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Sample records for pressure-controlled ventilation pcv

  1. Ventilation of Nonparalyzed Patients Under Anesthesia with Laryngeal Mask Airway, Comparison of Three Modes of Ventilation: Volume Controlled Ventilation, Pressure Controlled Ventilation, and Pressure Controlled Ventilation-volume Guarantee

    PubMed Central

    Ghabach, Maroun Badwi; El Hajj, Elie M.; El Dib, Rouba D.; Rkaiby, Jeanette M.; Matta, May S.; Helou, May R.

    2017-01-01

    Background: Pressure controlled ventilation (PCV) is the preferable mode of ventilation of nonparalyzed patients undergoing anesthesia with laryngeal mask airway (LMA) as compared to volume controlled ventilation (VCV) and spontaneously breathing patient. In this study, we compared the PC–volume guarantee (PC-VG) mode of ventilation with VCV and PCV modes. Materials and Methods: A total of 30 patients, American Society of Anesthesiologists (ASA) physical status Classes I and II, scheduled for elective surgery under general anesthesia with a classic LMA were ventilated, subsequently, with the three modes of ventilation: VCV, PCV, and PC-VG for 10 min each mode. Tidal volume set for all patients was 8 ml/kg of ideal body weight. Parameters measured with modes of ventilation include peak inspiratory pressure (PIP), compliance, measured tidal volume, O2 saturation, end-tidal CO2, and presence of an oropharyngeal leak. Results: The PIP was significantly higher with the application of VCV mode of ventilation than PCV and PC-VG modes. The compliance was significantly lower when using the mode of ventilation VCV than PCV and PC-VG. The PIP and the compliance were not statistically different between the PCV and PC-VG modes of ventilation. Conclusions: Ventilation of nonparalyzed patients with LMA under anesthesia with PC-VG is advantageous over VCV in reducing PIP and increasing lung compliance. No difference was noted between PCV and PC-VG in ASA Classes I or II under the adequate depth of anesthesia in patients with normal pulmonary function. PMID:28298784

  2. Model-based setting of inspiratory pressure and respiratory rate in pressure-controlled ventilation.

    PubMed

    Schranz, C; Becher, T; Schädler, D; Weiler, N; Möller, K

    2014-03-01

    Mechanical ventilation carries the risk of ventilator-induced-lung-injury (VILI). To minimize the risk of VILI, ventilator settings should be adapted to the individual patient properties. Mathematical models of respiratory mechanics are able to capture the individual physiological condition and can be used to derive personalized ventilator settings. This paper presents model-based calculations of inspiration pressure (pI), inspiration and expiration time (tI, tE) in pressure-controlled ventilation (PCV) and a retrospective evaluation of its results in a group of mechanically ventilated patients. Incorporating the identified first order model of respiratory mechanics in the basic equation of alveolar ventilation yielded a nonlinear relation between ventilation parameters during PCV. Given this patient-specific relation, optimized settings in terms of minimal pI and adequate tE can be obtained. We then retrospectively analyzed data from 16 ICU patients with mixed pathologies, whose ventilation had been previously optimized by ICU physicians with the goal of minimization of inspiration pressure, and compared the algorithm's 'optimized' settings to the settings that had been chosen by the physicians. The presented algorithm visualizes the patient-specific relations between inspiration pressure and inspiration time. The algorithm's calculated results highly correlate to the physician's ventilation settings with r = 0.975 for the inspiration pressure, and r = 0.902 for the inspiration time. The nonlinear patient-specific relations of ventilation parameters become transparent and support the determination of individualized ventilator settings according to therapeutic goals. Thus, the algorithm is feasible for a variety of ventilated ICU patients and has the potential of improving lung-protective ventilation by minimizing inspiratory pressures and by helping to avoid the build-up of clinically significant intrinsic positive end-expiratory pressure.

  3. Comparison of volume controlled ventilation and pressure controlled ventilation in patients undergoing robot-assisted pelvic surgeries: An open-label trial

    PubMed Central

    Jaju, Rishabh; Jaju, Pooja Bihani; Dubey, Mamta; Mohammad, Sadik; Bhargava, AK

    2017-01-01

    Background and Aims: Although volume controlled ventilation (VCV) has been the traditional mode of ventilation in robotic surgery, recently pressure controlled ventilation (PCV) has been used more frequently. However, evidence on whether PCV is superior to VCV is still lacking. We intended to compare the effects of VCV and PCV on respiratory mechanics and haemodynamic in patients undergoing robotic surgeries in steep Trendelenburg position. Methods: This prospective, randomized trial was conducted on sixty patients between 20 and 70 years belonging to the American Society of Anesthesiologist Physical Status I–II. Patients were randomly assigned to VCV group (n = 30), where VCV mode was maintained through anaesthesia, or the PCV group (n = 30), where ventilation mode was changed to PCV after the establishment of 40° Trendelenburg position and pneumoperitoneum. Respiratory (peak and mean airway pressure [APpeak, APmean], dynamic lung compliance [Cdyn] and arterial blood gas analysis) and haemodynamics variables (heart rate, mean blood pressure [MBP] central venous pressure) were measured at baseline (T1), post-Trendelenburg position at 60 min (T2), 120 min (T3) and after resuming supine position (T4). Results: Demographic profile, haemodynamic variables, oxygen saturation and minute ventilation (MV) were comparable between two groups. Despite similar values of APmean, APpeak was significantly higher in VCV group at T2 and T3 as compared to PCV group (P < 0.001). Cdyn and PaCO2 were also better in PCV group than in VCV group (P < 0.001 and 0.045, respectively). Conclusion: PCV should be preferred in robotic pelvic surgeries as it offers lower airway pressures, greater Cdyn and a better-preserved ventilation-perfusion matching for the same levels of MV. PMID:28216699

  4. Effect of Switching between Pressure-controlled and Volume-controlled Ventilation on Respiratory Mechanics and Hemodynamics in Obese Patients during Abdominoplasty

    PubMed Central

    Messeha, Medhat Mikhail

    2017-01-01

    Background: The ideal intraoperative ventilation strategy in obese patients remains obscure. This prospective, randomized study was designed to evaluate the effect of pressure-controlled ventilation (PCV) before or after volume-controlled ventilation (VCV) on lung mechanics and hemodynamics variables in obese patients subjected to abdominoplasty operation. Patients and Methods: The study included forty patients with body mass index 30–45 kg/m2 subjected to abdominoplasty. All patients were randomly allocated in two groups after the induction of general anesthesia (twenty patients each), according to intraoperative ventilatory strategy. Group I (P-V): started with PCV until the plication of rectus muscle changes into VCV till the end of surgery. Group II (V-P): started with VCV until the plication of rectus muscle changes into PCV till the end of surgery. Lung mechanics, hemodynamics variables (heart rate and mean blood pressure), and arterial blood gases (ABGs) were recorded. Results: No significant difference in the hemodynamics and ABGs were recorded between the studied groups. The use of PCV after VCV induced the improvement of lung mechanics. Conclusion: Switching from VCV to PCV is preferred to improve intraoperative oxygenation and lung compliance without adverse hemodynamic effects in obese patients. PMID:28298763

  5. Effects of pressure-controlled and volume-controlled ventilation on respiratory mechanics and systemic stress response during laparoscopic cholecystectomy.

    PubMed

    Sen, Oznur; Umutoglu, Tarik; Aydın, Nurdan; Toptas, Mehmet; Tutuncu, Ayse Cigdem; Bakan, Mefkur

    2016-01-01

    Pressure-controlled ventilation (PCV) is less frequently employed in general anesthesia. With its high and decelerating inspiratory flow, PCV has faster tidal volume delivery and different gas distribution. The same tidal volume setting, delivered by PCV versus volume-controlled ventilation (VCV), will result in a lower peak airway pressure and reduced risk of barotrauma. We hypothesized that PCV instead of VCV during laparoscopic surgery could achieve lower airway pressures and reduce the systemic stress response. Forty ASA I-II patients were randomly selected to receive either the PCV (Group PC, n = 20) or VCV (Group VC, n = 20) during laparoscopic cholecystectomy. Blood sampling was made for baseline arterial blood gases (ABG), cortisol, insulin, and glucose levels. General anesthesia with sevoflurane and fentanyl was employed to all patients. After anesthesia induction and endotracheal intubation, patients in Group PC were given pressure support to form 8 mL/kg tidal volume and patients in Group VC was maintained at 8 mL/kg tidal volume calculated using predicted body weight. All patients were maintained with 5 cmH2O positive-end expiratory pressure (PEEP). Respiratory parameters were recorded before and 30 min after pneumoperitonium. Assessment of ABG and sampling for cortisol, insulin and glucose levels were repeated 30 min after pneumoperitonium and 60 min after extubation. The P-peak levels observed before (18.9 ± 3.8 versus 15 ± 2.2 cmH2O) and during (23.3 ± 3.8 versus 20.1 ± 2.9 cmH2O) pneumoperitoneum in Group VC were significantly higher. Postoperative partial arterial oxygen pressure (PaO2) values are higher (98 ± 12 versus 86 ± 11 mmHg) in Group PC. Arterial carbon dioxide pressure (PaCO2) values (41.8 ± 5.4 versus 36.7 ± 3.5 mmHg) during pneumoperitonium and post-operative mean cortisol and insulin levels were higher in Group VC. When compared to VCV mode, PCV mode may improve compliance during pneumoperitoneum

  6. Are tidal volume measurements in neonatal pressure-controlled ventilation accurate?

    PubMed

    Chow, Lily C; Vanderhal, Andre; Raber, Jorge; Sola, Augusto

    2002-09-01

    Bedside pulmonary mechanics monitors (PMM) have become useful in ventilatory management in neonates. These monitors are used more frequently due to recent improvements in data-processing capabilities. PMM devices are often part of the ventilator or are separate units. The accuracy and reliability of these systems have not been carefully evaluated. We compared a single ventilatory parameter, tidal volume (V(t)), as measured by several systems. We looked at two freestanding PMMs: the Ventrak Respiratory Monitoring System (Novametrix, Wallingford, CT) and the Bicore CP-100 Neonatal Pulmonary Monitor (Allied Health Care Products, Riverside, CA), and three ventilators with built-in PMM: the VIP Bird Ventilator (Bird Products Corp., Palm Springs, CA), Siemens Servo 300A (Siemens-Elema AB, Solna, Sweden), and Drager Babylog 8000 (Drager, Inc., Chantilly, VA). A calibrated syringe (Hans Rudolph, Inc., Kansas City, MO) was used to deliver tidal volumes of 4, 10, and 20 mL to each ventilator system coupled with a freestanding PMM. After achieving steady state, six consecutive V(t) readings were taken simultaneously from the freestanding PMM and each ventilator. In a second portion of the bench study, we used pressure-control ventilation and measured exhaled tidal volume (V(te)) while ventilating a Bear Test Lung with the same three ventilators. We adjusted peak inspiratory pressure (PIP) under controlled conditions to achieve the three different targeted tidal volumes on the paired freestanding PMM. Again, six V(te) measurements were recorded for each tidal volume. Means and standard deviations were calculated.The percentage difference in measurement of V(t) delivered by calibrated syringe varied greatly, with the greatest discrepancy seen in the smallest tidal volumes, by up to 28%. In pressure control mode, V(te) as measured by the Siemens was significantly overestimated by 20-95%, with the biggest discrepancy at the smallest V(te), particularly when paired with the Bicore

  7. The Effect of Pressure-Controlled Ventilation and Volume-Controlled Ventilation in Prone Position on Pulmonary Mechanics and Inflammatory Markers.

    PubMed

    Şenay, Hasan; Sıvacı, Remziye; Kokulu, Serdar; Koca, Buğra; Bakı, Elif Doğan; Ela, Yüksel

    2016-08-01

    The aim of this present study is to compare the effect of pressure-controlled ventilation and volume-controlled ventilation on pulmonary mechanics and inflammatory markers in prone position. The study included 41 patients undergoing to vertebrae surgery. The patients were randomized into two groups: Group 1 received volume-controlled ventilation, while group 2 received pressure-controlled ventilation. The demographic data, pulmonary mechanics, the inflammatory marker levels just after the induction of anesthetics, at the 6th and 12th hours, and gas analysis from arterial blood samples taken at the beginning and the 30th minute were recorded. The inflammatory marker levels increased in both groups, without any significant difference among groups. Peak inspiratory pressure level was higher in the volume-controlled ventilation group. This study revealed that there is no difference regarding inflammatory marker levels between volume- and pressure-controlled ventilation.

  8. Effects of assisted ventilation on the work of breathing: volume-controlled versus pressure-controlled ventilation.

    PubMed

    Cinnella, G; Conti, G; Lofaso, F; Lorino, H; Harf, A; Lemaire, F; Brochard, L

    1996-03-01

    During assisted ventilation, the same tidal volume can be delivered in different ways, with the possibility for the physician to vary the ventilatory target (pressure or volume) and the peak flow setting. We compared the effects on the respiratory work rate of assisted ventilation, delivered either with a square wave flow pattern (assist control ventilation [ACV]) or with a decelerating flow pattern and a constant pressure (assisted pressure-control ventilation [APCV]). In the first part of the study where seven patients were studied, inspiratory time and tidal volume were similar in the two modes of ventilation. High and moderate levels of tidal volume (VT) were studied (12 ml/kg and 8 ml/kg, respectively). To obtain moderate VT, inspiratory time was kept constant and, therefore, mean inspiratory flow was reduced. At high VT, no difference between ACV and APCV was noted for breathing pattern, respiratory drive indexes, respiratory muscle work, or arterial blood gases. All patients exhibited respiratory alkalosis. At moderate VT, normal pH was achieved. In this situation significantly lower levels were observed during APCV than during ACV for the power of breathing (10 +/- 2 versus 19 +/- 5 J/min, p<0.05), transdiaphragmatic pressure swing (7 +/- 1 versus 11 +/- 2 cm H2O, p<0.05), and pressure-time index (252 +/- 43 versus 484 +/- 114 cm H2O.s, p<0.05), even though breathing pattern and gas exchange were similar. In the second part of the study where six additional patients were studied, tidal volume was kept constant at a moderate level (8 ml/kg), and we studied the effect of shortening inspiratory time and increasing mean inspiratory flow. At moderate VT and high inspiratory flow, no significant differences could be found between ACV and APCV, and although pressure-time index tended to be lower during APCV, absolute levels of effort were of small magnitude (56 +/- 55 versus 76 +/- 55 cm H2O.s). We conclude that at moderate VT and low flow rates only, inspiratory

  9. Pressure dynamic characteristics of pressure controlled ventilation system of a lung simulator.

    PubMed

    Shi, Yan; Ren, Shuai; Cai, Maolin; Xu, Weiqing; Deng, Qiyou

    2014-01-01

    Mechanical ventilation is an important life support treatment of critically ill patients, and air pressure dynamics of human lung affect ventilation treatment effects. In this paper, in order to obtain the influences of seven key parameters of mechanical ventilation system on the pressure dynamics of human lung, firstly, mechanical ventilation system was considered as a pure pneumatic system, and then its mathematical model was set up. Furthermore, to verify the mathematical model, a prototype mechanical ventilation system of a lung simulator was proposed for experimental study. Last, simulation and experimental studies on the air flow dynamic of the mechanical ventilation system were done, and then the pressure dynamic characteristics of the mechanical system were obtained. The study can be referred to in the pulmonary diagnostics, treatment, and design of various medical devices or diagnostic systems.

  10. Non-invasive ventilation with intelligent volume-assured pressure support versus pressure-controlled ventilation: effects on the respiratory event rate and sleep quality in COPD with chronic hypercapnia

    PubMed Central

    Nilius, Georg; Katamadze, Nato; Domanski, Ulrike; Schroeder, Maik; Franke, Karl-Josef

    2017-01-01

    Background COPD patients who develop chronic hypercapnic respiratory failure have a poor prognosis. Treatment of choice, especially the best form of ventilation, is not well known. Objectives This study compared the effects of pressure-controlled (spontaneous timed [ST]) non-invasive ventilation (NIV) and NIV with intelligent volume-assured pressure support (IVAPS) in chronic hypercapnic COPD patients regarding the effects on alveolar ventilation, adverse patient/ventilator interactions and sleep quality. Methods This prospective, single-center, crossover study randomized patients to one night of NIV using ST then one night with the IVAPS function activated, or vice versa. Patients were monitored using polysomnography (PSG) and transcutaneous carbon dioxide pressure (PtcCO2) measurement. Patients rated their subjective experience (total score, 0–45; lower scores indicate better acceptability). Results Fourteen patients were included (4 females, age 59.4±8.9 years). The total number of respiratory events was low, and similar under pressure-controlled (5.4±6.7) and IVAPS (8.3±10.2) conditions (P=0.064). There were also no clinically relevant differences in PtcCO2 between pressure-controlled and IVAPS NIV (52.9±6.2 versus 49.1±6.4 mmHg). Respiratory rate was lower under IVAPS overall; between-group differences reached statistical significance during wakefulness and non-rapid eye movement sleep. Ventilation pressures were 2.6 cmH2O higher under IVAPS versus pressure-controlled ventilation, resulting in a 20.1 mL increase in breathing volume. Sleep efficiency was slightly higher under pressure-controlled ventilation versus IVAPS. Respiratory arousals were uncommon (24.4/h [pressure-controlled] versus 25.4/h [IVAPS]). Overall patient assessment scores were similar, although there was a trend toward less discomfort during IVAPS. Conclusion Our results show that IVAPS NIV allows application of higher nocturnal ventilation pressures versus ST without affecting sleep

  11. Pneumococcal Vaccines (PCV, PPSV)

    MedlinePlus

    ... Your 1- to 2-Year-Old Your Child's Immunizations: Pneumococcal Vaccines (PCV, PPSV) KidsHealth > For Parents > Your ... but also help stop the infections from spreading. Immunization Schedule PCV13 immunizations are given to all infants ...

  12. Effect of Pressure Controlled Waveforms on Flow Transport and Gas mixing in a Patient Specific Lung Model during Invasive High Frequency Oscillatory Ventilation

    NASA Astrophysics Data System (ADS)

    Alzahrany, Mohammed; Banerjee, Arindam

    2012-11-01

    A computational fluid dynamic study is carried out to investigate gas transport in patient specific human lung models (based on CT scans) during high frequency oscillatory ventilation (HFOV). Different pressure-controlled waveforms and various ventilator frequencies are studied to understand the effect of flow transport and gas mixing during these processes. Three different pressure waveforms are created by solving the equation of motion subjected to constant lung wall compliance and flow resistance. Sinusoidal, exponential and constant waveforms shapes are considered with three different frequencies 6, 10 and 15 Hz and constant tidal volume 50 ml. The velocities are calculated from the obtained flow rate and imposed as inlet flow conditions to represent the mechanical ventilation waveforms. An endotracheal tube ETT is joined to the model to account for the effect of the invasive management device with the peak Reynolds number (Re) for all the cases ranging from 6960 to 24694. All simulations are performed using high order LES turbulent model. The gas transport near the flow reversal will be discussed at different cycle phases for all the cases and a comparison of the secondary flow structures between different cases will be presented.

  13. Validation of indirect calorimetry for measurement of energy expenditure in healthy volunteers undergoing pressure controlled non-invasive ventilation support.

    PubMed

    Siirala, Waltteri; Noponen, Tommi; Olkkola, Klaus T; Vuori, Arno; Koivisto, Mari; Hurme, Saija; Aantaa, Riku

    2012-02-01

    The aim of this validation study was to assess the reliability of gas exchange measurement with indirect calorimetry among subjects who undergo non-invasive ventilation (NIV). Oxygen consumption (VO2) and carbon dioxide production (VCO2) were measured in twelve healthy volunteers. Respiratory quotient (RQ) and resting energy expenditure (REE) were then calculated from the measured VO2 and VCO2 values. During the measurement period the subjects were breathing spontaneously and ventilated using NIV. Two different sampling air flow values 40 and 80 l/min were used. The gas leakage from the measurement setup was assessed with a separate capnograph. The mean weight of the subjects was 93 kg. Their mean body mass index was 29 (range 22-40) kg/m2. There was no statistically significant difference in the measured values for VO2, VCO2, RQ and REE during NIV-supported breathing and spontaneous breathing. The change of sampling air flow had no statistically significant effect on any of the above parameters. We found that REE can be accurately measured with an indirect calorimeter also during NIV-supported breathing and the change of sampling air flow does not distort the gas exchange measurement. A higher sampling air flow in indirect calorimetry decreases the possibility for air leakages in the measurement system and increases the reliability of REE measurement.

  14. The role of ventilation mode using a laryngeal mask airway during gynecological laparoscopy on lung mechanics, hemodynamic response and blood gas analysis

    PubMed Central

    Jarahzadeh, Mohammad Hossein; Halvaei, Iman; Rahimi-Bashar, Farshid; Behdad, Shekoufeh; Abbasizadeh Nasrabady, Rouhollah; Yasaei, Elahe

    2016-01-01

    Background: There are two methods for ventilation in gynecological laparoscopy: volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV). Objective: To compare the lung mechanics, hemodynamic response and arterial blood gas analysis and gas exchange of two modes of VCV and PCV using laryngeal mask airway (LMA) at different time intervals. Materials and Methods: Sixty infertile women referred for diagnostic laparoscopy, based on ventilation mode, were randomly divided into two groups of VCV (tidal volume: 10 ml/kg) and PCV. In the PCV group, ventilation was initiated with a peak airway pressure (tidal volume: 10 ml/kg, upper limit: 35 cm H2O). In both groups, the arterial blood samples were taken in several time intervals (5, 10 and 15 min after LMA insertion) for blood gas evaluation. Also the lung mechanics parameters were continuously monitored and were recorded at different time intervals. Results: There were no significant differences for patient’s age, weight, height and BMI in two groups. The peak and plateau airway pressure were significantly higher in VCV group compared to PCV group 5 and 10 min after insertion of LMA. PaO2 was significantly higher after 10 and 15 min in VCV group compared to PCV group (p=0.005 and p=0.03, respectively). PaCO2 showed significant increase after 5 min in PCV group, but the differences were not significant after 10 and 15 min in two groups. The end tidal CO2 showed significant increase after 10 and 15 min in VCV compared to PCV group. Conclusion: Both VCV and PCV seem to be suitable for gynecological laparoscopy. However, airway pressures are significantly lower in PCV compared to VCV. PMID:28066834

  15. Pneumococcal Vaccines (PCV, PPSV)

    MedlinePlus

    ... to 2-Year-Old Your Child's Immunizations: Pneumococcal Vaccines (PCV, PPSV) KidsHealth > For Parents > Your Child's Immunizations: ... or HIV infection); or cochlear implants. Why the Vaccines Are Recommended Children younger than 2 years old, ...

  16. Pneumococcal Conjugate Vaccine (PCV13)

    MedlinePlus

    ... the United States.Treatment of pneumococcal infections with penicillin and other drugs is not as effective as ... should not get PCV13.Anyone with a severe allergy to any component of PCV13 should not get ...

  17. FISH in polycythemia vera (PCV)

    SciTech Connect

    Amiel, A.; Gaber, E.; Manor, Y.

    1994-09-01

    Trisomies 8 and 9 are the most common numerical abnormalities in polycythemia vera (PCV). However, their role in the pathogenesis of the disease is unclear as is their diagnostic or prognostic value. We evaluated the role of fluorescent in-situ hybridization (FISH) as compared to chromosome analysis in the detection of trisomies 8 or 9 in peripheral blood cells of 14 PCV and 5 secondary PCV patients. Using FISH, we found trisomies 8 and 9 in 10 PCV patients above the cutoff levels of 5%. However, no patient with the secondary PCV reached the cutoff level. Out of 10 PCV patients in whom the trisomy was detected by FISH, only in 3 was this trisomy also detected by routine cytogenetics. The incidence of the finding of trisomy 9 correlates with the duration of the disease, suggesting that this is not the primary event in PCV. FISH is a sensitive, convenient and rapid method for diagnosis and follow-up of chromosome aberrations in PCV patients. Application of FISH to larger cohort of patients may provide valuable information regarding their role in initiation and progession of the disease.

  18. Anaesthesia ventilators

    PubMed Central

    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

  19. Ventilation.

    PubMed

    Turner, W A; Bearg, D W; Brennan, T

    1995-01-01

    This chapter begins with an overview of the history of ventilation guidelines, which has led to the guidelines that are in effect today. Of particular interest is the most recent return in the past 5 years to ventilation rates that more closely reflect a mean or average of the range of guidelines that have existed over the past century. OSHA's and the EPA's recognition of the need to operate ventilation systems in buildings in an accountable manner is also of note. Of even more interest is the resurgence of the concept of minimum mixing and once-through ventilation air that has been pursued in parts of Northern Europe for the past 10 years, and in a school that is being designed with this concept in New Hampshire. In addition, the design concept of equipping office buildings with low pressure drop high efficiency particle filtration to remove fine particles from all of the air that is supplied to the occupants is being used increasingly in the U.S. This chapter also presents an overview of the various types of ventilation systems found in homes and commercial office buildings and the common indoor air quality problems that may be associated with them. It also offers an overview of common HVAC evaluation techniques that can be used to determine if a ventilation system is performing in a manner that makes sense for the use of the space and the needs of the occupants. Are the occupants receiving a reasonable supply of outdoor air? Is the air that they receive of reasonable quality? Are obvious pollutants being exhausted? Ventilation systems have become extremely complex and more difficult to run and maintain over the past 40 years. This trend will continue to drive the need for professionally maintained HVAC equipment that is serviced and run by individuals who are accountable for the quality of the air that the system delivers.

  20. Tracheostomy and mechanical ventilation weaning in children affected by respiratory virus according to a weaning protocol in a pediatric intensive care unit in Argentina: an observational restrospective trial

    PubMed Central

    2011-01-01

    We describe difficult weaning after prolonged mechanical ventilation in three tracheostomized children affected by respiratory virus infection. Although the spontaneous breathing trials were successful, the patients failed all extubations. Therefore a tracheostomy was performed and the weaning plan was begun. The strategy for weaning was the decrease of ventilation support combining pressure control ventilation (PCV) with increasing periods of continuous positive airway pressure + pressure support ventilation (CPAP + PSV) and then CPAP + PSV with increasing intervals of T-piece. They presented acute respiratory distress syndrome on admission with high requirements of mechanical ventilation (MV). Intervening factors in the capabilities and loads of the respiratory system were considered and optimized. The average MV time was 69 days and weaning time 31 days. We report satisfactory results within the context of a directed weaning protocol. PMID:21244710

  1. Porcine circovirus type 2 (PCV2) vaccination is effective in reducing disease and PCV2 shedding in semen of boars concurrently infected with PCV2 and Mycoplasma hyopneumoniae.

    PubMed

    Opriessnig, T; Madson, D M; Schalk, S; Brockmeier, S; Shen, H G; Beach, N M; Meng, X J; Baker, R B; Zanella, E L; Halbur, P G

    2011-07-15

    The objectives were to determine whether the amount of porcine circovirus type 2 (PCV2) shed in semen increased in boars experimentally coinfected with Mycoplasma hyopneumoniae (MHYO), and whether PCV2 vaccination of boars prior to PCV2 exposure reduced PCV2 viremia and virus shedding in semen. Twelve specific-pathogen-free PCV2- and MHYO-naïve boars were randomly and equally assigned to one of four groups. Six boars were vaccinated against PCV2 (VAC) on Day 0; three PCV2 vaccinated and three non-vaccinated boars were inoculated with MHYO on Day 21, and all boars were challenged with PCV2 on Day 35. The four treatment groups included PCV2-Infected (I), VAC-PCV2-I, MHYO-PCV2-Coinfected (CoI), and VAC-MHYO-PCV2-CoI. Semen, blood swabs, feces, and serum samples were collected weekly until Day 70. All vaccinated boars had seroconverted to PCV2 by Day 35. Between Days 28 and 35, MHYO boars developed moderate respiratory disease, characterized by coughing, respiratory distress, mucopurulent nasal discharge and loss of body condition. One MHYO-PCV2-CoI boar died on Day 50. Boars in the PCV2-I and MHYO-PCV2-CoI groups had significantly higher PCV2 DNA loads in blood swabs than the remaining boars. Moreover, PCV2 vaccination significantly reduced the incidence and amount of PCV2 shedding in semen and feces. In summary, although concurrent MHYO infection did not influence PCV2 shedding patterns, coinfection of boars with PCV2 and MHYO resulted in severe clinical disease and viral shedding was significantly decreased by PCV2 vaccination.

  2. Commercial PCV2a-based vaccines are effective in protecting naturally PCV2b-infected finisher pigs against experimental challenge with a 2012 mutant PCV2.

    PubMed

    Opriessnig, Tanja; Gerber, Priscilla F; Xiao, Chao-Ting; Halbur, Patrick G; Matzinger, Shannon R; Meng, Xiang-Jin

    2014-07-23

    Current commercial PCV2 vaccines are all based on PCV2a and have been shown to be effective in reducing PCV2a and PCV2b viremia and PCV2-associated lesions and disease. The recent emergence of novel mutant PCV2 (mPCV2) strains and linkage of mPCV2 with cases of porcine circovirus associated disease (PCVAD) in vaccinated herds have raised concerns over emergence of vaccine-escape mutants and reduced efficacy of PCV2a-based vaccines. The aim of this study was to determine the ability of three commercial PCV2a-based vaccines administered in the presence of an ongoing PCV2b infection and passively-acquired anti-PCV2 antibodies to protect conventional pigs against experimental challenge with mPCV2 at 11 weeks of age. Fifty naturally PCV2b-infected 2-week-old pigs were divided into five treatment groups with 10 pigs each. Pigs were unvaccinated (positive and negative controls) or vaccinated at 3 (VAC-A, VAC-B, VAC-C) and at 5 weeks of age (VAC-C). At 11 weeks of age, all pigs except the negative controls were challenged with a 2012 U.S. strain of mPCV2. The experiment was terminated 21 days after challenge. Under the conditions of this study, vaccinated pigs were protected against PCV2 viremia and lesions whereas non-vaccinated pigs were not. Moreover, concurrent PCV2b and mPCV2 infection was demonstrated in all positive controls and 3/10 had microscopic lesions consistent with PCVAD while negative controls infected with PCV2b alone did not develop PCVAD. The results indicate that concurrent PCV2b/mPCV2 infection can trigger PCVAD development and that commercial vaccines are effective in protecting conventional pigs against emerging mPCV2 strains.

  3. Porcine circovirus type 2 (PCV2) vaccination is effective in reducing disease and PCV2 shedding in semen of boars concurrently infected with PCV2 and Mycoplasma hyopneumoniae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to determine if the amount of porcine circovirus type 2 (PCV2) shed in semen will be increased in boars experimentally coinfected with Mycoplasma hyopneumoniae (MHYO) and if PCV2 vaccination of the boars prior to PCV2 exposure will result in reduced PCV2 viremia and...

  4. A chimeric porcine circovirus (PCV) with the immunogenic capsid gene of the pathogenic PCV type 2 (PCV2) cloned into the genomic backbone of the nonpathogenic PCV1 induces protective immunity against PCV2 infection in pigs.

    PubMed

    Fenaux, M; Opriessnig, T; Halbur, P G; Elvinger, F; Meng, X J

    2004-06-01

    Porcine circovirus type 2 (PCV2) is associated with postweaning multisystemic wasting syndrome in pigs, whereas PCV1 is nonpathogenic. We previously demonstrated that a chimeric PCV1-2 virus (with the immunogenic capsid gene of PCV2 cloned into the backbone of PCV1) induces an antibody response to the PCV2 capsid protein and is attenuated in pigs. Here, we report that the attenuated chimeric PCV1-2 induces protective immunity to wild-type PCV2 challenge in pigs. A total of 48 specific-pathogen-free piglets were randomly and equally assigned to four groups of 12 pigs each. Pigs in group 1 were vaccinated by intramuscular injection with 200 microg of the chimeric PCV1-2 infectious DNA clone. Pigs in group 2 were vaccinated by intralymphoid injection with 200 microg of a chimeric PCV1-2 infectious DNA clone. Pigs in group 3 were vaccinated by intramuscular injection with 10(3.5) 50% tissue culture infective doses (TCID(50)) of the chimeric PCV1-2 live virus. Pigs in group 4 were not vaccinated and served as controls. By 42 days postvaccination (DPV), the majority of pigs had seroconverted to PCV2 capsid antibody. At 42 DPV, all pigs were challenged intranasally and intramuscularly with 2 x 10(4.5) TCID(50) of a wild-type pathogenic PCV2 virus. By 21 days postchallenge (DPC), 9 out of the 12 group 4 pigs were viremic for PCV2. Vaccinated animals in groups 1 to 3 had no detectable PCV2 viremia after challenge. At 21 DPC the lymph nodes in the nonvaccinated pigs were larger (P < 0.05) than those of vaccinated pigs. The PCV2 genomic copy loads in lymph nodes were reduced (P < 0.0001) in vaccinated pigs. Moderate amounts of PCV2 antigen were detected in most lymphoid tissues of nonvaccinated pigs but in only 1 of 36 vaccinated pigs. Mild-to-severe lymphoid depletion and histiocytic replacement were detected in lymphoid tissues in the majority of nonvaccinated group 4 pigs but in only a few vaccinated group 1 to 3 pigs. The data from this study indicated that when given

  5. Singular PCV2a or PCV2b infection results in apoptosis of hepatocytes in clinically affected gnotobiotic pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Porcine circovirus type 2 (PCV2) which can be further subdivide into two main genotypes, PCV2a and PCV2b, is often clinically associated with respiratory signs, failure-to-thrive, and diarrhea. The precise pathogenesis of PCV2, and in particular its involvement in apoptosis, is controversial. The ob...

  6. Blood Pressure Control

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Engineering Development Laboratory developed a system for the cardiovascular study of weightless astronauts. This was designed to aid people with congestive heart failure and diabetes. While in space, astronauts' blood pressure rises, heart rate becomes unstable, and there are sometimes postflight lightheadedness or blackouts. The Baro-Cuff studies the resetting of blood pressure. When a silicone rubber chamber is strapped to the neck, the Baro-Cuff stimulates the carotid arteries by electronically controlled pressure application. Blood pressure controls in patients may be studied.

  7. Pneumococcal Conjugate Vaccine (PCV13): What You Need to Know

    MedlinePlus

    ... the United States. Treatment of pneumococcal infections with penicillin and other drugs is not as effective as ... should not get PCV13. Anyone with a severe allergy to any component of PCV13 should not get ...

  8. Association of concurrent porcine circovirus (PCV) 2a and 2b infection with PCV associated disease in vaccinated pigs.

    PubMed

    Gerber, Priscilla F; Johnson, John; Shen, Huigang; Striegel, Dave; Xiao, Chao-Ting; Halbur, Patrick G; Opriessnig, Tanja

    2013-10-01

    Investigations were performed to characterize porcine circovirus (PCV) 2 infection in 10 week old pigs from a case of apparent vaccine failure. Thirty serum samples were collected from affected or non-affected pigs and tested for anti-PCV2 antibodies and PCV2 DNA. To address potential PCV2 vaccine compliance issues, samples were tested for antibodies against baculovirus and Mycoplasma hyopneumoniae antigens present in the PCV2 vaccine utilized in this herd. Both PCV2a and PCV2b DNA were detected in 76.6% (90% positive for PCV2a, 86.6% positive for PCV2b), anti-PCV2 IgG in 90%, anti-baculovirus IgG in 50%, and anti-M. hyopneumoniae IgG in 43.3% of the samples. Frequency of baculovirus and M. hyopneumoniae seropositive pigs was significantly lower in affected pigs. The finding that only 50% of the pigs developed a detectable immune response to vaccination suggests poor vaccine compliance or efficacy. Concurrent PCV2a and PCV2b infection was common and may have resulted in enhanced PCV2 replication.

  9. PCV2 Vaccination Prevented Clinical PCVAD and Reduced PCV2 Viremia and Semen Shedding in Boars Concurrently Infected with PCV2b and Mycoplasma hyopneumoiae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction. It has been determined that porcine circovirus type 2 (PCV2) DNA is shed in semen of naturally and experimentally infected boars (1). Recently, it also has been shown that PCV2 DNA present in semen is infectious in a swine bioassay model (2). However, under experimental conditions the ...

  10. A chimeric virus created by DNA shuffling of the capsid genes of different subtypes of porcine circovirus type 2 (PCV2) in the backbone of the non-pathogenic PCV1 induces protective immunity against the predominant PCV2b and the emerging PCV2d in pigs.

    PubMed

    Matzinger, Shannon R; Opriessnig, Tanja; Xiao, Chao-Ting; Catanzaro, Nicholas; Beach, Nathan M; Slade, David E; Nitzel, Gregory P; Meng, Xiang-Jin

    2016-11-01

    Porcine circovirus type 2 (PCV2) is the primary causative agent of porcine circovirus-associated disease (PCVAD). Available commercial vaccines all target PCV2a subtype, although the circulating predominant subtype worldwide is PCV2b, and the emerging PCV2d subtype is also increasingly associated with PCVAD. Here we molecularly bred genetically-divergent strains representing PCV2a, PCV2b, PCV2c, PCV2d, and "divergent PCV2a" subtypes by DNA-shuffling of the capsid genes to produce a chimeric virus representing PCV2 global genetic diversity. When placed in the PCV2a backbone, one chimeric virus (PCV2-3cl14) induced higher neutralizing antibody titers against different PCV2 subtypes. Subsequently, a candidate vaccine (PCV1-3cl14) was produced by cloning the shuffled 3cl14 capsid into the backbone of the non-pathogenic PCV1. A vaccine efficacy study revealed that chimeric virus PCV1-3cl14 induces protective immunity against challenge with PCV2b or PCV2d in pigs. The chimeric PCV1-3cl14 virus is a strong candidate for a novel vaccine in pigs infected with variable PCV2 strains.

  11. Porcine circovirus (PCV) removal by Q sepharose fast flow chromatography.

    PubMed

    Yang, Bin; Wang, Hua; Ho, Cintia; Lester, Philip; Chen, Qi; Neske, Florian; Baylis, Sally A; Blümel, Johannes

    2013-01-01

    The recently discovered contamination of oral rotavirus vaccines led to exposure of millions of infants to porcine circovirus (PCV). PCV was not detected by conventional virus screening tests. Regulatory agencies expect exclusion of adventitious viruses from biological products. Therefore, methods for inactivation/removal of viruses have to be implemented as an additional safety barrier whenever feasible. However, inactivation or removal of PCV is difficult. PCV is highly resistant to widely used physicochemical inactivation procedures. Circoviruses such as PCV are the smallest viruses known and are not expected to be effectively removed by currently-used virus filters due to the small size of the circovirus particles. Anion exchange chromatography such as Q Sepharose(®) Fast Flow (QSFF) has been shown to effectively remove a range of viruses including parvoviruses. In this study, we investigated PCV1 removal by virus filtration and by QSFF chromatography. As expected, PCV1 could not be effectively removed by virus filtration. However, PCV1 could be effectively removed by QSFF as used during the purification of monoclonal antibodies (mAbs) and a log10 reduction value (LRV) of 4.12 was obtained.

  12. PCV2d-2 is the predominant type of PCV2 DNA in pig samples collected in the U.S. during 2014-2016.

    PubMed

    Xiao, Chao-Ting; Harmon, Karen M; Halbur, Patrick G; Opriessnig, Tanja

    2016-12-25

    Porcine circovirus type 2 (PCV2) vaccination was introduced in the US in 2006 and since has been adopted by most pig producers. While porcine circovirus associated disease (PCVAD) outbreaks are now relatively uncommon in the US, PCV2 remains a concern which is emphasized by increasing numbers of PCR and sequencing requests for PCV2. In the present study, randomly selected lung tissues from 586 pigs submitted in 2015 were tested for presence of PCV2 DNA. Positive samples were further characterized by sequencing and combined with available PCV2 open-reading-frame (ORF) 2 sequences from the client data base of the Iowa State University Veterinary Diagnostic Laboratory. The prevalence of PCV2 in the randomly selected lung tissues was 23% (135/586) with 11.3% PCV2a, 29% PCV2b and 71.8% for PCV2d subgroup PCV2d-2. A total of 455 ORF2 sequences obtained from 2014 through 2016 were analyzed and PCV2d accounted for 66.7% of the 2014 sequences, 71.8% of the 2015 sequences, and 72% of the 2016 sequences. Interestingly, only 1.9% (9/455) of the sequences belonged to the recently identified PCV2e genotype. The present data indicates that despite an almost 100% PCV2 vaccine coverage in the US, PCV2 DNA can still be detected in almost 1 of 4 randomly selected pig tissues. PCV2d-2 is now the predominant genotype in the USA suggesting that PCV2d-2 may have some advantage over PCV2a and PCV2b in its ability to replicate in pigs under vaccination pressure.

  13. Nasopharyngeal Pneumococcal Carriage among Healthy Children in Cyprus Post Widespread Simultaneous Implementation of PCV10 and PCV13 Vaccines

    PubMed Central

    Hadjipanayis, Adamos; Efstathiou, Elisavet; Alexandrou, Maria; Panayiotou, Loukia; Zachariadou, Chrystalla; Petrou, Panayiotis; Papaevangelou, Vasiliki

    2016-01-01

    The objective of the study was to describe the incidence of pneumococcal nasopharyngeal carriage, serotype distribution and antibiotic resistance profile of pneumococcal nasopharyngeal isolates in healthy children aged 6 to 36 months following the implementation of conjugate vaccines. A nasopharyngeal swab was collected from 1105 healthy children following a stratified random sampling between September 2013 and April 2014. Demographics, vaccination status and data on possible risk factors were recorded. Isolates were serotyped and tested for antibiotic susceptibility. The nasopharyngeal carriage rate was 25.3%. Among 1105 children enrolled, 393 had received PCV13 and 685 PCV10. The prevailing isolated serotypes were: 23A (14.3%), 15A (8.9%), 6C (8.6%), 23B (7.5%), 19A (5.4%) and 15B (5%). The proportion of non-vaccine serotypes, PCV10 serotypes, PCV13 additional serotypes (3, 6A, 19A) was 76.8%, 2.1% and 10.4% respectively. Although children, who were fully or partially vaccinated with PCV13, were 63% less likely to be colonized with additional PCV13 serotypes compared to those vaccinated with PCV10, the difference is not significant (95%Cl = 0.14–1.02, p = 0.053). The highest antibiotic non-susceptible rates were found for erythromycin (28.2%) and penicillin (27.9%). The overall multidrug resistance rate was 13.2%, with serotypes 24F (4/6), 15A (14/25) and 19A (6/15) being the main contributors. Carriage rate was similar between children vaccinated with PCV10 or PCV13. The high incidence of 15A serotype which is also multidrug resistant should be underlined. Ongoing surveillance is needed to monitor the dynamics on nasopharyngeal carriage. PMID:27706247

  14. Pneumococcal conjugate vaccine (PCV13) - What you need to know

    MedlinePlus

    ... the CDC Information Statement (VIS): www.cdc.gov/vaccines/hcp/vis/vis-statements/pcv13.html CDC review ... at the highest risk. Before there was a vaccine, the United States saw: more than 700 cases ...

  15. Controller modeling and evaluation for PCV electro-mechanical actuator

    NASA Technical Reports Server (NTRS)

    Parker, Joey K.

    1993-01-01

    Hydraulic actuators are currently used to operate the propellant control valves (PCV) for the space shuttle main engine (SSME) and other rocket engines. These actuators are characterized by large power to weight ratios, large force capabilities, and rapid accelerations, which favor their use in control valve applications. However, hydraulic systems are also characterized by susceptibility to contamination, which leads to frequent maintenance requirements. The Control Mechanisms Branch (EP34) of the Component Development Division of the Propulsion Laboratory at the Marshall Space Flight Center (MSFC) has been investigating the application of electromechanical actuators as replacements for the hydraulic units in PCV's over the last few years. This report deals with some testing and analysis of a PCV electromechanical actuator (EMA) designed and fabricated by HR Textron, Inc. This prototype actuator has undergone extensive testing by EP34 personnel since early 1993. At this time, the performance of the HR Textron PCV EMA does not meet requirements for position tracking.

  16. Ventilation and ventilators.

    PubMed

    Hayes, B

    1982-01-01

    The history of ventilation is reviewed briefly and recent developments in techniques of ventilation are discussed. Operating features of ventilators have changed in the past few years, partly as the result of clinical progress; yet, technology appears to have outstripped the clinician's ability to harness it most effectively. Clinical discipline and training of medical staff in the use of ventilators could be improved. The future is promising if clinician and designer can work together closely. Ergonomics of ventilators and their controls and the provision of alarms need special attention. Microprocessors are likely to feature prominently in the next generation of designs.

  17. Bench performance of ventilators during simulated paediatric ventilation.

    PubMed

    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.

  18. Chaos in blood pressure control.

    PubMed

    Wagner, C D; Nafz, B; Persson, P B

    1996-03-01

    characterising the stability and complexity of blood pressure control.

  19. Adaptive lung ventilation.

    PubMed

    Linton, D M

    2001-09-01

    Adaptive lung ventilation (ALV) is a method of closed-loop mechanical ventilation analogous to modern closed-loop technology in aviation such as the autopilot and automatic landing system. The algorithm of the controller of ALV is designed to automatically provide pressure-controlled synchronized intermittent mandatory ventilation (P-SIMV) and weaning as individually required in any clinical situation. The synchronized pressure limited breaths constantly adapt to the patient requirements to encourage optimal alveolar ventilation with minimal adverse physiological disturbance and timely weaning. The ease of application, efficiency, and safety of the first ALV controllers have been demonstrated in lung models, in patients with normal lungs undergoing general anesthesia, in patients requiring unusual positioning, in transition to and from one-lung anesthesia, and in long-term ventilation of patients with various lung pathologies and in weaning patients who have restrictive or obstructive pulmonary disease. Prospective comparative studies of ALV versus other currently used manually selected modes of mechanical ventilation, such as the one reported in this article, should confirm the safety and identify the benefits of this form of advanced closed-loop mechanical ventilation technology.

  20. Non-intrusive method of measuring PCV blowby constituents

    SciTech Connect

    Crane, M.E.; Ariga, S.; Boulard, R.; Lindamood, B.

    1994-10-01

    A technique is presented that has been successfully demonstrated to non-intrusively and quickly sample gases typically found in PCV systems. Color Detection Tubes (CDTs) were used with a simple sampling arrangement to monitor CO{sub 2}, NO{sub x}, O{sub 2}, and H{sub 2}O(g) at the closure line, crankcase, and PCV line. Measurements were accurate and could be made instantaneously. Short Path Thermal Desorbtion Tubes (SPTDTs) were used at the same engine locations for the characterization of fuel- and oil-derived hydrocarbon (HC) fractions and required only 50 cc samples. High engine loads caused pushover of blowby vapors as indicated by increased concentrations of CO{sub 2}, NO{sub x}, H{sub 2}O(g), and fuel HCs in the engines` fresh air inlets during WOT operation. Peak concentrations of blowby vapors were measured in the crankcase under no load and part throttle conditions. Oxygen concentrations always opposed the trends of CO{sub 2}, NO{sub x}, and H{sub 2}O(g). SPTDT data revealed that the PCV system consumes approximately 100-200 times more fuel vapors than oil vapors, on a mass basis; however, PCV-derived oil consumption represented almost 12 percent of total engine oil consumption under no load conditions. 8 refs., 17 figs.

  1. Porcine Circovirus type 2 (PCV2) causes apoptosis in experimentally inoculated BALB/c mice

    PubMed Central

    Kiupel, Matti; Stevenson, Gregory W; Galbreath, Elizabeth J; North, Adam; HogenEsch, Harm; Mittal, Suresh K

    2005-01-01

    Background We have previously described microscopic and electron microscopic alterations in lymphoid organs of PCV2 inoculated mice as apoptosis. In this study we wanted to investigate the molecular pathogenetic mechanism of PCV2-induced apoptosis. Eight-week old BALB/c mice were either sham inoculated (control mice) or inoculated intraperitoneally (ip) and intranasally (in) with a single (sPCV mice) or multiple (mPCV mice) doses of PCV2. Four control mice and 4 sPCV mice were sacrificed 7, 14, 28 and 42 days post inoculation (PI). All 4 mPCV mice were sacrificed 42 days PI. Following necropsy, immunohistochemistry for caspase 3 and in-situ TUNEL assay were performed on sections of spleen, lymph nodes, thymus and ileum from control, sPCV and mPCV mice. In addition, total RNA was extracted from spleens of control, sPCV and mPCV mice for simultaneous detection and semiquantitation of bcl-2 homologues and various caspase mRNAs using a multiprobe RNase protection assay system. Results PCV2 replicated and was associated with apoptosis in spleens, lymph nodes and Peyer's patches of infected BALB/c mice. Upregulation of caspase 1, 2, 3, 6, 7, 8, 11 and 12 and upregulation for the transcripts of apoptosis inhibitors bcl-2, bcl-w and bcl-X and apoptosis promoters' bax, bak and bad was detected in spleens of sPCV and mPCV mice, but not control mice. Apoptosis was further confirmed by light and electron microscopic morphology as well as by positive TUNEL assay and detection of activated caspase 3. PCV2 nucleic acid was detected by in-situ hybridization in the nuclei and cytoplasm of such apoptotic cells. Conclusion The data presented here support the hypothesis that PCV2 induces apoptosis mediated through the activation of caspases 8 and 3 in the spleens of infected mice. PMID:16259631

  2. Building pressurization control with rooftop air conditioners

    SciTech Connect

    Winter, S.

    1982-10-01

    The modulated exhaust fan appears to be the most cost effective positive means to maintain close building pressure control with rooftop air conditioning, but because building construction and applications vary, every building's pressure control needs must be analyzed. Requirements will vary from no relief to barometric dampers to return fans to modulated exhaust fans. As heating and cooling costs continue to rise and tighter building codes prevail, proper selection of building pressure control is one area that must be monitored more carefully by the HVAC system designer.

  3. Genetic Characterization of Type 2 Porcine Circovirus (PCV-2) from Pigs with Postweaning Multisystemic Wasting Syndrome in Different Geographic Regions of North America and Development of a Differential PCR-Restriction Fragment Length Polymorphism Assay To Detect and Differentiate between Infections with PCV-1 and PCV-2

    PubMed Central

    Fenaux, Martijn; Halbur, Patrick G.; Gill, Mike; Toth, Thomas E.; Meng, Xiang-Jin

    2000-01-01

    Postweaning multisystemic wasting syndrome (PMWS) is an emerging disease in swine. Increasing evidence indicates that a variant strain of porcine circovirus (PCV), designated type 2 PCV (PCV-2), is responsible for PMWS. To determine the extent of genetic heterogeneity of PCV-2 isolates, the complete genomes of six PCV-2 isolates from different regions of North America were amplified by PCR and sequenced. Sequence and phylogenetic analyses confirmed that two distinct genotypes of PCV exist: nonpathogenic genotype PCV-1 and PMWS-associated genotype PCV-2. However, within the PCV-2 genotype, several minor branches that have been identified appear to be associated with geographic origins. The genomic sequences of two French PCV-2 isolates diverge the most from those of other PCV-2 isolates and form a distinct branch. Other minor but distinguishable branches have also been identified for a Taiwan PCV-2 isolate and two of the Canadian PCV-2 isolates. All the U.S. PCV-2 isolates are closely related, but the Canadian isolates vary, to some extent, in their genomic sequences. The data from this study indicate that although the genome of PCV-2 is generally stable among different isolates, PCV-2 isolates from different geographic regions vary in their genomic sequences. This variation may have important implications for PCV-2 diagnosis and research. On the basis of genetic analyses of available PCV strains, a universal PCR-restriction fragment length polymorphism (PCR-RFLP) assay was developed to detect and differentiate between infections with PCV-1 and PCV-2. This PCR-RFLP assay should be useful for studying the pathogenesis of PCV-2, for detecting PCV-2 infection in pigs from different geographic regions, and for screening donor pigs for use in xenotransplantation. PMID:10878032

  4. PCV2 on the spot-A new method for the detection of single porcine circovirus type 2 secreting cells.

    PubMed

    Fossum, Caroline; Hjertner, Bernt; Lövgren, Tanja; Fuxler, Lisbeth; Charerntantanakul, Wasin; Wallgren, Per

    2014-02-01

    A porcine circovirus type 2 SPOT (PCV2-SPOT) assay was established to enumerate virus-secreting lymphocytes obtained from naturally infected pigs. The assay is based on the same principle as general ELISPOT assays but instead of detecting cytokine or immunoglobulin secretion, PCV2 particles are immobilized and detected as filter spots. The method was used to evaluate the influence of various cell activators on the PCV2 secretion in vitro and was also applied to study the PCV2 secretion by lymphocytes obtained from pigs in healthy herds and in a herd afflicted by postweaning multisystemic wasting disease (PMWS). Peripheral blood mononuclear cells (PBMCs) obtained from a pig with severe PMWS produced PCV2-SPOTs spontaneously whereas PBMCs obtained from pigs infected subclinically only generated PCV2-SPOTs upon in vitro stimulation. The PCV2 secretion potential was related to the PCV2 DNA content in the PBMCs as determined by two PCV2 real-time PCR assays, developed to differentiate between Swedish PCV2 genogroups 1 (PCV2a) and 3 (PCV2b). Besides the current application these qPCRs could simplify future epidemiological studies and allow genogroup detection/quantitation in dual infection experiments and similar studies. The developed PCV2-SPOT assay offers a semi-quantitative approach to evaluate the potential of PCV2-infected porcine cells to release PCV2 viral particles as well as a system to evaluate the ability of different cell types or compounds to affect PCV2 replication and secretion.

  5. Comparison of Porcine circovirus type 2 (PCV2) infection in light and heavy pigs of market age on farms with routine PCV2 vaccination.

    PubMed

    Lyoo, Kwang-Soo; Joo, Han Soo; Davies, Peter R; Han, Jeong Hee

    2012-07-01

    Commercial vaccines against Porcine circovirus type 2 (PCV2) are widely used on swine farms. Marked body weight variation at marketing age is a problem on conventional pig farms using all-in/all-out barn management. The aim of this study was to investigate whether PCV2 infection could be a factor influencing body weight variation. Seven conventional farms that routinely used PCV2 vaccination were selected, and 60 serum samples from light and heavy pigs at each site were tested for PCV2 antibody titers and viremia. At 3 farms the mean antibody titer, proportion of viremic pigs, and virus load differed significantly between the light and heavy groups. These preliminary results suggest that PCV2 infection may be a factor contributing to weight variation in vaccinated market-age hogs.

  6. Expression of PCV2 antigen in the ovarian tissues of gilts

    PubMed Central

    TUMMARUK, Padet; PEARODWONG, Pachara

    2015-01-01

    The present study was performed to determine the expression of porcine circovirus type 2 (PCV2) antigen in the ovarian tissue of naturally infected gilts. Ovarian tissues were obtained from 11 culled gilts. The ovarian tissues sections were divided into two groups according to PCV2 DNA detection using PCR. PCV2 antigen was assessed in the paraffin embedded ovarian tissue sections by immunohistochemistry. A total of 2,131 ovarian follicles (i.e., 1,437 primordial, 133 primary, 353 secondary and 208 antral follicles), 66 atretic follicles and 131 corpora lutea were evaluated. It was found that PCV2 antigen was detected in 280 ovarian follicles (i.e., 239 primordial follicles, 12 primary follicles, 10 secondary follicles and 19 antral follicles), 1 atretic follicles and 3 corpora lutea (P<0.05). PCV2 antigen was detected in primordial follicles more often than in secondary follicles, atretic follicles and corpora lutea (P<0.05). The detection of PCV2 antigen was found mainly in oocytes. PCV2 antigen was found in both PCV2 DNA positive and negative ovarian tissues. It can be concluded that PCV2 antigen is expressed in all types of the ovarian follicles and corpora lutea. Further studies should be carried out to determine the influence of PCV2 on porcine ovarian function and oocyte quality. PMID:26522687

  7. Assisted Ventilation.

    PubMed

    Dries, David J

    2016-01-01

    Controlled Mechanical Ventilation may be essential in the setting of severe respiratory failure but consequences to the patient including increased use of sedation and neuromuscular blockade may contribute to delirium, atelectasis, and diaphragm dysfunction. Assisted ventilation allows spontaneous breathing activity to restore physiological displacement of the diaphragm and recruit better perfused lung regions. Pressure Support Ventilation is the most frequently used mode of assisted mechanical ventilation. However, this mode continues to provide a monotonous pattern of support for respiration which is normally a dynamic process. Noisy Pressure Support Ventilation where tidal volume is varied randomly by the ventilator may improve ventilation and perfusion matching but the degree of support is still determined by the ventilator. Two more recent modes of ventilation, Proportional Assist Ventilation and Neurally Adjusted Ventilatory Assist (NAVA), allow patient determination of the pattern and depth of ventilation. Proposed advantages of Proportional Assist Ventilation and NAVA include decrease in patient ventilator asynchrony and improved adaptation of ventilator support to changing patient demand. Work of breathing can be normalized with these modes as well. To date, however, a clear pattern of clinical benefit has not been demonstrated. Existing challenges for both of the newer assist modes include monitoring patients with dynamic hyperinflation (auto-positive end expiratory pressure), obstructive lung disease, and air leaks in the ventilator system. NAVA is dependent on consistent transduction of diaphragm activity by an electrode system placed in the esophagus. Longevity of effective support with this technique is unclear.

  8. Fetal infections and antibody profiles in pigs naturally infected with porcine circovirus type 2 (PCV2)

    PubMed Central

    Gerber, Priscilla F.; Garrocho, Flávia M.; Lana, Ângela M.Q.; Lobato, Zélia I.P.

    2012-01-01

    The aim of this study was to describe early infections with porcine circovirus type 2 (PCV2) in naturally infected piglets and the piglets’ serologic profiles. A total of 20 sows (15 PCV2-vaccinated and 5 unvaccinated) and 100 newborn piglets were studied. Colostrum and serum of the sows and serum of the presuckling piglets were obtained on the day of parturition. Milk samples were collected on day 20 postpartum. Blood samples were taken and the piglets weighed on days 1, 20, 42, 63, and 84 postpartum. Colostrum and milk were evaluated for infectious PCV2 and for PCV2 total antibody (TA), neutralizing antibody (NA), and IgA. Serum samples were evaluated for PCV2 TA, NA, IgA, IgM, and DNA. The sows had high levels of TA and NA in serum and colostrum; however, 11 and 5, respectively, of the 20 colostrum and milk samples contained infectious PCV2. In the serum, PCV2 DNA and IgM were detected in 17 and 5, respectively, of the 20 sows. Nine piglets were born with PCV2 antibodies, which indicates in utero transmission of PCV2 after the period of immunocompetence (> 70 d of gestation). On day 1 postpartum, PCV2 DNA was detected in 29 of the 100 serum samples from the piglets. There was no difference between the weights of viremic and nonviremic piglets throughout the study. In conclusion, even on farms with sows that have high PCV2 antibody titers, vertical transmission of PCV2 may occur, resulting in piglet infection. PMID:22754093

  9. Astragalus polysaccharides attenuate PCV2 infection by inhibiting endoplasmic reticulum stress in vivo and in vitro

    PubMed Central

    Xue, Hongxia; Gan, Fang; Qian, Gang; Hu, Junfa; Hao, Shu; Xu, Jing; Chen, Xingxiang; Huang, Kehe

    2017-01-01

    This study explored the effects of Astragalus polysaccharide (APS) on porcine circovirus type 2 (PCV2) infections and its mechanism in vivo and vitro. First, fifty 2-week-old mice were randomly divided into five groups: a group without PCV2 infection and groups with PCV2 infections at 0, 100, 200 or 400 mg/kg APS treatments. The trial lasted for 28 days. The results showed that APS treatments at 200 and 400 mg/kg reduced the pathological injury of tissues, inhibited PCV2 infection and decreased glucose-regulated protein 78 (GRP78) and GADD153/CHOP gene mRNA and protein expression significantly (P < 0.05). Second, a study on endoplasmic reticulum stress mechanism was carried out in PK15 cells. APS treatments at 15 and 45 μg/mL significantly reduced PCV2 infection and GRP78 mRNA and protein expression (P < 0.05). Tunicamycin supplementation increased GRP78 mRNA and protein expression and significantly attenuated the APS-induced inhibition of PCV2 infection (P < 0.05). Tauroursodeoxycholic acid supplementation decreased GRP78 mRNA and protein expression and significantly inhibited PCV2 infection (P < 0.05). In addition, fifty 2-week-old mice were randomly divided into five groups: Con, PCV2, APS + PCV2, TM + PCV2 and TM + APS + PCV2. The results were similar to those in PK15 cells. Taken together, it could be concluded that APS suppresses PCV2 infection by inhibiting endoplasmic reticulum stress. PMID:28071725

  10. Mycoplasma hyopneumoniae bacterins and porcine circovirus type 2 (PCV2) infection: induction of postweaning multisystemic wasting syndrome (PMWS) in the gnotobiotic swine model of PCV2-associated disease.

    PubMed

    Krakowka, Steven; Ellis, John; McNeilly, Francis; Waldner, Cheryl; Rings, D Michael; Allan, Gordon

    2007-07-01

    Groups (5 to 15 per group) of gnotobiotic swine were infected oronasally with porcine circovirus type 2 (PCV2) at 3 days of age and then given 1 of 6 different commercial Mycoplasma hyopneumoniae (M. hyopneumoniae) bacterins as either a single dose (7 d of age, 1 application products) or 2 doses (7 and 21 d of age, 2 application product). Control groups received PCV2 alone (n = 9) or were infected with PCV2 and immunized twice with keyhole limpet hemocyanin (KLH) emulsified in incomplete Freund's adjuvant (ICFA) (n = 7). Five of 7 (71%) PCV2-infected piglets immunized with KLH/ICFA developed mild or overt PMWS, whereas none of 9 piglets infected with PCV2 alone developed PMWS. Five of 12 (42%) piglets vaccinated with a commercial bacterin containing mineral oil adjuvant developed PMWS following vaccination. None of the PCV2-infected piglets in the other bacterin-vaccinated groups developed PMWS in this model of PCV2-associated disease. This difference in prevalence of PMWS in piglets given the mineral oil-adjuvanted M. hyopneumoniae bacterin and the other M. hyopneumoniae bacterin vaccination groups was statistically significant (P < 0.05).

  11. Expression of antigenic epitopes of porcine reproductive and respiratory syndrome virus (PRRSV) in a modified live-attenuated porcine circovirus type 2 (PCV2) vaccine virus (PCV1-2a) as a potential bivalent vaccine against both PCV2 and PRRSV.

    PubMed

    Piñeyro, Pablo E; Kenney, Scott P; Giménez-Lirola, Luis G; Heffron, C Lynn; Matzinger, Shannon R; Opriessnig, Tanja; Meng, Xiang-Jin

    2015-12-02

    Co-infection of pigs in the field with porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) is common and poses a major concern in effective control of PCV2 and PRRSV. We previously demonstrated that insertion of foreign epitope tags in the C-terminus of PCV2 ORF2 produced infectious virions that elicited humoral immune responses against both PCV2 capsid and inserted epitope tags. In this study, we aimed to determine whether the non-pathogenic chimeric virus PCV1-2a, which is the basis for the licensed PCV2 vaccine Fostera PCV, can express PRRSV antigenic epitopes, thus generating dual immunity as a potential bivalent vaccine against both PCV2 and PPRSV. Four different linear B-cell antigenic epitopes of PRRSV were inserted into the C-terminus of the capsid gene of the PCV1-2a vaccine virus. We showed that insertion of 12 (PRRSV-GP2 epitope II, PRRSV-GP3 epitope I, and PRRSV-GP5 epitope I), and 14 (PRRSV-GP5 epitope IV) amino acid residues did not impair the replication of the resulting PCV1-2a-PRRSVEPI chimeric viruses in vitro. The four chimeric PCV1-2a viruses expressing PRRSV B-cell linear epitopes were successfully rescued and characterized. An immunogenicity study in pigs revealed that two of the four chimeric viruses, PCV1-2a-PRRSVEPIGP3IG and PCV1-2a-PRRSVEPIEPIGP5IV, elicited neutralizing antibodies against PRRSV VR2385 as well as PCV2 (strains PCV2a, PCV2b, and mPCV2b). The results have important implications for exploring the potential use of PCV1-2a vaccine virus as a live virus vector to develop bivalent MLVs against both PCV2 and PRRSV.

  12. Portable power supply for continuous mechanical ventilation during intrahospital transport of critically ill patients with ARDS.

    PubMed

    Barton, A C; Tuttle-Newhall, J E; Szalados, J E

    1997-08-01

    Patients with respiratory failure and poor pulmonary compliance requiring high levels of positive pressure ventilation are at high risk during intrahospital transportation. Most ICU ventilators currently do not have a built-in power supply. Manual bag-valve ventilation frequently is used but often without optimum mean airway pressures or minute ventilation guarantees. Transport ventilators also are limited in their ability to provide high positive end-expiratory pressure, variable inspiratory-expiratory ratios, or pressure-controlled ventilation. The 3M SARNS HELP (Hospital Emergency Limited Power) 115, a portable battery, provides continuous power to ICU ventilators and eliminates ventilator circuit interruption for the critical period of patient transportation.

  13. Diagnostic Relevance of Pressure-Controlled Discography

    PubMed Central

    Shin, Dong-Ah; Jung, Jae-Hyun; Shin, Dong-Gyu; Lee, Jung-Ok

    2006-01-01

    Discogenic pain is a leading cause of chronic low back pain. The authors investigated the efficacy of pressure-controlled discography to determine its role in clinical decision-making for the management of patients with discogenic pain. Pressure-controlled discography was performed in 21 patients (51 discs) with pain-provocation, followed by post-discography computerized tomography scans. Pain response was classified as positive response and negative response, and measured with visual analog scale scores. Discographic findings were graded by the modified Dallas discogram scale. Elastance, pain provocation on intradiscal pressure, pressure and volume of initial pain response, and pain response intensity were statistically analyzed. Elastance showed significant differences between Grade 0 and Grade 4 & 5. Decreased elastance with positive pain response group was a good indicator to imply that disc degeneration presumably is a pain generator. Results of pain response were well correlated with intradiscal pressure but not with the amount of injected volume. Among 31 discs of Grade 4 and 5, 74% showed negative pain response and 26% showed positive response. It was concluded that pressure-controlled discography was useful to diagnose discogenic pain and excellent guide in decision-making for spinal operations. PMID:17043428

  14. Porcine circovirus type 2 (PCV2) enteric disease: an independent condition or part of the systemic disease?

    PubMed

    Baró, J; Segalés, J; Martínez, J

    2015-03-23

    Intestinal disorders in growing and finishing pigs have been associated with several infectious agents, including Porcine circovirus type 2 (PCV2). This virus has been mainly related with PCV2-systemic disease (PCV2-SD); nevertheless, some authors have suggested a possible restricted intestinal infection of this virus associated with enteric clinical signs. This condition has been referred as PCV2-enteric disease (PCV2-ED). The present study analysed retrospectively, from a pathological point of view, the relation between intestinal disorders and PCV2 infection in nursery and growing-finishing pigs. Among the 96 selected pigs suffering from enteric disease and submitted for necropsy between 1998 and 2011, the most prevalent enteric lesions were catarrhal enteritis/colitis (77.1%), followed by fibrinous lesions (11.5%), granulomatous inflammation (4.2%) and other lesions such as haemorrhages or ulceration (4.2%). Seventy-two pigs (75%) were positive for PCV2 by in situ hybridization (ISH). Among positive pigs for PCV2 ISH, 39 animals suffered from PCV2-SD and 33 had no lymphoid lesions but low amount of viral nucleic acid in several lymphoid tissues, therefore, these animals did not qualify for PCVD-ED. In conclusion, all animals with enteric disorders that were positive to PCV2 by ISH had evidence of viral systemic infection. These results suggest that PCV2-ED is probably a negligible condition and PCV2 mainly contributes to enteric clinical disorders in relation to PCV2-SD occurrence.

  15. Demand Controlled Ventilation and Classroom Ventilation

    SciTech Connect

    Fisk, William J.; Mendell, Mark J.; Davies, Molly; Eliseeva, Ekaterina; Faulkner, David; Hong, Tienzen; Sullivan, Douglas P.

    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.

  16. Oral application of freeze-dried yeast particles expressing the PCV2b Cap protein on their surface induce protection to subsequent PCV2b challenge in vivo

    PubMed Central

    Patterson, Robert; Eley, Thomas; Browne, Christopher; Martineau, Henny M.; Werling, Dirk

    2015-01-01

    Porcine circovirus type 2 (PCV2) is now endemic in every major pig producing country, causing PCV-associated disease (PCVAD), linked with large scale economic losses. Current vaccination strategies are based on the capsid protein of the virus and are reasonably successful in preventing PCVAD but fail to induce sterile immunity. Additionally, vaccinating whole herds is expensive and time consuming. In the present study a “proof of concept” vaccine trial was employed to test the effectiveness of powdered freeze-dried recombinant Saccharomyces cerevisiae yeast stably expressing the capsid protein of PCV2b on its surface as an orally applied vaccine. PCV2-free pigs were given 3 doses of vaccine or left un-vaccinated before challenge with a defined PCV2b strain. Rectal temperatures were measured and serum and faeces samples were collected weekly. At the end of the study, pigs were euthanized, tissue samples taken and tested for PCV2b load by qPCR and immunohistochemistry. The peak of viraemia in sera and faeces of unvaccinated pigs was higher than that of vaccinated pigs. Additionally more sIgA was found in faeces of vaccinated pigs than unvaccinated. Vaccination was associated with lower serum concentrations of TNFα and IL-1β but higher concentrations of IFNα and IFNγ in comparison to the unvaccinated animals. At the end of the trial, a higher viral load was found in several lymphatic tissues and the ileum of unvaccinated pigs in comparison to vaccinated pigs. The difference between groups was especially apparent in the ileum. The results presented here demonstrate a possible use for recombinant S. cerevisiae expressing viral proteins as an oral vaccine against PCV2. A powdered freeze-dried recombinant S. cerevisiae used as an oral vaccine could be mixed with feed and may offer a cheap and less labour intensive alternative to inoculation with the additional advantage that no cooling chain would be required for vaccine transport and storage. PMID:26476879

  17. Oral application of freeze-dried yeast particles expressing the PCV2b Cap protein on their surface induce protection to subsequent PCV2b challenge in vivo.

    PubMed

    Patterson, Robert; Eley, Thomas; Browne, Christopher; Martineau, Henny M; Werling, Dirk

    2015-11-17

    Porcine circovirus type 2 (PCV2) is now endemic in every major pig producing country, causing PCV-associated disease (PCVAD), linked with large scale economic losses. Current vaccination strategies are based on the capsid protein of the virus and are reasonably successful in preventing PCVAD but fail to induce sterile immunity. Additionally, vaccinating whole herds is expensive and time consuming. In the present study a "proof of concept" vaccine trial was employed to test the effectiveness of powdered freeze-dried recombinant Saccharomyces cerevisiae yeast stably expressing the capsid protein of PCV2b on its surface as an orally applied vaccine. PCV2-free pigs were given 3 doses of vaccine or left un-vaccinated before challenge with a defined PCV2b strain. Rectal temperatures were measured and serum and faeces samples were collected weekly. At the end of the study, pigs were euthanized, tissue samples taken and tested for PCV2b load by qPCR and immunohistochemistry. The peak of viraemia in sera and faeces of unvaccinated pigs was higher than that of vaccinated pigs. Additionally more sIgA was found in faeces of vaccinated pigs than unvaccinated. Vaccination was associated with lower serum concentrations of TNFα and IL-1β but higher concentrations of IFNα and IFNγ in comparison to the unvaccinated animals. At the end of the trial, a higher viral load was found in several lymphatic tissues and the ileum of unvaccinated pigs in comparison to vaccinated pigs. The difference between groups was especially apparent in the ileum. The results presented here demonstrate a possible use for recombinant S. cerevisiae expressing viral proteins as an oral vaccine against PCV2. A powdered freeze-dried recombinant S. cerevisiae used as an oral vaccine could be mixed with feed and may offer a cheap and less labour intensive alternative to inoculation with the additional advantage that no cooling chain would be required for vaccine transport and storage.

  18. Comparison of sow and/or piglet vaccination of 3 commercial porcine circovirus type 2 (PCV2) single-dose vaccines on pigs under experimental PCV2 challenge.

    PubMed

    Oh, Yeonsu; Seo, Hwi Won; Park, Changhoon; Chae, Chanhee

    2014-08-27

    The objective of the present study was to compare the effect of sow and/or piglet vaccination regimen by three commercial porcine circovirus type 2 (PCV2) vaccines on pigs experimentally challenged with PCV2 at 84 days of age based on immunological, virological, and pathological evaluation. One hundred and nineteen piglets born to vaccinated or non-vaccinated sows were divided into 17 groups. A portion of the pigs with or without passively acquired immunity was vaccinated at 21 or 49 days of age. Regardless of the PCV2 vaccine, the combination of sow and pig (49 days of age) vaccinations significantly (P<0.05) reduced PCV2 viremia, induced higher log2 transformed neutralizing antibody titers, and resulted in higher proportion of CD4(+)CD8(+)IFN-γ(+) lymphocyte subsets than the sow vaccination alone, the pig (21 or 49 days of age) vaccination alone, and the combination of sow and pig (21 days of age) vaccinations at various days post challenge. The results showed a significant negative correlation between maternally derived antibodies at the day of vaccination and the increment of antibody titers to PCV2 at 28 days post vaccination in the combination of sow and pig (21 days of age) vaccinations but not the combination of sow and pig (49 days of age) vaccinations. The combination of sow and pig (49 days of age) vaccinations could be more effective for controlling PCV2 infection if PCV2 the infection occurs during the growing-finishing period in herds. Optimal vaccination strategies must balance the advantage of delayed vaccination with the need to induce immunity prior to exposure to pathogens under field conditions.

  19. Efficacy of parenteral vaccination against porcine circovirus type 2 (PCV2) in seropositive piglets.

    PubMed

    Gamage, Lakshman N A; McIntosh, Kathleen A; Parker, Sarah; Harding, John; Krakowka, Steven; Ellis, John

    2012-10-01

    This study investigated if parenteral administration of a prototype adjuvanted vaccine against porcine circovirus type 2 (PCV2) could override maternally derived antibodies and induce acquired immunity in young piglets. Piglets with high levels of maternal PCV2 antibodies at 1 wk of age were randomly grouped into vaccinates and controls on the basis of body weight and inoculated with the vaccine or a control preparation twice, with an interval of 3 wk. Both groups were challenged 3 wk after the booster vaccination and euthanized 3 wk after challenge. The pigs were evaluated for clinical disease, histologic lesions in sections of gastric and left inguinal lymph nodes stained with hematoxylin and eosin, and the amount of PCV2 antigen in the lymph nodes by immunohistochemical study. The PCV2 antibody titers were monitored by competitive enzyme-linked immunosorbent assay throughout the experiment. The vaccinates showed significantly less decline (P < 0.05) in PCV2 antibody titers after the booster vaccination. Clinical disease did not develop in any of the piglets. The vaccinates and controls did not differ in either histologic lesions or amount of PCV2 antigen in the lymph nodes. This study demonstrated some evidence of priming of young piglets in the presence of maternal antibodies. Further studies are recommended to determine the optimum concentration of PCV2 antigen and a suitable adjuvant for the vaccine to achieve the full potential of the strategy of inducing acquired immunity in young piglets that have maternally derived antibodies.

  20. Comparative efficacy of commercial Mycoplasma hyopneumoniae and porcine circovirus 2 (PCV2) vaccines in pigs experimentally infected with M. hyopneumoniae and PCV2.

    PubMed

    Kim, D; Kim, C H; Han, K; Seo, H W; Oh, Y; Park, C; Kang, I; Chae, C

    2011-04-12

    The efficacies of two commercial Mycoplasma hyopneumoniae bacterins and porcine circovirus 2 (PCV2) vaccines were compared in conventional pigs immunized at different ages based on humoral response, pathological observation, and growth performance from birth to finishing (175 days of age) using a M. hyopneumoniae and PCV2 co-infection challenge model. One-week-old pigs (n=110) were randomly assigned to five groups: three vaccinated and challenged (VC), and one each of non-vaccinated and challenged (NVC) and negative control. A significant difference was found in the number of genomic copies of M. hyopneumoniae in nasal swabs and PCV2 in serum samples, the average daily weight gain (gram/pig/day) between 63 and 133 dpi, gross and histopathological lung lesion scores, histopathological lymph node lesion scores, and the immunohistochemical analysis of PCV2 among the three VC groups. The single dose schedule for M. hyopneumoniae bacterins and PCV2 vaccines have the advantages of (i) improving daily weight gain (122.4%) and slaughter weight (120.5%), and (ii) reducing the incidence of clinical signs and lung and lymph node lesions.

  1. Blood pressure control for diabetic retinopathy

    PubMed Central

    Do, Diana V; Wang, Xue; Vedula, Satyanarayana S; Marrone, Michael; Sleilati, Gina; Hawkins, Barbara S; Frank, Robert N

    2015-01-01

    Background Diabetic retinopathy is a common complication of diabetes and a leading cause of visual impairment and blindness. Research has established the importance of blood glucose control to prevent development and progression of the ocular complications of diabetes. Simultaneous blood pressure control has been advocated for the same purpose, but findings reported from individual studies have supported varying conclusions regarding the ocular benefit of interventions on blood pressure. Objectives The primary aim of this review was to summarize the existing evidence regarding the effect of interventions to control or reduce blood pressure levels among diabetics on incidence and progression of diabetic retinopathy, preservation of visual acuity, adverse events, quality of life, and costs. A secondary aim was to compare classes of anti-hypertensive medications with respect to the same outcomes. Search methods We searched a number of electronic databases including CENTRAL as well as ongoing trial registries. We last searched the electronic databases on 25 April 2014. We also reviewed reference lists of review articles and trial reports selected for inclusion. In addition, we contacted investigators of trials with potentially pertinent data. Selection criteria We included in this review randomized controlled trials (RCTs) in which either type 1 or type 2 diabetic participants, with or without hypertension, were assigned randomly to intense versus less intense blood pressure control, to blood pressure control versus usual care or no intervention on blood pressure, or to different classes of anti-hypertensive agents versus placebo. Data collection and analysis Pairs of review authors independently reviewed titles and abstracts from electronic and manual searches and the full text of any document that appeared to be relevant. We assessed included trials independently for risk of bias with respect to outcomes reported in this review. We extracted data regarding trial

  2. Underwater space suit pressure control regulator

    NASA Technical Reports Server (NTRS)

    Aldrich, B. R.; Cooper, C. R.; Rasquin, J. R. (Inventor)

    1973-01-01

    A device is reported for regulating the pneumatic pressure in a ventilated space suit relative to the pressure imposed on the suit when being worn by a person underwater to simulate space environment for testing and experimentation. A box unit located on the chest area of the suit comprises connections for suit air supply and return lines and carries a regulator valve that stabilizes the air pressure differential between the inside and outside of the suit. The valve and suit pressure is controlled by the suit occupant and the valve includes a mechanism for quickly dumping the suit pressure in case of emergency. Pressure monitoring and relief devices are also included in the box unit.

  3. Ventilation Model

    SciTech Connect

    V. Chipman

    2002-10-05

    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 post-closure analyses. The Ventilation Model report was initially developed to analyze the effects of preclosure continuous ventilation in the Engineered Barrier System (EBS) emplacement drifts, and to provide heat removal data to support EBS design. Revision 00 of the Ventilation Model included documentation of the modeling results from the ANSYS-based heat transfer model. The purposes of Revision 01 of the Ventilation Model are: (1) To validate the conceptual model for preclosure ventilation of emplacement drifts and verify its numerical application in accordance with new procedural requirements as outlined in AP-SIII-10Q, Models (Section 7.0). (2) To satisfy technical issues posed in KTI agreement RDTME 3.14 (Reamer and Williams 2001a). Specifically to demonstrate, with respect to the ANSYS ventilation model, the adequacy of the discretization (Section 6.2.3.1), and the downstream applicability of the model results (i.e. wall heat fractions) to initialize post

  4. Ventless pressure control of cryogenic storage tanks

    NASA Astrophysics Data System (ADS)

    Barsi, Stephen

    Future operations in space exploration will require the ability to store cryogenic liquids for long durations. During storage, the tanks may self-pressurize due to heat leaks from the ambient environment. When heat leaks into the tank, the cryogenic liquid vaporizes causing the ullage pressure to rise. Being able to effectively control tank pressure will make these long duration storage concepts feasible. One way to control tank pressure involves the use of a subcooled axial liquid jet to both thermally destratify the bulk liquid and remove energy from the tank. In this dissertation, the effectiveness of using subcooled jet mixing as a pressure control scheme is analyzed by performing a small-scale experiment in a normal gravity environment with a refrigerant. Following a period of self-pressurization, the jet's speed and degree of subcooling are parametrically varied so that relevant trends can be identified. Experimental results show that mixing the bulk liquid is not sufficient to control pressure. To sustain any pressure reduction, subcooling the mixing jet is necessary. The rate of pressure reduction is greater for increased jet speeds and subcooling. Analytical and computational models were developed in order to predict the pressurization behavior. Model comparisons reveal that generally a thermodynamic model underpredicts the self-pressurization and depressurization rates. The lack of agreement is primarily attributed to the homogeneity assumption inherent in the model. To improve model predictions, a zonal model is developed which relaxes the global homogeneity assumption. Comparisons between the experimental data and the zonal model predictions are excellent for moderate to high jet flow rates. For slower jet speeds, buoyant flow in the bulk liquid adversely affects the effectiveness of a subcooled mixing jet and a more detailed computational model is required to capture this intraphase phenomena.

  5. A pressure control analysis of cryogenic storage systems

    NASA Technical Reports Server (NTRS)

    Lin, C.-S.; Vandresar, N. T.; Hasan, M. M.

    1991-01-01

    Self-pressurization of cryogenic storage tanks due to heat leak through the thermal protection system is examined along with the performance of various pressure control technologies for application in microgravity environments. Methods of pressure control such as fluid mixing, passive thermodynamic venting, and active thermodynamic venting are analyzed using the homogeneous thermodynamic model. Simplified equations suggested may be used to characterize the performance of various pressure control systems and to design space experiments.

  6. International trades, local spread and viral evolution: the case of porcine circovirus type 2 (PCV2) strains heterogeneity in Italy.

    PubMed

    Franzo, Giovanni; Tucciarone, Claudia M; Dotto, Giorgia; Gigli, Alessandra; Ceglie, Letizia; Drigo, Michele

    2015-06-01

    Porcine circovirus type 2 is one of the most widespread and economically relevant infections of swine. Four genotypes have been recognized, but currently, only three (PCV2a, PCV2b and PCV2d) are effectively circulating. The widespread livestock trade and rapid viral evolution have contributed to determining the high heterogeneity of PCV2 and the dispersal of potentially more virulent strains. Italian swine farming and the related processing industry are relevant in the national economy. Despite the noteworthy losses associated with direct and control measure costs, no data are currently available on the molecular epidemiology of PCV2 in Italy. Our study, which was intended to fill this gap, considered 75 completed genome PCV2 sequences, which were obtained from samples collected from the highly densely populated area of Northern Italy between 2007 and 2014. Phylogenetic analysis and comparison with reference sequences demonstrated the co-circulation, with different prevalences, of PCV2a, PCV2b and PCV2d within the national borders, with PCV2b being the most prevalent. Recombination between different genotypes was also proven to be frequent. Phylogeographic analysis demonstrated that the marked variability of Italian PCV2 strains can be attributable to multiple introduction events. The comparison of the phylogenetic analysis results, the location of different haplotypes and the international commercial routs of live pigs allow the speculation of several links as well as the role of Italy as both an importer and exporter of PCV2 haplotypes, mainly from and to European and Asian countries. A similarly intricate contact network was demonstrated within national borders, with different haplotypes being detected in the same province and different provinces harbouring the same haplotype. Overall, this paper represents the first description of PCV2 in Italy and demonstrates that the high variability of circulating Italian strains is due to multiple introduction events, wide

  7. Effect of sow vaccination against porcine circovirus type 2 (PCV2) on virological profiles in herds with or without PCV2 systemic disease

    PubMed Central

    Lopez-Rodriguez, Alfonso; Dewulf, Jeroen; Meyns, Tom; Del-Pozo-Sacristán, Rubén; Andreoni, Christine; Goubier, Anne; Chapat, Ludivine; Charreyre, Catherine; Joisel, François; Maes, Dominiek

    2016-01-01

    We investigated porcine circovirus type 2 (PCV2) virological profiles in herds affected (PCVAD-AH, n = 5) or non-affected (PCVAD-NAH, n = 4) by PCV2-associated diseases (PCVAD), before and after 1 y of PCV2 gilt and sow vaccination. Fresh feces from the floor (5 pens/age/farm) and 5 blood samples (1/pen) were collected at 3, 9, 15, 21 wk. Individual feces and blood samples were collected from 5 gilts and 15 sows. Sampling was repeated 1 y after vaccination. Quantitative PCR on feces, PCV2 antibodies in blood serum and cell-mediated immunity were investigated. Before vaccination, pigs of PCVAD-AH had higher viral load in feces (9 and 15 wk), lower IgG and higher IgM (3 wk) and lower lymphocyte counts (9 and 15 wk) suggesting immunosuppression. Vaccination reduced viral load in growers, increased IgG (3 wk) suggesting improved maternal immunity, reduced IgM (3 wk), increased total antibody titers in sows and increased CD79a cells in the pigs. PMID:27247462

  8. Comparison of Four Commercial One-Dose Porcine Circovirus Type 2 (PCV2) Vaccines Administered to Pigs Challenged with PCV2 and Porcine Reproductive and Respiratory Syndrome Virus at 17 Weeks Postvaccination To Control Porcine Respiratory Disease Complex under Korean Field Conditions

    PubMed Central

    Park, Changhoon; Seo, Hwi Won; Han, Kiwon

    2014-01-01

    Under Korean field conditions, coinfection with porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) is most commonly observed in porcine respiratory disease complex (PRDC). Despite the wide use of PCV2 vaccination, PRDC remains a serious respiratory problem. Thus, the objective of this study was to determine and compare the efficacy of 4 one-dose PCV2 vaccines on 3-week-old pigs with an experimental PCV2-PRRSV challenge at 17 weeks postvaccination. Regardless of which commercial PCV2 vaccine was used, the vaccination of piglets at 3 weeks of age was efficacious against cochallenge of PCV2 and PRRSV, on the basis of growth performance and PCV2-associated lesions. However, the inactivated chimeric PCV1-2 and the PCV2 vaccines induced higher PCV2-specific neutralizing antibody (NA) titers and PCV2-specific gamma interferon-secreting cells and lower PCV2 viremia levels than the two PCV2 subunit vaccines. The vaccination of piglets against PCV2 at 3 weeks of age was effective in reducing PCV2 viremia and PCV2-associated lesions during the finishing period, which is an age at which pigs are frequently affected by PRDC caused by coinfection with PCV2 and PRRSV under Korean field conditions. PMID:24403524

  9. Liquid ventilation

    PubMed Central

    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. PMID:25886321

  10. [Mechanical ventilator].

    PubMed

    Kimura, Akio; Hashimoto, S

    2009-07-01

    The development of the computer technology brought reform in the field of medical equipment. Originally the mechanical ventilator was an instrument only as for running by pressure and the tool that let you breathe. However, it has a function to assist a measurement (tidal volume, peek pressure, etc.) and to wean from a ventilator. There is a case to use a mechanical ventilator for after a chest surgical operation. After the operation without the complication, it seems that there is not the special administration. However, special respiratory management is necessary in case of chronic respiratory failure and acute lung injury, acute respiratory distress syndrome. Therefore I introduce a method to use a respirator after an operation in our institution.

  11. Porcine circovirus type 2 (PCV2) infections: clinical signs, pathology and laboratory diagnosis.

    PubMed

    Segalés, Joaquim

    2012-03-01

    Clinical signs and pathological features are still the corner-stones to suspect and diagnose overt disease associated with PCV2 infection. The clinico-pathological scope of this viral infection has been expanded over time. From the initial description of postweaning multisystemic wasting syndrome, some enteric, respiratory and reproductive disorders have been subsequently linked with PCV2. Porcine dermatitis and nephropathy syndrome, an immunocomplex disease, has also been associated with infection by this virus. All together, these conditions have been grouped under the name of porcine circovirus diseases (PCVD) or porcine circovirus associated diseases (PCVAD). The precise mechanisms by which a PCV2 infected pig develops a PCV2 subclinical infection or a clinical PCVD/PCVAD are still to be fully elucidated, but inferences based upon clinical, gross and histologic findings from field cases of disease have been useful to suggest the pathogenesis of this viral infection. The objective of the present review is to update the current knowledge on the clinical and pathological scope of PCV2 infections, as well as on their diagnosis. Moreover, a proposal on a unified PCVD/PCVAD terminology and clearly defined diagnostic criteria for these conditions are also given.

  12. Clonal evolution leading to maintenance of antibiotic resistance rates among colonizing Pneumococci in the PCV7 era in Portugal.

    PubMed

    Simões, Alexandra S; Pereira, Liliana; Nunes, Sónia; Brito-Avô, António; de Lencastre, Hermínia; Sá-Leão, Raquel

    2011-08-01

    The introduction of the seven-valent pneumococcal conjugate vaccine (PCV7) in Portugal led to extensive serotype replacement among carriers of pneumococci, with a marked decrease of PCV7 types. Although antimicrobial resistance was traditionally associated with PCV7 types, no significant changes in the rates of nonsusceptibility to penicillin, resistance to macrolides, or multidrug resistance were observed. This study aimed to investigate the mechanisms leading to maintenance of antimicrobial resistance, despite marked serotype replacement. We compared, through molecular typing, 252 antibiotic-resistant pneumococci recovered from young carriers in 2006 and 2007 (era of high PCV7 uptake) with collections of isolates from 2002 and 2003 (n=374; low-PCV7-uptake era) and 1996 to 2001 (n=805; pre-PCV7 era). We observed that the group of clones that has accounted for antimicrobial resistance since 1996 is essentially the same as the one identified in the PCV7 era. The relative proportions of such clones have, however, evolved substantially overtime. Notably, widespread use of PCV7 led to an expansion of two Pneumococcal Molecular Epidemiology Network (PMEN) clones expressing non-PCV7 capsular variants of the original strains: Sweden(15A)ST63 (serotypes 15A and 19A) and Denmark(14)ST230 (serotypes 19A and 24F). These variants were already in circulation in the pre-PCV7 era, although they have now become increasingly abundant. Emergence of novel clones and de novo acquisition of resistance contributed little to the observed scenario. No evidence of capsular switch events occurring after PCV7 introduction was found. In the era of PCVs, antimicrobial resistance remains a problem among the carried pneumococci. Continuous surveillance is warranted to evaluate serotype and clonal shifts leading to maintenance of antimicrobial resistance.

  13. [Development of the remote hydraulic pressure control injection].

    PubMed

    Wang, Di-le; Li, Ming-jie; He, Tao; Zheng, Zhi; Duan, Xin; Zheng, Ying-jian

    2009-01-01

    This paper introduced the work principle, execution, use and major characteristics of the remote hydraulic pressure control injection. Using Pascal principle, it is more accurate, convenient, cheap and safe. It could be used in all the fields of the medicine.

  14. Investigation and validation of the role of a QTL on SSC12 in PCV2b viremia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Porcine circovirus type 2 (PCV2) is known to modulate immune response leading to a susceptibility to Porcine Circovirus Associated Diseases (PCVAD) with an impact on growth and mortality. Our previous GWAS of PCV2b experimentally infected pigs uncovered two QTL that explain 14% of the genetic variat...

  15. Concurrent porcine circovirus type 2a (PCV2a) or PCV2b infection increases the rate of amino acid mutations of porcine reproductive and respiratory syndrome virus (PRRSV) during serial passages in pigs.

    PubMed

    Yin, Shuang-Hui; Xiao, Chao-Ting; Gerber, Priscilla F; Beach, Nathan M; Meng, Xiang-Jin; Halbur, Patrick G; Opriessnig, Tanja

    2013-12-26

    Porcine reproductive and respiratory syndrome virus (PRRSV) has a high degree of genetic and antigenic variability. The purpose of this study was to determine if porcine circovirus type 2 (PCV2) infection increases genetic variability of PRRSV during serial passages in pigs and to determine if there is a difference in the PRRSV mutation rate between pigs concurrently infected with PCV2a or PCV2b. After 8 consecutive passages of PRRSV alone (group 1), PRRSV with PCV2a (group 2), or PCV2b (group 3) in pigs, the sequences of PRRSV structural genes for open reading frame (ORF) 5, ORF6, ORF7 and the partial non-structural protein gene (Nsp) 2 were determined. The total number of identified amino acid mutations in ORF5, ORF6, ORF7 and Nsp2 sequences was 30 for PRRSV infection only, 63 for PRRSV/PCV2a concurrent infection, and 77 for PRRSV/PCV2b concurrent infection when compared with the original VR2385 virus used to infect the passage 1 pigs. Compared to what occurred in pigs infected with PRRSV only, the mutation rates in ORF5 and ORF6 were significantly higher for concurrent PRRSV/PCV2b infected pigs. The PRRSV/PCV2a pigs had a significantly higher mutation rate in ORF7. The results from this study indicated that, besides ORF5 and Nsp2, the PRRSV structural genes ORF6 and ORF7 were shown to mutate at various degrees when the PRRSV was passaged over time in vivo. Furthermore, a significantly higher mutation rate of PRRSV was observed when pigs were co-infected with PCV2 highlighting the importance of concurrent infections on PRRSV evolution and control.

  16. A review of economic evaluations of 13-valent pneumococcal conjugate vaccine (PCV13) in adults and the elderly

    PubMed Central

    Dirmesropian, S; Wood, JG; MacIntyre, CR; Newall, AT

    2015-01-01

    The 13-valent pneumococcal conjugated vaccine (PCV13) is already recommended for some adult groups and is being considered for wider use in many countries. In order to identify the strengths and limitations of the existing economic evaluation studies of PCV13 in adults and the elderly a literature review was conducted. The majority of the studies identified (9 out of 10) found that PCV13 was cost-effective in adults and/or the elderly. However, these results were based on assumptions that could not always be informed by robust evidence. Key uncertainties included the efficacy of PCV13 against non-invasive pneumonia and the herd immunity effect of childhood vaccination programs. Emerging trial evidence on PCV13 in adults from the Netherlands offers the ability to parameterize future economic evaluations with empirical efficacy data. However, it is important that these estimates are used thoughtfully when they are transferred to other settings. PMID:25933180

  17. Optimization on Preparation Conditions of Salidroside Liposome and Its Immunological Activity on PCV-2 in Mice

    PubMed Central

    Feng, Yibo; Zhao, Xiaojuan; Lv, Fang; Zhang, Jinqiu; Deng, Bihua; Zhao, Yanhong; Hu, Yuanliang; Wang, Deyun; Liu, Jiaguo; Lu, Yu; Bo, Ruonan; Liu, Zhenguang

    2015-01-01

    The aim of this study was to optimize the preparation conditions of salidroside liposome with high encapsulation efficiency (EE) and to study the immunological enhancement activity of salidroside liposome as porcine circovirus type 2 virus (PCV-2) vaccine adjuvant. Response surface methodology (RSM) was selected to optimize the conditions for the preparation of salidroside liposome using Design-Expert V8.0.6 software. Three kinds of salidroside liposome adjuvants were prepared to study their adjuvant activity. BALB/c mice were immunized with PCV-2 encapsulated in different kinds of salidroside liposome adjuvants. The PCV-2-specific IgG in immunized mice serum was determined with ELISA. The results showed that when the concentration of ammonium sulfate was 0.26 mol·L−1, ethanol volume 6.5 mL, temperature 43°C, ethanol injection rate 3 mL·min−1, and salidroside liposome could be prepared with high encapsulation efficiency of 94.527%. Salidroside liposome as adjuvant could rapidly induce the production of PCV-2-specific IgG and salidroside liposome I adjuvant proved to provide the best effect among the three kinds of salidroside liposome adjuvants. PMID:25878712

  18. Pressure versus volume controlled modes in invasive mechanical ventilation.

    PubMed

    Garnero, A J; Abbona, H; Gordo-Vidal, F; Hermosa-Gelbard, C

    2013-05-01

    The first generation of mechanical ventilators were controlled and cycled by pressure. Unfortunately, they did not allow control of the delivered tidal volume under changes in the dynamics of the respiratory system. This led to a second generation of ventilators that allowed volume control, hence favoring the ventilatory strategy based on normalization of the arterial gases. Studies conducted in the 1980s which related lung injury to the high ventilator pressures utilized while treating acute respiratory distress syndrome patients renewed interest in pressure-controlled mechanical ventilation. In addition, new evidence became available, leading to the development of pulmonary protective strategies aiming at preventing the progression of ventilator-induced lung injury. This review provides a detailed description of the control of pressure or volume using certain ventilatory modes, and offers a general view of their advantages and disadvantages, based on the latest available evidence.

  19. Efficacy of a new bivalent vaccine of porcine circovirus type 2 and Mycoplasma hyopneumoniae (Fostera™ PCV MH) under experimental conditions.

    PubMed

    Park, Changhoon; Jeong, Jiwoon; Choi, Kyuhyung; Chae, Chanhee

    2016-01-04

    The objective of this study was to evaluate the efficacy of a new bivalent vaccine (Fostera™ PCV MH, Zoetis) of porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae in growing pigs under experimental conditions. A total of 80 pigs were randomly divided into 8 groups (10 pigs per group). The pigs were administered the bivalent vaccine intramuscularly as a 2.0 mL dose at 21 days of age based on the manufacturer's instructions. Three weeks after vaccination, the pigs were inoculated with either PCV2 (intranasal route) or M. hyopneumoniae (intratracheal route) or both. Regardless of the type of inoculation, vaccinated pigs after challenge exhibited effective reduction of clinical signs, PCV2 viremia levels and mycoplasma nasal shedding, and lung and lymphoid lesion when compared to unvaccinated challenged pigs. Vaccinated challenged pigs had significantly higher (P<0.05) levels of PCV2-specific neutralizing antibodies, and numbers of PCV2-and M. hyopneumoniae-specific interferon-γ secreting cells compared to unvaccinated challenged pigs. This study demonstrates that the bivalent vaccine is able to protect pigs against either PCV2 or M. hyopneumoniae infection or both based on clinical, microbiological, immunological, and pathological evaluation.

  20. Baculovirus as a PRRSV and PCV2 bivalent vaccine vector: baculovirus virions displaying simultaneously GP5 glycoprotein of PRRSV and capsid protein of PCV2.

    PubMed

    Xu, Xin-Gang; Wang, Zhi-Sheng; Zhang, Qi; Li, Zhao-Cai; Ding, Li; Li, Wei; Wu, Hung-Yi; Chang, Ching-Dong; Lee, Long-Huw; Tong, De-Wen; Liu, Hung-Jen

    2012-02-01

    The GP5 glycoprotein of PRRSV is the main target for inducing neutralizing antibodies and protective immunity in the natural host. The capsid (Cap) protein is the major immunogenic protein and associated with the production of PCV2-specific neutralizing antibodies. In the present study, one genetic recombinant baculovirus BacSC-Dual-GP5-Cap was constructed. This virus displays simultaneously histidine-tagged GP5 and Cap proteins with the baculovirus glycoprotein gp64 TM and CTD on the virion surface as well as the surface of the virus-infected cells. After infection, the GP5 and Cap proteins were expressed and anchored simultaneously on the plasma membrane of Sf-9 cells, as revealed by Western blot and confocal microscopy. This report demonstrated first that both GP5 and Cap proteins were displayed successfully on the viral surface, revealed by immunogold electron microscopy. Vaccination of swine with recombinant baculovirus BacSC-Dual-GP5-Cap elicited significantly higher GP5 and Cap ELISA antibody titers in swine than the control groups. Virus neutralization test also showed that serum from the BacSC-Dual-GP5-Cap treated swine had significant levels of virus neutralization titers. Lymphocyte proliferation responses could be induced in swine immunized with BacSC-Dual-GP5-Cap than the control groups. These findings demonstrate that the BacSC-Dual-GP5-Cap bivalent subunit vaccine can be a potential vaccine against PRRSV and PCV2 infections.

  1. 142. STANDBY PRESSURE CONTROL UNIT FOR FUEL AND LIQUID OXYGEN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    142. STANDBY PRESSURE CONTROL UNIT FOR FUEL AND LIQUID OXYGEN IN SOUTHWEST PORTION OF CONTROL ROOM (214), LSB (BLDG. 751), FACING WEST - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

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

    PubMed

    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

  3. Quantification of porcine circovirus type 2 (PCV-2) within- and between-pen transmission in pigs.

    PubMed

    Andraud, Mathieu; Grasland, Béatrice; Durand, Benoît; Cariolet, Roland; Jestin, André; Madec, François; Rose, Nicolas

    2008-01-01

    PCV-2 within- and between-pen transmission was quantified by estimating the daily transmission rate beta and the basic reproduction ratio (R(0)) using a stochastic SEIR (Susceptible, Exposed, Infectious, Removed) model fitted on experimental data. Within-pen transmission was quantified by using four groups of eight SPF (specific pathogen-free) pigs (four infected and four susceptible pigs having direct contact). Between-pen transmission was studied in two groups of 16 SPF pigs (eight infected and eight susceptible pigs having indirect contact (10 cm distance)). Pigs were monitored twice a week (blood samples) and were tested for PCV-2 antibodies (ELISA test) and viral genome load in sera (real-time PCR). Transmission parameters beta(within) and beta(between) were estimated using a maximum likelihood method and the duration of infectiousness, to compute R(0), was estimated with a parametric survival model. Different assumptions were made to determine the end of infectiousness (seroconversion, seroconversion and decline in viral genome load, permanent infectiousness). R(0[within]) (8.9 (5.1-15.4)) was greater when the end of infectiousness was assumed to be related to both seroconversion and a decline of PCV-2 genome load in sera (average duration of infectiousness = 32 days) compared with only seroconversion as the indicator of recovery (R(0[within]) = 5.5 (3.3-9.0)). Whatever the assumption, between-pen R(0) (0.58 (0.23-1.47)) was always significantly lower than within-pen R(0). Only beta(within) was sensitive to the assumption on end of infectiousness and decreased with increasing duration of infectiousness. These results showed that PCV-2 transmission is influenced by contact structure that appears worth being taken into account in an epidemic model.

  4. A nine-base nucleotide sequence in the porcine circovirus type 2 (PCV2) nucleocapsid gene determines viral replication and virulence.

    PubMed

    Krakowka, Steven; Allan, Gordon; Ellis, John; Hamberg, Alexander; Charreyre, Catherine; Kaufmann, Eva; Brooks, Charles; Meehan, Brian

    2012-03-01

    Porcine circovirus type 2 (PCV2) was retrospectively identified by serology in swine populations as an asymptomatic infection at least 25 years prior to the first reported case of PCV2-associated postweaning multisystemic wasting syndrome (PMWS). To investigate the sudden emergence of PMWS, viral sequences were amplified from frozen archived (1970-1971) porcine tissues and the complete genome of archival PCV2 was determined. The ORF1 gene product (viral DNA replicase) was homologous to contemporary PCV2 ORF1. In ORF2 (viral nucleocapsid gene) archival PCV2, a consistent linear nine-base sequence difference at base positions 1331 through 1339 was observed. The deduced amino acid sequence from these base changes alters the nucleocapsid conformation within the second immunogenic epitope from a hydrophobic (contemporary PCV2) to a hydrophilic (archival PCV2) configuration. To test the hypothesis that archival PCV2 was avirulent, cloned engineered archival and contemporary PCV2 genomes were constructed wherein the ORF1 gene was identical in each clone and the ORF2 gene (nucleocapsid protein) was sequence-identical in both clones except for the nine-base difference (bases 1331-1339), corresponding to archival and contemporary PCV2 viruses respectively. Clones were transfected into porcine kidney (PK) 15 cells and, after sequence confirmation, further passed in PK15 and 3D4/2 porcine alveolar macrophage cell cultures. Virulence trials in gnotobiotic piglets were conducted with cloned PCV2s. The data show that archival PCV2 is avirulent when compared to contemporary PCV2 and supports the hypothesis that the emergence of virulent contemporary PCV2 was a result of mutational events within this critical epitope after 1971.

  5. VENTILATION NEEDS DURING CONSTRUCTION

    SciTech Connect

    C.R. Gorrell

    1998-07-23

    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.

  6. Modes of mechanical ventilation for the operating room.

    PubMed

    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

  7. Mixed treatment comparison meta-analysis of porcine circovirus type 2 (PCV2) vaccines used in piglets.

    PubMed

    da Silva, N; Carriquiry, A; O'Neill, K; Opriessnig, T; O'Connor, A M

    2014-12-01

    Porcine circovirus type 2 (PCV2) vaccination is globally one of the most commonly used intervention strategies in growing pigs since several products became commercially available in 2006. While multiple trials have described the efficacy of individual PCV2 vaccines relative to non-vaccination, few studies provide product-to-product comparisons of efficacy. Given the well-documented efficacy of PCV2 vaccines, information about the comparative efficacy of available vaccines is more relevant to producers and veterinarians than comparison to non-vaccination. The objective of this study was to provide comparative estimates of changes in average daily gain effect associated with the use of the commercially available PCV2 vaccines. PubMed, CAB Abstracts, AGRICOLA, the USA Department of Agriculture Center for Veterinary Biologics database of licenses and provisions, and the proceedings of the Annual Meeting of the American Association of Swine Veterinarians, the Allen D. Leman Swine Conference, the Iowa State University Swine Disease Conference for Swine Practitioners, and the International Pig Veterinary Society Congress were used as the sources of information. Trials of licensed PCV2 vaccines administered according to manufacturers' specifications to intensively raised piglets with a known herd porcine reproductive and respiratory syndrome virus (PRRSV) status were considered relevant to the meta-analysis. Relevant studies had to report average daily gain (ADG) from weaning to finish and PCV2 infection had to be naturally occurring.

  8. Distribution of ORF2 and ORF3 genotypes of porcine circovirus type 2 (PCV-2) in wild boars and domestic pigs in Germany.

    PubMed

    Reiner, Gerald; Bronnert, Bastian; Hohloch, Corinna; Reinacher, Manfred; Willems, Hermann

    2011-03-24

    Porcine circovirus 2 (PCV-2), the essential infectious agent in PCVD (porcine circovirus diseases) circulates at high rates among domestic pig and wild boar populations. Wild boars may be viremic and shed the virus with excretions and secretions, and thus serve as a reservoir for domestic pig PCV-2 infection. We hypothesize that PCV-2 strains circulating in wild boars and in domestic pigs are significantly different and thus, partially independent. To prove this hypothesis, the present study investigated by sequence analysis the distribution of ORF2 and ORF3 genotypes of the PCV-2 genome within wild boars (n=40) and domestic pigs (n=60) from overlapping greater areas of Germany. The genotypes were compared with PCV-2 sequences from the Genbank database. The dominating genotype in domestic pigs was PCV-2b (98.4% of infected pigs), while only 4.8% of them were infected with PCV-2a. The corresponding prevalences of PCV-2a and -2b genotypes in wild boars were 58% and 70%, respectively. When also ORF3 genotypes were taken into account, more than 50% of wild boar PCV-2 genotypes were rare among German and European domestic pigs. In conclusion, these data provide evidence for a certain independence of PCV-2 infections in both species and a low chance for domestic pigs to be infected with PCV-2 of wild boar origin. On the other hand, PCV-2 genotypes specific for domestic pigs are also common in wild boars, although at lower frequencies, suggesting the spread of domestic pig PCV-2 to the wild boar population.

  9. Tank Pressure Control Experiment/thermal Phenomena (TPCE/TP)

    NASA Technical Reports Server (NTRS)

    Hasan, M. M.; Knoll, R. H.

    1992-01-01

    The 'Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP)' is a reflight of the tank pressure control experiment (TPCE), flown on STS-43 in a standard Get-Away Special (GAS) container in August 1991. The TPCE obtained extensive video and digital data of the jet induced mixing process in a partially filled tank in low gravity environments. It also provided limited data on the thermal processes involved. The primary objective of the reflight of TPCE is to investigate experimentally the phenomena of liquid superheating and pool nucleate boiling at very low heat fluxes in a long duration low gravity environment. The findings of this experiment will be of direct relevance to space based subcritical cryogenic fluid system design and operation. Experiment hardware and results from the first TPCE are described in outline and graphic form.

  10. Evaluating the impact of PCV-10 on invasive pneumococcal disease in Brazil: A time-series analysis

    PubMed Central

    Andrade, Ana Lucia; Minamisava, Ruth; Policena, Gabriela; Cristo, Elier B; Domingues, Carla Magda S; de Cunto Brandileone, Maria Cristina; Almeida, Samanta Cristine Grassi; Toscano, Cristiana Maria; Bierrenbach, Ana Luiza

    2016-01-01

    Routine infant immunization with 10-valent pneumococcal conjugate vaccine (PCV-10) began in Brazil in 2010. The impact of the PCV-10 on rates of invasive pneumococcal disease (IPD) at the population level was not yet evaluated. Serotype-specific IPD changes after PCV-10 introduction is still to be determined. Data from national surveillance system for notifiable diseases (SINAN) and national reference laboratory for S. pneumoniae in Brazil (IAL) were linked to enhance case ascertainment of IPD. An interrupted time-series analysis was conducted to predict trends in the postvaccination IPD rates in the absence of PCV-10 vaccination, taking into consideration seasonality and secular trends. PCVs serotype-specific distribution were assessed before (2008–2009) and after (2011–2013) the introduction of PCV-10 in the immunization program. A total of 9,827 IPD cases were identified from 2008–2013 when combining SINAN and IAL databases. Overall, PCV-10 types decreased by 41.3% after PCV-10 vaccination period, mostly in children aged 2–23 months, while additional PCV-13 serotypes increased by 62.8% mainly in children under 5-year of age. For children aged 2–23 months, targeted by the immunization program, we observed a 44.2% (95%CI, 15.8–72.5%) reduction in IPD rates. In contrast, significant increase in IPD rates were observed for adults aged 18–39 y (18.9%, 95%CI 1.1–36.7%), 40–64 y (52.5%, 95%CI 24.8–80.3%), and elderly ≥ 65 y (79.3%, 95%CI 62.1–96.5%). This is the first report of a time-series analysis for PCV impact in IPD conducted at national level data in a developing country. We were able to show significant impact of PCV-10 on IPD for age groups targeted by vaccination in Brazil, 3 y after its introduction. No impact on other age groups was demonstrated. PMID:26905679

  11. Evaluating the impact of PCV-10 on invasive pneumococcal disease in Brazil: A time-series analysis.

    PubMed

    Andrade, Ana Lucia; Minamisava, Ruth; Policena, Gabriela; Cristo, Elier B; Domingues, Carla Magda S; de Cunto Brandileone, Maria Cristina; Almeida, Samanta Cristine Grassi; Toscano, Cristiana Maria; Bierrenbach, Ana Luiza

    2016-01-01

    Routine infant immunization with 10-valent pneumococcal conjugate vaccine (PCV-10) began in Brazil in 2010. The impact of the PCV-10 on rates of invasive pneumococcal disease (IPD) at the population level was not yet evaluated. Serotype-specific IPD changes after PCV-10 introduction is still to be determined. Data from national surveillance system for notifiable diseases (SINAN) and national reference laboratory for S. pneumoniae in Brazil (IAL) were linked to enhance case ascertainment of IPD. An interrupted time-series analysis was conducted to predict trends in the postvaccination IPD rates in the absence of PCV-10 vaccination, taking into consideration seasonality and secular trends. PCVs serotype-specific distribution were assessed before (2008-2009) and after (2011-2013) the introduction of PCV-10 in the immunization program. A total of 9,827 IPD cases were identified from 2008-2013 when combining SINAN and IAL databases. Overall, PCV-10 types decreased by 41.3% after PCV-10 vaccination period, mostly in children aged 2-23 months, while additional PCV-13 serotypes increased by 62.8% mainly in children under 5-year of age. For children aged 2-23 months, targeted by the immunization program, we observed a 44.2% (95%CI, 15.8-72.5%) reduction in IPD rates. In contrast, significant increase in IPD rates were observed for adults aged 18-39 y (18.9%, 95%CI 1.1-36.7%), 40-64 y (52.5%, 95%CI 24.8-80.3%), and elderly ≥ 65 y (79.3%, 95%CI 62.1-96.5%). This is the first report of a time-series analysis for PCV impact in IPD conducted at national level data in a developing country. We were able to show significant impact of PCV-10 on IPD for age groups targeted by vaccination in Brazil, 3 y after its introduction. No impact on other age groups was demonstrated.

  12. Cryogenic Pressure Control Modeling for Ellipsoidal Space Tanks

    NASA Technical Reports Server (NTRS)

    Lopez, Alfredo; Grayson, Gary D.; Chandler, Frank O.; Hastings, Leon J.; Heyadat, Ali

    2007-01-01

    A computational fluid dynamics (CFD) model is developed to simulate pressure control of an ellipsoidal-shaped liquid hydrogen tank under external heating in normal gravity. Pressure control is provided by an axial jet thermodynamic vent system (TVS) centered within the vessel that injects cooler liquid into the tank, mixing the contents and reducing tank pressure. The two-phase cryogenic tank model considers liquid hydrogen in its own vapor with liquid density varying with temperature only and a fully compressible ullage. The axisymmetric model is developed using a custom version of the commercially available FLOW-31) software. Quantitative model validation is ,provided by engineering checkout tests performed at Marshall Space Flight Center in 1999 in support of the Solar Thermal Upper Stage_ Technology Demonstrator (STUSTD) program. The engineering checkout tests provide cryogenic tank self-pressurization test data at various heat leaks and tank fill levels. The predicted self-pressurization rates, ullage and liquid temperatures at discrete locations within the STUSTD tank are in good agreement with test data. The work presented here advances current CFD modeling capabilities for cryogenic pressure control and helps develop a low cost CFD-based design process for space hardware.

  13. Effect of porcine circovirus type 2 (PCV2) load in serum on average daily weight gain during the postweaning period.

    PubMed

    López-Soria, S; Sibila, M; Nofrarías, M; Calsamiglia, M; Manzanilla, E G; Ramírez-Mendoza, H; Mínguez, A; Serrano, J M; Marín, O; Joisel, F; Charreyre, C; Segalés, J

    2014-12-05

    Porcine circovirus type 2 (PCV2) is a ubiquitous virus that mainly affects nursery and fattening pigs causing systemic disease (PCV2-SD) or subclinical infection. A characteristic sign in both presentations is reduction of average daily weight gain (ADWG). The present study aimed to assess the relationship between PCV2 load in serum and ADWG from 3 (weaning) to 21 weeks of age (slaughter) (ADWG 3-21). Thus, three different boar lines were used to inseminate sows from two PCV2-SD affected farms. One or two pigs per sow were selected (60, 61 and 51 piglets from Pietrain, Pietrain×Large White and Duroc×Large White boar lines, respectively). Pigs were bled at 3, 9, 15 and 21 weeks of age and weighted at 3 and 21 weeks. Area under the curve of the viral load at all sampling times (AUCqPCR 3-21) was calculated for each animal according to standard and real time quantitative PCR results; this variable was categorized as "negative or low" (<10(4.3) PCV2 genome copies/ml of serum), "medium" (≥10(4.3) to ≤10(5.3)) and "high" (>10(5.3)). Data regarding sex, PCV2 antibody titre at weaning and sow parity was also collected. A generalized linear model was performed, obtaining that paternal genetic line and AUCqPCR 3-21 were related to ADWG 3-21. ADWG 3-21 (mean±typical error) for "negative or low", "medium" and "high" AUCqPCR 3-21 was 672±9, 650±12 and 603±16 g/day, respectively, showing significant differences among them. This study describes different ADWG performances in 3 pig populations that suffered from different degrees of PCV2 viraemia.

  14. Impact of protein binding cavity volume (PCV) and ligand volume (LV) in rigid and flexible docking of protein-ligand complexes.

    PubMed

    Saranya, N; Jeyakanthan, J; Selvaraj, S

    2012-12-15

    The importance of protein binding cavity volume (PCV) and ligand volume (LV) in rigid and flexible docking has been studied in 48 protein-ligand complexes belonging to eight protein families. In continuation of our earlier study on protein flexibility in relationship to PCV and LV, this study analyzes the importance of PCV and LV in the scoring and ranking of ligands in docking experiments. Crystal structures of protein-ligand complexes with varied PCV were chosen for docking ligands of varied volume in each protein family. Docking and scoring accuracy have been evaluated by self and cross docking of ligands to the given protein conformation. Effect of PCV and LV in rigid and flexible docking has been studied both in apo and holo proteins. Rigid docking has performed well when appropriate protein conformation is used. Selecting the proteins with appropriate PCV based on the LV information is suggested for better results in ensemble docking.

  15. Neurally adjusted ventilator assist in very low birth weight infants: Current status

    PubMed Central

    Narchi, Hassib; Chedid, Fares

    2015-01-01

    Continuous improvements in perinatal care have resulted in increased survival of premature infants. Their immature lungs are prone to injury with mechanical ventilation and this may develop into chronic lung disease (CLD) or bronchopulmonary dysplasia. Strategies to minimize the risk of lung injury have been developed and include improved antenatal management (education, regionalization, steroids, and antibiotics), exogenous surfactant administration and reduction of barotrauma by using exclusive or early noninvasive ventilatory support. The most frequently used mode of assisted ventilation is pressure support ventilation that may lead to patient-ventilator asynchrony that is associated with poor outcome. Ventilator-induced diaphragmatic dysfunction or disuse atrophy of diaphragm fibers may also occur. This has led to the development of new ventilation modes including neurally adjusted ventilatory assist (NAVA). This ventilation mode is controlled by electrodes embedded within a nasogastric catheter which detect the electrical diaphragmatic activity (Edi) and transmit it to trigger the ventilator in synchrony with the patient’s own respiratory efforts. This permits the patient to control peak inspiratory pressure, mean airway pressure and tidal volume. Back up pressure control (PC) is provided when there is no Edi signal and no pneumatic trigger. Compared with standard conventional ventilation, NAVA improves blood gas regulation with lower peak inspiratory pressure and oxygen requirements in preterm infants. NAVA is safe mode of ventilation. The majority of studies have shown no significant adverse events in neonates ventilated with NAVA nor a difference in the rate of intraventricular hemorrhage, pneumothorax, or necrotizing enterocolitis when compared to conventional ventilation. Future large size randomized controlled trials should be established to compare NAVA with volume targeted and pressure controlled ventilation in newborns with mature respiratory drive

  16. VENTILATION MODEL REPORT

    SciTech Connect

    V. Chipman

    2002-10-31

    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.

  17. Determination of Characteristics of Erythromycin Resistant Streptococcus pneumoniae with Preferred PCV Usage in Iran.

    PubMed

    Talebi, Malihe; Azadegan, Azadeh; Sadeghi, Javad; Ahmadi, Ali; Ghanei, Mostafa; Katouli, Mohammad; Owlia, Parviz; Pourshafie, Mohammad R

    2016-01-01

    Amongst 100 Streptococcus pneumoniae isolated from clinical cases and nasopharynx of healthy individuals, 60 erythromycin resistant strains were isolated and characterized using MLST, PFGE, transposon analysis and Quellung reaction. Most of the S. pneumoniae erythromycin resistant (80%) were found to be attributable to the ermB-edncoded ribosome methylase activity which differs from the dominant mechanism of macrolide resistance seen in North America. The most predominant transposons were; Tn1545/6003 (27%), Tn6002 (22%), Tn2009 (20%), Tn2010 (17%). Number of the clinical isolates carrying Tn2010 was more significant than the normal flora. The serotypes found were; 14 (33%), 3 (22%), 23F (15%), 19F (15%), 19A (7%), 6A (3%), 9V (3%) and 6B (2%). The most prevalent serotypes among the clinical (n = 28) and normal flora (n = 32) isolates were serotypes 14 (46%) and 3 (31%), respectively. The most prevalent vaccine serotypes amongst the clinical isolates and the healthy individuals were pneumococcal conjugate vaccines (PCV) 13 and PCV10, respectively. PFGE revealed 34 pulsotypes with 9 common and 25 single types. Significant number of the normal isolates belonged to CT5 and CT6. On the other hand, significant number of clinical isolates belonged to CT8 as compared to the normal flora isolates. MLST showed 2 dominant sequence types. ST3130 (23%) and ST180 (22%) were the most predominant sequence types in the clinical and normal isolates, respectively. There was no significant difference in other sequence types between clinical and normal flora isolates. Three polyclonal complexes including Sweden15A -25, Spain23F-1 and Spain9V-3 constituted 58% of the isolates. Our results suggest that the genetic diversity and transposon distribution were high among S. pneumoniae, particularly in the isolates containing erm(B) and double antibiotic resistant genes (erm/mef). The results presented here could influence the change in the current vaccination practices in Iran which

  18. Determination of Characteristics of Erythromycin Resistant Streptococcus pneumoniae with Preferred PCV Usage in Iran

    PubMed Central

    Talebi, Malihe; Azadegan, Azadeh; Sadeghi, Javad; Ahmadi, Ali; Katouli, Mohammad

    2016-01-01

    Amongst 100 Streptococcus pneumoniae isolated from clinical cases and nasopharynx of healthy individuals, 60 erythromycin resistant strains were isolated and characterized using MLST, PFGE, transposon analysis and Quellung reaction. Most of the S. pneumoniae erythromycin resistant (80%) were found to be attributable to the ermB-edncoded ribosome methylase activity which differs from the dominant mechanism of macrolide resistance seen in North America. The most predominant transposons were; Tn1545/6003 (27%), Tn6002 (22%), Tn2009 (20%), Tn2010 (17%). Number of the clinical isolates carrying Tn2010 was more significant than the normal flora. The serotypes found were; 14 (33%), 3 (22%), 23F (15%), 19F (15%), 19A (7%), 6A (3%), 9V (3%) and 6B (2%). The most prevalent serotypes among the clinical (n = 28) and normal flora (n = 32) isolates were serotypes 14 (46%) and 3 (31%), respectively. The most prevalent vaccine serotypes amongst the clinical isolates and the healthy individuals were pneumococcal conjugate vaccines (PCV) 13 and PCV10, respectively. PFGE revealed 34 pulsotypes with 9 common and 25 single types. Significant number of the normal isolates belonged to CT5 and CT6. On the other hand, significant number of clinical isolates belonged to CT8 as compared to the normal flora isolates. MLST showed 2 dominant sequence types. ST3130 (23%) and ST180 (22%) were the most predominant sequence types in the clinical and normal isolates, respectively. There was no significant difference in other sequence types between clinical and normal flora isolates. Three polyclonal complexes including Sweden15A -25, Spain23F-1 and Spain9V-3 constituted 58% of the isolates. Our results suggest that the genetic diversity and transposon distribution were high among S. pneumoniae, particularly in the isolates containing erm(B) and double antibiotic resistant genes (erm/mef). The results presented here could influence the change in the current vaccination practices in Iran which

  19. VENTILATION TECHNOLOGY SYSTEMS ANALYSIS

    EPA Science Inventory

    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 ...

  20. Over-expression of pcvA involved in vesicle-vacuolar fusion affects the conidiation and penicillin production in Penicillium chrysogenum.

    PubMed

    Xu, Xinxin; Yang, Jing; An, Yang; Pan, Yuanyuan; Liu, Gang

    2012-03-01

    Rab GTPase is required for vesicle-vacuolar fusion during the vacuolar biogenesis in fungi. Rab GTPase-encoding gene, pcvA, was cloned from Penicillium chrysogenum: it contained five introns and its predicted protein contained the conserved Rab GTPase domain involved in GTP-binding and hydrolysis. Over-expression of pcvA significantly stimulated the vesicle-vacuolar fusion but repressed the conidiation and decreased conidial tolerance against thermal stress. Penicillin production was decreased in the pcvA over-expressed strain suggesting that pcvA is involved in vesicle-vacuolar fusion participates in the penicillin biosynthesis in P. chrysogenum.

  1. Porcine circovirus type 2 (PCV2) evolution before and after the vaccination introduction: A large scale epidemiological study

    PubMed Central

    Franzo, Giovanni; Tucciarone, Claudia Maria; Cecchinato, Mattia; Drigo, Michele

    2016-01-01

    Since their commercialization, vaccines against Porcine circovirus type 2 (PCV2) have been the cornerstone control strategy. Nevertheless, the periodic emergence of new genotype waves and the recent reports of vaccine failure outbreaks have raised the question if widespread vaccination strategies could have driven viral evolution and affected different genotype fitness. To investigate this issue an in-deep analysis, based on a bioinformatics and biostatistics approach, has been implemented. ORF2 sequences from vaccinated and non-vaccinated populations (i.e. domestic pigs before and after vaccine introduction and wild boars) were considered. The action of selective forces on PCV2 strains has been analyzed and compared among groups. Remarkable differences were found in the selective forces acting on viral populations circulating in different “immune environments”. Particularly for PCV2a, a directional selection promoting a change in the viral capsid away from the vaccine specific antigenic determinants has been detected after vaccine introduction. Involved amino acids were previously reported to be part of viral epitopes whose variability is responsible of immune escape. Our findings support a change in PCV2 evolutionary pattern after widespread vaccination introduction and stress once more the compulsoriness of a continuous monitoring of PCV2 epidemiology to promptly act in response to the emergence of possible vaccine-escaping mutants. PMID:27991573

  2. Impact of two-way air flow due to temperature difference on preventing the entry of outdoor particles using indoor positive pressure control method.

    PubMed

    Chen, Chun; Zhao, Bin; Yang, Xudong

    2011-02-28

    Maintaining positive pressure indoors using mechanical ventilation system is a popular control method for preventing the entry of outdoor airborne particles. The idea is, as long as the supply air flow rate is larger than return air flow rate, the pressure inside the ventilated room should be positive since the superfluous air flow must exfiltrate from air leakages or other openings of the room to the outdoors. Based on experimental and theoretical analyses this paper aims to show the impact of two-way air flow due to indoor/outdoor temperature difference on preventing the entry of outdoor particles using positive pressure control method. The indoor positive pressure control method is effective only when the size of the opening area is restricted to a certain level, opening degree less than 30° in this study, due to the two-way air flow effect induced by differential temperature. The theoretical model was validated using the experimental data. The impacts of two-way air flow due to temperature difference and the supply air flow rate were also analyzed using the theoretical model as well as experimental data. For real houses, it seems that the idea about the positive pressure control method for preventing the entry of outdoor particles has a blind side.

  3. A noninvasive high frequency oscillation ventilator: Achieved by utilizing a blower and a valve

    NASA Astrophysics Data System (ADS)

    Yuan, YueYang; Sun, JianGuo; Wang, Baicun; Feng, Pei; Yang, ChongChang

    2016-02-01

    After the High Frequency Oscillatory Ventilation (HFOV) has been applied in the invasive ventilator, the new technique of noninvasive High Frequency Oscillatory Ventilation (nHFOV) which does not require opening the patient's airway has attracted much attention from the field. This paper proposes the design of an experimental positive pressure-controlled nHFOV ventilator which utilizes a blower and a special valve and has three ventilation modes: spontaneous controlled ventilation combining HFOV, time-cycled ventilation combining HFOV (T-HFOV), and continuous positive airway pressure ventilation combining HFOV. Experiments on respiratory model are conducted and demonstrated the feasibility of using nHFOV through the control of fan and valve. The experimental ventilator is able to produce an air flow with small tidal volume (VT) and a large minute ventilation volume (MV) using regular breath tubes and nasal mask (e.g., under T-HFOV mode, with a maximum tidal volume of 100 ml, the minute ventilation volume reached 14 400 ml). In the process of transmission, there is only a minor loss of oscillation pressure. (Under experimental condition and with an oscillation frequency of 2-10 Hz, peak pressure loss was around 0%-50% when it reaches the mask.)

  4. A noninvasive high frequency oscillation ventilator: Achieved by utilizing a blower and a valve.

    PubMed

    Yuan, YueYang; Sun, JianGuo; Wang, Baicun; Feng, Pei; Yang, ChongChang

    2016-02-01

    After the High Frequency Oscillatory Ventilation (HFOV) has been applied in the invasive ventilator, the new technique of noninvasive High Frequency Oscillatory Ventilation (nHFOV) which does not require opening the patient's airway has attracted much attention from the field. This paper proposes the design of an experimental positive pressure-controlled nHFOV ventilator which utilizes a blower and a special valve and has three ventilation modes: spontaneous controlled ventilation combining HFOV, time-cycled ventilation combining HFOV (T-HFOV), and continuous positive airway pressure ventilation combining HFOV. Experiments on respiratory model are conducted and demonstrated the feasibility of using nHFOV through the control of fan and valve. The experimental ventilator is able to produce an air flow with small tidal volume (VT) and a large minute ventilation volume (MV) using regular breath tubes and nasal mask (e.g., under T-HFOV mode, with a maximum tidal volume of 100 ml, the minute ventilation volume reached 14,400 ml). In the process of transmission, there is only a minor loss of oscillation pressure. (Under experimental condition and with an oscillation frequency of 2-10 Hz, peak pressure loss was around 0%-50% when it reaches the mask.).

  5. Tank Pressure Control Experiment on the Space Shuttle

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The tank pressure control experiment is a demonstration of NASA intent to develop new technology for low-gravity management of the cryogenic fluids that will be required for future space systems. The experiment will use freon as the test fluid to measure the effects of jet-induced fluid mixing on storage tank pressure and will produce data on low-gravity mixing processes critical to the design of on-orbit cryogenic storage and resupply systems. Basic data on fluid motion and thermodynamics in low gravity is limited, but such data is critical to the development of space transfer vehicles and spacecraft resupply facilities. An in-space experiment is needed to obtain reliable data on fluid mixing and pressure control because none of the available microgravity test facilities provide a low enough gravity level for a sufficient duration to duplicate in-space flow patterns and thermal processes. Normal gravity tests do not represent the fluid behavior properly; drop-tower tests are limited in length of time available; aircraft low-gravity tests cannot provide the steady near-zero gravity level and long duration needed to study the subtle processes expected in space.

  6. DEMAND CONTROLLED VENTILATION AND CLASSROOM VENTILATION

    SciTech Connect

    Fisk, William J.; Mendell, Mark J.; Davies, Molly; Eliseeva, Ekaterina; Faulkner, David; Hong, Tienzen; Sullivan, Douglas P.

    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. Major findings included: ? The single-location carbon dioxide sensors widely used for demand controlled ventilation frequently have large errors and will fail to effectively control ventilation rates (VRs).? Multi-location carbon dioxide measurement systems with more expensive sensors connected to multi-location sampling systems may measure carbon dioxide more accurately.? Currently-available optical people counting systems work well much of the time but have large counting errors in some situations. ? In meeting rooms, measurements of carbon dioxide at return-air grilles appear to be a better choice than wall-mounted sensors.? In California, demand controlled ventilation in general office spaces is projected to save significant energy and be cost effective only if typical VRs without demand controlled ventilation are very high relative to VRs in codes. Based on the research, several recommendations were developed for demand controlled ventilation specifications in the California Title 24 Building Energy Efficiency Standards.The research on classroom ventilation collected data over two years on California elementary school classrooms to investigate associations between VRs and student illness absence (IA). Major findings included: ? Median classroom VRs in all studied climate zones were below the California guideline, and 40percent lower in portable than permanent buildings.? Overall, one additional L/s per person of VR was associated with 1.6percent less IA. ? Increasing average VRs in California K-12 classrooms from the current average to the required level is estimated to decrease IA by 3.4percent, increasing State attendance-based funding to school districts by $33M, with $6.2 M in increased energy costs. Further VR increases would provide additional benefits

  7. CN-18RELATIONSHIPS BETWEEN DOSE INTENSITY, TOXICITY, AND OUTCOME IN OLIGODENDROGLIAL TUMORS (OG) TREATED WITH PCV REGIMEN

    PubMed Central

    Tabouret, Emeline; Reyes-Botero, German; Dehais, Caroline; Daros, Marine; Barrie, Maryline; Matta, Mona; Petrirena, Gregorio; Autran, Didier; Duran, Alberto; Boucard, Celine; Delattre, Jean Yves; Chinot, Olivier

    2014-01-01

    BACKGROUND: In grade II and codeleted grade III gliomas, the procarbazine-CCNU-vincristine (PCV) combination increase survival when added to radiotherapy as first line treatment, despite the important toxicity of this treatment schedule. Our objective was to analyze the tolerance, feasibility and impact of dose intensity of the PCV regimen on outcome for patients with OG. METHODS: We retrospectively reviewed all grade III OG patients receiving PCV (CCNU:110mg/m2) who were referred to our two institutions. The total dose and dose adaptation, cycle delay, dose intensity, toxicity and premature discontinuation of CCNU were analyzed. Impact of these factors on patient outcome was evaluated. RESULTS: Between 2007 and 2011, 89 patients received PCV. Only 37% completed 6 cycles, whereas 13.4% prematurely discontinued PCV because of toxicity. Cycle delay and dose reduction were observed for 62% and 70% patients, respectively. Grade 3 and 4 toxicities were observed in 38% and 8% patients, respectively. Among patients who did not progress under PCV regimen, by multivariate analysis, premature discontinuation for toxicity was significantly correlated with poor PFS (p = 0.023, Hazard ratio (HR):2.354) and OS (p = 0.021, HR:5.093). By univariate analyses, absence of CCNU dose adaptation was correlated to poor PFS (p = 0.032). For OS, pejorative factors were high total CCNU dose (p = 0.029), absence of cycle delay (p = 0.009), absence of CCNU dose adaptation (p = 0.020) and grade 3/4 toxicities (p = 0.013). High CCNU dose-intensity tended to poorly impact PFS (p = 0.053) and OS (p = 0.112). By multivariate analysis, absence of CCNU dose adaptation remained significant for PFS (p = 0.001), while OS was negatively impacted by the absence of cycle delay (p = 0.049) and grade 3/4 toxicities (p = 0.045). CONCLUSION: Despite the efficacy of the PCV regimen, significant toxicity is associated with this schedule, which appears to impact its feasibility and efficacy. The optimal PCV

  8. Ventilation Model Report

    SciTech Connect

    V. Chipman; J. Case

    2002-12-20

    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 post-closure analyses. The Ventilation Model report was initially developed to analyze the effects of preclosure continuous ventilation in the Engineered Barrier System (EBS) emplacement drifts, and to provide heat removal data to support EBS design. Revision 00 of the Ventilation Model included documentation of the modeling results from the ANSYS-based heat transfer model. Revision 01 ICN 01 included the results of the unqualified software code MULTIFLUX to assess the influence of moisture on the ventilation efficiency. The purposes of Revision 02 of the Ventilation Model are: (1) To validate the conceptual model for preclosure ventilation of emplacement drifts and verify its numerical application in accordance with new procedural requirements as outlined in AP-SIII-10Q, Models (Section 7.0). (2) To satisfy technical issues posed in KTI agreement RDTME 3.14 (Reamer and Williams 2001a). Specifically to demonstrate, with respect to the ANSYS ventilation model, the adequacy of

  9. The comparison of manual and LabVIEW-based fuzzy control on mechanical ventilation.

    PubMed

    Guler, Hasan; Ata, Fikret

    2014-09-01

    The aim of this article is to develop a knowledge-based therapy for management of rats with respiratory distress. A mechanical ventilator was designed to achieve this aim. The designed ventilator is called an intelligent mechanical ventilator since fuzzy logic was used to control the pneumatic equipment according to the rat's status. LabVIEW software was used to control all equipments in the ventilator prototype and to monitor respiratory variables in the experiment. The designed ventilator can be controlled both manually and by fuzzy logic. Eight female Wistar-Albino rats were used to test the designed ventilator and to show the effectiveness of fuzzy control over manual control on pressure control ventilation mode. The anesthetized rats were first ventilated for 20 min manually. After that time, they were ventilated for 20 min by fuzzy logic. Student's t-test for p < 0.05 was applied to the measured minimum, maximum and mean peak inspiration pressures to analyze the obtained results. The results show that there is no statistical difference in the rat's lung parameters before and after the experiments. It can be said that the designed ventilator and developed knowledge-based therapy support artificial respiration of living things successfully.

  10. Protective garment ventilation system

    NASA Technical Reports Server (NTRS)

    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.

  11. Noninvasive ventilation in trauma

    PubMed Central

    Karcz, Marcin K; Papadakos, Peter J

    2015-01-01

    Trauma patients are a diverse population with heterogeneous needs for ventilatory support. This requirement depends mainly on the severity of their ventilatory dysfunction, degree of deterioration in gaseous exchange, any associated injuries, and the individual feasibility of potentially using a noninvasive ventilation approach. Noninvasive ventilation may reduce the need to intubate patients with trauma-related hypoxemia. It is well-known that these patients are at increased risk to develop hypoxemic respiratory failure which may or may not be associated with hypercapnia. Hypoxemia in these patients is due to ventilation perfusion mismatching and right to left shunt because of lung contusion, atelectasis, an inability to clear secretions as well as pneumothorax and/or hemothorax, all of which are common in trauma patients. Noninvasive ventilation has been tried in these patients in order to avoid the complications related to endotracheal intubation, mainly ventilator-associated pneumonia. The potential usefulness of noninvasive ventilation in the ventilatory management of trauma patients, though reported in various studies, has not been sufficiently investigated on a large scale. According to the British Thoracic Society guidelines, the indications and efficacy of noninvasive ventilation treatment in respiratory distress induced by trauma have thus far been inconsistent and merely received a low grade recommendation. In this review paper, we analyse and compare the results of various studies in which noninvasive ventilation was applied and discuss the role and efficacy of this ventilator modality in trauma. PMID:25685722

  12. DIFFERENCE IN SEVERITY OF PORCINE CIRCOVIRUS TYPE 2 (PCV2)-INDUCED PATHOLOGICAL LESIONS AND DISEASE BETWEEN LANDRACE AND PIETRAIN PIGS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anecdotal information from pig producers and veterinarians in the field suggests that there are genetic differences in susceptibility to porcine circovirus type 2 (PCV2) associated disease (PCVAD) among Landrace and Pietrain breeds. The objective of this study was to determine if a difference exist...

  13. Ventilatory failure, ventilator support, and ventilator weaning.

    PubMed

    Tobin, Martin J; Laghi, Franco; Jubran, Amal

    2012-10-01

    The development of acute ventilatory failure represents an inability of the respiratory control system to maintain a level of respiratory motor output to cope with the metabolic demands of the body. The level of respiratory motor output is also the main determinant of the degree of respiratory distress experienced by such patients. As ventilatory failure progresses and patient distress increases, mechanical ventilation is instituted to help the respiratory muscles cope with the heightened workload. While a patient is connected to a ventilator, a physician's ability to align the rhythm of the machine with the rhythm of the patient's respiratory centers becomes the primary determinant of the level of rest accorded to the respiratory muscles. Problems of alignment are manifested as failure to trigger, double triggering, an inflationary gas-flow that fails to match inspiratory demands, and an inflation phase that persists after a patient's respiratory centers have switched to expiration. With recovery from disorders that precipitated the initial bout of acute ventilatory failure, attempts are made to discontinue the ventilator (weaning). About 20% of weaning attempts fail, ultimately, because the respiratory controller is unable to sustain ventilation and this failure is signaled by development of rapid shallow breathing. Substantial advances in the medical management of acute ventilatory failure that requires ventilator assistance are most likely to result from research yielding novel insights into the operation of the respiratory control system.

  14. Solar Thermal Upper Stage Liquid Hydrogen Pressure Control Testing

    NASA Technical Reports Server (NTRS)

    Moore, J. D.; Otto, J. M.; Cody, J. C.; Hastings, L. J.; Bryant, C. B.; Gautney, T. T.

    2015-01-01

    High-energy cryogenic propellant is an essential element in future space exploration programs. Therefore, NASA and its industrial partners are committed to an advanced development/technology program that will broaden the experience base for the entire cryogenic fluid management community. Furthermore, the high cost of microgravity experiments has motivated NASA to establish government/aerospace industry teams to aggressively explore combinations of ground testing and analytical modeling to the greatest extent possible, thereby benefitting both industry and government entities. One such team consisting of ManTech SRS, Inc., Edwards Air Force Base, and Marshall Space Flight Center (MSFC) was formed to pursue a technology project designed to demonstrate technology readiness for an SRS liquid hydrogen (LH2) in-space propellant management concept. The subject testing was cooperatively performed June 21-30, 2000, through a partially reimbursable Space Act Agreement between SRS, MSFC, and the Air Force Research Laboratory. The joint statement of work used to guide the technical activity is presented in appendix A. The key elements of the SRS concept consisted of an LH2 storage and supply system that used all of the vented H2 for solar engine thrusting, accommodated pressure control without a thermodynamic vent system (TVS), and minimized or eliminated the need for a capillary liquid acquisition device (LAD). The strategy was to balance the LH2 storage tank pressure control requirements with the engine thrusting requirements to selectively provide either liquid or vapor H2 at a controlled rate to a solar thermal engine in the low-gravity environment of space operations. The overall test objective was to verify that the proposed concept could enable simultaneous control of LH2 tank pressure and feed system flow to the thruster without necessitating a TVS and a capillary LAD. The primary program objectives were designed to demonstrate technology readiness of the SRS concept

  15. Tank Pressure Control Experiment: Thermal Phenomena in Microgravity

    NASA Technical Reports Server (NTRS)

    Hasan, Mohammad M.; Lin, Chin S.; Knoll, Richard H.; Bentz, Michael D.

    1996-01-01

    The report presents the results of the flight experiment Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP) performed in the microgravity environment of the space shuttle. TPCE/TP, flown on the Space Transportation System STS-52, was a second flight of the Tank Pressure Control Experiment (TPCE). The experiment used Freon 113 at near saturation conditions. The test tank was filled with liquid to about 83% by volume. The experiment consisted of 21 tests. Each test generally started with a heating phase to increase the tank pressure and to develop temperature stratification in the fluid, followed by a fluid mixing phase for the tank pressure reduction and fluid temperature equilibration. The heating phase provided pool boiling data from large (relative to bubble sizes) heating surfaces (0.1046 m by 0.0742 m) at low heat fluxes (0.23 to 1.16 kW/sq m). The system pressure and the bulk liquid subcooling varied from 39 to 78 kPa and 1 to 3 C, respectively. The boiling process during the entire heating period, as well as the jet-induced mixing process for the first 2 min of the mixing period, was also recorded on video. The unique features of the experimental results are the sustainability of high liquid superheats for long periods and the occurrence of explosive boiling at low heat fluxes (0.86 to 1.1 kW/sq m). For a heat flux of 0.97 kW/sq m, a wall superheat of 17.9 C was attained in 10 min of heating. This superheat was followed by an explosive boiling accompanied by a pressure spike of about 38% of the tank pressure at the inception of boiling. However, at this heat flux the vapor blanketing the heating surface could not be sustained. Steady nucleate boiling continued after the explosive boiling. The jet-induced fluid mixing results were obtained for jet Reynolds numbers of 1900 to 8000 and Weber numbers of 0.2 to 6.5. Analyses of data from the two flight experiments (TPCE and TPCE/TP) and their comparison with the results obtained in drop tower experiments

  16. Guide to Home Ventilation

    SciTech Connect

    2010-10-01

    A fact sheet from the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy: Ventilation refers to the exchange of indoor and outdoor air. Without proper ventilation, an otherwise insulated and airtight house will seal in harmful pollutants, such as carbon monoxide, and moisture that can damage a house.

  17. Multifamily Ventilation Retrofit Strategies

    SciTech Connect

    Ueno, K.; Lstiburek, J.; Bergey, D.

    2012-12-01

    In multifamily buildings, central ventilation systems often have poor performance, overventilating some portions of the building (causing excess energy use), while simultaneously underventilating other portions (causing diminished indoor air quality). BSC and Innova Services Corporation performed a series of field tests at a mid-rise test building undergoing a major energy audit and retrofit, which included ventilation system upgrades.

  18. Tank pressure control in low gravity by jet mixing

    NASA Technical Reports Server (NTRS)

    Bentz, Michael D.

    1993-01-01

    The Tank Pressure Control Experiment (TPCE) is a space experiment developed to help meet the need for a critical aspect of cryogenic fluid management technology: control of storage tank pressures in the absence of gravity by forced convective mixing. The experiment used a 13.7-liter tank filled to a constant 83 percent level with refrigerant 113 at near saturation conditions to simulate the fluid dynamics and thermodynamics of cryogenic fluids in space applications. The objectives of TPCE were to characterize the fluid dynamics of axial jet-induced mixing in low gravity, to evaluate the validity of empirical mixing models, and to provide data for use in developing and validating computational fluid dynamic models of mixing processes. TPCE accomplished all of its objectives in flight on Space Shuttle Mission STS-3 in August of 1991. The range of flow patterns photographed generally confirmed a prior correlation based on drop tower tests. A closed-form equation derived from a simple thermodynamic model was found to provide a first-order prediction of the pressure reduction time as a function of mixer parameters, tank size, and fluid thermophysical properties. Low energy mixing jets were found to be effective and reliable at reducing thermal non-uniformities, promoting heat and mass transfer between the phases, and reducing tank pressure.

  19. [New concepts for pressure-controlled glaucoma implants].

    PubMed

    Allemann, R; Stachs, O; Falke, K; Schmidt, W; Siewert, S; Sternberg, K; Chichkov, B; Wree, A; Schmitz, K-P; Guthoff, R F

    2013-08-01

    In industrialized countries glaucoma is one of the most common causes that leads to blindness. It is also the most common cause of irreversible blindness worldwide. In addition to local treatment of intraocular pressure and filtering glaucoma surgery, alloplastic implants are increasingly being used in glaucoma therapy. As long-term results published in the literature of commonly used implants are unsatisfactory, it seems useful to search for new concepts. In order to avoid the well-known short-term and long-term postoperative complications a pressure-controlled microstent with antiproliferative surface modifications was developed. Additionally, the functionality of such a microstent should be investigated using an animal glaucoma model. This paper describes the concept of a microstent which drains aquous humour from the anterior chamber into the suprachoroidal space. In addition, the glaucoma models described in the literature are discussed. Unfortunately, none of the methods could be reproduced permanently. First results show a correct implantation of a coated microstent with valve where the anti-proliferative effect could be demonstrated histologically. The promising results should lead to further investigations and the final goal will be the testing of the stent in the human eye.

  20. [Blood pressure control in the area of surgical interventions].

    PubMed

    Simanski, Olaf; Janda, Matthias; Bajorat, Jörn; Nguyen, Ngon C; Hofmockel, Rainer; Lampe, Bernhard P

    2009-10-01

    For specific surgical interventions, such as aortic stent implantation, it might be temporarily necessary to decrease mean arterial pressure to rather low levels (around 40 mm Hg). Such hypotensive pressure levels are necessary to avoid intra- and postoperative intricacies. Traditionally, the drug Nitroprussidnatrium is used for this task. To adjust the correct amount of drug to reach the target pressure as fast as possible and without overshoot, the anaesthetists typically use empirical knowledge and might need several minutes until the target point is reached. In our research group, an adaptive control system was developed for this task which is able to compute and set the transient drug release automatically. For the design and testing of the adaptive control strategy, the well known Guyton model was implemented into the MATLAB/Simulink development environment. This paper describes the implementation and adaption of the Guyton model to hypotensive pressure control and provides some algorithmic details of the adaptive control strategy for automatic drug delivery in deep hypotension. The designed control system was successfully validated in animal trials (25 trials on 7 pigs). Following this, an additional controller component for increase of blood pressure with the help of the drug Noradrenalin was implemented. It is now possible to increase blood pressure to a specific value to save defined cerebral perfusion pressure for patients with craniocerebral injury. In a second pilot trial, this controller extension was tested in 10 pigs.

  1. Subcellular immunolocalization of porcine circovirus type 2 (PCV2) in lymph nodes from pigs with post-weaning multisystemic wasting syndrome (PMWS).

    PubMed

    Rodríguez-Cariño, C; Sánchez-Chardi, A; Segalés, J

    2010-05-01

    Post-weaning multisystemic wasting syndrome (PMWS) is one of the most significant porcine diseases worldwide. The causative agent is porcine circovirus type 2 (PCV2), the smallest virus known to infect animals. Data related to the structural and ultrastructural aspects of this infectious disease are sparse and there is little knowledge of the subcellular localization of PCV2 and its replication in the tissues of pigs naturally affected by PMWS. The present study describes the cellular localization of PCV2 in the lymph nodes of pigs affected by PMWS by application of immunolabelling techniques for light and transmission electron microscopy (TEM). PCV2 particles were exclusively detected in histiocytes. Ultrastructural alterations including marked dilatation of rough endoplasmic reticulum and swelling of mitochondria were associated with PCV2-labelled intracytoplasmic inclusions (ICIs) with recognizable virions. Within the ICIs icosahedral virus-like particles were specifically labelled with a PCV2 capsid antibody, whereas particles with a granular appearance were not labelled. Colocalization studies with confocal microscopy and double immunolabelling with TEM indicated a close relationship between virus and the mitochondria, suggesting that these organelles may play an important role in the replication of PCV2. The present findings further support the hypothesis that virus replicates within the histiocytes of lymph nodes.

  2. Construction of a novel porcine circovirus type 2 infectious clone as a basis for the development of a PCV2 iDNA vaccine.

    PubMed

    Wang, Wei-Cheng; Zeng, Zhi-Yong; Tang, De-Yuan; Liang, Hai-Ying; Liu, Zhao; Dai, Zhen-Jiang

    2015-08-01

    Porcine circovirus-associated disease is a highly contagious disease that has significant economic consequences. The disease is prevalent in many countries and regions. To generate a genetic marker strain of PCV2, a Sal I restriction enzyme site was inserted into the PCV2 clone as a genetic marker by applying iDNA infectious clone technology. The iDNA represents plasmids that encode the full-length DNA genome of PCV2 assembled in a pcDNA3.1-based vectors. The mutant PCV2 was rescued by transfecting an infectious clone into PK-15 cells and was characterised by an immunoperoxidase monolayer assay (IPMA). The viral genome could be differentiated from the wild-type parent by PCR and restriction fragment length polymorphism (PCR-RFLP). Kunming mice were inoculated with the PCV2 infectious clone or rescued virus via intranasal and intraperitoneal routes. Seroconversion to PCV2-specific antibody appeared in the majority of mice from the two inoculated groups at 7 days postinoculation (DPI), and the specific antibody level was steady for at least 42 days. Viraemia, beginning at 7 DPI and lasting 4 weeks, was detected in the majority of the pigs from the two inoculated groups. The animal experiments revealed that the PCV2 infectious clone and rescued virus both could replicate in mice and induce mice to generate anti-PCV2 antibodies. The infectious clones of PCV2 will be useful for further research investigating a potential tractable iDNA vaccine by reverse genetics technology for attenuated virulance.

  3. A Pressure Control Method for Emulsion Pump Station Based on Elman Neural Network

    PubMed Central

    Tan, Chao; Qi, Nan; Yao, Xingang; Wang, Zhongbin; Si, Lei

    2015-01-01

    In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others. PMID:25861253

  4. A pressure control method for emulsion pump station based on Elman neural network.

    PubMed

    Tan, Chao; Qi, Nan; Zhou, Xin; Liu, Xinhua; Yao, Xingang; Wang, Zhongbin; Si, Lei

    2015-01-01

    In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others.

  5. Ventilating Air-Conditioner

    NASA Technical Reports Server (NTRS)

    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.

  6. Vaccination with a Porcine Reproductive and Respiratory Syndrome (PRRS) Modified Live Virus Vaccine Followed by Challenge with PRRS Virus and Porcine Circovirus Type 2 (PCV2) Protects against PRRS but Enhances PCV2 Replication and Pathogenesis Compared to Results for Nonvaccinated Cochallenged Controls

    PubMed Central

    Bawa, Bhupinder; Serão, Nick V. L.; Trible, Benjamin R.; Kerrigan, Maureen A.; Lunney, Joan K.; Dekkers, Jack C. M.; Rowland, Raymond R. R.

    2015-01-01

    Coinfections involving porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) contribute to a group of disease syndromes known as porcine circovirus-associated disease (PCVAD). Presumably, PRRSV infection enhances PCV2 replication as a result of modulation of host immunity. The purpose of this study was to evaluate PCV2 replication and pathogenesis in pigs vaccinated with a PRRS modified live virus (MLV) vaccine and subsequently challenged with a combination of PRRSV and PCV2. During the early postchallenge period, the number of pigs with PRRSV-associated clinical signs was decreased, and average daily gain (ADG) was increased, in the vaccinated group, demonstrating the protective effect of PRRS vaccination. However, during the later postchallenge period, more pigs in the vaccinated group showed increased PCV2 viremia, decreased ADG, increased PCVAD clinical signs, and increased mortality. In this disease model, the early benefits of PRRSV vaccination were outweighed by the later amplification of PCVAD. PMID:26446422

  7. Pressure Control System Design for a Closed Crop Growth Chamber

    NASA Technical Reports Server (NTRS)

    Tsai, K.; Blackwell, C.; Harper, Lynn D. (Technical Monitor)

    1994-01-01

    The Controlled Ecological Life Support System (CELSS) is an area of active research at NASA. CELSS is a plant-based bioregenerative life support system for long term manned space flights where resupply is costly or impractical. The plants in a CELSS will function to convert the carbon dioxide (exhaled by the crew) into oxygen, purify non-potable water into potable quality water, and provide food for the crew. Prior to implementing a CELSS life support system, one must have knowledge on growing plants in a closed chamber under low gravity. This information will come from research to be conducted on the CELSS Test Facility that will operate on the Space Station Freedom. Currently a ground-based CELSS Test Facility is being built at NASA Ames Research Center. It is called the EDU (Engineering Development Unit). This system will allow researchers to identify issues that may cause difficulties in the development of the CELSS Test Facility and aid in the development of new needed technologies. The EDU consists of a 1 m2 crop growth chamber that is surrounded by a containment enclosure. The containment enclosure isolates the system so there is very little mass and thermal exchange with the ambient. The leakage rate is on the order of 1 % of the enclosure's volume per day (with 0.2S psi pressure difference). The thermal leakage is less than 0.5% of the electrical power supplied to the system per degree Celsius difference from the surrounding. The pressure in the containment enclosure is regulated at 62.5 Pa below the ambient by an active controller. The goal is to maintain this set point for a variety of conditions, such as a range of operating temperatures, heat load variations that occur when the lights are turned on and off, and fluctuations in ambient pressure. In addition certain transition tracking performance is required. This paper illustrates the application of some advanced systems control methods to the task of synthesizing the EDU's pressure control system.

  8. Why We Ventilate

    SciTech Connect

    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.

  9. Conventional mechanical ventilation

    PubMed Central

    Tobias, Joseph D.

    2010-01-01

    The provision of mechanical ventilation for the support of infants and children with respiratory failure or insufficiency is one of the most common techniques that are performed in the Pediatric Intensive Care Unit (PICU). Despite its widespread application in the PICUs of the 21st century, before the 1930s, respiratory failure was uniformly fatal due to the lack of equipment and techniques for airway management and ventilatory support. The operating rooms of the 1950s and 1960s provided the arena for the development of the manual skills and the refinement of the equipment needed for airway management, which subsequently led to the more widespread use of endotracheal intubation thereby ushering in the era of positive pressure ventilation. Although there seems to be an ever increasing complexity in the techniques of mechanical ventilation, its successful use in the PICU should be guided by the basic principles of gas exchange and the physiology of respiratory function. With an understanding of these key concepts and the use of basic concepts of mechanical ventilation, this technique can be successfully applied in both the PICU and the operating room. This article reviews the basic physiology of gas exchange, principles of pulmonary physiology, and the concepts of mechanical ventilation to provide an overview of the knowledge required for the provision of conventional mechanical ventilation in various clinical arenas. PMID:20927268

  10. Serologic response to porcine circovirus type 1 (PCV1) in infants vaccinated with the human rotavirus vaccine, Rotarix™: A retrospective laboratory analysis

    PubMed Central

    Han, Htay Htay; Karkada, Naveen; Jayadeva, Girish; Dubin, Gary

    2017-01-01

    ABSTRACT In 2010, porcine circovirus type 1 (PCV1) material was unexpectedly detected in the oral live-attenuated human rotavirus (RV) vaccine, Rotarix™ (GSK Vaccines, Belgium). An initial study (NCT01511133) found no immunologic response against PCV1 in 40 vaccinated infants. As a follow-up, the current study (NCT02153333), searched for evidence of post-vaccination serologic response to PCV1 in a larger number of archived serum samples. Unlike the previous study, serum anti-PCV1 antibodies were assessed with an adapted Immuno Peroxidase Monolayer Assay (IPMA) using a Vero-adapted PCV1 strain. Samples from 596 infants who participated in clinical trials of the human RV vaccine were randomly selected and analyzed. The observed anti-PCV1 antibody seropositivity rate 1–2 months post-dose 2 was approximately 1% [90% Confidence Interval (CI): 0.3–2.6] (3/299 samples) in infants who received the human RV vaccine and 0.3% [90% CI: 0.0–1.6] (1/297 samples) in those who received placebo; the difference between the groups was −0.66 [90% CI: −2.16–0.60]. One subject in the vaccinated group was also seropositive before vaccination. Notably, the seropositivity rate observed in vaccinated subjects was below that observed during assay qualification in samples from unvaccinated subjects outside of this study (2.5%; 5/200 samples). No serious adverse events had been reported in any of the 4 subjects providing anti-PCV1 positive samples during the 31-day post-vaccination follow-up period in the original studies. In conclusion, the presence of PCV1 in the human RV vaccine is considered to be a manufacturing quality issue and does not appear to pose a safety risk to vaccinated infants. PMID:27657348

  11. 14 CFR 25.831 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.831 Ventilation... probable failures or malfunctioning of the ventilating, heating, pressurization, or other systems...

  12. 14 CFR 25.831 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.831 Ventilation... probable failures or malfunctioning of the ventilating, heating, pressurization, or other systems...

  13. 14 CFR 25.831 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.831 Ventilation... probable failures or malfunctioning of the ventilating, heating, pressurization, or other systems...

  14. 14 CFR 25.831 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.831 Ventilation... probable failures or malfunctioning of the ventilating, heating, pressurization, or other systems...

  15. 14 CFR 25.831 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.831 Ventilation... probable failures or malfunctioning of the ventilating, heating, pressurization, or other systems...

  16. NINTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    SciTech Connect

    Daugherty, W.

    2014-08-06

    A series of experiments to monitor the aging performance of Viton® GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. One approach has been to periodically evaluate the leak performance of O-rings being aged in mock-up 9975 Primary Containment Vessels (PCVs) at elevated temperatures. Other methods such as compression-stress relaxation (CSR) tests and field surveillance are also on-going to evaluate O-ring behavior. Seventy tests using PCV mock-ups were assembled and heated to temperatures ranging from 200 to 450 ºF. They were leak-tested initially and have been tested periodically to determine if they continue to meet the leak-tightness criterion defined in ANSI standard N14.5-97. Due to material substitution, fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 ºF. High temperature aging continues for 23 GLT O-ring fixtures at 200 – 270 ºF. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 ºF and higher temperatures, and in 8 fixtures aging at 300 ºF. The earliest 300 °F GLT O-ring fixture failure was observed at 34 months. The remaining GLT O-ring fixtures aging at 300 ºF have been retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 ºF for 72 - 96 months, which bounds O-ring temperatures anticipated during storage in K-Area Complex (KAC). Based on expectations that the 200 ºF fixtures will remain leak-tight for a significant period yet to come, 2 additional fixtures began aging in 2011 at 270 ºF, with hopes that they may reach a failure condition before the 200 ºF fixtures, thus providing additional time to failure data. High temperature aging continues for 6 GLT-S O-ring fixtures at 200 – 300 ºF. Room temperature leak test failures have been experienced in all 8 of the

  17. Ventilation technologies scoping study

    SciTech Connect

    Walker, Iain S.; Sherman, Max H.

    2003-09-30

    This document presents the findings of a scoping study commissioned by the Public Interest Energy Research (PIER) program of the California Energy Commission to determine what research is necessary to develop new residential ventilation requirements for California. This study is one of three companion efforts needed to complete the job of determining the needs of California, determining residential ventilation requirements, and determining appropriate ventilation technologies to meet these needs and requirements in an energy efficient manner. Rather than providing research results, this scoping study identifies important research questions along with the level of effort necessary to address these questions and the costs, risks, and benefits of pursuing alternative research questions. In approaching these questions and level of effort, feasibility and timing were important considerations. The Commission has specified Summer 2005 as the latest date for completing this research in time to update the 2008 version of California's Energy Code (Title 24).

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

    SciTech Connect

    Sherman, Max H.; Walker, Iain S.

    2011-04-01

    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 outdoor pollutant levels are high, the importance of minimizing energy use particularly during times of peak electricity demand, and how the energy used to condition air as part of ventilation system operation changes with outdoor conditions. Dynamic control of ventilation systems can provide ventilation equivalent to or better than what is required by standards while minimizing energy costs and can also add value by shifting load during peak times and reducing intake of outdoor air contaminants. This article describes the logic that enables dynamic control of whole-house ventilation systems to meet the intent of ventilation standards and demonstrates the dynamic ventilation system control concept through simulations and field tests of the Residential Integrated Ventilation-Energy Controller (RIVEC).

  19. Ventilation flow: Submerged

    NASA Technical Reports Server (NTRS)

    Hutchinson, D.

    1985-01-01

    The ventilation system on a submarine is discussed. When the submarine is submerged. The ventilation system provides a conditioned atmosphere in the ship with complete isolation from the outside. A conditioned atmosphere includes not only filtration and temperature and humidity control, but also air purification (removal of potentially harmful quantities of impurities and comtaminants) and revitalization (addition of vital life support oxygen). Carbon dioxide removal, the oxygen system, air conditioning, carbon monoxide removal, hydrogen removal, and atmosphere monitoring systems are among the topics discussed.

  20. Pulmonary ventilation/perfusion scan

    MedlinePlus

    ... JavaScript. A pulmonary ventilation/perfusion scan involves two nuclear scan tests to measure breathing (ventilation) and circulation ( ... In: Mettler FA, Guiberteau MJ, eds. Essentials of Nuclear Medicine Imaging . 6th ed. Philadelphia, PA: Elsevier Saunders; ...

  1. Central Fan Integrated Ventilation Systems

    SciTech Connect

    2009-05-12

    This information sheet describes one example of a ventilation system design, a central fan integrated supply (CFIS) system, a mechanical ventilation and pollutant source control to ensure that there is reasonable indoor air quality inside the house.

  2. Nursing Education in High Blood Pressure Control. Report of the Task Force on the Role of Nursing in High Blood Pressure Control.

    ERIC Educational Resources Information Center

    National Institutes of Health (DHEW), Bethesda, MD. High Blood Pressure Information Center.

    This curriculum guide on high blood pressure (hypertension) for nursing educators has five sections: (1) Introduction and Objectives provides information regarding the establishment and objectives of the National Task Force on the Role of Nursing in High Blood Pressure Control and briefly discusses nursing's role in hypertension control; (2) Goals…

  3. How to Plan Ventilation Systems.

    ERIC Educational Resources Information Center

    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…

  4. EIGHTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    SciTech Connect

    Daugherty, W. L.

    2013-09-03

    A series of experiments to monitor the aging performance of Viton® GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. Seventy tests using mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 ºF. They were leak-tested initially and have been tested periodically to determine if they meet the criterion of leak-tightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 ºF. High temperature aging continues for 23 GLT O-ring fixtures at 200 – 270 ºF. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 ºF and higher temperatures, and in 8 fixtures aging at 300 ºF. The remaining GLT O-ring fixtures aging at 300 ºF have been retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 ºF for 61 - 85 months, which is still bounding to O-ring temperatures during storage in KArea Complex (KAC). Based on expectations that the fixtures aging at 200 ºF will remain leaktight for a significant period yet to come, 2 additional fixtures began aging in 2011 at an intermediate temperature of 270 ºF, with hopes that they may reach a failure condition before the 200 ºF fixtures. High temperature aging continues for 6 GLT-S O-ring fixtures at 200 – 300 ºF. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 ºF. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 - 300 ºF for 41 - 45 months. Aging and periodic leak testing will continue for the remaining PCV fixtures.

  5. Consistent Blood Pressure Control May Cut Rate of Second Stroke in Half

    MedlinePlus

    ... News on Heart.org Learn More Consistent blood pressure control may cut rate of second stroke in ... heart.org and strokeassociation.org Related Images Blood Pressure Check (2) Checking blood pressure using cuff copyright ...

  6. Nasopharyngeal Carriage of Streptococcus pneumoniae among Children in an Urban Setting in Brazil prior to PCV10 Introduction

    PubMed Central

    Menezes, Ana Paula de O.; Azevedo, Jailton; Leite, Mariela C.; Campos, Leila C.; Cunha, Marcelo; Carvalho, Maria da Gloria S.; Reis, Mitermayer G.; Ko, Albert I.; Weinberger, Daniel M.; Ribeiro, Guilherme; Reis, Joice N.

    2015-01-01

    Information on pneumococcal carriage in the pre-vaccine period is essential to predict and assess the impact of PCV in settings where disease surveillance is particularly difficult. Therefore, we present data on pneumococcal carriage before the introduction of the 10-valent-pneumococcal conjugate vaccine (PCV10) in Brazil. We conducted a prospective study on a cohort of 203 children aged < 5 years-old, randomly selected in an urban community located in the periphery of the city of Salvador, Brazil and followed them from January/2008 to January/2009. Nasopharyngeal swabs were collected from each child at four times. In total, 721 swabs were collected, yielding a pneumococcal carriage prevalence of 55% (n=398). In multivariate analyses, the variables associated with carriage were having contact with three or more children <2 years old (OR, 2.00; 95% CI 1.33–2.89) and living in a house with an average of 3 residents per room (OR, 1.77; 95% CI 1.05–3.10). Also, white participants were more likely to be protected from colonization (OR, 0.52; 95% CI 0.29–0.93), and prevalence of carriage varied over time, with lower prevalence occurring from February to June (OR, 0.53; 95% CI 0.37–0.78) compared to July to January. Contact with children under two years of age and living in crowded housing also were associated with colonization by highly invasive serotypes, although this relationship was not significant. The most prevalent vaccine serotypes were 6A/B (25.4%), 19F (10.1%) and 14 (9.0%), while the most prevalent non-vaccine serotypes were 16F (4.8%), 15B/C (4.5%) and 6C/D (3.5%). Overall, 38.4% (153/398) of the isolates were non-susceptible to penicillin, and of those, 73.8% (113/153) were non-susceptible to trimethoprim/sulfamethoxazole. Colonization rate by PCV10 serotypes was 52.2%. Routine PCV10 vaccination can lead to significant changes in pneumococcal serotypes found in NP colonization, indicating a need for continued monitoring, especially in crowded

  7. A nationwide surveillance of invasive pneumococcal disease in adults in Israel before an expected effect of PCV7.

    PubMed

    Regev-Yochay, Gili; Rahav, Galia; Strahilevitz, Jacob; Bishara, Jihad; Katzir, Michal; Chowers, Michal; Finkelstein, Renato; Chazan, Bibiana; Zimhony, Oren; Dagan, Ron

    2013-05-01

    Pneumococcal infections in adults vary in severity and incidence is affected by childhood vaccination policy. Here, we try to define the host determinants and the interaction with specific serotypes that result in invasive pneumococcal disease (IPD) before an expected effect of pneumococcal conjugate vaccines. A nationwide active surveillance was initiated on July 2009, at the time of national implementation of PCV7 in Israel. The surveillance included all 27 laboratories and medical centers performing blood cultures in Israel, providing all blood and CSF pneumococcal isolates from persons ≥18y. Capture-recapture method assured that >95% of all cases were reported. IPD outcome and medical history were recorded and isolates were serotyped. Four hundred and sixty IPD cases were reported (annual incidence [/100,000] of 9.25). Incidence increased with age, from 2.6 among 18-34y to 66.8 among ≥85y. The most common diagnosis was pneumonia (72.4%), followed by bacteremia with no apparent focus (20.2%). Case fatality rate increased with age and number of comorbidities (34.5% for ≥75y or those with ≥3 comorbidities vs. 9.2-11.2% among <65y or those with no comorbidities; p=0.015). Variables independently associated with mortality were: age ≥75, chronic renal failure, malignancy, neurosurgery, alcohol abuse, multi-lobar pneumonia and sepsis with no apparent focus. The predominant serotypes in patients 18-49y were 1, 5, 8, 7F and 9V (constituting 56.3% in this age-group vs. 11.9% in ≥75y; p<0.01). The predominant serotypes among patients ≥75y were 3, 19A, 23F and 14 (40.3% of this age-group vs. 12.9% of 18-49y; p<0.01). Overall, PCV7 and PCV13 covered 25.6% and 63.7% of isolates, respectively, and 30.9% and 67.9% of isolates in mortality cases respectively. This nationwide active surveillance provides the baseline incidence, mortality rates and risk group distributions of IPD in adults before expected PCV effect.

  8. Evaluation of self-perception of mechanical ventilation knowledge among Brazilian final-year medical students, residents and emergency physicians

    PubMed Central

    Tallo, Fernando Sabia; de Campos Vieira Abib, Simone; de Andrade Negri, Alexandre Jorgi; Filho, Paulo Cesar; Lopes, Renato Delascio; Lopes, Antônio Carlos

    2017-01-01

    OBJECTIVE: To present self-assessments of knowledge about mechanical ventilation made by final-year medical students, residents, and physicians taking qualifying courses at the Brazilian Society of Internal Medicine who work in urgent and emergency settings. METHODS: A 34-item questionnaire comprising different areas of knowledge and training in mechanical ventilation was given to 806 medical students, residents, and participants in qualifying courses at 11 medical schools in Brazil. The questionnaire’s self-assessment items for knowledge were transformed into scores. RESULTS: The average score among all participants was 21% (0-100%). Of the total, 85% respondents felt they did not receive sufficient information about mechanical ventilation during medical training. Additionally, 77% of the group reported that they would not know when to start noninvasive ventilation in a patient, and 81%, 81%, and 89% would not know how to start volume control, pressure control and pressure support ventilation modes, respectively. Furthermore, 86.4% and 94% of the participants believed they would not identify the basic principles of mechanical ventilation in patients with obstructive pulmonary disease and acute respiratory distress syndrome, respectively, and would feel insecure beginning ventilation. Finally, 77% said they would fear for the safety of a patient requiring invasive mechanical ventilation under their care. CONCLUSION: Self-assessment of knowledge and self-perception of safety for managing mechanical ventilation were deficient among residents, students and emergency physicians from a sample in Brazil. PMID:28273238

  9. Measure Guideline: Ventilation Cooling

    SciTech Connect

    Springer, D.; Dakin, B.; German, A.

    2012-04-01

    The purpose of this measure guideline on ventilation cooling is to provide information on a cost-effective solution for reducing cooling system energy and demand in homes located in hot-dry and cold-dry climates. This guideline provides a prescriptive approach that outlines qualification criteria, selection considerations, and design and installation procedures.

  10. Non-invasive ventilation.

    PubMed Central

    Spence, D.

    1996-01-01

    Nasal intermittent positive pressure ventilation is an effective treatment for nocturnal hypoventilation secondary to chest wall deformity or respiratory muscle weakness. Physicians should be aware that, in these groups of patients, disabling breathlessness can be alleviated and established cor pulmonale reversed by the technique. Images Figure 1 Figure 2 Figure 3 PMID:8949588

  11. Laboratory Ventilation and Safety.

    ERIC Educational Resources Information Center

    Steere, Norman V.

    1965-01-01

    In order to meet the needs of both safety and economy, laboratory ventilation systems must effectively remove air-borne toxic and flammable materials and at the same time exhaust a minimum volume of air. Laboratory hoods are the most commonly used means of removing gases, dusts, mists, vapors, and fumed from laboratory operations. To be effective,…

  12. Energy recovery ventilator

    SciTech Connect

    Schneider, S. L.; Dravnieks, K.

    1985-04-30

    An energy recovery ventilator adapted to be mounted on a roof and adapted to be connected to the outlet of an exhaust air duct of a building ventilation system and the inlet of an air supply duct of a building ventilation system. The energy recovery ventilator includes a housing having an exhaust air chamber and a supply air chamber separated by a divider wall. A circular heat transfer wheel is position in the housing, a portion of the wheel being housed in the exhaust air chamber and a second portion of the wheel being housed in the supply air chamber, and the heat transfer wheel is caused to rotate about a central axis. An exhaust fan is housed in the exhaust air chamber and causes exhaust air to be pulled through the exhaust air duct and the heat transfer wheel and to be exhausted from the housing. A supply air fan is housed in the supply air housing above the heat transfer wheel, and causes outside air to be drawn into the supply air chamber and to be forced through the heat transfer wheel into the air supply duct.

  13. Understanding mechanical ventilators.

    PubMed

    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.

  14. Space station ventilation study

    NASA Technical Reports Server (NTRS)

    Colombo, G. V.; Allen, G. E.

    1972-01-01

    A ventilation system design and selection method which is applicable to any manned vehicle were developed. The method was used to generate design options for the NASA 33-foot diameter space station, all of which meet the ventilation system design requirements. System characteristics such as weight, volume, and power were normalized to dollar costs for each option. Total system costs for the various options ranged from a worst case $8 million to a group of four which were all approximately $2 million. A system design was then chosen from the $2 million group and is presented in detail. A ventilation system layout was designed for the MSFC space station mockup which provided comfortable, efficient ventilation of the mockup. A conditioned air distribution system design for the 14-foot diameter modular space station, using the same techniques, is also presented. The tradeoff study resulted in the selection of a system which costs $1.9 million, as compared to the alternate configuration which would have cost $2.6 million.

  15. Patient-ventilator dyssynchrony during assisted invasive mechanical ventilation.

    PubMed

    Murias, G; Villagra, A; Blanch, L

    2013-04-01

    Patient-ventilator dyssynchrony is common during mechanical ventilation. Dyssynchrony decreases comfort, prolongs mechanical ventilation and intensive care unit stays, and might lead to worse outcome. Dyssynchrony can occur during the triggering of the ventilator, the inspiration period after triggering, the transition from inspiration to expiration, and the expiratory phase. The most common dyssynchronies are delayed triggering, autotriggering, ineffective inspiratory efforts (which can occur at any point in the respiratory cycle), mismatch between the patient's and ventilator's inspiratory times, and double triggering. At present, the detection of dyssynchronies usually depends on healthcare staff observing ventilator waveforms; however, performance is suboptimal and many events go undetected. To date, technological complexity has made it impossible to evaluate patient-ventilator synchrony throughout the course of mechanical ventilation. Studies have shown that a high index of dyssynchrony may increase the duration of mechanical ventilation. Better training, better ventilatory modes, and/or computerized systems that permit better synchronization of patients' demands and ventilator outputs are necessary to improve patient-ventilator synchrony.

  16. Cultivation of PCV2 in swine testicle cells using the shell vial technique and monitoring of viral replication by qPCR and RT-qPCR.

    PubMed

    Cruz, Taís F; Araujo, João P

    2014-02-01

    Porcine circovirus type 2 (PCV2) is difficult to isolate. Currently, no published articles have used the shell vial technique to isolate PCV2. In addition, the action of d-glucosamine on swine testicle cells (ST) has not been evaluated properly. Thus, the aim of this study was to determine an optimal concentration of d-glucosamine and to test the shell vial technique for PCV2 propagation in ST cells. The optimal concentration of d-glucosamine was determined to be 100mM. Because PCV2 is noncytopathic, the traditional adsorption was compared to the shell vial technique for 15 passages by qPCR, and RT-qPCR for passages 12 through 15. The quantities of viral DNA (P=0.013) and ORF1-mRNA detected with the shell vial technique were two-fold higher than the obtained with traditional adsorption. The levels of ORF2-mRNA were similar for both methods; however, by passage 15, a six-fold increase in levels was observed with the shell vial technique. Therefore, the shell vial technique was more efficient for the cultivation of PCV2, and qPCR/RT-qPCR can be used to monitor viral replication. In addition, a high viral load (>2.7×10(10) DNA copies/ml) and high levels of viral mRNA expression indicated that the ST cells were persistently infected.

  17. ASHRAE and residential ventilation

    SciTech Connect

    Sherman, Max H.

    2003-10-01

    In the last quarter of a century, the western world has become increasingly aware of environmental threats to health and safety. During this period, people psychologically retreated away from outdoors hazards such as pesticides, smog, lead, oil spills, and dioxin to the seeming security of their homes. However, the indoor environment may not be healthier than the outdoor environment, as has become more apparent over the past few years with issues such as mold, formaldehyde, and sick-building syndrome. While the built human environment has changed substantially over the past 10,000 years, human biology has not; poor indoor air quality creates health risks and can be uncomfortable. The human race has found, over time, that it is essential to manage the indoor environments of their homes. ASHRAE has long been in the business of ventilation, but most of the focus of that effort has been in the area of commercial and institutional buildings. Residential ventilation was traditionally not a major concern because it was felt that, between operable windows and envelope leakage, people were getting enough outside air in their homes. In the quarter of a century since the first oil shock, houses have gotten much more energy efficient. At the same time, the kinds of materials and functions in houses changed in character in response to people's needs. People became more environmentally conscious and aware not only about the resources they were consuming but about the environment in which they lived. All of these factors contributed to an increasing level of public concern about residential indoor air quality and ventilation. Where once there was an easy feeling about the residential indoor environment, there is now a desire to define levels of acceptability and performance. Many institutions--both public and private--have interests in Indoor Air Quality (IAQ), but ASHRAE, as the professional society that has had ventilation as part of its mission for over 100 years, is the

  18. Strict blood pressure control associates with decreased mortality risk by APOL1 genotype.

    PubMed

    Ku, Elaine; Lipkowitz, Michael S; Appel, Lawrence J; Parsa, Afshin; Gassman, Jennifer; Glidden, David V; Smogorzewski, Miroslaw; Hsu, Chi-Yuan

    2017-02-01

    Although APOL1 high-risk genotype partially accounts for the increased susceptibility of blacks to chronic kidney disease (CKD), whether APOL1 associates differentially with mortality risk remains controversial. Here we evaluate the association between APOL1 genotype and risk of death and determine whether APOL1 status modifies the association between strict versus usual blood pressure control and mortality risk. We performed a retrospective analysis of the African American Study of Kidney Disease and Hypertension trial that randomized black participants with CKD to strict versus usual blood pressure control from 1995 to 2001. This included 682 participants with known APOL1 genotype (157 with high-risk genotype) previously assigned to either strict (mean arterial pressure [MAP] 92 mm Hg or less) versus usual blood pressure control (MAP 102-107 mm Hg) during the trial. During a median follow-up of 14.5 years, risk of death did not differ between individuals with high- versus low-risk APOL1 genotypes (unadjusted hazard ratio 1.00 [95% confidence interval 0.76-1.33]). However, a significant interaction was detected between the APOL1 risk group and blood pressure control strategy. In the APOL1 high-risk group, the risk of death was 42% lower comparing strict versus usual blood pressure control (0.58 [0.35-0.97]). In the APOL1 low-risk group, the risk of death comparing strict versus usual blood pressure control was not significantly different (1.09 [0.84-1.43]). Thus, strict blood pressure control during CKD associates with a lower risk of death in blacks with the high-risk CKD APOL1 genotype. Knowledge of APOL1 status could inform selection of blood pressure treatment targets in black CKD patients.

  19. SEVENTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    SciTech Connect

    Daugherty, W.

    2012-08-30

    surveillance (24% average). For GLT O-rings, separate service life estimates have been made based on the O-ring fixture leak test data and based on compression stress relaxation (CSR) data. These two predictive models show reasonable agreement at higher temperatures (350 – 400 ºF). However, at 300 ºF, the room temperature leak test failures to date experienced longer aging times than predicted by the CSRbased model. This suggests that extrapolations of the CSR model predictions to temperatures below 300 ºF will provide a conservative prediction of service life relative to the leak rate criterion. Leak test failure data at lower temperatures are needed to verify this apparent trend. Insufficient failure data exist currently to perform a similar comparison for GLT-S O-rings. Aging and periodic leak testing will continue for the remaining PCV O-ring fixtures.

  20. Production of inflammatory cytokines in response to diphtheria-pertussis-tetanus (DPT), haemophilus influenzae type b (Hib), and 7-valent pneumococcal (PCV7) vaccines

    PubMed Central

    Kashiwagi, Yasuyo; Miyata, Akiko; Kumagai, Takuji; Maehara, Kouji; Suzuki, Eitarou; Nagai, Takao; Ozaki, Takao; Nishimura, Naoko; Okada, Kenji; Kawashima, Hisashi; Nakayama, Tetsuo

    2014-01-01

    Haemophilus influenzae type b (Hib) and 7-valent pneumococcal (PCV7) vaccines both became recommended in Japan in 2010. In this study, cytokine production was investigated in peripheral blood mononuclear cells (PBMCs) cultures stimulated with diphtheria and tetanus toxoids combined with acellular pertussis vaccine (DPT), Hib, and PCV7 separately or concurrent different combinations, all as final off-the-shelf vaccines without the individual vaccine components as controls. Higher IL-1β levels were produced when cultures were stimulated with PCV than with DPT or Hib, and the concurrent stimulation including PCV7 enhanced the production of IL-1β. Although Hib induced higher levels of IL-6, no significant difference was observed in IL-6 production with the concurrent stimulation. The concurrent stimulation with Hib/PCV7 and DPT/Hib/PCV7 produced higher levels of TNF-α and human G-CSF. Cytokine profiles were examined in serum samples obtained from 61 vaccine recipients with febrile reactions and 18 recipients without febrile illness within 24 h of vaccination. No significant difference was observed in cytokine levels of IL-1β, IL-4, IL-6, IL-10, IL-12, IFN-γ, MIP-1, TNF-α, and prostaglandin E2 (PGE2) in sera between the two groups. However, significantly higher levels of human G-CSF were observed in recipients with febrile illness than in those without febrile reactions. Further investigations of the significance of elevated serum G-CSF levels are required in vaccine recipients with febrile illness. PMID:24589970

  1. Ventilator-associated pneumonia.

    PubMed

    2009-11-01

    Ventilator-associated pneumonia is a pneumonia that develops initially more than 48 h from the start of tracheal intubation and mechanical ventilation. The route of infection is almost always through the respiratory tract. Intake of contaminants from outside the tracheal tube (silent aspiration) is considered a key route, and suctioning of secretions that have accumulated above the cuff of the endotracheal tubes is effective in preventing infection. The circuit is managed and heated-wire humidifiers and suction are manipulated based on appropriate infection control measures. To diagnose pathogens, efforts should be made to collect specimens from the pneumonia focus. Realistically, however, diagnosis can also be achieved based on the clinical course and from the results of culture of samples from tracheal aspirate. Use of prophylactic antimicrobials is not recommended, but once a diagnosis is made, antimicrobials are administered that combat the causative microorganism.

  2. Home Mechanical Ventilation in Children.

    PubMed

    Preutthipan, Aroonwan

    2015-09-01

    The number of children dependent on home mechanical ventilation has been reported to be increasing in many countries around the world. Home mechanical ventilation has been well accepted as a standard treatment of children with chronic respiratory failure. Some children may need mechanical ventilation as a lifelong therapy. To send mechanically ventilated children back home may be more difficult than adults. However, relatively better outcomes have been demonstrated in children. Children could be safely ventilated at home if they are selected and managed properly. Conditions requiring home ventilation include increased respiratory load from airway or lung pathologies, ventilatory muscle weakness and failure of neurologic control of ventilation. Home mechanical ventilation should be considered when the patient develops progressive respiratory failure or intractable failure to wean mechanical ventilation. Polysomnography or overnight pulse oximetry plus capnometry are used to detect nocturnal hypoventilation in early stage of respiratory failure. Ventilator strategy including non-invasive and invasive approach should be individualized for each patient. The author strongly believes that parents and family members are able to take care of their child at home if they are trained and educated effectively. A good team work with dedicated members is the key factor of success.

  3. Ventilators for noninvasive ventilation to treat acute respiratory failure.

    PubMed

    Scala, Raffaele; Naldi, Mario

    2008-08-01

    The application of noninvasive ventilation (NIV) to treat acute respiratory failure has increased tremendously both inside and outside the intensive care unit. The choice of ventilator is crucial for success of NIV in the acute setting, because poor tolerance and excessive air leaks are significantly correlated with NIV failure. Patient-ventilator asynchrony and discomfort can occur if the physician or respiratory therapist fails to adequately set NIV to respond to the patient's ventilatory demand, so clinicians need to fully understood the ventilator's technical peculiarities (eg, efficiency of trigger and cycle systems, speed of pressurization, air-leak compensation, CO(2) rebreathing, reliability of fraction of inspired oxygen reading, monitoring accuracy). A wide range of ventilators of different complexity have been introduced into clinical practice to noninvasively support patients in acute respiratory failure, but the numerous commercially available ventilators (bi-level, intermediate, and intensive care unit ventilators) have substantial differences that can influence patient comfort, patient-ventilator interaction, and, thus, the chance of NIV clinical success. This report examines the most relevant aspects of the historical evolution, the equipment, and the acute-respiratory-failure clinical application of NIV ventilators.

  4. 46 CFR 111.105-21 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Ventilation. 111.105-21 Section 111.105-21 Shipping... REQUIREMENTS Hazardous Locations § 111.105-21 Ventilation. A ventilation duct which ventilates a hazardous location has the classification of that location. Each fan for ventilation of a hazardous location must...

  5. 46 CFR 111.105-21 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Ventilation. 111.105-21 Section 111.105-21 Shipping... REQUIREMENTS Hazardous Locations § 111.105-21 Ventilation. A ventilation duct which ventilates a hazardous location has the classification of that location. Each fan for ventilation of a hazardous location must...

  6. 46 CFR 111.105-21 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Ventilation. 111.105-21 Section 111.105-21 Shipping... REQUIREMENTS Hazardous Locations § 111.105-21 Ventilation. A ventilation duct which ventilates a hazardous location has the classification of that location. Each fan for ventilation of a hazardous location must...

  7. Vaccination with a porcine reproductive and respiratory syndrome modified live virus vaccine followed by challenge with PRRSV and porcine circovirus type 2 protects against PRRS but enhances PCV2 replication and parthogenesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Co-infections involving porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) contribute to a group of disease syndromes known as porcine circovirus-associated disease (PCVAD). Presumably, PRRSV infection enhances PCV2 replication as a result of modulation...

  8. Serotype Distribution and Antimicrobial Sensitivity Profile of Streptococcus pneumoniae Carried in Healthy Toddlers before PCV13 Introduction in Niamey, Niger

    PubMed Central

    Sanda, Abdel-Kader A.; Soussou, Amadou M.

    2017-01-01

    Background To mitigate the burden of pneumococcal infections in Niger, a 13-valent pneumococcal vaccine, PCV13, was introduced for routine child vaccination in July 2014. In order to provide pre-vaccine baseline data and allow appreciation of changes on carriage due to vaccination, we analyzed retrospectively pneumococcal isolates obtained from healthy, 0 to 2 year old children prior to the vaccine introduction. Methods From June 5, 2007, to May 26, 2008, 1200 nasopharyngeal swabs were collected from healthy 0 to 2 year old children and analyzed by standard microbiological methods. Serotyping was done by SM-PCR and the data were analyzed with R version 2.15.0 (2012-03-30). Results Streptococcus pneumoniae was detected in 654/1200 children (54.5%) among whom 339 (51.8%) were males. The ages of the study subjects varied from few days to 26 months (mean = 7.1, median = 6, 95% CI [6.8–7.4]). Out of 654 frozen isolates, 377 (54.8%) were able to be re-grown and analyzed. In total, 32 different serogroups/serotypes were detected of which, the most prevalent were 6/(6A/6B/6C/6D) (15.6%), 23F (10.6%), 19F (9.3%), 14 (9%), 19A (5.6%), 23B (4.0%), 25F/38 (3.7%), 18/(18A/18B/18C/18F) (2.9%) and PCR non-typeable (16.4%). Eleven serogroups/serotypes accounting for 57.3% (216/377) were of PCV13 types. Of the 211/377 (56%) isolates tested for drug sensitivity, 23/211 (10.9%), 24/211 (11.4%), 9/211(4.3%) and 148/210 (70.5%) were respectively resistance to oxacillin, chloramphenicol, erythromycin and tetracycline. Thirteen of the oxacillin resistant isolates were additionally multidrug-resistant. No resistance was however detected to gentamycin500μg and to fluoroquinolones (ø Norfloxacin5μg <7mm). Age > 3 months and presence in family of more than one sibling aged < 6 years were significant risk factors for carriage. Conclusion A global rate of 54.5% pneumococcal carriage was detected in this study. The introduced PCV13 vaccine should cover 57.3% (216/377) of circulating

  9. Evaluation of newly installed SWEPOS mast stations, individual vs. type PCV antenna models and comparison with pillar stations

    NASA Astrophysics Data System (ADS)

    Nilfouroushan, Faramarz; Jivall, Lotti; Lilje, Christina; Steffen, Holger; Lidberg, Martin; Johansson, Jan; Jarlemark, Per

    2016-04-01

    For about two decades, SWEPOS (the Swedish Permanent GNSS network) pillar stations have been used in different geodetic and geodynamic studies. To keep continuous measurements of these long lived pillar stations and at the same time modernizing the SWEPOS network, it has been decided to install new truss mast stations, equipped with modern and individually calibrated antennas and radomes, capable of tracking all new GNSS satellites. Installation of mast stations started in 2011. Today, each pillar station in the SWEPOS permanent GNSS network has a close-by truss mast station, mostly in 10 meters distance with individual calibrated Leica choke ring antenna and its attachment (LEIAR25.R3, LEIT). Due to their closeness to pillars, the modern mast stations may provide additional information for the analysis of ground movements in Sweden e.g. to distinguish between tectonic and geodynamic processes (e.g. land uplift in Sweden). In this study, we have used two datasets from two different seasons for 21 pillars and 21 mast stations and formed different networks. The mast network has been processed using both IGS standard (type) and individually calibrated PCV (Phase Center Variation) models and therefore the effect of these two different PCV models on height components has been investigated. In a combined network, we processed all 42 stations (21 pillars+21 mast) to see how this multi-baseline network (861 baselines) combination differs from independent mast or pillar networks with much less baselines (210 baselines). For our analysis, we used the GAMIT-GLOBK software and compared different networks. Ambiguity resolutions, daily coordinate repeatability and differences between height components in different solutions are presented. Moreover, the GAMIT and BERNESE solutions for combined mast and pillar networks are compared. Our results suggest that the SWEPOS truss mast stations can reliably be used for crustal deformation studies. The comparison between pillar and mast

  10. Pulmonary mechanics during mechanical ventilation.

    PubMed

    Henderson, William R; Sheel, A William

    2012-03-15

    The use of mechanical ventilation has become widespread in the management of hypoxic respiratory failure. Investigations of pulmonary mechanics in this clinical scenario have demonstrated that there are significant differences in compliance, resistance and gas flow when compared with normal subjects. This paper will review the mechanisms by which pulmonary mechanics are assessed in mechanically ventilated patients and will review how the data can be used for investigative research purposes as well as to inform rational ventilator management.

  11. Simulation and experiment research on the proportional pressure control of water-assisted injection molding

    NASA Astrophysics Data System (ADS)

    Zhou, Hua; Chen, Yinglong; Zhang, Zengmeng; Yang, Huayong

    2012-05-01

    Water-assisted injection molding (WAIM), a newly developed fluid-assisted injection molding technology has drawn more and more attentions for the energy saving, short cooling circle time and high quality of products. Existing research for the process of WAIM has shown that the pressure control of the injecting water is mostly important for the WAIM. However, the proportional pressure control for the WAIM system is quite complex due to the existence of nonlinearities in the water hydraulic system. In order to achieve better pressure control performance of the injecting water to meet the requirements of the WAIM, the proportional pressure control of the WAIM system is investigated both numerically and experimentally. A newly designed water hydraulic system for WAIM is first modeled in AMEsim environment, the load characteristics and the nonlinearities of water hydraulic system are both considered, then the main factors affecting the injecting pressure and load flow rate are extensively studied. Meanwhile, an open-loop model-based compensation control strategy is employed to regulate the water injection pressure and a feedback proportional integrator controller is further adopted to achieve better control performance. In order to verify the AMEsim simulation results WAIM experiment for particular Acrylonitrile Butadiene Styrene (ABS) parts is implemented and the measured experimental data including injecting pressure and flow rate results are compared with the simulation. The good coincidence between experiment and simulation shows that the AMEsim model is accurate, and the tracking performance of the load pressure indicates that the proposed control strategy is effective for the proportional pressure control of the nonlinear WAIM system. The proposed proportional pressure control strategy and the conclusions drawn from simulation and experiment contribute to the application of water hydraulic proportional control and WAIM technology.

  12. Field measurement of ventilation rates.

    PubMed

    Persily, A K

    2016-02-01

    Ventilation rates have significant impacts on building energy use and indoor contaminant concentrations, making them key parameters in building performance. Ventilation rates have been measured in buildings for many decades, and there are mature measurement approaches available to researchers and others who need to know actual ventilation rates in buildings. Despite the fact that ventilation rates are critical in interpreting indoor concentration measurements, it is disconcerting how few Indoor Air Quality field studies measure ventilation rates or otherwise characterize the ventilation design of the study building(s). This paper summarizes parameters of interest in characterizing building ventilation, available methods for quantifying these parameters, and challenges in applying these methods to different types of buildings and ventilation systems. These parameters include whole-building air change rates, system outdoor air intake rates, and building infiltration rates. Tracer gas methods are reviewed as well as system airflow rate measurements using, for example, duct traverses. Several field studies of ventilation rates conducted over the past 75 years are described to highlight the approaches employed and the findings obtained.

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

    SciTech Connect

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

    1985-11-01

    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.

  14. Laboratory and Industrial Ventilation

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This handbook supplements the Facilities Engineering Handbook (NHB 7320.1) and provides additional policies and criteria for uniform application to ventilation systems. It expands basic requirements, provides additional design and construction guidance, and places emphasis on those design considerations which will provide for greater effectiveness in the use of these systems. The provisions of this handbook are applicable to all NASA field installations and the Jet Propulsion Laboratory. Since supply of this handbook is limited, abstracts of the portion or portions applicable to a given requirement will be made for the individual specific needs encountered rather than supplying copies of the handbook as has been past practice.

  15. Space Station Environment Control and Life Support System Pressure Control Pump Assembly Modeling and Analysis

    NASA Technical Reports Server (NTRS)

    Schunk, R. Gregory

    2002-01-01

    This paper presents the Modeling and Analysis of the Space Station Environment Control and Life Support System Pressure Control Pump Assembly (PCPA). The contents include: 1) Integrated PCPA/Manifold Analyses; 2) Manifold Performance Analysis; 3) PCPA Motor Heat Leak Study; and 4) Future Plans. This paper is presented in viewgraph form.

  16. Hypertension guidelines: Evidence-based treatments for maintaining blood pressure control.

    PubMed

    Davis, Leslie Louise

    2015-06-11

    Approximately one in three adults in the United States has hypertension. This article provides an update on the latest JNC-8 guideline for treating hypertension in adults. Emphasis is placed on new and updated information and implications for primary care clinicians to help patients achieve and maintain better blood pressure control.

  17. Design of a versatile pressure control system for gas targets in ion-atom collision studies

    NASA Astrophysics Data System (ADS)

    Fuelling, S.; Bruch, R.

    1993-06-01

    In this work, a unique gas target pressure control system is described which has been developed to measure state selective absolute EUV cross sections subsequent to electron and ion impact on gaseous targets. This system can be used in any type of gas phase experiment using positively or negatively charged and neutral particle beams interacting with atomic and molecular targets.

  18. Cryogenic Pressure Control Modeling for Ellipsoidal Space Tanks in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Hedayat, Ali; Lopez, Alfredo; Grayson, Gary D.; Chandler, Frank O.; Hastings, Leon J.

    2008-01-01

    A computational fluid dynamics (CFD) model is developed to simulate pressure control of an ellipsoidal-shaped liquid hydrogen tank under external heating in low gravity. Pressure control is provided by an axial jet thermodynamic vent system (TVS) centered within the vessel that injects cooler liquid into the tank, mixing the contents and reducing tank pressure. The two-phase cryogenic tank model considers liquid hydrogen in its own vapor with liquid density varying with temperature only and a fully compressible ullage. The axisymmetric model is developed using a custom version of the commercially available FLOW-3D software and simulates low gravity extrapolations of engineering checkout tests performed at Marshall Space Flight Center in 1999 in support of the Solar Thermal Upper Stage Technology Demonstrator (STUSTD) program. Model results illustrate that stable low gravity liquid-gas interfaces are maintained during all phases of the pressure control cycle. Steady and relatively smooth ullage pressurization rates are predicted. This work advances current low gravity CFD modeling capabilities for cryogenic pressure control and aids the development of a low cost CFD-based design process for space hardware.

  19. Pre-clinical evaluation of a 15-valent pneumococcal conjugate vaccine (PCV15-CRM197) in an infant-rhesus monkey immunogenicity model.

    PubMed

    Skinner, Julie M; Indrawati, Lani; Cannon, Jayme; Blue, Jeffrey; Winters, Michael; Macnair, John; Pujar, Narahari; Manger, Walter; Zhang, Yuhua; Antonello, Joseph; Shiver, John; Caulfield, Michael; Heinrichs, Jon H

    2011-11-08

    The incidence of invasive pneumococcal disease (IPD), caused by the approximately 91 serotypes of Streptococcus pneumoniae (PN), varies geographically and temporally as a result of changing epidemiology and vaccination patterns as well as due to regional measurement differences. Prevnar(®) (Pfizer), the first licensed pneumococcal conjugate vaccine (PCV), comprises polysaccharides (PS) from 7 serotypes conjugated to the mutant diphtheria toxin carrier protein, CRM197. In the United States and elsewhere, this vaccine has been highly efficacious in reducing the incidence of IPD caused by vaccine serotypes, however, the incidence of non-vaccine serotypes (e.g., 19A, 22F, and 33F) has increased, resulting in the need for vaccines with higher valencies. In response, 10- and 13-valent PCVs have recently been licensed. To further increase serotype coverage, we have developed a 15-valent PCV containing PS from serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 22F, 23F and 33F conjugated to CRM197 and formulated on aluminum phosphate adjuvant. Vaccine immunogenicity was evaluated in infant rhesus monkeys since they, like human infants, respond poorly to unconjugated PN PS. Infant (2-3 month old) rhesus monkeys were vaccinated three times with PCV-15 or Prevnar(®) at 2 month intervals, and serotype-specific IgG antibodies were measured using a multiarray electrochemiluminescence (ECL) assay. The results indicate that antibody responses to PCV-15 and Prevnar(®) were comparable for the 7 common serotypes and that post-vaccination responses to PCV-15 were >10-fold higher than baseline for the 8 additional serotypes.

  20. Mechanical ventilation in abdominal surgery.

    PubMed

    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) (PEEP<5cmH2O) or no PEEP, may cause alveolar overdistension and repetitive tidal recruitment leading to ventilator-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.

  1. Fuselage ventilation under wind conditions

    NASA Technical Reports Server (NTRS)

    Stuart, J. W.

    1979-01-01

    To determine realistic fuselage ventilation rates for post-crash fires and full-scale fire tests, the effects on wind-about fuselage ventilation rate of various parameters were studied. The parameters investigated were fuselage size and shape, fuselage orientation and proximity to ground, fuselage-opening and location, and wind speed and direction.

  2. Transpired Air Collectors - Ventilation Preheating

    SciTech Connect

    Christensen, C.

    2006-06-22

    Many commercial and industrial buildings have high ventilation rates. Although all that fresh air is great for indoor air quality, heating it can be very expensive. This short (2-page) fact sheet describes a technology available to use solar energy to preheat ventilation air and dramatically reduce utility bills.

  3. Difficult weaning from mechanical ventilation.

    PubMed

    Oh, T E

    1994-07-01

    Weaning from mechanical ventilation may be influenced by factors relating to equipment, techniques and procedures. Criteria to initiate weaning and predictors of weaning outcome are generally unreliable, but mechanical work of breathing, the tidal volume: frequency ratio and the inspiratory pressure: maximal inspiratory pressure ratio may anticipate those likely to fail weaning. The optimal weaning ventilatory mode is not known, but intermittent mandatory ventilation, pressure support ventilation, and continuous positive pressure ventilation are the most commonly used. The resistances of individual components of breathing circuits are extremely important. Blow-by heated humidifiers and ventilators which compensate for the impedances of their inspiratory demand valves impose clinically acceptable spontaneous breathing loads. Close monitoring, adequate respiratory muscle rest, attention to mineral deficiencies, nutrition and pulmonary hygiene are also important parts of the weaning process.

  4. Inhalation therapy in mechanical ventilation

    PubMed Central

    Maccari, Juçara Gasparetto; Teixeira, Cassiano; Gazzana, Marcelo Basso; Savi, Augusto; Dexheimer-Neto, Felippe Leopoldo; Knorst, Marli Maria

    2015-01-01

    Patients with obstructive lung disease often require ventilatory support via invasive or noninvasive mechanical ventilation, depending on the severity of the exacerbation. The use of inhaled bronchodilators can significantly reduce airway resistance, contributing to the improvement of respiratory mechanics and patient-ventilator synchrony. Although various studies have been published on this topic, little is known about the effectiveness of the bronchodilators routinely prescribed for patients on mechanical ventilation or about the deposition of those drugs throughout the lungs. The inhaled bronchodilators most commonly used in ICUs are beta adrenergic agonists and anticholinergics. Various factors might influence the effect of bronchodilators, including ventilation mode, position of the spacer in the circuit, tube size, formulation, drug dose, severity of the disease, and patient-ventilator synchrony. Knowledge of the pharmacological properties of bronchodilators and the appropriate techniques for their administration is fundamental to optimizing the treatment of these patients. PMID:26578139

  5. Particle Size Concentration Distribution and Influences on Exhaled Breath Particles in Mechanically Ventilated Patients

    PubMed Central

    Chen, Yi-Fang; Huang, Sheng-Hsiu; Wang, Yu-Ling; Chen, Chun-Wan

    2014-01-01

    Humans produce exhaled breath particles (EBPs) during various breath activities, such as normal breathing, coughing, talking, and sneezing. Airborne transmission risk exists when EBPs have attached pathogens. Until recently, few investigations had evaluated the size and concentration distributions of EBPs from mechanically ventilated patients with different ventilation mode settings. This study thus broke new ground by not only evaluating the size concentration distributions of EBPs in mechanically ventilated patients, but also investigating the relationship between EBP level and positive expiratory end airway pressure (PEEP), tidal volume, and pneumonia. This investigation recruited mechanically ventilated patients, with and without pneumonia, aged 20 years old and above, from the respiratory intensive care unit of a medical center. Concentration distributions of EBPs from mechanically ventilated patients were analyzed with an optical particle analyzer. This study finds that EBP concentrations from mechanically ventilated patients during normal breathing were in the range 0.47–2,554.04 particles/breath (0.001–4.644 particles/mL). EBP concentrations did not differ significantly between the volume control and pressure control modes of the ventilation settings in the mechanically ventilated patients. The patient EBPs were sized below 5 µm, and 80% of them ranged from 0.3 to 1.0 µm. The EBPs concentrations in patients with high PEEP (> 5 cmH2O) clearly exceeded those in patients with low PEEP (≤ 5 cmH2O). Additionally, a significant negative association existed between pneumonia duration and EBPs concentration. However, tidal volume was not related to EBPs concentration. PMID:24475230

  6. Solar ventilation and tempering

    NASA Astrophysics Data System (ADS)

    Adámek, Karel; Pavlů, Miloš; Bandouch, Milan

    2014-08-01

    The paper presents basic information about solar panels, designed, realized and used for solar ventilation of rooms. Used method of numerical flow simulation gives good overview about warming and flowing of the air in several kinds of realized panels (window, facade, chimney). Yearlong measurements give a good base for calculations of economic return of invested capital. The operation of the system in transient period (spring, autumn) prolongs the period without classical heating of the room or building, in winter the classical heating is supported. In the summer period the system, furnished with chimney, can exhaust inner warm air together with necessary cooling of the system by gravity circulation, only. System needs not any invoiced energy source; it is supplied entirely by solar energy. Large building systems are supported by classical electric fan respectively.

  7. Ventilation and respiratory mechanics.

    PubMed

    Sheel, Andrew William; Romer, Lee M

    2012-04-01

    During dynamic exercise, the healthy pulmonary system faces several major challenges, including decreases in mixed venous oxygen content and increases in mixed venous carbon dioxide. As such, the ventilatory demand is increased, while the rising cardiac output means that blood will have considerably less time in the pulmonary capillaries to accomplish gas exchange. Blood gas homeostasis must be accomplished by precise regulation of alveolar ventilation via medullary neural networks and sensory reflex mechanisms. It is equally important that cardiovascular and pulmonary system responses to exercise be precisely matched to the increase in metabolic requirements, and that the substantial gas transport needs of both respiratory and locomotor muscles be considered. Our article addresses each of these topics with emphasis on the healthy, young adult exercising in normoxia. We review recent evidence concerning how exercise hyperpnea influences sympathetic vasoconstrictor outflow and the effect this might have on the ability to perform muscular work. We also review sex-based differences in lung mechanics.

  8. Estimation of Lung Ventilation

    NASA Astrophysics Data System (ADS)

    Ding, Kai; Cao, Kunlin; Du, Kaifang; Amelon, Ryan; Christensen, Gary E.; Raghavan, Madhavan; Reinhardt, Joseph M.

    Since the primary function of the lung is gas exchange, ventilation can be interpreted as an index of lung function in addition to perfusion. Injury and disease processes can alter lung function on a global and/or a local level. MDCT can be used to acquire multiple static breath-hold CT images of the lung taken at different lung volumes, or with proper respiratory control, 4DCT images of the lung reconstructed at different respiratory phases. Image registration can be applied to this data to estimate a deformation field that transforms the lung from one volume configuration to the other. This deformation field can be analyzed to estimate local lung tissue expansion, calculate voxel-by-voxel intensity change, and make biomechanical measurements. The physiologic significance of the registration-based measures of respiratory function can be established by comparing to more conventional measurements, such as nuclear medicine or contrast wash-in/wash-out studies with CT or MR. An important emerging application of these methods is the detection of pulmonary function change in subjects undergoing radiation therapy (RT) for lung cancer. During RT, treatment is commonly limited to sub-therapeutic doses due to unintended toxicity to normal lung tissue. Measurement of pulmonary function may be useful as a planning tool during RT planning, may be useful for tracking the progression of toxicity to nearby normal tissue during RT, and can be used to evaluate the effectiveness of a treatment post-therapy. This chapter reviews the basic measures to estimate regional ventilation from image registration of CT images, the comparison of them to the existing golden standard and the application in radiation therapy.

  9. Ventilator Associated Pneumonia in Children.

    PubMed

    Chang, Ivy; Schibler, Andreas

    2016-09-01

    Ventilator associated pneumonia (VAP) is a common complication in mechanically ventilated children and adults. There remains much controversy in the literature over the definition, treatment and prevention of VAP. The incidence of VAP is variable, depending on the definition used and can effect up to 12% of ventilated children. For the prevention and reduction of the incidence of VAP, ventilation care bundles are suggested, which include vigorous hand hygiene, head elevation and use of non-invasive ventilation strategies. Diagnosis is mainly based on the clinical presentation with a lung infection occurring after 48hours of mechanical ventilation requiring a change in ventilator settings (mainly increased oxygen requirement, a positive culture of a specimen taken preferentially using a sterile sampling technique either using a bronchoscope or a blind lavage of the airways). A new infiltrate on a chest X ray supports the diagnosis of VAP. For the treatment of VAP, initial broad-spectrum antibiotics should be used followed by a specific antibiotic therapy with a narrow target once the bacterium is confirmed.

  10. Lung ventilation strategies for acute respiratory distress syndrome: a systematic review and network meta-analysis.

    PubMed

    Wang, Changsong; Wang, Xiaoyang; Chi, Chunjie; Guo, Libo; Guo, Lei; Zhao, Nana; Wang, Weiwei; Pi, Xin; Sun, Bo; Lian, Ailing; Shi, Jinghui; Li, Enyou

    2016-03-09

    To identify the best lung ventilation strategy for acute respiratory distress syndrome (ARDS), we performed a network meta-analysis. The Cochrane Central Register of Controlled Trials, EMBASE, MEDLINE, CINAHL, and the Web of Science were searched, and 36 eligible articles were included. Compared with higher tidal volumes with FiO2-guided lower positive end-expiratory pressure [PEEP], the hazard ratios (HRs) for mortality were 0.624 (95% confidence interval (CI) 0.419-0.98) for lower tidal volumes with FiO2-guided lower PEEP and prone positioning and 0.572 (0.34-0.968) for pressure-controlled ventilation with FiO2-guided lower PEEP. Lower tidal volumes with FiO2-guided higher PEEP and prone positioning had the greatest potential to reduce mortality, and the possibility of receiving the first ranking was 61.6%. Permissive hypercapnia, recruitment maneuver, and low airway pressures were most likely to be the worst in terms of all-cause mortality. Compared with higher tidal volumes with FiO2-guided lower PEEP, pressure-controlled ventilation with FiO2-guided lower PEEP and lower tidal volumes with FiO2-guided lower PEEP and prone positioning ventilation are associated with lower mortality in ARDS patients. Lower tidal volumes with FiO2-guided higher PEEP and prone positioning ventilation and lower tidal volumes with pressure-volume (P-V) static curve-guided individual PEEP are potential optimal strategies for ARDS patients.

  11. A care bundle approach for prevention of ventilator-associated pneumonia.

    PubMed

    Rello, J; Afonso, E; Lisboa, T; Ricart, M; Balsera, B; Rovira, A; Valles, J; Diaz, E

    2013-04-01

    Implementation of care bundles for prevention of ventilator-associated pneumonia (VAP) and its impact on patient outcomes requires validation with long-term follow-up. A collaborative multi-centre cohort study was conducted in five Spanish adult intensive-care units. A care bundle approach based on five measures was implemented after a 3-month baseline period, and compliance, VAP rates, intensive-care unit length of stay (ICU LOS) and duration of mechanical ventilation were prospectively recorded for 16 months. There were 149 patients in the baseline period and 885 after the intervention. Compliance with all measures after intervention was <30% (264/885). In spite of this, VAP incidence decreased from 15.5% (23/149) to 11.7% (104/885), after the intervention (p <0.05). This reduction was significantly associated with hand hygiene (OR = 0.35), intra-cuff pressure control (OR = 0.21), oral hygiene (OR = 0.23) and sedation control (OR = 0.51). Use of the care bundle was associated with an incidence risk ratio of VAP of 0.78 (95% CI 0.15-0.99). We documented a reduction of median ICU LOS (from 10 to 6 days) and duration of mechanical ventilation (from 8 to 4 days) for patients with full bundle compliance (intervention period). Efforts on VAP prevention and outcome improvement should focus on achieving higher compliance in hand and oral hygiene, sedation protocols and intracuff pressure control.

  12. 46 CFR 168.15-50 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Accommodations § 168.15-50 Ventilation. (a) All quarters must be adequately ventilated in a manner suitable to the purpose of the space and route of the vessel. (b) When mechanical ventilation is provided for... 46 Shipping 7 2010-10-01 2010-10-01 false Ventilation. 168.15-50 Section 168.15-50 Shipping...

  13. 46 CFR 168.15-50 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Ventilation. 168.15-50 Section 168.15-50 Shipping COAST... Accommodations § 168.15-50 Ventilation. (a) All quarters must be adequately ventilated in a manner suitable to the purpose of the space and route of the vessel. (b) When mechanical ventilation is provided...

  14. 46 CFR 168.15-50 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Ventilation. 168.15-50 Section 168.15-50 Shipping COAST... Accommodations § 168.15-50 Ventilation. (a) All quarters must be adequately ventilated in a manner suitable to the purpose of the space and route of the vessel. (b) When mechanical ventilation is provided...

  15. 46 CFR 168.15-50 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Ventilation. 168.15-50 Section 168.15-50 Shipping COAST... Accommodations § 168.15-50 Ventilation. (a) All quarters must be adequately ventilated in a manner suitable to the purpose of the space and route of the vessel. (b) When mechanical ventilation is provided...

  16. 46 CFR 194.20-5 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Ventilation. 194.20-5 Section 194.20-5 Shipping COAST... Ventilation. (a) Chemical storerooms shall be equipped with a power ventilation system of exhaust type. The... based upon the volume of the compartment. (1) Power ventilation units shall have nonsparking...

  17. 33 CFR 175.201 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Ventilation. 175.201 Section 175... SAFETY EQUIPMENT REQUIREMENTS Ventilation § 175.201 Ventilation. No person may operate a boat built after... unless it is equipped with an operable ventilation system that meets the requirements of 33 CFR...

  18. 33 CFR 175.201 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Ventilation. 175.201 Section 175... SAFETY EQUIPMENT REQUIREMENTS Ventilation § 175.201 Ventilation. No person may operate a boat built after... unless it is equipped with an operable ventilation system that meets the requirements of 33 CFR...

  19. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Crawlspace ventilation. 3285.505... ventilation. (a) A crawlspace with skirting must be provided with ventilation openings. The minimum net area of ventilation openings must not be less than one square foot (ft.2) for every 150 square feet...

  20. 33 CFR 175.201 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Ventilation. 175.201 Section 175... SAFETY EQUIPMENT REQUIREMENTS Ventilation § 175.201 Ventilation. No person may operate a boat built after... unless it is equipped with an operable ventilation system that meets the requirements of 33 CFR...

  1. 46 CFR 168.15-50 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Ventilation. 168.15-50 Section 168.15-50 Shipping COAST... Accommodations § 168.15-50 Ventilation. (a) All quarters must be adequately ventilated in a manner suitable to the purpose of the space and route of the vessel. (b) When mechanical ventilation is provided...

  2. 46 CFR 194.20-5 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Ventilation. 194.20-5 Section 194.20-5 Shipping COAST... Ventilation. (a) Chemical storerooms shall be equipped with a power ventilation system of exhaust type. The... based upon the volume of the compartment. (1) Power ventilation units shall have nonsparking...

  3. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Crawlspace ventilation. 3285.505... ventilation. (a) A crawlspace with skirting must be provided with ventilation openings. The minimum net area of ventilation openings must not be less than one square foot (ft.2) for every 150 square feet...

  4. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Crawlspace ventilation. 3285.505... ventilation. (a) A crawlspace with skirting must be provided with ventilation openings. The minimum net area of ventilation openings must not be less than one square foot (ft.2) for every 150 square feet...

  5. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Crawlspace ventilation. 3285.505... ventilation. (a) A crawlspace with skirting must be provided with ventilation openings. The minimum net area of ventilation openings must not be less than one square foot (ft.2) for every 150 square feet...

  6. 30 CFR 75.333 - Ventilation controls.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Ventilation controls. 75.333 Section 75.333... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.333 Ventilation controls. (a) For... ventilation control devices constructed after November 15, 1992, shall be built and maintained— (1)...

  7. 30 CFR 75.333 - Ventilation controls.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Ventilation controls. 75.333 Section 75.333... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.333 Ventilation controls. (a) For... ventilation control devices constructed after November 15, 1992, shall be built and maintained— (1)...

  8. Preoperational test report, vent building ventilation system

    SciTech Connect

    Clifton, F.T.

    1997-11-04

    This represents a preoperational test report for Vent Building Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides Heating, Ventilation, and Air Conditioning (HVAC) for the W-030 Ventilation Building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  9. 30 CFR 57.8520 - Ventilation plan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Ventilation plan. 57.8520 Section 57.8520... Underground Only § 57.8520 Ventilation plan. A plan of the mine ventilation system shall be set out by the... ventilation plan or revisions thereto shall be submitted to the District Manager for review and comments...

  10. 30 CFR 57.8520 - Ventilation plan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Ventilation plan. 57.8520 Section 57.8520... Underground Only § 57.8520 Ventilation plan. A plan of the mine ventilation system shall be set out by the... ventilation plan or revisions thereto shall be submitted to the District Manager for review and comments...

  11. 46 CFR 111.105-21 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation. 111.105-21 Section 111.105-21 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Hazardous Locations § 111.105-21 Ventilation. A ventilation duct which ventilates a...

  12. 30 CFR 57.8520 - Ventilation plan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Ventilation plan. 57.8520 Section 57.8520... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8520 Ventilation plan. A plan of the mine ventilation system shall be set out by...

  13. 6. VIEW LOOKING SOUTHEAST AT VENTILATION EQUIPMENT IN SOUTH VENTILATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. VIEW LOOKING SOUTHEAST AT VENTILATION EQUIPMENT IN SOUTH VENTILATION HOUSE. THIS AIR CONDITIONING SYSTEM WAS INSTALLED BY PARKS-CRAMER COMPANY OF FITCHBURG, MASSACHUSETTS WHEN THE MILL WAS CONSTRUCTED IN 1923-24. ONE AIR WASHER AND FAN ROOM EXTERIOR IS VISIBLE ON THE RIGHT. THE DUCTS FROM BOTH FAN ROOMS (CURVED METAL STRUCTURES AT CENTER AND LEFT OF PHOTO) ARE CONNECTED TO A COMMON AIR SHAFT. - Stark Mill, 117 Corinth Road, Hogansville, Troup County, GA

  14. Acculturation, Medication Adherence, Lifestyle Behaviors, and Blood Pressure Control Among Arab Americans

    PubMed Central

    Tailakh, Ayman K.; Evangelista, Lorraine S.; Morisky, Donald E.; Mentes, Janet C.; Pike, Nancy A.; Phillips, Linda R.

    2015-01-01

    Purpose The aim of this study was to examine the relationship between acculturation, medication adherence, lifestyle behaviors (e.g., physical activity, nutrition, weight control), and blood pressure control among hypertensive Arab Americans. Design The study utilized a cross-sectional descriptive design. A convenience sample of 126 participants completed questionnaires and had measures of blood pressure, weight, and height. Forty-six participants were hypertensive and were included in the analysis. Results Only 29.2% of participants reported high medication adherence. High medication adherence was associated with lower diastolic blood pressure, eating a healthy diet, and following lifestyle modifications. Acculturation was significantly associated with physical activity and body mass index. Conclusion Our study found that acculturated participants were more adherent to medications and physical activity and had better blood pressure control. Further studies are needed to explore how acculturation improves adherence and what factors contribute to better adherence in order to design culturally sensitive interventions. PMID:24848347

  15. Modeling Ullage Dynamics of Tank Pressure Control Experiment during Jet Mixing in Microgravity

    NASA Technical Reports Server (NTRS)

    Kartuzova, O.; Kassemi, M.

    2016-01-01

    A CFD model for simulating the fluid dynamics of the jet induced mixing process is utilized in this paper to model the pressure control portion of the Tank Pressure Control Experiment (TPCE) in microgravity1. The Volume of Fluid (VOF) method is used for modeling the dynamics of the interface during mixing. The simulations were performed at a range of jet Weber numbers from non-penetrating to fully penetrating. Two different initial ullage positions were considered. The computational results for the jet-ullage interaction are compared with still images from the video of the experiment. A qualitative comparison shows that the CFD model was able to capture the main features of the interfacial dynamics, as well as the jet penetration of the ullage.

  16. [Pressure control system for the hermetically sealed cabin of the recoverable satellite].

    PubMed

    Sun, J; Yao, S; Zhang, X; Zhang, F; Zheng, C; Fu, L

    1998-06-01

    There are many precision instruments and equipment for scientific researches and experiments in the hermetically sealed cabin of satellite. Appropriate pressure must be controlled in the cabin in order to ensure the instruments and equipment from the adverse space environment. This paper describes a pressure control system for the hermetically sealed cabin in the recoverable scientific detect and experimental satellite. The cabin pressure is regulated automatically into the specific levels by venting or supplying the air from or to the cabin during launch, on orbit and before reentry of the satellite. The system has low mass, low power consumption and high reliability. It was used successfully in the recoverable satellite first in September 1987 and had been used many times since then. It is the first active pressure control system for the hermetically sealed cabin of the satellite in China.

  17. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 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...

  18. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 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...

  19. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 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...

  20. Equivalence in Ventilation and Indoor Air Quality

    SciTech Connect

    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.

  1. Salt intake, knowledge of salt intake, and blood pressure control in Chinese hypertensive patients.

    PubMed

    Qin, Yu; Li, Ting; Lou, Peian; Chang, Guiqiu; Zhang, Pan; Chen, Peipei; Qiao, Cheng; Dong, Zongmei

    2014-12-01

    A cross-sectional study involving 2502 subjects was conducted to evaluate salt intake, knowledge of salt intake, and blood pressure control in hypertensive patients. The blood pressure control rate was 33.5% among the hypertensive patients. Of the patients, 69.9% had salt intake higher than 6 g/d. Overall 35.0% knew the recommended salt intake, and 94.9% knew that "excess salt intake can result in hypertension." Altogether, 85.8% of patients had received health education related to a low-salt diet at some time. Patients who consumed less than 6 g/d of salt had a higher control rate than those who consumed more than 6 g/d (48.7% vs. 27.0%; χ(2) = 111.0; P < .001). Patients with knowledge of the recommended salt intake had a higher control rate than those without (45.8% vs. 26.9%; χ(2) = 91.3; P < .001). Our findings suggest a high salt intake and low blood pressure control rate among Chinese hypertensive patients. Knowledge of recommended salt intake is inappropriate for patients with education of a low-salt diet.

  2. LH2 tank pressure control by thermodynamic vent system (TVS) at zero gravity

    NASA Astrophysics Data System (ADS)

    Wang, B.; Huang, Y. H.; Chen, Z. C.; Wu, J. Y.; Li, P.; Sun, P. J.

    2017-02-01

    Thermodynamic vent system (TVS) is employed for pressure control of propellant tanks at zero gravity. An analytical lumped parameter model is developed to predict pressure variation in an 18.09 m3 liquid hydrogen tank equipped with TVS. Mathematical simulations are carried out assuming tank is filled up to 75% volume (liquid mass equals to 945 kg) and is subjected to heat flux of 0.76 W/m2. Tank pressure controls at 165.5-172.4, 165.5-179.3 and 165.5-182.2 kPa are compared with reference to number of vent cycles, vent duration per cycle and loss of hydrogen. Analysis results indicate that the number of vent cycles significantly decreases from 62 to 21 when tank pressure control increases from 6.9 to 20.4 kPa. Also, duration of vent cycle increases from 63 to 152 and cycle duration decreases from 3920 to 3200 s. Further, the analysis result suggests that LH2 evaporation loss per day decreases from 0.17 to 0.14%. Based on the results of analysis, TVS is found effective in controlling the propellant tank pressure in zero gravity.

  3. Basic concepts in mechanical ventilation.

    PubMed

    Carbery, Catherine

    2008-03-01

    Mechanical ventilatory support is a major component of the clinical management of critically ill patients admitted into intensive care. Closely linked with the developments within critical care medicine, the use of ventilatory support has been increasing since the polio epidemics in the 1950s (Lassen 1953). Initially used to provide controlled mandatory ventilation, today with advances in technology, most mechanical ventilators are triggered by the patient, increasing the awareness of the complexity of patient/ventilator interaction (Tobin 1994). Though ventilator appearance and design may have changed quite significantly and the variety of options for support extensive, the basic concepts of mechanical ventilatory support of the critically ill patient remains unchanged. This paper aims to outline these concepts so as to gain a better understanding of mechanical ventilatory support.

  4. Ventilation Model and Analysis Report

    SciTech Connect

    V. Chipman

    2003-07-18

    This model and analysis report develops, validates, and implements a conceptual model for heat transfer in and around a ventilated emplacement drift. This conceptual model includes thermal radiation between the waste package and the drift wall, convection from the waste package and drift wall surfaces into the flowing air, and conduction in the surrounding host rock. These heat transfer processes are coupled and vary both temporally and spatially, so numerical and analytical methods are used to implement the mathematical equations which describe the conceptual model. These numerical and analytical methods predict the transient response of the system, at the drift scale, in terms of spatially varying temperatures and ventilation efficiencies. The ventilation efficiency describes the effectiveness of the ventilation process in removing radionuclide decay heat from the drift environment. An alternative conceptual model is also developed which evaluates the influence of water and water vapor mass transport on the ventilation efficiency. These effects are described using analytical methods which bound the contribution of latent heat to the system, quantify the effects of varying degrees of host rock saturation (and hence host rock thermal conductivity) on the ventilation efficiency, and evaluate the effects of vapor and enhanced vapor diffusion on the host rock thermal conductivity.

  5. High pneumonia lifetime-ever incidence in Beijing children compared with locations in other countries, and implications for national PCV and Hib vaccination

    PubMed Central

    Qu, Fang; Sun, Yuexia; Sundell, Jan

    2017-01-01

    Objectives To compare the proportion of Beijing children who have ever had pneumonia (%Pneumonia) to those in other locations, and to estimate by how much national vaccine coverage with Pneumococcal Conjugate Vaccine (PCV) and Haemophilus Influenzae Type b (Hib) could reduce Beijing %Pneumonia. Methods %Pneumonia was obtained for each age group from 1 to 8 years inclusive from 5,876 responses to a cross-sectional questionnaire. Literature searches were conducted for world-wide reports of %Pneumonia. Previous vaccine trials conducted worldwide were used to estimate the pneumococcal (S. pneumoniae) and Hib (H. influenzae) burdens and %Pneumonia as well as the potential for PCV and Hib vaccines to reduce Beijing children’s %Pneumonia. Findings The majority of pneumonia cases occurred by the age of three. The cumulative %Pneumonia for 3–8 year-old Beijing children, 26.9%, was only slightly higher than the 25.4% for the discrete 3 year-old age group, similar to trends for Tianjin (China) and Texas (USA). Beijing’s %Pneumonia is disproportionally high relative to its Gross National Income (GNI) per capita, and markedly higher than %Pneumonia in the US and other high GNI per capita countries. Chinese diagnostic guidelines recommend chest X-ray confirmation while most other countries discourage it in favor of clinical diagnosis. Literature review shows that chest X-ray confirmation returns far fewer pneumonia diagnoses than clinical diagnosis. Accordingly, Beijing’s %Pneumonia is likely higher than indicated by raw numbers. Vaccine trials suggest that national PCV and Hib vaccination could reduce Beijing’s %Pneumonia from 26.9% to 19.7% and 24.9% respectively. Conclusion National PCV and Hib vaccination programs would substantially reduce Beijing children’s pneumonia incidence. PMID:28166256

  6. Immunogenicity differences of a 15-valent pneumococcal polysaccharide conjugate vaccine (PCV15) based on vaccine dose, route of immunization and mouse strain.

    PubMed

    Caro-Aguilar, Ivette; Indrawati, Lani; Kaufhold, Robin M; Gaunt, Christine; Zhang, Yuhua; Nawrocki, Denise K; Giovarelli, Cecilia; Winters, Michael A; Smith, William J; Heinrichs, Jon; Skinner, Julie M

    2017-02-07

    Pneumococcal disease continues to be a medical need even with very effective vaccines on the market. Globally, there are extensive research efforts to improve serotype coverage with novel vaccines; therefore, conducting preclinical studies in different animal models becomes essential. The work presented herein focuses on evaluating a 15-valent pneumococcal conjugate vaccine (PCV15) in mice. Initially we evaluated several doses of PCV15 in Balb/c mice. The optimal vaccine dose was determined to be 0.4μg per pneumococcal polysaccharide (PS) (0.8μg of 6B) for subsequent studies. This PS dose was chosen for PCV evaluation in mice based on antibody levels determined by multiplexed electrochemiluminescent (ECL) assays, T-cell responses following in vitro stimulation with CRM197 peptides and protection from pneumococcal challenge. We then selected four mouse strains for evaluation: Balb/c, C3H/HeN, CD1 and Swiss Webster (SW), immunized with PCV15 by either intraperitoneal (IP) or intramuscular (IM) routes. We assessed IgG responses by ECL assays and functional antibody activity by multiplexed opsonophagocytic assays (MOPA). Every mouse strain evaluated responded to all 15 serotypes contained in the vaccine. Mice tended to have lower responses to serotypes 6B, 23F and 33F. The IP route of immunization resulted in higher antibody titers for most serotypes in Balb/c, C3H and SW. CD1 mice tended to respond similarly for most serotypes, regardless of route of immunization. Similar trends were observed with the four mouse strains when evaluating functional antibody activity. Given the differences in antibody responses based on mouse strain and route of immunization, it is critical to evaluate pneumococcal vaccines in multiple animal models to determine the optimal formulation before moving to clinical trials.

  7. Effectiveness of the 10-Valent Pneumococcal Conjugate Vaccine (PCV-10) in Children in Chile: A Nested Case-Control Study Using Nationwide Pneumonia Morbidity and Mortality Surveillance Data

    PubMed Central

    Toscano, Cristiana M.; Alencar, Gizelton P.; Alvarez, Andrés; Valenzuela, Maria T.; Andrus, Jon; del Aguila, Roberto; Hormazábal, Juan C.; Araya, Pamela; Pidal, Paola; Matus, Cuauhtemoc R.; de Oliveira, Lucia H.

    2016-01-01

    Background The ten-valent pneumococcal conjugate vaccine (PCV10) was introduced into the Chilean National Immunization Program (NIP) in January 2011 with a 3+1 schedule (2, 4, 6 and 12 months) without catch-up vaccination. We evaluated the effectiveness of PCV10 on pneumonia morbidity and mortality among infants during the first two years after vaccine introduction. Methods This is a population-based nested case-control study using four merged nationwide case-based electronic health data registries: live birth, vaccination, hospitalization and mortality. Children born in 2010 and 2011 were followed from two moths of age for a period of two years. Using four different case definitions of pneumonia hospitalization and/or mortality (all-cause and pneumonia related deaths), all cases and four randomly selected matched controls per case were selected. Controls were matched to cases on analysis time. Vaccination status was then assessed. Vaccine effectiveness (VE) was estimated using conditional logistic regression. Results There were a total of 497,996 children in the 2010 and 2011 Chilean live-birth cohorts. PCV10 VE was 11.2% (95%CI 8.5–13.6) when all pneumonia hospitalizations and deaths were used to define cases. VE increased to 20.7 (95%CI 17.3–23.8) when ICD10 codes used to denote viral pneumonia were excluded from the case definition. VE estimates on pneumonia deaths and all-cause deaths were 71.5 (95%CI 9.0–91.8) and 34.8 (95% CI 23.7–44.4), respectively. Conclusion PCV10 vaccination substantially reduced the number of hospitalizations due to pneumonia and deaths due to pneumonia and to all-causes over this study period. Our findings also reinforce the importance of having quality health information systems for measuring VE. PMID:27058873

  8. Analyzing the Impact of Different Pcv Calibration Models on Height Determination Using Gps/Glonass Observations from Asg-Eupos Network

    NASA Astrophysics Data System (ADS)

    Dawidowicz, Karol

    2014-12-01

    The integration of GPS with GLONASS is very important in satellite-based positioning because it can clearly improve reliability and availability. However, unlike GPS, GLONASS satellites transmit signals at different frequencies. This results in significant difficulties in modeling and ambiguity resolution for integrated GNSS positioning. There are also some difficulties related to the antenna Phase Center Variations (PCV) problem because, as is well known, the PCV is dependent on the received signal frequency dependent. Thus, processing simultaneous observations from different positioning systems, e.g. GPS and GLONASS, we can expect complications resulting from the different structure of signals and differences in satellite constellations. The ASG-EUPOS multifunctional system for precise satellite positioning is a part of the EUPOS project involving countries of Central and Eastern Europe. The number of its users is increasing rapidly. Currently 31 of 101 reference stations are equipped with GPS/GLONASS receivers and the number is still increasing. The aim of this paper is to study the height solution differences caused by using different PCV calibration models in integrated GPS/GLONASS observation processing. Studies were conducted based on the datasets from the ASG-EUPOS network. Since the study was intended to evaluate the impact on height determination from the users' point of view, a so-called "commercial" software was chosen for post-processing. The analysis was done in a baseline mode: 3 days of GNSS data collected with three different receivers and antennas were used. For the purposes of research the daily observations were divided into different sessions with a session length of one hour. The results show that switching between relative and absolute PCV models may cause an obvious effect on height determination. This issue is particularly important when mixed GPS/GLONASS observations are post-processed.

  9. Hospitalization for Invasive Pneumococcal Disease in a National Sample of Children with Sickle Cell Disease Before and After PCV7 Licensure

    PubMed Central

    McCavit, Timothy L.; Xuan, Lei; Zhang, Song; Flores, Glenn; Quinn, Charles T.

    2012-01-01

    Objective To estimate national hospitalization rates for invasive pneumococcal disease (IPD) in children with sickle cell disease (SCD) before and after the 2000 licensure of the heptavalent pneumococcal conjugate vaccine (PCV7). Procedure We performed a retrospective trend analysis of the 1994-2007 Nationwide Inpatient Sample databases. Hospitalizations involving children with SCD and IPD were identified by ICD-9CM code. The primary outcomes, the annual hospitalization rate for IPD in children with SCD and the proportion of hospitalizations for IPD per 100 total SCD hospitalizations, were analyzed using multivariable linear regression and contingency analysis, respectively. Results A total of 1,242 hospitalizations for IPD in SCD patients were identified from 1994-2007, with a mortality rate of 2.4%. The national mean annual rate of IPD hospitalization decreased by 65%, from 131.8 cases/year from 1994-2000 to 45.5 cases/year from 2001-2007 (p=0.001). The national proportion of hospitalizations for IPD per 100 total SCD hospitalizations decreased from 0.4 to 0.15 (p<0.0001) over the same interval. Following PCV7 licensure, the mean annual cumulative hospital days and cumulative hospital charges decreased nationally by 53% and 36%, respectively. Conclusion In a national sample, PCV7 licensure is temporally associated with a nearly three fold reduction in IPD hospitalizations in children with SCD. PMID:21793185

  10. Decrease in Hospitalizations for Pneumonia in Children under Five Years of Age in an Indian Reservation in Panama after the Introduction of the Heptavalent Pneumococcal Conjugate Vaccine (PCV7)

    PubMed Central

    Nieto Guevara, Javier; Daza, Carlos

    2013-01-01

    This study quantifies the impact of Heptavalent-Pneumococcal Conjugate Vaccine (PCV7) in Panama on indigenous children younger than 5 years old, based on clinical pneumonia cases. This study demonstrates a significant 41.2% reduction in hospitalizations and 38.6% reduction in referrals for pneumonia following the introduction of PCV7. Burden of disease from pneumonia appears reduced in the ≤12-month- and 13-to-24-month-old groups. PMID:23762081

  11. Injurious mechanical ventilation in the normal lung causes a progressive pathologic change in dynamic alveolar mechanics

    PubMed Central

    Pavone, Lucio A; Albert, Scott; Carney, David; Gatto, Louis A; Halter, Jeffrey M; Nieman, Gary F

    2007-01-01

    Introduction Acute respiratory distress syndrome causes a heterogeneous lung injury, and without protective mechanical ventilation a secondary ventilator-induced lung injury can occur. To ventilate noncompliant lung regions, high inflation pressures are required to 'pop open' the injured alveoli. The temporal impact, however, of these elevated pressures on normal alveolar mechanics (that is, the dynamic change in alveolar size and shape during ventilation) is unknown. In the present study we found that ventilating the normal lung with high peak pressure (45 cmH20) and low positive end-expiratory pressure (PEEP of 3 cmH2O) did not initially result in altered alveolar mechanics, but alveolar instability developed over time. Methods Anesthetized rats underwent tracheostomy, were placed on pressure control ventilation, and underwent sternotomy. Rats were then assigned to one of three ventilation strategies: control group (n = 3, Pcontrol = 14 cmH2O, PEEP = 3 cmH2O), high pressure/low PEEP group (n = 6, Pcontrol = 45 cmH2O, PEEP = 3 cmH2O), and high pressure/high PEEP group (n = 5, Pcontrol = 45 cmH2O, PEEP = 10 cmH2O). In vivo microscopic footage of subpleural alveolar stability (that is, recruitment/derecruitment) was taken at baseline and than every 15 minutes for 90 minutes following ventilator adjustments. Alveolar recruitment/derecruitment was determined by measuring the area of individual alveoli at peak inspiration (I) and end expiration (E) by computer image analysis. Alveolar recruitment/derecruitment was quantified by the percentage change in alveolar area during tidal ventilation (%I – EΔ). Results Alveoli were stable in the control group for the entire experiment (low %I – EΔ). Alveoli in the high pressure/low PEEP group were initially stable (low %I – EΔ), but with time alveolar recruitment/derecruitment developed. The development of alveolar instability in the high pressure/low PEEP group was associated with histologic lung injury. Conclusion A

  12. Inspiratory work and response times of a modified pediatric volume ventilator during synchronized intermittent mandatory ventilation and pressure support ventilation.

    PubMed

    Martin, L D; Rafferty, J F; Wetzel, R C; Gioia, F R

    1989-12-01

    Volume ventilation by demand flow ventilators significantly increases work of breathing during inspiration. Although various ventilator modifications and different modes of ventilation have been developed, there have been few studies regarding imposed work of breathing in infants and children. This study was designed to evaluate several modifications of a commercially available demand flow ventilator designed to shorten response time (tr) and decrease the imposed work (Wi) involved in opening the demand valve. Minimum withdrawal volume (Vmin), maximum negative pressure (P mneg), and tr were measured. Wi was defined as the product of Vmin and P mneg. Seven Siemens Servo 900C ventilators were tested under 16 different trial conditions with four variables: 1) mode of ventilation (synchronized intermittent mandatory ventilation [SIMV] vs. pressure support ventilation [PSV]); 2) caliber of circuit tubing (adult vs. pediatric); 3) location of airway pressure monitor (distal vs. proximal); and 4) ventilator trigger sensitivity (0 cm H2O--high vs. -2 cm H2O--low). Vmin, Pmneg, and Wi were all decreased (P less than .05) while tr was unaffected by changing ventilator trigger sensitivity from low to high. Wi was decreased by pediatric tubing and proximal airway pressure monitoring only when low trigger sensitivity was used. PSV and proximal airway monitoring shortened tr. The authors conclude that the use of pediatric circuit tubing and proximal airway pressure monitoring with a Siemens Servo 900C ventilator significantly improved ventilator performance.

  13. Blood Pressure Control in Hypertensive Patients in the "Hiperdia Program": A Territory-Based Study

    PubMed Central

    de Souza, Clarita Silva; Stein, Airton Tetelbom; Bastos, Gisele Alsina Nader; Pellanda, Lucia Campos

    2014-01-01

    Background Systemic hypertension is highly prevalent and an important risk factor for cardiovascular events. Blood pressure control in hypertensive patients enrolled in the Hiperdia Program, a program of the Single Health System for the follow-up and monitoring of hypertensive patients, is still far below the desired level. Objective To describe the epidemiological profile and to assess blood pressure control of patients enrolled in Hiperdia, in the city of Novo Hamburgo (State of Rio Grande do Sul, Brazil). Methods Cross-sectional study with a stratified cluster random sample, including 383 adults enrolled in the Hiperdia Program of the 15 Basic Health Units of the city of Porto Alegre, conducted between 2010 and 2011. Controlled blood pressure was defined as ≤140 mmHg × 90 mmHg. The hypertensive patients were interviewed and their blood pressure was measured using a calibrated aneroid device. Prevalence ratios (PR) with 95% confidence interval, Wald's χ2 test, and simple and multiple Poisson regression were used in the statistical analysis. Results The mean age was 63 ± 10 years, and most of the patients were females belonging to social class C, with a low level of education, a sedentary lifestyle, and family history positive for systemic hypertension. Diabetes mellitus (DM) was observed in 31%; adherence to the antihypertensive treatment in 54.3%; and 33.7% had their blood pressure controlled. DM was strongly associated with inadequate BP control, with only 15.7% of the diabetics showing BP considered as controlled. Conclusion Even for hypertensive patients enrolled in the Hiperdia Program, BP control is not satisfactorily reached or sustained. Diabetic hypertensive patients show the most inappropriate BP control. PMID:25004419

  14. Relationship between Glaucoma Drainage Device Size and Intraocular Pressure Control: Does Size Matter?

    PubMed Central

    Rodgers, Cooper D; Meyer, Alissa M

    2017-01-01

    ABSTRACT There is ambiguity in the literature regarding whether a larger glaucoma drainage device (GDD) achieves a lower long-term intraocular pressure (IOP). There is some evidence on both sides, but overall there seems to be an optimal surface area of approximately 200-250 mm2 beyond which there may be little advantage to increasing the plate size for most patients. How to cite this article Rodgers CD, Meyer AM, Sherwood MB. Relationship between Glaucoma Drainage Device Size and Intraocular Pressure Control: Does Size Matter? J Curr Glaucoma Pract 2017;11(1):1-2. PMID:28138210

  15. Assessment of Blood Pressure Control among Hypertensive Patients in Southwest Ethiopia

    PubMed Central

    Asgedom, Solomon Woldegebriel; Gudina, Esayas Kebede; Desse, Tigestu Alemu

    2016-01-01

    Background The rate of blood pressure control among hypertensive patients is poor and the reasons for poor control of blood pressure remain poorly understood globally. Objective To assess the rate of blood pressure control among adult hypertensive patients at Jimma University Specialized Hospital. Materials and Methods We conducted a hospital based cross sectional study among adult hypertensive patients at Jimma University Specialized Hospital hypertension clinic from March 4, 2015 to April 3, 2015. Data on sociodemographic characteristics of the participants and adherence to antihypertensive medication(s) were collected from patients by face to face interview using a pretested structured questionnaire. Comorbidities, antihypertensive medication(s) and blood pressure measurements were collected retrospectively from medical records. Medication adherence was assessed using Morisky’s Medication Adherence Scale-8 score. We did the statistical analysis using chi-square test and binary logistic regression with level of α set at 0.05. Statistical significance was considered for variables with p<0.05. Results Out of 311 participants, 286 patients were eligible and were studied. More than half, 154 (53.8%), of the participants were males. The mean age of the participants was 54.8± 12.6 years (range 26 to 94). The majority, 196 (68.53%), of the participants were taking more than one antihypertensive medication. More than one third (39.5%) of the participants were non adherent to their medication(s). The rate of blood pressure control was 50.3%. In a univariate logistic regression analyses, age ≥65 years old (P = 0.008), physical inactivity (p<0.001), chat chewing (P<0.001), adding salt to food (P<0.001), and coffee use (P<0.001) are significantly associated with uncontrolled blood pressure Conclusion Almost half of the hypertensive patients on follow up had uncontrolled blood pressure. We recommend better health education and care of patients to improve the rate of

  16. Attenuated Total Reflection (ATR) Sampling in Infrared Spectroscopy of Heterogeneous Materials Requires Reproducible Pressure Control.

    PubMed

    Lu, Zhenyu; Cassidy, Brianna M; DeJong, Stephanie A; Belliveau, Raymond G; Myrick, Michael L; Morgan, Stephen L

    2017-01-01

    Attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy, in which the sample is pressed against an internal reflection element, is a popular technique for rapid IR spectral collection. However, depending on the accessory design, the pressure applied to the sample is not always well controlled. While collecting data from fabrics with heterogeneous coatings, we have observed systematic pressure-dependent changes in spectra that can be eliminated by more reproducible pressure control. We also described a pressure sensor adapted to work with an ATR tower to enable more precise control of pressure during ATR sampling.

  17. Residential ventilation standards scoping study

    SciTech Connect

    McKone, Thomas E.; Sherman, Max H.

    2003-10-01

    The goals of this scoping study are to identify research needed to develop improved ventilation standards for California's Title 24 Building Energy Efficiency Standards. The 2008 Title 24 Standards are the primary target for the outcome of this research, but this scoping study is not limited to that timeframe. We prepared this scoping study to provide the California Energy Commission with broad and flexible options for developing a research plan to advance the standards. This document presents the findings of a scoping study commissioned by the Public Interest Energy Research (PIER) program of the California Energy Commission to determine what research is necessary to develop new residential ventilation requirements for California. This study is one of three companion efforts needed to complete the job of determining the ventilation needs of California residences, determining the bases for setting residential ventilation requirements, and determining appropriate ventilation technologies to meet these needs and requirements in an energy efficient manner. Rather than providing research results, this scoping study identifies important research questions along with the level of effort necessary to address these questions and the costs, risks, and benefits of pursuing alternative research questions. In approaching these questions and corresponding levels of effort, feasibility and timing were important considerations. The Commission has specified Summer 2005 as the latest date for completing this research in time to update the 2008 version of California's Energy Code (Title 24).

  18. Comparison of prophylactic effects of polyurethane cylindrical or tapered cuff and polyvinyl chloride cuff endotracheal tubes on ventilator-associated pneumonia.

    PubMed

    Mahmoodpoor, Ata; Peyrovi-far, Ali; Hamishehkar, Hadi; Bakhtyiari, Zhaleh; Mirinezhad, Mir Mousa; Hamidi, Masoud; Golzari, Samad Eslam Jamal

    2013-08-07

    Because microaspiration of contaminated supraglottic secretions past the endotracheal tube cuff is considered to be central in the pathogenesis of pneumonia, improved design of tracheal tubes with new cuff material and shape have reduced the size and number of folds, which together with the addition of suction ports above the cuff to drain pooled subglottic secretions leads to reduced aspiration of oropharyngeal secretions. So we conducted a study to compare the prophylactic effects of polyurethane-cylindrical or tapered cuff and polyvinyl chloride cuff endotracheal tubes (ETT) on ventilator-associated pneumonia. This randomized clinical trial was carried out in a 12 bed surgical intensive care unit. 96 patients expected to require mechanical ventilation more than 96 hours were randomly allocated to one of three following groups: Polyvinyl chloride cuff (PCV) ETT, Polyurethane (PU) cylindrical Sealguard ETT and PU Taperguard ETT. Cuff pressure monitored every three hours 3 days in all patients. Mean cuff pressure didn't have significant difference between three groups during 72 hours. Pneumonia was seen in 11 patients (34%) in group PVC, 8 (25%) in Sealguard and 7 (21%) in Taperguard group. Changes in mean cuff pressure between Sealguard and PVC tubes and also between Taperguard and PVC tubes did not show any significant difference. There was no significant difference in overinflation between three groups. The use of ETT with PU material results in reducing ventilator-associated pneumonia compared to ETT with PVC cuff. In PU tubes Taperguard has less incidence of ventilator-associated pneumonia compared to Sealguard tubes.

  19. Assisted mechanical ventilation: the future is now!

    PubMed

    Kacmarek, Robert M; Pirrone, Massimiliano; Berra, Lorenzo

    2015-07-29

    Assisted ventilation is a highly complex process that requires an intimate interaction between the ventilator and the patient. The complexity of this form of ventilation is frequently underappreciated by the bedside clinician. In assisted mechanical ventilation, regardless of the specific mode, the ventilator's gas delivery pattern and the patient's breathing pattern must match near perfectly or asynchrony between the patient and the ventilator occurs. Asynchrony can be categorized into four general types: flow asynchrony; trigger asynchrony; cycle asynchrony; and mode asynchrony. In an article recently published in BMC Anesthesiology, Hodane et al. have demonstrated reduced asynchrony during assisted ventilation with Neurally Adjusted Ventilatory Assist (NAVA) as compared to pressure support ventilation (PSV). These findings add to the growing volume of data indicating that modes of ventilation that provide proportional assistance to ventilation - e.g., NAVA and Proportional Assist Ventilation (PAV) - markedly reduce asynchrony. As it becomes more accepted that the respiratory center of the patient in most circumstances is the most appropriate determinant of ventilatory pattern and as the negative outcome effects of patient-ventilator asynchrony become ever more recognized, we can expect NAVA and PAV to become the preferred modes of assisted ventilation!

  20. Systolic blood pressure control among individuals with Type 2 Diabetes: A comparative effectiveness analysis of three interventions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intensive lifestyle management or frequent goal-based monitoring with pharmacological management can be successful strategies for blood pressure control in overweight and obese adults with type 2 diabetes....

  1. Chocolate Classification by an Electronic Nose with Pressure Controlled Generated Stimulation

    PubMed Central

    Valdez, Luis F.; Gutiérrez, Juan Manuel

    2016-01-01

    In this work, we will analyze the response of a Metal Oxide Gas Sensor (MOGS) array to a flow controlled stimulus generated in a pressure controlled canister produced by a homemade olfactometer to build an E-nose. The built E-nose is capable of chocolate identification between the 26 analyzed chocolate bar samples and four features recognition (chocolate type, extra ingredient, sweetener and expiration date status). The data analysis tools used were Principal Components Analysis (PCA) and Artificial Neural Networks (ANNs). The chocolate identification E-nose average classification rate was of 81.3% with 0.99 accuracy (Acc), 0.86 precision (Prc), 0.84 sensitivity (Sen) and 0.99 specificity (Spe) for test. The chocolate feature recognition E-nose gives a classification rate of 85.36% with 0.96 Acc, 0.86 Prc, 0.85 Sen and 0.96 Spe. In addition, a preliminary sample aging analysis was made. The results prove the pressure controlled generated stimulus is reliable for this type of studies. PMID:27775628

  2. Chocolate Classification by an Electronic Nose with Pressure Controlled Generated Stimulation.

    PubMed

    Valdez, Luis F; Gutiérrez, Juan Manuel

    2016-10-20

    In this work, we will analyze the response of a Metal Oxide Gas Sensor (MOGS) array to a flow controlled stimulus generated in a pressure controlled canister produced by a homemade olfactometer to build an E-nose. The built E-nose is capable of chocolate identification between the 26 analyzed chocolate bar samples and four features recognition (chocolate type, extra ingredient, sweetener and expiration date status). The data analysis tools used were Principal Components Analysis (PCA) and Artificial Neural Networks (ANNs). The chocolate identification E-nose average classification rate was of 81.3% with 0.99 accuracy (Acc), 0.86 precision (Prc), 0.84 sensitivity (Sen) and 0.99 specificity (Spe) for test. The chocolate feature recognition E-nose gives a classification rate of 85.36% with 0.96 Acc, 0.86 Prc, 0.85 Sen and 0.96 Spe. In addition, a preliminary sample aging analysis was made. The results prove the pressure controlled generated stimulus is reliable for this type of studies.

  3. Shunt Overdrainage Caused by Displacement of the Pressure Control Cam after Pressure Adjustment

    PubMed Central

    Kim, Su-Ho; Lee, Min-Seok; Suh, Sang-Jun; Lee, Jeong-Ho; Kang, Dong-Gee

    2016-01-01

    Although the Codman-Hakim programmable valve is one of most popular shunt systems used in the clinical practice for the treatment of hydrocephalus, malfunctions related with this system have been also reported which lead to underdrainage or overdrainage of the cerebrospinal fluid. While obstruction of the ventricular catheter by tissue materials or hematoma and catheter disconnection are relatively common, the malfunction of the valve itself is rare. Herein, we report on a rare case of shunt overdrainage caused by displacement of the pressure control cam after pressure adjustment. A 57-year-old female, who underwent a ventriculoperitoneal shunt eight years ago, experienced aggravating symptoms of shunt overdrainage after pressure adjustment. Displacement of the pressure control cam was revealed on the X-ray, and a shunt revision was performed. The purpose of this report is to provide a working knowledge of the valve structure and to enhance the ability to interpret the valve setting on an X-ray for diagnosis of valve malfunction. PMID:27857929

  4. [Difficult Ventilation Requiring Emergency Endotracheal Intubation during Awake Craniotomy Managed by Laryngeal Mask Airway].

    PubMed

    Matsuda, Asako; Mizota, Toshiyuki; Tanaka, Tomoharu; Segawa, Hajime; Fukuda, Kazuhiko

    2016-04-01

    We report a case of difficult ventilation requiring emergency endotracheal intubation during awake craniotomy managed by laryngeal mask airway (LMA). A 45-year-old woman was scheduled to receive awake craniotomy for brain tumor in the frontal lobe. After anesthetic induction, airway was secured using ProSeal LMA and patient was mechanically ventilated in pressure-control mode. Patient's head was fixed with head-pins at anteflex position, and the operation started. About one hour after the start of the operation, tidal volume suddenly decreased. We immediately started manual ventilation, but the airway resistance was extremely high and we could not adequately ventilate the patient. We administered muscle relaxant for suspected laryngospasm, but ventilatory status did not improve; so we decided to conduct emergency endotracheal intubation. We tried to intubate using Airwayscope or LMA-Fastrach, but they were not effective in our case. Finally trachea was intubated using transnasal fiberoptic bronchoscopy. We discuss airway management during awake craniotomy, focusing on emergency endotracheal intubation during surgery.

  5. The School Advanced Ventilation Engineering Software (SAVES)

    EPA Pesticide Factsheets

    The School Advanced Ventilation Engineering Software (SAVES) package is a tool to help school designers assess the potential financial payback and indoor humidity control benefits of Energy Recovery Ventilation (ERV) systems for school applications.

  6. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTROL OF EXPLOSIVES AND OTHER HAZARDOUS MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. (1) All integral magazines shall be provided with natural or mechanical ventilation....

  7. Intraoperative mechanical ventilation for the pediatric patient.

    PubMed

    Kneyber, Martin C J

    2015-09-01

    Invasive mechanical ventilation is required when children undergo general anesthesia for any procedure. It is remarkable that one of the most practiced interventions such as pediatric mechanical ventilation is hardly supported by any scientific evidence but rather based on personal experience and data from adults, especially as ventilation itself is increasingly recognized as a harmful intervention that causes ventilator-induced lung injury. The use of low tidal volume and higher levels of positive end-expiratory pressure became an integral part of lung-protective ventilation following the outcomes of clinical trials in critically ill adults. This approach has been readily adopted in pediatric ventilation. However, a clear association between tidal volume and mortality has not been ascertained in pediatrics. In fact, experimental studies have suggested that young children might be less susceptible to ventilator-induced lung injury. As such, no recommendations on optimal lung-protective ventilation strategy in children with or without lung injury can be made.

  8. Intentional portal pressure control is key to improving the outcome of living donor liver transplantation: the Kyoto University Hospital experience.

    PubMed

    Ogura, Yasuhiro; Hori, Tomohide; Uemoto, Shinji

    2008-01-01

    This study indicates that intentional portal pressure control under 20 mmHg can improve patient survival not only for recipients of small-for-size grafts but also in classically appropriately sized grafts undergoing A-LDLT. In a retrospective analysis of 100 transplants with intentional portal pressure control, we found that patient survival was significantly better at an even lower final portal pressure of 15 mmHg. As a result, we have adjusted our target portal pressure control protocol, targeting a final portal pressure below 15 mmHg. Portal pressure control allows living donors to donate the smaller left lobe in many cases, which is safer in terms of living donors' post-operative morbidity. As intentional portal pressure control can overcome size-mismatching between the donor and recipient, we propose that it may also be applied to deceased donor liver grafts and in the split-liver transplant setting when the graft size is considered small for the recipient. Intentional portal pressure control can be applied in many liver transplantation situations to overcome small-for-size problems.

  9. 33 CFR 175.201 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Ventilation. 175.201 Section 175... SAFETY EQUIPMENT REQUIREMENTS Ventilation § 175.201 Ventilation. No person may operate a boat built after July 31, 1980, that has a gasoline engine for electrical generation, mechanical power, or...

  10. 9 CFR 91.21 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Ventilation. 91.21 Section 91.21... LIVESTOCK FOR EXPORTATION Inspection of Vessels and Accommodations § 91.21 Ventilation. Each underdeck... mechanical ventilation that will furnish a complete change of air in each compartment every 2 minutes...

  11. 14 CFR 125.117 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Ventilation. 125.117 Section 125.117 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS....117 Ventilation. Each passenger or crew compartment must be suitably ventilated. Carbon...

  12. 14 CFR 125.117 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Ventilation. 125.117 Section 125.117 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS....117 Ventilation. Each passenger or crew compartment must be suitably ventilated. Carbon...

  13. 9 CFR 91.21 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Ventilation. 91.21 Section 91.21... LIVESTOCK FOR EXPORTATION Inspection of Vessels and Accommodations § 91.21 Ventilation. Each underdeck... mechanical ventilation that will furnish a complete change of air in each compartment every 2 minutes...

  14. 9 CFR 91.21 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Ventilation. 91.21 Section 91.21... LIVESTOCK FOR EXPORTATION Inspection of Vessels and Accommodations § 91.21 Ventilation. Each underdeck... mechanical ventilation that will furnish a complete change of air in each compartment every 2 minutes...

  15. 14 CFR 125.117 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Ventilation. 125.117 Section 125.117 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS....117 Ventilation. Each passenger or crew compartment must be suitably ventilated. Carbon...

  16. 14 CFR 125.117 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Ventilation. 125.117 Section 125.117 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS....117 Ventilation. Each passenger or crew compartment must be suitably ventilated. Carbon...

  17. 14 CFR 29.831 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ventilation. 29.831 Section 29.831 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... Ventilation. (a) Each passenger and crew compartment must be ventilated, and each crew compartment must...

  18. High-Frequency Percussive Ventilation Revisited

    DTIC Science & Technology

    2010-01-01

    been associated with a decrease in the incidence of ventilator - associated pneumonia and an improvement in mortality among inhalational injury patients... ventilator - associ - ated pneumonia , or mortality. Although intriguing, these clinical reports are lim- ited by small sample sizes, retrospective...of HFPV theory toward improving gas exchange. Furthermore, no discussion has been held regarding the possible risk of HFPV- associated ventilator

  19. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... CONTROL OF EXPLOSIVES AND OTHER HAZARDOUS MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. (1) All integral magazines shall be provided with natural or mechanical ventilation. Design... 46 Shipping 7 2013-10-01 2013-10-01 false Ventilation. 194.10-25 Section 194.10-25 Shipping...

  20. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... as to provide the level and quality of ventilation specified and designed by the manufacturer for the... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Ventilation systems. 252.9 Section 252.9... REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking...

  1. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CONTROL OF EXPLOSIVES AND OTHER HAZARDOUS MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. (1) All integral magazines shall be provided with natural or mechanical ventilation. Design... 46 Shipping 7 2014-10-01 2014-10-01 false Ventilation. 194.10-25 Section 194.10-25 Shipping...

  2. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CONTROL OF EXPLOSIVES AND OTHER HAZARDOUS MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. (1) All integral magazines shall be provided with natural or mechanical ventilation. Design... 46 Shipping 7 2011-10-01 2011-10-01 false Ventilation. 194.10-25 Section 194.10-25 Shipping...

  3. 14 CFR 29.831 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Ventilation. 29.831 Section 29.831... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 29.831 Ventilation. (a) Each passenger and crew compartment must be ventilated, and each crew compartment must...

  4. 14 CFR 29.831 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Ventilation. 29.831 Section 29.831... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 29.831 Ventilation. (a) Each passenger and crew compartment must be ventilated, and each crew compartment must...

  5. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... as to provide the level and quality of ventilation specified and designed by the manufacturer for the... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Ventilation systems. 252.9 Section 252.9... REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking...

  6. 14 CFR 27.831 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 27.831 Ventilation. (a) The ventilating system for the pilot and passenger compartments must be designed to prevent... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Ventilation. 27.831 Section...

  7. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CONTROL OF EXPLOSIVES AND OTHER HAZARDOUS MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. (1) All integral magazines shall be provided with natural or mechanical ventilation. Design... 46 Shipping 7 2012-10-01 2012-10-01 false Ventilation. 194.10-25 Section 194.10-25 Shipping...

  8. 14 CFR 27.831 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 27.831 Ventilation. (a) The ventilating system for the pilot and passenger compartments must be designed to prevent... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ventilation. 27.831 Section...

  9. 14 CFR 29.831 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Ventilation. 29.831 Section 29.831... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 29.831 Ventilation. (a) Each passenger and crew compartment must be ventilated, and each crew compartment must...

  10. 14 CFR 29.831 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ventilation. 29.831 Section 29.831... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 29.831 Ventilation. (a) Each passenger and crew compartment must be ventilated, and each crew compartment must...

  11. 14 CFR 27.831 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 27.831 Ventilation. (a) The ventilating system for the pilot and passenger compartments must be designed to prevent... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ventilation. 27.831 Section...

  12. 14 CFR 27.831 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 27.831 Ventilation. (a) The ventilating system for the pilot and passenger compartments must be designed to prevent... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Ventilation. 27.831 Section...

  13. 46 CFR 194.15-5 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) Ventilation of air conditioning systems serving the chemical laboratory shall be designed so that air cannot... 46 Shipping 7 2012-10-01 2012-10-01 false Ventilation. 194.15-5 Section 194.15-5 Shipping COAST....15-5 Ventilation. (a) Operations, reactions or experiments which produce toxic, noxious or...

  14. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... as to provide the level and quality of ventilation specified and designed by the manufacturer for the... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Ventilation systems. 252.9 Section 252.9... REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking...

  15. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... as to provide the level and quality of ventilation specified and designed by the manufacturer for the... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Ventilation systems. 252.9 Section 252.9... REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking...

  16. 14 CFR 27.831 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 27.831 Ventilation. (a) The ventilating system for the pilot and passenger compartments must be designed to prevent... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Ventilation. 27.831 Section...

  17. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... as to provide the level and quality of ventilation specified and designed by the manufacturer for the... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Ventilation systems. 252.9 Section 252.9... REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking...

  18. 46 CFR 194.15-5 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Ventilation of air conditioning systems serving the chemical laboratory shall be designed so that air cannot... 46 Shipping 7 2011-10-01 2011-10-01 false Ventilation. 194.15-5 Section 194.15-5 Shipping COAST....15-5 Ventilation. (a) Operations, reactions or experiments which produce toxic, noxious or...

  19. 33 CFR 175.201 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Ventilation. 175.201 Section 175.201 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY EQUIPMENT REQUIREMENTS Ventilation § 175.201 Ventilation. No person may operate a boat built...

  20. 14 CFR 125.117 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Ventilation. 125.117 Section 125.117 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS....117 Ventilation. Each passenger or crew compartment must be suitably ventilated. Carbon...

  1. The effect of changing ventilator settings on indices of ventilation inhomogeneity in small ventilated lungs

    PubMed Central

    Schmalisch, G; Proquitté, H; Roehr, CC; Wauer, RR

    2006-01-01

    Background In ventilated newborns the use of multiple breath washout (MBW) techniques for measuring both lung volume and ventilation inhomogeneity (VI) is hampered by the comparatively high dead space fraction. We studied how changes in ventilator settings affected VI indices in this particular population. Methods Using a computer simulation of a uniformly ventilated volume the interaction between VI indices (lung clearance index (LCI), moment ratios (M1/M0, M2/M0, AMDN1, AMDN2) of the washout curve) and tidal volume (VT), dead space (VD) and functional residual capacity (FRC) were calculated. The theoretical results were compared with measurements in 15 ventilated piglets (age <12 h, median weight 1135 g) by increasing the peak inspiratory pressure (PIP). FRC and VI indices were measured by MBW using 0.8% heptafluoropropane as tracer gas. Results The computer simulation showed that the sensitivity of most VI indices to changes in VD/VT and VT/FRC increase, in particular for VD/VT > 0.5. In piglets, the raised PIP caused a significant increase of VT from 15.4 ± 9.5 to 21.9 ± 14.7 (p = 0.003) and of the FRC from 31.6 ± 14.7 mL to 35.0 ± 15.9 mL (p = 0.006), whereas LCI (9.15 ± 0.75 to 8.55 ± 0.74, p = 0.019) and the moment ratios M1/M0, M2/M0 (p < 0.02) decreased significantly. No significant changes were seen in AMDN1 and AMDN2. The within-subject variability of the VI indices (coefficient of variation in brackets) was distinctly higher (LCI (9.8%), M1/M0 (6.6%), M2/M0 (14.6%), AMDN1 (9.1%), AMDN2 (16.3%)) compared to FRC measurements (5.6%). Computer simulations showed that significant changes in VI indices were exclusively caused by changes in VT and FRC and not by an improvement of the homogeneity of alveolar ventilation. Conclusion In small ventilated lungs with a high dead space fraction, indices of VI may be misinterpreted if the changes in ventilator settings are not considered. Computer simulations can help to prevent this misinterpretation. PMID

  2. Preventing Ventilation On Sailboard Skegs

    NASA Technical Reports Server (NTRS)

    Caldwell, Richard A.

    1990-01-01

    Design effort undertaken to solve spinout problem plaguing high-performance sailboards. Proposed skeg section designed by use of computer model of pressure field and boundary layer. Prevents ventilation by maintaining attached boundary-layer flow throughout operating environment. Cavitation also avoided by preventing valleys in pressure distribution while skeg operated throughout its range.

  3. Fire Service Training. Ventilation. (Revised).

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Community Colleges, Raleigh.

    One of a set of fourteen outlines for use in a course to train novice firemen, this guide covers ventilation practices and principles. As background, subjects such as heat transmission and building construction are included. The three objectives of this part of the course are to enable the fireman to (1) rescue trapped victims, (2) locate fires as…

  4. Prognosis of mechanically ventilated patients.

    PubMed Central

    Papadakis, M A; Lee, K K; Browner, W S; Kent, D L; Matchar, D B; Kagawa, M K; Hallenbeck, J; Lee, D; Onishi, R; Charles, G

    1993-01-01

    In this Department of Veterans Affairs cooperative study, we examined predictors of in-hospital and 1-year mortality of 612 mechanically ventilated patients from 6 medical intensive care units in a retrospective cohort design. The outcome variable was vital status at hospital discharge and after 1 year. The results showed that 97% of patients were men, the mean age was 63 +/- 11 years (SD), and hospital mortality was 64% (95% confidence interval, 60% to 68%). Within the next year, an additional 38% of hospital survivors died, for a total 1-year mortality of 77% (95% confidence interval, 73% to 80%). Hospital and 1-year mortality, respectively, for patients older than 70 years was 76% and 94%, for those with serum albumin levels below 20 grams per liter it was 92% and 96%, for those with an Acute Physiology and Chronic Health Evaluation II (APACHE II) score greater than 35 it was 91% and 98%, and for patients who were being mechanically ventilated after cardiopulmonary resuscitation it was 86% and 90%. The mortality ratio (actual mortality versus APACHE II-predicted mortality) was 1.15. Conclusions are that patient age, APACHE II score, serum albumin levels, or the use of cardiopulmonary resuscitation may identify a subset of mechanically ventilated veterans for whom mechanical ventilation provides little or no benefit. PMID:8128673

  5. Population Structure of Streptococcus pneumoniae Causing Invasive Disease in Adults in Portugal before PCV13 Availability for Adults: 2008-2011

    PubMed Central

    Horácio, Andreia N.; Silva-Costa, Catarina; Diamantino-Miranda, Jorge; Lopes, Joana P.; Ramirez, Mario; Melo-Cristino, José

    2016-01-01

    Among the 1660 isolates recovered from invasive pneumococcal disease (IPD) in adults (> = 18 yrs) in 2008–2011, a random sample of ≥50% of each serotype (n = 871) was chosen for MLST analysis and evaluation for the presence and type of pilus islands (PIs). The genetic diversity was high with 206 different sequence types (STs) detected, but it varied significantly between serotypes. The different STs represented 80 clonal complexes (CCs) according to goeBURST with the six more frequent accounting for more than half (50.6%) of the isolates—CC156 (serotypes 14, 9V and 23F), CC191 (serotype 7F), CC180 (serotype 3), CC306 (serotype 1), CC62 (serotypes 8 and 11A) and CC230 (serotype 19A). Most of the isolates (n = 587, 67.3%) were related to 29 Pneumococcal Molecular Epidemiology Network recognized clones. The overall proportion of isolates positive for any of the PIs was small (31.9%) and declined gradually during the study period (26.6% in 2011), mostly due to the significant decline of serotype 1 which is associated with PI-2. The changes in serotypes that occurred in adult IPD after the introduction of the seven-valent pneumococcal conjugate vaccine (PCV7) for children were mostly due to the expansion of previously circulating clones, while capsular switching was infrequent and not related to vaccine use. The reduction of IPD caused by PCV7 serotypes in the years following PCV7 implementation did not result in a decline of antimicrobial resistance in part due to the selection of resistant genotypes among serotypes 14 and 19A. PMID:27168156

  6. Unusual outcome of in utero infection and subsequent postnatal super-infection with different PCV2b strains.

    PubMed

    Saha, Dipongkor; Karniychuk, Uladzimir U; Huang, Liping; Geldhof, Marc; Vanhee, Merijn; Lefebvre, David J; Meerts, Peter; Ducatelle, Richard; Doorsselaere, Jan V; Nauwynck, Hans J

    2014-06-01

    VC2002, isolated from postweaning multisystemic wasting syndrome (PMWS)-affected pig, is a mixture of two porcine circovirus genotype 2b (PCV2b) viruses, K2 and K39. Preliminary experiments disclosed short-term adverse effects of K39, but not K2, on porcine foetuses. These findings led to the hypothesis that infection of immuno-incompetent foetuses with K2 confers a status of immunotolerance, and postnatal super-infection with K39 triggers PMWS. To explore this hypothesis, nine 55-day-old foetuses were inoculated in utero (three with K2-10(4.3)TCID50, three with K39-10(4.3)TCID50 and three with medium), and foeto-pathogenicity examined. At 21 days post-inoculation (dpi), K2 did not induce pathology, whereas pathological effects of K39 were evident. Twenty-four 45-day-old foetuses were subsequently inoculated to examine the long-term effect of K2, including six with K2-high dose-10(4.3)TCID50, six with K2-low dose-10(2.3)TCID50 and 12 mock-inoculated controls. Both doses resulted in five mummified foetuses and one live-born piglet each (69dpi). K2 was recovered from all mummies. K2 and K2-specific antibodies were not detected in serum of the two live-born piglets at birth, indicating full control of K2 infection. The K2-low dose-infected piglet was immunostimulated at day 2, but not the K2-high dose-infected piglet. Both non-stimulated and stimulated K2-infected piglets were super-inoculated with K39 at day 6 or 8 (taken as 0 days post super-inoculation). Low viral replication was observed in the non-stimulated K2-K39 piglet (up to 10(3.3)TCID50/g; identified as K39). In contrast, viral replication was extremely high in the stimulated K2-K39 piglet (up to 10(5.6)TCID50/g) and identified as K2, indicating that K2 infection is controlled during foetal life, but emerges after birth upon immunostimulation. However, none of the piglets showed any signs of PMWS.

  7. A comparison of fuzzy logic-PID control strategies for PWR pressurizer control

    SciTech Connect

    Kavaklioglu, K.; Ikonomopoulos, A. )

    1993-01-01

    This paper describes the results obtained from a comparison performed between classical proportional-integral-derivative (PID) and fuzzy logic (FL) controlling the pressure in a pressurized water reactor (PWR). The two methodologies have been tested under various transient scenarios, and their performances are evaluated with respect to robustness and on-time response to external stimuli. One of the main concerns in the safe operation of PWR is the pressure control in the primary side of the system. In order to maintain the pressure in a PWR at the desired level, the pressurizer component equipped with sprayers, heaters, and safety relief valves is used. The control strategy in a Westinghouse PWR is implemented with a PID controller that initiates either the electric heaters or the sprayers, depending on the direction of the coolant pressure deviation from the setpoint.

  8. Independent Orbiter Assessment (IOA): Assessment of the atmospheric revitalization pressure control subsystem FMEA/CIL

    NASA Technical Reports Server (NTRS)

    Saiidi, M. J.

    1988-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the atmospheric Revitalization Pressure Control Subsystem (ARPCS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL proposed Post 51-L updates based upon the CCB/PRCB presentations and an informal criticality summary listing. A discussion of each discrepancy from the comparison is provided through additional analysis as required. These discrepancies were flagged as issues, and recommendations were made based on the FMEA data available at the time. This report documents the results of that comparison for the Orbiter ARPCS hardware.

  9. Development of an expert system for analysis of Shuttle atmospheric revitalization and pressure control subsystem anomalies

    NASA Technical Reports Server (NTRS)

    Lafuse, Sharon A.

    1991-01-01

    The paper describes the Shuttle Leak Management Expert System (SLMES), a preprototype expert system developed to enable the ECLSS subsystem manager to analyze subsystem anomalies and to formulate flight procedures based on flight data. The SLMES combines the rule-based expert system technology with the traditional FORTRAN-based software into an integrated system. SLMES analyzes the data using rules, and, when it detects a problem that requires simulation, it sets up the input for the FORTRAN-based simulation program ARPCS2AT2, which predicts the cabin total pressure and composition as a function of time. The program simulates the pressure control system, the crew oxygen masks, the airlock repress/depress valves, and the leakage. When the simulation has completed, other SLMES rules are triggered to examine the results of simulation contrary to flight data and to suggest methods for correcting the problem. Results are then presented in form of graphs and tables.

  10. The effect of tiaprofenic acid on blood pressure control in treated hypertensive patients.

    PubMed

    Smith, M D; Kupa, A; Weatherall, M; Henstridge, J D; Brooks, P M

    1985-01-01

    Eleven patients with osteoarthritis and mild hypertension completed an 8-week, double-blind crossover study in which 200 mg tiaprofenic acid 3-times daily or placebo were substituted for their normal non-steroidal anti-inflammatory therapy. Systolic blood pressure was significantly higher on tiaprofenic acid therapy than on placebo and plasma renin activity was significantly lower on active treatment. No significant changes were seen in biochemical parameters, though the weight of the patient was also higher on tiaprofenic acid than on placebo. Duration of morning stiffness was also lower on tiaprofenic acid than on placebo. Blood pressure on tiaprofenic acid was not different from baseline readings on other non-steroidal anti-inflammatory drug therapy. This study suggests that tiaprofenic acid, like other non-steroidal anti-inflammatory agents, may interfere with blood pressure control in treated hypertensive patients.

  11. Economics of mechanical ventilation and respiratory failure.

    PubMed

    Cooke, Colin R

    2012-01-01

    For patients with acute respiratory failure, mechanical ventilation provides the most definitive life-sustaining therapy. Because of the intense resources required to care for these patients, its use accounts for considerable costs. There is great societal need to ensure that use of mechanical ventilation maximizes societal benefits while minimizing costs, and that mechanical ventilation, and ventilator support in general, is delivered in the most efficient and cost-effective manner. This review summarizes the economic aspects of mechanical ventilation and summarizes the existing literature that examines its economic impact cost effectiveness.

  12. Efficient atraumatic liquid suction by means of slit suction tubes combined with a pressure control unit.

    PubMed

    Vällfors, B

    1984-01-01

    In 1976 a modified suction system for neurosurgery and precision surgery was presented. It was developed to meet the need for efficient and atraumatic liquid suction. the system consists of suction tube ends provided with three vertical slits in the suction edge (W-tubes), a Pressure Control Unit (PCU) and an independent suction pump with an air capacity of 25-30 litres per min. This system has subsequently been modified for microsurgery. The PCU normally controls the negative pressure to 20 kPa (corresponding to 200 cm of water) for atraumatic suction of liquid, which is needed during most of the operating time. For suction of various tissues or cleaning the system, the surgeon can set the pressure limit to 50 or 90 kPa by means of a foot-operated IR-transmitter in a pedal with a kick-down function. The PCU and the W-tubes, which neutralize the pressure load on tissue and the sudden interruption of liquid flow that are inevitable with conventional suction tips, form a system with a high liquid suction capacity in spite of the atraumatic suction pressure. This is possible because the slits maintain a large active suction area. Crushed or soft tissues and coagulated blood are aspirated as and when required, if necessary by elevation of the negative pressure limit. The W-tubes are not provided with an air inlet hole on the tube because that method of pressure control proved unpredictable and variable and reduced the suction capacity by interfering with the flow.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Tank Pressure Control Experiment: Thermal Phenomena in Microgravity. Video 4 of 4

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The report presents the results of the flight experiment Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP) performed in the microgravity environment of the space shuttle. TPCE/TP, flown on the Space Transportation System STS-52, was a second flight of the Tank Pressure Control Experiment (TPCE). The experiment used Freon 113 at near saturation conditions. The test tank was filled with liquid to about 83 percent by volume. The experiment consisted of 21 tests. Each test generally started with a heating phase to increase the tank pressure and to develop temperature stratification in the fluid, followed by a fluid mixing phase for the tank pressure reduction and fluid temperature equilibration. The heating phase provided pool boiling data from large (relative to bubble sizes) heating surfaces (0.1046 m by 0.0742 m) at low heat fluxes (0.23 to 1.16 kW/m(exp 2)). The system pressure and the bulk liquid subcooling varied from 39 to 78 kPa and 1 to 3 deg C, respectively. The boiling process during the entire heating period, as well a jet-induced mixing process for the first 2 min. of the mixing period, was also recorded on video. Analyses of data from the two flight experiments (TPCE and TPCE/TP) and their comparison with the results obtained in drop tower experiments suggest that as Bond number approaches zero the flow pattern produced by an axial jet and the mixing time can be predicted by the Weber number. This is video 4 of 4.

  14. Tank Pressure Control Experiment: Thermal Phenomena in Microgravity. Video 2 of 4

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The report presents the results of the flight experiment Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP) performed in the microgravity environment of the space shuttle. TPCE/TP, flown on the Space Transportation System STS-52, was a second flight of the Tank Pressure Control Experiment (TPCE). The experiment used Freon 113 at near saturation conditions. The test tank was filled with liquid to about 83 percent by volume. The experiment consisted of 21 tests. Each test generally started with a heating phase to increase the tank pressure and to develop temperature stratification in the fluid, followed by a fluid mixing phase for the tank pressure reduction and fluid temperature equilibration. The heating phase provided pool boiling data from large (relative to bubble sizes) heating surfaces (0.1046 m by 0.0742 m) at low heat fluxes (0.23 to 1.16 kW/m(exp 2)). The system pressure and the bulk liquid subcooling varied from 39 to 78 kPa and 1 to 3 deg C, respectively. The boiling process during the entire heating period, as well a jet-induced mixing process for the first 2 min. of the mixing period, was also recorded on video. Analyses of data from the two flight experiments (TPCE and TPCE/TP) and their comparison with the results obtained in drop tower experiments suggest that as Bond number approaches zero the flow pattern produced by an axial jet and the mixing time can be predicted by the Weber number. This is video 2 of 4.

  15. Tank Pressure Control Experiment: Thermal Phenomena in Microgravity. Video 1 of 4

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The report presents the results of the flight experiment Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP) performed in the microgravity environment of the space shuttle. TPCE/TP, flown on the Space Transportation System STS-52, was a second flight of the Tank Pressure Control Experiment (TPCE). The experiment used Freon 113 at near saturation conditions. The test tank was filled with liquid to about 83 percent by volume. The experiment consisted of 21 tests. Each test generally started with a heating phase to increase the tank pressure and to develop temperature stratification in the fluid, followed by a fluid mixing phase for the tank pressure reduction and fluid temperature equilibration. The heating phase provided pool boiling data from large (relative to bubble sizes) heating surfaces (0.1046 m by 0.0742 m) at low heat fluxes (0.23 to 1.16 kW/m(exp 2)). The system pressure and the bulk liquid subcooling varied from 39 to 78 kPa and 1 to 3 deg C, respectively. The boiling process during the entire heating period, as well a jet-induced mixing process for the first 2 min. of the mixing period, was also recorded on video. Analyses of data from the two flight experiments (TPCE and TPCE/TP) and their comparison with the results obtained in drop tower experiments suggest that as Bond number approaches zero the flow pattern produced by an axial jet and the mixing time can be predicted by the Weber number. This is video 1 of 4.

  16. Tank Pressure Control Experiment: Thermal Phenomena in Microgravity. Video 3 of 4

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The report presents the results of the flight experiment Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP) performed in the microgravity environment of the space shuttle. TPCE/TP, flown on the Space Transportation System STS-52, was a second flight of the Tank Pressure Control Experiment (TPCE). The experiment used Freon 113 at near saturation conditions. The test tank was filled with liquid to about 83 percent by volume. The experiment consisted of 21 tests. Each test generally started with a heating phase to increase the tank pressure and to develop temperature stratification in the fluid, followed by a fluid mixing phase for the tank pressure reduction and fluid temperature equilibration. The heating phase provided pool boiling data from large (relative to bubble sizes) heating surfaces (0.1046 m by 0.0742 m) at low heat fluxes (0.23 to 1.16 kW/m(exp 2)). The system pressure and the bulk liquid subcooling varied from 39 to 78 kPa and 1 to 3 deg C, respectively. The boiling process during the entire heating period, as well a jet-induced mixing process for the first 2 min. of the mixing period, was also recorded on video. Analyses of data from the two flight experiments (TPCE and TPCE/TP) and their comparison with the results obtained in drop tower experiments suggest that as Bond number approaches zero the flow pattern produced by an axial jet and the mixing time can be predicted by the Weber number. This is video 3 of 4.

  17. Factors associated with blood pressure control amongst adults with hypertension in Yaounde, Cameroon: a cross-sectional study

    PubMed Central

    Menanga, Alain; Edie, Sandrine; Boombhi, Jérôme; Musa, Ahmadou Jingi; Mfeukeu, Liliane Kuate; Kingue, Samuel

    2016-01-01

    Background Hypertension is associated with considerable morbidity and mortality. Improvement of its management to reduce adverse cardiovascular outcomes will require an understanding of the patient characteristics and treatment factors associated with uncontrolled blood pressure. Factors that affect blood pressure control have not been sufficiently described in Cameroon. The main goal of our study was to determine the predictors of blood pressure control in patients with hypertension in an urban city in Cameroon. Methods This was descriptive cross-sectional study from five outpatient hypertension consultation units in Hospitals in Yaoundé. Controlled hypertension was defined as blood pressure ≤140/90 mmHg. Logistic regression was used to determine factors associated with blood pressure control. Results Among the 440 patients enrolled in the survey, 280 (63.6%) were females. The mean age was 61 (SD ±11) years. Mean systolic blood pressure (SBP) was 147 mmHg and mean diastolic blood pressure (DBP) was 88 mmHg. Only 36.8% of patients had their mean blood pressure controlled (BP ≤140/90 mmHg). Multivariable logistic regression analysis revealed good adherence to anti-hypertensive medications (OR= 3.99; 95% CI: 2.20–7.23; P<0.000) and dietary lifestyle changes (OR =1.5; 95% CI: 0.53–2.49; P=0.031) to be factors independently associated with controlled hypertension. Conclusions Only one out of three patients has their blood pressure controlled. The results of our study suggest that good adherence to treatment are important factors for tight blood pressure control in primary care. Further identification of patients at risk of non-adherence to treatment and poor blood pressure control can lead to targeted interventions to reduce hypertension related morbidity and mortality in this setting. PMID:27747167

  18. Night ventilation control strategies in office buildings

    SciTech Connect

    Wang, Zhaojun; Yi, Lingli; Gao, Fusheng

    2009-10-15

    In moderate climates night ventilation is an effective and energy-efficient approach to improve the indoor thermal environment for office buildings during the summer months, especially for heavyweight construction. However, is night ventilation a suitable strategy for office buildings with lightweight construction located in cold climates? In order to answer this question, the whole energy-consumption analysis software EnergyPlus was used to simulate the indoor thermal environment and energy consumption in typical office buildings with night mechanical ventilation in three cities in northern China. The summer outdoor climate data was analyzed, and three typical design days were chosen. The most important factors influencing night ventilation performance such as ventilation rates, ventilation duration, building mass and climatic conditions were evaluated. When night ventilation operation time is closer to active cooling time, the efficiency of night ventilation is higher. With night ventilation rate of 10 ach, the mean radiant temperature of the indoor surface decreased by up to 3.9 C. The longer the duration of operation, the more efficient the night ventilation strategy becomes. The control strategies for three locations are given in the paper. Based on the optimized strategies, the operation consumption and fees are calculated. The results show that more energy is saved in office buildings cooled by a night ventilation system in northern China than ones that do not employ this strategy. (author)

  19. Summary of human responses to ventilation

    SciTech Connect

    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

  20. Effect of Residual Noncondensables on Pressurization and Pressure Control of a Zero-Boil-Off Tank in Microgravity

    NASA Technical Reports Server (NTRS)

    Kassemi, Mohammad; Hylton, Sonya; Kartizova, Olga

    2013-01-01

    The Zero-Boil-Off Tank (ZBOT) Experiment is a small-scale experiment that uses a transparent ventless Dewar and a transparent simulant phase-change fluid to study sealed tank pressurization and pressure control with applications to on-surface and in-orbit storage of propellant cryogens. The experiment will be carried out under microgravity conditions aboard the International Space Station in the 2014 timeframe. This paper presents preliminary results from ZBOT's ground-based research that focuses on the effects of residual noncondensable gases in the ullage on both pressurization and pressure reduction trends in the sealed Dewar. Tank pressurization is accomplished through heating of the test cell wall in the wetted and un-wetted regions simultaneously or separately. Pressure control is established through mixing and destratification of the bulk liquid using a temperature controlled forced jet flow with different degrees of liquid jet subcooling. A Two-Dimensional axisymmetric two-phase CFD model for tank pressurization and pressure control is also presented. Numerical prediction of the model are compared to experimental 1g results to both validate the model and also indicate the effect of the noncondensable gas on evolution of pressure and temperature distributions in the ullage during pressurization and pressure control. Microgravity simulations case studies are also performed using the validated model to underscore and delineate the profound effect of the noncondensables on condensation rates and interfacial temperature distributions with serious implications for tank pressure control in reduced gravity.

  1. [Impact of PCV10 pneumococcal vaccine on mortality from pneumonia in children less than one year of age in Santa Catarina State, Brazil].

    PubMed

    Kupek, Emil; Vieira, Ilse Lisiane Viertel

    2016-03-01

    The aim of this study was to evaluate the impact of PCV10 pneumococcal vaccine on mortality from pneumonia in children less than one year of age in Santa Catarina State, Brazil, comparing the four years prior and the four years subsequent to the vaccine's introduction in 2010. This ecological study used data from the Mortality Information System and vaccination coverage of children less than one year. Data were grouped by municipalities of residence and regions. Average mortality from pneumonia in children under one year decreased from 29.69 to 23.40 per 100,000, comparing 2006-2009 and 2010-2013, or a reduction of 11%. However there were differences between regions with a drop in mortality (Grande Florianópolis, Sul, Planalto Norte, and Nordeste) and others with an increase in the annual rates (Oeste, Itajaí, and Serra). In short, the state as a whole showed 11% reduction in mortality from pneumonia in children less than one year of age, four years after implementing routine PCV10 vaccination in the National Immunization Program, but with heterogeneous effects when comparing regions of the state.

  2. Prevention of ventilator-associated pneumonia.

    PubMed

    Lau, Arthur C W; So, H M; Tang, S L; Yeung, Alwin; Lam, S M; Yan, W W

    2015-02-01

    Ventilator-associated pneumonia is the commonest, yet mostly preventable, infection in mechanically ventilated patients. Successful control of ventilator-associated pneumonia can save hospitalisation cost, and is possible by using a multidisciplinary clinical and administrative approach. The ventilator-associated pneumonia rate should be expressed as the number of ventilator-associated pneumonia days per 1000 ventilator days to take into account the device-utilisation duration for meaningful comparison. Various strategies address the issue, including general infection control measures, body positioning, intubation and mechanical ventilation, oral and gastro-intestinal tract, endotracheal tube, airway pressure, cuff pressure, selective digestive and/or oropharyngeal decontamination, and probiotic or early antibiotic treatment, as well as overall administration at a policy level. The rationale and controversy of these approaches are discussed in this article. The authors suggest that all units treating mechanically ventilated patients should have a ventilator-associated pneumonia prevention protocol in place, and ventilator-associated pneumonia should be seriously considered as a key performance indicator in local intensive care units.

  3. Development of a Residential Integrated Ventilation Controller

    SciTech Connect

    Staff Scientist; Walker, Iain; Sherman, Max; Dickerhoff, Darryl

    2011-12-01

    The goal of this study was to develop a Residential Integrated Ventilation Controller (RIVEC) to reduce the energy impact of required mechanical ventilation by 20percent, maintain or improve indoor air quality and provide demand response benefits. This represents potential energy savings of about 140 GWh of electricity and 83 million therms of natural gas as well as proportional peak savings in California. The RIVEC controller is intended to meet the 2008 Title 24 requirements for residential ventilation as well as taking into account the issues of outdoor conditions, other ventilation devices (including economizers), peak demand concerns and occupant preferences. The controller is designed to manage all the residential ventilation systems that are currently available. A key innovation in this controller is the ability to implement the concept of efficacy and intermittent ventilation which allows time shifting of ventilation. Using this approach ventilation can be shifted away from times of high cost or high outdoor pollution towards times when it is cheaper and more effective. Simulations, based on the ones used to develop the new residential ventilation requirements for the California Buildings Energy code, were used to further define the specific criteria and strategies needed for the controller. These simulations provide estimates of the energy, peak power and contaminant improvement possible for different California climates for the various ventilation systems. Results from a field test of the prototype controller corroborate the predicted performance.

  4. [Practices and effects of different measures for blood pressure control in hypertension patients in Beijing, 2014].

    PubMed

    Li, H; Dong, Z; Ma, A J; Dong, J; Fang, K; Xie, C; Qi, K; Xie, J; Zhou, Y; Zhao, Y

    2016-09-10

    Objective: To understand the practices and effects of different measures for blood pressure control in hypertension patients. Methods: Patients who have known hypertension from the subjects of "2014 Beijing adult (aged 18-79 years) chronic diseases and risk factors survey" were selected. The choices of different hypertension control measures, the relationship between the measures and demographic characteristics of hypertension patients, and the effects of different control measures were analyzed. Results: A total of 2 229 known hypertension patients were included, the analysis was conducted through a questionnaire survey. Those who answered "never taking any measures" , "taking medication according to doctor's instructions" and "taking medication when blood pressure rose" accounted for 7.0%, 79.8% and 8.3%, respectively. Those who had "diet control" , "physical exercises" and "blood pressure monitoring" accounted for 22.4%, 23.7% and 22.1%, respectively. In terms of "taking medicine according to doctor's instructions" , women (84.3%), those aged ≥60 years (87.6%), those living in urban area (81.5%), those living alone (83.8%), and Beijing local residents (82.3%) had higher compliance rates. As for "diet control" , women (24.4%), those aged ≥60 years (25.8%) and those with educational level of college or above (29.5%) had better practices. In terms of "physical exercise" , those aged ≥60 years (27.9%), those living in urban area (25.3%), those with educational level of college or above (32.5%) had better practice. Women (24.2%) and those aged ≥60 years (28.4%) had higher "blood pressure monitoring" rate. More men (9.7%), those aged 18-44 years (14.7%), those with educational level of high school (9.3%), the unmarried (18.2%), and non-Beijing local residents (14.7%) answered "never taking any measure" , and in terms of "taking medication when blood pressure rose" , non-Beijing local residents (12.8%) had higher rate. In the field survey, more patients who

  5. Particle deposition in ventilation ducts

    SciTech Connect

    Sippola, Mark Raymond

    2002-09-01

    Exposure to airborne particles is detrimental to human health and indoor exposures dominate total exposures for most people. The accidental or intentional release of aerosolized chemical and biological agents within or near a building can lead to exposures of building occupants to hazardous agents and costly building remediation. Particle deposition in heating, ventilation and air-conditioning (HVAC) systems may significantly influence exposures to particles indoors, diminish HVAC performance and lead to secondary pollutant release within buildings. This dissertation advances the understanding of particle behavior in HVAC systems and the fates of indoor particles by means of experiments and modeling. Laboratory experiments were conducted to quantify particle deposition rates in horizontal ventilation ducts using real HVAC materials. Particle deposition experiments were conducted in steel and internally insulated ducts at air speeds typically found in ventilation ducts, 2-9 m/s. Behaviors of monodisperse particles with diameters in the size range 1-16 μm were investigated. Deposition rates were measured in straight ducts with a fully developed turbulent flow profile, straight ducts with a developing turbulent flow profile, in duct bends and at S-connector pieces located at duct junctions. In straight ducts with fully developed turbulence, experiments showed deposition rates to be highest at duct floors, intermediate at duct walls, and lowest at duct ceilings. Deposition rates to a given surface increased with an increase in particle size or air speed. Deposition was much higher in internally insulated ducts than in uninsulated steel ducts. In most cases, deposition in straight ducts with developing turbulence, in duct bends and at S-connectors at duct junctions was higher than in straight ducts with fully developed turbulence. Measured deposition rates were generally higher than predicted by published models. A model incorporating empirical equations based on the

  6. Pharmacological Interactions on Blood Pressure Control in Arterial Hypertension, An Issue not to be Overlooked.

    PubMed

    Ciulla, Michele M; Benfenati, Chiara; Gallazzi, Enrico; Vivona, Patizia; Meazza, Roberto; Lombardi, Federico

    2016-01-01

    Our vision of long-term treatment strategies for the prevention of target organ damage and eventually cardiovascular morbidity and mortality in essential arterial hypertension needs to be continually monitored and updated for at least three issues: 1--the achievement of target pressure required to obtain the expected benefit needs continuous monitoring, a dose adjustment of the drug and, often, the use of combination therapies; 2--the chronic use of certain drugs, even in combination, is associated with the possible onset of side effects; 3--increasing of population life expectancy is inevitably associated with in an increase in drugs use with the unavoidable occurrence of adverse drug reactions, some of which can interfere with blood pressure control. These issues, still poorly studied, pose considerable problems in applying proper strategies for prevention. In this review, we will evaluate the goals of antihypertensive therapy, and its weak spots, such as the frequent side effects, that lead to poor therapy compliance. Moreover, we will review the interactions between antihypertensive and drugs used for other common disease, and their importance in not achieving the expected blood pressure reduction.

  7. Independent Orbiter Assessment (IOA): Analysis of the atmospheric revitalization pressure control subsystem

    NASA Technical Reports Server (NTRS)

    Saiidi, M. J.; Duffy, R. E.; Mclaughlin, T. D.

    1986-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis/Critical Items List (FMEA/CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The independent analysis results corresponding to the Orbiter Atmospheric Revitalization and Pressure Control Subsystem (ARPCS) are documented. The ARPCS hardware was categorized into the following subdivisions: (1) Atmospheric Make-up and Control (including the Auxiliary Oxygen Assembly, Oxygen Assembly, and Nitrogen Assembly); and (2) Atmospheric Vent and Control (including the Positive Relief Vent Assembly, Negative Relief Vent Assembly, and Cabin Vent Assembly). The IOA analysis process utilized available ARPCS hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.

  8. Multi-bottle, no compressor, mean pressure control system for a Stirling engine

    DOEpatents

    Corey, John A.

    1990-01-01

    The invention relates to an apparatus for mean pressure control of a Stirling engine without the need for a compressor. The invention includes a multi-tank system in which there is at least one high pressure level tank and one low pressure level tank wherein gas flows through a maximum pressure and supply line from the engine to the high pressure tank when a first valve is opened until the maximum pressure of the engine drops below that of the high pressure tank opening an inlet regulator to permit gas flow from the engine to the low pressure tank. When gas flows toward the engine it flows through the minimum pressure supply line 2 when a second valve is opened from the low pressure tank until the tank reaches the engine's minimum pressure level at which time the outlet regulator opens permitting gas to be supplied from the high pressure tank to the engine. Check valves between the two tanks prevent any backflow of gas from occurring.

  9. Compliance with the Prescription of Antihypertensive Medications and Blood Pressure Control in Primary Care

    PubMed Central

    Novello, Mayra Faria; Rosa, Maria Luiza Garcia; Ferreira, Ranier Tagarro; Nunes, Icaro Gusmão; Jorge, Antonio José Lagoeiro; Correia, Dayse Mary da Silva; Martins, Wolney de Andrade; Mesquita, Evandro Tinoco

    2017-01-01

    Background Hypertension is the most prevalent risk factor for cardiovascular disease, and its proper control can prevent the high morbidity and mortality associated with this disease. Objective To assess the degree of compliance of antihypertensive prescriptions with the VI Brazilian Guidelines on Hypertension and the blood pressure control rate in primary care. Methods Cross-sectional study conducted between August 2011 and November 2012, including 332 adults ≥ 45 years registered in the Family Doctor Program in Niteroi and selected randomly. The analysis included the prescribed antihypertensive classes, doses, and frequencies, as well as the blood pressure (BP) of the individuals. Results The rate of prescription compliance was 80%. Diuretics were the most prescribed medications, and dual therapy was the most used treatment. The most common non-compliances were underdosing and underfrequencies. The BP goal in all cases was < 140/90 mmHg, except for diabetic patients, in whom the goal was set at < 130/80 mmHg. Control rates according to these goals were 44.9% and 38.6%, respectively. There was no correlation between prescription compliance and BP control. Conclusions The degree of compliance was considered satisfactory. The achievement of the targets was consistent with national and international studies, suggesting that the family health model is effective in BP management, although it still needs improvement. PMID:28327875

  10. Heart rate and blood pressure control in obesity - how to detect early dysregulation?

    PubMed

    Javorka, Michal; Turianikova, Zuzana; Tonhajzerova, Ingrid; Lazarova, Zuzana; Czippelova, Barbora; Javorka, Kamil

    2016-09-01

    Obesity is accompanied by many severe complications including various cardiovascular disorders. An impairment of cardiovascular control by autonomic nervous system could be one of the possible links between obesity and cardiovascular complications development. The aim of this study was to compare spontaneous heart rate and systolic blood pressure oscillations reflecting cardiovascular autonomic control of young obese subjects with normal control subjects by linear and nonlinear methods and to find sensitive markers of early autonomic dysregulation. Continuous recordings of beat-to-beat systolic blood pressure and RR intervals from ECG were obtained from 40 obese subjects (25 female, age 14·2 [13·1-16·1] (median [interquartile range]) years) and gender and age matched non-obese control subjects. In addition to linear measures (time and frequency domain), we performed recurrence quantification analysis (RQA) and multiscale entropy analysis for both signals. While no significant differences in heart rate and systolic blood pressure dynamics were detected by linear measures and MSE, analysis of recurrence plots from RR intervals time series showed significant differences - indices trapping time and maximal length of vertical from RQA were significantly higher in obese compared to control group. We conclude that heart rate and blood pressure control by autonomic nervous system in young obese subjects is relatively well preserved. However, novel RQA-related measures are able to detect early subtle abnormalities in cardiac autonomic control in obese subjects indicating decreased signal complexity.

  11. Ventless pressure control of two-phase propellant tanks in microgravity

    NASA Technical Reports Server (NTRS)

    Kassemi, Mohammad; Panzarella, Charles H.

    2004-01-01

    This work studies pressurization and pressure control of a large liquid hydrogen storage tank. A finite element model is developed that couples a lumped thermodynamic formulation for the vapor region with a complete solution of the Navier-Stokes and energy equations for the flow and temperature fields in the liquid. Numerical results show that buoyancy effects are strong, even in microgravity, and can reposition a vapor bubble that is initially at the center of the tank to a region near the tank wall in a relatively short time. Long-term tank pressurization with the vapor bubble at the tank wall shows that after an initial transient lasting about a week, the final rate of pressure increase agrees with a purely thermodynamic analysis of the entire tank. However, the final pressure levels are quite different from thermodynamic predictions. Numerical results also show that there is significant thermal stratification in the liquid due to the effects of natural convection. A subcooled jet is used to provide simultaneous cooling and mixing in order to bring the tank pressure back down to its initial value. Three different jet speeds are examined. Although the lowest jet speed is ineffective at controlling the pressure because of insufficient penetration into the liquid region, the highest jet speed is shown to be quite effective at disrupting thermal stratification and reducing the tank pressure in reasonable time.

  12. Managing blood pressure control in Asian patients: safety and efficacy of losartan.

    PubMed

    Cheung, Tommy Tsang; Cheung, Bernard Man Yung

    2014-01-01

    Hypertension is common in Asian populations and is a major cause of cardiovascular diseases. The prevalence of hypertension is increasing in many Asian countries. The overall prevalence of hypertension in India and the People's Republic of China has been estimated to be 20.6% in men and 22.6% in women. However, the rates of detection, treatment, and control of hypertension remain low in Asia. This reflects a low level of literacy and education, as well as a low level of access to medical care. To overcome these obstacles, strategies targeted at education, promotion, and optimization of medical care, are crucial to achieve target blood pressure control. Angiotensin receptor blockers are one of the first-line treatments for essential hypertension because they confer better cardiovascular outcomes. Losartan has been widely evaluated for the management of hypertension. Although some studies suggested that the blood pressure-lowering effect of losartan is perhaps lower than for other angiotensin receptor blockers, losartan has been demonstrated to be beneficial in terms of renal protection in patients with diabetes, heart failure resulting from either systolic or diastolic dysfunction, and diuretic-induced hyperuricemia. However, most of these data were obtained from Caucasian populations. The efficacy and safety of losartan in Asian populations may be different because of genetic and ethnic variations. Therefore, the efficacy and safety of losartan in Asian patients with hypertension warrant further study.

  13. 30 CFR 57.8532 - Opening and closing ventilation doors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Opening and closing ventilation doors. 57.8532... Ventilation Underground Only § 57.8532 Opening and closing ventilation doors. When ventilation control doors...-establish normal ventilation to working places....

  14. 30 CFR 57.8532 - Opening and closing ventilation doors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Opening and closing ventilation doors. 57.8532... Ventilation Underground Only § 57.8532 Opening and closing ventilation doors. When ventilation control doors...-establish normal ventilation to working places....

  15. 30 CFR 57.8532 - Opening and closing ventilation doors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Opening and closing ventilation doors. 57.8532... Ventilation Underground Only § 57.8532 Opening and closing ventilation doors. When ventilation control doors...-establish normal ventilation to working places....

  16. 30 CFR 75.330 - Face ventilation control devices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Face ventilation control devices. 75.330... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.330 Face ventilation control devices. (a) Brattice cloth, ventilation tubing and other face ventilation control devices...

  17. 30 CFR 75.330 - Face ventilation control devices.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Face ventilation control devices. 75.330... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.330 Face ventilation control devices. (a) Brattice cloth, ventilation tubing and other face ventilation control devices...

  18. 30 CFR 75.330 - Face ventilation control devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Face ventilation control devices. 75.330... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.330 Face ventilation control devices. (a) Brattice cloth, ventilation tubing and other face ventilation control devices...

  19. 30 CFR 75.330 - Face ventilation control devices.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Face ventilation control devices. 75.330... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.330 Face ventilation control devices. (a) Brattice cloth, ventilation tubing and other face ventilation control devices...

  20. 30 CFR 75.330 - Face ventilation control devices.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Face ventilation control devices. 75.330... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.330 Face ventilation control devices. (a) Brattice cloth, ventilation tubing and other face ventilation control devices...

  1. [Home mechanical ventilation: Invasive and noninvasive ventilation therapy for chronic respiratory failure].

    PubMed

    Huttmann, S E; Storre, J H; Windisch, W

    2015-06-01

    Home mechanical ventilation represents a valuable therapeutic option to improve alveolar ventilation in patients with chronic respiratory failure. For this purpose both invasive ventilation via tracheostomy and noninvasive ventilation via facemasks are available. The primary goal of home mechanical ventilation is a reduction of symptoms, improvement of quality of life and in many cases reduction of mortality. Elective establishment of home mechanical ventilation is typically provided for noninvasive ventilation in respect to clinical symptoms and partial pressure of carbon dioxide depending on the underlying disease. However, invasive mechanical ventilation is increasingly being used to continue ventilatory support in polymorbid patients following unsuccessful weaning. Recommendations and guidelines have been published by the German Respiratory Society (DGP).

  2. Single-lung ventilation in pediatric anesthesia.

    PubMed

    Choudhry, Dinesh K

    2005-12-01

    Single-lung ventilation is requested for an increasing spectrum of surgical procedures in infants and children. A clear understanding of the physiology of single-lung ventilation, the techniques of lung separation, and the technical skill necessary to apply these techniques are essential for an anesthesiologist practicing thoracic anesthesia. This article focuses on various devices available for single-lung ventilation in the pediatric age group, the relevant respiratory physiology, and the strategies that optimize oxygenation during one-lung anesthesia.

  3. Improved OCT imaging of lung tissue using a prototype for total liquid ventilation

    NASA Astrophysics Data System (ADS)

    Schnabel, Christian; Meissner, Sven; Koch, Edmund

    2011-06-01

    Optical coherence tomography (OCT) is used for imaging subpleural alveoli in animal models to gain information about dynamic and morphological changes of lung tissue during mechanical ventilation. The quality of OCT images can be increased if the refraction index inside the alveoli is matched to the one of tissue via liquid-filling. Thereby, scattering loss can be decreased and higher penetration depth and tissue contrast can be achieved. Until now, images of liquid-filled lungs were acquired in isolated and fixated lungs only, so that an in vivo measurement situation is not present. To use the advantages of liquid-filling for in vivo imaging of small rodent lungs, it was necessary to develop a liquid ventilator. Perfluorodecalin, a perfluorocarbon, was selected as breathing fluid because of its refraction index being similar to the one of water and the high transport capacity for carbon dioxide and oxygen. The setup is characterized by two independent syringe pumps to insert and withdraw the fluid into and from the lung and a custom-made control program for volume- or pressure-controlled ventilation modes. The presented results demonstrate the liquid-filling verified by optical coherence tomography and intravital microscopy (IVM) and the advantages of liquid-filling to OCT imaging of subpleural alveoli.

  4. High-Frequency Percussive Ventilation and Low Tidal Volume Ventilation in Burns: A Randomized Controlled Trial

    DTIC Science & Technology

    2010-01-01

    incidence of ventilator - associated pneumonia (VAP) in patients with inha- lation injury when supported with HFPV compared with conventional modes of...no. (%) 0 (0) 4 (13) .04 HFPV, high-frequency percussive ventilation ; LTV, low-tidal volume ventilation ; VAP, ventila- tor- associated pneumonia ...LTV, low-tidal volume ventilation ; VAP, ventila- tor- associated pneumonia ; NS, nonsignificant. aMean SD. 1973Crit Care Med 2010 Vol. 38, No. 10

  5. [Principles and function of mechanical ventilation: classification and modes of ventilators].

    PubMed

    Kelbel, C; Huntemann, M; Lorenz, J

    2006-04-01

    A spectrum of diseases is associated with the necessity for partial or total support of pulmonary ventilation. The insight into the function of ventilators and their modes reduces the spectrum of ventilatory support to a few basic principles. The knowledge enables the pulmonary intensivist to adapt mechanical ventilation to the individual patient's needs. This overview describes the technical aspects of mechanical ventilation and summarizes the variety of specific modes implied.

  6. Lung-protective ventilation in neonatology.

    PubMed

    van Kaam, Anton

    2011-01-01

    Ventilator-induced lung injury (VILI) is considered an important risk factor in the development of bronchopulmonary dysplasia (BPD) and is primarily caused by overdistension (volutrauma) and repetitive opening and collapse (atelectrauma) of terminal lung units. Lung-protective ventilation should therefore aim to reduce tidal volumes, and recruit and stabilize atelectatic lung units (open lung ventilation strategy). This review will summarize the available evidence on lung-protective ventilation in neonatology, discussing both high-frequency ventilation (HFV) and positive pressure ventilation (PPV). It shows that HFV does not appear to have a clear benefit over PPV, although most studies failed to apply a true open lung ventilation strategy during HFV. The evidence on the optimal tidal volume, positive end-expiratory pressure and the role for lung recruitment during lung-protective PPV is extremely limited. Volume-targeted ventilation seems to be a promising mode in terms of lung protection, but more studies are needed. Due to the lack of convincing evidence, lung-protective ventilation and modes seem to be implemented in daily clinical practice at a slow pace.

  7. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... not apply to closed ventilation systems for motors or generators, diffuser fans for refrigerated... 46 Shipping 4 2011-10-01 2011-10-01 false Power ventilation systems except machinery space ventilation systems. 111.103-1 Section 111.103-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND...

  8. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... not apply to closed ventilation systems for motors or generators, diffuser fans for refrigerated... 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...

  9. Improving the Blood Pressure Control With the ProActive Attitude of Hypertensive Patients Seeking Follow-up Services

    PubMed Central

    Tang, Shangfeng; Bishwajit, Ghose; Ji, Lu; Feng, Da; Fang, Haiqing; Fu, Hang; Shao, Tian; Shao, Piaopiao; Liu, Chunyan; Feng, Zhanchun; Luba, Tegene R.

    2016-01-01

    Abstract Proactive attitude of hypertensive patients seeking follow-up services (FUS) lies at the core of self-efficacy. However, few evidence have shown the activeness of seeking FUS in the context of blood pressure control among hypertensive patients. Improvements in follow-up visits may not just by services itself cause better control of blood pressure among hypertensive patients, rather due to the patient's pro-active attitude of the patient in seeking FUS. A cross-sectional study was carried out in selected rural regions of China to explore the association between blood pressure control and sociodemographic and economic variables and activeness of hypertensive patients in seeking FUS. The primary clinical outcome for this study was blood pressure control (systolic blood pressure <140 mmHg or diastolic blood pressure <90 mmHg) Out of the total 2321 participants with hypertension aged 35 years or older participated in this survey. Number of proactive FUS seekers were 3.17 times greater than those of passive seekers (odds ratio [OR] = 3.17, 95% confidence interval [CI] = 2.56–3.93, P < 0.001). In all subgroups, hypertensive patients who were seeking FUS actively were more likely to control blood pressure better than those seeking FUS passively. Proactive attitude of seeking follow-up services can improve blood pressure control among hypertensive patients. PMID:27057859

  10. [Evaluation of patient-ventilator synchrony of three new types of ventilators with pressure sunnort ventilation mode].

    PubMed

    Zhou, Juan; Wu, Hao; Cao, Desen

    2014-08-01

    Pressure-support ventilation (PSV) is a form of important ventilation mode. Patient-ventilator synchrony of pressure support ventilation can be divided into inspiration-triggered and expiration-triggered ones. Whether the ventilator can track the patient's inspiration and expiration very well or not is an important evaluating item of the performance of the ventilator. The ventilator should response to the patient's inspiration effort on time and deliver the air flow to the patient under various conditions, such as different patient's lung types and inspiration effort, etc. Similarly, the ventilator should be able to response to the patient's expiration action, and to decrease the patient lung's internal pressure rapidly. Using the Active Servo Lung (ASL5000) respiratory simulation system, we evaluated the spontaneous breathing of PSV mode on E5, Servo i and Evital XL. The following parameters, the delay time before flow to the patient starts once the trigger variable signaling the start of inspiration, the lowest inspiratory airway pressure generated prior to the initiation of PSV, etc. were measured.

  11. ORION Environmental Control and Life Support Systems Suit Loop and Pressure Control Analysis

    NASA Technical Reports Server (NTRS)

    Eckhardt, Brad; Conger, Bruce; Stambaugh, Imelda C.

    2015-01-01

    Under NASA's ORION Multi-Purpose Crew Vehicle (MPCV) Environmental Control and Life Support System (ECLSS) Project at Johnson Space Center's (JSC), the Crew and Thermal Systems Division has developed performance models of the air system using Thermal Desktop/FloCAD. The Thermal Desktop model includes an Air Revitalization System (ARS Loop), a Suit Loop, a Cabin Loop, and Pressure Control System (PCS) for supplying make-up gas (N2 and O2) to the Cabin and Suit Loop. The ARS and PCS are designed to maintain air quality at acceptable O2, CO2 and humidity levels as well as internal pressures in the vehicle Cabin and during suited operations. This effort required development of a suite of Thermal Desktop Orion ECLSS models to address the need for various simulation capabilities regarding ECLSS performance. An initial highly detailed model of the ARS Loop was developed in order to simulate rapid pressure transients (water hammer effects) within the ARS Loop caused by events such as cycling of the Pressurized Swing Adsorption (PSA) Beds and required high temporal resolution (small time steps) in the model during simulation. A second ECLSS model was developed to simulate events which occur over longer periods of time (over 30 minutes) where O2, CO2 and humidity levels, as well as internal pressures needed to be monitored in the cabin and for suited operations. Stand-alone models of the PCS and the Negative Pressure relief Valve (NPRV) were developed to study thermal effects within the PCS during emergency scenarios (Cabin Leak) and cabin pressurization during vehicle re-entry into Earth's atmosphere. Results from the Orion ECLSS models were used during Orion Delta-PDR (July, 2014) to address Key Design Requirements (KDR's) for Suit Loop operations for multiple mission scenarios.

  12. Effectiveness of Nicardipine for Blood Pressure Control in Patients with Subarachnoid Hemorrhage

    PubMed Central

    Kim, Sang Yong; Kim, Seong Min; Park, Moon Sun; Kim, Han Kyu; Park, Ki Seok

    2012-01-01

    Objective The purpose of the study is to determine the effectiveness and safety of nicardipine infusion for controlling blood pressure in patients with subarachnoid hemorrhage (SAH). Methods We prospectively evaluated 52 patients with SAH and treated with nicardipine infusion for blood pressure control in a 29 months period. The mean blood pressure of pre-injection, bolus injection and continuous injection period were compared. This study evaluated the effectiveness of nicardipine for each Fisher grade, for different dose of continuous nicardipine infusion, and for the subgroups of systolic blood pressure. Results The blood pressure measurement showed that the mean systolic blood pressure / diastolic blood pressure (SBP/DBP) in continuous injection period (120.9/63.0 mmHg) was significantly lower than pre-injection period (145.6/80.3 mmHg) and bolus injection period (134.2/71.3 mmHg), and these were statistically significant (p < 0.001). In each subgroups of Fisher grade and different dose, SBP/DBP also decreased after the use of nicardipine. These were statistically significant (p < 0.05), but there was no significant difference in effectiveness between subgroups (p > 0.05). Furthermore, controlling blood pressure was more effective when injecting higher dose of nicardipine in higher SBP group rather than injecting lower dose in lower SBP group, and it also was statistically significant (p < 0.05). During the infusion, hypotension and cardiogenic problems were transiently combined in five cases. However, patients recovered without any complications. Conclusion Nicardipine is an effective and safe agent for controlling acutely elevated blood pressure after SAH. A more systemic study with larger patients population will provide significant results and will bring solid evidence on effectiveness of nicardipine in SAH. PMID:23210033

  13. 46 CFR 153.312 - Ventilation system standards.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... system must meet the following: (a) A ventilation system exhaust duct must discharge no less than 10 m... ventilation duct, a ventilation duct must not pass through a machinery room, an accommodation space,...

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

    PubMed

    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.

  15. Cytokine and chemokine mRNA expression profiles in tracheobronchial lymph nodes from pigs singularly infected or coinfected with porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae (MHYO)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to determine cytokine and chemokine mRNA expression profiles in tracheobronchial lymph nodes from pigs singularly infected with porcine circovirus type 2 (PCV2), Mycoplasma hyopneumoniae (MHYO), or coinfected with both. Twenty-eight pigs were randomly assigned to one ...

  16. Dynamic Behaviour of Ventilated Hydrofoils.

    NASA Astrophysics Data System (ADS)

    Kjeldsen, Morten; Arndt, Roger; Wosnik, Martin

    2006-11-01

    In certain types of pumping applications oscillations are induced by operation with liquids containing a free gas load. In order to understand the physics of this process, a series of tests with a ventilated A 2D NACA 0015 hydrofoil were performed in the water tunnel at the St. Anthony Falls Laboratory of the University of Minnesota. The special bubble removal feature of the water tunnel allowed continuous ventilation without experiencing visible bubbles upstream the hydrofoil. These studies build on previous work on cavitation-induced oscillations. Gas injection studies were made over a range of gas flow rates and test section pressure. The results clearly show that lift oscillations increase in intensity when the gas load is increased. The point of maximum unsteadiness is also associated the rapid decline of the foil performance as measured as average lift. Further increase of the gas injection load gives a steady behaviour with almost no lift. These experiments are compared with traditional cavitation experiments. The similarities between gas injection- and cavitation induced unsteadiness on the hydrofoil are many, but the amplitude of lift oscillations found on the foil with gas injection corresponds to about 50% of that found for cavitating hydrofoils. The fact that the oscillations are periodic leads to the consideration of both passive and active control.

  17. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) of the home's floor area. The total area of ventilation openings may be reduced to one square foot (ft.2) for every 1,500 square feet (ft.2) of the home's floor area, where a uniform 6-mil polyethylene... surface beneath the entire floor area of the home. (b) Ventilation openings must be placed as high...

  18. 46 CFR 111.105-21 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Ventilation. 111.105-21 Section 111.105-21 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... location has the classification of that location. Each fan for ventilation of a hazardous location must...

  19. 14 CFR 121.219 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Ventilation. 121.219 Section 121.219 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS..., FLAG, AND SUPPLEMENTAL OPERATIONS Special Airworthiness Requirements § 121.219 Ventilation....

  20. 14 CFR 121.219 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Ventilation. 121.219 Section 121.219 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS..., FLAG, AND SUPPLEMENTAL OPERATIONS Special Airworthiness Requirements § 121.219 Ventilation....

  1. 14 CFR 121.219 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Ventilation. 121.219 Section 121.219 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS..., FLAG, AND SUPPLEMENTAL OPERATIONS Special Airworthiness Requirements § 121.219 Ventilation....

  2. 14 CFR 121.219 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Ventilation. 121.219 Section 121.219 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS..., FLAG, AND SUPPLEMENTAL OPERATIONS Special Airworthiness Requirements § 121.219 Ventilation....

  3. 14 CFR 23.831 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ventilation. 23.831 Section 23.831 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... Cargo Accommodations § 23.831 Ventilation. (a) Each passenger and crew compartment must be...

  4. 14 CFR 121.219 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Ventilation. 121.219 Section 121.219 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS..., FLAG, AND SUPPLEMENTAL OPERATIONS Special Airworthiness Requirements § 121.219 Ventilation....

  5. Infiltration in ASHRAE's Residential Ventilation Standards

    SciTech Connect

    Sherman, Max

    2008-10-01

    The purpose of ventilation is to dilute or remove indoor contaminants that an occupant could be exposed to. It can be provided by mechanical or natural means. ASHRAE Standards including standards 62, 119, and 136 have all considered the contribution of infiltration in various ways, using methods and data from 20 years ago. The vast majority of homes in the United States and indeed the world are ventilated through natural means such as infiltration caused by air leakage. Newer homes in the western world are tight and require mechanical ventilation. As we seek to provide acceptable indoor air quality at minimum energy cost, it is important to neither over-ventilate norunder-ventilate. Thus, it becomes critically important to correctly evaluate the contribution infiltration makes to both energy consumption and equivalent ventilation. ASHRAE Standard 62.2 specifies how much mechanical ventilation is considered necessary to provide acceptable indoor air quality, but that standard is weak on how infiltration can contribute towards meeting the total requirement. In the past ASHRAE Standard 136 was used to do this, but new theoretical approaches and expanded weather data have made that standard out of date. This article will describe how to properly treat infiltration as an equivalent ventilation approach and then use new data and these new approaches to demonstrate how these calculations might be done both in general and to update Standard 136.

  6. Ventilation Technical Guide, 2nd Edition

    DTIC Science & Technology

    2013-04-12

    Proficiency Codes (see Table 2) Indicate Required Training Levela 3- lvl Course 5- lvl OJT 5- lvl CDCb 7- lvl Course 4.13 Mechanical Ventilation...for deficient ventilation systems A - B - a7- lvl OJT & Advanced Course have no required training level. bCDC = Career

  7. 14 CFR 23.831 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ventilation system must be designed to provide each occupant with at least 0.55 pounds of fresh air per minute... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Ventilation. 23.831 Section 23.831... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Personnel...

  8. 14 CFR 23.831 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ventilation system must be designed to provide each occupant with at least 0.55 pounds of fresh air per minute... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Ventilation. 23.831 Section 23.831... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Personnel...

  9. 14 CFR 23.831 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ventilation. 23.831 Section 23.831... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Personnel and Cargo Accommodations § 23.831 Ventilation. (a) Each passenger and crew compartment must be...

  10. 14 CFR 23.831 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ventilation system must be designed to provide each occupant with at least 0.55 pounds of fresh air per minute... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Ventilation. 23.831 Section 23.831... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Personnel...

  11. Preoperational test report, primary ventilation system

    SciTech Connect

    Clifton, F.T.

    1997-11-04

    This represents a preoperational test report for Primary Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space filtered venting of tanks AY101, AY102, AZ101, AZ102. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  12. Commissioning Ventilated Containment Systems in the Laboratory

    SciTech Connect

    Not Available

    2008-08-01

    This Best Practices Guide focuses on the specialized approaches required for ventilated containment systems, understood to be all components that drive and control ventilated enclosures and local exhaust systems within the laboratory. Geared toward architects, engineers, and facility managers, this guide provides information about technologies and practices to use in designing, constructing, and operating operating safe, sustainable, high-performance laboratories.

  13. New modes of assisted mechanical ventilation.

    PubMed

    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.

  14. 29 CFR 1910.94 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... replacement system complying with the preceding section, general heating of the building in which the spray... maintained at not less than 65 °F. when the exhaust system is in operation or the general heating system... handled by an exhaust ventilation system. (viii) Exhaust ventilation system. A system for...

  15. 29 CFR 1910.94 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... replacement system complying with the preceding section, general heating of the building in which the spray... maintained at not less than 65 °F. when the exhaust system is in operation or the general heating system... handled by an exhaust ventilation system. (viii) Exhaust ventilation system. A system for...

  16. 29 CFR 1910.94 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... replacement system complying with the preceding section, general heating of the building in which the spray... maintained at not less than 65 °F. when the exhaust system is in operation or the general heating system... handled by an exhaust ventilation system. (viii) Exhaust ventilation system. A system for...

  17. 29 CFR 1910.94 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... replacement system complying with the preceding section, general heating of the building in which the spray... maintained at not less than 65 °F. when the exhaust system is in operation or the general heating system... handled by an exhaust ventilation system. (viii) Exhaust ventilation system. A system for...

  18. Intraocular Pressure Control after Trabeculectomy, Phacotrabeculectomy and Phacoemulsification in a Hispanic Population

    PubMed Central

    L Jung, Jennifer; Isida-Llerandi, Cristina G; Lazcano-Gomez, Gabriel; SooHoo, Jeffrey R

    2014-01-01

    ABSTRACT Purpose: To compare the efficacy of different surgical strategies for intraocular pressure (IOP) control in Hispanic glaucoma patients with and without visually significant cataracts. Design: Comparative retrospective consecutive case series. Methods: The charts of 153 consecutive patients with primary open angle glaucoma who underwent either trabeculectomy alone (n = 51), phacotrabeculectomy (n = 51), or phacoemulsification alone (n = 51) were reviewed to compare IOP control, the number of glaucoma medications required postoperatively, and the inci dence of surgical complications. Results: Preoperative IOP was 17.5 ± 5.2 mm Hg in the trabe-culectomy group, 15.4 ± 4.5 mm Hg in the phacotrabeculectomy group and 13.9 ± 2.9 mm Hg in the phacoemulsification group (p < 0.001 for all comparisons). Mean IOP reduction from baseline was 4.2 ± 6.9 (24.6%) for the trabeculectomy group, 2.9 ± 5.0 (20.8%) for the phacotrabeculectomy group, and 0.9 ± 3.4 (6.5%) for the phacoemulsification group (p = 0.009). The number of IOP-lowering medications required postoperatively decreased significantly in all three groups (p = 0.001). The rate of early and late postoperative complications was similar between the trabeculectomy and phacotrabeculectomy groups and less for the phacoemulsification group. Conclusion: Trabeculectomy and phacotrabeculectomy are both viable surgical options for managing open angle glau coma. Both resulted in similar rates of success, IOP reduction, decrease in use of IOP-lowering medications and post operative complication rates. Phacoemulsification alone had a lower success rate and greater need for postoperative IOP-lowering medications compared to trabeculectomy alone or phacotrabeculectomy. Phacoemulsification alone may be a reasonable option for patients with visually significant cataract and lower baseline IOP. How to cite this article: Jung JL, Isida-Llerandi CG, Lazcano-Gomez G, SooHoo JR, Kahook MY. Intraocular Pressure Control after

  19. Intraocular Pressure Control after Implantation of an Ahmed Glaucoma Valve in Eyes with a Failed Trabeculectomy

    PubMed Central

    Schimiti, Rui B; Abe, Ricardo Y; Tavares, Carla M; Vasconcellos, Jose PC; Costa, Vital P

    2016-01-01

    Aim To evaluate the results of Ahmed glaucoma valve (AGV) in eyes with a failed trabeculectomy. Materials and methods This retrospective study evaluated 61 eyes with a failed trabeculectomy that underwent implantation of an AGV due to uncontrolled intraocular pressure (IOP) on maximal medical therapy. Success was defined as IOP ≤ 21 mm Hg (criterion 1) or 20% reduction in IOP (criterion 2) with or without antiglaucoma medications. Persistent hypotony, loss of light perception, and reoperation for IOP control were defined as failure. Results Mean preoperative IOP and mean lOPs at 6, 12, and 24 months were 21.93 ± 6.32 mm Hg (n = 61), 14.15 ± 4.33 mm Hg (n = 59), 13.21 ± 4.44 mm Hg (n = 56), and 13.60 ± 3.27 mm Hg (n = 25) respectively. Mean number of antiglaucoma medications preoperatively and at 6, 12, and 24 months was 3.95 ± 0.85, 2.19 ± 1.38, 2.48 ± 1.44, and 2.40 ± 1.32 respectively. The reductions in the number of medications and IOP measurements were statistically significant at all time intervals (p < 0.001, Wilcoxon signed rank test). According to criterion 1, the Kaplan-Meier survival curve disclosed success rates of 75% at 12 and 24 months. According to criterion 2, the success rates were 57% at 12 months and 55% at 24 months. The most frequent complications were hypertensive phase (18%) and shallow anterior chamber (16.4%). Conclusion The AGV may effectively reduce IOP in eyes that had a failed trabeculectomy. Clinical significance The AGV is an alternative in eyes with a failed trabeculectomy. How to cite this article Schimiti RB, Abe RY, Tavares CM, Vasconcellos JPC, Costa VP. Intraocular Pressure Control after Implantation of an Ahmed Glaucoma Valve in Eyes with a Failed Trabeculectomy. J Curr Glaucoma Pract 2016;10(3):97-103. PMID:27857489

  20. [Comparison of volume preset and pressure preset ventilators during daytime nasal ventilation in chronic respiratory failure].

    PubMed

    Perrin, C; Wolter, P; Berthier, F; Tamisier, R; Jullien, V; Lemoigne, F; Blaive, B

    2001-02-01

    Both volume preset and pressure preset ventilators are available for domiciliary nasal ventilation. Owing to their technical characteristics, it has been suggested that impaired ventilatory mechanics might cause a drop in the tidal volume (Vt) delivered by pressure preset devices, thereby placing mechanical ventilation at risk of inefficacy. We have assessed two ventilator systems (one pressure preset and one volume preset) with regard to the tidal volume and end-tidal carbon dioxide tension (PetCO(2)) changes that may be achieved in a group of awake patients with stable chronic respiratory failure (CRF). Eleven patients with stable CRF were ventilated in the assist/control mode for two consecutive one-hour periods. One ventilator was tested each hour, in random order. The VIGIL'AIR(R) system was used to record Vt, Respiratory Rate (RR), and Inspiratory/Expiratory ratio (I/E). The deviation E (E=preset value - measured value) was calculated for each measurement. Changes in PetCO(2) and arterial oxygen saturation were determined respectively by a capnometer and a pulse oximeter. Comparison of the mean deviation of Vt calculated for the two ventilators revealed a difference in patients with chronic obstructive pulmonary disease (COPD). The deviation was greatest with the pressure preset ventilator (PPV), which gave mean measured values higher than the mean preset values. The same comparison failed to reveal any difference in restrictive CRF. Comparison of the volume preset and pressure preset ventilators for RR, I/E and PetCO(2) did not reveal any difference. Compared to the volume preset ventilator, the efficacy of PPV to ventilate is not affected by the restrictive or obstructive nature of CRF. Our results show that pressure-preset ventilator is an adequate alternative to the volume-preset device for daytime non invasive ventilation in chronic respiratory insufficiency.

  1. Implementation of a Hybrid Controller for Ventilation Control Using Soft Computing

    SciTech Connect

    Craig G. Rieger; D. Subbaram Naidu

    2005-06-01

    Many industrial facilities utilize pressure control gradients to prevent migration of hazardous species from containment areas to occupied zones, often using Proportional-Integral-Derivative (PID) control systems. When operators rebalance the facility, variation from the desired gradients can occur and the operating conditions can change enough that the PID parameters are no longer adequate to maintain a stable system. As the goal of the ventilation control system is to optimize the pressure gradients and associated flows for the facility, Linear Quadratic Tracking (LQT) is a method that provides a time-based approach to guiding facility interactions. However, LQT methods are susceptible to modeling and measurement errors, and therefore the additional use of Soft Computing methods are proposed for implementation to account for these errors and nonlinearities.

  2. Infiltration as Ventilation: Weather-Induced Dilution

    SciTech Connect

    Sherman, Max H.; Turner, William J.N.; Walker, Iain S.

    2011-06-01

    The purpose of outdoor air ventilation is to dilute or remove indoor contaminants to which occupants are exposed. It can be provided by mechanical or natural means. In most homes, especially older homes, weather-driven infiltration provides the dominant fraction of the total ventilation. As we seek to provide good indoor air quality at minimum energy cost, it is important to neither over-ventilate nor under-ventilate. Thus, it becomes critically important to evaluate correctly the contribution infiltration makes to the total outdoor air ventilation rate. Because weather-driven infiltration is dependent on building air leakage and weather-induced pressure differences, a given amount of air leakage will provide different amounts of infiltration. Varying rates of infiltration will provide different levels of contaminant dilution and hence effective ventilation. This paper derives these interactions and then calculates the impact of weather-driven infiltration for different climates. A new “N-factor” is introduced to provide a convenient method for calculating the ventilation contribution of infiltration for over 1,000 locations across North America. The results of this work could be used in indoor air quality standards (specifically ASHRAE 62.2) to account for the contribution of weather-driven infiltration towards the dilution of indoor pollutants.

  3. Characteristics of coal mine ventilation air flows.

    PubMed

    Su, Shi; Chen, Hongwei; Teakle, Philip; Xue, Sheng

    2008-01-01

    Coal mine methane (CMM) is not only a greenhouse gas but also a wasted energy resource if not utilised. Underground coal mining is by far the most important source of fugitive methane emissions, and approximately 70% of all coal mining related methane is emitted to the atmosphere through mine ventilation air. Therefore, research and development on mine methane mitigation and utilisation now focuses on methane emitted from underground coal mines, in particular ventilation air methane (VAM) capture and utilisation. To date, most work has focused on the oxidation of very low concentration methane. These processes may be classified based on their combustion kinetic mechanisms into thermal oxidation and catalytic oxidation. VAM mitigation/utilisation technologies are generally divided into two basic categories: ancillary uses and principal uses. However, it is possible that the characteristics of ventilation air flows, for example the variations in methane concentration and the presence of certain compounds, which have not been reported so far, could make some potential VAM mitigation and utilisation technologies unfeasible if they cannot cope with the characteristics of mine site ventilation air flows. Therefore, it is important to understand the characteristics of mine ventilation air flows. Moreover, dust, hydrogen sulphide, sulphur dioxide, and other possible compounds emitted through mine ventilation air into the atmosphere are also pollutants. Therefore, this paper presents mine-site experimental results on the characteristics of mine ventilation air flows, including methane concentration and its variations, dust loadings, particle size, mineral matter of the dust, and other compounds in the ventilation air flows. The paper also discusses possible correlations between ventilation air characteristics and underground mining activities.

  4. [Classification and terminology of artificial lung ventilation].

    PubMed

    Gal'perin, Iu S

    2005-01-01

    The author considers the main features of a prepared edition of the international standard ISO 4135:2001 "Equipment for anesthesia and artificial ventilation. Glossary" as the state standard of Russia. He shows methods for classification of the modes of ventilation support. A classification scheme of its procedures is proposed, by giving necessary notes. The abbreviations of these procedures are given in the Russian and English languages. The shorthand notations of airways gas pressure in the characteristic points of a respiratory cycle are clarified in detail and on this basis the procedures for limiting inspiration pressure during controlled artificial ventilation.

  5. Special Considerations in Neonatal Mechanical Ventilation.

    PubMed

    Dalgleish, Stacey; Kostecky, Linda; Charania, Irina

    2016-12-01

    Care of infants supported with mechanical ventilation is complex, time intensive, and requires constant vigilance by an expertly prepared health care team. Current evidence must guide nursing practice regarding ventilated neonates. This article highlights the importance of common language to establish a shared mental model and enhance clear communication among the interprofessional team. Knowledge regarding the underpinnings of an open lung strategy and the interplay between the pathophysiology and individual infant's response to a specific ventilator strategy is most likely to result in a positive clinical outcome.

  6. Ventilatory management of one-lung ventilation.

    PubMed

    Della Rocca, G; Coccia, C

    2011-05-01

    Hypoxemia is considered to be the most important challenge during one-lung ventilation (OLV). Recent studies, however, have shown that one-lung ventilation can involve some lung damage and can therefore be per se a cause of hypoxemia. OLV can be associated to an injury: but the techniques used to improve oxygenation may also damage the lung. A new ventilator approach should be used and applied with regards to what is so far known in terms of "lung protection" also during OLV.

  7. 21 CFR 868.5955 - Intermittent mandatory ventilation attachment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... providing mechanical ventilation at a preset rate. (b) Classification. Class II (performance standards). ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intermittent mandatory ventilation attachment. 868... mandatory ventilation attachment. (a) Identification. An intermittent mandatory ventilation (IMV)...

  8. 46 CFR 72.15-15 - Ventilation for closed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 3 2014-10-01 2014-10-01 false Ventilation for closed spaces. 72.15-15 Section 72.15-15... ARRANGEMENT Ventilation § 72.15-15 Ventilation for closed spaces. (a) All enclosed spaces within the vessel... spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings...

  9. 46 CFR 72.15-15 - Ventilation for closed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Ventilation for closed spaces. 72.15-15 Section 72.15-15... ARRANGEMENT Ventilation § 72.15-15 Ventilation for closed spaces. (a) All enclosed spaces within the vessel... spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings...

  10. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop the ventilation, one of which may be the...

  11. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop the ventilation, one of which may be the...

  12. 46 CFR 72.15-15 - Ventilation for closed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 3 2013-10-01 2013-10-01 false Ventilation for closed spaces. 72.15-15 Section 72.15-15... ARRANGEMENT Ventilation § 72.15-15 Ventilation for closed spaces. (a) All enclosed spaces within the vessel... spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings...

  13. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Ventilation for enclosed spaces. 108.181 Section 108.181... AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for enclosed spaces. (a) Each enclosed space must be vented or ventilated. (b) There must be a means to close each vent...

  14. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop the ventilation, one of which may be the...

  15. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Ventilation for enclosed spaces. 108.181 Section 108.181... AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for enclosed spaces. (a) Each enclosed space must be vented or ventilated. (b) There must be a means to close each vent...

  16. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Ventilation for enclosed spaces. 108.181 Section 108.181... AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for enclosed spaces. (a) Each enclosed space must be vented or ventilated. (b) There must be a means to close each vent...

  17. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Mechanical ventilation system: Standards. 154.1205... Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each exhaust type mechanical ventilation system required under § 154.1200 (a) must have ducts...

  18. 46 CFR 111.103-7 - Ventilation stop stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Ventilation stop stations. 111.103-7 Section 111.103-7...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-7 Ventilation stop stations. Each ventilation stop... Case of Fire Break Glass and Operate Switch to Stop Ventilation;” (c) Have the “stop” position of...

  19. 30 CFR 77.1911 - Ventilation of slopes and shafts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Ventilation of slopes and shafts. 77.1911... COAL MINES Slope and Shaft Sinking § 77.1911 Ventilation of slopes and shafts. (a) All slopes and shafts shall be ventilated by mechanical ventilation equipment during development. Such equipment...

  20. 49 CFR 192.187 - Vaults: Sealing, venting, and ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Vaults: Sealing, venting, and ventilation. 192.187... Components § 192.187 Vaults: Sealing, venting, and ventilation. Each underground vault or closed top pit... ventilating effect of a pipe 4 inches (102 millimeters) in diameter; (2) The ventilation must be enough...

  1. 21 CFR 868.5955 - Intermittent mandatory ventilation attachment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Intermittent mandatory ventilation attachment. 868... mandatory ventilation attachment. (a) Identification. An intermittent mandatory ventilation (IMV) attachment... providing mechanical ventilation at a preset rate. (b) Classification. Class II (performance standards)....

  2. 21 CFR 868.5955 - Intermittent mandatory ventilation attachment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Intermittent mandatory ventilation attachment. 868... mandatory ventilation attachment. (a) Identification. An intermittent mandatory ventilation (IMV) attachment... providing mechanical ventilation at a preset rate. (b) Classification. Class II (performance standards)....

  3. 21 CFR 868.5955 - Intermittent mandatory ventilation attachment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Intermittent mandatory ventilation attachment. 868... mandatory ventilation attachment. (a) Identification. An intermittent mandatory ventilation (IMV) attachment... providing mechanical ventilation at a preset rate. (b) Classification. Class II (performance standards)....

  4. 49 CFR 192.187 - Vaults: Sealing, venting, and ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Vaults: Sealing, venting, and ventilation. 192.187... Components § 192.187 Vaults: Sealing, venting, and ventilation. Each underground vault or closed top pit... ventilating effect of a pipe 4 inches (102 millimeters) in diameter; (2) The ventilation must be enough...

  5. 46 CFR 111.103-7 - Ventilation stop stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Ventilation stop stations. 111.103-7 Section 111.103-7...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-7 Ventilation stop stations. Each ventilation stop... Case of Fire Break Glass and Operate Switch to Stop Ventilation;” (c) Have the “stop” position of...

  6. 21 CFR 868.5955 - Intermittent mandatory ventilation attachment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Intermittent mandatory ventilation attachment. 868... mandatory ventilation attachment. (a) Identification. An intermittent mandatory ventilation (IMV) attachment... providing mechanical ventilation at a preset rate. (b) Classification. Class II (performance standards)....

  7. 46 CFR 38.20-10 - Ventilation-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Ventilation-T/ALL. 38.20-10 Section 38.20-10 Shipping... Ventilation § 38.20-10 Ventilation—T/ALL. (a) A power ventilation system shall be provided for compartments... equipped with power ventilation of the exhaust type having capacity sufficient to effect a complete...

  8. 30 CFR 77.1911 - Ventilation of slopes and shafts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Ventilation of slopes and shafts. 77.1911... COAL MINES Slope and Shaft Sinking § 77.1911 Ventilation of slopes and shafts. (a) All slopes and shafts shall be ventilated by mechanical ventilation equipment during development. Such equipment...

  9. 46 CFR 108.185 - Ventilation for enclosed classified locations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Ventilation § 108.185 Ventilation for enclosed classified locations. (a) The ventilation system for each enclosed classified location must be... 46 Shipping 4 2013-10-01 2013-10-01 false Ventilation for enclosed classified locations....

  10. 30 CFR 77.1911 - Ventilation of slopes and shafts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Ventilation of slopes and shafts. 77.1911... COAL MINES Slope and Shaft Sinking § 77.1911 Ventilation of slopes and shafts. (a) All slopes and shafts shall be ventilated by mechanical ventilation equipment during development. Such equipment...

  11. 46 CFR 38.20-10 - Ventilation-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... and accessible from the cargo handling deck. Such ventilation systems shall be designed to preclude... 46 Shipping 1 2014-10-01 2014-10-01 false Ventilation-T/ALL. 38.20-10 Section 38.20-10 Shipping... Ventilation § 38.20-10 Ventilation—T/ALL. (a) A power ventilation system shall be provided for...

  12. 46 CFR 108.185 - Ventilation for enclosed classified locations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Ventilation § 108.185 Ventilation for enclosed classified locations. (a) The ventilation system for each enclosed classified location must be... 46 Shipping 4 2012-10-01 2012-10-01 false Ventilation for enclosed classified locations....

  13. 46 CFR 108.185 - Ventilation for enclosed classified locations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Ventilation § 108.185 Ventilation for enclosed classified locations. (a) The ventilation system for each enclosed classified location must be... 46 Shipping 4 2014-10-01 2014-10-01 false Ventilation for enclosed classified locations....

  14. 30 CFR 57.8532 - Opening and closing ventilation doors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Opening and closing ventilation doors. 57.8532 Section 57.8532 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Ventilation Underground Only § 57.8532 Opening and closing ventilation doors. When ventilation control...

  15. 30 CFR 57.8532 - Opening and closing ventilation doors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Opening and closing ventilation doors. 57.8532 Section 57.8532 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Ventilation Underground Only § 57.8532 Opening and closing ventilation doors. When ventilation control...

  16. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Mechanical ventilation system: Standards. 154.1205... Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each exhaust type mechanical ventilation system required under § 154.1200 (a) must have ducts...

  17. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Mechanical ventilation system: General. 154.1200 Section... Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a... cargo handling equipment must have a fixed, exhaust-type mechanical ventilation system. (b)...

  18. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Mechanical ventilation system: General. 154.1200 Section... Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a... cargo handling equipment must have a fixed, exhaust-type mechanical ventilation system. (b)...

  19. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Mechanical ventilation system: Standards. 154.1205... Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each exhaust type mechanical ventilation system required under § 154.1200 (a) must have ducts...

  20. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Mechanical ventilation system: Standards. 154.1205... Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each exhaust type mechanical ventilation system required under § 154.1200 (a) must have ducts...

  1. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Mechanical ventilation system: General. 154.1200 Section... Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a... cargo handling equipment must have a fixed, exhaust-type mechanical ventilation system. (b)...

  2. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Each exhaust type mechanical ventilation system required under § 154.1200 (a) must have ducts for... duct under paragraph (a) of this section must be at least 10 m (32.8 ft.) from ventilation intakes and... operational controls outside the ventilated space. (g) No ventilation duct for a gas-dangerous space may...

  3. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Ventilation for enclosed spaces. 108.181 Section 108.181... AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for enclosed spaces. (a) Each enclosed space must be vented or ventilated. (b) There must be a means to close each vent...

  4. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop the ventilation, one of which may be the...

  5. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop the ventilation, one of which may be the...

  6. 46 CFR 72.15-15 - Ventilation for closed spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Ventilation for closed spaces. 72.15-15 Section 72.15-15... ARRANGEMENT Ventilation § 72.15-15 Ventilation for closed spaces. (a) All enclosed spaces within the vessel... spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings...

  7. 46 CFR 72.15-15 - Ventilation for closed spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 3 2011-10-01 2011-10-01 false Ventilation for closed spaces. 72.15-15 Section 72.15-15... ARRANGEMENT Ventilation § 72.15-15 Ventilation for closed spaces. (a) All enclosed spaces within the vessel... spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings...

  8. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation for enclosed spaces. 108.181 Section 108.181... AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for enclosed spaces. (a) Each enclosed space must be vented or ventilated. (b) There must be a means to close each vent...

  9. Serotype distribution and susceptibility to penicillin and erythromycin among noninvasive or colonization isolates of Streptococcus pneumoniae in northern Japan: a cross-sectional study in the pre-PCV7 routine immunization period.

    PubMed

    Kawaguchiya, Mitsuyo; Urushibara, Noriko; Ghosh, Souvik; Kuwahara, Osamu; Morimoto, Shigeo; Ito, Masahiko; Kudo, Kenji; Kobayashi, Nobumichi

    2014-10-01

    Distribution of serotypes, prevalence of resistance to penicillin and/or erythromycin (EM), and its genetic traits were analyzed for a total of 1,061 noninvasive or colonization isolates of Streptococcus pneumoniae (998 and 61 isolates from children and adults, respectively) in Hokkaido, northern main island of Japan, in the year 2011, the pre-PCV7 routine immunization period. Serotype deduction was performed by sequential multiplex polymerase chain reaction (PCR), employing mutagenic PCR-restriction fragment length polymorphism for discrimination of 6A/C and 6B/D. Unaltered three PBP genes and macrolide resistance genes erm(B) and mef(A/E) were detected by multiplex PCR. Among isolates from children, 25 serotypes, including the prevalent types 6B (17.5%), 19F (15.6%), 23F (12.2%), and 6C (11.6%), were identified, revealing the PCV7 and PCV13 coverage rates as 48.2% and 60.3%, respectively, while serotype 3 was the most frequent (19.0%) among isolates from adults. Most of the pediatric isolates (96.8%) exhibited resistance to EM (minimum inhibitory concentration [MIC], ≥1 μg/ml), with a higher prevalence of erm(B) (67.2%) than mef(A/E) (39.7%). erm(B) was associated with high-level EM resistance (MIC, ≥128 μg/ml) and distributed at high detection rates to major serotypes 23F (85.2%) and 6B (85.1%), as well as minor serotypes 3, 10A, 14, 15B, 15C, 19A, and 23A (>90%). While penicillin-resistant S. pneumoniae (PRSP) (penicillin G-MIC, 2-3 μg/ml) was detected in 7.8% of isolates from children, the most common PBP gene genotype was gPRSP (three altered genes pbp1a, 2x, and 2b; 38.3%), which was detected at higher rates (>60%) in the dominant serotypes 23F, 6B, and 19F, and minor serotypes 6D and 15A. Dominant serotypes in the S. pneumoniae isolates were generally similar to those reported for invasive strains, despite lower coverage rates by PCV7/13. The importance of further surveillance on incidence and drug resistance in the post-PCV7 period was

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

    SciTech Connect

    Turner, William; Walker, Iain

    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.

  11. 46 CFR 72.05-50 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... periodic inspection by means of a hinged or bolted plate in the duct. The damper and the portion of duct... ventilator, and the duct shall be insulated to meet the applicable requirements of tables 72.05-10(d) and...

  12. 46 CFR 72.05-50 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... periodic inspection by means of a hinged or bolted plate in the duct. The damper and the portion of duct... ventilator, and the duct shall be insulated to meet the applicable requirements of tables 72.05-10(d) and...

  13. 46 CFR 72.05-50 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... periodic inspection by means of a hinged or bolted plate in the duct. The damper and the portion of duct... ventilator, and the duct shall be insulated to meet the applicable requirements of tables 72.05-10(d) and...

  14. 'Elective' ventilation: an unethical and harmful misnomer?

    PubMed

    Stammers, Trevor

    2013-01-01

    The demand for organs prompted the first use of elective ventilation in the UK in the 1990s. Recently the shortfall in supply of organs has once again prompted calls for elective ventilation to be instituted even in patients who are not brain dead. This paper proposes that the term 'elective' ventilation is a misnomer and the term non-therapeutic ventilation (NTV) should be used instead. It is further argued that the practice of NTV in cases of severe stroke is unethical and has the potential of causing a variety of harms to the patient, their relatives, and the healthcare professionals working in transplant teams and this may result in a backlash of reductions in the number of organ donations.

  15. Waste tank ventilation system waste material accumulations

    SciTech Connect

    Van Vleet, R.J., Westinghouse Hanford

    1996-08-06

    This paper calculates the amount of material that accumulates in the ventilation systems of various Tank Waste Remediation System facilities and estimates the amount of material that could be released due to a rapid pressurization.

  16. Ventilation Guidance for Spray Polyurethane Foam Application

    EPA Pesticide Factsheets

    Properly designed ventilation can reduce airborne levels of aerosols, mists, and vapors generated during spray application and can help protect SPF applicators, helpers, and others who may be working in adjacent areas.

  17. Speech for People with Tracheostomies or Ventilators

    MedlinePlus

    ... his or her life is undergoing dramatic change. Young children with tracheostomies do not get to explore making sounds. They also may have limited social interactions that are critical to the ... impact does having a ventilator have on speech? For ...

  18. Uneven ventilation of the lung following trauma.

    PubMed Central

    Lozman, J; Dutton, R E; Newell, J; Powers, S R

    1977-01-01

    Ventilatory function of the lungs has been studied in 13 post-trauma patients using a two compartment analysis. The analysis is based upon a model of the lung which describes a nitrogen washout curve in terms of fast and slowly ventilated compartments. Data output from a digital computer provides values that compare the fractions of the alveolar ventilation and volume of the two compartments. All patients on initial investigation had large identifiable slow spaces. Subsequent evaluation at a time of clinical improvement showed that the ventilation of the slow space had increased significantly (P less than .003), whereas no change was evident in the volume fraction. The ventilation to volume ratio of the slow space, measured on these two separate occasions increased in twelve of the patients studied. An increase in this ratio correlated with improvement in the patient's clinical condition. PMID:921355

  19. [Cardiopulmonary resuscitation: risks and benefits of ventilation].

    PubMed

    Cordioli, Ricardo Luiz; Garelli, Valentina; Lyazidi, Aissam; Suppan, Laurent; Savary, Dominique; Brochard, Laurent; Richard, Jean-Christophe M

    2013-12-11

    Knowledge of the physiological mechanisms that govern cardiopulmonary interactions during cardiopulmonary resuscitation (CPR) allows to better assess risks and benefits of ventilation. Ventilation is required to maintain gas exchange, particularly when CPR is prolonged. Nevertheless, conventional ventilation (bag mask or mechanical ventilation) may be harmful when excessive or when chest compressions are interrupted. In fact large tidal volume and/or rapid respiratory rate may adversely compromise hemodynamic effects of chest compressions. In this regard, international recommendations that give the priority to chest compressions, are meaningful. Continuous flow insufflation with oxygen that generates a moderate positive airway pressure avoids any interruption of chest compressions and prevents the risk of lung injury associated with prolonged resuscitation.

  20. [The choice of a pediatric anesthesia ventilator].

    PubMed

    Kern, D; Larcher, C; Cottron, N; Ait Aissa, D; Fesseau, R; Alacoque, X; Delort, F; Masquère, P; Agnès, E; Visnadi, G; Fourcade, O

    2013-12-01

    The technology of anesthesia ventilators has substantially progressed during last years. The choice of a pediatric anesthesia ventilator needs to be led by multiple parameters: requirement, technical (pneumatic performance, velocity of halogenated or oxygen delivery), cost (purchase, in operation, preventive and curative maintenance), reliability, ergonomy, upgradability, and compatibility. The demonstration of the interest of pressure support mode during maintenance of spontaneous ventilation anesthesia makes this mode essential in pediatrics. In contrast, the financial impact of target controlled inhalation of halogenated has not be studied in pediatrics. Paradoxically, complex and various available technologies had not been much prospectively studied. Anesthesia ventilators performances in pediatrics need to be clarified in further clinical and bench test studies.

  1. [Mechanical ventilation at home: facts and questions].

    PubMed

    Fitting, J W

    1993-06-15

    Treatment of respiratory insufficiency with retention of CO2 by mechanic ventilation has come into use over the last decade, favored by use of non-invasive methods like nasal ventilation. Best results have been observed in hypercapnic respiratory insufficiency caused by neuromuscular disease or restrictive pathologic changes of the lung. Nocturnal use of nasal ventilation alone is often sufficient to correct also the daily CO2-values. Mechanisms explaining this beneficial effect are not yet known-The respiratory CNS-centers, respiratory muscles or thoracopulmonary mechanics may play etiologically an important role. Medical indications for nasal ventilation in chronic obstructive pulmonary disease are not clear, since results from several studies are controversial. Also in severe or progressive neurologic diseases a critical evaluation is mandatory for assessment of benefits including improvement of quality of life.

  2. Innovative ventilation system for animal anatomy laboratory

    SciTech Connect

    Lacey, D.R.; Smith, D.C.

    1997-04-01

    A unique ventilation system was designed and built to reduce formaldehyde fumes in the large animal anatomy lab at the Vet Medical Center at Cornell University. The laboratory includes four rooms totaling 5,500 ft{sup 2}. The main room has 2,300 ft{sup 2} and houses the laboratory where up to 60 students dissect as many as 12 horses at a time. Other rooms are a cold storage locker, an animal preparation room and a smaller lab for specialized instruction. The large animal anatomy laboratory has a history of air quality complaints despite a fairly high ventilation rate of over 10 air changes/hour. The horses are embalmed, creating a voluminous source of formaldehyde and phenol vapors. Budget constraints and increasingly stringent exposure limits for formaldehyde presented a great challenge to design a ventilation system that yields acceptable air quality. The design solution included two innovative elements: air-to-air heat recovery, and focused ventilation.

  3. EVALUATION OF VENTILATION PERFORMANCE FOR INDOOR SPACE

    EPA Science Inventory

    The paper discusses a personal-computer-based application of computational fluid dynamics that can be used to determine the turbulent flow field and time-dependent/steady-state contaminant concentration distributions within isothermal indoor space. (NOTE: Ventilation performance ...

  4. Evaluating Ventilation Systems for Existing Homes

    SciTech Connect

    Aldrich, Robb; Arena, Lois

    2013-02-01

    In an effort to improve housing options near Las Vegas, Nevada, the Clark County Community Resources Division (CCCRD) performs substantial renovations to foreclosed homes. After dramatic energy, aesthetic, and health and safety improvements are made, homes are rented or sold to qualified residents. This report describes the evaluation and selection of ventilation systems for these homes, including key considerations when selecting an ideal system. The report then describes CCCRD’s decision process with respect to ventilation.

  5. Adequacy of Wind Ventilation in Upgraded Shelters.

    DTIC Science & Technology

    1980-05-01

    cross - sectional area. An approximate value of the "through-flow area" for the front door opening of model I can be calculated in the following way...Summary of Mathematical Models taken From References in Section 2 APPENDIX B - Ventilation Throughout Calculation Model GARD, INC. vii LIST OF FIGURES...as frequency of dooring opening, presence of fireplaces and chimneys , operation of ventilators and exhaust fans, furnace operation, etc. (Refs 2.10

  6. Mechanical Ventilation and ARDS in the ED

    PubMed Central

    Mohr, Nicholas M.; Miller, Christopher N.; Deitchman, Andrew R.; Castagno, Nicole; Hassebroek, Elizabeth C.; Dhedhi, Adam; Scott-Wittenborn, Nicholas; Grace, Edward; Lehew, Courtney; Kollef, Marin H.

    2015-01-01

    BACKGROUND: There are few data regarding mechanical ventilation and ARDS in the ED. This could be a vital arena for prevention and treatment. METHODS: This study was a multicenter, observational, prospective, cohort study aimed at analyzing ventilation practices in the ED. The primary outcome was the incidence of ARDS after admission. Multivariable logistic regression was used to determine the predictors of ARDS. RESULTS: We analyzed 219 patients receiving mechanical ventilation to assess ED ventilation practices. Median tidal volume was 7.6 mL/kg predicted body weight (PBW) (interquartile range, 6.9-8.9), with a range of 4.3 to 12.2 mL/kg PBW. Lung-protective ventilation was used in 122 patients (55.7%). The incidence of ARDS after admission from the ED was 14.7%, with a mean onset of 2.3 days. Progression to ARDS was associated with higher illness severity and intubation in the prehospital environment or transferring facility. Of the 15 patients with ARDS in the ED (6.8%), lung-protective ventilation was used in seven (46.7%). Patients who progressed to ARDS experienced greater duration in organ failure and ICU length of stay and higher mortality. CONCLUSIONS: Lung-protective ventilation is infrequent in patients receiving mechanical ventilation in the ED, regardless of ARDS status. Progression to ARDS is common after admission, occurs early, and worsens outcome. Patient- and treatment-related factors present in the ED are associated with ARDS. Given the limited treatment options for ARDS, and the early onset after admission from the ED, measures to prevent onset and to mitigate severity should be instituted in the ED. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01628523; URL: www.clinicaltrials.gov PMID:25742126

  7. Sensor-based demand controlled ventilation

    SciTech Connect

    De Almeida, A.T.; Fisk, W.J.

    1997-07-01

    In most buildings, occupancy and indoor pollutant emission rates vary with time. With sensor-based demand-controlled ventilation (SBDCV), the rate of ventilation (i.e., rate of outside air supply) also varies with time to compensate for the changes in pollutant generation. In other words, SBDCV involves the application of sensing, feedback and control to modulate ventilation. Compared to ventilation without feedback, SBDCV offers two potential advantages: (1) better control of indoor pollutant concentrations; and (2) lower energy use and peak energy demand. SBDCV has the potential to improve indoor air quality by increasing the rate of ventilation when indoor pollutant generation rates are high and occupants are present. SBDCV can also save energy by decreasing the rate of ventilation when indoor pollutant generation rates are low or occupants are absent. After providing background information on indoor air quality and ventilation, this report provides a relatively comprehensive discussion of SBDCV. Topics covered in the report include basic principles of SBDCV, sensor technologies, technologies for controlling air flow rates, case studies of SBDCV, application of SBDCV to laboratory buildings, and research needs. SBDCV appears to be an increasingly attractive technology option. Based on the review of literature and theoretical considerations, the application of SBDCV has the potential to be cost-effective in applications with the following characteristics: (a) a single or small number of dominant pollutants, so that ventilation sufficient to control the concentration of the dominant pollutants provides effective control of all other pollutants; (b) large buildings or rooms with unpredictable temporally variable occupancy or pollutant emission; and (c) climates with high heating or cooling loads or locations with expensive energy.

  8. Performance of Portable Ventilators at Temperature Extremes

    DTIC Science & Technology

    2015-03-30

    support of patients requires ventilators deliver desired settings accurately. Consistent tidal volume ( VT ) is of critical importance, especially in...low VT (6 mL/kg of predicted body weight) improved mortality [1]. Other ventilator settings such as respiratory rate and positive end expiratory...Delivered and set VTs were compared using the American Society for Testing and Materials (ASTM) standard of ±10% of set VT [4]. Table 1. Pediatric

  9. [High-frequency oscillatory ventilation in neonates].

    PubMed

    2002-09-01

    High-frequency oscillatory ventilation (HFOV) may be considered as an alternative in the management of severe neonatal respiratory failure requiring mechanical ventilation. In patients with diffuse pulmonary disease, HFOV can applied as a rescue therapy with a high lung volume strategy to obtain adequate alveolar recruitment. We review the mechanisms of gas exchange, as well as the indications, monitoring and special features of the use HVOF in the neonatal period.

  10. Pretest Predictions for Phase II Ventilation Tests

    SciTech Connect

    Yiming Sun

    2001-09-19

    The objective of this calculation is to predict the temperatures of the ventilating air, waste package surface, and concrete pipe walls that will be developed during the Phase II ventilation tests involving various test conditions. The results will be used as inputs to validating numerical approach for modeling continuous ventilation, and be used to support the repository subsurface design. The scope of the calculation is to identify the physical mechanisms and parameters related to thermal response in the Phase II ventilation tests, and describe numerical methods that are used to calculate the effects of continuous ventilation. The calculation is limited to thermal effect only. This engineering work activity is conducted in accordance with the ''Technical Work Plan for: Subsurface Performance Testing for License Application (LA) for Fiscal Year 2001'' (CRWMS M&O 2000d). This technical work plan (TWP) includes an AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities'', activity evaluation (CRWMS M&O 2000d, Addendum A) that has determined this activity is subject to the YMP quality assurance (QA) program. The calculation is developed in accordance with the AP-3.12Q procedure, ''Calculations''. Additional background information regarding this activity is contained in the ''Development Plan for Ventilation Pretest Predictive Calculation'' (DP) (CRWMS M&O 2000a).

  11. [Ventilator-associated pneumonia and other infections].

    PubMed

    Bobik, Piotr; Siemiątkowski, Andrzej

    2014-01-01

    One of the fundamental elements of therapy in patients hospitalised in the Intensive Care Unit (ICU) is mechanical ventilation (MV). MV enables sufficient gas exchange in patients with severe respiratory insufficiency, thus preserving the proper functioning of organs and systems. However, clinical and experimental studies show that mechanical ventilation may cause severe complications, e.g. lung injury (VALI, VILI), systemic inflammatory response syndrome (SIRS), and, on rare occasions, multiple organ failure (MOF). Mechanical ventilation and especially endotracheal intubation are associated also with higher risk of infectious complications of the respiratory system: ventilator-associated respiratory infection (VARI) and ventilator-associated pneumonia (VAP). The complications of the MV listed above have a significant influence on the length of treatment and also on the increase of the costs of therapy and mortality of patients who stay in an ICU. These negative effects of supported breathing are the reasons for intensive research to find new biological markers of inflammation and lung injury, more sensitive and specific diagnostic instruments, more effective methods of therapy, and programs of prevention. The purpose of this article is the presentation of current knowledge concerning VAP-related infections, to allow pulmonologists and general practitioners to become more familiar with the problem. Basic and the most important data concerning the definition, epidemiology, pathophysiology, microbiology, diagnostics, treatment, and prevention of VAP have been included. Additionally, ventilator-associated tracheobronchitis (VAT) was discussed.

  12. Clinical review: Long-term noninvasive ventilation

    PubMed Central

    Robert, Dominique; Argaud, Laurent

    2007-01-01

    Noninvasive positive ventilation has undergone a remarkable evolution over the past decades and is assuming an important role in the management of both acute and chronic respiratory failure. Long-term ventilatory support should be considered a standard of care to treat selected patients following an intensive care unit (ICU) stay. In this setting, appropriate use of noninvasive ventilation can be expected to improve patient outcomes, reduce ICU admission, enhance patient comfort, and increase the efficiency of health care resource utilization. Current literature indicates that noninvasive ventilation improves and stabilizes the clinical course of many patients with chronic ventilatory failure. Noninvasive ventilation also permits long-term mechanical ventilation to be an acceptable option for patients who otherwise would not have been treated if tracheostomy were the only alternative. Nevertheless, these results appear to be better in patients with neuromuscular/-parietal disorders than in chronic obstructive pulmonary disease. This clinical review will address the use of noninvasive ventilation (not including continuous positive airway pressure) mainly in diseases responsible for chronic hypoventilation (that is, restrictive disorders, including neuromuscular disease and lung disease) and incidentally in others such as obstructive sleep apnea or problems of central drive. PMID:17419882

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

    PubMed Central

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

    2016-01-01

    Background and Aims: 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. Material and Methods: 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. Results: 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. Conclusion: Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients. PMID:27625477

  14. [Effects of body mass index on blood pressure control rate in elderly coronary heart disease outpatients with hypertension].

    PubMed

    Liang, D L; Li, X Y; Wang, L; Xu, H; Tuo, X P; Jian, Z J

    2016-09-20

    Objective: To explore the influences of body mass index (BMI) on blood pressure control rate in elderly coronary heart disease (CHD) outpatients with hypertension. Methods: In this multicenter, non-intervention and cross-sectional survey, the elderly coronary heart disease patients with hypertension aged 60 years or over were recruited from 165 hospitals in 21 provinces or cities across China from April to July 2011, and 5 140 cases of elderly CHD patients with hypertension were finally included into the study. The cases were divided into low BMI group (n=130 cases), normal body mass index (BMI) group (n=1 390 cases), overweight (n=2 418 cases), obesity group (n=662 cases) according to the different levels of BMI. Clinical data and blood pressure control rate were compared among the groups, and relationships of different BMI levels with blood pressure control rate were analyzed by the binary classification unconditioned Logistic regression equation. Results: There was a statistically significant difference in blood pressure control rate of general population, men and women patients among low BMI group, normal BMI group, overweight and obesity group (χ(2)=66.346, 58.995, 26.044, respectively, P<0.001), blood pressure failure rate in obesity group (73.7%) was higher than that in overweight group (65.8%) and normal BMI group (57.5%) (P<0.05), and overweight group was also higher than normal BMI group (P<0.05); blood pressure failure rate in obesity men was higher than that in normal BMI and low BMI group (P<0.05), overweight group was higher than normal BMI group (P<0.05); blood pressure failure rate in obesity women was higher than that in normal BMI and low BMI group (P<0.05). There was a statistically significant difference in blood pressure control rate of different age groups (60-70, 71-80, >80 years old) among low BMI group, normal BMI group, overweight and obesity group (χ(2)=37.729, 20.007, 15.538, respectively, P<0.001). Blood pressure failure rate in

  15. Estimation of spontaneous baroreflex sensitivity using transfer function analysis: effects of positive pressure ventilation.

    PubMed

    Glos, Martin; Romberg, Dietrich; Endres, Susanne; Fietze, Ingo

    2007-02-01

    To determine the short-term effects of non-invasive positive pressure ventilation (PPV) on spontaneous baroreflex sensitivity, we acquired time series of RR interval and beat-to-beat blood pressure in 55 healthy volunteers (mean age 46.5+/-10.5 years), who performed breathing tests on four occasions at frequencies of 12 and 15/min, with application of PPV of 5 mbar, and without positive pressure (control). Using spectral and transfer function analysis, we estimated RR interval variability (HRV) and systolic blood pressure variability (SBPV), as well as the gain (alpha-index) and phase shift (Phi) of the baroreceptor reflex for low- (LF) and high-frequency (HF) bands. Compared to control breathing, PPV at 12 and 15/min led to an increase in mean RR (p<0.001) and blood pressure (p<0.05). The alpha-index in the HF band increased significantly due to PPV for both respiratory frequencies (p<0.05). Phase shifts did not show significant changes in response to pressure ventilation. These results indicate that short-term administration of PPV in normal subjects elicits significant enhancement in the HF index of baroreflex gain. These findings may contribute to understanding the mechanisms, indications, and effectiveness of positive pressure breathing strategies in treating cardiorespiratory and other disease conditions.

  16. 41 CFR 102-74.195 - What ventilation policy must Federal agencies follow?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... provide ventilation in accordance with ASHRAE Standard 62, Ventilation for Acceptable Indoor Air Quality... ventilation up to current standards. ASHRAE Standard 62 is available from ASHRAE Publications Sales,...

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

    PubMed

    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. Pneumatic displacement and intra-vitreal bevacizumab in management of sub-retinal and sub-retinal pigment epithelial hemorrhage at macula in polypoidal choroidal vasculopathy (PCV): rationale and outcome.

    PubMed

    Nayak, Sameera; Padhi, Tapas Ranjan; Basu, Soumyava; Das, Taraprasad

    2015-01-01

    We report three cases of submacular haemorrhage due to polypoidal choroidal vasculopathy (PCV) treated with intravitreal bevacizumab and pneumatic displacement with perfluoropropane (C3F8) gas. The patients were between 45 to 55 years and presented with reduction of vision (20/400 to 20/80) within two weeks of onset of symptoms. The submacular (sub-retinal plus sub-retinal pigment epithelium [RPE]) hemorrhages was confirmed as PCV on indocyanine green angiography and optical coherence tomography in all of them. They were treated with intravitreal bevacizumab (1.25 mg/0.05 ml) and 0.3 ml of 100% C3F8 gas in the affected eye followed by prone positioning for two weeks. The vision and macular anatomy started improving within a week and continued up to three months. These cases demonstrate that pneumatic displacement combined with intravitreal anti-VEGF injection could be a promising option in patients with PCV and sub-macular blood, even when the blood is beneath the RPE.

  19. Anesthesia and critical care ventilator modes: past, present, and future.

    PubMed

    Bristle, Timothy J; Collins, Shawn; Hewer, Ian; Hollifield, Kevin

    2014-10-01

    Mechanical ventilators have evolved from basic machines to complicated, electronic, microprocessing engines. Over the last 2 decades, ventilator capabilities and options for critical care and anesthesia ventilators have rapidly advanced. These advances in ventilator modalities--in conjunction with a better understanding of patient physiology and the effects of positive pressure ventilation on the body--have revolutionized the mechanical ventilation process. Clinicians today have a vast array of mechanical ventilator mode options designed to match the pulmonary needs of the critically ill and anesthetized patient. Modes of mechanical ventilation continue to be based on 1 of 2 variances: volume-based or pressure-based. The wording describing the standard ventilatory modes on select present-day ventilators has changed, yet the basic principles of operation have not changed compared with older ventilators. Anesthesia providers need to understand these ventilator modes to best care for patients. This literature review encompasses a brief history of mechanical ventilation and current modes available for anesthesia and critical care ventilators, including definitions of each mode, definitions of the various descriptive labels given each mode, and techniques for optimizing and meeting the ventilator needs of the patient while avoiding complications in the surgical and critical care patient.

  20. Carbon-dioxide-controlled ventilation study

    SciTech Connect

    McMordie, K.L.; Carroll, D.M.

    1994-05-01

    The In-House Energy Management (IHEM) Program has been established by the U.S. Department of Energy to provide funds to federal laboratories to conduct research on energy-efficient technology. The Energy Sciences Department of Pacific Northwest Laboratory (PNL) was tasked by IHEM to research the energy savings potential associated with reducing outdoor-air ventilation of buildings. By monitoring carbon dioxide (CO{sub 2}) levels in a building, outdoor air provided by the heating, ventilating, and air-conditioning (HVAC) system can be reduced to the percentage required to maintain satisfactory CO{sub 2} levels rather than ventilating with a higher outdoor-air percentage based on an arbitrary minimum outdoor-air setting. During summer months, warm outdoor air brought into a building for ventilation must be cooled to meet the appropriate cooling supply-air temperature, and during winter months, cold outdoor air must be heated. By minimizing the amount of hot or cold outdoor air brought into the HVAC system, the supply air requires less cooling or heating, saving energy and money. Additionally, the CO{sub 2} levels in a building can be monitored to ensure that adequate outdoor air is supplied to a building to maintain air quality levels. The two main considerations prior to implementing CO{sub 2}-based ventilation control are its impact on energy consumption and the adequacy of indoor air quality (IAQ) and occupant comfort. To address these considerations, six portable CO{sub 2} monitors were placed in several Hanford Site buildings to estimate the adequacy of office/workspace ventilation. The monitors assessed the potential for reducing the flow of outdoor-air to the buildings. A candidate building was also identified to monitor various ventilation control strategies for use in developing a plan for implementing and assessing energy savings.

  1. Regenerative Blower for EVA Suit Ventilation Fan

    NASA Technical Reports Server (NTRS)

    Izenson, Michael G.; Chen, Weibo; Paul, Heather L.

    2010-01-01

    Portable life support systems in future space suits will include a ventilation subsystem driven by a dedicated fan. This ventilation fan must meet challenging requirements for pressure rise, flow rate, efficiency, size, safety, and reliability. This paper describes research and development that showed the feasibility of a regenerative blower that is uniquely suited to meet these requirements. We proved feasibility through component tests, blower tests, and design analysis. Based on the requirements for the Constellation Space Suit Element (CSSE) Portable Life Support System (PLSS) ventilation fan, we designed the critical elements of the blower. We measured the effects of key design parameters on blower performance using separate effects tests, and used the results of these tests to design a regenerative blower that will meet the ventilation fan requirements. We assembled a proof-of-concept blower and measured its performance at sub-atmospheric pressures that simulate a PLSS ventilation loop environment. Head/flow performance and maximum efficiency point data were used to specify the design and operating conditions for the ventilation fan. We identified materials for the blower that will enhance safety for operation in a lunar environment, and produced a solid model that illustrates the final design. The proof-of-concept blower produced the flow rate and pressure rise needed for the CSSE ventilation subsystem while running at 5400 rpm, consuming only 9 W of electric power using a non-optimized, commercial motor and controller and inefficient bearings. Scaling the test results to a complete design shows that a lightweight, compact, reliable, and low power regenerative blower can meet the performance requirements for future space suit life support systems.

  2. Ventilation efficiencies of a desk-edge-mounted task ventilation system

    SciTech Connect

    Faulkner, David; Fisk, William J.; Sullivan, Douglas P.; Lee, Seung Min

    2002-03-01

    In chamber experiments, we investigated the effectiveness of a task ventilation system with an air supply nozzle located underneath the front edge of a desk and directing air toward a heated mannequin seated at the desk. The task ventilation system provided outside air, while another ventilation system provided additional space cooling but no outside air. Test variables included the vertical angle of air supply (-15{sup o} to 45{sup o} from horizontal), and the supply flow rate of (3.5 to 6.5 L s{sup -1}). Using the tracer gas step-up and step-down procedures, the measured air change effectiveness (i.e., exhaust air age divided by age of air at the mannequin's face) ranged from 1.4 to 2.7, which is higher than typically reported for commercially available task ventilation or displacement ventilation systems.

  3. Hydrostatic Hyperbaric Chamber Ventilation System

    NASA Technical Reports Server (NTRS)

    Sargusingh, Miriam M.

    2011-01-01

    The hydrostatic hyperbaric chamber (HHC) represents the merger of several technologies in development for NASA aerospace applications, harnessed to directly benefit global health. NASA has significant experience developing composite hyperbaric chambers for a variety of applications, including the treatment of medical conditions. NASA also has researched the application of water-filled vessels to increase tolerance of acceleration forces. The combination of these two applications has resulted in the hydrostatic chamber, which has been conceived as a safe, affordable means of making hyperbaric oxygen therapy available in the developing world for the treatment of a variety of medical conditions. Specifically, hyperbaric oxygen therapy is highly-desired as a possibly curative treatment for Buruli Ulcer, an infectious condition that afflicts children in sub-Saharan Africa. Hyperbaric oxygen therapy is simply too expensive and too dangerous to implement in the developing world using standard equipment. The hydrostatic hyperbaric chamber technology changes the paradigm. The HHC differs from standard hyperbaric chambers in that the majority of its volume is filled with water which is pressurized by oxygen being supplied in the portion of the chamber containing the patient s head. This greatly reduces the amount of oxygen required to sustain a hyperbaric atmosphere, thereby making the system more safe and economical to operate. An effort was taken to develop an HHC system to apply HBOT to children that is simple and robust enough to support transport, assembly, maintenance and operation in developing countries. This paper details the concept for an HHC ventilation and pressurization system that will provide controlled pressurization of the system, and provide adequate washout of carbon dioxide while the subject is enclosed in the confined space during the administration of the medical treatment. The concept took into consideration operational complexity, safety to the

  4. Hydrostatic Hyperbaric Chamber Ventilation System

    NASA Technical Reports Server (NTRS)

    Sarguisingh, Miriam J.

    2012-01-01

    The hydrostatic hyperbaric chamber (HHC) represents the merger of several technologies in development for NASA aerospace applications, harnessed to directly benefit global health. NASA has significant experience developing composite hyperbaric chambers for a variety of applications. NASA also has researched the application of water-filled vessels to increase tolerance of acceleration forces. The combination of these two applications has resulted in the hydrostatic chamber, which has been conceived as a safe, affordable means of making hyperbaric oxygen therapy (HBOT) available in the developing world for the treatment of a variety of medical conditions. Specifically, HBOT is highly-desired as a possibly curative treatment for Buruli Ulcer, an infectious condition that afflicts children in sub-Saharan Africa. HBOT is simply too expensive and too dangerous to implement in the developing world using standard equipment. The HHC technology changes the paradigm. The HHC differs from standard hyperbaric chambers in that the majority of its volume is filled with water which is pressurized by oxygen being supplied in the portion of the chamber containing the patient s head. This greatly reduces the amount of oxygen required to sustain a hyperbaric atmosphere, thereby making the system more safe and economical to operate. An effort was taken to develop an HHC system to apply HBOT to children that is simple and robust enough to support transport, assembly, maintenance and operation in developing countries. This paper details the concept for an HHC ventilation and pressurization system to provide controlled pressurization and adequate washout of carbon dioxide while the subject is enclosed in the confined space during the administration of the medical treatment. The concept took into consideration operational complexity, safety to the patient and operating personnel, and physiological considerations. The simple schematic, comprised of easily acquired commercial hardware

  5. Engineering work plan and design basis for 241-SY ventilation improvements

    SciTech Connect

    Andersen, J.A.

    1997-05-19

    There are three tanks in the 241-SY tank farm. Tank 241-SY101 and 241-SY-103 are flammable gas watch list tanks. Tank 241-SY-102 is included in the ventilation improvement process in an effort to further control air flow in the tank farm. This tank farm has only one outlet ventilation port for all three tanks. Flammable gas is released (may be steady and/or periodic) from the waste in the primary tank vapor space. The gas is removed from the tank by an active ventilation system. However, maintaining consistent measurable flow through the tank can be problematic due to the poor control capabilities of existing equipment. Low flow through the tank could allow flammable gas to build up in the tank and possibly exceed the lower flammability limit (LFL), prevent the most rapid removal of flammable gas from the tank after a sudden gas release, and/or cause high vacuum alarms to sound. Using the inlet and outlet down stream butterfly valves performs the current method of controlling flow in tank farm 241-SY. A filter station is installed on the inlet of each tank, but controlling air flow with its 12 inch butterfly valve is difficult. There is also in-leakage through pump and valve pits. Butterfly valves on the downstream side of each tank could also be used to control air flow. However, their large size and the relatively low air velocity make this control method also ineffective. The proposed method of optimizing tank air flow and pressure control capability is to install an air flow controller on the inlet of each existing filter station in SY farm, and seal as best as practical all other air leakage paths. Such air flow controllers have been installed on 241-AN and 241-AW tanks (see drawing H-2-85647).

  6. A Porcine Model for Initial Surge Mechanical Ventilator Assessment and Evaluation of Two Limited Function Ventilators

    PubMed Central

    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

  7. Effect of interfacial turbulence and accommodation coefficient on CFD predictions of pressurization and pressure control in cryogenic storage tank

    NASA Astrophysics Data System (ADS)

    Kassemi, Mohammad; Kartuzova, Olga

    2016-03-01

    Pressurization and pressure control in cryogenic storage tanks are to a large extent affected by heat and mass transport across the liquid-vapor interface. These mechanisms are, in turn, controlled by the kinetics of the phase change process and the dynamics of the turbulent recirculating flows in the liquid and vapor phases. In this paper, the effects of accommodation coefficient and interfacial turbulence on tank pressurization and pressure control simulations are examined. Comparison between numerical predictions and ground-based measurements in two large liquid hydrogen tank experiments, performed in the K-site facility at NASA Glenn Research Center (GRC) and the Multi-purpose Hydrogen Test Bed (MHTB) facility at NASA Marshall Space Flight Center (MSFC), are used to show the impact of accommodation coefficient and interfacial and vapor phase turbulence on evolution of pressure and temperatures in the cryogenic storage tanks. In particular, the self-pressurization comparisons indicate that: (1) numerical predictions are essentially independent of the magnitude of the accommodation coefficient; and (2) surprisingly, laminar models sometimes provide results that are in better agreement with experimental self-pressurization rates, even in parametric ranges where the bulk flow is deemed fully turbulent. In this light, shortcomings of the present CFD models, especially, numerical treatments of interfacial mass transfer and turbulence, as coupled to the Volume-of-Fluid (VOF) interface capturing scheme, are underscored and discussed.

  8. A novel osmotic pressure control fed-batch fermentation strategy for improvement of erythritol production by Yarrowia lipolytica from glycerol.

    PubMed

    Yang, Li-Bo; Zhan, Xiao-Bei; Zheng, Zhi-Yong; Wu, Jian-Rong; Gao, Min-Jie; Lin, Chi-Chung

    2014-01-01

    The effect of osmotic pressure on erythritol and mannitol production by an osmophilic yeast strain of Yarrowia lipolytica CICC 1675 using glycerol as the sole carbon source was investigated. Appropriately high osmotic pressure was found to enhance erythritol production and inhibit mannitol formation. A novel two-stage osmotic pressure control fed-batch strategy based on the kinetic analysis was developed for higher erythritol yield and productivity. During the first 96 h, the osmotic pressure was maintained at 4.25 osmol/kg by feeding glycerol to reduce the inhibition of cell growth. After 132 h, the osmotic pressure was controlled at 4.94 osmol/kg to maintain a high dp(ery)/dt. Maximum erythritol yield of 194.3g/L was obtained with 0.95 g/L/h productivity, which were 25.7% and 2.2%, respectively, improvement over the best results in one-stage fed-batch fermentation. This is the first report that a novel osmotic pressure control fed-batch strategy significantly enhanced erythritol production.

  9. Large-scale self-assembly of uniform submicron silver sulfide material driven by precise pressure control.

    PubMed

    Qi, Juanjuan; Chen, Ke; Zhang, Shuhao; Yang, Yun; Guo, Lin; Yang, Shihe

    2017-03-10

    The controllable self-assembly of nanosized building blocks into larger specific structures can provide an efficient method of synthesizing novel materials with excellent properties. The self-assembly of nanocrystals by assisted means is becoming an extremely active area of research, because it provides a method of producing large-scale advanced functional materials with potential applications in the areas of energy, electronics, optics, and biologics. In this study, we applied an efficient strategy, namely, the use of 'pressure control' to the assembly of silver sulfide (Ag2S) nanospheres  with a diameter of approximately 33 nm into large-scale, uniform Ag2S sub-microspheres with a size of about 0.33 μm. More importantly, this strategy realizes the online control of the overall reaction system, including the pressure, reaction time, and temperature, and could also be used to easily fabricate other functional materials on an industrial scale. Moreover, the thermodynamics and kinetics parameters for the thermal decomposition of silver diethyldithiocarbamate (Ag(DDTC)) are also investigated to explore the formation mechanism of the Ag2S nanosized building blocks which can be assembled into uniform sub-micron scale architecture. As a method of producing sub-micron Ag2S particles by means of the pressure-controlled self-assembly of nanoparticles, we foresee this strategy being an efficient and universally applicable option for constructing other new building blocks and assembling novel and large functional micromaterials on an industrial scale.

  10. WASTE HANDLING BUILDING VENTILATION SYSTEM DESCRIPTION DOCUMENT

    SciTech Connect

    P.A. Kumar

    2000-06-21

    The Waste Handling Building Ventilation System provides heating, ventilation, and air conditioning (HVAC) for the contaminated, potentially contaminated, and uncontaminated areas of the Monitored Geologic Repository's (MGR) Waste Handling Building (WHB). In the uncontaminated areas, the non-confinement area ventilation system maintains the proper environmental conditions for equipment operation and personnel comfort. In the contaminated and potentially contaminated areas, in addition to maintaining the proper environmental conditions for equipment operation and personnel comfort, the contamination confinement area ventilation system directs potentially contaminated air away from personnel in the WHB and confines the contamination within high-efficiency particulate air (HEPA) filtration units. The contamination confinement areas ventilation system creates airflow paths and pressure zones to minimize the potential for spreading contamination within the building. The contamination confinement ventilation system also protects the environment and the public by limiting airborne releases of radioactive or other hazardous contaminants from the WHB. The Waste Handling Building Ventilation System is designed to perform its safety functions under accident conditions and other Design Basis Events (DBEs) (such as earthquakes, tornadoes, fires, and loss of the primary electric power). Additional system design features (such as compartmentalization with independent subsystems) limit the potential for cross-contamination within the WHB. The system provides status of important system parameters and equipment operation, and provides audible and/or visual indication of off-normal conditions and equipment failures. The Waste Handling Building Ventilation System confines the radioactive and hazardous material within the building such that the release rates comply with regulatory limits. The system design, operations, and maintenance activities incorporate ALARA (as low as is

  11. Tunnel Ventilation Control Using Reinforcement Learning Methodology

    NASA Astrophysics Data System (ADS)

    Chu, Baeksuk; Kim, Dongnam; Hong, Daehie; Park, Jooyoung; Chung, Jin Taek; Kim, Tae-Hyung

    The main purpose of tunnel ventilation system is to maintain CO pollutant concentration and VI (visibility index) under an adequate level to provide drivers with comfortable and safe driving environment. Moreover, it is necessary to minimize power consumption used to operate ventilation system. To achieve the objectives, the control algorithm used in this research is reinforcement learning (RL) method. RL is a goal-directed learning of a mapping from situations to actions without relying on exemplary supervision or complete models of the environment. The goal of RL is to maximize a reward which is an evaluative feedback from the environment. In the process of constructing the reward of the tunnel ventilation system, two objectives listed above are included, that is, maintaining an adequate level of pollutants and minimizing power consumption. RL algorithm based on actor-critic architecture and gradient-following algorithm is adopted to the tunnel ventilation system. The simulations results performed with real data collected from existing tunnel ventilation system and real experimental verification are provided in this paper. It is confirmed that with the suggested controller, the pollutant level inside the tunnel was well maintained under allowable limit and the performance of energy consumption was improved compared to conventional control scheme.

  12. Ventilator associated pneumonia in major paediatric burns.

    PubMed

    Rogers, Alan David; Deal, Cailin; Argent, Andrew Charles; Hudson, Donald Anthony; Rode, Heinz

    2014-09-01

    More than three-quarters of deaths related to major burns are a consequence of infection, which is frequently ventilator associated pneumonia (VAP). A retrospective study was performed, over a five-year period, of ventilated children with major burns. 92 patients were included in the study; their mean age was 3.5 years and their mean total body surface area burn was 30%. 62% of the patients sustained flame burns, and 31% scalds. The mean ICU stay was 10.6 days (range 2-61 days) and the mean ventilation time was 8.4 days (range 2-45 days). There were 59 documented episodes of pneumonia in 52 patients with a rate of 30 infections per 1000 ventilator days. Length of ventilation and the presence of inhalational injury correlate with the incidence of VAP. 17.4% of the patients died (n=16); half of these deaths may be attributed directly to pneumonia. Streptococcus pneumonia, Pseudomonas aeruginosa, Acinetobacter baumanii and Staphylococcus aureus were the most prominent aetiological organisms. Broncho-alveolar lavage was found to be more specific and sensitive at identifying the organism than other methods. This study highlights the importance of implementing strictly enforced strategies for the prevention, detection and management of pneumonia in the presence of major burns.

  13. Dynamic behavior during noninvasive ventilation: chaotic support?

    PubMed

    Hotchkiss, J R; Adams, A B; Dries, D J; Marini, J J; Crooke, P S

    2001-02-01

    Acute noninvasive ventilation is generally applied via face mask, with modified pressure support used as the initial mode to assist ventilation. Although an adequate seal can usually be obtained, leaks frequently develop between the mask and the patient's face. This leakage presents a theoretical problem, since the inspiratory phase of pressure support terminates when flow falls to a predetermined fraction of peak inspiratory flow. To explore the issue of mask leakage and machine performance, we used a mathematical model to investigate the dynamic behavior of pressure-supported noninvasive ventilation, and confirmed the predicted behavior through use of a test lung. Our mathematical and laboratory analyses indicate that even when subject effort is unvarying, pressure-support ventilation applied in the presence of an inspiratory leak proximal to the airway opening can be accompanied by marked variations in duration of the inspiratory phase and in autoPEEP. The unstable behavior was observed in the simplest plausible mathematical models, and occurred at impedance values and ventilator settings that are clinically realistic.

  14. Mechanical Ventilation in Sepsis: A Reappraisal.

    PubMed

    Zampieri, Fernando G; Mazza, Bruno

    2017-01-01

    Sepsis is the main cause of close to 70% of all cases of acute respiratory distress syndromes (ARDS). In addition, sepsis increases susceptibility to ventilator-induced lung injury. Therefore, the development of a ventilatory strategy that can achieve adequate oxygenation without injuring the lungs is highly sought after for patients with acute infection and represents an important therapeutic window to improve patient care. Suboptimal ventilatory settings cannot only harm the lung, but may also contribute to the cascade of organ failure in sepsis due to organ crosstalk.Despite the prominent role of sepsis as a cause for lung injury, most of the studies that addressed mechanical ventilation strategies in ARDS did not specifically assess sepsis-related ARDS patients. Consequently, most of the recommendations regarding mechanical ventilation in sepsis patients are derived from ARDS trials that included multiple clinical diagnoses. While there have been important improvements in general ventilatory management that should apply to all critically ill patients, sepsis-related lung injury might still have particularities that could influence bedside management.After revisiting the interplay between sepsis and ventilation-induced lung injury, this review will reappraise the evidence for the major components of the lung protective ventilation strategy, emphasizing the particularities of sepsis-related acute lung injury.

  15. Design Feature 7: Continuous Preclosure Ventilation

    SciTech Connect

    A.T. Watkins

    1999-06-22

    This design feature (DF) is intended to evaluate the effects of continuous ventilation in the emplacement drifts during preclosure and how the effects, if any, compare to the Viability Assessment (VA) reference design for postclosure long term performance. This DF will be evaluated against a set of criteria provided by the License Application Design Selection (LADS) group. The VA reference design included a continuous ventilation airflow quantity of 0.1 m{sup 3}/s in the emplacement drifts in the design of the repository subsurface facilities. The effects of this continuous ventilation during the preclosure was considered to have a negligible effect on postclosure performance and therefore is not included during postclosure in the assessment of the long term performance. This DF discusses the effects of continuous ventilation on the emplacement drift environment and surrounding rock conditions during preclosure for three increased airflow quantities. The three cases of continuous ventilation systems are: System A, 1.0 m{sup 3}/s (Section 8), System B, 5.0 m{sup 3}/s (Section 9), and System C, 10.0 m{sup 3}/s (Section 10) in each emplacement drift split. An emplacement drift split is half total length of emplacement drift going from the east or west main to the exhaust main. The difference in each system is the quantity of airflow in the emplacement drifts.

  16. Cost-effectiveness analysis of routine pneumococcal vaccination in the UK: a comparison of the PHiD-CV vaccine and the PCV-13 vaccine using a Markov model

    PubMed Central

    Delgleize, Emmanuelle; Leeuwenkamp, Oscar; Theodorou, Eleni; Van de Velde, Nicolas

    2016-01-01

    Objectives In 2010, the 13-valent pneumococcal conjugate vaccine (PCV-13) replaced the 7-valent vaccine (introduced in 2006) for vaccination against invasive pneumococcal diseases (IPDs), pneumonia and acute otitis media (AOM) in the UK. Using recent evidence on the impact of PCVs and epidemiological changes in the UK, we performed a cost-effectiveness analysis (CEA) to compare the pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) with PCV-13 in the ongoing national vaccination programme. Design CEA was based on a published Markov model. The base-case scenario accounted only for direct medical costs. Work days lost were considered in alternative scenarios. Setting Calculations were based on serotype and disease-specific vaccine efficacies, serotype distributions and UK incidence rates and medical costs. Population Health benefits and costs related to IPD, pneumonia and AOM were accumulated over the lifetime of a UK birth cohort. Interventions Vaccination of infants at 2, 4 and 12 months with PHiD-CV or PCV-13, assuming complete coverage and adherence. Outcome measures The incremental cost-effectiveness ratio (ICER) was computed by dividing the difference in costs between the programmes by the difference in quality-adjusted life-years (QALY). Results Under our model assumptions, both vaccines had a similar impact on IPD and pneumonia, but PHiD-CV generated a greater reduction in AOM cases (161 918), AOM-related general practitioner consultations (31 070) and tympanostomy tube placements (2399). At price parity, PHiD-CV vaccination was dominant over PCV-13, saving 734 QALYs as well as £3.68 million to the National Health Service (NHS). At the lower list price of PHiD-CV, the cost-savings would increase to £45.77 million. Conclusions This model projected that PHiD-CV would provide both incremental health benefits and cost-savings compared with PCV-13 at price parity. Using PHiD-CV could result in substantial budget savings

  17. Flow measurement in mechanical ventilation: a review.

    PubMed

    Schena, Emiliano; Massaroni, Carlo; Saccomandi, Paola; Cecchini, Stefano

    2015-03-01

    Accurate monitoring of flow rate and volume exchanges is essential to minimize ventilator-induced lung injury. Mechanical ventilators employ flowmeters to estimate the amount of gases delivered to patients and use the flow signal as a feedback to adjust the desired amount of gas to be delivered. Since flowmeters play a crucial role in this field, they are required to fulfill strict criteria in terms of dynamic and static characteristics. Therefore, mechanical ventilators are equipped with only the following kinds of flowmeters: linear pneumotachographs, fixed and variable orifice meters, hot wire anemometers, and ultrasonic flowmeters. This paper provides an overview of these sensors. Their working principles are described together with their relevant advantages and disadvantages. Furthermore, the most promising emerging approaches for flowmeters design (i.e., fiber optic technology and three dimensional micro-fabrication) are briefly reviewed showing their potential for this application.

  18. MODELING VENTILATION SYSTEM RESPONSE TO FIRE

    SciTech Connect

    Coutts, D

    2007-04-17

    Fires in facilities containing nuclear material have the potential to transport radioactive contamination throughout buildings and may lead to widespread downwind dispersal threatening both worker and public safety. Development and implementation of control strategies capable of providing adequate protection from fire requires realistic characterization of ventilation system response which, in turn, depends on an understanding of fire development timing and suppression system response. This paper discusses work in which published HEPA filter data was combined with CFAST fire modeling predictions to evaluate protective control strategies for a hypothetical DOE non-reactor nuclear facility. The purpose of this effort was to evaluate when safety significant active ventilation coupled with safety class passive ventilation might be a viable control strategy.

  19. Prevention of ventilator-associated pneumonia.

    PubMed

    Oliveira, J; Zagalo, C; Cavaco-Silva, P

    2014-01-01

    Invasive mechanical ventilation (IMV) represents a risk factor for the development of ventilator-associated pneumonia (VAP), which develops at least 48h 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.

  20. Home Mechanical Ventilation in South Korea

    PubMed Central

    Kim, Dong Hyun; Choi, Won Ah

    2014-01-01

    Purpose To survey the use of invasive and noninvasive home mechanical ventilation (HMV) methods in South Korea from the perspective of physical medicine and rehabilitation (PM&R). Materials and Methods For 413 users of HMV, retrospective reviews of PM&R interventions and survey of HMV methods employed from Mar 2000 to Dec 2009. Results Of the 413 users, the majority of whom with progressive neuromuscular disorders (NMDs) (n=358), 284 patients initially used noninvasive mechanical ventilation (NIV), while 63 others who were using tracheostomy mechanical ventilation switched to NIV as part of their rehabilitation. The NMD patients began HMV at an earlier age (34.9±20.3 yrs), and used for longer (14.7±7.5) hours than patients with non-neuromuscular causes of respiratory impairment. Conclusion Noninvasive management was preferred over invasive ones, and transition to the former was a result of PM&R interventions. PMID:25323913

  1. Building ventilation and indoor air quality

    SciTech Connect

    Hollowell, C.D.; Berk, J.V.; Boegel, M.L.; Miksch, R.R.; Nazaroff, W.W.; Traynor, G.W.

    1980-01-01

    Rising energy prices, among other factors, have generated an incentive to reduce ventilation rates and thereby reduce the cost of heating and cooling buildings. Reduced infiltration and ventilation in buildings may significantly increase exposure to indoor contaminants and perhaps have adverse effects on occupant health and comfort. Four indoor air contaminants - carbon monoxide and nitrogen dioxide from gas appliances; formaldehyde from particleboard, plywood, urea-formaldehyde foam insulation, and gas appliances; and radon from building materials, soil, and ground water - are currently receiving considerable attention in the context of potential health risks associated with reduced infiltration and ventilation rates. These air contaminants in conventional and energy efficient buildings were measured and analyzed with a view to assessing their potential health risks and various control strategies capable of lowering pollutant concentrations. Preliminary findings suggest that further intensive studies are needed in order to develop criteria for maintaining acceptable indoor air quality without compromising energy efficiency.

  2. Open circuit mouthpiece ventilation: Concise clinical review.

    PubMed

    Garuti, G; Nicolini, A; Grecchi, B; Lusuardi, M; Winck, J C; Bach, J R

    2014-01-01

    In 2013 new "mouthpiece ventilation" modes are being introduced to commercially available portable ventilators. Despite this, there is little knowledge of how to use noninvasive intermittent positive pressure ventilation (NIV) as opposed to bi-level positive airway pressure (PAP) and both have almost exclusively been reported to have been used via nasal or oro-nasal interfaces rather than via a simple mouthpiece. Non-invasive ventilation is often reported as failing because of airway secretion encumbrance, because of hypercapnia due to inadequate bi-level PAP settings, or poor interface tolerance. The latter can be caused by factors such as excessive pressure on the face from poor fit, excessive oral air leak, anxiety, claustrophobia, and patient-ventilator dys-synchrony. Thus, the interface plays a crucial role in tolerance and effectiveness. Interfaces that cover the nose and/or nose and mouth (oro-nasal) are the most commonly used but are more likely to cause skin breakdown and claustrophobia. Most associated drawbacks can be avoided by using mouthpiece NIV. Open-circuit mouthpiece NIV is being used by large populations in some centers for daytime ventilatory support and complements nocturnal NIV via "mask" interfaces for nocturnal ventilatory support. Mouthpiece NIV is also being used for sleep with the mouthpiece fixed in place by a lip-covering flange. Small 15 and 22mm angled mouthpieces and straw-type mouthpieces are the most commonly used. NIV via mouthpiece is being used as an effective alternative to ventilatory support via tracheostomy tube (TMV) and is associated with a reduced risk of pneumonias and other respiratory complications. Its use facilitates "air-stacking" to improve cough, speech, and pulmonary compliance, all of which better maintain quality of life for patients with neuromuscular diseases (NMDs) than the invasive alternatives. Considering these benefits and the new availability of mouthpiece ventilator modes, wider knowledge of this

  3. Thermoregulation and ventilation of termite mounds.

    PubMed

    Korb, Judith

    2003-05-01

    Some of the most sophisticated of all animal-built structures are the mounds of African termites of the subfamily Macrotermitinae, the fungus-growing termites. They have long been studied as fascinating textbook examples of thermoregulation or ventilation of animal buildings. However, little research has been designed to provide critical tests of these paradigms, derived from a very small number of original papers. Here I review results from recent studies on Macrotermes bellicosus that considered the interdependence of ambient temperature, thermoregulation, ventilation and mound architecture, and that question some of the fundamental paradigms of termite mounds. M. bellicosus achieves thermal homeostasis within the mound, but ambient temperature has an influence too. In colonies in comparably cool habitats, mound architecture is adapted to reduce the loss of metabolically produced heat to the environment. While this has no negative consequences in small colonies, it produces a trade-off with gas exchange in large colonies, resulting in suboptimally low nest temperatures and increased CO(2) concentrations. Along with the alteration in mound architecture, the gas exchange/ventilation mechanism also changes. While mounds in the thermally appropriate savannah have a very efficient circular ventilation during the day, the ventilation in the cooler forest is a less efficient upward movement of air, with gas exchange restricted by reduced surface exchange area. These results, together with other recent findings, question entrenched ideas such as the thermosiphon-ventilation mechanism or the assumption that mounds function to dissipate internally produced heat. Models trying to explain the proximate mechanisms of mound building, or building elements, are discussed.

  4. Thermoregulation and ventilation of termite mounds

    NASA Astrophysics Data System (ADS)

    Korb, Judith

    2003-05-01

    Some of the most sophisticated of all animal-built structures are the mounds of African termites of the subfamily Macrotermitinae, the fungus-growing termites. They have long been studied as fascinating textbook examples of thermoregulation or ventilation of animal buildings. However, little research has been designed to provide critical tests of these paradigms, derived from a very small number of original papers. Here I review results from recent studies on Macrotermes bellicosus that considered the interdependence of ambient temperature, thermoregulation, ventilation and mound architecture, and that question some of the fundamental paradigms of termite mounds. M. bellicosus achieves thermal homeostasis within the mound, but ambient temperature has an influence too. In colonies in comparably cool habitats, mound architecture is adapted to reduce the loss of metabolically produced heat to the environment. While this has no negative consequences in small colonies, it produces a trade-off with gas exchange in large colonies, resulting in suboptimally low nest temperatures and increased CO2 concentrations. Along with the alteration in mound architecture, the gas exchange/ventilation mechanism also changes. While mounds in the thermally appropriate savannah have a very efficient circular ventilation during the day, the ventilation in the cooler forest is a less efficient upward movement of air, with gas exchange restricted by reduced surface exchange area. These results, together with other recent findings, question entrenched ideas such as the thermosiphon-ventilation mechanism or the assumption that mounds function to dissipate internally produced heat. Models trying to explain the proximate mechanisms of mound building, or building elements, are discussed.

  5. Regenerative Blower for EVA Suit Ventilation Fan

    NASA Technical Reports Server (NTRS)

    Paul, Heather; Izenson, Mike; Chen, Weibo

    2008-01-01

    Portable life support systems in future space suits will include a ventilation subsystem driven by a dedicated fan. This ventilation fan must meet challenging requirements for pressure rise, flow rate, efficiency, size, safety, and reliability. This paper describes research and development that showed the feasibility of a regenerative blower that is uniquely suited to meet these requirements. We proved feasibility through component tests, blower tests, and design analysis. Based on the requirements for the Constellation Space Suit ventilation fan, we designed the critical elements of the blower. We measured the effects of key design parameters on blower performance using separate effects tests, and used the results of these tests to design a regenerative blower that will meet the ventilation fan requirements. We assembled a proof-of-concept blower and measured its performance at low pressures that simulate a PLSS environment. We obtained head/flow performance curves over a range of operating speeds, identified the maximum efficiency point for the blower, and used these results to specify the design and operating conditions for the ventilation fan. We designed a compact motor that can drive the blower under all anticipated operating requirements and operate with high efficiency during normal operation. We identified materials for the blower that will enhance safety for operation in a lunar environment. We produced a solid model that illustrates the final design. The proof-of-concept blower produced the flow rate and pressure rise needed for the CSSS ventilation subsystem while running at 5400 rpm and consuming only 9 W of electric power and using a non-optimized, commercial motor and controller and inefficient bearings. Scaling the test results to a complete design shows that a lightweight, compact, reliable, and low power blower can meet the performance requirements for future PLSSs.

  6. Early Mobilization of Mechanically Ventilated Patients.

    PubMed

    Hruska, Pam

    2016-12-01

    Critically ill patients requiring mechanical ventilation are least likely to be mobilized and, as a result, are at-risk for prolonged complications from weakness. The use of bed rest and sedation when caring for mechanically ventilated patients is likely shaped by historical practice; however, this review demonstrates early mobilization, with little to no sedation, is possible and safe. Assessing readiness for mobilization in context of progressing patients from passive to active activities can lead to long-term benefits and has been achievable with resource-efficient implementations and team work.

  7. Intermodule ventilation studies for the Space Station

    NASA Technical Reports Server (NTRS)

    Davis, Roy G.; Reuter, James L.

    1987-01-01

    This paper examines the ability of the Space Station intermodule ventilation system to maintain centralized control of CO2 removal and O2 supply. The resulting concentration gradients that will arise are calculated by assuming steady state, ideal gas, isothermal conditions, and perfect mixing of air within and between the pressurized elements. In order to estimate the degree of mixing actually obtained for a given ventilation scheme, a program has been developed based on a potential flow solution technique. Preliminary results from this study indicate that substantial short circuiting and recirculation air flow patterns could arise if a simple duct and diffuser air exchange method at the docking port interface were employed.

  8. Special cases: mechanical ventilation of neurosurgical patients.

    PubMed

    Johnson, Victoria E; Huang, Jason H; Pilcher, Webster H

    2007-04-01

    Mechanical ventilation has evolved greatly over the last half century, guided primarily by improved comprehension of the relevant pathology/physiology. Neurosurgical patients are a unique subgroup of patients who heavily use this technology for both support, and less commonly, as a therapy. Such patients demand special consideration with regard to mode of ventilation, use of positive end-expiratory pressure, and monitoring. In addition, meeting the ventilatory needs of neurosurgical patients while minimizing ventilatory-induced lung damage can be a challenging aspect of care.

  9. Ventilation-perfusion imaging in pulmonary papillomatosis

    SciTech Connect

    Espinola, D.; Rupani, H.; Camargo, E.E.; Wagner, H.N. Jr.

    1981-11-01

    Three children with laryngeal papillomas involving the lungs had serial ventilation-perfusion scintigrams to assess results of therapy designed to reduce the bronchial involvement. Different imaging patterns were observed depending on size, number, and location of lesions. In early parenchymal involvement a ventilation-perfusion mismatch was seen. The initial and follow-up studies correlated well with clinical and radiographic findings. This noninvasive procedure is helpful in evaluating ventilatory and perfusion impairment in these patients as well as their response to treatment.

  10. Preoperational test report, recirculation ventilation systems

    SciTech Connect

    Clifton, F.T.

    1997-11-11

    This represents a preoperational test report for Recirculation Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102 and supports the ability to exhaust air from each tank. Each system consists of a valved piping loop, a fan, condenser, and moisture separator; equipment is located inside each respective tank farm in its own hardened building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  11. 13. NEW YORK SIDE, HUDSON RIVER VENTILATION BUILDING ACROSS HUDSON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. NEW YORK SIDE, HUDSON RIVER VENTILATION BUILDING ACROSS HUDSON RIVER IN BACKGROUND, WITH SOUTH WALL OF NEW JERSEY SIDE OF VENTILATION BUILDING IN FOREGROUND - Holland Tunnel, Beneath Hudson River between New York & Jersey City, New York County, NY

  12. 12. NEW YORK SIDE, HUDSON RIVER VENTILATION BUILDING IN FOREGROUND; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. NEW YORK SIDE, HUDSON RIVER VENTILATION BUILDING IN FOREGROUND; NEW JERSEY SIDE, HUDSON RIVEN VENTILATION BUILDING IN BACKGROUND - Holland Tunnel, Beneath Hudson River between New York & Jersey City, New York County, NY

  13. Indoor Air Quality: Is Increased Ventilation the Answer?

    ERIC Educational Resources Information Center

    Hansen, Shirley

    1989-01-01

    Explains how indoor air quality is affected by pollutants in the air and also by temperature, humidity, and ventilation. Increased ventilation alone seldom solves the "sick building syndrome." Lists ways to improve indoor air quality and optimize energy efficiency. (MLF)

  14. 2. BRICK END ELEVATION WITH X VENTILATORS, REDPAINTED GABLE WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. BRICK END ELEVATION WITH X VENTILATORS, RED-PAINTED GABLE WITH WHITE STARS AND A DOORWAY HOOD. ALSO SHOWS PORTION OF REAR ELEVATION WITH X VENTILATORS - Decorated Red Barn (1852), State Route 100 vicinity, Pottstown, Montgomery County, PA

  15. Ways of improving economy and reliability of mine ventilation

    SciTech Connect

    N.N. Petrov; N.A. Popov

    2004-09-01

    It is established that mine ventilation by main fans operating at maximum capacity results in higher power consumption. The ways are proposed for reduction in the effective power consumption by ventilation and improvement of mining operation safety.

  16. VENTILATION RESEARCH: A REVIEW OF RECENT INDOOR AIR QUALITY LITERATURE

    EPA Science Inventory

    The report gives results of a literature review, conducted to survey and summarize recent and ongoing engineering research into building ventilation, air exchange rate, pollutant distribution and dispersion, and other effects of heating, ventilation, and air-conditioning (HVAC) s...

  17. Elective ventilation for organ donation: law, policy and public ethics.

    PubMed

    Coggon, John

    2013-03-01

    This paper examines questions concerning elective ventilation, contextualised within English law and policy. It presents the general debate with reference both to the Exeter Protocol on elective ventilation, and the considerable developments in legal principle since the time that that protocol was declared to be unlawful. I distinguish different aspects of what might be labelled elective ventilation policies under the following four headings: 'basic elective ventilation'; 'epistemically complex elective ventilation'; 'practically complex elective ventilation'; and 'epistemically and practically complex elective ventilation'. I give a legal analysis of each. In concluding remarks on their potential practical viability, I emphasise the importance not just of ascertaining the legal and ethical acceptability of these and other forms of elective ventilation, but also of assessing their professional and political acceptability. This importance relates both to the successful implementation of the individual practices, and to guarding against possible harmful effects in the wider efforts to increase the rates of posthumous organ donation.

  18. Jet ventilation for surgical interventions in the upper airway.

    PubMed

    Biro, Peter

    2010-09-01

    The clinical applications of jet ventilation (JV) in ear, nose, and throat surgery can be best understood by the characteristics that distinguish this form of ventilation from conventional positive pressure ventilation. By definition, JV is based on the application of gas portions under high pressure through an unblocked catheter into the airway, which is open to the ambient air. Beneficial opportunities arise in JV, which otherwise are not available in regular ventilation.

  19. Measurement of continuous distributions of ventilation-perfusion ratios - Theory

    NASA Technical Reports Server (NTRS)

    Wagner, P. D.; Saltzman, H. A.; West, J. B.

    1974-01-01

    The resolution of the technique considered is sufficient to describe smooth distributions containing blood flow to unventilated regions (shunt), ventilation to unperfused regions (dead space), and up to three additional modes over the range of finite ventilation-perfusion ratios. In particular, areas whose ventilation-perfusion ratios are low can be separated from unventilated regions and those whose ventilation-perfusion ratios are high can similarly be distinguished from unperfused areas.

  20. Preliminary Simulations of the Ullage Dynamics in Microgravity During the Jet Mixing Portion of Tank Pressure Control Experiments

    NASA Technical Reports Server (NTRS)

    Breisacher, Kevin; Moder, Jeffrey

    2015-01-01

    The results of CFD simulations of microgravity tank pressure control experiments performed on the Space Shuttle are presented. A 13.7 liter acrylic model tank was used in these experiments. The tank was filled to an 83 percent fill fraction with Freon refrigerant to simulate cryogenic propellants stored in space. In the experiments, a single liquid jet near the bottom of the tank was used for mixing the tank. Simulations at a range of jet Weber numbers were performed. Qualitative comparisons of the liquid and gas interface dynamics observed and recorded in the experiments and those computed are shown and discussed. The simulations were able to correctly capture jet penetration of the ullage, qualitatively reproduce ullage shapes and dynamics, as well as the final equilibrium position of the ullage.

  1. Preliminary Simulations of the Ullage Dynamics in Microgravity during the Jet Mixing Portion of Tank Pressure Control Experiments

    NASA Technical Reports Server (NTRS)

    Breisacher, Kevin; Moder, Jeffrey

    2015-01-01

    The results of CFD simulations of microgravity tank pressure control experiments performed on the Space Shuttle are presented. A 13.7 liter acrylic model tank was used in these experiments. The tank was filled to an 83 percent fill fraction with Freon refrigerant to simulate cryogenic propellants stored in space. In the experiments, a single liquid jet near the bottom of the tank was used for mixing the tank. Simulations at a range of jet Weber numbers were performed. Qualitative comparisons of the liquid and gas interface dynamics observed and recorded in the experiments and those computed are shown and discussed. The simulations were able to correctly capture jet penetration of the ullage, qualitatively reproduce ullage shapes and dynamics, as well as the final equilibrium position of the ullage.

  2. Systolic Blood Pressure Control Among Individuals With Type 2 Diabetes: A Comparative Effectiveness Analysis of Three Interventions

    PubMed Central

    Probstfield, Jeffery; Hire, Donald; Redmon, J. Bruce; Evans, Gregory W.; Coday, Mace; Lewis, Cora E.; Johnson, Karen C.; Wilmoth, Sharon; Bahnson, Judy; Dulin, Michael F.; Green, Jennifer B.; Knowler, William C.; Kitabchi, Abbas; Murillo, Anne L.; Osei, Kwame; Rehman, Shakaib U.; Cushman, William C.

    2015-01-01

    BACKGROUND The relative effectiveness of 3 approaches to blood pressure control—(i) an intensive lifestyle intervention (ILI) focused on weight loss, (ii) frequent goal-based monitoring of blood pressure with pharmacological management, and (iii) education and support—has not been established among overweight and obese adults with type 2 diabetes who are appropriate for each intervention. METHODS Participants from the Action for Health in Diabetes (Look AHEAD) and the Action to Control Cardiovascular Risk in Diabetes (ACCORD) cohorts who met criteria for both clinical trials were identified. The proportions of these individuals with systolic blood pressure (SBP) <140mm Hg from annual standardized assessments over time were compared with generalized estimating equations. RESULTS Across 4 years among 480 Look AHEAD and 1,129 ACCORD participants with baseline SBPs between 130 and 159mm Hg, ILI (OR = 1.46; 95% CI = [1.18–1.81]) and frequent goal-based monitoring with pharmacotherapy (OR = 1.51; 95% CI = [1.16–1.97]) yielded higher rates of blood pressure control compared to education and support. The intensive behavioral-based intervention may have been more effective among individuals with body mass index >30kg/m2, while frequent goal-based monitoring with medication management may be more effective among individuals with lower body mass index (interaction P = 0.047). CONCLUSIONS Among overweight and obese adults with type 2 diabetes, both ILI and frequent goal-based monitoring with pharmacological management can be successful strategies for blood pressure control. CLINICAL TRIALS REGISTRY clinicaltrials.gov identifiers NCT00017953 (Look AHEAD) and NCT00000620 (ACCORD). PMID:25666468

  3. 46 CFR 127.260 - Ventilation for accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... vessel of 100 or more gross tons must be provided with a mechanical ventilation system unless the... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation for accommodations. 127.260 Section 127.260... ARRANGEMENTS Particular Construction and Arrangements § 127.260 Ventilation for accommodations. (a)...

  4. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Ventilation for closed spaces. 92.15-10 Section 92.15-10... CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except as noted in paragraph (c) of this section, all enclosed spaces within the vessel shall be properly vented or...

  5. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Machinery space, ventilation. 58.01-45 Section 58.01-45... MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each machinery space must be ventilated to ensure that, when machinery or boilers are operating at full power in...

  6. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Ventilation for enclosed spaces. 127.250 Section 127.250... ARRANGEMENTS Particular Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each enclosed space within the vessel must be properly vented or ventilated. Means must be provided for...

  7. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Ventilation for enclosed spaces. 127.250 Section 127.250... ARRANGEMENTS Particular Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each enclosed space within the vessel must be properly vented or ventilated. Means must be provided for...

  8. 46 CFR 190.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Ventilation for closed spaces. 190.15-10 Section 190.15... CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-10 Ventilation for closed spaces. (a) All enclosed spaces... chemical laboratories, scientific laboratories, chemical storerooms, and machinery spaces and for...

  9. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Machinery space, ventilation. 58.01-45 Section 58.01-45... MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each machinery space must be ventilated to ensure that, when machinery or boilers are operating at full power in...

  10. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Ventilation for closed spaces. 92.15-10 Section 92.15-10... CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except as noted in paragraph (c) of this section, all enclosed spaces within the vessel shall be properly vented or...

  11. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Ventilation (other than machinery spaces). 169.315... spaces). (a) All enclosed spaces within the vessel must be properly ventilated in a manner suitable for the purpose of the space. (b) A means must be provided to close off all vents and ventilators....

  12. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Ventilation for enclosed spaces. 127.250 Section 127.250... ARRANGEMENTS Particular Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each enclosed space within the vessel must be properly vented or ventilated. Means must be provided for...

  13. 46 CFR 190.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Ventilation for closed spaces. 190.15-10 Section 190.15... CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-10 Ventilation for closed spaces. (a) All enclosed spaces... chemical laboratories, scientific laboratories, chemical storerooms, and machinery spaces and for...

  14. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Machinery space, ventilation. 58.01-45 Section 58.01-45... MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each machinery space must be ventilated to ensure that, when machinery or boilers are operating at full power in...

  15. 46 CFR 190.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Ventilation for closed spaces. 190.15-10 Section 190.15... CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-10 Ventilation for closed spaces. (a) All enclosed spaces... chemical laboratories, scientific laboratories, chemical storerooms, and machinery spaces and for...

  16. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Ventilation for closed spaces. 92.15-10 Section 92.15-10... CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except as noted in paragraph (c) of this section, all enclosed spaces within the vessel shall be properly vented or...

  17. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Ventilation and drainage. 27.1187 Section... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Powerplant Fire Protection § 27.1187 Ventilation... for ventilation and drainage of flammable fluids. The drainage means must be— (a) Effective...

  18. 46 CFR 78.47-75 - Ventilation alarm failure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 3 2011-10-01 2011-10-01 false Ventilation alarm failure. 78.47-75 Section 78.47-75... Fire and Emergency Equipment, Etc. § 78.47-75 Ventilation alarm failure. (a) The alarm required by § 72.15-15 (c)(4) of this subchapter, which indicates the loss of required ventilation in spaces...

  19. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ventilation and drainage. 27.1187 Section... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Powerplant Fire Protection § 27.1187 Ventilation... for ventilation and drainage of flammable fluids. The drainage means must be— (a) Effective...

  20. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Ventilation (other than machinery spaces). 169.315... SCHOOL VESSELS Construction and Arrangement Hull Structure § 169.315 Ventilation (other than machinery... provide adequate ventilation in all ordinary weather conditions. Provided that paragraph (a) of...