicate that pressurized microspheres can be economically competitive with other forms of bulk rail and truck transport such as pressurized tube transports and liquid hydrogen trailers. This paper will describe the matching of current glass microspheres with the useful application in commercial hydrogen bulk transport and storage.

  14. Non-Smoker Exposure to Secondhand Cannabis Smoke II: Effect of Room Ventilation on the Physiological, Subjective, and Behavioral/Cognitive Effects

    Science.gov (United States)

    Herrmann, Evan S.; Cone, Edward J; Mitchell, John M.; Bigelow, George E.; LoDico, Charles; Flegel, Ron; Vandrey, Ryan

    2015-01-01

    Introduction Cannabis is the most widely used illicit drug. Many individuals are incidentally exposed to secondhand cannabis smoke, but little is known about the effects of this exposure. This report examines the physiological, subjective, and behavioral/cognitive effects of secondhand cannabis exposure, and the influence of room ventilation on these effects. Methods Non-cannabis-using individuals were exposed to secondhand cannabis smoke from six individuals smoking cannabis (11.3% THC) ad libitum in a specially constructed chamber for one hour. Chamber ventilation was experimentally manipulated so that participants were exposed under unventilated conditions or with ventilation at a rate of 11 air exchanges/hour. Physiological, subjective and behavioral/cognitive measures of cannabis exposure assessed after exposure sessions were compared to baseline measures. Results Exposure to secondhand cannabis smoke under unventilated conditions produced detectable cannabinoid levels in blood and urine, minor increases in heart rate, mild to moderate self-reported sedative drug effects, and impaired performance on the Digit Symbol Substitution Task (DSST). One urine specimen tested positive at using a 50 ng/mL cut-off and several specimens were positive at 20 ng/mL. Exposure under ventilated conditions resulted in much lower blood cannabinoid levels, and did not produce sedative drug effects, impairments in performance, or positive urine screen results. Conclusions Room ventilation has a pronounced effect on exposure to secondhand cannabis smoke. Under extreme, unventilated conditions, secondhand cannabis smoke exposure can produce detectable levels of THC in blood and urine, minor physiological and subjective drug effects, and minor impairment on a task requiring psychomotor ability and working memory. PMID:25957157

  15. Mine ventilation engineering

    Energy Technology Data Exchange (ETDEWEB)

    Hall, C.J.

    1981-01-01

    This book on mine ventilation covers psychometrics, airflow through roadways and ducts, natural ventilation, fans, instruments, ventilation surveys, auxiliary ventilation, air quality, and planning and economics.

  16. Meeting Residential Ventilation Standards Through Dynamic Control of Ventilation Systems

    OpenAIRE

    Sherman, Max H.

    2011-01-01

    Existing ventilation standards, including American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE) Standard 62.2, specify continuous operation of a defined mechanical ventilation system to provide minimum ventilation, with time-based intermittent operation as an option. This requirement ignores several factors and concerns including: other equipment such as household exhaust fans that might incidentally provide ventilation, negative impacts of ventilation when outd...

  17. Successful 1:1 proportion ventilation with a unique device for independent lung ventilation using a double-lumen tube without complications in the supine and lateral decubitus positions. A pilot study.

    Directory of Open Access Journals (Sweden)

    Michał Kowalczyk

    Full Text Available Adequate blood oxygenation and ventilation/perfusion matching should be main goal of anaesthetic and intensive care management. At present, one of the methods of improving gas exchange restricted by ventilation/perfusion mismatching is independent ventilation with two ventilators. Recently, however, a unique device has been developed, enabling ventilation of independent lungs in 1:1, 2:1, 3:1, and 5:1 proportions. The main goal of the study was to evaluate the device's utility, precision and impact on pulmonary mechanics. Secondly- to measure the gas distribution in supine and lateral decubitus position.69 patients who underwent elective thoracic surgery were eligible for the study. During general anaesthesia, after double lumen tube intubation, the aforementioned control system was placed between the anaesthetic machine and the patient. In the supine and lateral decubitus (left/right positions, measurements of conventional and independent (1:1 proportion ventilation were performed separately for each lung, including the following: tidal volume, peak pressure and dynamic compliance.Our results show that conventional ventilation using Robertshaw tube in the supine position directs 47% of the tidal volume to the left lung and 53% to the right lung. Furthermore, in the left lateral position, 44% is directed to the dependent lung and 56% to the non-dependent lung. In the right lateral position, 49% is directed to the dependent lung and 51% to the non-dependent lung. The control system positively affected non-dependent and dependent lung ventilation by delivering equal tidal volumes into both lungs with no adverse effects, regardless of patient's position.We report that gas distribution is uneven during conventional ventilation using Robertshaw tube in the supine and lateral decubitus positions. However, this recently released control system enables precise and safe independent ventilation in the supine and the left and right lateral decubitus

  18. Non-minimal derivative coupling scalar field and bulk viscous dark energy

    Energy Technology Data Exchange (ETDEWEB)

    Mostaghel, Behrang [Shahid Beheshti University, Department of Physics, Tehran (Iran, Islamic Republic of); Moshafi, Hossein [Institute for Advanced Studies in Basic Sciences, Department of Physics, Zanjan (Iran, Islamic Republic of); Movahed, S.M.S. [Shahid Beheshti University, Department of Physics, Tehran (Iran, Islamic Republic of); Institute for Research in Fundamental Sciences (IPM), School of Physics, Tehran (Iran, Islamic Republic of)

    2017-08-15

    Inspired by thermodynamical dissipative phenomena, we consider bulk viscosity for dark fluid in a spatially flat two-component Universe. Our viscous dark energy model represents phantom-crossing which avoids big-rip singularity. We propose a non-minimal derivative coupling scalar field with zero potential leading to accelerated expansion of the Universe in the framework of bulk viscous dark energy model. In this approach, the coupling constant, κ, is related to viscosity coefficient, γ, and the present dark energy density, Ω{sub DE}{sup 0}. This coupling is bounded as κ element of [-1/9H{sub 0}{sup 2}(1 - Ω{sub DE}{sup 0}), 0]. We implement recent observational data sets including a joint light-curve analysis (JLA) for SNIa, gamma ray bursts (GRBs) for most luminous astrophysical objects at high redshifts, baryon acoustic oscillations (BAO) from different surveys, Hubble parameter from HST project, Planck CMB power spectrum and lensing to constrain model free parameters. The joint analysis of JLA + GRBs + BAO + HST shows that Ω{sub DE}{sup 0} = 0.696 ± 0.010, γ = 0.1404 ± 0.0014 and H{sub 0} = 68.1 ± 1.3. Planck TT observation provides γ = 0.32{sup +0.31}{sub -0.26} in the 68% confidence limit for the viscosity coefficient. The cosmographic distance ratio indicates that current observed data prefer to increase bulk viscosity. The competition between phantom and quintessence behavior of the viscous dark energy model can accommodate cosmological old objects reported as a sign of age crisis in the ΛCDM model. Finally, tension in the Hubble parameter is alleviated in this model. (orig.)

  19. Application of non-invasive mechanical ventilation in an asthmatic pregnant woman in respiratory failure: a case report

    Science.gov (United States)

    Caner, Hanife; Eryuksel, Emel; Kosar, Filiz

    2013-01-01

    The use of non-invasive mechanical ventilation (NIV) during an asthma attack is controversial. We report a case of a 28-year-old female patient in her 16th week of pregnancy with community-acquired pneumonia who presented during an asthma attack, which led to hypoxic respiratory failure. She was successfully treated using NIV. This case is worth discussing as it includes two clinical conditions in which NIV is often considered contraindicated. PMID:23372957

  20. Application of non-invasive mechanical ventilation in an asthmatic pregnant woman in respiratory failure: a case report

    OpenAIRE

    Dalar, Levent; Caner, Hanife; Eryuksel, Emel; Kosar, Filiz

    2013-01-01

    The use of non-invasive mechanical ventilation (NIV) during an asthma attack is controversial. We report a case of a 28-year-old female patient in her 16th week of pregnancy with community-acquired pneumonia who presented during an asthma attack, which led to hypoxic respiratory failure. She was successfully treated using NIV. This case is worth discussing as it includes two clinical conditions in which NIV is often considered contraindicated.

  1. Exposure to aerosol and gaseous pollutants in a room ventilated with mixing air distribution

    DEFF Research Database (Denmark)

    Bivolarova, Mariya Petrova; Ondráček, Jakub; Ždímal, Vladimír

    2016-01-01

    The present study investigates the aerosol and gas dispersal in a mechanically ventilated room and the personal exposure to these contaminants. The study was performed in a full-scale climate chamber. The room was air conditioned via mixing total volume ventilation system. The room occupancy was ...... of the thermal manikin were measured. The results showed higher exposure to the contaminants measured at the breathing zone than at the ambient air. The behaviour of the tracer gas and the aerosols was similar.......The present study investigates the aerosol and gas dispersal in a mechanically ventilated room and the personal exposure to these contaminants. The study was performed in a full-scale climate chamber. The room was air conditioned via mixing total volume ventilation system. The room occupancy...... was simulated by a sitting dressed thermal manikin with realistic body shape. During the experiments monodisperse aerosols of three sizes and nitrous oxide tracer gas were generated simultaneously from one location in the room. The aerosol and gas concentrations in the bulk room air and in the breathing zone...

  2. Position paper -- Waste storage tank heat removal

    International Nuclear Information System (INIS)

    Stine, M.D.

    1995-01-01

    The purpose of this paper is to develop and document a position on the heat removal system to be used on the waste storage tanks currently being designed for the Multi-Function Waste Tank Facility (MWTF), project W-236A. The current preliminary design for the waste storage primary tank heat removal system consists of the following subsystems: (1) a once-through dome space ventilation system; (2) a recirculation dome space ventilation system; and (3) an annulus ventilation system. Recently completed and ongoing studies have evaluated alternative heat removal systems in an attempt to reduce system costs and to optimize heat removal capabilities. In addition, a thermal/heat transfer analysis is being performed that will provide assurance that the heat removal systems selected will be capable of removing the total primary tank design heat load of 1.25 MBtu/hr at an allowable operating temperature of 190 F. Although 200 F is the design temperature limit, 190 F has been selected as the maximum allowable operating temperature limit based on instrumentation sensitivity, instrumentation location sensitivity, and other factors. Seven options are discussed and recommendations are made

  3. Magnetic Resonance Imaging of Ventilation and Perfusion in the Lung

    Science.gov (United States)

    Prisk, Gordon Kim (Inventor); Hopkins, Susan Roberta (Inventor); Buxton, Richard Bruce (Inventor); Pereira De Sa, Rui Carlos (Inventor); Theilmann, Rebecca Jean (Inventor); Cronin, Matthew Vincent (Inventor)

    2017-01-01

    Methods, devices, and systems are disclosed for implementing a fully quantitative non-injectable contrast proton MRI technique to measure spatial ventilation-perfusion (VA/Q) matching and spatial distribution of ventilation and perfusion. In one aspect, a method using MRI to characterize ventilation and perfusion in a lung includes acquiring an MR image of the lung having MR data in a voxel and obtaining a breathing frequency parameter, determining a water density value, a specific ventilation value, and a perfusion value in at least one voxel of the MR image based on the MR data and using the water density value to determine an air content value, and determining a ventilation-perfusion ratio value that is the product of the specific ventilation value, the air content value, the inverse of the perfusion value, and the breathing frequency.

  4. Human versus Computer Controlled Selection of Ventilator Settings: An Evaluation of Adaptive Support Ventilation and Mid-Frequency Ventilation

    Directory of Open Access Journals (Sweden)

    Eduardo Mireles-Cabodevila

    2012-01-01

    Full Text Available Background. There are modes of mechanical ventilation that can select ventilator settings with computer controlled algorithms (targeting schemes. Two examples are adaptive support ventilation (ASV and mid-frequency ventilation (MFV. We studied how different clinician-chosen ventilator settings are from these computer algorithms under different scenarios. Methods. A survey of critical care clinicians provided reference ventilator settings for a 70 kg paralyzed patient in five clinical/physiological scenarios. The survey-derived values for minute ventilation and minute alveolar ventilation were used as goals for ASV and MFV, respectively. A lung simulator programmed with each scenario’s respiratory system characteristics was ventilated using the clinician, ASV, and MFV settings. Results. Tidal volumes ranged from 6.1 to 8.3 mL/kg for the clinician, 6.7 to 11.9 mL/kg for ASV, and 3.5 to 9.9 mL/kg for MFV. Inspiratory pressures were lower for ASV and MFV. Clinician-selected tidal volumes were similar to the ASV settings for all scenarios except for asthma, in which the tidal volumes were larger for ASV and MFV. MFV delivered the same alveolar minute ventilation with higher end expiratory and lower end inspiratory volumes. Conclusions. There are differences and similarities among initial ventilator settings selected by humans and computers for various clinical scenarios. The ventilation outcomes are the result of the lung physiological characteristics and their interaction with the targeting scheme.

  5. Effects of storage and yogurt matrix on the stability of tocotrienols encapsulated in chitosan-alginate microcapsules.

    Science.gov (United States)

    Tan, Phui Yee; Tan, Tai Boon; Chang, Hon Weng; Tey, Beng Ti; Chan, Eng Seng; Lai, Oi Ming; Baharin, Badlishah Sham; Nehdi, Imededdine Arbi; Tan, Chin Ping

    2018-02-15

    Tocotrienol microcapsules (TM) were formed by firstly preparing Pickering emulsion containing tocotrienols, which was then gelled into microcapsules using alginate and chitosan. In this study, we examined the stability of TM during storage and when applied into a model food system, i.e. yogurt. During storage at 40°C, TM displayed remarkably lower tocotrienols loss (50.8%) as compared to non-encapsulated tocotrienols in bulk oil (87.5%). When the tocotrienols were incorporated into yogurt, the TM and bulk oil forms showed a loss of 23.5% and 81.0%, respectively. Generally, the tocotrienols were stable in the TM form and showed highest stability when these TM were added into yogurt. δ-Tocotrienol was the most stable isomer in both forms during storage and when incorporated into yogurt. The addition of TM into yogurt caused minimal changes in the yogurt's color and texture but slightly altered the yogurt's viscosity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. A superconducting conveyer system using multiple bulk Y-Ba-Cu-O superconductors and permanent magnets

    Science.gov (United States)

    Kinoshita, T.; Koshizuka, N.; Nagashima, K.; Murakami, M.

    Developments of non-contact superconducting devices like superconducting magnetic levitation transfer and superconducting flywheel energy storage system have been performed based on the interactions between bulk Y-Ba-Cu-O superconductors and permanent magnets, in that the superconductors can stably be levitated without any active control. The performances of noncontact superconducting devices are dependent on the interaction forces like attractive forces and stiffness. In the present study, we constructed a non-contact conveyer for which the guide rails were prepared by attaching many Fe-Nd-B magnets onto an iron base plate. Along the translational direction, all the magnets were arranged as to face the same pole, and furthermore their inter-distance was made as small as possible. The guide rail has three magnet rows, for which the magnets were glued on the iron plate such that adjacent magnet rows have opposite poles like NSN. At the center row, the magnetic field at zero gap reached 0.61T, while the field strengths of two rows on the side edges were only 0.48T due to magnetic interactions among permanent magnets. We then prepared a cryogenic box made with FRP that can store several bulk Y-Ba-Cu-O superconductors 25 mm in diameter cooled by liquid nitrogen. It was found that the levitation forces and stiffness increased with increasing the number of bulk superconductors installed in the box, although the levitation force per unit bulk were almost the same. We also confirmed that these forces are dependent on the configuration of bulk superconductors.

  7. Ventilation models

    Science.gov (United States)

    Skaaret, Eimund

    Calculation procedures, used in the design of ventilating systems, which are especially suited for displacement ventilation in addition to linking it to mixing ventilation, are addressed. The two zone flow model is considered and the steady state and transient solutions are addressed. Different methods of supplying air are discussed, and different types of air flow are considered: piston flow, plane flow and radial flow. An evaluation model for ventilation systems is presented.

  8. Noninvasive ventilation.

    Science.gov (United States)

    Rabatin, J T; Gay, P C

    1999-08-01

    Noninvasive ventilation refers to the delivery of assisted ventilatory support without the use of an endotracheal tube. Noninvasive positive pressure ventilation (NPPV) can be delivered by using a volume-controlled ventilator, a pressure-controlled ventilator, a bilevel positive airway pressure ventilator, or a continuous positive airway pressure device. During the past decade, there has been a resurgence in the use of noninvasive ventilation, fueled by advances in technology and clinical trials evaluating its use. Several manufacturers produce portable devices that are simple to operate. This review describes the equipment, techniques, and complications associated with NPPV and also the indications for both short-term and long-term applications. NPPV clearly represents an important addition to the techniques available to manage patients with respiratory failure. Future clinical trials evaluating its many clinical applications will help to define populations of patients most apt to benefit from this type of treatment.

  9. Human response to ductless personalized ventilation coupled with displacement ventilation

    DEFF Research Database (Denmark)

    Dalewski, Mariusz; Veselý, Michal; Melikov, Arsen K.

    2012-01-01

    A human subject experiment was carried out to investigate the extent to which ductless personalized ventilation (DPV) in conjunction with displacement ventilation can improve perceived air quality (PAQ) and thermal comfort at elevated room air temperature in comparison with displacement ventilation...... alone. The experimental conditions comprised displacement ventilation alone (room air temperature of 23 °C, 26 °C, 29 °C) and DPV with displacement ventilation (26 °C, 29 °C), both operating at supply air temperatures 3, 5 or 6K lower than room air temperature, as well as mixing ventilation (23 °C, 3 K......). During one hour exposure participants answered questionnaires regarding PAQ and thermal comfort. PAQ was significantly better with DPV than without DPV at the same background conditions. Thermal comfort improved when DPV was used. Combining DPV with displacement ventilation showed the potential...

  10. Industrial ventilation

    Science.gov (United States)

    Goodfellow, H. D.

    Industrial ventilation design methodology, using computers and using fluid dynamic models, is considered. It is noted that the design of a ventilation system must be incorporated into the plant design and layout at the earliest conceptual stage of the project. A checklist of activities concerning the methodology for the design of a ventilation system for a new facility is given. A flow diagram of the computer ventilation model shows a typical input, the initialization and iteration loop, and the output. The application of the fluid dynamic modeling techniques include external and internal flow fields, and individual sources of heat and contaminants. Major activities for a ventilation field test program are also addressed.

  11. experimental characterization of the performances of a storage

    African Journals Online (AJOL)

    eobe

    STORAGE EXCHANGER WITH TUBE BANK AIR-PHASE CHANGE. PHASE CHANGE ... systems to transfer heat to the PCM during the day, and to evacuate its latent ... The use of the MVC. (Controlled Mechanical Ventilation) contributes to.

  12. Non-smoker exposure to secondhand cannabis smoke II: Effect of room ventilation on the physiological, subjective, and behavioral/cognitive effects.

    Science.gov (United States)

    Herrmann, Evan S; Cone, Edward J; Mitchell, John M; Bigelow, George E; LoDico, Charles; Flegel, Ron; Vandrey, Ryan

    2015-06-01

    Cannabis is the most widely used illicit drug. Many individuals are incidentally exposed to secondhand cannabis smoke, but little is known about the effects of this exposure. This report examines the physiological, subjective, and behavioral/cognitive effects of secondhand cannabis exposure, and the influence of room ventilation on these effects. Non-cannabis-using individuals were exposed to secondhand cannabis smoke from six individuals smoking cannabis (11.3% THC) ad libitum in a specially constructed chamber for 1h. Chamber ventilation was experimentally manipulated so that participants were exposed under unventilated conditions or with ventilation at a rate of 11 air exchanges/h. Physiological, subjective and behavioral/cognitive measures of cannabis exposure assessed after exposure sessions were compared to baseline measures. Exposure to secondhand cannabis smoke under unventilated conditions produced detectable cannabinoid levels in blood and urine, minor increases in heart rate, mild to moderate self-reported sedative drug effects, and impaired performance on the digit symbol substitution task (DSST). One urine specimen tested positive at using a 50 ng/ml cut-off and several specimens were positive at 20 ng/ml. Exposure under ventilated conditions resulted in much lower blood cannabinoid levels, and did not produce sedative drug effects, impairments in performance, or positive urine screen results. Room ventilation has a pronounced effect on exposure to secondhand cannabis smoke. Under extreme, unventilated conditions, secondhand cannabis smoke exposure can produce detectable levels of THC in blood and urine, minor physiological and subjective drug effects, and minor impairment on a task requiring psychomotor ability and working memory. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Hydrogen transport and storage in engineered glass microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Rambach, G.D.

    1994-04-20

    New, high-strength, hollow, glass microspheres filled with pressurized hydrogen exhibit storage densities which make them attractive for bulk hydrogen storage and transport. The hoop stress at failure of our engineered glass microspheres is about 150,000 psi, permitting a three-fold increase in pressure limit and storage capacity above commercial microspheres, which fail at wall stresses of 50,000 psi. For this project, microsphere material and structure will be optimized for storage capacity and charge/discharge kinetics to improve their commercial practicality. Microsphere production scale up will be performed, directed towards large-scale commercial use. Our analysis relating glass microspheres for hydrogen transport with infrastructure and economics` indicate that pressurized microspheres can be economically competitive with other forms of bulk rail and truck transport such as hydride beds, cryocarbons and pressurized tube transports. For microspheres made from advanced materials and processes, analysis will also be performed to identify the appropriate applications of the microspheres considering property variables, and different hydrogen infrastructure, end use, production and market scenarios. This report presents some of the recent modelling results for large beds of glass microspheres in hydrogen storage applications. It includes plans for experiments to identify the properties relevant to large-bed hydrogen transport and storage applications, of the best, currently producible, glass microspheres. This work began in March, 1994. Project successes will be manifest in the matching of cur-rent glass microspheres with a useful application in hydrogen bulk transport and storage, and in developing microsphere materials and processes that increase the storage density and reduce the storage energy requirement.

  14. Diffuse Ceiling Ventilation

    DEFF Research Database (Denmark)

    Zhang, Chen; Yu, Tao; Heiselberg, Per Kvols

    with conventional ventilation systems (mixing or displacement ventilation), diffuse ceiling ventilation can significantly reduce or even eliminate draught risk in the occupied zone. Moreover, this ventilation system presents a promising opportunity for energy saving, because of the low pressure loss, extended free...

  15. Diffuse ceiling ventilation

    DEFF Research Database (Denmark)

    Zhang, Chen

    Diffuse ceiling ventilation is an innovative ventilation concept where the suspended ceiling serves as air diffuser to supply fresh air into the room. Compared with conventional ventilation systems, diffuse ceiling ventilation can significantly reduce or even eliminate draught risk due to the low...

  16. Ventilation measured on clinical 4D-CBCT

    DEFF Research Database (Denmark)

    Rørdam Jensen, Kasper; Brink, Carsten; Hansen, Olfred

    2017-01-01

    as a gold standard the current study investigates if image improvements increase the accuracy of 4D-CBCT measured ventilation. MATERIAL AND METHODS: The study consists of 4D-CBCT and 4D-CT scans of 20 non-small-cell lung cancer patients. Raw CBCT projections were subjected to a standard or an improved...... and the SART reconstruction increased the accuracy of CBCT ventilation and this result can be a stepping stone to extract dynamic changes in respiration pattern of patients during radiotherapy....

  17. Characterization of spent fuel assemblies for storage facilities using non destructive assay

    International Nuclear Information System (INIS)

    Lebrun, A.; Bignan, G.; Recroix, H.; Huver, M.

    1999-01-01

    Many non destructive assay (NDA) techniques have been developed by the French Atomic Energy Commission (CEA) for spent fuel characterization and management. Passive and active neutron methods as well as gamma spectrometric methods have been carried out and applied to industrial devices like PYTHON TM and NAJA. Many existing NDA methods can be successfully applied to storage, but the most promising are the neutron methods combined with on line evolution codes. For dry storage applications, active neutron measurements require further R and D to achieve accurate results. Characterization data given by NDA instruments can now be linked to automatic fuel recognition. Both information can feed the storage management software in order to meet the storage operation requirements like: fissile mass inventory, operators declaration consistency or automatic selection of proper storage conditions. (author)

  18. Radioaerosol ventilation imaging in ventilator-dependent patients. Technical considerations

    International Nuclear Information System (INIS)

    Vezina, W.; Chamberlain, M.; Vinitski, S.; King, M.; Nicholson, R.; Morgan, W.K.

    1985-01-01

    The differentiation of pulmonary embolism (PE) from regional ventilatory abnormalities accompanied by reduced perfusion requires contemporary perfusion and ventilation studies. Distinguishing these conditions in ventilator-dependent patients is aided by administering a Tc-99m aerosol to characterize regional ventilation, and by performing a conventional Tc-99m MAA perfusion study. The technique uses a simple in-house constructed apparatus. Simple photographic techniques suffice, but computer subtraction of perfusion from the combined perfusion-ventilation image renders interpretation easier if aerosol administration follows perfusion imaging. Multiple defects can be examined in a single study. Excluding normal or near-normal perfusion studies, PE was thought to be present in eight of 16 patients after perfusion imaging alone, but in only one of eight after added aerosol imaging. Angiography confirmed the diagnosis in that patient. Of the eight patients who had abnormal perfusion but were thought unlikely to have PE from the perfusion study alone, two had normal ventilation, and subsequently were shown to have PE by angiography. Because angiography was only performed on patients who were thought to have a high probability of PE on sequential perfusion-ventilation imaging, the true incidence of PE may have been higher. Aerosol ventilation imaging is a useful adjunct to perfusion imaging in patients on ventilators. It requires an efficient delivery system, particularly if aerosol administration follows perfusion imaging, as it does in this study

  19. A Techno-Commercial Assessment of Residential and Bulk Battery Energy Storage

    Science.gov (United States)

    Nadkarni, Aditya

    2013-01-01

    Battery energy storage has shown a lot of potential in the recent past to be effective in various grid services due to its near instantaneous ramp rates and modularity. This thesis aims to determine the commercial viability of customer premises and substation sited battery energy storage systems. Five different types of services have been analyzed considering current market pricing of Lithium-ion batteries and power conditioning equipment. Energy Storage Valuation Tool 3.0 (Beta) has been used to exclusively determine the value of energy storage in the services analyzed. The results indicate that on the residential level, Lithium-ion battery energy storage may not be a cost beneficial option for retail tariff management or demand charge management as only 20-30% of the initial investment is recovered at the end of 15 year plant life. SRP's two retail Time-of-Use price plans E-21 and E-26 were analyzed in respect of their ability to increase returns from storage compared to those with flat pricing. It was observed that without a coupled PV component, E-21 was more suitable for customer premises energy storage, however, its revenue stream reduces with addition to PV. On the grid scale, however, with carefully chosen service hierarchy such as distribution investment deferral, spinning or balancing reserve support, the initial investment can be recovered to an extent of about 50-70%. The study done here is specific to Salt River Project inputs and data. Results for all the services analyzed are highly location specific and are only indicative of the overall viability and returns from them.

  20. Synchronized mechanical ventilation for respiratory support in newborn infants.

    Science.gov (United States)

    Greenough, Anne; Murthy, Vadivelam; Milner, Anthony D; Rossor, Thomas E; Sundaresan, Adesh

    2016-08-19

    /respiratory support dependency beyond 36 weeks' postmenstrual age (PMA) and duration of weaning/ventilation.Eight comparisons were made: (i) HFPPV versus CMV; (ii) ACV/SIMV versus CMV; (iii) SIMV or SIMV + PS versus HFO; iv) ACV versus SIMV; (v) SIMV plus PS versus SIMV; vi) SIMV versus PRVCV; vii) SIMV vs PSV; viii) ACV versus PSV. Data analysis was conducted using relative risk for categorical outcomes, mean difference for outcomes measured on a continuous scale. Twenty-two studies are included in this review. The meta-analysis demonstrates that HFPPV compared to CMV was associated with a reduction in the risk of air leak (typical relative risk (RR) for pneumothorax was 0.69, 95% confidence interval (CI) 0.51 to 0.93). ACV/SIMV compared to CMV was associated with a shorter duration of ventilation (mean difference (MD) -38.3 hours, 95% CI -53.90 to -22.69). SIMV or SIMV + PS was associated with a greater risk of moderate/severe BPD compared to HFO (RR 1.33, 95% CI 1.07 to 1.65) and a longer duration of mechanical ventilation compared to HFO (MD 1.89 days, 95% CI 1.04 to 2.74).ACV compared to SIMV was associated with a trend to a shorter duration of weaning (MD -42.38 hours, 95% CI -94.35 to 9.60). Neither HFPPV nor triggered ventilation was associated with a significant reduction in the incidence of BPD. There was a non-significant trend towards a lower mortality rate using HFPPV versus CMV and a non-significant trend towards a higher mortality rate using triggered ventilation versus CMV. No disadvantage of HFPPV or triggered ventilation was noted regarding other outcomes. Compared to conventional ventilation, benefit is demonstrated for both HFPPV and triggered ventilation with regard to a reduction in air leak and a shorter duration of ventilation, respectively. In none of the trials was complex respiratory monitoring undertaken and thus it is not possible to conclude that the mechanism of producing those benefits is by provocation of synchronised ventilation. Triggered

  1. USING POLYMERIC HYDROGEN GETTERS TO PREVENT COMBUSTIBLE ATMOSPHERES DURING INTERIM SAFE STORAGE OF PLUTONIUM OXIDE

    International Nuclear Information System (INIS)

    Woodsmall, T

    2007-01-01

    Nuclear Materials Management (NMM) of WSRC has recently installed the capability to perform both non-destructive and destructive examination of 3013 containers of Pu oxide in accordance with DOE-STD-3013. The containers will be opened and the oxide will be sampled for analysis. The remaining bulk oxide must then be safely stored in a non-3013-compliant configuration. Available processing equipment and controls cannot prevent the oxide from adsorbing moisture during this process. Subsequent radiolysis of moisture during storage may generate combustible quantities of gases while waiting final processing, and satisfying DOE Interim Safe Storage Criteria (ISSC) would require that storage containers be vented at impractical frequencies. With support from an independent National Laboratory, WSRC/NMM has demonstrated that a commercial hydrogen getter material will effectively prevent the accumulation of combustible gas concentrations. A project overview, including storage requirements and strategies, as well as getter technology, current test results, and anticipated future developments will be addressed

  2. Ventilation Model

    International Nuclear Information System (INIS)

    Yang, H.

    1999-01-01

    The purpose of this analysis and model report (AMR) for the Ventilation Model is to analyze the effects of pre-closure continuous ventilation in the Engineered Barrier System (EBS) emplacement drifts and provide heat removal data to support EBS design. It will also provide input data (initial conditions, and time varying boundary conditions) for the EBS post-closure performance assessment and the EBS Water Distribution and Removal Process Model. The objective of the analysis is to develop, describe, and apply calculation methods and models that can be used to predict thermal conditions within emplacement drifts under forced ventilation during the pre-closure period. The scope of this analysis includes: (1) Provide a general description of effects and heat transfer process of emplacement drift ventilation. (2) Develop a modeling approach to simulate the impacts of pre-closure ventilation on the thermal conditions in emplacement drifts. (3) Identify and document inputs to be used for modeling emplacement ventilation. (4) Perform calculations of temperatures and heat removal in the emplacement drift. (5) Address general considerations of the effect of water/moisture removal by ventilation on the repository thermal conditions. The numerical modeling in this document will be limited to heat-only modeling and calculations. Only a preliminary assessment of the heat/moisture ventilation effects and modeling method will be performed in this revision. Modeling of moisture effects on heat removal and emplacement drift temperature may be performed in the future

  3. How do changes in bulk soil organic carbon content affect carbon concentrations in individual soil particle fractions?

    Science.gov (United States)

    Yang, X. M.; Drury, C. F.; Reynolds, W. D.; Yang, J. Y.

    2016-06-01

    We test the common assumption that organic carbon (OC) storage occurs on sand-sized soil particles only after the OC storage capacity on silt- and clay-sized particles is saturated. Soil samples from a Brookston clay loam in Southwestern Ontario were analysed for the OC concentrations in bulk soil, and on the clay (<2 μm), silt (2-53 μm) and sand (53-2000 μm) particle size fractions. The OC concentrations in bulk soil ranged from 4.7 to 70.8 g C kg-1 soil. The OC concentrations on all three particle size fractions were significantly related to the OC concentration of bulk soil. However, OC concentration increased slowly toward an apparent maximum on silt and clay, but this maximum was far greater than the maximum predicted by established C sequestration models. In addition, significant increases in OC associated with sand occurred when the bulk soil OC concentration exceeded 30 g C kg-1, but this increase occurred when the OC concentration on silt + clay was still far below the predicted storage capacity for silt and clay fractions. Since the OC concentrations in all fractions of Brookston clay loam soil continued to increase with increasing C (bulk soil OC content) input, we concluded that the concept of OC storage capacity requires further investigation.

  4. Displacement Ventilation

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm

    Displacement ventilation is an interesting new type of air distribution principle which should be considered in connection with design of comfort ventilation in both smal1 and large spaces. Research activities on displacement ventilation are large all over the world and new knowledge of design...... methods appears continuously. This book gives an easy introduction to the basis of displacement ventilation and the chapters are written in the order which is used in a design procedure. The main text is extended by five appendices which show some of the new research activities taking place at Aalborg...

  5. Non-sedation versus sedation with a daily wake-up trial in critically ill patients recieving mechanical ventilation - effects on long-term cognitive function

    DEFF Research Database (Denmark)

    Nedergaard, Helene Korvenius; Jensen, Hanne Irene; Stylsvig, Mette

    2016-01-01

    trauma, status epilepticus, patients treated with therapeutic hypothermia and patients with severe hypoxia). The experimental intervention will be non-sedation supplemented with pain management during mechanical ventilation. The control intervention will be sedation with a daily wake-up attempt...

  6. Histochemical alterations in one lung ventilation.

    Science.gov (United States)

    Yin, Kingsley; Gribbin, Elizabeth; Emanuel, Steven; Orndorff, Rebecca; Walker, Jean; Weese, James; Fallahnejad, Manucher

    2007-01-01

    One lung ventilation is a commonly performed surgical procedure. Although there have been several reports showing that one-lung ventilation can cause pathophysiological alterations such as pulmonary hypoxic vasoconstriction and intrapulmonary shunting, there have been virtually no reports on the effects of one-lung ventilation on lung histology. Yorkshire pigs (11-17 kg) were anesthetized, a tracheotomy performed and a tracheal tube inserted. The chest was opened and one lung ventilation (OLV), was induced by clamping of the right main bronchus. OLV was continued for 60 min before the clamp was removed and two lung ventilation (TLV) started. TLV was continued for 30 to 60 min. Blood and lung biopsies were taken immediately before OLV, 30 min and 60 min of OLV and after restoration of TLV. Histological analyses revealed that the non-ventilated lung was totally collapsed during OLV. On reventilation, there was clear evidence of vascular congestion and alveolar wall thickening at 30 min after TLV. At 60 min of TLV, there was still vascular congestion. Serum nitrite levels (as an index of nitric oxide production) showed steady decline over the course of the experimental period, reaching a significantly low level on reventilation (compared with baseline levels before OLV). Lung MPO activity (marker of neutrophil sequestration) and serum TNFalpha levels were not raised during the entire experimental period. These results suggest that there was lung vascular injury after OLV, which was associated with reduced levels of nitric oxide production and not associated with an inflammatory response.

  7. Trigger performance of mid-level ICU mechanical ventilators during assisted ventilation: a bench study.

    Science.gov (United States)

    Ferreira, Juliana C; Chipman, Daniel W; Kacmarek, Robert M

    2008-09-01

    To compare the triggering performance of mid-level ICU mechanical ventilators with a standard ICU mechanical ventilator. Experimental bench study. The respiratory care laboratory of a university-affiliated teaching hospital. A computerized mechanical lung model, the IngMar ASL5000. Ten mid-level ICU ventilators were compared to an ICU ventilator at two levels of lung model effort, three combinations of respiratory mechanics (normal, COPD and ARDS) and two modes of ventilation, volume and pressure assist/control. A total of 12 conditions were compared. Performance varied widely among ventilators. Mean inspiratory trigger time was ventilators. The mean inspiratory delay time (time from initiation of the breath to return of airway pressure to baseline) was longer than that for the ICU ventilator for all tested ventilators except one. The pressure drop during triggering (Ptrig) was comparable with that of the ICU ventilator for only two ventilators. Expiratory Settling Time (time for pressure to return to baseline) had the greatest variability among ventilators. Triggering differences among these mid-level ICU ventilators and with the ICU ventilator were identified. Some of these ventilators had a much poorer triggering response with high inspiratory effort than the ICU ventilator. These ventilators do not perform as well as ICU ventilators in patients with high ventilatory demand.

  8. BULK THERMODYNAMICS AND CHARGE FLUCTUATIONS AT NON-VANISHING BARYON DENSITY

    International Nuclear Information System (INIS)

    MIAO, C.; SCHMIDT, C.

    2007-01-01

    We present results on bulk thermodynamic quantities as well as net baryon number, strangeness and electric charge fluctuations in QCD at non-zero density and temperature obtained from lattice calculations with almost physical quark masses for two values of the lattice cut-off aT = 1/4 and 1/6. We show that with our improved p4fa3-action the cut-off effects are under control when using lattices with a temporal extent of 6 or larger and that the contribution to the equation of state, which is due to a finite chemical potential is small for μ q /T < 1. Moreover, at vanishing chemical potential, i.e. under conditions almost realized at RHIC and the LHC, quartic fluctuations of net baryon number and strangeness are large in a narrow temperature interval characterizing the transition region from the low to high temperature phase. At non-zero baryon number density, strangeness fluctuations are enhanced and correlated to fluctuations of the net baryon number. If strangeness is furthermore forced to vanish, as it may be the case in systems created in heavy ion collisions, strangeness fluctuations are significantly smaller than baryon number fluctuations

  9. Modes of mechanical ventilation for the operating room.

    Science.gov (United States)

    Ball, Lorenzo; Dameri, Maddalena; Pelosi, Paolo

    2015-09-01

    Most patients undergoing surgical procedures need to be mechanically ventilated, because of the impact of several drugs administered at induction and during maintenance of general anaesthesia on respiratory function. Optimization of intraoperative mechanical ventilation can reduce the incidence of post-operative pulmonary complications and improve the patient's outcome. Preoxygenation at induction of general anaesthesia prolongs the time window for safe intubation, reducing the risk of hypoxia and overweighs the potential risk of reabsorption atelectasis. Non-invasive positive pressure ventilation delivered through different interfaces should be considered at the induction of anaesthesia morbidly obese patients. Anaesthesia ventilators are becoming increasingly sophisticated, integrating many functions that were once exclusive to intensive care. Modern anaesthesia machines provide high performances in delivering the desired volumes and pressures accurately and precisely, including assisted ventilation modes. Therefore, the physicians should be familiar with the potential and pitfalls of the most commonly used intraoperative ventilation modes: volume-controlled, pressure-controlled, dual-controlled and assisted ventilation. Although there is no clear evidence to support the advantage of any one of these ventilation modes over the others, protective mechanical ventilation with low tidal volume and low levels of positive end-expiratory pressure (PEEP) should be considered in patients undergoing surgery. The target tidal volume should be calculated based on the predicted or ideal body weight rather than on the actual body weight. To optimize ventilation monitoring, anaesthesia machines should include end-inspiratory and end-expiratory pause as well as flow-volume loop curves. The routine administration of high PEEP levels should be avoided, as this may lead to haemodynamic impairment and fluid overload. Higher PEEP might be considered during surgery longer than 3 h

  10. Volume-Targeted Ventilation in the Neonate: Benchmarking Ventilators on an Active Lung Model.

    Science.gov (United States)

    Krieger, Tobias J; Wald, Martin

    2017-03-01

    Mechanically ventilated neonates have been observed to receive substantially different ventilation after switching ventilator models, despite identical ventilator settings. This study aims at establishing the range of output variability among 10 neonatal ventilators under various breathing conditions. Relative benchmarking test of 10 neonatal ventilators on an active neonatal lung model. Neonatal ICU. Ten current neonatal ventilators. Ventilators were set identically to flow-triggered, synchronized, volume-targeted, pressure-controlled, continuous mandatory ventilation and connected to a neonatal lung model. The latter was configured to simulate three patients (500, 1,500, and 3,500 g) in three breathing modes each (passive breathing, constant active breathing, and variable active breathing). Averaged across all weight conditions, the included ventilators delivered between 86% and 110% of the target tidal volume in the passive mode, between 88% and 126% during constant active breathing, and between 86% and 120% under variable active breathing. The largest relative deviation occurred during the 500 g constant active condition, where the highest output machine produced 147% of the tidal volume of the lowest output machine. All machines deviate significantly in volume output and ventilation regulation. These differences depend on ventilation type, respiratory force, and patient behavior, preventing the creation of a simple conversion table between ventilator models. Universal neonatal tidal volume targets for mechanical ventilation cannot be transferred from one ventilator to another without considering necessary adjustments.

  11. Operational experience at RCD and FCD laboratories during various ventilation conditions

    International Nuclear Information System (INIS)

    Murali, S.; Ashok Kumar, P.; Thanamani, M.; Rath, D.P.; Sapkal, J.A.; Raman, Anand

    2007-01-01

    Radiochemistry and Fuel Chemistry wing of Radiological Laboratory facility has various radio-chemical operations on isotopes of plutonium and trans-plutonium elements, carried out under containment and safe operational conditions. The ventilation provided to the facility is a Once - through system. The ventilation system is designed with separate headers for laboratory and glove box exhausts. There is scheduled periodic shut down of ventilation system for maintenance during non-occupancy hours/week ends. The buildup of natural α - emitters activity due to ventilation shut down, observed to be prevailing on stack air sample filter papers after the ventilation startup, is studied. The paper describes the operational experience gained over a period during ventilation shut down and suggests the course of remedial action for reducing the internal exposure due to build up of natural α - emitters and their progenies. (author)

  12. Pilot scale facility to determine gaseous emissions from livestock slurry during storage

    DEFF Research Database (Denmark)

    Petersen, Søren O; Skov, Morten; Drøscher, Per

    2009-01-01

    Livestock production is a growing source of air pollution, locally and to the wider environment. Improved livestock manure management has the potential to reduce environmental impacts, but there is a need for methodologies to precisely quantify emissions. This paper describes and evaluates a novel...... storage facility for livestock slurry consisting of eight 6.5-m3 cylindrical units. The stores may be equipped with airtight covers and ventilated during storage or during measurement only. Each store has eight air inlets (160 mm diameter) and a single outlet in the cover connected to a main ventilation...... duct. The stores can also be used as static enclosures. Ventilation can be regulated within the range of 50 to 250 m3 h-1 A gas sampling line enables sampling of odorants using automatic thermal desorption tubes, ammonia using acid traps, and greenhouse gases using gas sampling bags (pooled samples...

  13. Enhanced deep ocean ventilation and oxygenation with global warming

    Science.gov (United States)

    Froelicher, T. L.; Jaccard, S.; Dunne, J. P.; Paynter, D.; Gruber, N.

    2014-12-01

    Twenty-first century coupled climate model simulations, observations from the recent past, and theoretical arguments suggest a consistent trend towards warmer ocean temperatures and fresher polar surface oceans in response to increased radiative forcing resulting in increased upper ocean stratification and reduced ventilation and oxygenation of the deep ocean. Paleo-proxy records of the warming at the end of the last ice age, however, suggests a different outcome, namely a better ventilated and oxygenated deep ocean with global warming. Here we use a four thousand year global warming simulation from a comprehensive Earth System Model (GFDL ESM2M) to show that this conundrum is a consequence of different rates of warming and that the deep ocean is actually better ventilated and oxygenated in a future warmer equilibrated climate consistent with paleo-proxy records. The enhanced deep ocean ventilation in the Southern Ocean occurs in spite of increased positive surface buoyancy fluxes and a constancy of the Southern Hemisphere westerly winds - circumstances that would otherwise be expected to lead to a reduction in deep ocean ventilation. This ventilation recovery occurs through a global scale interaction of the Atlantic Meridional Overturning Circulation undergoing a multi-centennial recovery after an initial century of transient decrease and transports salinity-rich waters inform the subtropical surface ocean to the Southern Ocean interior on multi-century timescales. The subsequent upwelling of salinity-rich waters in the Southern Ocean strips away the freshwater cap that maintains vertical stability and increases open ocean convection and the formation of Antarctic Bottom Waters. As a result, the global ocean oxygen content and the nutrient supply from the deep ocean to the surface are higher in a warmer ocean. The implications for past and future changes in ocean heat and carbon storage will be discussed.

  14. Multi-Fluid Geo-Energy Systems for Bulk and Thermal Energy Storage and Dispatchable Renewable and Low-Carbon Electricity

    Science.gov (United States)

    Buscheck, T. A.; Randolph, J.; Saar, M. O.; Hao, Y.; Sun, Y.; Bielicki, J. M.

    2014-12-01

    Integrating renewable energy sources into electricity grids requires advances in bulk and thermal energy storage technologies, which are currently expensive and have limited capacity. We present an approach that uses the huge fluid and thermal storage capacity of the subsurface to harvest, store, and dispatch energy from subsurface (geothermal) and surface (solar, nuclear, fossil) thermal resources. CO2 captured from fossil-energy systems and N2 separated from air are injected into permeable formations to store pressure, generate artesian flow of brine, and provide additional working fluids. These enable efficient fluid recirculation, heat extraction, and power conversion, while adding operational flexibility. Our approach can also store and dispatch thermal energy, which can be used to levelize concentrating solar power and mitigate variability of wind and solar power. This may allow low-carbon, base-load power to operate at full capacity, with the stored excess energy being available to addresss diurnal and seasonal mismatches between supply and demand. Concentric rings of horizontal injection and production wells are used to create a hydraulic divide to store pressure, CO2, N2, and thermal energy. Such storage can take excess power from the grid and excess thermal energy, and dispatch that energy when it is demanded. The system is pressurized and/or heated when power supply exceeds demand and depressurized when demand exceeds supply. Supercritical CO2 and N2 function as cushion gases to provide enormous pressure-storage capacity. Injecting CO2 and N2 displaces large quantities of brine, reducing the use of fresh water. Geologic CO2 storage is a crucial option for reducing CO2 emissions, but valuable uses for CO2 are needed to justify capture costs. The initial "charging" of our system requires permanently isolating large volumes of CO2 from the atmosphere and thus creates a market for its disposal. Our approach is designed for locations where a permeable

  15. VENTILATION NEEDS DURING CONSTRUCTION

    International Nuclear Information System (INIS)

    C.R. Gorrell

    1998-01-01

    The purpose of this analysis is to determine ventilation needs during construction and development of the subsurface repository and develop systems to satisfy those needs. For this analysis, construction is defined as pre-emplacement excavation and development is excavation that takes place simultaneously with emplacement. The three options presented in the ''Overall Development and Emplacement Ventilation Systems'' analysis (Reference 5.5) for development ventilation will be applied to construction ventilation in this analysis as well as adding new and updated ventilation factors to each option for both construction and development. The objective of this analysis is to develop a preferred ventilation system to support License Application Design. The scope of this analysis includes: (1) Description of ventilation conditions; (2) Ventilation factors (fire hazards, dust control, construction logistics, and monitoring and control systems); (3) Local ventilation alternatives; (4) Global ventilation options; and (5) Evaluation of options

  16. Ventilative Cooling

    DEFF Research Database (Denmark)

    Heiselberg, Per Kvols; Kolokotroni, Maria

    This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state-of-the-art of ventil......This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state......-of-the-art of ventilative cooling potentials and limitations, its consideration in current energy performance regulations, available building components and control strategies and analysis methods and tools. In addition, the report provides twenty six examples of operational buildings using ventilative cooling ranging from...

  17. Non-aqueous energy storage devices using graphene nanosheets synthesized by green route

    Directory of Open Access Journals (Sweden)

    Dattakumar Mhamane

    2013-04-01

    Full Text Available In this paper we report the use of triethylene glycol reduced graphene oxide (TRGO as an electrode material for non-aqueous energy storage devices such as supercapacitors and Li-ion batteries. TRGO based non–aqueous symmetric supercapacitor is constructed and shown to deliver maximum energy and power densities of 60.4 Wh kg–1 and 0.15 kW kg–1, respectively. More importantly, symmetric supercapacitor shows an extraordinary cycleability (5000 cycles with over 80% of capacitance retention. In addition, Li-storage properties of TRGO are also evaluated in half-cell configuration (Li/TRGO and shown to deliver a reversible capacity of ∼705 mAh g–1 with good cycleability at constant current density of 37 mA g–1. This result clearly suggests that green-synthesized graphene can be effectively used as a prospective electrode material for non-aqueous energy storage systems such as Li-ion batteries and supercapacitors.

  18. Conservative fluid management prevents age-associated ventilator induced mortality.

    Science.gov (United States)

    Herbert, Joseph A; Valentine, Michael S; Saravanan, Nivi; Schneck, Matthew B; Pidaparti, Ramana; Fowler, Alpha A; Reynolds, Angela M; Heise, Rebecca L

    2016-08-01

    Approximately 800 thousand patients require mechanical ventilation in the United States annually with an in-hospital mortality rate of over 30%. The majority of patients requiring mechanical ventilation are over the age of 65 and advanced age is known to increase the severity of ventilator-induced lung injury (VILI) and in-hospital mortality rates. However, the mechanisms which predispose aging ventilator patients to increased mortality rates are not fully understood. Ventilation with conservative fluid management decreases mortality rates in acute respiratory distress patients, but to date there has been no investigation of the effect of conservative fluid management on VILI and ventilator associated mortality rates. We hypothesized that age-associated increases in susceptibility and incidence of pulmonary edema strongly promote age-related increases in ventilator associated mortality. 2month old and 20month old male C57BL6 mice were mechanically ventilated with either high tidal volume (HVT) or low tidal volume (LVT) for up to 4h with either liberal or conservative fluid support. During ventilation, lung compliance, total lung capacity, and hysteresis curves were quantified. Following ventilation, bronchoalveolar lavage fluid was analyzed for total protein content and inflammatory cell infiltration. Wet to dry ratios were used to directly measure edema in excised lungs. Lung histology was performed to quantify alveolar barrier damage/destruction. Age matched non-ventilated mice were used as controls. At 4h, both advanced age and HVT ventilation significantly increased markers of inflammation and injury, degraded pulmonary mechanics, and decreased survival rates. Conservative fluid support significantly diminished pulmonary edema and improved pulmonary mechanics by 1h in advanced age HVT subjects. In 4h ventilations, conservative fluid support significantly diminished pulmonary edema, improved lung mechanics, and resulted in significantly lower mortality rates in

  19. Effects of non-invasive ventilation on objective sleep and nocturnal respiration in patients with amyotrophic lateral sclerosis.

    Science.gov (United States)

    Boentert, Matthias; Brenscheidt, Inga; Glatz, Christian; Young, Peter

    2015-09-01

    In amyotrophic lateral sclerosis (ALS), non-invasive ventilation (NIV) is indicated if sleep-disordered breathing (SDB), daytime hypercapnia, or significant diaphragmatic weakness is present. We investigated both short-term and long-term effects of NIV on objective measures of sleep and nocturnal respiration in patients with ALS. Polysomnography (PSG) and transcutaneous capnography were conducted for diagnosis of SDB (T0), for treatment initiation (T1), and follow-up 3, 9, and 15 months later (T2, T3, and T4, respectively). Records from 65 patients were retrospectively analyzed at T0 and T1. At subsequent timepoints, the number of full data sets decreased since follow-up sleep studies frequently included polygraphy rather than PSG (T2, 38 patients, T3, 17 patients, T4, 11 patients). At T0, mean age was 63.2 years, 29 patients were female, and 22 patients had bulbar ALS. Immediate sequelae of NIV initiation included significant increases of slow wave sleep, rapid eye movement sleep, and oxygen saturation. Mean apnea-hypopnea index, respiratory rate, and the maximum transcutaneous carbon dioxide tension were reduced. At T2-T4, normoxia and normocapnia were preserved. Sleep quality measures showed no alteration as diurnal use of NIV gradually increased reflecting disease progression. In contrast to previous reports, improvement of sleep and respiratory outcomes was found in both non-bulbar and bulbar patients. NIV significantly improves objective sleep quality and SDB in the first night of treatment in patients with bulbar and non-bulbar ALS. NIV warrants nocturnal normoventilation without deterioration of sleep quality in the long run with only minor changes to ventilator settings.

  20. Mask Ventilation during Induction of General Anesthesia: Influences of Obstructive Sleep Apnea.

    Science.gov (United States)

    Sato, Shin; Hasegawa, Makoto; Okuyama, Megumi; Okazaki, Junko; Kitamura, Yuji; Sato, Yumi; Ishikawa, Teruhiko; Sato, Yasunori; Isono, Shiroh

    2017-01-01

    Depending on upper airway patency during anesthesia induction, tidal volume achieved by mask ventilation may vary. In 80 adult patients undergoing general anesthesia, the authors tested a hypothesis that tidal volume during mask ventilation is smaller in patients with sleep-disordered breathing priorly defined as apnea hypopnea index greater than 5 per hour. One-hand mask ventilation with a constant ventilator setting (pressure-controlled ventilation) was started 20 s after injection of rocuronium and maintained for 1 min during anesthesia induction. Mask ventilation efficiency was assessed by the breath number needed to initially exceed 5 ml/kg ideal body weight of expiratory tidal volume (primary outcome) and tidal volumes (secondary outcomes) during initial 15 breaths (UMIN000012494). Tidal volume progressively increased by more than 70% in 1 min and did not differ between sleep-disordered breathing (n = 42) and non-sleep-disordered breathing (n = 38) patients. In post hoc subgroup analyses, the primary outcome breath number (mean [95% CI], 5.7 [4.1 to 7.3] vs. 1.7 [0.2 to 3.2] breath; P = 0.001) and mean tidal volume (6.5 [4.6 to 8.3] vs. 9.6 [7.7 to 11.4] ml/kg ideal body weight; P = 0.032) were significantly smaller in 20 sleep-disordered breathing patients with higher apnea hypopnea index (median [25th to 75th percentile]: 21.7 [17.6 to 31] per hour) than in 20 non-sleep disordered breathing subjects with lower apnea hypopnea index (1.0 [0.3 to 1.5] per hour). Obesity and occurrence of expiratory flow limitation during one-hand mask ventilation independently explained the reduction of efficiency of mask ventilation, while the use of two hands effectively normalized inefficient mask ventilation during one-hand mask ventilation. One-hand mask ventilation is difficult in patients with obesity and severe sleep-disordered breathing particularly when expiratory flow limitation occurs during mask ventilation.

  1. Use of non-invasive ventilation is increasing in patients admitted with a chronic obstructive pulmonary disease exacerbation

    DEFF Research Database (Denmark)

    Tøttenborg, Sandra Søgaard; Johnsen, Søren Paaske; Thomsen, Reimar Wernich

    2013-01-01

    INTRODUCTION: A nationwide chronic obstructive pulmonary disease (COPD) quality improvement programme - DrCOPD - was initiated in Denmark in 2008. We examined subsequent national and regional trends in the use of non-invasive ventilation (NIV) and trends in mortality following NIV and invasive...... the launch of a national COPD quality programme in 2008. However, regional variation remains and no substantial improvements in mortality have been observed. Continued efforts are warranted to ensure appropriate implementation of NIV. FUNDING: The study was supported financially by University of Copenhagen...

  2. [Prospective evaluation on ventilator-associated events: a cohort study from eight intensive care units].

    Science.gov (United States)

    Chen, W S; Liu, J; Liu, H; Song, Y Y; Chen, H Y; Wang, R; Zhang, Y P; Jiang, W; Li, H F; Li, S Q; Zhang, S M; Liu, B; Zhang, X; Zhang, W H

    2016-08-10

    The aim of this study was to prospectively investigate the incidence of ventilator associated events (VAEs) in intensive care units (ICUs) among adult patients, and to evaluate the correlation between VAEs and ventilator associated pneumonia (VAP). A prospective 3-month cohort study (January 2015 to March 2015) was carried out. VAEs were divided into three groups: with ventilator-associated condition (VAC), with infection related ventilator-associated complication (IVAC) and with possible VAP (PVAP). Sensitivity and specificity of VAEs were evaluated and compared to the traditional VAP. Kappa test was applied to judge the consistency of VAC and VAP. During Jan. 2015 and Mar. 2015, 1 014 patients were admitted to 8 ICUs, with 7 977 patients per day. In total, 197 patients used the mechanical ventilation installation, with, a total number of 3 152 ventilator-days. Finally, 1 214 ventilation days in the VAC group and 1 938 ventilation days in the non-VAC group) that were available for final analysis. 46 VAC cases were identified including 22 classified as IVAC (14.59 and 6.98 per 1 000 ventilation days, respectively). Length of ICU stay and duration on mechanical ventilation for VAC patients were both significantly longer than those for non-VAC patients (PVAC criteria for the detection of VAP were 36.92% and 83.33%, respectively. The VAEs surveillance paradigms could be applied to monitor patients on the use of mechanical ventilation installation. However, sensitivity and specificity of VAC were under pool for the diagnosis of VAP. However, automatically surveillance programs was relied on the improvement of auto-information systems.

  3. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Power ventilation systems except machinery space ventilation systems. 111.103-1 Section 111.103-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Power ventilation systems except machinery space ventilation systems. Each power ventilation system must...

  4. Optimal allocation of energy storage in a co-optimized electricity market: Benefits assessment and deriving indicators for economic storage ventures

    International Nuclear Information System (INIS)

    Krishnan, Venkat; Das, Trishna

    2015-01-01

    This paper presents a framework for optimally allocating storage technologies in a power system. This decision support tool helps in quantitatively answering the questions on “where to and how much to install” considering the profits from arbitrage opportunities in a co-optimized electricity market. The developed framework is illustrated on a modified IEEE (Institute of Electrical and Electronics Engineers) 24 bus RTS (Reliability Test System), and the framework finds the optimal allocation solution and the revenues storage earns at each of these locations. Bulk energy storage, CAES (compressed air energy storage) is used as the representative storage technology, and the benefits of optimally allocated storage integration onto the grid are compared with transmission expansion solution. The paper also discusses about system-level indicators to identify candidate locations for economical storage ventures, which are derived based on the optimal storage allocation solution; and applies the market price based storage venture indicators on MISO (Mid-continental Independent System Operator) and PJM (Pennsylvania-New Jersey-Maryland Interconnection) electricity markets. - Highlights: • Storage optimal allocation framework based on high-fidelity storage dispatch model. • Storage with transmission addresses energy and ancillary issues under high renewables. • Bulk storage earns higher revenues from co-optimization (∼10× energy only market). • Grid offers distributed opportunities for investing in a strategic mix of storage. • Storage opportunities depend on cross-arbitrage, as seen from MISO (Mid-continental Independent System Operator) and PJM (Pennsylvania-New Jersey-Maryland Interconnection) markets

  5. [Pressure support ventilation and proportional assist ventilation during weaning from mechanical ventilation].

    Science.gov (United States)

    Aguirre-Bermeo, H; Bottiroli, M; Italiano, S; Roche-Campo, F; Santos, J A; Alonso, M; Mancebo, J

    2014-01-01

    To compare tolerance, duration of mechanical ventilation (MV) and clinical outcomes during weaning from MV in patients subjected to either pressure support ventilation (PSV) or proportional assist ventilation (PAV). A prospective, observational study was carried out. Intensive Care Unit. A total of 40 consecutive subjects were allocated to either the PSV or the PAV group until each group contained 20 patients. Patients were included in the study when they met the criteria to begin weaning and the attending physician decided to initiate the weaning process. The physician selected the modality and set the ventilatory parameters. None. Demographic data, respiratory mechanics, ventilatory parameters, duration of MV, and clinical outcomes (reintubation, tracheostomy, mortality). Baseline characteristics were similar in both groups. No significant differences were observed between the PSV and PAV groups in terms of the total duration of MV (10 [5-18] vs. 9 [7-19] days; P=.85), reintubation (5 [31%] vs. 3 [19%]; P=.69), or mortality (4 [20%] vs. 5 [25%] deaths; P=1). Eight patients (40%) in the PSV group and 6 patients (30%) in the PAV group (P=.74) required a return to volume assist-control ventilation due to clinical deterioration. Tolerance, duration of MV and clinical outcomes during weaning from mechanical ventilation were similar in PSV and PAV. Copyright © 2013 Elsevier España, S.L. and SEMICYUC. All rights reserved.

  6. Nursing workload and adherence to non-pharmacological measures in the prevention of ventilator-associated pneumonia. A pilot study.

    Science.gov (United States)

    Jam, R; Hernández, O; Mesquida, J; Turégano, C; Carrillo, E; Pedragosa, R; Gómez, V; Martí, L; Vallés, J; Delgado-Hito, P

    To analyse whether adherence to non-pharmacological measures in the prevention of ventilator-associated pneumonia (VAP) is associated with nursing workload. A prospective observational study performed in a single medical-surgical ICU. Nurses in charge of patients under ventilator support were assessed. knowledge questionnaire, application of non-pharmacological VAP prevention measures, and workload (Nine Equivalents of Nursing Manpower Use Score). Phases: 1) the nurses carried out a educational programme, consisting of 60-minute lectures on non-pharmacological measures for VAP prevention, and at the end completed a questionnaire knowledge; 2) observation period; 3) knowledge questionnaire. Among 67 ICU-staff nurses, 54 completed the educational programme and were observed. A total of 160 observations of 49 nurses were made. Adequate knowledge was confirmed in both the initial and final questionnaires. Application of preventive measures ranged from 11% for hand washing pre-aspiration to 97% for the use of a sterile aspiration probe. The Nine Equivalents of Nursing Manpower Use Score was 50±13. No significant differences were observed between the association of the nurses' knowledge and the application of preventive measures or between workload and the application of preventive measures. Nurses' knowledge of VAP prevention measures is not necessarily applied in daily practice. Failure to follow these measures is not subject to lack of knowledge or to increased workload, but presumably to contextual factors. Copyright © 2017 Sociedad Española de Enfermería Intensiva y Unidades Coronarias (SEEIUC). Publicado por Elsevier España, S.L.U. All rights reserved.

  7. Spent fuel heatup following loss of water during storage

    International Nuclear Information System (INIS)

    Benjamin, A.S.; McCloskey, D.J.; Powers, D.A.; Dupree, S.A.

    1979-03-01

    An analysis of spent fuel heatup following a hypothetical accident involving drainage of the storage pool is presented. Computations based upon a new computer code called SFUEL have been performed to assess the effect of decay time, fuel element design, storage rack design, packing density, room ventilation, drainage level, and other variables on the heatup characteristics of the spent fuel and to predict the conditions under which clad failure will occur. Possible storage pool design modifications and/or onsite emergency action have also been considered

  8. Ventilation effectiveness

    CERN Document Server

    Mathisen, Hans Martin; Nielsen, Peter V; Moser, Alfred

    2004-01-01

    Improving the ventilation effectiveness allows the indoor air quality to be significantly enhanced without the need for higher air changes in the building, thereby avoiding the higher costs and energy consumption associated with increasing the ventilation rates. This Guidebook provides easy-to-understand descriptions of the indices used to mesure the performance of a ventilation system and which indices to use in different cases.

  9. RedVent. Turned off ventilation at night in schools - risks and opportunities; RedVent. Avstaengd ventilation paa natten i skolor - risker och moejligheter

    Energy Technology Data Exchange (ETDEWEB)

    Haegerhed Engman, Linda; Fyhr, Kristina; Langer, Sarka; Ruud, Svein; Ylmen, Peter

    2011-07-01

    Reduced ventilation rates or shutdown ventilation during nights is often being used in school buildings in order to save energy and can decrease the energy cost for heating and ventilation with at least 30 %. Swedish Building Regulations (BBR) allows reduced ventilation flow in non-residential buildings when no one is using the building but it must not give rise to adverse health effects or damage the building or its installations. Potential risks are mould- and moisture damages and indoor air quality problems. Another question is whether the shut down itself might lead to indoor air quality problems due to chemical reactions between outdoor air and indoor emissions built-up during the night. The study was divided into three steps; an interview with property managers and care-taker, calculations of energy saving potentials and a field study. Measurements were per-formed in one classroom for two weeks in April 2010. Different set-ups for ventilation flow during night time and air tightness of the building envelope were studied; ventilation shut down, intermittent ventilation (15 min every second hour) and continuous full speed ventilation during night. In the studied classroom, shutdown ventilation during nights did not significantly affect the indoor air quality in the classroom during the school day even though there were effects seen during the night. We found a somewhat higher moisture accumulation those nights when the ventilation was shut down and some fractions of particles during intermittent ventilation compared to continues full ventilation during night time. This specific school and classroom were well ventilated and there was no moisture supply from new building material or other types of moisture producing activities. Schools with lower day-time ventilation rates, moisture in building construction, IAQ- or dampness problems as well as buildings close to heavy traffic should analyse the conditions for the specific building before reducing ventilation to

  10. Systematic review of non-invasive positive pressure ventilation for chronic respiratory failure.

    Science.gov (United States)

    Hannan, Liam M; Dominelli, Giulio S; Chen, Yi-Wen; Darlene Reid, W; Road, Jeremy

    2014-02-01

    This systematic review examined the effect of non-invasive positive pressure ventilation (NIPPV) on patient reported outcomes (PROs) and survival for individuals with or at risk of chronic respiratory failure (CRF). Randomised controlled trials (RCTs) and prospective non-randomised studies in those treated with NIPPV for CRF were identified from electronic databases, reference lists and grey literature. Diagnostic groups included in the review were amyotrophic lateral sclerosis/motor neuron disease (ALS/MND), Duchenne muscular dystrophy (DMD), restrictive thoracic disease (RTD) and obesity hypoventilation syndrome (OHS). Eighteen studies were included and overall study quality was weak. Those with ALS/MND had improved somnolence and fatigue as well as prolonged survival with NIPPV. For OHS, improvements in somnolence and fatigue, dyspnoea and sleep quality were demonstrated, while for RTD, measures of dyspnoea, sleep quality, physical function and health, mental and emotional health and social function improved. There was insufficient evidence to form conclusions regarding the effect of NIPPV for those with DMD. This review has demonstrated that NIPPV influences PROs differently depending on the underlying cause of CRF. These findings may provide assistance to patients and clinicians to determine the relative costs and benefits of NIPPV therapy and also highlight areas in need of further research. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Protective lung ventilation in operating room: a systematic review.

    Science.gov (United States)

    Futier, E; Constantin, J M; Jaber, S

    2014-06-01

    Postoperative pulmonary and extrapulmonary complications adversely affect clinical outcomes and healthcare utilization, so that prevention has become a measure of the quality of perioperative care. Mechanical ventilation is an essential support therapy to maintain adequate gas exchange during general anesthesia for surgery. Mechanical ventilation using high tidal volume (VT) (between 10 and 15 mL/kg) has been historically encouraged to prevent hypoxemia and atelectasis formation in anesthetized patients undergoing abdominal and thoracic surgery. However, there is accumulating evidence from both experimental and clinical studies that mechanical ventilation, especially the use of high VT and plateau pressure, may potentially aggravate or even initiate lung injury. Ventilator-associated lung injury can result from cyclic alveolar overdistension of non-dependent lung tissue, and repetitive opening and closing of dependent lung tissue resulting in ultrastructural damage at the junction of closed and open alveoli. Lung-protective ventilation, which refers to the use of lower VT and limited plateau pressure to minimize overdistension, and positive end-expiratory pressure to prevent alveolar collapse at end-expiration, was shown to improve outcome in critically ill patients with acute respiratory distress syndrome (ARDS). It has been recently suggested that this approach might also be beneficial in a broader population, especially in critically ill patients without ARDS at the onset of mechanical ventilation. There is, however, little evidence regarding a potential beneficial effect of lung protective ventilation during surgery, especially in patients with healthy lungs. Although surgical patients are frequently exposed to much shorter periods of mechanical ventilation, this is an important gap in knowledge given the number of patients receiving mechanical ventilation in the operating room. This review developed the benefits of lung protective ventilation during surgery

  12. EVALUATION OF BEST AVAILABLE CONTROL TECHNOLOGY FOR TOXICS (TBACT) DOUBLE SHELL TANK FARMS PRIMARY VENTILATION SYSTEM SUPPORTING WASTE TRANSFER OPERATIONS

    International Nuclear Information System (INIS)

    Kelly, S.E.; Haass, C.C.; Kovach, J.L.; Turner, D.A.

    2010-01-01

    This report is an evaluation of Best Available Control Technology for Toxics (tBACT) for installation and operation of the Hanford double shell (DST) tank primary ventilation systems. The DST primary ventilation systems are being modified to support Hanford's waste retrieval, mixing, and delivery of single shell tank (SST) and DST waste through out the DST storage system to the Waste Treatment and Immobilization Plant (WTP).

  13. EVALUATION OF BEST AVAILABLE CONTROL TECHNOLOGY FOR TOXICS (TBACT) DOUBLE SHELL TANK FARMS PRIMARY VENTILATION SYSTEMS SUPPORTING WASTE TRANSFER OPERATIONS

    International Nuclear Information System (INIS)

    Haas, C.C.; Kovach, J.L.; Kelly, S.E.; Turner, D.A.

    2010-01-01

    This report is an evaluation of Best Available Control Technology for Toxics (tBACT) for installation and operation of the Hanford double shell (DST) tank primary ventilation systems. The DST primary ventilation systems are being modified to support Hanford's waste retrieval, mixing, and delivery of single shell tank (SST) and DST waste through the DST storage system to the Waste Treatment and Immobilization Plant (WTP).

  14. EVALUATION OF BEST AVAILABLE CONTROL TECHNOLOGY FOR TOXICS (TBACT) DOUBLE SHELL TANK FARMS PRIMARY VENTILATION SYSTEM SUPPORTING WASTE TRANSFER OPERATIONS

    Energy Technology Data Exchange (ETDEWEB)

    KELLY SE; HAASS CC; KOVACH JL; TURNER DA

    2010-06-03

    This report is an evaluation of Best Available Control Technology for Toxics (tBACT) for installation and operation of the Hanford double shell (DST) tank primary ventilation systems. The DST primary ventilation systems are being modified to support Hanford's waste retrieval, mixing, and delivery of single shell tank (SST) and DST waste throught the DST storage system to the Waste Treatment and Immobilization Plant (WTP).

  15. EVALUATION OF BEST AVAILABLE CONTROL TECHNOLOGY FOR TOXICS -TBACT- DOUBLE SHELL TANK FARMS PRIMARY VENTILATION SYSTEMS SUPPORTING WASTE TRANSFER OPERATIONS

    Energy Technology Data Exchange (ETDEWEB)

    HAAS CC; KOVACH JL; KELLY SE; TURNER DA

    2010-06-24

    This report is an evaluation of Best Available Control Technology for Toxics (tBACT) for installation and operation of the Hanford double shell (DST) tank primary ventilation systems. The DST primary ventilation systems are being modified to support Hanford's waste retrieval, mixing, and delivery of single shell tank (SST) and DST waste through the DST storage system to the Waste Treatment and Immobilizaiton Plant (WTP).

  16. Intra-Hospital Transport of Patients on Non-Invasive Ventilation: Review, Analysis, and Key Practical Recommendations by the International NIV Committee

    Directory of Open Access Journals (Sweden)

    Annia Schreiber

    2017-12-01

    Full Text Available Intra-hospital transport is often needed for diagnostic and therapeutic procedures that cannot be performed at the bedside. However, moving patients from the safe environment of an Intensive Care Unit (ICU can lead to a variety of complications and adverse events, the risk is even higher in ventilated patients. This review is intended as a guide on how to prevent and avoid these adverse events during intra-hospital transport of patients on non-invasive ventilation (NIV. Greater attention should be paid to NIV indications and the selection of the patients to be transported. Detailed planning, preparation, and communication between the ward of origin and destination site, appropriate equipment, skilled staff, and continuous monitoring are the key major determinants of success in transporting critically ill patients on NIV. These points are discussed and analyzed in detail.

  17. A new type of rapid and simple coal and other bulk commodities inventory system based on two-dimensional laser scanner

    Science.gov (United States)

    Liang, Qianqian; Xu, Wenhai; Ma, Qisheng; Yang, Deshan; Zhang, Wang; Fu, Ying

    2016-10-01

    The acceleration of large coal base construction needs the modern management technology of heap storage as a guarantee. And the inventory of coal and other bulk commodities is an important aspect in the modern management technology of heap storage. Therefore, a rapid, accurate and simple method to measure the volume and quality of coal heaps for scientific management, economic benefit evaluation and storage evaluation of heap storage is very important which has a significant application value. In this paper, we introduce the structural features, working principle and application status of a new type portable heap bulk inventory system. Actual measurements have been carried out in the coal base located in Huanghua port, Tianjin and Qinhuangdao. The measurement results indicate that the system can measure the volume of bulk commodities efficiently, quickly and accurately, and it has extensive application prospects.

  18. Home telemonitoring of non-invasive ventilation decreases healthcare utilisation in a prospective controlled trial of patients with amyotrophic lateral sclerosis.

    Science.gov (United States)

    Pinto, Anabela; Almeida, José Pedro; Pinto, Susana; Pereira, João; Oliveira, António Gouveia; de Carvalho, Mamede

    2010-11-01

    Non-invasive ventilation (NIV) is an efficient method for treating respiratory failure in patients with amyotrophic lateral sclerosis (ALS). However, it requires a process of adaptation not always achieved due to poor compliance. The role of telemonitoring of NIV is not yet established. To test the advantage of using modem communication in NIV of ALS patients. Prospective, single blinded controlled trial. Population and methods According to their residence, 40 consecutive ventilated ALS patients were assigned to one of two groups: a control group (G1, n=20) in which compliance and ventilator parameter settings were assessed during office visits; or an intervention group (G2, n=20) in which patients received a modem device connected to the ventilator. The number of office and emergency room visits and hospital admissions during the entire span of NIV use and the number of parameter setting changes to achieve full compliance were the primary outcome measurements. Demographic and clinical features were similar between the two groups at admission. No difference in compliance was found between the groups. The incidence of changes in parameter settings throughout the survival period with NIV was lower in G2 (p<0.0001) but it was increased during the initial period needed to achieve full compliance. The number of office or emergency room visits and inhospital admissions was significantly lower in G2 (p<0.0001). Survival showed a trend favouring G2 (p=0.13). This study shows that telemonitoring reduces health care utilisation with probable favourable implications on costs, survival and functional status.

  19. The effect of entrainment site and inspiratory pressure on the delivery of oxygen therapy during non-invasive mechanical ventilation (NIMV in acute COPD patients

    Directory of Open Access Journals (Sweden)

    Sundeep Kaul

    2006-12-01

    Full Text Available Supplemental O2 is frequently added to bi-level non-invasive ventilation circuits to maintain Sa,O2 >90%. Oxygen can be added at several points & in the presence of different inspiratory pressures. The effect of varying entrainment sites and inspiratory pressures (IPAP on PO2, PCO2, Fio2, inspiratory triggering and expiratory triggering in COPD patients is unknown. 18 patients with stable COPD (mean FEV1 47% participated in the study. Oxygen was added at 4 sites in the ventilatory circuit (site 1: between mask and exhalation port; site 2: just distal to exhalation port; site 3: at ventilator outlet; site 4: directly into the mask via an inlet. The effect of varying entrainment sites and inspiratory pressures on arterial PO2, PCO2, FIO2, was recorded at 3 mins. The same full face mask (Respironics, Image 3 & ventilator (Respironics, BIPAP ST 30 was used.

  20. Investigation of four-dimensional computed tomography-based pulmonary ventilation imaging in patients with emphysematous lung regions

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Tokihiro; Loo, Billy W Jr; Keall, Paul J [Department of Radiation Oncology, Stanford University School of Medicine, 875 Blake Wilbur Dr, Stanford, CA 94305-5847 (United States); Kabus, Sven; Lorenz, Cristian; Von Berg, Jens; Blaffert, Thomas [Department of Digital Imaging, Philips Research Europe, Roentgenstrasse 24-26, D-22335 Hamburg (Germany); Klinder, Tobias, E-mail: Tokihiro@stanford.edu [Clinical Informatics, Interventional, and Translational Solutions, Philips Research North America, Briarcliff Manor, NY 10510 (United States)

    2011-04-07

    A pulmonary ventilation imaging technique based on four-dimensional (4D) computed tomography (CT) has advantages over existing techniques. However, physiologically accurate 4D-CT ventilation imaging has not been achieved in patients. The purpose of this study was to evaluate 4D-CT ventilation imaging by correlating ventilation with emphysema. Emphysematous lung regions are less ventilated and can be used as surrogates for low ventilation. We tested the hypothesis: 4D-CT ventilation in emphysematous lung regions is significantly lower than in non-emphysematous regions. Four-dimensional CT ventilation images were created for 12 patients with emphysematous lung regions as observed on CT, using a total of four combinations of two deformable image registration (DIR) algorithms: surface-based (DIR{sup sur}) and volumetric (DIR{sup vol}), and two metrics: Hounsfield unit (HU) change (V{sub HU}) and Jacobian determinant of deformation (V{sub Jac}), yielding four ventilation image sets per patient. Emphysematous lung regions were detected by density masking. We tested our hypothesis using the one-tailed t-test. Visually, different DIR algorithms and metrics yielded spatially variant 4D-CT ventilation images. The mean ventilation values in emphysematous lung regions were consistently lower than in non-emphysematous regions for all the combinations of DIR algorithms and metrics. V{sub HU} resulted in statistically significant differences for both DIR{sup sur} (0.14 {+-} 0.14 versus 0.29 {+-} 0.16, p = 0.01) and DIR{sup vol} (0.13 {+-} 0.13 versus 0.27 {+-} 0.15, p < 0.01). However, V{sub Jac} resulted in non-significant differences for both DIR{sup sur} (0.15 {+-} 0.07 versus 0.17 {+-} 0.08, p = 0.20) and DIR{sup vol} (0.17 {+-} 0.08 versus 0.19 {+-} 0.09, p = 0.30). This study demonstrated the strong correlation between the HU-based 4D-CT ventilation and emphysema, which indicates the potential for HU-based 4D-CT ventilation imaging to achieve high physiologic accuracy. A

  1. Effect Of Ventilation On Chronic Health Risks In Schools And Offices

    Energy Technology Data Exchange (ETDEWEB)

    Parthasarathy, Srinandini [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); McKone, Thomas E. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-01-04

    This study provides a risk assessment for chronic health risks from inhalation exposure to indoor air pollutants in offices and schools with a focus how ventilation impacts exposures to, and risks from, volatile organic compounds (VOCs) and particulate matter (PM2.5). We estimate how much health risks could change with varying ventilation rates under two scenarios: (i) halving the measured ventilation rates and (ii) doubling the measured ventilation rates. For the hazard characterization we draw upon prior papers that identified pollutants potentially affecting health with indoor air concentrations responsive to changes in ventilation rates. For exposure assessment we determine representative concentrations of pollutants using data available in current literature and model changes in exposures with changes in ventilation rates. As a metric of disease burden, we use disability adjusted life years (DALYs) to address both cancer and non-cancer effects. We also compare exposures to guidelines published by regulatory agencies to assess chronic health risks. Chronic health risks are driven primarily by particulate matter exposure, with an estimated baseline disease burden of 150 DALYs per 100,000 people in offices and 140 DALYs per 100,000 people in schools. Study results show that PM2.5-related DALYs are not very sensitive to changes in ventilation rates. Filtration is more effective at controlling PM2.5 concentrations and health effects. Non-cancer health effects contribute only a small fraction of the overall chronic health burden of populations in offices and schools (<1 DALY per 100,000 people). Cancer health effects dominate the disease burden in schools (3 DALYs per 100,000) and offices (5 DALYs per 100,000), with formaldehyde being the primary risk driver. In spite of large uncertainties in toxicological data and dose-response modeling, our results support the finding that ventilation rate changes do not have significant impacts on estimated chronic disease

  2. First-principles study of hydrogen storage in non-stoichiometric TiCx

    International Nuclear Information System (INIS)

    Ding, Haimin; Fan, Xiaoliang; Li, Chunyan; Liu, Xiangfa; Jiang, Dong; Wang, Chunyang

    2013-01-01

    Highlights: ► The absorption of hydrogen in non-stoichiometric TiC x is thermally favorable. ► As many as four hydrogen atoms can be trapped by a carbon vacancy. ► The diffusion of hydrogen in TiC x is difficult, especially in TiC x with high x. - Abstract: In this work, the first principles calculation has been performed to study the hydrogen storage in non-stoichiometric TiC x . It is found that hydrogen absorption in stoichiometric TiC is energetically unfavorable, while it is favorable in non-stoichiometric TiC x . This indicates that the existence of carbon vacancies is essential for hydrogenation storage in TiC x . At the same time, multiple hydrogen occupancy of the vacancy has been confirmed and it is calculated that as many as four hydrogen atoms can be trapped by a carbon vacancy. These absorbed hydrogen atoms tend to uniformly distribute around the vacancy. However, it is also found that the diffusion of hydrogen atoms in TiC x is difficult, especially in TiC x with high x.

  3. Trial of ventilation assistance unit for administration of Technegas

    International Nuclear Information System (INIS)

    Croft, E.; McLaren, C.; Campbell, L.; Pennington, C.; Crelin, D.

    1997-01-01

    Full text: The current method used for administration of Technegas relies on patient co-operation. It requires patient compliance with breathing instructions. Administration of Technegas in non-compliant patients, for example the unconscious/ventilated patient, is very difficult. Images are frequently sub-optimal and may be impossible to achieve. In an effort to overcome these difficulties we have been trialing a prototype ventilation assistance unit (VAU). The unit comprises a light and portable attachment to the standard Technegas machine. It utilises a hand viva bag and actively forces Technegas into the patient. Two people are required to perform the ventilation. It is our experience that the VAU greatly improves the likelihood of successful administration of Technegas in these patients, and may have application in conscious patients who would be difficult to ventilate in the usual manner for a variety of reasons (e.g. tracheotomy, extreme SOB and the very elderly). Using the VAU we have increased confidence in performing ventilation studies in the more difficult patients. Our early experience will be presented along with suggestions for utilisation of the VAU

  4. Nasal mask ventilation is better than face mask ventilation in edentulous patients.

    Science.gov (United States)

    Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

    2016-01-01

    Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively evaluated. After induction of anesthesia and administration of neuromuscular blocker, lungs were ventilated with a standard anatomical face mask of appropriate size, using a volume controlled anesthesia ventilator with tidal volume set at 10 ml/kg. In case of inadequate ventilation, the mask position was adjusted to achieve best-fit. Inspired and expired tidal volumes were measured. Thereafter, the face mask was replaced by a nasal mask and after achieving best-fit, the inspired and expired tidal volumes were recorded. The difference in expired tidal volumes and airway pressures at best-fit with the use of the two masks and number of patients with inadequate ventilation with use of the masks were statistically analyzed. A total of 79 edentulous patients were recruited for the study. The difference in expiratory tidal volumes with the use of the two masks at best-fit was statistically significant (P = 0.0017). Despite the best-fit mask placement, adequacy of ventilation could not be achieved in 24.1% patients during face mask ventilation, and 12.7% patients during nasal mask ventilation and the difference was statistically significant. Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients.

  5. A Stratification Boomerang: Nonlinear Dependence of Deep Southern Ocean Ventilation on PCO2

    Science.gov (United States)

    Galbraith, E. D.; Merlis, T. M.

    2014-12-01

    Strong correlations between atmospheric CO2, Antarctic temperatures, and marine proxy records have hinted that ventilation of the deep Southern Ocean may have played a central role in the variations of CO2 over glacial-interglacial cycles. One proposition is that, in general, the Southern Ocean ventilates the deep more strongly under higher CO2, due to a change in winds and/or the dominance of thermal stratification in a warm ocean, which weakens ocean biological carbon storage. Here, we explore this idea with a suite of multi-millennial simulations using the GFDL CM2Mc global coupled model. The results are, indeed, consistent with increasing ventilation of the Southern Ocean as pCO2 increases above modern. However, they reveal a surprising twist under low pCO2: increased salinity of the Southern Ocean, due in part to weakening atmospheric moisture transport, actually increases ventilation rate of the deep ocean under low pCO2 as well. This implies that a nadir of Southern Ocean ventilation occurs at intermediate pCO2, which the model estimates as being close to that of the present-day. This is at odds with the interpretation that weak ventilation of the deep Southern Ocean was the unifying coupled mechanism for the glacial pCO2 cycles. Rather, it suggests that factors other than the ventilation rate of the deep Southern Ocean, such as iron fertilization, ecosystem changes, water mass distributions, and sea ice cover, were key players in the glacial-interglacial CO2 changes.

  6. Non-invasive ventilation used as an adjunct to airway clearance treatments improves lung function during an acute exacerbation of cystic fibrosis: a randomised trial

    Directory of Open Access Journals (Sweden)

    Tiffany J Dwyer

    2015-07-01

    Full Text Available Question: During an acute exacerbation of cystic fibrosis, is non-invasive ventilation beneficial as an adjunct to the airway clearance regimen? Design: Randomised controlled trial with concealed allocation and intention-to-treat analysis. Participants: Forty adults with moderate to severe cystic fibrosis lung disease and who were admitted to hospital for an acute exacerbation. Intervention: Comprehensive inpatient care (control group compared to the same care with the addition of non-invasive ventilation during airway clearance treatments from Day 2 of admission until discharge (experimental group. Outcome measures: Lung function and subjective symptom severity were measured daily. Fatigue was measured at admission and discharge on the Schwartz Fatigue Scale from 7 (no fatigue to 63 (worst fatigue points. Quality of life and exercise capacity were also measured at admission and discharge. Length of admission and time to next hospital admission were recorded. Results: Analysed as the primary outcome, the experimental group had a greater rate of improvement in forced expiratory volume in 1 second (FEV1 than the control group, but this was not statistically significant (MD 0.13% predicted per day, 95% CI –0.03 to 0.28. However, the experimental group had a significantly higher FEV1 at discharge than the control group (MD 4.2% predicted, 95% CI 0.1 to 8.3. The experimental group reported significantly lower levels of fatigue on the Schwartz fatigue scale at discharge than the control group (MD 6 points, 95% CI 1 to 11. There was no significant difference between the experimental and control groups in subjective symptom severity, quality of life, exercise capacity, length of hospital admission or time to next hospital admission. Conclusion: Among people hospitalised for an acute exacerbation of cystic fibrosis, the use of non-invasive ventilation as an adjunct to the airway clearance regimen significantly improves FEV1 and fatigue. Trial

  7. SUPRAGLOTTIC JET VENTILATION VERSUS CONVENTIONAL ENDOTRACHEAL VENTILATION IN MINOR LARYNGEAL SURGERIES

    Directory of Open Access Journals (Sweden)

    Illendual Upendranath

    2016-08-01

    Full Text Available Any attempt at intubation will cause many cardiovascular responses and the major concern during this time is to attenuate the same. Similar response is seen during procedures on Larynx in microlaryngeal surgery which produces an intense cardiovascular stimulation during suspension laryngoscopy and intubation. AIM OF STUDY Supraglottic jet ventilation versus conventional endotracheal ventilation in minor laryngeal surgeries. To evaluate the haemodynamic response in supraglottic jet ventilation and conventional intubation in minor laryngeal surgeries. METHODS Patients were randomised to 2 Groups: 30 patients in each group; Group A - in whom supraglottic jet ventilation was planned and Group B - in whom endotracheal intubation was planned. RESULT The haemodynamic response in terms of increase in MAP and HR is significantly more with endotracheal intubation than with supraglottic jet ventilation. CONCLUSION Our study showed that supraglottic jet ventilation showed a better haemodynamic stability when compared to conventional endotracheal intubation in patients undergoing minor laryngeal surgeries. Statistical scores were also in favour of the patients treated with supraglottic jet ventilation based on the p values.

  8. Storage and handling of willow from short rotation coppice

    Energy Technology Data Exchange (ETDEWEB)

    Kofman, P. D.; Spinelli, R.

    1997-07-01

    During the project two main storage and drying trials were organised. The first trial in 1996 consisted of 14 piles of 6 different size material (whole shoots, via 200 mm chunk, 100 mm chunk, 50 mm chip, 28 mm chips, 25 mm chips) and six different methods of covering: Open air storage, storage under plastic cover, storage under top-cover, airtight storage, unventilated storage under roof, and intermittent ventilation (cooling) under roof. The drying trial in 1997 which consisted of four piles was established in Horsens in the same building as the ventilated trials the year before. Only Austoft 50 mm chips were used for this trial. The four piles were established in February and removed in May. Based on all the results of the trials the following conclusions can be drawn: Storage of willow from short rotation coppice is very difficult. Fine chips, such as producted by the two main harvesting machines Claas and Austoft are not suitable for storage over prolonged periods of time (more than 2 months); fine chips loose a large amount of dry matter and a lot of their lower heating value; fine chips also have a heavy infestation of micro-organisms which might cause working environment problems; short rotation coppice is best delivered straight into the heating plants during harvest; if short rotation coppice has to be stored, then this should be done as whole shoots or large chunk; if short rotation coppice has to be stored as chips for a longer period of time (more than two months), then these chips should be sealed airtight as silage. (EG) EFP-94; EFP-95; EFP-96. 10 refs.

  9. History of Mechanical Ventilation. From Vesalius to Ventilator-induced Lung Injury.

    Science.gov (United States)

    Slutsky, Arthur S

    2015-05-15

    Mechanical ventilation is a life-saving therapy that catalyzed the development of modern intensive care units. The origins of modern mechanical ventilation can be traced back about five centuries to the seminal work of Andreas Vesalius. This article is a short history of mechanical ventilation, tracing its origins over the centuries to the present day. One of the great advances in ventilatory support over the past few decades has been the development of lung-protective ventilatory strategies, based on our understanding of the iatrogenic consequences of mechanical ventilation such as ventilator-induced lung injury. These strategies have markedly improved clinical outcomes in patients with respiratory failure.

  10. Ventilation system type, classroom environmental quality and pupils' perceptions and symptoms

    DEFF Research Database (Denmark)

    Gao, Jie; Wargocki, Pawel; Wang, Yi

    2014-01-01

    The present study investigated indoor climate and window opening behaviour by pupils, as well as their perceptions and symptoms in classrooms with different types of ventilation systems. Four classrooms were selected in the same school in suburban Denmark. Classroom ventilation was achieved either......-heating and heating seasons; CO2 concentration was used to estimate average classroom ventilation rates. At the end of each measuring period, the pupils were asked to report their perceptions of the indoor environment and their acute health-related symptoms. The classroom in which ventilation was achieved by manually...... operable windows had the highest air temperatures and CO2 concentrations during both non-heating and heating season; the estimated average air-change rate was lowest in this classroom. The classroom with mechanical ventilation had the highest estimated average air-change rate. Windows were frequently...

  11. Modeling geologic storage of carbon dioxide: Comparison of non-hysteretic and hysteretic characteristic curves

    International Nuclear Information System (INIS)

    Doughty, Christine

    2007-01-01

    Numerical models of geologic storage of carbon dioxide (CO 2 ) in brine-bearing formations use characteristic curves to represent the interactions of non-wetting-phase CO 2 and wetting-phase brine. When a problem includes both injection of CO 2 (a drainage process) and its subsequent post-injection evolution (a combination of drainage and wetting), hysteretic characteristic curves are required to correctly capture the behavior of the CO 2 plume. In the hysteretic formulation, capillary pressure and relative permeability depend not only on the current grid-block saturation, but also on the history of the saturation in the grid block. For a problem that involves only drainage or only wetting, a non-hysteretic formulation, in which capillary pressure and relative permeability depend only on the current value of the grid-block saturation, is adequate. For the hysteretic formulation to be robust computationally, care must be taken to ensure the differentiability of the characteristic curves both within and beyond the turning-point saturations where transitions between branches of the curves occur. Two example problems involving geologic CO 2 storage are simulated with TOUGH2, a multiphase, multicomponent code for flow and transport through geological media. Both non-hysteretic and hysteretic formulations are used, to illustrate the applicability and limitations of non-hysteretic methods. The first application considers leakage of CO 2 from the storage formation to the ground surface, while the second examines the role of heterogeneity within the storage formation

  12. Effect of storage conditions on the calorific value of municipal solid waste.

    Science.gov (United States)

    Nzioka, Antony Mutua; Hwang, Hyeon-Uk; Kim, Myung-Gyun; Yan, Cao Zheng; Lee, Chang-Soo; Kim, Young-Ju

    2017-08-01

    Storage conditions are considered to be an important factor as far as waste material characteristics are concerned. This experimental investigation was conducted using municipal solid waste (MSW) with a high moisture content and varying composition of organic waste. The objective of this study was to understand the effect of storage conditions and temperature on the moisture content and calorific value of the waste. Samples were subjected to two different storage conditions and investigated at specified temperatures. The composition of sample materials investigated was varied for each storage condition and temperature respectively. Gross calorific value was determined experimentally while net calorific value was calculated using empirical formulas proposed by other researchers. Results showed minimal changes in moisture content as well as in gross and net calorific values when the samples were subjected to sealed storage conditions. Moisture content reduced due to the ventilation process and the rate of moisture removal increased with a rise in storage temperature. As expected, rate of moisture removal had a positive effect on gross and net calorific values. Net calorific values also increased at varying rates with a simultaneous decrease in moisture content. Experimental investigation showed the effectiveness of ventilation in improving the combustion characteristics of the waste.

  13. Advanced design of local ventilation systems

    Energy Technology Data Exchange (ETDEWEB)

    Kulmala, I. [VTT Manufacturing Technology, Espoo (Finland). Safety Technology

    1997-12-31

    Local ventilation is widely used in industry for controlling airborne contaminants. However, the present design practices of local ventilation systems are mainly based on empirical equations and do not take quantitatively into account the various factors affecting the performance of these systems. The aim of this study was to determine the applicability and limitations of more advanced fluid mechanical methods to the design and development of local ventilation systems. The most important factors affecting the performance of local ventilation systems were determined and their effect was studied in a systematic manner. The numerical calculations were made with the FLUENT computer code and they were verified by laboratory experiments, previous measurements or analytical solutions. The results proved that the numerical calculations can provide a realistic simulation of exhaust openings, effects of ambient air flows and wake regions. The experiences with the low-velocity local supply air showed that these systems can also be modelled fairly well. The results were used to improve the efficiency and thermal comfort of a local ventilation unit and to increase the effective control range of exhaust hoods. In the simulation of the interaction of a hot buoyant source and local exhaust, the predicted capture efficiencies were clearly higher than those observed experimentally. The deviations between measurements and non-isothermal flow calculations may have partly been caused by the inability to achieve grid independent solutions. CFD simulations is an advanced and flexible tool for designing and developing local ventilation. The simulations can provide insight into the time-averaged flow field which may assist us in understanding the observed phenomena and to explain experimental results. However, for successful calculations the applicability and limitations of the models must be known. (orig.) 78 refs.

  14. Essays on Port, Container, and Bulk Chemical Logistics Optimization

    NARCIS (Netherlands)

    E. van Asperen (Eelco)

    2009-01-01

    textabstractThe essays in this thesis are concerned with two main themes in port logistics. The first theme is the coordination of transport arrivals with the distribution processes and the use of storage facilities. We study this for both containerized and bulk chemical transport. The second theme

  15. The Challenging Diagnosis of Non-Community-Acquired Pneumonia in Non-Mechanically Ventilated Subjects: Value of Microbiological Investigation.

    Science.gov (United States)

    Messika, Jonathan; Stoclin, Annabelle; Bouvard, Eric; Fulgencio, Jean-Pierre; Ridel, Christophe; Muresan, Ioan-Paul; Boffa, Jean-Jacques; Bachmeyer, Claude; Denis, Michel; Gounant, Valérie; Esteso, Adoracion; Loi, Valeria; Verdet, Charlotte; Prigent, Hélène; Parrot, Antoine; Fartoukh, Muriel

    2016-02-01

    Early recognition and an attempt at obtaining microbiological documentation are recommended in patients with non-community-acquired pneumonia (NCAP), whether hospital-acquired (HAP) or health care-associated (HCAP). We aimed to characterize the clinical features and microbial etiologies of NCAP to assess the impact of microbiological investigation on their management. This was a prospective 1-y study in a university hospital with 141 non-mechanically ventilated subjects suspected of having HAP (n = 110) or HCAP (n = 31). Clinical criteria alone poorly identified pneumonia (misdiagnosis in 50% of cases). Microbiological confirmation was achievable in 80 subjects (57%). Among 79 microorganisms isolated, 28 were multidrug-resistant aerobic Gram-negative bacilli and group III Enterobacteriaceae and 6 were methicillin-resistant Staphylococcus aureus. Multidrug-resistant aerobic Gram-negative bacilli accounted for one third of the microorganisms in early-onset HAP and for 50% in late-onset HAP. Methicillin-resistant S. aureus was most often recovered from subjects with HCAP. Inappropriate empirical antibiotics were administered to 36% of subjects with confirmed pneumonia. Forty subjects were admitted to the ICU, 13 (33%) of whom died. Overall, 39 subjects (28%) died in the hospital. Integrating the microbiological investigation in the complex clinical diagnostic workup of patients suspected of having NCAP is mandatory. Respiratory tract specimens should be obtained whenever possible for appropriate management. Copyright © 2016 by Daedalus Enterprises.

  16. Physico-mechanical characteristics of commercially available bulk-fill composites.

    Science.gov (United States)

    Leprince, Julian G; Palin, William M; Vanacker, Julie; Sabbagh, Joseph; Devaux, Jacques; Leloup, Gaetane

    2014-08-01

    Bulk-fill composites have emerged, arguably, as a new "class" of resin-based composites, which are claimed to enable restoration in thick layers, up to 4mm. The objective of this work was to compare, under optimal curing conditions, the physico-mechanical properties of most currently available bulk-fill composites to those of two conventional composite materials chosen as references, one highly filled and one flowable "nano-hybrid" composite. Tetric EvoCeram Bulk Fill (Ivoclar-Vivadent), Venus Bulk Fill (Heraeus-Kulzer), SDR (Dentsply), X-tra Fil (VOCO), X-tra Base (VOCO), Sonic Fill (Kerr), Filtek Bulk Fill (3M-Espe), Xenius (GC) were compared to the two reference materials. The materials were light-cured for 40s in a 2mm×2mm×25mm Teflon mould. Degree of conversion was measured by Raman spectroscopy, Elastic modulus and flexural strength were evaluated by three point bending, surface hardness using Vickers microindentation before and after 24h ethanol storage, and filler weight content by thermogravimetric analysis. The ratio of surface hardness before and after ethanol storage was considered as an evaluation of polymer softening. Data were analyzed by one-way ANOVA and post hoc Tukey's test (p=0.05). The mechanical properties of the bulk-fill composites were mostly lower compared with the conventional high viscosity material, and, at best, comparable to the conventional flowable composite. Linear correlations of the mechanical properties investigated were poor with degree of conversion (0.090.8). Softening in ethanol revealed differences in polymer network density between material types. The reduction of time and improvement of convenience associated with bulk-fill materials is a clear advantage of this particular material class. However, a compromise with mechanical properties compared with more conventional commercially-available nano-hybrid materials was demonstrated by the present work. Given the lower mechanical properties of most bulk-fill materials

  17. Non-invasive ventilation in acute respiratory failure in children.

    Science.gov (United States)

    Abadesso, Clara; Nunes, Pedro; Silvestre, Catarina; Matias, Ester; Loureiro, Helena; Almeida, Helena

    2012-04-02

    The aim of this paper is to assess the clinical efficacy of non-invasive ventilation (NIV) in avoiding endotracheal intubation (ETI), to demonstrate clinical and gasometric improvement and to identify predictive risk factors associated with NIV failure. An observational prospective clinical study was carried out. Included Patients with acute respiratory disease (ARD) treated with NIV, from November 2006 to January 2010 in a Pediatric Intensive Care Unit (PICU). NIV was used in 151 patients with acute respiratory failure (ARF). Patients were divided in two groups: NIV success and NIV failure, if ETI was required. Mean age was 7.2±20.3 months (median: 1 min: 0,3 max.: 156). Main diagnoses were bronchiolitis in 102 (67.5%), and pneumonia in 44 (29%) patients. There was a significant improvement in respiratory rate (RR), heart rate (HR), pH, and pCO(2) at 2, 6, 12 and 24 hours after NIV onset (Papneia (P<0.001; odds ratio 15.8; 95% confidence interval: 3.42-71.4) and pneumonia (P<0.001, odds ratio 31.25; 95% confidence interval: 8.33-111.11). There were no major complications related with NIV. In conclusion this study demonstrates the efficacy of NIV as a form of respiratory support for children and infants with ARF, preventing clinical deterioration and avoiding ETI in most of the patients. Risk factors for failure were related with immaturity and severe infection.

  18. Gravity-dependent ventilation distribution in rats measured with electrical impedance tomography

    International Nuclear Information System (INIS)

    Rooney, Daniel; Fraser, John F; R Dunster, Kimble; Schibler, Andreas; Friese, Marlies

    2009-01-01

    Ventilation in larger animals and humans is gravity dependent and mainly distributed to the dependent lung. Little is known of the effect of gravity on ventilation distribution in small animals such as rodents. The aim of this study was to investigate gravity-dependent ventilation distribution and regional filling characteristics in rats. Ventilation distribution and regional lung filling were measured in six rats using electrical impedance tomography (EIT). Measurements were performed in four body positions (supine, prone, left and right lateral), and all animals were ventilated with increasing tidal volumes from 3 to 8 mL kg −1 . The effect of gravity on regional ventilation distribution was assessed with profiles of relative impedance change and calculation of the geometric centre. Regional filling was measured by calculating the slope of the plot of regional versus global relative impedance change on a breath-by-breath basis. Ventilation was significantly distributed to the non-dependent lung regardless of body position and tidal volume used. The geometric centre was located in the dependent lung in all but prone position. The regional filling characteristics followed an anatomical pattern with the posterior and the right lung generally filling faster. Gravity had little impact on regional filling. Ventilation distribution in rats is gravity dependent, whereas regional filling characteristics are dependent on anatomy

  19. Water spray ventilator system for continuous mining machines

    Science.gov (United States)

    Page, Steven J.; Mal, Thomas

    1995-01-01

    The invention relates to a water spray ventilator system mounted on a continuous mining machine to streamline airflow and provide effective face ventilation of both respirable dust and methane in underground coal mines. This system has two side spray nozzles mounted one on each side of the mining machine and six spray nozzles disposed on a manifold mounted to the underside of the machine boom. The six spray nozzles are angularly and laterally oriented on the manifold so as to provide non-overlapping spray patterns along the length of the cutter drum.

  20. Development of technology to utilize existing tobacco kilns and/or tobacco storage barns for curing (drying) and/or storage of other crops

    Energy Technology Data Exchange (ETDEWEB)

    VanHooren, D L; Scott, J J

    1988-01-01

    This report investigates methods to utilize existing bulk tobacco kilns for curing (drying) of shelled corn, peanuts, and baled hay. In recent years Ontario tobacco producers have had to reduce production levels due to a declining demand for flue-cured tobacco. Many tobacco producers are currently diversifying into other crops. Some of these crops require curing and/or storage. Because of high capital costs to purchase conventional curing and/or storage facilities, tobacco producers wish to reduce their initial diversification costs by modifying their existing tobacco kilns (tobacco drying structures) and/or tobacco storage barns for this purpose. The investigation included high profile and low profile downdraft stick kilns, bulk kilns, and tobacco storage (pack) barns. Corn, peanuts, and hay were considered in relation to bulk kiln specifications and modifications, handling, drying and storage methods, energy requirements, cost, and quality of end product. The conclusions drawn from the study of each product are presented. Results from the projects indicate that: shelled corn can be dried from about 26% moisture content (w.b.) or less; baled hay can be dried from about 27% moisture content (w.b.) or less; and peanuts cured at airflow rates ranging from 169 to 645 l/s/m/sup 3/ of peanuts exhibited no significant differences when evaluated for appearance and flavour. 1 ref., 23 figs., 15 tabs.

  1. Mild hypothermia attenuates changes in respiratory system mechanics and modifies cytokine concentration in bronchoalveolar lavage fluid during low lung volume ventilation.

    Science.gov (United States)

    Dostál, P; Senkeřík, M; Pařízková, R; Bareš, D; Zivný, P; Zivná, H; Cerný, V

    2010-01-01

    Hypothermia was shown to attenuate ventilator-induced lung injury due to large tidal volumes. It is unclear if the protective effect of hypothermia is maintained under less injurious mechanical ventilation in animals without previous lung injury. Tracheostomized rats were randomly allocated to non-ventilated group (group C) or ventilated groups of normothermia (group N) and mild hypothermia (group H). After two hours of mechanical ventilation with inspiratory fraction of oxygen 1.0, respiratory rate 60 min(-1), tidal volume 10 ml x kg(-1), positive end-expiratory pressure (PEEP) 2 cm H2O or immediately after tracheostomy in non-ventilated animals inspiratory pressures were recorded, rats were sacrificed, pressure-volume (PV) curve of respiratory system constructed, bronchoalveolar lavage (BAL) fluid and aortic blood samples obtained. Group N animals exhibited a higher rise in peak inspiratory pressures in comparison to group H animals. Shift of the PV curve to right, higher total protein and interleukin-6 levels in BAL fluid were observed in normothermia animals in comparison with hypothermia animals and non-ventilated controls. Tumor necrosis factor-alpha was lower in the hypothermia group in comparison with normothermia and non-ventilated groups. Mild hypothermia attenuated changes in respiratory system mechanics and modified cytokine concentration in bronchoalveolar lavage fluid during low lung volume ventilation in animals without previous lung injury.

  2. A CFT perspective on gravitational dressing and bulk locality

    Energy Technology Data Exchange (ETDEWEB)

    Lewkowycz, Aitor; Turiaci, Gustavo J. [Physics Department, Princeton University,Princeton, NJ 08544 (United States); Verlinde, Herman [Physics Department, Princeton University,Princeton, NJ 08544 (United States); Princeton Center for Theoretical Science, Princeton University,Princeton, NJ 08544 (United States)

    2017-01-02

    We revisit the construction of local bulk operators in AdS/CFT with special focus on gravitational dressing and its consequences for bulk locality. Specializing to 2+1-dimensions, we investigate these issues via the proposed identification between bulk operators and cross-cap boundary states. We obtain explicit expressions for correlation functions of bulk fields with boundary stress tensor insertions, and find that they are free of non-local branch cuts but do have non-local poles. We recover the HKLL recipe for restoring bulk locality for interacting fields as the outcome of a natural CFT crossing condition. We show that, in a suitable gauge, the cross-cap states solve the bulk wave equation for general background geometries, and satisfy a conformal Ward identity analogous to a soft graviton theorem. Virasoro symmetry, the large N conformal bootstrap and the uniformization theorem all play a key role in our derivations.

  3. Bianchi type I universe in brane world scenario with non-zero Weyl tensor of the bulk

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhuri, S. [University of Burdwan, Department of Physics, Burdwan (India)

    2017-09-15

    In the paper, we present exact solutions of gravitational field equations for an anisotropic brane with a Bianchi type I universe with perfect fluid having non-vanishing Weyl tensor of the bulk. It is assumed that the thermodynamic pressure bears a linear relation with the energy density. For a particular non-zero value of the pressure the solutions are obtained in an exact analytic form with and without the cosmological constant for a Bianchi type I universe. The relevant physical quantities associated with the evolution of the universe are also derived in the two cases. (orig.)

  4. Humidification and secretion volume in mechanically ventilated patients.

    Science.gov (United States)

    Solomita, Mario; Palmer, Lucy B; Daroowalla, Feroza; Liu, Jeffrey; Miller, Dori; LeBlanc, Deniese S; Smaldone, Gerald C

    2009-10-01

    To determine potential effects of humidification on the volume of airway secretions in mechanically ventilated patients. Water vapor delivery from devices providing non-heated-wire humidification, heated-wire humidification, and heat and moisture exchanger (HME) were quantified on the bench. Then, patients requiring 24-hour mechanical ventilation were exposed sequentially to each of these humidification devices, and secretions were removed and measured by suctioning every hour during the last 4 hours of the 24-hour study period. In vitro water vapor delivery was greater using non-heated-wire humidification, compared to heated-wire humidification and HME. In vivo, a total of 9 patients were studied. Secretion volume following humidification by non-heated-wire humidification was significantly greater than for heated-wire humidification and HME (P=.004). The volume of secretions appeared to be linked to humidification, as greater water vapor delivery measured in vitro was associated with greater secretion volume in vivo.

  5. Potential risk for bacterial contamination in conventional reused ventilator systems and disposable closed ventilator-suction systems.

    Science.gov (United States)

    Li, Ya-Chi; Lin, Hui-Ling; Liao, Fang-Chun; Wang, Sing-Siang; Chang, Hsiu-Chu; Hsu, Hung-Fu; Chen, Sue-Hsien; Wan, Gwo-Hwa

    2018-01-01

    Few studies have investigated the difference in bacterial contamination between conventional reused ventilator systems and disposable closed ventilator-suction systems. The aim of this study was to investigate the bacterial contamination rates of the reused and disposable ventilator systems, and the association between system disconnection and bacterial contamination of ventilator systems. The enrolled intubated and mechanically ventilated patients used a conventional reused ventilator system and a disposable closed ventilator-suction system, respectively, for a week; specimens were then collected from the ventilator circuit systems to evaluate human and environmental bacterial contamination. The sputum specimens from patients were also analyzed in this study. The detection rate of bacteria in the conventional reused ventilator system was substantially higher than that in the disposable ventilator system. The inspiratory and expiratory limbs of the disposable closed ventilator-suction system had higher bacterial concentrations than the conventional reused ventilator system. The bacterial concentration in the heated humidifier of the reused ventilator system was significantly higher than that in the disposable ventilator system. Positive associations existed among the bacterial concentrations at different locations in the reused and disposable ventilator systems, respectively. The predominant bacteria identified in the reused and disposable ventilator systems included Acinetobacter spp., Bacillus cereus, Elizabethkingia spp., Pseudomonas spp., and Stenotrophomonas (Xan) maltophilia. Both the reused and disposable ventilator systems had high bacterial contamination rates after one week of use. Disconnection of the ventilator systems should be avoided during system operation to decrease the risks of environmental pollution and human exposure, especially for the disposable ventilator system. ClinicalTrials.gov PRS / NCT03359148.

  6. Computational Design of Non-natural Sugar Alcohols to Increase Thermal Storage Density: Beyond Existing Organic Phase Change Materials.

    Science.gov (United States)

    Inagaki, Taichi; Ishida, Toyokazu

    2016-09-14

    Thermal storage, a technology that enables us to control thermal energy, makes it possible to reuse a huge amount of waste heat, and materials with the ability to treat larger thermal energy are in high demand for energy-saving societies. Sugar alcohols are now one promising candidate for phase change materials (PCMs) because of their large thermal storage density. In this study, we computationally design experimentally unknown non-natural sugar alcohols and predict their thermal storage density as a basic step toward the development of new high performance PCMs. The non-natural sugar alcohol molecules are constructed in silico in accordance with the previously suggested molecular design guidelines: linear elongation of a carbon backbone, separated distribution of OH groups, and even numbers of carbon atoms. Their crystal structures are then predicted using the random search method and first-principles calculations. Our molecular simulation results clearly demonstrate that the non-natural sugar alcohols have potential ability to have thermal storage density up to ∼450-500 kJ/kg, which is significantly larger than the maximum thermal storage density of the present known organic PCMs (∼350 kJ/kg). This computational study suggests that, even in the case of H-bonded molecular crystals where the electrostatic energy contributes mainly to thermal storage density, the molecular distortion and van der Waals energies are also important factors to increase thermal storage density. In addition, the comparison between the three eight-carbon non-natural sugar alcohol isomers indicates that the selection of preferable isomers is also essential for large thermal storage density.

  7. Do new anesthesia ventilators deliver small tidal volumes accurately during volume-controlled ventilation?

    Science.gov (United States)

    Bachiller, Patricia R; McDonough, Joseph M; Feldman, Jeffrey M

    2008-05-01

    During mechanical ventilation of infants and neonates, small changes in tidal volume may lead to hypo- or hyperventilation, barotrauma, or volutrauma. Partly because breathing circuit compliance and fresh gas flow affect tidal volume delivery by traditional anesthesia ventilators in volume-controlled ventilation (VCV) mode, pressure-controlled ventilation (PCV) using a circle breathing system has become a common approach to minimizing the risk of mechanical ventilation for small patients, although delivered tidal volume is not assured during PCV. A new generation of anesthesia machine ventilators addresses the problems of VCV by adjusting for fresh gas flow and for the compliance of the breathing circuit. In this study, we evaluated the accuracy of new anesthesia ventilators to deliver small tidal volumes. Four anesthesia ventilator systems were evaluated to determine the accuracy of volume delivery to the airway during VCV at tidal volume settings of 100, 200, and 500 mL under different conditions of breathing circuit compliance (fully extended and fully contracted circuits) and lung compliance. A mechanical test lung (adult and infant) was used to simulate lung compliances ranging from 0.0025 to 0.03 L/cm H(2)O. Volumes and pressures were measured using a calibrated screen pneumotachograph and custom software. We tested the Smartvent 7900, Avance, and Aisys anesthesia ventilator systems (GE Healthcare, Madison, WI) and the Apollo anesthesia ventilator (Draeger Medical, Telford, PA). The Smartvent 7900 and Avance ventilators use inspiratory flow sensors to control the volume delivered, whereas the Aisys and Apollo ventilators compensate for the compliance of the circuit. We found that the anesthesia ventilators that use compliance compensation (Aisys and Apollo) accurately delivered both large and small tidal volumes to the airway of the test lung under conditions of normal and low lung compliance during VCV (ranging from 95.5% to 106.2% of the set tidal volume

  8. Should bulk cloudwater or fogwater samples obey Henry's law?

    Science.gov (United States)

    Pandis, Spyros N.; Seinfeld, John H.

    1991-06-01

    Mixing of droplets with different pH that are individually in Henry's law equilibrium with the surrounding atmosphere always results in a bulk mixture that is supersaturated with weak acids like S(IV) and HCOOH, and bases like NH3 with respect to the original atmosphere. High supersaturations result only when the pH of the bulk droplet mixture exceeds the pKa of the species, in which pH range large pH differences among droplets of different sizes lead to large deviations from Henry's law for the bulk mixture. The deviation is shown to depend on the ratio of the arithmetic mean to the harmonic mean of the hydrogen ion concentrations of the droplets with the liquid water content used as weighting factor in the calculation of the means. The theory developed can explain observed discrepancies from Henry's law in atmospheric samples and also other observed phenomena like the reported increase of pH values of bulk aqueous samples during storage.

  9. Factors Predicting Ventilator Dependence in Patients with Ventilator-Associated Pneumonia

    Directory of Open Access Journals (Sweden)

    Chia-Cheng Tseng

    2012-01-01

    Full Text Available Objectives. To determine risk factors associated with ventilator dependence in patients with ventilator-associated pneumonia (VAP. Study Design. A retrospective study was conducted at Chang Gung Memorial Hospital, Kaohsiung, from January 1, 2007 to January 31, 2008. Methods. This study evaluated 163 adult patients (aged ≥18 years. Eligibility was evaluated according to the criterion for VAP, Sequential Organ Failure Assessment (SOFA score, Acute Physiological Assessment and Chronic Health Evaluation II (APACHE II score. Oxygenation index, underlying comorbidities, septic shock status, previous tracheostomy status, and factors related to pneumonia were collected for analysis. Results. Of the 163 VAP patients in the study, 90 patients survived, yielding a mortality rate of 44.8%. Among the 90 surviving patients, only 36 (40% had been weaned off ventilators at the time of discharge. Multivariate logistic regression analysis was used to identify underlying factors such as congestive cardiac failure (P=0.009, initial high oxygenation index value (P=0.04, increased SOFA scores (P=0.01, and increased APACHE II scores (P=0.02 as independent predictors of ventilator dependence. Results from the Kaplan-Meier method indicate that initial therapy with antibiotics could increase the ventilator weaning rate (log Rank test, P<0.001. Conclusions. Preexisting cardiopulmonary function, high APACHE II and SOFA scores, and high oxygenation index were the strongest predictors of ventilator dependence. Initial empiric antibiotic treatment can improve ventilator weaning rates at the time of discharge.

  10. Temperature-dependent dielectric and energy-storage properties of Pb(Zr,Sn,Ti)O{sub 3} antiferroelectric bulk ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xuefeng; Liu, Zhen; Xu, Chenhong; Cao, Fei; Wang, Genshui; Dong, Xianlin, E-mail: xldong@mail.sic.ac.cn [Key laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 200050, Shanghai (China)

    2016-05-15

    The dielectric and energy-storage properties of Pb{sub 0.99}Nb{sub 0.02}[(Zr{sub 0.60}Sn{sub 0.40}){sub 0.95}Ti{sub 0.05}]{sub 0.98}O{sub 3} (PNZST) bulk ceramics near the antiferroelectric (AFE)-ferroelectric (FE) phase boundary are investigated as a function of temperature. Three characteristic temperatures T{sub 0}, T{sub C}, T{sub 2} are obtained from the dielectric temperature spectrum. At different temperature regions (below T{sub 0}, between T{sub 0} and T{sub C}, and above T{sub C}), three types of hysteresis loops are observed as square double loop, slim loop and linear loop, respectively. The switching fields and recoverable energy density all first increase and then decrease with increasing temperature, and reach their peak values at ∼T{sub 0}. These results provide a convenient method to optimize the working temperature of antiferroelectric electronic devices through testing the temperature dependent dielectric properties of antiferroelectric ceramics.

  11. Complications of mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Drašković Biljana

    2011-01-01

    Full Text Available Mechanical ventilation of the lungs, as an important therapeutic measure, cannot be avoided in critically ill patients. However, when machines take over some of vital functions there is always a risk of complications and accidents. Complications associated with mechanical ventilation can be divided into: 1 airway-associated complications; 2 complications in the response of patients to mechanical ventilation; and 3 complications related to the patient’s response to the device for mechanical ventilation. Complications of artificial airway may be related to intubation and extubation or the endotracheal tube. Complications of mechanical ventilation, which arise because of the patient’s response to mechanical ventilation, may primarily cause significant side effects to the lungs. During the last two decades it was concluded that mechanical ventilation can worsen or cause acute lung injury. Mechanical ventilation may increase the alveolar/capillary permeability by overdistension of the lungs (volutrauma, it can exacerbate lung damage due to the recruitment/derecruitment of collapsed alveoli (atelectrauma and may cause subtle damages due to the activation of inflammatory processes (biotrauma. Complications caused by mechanical ventilation, beside those involving the lungs, can also have significant effects on other organs and organic systems, and can be a significant factor contributing to the increase of morbidity and mortality in critically ill of mechanically ventilated patients. Complications are fortunately rare and do not occur in every patient, but due to their seriousness and severity they require extensive knowledge, experience and responsibility by health-care workers.

  12. Accuracy of tidal volume delivered by home mechanical ventilation during mouthpiece ventilation

    Science.gov (United States)

    Prigent, Helene; Falaize, Line; Leroux, Karl; Santos, Dante; Vaugier, Isabelle; Orlikowski, David; Lofaso, Frederic

    2016-01-01

    The aim of our study was to evaluate efficacy and reliability of currently available ventilators for mouthpiece ventilation (MPV). Five life-support home ventilators were assessed in a bench test using different settings simulating the specificities of MPV, such as intermittent circuit disconnection and presence of continuous leaks. The intermittent disconnection of the circuit caused relevant swings in the delivered tidal volume (VT), showing a VT overshoot during the disconnection periods and a VT decrease when the interface was reconnected to the test lung. The five ventilators showed substantial differences in the number of respiratory cycles necessary to reach a stable VT in the volume-controlled setting, ranging from 1.3 ± 0.6 to 7.3 ± 1.2 cycles. These differences were less accentuated in the volume-assisted setting (MPV-dedicated mode, when available). Our data show large differences in the capacity of the different ventilators to deal with the rapidly changing respiratory load features that characterize MPV, which can be further accentuated according to the used ventilator setting. The dedicated MPV modes allow improvement in the performance of ventilators only in some defined situations. This has practical consequences for the choice of the ventilator to be used for MPV in a specific patient. PMID:27146811

  13. Bulk-edge correspondence in topological transport and pumping

    Science.gov (United States)

    Imura, Ken-Ichiro; Yoshimura, Yukinori; Fukui, Takahiro; Hatsugai, Yasuhiro

    2018-03-01

    The bulk-edge correspondence (BEC) refers to a one-to-one relation between the bulk and edge properties ubiquitous in topologically nontrivial systems. Depending on the setup, BEC manifests in different forms and govern the spectral and transport properties of topological insulators and semimetals. Although the topological pump is theoretically old, BEC in the pump has been established just recently [1] motivated by the state-of-the-art experiments using cold atoms [2, 3]. The center of mass (CM) of a system with boundaries shows a sequence of quantized jumps in the adiabatic limit associated with the edge states. Despite that the bulk is adiabatic, the edge is inevitably non-adiabatic in the experimental setup or in any numerical simulations. Still the pumped charge is quantized and carried by the bulk. Its quantization is guaranteed by a compensation between the bulk and edges. We show that in the presence of disorder the pumped charge continues to be quantized despite the appearance of non-quantized jumps.

  14. Successful use of non-invasive positive pressure ventilation in a complicated flail chest

    International Nuclear Information System (INIS)

    Al-Ansari, Mariam A.

    2006-01-01

    The current advanced trauma life support manual states that patients with significant hypoxia (namely, SaO2<90% on room air) as a result of pulmonary contusion should be intubated and ventilated within the first hour of injury. Recently, several researchers have shown improved outcomes when patients with acute respiratory failure are managed with noninvasive positive pressure ventilation (NIPPV). Trauma patients may also benefit from this therapy. We report a case of 15-year-old boy who isolated flail chest and pulmonary contusion, who was intubated in the emergency room, and was managed successfully with the NIPPV in the intensive care unit (ICU) despite, having had aspiration pneumonia early in the course of her stay. After initial stabilization, he failed a spontaneous breathing trial. Due to absence of contraindications to the use of NIPPV, the patient was extubated on day 7 (from pressure ventilation of 15 cmH2O and positive end expiratory pressure of 8 cm H2O) to immediate NIPPV use. Three days later (after a total of 50 hours of NIPPV use in the ICU) the patient was successfully discharged home. (author)

  15. Analysis on ventilation pressure of fire area in longitudinal ventilation of underground tunnel

    Science.gov (United States)

    Li, Jiaxin; Li, Yanfeng; Feng, Xiao; Li, Junmei

    2018-03-01

    In order to solve the problem of ventilation pressure loss in the fire area under the fire condition, the wind pressure loss model of the fire area is established based on the thermodynamic equilibrium relation. The semi-empirical calculation formula is obtained by using the model experiment and CFD simulation. The validity of the formula is verified. The results show that the ventilation pressure loss in the fire zone is proportional to the convective heat release rate at the critical velocity, which is inversely proportional to the upstream ventilation velocity and the tunnel cross-sectional area. The proposed formula is consistent with the law of the tunnel fire test fitting formula that results are close, in contrast, the advantage lies in a clear theoretical basis and ventilation velocity values. The resistance of road tunnel ventilation system is calculated accurately and reliably, and then an effective emergency ventilation operation program is developed. It is necessary to consider the fire zone ventilation pressure loss. The proposed ventilation pressure loss formula can be used for design calculation after thorough verification.

  16. Effect of storage conditions on graft of polypropylene non-woven fabric induced by electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jin Young; Jeun, Joon Pyo; Kang, Phil Hyun [Radiation Research Dvision for Industry and Environment, Korea Atomic Energy Research Institute, Jeongeup(Korea, Republic of)

    2015-05-15

    In this study, we fabricated effect of storage conditions on graft of polypropylene (PP) non-woven fabric induced by electron beam. The electron beam irradiations on PP non-woven fabric were carried out over a range of irradiation doses from 25 to 100 kGy to make free radicals on fabric surface. The radical measurement was established by electron spin resonance (ESR) for confirming the changes of the alkyl radical and peroxy radical according to effect of storage time, storage temperature and atmosphere. It was observed that the free radicals were increased with irradiation dose and decreased with storage time due to the continuous oxidation. However, the radical extinction was significantly delayed due to reduced mobility of radicals at extremely low temperature. The degree of graft based on the analysis of ESR was investigated. The conditions of graft reaction were set at a temperature: 60 degrees Celcius, reaction time: 6 hours and styrene monomer concentration: 20 wt%.

  17. Oral mask ventilation is more effective than face mask ventilation after nasal surgery.

    Science.gov (United States)

    Yazicioğlu, Dilek; Baran, Ilkay; Uzumcugil, Filiz; Ozturk, Ibrahim; Utebey, Gulten; Sayın, M Murat

    2016-06-01

    To evaluate and compare the face mask (FM) and oral mask (OM) ventilation techniques during anesthesia emergence regarding tidal volume, leak volume, and difficult mask ventilation (DMV) incidence. Prospective, randomized, crossover study. Operating room, training and research hospital. American Society of Anesthesiologists physical status I and II adult patients scheduled for nasal surgery. Patients in group FM-OM received FM ventilation first, followed by OM ventilation, and patients in group OM-FM received OM ventilation first, followed by FM ventilation, with spontaneous ventilation after deep extubation. The FM ventilation was applied with the 1-handed EC-clamp technique. The OM was placed only over the mouth, and the 1-handed EC-clamp technique was used again. A child's size FM was used for the OM ventilation technique, the mask was rotated, and the inferior part of the mask was placed toward the nose. The leak volume (MVleak), mean airway pressure (Pmean), and expired tidal volume (TVe) were assessed with each mask technique for 3 consecutive breaths. A mask ventilation grade ≥3 was considered DMV. DMV occurred more frequently during FM ventilation (75% with FM vs 8% with OM). In the FM-first sequence, the mean TVe was 249±61mL with the FM and 455±35mL with the OM (P=.0001), whereas in the OM-first sequence, it was 276±81mL with the FM and 409±37mL with the OM (P=.0001). Regardless of the order used, the OM technique significantly decreased the MVleak and increased the TVe when compared to the FM technique. During anesthesia emergence after nasal surgery the OM may offer an effective ventilation method as it decreases the incidence of DMV and the gas leak around the mask and provides higher tidal volume delivery compared with FM ventilation. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Production and storage stability of non alcoholic banana beverage powder.

    Science.gov (United States)

    Mugula, J K; Lyimo, M H; Kessy, F L

    1994-02-01

    Powder for an instant, non-alcoholic beverage formulation was manufactured by sundrying and ovendrying of a popular dessert ('silk') banana variety. The reconstituted beverage was organoleptically acceptable. The effect of traditional sundrying on mats and ovendrying methods on product quality was investigated. Sundrying resulted in losses of Vitamin A, C and total sugar contents by 74, 91 and 63%, while ovendrying losses were 73, 90 and 62%, respectively. Nutrient losses during storage for three months in transparent polythene bags reached 93, 93 and 70% in sundried samples and 84, 99 and 55% in ovendried samples, respectively. The moisture content of sundried and ovendried samples increased by 12 and 17%, respectively, during storage. The increase in microbial load in this period was higher in sundried samples.

  19. Development of superconductor bulk for superconductor bearing

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chan Joong; Jun, Byung Hyuk; Park, Soon Dong (and others)

    2008-08-15

    Current carrying capacity is one of the most important issues in the consideration of superconductor bulk materials for engineering applications. There are numerous applications of Y-Ba-Cu-O (YBCO) bulk superconductors e.g. magnetic levitation train, flywheel energy storage system, levitation transportation, lunar telescope, centrifugal device, magnetic shielding materials, bulk magnets etc. Accordingly, to obtain YBCO materials in the form of large, single crystals without weak-link problem is necessary. A top seeded melt growth (TSMG) process was used to fabricate single crystal YBCO bulk superconductors. The seeded and infiltration growth (IG) technique was also very promising method for the synthesis of large, single-grain YBCO bulk superconductors with good superconducting properties. 5 wt.% Ag doped Y211 green compacts were sintered at 900 .deg. C {approx} 1200 .deg.C and then a single crystal YBCO was fabricated by an infiltration method. A refinement and uniform distribution of the Y211 particles in the Y123 matrix were achieved by sintering the Ag-doped samples. This enhancement of the critical current density was ascribable to a fine dispersion of the Y211 particles, a low porosity and the presence of Ag particles. In addition, we have designed and manufactured large YBCO single domain with levitation force of 10-13 kg/cm{sup 2} using TSMG processing technique.

  20. Creep deformation of restorative resin-composites intended for bulk-fill placement.

    Science.gov (United States)

    El-Safty, S; Silikas, N; Watts, D C

    2012-08-01

    To determine the creep deformation of several "bulk-fill" resin-composite formulations in comparison with some other types. Six resin-composites; four bulk-fill and two conventional were investigated. Stainless steel split molds (4 mm × 6 mm) were used to prepare cylindrical specimens for creep testing. Specimens were thoroughly irradiated with 650 mW cm(-2). A total of 10 specimens for each material were divided into two groups (n = 5) according to the storage condition; Group A stored dry at 37 °C for 24h and Group B stored in distilled water at 37 °C in an incubator for 24h. Each specimen was loaded (20 MPa) for 2h and unloaded for 2h. The strain deformation was recorded continuously for 4h. Statistical analysis was performed using a two-way ANOVA followed by one-way ANOVA and the Bonferroni post hoc test at a significance level of a = 0.05. The maximum creep strain % ranged from 0.72% up to 1.55% for Group A and the range for Group B increased from 0.79% up to 1.80% due to water sorption. Also, the permanent set ranged from 0.14% up to 0.47% for Group A and from 0.20% up to 0.59% for Group B. Dependent on the material and storage condition, the percentage of creep strain recovery ranged between 64% and 81%. Increased filler loading in the bulk-fill materials decreased the creep strain magnitude. Creep deformation of all studied resin-composites increased with wet storage. The "bulk-fill" composites exhibited an acceptable creep deformation and within the range exhibited by other resin-composites. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  1. Ventilation Effectiveness

    DEFF Research Database (Denmark)

    Mundt, M.; Mathisen, H. M.; Moser, M.

    Improving the ventilation effectiveness allows the indoor air quality to be significantly enhanced without the need for higher air changes in the building, thereby avoiding the higher costs and energy consumption associated with increasing the ventilation rates. This Guidebook provides easy-to-un...

  2. Analysis of emergency helpline support for home ventilator dependent patients: risk management and workload

    Directory of Open Access Journals (Sweden)

    M. Chatwin

    2008-04-01

    Full Text Available From a total of 1211 adult & paediatric patients receiving home ventilation (HV supervised by Royal Brompton Hospital between 1/1/06 and 30/6/06 the respiratory support team received an average of 528 daytime calls/month and 14/month out of hours calls to a telephone helpline. Diagnoses included: neuromuscular disease, chest wall disease, COPD, obesity hypoventilation and non-COPD lung disease. 99% received non-invasive ventilation, 1% tracheostomy ventilation. 149 required 2 ventilators for near 24 hour ventilator dependency, the remainder were classified as 1 (17% 2 (33% & 3 (50% night dependency as were able to breathe spontaneously for this period. 50% used bilevel positive pressure ventilators, 48% inspiratory pressure ventilators and 2% volume ventilators. In 188 calls a home visit was carried out because of ventilator or associated equipment-related problems. Despite regular equipment servicing programme, in 188 patients there was a technical problem with the equipment which was solved in the patient's home in 64% or required replacement / parts in 22%. Of the 25 calls in which no fault was found, 13 patients were unwell at home or required hospital admission, 2 patients died within 1 month of identification of no fault. No patient was admitted as a result of technical failure of equipment. Conclusion: There is a significant workload associated with supporting HV patients. Patients / carers all received standard competency training before discharge but other calls may be reduced by a more flexible problem-solving approach. Importantly, reports in which no technical fault is found may indicate deteriorating health in the patient and require close follow-up.

  3. Longitudinal and bulk viscosities of expanded rubidium

    International Nuclear Information System (INIS)

    Zaheri, Ali Hossein Mohammad; Srivastava, Sunita; Tankeshwar, K

    2003-01-01

    First three non-vanishing sum rules for the bulk and longitudinal stress auto-correlation functions have been evaluated for liquid Rb at six thermodynamic states along the liquid-vapour coexistence curve. The Mori memory function formalism and the frequency sum rules have been used to calculate bulk and longitudinal viscosities. The results thus obtained for the ratio of bulk viscosity to shear viscosity have been compared with experimental and other theoretical predictions wherever available. The values of the bulk viscosity have been found to be more than the corresponding values of the shear viscosity for all six thermodynamic states investigated here

  4. Invasion of non-native grasses causes a drop in soil carbon storage in California grasslands

    Energy Technology Data Exchange (ETDEWEB)

    Koteen, Laura E; Harte, John [Energy and Resources Group, 310 Barrows Hall, University of California, Berkeley, CA 94720 (United States); Baldocchi, Dennis D, E-mail: lkoteen@berkeley.edu [Department of Environmental Science, Policy and Management, 137 Mulford Hall, University of California, Berkeley, CA 94720 (United States)

    2011-10-15

    Vegetation change can affect the magnitude and direction of global climate change via its effect on carbon cycling among plants, the soil and the atmosphere. The invasion of non-native plants is a major cause of land cover change, of biodiversity loss, and of other changes in ecosystem structure and function. In California, annual grasses from Mediterranean Europe have nearly displaced native perennial grasses across the coastal hillsides and terraces of the state. Our study examines the impact of this invasion on carbon cycling and storage at two sites in northern coastal California. The results suggest that annual grass invasion has caused an average drop in soil carbon storage of 40 Mg/ha in the top half meter of soil, although additional mechanisms may also contribute to soil carbon losses. We attribute the reduction in soil carbon storage to low rates of net primary production in non-native annuals relative to perennial grasses, a shift in rooting depth and water use to primarily shallow sources, and soil respiratory losses in non-native grass soils that exceed production rates. These results indicate that even seemingly subtle land cover changes can significantly impact ecosystem functions in general, and carbon storage in particular.

  5. Invasion of non-native grasses causes a drop in soil carbon storage in California grasslands

    International Nuclear Information System (INIS)

    Koteen, Laura E; Harte, John; Baldocchi, Dennis D

    2011-01-01

    Vegetation change can affect the magnitude and direction of global climate change via its effect on carbon cycling among plants, the soil and the atmosphere. The invasion of non-native plants is a major cause of land cover change, of biodiversity loss, and of other changes in ecosystem structure and function. In California, annual grasses from Mediterranean Europe have nearly displaced native perennial grasses across the coastal hillsides and terraces of the state. Our study examines the impact of this invasion on carbon cycling and storage at two sites in northern coastal California. The results suggest that annual grass invasion has caused an average drop in soil carbon storage of 40 Mg/ha in the top half meter of soil, although additional mechanisms may also contribute to soil carbon losses. We attribute the reduction in soil carbon storage to low rates of net primary production in non-native annuals relative to perennial grasses, a shift in rooting depth and water use to primarily shallow sources, and soil respiratory losses in non-native grass soils that exceed production rates. These results indicate that even seemingly subtle land cover changes can significantly impact ecosystem functions in general, and carbon storage in particular.

  6. Invasion of non-native grasses causes a drop in soil carbon storage in California grasslands

    Science.gov (United States)

    Koteen, Laura E.; Baldocchi, Dennis D.; Harte, John

    2011-10-01

    Vegetation change can affect the magnitude and direction of global climate change via its effect on carbon cycling among plants, the soil and the atmosphere. The invasion of non-native plants is a major cause of land cover change, of biodiversity loss, and of other changes in ecosystem structure and function. In California, annual grasses from Mediterranean Europe have nearly displaced native perennial grasses across the coastal hillsides and terraces of the state. Our study examines the impact of this invasion on carbon cycling and storage at two sites in northern coastal California. The results suggest that annual grass invasion has caused an average drop in soil carbon storage of 40 Mg/ha in the top half meter of soil, although additional mechanisms may also contribute to soil carbon losses. We attribute the reduction in soil carbon storage to low rates of net primary production in non-native annuals relative to perennial grasses, a shift in rooting depth and water use to primarily shallow sources, and soil respiratory losses in non-native grass soils that exceed production rates. These results indicate that even seemingly subtle land cover changes can significantly impact ecosystem functions in general, and carbon storage in particular.

  7. Temporary storage area characterization report

    International Nuclear Information System (INIS)

    1990-01-01

    The preferred alternative identified in the Remedial Investigation/Feasibility Study (RI/FS) for the Weldon Spring Quarry Bulk Wastes is to remove the wastes from the quarry and transport them by truck to temporary storage facility at the chemical plant site. To support the RI/FS, this report provides data to characterize the temporary storage area (TSA) site and to ensure the suitability of the proposed location. 31 refs., 14 figs., 7 tabs

  8. Management of mechanical ventilation during laparoscopic surgery.

    Science.gov (United States)

    Valenza, Franco; Chevallard, Giorgio; Fossali, Tommaso; Salice, Valentina; Pizzocri, Marta; Gattinoni, Luciano

    2010-06-01

    Laparoscopy is widely used in the surgical treatment of a number of diseases. Its advantages are generally believed to lie on its minimal invasiveness, better cosmetic outcome and shorter length of hospital stay based on surgical expertise and state-of-the-art equipment. Thousands of laparoscopic surgical procedures performed safely prove that mechanical ventilation during anaesthesia for laparoscopy is well tolerated by a vast majority of patients. However, the effects of pneumoperitoneum are particularly relevant to patients with underlying lung disease as well as to the increasing number of patients with higher-than-normal body mass index. Moreover, many surgical procedures are significantly longer in duration when performed with laparoscopic techniques. Taken together, these factors impose special care for the management of mechanical ventilation during laparoscopic surgery. The purpose of the review is to summarise the consequences of pneumoperitoneum on the standard monitoring of mechanical ventilation during anaesthesia and to discuss the rationale of using a protective ventilation strategy during laparoscopic surgery. The consequences of chest wall derangement occurring during pneumoperitoneum on airway pressure and central venous pressure, together with the role of end-tidal-CO2 monitoring are emphasised. Ventilatory and non-ventilatory strategies to protect the lung are discussed.

  9. METHOD OF CALCULATION OF THE NON-STATIONARY TEMPERATURE FIELD INSIDE OF THERMAL PACKED BED ENERGY STORAGE

    Directory of Open Access Journals (Sweden)

    Ermuratschii V.V.

    2014-04-01

    Full Text Available e paper presents a method of the approximate calculation of the non-stationary temperature field inside of thermal packed bed energy storages with feasible and latent heat. Applying thermoelectric models and computational methods in electrical engineering, the task of computing non-stationary heat transfer is resolved with respect to third type boundary conditions without applying differential equations of the heat transfer. For sub-volumes of the energy storage the method is executed iteratively in spatiotemporal domain. Single-body heating is modeled for each sub-volume, and modeling conditions are assumed to be identical for remained bod-ies, located in the same sub-volume. For each iteration step the boundary conditions will be represented by re-sults at the previous step. The fulfillment of the first law of thermodynamics for system “energy storage - body” is obtained by the iterative search of the mean temperature of the energy storage. Under variable boundary con-ditions the proposed method maybe applied to calculating temperature field inside of energy storages with packed beds consisted of solid material, liquid and phase-change material. The method may also be employed to compute transient, power and performance characteristics of packed bed energy storages.

  10. Performance evaluation of ventilation radiators

    International Nuclear Information System (INIS)

    Myhren, Jonn Are; Holmberg, Sture

    2013-01-01

    A ventilation radiator is a combined ventilation and heat emission unit currently of interest due to its potential for increasing energy efficiency in exhaust-ventilated buildings with warm water heating. This paper presents results of performance tests of several ventilation radiator models conducted under controlled laboratory conditions. The purpose of the study was to validate results achieved by Computational Fluid Dynamics (CFD) in an earlier study and identify possible improvements in the performance of such systems. The main focus was on heat transfer from internal convection fins, but comfort and health aspects related to ventilation rates and air temperatures were also considered. The general results from the CFD simulations were confirmed; the heat output of ventilation radiators may be improved by at least 20% without sacrificing ventilation efficiency or thermal comfort. Improved thermal efficiency of ventilation radiators allows a lower supply water temperature and energy savings both for heating up and distribution of warm water in heat pumps or district heating systems. A secondary benefit is that a high ventilation rate can be maintained all year around without risk for cold draught. -- Highlights: ► Low temperature heat emitters are currently of interest due to their potential for increasing energy efficiency. ► A ventilation radiator is a combined ventilation and heat emission unit which can be adapted to low temperature heating systems. ► We examine how ventilation radiators can be made to be more efficient in terms of energy consumption and thermal comfort. ► Current work focuses on heat transfer mechanisms and convection fin configuration of ventilation radiators

  11. Design Principles for Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per

    For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system -Hybrid Ventilation. ....... The hybrid ventilation concepts, design challenges and - principles are discussed and illustrated by four building examples....

  12. Comparative study of the thermal and power performances of a semi-transparent photovoltaic façade under different ventilation modes

    International Nuclear Information System (INIS)

    Peng, Jinqing; Lu, Lin; Yang, Hongxing; Ma, Tao

    2015-01-01

    Highlights: • A ventilated photovoltaic double-skin façade (PV-DSF) using semi-transparent a-Si was reported. • The impact of different ventilation modes on the power performance of PV-DSF was studied experimentally. • The SHGCs and U-values of PV-DSFs under different ventilation modes were calculated and compared. • An optimum operating strategy was proposed for this PV-DSF to achieve the best energy efficiency. - Abstract: This paper studied the thermal and power performances of a ventilated photovoltaic façade under different ventilation modes, and appropriate operation strategies for different weather conditions were proposed accordingly to maximize its energy conversion efficiency. This ventilated PV double-skin façade (PV-DSF) consists of an outside layer of semi-transparent amorphous silicon (a-Si) PV laminate, an inward-openable window and a 400 mm airflow cavity. Before installation, the electrical characteristics under standard testing conditions (STC) and the temperature coefficients of the semi-transparent PV module were tested and determined in the laboratory. Field measurements were carried out to investigate the impact of different ventilation modes, namely, ventilated, buoyancy-driven ventilated and non-ventilated, on the thermal and power performances of this PV-DSF. The results show that the ventilated PV-DSF provides the lowest average solar heat gain coefficient (SHGC) and the non-ventilated PV-DSF provides the best thermal insulation performance. In terms of power performance, the energy output of the ventilated PV-DSF is greater than those of the buoyancy-driven ventilated and non-ventilated PV-DSFs by 1.9% and 3%, respectively, due to its much lower operating temperature. Based on the experimental results, a conclusion was drawn that the ventilation design can not only reduce the heat gain of PV-DSF but also improve the energy conversion efficiency of PV modules by bringing down their operating temperature. In addition, an optimum

  13. Evaluation of Flammable Gas Monitoring and Ventilation System Alternatives for Double-Contained Receiver Tanks

    International Nuclear Information System (INIS)

    GUSTAVSON, R.D.

    1999-01-01

    This study identifies possible flammable gas monitoring and ventilation system alternatives to ensure adequate removal of flammable gases from the Double-Contained Receiver Tank (DCRT) primary tanks during temporary storage of small amounts of waste. The study evaluates and compares these alternatives to support closure of the Flammable Gas Unreviewed Safety Question (USQ TF-96-04330)

  14. Experimental Study on the Thermal Response of PCM Energy Storage Block with Hole Ventilation

    Directory of Open Access Journals (Sweden)

    Sunqi Zhuang

    2015-01-01

    Full Text Available Under the condition of Nanjing, the effect by the velocity variation of night ventilation on the thermal response of the south wall built by phase-change materials (PCMs blocks with different configurations has been investigated and analyzed. It shows that the thermal performance when the PCM is placed nearby inner side in hollow block is better than that of the outer side. Meanwhile, the maximum amplitude of the temperature on the interior surface when the PCM is placed at the inner side is 58.3% higher than that of the outer side. The optimal flow velocity of both A and B is 2 m/s. Meanwhile, the minimum amplitudes of the temperature on the interior surface are 1.74°C and 3.72°C as well as the retardation coefficients are 8 h and 7 h. Compared to the structure configuration without ventilation, the heat flow was reduced 38.2% and 29.3%, respectively, and the equivalent heat resistance increased by 115.8% and 88.6%.

  15. Design Procedure for Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per; Tjelflaat, Per Olaf

    Mechanical and natural ventilation systems have developed separately during many years. The natural next step in this development is development of ventilation concepts that utilises and combines the best features from each system into a new type of ventilation system - Hybrid Ventilation....... Buildings with hybrid ventilation often include other sustainable technologies and an energy optimisation requires an integrated approach in the design of the building and its mechanical systems. Therefore, the hybrid ventilation design procedure differs from the design procedure for conventional HVAC....... The first ideas on a design procedure for hybrid ventilation is presented and the different types of design methods, that is needed in different phases of the design process, is discussed....

  16. 105-H Reactor Interim Safe Storage Project Final Report

    International Nuclear Information System (INIS)

    Ison, E.G.

    2008-01-01

    The following information documents the decontamination and decommissioning of the 105-H Reactor facility, and placement of the reactor core into interim safe storage. The D and D of the facility included characterization, engineering, removal of hazardous and radiologically contaminated materials, equipment removal, decontamination, demolition of the structure, and restoration of the site. The ISS work also included construction of the safe storage enclosure, which required the installation of a new roofing system, power and lighting, a remote monitoring system, and ventilation components.

  17. The Society for Translational Medicine: clinical practice guidelines for mechanical ventilation management for patients undergoing lobectomy.

    Science.gov (United States)

    Gao, Shugeng; Zhang, Zhongheng; Brunelli, Alessandro; Chen, Chang; Chen, Chun; Chen, Gang; Chen, Haiquan; Chen, Jin-Shing; Cassivi, Stephen; Chai, Ying; Downs, John B; Fang, Wentao; Fu, Xiangning; Garutti, Martínez I; He, Jianxing; He, Jie; Hu, Jian; Huang, Yunchao; Jiang, Gening; Jiang, Hongjing; Jiang, Zhongmin; Li, Danqing; Li, Gaofeng; Li, Hui; Li, Qiang; Li, Xiaofei; Li, Yin; Li, Zhijun; Liu, Chia-Chuan; Liu, Deruo; Liu, Lunxu; Liu, Yongyi; Ma, Haitao; Mao, Weimin; Mao, Yousheng; Mou, Juwei; Ng, Calvin Sze Hang; Petersen, René H; Qiao, Guibin; Rocco, Gaetano; Ruffini, Erico; Tan, Lijie; Tan, Qunyou; Tong, Tang; Wang, Haidong; Wang, Qun; Wang, Ruwen; Wang, Shumin; Xie, Deyao; Xue, Qi; Xue, Tao; Xu, Lin; Xu, Shidong; Xu, Songtao; Yan, Tiansheng; Yu, Fenglei; Yu, Zhentao; Zhang, Chunfang; Zhang, Lanjun; Zhang, Tao; Zhang, Xun; Zhao, Xiaojing; Zhao, Xuewei; Zhi, Xiuyi; Zhou, Qinghua

    2017-09-01

    Patients undergoing lobectomy are at significantly increased risk of lung injury. One-lung ventilation is the most commonly used technique to maintain ventilation and oxygenation during the operation. It is a challenge to choose an appropriate mechanical ventilation strategy to minimize the lung injury and other adverse clinical outcomes. In order to understand the available evidence, a systematic review was conducted including the following topics: (I) protective ventilation (PV); (II) mode of mechanical ventilation [e.g., volume controlled (VCV) versus pressure controlled (PCV)]; (III) use of therapeutic hypercapnia; (IV) use of alveolar recruitment (open-lung) strategy; (V) pre-and post-operative application of positive end expiratory pressure (PEEP); (VI) Inspired Oxygen concentration; (VII) Non-intubated thoracoscopic lobectomy; and (VIII) adjuvant pharmacologic options. The recommendations of class II are non-intubated thoracoscopic lobectomy may be an alternative to conventional one-lung ventilation in selected patients. The recommendations of class IIa are: (I) Therapeutic hypercapnia to maintain a partial pressure of carbon dioxide at 50-70 mmHg is reasonable for patients undergoing pulmonary lobectomy with one-lung ventilation; (II) PV with a tidal volume of 6 mL/kg and PEEP of 5 cmH 2 O are reasonable methods, based on current evidence; (III) alveolar recruitment [open lung ventilation (OLV)] may be beneficial in patients undergoing lobectomy with one-lung ventilation; (IV) PCV is recommended over VCV for patients undergoing lung resection; (V) pre- and post-operative CPAP can improve short-term oxygenation in patients undergoing lobectomy with one-lung ventilation; (VI) controlled mechanical ventilation with I:E ratio of 1:1 is reasonable in patients undergoing one-lung ventilation; (VII) use of lowest inspired oxygen concentration to maintain satisfactory arterial oxygen saturation is reasonable based on physiologic principles; (VIII) Adjuvant drugs

  18. A comparative analysis of pulmonary ventilation-perfusion imaging with pulmonary angiography in the diagnosis of pulmonary embolism

    International Nuclear Information System (INIS)

    Wang Jincheng; Mi Hongzhi; Wang Qian; Zhang Weijun; Lu Biao; Yang Hao; Ding Jian; Lu Yao

    2001-01-01

    Objective: To assess the value of ventilation-perfusion imaging in the diagnosis of pulmonary embolism (PE). Methods: Thirty consecutive patients with clinically suspected pulmonary embolism were studied, male: female 15:15, mean age was (36.2 +- 13.9) years. The chest radiograms were obtained in all 30 patients. All patients underwent radionuclide ventilation-perfusion imaging and pulmonary angiography. Results: Of the 30 patients, 22 with lobe, multiple segment or multi-subsegment perfusion defects and normal or nearly normal ventilation images were reported as PE. 20 of them were confirmed to be with PE by pulmonary angiography, 2 patients were not confirmed. Eight of 30 patients with multiple perfusion defects, ventilative abnormalities were reported as non-PE and the diagnoses were confirmed by pulmonary angiography. The sensitivity, specificity and accuracy of diagnosis of PE by ventilation-perfusion imaging was 100%, 80.0% and 93.3% respectively. Conclusions: (1) Ventilation-perfusion imaging is one of the most valuable methods in the diagnosis of PE. (2) The results suggest that pulmonary embolism can be diagnosed non-invasively in most patients on the basis of clinical manifestation, chest radiograms and ventilation-perfusion imaging findings. (3) Pulmonary angiography is required while clinical manifestation and ventilation-perfusion imaging findings are discordant with each other

  19. The Effect of Bulk Depth and Irradiation Time on the Surface Hardness and Degree of Cure of Bulk-Fill Composites

    Directory of Open Access Journals (Sweden)

    Farahat F

    2016-09-01

    Full Text Available Statement of Problem: For many years, application of the composite restoration with a thickness less than 2 mm for achieving the minimum polymerization contraction and stress has been accepted as a principle. But through the recent development in dental material a group of resin based composites (RBCs called Bulk Fill is introduced whose producers claim the possibility of achieving a good restoration in bulks with depths of 4 or even 5 mm. Objectives: To evaluate the effect of irradiation times and bulk depths on the degree of cure (DC of a bulk fill composite and compare it with the universal type. Materials and Methods: This study was conducted on two groups of dental RBCs including Tetric N Ceram Bulk Fill and Tetric N Ceram Universal. The composite samples were prepared in Teflon moulds with a diameter of 5 mm and height of 2, 4 and 6 mm. Then, half of the samples in each depth were cured from the upper side of the mould for 20s by LED light curing unit. The irradiation time for other specimens was 40s. After 24 hours of storage in distilled water, the microhardness of the top and bottom of the samples was measured using a Future Tech (Japan- Model FM 700 Vickers hardness testing machine. Data were analyzed statistically using the one and multi way ANOVAand Tukey’s test (p = 0.050. Results: The DC of Tetric N Ceram Bulk Fill in defined irradiation time and bulk depth was significantly more than the universal type (p < 0.001. Also, the DC of both composites studied was significantly (p < 0.001 reduced by increasing the bulk depths. Increasing the curing time from 20 to 40 seconds had a marginally significant effect (p ≤ 0.040 on the DC of both bulk fill and universal studied RBC samples. Conclusions: The DC of the investigated bulk fill composite was better than the universal type in all the irradiation times and bulk depths. The studied universal and bulk fill RBCs had an appropriate DC at the 2 and 4 mm bulk depths respectively and

  20. Amyotrophic lateral sclerosis and assisted ventilation: how patients decide.

    Science.gov (United States)

    Lemoignan, Josée; Ells, Carolyn

    2010-06-01

    Throughout the course of their illness, people with amyotrophic lateral sclerosis (ALS) must make many treatment decisions; however, none has such a significant impact on quality of life and survival as decisions about assisted ventilation. The purpose of this study was to better understand the experience of decision-making about assisted ventilation for ALS patients. Using qualitative phenomenology methodology, 10 semi-structured interviews were conducted with persons with ALS and their caregivers to elicit factors that are pertinent to their decision-making process about assisted ventilation. Six main themes emerged from the interviews. (1) the meaning of the intervention - participants made a sharp distinction between non-invasive ventilation, which they viewed as a means to relieve symptoms of respiratory failure, and invasive ventilation, which they viewed as taking over their breathing and thereby saving their life when they otherwise would die, (2) the importance of context - including functional status, available supports, and financial implications, (3) the importance of values - with respect to communication, relationships, autonomy, life, and quality of life, (4) the effect of fears - particularly respiratory distress, chocking, running out of air, and the process of death itself, (5) the need for information - how use of assisted ventilation would impact daily life, how death from respiratory failure would occur, how caregivers and persons with ALS differ in their information needs and common misconceptions, and (6) adaptation to or acceptance of the intervention - a lengthy process that involved gradual familiarization with the equipment and its benefits. People with ALS and caregivers value autonomy in decision-making about assisted ventilation. Their decision-making process is neither wholly rational nor self-interested, and includes factors that health professionals should anticipate and address. Discussions about assisted ventilation and timing

  1. Hydrogen transport and storage in engineered glass microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Rambach, G.D.

    1995-04-18

    New, high strength glass microspheres filled with pressurized hydrogen exhibit densities which make them attractive for bulk hydrogen storage and transport. The membrane tensile stress at failure for our engineered glass microspheres is about 150,000 psi, permitting a threefold increase in pressure limit and storage capacity above commercial microspheres, which have been studied a decade ago and have been shown to fail at membrane stresses of 50,000 psi. Our analysis relating glass microspheres for hydrogen transport with infrastructure and economics, indicate that pressurized microspheres can be economically competitive with other forms of bulk rail and truck transport such as pressurized tube transports and liquid hydrogen trailers.

  2. Soil moisture storage and hillslope stability

    Directory of Open Access Journals (Sweden)

    A. Talebi

    2007-09-01

    Full Text Available Recently, we presented a steady-state analytical hillslope stability model to study rain-induced shallow landslides. This model is based on kinematic wave dynamics of saturated subsurface storage and the infinite slope stability assumption. Here we apply the model to investigate the effect of neglecting the unsaturated storage on the assessment of slope stability in the steady-state hydrology. For that purpose we extend the hydrological model to compute the soil pore pressure distribution over the entire flow domain. We also apply this model for hillslopes with non-constant soil depth to compare the stability of different hillslopes and to find the critical slip surface in hillslopes with different geometric characteristics. In order to do this, we incorporate more complex approaches to compute slope stability (Janbu's non-circular method and Bishop's simplified method in the steady-state analytical hillslope stability model. We compare the safety factor (FS derived from the infinite slope stability method and the more complex approach for two cases: with and without the soil moisture profile in the unsaturated zone. We apply this extended hillslope stability model to nine characteristic hillslope types with three different profile curvatures (concave, straight, convex and three different plan shapes (convergent, parallel, divergent. Overall, we find that unsaturated zone storage does not play a critical role in determining the factor of safety for shallow and deep landslides. As a result, the effect of the unsaturated zone storage on slope stability can be neglected in the steady-state hydrology and one can assume the same bulk specific weight below and above the water table. We find that steep slopes with concave profile and convergent plan shape have the least stability. We also demonstrate that in hillslopes with non-constant soil depth (possible deep landslides, the ones with convex profiles and convergent plan shapes have

  3. Synthetic materials for sealing ventilation structures in mines

    Energy Technology Data Exchange (ETDEWEB)

    Sukhanov, V V; Putilina, O.N.; Shubina, L Ya [Donetskii NII Gigeny Truda i Profzabolevanii (USSR)

    1990-11-01

    Discusses use of polyurethanes and phenol-formaldehydes for sealing ventilation barriers and voids in underground workings in coal mines. Standard mixtures used in the USSR, their composition and components are comparatively evaluated. The evaluations concentrate on health hazards to coal miners. The following aspects of polyurethane and phenol-formaldehyde use are analyzed: noxious components, component storage, mixing, foaming, hardening, emission of vapors and gases from hardening mixture, time dependence of noxious emission, effects of air velocity, air humidity and other factors on noxious emission, methods for reducing the noxious emission, health hazards to coal miners associated with the noxious emission.

  4. Grain bulk density measurement based on wireless network

    Directory of Open Access Journals (Sweden)

    Wu Fangming

    2017-01-01

    Full Text Available To know the accurate quantity of stored grain, grain density sensors must be used to measure the grain’s bulk density. However, multi-sensors should be inserted into the storage facility, to quickly collect data during the inventory checking of stored grain. In this study, the ZigBee and Wi-Fi coexistence network’s ability to transmit data collected by density sensors was investigated. A system consisting of six sensor nodes, six router nodes, one gateway and one Android Pad was assembled to measure the grain’s bulk density and calculate its quantity. The CC2530 chip with ZigBee technology was considered as the core of the information processing, and wireless nodes detection in sensor, and router nodes. ZigBee worked in difference signal channel with Wi-Fi to avoid interferences and connected with Wi-Fi module by UART serial communications interfaces in gateway. The Android Pad received the measured data through the gateway and processed this data to calculate quantity. The system enabled multi-point and real-time parameter detection inside the grain storage. Results show that the system has characteristics of good expansibility, networking flexibility and convenience.

  5. Trends in mechanical ventilation: are we ventilating our patients in the best possible way?

    Directory of Open Access Journals (Sweden)

    Raffaele L. Dellaca’

    2017-06-01

    To learn how mechanical ventilation developed in recent decades and to provide a better understanding of the actual technology and practice. To learn how and why interdisciplinary research and competences are necessary for providing the best ventilation treatment to patients. To understand which are the most relevant technical limitations in modern mechanical ventilators that can affect their performance in delivery of the treatment. To better understand and classify ventilation modes. To learn the classification, benefits, drawbacks and future perspectives of automatic ventilation tailoring algorithms.

  6. Effects of Modes, Obesity, and Body Position on Non-invasive Positive Pressure Ventilation Success in the Intensive Care Unit: A Randomized Controlled Study.

    Science.gov (United States)

    Türk, Murat; Aydoğdu, Müge; Gürsel, Gül

    2018-01-01

    Different outcomes and success rates of non-invasive positive pressure ventilation (NPPV) in patients with acute hypercapnic respiratory failure (AHRF) still pose a significant problem in intensive care units. Previous studies investigating different modes, body positioning, and obesity-associated hypoventilation in patients with chronic respiratory failure showed that these factors may affect ventilator mechanics to achieve a better minute ventilation. This study tried to compare pressure support (BiPAP-S) and average volume targeted pressure support (AVAPS-S) modes in patients with acute or acute-on-chronic hypercapnic respiratory failure. In addition, short-term effects of body position and obesity within both modes were analyzed. We conducted a randomized controlled study in a 7-bed intensive care unit. The course of blood gas analysis and differences in ventilation variables were compared between BiPAP-S (n=33) and AVAPS-S (n=29), and between semi-recumbent and lateral positions in both modes. No difference was found in the length of hospital stay and the course of PaCO2, pH, and HCO3 levels between the modes. There was a mean reduction of 5.7±4.1 mmHg in the PaCO2 levels in the AVAPS-S mode, and 2.7±2.3 mmHg in the BiPAP-S mode per session (ppositioning had no notable effect in both modes. Although the decrease in the PaCO2 levels in the AVAPS-S mode per session was remarkably high, the course was similar in both modes. Furthermore, obesity and body positioning had no prominent effect on the PaCO2 response and ventilator mechanics. Post hoc power analysis showed that the sample size was not adequate to detect a significant difference between the modes.

  7. Augmenting natural ventilation using solar heat and free cool energy for residential buildings

    Directory of Open Access Journals (Sweden)

    N. B. Geetha

    2014-03-01

    Full Text Available In many urban buildings ventilation is not sufficient that will increase the temperature and also create unhealthy atmosphere inside the room. In such buildings artificially induced ventilation through freely available energy promote comfort conditions by reducing the temperature by 2 to 3°C and also creating good circulation of fresh air inside the room. In the present work the concept of improving the ventilation by excess hot energy available during summer days from the solar flat plate collector and by storing cool energy available during the early morning hour in the Phase Change Material (PCM based storage system is attempted. An experimental setup is made to study the effect of improvement in natural ventilation and the results are reported. A visible reduction in temperature is observed through circulation of air from the bottom side of the room to the roof of the house using the stored hot and cool energy. A CFD analysis is also carried out using ANSYS-CFX software to simulate and evaluate the mass flow of air at the inlet and at the selected RTD location by matching the transient temperature profile of the simulated result with the experimental results at the selected RTD location.

  8. Hysteresis, regime shifts, and non-stationarity in aquifer recharge-storage-discharge systems

    Science.gov (United States)

    Klammler, Harald; Jawitz, James; Annable, Michael; Hatfield, Kirk; Rao, Suresh

    2016-04-01

    Based on physical principles and geological information we develop a parsimonious aquifer model for Silver Springs, one of the largest karst springs in Florida. The model structure is linear and time-invariant with recharge, aquifer head (storage) and spring discharge as dynamic variables at the springshed (landscape) scale. Aquifer recharge is the hydrological driver with trends over a range of time scales from seasonal to multi-decadal. The freshwater-saltwater interaction is considered as a dynamic storage mechanism. Model results and observed time series show that aquifer storage causes significant rate-dependent hysteretic behavior between aquifer recharge and discharge. This leads to variable discharge per unit recharge over time scales up to decades, which may be interpreted as a gradual and cyclic regime shift in the aquifer drainage behavior. Based on field observations, we further amend the aquifer model by assuming vegetation growth in the spring run to be inversely proportional to stream velocity and to hinder stream flow. This simple modification introduces non-linearity into the dynamic system, for which we investigate the occurrence of rate-independent hysteresis and of different possible steady states with respective regime shifts between them. Results may contribute towards explaining observed non-stationary behavior potentially due to hydrological regime shifts (e.g., triggered by gradual, long-term changes in recharge or single extreme events) or long-term hysteresis (e.g., caused by aquifer storage). This improved understanding of the springshed hydrologic response dynamics is fundamental for managing the ecological, economic and social aspects at the landscape scale.

  9. The growing role of noninvasive ventilation in patients requiring prolonged mechanical ventilation.

    Science.gov (United States)

    Hess, Dean R

    2012-06-01

    For many patients with chronic respiratory failure requiring ventilator support, noninvasive ventilation (NIV) is preferable to invasive support by tracheostomy. Currently available evidence does not support the use of nocturnal NIV in unselected patients with stable COPD. Several European studies have reported benefit for high intensity NIV, in which setting of inspiratory pressure and respiratory rate are selected to achieve normocapnia. There have also been studies reporting benefit for the use of NIV as an adjunct to exercise training. NIV may be useful as an adjunct to airway clearance techniques in patients with cystic fibrosis. Accumulating evidence supports the use of NIV in patients with obesity hypoventilation syndrome. There is considerable observational evidence supporting the use of NIV in patients with chronic respiratory failure related to neuromuscular disease, and one randomized controlled trial reported that the use of NIV was life-prolonging in patients with amyotrophic lateral sclerosis. A variety of interfaces can be used to provide NIV in patients with stable chronic respiratory failure. The mouthpiece is an interface that is unique in this patient population, and has been used with success in patients with neuromuscular disease. Bi-level pressure ventilators are commonly used for NIV, although there are now a new generation of intermediate ventilators that are portable, have a long battery life, and can be used for NIV and invasive applications. Pressure support ventilation, pressure controlled ventilation, and volume controlled ventilation have been used successfully for chronic applications of NIV. New modes have recently become available, but their benefits await evidence to support their widespread use. The success of NIV in a given patient population depends on selection of an appropriate patient, selection of an appropriate interface, selection of an appropriate ventilator and ventilator settings, the skills of the clinician, the

  10. Effect of percutaneous endoscopic gastrostomy on gastro-esophageal reflux in mechanically-ventilated patients.

    Science.gov (United States)

    Douzinas, Emmanuel E; Tsapalos, Andreas; Dimitrakopoulos, Antonios; Diamanti-Kandarakis, Evanthia; Rapidis, Alexandros D; Roussos, Charis

    2006-01-07

    To investigate the effect of percutaneous endoscopic gastrostomy (PEG) on gastroesophageal reflux (GER) in mechanically-ventilated patients. In a prospective, randomized, controlled study 36 patients with recurrent or persistent ventilator-associated pneumonia (VAP) and GER > 6% were divided into PEG group (n = 16) or non-PEG group (n = 20). Another 11 ventilated patients without reflux (GER Patients were strictly followed up for semi-recumbent position and control of gastric nutrient residue. A significant decrease of median (range) reflux was observed in PEG group from 7.8 (6.2 - 15.6) at baseline to 2.7 (0 - 10.4) on d 7 post-gastrostomy (P position and absence of nutrient gastric residue reduces the gastroesophageal reflux in ventilated patients.

  11. Non-destructive identification of unknown minor phases in polycrystalline bulk alloys using three-dimensional X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yiming, E-mail: yangyiming1988@outlook.com [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Xu, Liang [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Wang, Yudan; Du, Guohao [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Yang, Sam [Commonwealth Scientific and Industrial Research Organization, Melbourne, VIC 3168 (Australia); Xiao, Tiqiao, E-mail: tqxiao@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); University of Chinese Academy of Sciences, Beijing 100049 (China)

    2017-02-15

    Minor phases make considerable contributions to the mechanical and physical properties of metals and alloys. Unfortunately, it is difficult to identify unknown minor phases in a bulk polycrystalline material using conventional metallographic methods. Here, a non-destructive method based on three-dimensional X-ray diffraction (3DXRD) is developed to solve this problem. Simulation results demonstrate that this method is simultaneously able to identify minor phase grains and reveal their positions, orientations and sizes within bulk alloys. According to systematic simulations, the 3DXRD method is practicable for an extensive sample set, including polycrystalline alloys with hexagonal, orthorhombic and cubic minor phases. Experiments were also conducted to confirm the simulation results. The results for a bulk sample of aluminum alloy AA6061 show that the crystal grains of an unexpected γ-Fe (austenite) phase can be identified, three-dimensionally and nondestructively. Therefore, we conclude that the 3DXRD method is a powerful tool for the identification of unknown minor phases in bulk alloys belonging to a variety of crystal systems. This method also has the potential to be used for in situ observations of the effects of minor phases on the crystallographic behaviors of alloys. - Highlights: •A method based on 3DXRD is developed for identification of unknown minor phase. •Grain position, orientation and size, is simultaneously acquired. •A systematic simulation demonstrated the applicability of the proposed method. •Experimental results on a AA6061 sample confirmed the practicability of the method.

  12. VENTILATION TECHNOLOGY SYSTEMS ANALYSIS

    Science.gov (United States)

    The report gives results of a project to develop a systems analysis of ventilation technology and provide a state-of-the-art assessment of ventilation and indoor air quality (IAQ) research needs. (NOTE: Ventilation technology is defined as the hardware necessary to bring outdoor ...

  13. Using a Ventilation Controller to Optimize Residential Passive Ventilation For Energy and Indoor Air Quality

    Energy Technology Data Exchange (ETDEWEB)

    Turner, William [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-08-01

    One way to reduce the energy impact of providing residential ventilation is to use passive and hybrid systems. However, these passive and hybrid (sometimes called mixed-mode) systems must still meet chronic and acute health standards for ventilation. This study uses a computer simulation approach to examine the energy and indoor air quality (IAQ) implications of passive and hybrid ventilation systems, in 16 California climate zones. Both uncontrolled and flow controlled passive stacks are assessed. A new hybrid ventilation system is outlined that uses an intelligent ventilation controller to minimise energy use, while ensuring chronic and acute IAQ standards are met. ASHRAE Standard 62.2-2010 – the United States standard for residential ventilation - is used as the chronic standard, and exposure limits for PM2.5, formaldehyde and NO2 are used as the acute standards.The results show that controlled passive ventilation and hybrid ventilation can be used in homes to provide equivalent IAQ to continuous mechanical ventilation, for less use of energy.

  14. Performance comparison of 15 transport ventilators.

    Science.gov (United States)

    Chipman, Daniel W; Caramez, Maria P; Miyoshi, Eriko; Kratohvil, Joseph P; Kacmarek, Robert M

    2007-06-01

    Numerous mechanical ventilators are designed and marketed for use in patient transport. The complexity of these ventilators differs considerably, but very few data exist to compare their operational capabilities. Using bench and animal models, we studied 15 currently available transport ventilators with regard to their physical characteristics, gas consumption (duration of an E-size oxygen cylinder), battery life, ease of use, need for compressed gas, ability to deliver set ventilation parameters to a test lung under 3 test conditions, and ability to maintain ventilation and oxygenation in normal and lung-injured sheep. Most of the ventilators tested were relatively simple to operate and had clearly marked controls. Oxygen cylinder duration ranged from 30 min to 77 min. Battery life ranged from 70 min to 8 hours. All except 3 of the ventilators were capable of providing various F(IO2) values. Ten of the ventilators had high-pressure and patient-disconnect alarms. Only 6 of the ventilators were able to deliver all settings as specifically set on the ventilator during the bench evaluation. Only 4 of the ventilators were capable of maintaining ventilation, oxygenation, and hemodynamics in both the normal and the lung-injured sheep. Only 2 of the ventilators met all the trial targets in all the bench and animal tests. With many of the ventilators, certain of the set ventilation parameters were inaccurate (differed by > 10% from the values from a cardiopulmonary monitor). The physical characteristics and high gas consumption of some of these ventilators may render them less desirable for patient transport.

  15. 46 CFR 45.131 - Ventilators.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Ventilators. 45.131 Section 45.131 Shipping COAST GUARD....131 Ventilators. (a) Ventilators passing through superstructures other than enclosed superstructures must have coamings of steel or equivalent material at the freeboard deck. (b) Ventilators in position 1...

  16. Patient-ventilator asynchrony, leaks and sleep in patients with amyotrophic lateral sclerosis.

    Science.gov (United States)

    Vrijsen, Bart; Testelmans, Dries; Belge, Catharina; Vanpee, Goele; Van Damme, Philip; Buyse, Bertien

    2016-01-01

    Sleeping with non-invasive ventilation (NIV) in amyotrophic lateral sclerosis appears to be accompanied by a high patient-ventilator asynchrony (PVA) index. This prospective observational cohort study quantifies PVA and leaks, and searches for effects of these events on sleep after polysomnographic NIV titration. Full-video polysomnography, with incorporation of transcutaneous carbon dioxide and ventilator software, was used to analyse sleep epoch-by-epoch and respiratory events and PVA breath-by-breath in 35 patients (17 non-bulbar). After diagnostic polysomnography, NIV was titrated during three consecutive nights. Sleep, PVA and leaks were evaluated at discharge and after one month. Results showed that non-bulbar patients improved in sleep architecture and oxygen and carbon dioxide levels while bulbar patients only improved oxygen saturation. PVA remained present at discharge (non-bulbar 54 (21-101) and bulbar 31 (9-39)/h sleep) and one month (non-bulbar 31 (9-39) and bulbar 32 (17-55)/h sleep), with ineffective effort as most prominent asynchrony. Leaks also persisted after titration (non-bulbar 16.6 (3.1-44.6) and bulbar 5.1 (0.0-19.5)% of total sleep time (TST)) and one month (non-bulbar 7.7 (1.4-29.3) and bulbar 12.7 (0.0-35.2)% TST). PVA and leaks have none to minor effect on sleep architecture. In conclusion, although PVA and leaks remain present after meticulous NIV titration, these events seem not to interfere with sleep.

  17. Characteristics of rain penetration through a gravity ventilator used for natural ventilation.

    Science.gov (United States)

    Kim, Taehyeung; Lee, Dong Ho; Ahn, Kwangseog; Ha, Hyunchul; Park, Heechang; Piao, Cheng Xu; Li, Xiaoyu; Seo, Jeoungyoon

    2008-01-01

    Gravity ventilators rely simply on air buoyancy to extract air and are widely used to exhaust air contaminants and heat from workplaces using minimal energy. They are designed to maximize the exhaust flow rate, but the rain penetration sometimes causes malfunctioning. In this study, the characteristics of rain penetration through a ventilator were examined as a preliminary study to develop a ventilator with the maximum exhaust capacity while minimizing rain penetration. A model ventilator was built and exposed to artificial rain and wind. The paths, intensities and amounts of penetration through the ventilator were observed and measured in qualitative and quantitative fashions. In the first phase, the pathways and intensities of rain penetration were visually observed. In the second phase, the amounts of rain penetration were quantitatively measured under the different configurations of ventilator components that were installed based on the information obtained in the first-phase experiment. The effects of wind speed, grill direction, rain drainage width, outer wall height, neck height and leaning angle of the outer wall from the vertical position were analyzed. Wind speed significantly affected rain penetration. Under the low crosswind conditions, the rain penetration intensities were under the limit of detection. Under the high crosswind conditions, grill direction and neck height were the most significant factors in reducing rain penetration. The installation of rain drainage was also important in reducing rain penetration. The experimental results suggest that, with proper configurations of its components, a gravity ventilator can be used for natural ventilation without significant rain penetration problems.

  18. Increasing the efficiency of tape-based storage backends

    CERN Document Server

    Bessone, N; Murray, S; Taurelli, G; CERN. Geneva. IT Department

    2010-01-01

    HSM systems such as the CERN’s Advanced STORage manager (CASTOR) [1] are responsible for storing Petabytes of data which is first cached on disk and then persistently stored on tape media. The contents of these tapes are regularly repacked from older, lower-density media to new-generation, higher-density media in order to free up physical space and ensure long term data integrity and availability. With the evolution of price decay and higher capacity of disk (and flash memory) based storage, our future vision for tape usage is to move away from serving on demand, random, per-file access to non-disk cached files, and to move towards loosely coupled, efficient bulk data transfers where large-volume data sets are stored and retrieved in aggregations, fully exploiting the stream-based nature of tape media. Mechanisms for grouped migration policies and priorities have been implemented, and an innovative tape format optimized for data aggregations is being developed. This new tape format will also allow for incre...

  19. Variable versus conventional lung protective mechanical ventilation during open abdominal surgery (PROVAR): a randomised controlled trial

    NARCIS (Netherlands)

    Spieth, P. M.; Güldner, A.; Uhlig, C.; Bluth, T.; Kiss, T.; Conrad, C.; Bischlager, K.; Braune, A.; Huhle, R.; Insorsi, A.; Tarantino, F.; Ball, L.; Schultz, M. J.; Abolmaali, N.; Koch, T.; Pelosi, P.; Gama de Abreu, M.

    2018-01-01

    Experimental studies showed that controlled variable ventilation (CVV) yielded better pulmonary function compared to non-variable ventilation (CNV) in injured lungs. We hypothesized that CVV improves intraoperative and postoperative respiratory function in patients undergoing open abdominal surgery.

  20. High tidal volume ventilation in infant mice.

    Science.gov (United States)

    Cannizzaro, Vincenzo; Zosky, Graeme R; Hantos, Zoltán; Turner, Debra J; Sly, Peter D

    2008-06-30

    Infant mice were ventilated with either high tidal volume (V(T)) with zero end-expiratory pressure (HVZ), high V(T) with positive end-expiratory pressure (PEEP) (HVP), or low V(T) with PEEP. Thoracic gas volume (TGV) was determined plethysmographically and low-frequency forced oscillations were used to measure the input impedance of the respiratory system. Inflammatory cells, total protein, and cytokines in bronchoalveolar lavage fluid (BALF) and interleukin-6 (IL-6) in serum were measured as markers of pulmonary and systemic inflammatory response, respectively. Coefficients of tissue damping and tissue elastance increased in all ventilated mice, with the largest rise seen in the HVZ group where TGV rapidly decreased. BALF protein levels increased in the HVP group, whereas serum IL-6 rose in the HVZ group. PEEP keeps the lungs open, but provides high volumes to the entire lungs and induces lung injury. Compared to studies in adult and non-neonatal rodents, infant mice demonstrate a different response to similar ventilation strategies underscoring the need for age-specific animal models.

  1. Rapid shift and millennial-scale variations in Holocene North Pacific Intermediate Water ventilation.

    Science.gov (United States)

    Lembke-Jene, Lester; Tiedemann, Ralf; Nürnberg, Dirk; Gong, Xun; Lohmann, Gerrit

    2018-05-22

    The Pacific hosts the largest oxygen minimum zones (OMZs) in the world ocean, which are thought to intensify and expand under future climate change, with significant consequences for marine ecosystems, biogeochemical cycles, and fisheries. At present, no deep ventilation occurs in the North Pacific due to a persistent halocline, but relatively better-oxygenated subsurface North Pacific Intermediate Water (NPIW) mitigates OMZ development in lower latitudes. Over the past decades, instrumental data show decreasing oxygenation in NPIW; however, long-term variations in middepth ventilation are potentially large, obscuring anthropogenic influences against millennial-scale natural background shifts. Here, we use paleoceanographic proxy evidence from the Okhotsk Sea, the foremost North Pacific ventilation region, to show that its modern oxygenated pattern is a relatively recent feature, with little to no ventilation before six thousand years ago, constituting an apparent Early-Middle Holocene (EMH) threshold or "tipping point." Complementary paleomodeling results likewise indicate a warmer, saltier EMH NPIW, different from its modern conditions. During the EMH, the Okhotsk Sea switched from a modern oxygenation source to a sink, through a combination of sea ice loss, higher water temperatures, and remineralization rates, inhibiting ventilation. We estimate a strongly decreased EMH NPIW oxygenation of ∼30 to 50%, and increased middepth Pacific nutrient concentrations and carbon storage. Our results ( i ) imply that under past or future warmer-than-present conditions, oceanic biogeochemical feedback mechanisms may change or even switch direction, and ( ii ) provide constraints on the high-latitude North Pacific's influence on mesopelagic ventilation dynamics, with consequences for large oceanic regions. Copyright © 2018 the Author(s). Published by PNAS.

  2. Bulk density calculations from prompt gamma ray yield

    International Nuclear Information System (INIS)

    Naqvi, A.A.; Nagadi, M.M.; Al-Amoudi, O.S.B.; Maslehuddin, M.

    2006-01-01

    Full text: The gamma ray yield from a Prompt Gamma ray Neutron Activation Analysis (PGNAA) setup is a linear function of element concentration and neutron flux in a the sample with constant bulk density. If the sample bulk density varies as well, then the element concentration and the neutron flux has a nonlinear correlation with the gamma ray yield [1]. The measurement of gamma ray yield non-linearity from samples and a standard can be used to estimate the bulk density of the samples. In this study the prompt gamma ray yield from Blast Furnace Slag, Fly Ash, Silica Fumes and Superpozz cements samples have been measured as a function of their calcium and silicon concentration using KFUPM accelerator-based PGNAA setup [2]. Due to different bulk densities of the blended cement samples, the measured gamma ray yields have nonlinear correlation with calcium and silicon concentration of the samples. The non-linearity in the yield was observed to increase with gamma rays energy and element concentration. The bulk densities of the cement samples were calculated from ratio of gamma ray yield from blended cement and that from a Portland cement standard. The calculated bulk densities have good agreement with the published data. The result of this study will be presented

  3. Natural Ventilation in Atria

    DEFF Research Database (Denmark)

    Svidt, Kjeld; Heiselberg, Per; Hendriksen, Ole Juhl

    This case study comprises a monitoring programme as well as a Computational Fluid Dynamics (CFD) analysis of a natural ventilated atrium. The purpose has been to analyse the performance of a typical natural ventilation system in Denmark under both summer and winter conditions.......This case study comprises a monitoring programme as well as a Computational Fluid Dynamics (CFD) analysis of a natural ventilated atrium. The purpose has been to analyse the performance of a typical natural ventilation system in Denmark under both summer and winter conditions....

  4. Noninvasive Ventilation in Premature Neonates.

    Science.gov (United States)

    Flanagan, Keri Ann

    2016-04-01

    The use of noninvasive ventilation is a constantly evolving treatment option for respiratory disease in the premature infant. The goals of these noninvasive ventilation techniques are to improve gas exchange in the premature infant's lungs and to minimize the need for intubation and invasive mechanical ventilation. The goals of this article are to consider various uses of nasal interfaces, discuss skin care and developmental positioning concerns faced by the bedside nurse, and discuss the medical management aimed to reduce morbidity and mortality. This article explores the nursing role, the advances in medical strategies for noninvasive ventilation, and the team approach to noninvasive ventilation use in this population. Search strategy included a literature review on medical databases, such as EBSCOhost, CINAHL, PubMed, and NeoReviews. Innovative products, nursing research on developmental positioning and skin care, and advanced medical management have led to better and safer outcomes for premature infants requiring noninvasive ventilation. The medical focus of avoiding long-term mechanical ventilation would not be possible without the technology to provide noninvasive ventilation to these premature infants and the watchful eye of the nurse in terms of careful positioning, preventing skin breakdown and facial scarring, and a proper seal to maximize ventilation accuracy. This article encourages nursing-based research to quantify some of the knowledge about skin care and positioning as well as research into most appropriate uses for noninvasive ventilation devices.

  5. Comparison of 4-Dimensional Computed Tomography Ventilation With Nuclear Medicine Ventilation-Perfusion Imaging: A Clinical Validation Study

    International Nuclear Information System (INIS)

    Vinogradskiy, Yevgeniy; Koo, Phillip J.; Castillo, Richard; Castillo, Edward; Guerrero, Thomas; Gaspar, Laurie E.; Miften, Moyed; Kavanagh, Brian D.

    2014-01-01

    Purpose: Four-dimensional computed tomography (4DCT) ventilation imaging provides lung function information for lung cancer patients undergoing radiation therapy. Before 4DCT-ventilation can be implemented clinically it needs to be validated against an established imaging modality. The purpose of this work was to compare 4DCT-ventilation to nuclear medicine ventilation, using clinically relevant global metrics and radiologist observations. Methods and Materials: Fifteen lung cancer patients with 16 sets of 4DCT and nuclear medicine ventilation-perfusion (VQ) images were used for the study. The VQ-ventilation images were acquired in planar mode using Tc-99m-labeled diethylenetriamine-pentaacetic acid aerosol inhalation. 4DCT data, spatial registration, and a density-change-based model were used to compute a 4DCT-based ventilation map for each patient. The percent ventilation was calculated in each lung and each lung third for both the 4DCT and VQ-ventilation scans. A nuclear medicine radiologist assessed the VQ and 4DCT scans for the presence of ventilation defects. The VQ and 4DCT-based images were compared using regional percent ventilation and radiologist clinical observations. Results: Individual patient examples demonstrate good qualitative agreement between the 4DCT and VQ-ventilation scans. The correlation coefficients were 0.68 and 0.45, using the percent ventilation in each individual lung and lung third, respectively. Using radiologist-noted presence of ventilation defects and receiver operating characteristic analysis, the sensitivity, specificity, and accuracy of the 4DCT-ventilation were 90%, 64%, and 81%, respectively. Conclusions: The current work compared 4DCT with VQ-based ventilation using clinically relevant global metrics and radiologist observations. We found good agreement between the radiologist's assessment of the 4DCT and VQ-ventilation images as well as the percent ventilation in each lung. The agreement lessened when the data were

  6. Fire precautions at petroleum refineries and bulk storage installations

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    Topics covered in this Code of Practice include petroleum products and combustion, site evaluation for fire defence, and fire prevention, protection, detection, systems, fighting, and fire fighting facilities in storage areas. Appendices cover legal requirements and enforcement arrangements, application rates for fire water and foam, codes of practice, flammable limits of petroleum compounds, flash points and spontaneous ignition temperatures and classification of fires. (UK)

  7. Evolution of spent fuel dry storage

    Energy Technology Data Exchange (ETDEWEB)

    Standring, Paul Nicholas [International Atomic Energy Agency, Vienna (Austria). Div. of Nuclear Fuel Cycle and Waste Technology; Takats, Ferenc [TS ENERCON KFT, Budapest (Hungary)

    2016-11-15

    Around 10,000 tHM of spent fuel is discharged per year from the nuclear power plants in operation. Whilst the bulk of spent fuel is still held in at reactor pools, 24 countries have developed storage facilities; either on the reactor site or away from the reactor site. Of the 146 operational AFR storage facilities about 80 % employ dry storage; the majority being deployed over the last 20 years. This reflects both the development of dry storage technology as well as changes in politics and trading relationships that have affected spent fuel management policies. The paper describes the various approaches to the back-end of the nuclear fuel cycle for power reactor fuels and provides data on deployed storage technologies.

  8. Interfaces and ventilator settings for long-term noninvasive ventilation in COPD patients

    Directory of Open Access Journals (Sweden)

    Callegari J

    2017-06-01

    Full Text Available Jens Callegari,1 Friederike Sophie Magnet,1 Steven Taubner,1 Melanie Berger,2 Sarah Bettina Schwarz,1 Wolfram Windisch,1 Jan Hendrik Storre3,4 1Department of Pneumology, Cologne-Merheim Hospital, Kliniken der Stadt Koeln, Witten/Herdecke University Hospital, 2Department of Pneumology, Malteser Hospital St Hildegardis, Cologne, 3Department of Pneumology, University Medical Hospital, Freiburg, 4Department of Intensive Care, Sleep Medicine and Mechanical Ventilation, Asklepios Fachkliniken Munich-Gauting, Gauting, Germany Introduction: The establishment of high-intensity (HI noninvasive ventilation (NIV that targets elevated PaCO2 has led to an increase in the use of long-term NIV to treat patients with chronic hypercapnic COPD. However, the role of the ventilation interface, especially in more aggressive ventilation strategies, has not been systematically assessed.Methods: Ventilator settings and NIV compliance were assessed in this prospective cross-sectional monocentric cohort study of COPD patients with pre-existing NIV. Daytime ­arterialized blood gas analyses and lung function testing were also performed. The primary end point was the distribution among study patients of interfaces (full-face masks [FFMs] vs nasal masks [NMs] in a real-life setting.Results: The majority of the 123 patients studied used an FFM (77%, while 23% used an NM. Ventilation settings were as follows: mean ± standard deviation (SD inspiratory positive airway pressure (IPAP was 23.2±4.6 mbar and mean ± SD breathing rate was 16.7±2.4/minute. Pressure support ventilation (PSV mode was used in 52.8% of patients, while assisted pressure-controlled ventilation (aPCV was used in 47.2% of patients. Higher IPAP levels were associated with an increased use of FFMs (IPAP <21 mbar: 73% vs IPAP >25 mbar: 84%. Mean compliance was 6.5 hours/day, with no differences between FFM (6.4 hours/day and NM (6.7 hours/day users. PaCO2 assessment of ventilation quality revealed

  9. Behovstyret ventilation

    DEFF Research Database (Denmark)

    Afshari, Alireza; Heiselberg, Per; Reinhold, Claus

    2010-01-01

    I en nylig afsluttet undersøgelse er der udført en række målinger på otte udvalgte børneinstitutioner. Fire af disse med mekanisk ventilation og fire med naturlig ventilation. Formålet er at udvide den erfaringsbaserede viden om funktionen af naturlige og mekaniske ventilationsløsninger i...

  10. Mechanical ventilator - infants

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007240.htm Mechanical ventilator - infants To use the sharing features on this page, please enable JavaScript. A mechanical ventilator is a machine that assists with breathing. ...

  11. Comparison between conventional and protective one-lung ventilation for ventilator-assisted thoracic surgery.

    Science.gov (United States)

    Ahn, H J; Kim, J A; Yang, M; Shim, W S; Park, K J; Lee, J J

    2012-09-01

    Recent papers suggest protective ventilation (PV) as a primary ventilation strategy during one-lung ventilation (OLV) to reduce postoperative pulmonary morbidity. However, data regarding the advantage of the PV strategy in patients with normal preoperative pulmonary function are inconsistent, especially in the case of minimally invasive thoracic surgery. Therefore we compared conventional OLV (VT 10 ml/kg, FiO2 1.0, zero PEEP) to protective OLV (VT 6 ml/kg, FiO2 0.5, PEEP 5 cmH2O) in patients with normal preoperative pulmonary function tests undergoing video-assisted thoracic surgery. Oxygenation, respiratory mechanics, plasma interleukin-6 and malondialdehyde levels were measured at baseline, 15 and 60 minutes after OLV and 15 minutes after restoration of two-lung ventilation. PaO2 and PaO2/FiO2 were higher in conventional OLV than in protective OLV (PProtective ventilation did not provide advantages over conventional ventilation for video-assisted thoracic surgery in this group of patients with normal lung function.

  12. Ventilation of nuclear facilities

    International Nuclear Information System (INIS)

    1982-01-01

    In this work an examination is made of ventilation problems in nuclear installations, of the fuel cycle or the handling of radioactive compounds. The study covers the detection of radioactive aerosols, purification, iodine trapping, ventilation equipment and its maintenance, engineering, safety of ventilation, fire efficiency, operation, regulations and normalization [fr

  13. Characterization and bulk properties of oxides

    International Nuclear Information System (INIS)

    Sonder, E.; Connolly, T.F.

    1979-06-01

    The bulk properties of oxides are divided into two classes, intrinsic properties which depend solely on the identity of the material, and extrinsic ones, which differ for different samples of the same compound. Sources of tabulated numerical values of intrinsic properties are given and modern developments in information storage and retrieval are discussed. Extrinsic properties are shown to depend on defects and trace impurities in the samples. Techniques of trace impurity analysis are discussed and realistic limits of detection and accuracies are given for routine analyses

  14. Natural convection along a heated vertical plate immersed in a nonlinearly stratified medium: application to liquefied gas storage

    Science.gov (United States)

    Forestier, M.; Haldenwang, P.

    We consider free convection driven by a heated vertical plate immersed in a nonlinearly stratified medium. The plate supplies a uniform horizontal heat flux to a fluid, the bulk of which has a stable stratification, characterized by a non-uniform vertical temperature gradient. This gradient is assumed to have a typical length scale of variation, denoted Z0, while 0, and the physical properties of the medium.We then apply the new theory to the natural convection affecting the vapour phase in a liquefied pure gas tank (e.g. the cryogenic storage of hydrogen). It is assumed that the cylindrical storage tank is subject to a constant uniform heat flux on its lateral and top walls. We are interested in the vapour motion above a residual layer of liquid in equilibrium with the vapour. High-precision axisymmetric numerical computations show that the flow remains steady for a large range of parameters, and that a bulk stratification characterized by a quadratic temperature profile is undoubtedly present. The application of the theory permits a comparison of the numerical and analytic results, showing that the theory satisfactorily predicts the primary dynamical and thermal properties of the storage tank.

  15. The use of subcutaneous glycopyrrolate in the management of sialorrhoea and facilitating the use of non-invasive ventilation in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Cooper-Knock, Johnathan; Ahmedzai, Sam H; Shaw, Pamela

    2011-11-01

    Sialorrhoea is a recognized complication of bulbar amyotrophic lateral sclerosis (ALS) that leads to an increased risk of potentially harmful aspiration and often prevents patients from tolerating non-invasive ventilation (NIV). A case of treatment-resistant sialorrhoea in bulbar ALS is described where subcutaneous glycopyrrolate was effective without significant side-effects. The patient went on to markedly increase the length of time she could tolerate NIV each night.

  16. Impact of immunosuppression on incidence, aetiology and outcome of ventilator-associated lower respiratory tract infections.

    Science.gov (United States)

    Moreau, Anne-Sophie; Martin-Loeches, Ignacio; Povoa, Pedro; Salluh, Jorge; Rodriguez, Alejandro; Thille, Arnaud W; Diaz Santos, Emilio; Vedes, Elisa; Lobo, Suzana Margareth; Mégarbane, Bruno; Molero Silvero, Esperanza; Coelho, Luis; Argaud, Laurent; Sanchez Iniesta, Rafael; Labreuche, Julien; Rouzé, Anahita; Nseir, Saad

    2018-03-01

    The aim of this planned analysis of the prospective multinational TAVeM database was to determine the incidence, aetiology and impact on outcome of ventilator-associated lower respiratory tract infections (VA-LRTI) in immunocompromised patients.All patients receiving mechanical ventilation for >48 h were included. Immunocompromised patients (n=663) were compared with non-immunocompromised patients (n=2297).The incidence of VA-LRTI was significantly lower among immunocompromised than among non-immunocompromised patients (16.6% versus 24.2%; sub-hazard ratio 0.65, 95% CI 0.53-0.80; p<0.0001). Similar results were found regarding ventilator-associated tracheobronchitis (7.3% versus 11.6%; sub-hazard ratio 0.61, 95% CI 0.45-0.84; p=0.002) and ventilator-associated pneumonia (9.3% versus 12.7%; sub-hazard ratio 0.72, 95% CI 0.54-0.95; p=0.019). Among patients with VA-LRTI, the rates of multidrug-resistant bacteria (72% versus 59%; p=0.011) and intensive care unit mortality were significantly higher among immunocompromised than among non-immunocompromised patients (54% versus 30%; OR 2.68, 95% CI 1.78-4.02; p<0.0001). In patients with ventilator-associated pneumonia, mortality rates were higher among immunocompromised than among non-immunocompromised patients (64% versus 34%; p<0.001).Incidence of VA-LRTI was significantly lower among immunocompromised patients, but it was associated with a significantly higher mortality rate. Multidrug-resistant pathogens were more frequently found in immunocompromised patients with VA-LRTI. Copyright ©ERS 2018.

  17. Newer nonconventional modes of mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Preet Mohinder Singh

    2014-01-01

    Full Text Available The conventional modes of ventilation suffer many limitations. Although they are popularly used and are well-understood, often they fail to match the patient-based requirements. Over the years, many small modifications in ventilators have been incorporated to improve patient outcome. The ventilators of newer generation respond to patient′s demands by additional feedback systems. In this review, we discuss the popular newer modes of ventilation that have been accepted in to clinical practice. Various intensive care units over the world have found these modes to improve patient ventilator synchrony, decrease ventilator days and improve patient safety. The various modes discusses in this review are: Dual control modes (volume assured pressure support, volume support, Adaptive support ventilation, proportional assist ventilation, mandatory minute ventilation, Bi-level airway pressure release ventilation, (BiPAP, neurally adjusted ventilatory assist and NeoGanesh. Their working principles with their advantages and clinical limitations are discussed in brief.

  18. Learning about ventilators

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000458.htm Learning about ventilators To use the sharing features on this page, ... fixed or changed. How Does Being on a Ventilator Feel? A person receives medicine to remain comfortable ...

  19. The effects of smoking status and ventilation on environmental tobacco smoke concentrations in public areas of UK pubs and bars

    Science.gov (United States)

    Carrington, Joanna; Watson, Adrian F. R.; Gee, Ivan L.

    UK public houses generally allow smoking to occur and consequently customer ETS exposure can take place. To address this, in 1999 the UK Government and the hospitality industry initiated the Public Places Charter (PPC) to increase non-smoking facilities and provide better ventilation in public houses. A study involving 60 UK pubs, located in Greater Manchester, was conducted to investigate the effects of smoking area status and ventilation on ETS concentrations. ETS markers RSP, UVPM, FPM, SolPM and nicotine were sampled and analysed using established methodologies. ETS marker concentrations were significantly higher ( P mobile in these environments and tends to remain in the smoking areas. This result, together with the much higher reductions in nicotine concentrations between smoking and non-smoking areas compared to other markers, suggests that nicotine is not the most suitable marker to use in these environments as an indicator of the effectiveness of tobacco control policies. The use of ventilation systems (sophisticated HVAC systems and extractor fans in either the on or off mode) did not have a significant effect ( P > 0.05) on ETS marker concentrations in either the smoking or non-smoking areas. The PPC aims to reduce non-smoking customers' exposure through segregation and ventilation and provide customer choice though appropriate signs. This study indicates that although ETS levels are lower in non-smoking sections and signs will assist customers in reducing their exposure, some exposure will still occur because ETS was detected in non-smoking areas. Existing ventilation provision was not effective in reducing exposure and signs advertising ventilated premises may be misleading to customers. Improvements in the design and management of ventilation systems in pubs and bars are required to reduce customer exposure to ETS, if the aims of the PPC are to be met.

  20. A stereoscopic look into the bulk

    Energy Technology Data Exchange (ETDEWEB)

    Czech, Bartłomiej; Lamprou, Lampros; McCandlish, Samuel; Mosk, Benjamin [Stanford Institute for Theoretical Physics, Department of Physics, Stanford University,Stanford, CA 94305 (United States); Sully, James [Theory Group, SLAC National Accelerator LaboratoryMenlo Park, CA 94025 (United States)

    2016-07-26

    We present the foundation for a holographic dictionary with depth perception. The dictionary consists of natural CFT operators whose duals are simple, diffeomorphism-invariant bulk operators. The CFT operators of interest are the “OPE blocks,” contributions to the OPE from a single conformal family. In holographic theories, we show that the OPE blocks are dual at leading order in 1/N to integrals of effective bulk fields along geodesics or homogeneous minimal surfaces in anti-de Sitter space. One widely studied example of an OPE block is the modular Hamiltonian, which is dual to the fluctuation in the area of a minimal surface. Thus, our operators pave the way for generalizing the Ryu-Takayanagi relation to other bulk fields. Although the OPE blocks are non-local operators in the CFT, they admit a simple geometric description as fields in kinematic space — the space of pairs of CFT points. We develop the tools for constructing local bulk operators in terms of these non-local objects. The OPE blocks also allow for conceptually clean and technically simple derivations of many results known in the literature, including linearized Einstein’s equations and the relation between conformal blocks and geodesic Witten diagrams.

  1. Regional assessment of treatment in lung cancer using lung perfusion and ventilation images

    International Nuclear Information System (INIS)

    Horikoshi, Masaki; Teshima, Takeo; Yanagimachi, Tomohiro; Ogata, Yuuko; Nukiwa, Toshihiro

    2000-01-01

    In 30 patients with lung cancer undergoing non-surgical treatment, we performed perfusion lung imaging using 99m Tc-MAA and inhalation lung studies using Technegas before and after treatment and evaluated regional perfusion and ventilation status in the lung regions where bronchogenic carcinoma was located. Regional ventilation status was preserved rather than perfusion counterpart (V>P) in 18 patients (18/30=60.0%) before treatment, while the former was better than the latter in 27 patients (27/30=90.0%) after treatment, indicating that regional ventilation status improved more significantly than regional perfusion counterpart after treatment (P=0.005). We also classified the therapeutic effect for regional perfusion and ventilation status as improved, unchanged, or worsened, respectively; improvement in regional perfusion status was observed in 17 patients (56.7%) and that in regional ventilation status in 24 patients (80.0%). There was a statistically significant correlation between improved regional perfusion and ventilation status (P=0.0018) when therapeutic effect was recognized. The patients who showed improvement in regional perfusion status after treatment always showed improved regional ventilation status, but 7 patients showed either unchanged or worsened regional perfusion status after treatment, although regional ventilation status was improved. In conclusion the pulmonary vascular beds seem more vulnerable to bronchogenic carcinoma and improvement in regional perfusion status was revealed to be more difficult than that in regional ventilation status after treatment. (author)

  2. The physiology of lipid storage and use in reptiles.

    Science.gov (United States)

    Price, Edwin R

    2017-08-01

    Lipid metabolism is central to understanding whole-animal energetics. Reptiles store most excess energy in lipid form, mobilise those lipids when needed to meet energetic demands, and invest lipids in eggs to provide the primary source of energy to developing embryos. Here, I review the mechanisms by which non-avian reptiles store, transport, and use lipids. Many aspects of lipid absorption, transport, and storage appear to be similar to birds, including the hepatic synthesis of lipids from glucose substrates, the transport of triglycerides in lipoproteins, and the storage of lipids in adipose tissue, although adipose tissue in non-avian reptiles is usually concentrated in abdominal fat bodies or the tail. Seasonal changes in fat stores suggest that lipid storage is primarily for reproduction in most species, rather than for maintenance during aphagic periods. The effects of fasting on plasma lipid metabolites can differ from mammals and birds due to the ability of non-avian reptiles to reduce their metabolism drastically during extended fasts. The effect of fasting on levels of plasma ketones is species specific: β-hydroxybutyrate concentration may rise or fall during fasting. I also describe the process by which the bulk of lipids are deposited into oocytes during vitellogenesis. Although this process is sometimes ascribed to vitellogenin-based transport in reptiles, the majority of lipid deposition occurs via triglycerides packaged in very-low-density lipoproteins (VLDLs), based on physiological, histological, biochemical, comparative, and genomic evidence. I also discuss the evidence for non-avian reptiles using 'yolk-targeted' VLDLs during vitellogenesis. The major physiological states - feeding, fasting, and vitellogenesis - have different effects on plasma lipid metabolites, and I discuss the possibilities and potential problems of using plasma metabolites to diagnose feeding condition in non-avian reptiles. © 2016 Cambridge Philosophical Society.

  3. Bilevel vs ICU ventilators providing noninvasive ventilation: effect of system leaks: a COPD lung model comparison.

    Science.gov (United States)

    Ferreira, Juliana C; Chipman, Daniel W; Hill, Nicholas S; Kacmarek, Robert M

    2009-08-01

    Noninvasive positive-pressure ventilation (NPPV) modes are currently available on bilevel and ICU ventilators. However, little data comparing the performance of the NPPV modes on these ventilators are available. In an experimental bench study, the ability of nine ICU ventilators to function in the presence of leaks was compared with a bilevel ventilator using the IngMar ASL5000 lung simulator (IngMar Medical; Pittsburgh, PA) set at a compliance of 60 mL/cm H(2)O, an inspiratory resistance of 10 cm H(2)O/L/s, an expiratory resistance of 20 cm H(2)O/ L/s, and a respiratory rate of 15 breaths/min. All of the ventilators were set at 12 cm H(2)O pressure support and 5 cm H(2)O positive end-expiratory pressure. The data were collected at baseline and at three customized leaks. At baseline, all of the ventilators were able to deliver adequate tidal volumes, to maintain airway pressure, and to synchronize with the simulator, without missed efforts or auto-triggering. As the leak was increased, all of the ventilators (except the Vision [Respironics; Murrysville, PA] and Servo I [Maquet; Solna, Sweden]) needed adjustment of sensitivity or cycling criteria to maintain adequate ventilation, and some transitioned to backup ventilation. Significant differences in triggering and cycling were observed between the Servo I and the Vision ventilators. The Vision and Servo I were the only ventilators that required no adjustments as they adapted to increasing leaks. There were differences in performance between these two ventilators, although the clinical significance of these differences is unclear. Clinicians should be aware that in the presence of leaks, most ICU ventilators require adjustments to maintain an adequate tidal volume.

  4. Intraoperative mechanical ventilation strategies in patients undergoing one-lung ventilation: a meta-analysis.

    Science.gov (United States)

    Liu, Zhen; Liu, Xiaowen; Huang, Yuguang; Zhao, Jing

    2016-01-01

    Postoperative pulmonary complications (PPCs), which are not uncommon in one-lung ventilation, are among the main causes of postoperative death after lung surgery. Intra-operative ventilation strategies can influence the incidence of PPCs. High tidal volume (V T) and increased airway pressure may lead to lung injury, while pressure-controlled ventilation and lung-protective strategies with low V T may have protective effects against lung injury. In this meta-analysis, we aim to investigate the effects of different ventilation strategies, including pressure-controlled ventilation (PCV), volume-controlled ventilation (VCV), protective ventilation (PV) and conventional ventilation (CV), on PPCs in patients undergoing one-lung ventilation. We hypothesize that both PV with low V T and PCV have protective effects against PPCs in one-lung ventilation. A systematic search (PubMed, EMBASE, the Cochrane Library, and Ovid MEDLINE; in May 2015) was performed for randomized trials comparing PCV with VCV or comparing PV with CV in one-lung ventilation. Methodological quality was evaluated using the Cochrane tool for risk. The primary outcome was the incidence of PPCs. The secondary outcomes included the length of hospital stay, intraoperative plateau airway pressure (Pplateau), oxygen index (PaO2/FiO2) and mean arterial pressure (MAP). In this meta-analysis, 11 studies (436 patients) comparing PCV with VCV and 11 studies (657 patients) comparing PV with CV were included. Compared to CV, PV decreased the incidence of PPCs (OR 0.29; 95 % CI 0.15-0.57; P < 0.01) and intraoperative Pplateau (MD -3.75; 95 % CI -5.74 to -1.76; P < 0.01) but had no significant influence on the length of hospital stay or MAP. Compared to VCV, PCV decreased intraoperative Pplateau (MD -1.46; 95 % CI -2.54 to -0.34; P = 0.01) but had no significant influence on PPCs, PaO2/FiO2 or MAP. PV with low V T was associated with the reduced incidence of PPCs compared to CV. However, PCV and VCV had similar

  5. Impact of Fire Ventilation on General Ventilation in the Building

    Science.gov (United States)

    Zender-Świercz, Ewa; Telejko, Marek

    2017-10-01

    The fire of building is a threat to its users. The biggest threat is generation, during lifetime of fire, hot gases and smoke. The purpose of quick and efficient evacuation from the area covered by the fire, at first step the escape routes have to be secured from smokiness. The smoke ventilation systems are used for this purpose. The proper design and execution of smoke ventilation is important not only because of the safety, but also of the maintenance of comfort in the building at a time when there is no fire. The manuscript presents the effect of incorrectly realized smoke ventilation in the stairwell of the medium building. The analysis shows that the flaps of smoke ventilation located in the stairwell may have a significant impact on the proper functioning of mechanical ventilation in the period when there is no fire. The improperly installed or incorrect insulated components cause perturbation of air flow and they change pressure distribution in the building. The conclusion of the analysis is the need to include the entire technical equipment of the building during the design and realization of its individual elements. The impact of various installations at each other is very important, and the omission of any of them can cause disturbances in the proper work of another.

  6. Trends in mechanical ventilation: are we ventilating our patients in the best possible way?

    Science.gov (United States)

    Dellaca', Raffaele L; Veneroni, Chiara; Farre', Ramon

    2017-06-01

    This review addresses how the combination of physiology, medicine and engineering principles contributed to the development and advancement of mechanical ventilation, emphasising the most urgent needs for improvement and the most promising directions of future development. Several aspects of mechanical ventilation are introduced, highlighting on one side the importance of interdisciplinary research for further development and, on the other, the importance of training physicians sufficiently on the technological aspects of modern devices to exploit properly the great complexity and potentials of this treatment. To learn how mechanical ventilation developed in recent decades and to provide a better understanding of the actual technology and practice.To learn how and why interdisciplinary research and competences are necessary for providing the best ventilation treatment to patients.To understand which are the most relevant technical limitations in modern mechanical ventilators that can affect their performance in delivery of the treatment.To better understand and classify ventilation modes.To learn the classification, benefits, drawbacks and future perspectives of automatic ventilation tailoring algorithms.

  7. Non-Invasive Airway Cleansing with Application of Expulsion Effect of HFJV (High Frequency Jet Ventilation

    Directory of Open Access Journals (Sweden)

    A. Hermely

    2010-01-01

    Full Text Available The aim of this study was to demonstrate the effectiveness of the use of expulsion and impulsion nozzle high frequency ventilation (VFDV for cleansing respiratory system during long-term mechanical ventilation. Material and methods. Retrospective study. In the group of 198 patients presenting its own procedures and the application of inpulsive and expulsive effect of the nozzle frequency ventilation (VFDV for cleansing and maintaining a patent airway. They used high frequency jet ventilation with the possibility of expulsion and epulsion programming and assessed a total of over 8000 expulsion procedures. Changes in lung mechanics, hemodynamics, effectiveness of expulsion and the need for suction beforeexpulsion and in regular application of VFDV were monitored. Results. We statistically compared and evaluated the effectiveness of expulsion in the VFDV group of 198 patients on long-term UVP, which was effective in average of 94.9% of patients. The impact of expulsion regime on circulatory, ventilation systems and gas exchange in the lungs, including lung mechanics, were analyzed. The authors found that the application of VFDV had a substantial and statistically significant effect on hemodynamics. Application of expulsion and lavage (a technique is described statistically significantly reduced airway resistance Raw (p<0.01 and improved the levels of lung static compliance (p<0.01 compared with the prior expulsion. Changes in blood gases during the expulsion itself did not have a major impact on gas exchange in the lungs or on the pH in this group, but there was a statistically significant increase in PaO2 (p<0.05. A key finding was that when comparing the number of manipulations in the airways (suction, a radical reduction in the number of pumping was observed, if expulsion was used regularly. A statistically significant difference in the application of expulsion was detected when compared to most groups of patients (p<0.01. The number of

  8. Assessment of ventilation and indoor air pollutants in nursery and elementary schools in France.

    Science.gov (United States)

    Canha, N; Mandin, C; Ramalho, O; Wyart, G; Ribéron, J; Dassonville, C; Hänninen, O; Almeida, S M; Derbez, M

    2016-06-01

    The aim of this study was to characterize the relationship between Indoor Air Quality (IAQ) and ventilation in French classrooms. Various parameters were measured over one school week, including volatile organic compounds, aldehydes, particulate matter (PM2.5 mass concentration and number concentration), carbon dioxide (CO2 ), air temperature, and relative humidity in 51 classrooms at 17 schools. The ventilation was characterized by several indicators, such as the air exchange rate, ventilation rate (VR), and air stuffiness index (ICONE), that are linked to indoor CO2 concentration. The influences of the season (heating or non-heating), type of school (nursery or elementary), and ventilation on the IAQ were studied. Based on the minimum value of 4.2 l/s per person required by the French legislation for mechanically ventilated classrooms, 91% of the classrooms had insufficient ventilation. The VR was significantly higher in mechanically ventilated classrooms compared with naturally ventilated rooms. The correlations between IAQ and ventilation vary according to the location of the primary source of each pollutant (outdoor vs. indoor), and for an indoor source, whether it is associated with occupant activity or continuous emission. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Development of a research-oriented system for collecting mechanical ventilator waveform data.

    Science.gov (United States)

    Rehm, Gregory B; Kuhn, Brooks T; Delplanque, Jean-Pierre; Guo, Edward C; Lieng, Monica K; Nguyen, Jimmy; Anderson, Nicholas R; Adams, Jason Y

    2017-10-28

    Lack of access to high-frequency, high-volume patient-derived data, such as mechanical ventilator waveform data, has limited the secondary use of these data for research, quality improvement, and decision support. Existing methods for collecting these data are obtrusive, require high levels of technical expertise, and are often cost-prohibitive, limiting their use and scalability for research applications. We describe here the development of an unobtrusive, open-source, scalable, and user-friendly architecture for collecting, transmitting, and storing mechanical ventilator waveform data that is generalizable to other patient care devices. The system implements a software framework that automates and enforces end-to-end data collection and transmission. A web-based data management application facilitates nontechnical end users' abilities to manage data acquisition devices, mitigates data loss and misattribution, and automates data storage. Using this integrated system, we have been able to collect ventilator waveform data from >450 patients as part of an ongoing clinical study. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Development of superconducting magnetic bearing using superconducting coil and bulk superconductor

    Energy Technology Data Exchange (ETDEWEB)

    Seino, H; Nagashima, K; Arai, Y [Railway Technical Research Institute, Hikari-cho 2-8-38, Kokubunji-shi, Tokyo (Japan)], E-mail: seino@rtri.or.jp

    2008-02-01

    The authors conducted a study on superconducting magnetic bearing, which consists of superconducting rotor and stator to apply the flywheel energy-storage system for railways. In this study, high temperature bulk superconductor (HTS bulk) was combined with superconducting coils to increase the load capacity of the bearing. In the first step of the study, the thrust rolling bearing was selected for application by using liquid nitrogen cooled HTS bulk. 60mm-diameter HTS bulks and superconducting coil which generated a high gradient of magnetic field by cusp field were adopted as a rotor and a stator for superconducting magnetic bearing, respectively. The results of the static load test and the rotation test, creep of the electromagnetic forces caused by static flux penetration and AC loss due to eccentric rotation were decreased to the level without any problems in substantial use by using two HTS bulks. In the result of verification of static load capacity, levitation force (thrust load) of 8900N or more was supportable, and stable static load capacity was obtainable when weight of 460kg was levitated.

  11. Development of superconducting magnetic bearing using superconducting coil and bulk superconductor

    International Nuclear Information System (INIS)

    Seino, H; Nagashima, K; Arai, Y

    2008-01-01

    The authors conducted a study on superconducting magnetic bearing, which consists of superconducting rotor and stator to apply the flywheel energy-storage system for railways. In this study, high temperature bulk superconductor (HTS bulk) was combined with superconducting coils to increase the load capacity of the bearing. In the first step of the study, the thrust rolling bearing was selected for application by using liquid nitrogen cooled HTS bulk. 60mm-diameter HTS bulks and superconducting coil which generated a high gradient of magnetic field by cusp field were adopted as a rotor and a stator for superconducting magnetic bearing, respectively. The results of the static load test and the rotation test, creep of the electromagnetic forces caused by static flux penetration and AC loss due to eccentric rotation were decreased to the level without any problems in substantial use by using two HTS bulks. In the result of verification of static load capacity, levitation force (thrust load) of 8900N or more was supportable, and stable static load capacity was obtainable when weight of 460kg was levitated

  12. The Society for Translational Medicine: clinical practice guidelines for mechanical ventilation management for patients undergoing lobectomy

    Science.gov (United States)

    Zhang, Zhongheng; Brunelli, Alessandro; Chen, Chang; Chen, Chun; Chen, Gang; Chen, Haiquan; Chen, Jin-Shing; Cassivi, Stephen; Chai, Ying; Downs, John B.; Fang, Wentao; Fu, Xiangning; Garutti, Martínez I.; He, Jianxing; Hu, Jian; Huang, Yunchao; Jiang, Gening; Jiang, Hongjing; Jiang, Zhongmin; Li, Danqing; Li, Gaofeng; Li, Hui; Li, Qiang; Li, Xiaofei; Li, Yin; Li, Zhijun; Liu, Chia-Chuan; Liu, Deruo; Liu, Lunxu; Liu, Yongyi; Ma, Haitao; Mao, Weimin; Mao, Yousheng; Mou, Juwei; Ng, Calvin Sze Hang; Petersen, René H.; Qiao, Guibin; Rocco, Gaetano; Ruffini, Erico; Tan, Lijie; Tan, Qunyou; Tong, Tang; Wang, Haidong; Wang, Qun; Wang, Ruwen; Wang, Shumin; Xie, Deyao; Xue, Qi; Xue, Tao; Xu, Lin; Xu, Shidong; Xu, Songtao; Yan, Tiansheng; Yu, Fenglei; Yu, Zhentao; Zhang, Chunfang; Zhang, Lanjun; Zhang, Tao; Zhang, Xun; Zhao, Xiaojing; Zhao, Xuewei; Zhi, Xiuyi; Zhou, Qinghua

    2017-01-01

    Patients undergoing lobectomy are at significantly increased risk of lung injury. One-lung ventilation is the most commonly used technique to maintain ventilation and oxygenation during the operation. It is a challenge to choose an appropriate mechanical ventilation strategy to minimize the lung injury and other adverse clinical outcomes. In order to understand the available evidence, a systematic review was conducted including the following topics: (I) protective ventilation (PV); (II) mode of mechanical ventilation [e.g., volume controlled (VCV) versus pressure controlled (PCV)]; (III) use of therapeutic hypercapnia; (IV) use of alveolar recruitment (open-lung) strategy; (V) pre-and post-operative application of positive end expiratory pressure (PEEP); (VI) Inspired Oxygen concentration; (VII) Non-intubated thoracoscopic lobectomy; and (VIII) adjuvant pharmacologic options. The recommendations of class II are non-intubated thoracoscopic lobectomy may be an alternative to conventional one-lung ventilation in selected patients. The recommendations of class IIa are: (I) Therapeutic hypercapnia to maintain a partial pressure of carbon dioxide at 50–70 mmHg is reasonable for patients undergoing pulmonary lobectomy with one-lung ventilation; (II) PV with a tidal volume of 6 mL/kg and PEEP of 5 cmH2O are reasonable methods, based on current evidence; (III) alveolar recruitment [open lung ventilation (OLV)] may be beneficial in patients undergoing lobectomy with one-lung ventilation; (IV) PCV is recommended over VCV for patients undergoing lung resection; (V) pre- and post-operative CPAP can improve short-term oxygenation in patients undergoing lobectomy with one-lung ventilation; (VI) controlled mechanical ventilation with I:E ratio of 1:1 is reasonable in patients undergoing one-lung ventilation; (VII) use of lowest inspired oxygen concentration to maintain satisfactory arterial oxygen saturation is reasonable based on physiologic principles; (VIII) Adjuvant drugs

  13. 46 CFR 42.15-45 - Ventilators.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Ventilators. 42.15-45 Section 42.15-45 Shipping COAST... Conditions of Assignment of Freeboard § 42.15-45 Ventilators. (a) Ventilators in position 1 or 2 to spaces... any ventilator exceeds 351/2 inches in height it shall be specially supported. (b) Ventilators passing...

  14. A comparison of leak compensation in acute care ventilators during noninvasive and invasive ventilation: a lung model study.

    Science.gov (United States)

    Oto, Jun; Chenelle, Christopher T; Marchese, Andrew D; Kacmarek, Robert M

    2013-12-01

    Although leak compensation has been widely introduced to acute care ventilators to improve patient-ventilator synchronization in the presence of system leaks, there are no data on these ventilators' ability to prevent triggering and cycling asynchrony. The goal of this study was to evaluate the ability of leak compensation in acute care ventilators during invasive and noninvasive ventilation (NIV). Using a lung simulator, the impact of system leaks was compared on 7 ICU ventilators and 1 dedicated NIV ventilator during triggering and cycling at 2 respiratory mechanics (COPD and ARDS models) settings, various modes of ventilation (NIV mode [pressure support ventilation], and invasive mode [pressure support and continuous mandatory ventilation]), and 2 PEEP levels (5 and 10 cm H(2)O). Leak levels used were up to 35-36 L/min in NIV mode and 26-27 L/min in invasive mode. Although all of the ventilators were able to synchronize with the simulator at baseline, only 4 of the 8 ventilators synchronized to all leaks in NIV mode, and 2 of the 8 ventilators in invasive mode. The number of breaths to synchronization was higher during increasing than during decreasing leak. In the COPD model, miss-triggering occurred more frequently and required a longer time to stabilize tidal volume than in the ARDS model. The PB840 required fewer breaths to synchronize in both invasive and noninvasive modes, compared with the other ventilators (P ventilators. The PB840 and the V60 were the only ventilators to acclimate to all leaks, but there were differences in performance between these 2 ventilators. It is not clear if these differences have clinical importance.

  15. Pulmonary perfusion ''without ventilation''

    International Nuclear Information System (INIS)

    Chapman, C.N.; Sziklas, J.J.; Spencer, R.P.; Rosenberg, R.J.

    1983-01-01

    An 88-yr-old man, with prior left upper lobectomy and phrenic nerve injury, had a ventilation/perfusion lung image. Both wash-in and equilibrium ventilation images showed no radioactive gas in the left lung. Nevertheless, the left lung was perfused. A similar result was obtained on a repeat study 8 days later. Delayed images, during washout, showed some radioactive gas in the left lung. Nearly absent ventilation (but continued perfusion) of that lung might have been related to altered gas dynamics brought about by the prior lobectomy, a submucosal bronchial lesion, phrenic nerve damage, and limited motion of the left part of the diaphragm. This case raises the issue of the degree of ventilation (and the phase relationship between the lungs) required for the entry of radioactive gas into a diseased lung, and the production of a ''reversed ventilation/perfusion mismatch.''

  16. Sevoflurane posttreatment prevents oxidative and inflammatory injury in ventilator-induced lung injury.

    Directory of Open Access Journals (Sweden)

    Julie Wagner

    Full Text Available Mechanical ventilation is a life-saving clinical treatment but it can induce or aggravate lung injury. New therapeutic strategies, aimed at reducing the negative effects of mechanical ventilation such as excessive production of reactive oxygen species, release of pro-inflammatory cytokines, and transmigration as well as activation of neutrophil cells, are needed to improve the clinical outcome of ventilated patients. Though the inhaled anesthetic sevoflurane is known to exert organ-protective effects, little is known about the potential of sevoflurane therapy in ventilator-induced lung injury. This study focused on the effects of delayed sevoflurane application in mechanically ventilated C57BL/6N mice. Lung function, lung injury, oxidative stress, and inflammatory parameters were analyzed and compared between non-ventilated and ventilated groups with or without sevoflurane anesthesia. Mechanical ventilation led to a substantial induction of lung injury, reactive oxygen species production, pro-inflammatory cytokine release, and neutrophil influx. In contrast, sevoflurane posttreatment time dependently reduced histological signs of lung injury. Most interestingly, increased production of reactive oxygen species was clearly inhibited in all sevoflurane posttreatment groups. Likewise, the release of the pro-inflammatory cytokines interleukin-1β and MIP-1β and neutrophil transmigration were completely prevented by sevoflurane independent of the onset of sevoflurane administration. In conclusion, sevoflurane posttreatment time dependently limits lung injury, and oxidative and pro-inflammatory responses are clearly prevented by sevoflurane irrespective of the onset of posttreatment. These findings underline the therapeutic potential of sevoflurane treatment in ventilator-induced lung injury.

  17. Simulation of trapping properties of high κ material as the charge storage layer for flash memory application

    International Nuclear Information System (INIS)

    Yeo, Yee Ngee; Wang Yingqian; Samanta, Santanu Kumar; Yoo, Won Jong; Samudra, Ganesh; Gao, Dongyue; Chong, Chee Ching

    2006-01-01

    We investigated the trapping properties of high κ material as the charge storage layer in non-volatile flash memory devices using a two-dimensional device simulator, Medici. The high κ material is sandwiched between two silicon oxide layers, resulting in the Silicon-Oxide-High κ-Oxide-Silicon (SOHOS) structure. The trap energy levels of the bulk electron traps in high κ material were determined. The programming and erasing voltage and time using Fowler Nordheim tunneling were estimated by simulation. The effect of deep level traps on erasing was investigated. Also, the effect of bulk traps density, thickness of block oxide and thickness of high κ material on the threshold voltage of the device was simulated

  18. Effect of long-term non-invasive ventilation on quality of life and cardiac function of children's neuromuscular disorders with chronic respiratory failure: a clinical trial

    Directory of Open Access Journals (Sweden)

    Saeed Sadr

    2018-04-01

    Full Text Available Background: Use of long-term non-invasive positive pressure ventilation is increasing greatly worldwide in children with chronic respiratory failure (CRF of all ages. This treatment requires delivery of ventilation through a non-invasive interface. Cardiac function in majority of these children is impaired. The aim of this study was to assess the effect of institution of non-invasive ventilation (NIV on quality of life (QOL and cardiac function in children with CRF related to neuromuscular disorders. Methods: Information obtained from all of the children under 16 years old with CRF due to neuromuscular disorders who were on NIV for at least six months and that were referred to Mofid children's hospital, Tehran, Iran between September 1, 2013, to September 1, 2017.Based on previous studies they were assessed from the year prior to starting NIV and annually thereafter. Data obtained included diagnosis, pulmonary function test, echocardiographic data, length of hospitalizations, and health care costs. Patients and parents completed questionnaires assessing QOL with NIV and recalling QOL one year before commencing NIV. All results were recorded in information forms and data were analyzed with chi square and entered in SPSS 21. Results: Follow-up ranged from 6 to 36 months (median 18. Before and after NIV hospitalization rates (P<0.001, PICU admission (P<0.001 and health care costs decreased respectively. QOL remained stable after NIV despite disease progression (P<0.001. Systolic pulmonary arterial pressure (P=0.009 is diminished. Symptoms of daytime sleepiness (P<0.001 and headache (P<0.001 improved after initiation of NIV. Conclusions: This study revealed that use of NIV results in a reduction in PAH without adverse effects on quality of life and pulmonary function.

  19. Refractory Hyperlactatemia with Organ Insufficiency in Lipid Storage Myopathy.

    Science.gov (United States)

    Xu, Yuanda; Zhou, Li; Liang, Weibo; He, Weiqun; Liu, Xiaoqing; Liang, Xiuling; Zhong, Nanshan; Li, Yimin

    2015-08-01

    Lipid storage myopathy is a metabolic disorder characterized by abnormal lipid accumulation in muscle fibers and progressive muscle weakness. Here, we report the case of a 17-year-old woman with progressive muscle weakness, refractory hyperlactatemia, and multiple organ insufficiency. Severe pneumonia was the initial diagnosis. After anti-infective treatment, fluid resuscitation, and mechanical ventilation, the patient's symptoms improved but hyperlactatemia and muscle weakness persisted. She was empirically treated with carnitine. Biochemical tests, electromyography, and muscle biopsy confirmed lipid storage myopathy. After 7 weeks of treatment, the patient resumed normal daily life. An empirical treatment with carnitine may be beneficial for patients before an accurate diagnosis of lipid storage myopathy is made.

  20. High-Frequency Percussive Ventilation Revisited

    Science.gov (United States)

    2010-01-01

    be implemented. ‡ Follow the reverse of the ventilation sequence if respiratory alkalosis develops—however, start at ventilation goal sequence 1 not at...High-frequency percussive ventilation (HFPV) has demonstrated a potential role as a rescue option for refractory acute respiratory distress syndrome...frequency percussive ventilation (HFPV) has demon- strated a potential role as a salvage option for refrac- tory acute respiratory distress syndrome

  1. Plane Stratified Flow in a Room Ventilated by Displacement Ventilation

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm; Nickel, J.; Baron, D. J. G.

    2004-01-01

    The air movement in the occupied zone of a room ventilated by displacement ventilation exists as a stratified flow along the floor. This flow can be radial or plane according to the number of wall-mounted diffusers and the room geometry. The paper addresses the situations where plane flow...

  2. APRV Mode in Ventilator Induced Lung Injury (VILI

    Directory of Open Access Journals (Sweden)

    Ata Mahmoodpoor

    2014-01-01

    Full Text Available Ventilator-Induced Lung Injury (VILI, being a significant iatrogenic complication in the ICU patients, is associated with high morbidity and mortality. Numerous approaches, protocols and ventilation modes have been introduced and examined to decrease the incidence of VILI in the ICU patients. Airway pressure release ventilation (APRV, firstly introduced by Stock and Downs in 1987, applies higher Continuous Positive Airway Pressure (CPAP levels in prolonged periods (P and T high in order to preserve satisfactory lung volume and consequently alveolar recruitment. This mode benefits a time-cycled release phase to a lower set of pressure for a short period of time (P and T low i.e. release time (1,2. While some advantages have been introduced for APRV such as efficiently recruited alveoli over time, more homogeneous ventilation, less volutrauma, probable stabilization of patent alveoli and reduction in atelectrauma, protective effects of APRV on lung damage only seem to be substantial if spontaneous breathing responds to more than 30% of total minute ventilation (3. APRV in ARDS patients should be administered cautiously; T low<0.6 seconds, for recruiting collapsed alveoli; however overstretching of alveoli especially during P high should not be neglected and appropriate sedation considered. The proposed advantages for APRV give the impression of being outstanding; however, APRV, as a non-physiologic inverse ratio mode of ventilation, might result in inflammation mainly due to impaired patient-ventilator interaction explaining the negative or minimally desirable effects of APRV on inflammation (4. Consequently, continuous infusion of neuromuscular blocking drugs during ARDS has been reported to reduce mortality (5. There are insufficient confirming data on the superiority of APRV above other ventilatory methods in regard to oxygenation, hemodynamics, regional blood flow, patient comfort and length of mechanical ventilation. Based on current findings

  3. The effect of helium on ventilator performance: study of five ventilators and a bedside Pitot tube spirometer.

    Science.gov (United States)

    Oppenheim-Eden, A; Cohen, Y; Weissman, C; Pizov, R

    2001-08-01

    To assess in vitro the performance of five mechanical ventilators-Siemens 300 and 900C (Siemens-Elma; Solna, Sweden), Puritan Bennett 7200 (Nellcor Puritan Bennett; Pleasanton, CA), Evita 4 (Dragerwerk; Lubeck, Germany), and Bear 1000 (Bear Medical Systems; Riverside CA)-and a bedside sidestream spirometer (Datex CS3 Respiratory Module; Datex-Ohmeda; Helsinki, Finland) during ventilation with helium-oxygen mixtures. In vitro study. ICUs of two university-affiliated hospitals. Each ventilator was connected to 100% helium through compressed air inlets and then tested at three to six different tidal volume (VT) settings using various helium-oxygen concentrations (fraction of inspired oxygen [FIO(2)] of 0.2 to 1.0). FIO(2) and VT were measured with the Datex CS3 spirometer, and VT was validated with a water-displacement spirometer. The Puritan Bennett 7200 ventilator did not function with helium. With the other four ventilators, delivered FIO(2) was lower than the set FIO(2). For the Siemens 300 and 900C ventilators, this difference could be explained by the lack of 21% oxygen when helium was connected to the air supply port, while for the other two ventilators, a nonlinear relation was found. The VT of the Siemens 300 ventilator was independent of helium concentration, while for the other three ventilators, delivered VT was greater than the set VT and was dependent on helium concentration. During ventilation with 80% helium and 20% oxygen, VT increased to 125% of set VT for the Siemens 900C ventilator, and more than doubled for the Evita 4 and Bear 1000 ventilators. Under the same conditions, the Datex CS3 spirometer underestimated the delivered VT by about 33%. At present, no mechanical ventilator is calibrated for use with helium. This investigation offers correction factors for four ventilators for ventilation with helium.

  4. Effects of non-invasive ventilation and posture on chest wall volumes and motion in patients with amyotrophic lateral sclerosis: a case series

    OpenAIRE

    Magalh?es, Cristiana M.; Fregonezi, Guilherme A.; Vidigal-Lopes, Mauro; Vieira, Bruna S. P. P.; Vieira, Danielle S. R.; Parreira, Ver?nica F.

    2016-01-01

    ABSTRACT Background The effects of non-invasive ventilation (NIV) on the breathing pattern and thoracoabdominal motion of patients with amyotrophic lateral sclerosis (ALS) are unknown. Objectives 1) To analyze the influence of NIV on chest wall volumes and motion assessed by optoelectronic plethysmography in ALS patients and 2) to compare these parameters in the supine and sitting positions to those of healthy individuals (without NIV). Method Nine ALS patients were evaluated in the supine...

  5. Ventilation of nuclear power plants

    International Nuclear Information System (INIS)

    Madoyan, A.A.; Vlasik, V.F.

    1984-01-01

    Foundations and calculation methods of ventilation of rooms with different degree of heat and gas release with the change of operation mode of NPP main equipment, as well as problems of NPP site and adjoining area aerodynamics, have been presented. Systems of air ventilation and conditioning, cooling equipment, are considered. The main points of designing are described and determination of economic efficiency of the ventilation systems are made. Technical characteristics of the ventilators, conditioners, filters and air heaters used, are presented. Organization of adjustment, tests, operation and maintenance of the ventilation systems of NPP with RBMK and WWER-type reactors, is described

  6. Assessment of lung ventilation by MR imaging: current status and future perspectives

    International Nuclear Information System (INIS)

    Kauczor, Hans-Ulrich; Hanke, Alexander; Beek, Edwin J.R. van

    2002-01-01

    The aim of this paper is to review the present status of novel MRI techniques as a new important instrument for functional ventilation imaging. The current status and future perspectives in research and clinical applications are summarized. Morphological lung imaging is based on chest radiography and computed tomography, whereas scintigraphy is used for ventilation imaging. During recent years, MRI has emerged as a new means for functional imaging of ventilation. Aerosolized contrast agents and oxygen are used in proton imaging, whereas non-proton imaging relies on fluorine compounds, such as sulfur hexafluoride and perfluorcarbons, or on hyperpolarized noble gases, such as helium-3 or xenon-129. All the gases are administered as inhaled ''contrast agents'' for imaging of the airways and airspaces. In general, straightforward images demonstrate the homogeneity of ventilation in a breath-hold and allow for determination of ventilated lung. The different properties of the different compounds enable the measurement of additional functional parameters. They comprise airspace size, regional oxygen partial pressure, and analysis of ventilation distribution, ventilation/perfusion ratios, and gas exchange, including oxygen uptake. Novel MRI techniques provide the potential for functional imaging of ventilation. The next steps include definition of the value and the potential of the different contrast mechanisms as well as determination of the significance of the functional information with regard to physiological research and patient management in chronic obstructive pulmonary disease and others. (orig.)

  7. Respiratory training during rehabilitation of acute organic fluorine-poisoned patients treated by non-invasive positive pressure ventilation.

    Science.gov (United States)

    Liu, L; Liu, D Z; Wang, Q P; Zhu, Z L; Li, H M; Lu, X Y

    2017-01-01

    This paper aimed to analyze the effects of respiratory training on pulmonary function during the rehabilitation period for acute organic fluorine-poisoned patients treated by non-invasive positive pressure ventilation (NIPPV). Sixty-two acute organic fluorine-poisoned patients admitted to the Xinxiang Central Hospital, Xinxiang City, China, from May 2012 to March 2016 were selected and randomly divided into an observation group and a control group, with 31 cases in each. Both groups received NIPPV. The patients in the control group exercised daily, while the patients in the observation group received contracting lips-abdominal breathing training. The therapeutic effects, pulmonary ventilation function, serum levels of α-antitrypsin1 (α-AT1), surfactant protein D (SP-D), neutrophil elastase (NE), transforming growth factor beta 1 (TGF-β1), and quality of life were analyzed and compared between the two groups both before and after the administration of treatment. The total effective rate of the observation group was 93.55%, which was significantly higher when compared with the control group (74.19%) (P less than 0.05). The levels of forced expiratory volume in one second (FEV1), FEV1/FVC ratio, vital capacity (VC), carbon monoxide diffusion capacity (DLco), and maximal voluntary ventilation (MVV) of the observation group were better when compared with the control group and had statistical significance (P less than 0.05). Before treatment, the serum levels of α-AT1, SP-D, NE, and TGF-β1, and quality of life had no statistical significance in either group (P>0.05); after treatment, these indexes and the quality of life for the observation group were significantly higher when compared with the control group, with statistical significance (P less than 0.05). The respiratory training in acute organic fluorine-poisoned patients treated by NIPPV can improve the serum indexes, dilute toxicity, and recover pulmonary function, which play key roles in improving the

  8. Long vs. short-term energy storage:sensitivity analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Schoenung, Susan M. (Longitude 122 West, Inc., Menlo Park, CA); Hassenzahl, William V. (,Advanced Energy Analysis, Piedmont, CA)

    2007-07-01

    This report extends earlier work to characterize long-duration and short-duration energy storage technologies, primarily on the basis of life-cycle cost, and to investigate sensitivities to various input assumptions. Another technology--asymmetric lead-carbon capacitors--has also been added. Energy storage technologies are examined for three application categories--bulk energy storage, distributed generation, and power quality--with significant variations in discharge time and storage capacity. Sensitivity analyses include cost of electricity and natural gas, and system life, which impacts replacement costs and capital carrying charges. Results are presented in terms of annual cost, $/kW-yr. A major variable affecting system cost is hours of storage available for discharge.

  9. The diagnostic value of ventilation-perfusion scintigraphy combined with plasma D-dimer assay in diagnosis of pulmonary embolism

    International Nuclear Information System (INIS)

    Wang Qian; Huang Lili; Qin Shuling; Yue Minggang; Wang Yu; Nie Yuxin; Liang Tiejun

    2005-01-01

    Objective: To investigate the clinical diagnostic value of ventilation-perfusion scintigraphy combined with plasma D-dimer assay in diagnosis of pulmonary embolism (PE). Methods: One hundred and four patients with clinically suspected PE underwent both pulmonary ventilation-perfusion scintigraphy and plasma D-dimer assay. According to the criteria of prospective investigation of the pulmonary embolism diagnosis (PIOPED), ventilation-perfusion scintigraphy was interpreted as normal, very low or low probability of PE, intermediate probability of PE and high probability of PE. High probability was considered as positive; normal and very low or low probability as negative and intermediate probability as non-diagnostic. Plasma D-dimer levels were measured using a quantitative immunoturbidimetric method, and a cut-off value of 500 mg/L was used in the diagnosis of PE. Clinical diagnostic value of ventilation-perfusion scintigraphy, D-dimer assay and combined use of ventilation-perfusion scintigraphy and D-dimer assay for diagnosing PE was evaluated, respectively, comparing with the final clinical diagnosis that was based on the clinical findings. Results: Among the 104 patients, 44 were diagnosed with PE and 60 were excluded. Ventilation-perfusion scintigraphy provided diagnostic interpretations for 86 (82.7%) patients, and non-diagnostic interpretations for 18 (17.3%) patients. For diagnosing PE, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of ventilation-perfusion scintigraphy was 84.1%, 75.0%, 78.8%, 71.2% and 86.5%, respectively, and with D-dimer assay was 93.2%, 60.0%, 74.0%, 63.1% and 92.3%, respectively. If a plasma D-dimer level of < 500 mg/L was taken as a criterion to exclude PE for those intermediate probability of ventilation-perfusion scintigraphy, the diagnostic specificity and accuracy would be raised to 85.0% and 84.6%, respectively. Conclusions: When a non-diagnostic interpretation was occurred on

  10. Partial liquid ventilation improves lung function in ventilation-induced lung injury

    NARCIS (Netherlands)

    G.F. Vazquez de Anda; R.A. Lachmann; S.J.C. Verbrugge (Serge); D.A.M.P.J. Gommers (Diederik); J.J. Haitsma (Jack); B.F. Lachmann (Burkhard)

    2001-01-01

    textabstractDisturbances in lung function and lung mechanics are present after ventilation with high peak inspiratory pressures (PIP) and low levels of positive end-expiratory pressure (PEEP). Therefore, the authors investigated whether partial liquid ventilation can re-establish

  11. Intraoperative protective mechanical ventilation and risk of postoperative respiratory complications: hospital based registry study.

    Science.gov (United States)

    Ladha, Karim; Vidal Melo, Marcos F; McLean, Duncan J; Wanderer, Jonathan P; Grabitz, Stephanie D; Kurth, Tobias; Eikermann, Matthias

    2015-07-14

    To evaluate the effects of intraoperative protective ventilation on major postoperative respiratory complications and to define safe intraoperative mechanical ventilator settings that do not translate into an increased risk of postoperative respiratory complications. Hospital based registry study. Academic tertiary care hospital and two affiliated community hospitals in Massachusetts, United States. 69,265 consecutively enrolled patients over the age of 18 who underwent a non-cardiac surgical procedure between January 2007 and August 2014 and required general anesthesia with endotracheal intubation. Protective ventilation, defined as a median positive end expiratory pressure (PEEP) of 5 cmH2O or more, a median tidal volume of less than 10 mL/kg of predicted body weight, and a median plateau pressure of less than 30 cmH2O. Composite outcome of major respiratory complications, including pulmonary edema, respiratory failure, pneumonia, and re-intubation. Of the 69,265 enrolled patients 34,800 (50.2%) received protective ventilation and 34,465 (49.8%) received non-protective ventilation intraoperatively. Protective ventilation was associated with a decreased risk of postoperative respiratory complications in multivariable regression (adjusted odds ratio 0.90, 95% confidence interval 0.82 to 0.98, P=0.013). The results were similar in the propensity score matched cohort (odds ratio 0.89, 95% confidence interval 0.83 to 0.97, P=0.004). A PEEP of 5 cmH2O and median plateau pressures of 16 cmH2O or less were associated with the lowest risk of postoperative respiratory complications. Intraoperative protective ventilation was associated with a decreased risk of postoperative respiratory complications. A PEEP of 5 cmH2O and a plateau pressure of 16 cmH2O or less were identified as protective mechanical ventilator settings. These findings suggest that protective thresholds differ for intraoperative ventilation in patients with normal lungs compared with those used for patients

  12. Following the surface response of caffeine cocrystals to controlled humidity storage by atomic force microscopy.

    Science.gov (United States)

    Cassidy, A M C; Gardner, C E; Jones, W

    2009-09-08

    Active pharmaceutical ingredient (API) stability in solid state tablet formulation is frequently a function of the relative humidity (RH) environment in which the drug is stored. Caffeine is one such problematic API. Previously reported caffeine cocrystals, however, were found to offer increased resistance to caffeine hydrate formation. Here we report on the use of atomic force microscopy (AFM) to image the surface of two caffeine cocrystal systems to look for differences between the surface and bulk response of the cocrystal to storage in controlled humidity environments. Bulk responses have previously been assessed by powder X-ray diffraction. With AFM, pinning sites were identified at step edges on caffeine/oxalic acid, with these sites leading to non-uniform step movement on going from ambient to 0% RH. At RH >75%, areas of fresh crystal growth were seen on the cocrystal surface. In the case of caffeine/malonic acid the cocrystals were observed to absorb water anisotropically after storage at 75% RH for 2 days, affecting the surface topography of the cocrystal. These results show that AFM expands on the data gathered by bulk analytical techniques, such as powder X-ray diffraction, by providing localised surface information. This surface information may be important for better predicting API stability in isolation and at a solid state API-excipient interface.

  13. Case Report of a Pressure Ulcer Occurring Over the Nasal Bridge Due to a Non-Invasive Ventilation Facial Mask.

    Science.gov (United States)

    Rathore, Farooq A; Ahmad, Faria; Zahoor, Muhammad Umar U

    2016-10-03

    Non-invasive ventilation (NIV) is used in patients with respiratory failure, sleep apnoea, and dyspnoea related to pulmonary oedema. NIV is provided through a facial mask. Many complications of NIV facial masks have been reported, including the breakdown of facial skin. We report a case of an elderly male admitted with multiple co-morbidities. The facial mask was applied continuously for NIV, without any relief or formal monitoring of the underlying skin. It resulted in a Grade II pressure ulcer. We discuss the possible mechanism and offer advice for prevention of such device-related pressure ulcers.

  14. Measurements and prediction of inhaled air quality with personalized ventilation

    DEFF Research Database (Denmark)

    Cermak, Radim; Majer, M.; Melikov, Arsen Krikor

    2002-01-01

    the room air) at flow rates ranging from less than 5 L/s up to 23 L/s. The air quality assessment was based on temperature measurements of the inhaled air and on the portion of the personalized air inhaled. The percentage of dissatisfied with the air quality was predicted. The results suggest......This paper examines the performance of five different air terminal devices for personalized ventilation in relation to the quality of air inhaled by a breathing thermal manikin in a climate chamber. The personalized air was supplied either isothermally or non-isothermally (6 deg.C cooler than...... that regardless of the temperature combinations, personalized ventilation may decrease significantly the number of occupants dissatisfied with the air quality. Under non-isothermal conditions the percentage of dissatisfied may decrease up to 4 times....

  15. Hydrogen storage in thin film magnesium-scandium alloys

    International Nuclear Information System (INIS)

    Niessen, R.A. H.; Notten, P.H. L.

    2005-01-01

    Thorough electrochemical materials research has been performed on thin films of novel magnesium-scandium hydrogen storage alloys. It was found that palladium-capped thin films of Mg x Sc (1-x) with different compositions (ranging from x=0.50 -0.90) show an increase in hydrogen storage capacity of more than 5-20% as compared to their bulk equivalents using even higher discharge rates. The maximum reversible hydrogen storage capacity at the optimal composition (Mg 80 Sc 20 ) amounts to 1795-bar mAh/g corresponding to a hydrogen content of 2.05 H/M or 6.7-bar wt.%, which is close to five times that of the commonly used hydride-forming materials in commercial NiMH batteries. Galvanostatic intermittent titration technique (GITT) measurements show that the equilibrium pressure during discharge is lower than that of bulk powders by one order of magnitude (10 -7 -bar mbar versus 10 -6 -bar mbar, respectively)

  16. Behaviour of Spent WWER fuel under long term storage conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kadarmetov, I M [A.A.Bochvar All-Russia Research Institute of Inorganic Materials, Moscow (Russian Federation)

    1999-07-02

    Results of experimental investigation into thermomechanical properties of pre-irradiated Zr-1%Nb alloy over a range temperatures 500-570 grad C are presented. Safety examination of the Ventilation Storage Casks dry storage system has been carried out. Preliminary safety criteria under dry storage conditions in an environment of inert gas are follows: maximum cladding temperature under normal conditions of dry storage should not exceed 330 grad C after 5-year cooling in water-filled pools; maximum allowable temperature of spent fuel rod cladding under operational mode with infringement of heat removal should not exceed 440 grad C over 8 hours. As each SFA dry storage project comprises its individual technology of spent fuel management, it is necessary to evaluate allowable parameters (terms of storage, maximum temperatures of fuel) for each project respectively. The programme of experimental investigations for the justification of safety criteria for WWER-1000 dry spent fuel storage systems is underway. (author)

  17. Lights and shadows of non-invasive mechanical ventilation for chronic obstructive pulmonary disease (COPD exacerbations

    Directory of Open Access Journals (Sweden)

    Jose Luis Lopez-Campos

    2015-01-01

    Full Text Available Despite the overwhelming evidence justifying the use of non-invasive ventilation (NIV for providing ventilatory support in chronic obstructive pulmonary disease (COPD exacerbations, recent studies demonstrated that its application in real-life settings remains suboptimal. European clinical audits have shown that 1 NIV is not invariably available, 2 its availability depends on countries and hospital sizes, and 3 numerous centers declare their inability to provide NIV to all of the eligible patients presenting throughout the year. Even with an established indication, the use of NIV in acute respiratory failure due to COPD exacerbations faces important challenges. First, the location and personnel using NIV should be carefully selected. Second, the use of NIV is not straightforward despite the availability of technologically advanced ventilators. Third, NIV therapy of critically ill patients requires a thorough knowledge of both respiratory physiology and existing ventilatory devices. Accordingly, an optimal team-training experience, the careful selection of patients, and special attention to the selection of devices are critical for optimizing NIV outcomes. Additionally, when applied, NIV should be closely monitored, and endotracheal intubation should be promptly available in the case of failure. Another topic that merits careful consideration is the use of NIV in the elderly. This patient population is particularly fragile, with several physiological and social characteristics requiring specific attention in relation to NIV. Several other novel indications should also be critically examined, including the use of NIV during fiberoptic bronchoscopy or transesophageal echocardiography, as well as in interventional cardiology and pulmonology. The present narrative review aims to provide updated information on the use of NIV in acute settings to improve the clinical outcomes of patients hospitalized for COPD exacerbations.

  18. Utilization of the organ care system as ex-vivo lung perfusion after cold storage transportation.

    Science.gov (United States)

    Mohite, P N; Maunz, O; Popov, A-F; Zych, B; Patil, N P; Simon, A R

    2015-11-01

    The Organ Care System (OCS) allows perfusion and ventilation of the donor lungs under physiological conditions. Ongoing trials to compare preservation with OCS Lung with standard cold storage do not include donor lungs with suboptimal gas exchange and donor lungs treated with OCS following cold storage transportation. We present a case of a 48-yr-old man who received such lungs after cold storage transportation treated with ex-vivo lung perfusion utilizing OCS. © The Author(s) 2015.

  19. The Effect of Ventilation, Filtration and Passive Sorption on Indoor Air Quality in Museum Storage Rooms

    DEFF Research Database (Denmark)

    Ryhl-Svendsen, M.; Clausen, Geo

    2009-01-01

    in reducing nitrogen dioxide. Increased ventilation rates were expected to dilute internally generated pollutants, but ambiguous results imply that the emission rate of organic acids may also vary Recirculation/filtration was generally, the most efficient method. A cautious conclusion is that a combination...

  20. Why We Ventilate

    Energy Technology Data Exchange (ETDEWEB)

    Logue, Jennifer M.; Sherman, Max H.; Price, Phil N.; Singer, Brett C.

    2011-09-01

    It is widely accepted that ventilation is critical for providing good indoor air quality (IAQ) in homes. However, the definition of"good" IAQ, and the most effective, energy efficient methods for delivering it are still matters of research and debate. This paper presents the results of work done at the Lawrence Berkeley National Lab to identify the air pollutants that drive the need for ventilation as part of a larger effort to develop a health-based ventilation standard. First, we present results of a hazard analysis that identified the pollutants that most commonly reach concentrations in homes that exceed health-based standards or guidelines for chronic or acute exposures. Second, we present results of an impact assessment that identified the air pollutants that cause the most harm to the U.S. population from chronic inhalation in residences. Lastly, we describe the implications of our findings for developing effective ventilation standards.

  1. Design Principles for Natural and Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per

    For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system- Hybrid Ventilation. ....... The hybrid ventilation concepts, design challenges and principles are discussed and illustrated by four building examples.......For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system- Hybrid Ventilation...

  2. Temperature of gas delivered from ventilators.

    Science.gov (United States)

    Chikata, Yusuke; Onodera, Mutsuo; Imanaka, Hideaki; Nishimura, Masaji

    2013-01-01

    Although heated humidifiers (HHs) are the most efficient humidifying device for mechanical ventilation, some HHs do not provide sufficient humidification when the inlet temperature to the water chamber is high. Because portable and home-care ventilators use turbines, blowers, pistons, or compressors to inhale in ambient air, they may have higher gas temperature than ventilators with piping systems. We carried out a bench study to investigate the temperature of gas delivered from portable and home-care ventilators, including the effects of distance from ventilator outlet, fraction of inspiratory oxygen (FIO2), and minute volume (MV). We evaluated five ventilators equipped with turbine, blower, piston, or compressor system. Ambient air temperature was adjusted to 24°C ± 0.5°C, and ventilation was set at FIO2 0.21, 0.6, and 1.0, at MV 5 and 10 L/min. We analyzed gas temperature at 0, 40, 80, and 120 cm from ventilator outlet and altered ventilator settings. While temperature varied according to ventilators, the outlet gas temperature of ventilators became stable after, at the most, 5 h. Gas temperature was 34.3°C ± 3.9°C at the ventilator outlet, 29.5°C ± 2.2°C after 40 cm, 25.4°C ± 1.2°C after 80 cm and 25.1°C ± 1.2°C after 120 cm (P < 0.01). FIO2 and MV did not affect gas temperature. Gas delivered from portable and home-care ventilator was not too hot to induce heated humidifier malfunctioning. Gas soon declined when passing through the limb.

  3. Non-invasive ventilation in the treatment of sleep-related breathing disorders: A review and update

    Directory of Open Access Journals (Sweden)

    A. Nicolini

    2014-11-01

    Full Text Available Non-invasive mechanical ventilation (NIV was originally used in patients with acute respiratory compromises or exacerbations of chronic respiratory diseases as an alternative to intubation. Over the last thirty years NIV has been used during the night in patients with stable chronic lung diseases such as obstructive sleep apnea, the overlap syndrome (COPD and obstructive sleep apnea, neuromuscular disorders, obesity-hypoventilation syndrome and in other conditions such as sleep disorders associated with congestive heart failure.In this review we discuss the different types of NIV, the specific conditions in which they can be used as well as the indications, recommendations, and evidence supporting the efficacy of NIV. Resumo: A ventilação mecânica não invasiva (VNI foi originalmente usada em doentes com insuficiência respiratória aguda ou em exacerbações de doença respiratória crónica, como uma alternativa à intubação. Nos últimos trinta anos, a VNI tem sido usada durante a noite, em doentes com doenças pulmonares crónicas estáveis, como a apneia obstrutiva do sono, a síndrome de sobreposição (DPOC - doença pulmonar obstrutiva crónica - e apneia obstrutiva do sono, disfunções neuromusculares, síndrome de hipoventilação e obesidade, e em outras doenças como os distúrbios do sono associados a insuficiência cardíaca congestiva.Nesta análise discutimos os diferentes tipos de VNI, as condições específicas em que cada um deles pode ser usado, assim como as indicações, recomendações e a evidência que comprova a eficácia da VNI. Keywords: Sleep-related respiratory disorders, Non-invasive ventilation, Continuous positive airway pressure, Bi-level positive airway pressure, Palavras-chave: Distúrbios respiratórios do sono, Ventilação não invasiva, Pressão positiva contínua das vias aéreas, Pressão positiva em dois níveis nas vias aéreas

  4. Pretest Predictions for Ventilation Tests

    International Nuclear Information System (INIS)

    Y. Sun; H. Yang; H.N. Kalia

    2007-01-01

    The objective of this calculation is to predict the temperatures of the ventilating air, waste package surface, concrete pipe walls, and insulation that will be developed during the ventilation tests involving various test conditions. The results will be used as input to the following three areas: (1) Decisions regarding testing set-up and performance. (2) Assessing how best to scale the test phenomena measured. (3) Validating numerical approach for modeling continuous ventilation. The scope of the calculation is to identify the physical mechanisms and parameters related to thermal response in the ventilation tests, and develop and describe numerical methods that can be used to calculate the effects of continuous ventilation. Sensitivity studies to assess the impact of variation of linear power densities (linear heat loads) and ventilation air flow rates are included. The calculation is limited to thermal effect only

  5. Diffuse Ceiling Ventilation

    DEFF Research Database (Denmark)

    Zhang, Chen; Heiselberg, Per; Nielsen, Peter V.

    2014-01-01

    As a novel air distribution system, diffuse ceiling ventilation combines the suspended acoustic ceiling with ventilation supply. Due to the low-impulse supply from the large ceiling area, the system does not generate draught when supplying cold air. However, heat sources play an important role...

  6. Short-term airing by natural ventilation

    DEFF Research Database (Denmark)

    Perino, Marco; Heiselberg, Per

    2009-01-01

    The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. This kind of system frequently integrates traditio......The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. This kind of system frequently integrates...... traditional mechanical ventilation components with natural ventilation devices, such as motorized windows and louvers. Among the various ventilation strategies that are currently available, buoyancy driven single-sided natural ventilation has proved to be very effective and can provide high air change rates...... that was aimed at developing and validating numerical models for the analysis of buoyancy driven single-sided natural ventilation systems. Once validated, these models can be used to optimize control strategies in order to achieve satisfactory indoor comfort conditions and IAQ....

  7. Demand controlled ventilation; Behovsstyrt ventilasjon

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Henning Holm

    2006-07-01

    The terms CAV and VAV have been known terms for many years in the ventilation business. The terms are also included in building regulations, but the time is now right to focus on demand controlled ventilation (DCV). The new building regulations and the accompanying energy framework underline the need for a more nuanced thinking when it comes to controlling ventilation systems. Descriptions and further details of the ventilation systems are provided (ml)

  8. Indoor air quality in mechanically ventilated residential dwellings/low-rise buildings: A review of existing information

    DEFF Research Database (Denmark)

    Aganovic, Amar; Hamon, Mathieu; Kolarik, Jakub

    Mechanical ventilation has become a mandatory requirement in multiple European standards addressing indoor air quality (IAQ) and ventilation in residential dwellings (single family houses and low-rise apartment buildings). This article presents the state of the art study through a review...... of the existing literature, to establish a link between ventilation rate and key indoor air pollutants. Design characteristics of a mechanical ventilation system such as supply/exhaustairflow, system and design of supply and exhaust outlets were considered. The performance of various ventilation solutionswas......-house ventilation rate was reported below 0.5h-1 or 14 l/s·person in bedrooms, the concentrations of the pollutants elevated above minimum threshold limits (CO2>1350 ppm; TVOC >3000 μg/m3) defined by the standard. Insufficient or non-existent supply of air was related to significantly higher pollutant...

  9. Data analysis of ship ventilation ducts based on CATIA V6

    Directory of Open Access Journals (Sweden)

    LU Yongjin

    2017-03-01

    Full Text Available In order to research on CATIA V6 ship duct design and related data,combined with a practical engineering background,a three-dimensional design method for the CATIA V6 ventilation system is exhibited,and the catalog composition of duct fittings and duct lofting process are presented. Meanwhile, revolving around the system design modules,the module processing objects and data storage location are analyzed in order to determine the object of study. And on this basis,the definition and specific content of the engineering technological tables are illustrated in detail;specifically,the contents are extended. Moreover,in light of the three-dimensional model,further research into the underlying data structure of ventilation ducts is implemented. The relationships between the major technological tables are shown. The results of the study are not only beneficial for designers to grasp design technology,but also essential for software developers to secure theoretical guidance and technical support.

  10. Ventilator and viral induced inflammation

    NARCIS (Netherlands)

    Hennus, M.P.

    2013-01-01

    This thesis expands current knowledge on ventilator induced lung injury and provides insights on the immunological effects of mechanical ventilation during viral respiratory infections. The experimental studies in the first part of this thesis improve our understanding of how mechanical ventilation

  11. Mortality of insects and quality of maize grains in hermetic and non-hermetic storage

    Directory of Open Access Journals (Sweden)

    Priscila C. Viebrantz

    2016-05-01

    Full Text Available ABSTRACT Due to the need to improve the quality and safety of foods, chemical methods used to control grain pests have been replaced by alternative methods. For example, modified atmosphere within the storage units has been used. Therefore, the objective was to evaluate maize grain quality and mortality of insects of the species Sitophilus zeamais and Tribolium castaneum in hermetic and non-hermetic environments for 50 days of storage. The hermetic units consisted of polyethylene "bags" with capacity for 60 kg. A cage with 20 adults of each species and 200 g of maize was placed inside each unit. The oxygen level was quantified every five days. Evaluations of insect mortality and survival occurred at 10, 20, 30, 40 and 50 days of storage. At 0, 30 and 50 days, density, moisture and fungal incidence analyses were conducted. The airtight system is efficient in the control of insects, with satisfactory mortality values for both species. Insects favor the development of fungi during the storage, regardless of the storage system.

  12. Thermo-aeraulics of high level waste storage facilities

    International Nuclear Information System (INIS)

    Lagrave, Herve; Gaillard, Jean-Philippe; Laurent, Franck; Ranc, Guillaume; Duret, Bernard

    2006-01-01

    This paper discusses the research undertaken in response to axis 3 of the 1991 radioactive waste management act, and possible solutions concerning the processes under consideration for conditioning and long-term interim storage of long-lived radioactive waste. The notion of 'long-term' is evaluated with respect to the usual operating lifetime of a basic nuclear installation, about 50 years. In this context, 'long-term' is defined on a secular time scale: the lifetime of the facility could be as long as 300 years. The waste package taken into account is characterized notably by its high thermal power release. Studies were carried out in dedicated facilities for vitrified waste and for spent UOX and MOX fuel. The latter are not considered as wastes, owing to the value of the reusable material they contain. Three primary objectives have guided the design of these long-term interim storage facilities: - ensure radionuclide containment at all times; - permit retrieval of the containers at any time; - minimize surveillance; - maintenance costs. The CEA has also investigated surface and subsurface facilities. It was decided to work on generic sites with a reasonable set of parameters values that should be applicable at most sites in France. All the studies and demonstrations to date lead to the conclusion that long-term interim storage is technically feasible. The paper addresses the following items: - Long-term interim storage concepts for high-level waste; - Design principles and options for the interim storage facilities; - General architecture; - Research topics, Storage facility ventilation, Dimensioning of the facility; - Thermo-aeraulics of a surface interim storage facility; - VALIDA surface loop, VALIDA single container test campaign, Continuation of the VALIDA program; - Thermo-aeraulics of a network of subsurface interim storage galleries; - SIGAL subsurface loop; - PROMETHEE subsurface loop; - Temperature behaviour of the concrete structures; - GALATEE

  13. Thermo-aeraulics of high level waste storage facilities

    Energy Technology Data Exchange (ETDEWEB)

    Lagrave, Herve; Gaillard, Jean-Philippe; Laurent, Franck; Ranc, Guillaume [CEA/Valrho, B.P. 17171, F-30207 Bagnols-sur-Ceze (France); Duret, Bernard [CEA Grenoble, 17 rue des Martyrs, 38054 Grenoble cedex 9 (France)

    2006-07-01

    This paper discusses the research undertaken in response to axis 3 of the 1991 radioactive waste management act, and possible solutions concerning the processes under consideration for conditioning and long-term interim storage of long-lived radioactive waste. The notion of 'long-term' is evaluated with respect to the usual operating lifetime of a basic nuclear installation, about 50 years. In this context, 'long-term' is defined on a secular time scale: the lifetime of the facility could be as long as 300 years. The waste package taken into account is characterized notably by its high thermal power release. Studies were carried out in dedicated facilities for vitrified waste and for spent UOX and MOX fuel. The latter are not considered as wastes, owing to the value of the reusable material they contain. Three primary objectives have guided the design of these long-term interim storage facilities: - ensure radionuclide containment at all times; - permit retrieval of the containers at any time; - minimize surveillance; - maintenance costs. The CEA has also investigated surface and subsurface facilities. It was decided to work on generic sites with a reasonable set of parameters values that should be applicable at most sites in France. All the studies and demonstrations to date lead to the conclusion that long-term interim storage is technically feasible. The paper addresses the following items: - Long-term interim storage concepts for high-level waste; - Design principles and options for the interim storage facilities; - General architecture; - Research topics, Storage facility ventilation, Dimensioning of the facility; - Thermo-aeraulics of a surface interim storage facility; - VALIDA surface loop, VALIDA single container test campaign, Continuation of the VALIDA program; - Thermo-aeraulics of a network of subsurface interim storage galleries; - SIGAL subsurface loop; - PROMETHEE subsurface loop; - Temperature behaviour of the concrete

  14. Demand controlled ventilation in a bathroom

    DEFF Research Database (Denmark)

    Mortensen, Dorthe Kragsig; Nielsen, Toke Rammer; Topp, Claus

    2008-01-01

    consumption during periods where the demand for ventilation is low and poor indoor climate during periods where the demand for ventilation is high. Controlling the ventilation rate by demand can improve the energy performance of the ventilation system and the indoor climate. This paper compares the indoor...... climate and energy consumption of a Constant Air Volume (CAV) system and a Demand Controlled Ventilation (DCV) system for two different bathroom designs. The air change rate of the CAV system corresponded to 0.5h-1. The ventilation rate of the DCV system was controlled by occupancy and by the relative...

  15. Melting of “non-magic” argon clusters and extrapolation to the bulk limit

    International Nuclear Information System (INIS)

    Senn, Florian; Wiebke, Jonas; Schumann, Ole; Gohr, Sebastian; Schwerdtfeger, Peter; Pahl, Elke

    2014-01-01

    The melting of argon clusters Ar N is investigated by applying a parallel-tempering Monte Carlo algorithm for all cluster sizes in the range from 55 to 309 atoms. Extrapolation to the bulk gives a melting temperature of 85.9 K in good agreement with the previous value of 88.9 K using only Mackay icosahedral clusters for the extrapolation [E. Pahl, F. Calvo, L. Koči, and P. Schwerdtfeger, “Accurate melting temperatures for neon and argon from ab initio Monte Carlo simulations,” Angew. Chem., Int. Ed. 47, 8207 (2008)]. Our results for argon demonstrate that for the extrapolation to the bulk one does not have to restrict to magic number cluster sizes in order to obtain good estimates for the bulk melting temperature. However, the extrapolation to the bulk remains a problem, especially for the systematic selection of suitable cluster sizes

  16. Realtime mine ventilation simulation

    International Nuclear Information System (INIS)

    McDaniel, K.H.

    1997-01-01

    This paper describes the development of a Windows based, interactive mine ventilation simulation software program at the Waste Isolation Pilot Plant (WIPP). To enhance the operation of the underground ventilation system, Westinghouse Electric Corporation developed the program called WIPPVENT. While WIPPVENT includes most of the functions of the commercially available simulation program VNETPC and uses the same subroutine to calculate airflow distributions, the user interface has been completely rewritten as a Windows application with screen graphics. WIPPVENT is designed to interact with WIPP ventilation monitoring systems through the sitewise Central monitoring System. Data can be continuously collected from the Underground Ventilation Remote Monitoring and Control System (e.g., air quantity and differential pressure) and the Mine Weather Stations (psychrometric data). Furthermore, WIPPVENT incorporates regulator characteristic curves specific to the site. The program utilizes this data to create and continuously update a REAL-TIME ventilation model. This paper discusses the design, key features, and interactive capabilities of WIPPVENT

  17. Styret naturlig ventilation

    DEFF Research Database (Denmark)

    Morsing, S.; Strøm, J.S.

    Publikationen præsenterer et generelt dimensioneringsgrundlag for naturlig ventilation i husdyrstalde. Det er kontrolleret ved forsøg i slagtesvinestalde, hvor det ligeledes er undersøgt hvilken temperaturstabilitet, der kan opnås ved naturlig ventilation, samt produktions- og adfærdsmæssige...

  18. [Evaluation of tidal volume delivered by ventilators during volume-controlled ventilation].

    Science.gov (United States)

    Zhou, Juan; Yan, Yong; Cao, Desen

    2014-12-01

    To study the ways which ensure the delivery of enough tidal volume to patients under various conditions close to the demand of the physician. The volume control ventilation model was chosen, and the simulation lung type was active servo lung ASL 5000 or Michigan lung 1601. The air resistance, air compliance and lung type in simulation lungs were set. The tidal volume was obtained from flow analyzer PF 300. At the same tidal volume, the displaying values of tidal volume of E5, Servo i, Evital 4, and Evital XL ventilators with different lung types of patient, compliance of gas piping, leakage, gas types, etc. were evaluated. With the same setting tidal volume of a same ventilator, the tidal volume delivered to patients was different with different lung types of patient, compliance of gas piping, leakage, gas types, etc. Reducing compliance and increasing resistance of the patient lungs caused high peak airway pressure, the tidal volume was lost in gas piping, and the tidal volume be delivered to the patient lungs was decreased. If the ventilator did not compensate to leakage, the tidal volume delivered to the patient lungs was decreased. When the setting gas type of ventilator did not coincide with that applying to the patient, the tidal volume be delivered to the patient lungs might be different with the setting tidal volume of ventilator. To ensure the delivery of enough tidal volume to patients close to the demand of the physician, containable factors such as the compliance of gas piping, leakage, and gas types should be controlled.

  19. Ventilator associated pneumonia: risk factors and preventive measures.

    Science.gov (United States)

    Vincent, J L; Lobo, S; Struelens, M

    2001-11-01

    Ventilator-associated pneumonia (VAP) is a common nosocomial infection associated with considerable morbidity and mortality. Various risk factors for VAP have been identified and include the duration of ICU stay and of mechanical ventilation, a diagnosis of trauma, and severity of illness. Knowledge of these factors can promote early diagnosis and hence treatment. In addition to simple, but very effective, basic hygiene, different preventative strategies have been suggested, and can be divided into those that aim to limit airway colonization, and those that improve host defense mechanisms. Of the former, non-invasive ventilation is effective but not always applicable or available, nursing the patient in the semi-recumbent position is also associated with a reduced incidence of VAP but carries its own problems, stress ulcer prophylaxis remains controversial, and selective digestive decontamination is probably only relevant to certain subgroups of patients. Methods to improve host defense include early nutrition. Immunostimulatory therapies, such as interferon and granulocyte colony stimulating factor, require further research to confirm their place in the prevention or management of VAP.

  20. Ventilator associated pneumonia among patients on mechanical ventilation at tertiary care centres

    International Nuclear Information System (INIS)

    Rafiq, M.Y.; Ikram, A.; Ayyub, M.

    2018-01-01

    Objective: To determine the frequency of ventilator associated pneumonia (VAP) among patients on mechanical ventilation, and to identify the causative bacterial pathogens and antibiotic susceptibility pattern of isolated microorganisms in intensive care units of tertiary care settings. Study Design: Descriptive cross sectional. Place and Duration of Study: This study was conducted at Microbiology Department, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from Dec 2014 to Aug 2015. Material and Methods: A total of 176 patients on mechanical ventilation were included in the study; patients having respiratory tract infection before putting on ventilator were excluded. Endotracheal aspirate (ETA) and Bronchoalveolar lavage (BAL) samples were collected aseptically from patients on mechanical ventilation on day zero i.e. the day on which the patient was put on ventilator to rule out any previous respiratory tract infection and then after 48 hours to observe the development of VAP. Samples were processed in the laboratory by standard culture techniques, pathogens were identified and their antibiotic susceptibility was performed as per CLSI guidelines. Results: Out of 176 patients on mechanical ventilation, 59 (33.5%) developed VAP. Acinetobacter baumanii being the predominant pathogen isolated from 32 (54.2%) patients followed by MRSA 11 (18.6%), Klebsiella pneumoniae 9 (15.2%), Pseudomonas aeruginosa 5 (8.47%) and Stenotrophomonas maltophila from 2 (3.38%) patients. Conclusion: Frequency of VAP is quite high in our setup, identification of causative bacterial pathogensand their antibiotic susceptibility pattern will not only help in providing effective treatment to the patients but will also help in the formulation of antibiogram according to local resistance patterns for empirical therapy and to reduce the morbidity and mortality. (author)

  1. Studies on the storage of irradiated potatoes

    Energy Technology Data Exchange (ETDEWEB)

    Sharabash, M; Orabi, I O [National Center for research and radiation Technology, Nasr City, Cairo (Egypt); Eloksh, I I; Abd-Alia, M A [Faculty of Agric. Ain Shams University, Cairo (Egypt)

    1995-10-01

    Tubers of alpha and king edward potato cultivars were exposed to O, 10 or 50 krad and stored under room temperature and good ventilation in perforated standard carton boxes. 10 Krad was the promising dosage for sprouting inhibition for both the two cultivars. Total losses in weight were partially dependent on the volume of the dosage, the time elapsed after irradiation and cultivar used. Ascorbic acid slightly decreased, whilst sugar fractions were increased during storage in irradiated tubers. Sugar fractions were sharply decreased in boiled or fried potatoes. Also, chlorogenic acid was increased by prolonging the storage time and/or increasing the exposure dose. After-cooking discoloration (darkening) was reduced by gamma irradiation and/or extending the storage period. Using 0.5% citric acid or 0.5% sodium citrate solution inhibited the after-cooking discoloration. 8 tabs.

  2. Studies on the storage of irradiated potatoes

    International Nuclear Information System (INIS)

    Sharabash, M.; Orabi, I.O.; Eloksh, I.I.; Abd-Alia, M.A.

    1995-01-01

    Tubers of alpha and king edward potato cultivars were exposed to O, 10 or 50 krad and stored under room temperature and good ventilation in perforated standard carton boxes. 10 Krad was the promising dosage for sprouting inhibition for both the two cultivars. Total losses in weight were partially dependent on the volume of the dosage, the time elapsed after irradiation and cultivar used. Ascorbic acid slightly decreased, whilst sugar fractions were increased during storage in irradiated tubers. Sugar fractions were sharply decreased in boiled or fried potatoes. Also, chlorogenic acid was increased by prolonging the storage time and/or increasing the exposure dose. After-cooking discoloration (darkening) was reduced by gamma irradiation and/or extending the storage period. Using 0.5% citric acid or 0.5% sodium citrate solution inhibited the after-cooking discoloration. 8 tabs

  3. Effectiveness of mask ventilation performed by hospital doctors in an Irish tertiary referral teaching hospital.

    LENUS (Irish Health Repository)

    Walsh, K

    2012-02-03

    The objective of this study was to assess the effectiveness of mask ventilation performed by 112 doctors with clinical responsibilities at a tertiary referral teaching hospital. Participant doctors were asked to perform mask ventilation for three minutes on a Resusci Anne mannequin using a facemask and a two litre self inflating bag. The tidal volumes generated were quantified using a Laerdal skillmeter computer as grades 0-5, corresponding to 0, 334, 434, 561, 673 and > 800 ml respectively. The effectiveness of mask ventilation (i.e. the proportion of ventilation attempts which achieved a volume delivery of > 434 mls) was greater for anaesthetists [78.0 (29.5)%] than for non anaesthetists [54.6 (40.0)%] (P = 0.012). Doctors who had attended one or more resuscitation courses where no more effective at mask ventilation than their colleagues who had not undertaken such courses. It is likely that first responders to in-hospital cardiac arrests are commonly unable to perform adequate mask ventilation.

  4. Effect of a ventilator-focused intervention on the rate of Acinetobacter baumannii infection among ventilated patients.

    Science.gov (United States)

    Cohen, Regev; Shimoni, Zvi; Ghara, Riad; Ram, Ron; Ben-Ami, Ronen

    2014-09-01

    Acinetobacter baumannii is a leading cause of ventilator-associated pneumonia, often as a result of ventilator equipment contamination. Evidence-based guidance on optimal care of ventilator equipment to prevent infection is lacking. Here, we report on a significant and persistent reduction in A baumannii infection rates achieved by introducing a strict policy on ventilator care. We implemented an institution-wide ventilator care policy that included routine exchange of breathing circuits and external bacterial filters (every 7-14 days) and replacement followed by routine sterilization of internal bacterial filters (every 4-8 weeks). We analyzed sputum cultures and patient outcomes among ventilated patients before and after the intervention. Between January 2012 and March 2013, 321 patients ventilated for more than 3 days comprised the study cohort. Health care-associated A baumannii acquisition was significantly reduced during the postintervention period (33% vs 16%; odds ratio, 0.39; 95% confidence interval, 0.23-0.67; P = .0008). Additionally, the median time to A baumannii acquisition was significantly longer postintervention (59 vs 21 days; P < .0001). A baumannii ventilator-associated pneumonia risk was also reduced postintervention (odds ratio, 0.39; P = .005). Implementing a stricter standard of ventilator care than that currently defined in published guidelines can significantly decrease health care-associated A baumannii acquisition and related adverse outcomes among ventilated patients. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  5. Neonatal and adult ICU ventilators to provide ventilation in neonates, infants, and children: a bench model study.

    Science.gov (United States)

    Vignaux, Laurence; Piquilloud, Lise; Tourneux, Pierre; Jolliet, Philippe; Rimensberger, Peter C

    2014-10-01

    Using a bench test model, we investigated the hypothesis that neonatal and/or adult ventilators equipped with neonatal/pediatric modes currently do not reliably administer pressure support (PS) in neonatal or pediatric patient groups in either the absence or presence of air leaks. PS was evaluated in 4 neonatal and 6 adult ventilators using a bench model to evaluate triggering, pressurization, and cycling in both the absence and presence of leaks. Delivered tidal volumes were also assessed. Three patients were simulated: a preterm infant (resistance 100 cm H2O/L/s, compliance 2 mL/cm H2O, inspiratory time of the patient [TI] 400 ms, inspiratory effort 1 and 2 cm H2O), a full-term infant (resistance 50 cm H2O/L/s, compliance 5 mL/cm H2O, TI 500 ms, inspiratory effort 2 and 4 cm H2O), and a child (resistance 30 cm H2O/L/s, compliance 10 mL/cm H2O, TI 600 ms, inspiratory effort 5 and 10 cm H2O). Two PS levels were tested (10 and 15 cm H2O) with and without leaks and with and without the leak compensation algorithm activated. Without leaks, only 2 neonatal ventilators and one adult ventilator had trigger delays under a given predefined acceptable limit (1/8 TI). Pressurization showed high variability between ventilators. Most ventilators showed TI in excess high enough to seriously impair patient-ventilator synchronization (> 50% of the TI of the subject). In some ventilators, leaks led to autotriggering and impairment of ventilation performance, but the influence of leaks was generally lower in neonatal ventilators. When a noninvasive ventilation algorithm was available, this was partially corrected. In general, tidal volume was calculated too low by the ventilators in the presence of leaks; the noninvasive ventilation algorithm was able to correct this difference in only 2 adult ventilators. No ventilator performed equally well under all tested conditions for all explored parameters. However, neonatal ventilators tended to perform better in the presence of leaks

  6. Temperature/Humidity Conditions in Stacked Flexible Intermediate Bulk Containers for Shelled Peanuts

    Science.gov (United States)

    Shelled peanuts are loaded into flexible intermediate bulk containers, or totes. After loading, the 1000-kg totes are placed directly into cold storage at 3ºC and 65% relative humidity until shipment to the customer domestically in the United States or internationally requiring transport overseas. ...

  7. Hybrid Ventilation Air Flow Process

    DEFF Research Database (Denmark)

    Heiselberg, Per Kvols

    The scope of this annex is therefore to obtain better knowledge of the use of hybrid ventilation technologies. The annex focus on development of control strategies for hybrid ventilation, on development of methods to predict hybrid ventilation performance in office buildings and on implementation...

  8. The effect of mouth leak and humidification during nasal non-invasive ventilation.

    Science.gov (United States)

    Tuggey, Justin M; Delmastro, Monica; Elliott, Mark W

    2007-09-01

    Poor mask fit and mouth leak are associated with nasal symptoms and poor sleep quality in patients receiving domiciliary non-invasive ventilation (NIV) through a nasal mask. Normal subjects receiving continuous positive airways pressure demonstrate increased nasal resistance following periods of mouth leak. This study explores the effect of mouth leak during pressure-targeted nasal NIV, and whether this results in increased nasal resistance and consequently a reduction in effective ventilatory support. A randomised crossover study of 16 normal subjects was performed on separate days. Comparison was made of the effect of 5 min of mouth leak during daytime nasal NIV with and without heated humidification. Expired tidal volume (V(T)), nasal resistance (R(N)), and patient comfort were measured. Mean change (Delta) in V(T) and R(N) were significantly less following mouth leak with heated humidification compared to the without (DeltaV(T) -36+/-65 ml vs. -88+/-50 ml, phumidification (5.3+/-0.4 vs. 6.2+/-0.4, phumidification. In normal subjects, heated humidification during nasal NIV attenuates the adverse effects of mouth leak on effective tidal volume, nasal resistance and improves overall comfort. Heated humidification should be considered as part of an approach to patients who are troubled with nasal symptoms, once leak has been minimised.

  9. Factors predicting survival in amyotrophic lateral sclerosis patients on non-invasive ventilation.

    Science.gov (United States)

    Gonzalez Calzada, Nuria; Prats Soro, Enric; Mateu Gomez, Lluis; Giro Bulta, Esther; Cordoba Izquierdo, Ana; Povedano Panades, Monica; Dorca Sargatal, Jordi; Farrero Muñoz, Eva

    2016-01-01

    Non invasive ventilation (NIV) improves quality of life and extends survival in amyotrophic lateral sclerosis (ALS) patients. However, few data exist about the factors related to survival. We intended to assess the predictive factors that influence survival in patients after NIV initiation. Patients who started NIV from 2000 to 2014 and were tolerant (compliance ≥ 4 hours) were included; demographic, disease related and respiratory variables at NIV initiation were analysed. Statistical analysis was performed using the Kaplan-Meier test and Cox proportional hazard models. 213 patients were included with median survival from NIV initiation of 13.5 months. In univariate analysis, the identified risk factors for mortality were severity of bulbar involvement (HR 2), Forced Vital Capacity (FVC) % (HR 0.99) and ALSFRS-R (HR 0.97). Multivariate analysis showed that bulbar involvement (HR 1.92) and ALSFRS-R (HR 0.97) were independent predictive factors of survival in patients on NIV. In our study, the two prognostic factors in ALS patients following NIV were the severity of bulbar involvement and ALSFRS-R at the time on NIV initiation. A better assessment of bulbar involvement, including evaluation of the upper airway, and a careful titration on NIV are necessary to optimize treatment efficacy.

  10. Assessment of Natural Ventilation Potential for Residential Buildings across Different Climate Zones in Australia

    Directory of Open Access Journals (Sweden)

    Zijing Tan

    2017-09-01

    Full Text Available In this study, the natural ventilation potential of residential buildings was numerically investigated based on a typical single-story house in the three most populous climate zones in Australia. Simulations using the commercial simulation software TRNSYS (Transient System Simulation Tool were performed for all seasons in three representative cities, i.e., Darwin for the hot humid summer and warm winter zone, Sydney for the mild temperate zone, and Melbourne for the cool temperate zone. A natural ventilation control strategy was generated by the rule-based decision-tree method based on the local climates. Natural ventilation hour (NVH and satisfied natural ventilation hour (SNVH were employed to evaluate the potential of natural ventilation in each city considering local climate and local indoor thermal comfort requirements, respectively. The numerical results revealed that natural ventilation potential was related to the local climate. The greatest natural ventilation potential for the case study building was observed in Darwin with an annual 4141 SNVH out of 4728 NVH, while the least natural ventilation potential was found in the Melbourne case. Moreover, summer and transition seasons (spring and autumn were found to be the optimal periods to sustain indoor thermal comfort by utilising natural ventilation in Sydney and Melbourne. By contrast, natural ventilation was found applicable over the whole year in Darwin. In addition, the indoor operative temperature results demonstrated that indoor thermal comfort can be maintained only by utilising natural ventilation for all cases during the whole year, except for the non-natural ventilation periods in summer in Darwin and winter in Melbourne. These findings could improve the understanding of natural ventilation potential in different climates, and are beneficial for the climate-conscious design of residential buildings in Australia.

  11. Equivalence in Ventilation and Indoor Air Quality

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Max; Walker, Iain; Logue, Jennifer

    2011-08-01

    We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.

  12. Optimization of Ventilation and Alarm Setting During the Process of Ammonia Leak in Refrigeration Machinery Room Based on Numerical Simulation

    Directory of Open Access Journals (Sweden)

    Dongliang Liu

    2017-03-01

    Full Text Available In order to optimize the ventilation effect of ammonia leakage in the refrigeration machinery room, a food processing enterprise is selected as the subject investigated. The velocity and concentration field distribution during the process of ammonia leakage are discussed through simulation of refrigeration machinery room using CFD software. The ventilation system of the room is optimized in three aspects which are named air distribution, ventilation volume and discharge outlet. The influence of the ammonia alarm system through ventilation is also analyzed. The results show that it will be better to set the discharge outlet at the top of the plant than at the side of the wall, and the smaller of the distance between the air outlet and the ammonia gathering area, the better of the effect of ventilation will be. The air flow can be improved and the vortex flow can be reduced if the ventilation volume, the number of air vents and the exhaust velocity are reasonably arranged. Not only the function of the alarm could be ensured, but also the scope of the detection area could be enlarged if the detectors are set on the ceiling of the refrigeration units or the ammonia storage vessel.

  13. Mechanical ventilation and the total artificial heart: optimal ventilator trigger to avoid post-operative autocycling - a case series and literature review

    Directory of Open Access Journals (Sweden)

    Arabia Francisco A

    2010-05-01

    Full Text Available Abstract Many patients with end-stage cardiomyopathy are now being implanted with Total Artificial Hearts (TAHs. We have observed individual cases of post-operative mechanical ventilator autocycling with a flow trigger, and subsequent loss of autocycling after switching to a pressure trigger. These observations prompted us to do a retrospective review of all TAH devices placed at our institution between August 2007 and May 2009. We found that in the immediate post-operative period following TAH placement, autocycling was present in 50% (5/10 of cases. There was immediate cessation of autocycling in all patients after being changed from a flow trigger of 2 L/minute to a pressure trigger of 2 cm H2O. The autocycling group was found to have significantly higher CVP values than the non-autocycling group (P = 0.012. Our data suggest that mechanical ventilator autocycling may be resolved or prevented by the use of a pressure trigger rather than a flow trigger setting in patients with TAHs who require mechanical ventilation.

  14. Synthesis & Studies of New Non-Destructive Read-Out Materials for Optical Storage and Optical Switches

    National Research Council Canada - National Science Library

    Rentzepis, Peter M

    2005-01-01

    .... The optical, chemical and spectroscopic properties of this non-destructive write/read/erase computer memory material have been studied This organic storage system consists of two different molecular...

  15. Boundary conditions for the use of personal ventilation over mixing ventilation in open plan offices

    DEFF Research Database (Denmark)

    Petersen, Steffen; Hviid, Christian Anker

    2013-01-01

    This paper investigates the boundary conditions for choosing a combined Personal Ventilation (PV) and Mixing Ventilation (MV) over conventional mixing ventilation in an office with multiple workers. A simplified procedure for annual performance assessment of PV/MV systems in terms of air quality...

  16. Natural history and risk stratification of patients undergoing non-invasive ventilation in a non-ICU setting for severe COPD exacerbations.

    Science.gov (United States)

    Sainaghi, Pier Paolo; Colombo, Davide; Re, Azzurra; Bellan, Mattia; Sola, Daniele; Balbo, Piero Emilio; Campanini, Mauro; Della Corte, Francesco; Navalesi, Paolo; Pirisi, Mario

    2016-10-01

    Non-invasive ventilation (NIV) delivered in an intensive care unit (ICU) has become the cornerstone in the treatment of patients with severe chronic obstructive pulmonary disease (COPD) exacerbations. A trend towards managing these patients in non-ICU setting has emerged in recent years, although out-of-hospital survival by this approach and how to prognosticate it is unknown. We aimed to investigate these issues. We consecutively recruited 100 patients (49 males; median age 82 years) who received NIV treatment for acute respiratory failure due to COPD exacerbation in non-ICU medical wards of our hospital, between November 2008 and July 2012. We assessed survival (both in-hospital and out-of-hospital) of all these patients, and analyzed baseline parameters in a Cox proportional hazards model to develop a prognostic score. The median survival in the study population was 383 days (240-980). Overall survival rates were 71.0, 65.3, and 52.7 % at 1, 3, and 12 months, respectively. Age >85 years, a history of heart disorders and a neutrophil count ≥10 × 10(9) were associated with higher mortality at Cox's analysis (χ (2) = 35.766, p = 0.0001), and were used to build a prognostic score (NC85). The presence of two or more factors determined the deepest drop in survival (when NC85 ≥2, mortality at 1, 3, and 12 was 60.7, 70.4, and 77.2 %, respectively, while when NC85 = 0 were 4.0, 4.0, and 14.0 %). A simple model, based on three variables (age, neutrophil count and history of heart disease), accurately predicts survival of COPD patients receiving NIV in a non-ICU setting.

  17. A new horizon for the use of non-invasive ventilation in patients with acute respiratory distress syndrome.

    Science.gov (United States)

    Carron, Michele

    2016-09-01

    Non-invasive ventilation (NIV) has assumed an important role in the management of acute respiratory failure (ARF). NIV, compared with standard medical therapy, improves survival and reduces complications in selected patients with ARF. NIV represents the first-line intervention for some forms of ARF, such as chronic obstructive pulmonary disease (COPD) exacerbations and acute cardiogenic pulmonary edema. The use of NIV is also well supported for immunocompromised patients who are at high risk for infectious complications from endotracheal intubation. Selection of appropriate patients is crucial for optimizing NIV success rates. Appropriate ventilator settings, a well-fitting and comfortable interface, and a team skilled and experienced in managing NIV are key components to its success. In a recent issue of the Journal of the American Medical Association , Patel et al . reported the results of their single-center trial of 83 patients with acute respiratory distress syndrome (ARDS) who were randomly assigned to NIV delivered via a helmet or face mask. Patients assigned to the helmet group exhibited a significantly lower intubation rate and were more likely to survive through 90 days. This perspective reviews the findings of this trial in the context of current clinical practice and in light of data from the literature focused on the potential reasons for success of NIV delivered through a helmet compared to face mask. The implications for early management of patients with ARDS are likewise discussed.

  18. 21 CFR 868.5975 - Ventilator tubing.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventilator tubing. 868.5975 Section 868.5975 Food... DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5975 Ventilator tubing. (a) Identification. Ventilator tubing is a device intended for use as a conduit for gases between a ventilator and a patient...

  19. Bulk material engineering and procurement management of NPS

    International Nuclear Information System (INIS)

    Fu Sanhong; Fan Kai

    2005-01-01

    In a nuclear power project, bulk material is often not in an outstanding position, compared to equipment, yet bulk material is one of most difficult part in engineering and procurement management. If the schedule is not in good control, it will seriously hamper the progress of the whole project. The article explores bulk material engineering and procurement management of NPS, illustrated with tables and graphs. First, major difficult aspects of bulk material procurement are described. On one hand, bulk material is really bulky in kind. We must have detail information of manufacturers, manufacture duration, and take good control of bidding schedule. On the other hand, when an order is placed, we need to make clear everything in the procurement package, such as material types, delivery batches, quantity of each batch and delivery schedule, which is a tremendous work. Then, a schedule conflict is analyzed: when an order is placed, the detail type and quantity cannot be defined (since the construction design is not finished yet). To settle this conflict, the concept 'Requirement Schedule Curve' is brought forward, along with the calculation method. To get this curve, we need to make use of the technical data of the reference power station, along with the site construction schedule, to produce a site quantity requirement curve varying from time, for each type of material. Last, based on the 'Requirement Schedule Curve', we are able to build a unified database to control the engineering, procurement, manufacturing and delivery schedule, so as to procure precisely, manufacture on time, and optimize the storage. In this way, the accurate control of bulk material engineering and procurement schedule can be achieved. (authors)

  20. Ventilating Air-Conditioner

    Science.gov (United States)

    Dinh, Khanh

    1994-01-01

    Air-conditioner provides ventilation designed to be used alone or incorporated into cooling or heating system operates efficiently only by recirculating stale air within building. Energy needed to operate overall ventilating cooling or heating system slightly greater than operating nonventilating cooling or heating system. Helps to preserve energy efficiency while satisfying need for increased forced ventilation to prevent accumulation of undesired gases like radon and formaldehyde. Provides fresh treated air to variety of confined spaces: hospital surgeries, laboratories, clean rooms, and printing shops and other places where solvents used. In mobile homes and portable classrooms, eliminates irritant chemicals exuded by carpets, panels, and other materials, ensuring healthy indoor environment for occupants.

  1. Computer-simulation study on fire behaviour in the ventilated cavity of ventilated façade systems

    Directory of Open Access Journals (Sweden)

    Giraldo María P.

    2013-11-01

    Full Text Available Fire spread through the façades is widely recognized as one of the fastest pathways of fire spreading in the buildings. Fire may spread through the façade in different ways depending on the type of façade system and on the elements and materials from which it is constructed. Ventilated façades are multilayer systems whose main feature is the creation of an air chamber of circulating air between the original building wall and the external cladding. The “chimney effect” in the air cavity is a mechanism that improves the façade's thermal behaviour and avoids the appearance of moisture from rain or condensation. However, in a event of fire, it may contribute to the quickest spreading of fire, representing a significant risk to the upper floors of a building. This study deals with some aspects of fire propagation through the ventilated cavity in ventilated façade systems. Also we review the provisions stipulated by the Spanish building code (Código Técnico de la Edificación, CTE [1] to avoid fire spread outside the building. The results highlight the importance of the use of proper fire barriers to ensure the compartmentalization of the ventilated cavity, as well as the use of non-combustible thermal insulation materials, among others. In addition, based on the results, it might be considered that the measures stipulated by the CTE are insufficient to limit the risks associated with this kind of façades systems. The study has been performed using field models of computational fluid-dynamics. In particular, the Fire Dynamics Simulator (FDS software has been used to numerically solve the mathematical integration models.

  2. A preliminary study on the association between ventilation rates in classrooms and student performance.

    Science.gov (United States)

    Shaughnessy, R J; Haverinen-Shaughnessy, U; Nevalainen, A; Moschandreas, D

    2006-12-01

    Poor conditions leading to substandard indoor air quality (IAQ) in classrooms have been frequently cited in the literature over the past two decades. However, there is limited data linking poor IAQ in the classrooms to student performance. Whereas, it is assumed that poor IAQ results in reduced attendance and learning potential, and subsequent poor student performance, validating this hypothesis presents a challenge in today's school environment. This study explores the association between student performance on standardized aptitude tests that are administered to students on a yearly basis, to classroom carbon dioxide (CO2) concentrations, which provide a surrogate of ventilation being provided to each room. Data on classroom CO2 concentrations (over a 4-5 h time span within a typical school day) were recorded in fifth grade classrooms in 54 elementary schools within a school district in the USA. Results from this preliminary study yield a significant (P classroom-level ventilation rate and test results in math. They also indicate that non-linear effects may need to be considered for better representation of the association. A larger sample size is required in order to draw more definitive conclusions. Practical Implications Future studies could focus on (1) gathering more evidence on the possible association between classroom ventilation rates and students' academic performance; (2) the linear/non-linear nature of the association; and (3) whether it is possible to detect 'no observed adverse effect level' for adequate ventilation with respect to academic performance in schools. All of this information could be used to improve guidance and take regulatory actions to ensure adequate ventilation in schools. The high prevalence of low ventilation rates, combined with the growing evidence of the positive impact that sufficient ventilation has on human performance, suggests an opportunity for improving design and management of school facilities.

  3. The role of ventilation. 2 v. Proceedings

    International Nuclear Information System (INIS)

    1994-01-01

    The 78 papers which constitute the proceedings of the conference are presented in two volumes. The papers in the first volume cover sessions dealing with the following broad topics: ventilation strategies; indoor air quality; energy impact of ventilation; building design for optimum ventilation; ventilation and energy. Volume 2 also covers ventilation strategies and ventilation and energy, and in addition: calculation, measurement and design tools; measurement and modelling. Separate abstract have been prepared for 4 papers in Volume 1 which deal with the role of ventilation in mitigating the hazard of radon in buildings. (UK)

  4. Non-invasive mechanical ventilation after the successful weaning: a comparison with the venturi mask

    Directory of Open Access Journals (Sweden)

    Esra Adıyeke

    2016-11-01

    Full Text Available Background and objectives: This study compared the rates of acute respiratory failure, reintubation, length of intensive care stay and mortality in patients in whom the non-invasive mechanical ventilation (NIMV was applied instead of the routine venturi face mask (VM application after a successful weaning. Methods: Following the approval of the hospital ethics committee, 62 patients who were under mechanical ventilation for at least 48 hours were scheduled for this study. 12 patients were excluded because of the weaning failure during T-tube trial. The patients who had optimum weaning criteria after the T-tube trial of 30 minutes were extubated. The patients were kept on VM for 1 hour to observe the hemodynamic and respiratory stability. The group of 50 patients who were successful to wean randomly allocated to have either VM (n = 25, or NIV (n = 25. Systolic arterial pressure (SAP, heart rate (HR, respiratory rate (RR, PaO2, PCO2, and pH values were recorded. Results: The number of patients who developed respiratory failure in the NIV group was significantly less than VM group of patients (3 reintubation vs. 14 NIV + 5 reintubation in the VM group. The length of stay in the ICU was also significantly shorter in NIV group (5.2 ± 4.9 vs. 16.7 ± 7.7 days. Conclusions: The ratio of the respiratory failure and the length of stay in the ICU were lower when non-invasive mechanical ventilation was used after extubation even if the patient is regarded as ‘successfully weaned’. We recommend the use of NIMV in such patients to avoid unexpected ventilator failure. Resumo: Justificativa e objetivos: Este estudo comparou as taxas de insuficiência respiratória aguda, reintubação, tempo de internação em UTI e mortalidade em pacientes sob ventilação mecânica não invasiva (VMNI em vez da habitual máscara facial de Venturi (MV após desmame bem-sucedido. Métodos: Após a aprovação do Comitê de Ética do hospital, 62 pacientes que

  5. Dangerous Pressurization and Inappropriate Alarms during Water Occlusion of the Expiratory Circuit of Commonly Used Infant Ventilators.

    Directory of Open Access Journals (Sweden)

    Murray Hinder

    Full Text Available Non-invasive continuous positive airways pressure is commonly a primary respiratory therapy delivered via multi-purpose ventilators in premature newborns. Expiratory limb occlusion due to water accumulation or 'rainout' from gas humidification is a frequent issue. A case of expiratory limb occlusion due to rainout causing unexpected and excessive repetitive airway pressurisation in a Draeger VN500 prompted a systematic bench test examination of currently available ventilators.To assess neonatal ventilator response to partial or complete expiratory limb occlusion when set to non-invasive continuous positive airway pressure mode.Seven commercially available neonatal ventilators connected to a test lung using a standard infant humidifier circuit with partial and/or complete expiratory limb occlusion were examined in a bench test study. Each ventilator was set to deliver 6 cmH2O in non-invasive mode and respiratory mechanics data for 75%, 80% and 100% occlusion were collected.Several ventilators responded inappropriately with complete occlusion by cyclical pressurisation/depressurisation to peak pressures of between 19·4 and 64·6 cm H2O at rates varying between 2 to 77 inflations per minute. Tidal volumes varied between 10·1 and 24·3mL. Alarm responses varied from 'specific' (tube occluded to 'ambiguous' (Safety valve open. Carefusion Avea responded by continuing to provide the set distending pressure and displaying an appropriate alarm message. Draeger Babylog 8000 did not alarm with partial occlusions and incorrectly displayed airways pressure at 6·1cmH2O compared to the measured values of 13cmH2O.This study found a potential for significant adverse ventilator response due to complete or near complete expiratory limb occlusion in CPAP mode.

  6. Validity of thermally-driven small-scale ventilated filling box models

    Science.gov (United States)

    Partridge, Jamie L.; Linden, P. F.

    2013-11-01

    The majority of previous work studying building ventilation flows at laboratory scale have used saline plumes in water. The production of buoyancy forces using salinity variations in water allows dynamic similarity between the small-scale models and the full-scale flows. However, in some situations, such as including the effects of non-adiabatic boundaries, the use of a thermal plume is desirable. The efficacy of using temperature differences to produce buoyancy-driven flows representing natural ventilation of a building in a small-scale model is examined here, with comparison between previous theoretical and new, heat-based, experiments.

  7. Automated Weaning from Mechanical Ventilation after Off-Pump Coronary Artery Bypass Grafting.

    Science.gov (United States)

    Fot, Evgenia V; Izotova, Natalia N; Yudina, Angelika S; Smetkin, Aleksei A; Kuzkov, Vsevolod V; Kirov, Mikhail Y

    2017-01-01

    workload on medical staff, and does not prolong the duration of weaning from ventilator. The use of automated or protocolized weaning can reduce the duration of postoperative mechanical ventilation in comparison with non-protocolized weaning based on the physician's decision.

  8. Education on invasive mechanical ventilation involving intensive care nurses: a systematic review.

    Science.gov (United States)

    Guilhermino, Michelle C; Inder, Kerry J; Sundin, Deborah

    2018-03-26

    Intensive care unit nurses are critical for managing mechanical ventilation. Continuing education is essential in building and maintaining nurses' knowledge and skills, potentially improving patient outcomes. The aim of this study was to determine whether continuing education programmes on invasive mechanical ventilation involving intensive care unit nurses are effective in improving patient outcomes. Five electronic databases were searched from 2001 to 2016 using keywords such as mechanical ventilation, nursing and education. Inclusion criteria were invasive mechanical ventilation continuing education programmes that involved nurses and measured patient outcomes. Primary outcomes were intensive care unit mortality and in-hospital mortality. Secondary outcomes included hospital and intensive care unit length of stay, length of intubation, failed weaning trials, re-intubation incidence, ventilation-associated pneumonia rate and lung-protective ventilator strategies. Studies were excluded if they excluded nurses, patients were ventilated for less than 24 h, the education content focused on protocol implementation or oral care exclusively or the outcomes were participant satisfaction. Quality was assessed by two reviewers using an education intervention critical appraisal worksheet and a risk of bias assessment tool. Data were extracted independently by two reviewers and analysed narratively due to heterogeneity. Twelve studies met the inclusion criteria for full review: 11 pre- and post-intervention observational and 1 quasi-experimental design. Studies reported statistically significant reductions in hospital length of stay, length of intubation, ventilator-associated pneumonia rates, failed weaning trials and improvements in lung-protective ventilation compliance. Non-statistically significant results were reported for in-hospital and intensive care unit mortality, re-intubation and intensive care unit length of stay. Limited evidence of the effectiveness of

  9. Ventilation of radioactive enclosures; Ventilation des enceintes radioactives

    Energy Technology Data Exchange (ETDEWEB)

    Caminade, F; Laurent, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-07-01

    Mechanical, physical and chemical manipulations on radioactive products must be carried out in properly ventilated enclosed places. The air extracted can only be discharged into the atmosphere after a correct filtration. The power of the ventilation systems is a function of the dimensions and purpose of the enclosure? The choice of types of filter is determined by the physical state and chemical nature of the radioactive materials to be manipulated. This study deals with the individual equipment of small installations: glove boxes, manipulation boxes with outside control and, if necessary, production chambers (maximum useful volume: 5 m{sup 3}). The performances of three types of 'ventilators', and the modifications provided by the addition of filters, are measured and compared. (author) [French] Les manipulations oceaniques, physiques et chimiques sur des produits radioactifs doivent s'effectuer dans des enceintes convenablement ventilees. L'air extrait ne peut etre rejete dans l'atmosphere qu'apres une filtration correcte. La puissance des installations de ventilation est fonction des dimensions de l'enceinte et de son utilisation. Le choix des types de filtres est determine par l'etat physique et la nature ehimique des corps radioactifs manipules. Notre etude porte sur l'equipement individuel d'installations de petites dimensions: boites a gants, boites a pinces et, a la rigueur, enceintes de production (volume maximum utilisable 5 m{sup 3}). Nous mesurons et comparons les performances de trois types de 'ventilateurs' et les modifications apportees par l'adjonction de filtres. (auteur)

  10. How to Plan Ventilation Systems.

    Science.gov (United States)

    Clarke, John H.

    1963-01-01

    Ventilation systems for factory safety demand careful planning. The increased heat loads and new processes of industry have introduced complex ventilation problems in--(1) ventilation supply, (2) duct work design, (3) space requirements, (4) hood face velocities, (5) discharge stacks, and (6) building eddies. This article describes and diagrams…

  11. Thermal Plumes in Ventilated Rooms

    DEFF Research Database (Denmark)

    Kofoed, P.; Nielsen, Peter Vilhelm

    The main objective of ventilation is to provide good air quality for the occupants. For this purpose the necessary ventilating air change rate must be determined. Within displacement ventilation the estimation is closely related to the air flow rate in the thermal plumes when an air quality based...

  12. Randomized, controlled trial comparing synchronized intermittent mandatory ventilation and synchronized intermittent mandatory ventilation plus pressure support in preterm infants.

    Science.gov (United States)

    Reyes, Zenaida C; Claure, Nelson; Tauscher, Markus K; D'Ugard, Carmen; Vanbuskirk, Silvia; Bancalari, Eduardo

    2006-10-01

    Prolonged mechanical ventilation is associated with lung injury in preterm infants. In these infants, weaning from synchronized intermittent mandatory ventilation may be delayed by their inability to cope with increased respiratory loads. The addition of pressure support to synchronized intermittent mandatory ventilation can offset these loads and may facilitate weaning. The purpose of this work was to compare synchronized intermittent mandatory ventilation and synchronized intermittent mandatory ventilation plus pressure support in weaning from mechanical ventilation and the duration of supplemental oxygen dependency in preterm infants with respiratory failure. Preterm infants weighing 500 to 1000 g at birth who required mechanical ventilation during the first postnatal week were randomly assigned to synchronized intermittent mandatory ventilation or synchronized intermittent mandatory ventilation plus pressure support. In both groups, weaning followed a set protocol during the first 28 days. Outcomes were assessed during the first 28 days and until discharge or death. There were 107 infants enrolled (53 synchronized intermittent mandatory ventilation plus pressure support and 54 synchronized intermittent mandatory ventilation). Demographic and perinatal data, mortality, and morbidity did not differ between groups. During the first 28 days, infants in the synchronized intermittent mandatory ventilation plus pressure support group reached minimal ventilator settings and were extubated earlier than infants in the synchronized intermittent mandatory ventilation group. Total duration of mechanical ventilation, duration of oxygen dependency, and oxygen need at 36 weeks' postmenstrual age alone or combined with death did not differ between groups. However, infants in synchronized intermittent mandatory ventilation plus pressure support within the 700- to 1000-g birth weight strata had a shorter oxygen dependency. The results of this study suggest that the addition of

  13. Evaluation of the Use of Capnography during the Transport of Critically Ill Mechanically Ventilated Patients.

    Science.gov (United States)

    1992-12-15

    DISCUSSION: Gervais et a13 demonstrated that respiratory alkalosis developed when ICU patients were manually ventilated, without 7 spirometric...developed a respiratory acidosis. Use of the non-invasive monitor, the capnograph prevented this adverse effect and resulted in inIproved patient safety...ventilation, all patients developed respiratory acidoses. Capnography uniformly prevented the development of respiratory acidosis during transport. We

  14. Subsurface Ventilation System Description Document

    Energy Technology Data Exchange (ETDEWEB)

    Eric Loros

    2001-07-25

    The Subsurface Ventilation System supports the construction and operation of the subsurface repository by providing air for personnel and equipment and temperature control for the underground areas. Although the system is located underground, some equipment and features may be housed or located above ground. The system ventilates the underground by providing ambient air from the surface throughout the subsurface development and emplacement areas. The system provides fresh air for a safe work environment and supports potential retrieval operations by ventilating and cooling emplacement drifts. The system maintains compliance within the limits established for approved air quality standards. The system maintains separate ventilation between the development and waste emplacement areas. The system shall remove a portion of the heat generated by the waste packages during preclosure to support thermal goals. The system provides temperature control by reducing drift temperature to support potential retrieval operations. The ventilation system has the capability to ventilate selected drifts during emplacement and retrieval operations. The Subsurface Facility System is the main interface with the Subsurface Ventilation System. The location of the ducting, seals, filters, fans, emplacement doors, regulators, and electronic controls are within the envelope created by the Ground Control System in the Subsurface Facility System. The Subsurface Ventilation System also interfaces with the Subsurface Electrical System for power, the Monitored Geologic Repository Operations Monitoring and Control System to ensure proper and safe operation, the Safeguards and Security System for access to the emplacement drifts, the Subsurface Fire Protection System for fire safety, the Emplacement Drift System for repository performance, and the Backfill Emplacement and Subsurface Excavation Systems to support ventilation needs.

  15. Subsurface Ventilation System Description Document

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-10-12

    The Subsurface Ventilation System supports the construction and operation of the subsurface repository by providing air for personnel and equipment and temperature control for the underground areas. Although the system is located underground, some equipment and features may be housed or located above ground. The system ventilates the underground by providing ambient air from the surface throughout the subsurface development and emplacement areas. The system provides fresh air for a safe work environment and supports potential retrieval operations by ventilating and cooling emplacement drifts. The system maintains compliance within the limits established for approved air quality standards. The system maintains separate ventilation between the development and waste emplacement areas. The system shall remove a portion of the heat generated by the waste packages during preclosure to support thermal goals. The system provides temperature control by reducing drift temperature to support potential retrieval operations. The ventilation system has the capability to ventilate selected drifts during emplacement and retrieval operations. The Subsurface Facility System is the main interface with the Subsurface Ventilation System. The location of the ducting, seals, filters, fans, emplacement doors, regulators, and electronic controls are within the envelope created by the Ground Control System in the Subsurface Facility System. The Subsurface Ventilation System also interfaces with the Subsurface Electrical System for power, the Monitored Geologic Repository Operations Monitoring and Control System to ensure proper and safe operation, the Safeguards and Security System for access to the emplacement drifts, the Subsurface Fire Protection System for fire safety, the Emplacement Drift System for repository performance, and the Backfill Emplacement and Subsurface Excavation Systems to support ventilation needs.

  16. Intelligent ventilation in the intensive care unit

    Directory of Open Access Journals (Sweden)

    Sigal Sviri

    2012-08-01

    Full Text Available Objectives. Automated, microprocessor-controlled, closed-loop mechanical ventilation has been used in our Medical Intensive Care Unit (MICU at the Hadassah Hebrew-University Medical Center for the past 15 years; for 10 years it has been the primary (preferred ventilator modality. Design and setting. We describe our clinical experience with adaptive support ventilation (ASV over a 6-year period, during which time ASV-enabled ventilators became more readily available and were used as the primary (preferred ventilators for all patients admitted to the MICU. Results. During the study period, 1 220 patients were ventilated in the MICU. Most patients (84% were ventilated with ASV on admission. The median duration of ventilation with ASV was 6 days. The weaning success rate was 81%, and tracheostomy was required in 13%. Sixty-eight patients (6% with severe hypoxia and high inspiratory pressures were placed on pressure-controlled ventilation, in most cases to satisfy a technical requirement for precise and conservative administration of inhaled nitric oxide. The overall pneumothorax rate was less than 3%, and less than 1% of patients who were ventilated only using ASV developed pneumothorax. Conclusions. ASV is a safe and acceptable mode of ventilation for complicated medical patients, with a lower than usual ventilation complication rate.

  17. The Problems of Bulk-Selling Yams in Harvest and Poverty of ...

    African Journals Online (AJOL)

    Simple percentages and frequency tables were used in analyzing the data. Results from this study show that poor storage facilities, poor marketing strategy, problem of income and culture of the people account for the bulk-selling of yams in the study area. The study recommends that there is need for the provision of modern ...

  18. Protective garment ventilation system

    Science.gov (United States)

    Lang, R. (Inventor)

    1970-01-01

    A method and apparatus for ventilating a protective garment, space suit system, and/or pressure suits to maintain a comfortable and nontoxic atmosphere within is described. The direction of flow of a ventilating and purging gas in portions of the garment may be reversed in order to compensate for changes in environment and activity of the wearer. The entire flow of the ventilating gas can also be directed first to the helmet associated with the garment.

  19. Non-invasive ventilation in amyotrophic lateral sclerosis: a 10 year population based study.

    Science.gov (United States)

    Chiò, Adriano; Calvo, Andrea; Moglia, Cristina; Gamna, Federica; Mattei, Alessio; Mazzini, Letizia; Mora, Gabriele

    2012-04-01

    To evaluate the clinical characteristics and outcome of non-invasive ventilation (NIV) in an epidemiological based series of amyotrophic lateral sclerosis (ALS) patients. The study was performed using data from the Piemonte and Valle d'Aosta Register for ALS, a prospective epidemiological register enrolling all ALS incident cases in two Italian regions. Among the 1260 patients incident in the period 1995-2004, 259 (20.6%) underwent NIV. Young male patients and subjects attending the tertiary ALS centres were more likely to undergo NIV. There was a progressive significant increase in the use of NIV during the study but was limited to patients attending the ALS tertiary centres. Median survival after NIV was 289 days (95% CI 255 to 333). In an epidemiological setting, NIV represents an increasingly utilised option for the treatment of respiratory disturbances in ALS and has favourable effects on survival, in particular among patients followed by tertiary ALS centres. Sociocultural factors, such as age, gender and marital status, strongly influence the probability of undergoing NIV. Efforts should be made to remove these obstacles in order to spread the use of NIV in all ALS patients with respiratory failure.

  20. 46 CFR 153.312 - Ventilation system standards.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Ventilation system standards. 153.312 Section 153.312... Handling Space Ventilation § 153.312 Ventilation system standards. A cargo handling space ventilation system must meet the following: (a) A ventilation system exhaust duct must discharge no less than 10 m...

  1. Reusable Areas of Clinically Used Ventilators Carry Low Numbers of Aerobic Bacteria

    Directory of Open Access Journals (Sweden)

    Elizabeth Anne Gonzalez

    2014-12-01

    Full Text Available Ventilator associated pneumonia (VAP remains a serious problem for critically ill patients. We swabbed nine reusable areas on 20 clinically-used ventilators from a VA Hospital shortly after they had been removed from patients and identified bacterial isolates. No bacteria were isolated from most of the samples and of the samples that did grow bacteria, the majority of those had fewer than 10 colonies. The bacteria that were isolated were primarily non-pathogenic Gram-positive skin flora. Of the 20 ventilators swabbed, only one cultured bacteria associated with nosocomial infections: methicillin-resistant S.aureus. The most commonly contaminated areas were those most likely to be touched by healthcare professionals: the power button and the screen. The areas in closest proximity to the patients, the inspiratory and expiratory ports were the least often contaminated areas. Overall, very few bacteria were transferred to the reusable areas of the ventilators following clinical use.

  2. Reusable Areas of Clinically Used Ventilators Carry Low Numbers of Aerobic Bacteria

    Directory of Open Access Journals (Sweden)

    Elizabeth Anne Gonzalez

    2014-10-01

    Full Text Available Ventilator associated pneumonia (VAP remains a serious problem for critically ill patients. We swabbed nine reusable areas on 20 clinically-used ventilators from a VA Hospital shortly after they had been removed from patients and identified bacterial isolates. No bacteria were isolated from most of the samples and of the samples that did grow bacteria, the majority of those had fewer than 10 colonies. The bacteria that were isolated were primarily non-pathogenic Gram-positive skin flora. Of the 20 ventilators swabbed, only one cultured bacteria associated with nosocomial infections: methicillin-resistant S.aureus. The most commonly contaminated areas were those most likely to be touched by healthcare professionals: the power button and the screen. The areas in closest proximity to the patients, the inspiratory and expiratory ports were the least often contaminated areas. Overall, very few bacteria were transferred to the reusable areas of the ventilators following clinical use.

  3. Design of Energy Efficient Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per

    The focus in the development has for both systems been to minimise energy consumption while maintaining a comfortable and healthy indoor environment. The natural next step in this development is to develop ventilation concepts that utilises and combines the best features from each system......[Mechanical and natural ventilation] into a new type of ventilation system- Hybrid Ventilation....

  4. Efficiency of Noninvasive Ventilation in Acute Heart Failure

    Directory of Open Access Journals (Sweden)

    Z. Z. Nadiradze

    2008-01-01

    Full Text Available Objective: to evaluate the efficiency of noninvasive supporting ventilation in patients with acute cardiorespiratory failure in the early postoperative period after cardiac surgery under extracorporeal circulation. Methods. Case histories of patients operated on the heart under extracorporeal circulation, who postoperatively developed acute car-diorespiratory failure requiring repeated artificial ventilation (AV, were retrospectively studied. According to the AV mode, the patients were divided into 2 groups. Non-invasive AV was carried out in Group 1 (a study group. In Group 2 (a control group, tracheal intubation and mechanical ventilation were performed when respiratory indices deteriorated. In both groups, anesthesia was maintained without deviating from the clinically accepted protocol. The indications for extubation were routine. Following 24—72 hours after extubation, the health status of patients became worse, as manifested in decreased circulatory performance, requiring that they be switched to AV. Clinical and laboratory findings were used to define indications for AV switching. The conditions for noninvasive ventilation were the close cooperation of a patient with medical personnel, the absence of significant hyperthermia, injury, operation or facial abnormally, which excluded intimate mating. Results. Analysis of gas exchange changes suggests that there are no differences between the groups both just after surgery and within 24 postperfusion hours after extubation. When the condition deteriorated, no differences in oxygen exchange and delivery were observed in the study and control groups. In the control group, PaO2, oxygenation index, and oxygen delivery index were significantly less than those in the study group. Analysis of the duration of assisted ventilation revealed that the study group patients were on a respirator significantly less than the controls. The length of intensive care unit stay also increased greatly in Group 2

  5. Ventilation system design for educational facilities

    Energy Technology Data Exchange (ETDEWEB)

    Elsafty, A.F.; Abo Elazm, M.M. [Arab Academy for Science, Alexandria (Egypt). Technology and Maritime Transport; Safwan, M. [Arab Academy for Science, Cairo (Egypt). Technology and Maritime Transport

    2010-07-01

    In order to maintain acceptable indoor air quality levels in classrooms, high ventilation rates are needed to dilute the concentration of indoor contaminants, resulting in higher energy consumption for the operation of mechanical ventilation systems. Three factors are usually considered when determining the adequate ventilation rate for classrooms in educational facilities. These include the maximum population served in the classroom; carbon dioxide (CO{sub 2}) production rate by occupants; and outdoor air conditions. CO{sub 2} concentrations usually indicate the rate of ventilation required. This paper presented a newly developed computer software program for determining the ventilation rates needed to enhance indoor air quality and to maintain CO{sub 2} concentration within the recommended levels by ANSI/ASHRAE standards for best student performance. This paper also presented design curves for determining the ventilation rates and air changes per hour required for the ventilated educational zone. 15 refs., 2 tabs., 5 figs.

  6. Long-term non-invasive ventilation reduces readmissions in COPD patients with two or more episodes of acute hypercapnic respiratory failure

    DEFF Research Database (Denmark)

    Ankjærgaard, Kasper Linde; Maibom, Sophia Liff; Wilcke, Jon Torgny

    2016-01-01

    BACKGROUND: Chronic obstructive pulmonary disease (COPD) patients who have had an episode of acute hypercapnic respiratory failure (AHRF) have a large 1-year risk of death or readmission. Acute non-invasive ventilation (NIV) has been shown to be an effective treatment of AHRF; and long-term NIV.......88 (p=0.0092). Four patients (20%) died in 1 year. LTNIV tended to reduce arterial CO2. No changes were found in lung function. CONCLUSIONS: LTNIV seems effective in reducing recurrent AHRF and readmissions in a highly select group of patients with severe, unstable COPD and frequent AHRF....

  7. Understanding mechanical ventilators.

    Science.gov (United States)

    Chatburn, Robert L

    2010-12-01

    The respiratory care academic community has not yet adopted a standardized system for classifying and describing modes of ventilation. As a result, there is enough confusion that patient care, clinician education and even ventilator sales are all put at risk. This article summarizes a ventilator mode taxonomy that has been extensively published over the last 15 years. Specifically, the classification system has three components: a description of the control variables within breath; a description of the sequence of mandatory and spontaneous breaths; and a specification for the targeting scheme. This three-level specification provides scalability of detail to make the mode description appropriate for the particular need. At the bedside, we need only refer to a mode briefly using the first or perhaps first and second components. To distinguish between similar modes and brand names, we would need to include all components. This taxonomy uses the equation of motion for the respiratory system as the underlying theoretical framework. All terms relevant to describing modes of mechanical ventilation are defined in an extensive appendix.

  8. Improved regression models for ventilation estimation based on chest and abdomen movements

    International Nuclear Information System (INIS)

    Liu, Shaopeng; Gao, Robert; He, Qingbo; Staudenmayer, John; Freedson, Patty

    2012-01-01

    Non-invasive estimation of minute ventilation is important for quantifying the intensity of physical activity of individuals. In this paper, several improved regression models are presented, based on the measurement of chest and abdomen movements from sensor belts worn by subjects (n = 50) engaged in 14 types of physical activity. Five linear models involving a combination of 11 features were developed, and the effects of different model training approaches and window sizes for computing the features were investigated. The performance of the models was evaluated using experimental data collected during the physical activity protocol. The predicted minute ventilation was compared to the criterion ventilation measured using a bidirectional digital volume transducer housed in a respiratory gas exchange system. The results indicate that the inclusion of breathing frequency and the use of percentile points instead of interdecile ranges over a 60 s window size reduced error by about 43%, when applied to the classical two-degrees-of-freedom model. The mean percentage error of the minute ventilation estimated for all the activities was below 7.5%, verifying reasonably good performance of the models and the applicability of the wearable sensing system for minute ventilation estimation during physical activity. (paper)

  9. SU-F-J-219: Predicting Ventilation Change Due to Radiation Therapy: Dependency On Pre-RT Ventilation and Effort Correction

    Energy Technology Data Exchange (ETDEWEB)

    Patton, T; Du, K; Bayouth, J [University of Wisconsin, Madison, WI (United States); Christensen, G; Reinhardt, J [University of Iowa, Iowa City, IA (United States)

    2016-06-15

    Purpose: Ventilation change caused by radiation therapy (RT) can be predicted using four-dimensional computed tomography (4DCT) and image registration. This study tested the dependency of predicted post-RT ventilation on effort correction and pre-RT lung function. Methods: Pre-RT and 3 month post-RT 4DCT images were obtained for 13 patients. The 4DCT images were used to create ventilation maps using a deformable image registration based Jacobian expansion calculation. The post-RT ventilation maps were predicted in four different ways using the dose delivered, pre-RT ventilation, and effort correction. The pre-RT ventilation and effort correction were toggled to determine dependency. The four different predicted ventilation maps were compared to the post-RT ventilation map calculated from image registration to establish the best prediction method. Gamma pass rates were used to compare the different maps with the criteria of 2mm distance-to-agreement and 6% ventilation difference. Paired t-tests of gamma pass rates were used to determine significant differences between the maps. Additional gamma pass rates were calculated using only voxels receiving over 20 Gy. Results: The predicted post-RT ventilation maps were in agreement with the actual post-RT maps in the following percentage of voxels averaged over all subjects: 71% with pre-RT ventilation and effort correction, 69% with no pre-RT ventilation and effort correction, 60% with pre-RT ventilation and no effort correction, and 58% with no pre-RT ventilation and no effort correction. When analyzing only voxels receiving over 20 Gy, the gamma pass rates were respectively 74%, 69%, 65%, and 55%. The prediction including both pre- RT ventilation and effort correction was the only prediction with significant improvement over using no prediction (p<0.02). Conclusion: Post-RT ventilation is best predicted using both pre-RT ventilation and effort correction. This is the only prediction that provided a significant

  10. Psychological as well as illness factors influence acceptance of non-invasive ventilation (NIV) and gastrostomy in amyotrophic lateral sclerosis (ALS):A prospective population study

    OpenAIRE

    Martin, Naomi H; Landau, Sabine; Janssen, Anna; Lyall, Rebecca; Higginson, Irene; Burman, Rachel; McCrone, Paul; Sakel, Mohammed; Ellis, Catherine M; Shaw, Christopher E; Al-Chalabi, Ammar; Leigh, P Nigel; Goldstein, Laura H

    2014-01-01

    Our objective was to identify factors associated with acceptance of non-invasive ventilation (NIV) and gastrostomy in an exploratory population-based study. Seventy-eight people with ALS at least six months post-diagnosis, and 50 caregivers, were recruited from the South-East ALS Register. Baseline physical, cognitive and psychological measures were obtained. Three-monthly follow-ups monitored whether patients had accepted or refused NIV or gastrostomy. Following an intervention decision, pos...

  11. The impact of a ventilator bundle on preventing ventilator-associated pneumonia: a multicenter study.

    Science.gov (United States)

    Eom, Joong Sik; Lee, Mi-Suk; Chun, Hee-Kyung; Choi, Hee Jung; Jung, Sun-Young; Kim, Yeon-Sook; Yoon, Seon Jin; Kwak, Yee Gyung; Oh, Gang-Bok; Jeon, Min-Hyok; Park, Sun-Young; Koo, Hyun-Sook; Ju, Young-Su; Lee, Jin Seo

    2014-01-01

    For prevention of ventilator-associated pneumonia (VAP), a bundle approach was applied to patients receiving mechanical ventilation in intensive care units. The incidence of VAP and the preventive efficacy of the VAP bundle were investigated. A quasi-experimental study was conducted in adult intensive care units of 6 university hospitals with similar VAP rates. We implemented the VAP bundle between March 2011 and June 2011, then compared the rate of VAP after implementation of the VAP bundle with the rate in the previous 8 months. Our ventilator bundle included head of bed elevation, peptic ulcer disease prophylaxis, deep venous thrombosis prophylaxis, and oral decontamination with chlorhexidine 0.12%. Continuous aspiration of subglottic secretions was an option. Implementation of the VAP bundle reduced the VAP rate from a mean of 4.08 cases per 1,000 ventilator-days to 1.16 cases per 1,000 ventilator-days. The incidence density ratio (rate) was 0.28 (95% confidence interval, 0.275-0.292). Implementing the appropriate VAP bundle significantly decreased the incidence of VAP in patients with mechanical ventilation. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  12. Activation of the Wnt/β-catenin signaling pathway by mechanical ventilation is associated with ventilator-induced pulmonary fibrosis in healthy lungs.

    Directory of Open Access Journals (Sweden)

    Jesús Villar

    Full Text Available BACKGROUND: Mechanical ventilation (MV with high tidal volumes (V(T can cause or aggravate lung damage, so-called ventilator induced lung injury (VILI. The relationship between specific mechanical events in the lung and the cellular responses that result in VILI remains incomplete. Since activation of Wnt/β-catenin signaling has been suggested to be central to mechanisms of lung healing and fibrosis, we hypothesized that the Wnt/β-catenin signaling plays a role during VILI. METHODOLOGY/PRINCIPAL FINDINGS: Prospective, randomized, controlled animal study using adult, healthy, male Sprague-Dawley rats. Animals (n = 6/group were randomized to spontaneous breathing or two strategies of MV for 4 hours: low tidal volume (V(T (6 mL/kg or high V(T (20 mL/kg. Histological evaluation of lung tissue, measurements of WNT5A, total β-catenin, non-phospho (Ser33/37/Thr41 β-catenin, matrix metalloproteinase-7 (MMP-7, cyclin D1, vascular endothelial growth factor (VEGF, and axis inhibition protein 2 (AXIN2 protein levels by Western blot, and WNT5A, non-phospho (Ser33/37/Thr41 β-catenin, MMP-7, and AXIN2 immunohistochemical localization in the lungs were analyzed. High-V(T MV caused lung inflammation and perivascular edema with cellular infiltrates and collagen deposition. Protein levels of WNT5A, non-phospho (Ser33/37/Thr41 β-catenin, MMP-7, cyclin D1, VEGF, and AXIN2 in the lungs were increased in all ventilated animals although high-V(T MV was associated with significantly higher levels of WNT5A, non-phospho (Ser33/37/Thr41 β-catenin, MMP-7, cyclin D1, VEGF, and AXIN2 levels. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate that the Wnt/β-catenin signaling pathway is modulated very early by MV in lungs without preexistent lung disease, suggesting that activation of this pathway could play an important role in both VILI and lung repair. Modulation of this pathway might represent a therapeutic option for prevention and/or management of VILI.

  13. Ventilation rates and health

    DEFF Research Database (Denmark)

    Sundell, Jan; Levin, H; Nazaroff, W W

    2011-01-01

    and health effects to inform the relationship. Consistency was found across multiple investigations and different epidemiologic designs for different populations. Multiple health endpoints show similar relationships with ventilation rate. There is biological plausibility for an association of health outcomes...... studies of the relationship between ventilation rates and health, especially in diverse climates, in locations with polluted outdoor air and in buildings other than offices. PRACTICAL IMPLICATIONS: Ventilation with outdoor air plays an important role influencing human exposures to indoor pollutants...

  14. Methodology for ventilation/perfusion SPECT

    DEFF Research Database (Denmark)

    Bajc, Marika; Neilly, Brian; Miniati, Massimo

    2010-01-01

    radiolabeled liquid aerosols are not restricted to the presence of obstructive lung disease. Radiolabeled macroaggregated human albumin is the imaging agent of choice for perfusion scintigraphy. An optimal combination of nuclide activities and acquisition times for ventilation and perfusion, collimators......Ventilation/perfusion single-photon emission computed tomography (V/Q SPECT) is the scintigraphic technique of choice for the diagnosis of pulmonary embolism and many other disorders that affect lung function. Data from recent ventilation studies show that the theoretic advantages of Technegas over......, and imaging matrix yields an adequate V/Q SPECT study in approximately 20 minutes of imaging time. The recommended protocol based on the patient remaining in an unchanged position during the initial ventilation study and the perfusion study allows presentation of matching ventilation and perfusion slices...

  15. A multiscale MDCT image-based breathing lung model with time-varying regional ventilation

    Science.gov (United States)

    Yin, Youbing; Choi, Jiwoong; Hoffman, Eric A.; Tawhai, Merryn H.; Lin, Ching-Long

    2012-01-01

    A novel algorithm is presented that links local structural variables (regional ventilation and deforming central airways) to global function (total lung volume) in the lung over three imaged lung volumes, to derive a breathing lung model for computational fluid dynamics simulation. The algorithm constitutes the core of an integrative, image-based computational framework for subject-specific simulation of the breathing lung. For the first time, the algorithm is applied to three multi-detector row computed tomography (MDCT) volumetric lung images of the same individual. A key technique in linking global and local variables over multiple images is an in-house mass-preserving image registration method. Throughout breathing cycles, cubic interpolation is employed to ensure C1 continuity in constructing time-varying regional ventilation at the whole lung level, flow rate fractions exiting the terminal airways, and airway deformation. The imaged exit airway flow rate fractions are derived from regional ventilation with the aid of a three-dimensional (3D) and one-dimensional (1D) coupled airway tree that connects the airways to the alveolar tissue. An in-house parallel large-eddy simulation (LES) technique is adopted to capture turbulent-transitional-laminar flows in both normal and deep breathing conditions. The results obtained by the proposed algorithm when using three lung volume images are compared with those using only one or two volume images. The three-volume-based lung model produces physiologically-consistent time-varying pressure and ventilation distribution. The one-volume-based lung model under-predicts pressure drop and yields un-physiological lobar ventilation. The two-volume-based model can account for airway deformation and non-uniform regional ventilation to some extent, but does not capture the non-linear features of the lung. PMID:23794749

  16. A multiscale MDCT image-based breathing lung model with time-varying regional ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Youbing, E-mail: youbing-yin@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Department of Radiology, The University of Iowa, Iowa City, IA 52242 (United States); Choi, Jiwoong, E-mail: jiwoong-choi@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Hoffman, Eric A., E-mail: eric-hoffman@uiowa.edu [Department of Radiology, The University of Iowa, Iowa City, IA 52242 (United States); Department of Biomedical Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Department of Internal Medicine, The University of Iowa, Iowa City, IA 52242 (United States); Tawhai, Merryn H., E-mail: m.tawhai@auckland.ac.nz [Auckland Bioengineering Institute, The University of Auckland, Auckland (New Zealand); Lin, Ching-Long, E-mail: ching-long-lin@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States)

    2013-07-01

    A novel algorithm is presented that links local structural variables (regional ventilation and deforming central airways) to global function (total lung volume) in the lung over three imaged lung volumes, to derive a breathing lung model for computational fluid dynamics simulation. The algorithm constitutes the core of an integrative, image-based computational framework for subject-specific simulation of the breathing lung. For the first time, the algorithm is applied to three multi-detector row computed tomography (MDCT) volumetric lung images of the same individual. A key technique in linking global and local variables over multiple images is an in-house mass-preserving image registration method. Throughout breathing cycles, cubic interpolation is employed to ensure C{sub 1} continuity in constructing time-varying regional ventilation at the whole lung level, flow rate fractions exiting the terminal airways, and airway deformation. The imaged exit airway flow rate fractions are derived from regional ventilation with the aid of a three-dimensional (3D) and one-dimensional (1D) coupled airway tree that connects the airways to the alveolar tissue. An in-house parallel large-eddy simulation (LES) technique is adopted to capture turbulent-transitional-laminar flows in both normal and deep breathing conditions. The results obtained by the proposed algorithm when using three lung volume images are compared with those using only one or two volume images. The three-volume-based lung model produces physiologically-consistent time-varying pressure and ventilation distribution. The one-volume-based lung model under-predicts pressure drop and yields un-physiological lobar ventilation. The two-volume-based model can account for airway deformation and non-uniform regional ventilation to some extent, but does not capture the non-linear features of the lung.

  17. Assisted Ventilation in Patients with Acute Respiratory Distress Syndrome: Lung-distending Pressure and Patient-Ventilator Interaction

    NARCIS (Netherlands)

    Doorduin, J.; Sinderby, C.A.; Beck, J.; Hoeven, J.G. van der; Heunks, L.M.

    2015-01-01

    BACKGROUND: In patients with acute respiratory distress syndrome (ARDS), the use of assisted mechanical ventilation is a subject of debate. Assisted ventilation has benefits over controlled ventilation, such as preserved diaphragm function and improved oxygenation. Therefore, higher level of

  18. Energy Storage Needs in Interconnected Systems Using the Example of Germany and Austria

    Directory of Open Access Journals (Sweden)

    Thomas Weiss

    2014-09-01

    Full Text Available The share of renewable energies on the net electricity consumption is rising steadily. Especially intermittent, non-controllable sources like wind and sun are gaining importance. With an installed amount of non-controllable power that exceeds the yearly peak load, situations can occur with a surplus of energy in electricity supply systems. This surplus will rise strongly with the share of fluctuating renewable energies on the net electricity consumption. A lot of studies and experts come to the conclusion that energy storage will be needed to handle these surpluses. The questions that still have to be answered are when and how. Especially the German electricity system will have very high storage needs because of a very strong and fast development of wind and solar power. There are a lot of technologies and approaches to overcome this problem. However, Pumped Hydro Energy Storage (PHES systems are up to date the most efficient and economic bulk energy storage technology. On the one side there are no high potentials in natural sites for the installation of PHES schemes in Germany. On the other side the Austrian PHES system has still a very high potential. Up so far, the prospects are used just to a small amount. Especially the seasonal Hydro Energy Storage (HES still holds a very high potential. In this paper the combination of the Austrian and the German energy supply system will be investigated with respect to the development of renewable energies. The overall energy storage needs are evaluated for each country as well as in the combined system, taking also into account the development and the influence of the transmission system capacity between the two countries.

  19. TS LOOP ALCOVE VENTILATION ANALYSIS

    International Nuclear Information System (INIS)

    T.M. Lahnalampi

    2000-01-01

    The scope of this analysis is to examine the existing, constructor installed, physical ventilation installations located in each of the Exploratory Studies Facility (ESF) Topopah Springs (TS) Loop Alcoves No.1, No.2, No.3, No.4, No.6, and No.7. Alcove No.5 is excluded from the scope of this analysis since it is an A/E design system. Each ventilation installation will be analyzed for the purpose of determining if requirements for acceptance into the A/E design technical baseline have been met. The ventilation installations will be evaluated using Occupational Safety and Health Administration (OSHA) standards and Exploratory Studies Facility Design Requirements (ESFDR) (YMP 1997) requirements. The end product will be a technical analysis that will define ventilation installation compliance issues, any outstanding field changes, and use-as-is design deviations that are required to bring the ventilation installations into compliance with requirements for acceptance into the A/E design technical baseline. The analysis will provide guidance for alcove ventilation component design modifications to be developed to correct any deficient components that do not meet minimum requirements and standards

  20. Mechanical ventilation for severe asthma.

    Science.gov (United States)

    Leatherman, James

    2015-06-01

    Acute exacerbations of asthma can lead to respiratory failure requiring ventilatory assistance. Noninvasive ventilation may prevent the need for endotracheal intubation in selected patients. For patients who are intubated and undergo mechanical ventilation, a strategy that prioritizes avoidance of ventilator-related complications over correction of hypercapnia was first proposed 30 years ago and has become the preferred approach. Excessive pulmonary hyperinflation is a major cause of hypotension and barotrauma. An appreciation of the key determinants of hyperinflation is essential to rational ventilator management. Standard therapy for patients with asthma undergoing mechanical ventilation consists of inhaled bronchodilators, corticosteroids, and drugs used to facilitate controlled hypoventilation. Nonconventional interventions such as heliox, general anesthesia, bronchoscopy, and extracorporeal life support have also been advocated for patients with fulminant asthma but are rarely necessary. Immediate mortality for patients who are mechanically ventilated for acute severe asthma is very low and is often associated with out-of-hospital cardiorespiratory arrest before intubation. However, patients who have been intubated for severe asthma are at increased risk for death from subsequent exacerbations and must be managed accordingly in the outpatient setting.

  1. Wind Extraction for Natural Ventilation

    Science.gov (United States)

    Fagundes, Tadeu; Yaghoobian, Neda; Kumar, Rajan; Ordonez, Juan

    2017-11-01

    Due to the depletion of energy resources and the environmental impact of pollution and unsustainable energy resources, energy consumption has become one of the main concerns in our rapidly growing world. Natural ventilation, a traditional method to remove anthropogenic and solar heat gains, proved to be a cost-effective, alternative method to mechanical ventilation. However, while natural ventilation is simple in theory, its detailed design can be a challenge, particularly for wind-driven ventilation, which its performance highly involves the buildings' form, surrounding topography, turbulent flow characteristics, and climate. One of the main challenges with wind-driven natural ventilation schemes is due to the turbulent and unpredictable nature of the wind around the building that impose complex pressure loads on the structure. In practice, these challenges have resulted in founding the natural ventilation mainly on buoyancy (rather than the wind), as the primary force. This study is the initial step for investigating the physical principals of wind extraction over building walls and investigating strategies to reduce the dependence of the wind extraction on the incoming flow characteristics and the target building form.

  2. Intravesical prostatic protrusion correlates well with storage symptoms in elderly male patients with non-neurogenic overactive bladder

    Directory of Open Access Journals (Sweden)

    Shih-Yen Lu

    2016-03-01

    Conclusion: In elderly male patients with non-neurogenic OAB, more severe storage symptoms are associated with a lower maximum flow rate and a more prominent IPP, indicating that a significant cause of male non-neurogenic OAB is prostate associated.

  3. Thermal comfort of seated occupants in rooms with personalized ventilation combined with mixing or displacement ventilation

    DEFF Research Database (Denmark)

    Forejt, L.; Melikov, Arsen Krikor; Cermak, Radim

    2004-01-01

    The performance of two personalized ventilation systems combined with mixing or displacement ventilation was studied under different conditions in regard to thermal comfort of seated occupants. The cooling performance of personalized ventilation was found to be independent of room air distribution...

  4. Low tidal volume ventilation ameliorates left ventricular dysfunction in mechanically ventilated rats following LPS-induced lung injury.

    Science.gov (United States)

    Cherpanath, Thomas G V; Smeding, Lonneke; Hirsch, Alexander; Lagrand, Wim K; Schultz, Marcus J; Groeneveld, A B Johan

    2015-10-07

    High tidal volume ventilation has shown to cause ventilator-induced lung injury (VILI), possibly contributing to concomitant extrapulmonary organ dysfunction. The present study examined whether left ventricular (LV) function is dependent on tidal volume size and whether this effect is augmented during lipopolysaccharide(LPS)-induced lung injury. Twenty male Wistar rats were sedated, paralyzed and then randomized in four groups receiving mechanical ventilation with tidal volumes of 6 ml/kg or 19 ml/kg with or without intrapulmonary administration of LPS. A conductance catheter was placed in the left ventricle to generate pressure-volume loops, which were also obtained within a few seconds of vena cava occlusion to obtain relatively load-independent LV systolic and diastolic function parameters. The end-systolic elastance / effective arterial elastance (Ees/Ea) ratio was used as the primary parameter of LV systolic function with the end-diastolic elastance (Eed) as primary LV diastolic function. Ees/Ea decreased over time in rats receiving LPS (p = 0.045) and high tidal volume ventilation (p = 0.007), with a lower Ees/Ea in the rats with high tidal volume ventilation plus LPS compared to the other groups (p tidal volume ventilation without LPS (p = 0.223). A significant interaction (p tidal ventilation and LPS for Ees/Ea and Eed, and all rats receiving high tidal volume ventilation plus LPS died before the end of the experiment. Low tidal volume ventilation ameliorated LV systolic and diastolic dysfunction while preventing death following LPS-induced lung injury in mechanically ventilated rats. Our data advocates the use of low tidal volumes, not only to avoid VILI, but to avert ventilator-induced myocardial dysfunction as well.

  5. Lung-protective ventilation in abdominal surgery.

    Science.gov (United States)

    Futier, Emmanuel; Jaber, Samir

    2014-08-01

    To provide the most recent and relevant clinical evidence regarding the use of prophylactic lung-protective mechanical ventilation in abdominal surgery. Evidence is accumulating, suggesting an association between intraoperative mechanical ventilation strategy and postoperative pulmonary complications in patients undergoing abdominal surgery. Nonprotective ventilator settings, especially high tidal volume (>10-12 ml/kg), very low level of positive end-expiratory pressure (PEEP, ventilator-associated lung injury in patients with healthy lungs. Stimulated by the previous findings in patients with acute respiratory distress syndrome, the use of lower tidal volume ventilation is becoming increasingly more common in the operating room. However, lowering tidal volume, though important, is only part of the overall multifaceted approach of lung-protective mechanical ventilation. Recent data provide compelling evidence that prophylactic lung-protective mechanical ventilation using lower tidal volume (6-8 ml/kg of predicted body weight), moderate PEEP (6-8 cm H2O), and recruitment maneuvers is associated with improved functional or physiological and clinical postoperative outcome in patients undergoing abdominal surgery. The use of prophylactic lung-protective ventilation can help in improving the postoperative outcome.

  6. New modes of assisted mechanical ventilation.

    Science.gov (United States)

    Suarez-Sipmann, F

    2014-05-01

    Recent major advances in mechanical ventilation have resulted in new exciting modes of assisted ventilation. Compared to traditional ventilation modes such as assisted-controlled ventilation or pressure support ventilation, these new modes offer a number of physiological advantages derived from the improved patient control over the ventilator. By implementing advanced closed-loop control systems and using information on lung mechanics, respiratory muscle function and respiratory drive, these modes are specifically designed to improve patient-ventilator synchrony and reduce the work of breathing. Depending on their specific operational characteristics, these modes can assist spontaneous breathing efforts synchronically in time and magnitude, adapt to changing patient demands, implement automated weaning protocols, and introduce a more physiological variability in the breathing pattern. Clinicians have now the possibility to individualize and optimize ventilatory assistance during the complex transition from fully controlled to spontaneous assisted ventilation. The growing evidence of the physiological and clinical benefits of these new modes is favoring their progressive introduction into clinical practice. Future clinical trials should improve our understanding of these modes and help determine whether the claimed benefits result in better outcomes. Copyright © 2013 Elsevier España, S.L. and SEMICYUC. All rights reserved.

  7. Ventilation systems as air cleaning devices in nuclear power plants: experience at Palisades

    International Nuclear Information System (INIS)

    Sullivan, T.J.; Murri, E.L.

    1975-01-01

    Experience at Palisades has demonstrated the importance of designing, constructing, testing and operating the ventilation system from the viewpoint of airborne radioactivity control during both normal operation and anticipated operational occurrences. An item of particular concern was the difficulty in maintaining correct non-ducted airflow patterns. Inadequate preoperational testing and system balancing led to marginal ventilation system performance. This condition was further aggravated by extensive plant maintenance and construction activities and, in some cases, by a lack of administrative control. Following completion of construction of the radwaste addition, it was possible, with minor basic design changes, to adjust and rebalance the entire ventilation system, thus assuring control of airborne radioactivity. (U.S.)

  8. Weaning from non-invasive positive pressure ventilation: Experience with progressive periods of withdraw

    Directory of Open Access Journals (Sweden)

    C. Damas

    2008-01-01

    Full Text Available Background: In recent years non-invasive ventilation (NIV as become a valuable therapeutic option in exacerbations of patients with chronic pulmonary obstructive disease. Although widely used there is a paucity of information on weaning from NIV. Objectives: We aimed to describe the performance of a weaning protocol based on progressive periods of NIV withdraw. Methods: During a one year period we performed NIV in 78 patients with acute exacerbation of chronic respiratory failure. Weaning was considered in patients with 24 hours without acidosis and respiratory rate less than 25 cycles per minute. Weaning was performed as following: during the first 24 hours in each 3 hours, one hour without NIV (except during night period, in the second day in each 3 hours, two hours without NIV (except during night period and in the third day NIV was used during the night period. Results: Sixty five patients began the weaning protocol. Mean NIV time was 120,9 hours (17 to 192 hours. No adverse effects were recorded in patients who began the weaning protocol. All patients completed the weaning protocol with no re-institution of NIV or invasive ventilation during hospitalization. Conclusions: We report an excellent weaning success rate of NIV in patients with acute severe exacerbation of CRF. Although our weaning protocol required 72 hours, our results suggest that strategies based on periods with and with-out NIV are effective. Weather similar less time consuming weaning strategies are effective, merits investigation. Resumo: Introdução: Nos últimos anos, a ventilação não invasiva (VNI tornou-se numa opção terapêutica válida nas exacerbações agudas de doentes com doença pulmonar crónica obstrutiva. No entanto, apesar de muito utilizada, existe muito pouca informação sobre o desmame deste modo ventilatório. Objectivos: Descrever um protocolo de desmame baseado em períodos progressivos de descontinuação de VNI. Métodos: Durante um ano foram

  9. Design Principles for Natural and Hybrid Ventilation

    OpenAIRE

    Heiselberg, Per

    2000-01-01

    For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system- Hybrid Ventilation. The hybrid ventilation concepts, design challenges and principles are discussed and illustrated by four building examples.

  10. Ventilation effectiveness : health benefits of heat recovery ventilators

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2010-08-15

    Studies have shown that the installation of a heat recovery ventilator (HRV) in homes in northern Canada could improve indoor air quality and the respiratory health of inhabitants. Low ventilation rates are common in many homes in the North because the climate is severe, homes are smaller and lack basements, and occupancies are higher, leading to unhealthy indoor air quality. Northern communities also have a high rate of respiratory infections. HRVs recover much of the energy used to ventilate, which is desirable in cold regions with high heating costs. For the study, the test sample was divided into two types of houses, notably houses with active HRVs and those with control HRVs that were installed and operated but that did not function. The study results showed that HRVs provided increased ventilation. Complaints by residents about HRV noise, discomfort, or low humidity were common but equally spread between those with active and placebo HRVs. The study showed that the system design needs to be improved to better suit the needs of Inuit families. The nature of northern housing presents installation and maintenance challenges. It is hard to retrofit HRV ducting inside small, existing houses, and building supplies arrive infrequently, so detailed planning and careful take-offs of all supplies and materials must be done well in advance of construction. In addition, contractors are hard to locate and have variable expertise, and there is little technical follow-up. Robust technical support by local contractors and housing authorities is therefore important. 2 refs.

  11. Prevention of ventilator-associated pneumonia

    Directory of Open Access Journals (Sweden)

    J. Oliveira

    2014-05-01

    Full Text Available Invasive mechanical ventilation (IMV represents a risk factor for the development of ventilator-associated pneumonia (VAP, which develops at least 48 h after admission in patients ventilated through tracheostomy or endotracheal intubation. VAP is the most frequent intensive-care-unit (ICU-acquired infection among patients receiving IMV. It contributes to an increase in hospital mortality, duration of MV and ICU and length of hospital stay. Therefore, it worsens the condition of the critical patient and increases the total cost of hospitalization. The introduction of preventive measures has become imperative, to ensure control and to reduce the incidence of VAP. Preventive measures focus on modifiable risk factors, mediated by non-pharmacological and pharmacological evidence based strategies recommended by guidelines. These measures are intended to reduce the risk associated with endotracheal intubation and to prevent microaspiration of pathogens to the lower airways. Resumo: A ventilação mecânica invasiva representa um fator de risco para o desenvolvimento da pneumonia associada ao ventilador (PAV, que se desenvolve 48 horas ou mais após a admissão hospitalar, em doentes ventilados através de traqueostomia ou intubação endotraqueal. A PAV é a infeção adquirida na unidade de cuidados intensivos (UCI mais frequente entre os doentes submetidos a ventilação mecânica invasiva. Contribui para o aumento da mortalidade hospitalar, da duração da ventilação mecânica e do tempo de internamento na UCI e no hospital. Por conseguinte, agrava o estado de saúde do doente crítico e aumenta o custo total da hospitalização. A adoção de medidas preventivas é imprescindível, de modo a garantir o controlo e a diminuição da incidência da PAV. As medidas preventivas incidem sobre os fatores de risco modificáveis, sendo aplicadas estratégias não farmacológicas e farmacológicas baseadas na evidência e recomendadas por guidelines. As

  12. Weaning newborn infants from mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Paolo Biban

    2013-06-01

    Full Text Available Invasive mechanical ventilation is a life-saving procedure which is largely used in neonatal intensive care units, particularly in very premature newborn infants. However, this essential treatment may increase mortality and cause substantial morbidity, including lung or airway injuries, unplanned extubations, adverse hemodynamic effects, analgosedative dependency and severe infectious complications, such as ventilator-associated pneumonia. Therefore, limiting the duration of airway intubation and mechanical ventilator support is crucial for the neonatologist, who should aim to a shorter process of discontinuing mechanical ventilation as well as an earlier appreciation of readiness for spontaneous breathing trials. Unfortunately, there is scarce information about the best ways to perform an effective weaning process in infants undergoing mechanical ventilation, thus in most cases the weaning course is still based upon the individual judgment of the attending clinician. Nonetheless, some evidence indicate that volume targeted ventilation modes are more effective in reducing the duration of mechanical ventilation than traditional pressure limited ventilation modes, particularly in very preterm babies. Weaning and extubation directly from high frequency ventilation could be another option, even though its effectiveness, when compared to switching and subsequent weaning and extubating from conventional ventilation, is yet to be adequately investigated. Some data suggest the use of weaning protocols could reduce the weaning time and duration of mechanical ventilation, but better designed prospective studies are still needed to confirm these preliminary observations. Finally, the implementation of short spontaneous breathing tests in preterm infants has been shown to be beneficial in some centres, favoring an earlier extubation at higher ventilatory settings compared with historical controls, without worsening the extubation failure rate. Further

  13. Local cooling of the human body using ventilated matress in hospitals

    DEFF Research Database (Denmark)

    Bivolarova, Mariya Petrova; Melikov, Arsen Krikor; Kokora, Monika

    2014-01-01

    A series of experiments were conducted in order to examine the cooling of the human body in bed equipped with a ventilated mattress (VM). The experiments were performed in a climate chamber (4.65 m width x 5.3 m length x 2.6 m height) which was air-conditioned by mixing ventilation system...... temperature or by use of natural ventilation. However the non-uniform body cooling may cause local thermal discomfort. This needs to be further studied in human subject experiments......., 26 and 30 oC. The performance of the VM was tested when VM was operating at different air flow rates (1.5, 3, 4.5 and 6 L/s). The impact of body covering on the cooling effect from the VM was also studied. The performance of the cooling method was evaluated based on comparison of the segmental...

  14. A Porcine Model for Initial Surge Mechanical Ventilator Assessment and Evaluation of Two Limited Function Ventilators

    Science.gov (United States)

    Dickson, Robert P; Hotchkin, David L; Lamm, Wayne JE; Hinkson, Carl; Pierson, David J; Glenny, Robb W; Rubinson, Lewis

    2013-01-01

    Objective To adapt an animal model of acute lung injury for use as a standard protocol for a screening, initial evaluation of limited function, or “surge,” ventilators for use in mass casualty scenarios. Design Prospective, experimental animal study. Setting University research laboratory. Subjects 12 adult pigs. Interventions 12 spontaneously breathing pigs (6 in each group) were subjected to acute lung injury/acute respiratory distress syndrome (ALI/ARDS) via pulmonary artery infusion of oleic acid. Following development of respiratory failure, animals were mechanically ventilated with a limited function ventilator (Simplified Automatic Ventilator [SAVe] I or II; Automedx) for one hour or until the ventilator could not support the animal. The limited function ventilator was then exchanged for a full function ventilator (Servo 900C; Siemens). Measurements and Main Results Reliable and reproducible levels of ALI/ARDS were induced. The SAVe I was unable to adequately oxygenate 5 animals, with PaO2 (52.0 ± 11.1 torr) compared to the Servo (106.0 ± 25.6 torr; p=0.002). The SAVe II was able to oxygenate and ventilate all 6 animals for one hour with no difference in PaO2 (141.8 ± 169.3 torr) compared to the Servo (158.3 ± 167.7 torr). Conclusions We describe a novel in vivo model of ALI/ARDS that can be used to initially screen limited function ventilators considered for mass respiratory failure stockpiles, and is intended to be combined with additional studies to defintively assess appropriateness for mass respiratory failure. Specifically, during this study we demonstrate that the SAVe I ventilator is unable to provide sufficient gas exchange, while the SAVe II, with several more functions, was able to support the same level of hypoxemic respiratory failure secondary to ALI/ARDS for one hour. PMID:21187747

  15. Ventilation Inception and Washout, Scaling, and Effects on Hydrodynamic Performance of a Surface Piercing Strut

    Science.gov (United States)

    Harwood, Casey; Young, Yin Lu; Ceccio, Steven

    2014-11-01

    High-lift devices that operate at or near a fluid free surface (such as surface-piercing or shallowly-submerged propellers and hydrofoils) are prone to a multiphase flow phenomenon called ventilation, wherein non-condensable gas is entrained in the low-pressure flow, forming a cavity around the body and dramatically altering the global hydrodynamic forces. Experiments are being conducted at the University of Michigan's towing tank using a canonical surface-piercing strut to investigate atmospheric ventilation. The goals of the work are (i) to gain an understanding of the dominant physics in fully wetted, partially ventilated, and fully ventilated flow regimes, (ii) to quantify the effects of governing dimensionless parameters on the transition between flow regimes, and (iii) to develop scaling relations for the transition between flow regimes. Using theoretical arguments and flow visualization techniques, new criteria are developed for classifying flow regimes and transition mechanisms. Unsteady transition mechanisms are described and mapped as functions of the governing non-dimensional parameters. A theoretical scaling relationship is developed for ventilation washout, which is shown to adequately capture the experimentally-observed washout boundary. This material is based upon work supported by the National Science Foundation Graduate Student Research Fellowship under Grant No. DGE 1256260. Support also comes from the Naval Engineering Education Center (Award No. N65540-10-C-003).

  16. Comparison between conventional protective mechanical ventilation and high-frequency oscillatory ventilation associated with the prone position.

    Science.gov (United States)

    Fioretto, José Roberto; Klefens, Susiane Oliveira; Pires, Rafaelle Fernandes; Kurokawa, Cilmery Suemi; Carpi, Mario Ferreira; Bonatto, Rossano César; Moraes, Marcos Aurélio; Ronchi, Carlos Fernando

    2017-01-01

    To compare the effects of high-frequency oscillatory ventilation and conventional protective mechanical ventilation associated with the prone position on oxygenation, histology and pulmonary oxidative damage in an experimental model of acute lung injury. Forty-five rabbits with tracheostomy and vascular access were underwent mechanical ventilation. Acute lung injury was induced by tracheal infusion of warm saline. Three experimental groups were formed: healthy animals + conventional protective mechanical ventilation, supine position (Control Group; n = 15); animals with acute lung injury + conventional protective mechanical ventilation, prone position (CMVG; n = 15); and animals with acute lung injury + high-frequency oscillatory ventilation, prone position (HFOG; n = 15). Ten minutes after the beginning of the specific ventilation of each group, arterial gasometry was collected, with this timepoint being called time zero, after which the animal was placed in prone position and remained in this position for 4 hours. Oxidative stress was evaluated by the total antioxidant performance assay. Pulmonary tissue injury was determined by histopathological score. The level of significance was 5%. Both groups with acute lung injury showed worsening of oxygenation after induction of injury compared with the Control Group. After 4 hours, there was a significant improvement in oxygenation in the HFOG group compared with CMVG. Analysis of total antioxidant performance in plasma showed greater protection in HFOG. HFOG had a lower histopathological lesion score in lung tissue than CMVG. High-frequency oscillatory ventilation, associated with prone position, improves oxygenation and attenuates oxidative damage and histopathological lung injury compared with conventional protective mechanical ventilation.

  17. Protective ventilation of preterm lambs exposed to acute chorioamnionitis does not reduce ventilation-induced lung or brain injury.

    Science.gov (United States)

    Barton, Samantha K; Moss, Timothy J M; Hooper, Stuart B; Crossley, Kelly J; Gill, Andrew W; Kluckow, Martin; Zahra, Valerie; Wong, Flora Y; Pichler, Gerhard; Galinsky, Robert; Miller, Suzanne L; Tolcos, Mary; Polglase, Graeme R

    2014-01-01

    The onset of mechanical ventilation is a critical time for the initiation of cerebral white matter (WM) injury in preterm neonates, particularly if they are inadvertently exposed to high tidal volumes (VT) in the delivery room. Protective ventilation strategies at birth reduce ventilation-induced lung and brain inflammation and injury, however its efficacy in a compromised newborn is not known. Chorioamnionitis is a common antecedent of preterm birth, and increases the risk and severity of WM injury. We investigated the effects of high VT ventilation, after chorioamnionitis, on preterm lung and WM inflammation and injury, and whether a protective ventilation strategy could mitigate the response. Pregnant ewes (n = 18) received intra-amniotic lipopolysaccharide (LPS) 2 days before delivery, instrumentation and ventilation at 127±1 days gestation. Lambs were either immediately euthanased and used as unventilated controls (LPSUVC; n = 6), or were ventilated using an injurious high VT strategy (LPSINJ; n = 5) or a protective ventilation strategy (LPSPROT; n = 7) for a total of 90 min. Mean arterial pressure, heart rate and cerebral haemodynamics and oxygenation were measured continuously. Lungs and brains underwent molecular and histological assessment of inflammation and injury. LPSINJ lambs had poorer oxygenation than LPSPROT lambs. Ventilation requirements and cardiopulmonary and systemic haemodynamics were not different between ventilation strategies. Compared to unventilated lambs, LPSINJ and LPSPROT lambs had increases in pro-inflammatory cytokine expression within the lungs and brain, and increased astrogliosis (pVentilation after acute chorioamnionitis, irrespective of strategy used, increases haemodynamic instability and lung and cerebral inflammation and injury. Mechanical ventilation is a potential contributor to WM injury in infants exposed to chorioamnionitis.

  18. Use of non-contacting electromagnetic inductive method for estimating soil moisture across a landscape

    International Nuclear Information System (INIS)

    Khakural, B.R.; Robert, P.C.; Hugins, D.R.

    1998-01-01

    There is a growing interest in real-time estimation of soil moisture for site-specific crop management. Non-contacting electromagnetic inductive (EMI) methods have potentials to provide real-time estimate of soil profile water contents. Soil profile water contents were monitored with a neutron probe at selected sites. A Geonics LTD EM-38 terrain meter was used to record bulk soil electrical conductivity (EC(A)) readings across a soil-landscape in West central Minnesota with variable moisture regimes. The relationships among EC(A), selected soil and landscape properties were examined. Bulk soil electrical conductivity (0-1.0 and 0-0.5 m) was negatively correlated with relative elevation. It was positively correlated with soil profile (1.0 m) clay content and negatively correlated with soil profile coarse fragments (2 mm) and sand content. There was significant linear relationship between ECA (0-1.0 and 0-0.5) and soil profile water storage. Soil water storage estimated from ECA reflected changes in landscape and soil characteristics

  19. Color stability of bulk-fill and incremental-fill resin-based composites polished with aluminum-oxide impregnated disks

    Directory of Open Access Journals (Sweden)

    Uzay Koc-Vural

    2017-05-01

    Full Text Available Objectives This study aimed to evaluate the color stability of bulk-fill and nanohybrid resin-based composites polished with 3 different, multistep, aluminum-oxide impregnated finishing and polishing disks. Materials and Methods Disk-shaped specimens (8 mm in diameter and 4 mm in thickness were light-cured between two glass slabs using one nanohybid bulk-fill (Tetric EvoCeram, Ivoclar Vivadent, one micro-hybrid bulk-fill (Quixfil, Dentsply, and two nanohybrid incremental-fill (Filtek Ultimate, 3M ESPE; Herculite XRV Ultra, Kerr resin-based composites, and aged by thermocycling (between 5 - 55℃, 3,000 cycles. Then, they were divided into subgroups according to the polishing procedure as SwissFlex (Coltène/Whaledent, Optidisc (Kerr, and Praxis TDV (TDV Dental (n = 12 per subgroup. One surface of each specimen was left unpolished. All specimens were immersed in coffee solution at 37℃. The color differences (ΔE were measured after 1 and 7 days of storage using a colorimeter based on CIE Lab system. The data were analyzed by univariate ANOVA, Mann-Whitney U test, and Friedmann tests (α = 0.05. Results Univariate ANOVA detected significant interactions between polishing procedure and composite resin and polishing procedure and storage time (p 0.05. Polishing reduced the discoloration resistance of Tetric EvoCeram/SwissFlex, Tetric EvoCeram/Praxis TDV, Quixfil-SwissFlex, and all Herculite XRV Ultra groups after 7 days storage (p < 0.05. Conclusions Discoloration resistance of bulk-fill resin-based composites can be significantly affected by the polishing procedures.

  20. Storage facility for highly radioactive solid waste

    International Nuclear Information System (INIS)

    Kitano, Shozo

    1996-01-01

    A heat insulation plate is disposed at an intermediate portion between a ceiling wall of a storage chamber and an upper plate of a storage pit in parallel with them. A large number of highly radioactive solid wastes contained in canisters are contained in the storage pit. Cooling air is introduced from an air suction port, passes a channel on the upper side of the heat insulation plate formed by the ceiling of the storage chamber and the heat insulation plate, and flows from a flow channel on the side of the wall of the storage chamber to the lower portion of the storage pit. Afterheat is removed by the air flown from the lower portion to ventilation tubes at the outer side of container tubes. The air heated to a high temperature through the flow channel on the lower side of the heat insulation plate between the heat insulation plate and the upper plate of the storage pit, and is exhausted to an exhaustion port. Further, a portion of a heat insulation plate as a boundary between the cooling air and a high temperature air formed on the upper portion of the storage pit is formed as a heat transfer plate, so that the heat of the high temperature air is removed by the cooling air flowing the upper flow channel. This can prevent heating of the ceiling wall of the storage chamber. (I.N.)