Sample records for pressure-controlled ventilation pcv

  1. Volume-controlled versus pressure-controlled ventilation-volume guaranteed mode during one-lung ventilation

    PubMed Central

    Song, Seok Young; Cho, Min-Su; Kim, Jong Hae; Ryu, Tae Ha; Kim, Bong IL

    2014-01-01

    Background The purpose of this study was to investigate the changes in airway pressure and arterial oxygenation between ventilation modes during one-lung ventilation (OLV) in patients undergoing thoracic surgery. Methods We enrolled 27 patients for thoracic surgery with OLV in the lateral decubitus position. The subjects received various modes of ventilation in random sequences during surgery, including volume-controlled ventilation (VCV) and pressure-controlled ventilation-volume guaranteed (PCV-VG) with a tidal volume (TV) of 8 ml/kg of actual body weight. Target-controlled infusion (TCI) with propofol and remifentanil was used for anesthesia induction and maintenance. After double-lumen endobronchial tube (DLT) insertion, the proper positioning of the DLT was assessed using a fiberoptic bronchoscope. Peak inspiratory pressure (Ppeak), exhaled TV, and arterial blood gas were measured 30 min after each ventilation mode. Results Ppeak was significantly reduced with the PCV-VG mode (19.6 ± 2.5 cmH2O) compared with the VCV mode (23.2 ± 3.1 cmH2O) (P < 0.000). However, no difference in arterial oxygen tension was noted between the groups (PCV-VG, 375.8 ± 145.1 mmHg; VCV, 328.1 ± 123.7 mmHg) (P = 0.063). The exhaled TV was also significantly increased in PCV-VG compared with VCV (451.4 ± 85.4 vs. 443.9 ± 85.9 ml; P = 0.035). Conclusions During OLV in patients with normal lung function, although PCV-VG did not provide significantly improved arterial oxygen tension compared with VCV, PCV-VG provided significantly attenuated airway pressure despite significantly increased exhaled TV compared with VCV. PMID:25368784

  2. Ventilation during laparoscopic-assisted bariatric surgery: volume-controlled, pressure-controlled or volume-guaranteed pressure-regulated modes

    PubMed Central

    Dion, Joanna M; McKee, Chris; Tobias, Joseph D; Sohner, Paul; Herz, Daniel; Teich, Steven; Rice, Julie; Barry, N’ diris; Michalsky, Marc

    2014-01-01

    Introduction: Managing ventilation and oxygenation during laparoscopic procedures in severely obese patients undergoing weight loss surgery presents many challenges. Pressure-controlled ventilation, volume-guaranteed (PCV-VG) is a dual-control mode of ventilation and an alternative to pressure (PC) or volume (VC) controlled ventilation. PCV-VG features a user-selected tidal volume target, that is auto-regulated and pressure controlled. We hypothesized that PCV-VG ventilation would provide improved oxygenation and ventilation during laparoscopic bariatric surgery with a lower peak inflating pressure (PIP) than either PC or VC ventilation. Methods: This was a prospective cross-over cohort trial (n = 20). In random sequence each patient received the three modes of ventilation for 20 minutes during the laparoscopic portion of the procedure. For all modes of ventilation the goal tidal volume was 6-8 mL/kg, and the respiratory rate was adjusted to achieve normocarbia. The PIP, exhaled tidal volume, respiratory rate, and oxygen saturation were recorded every five minutes. At the end of 20 minutes, an arterial blood gas was obtained. Data were analyzed using a paired t-test. Results: PCV-VG and PC ventilation both resulted in significantly lower PIP (cmH2O) than VC ventilation (30.5 ± 3.0, 31.6 ± 4.9, and 36.3 ± 3.4 mmHg respectively; p < 0.01 for PCV-VG vs. VC and PC vs. VC). There was no difference in oxygenation (PaO2), ventilation (PaCO2) or hemodynamic variables between the three ventilation modes. Conclusions: In adolescents and young adults undergoing laparoscopic bariatric surgery, PCV-VG and PC were superior to VC ventilation in their ability to provide ventilation with the lowest PIP. PMID:25232415

  3. Change in expiratory flow detects partial endotracheal tube obstruction in pressure-controlled ventilation.

    PubMed

    Kawati, Rafael; Vimlati, Laszlo; Guttmann, Josef; Hedenstierna, Göran; Sjöstrand, Ulf; Schumann, Stefan; Lichtwarck-Aschoff, Michael

    2006-09-01

    Only extreme degrees of endotracheal tube (ETT) narrowing can be detected with monitoring of tidal volume (V(T)) during pressure-controlled ventilation (PCV). To assess the degree of ETT obstruction in PCV and to compare it to V(T) monitoring, we produced 3 levels of partial ETT obstruction in 11 healthy anesthetized piglets using ETTs of 4 different inner diameters (IDs 9.0, 8.0, 7.0, and 6.0 mm). An expiratory flow over volume ((e)-V) curve was plotted and the time constant (tau(e)) at 15% of expiration time (T(e)) was calculated. We also calculated the fractional volume expired during the first 15% of T(e) (V(ex fract,15)) and compared those variables to full expiratory V(T) for each of the 3 obstructions. V(T) monitoring failed to detect ETT narrowing. By contrast, V(ex fract,15) decreased and tau(e) increased significantly with increasing ETT narrowing (for IDs 9.0, 8.0, 7.0, and 6.0, mean V(ex fract,15) was 195, 180, 146, and 134 mL respectively and mean tau(e) was 380, 491, 635, 794 ms for IDs 9.0, 8.0, 7.0, and 6.0 respectively). We conclude that when the elastic recoil that drives (e) is appropriately considered, analysis of (e) and V(ex fract,15) detects partial ETT obstruction during PCV. PMID:16931676

  4. Hepatic effects of lung-protective pressure-controlled ventilation and a combination of high-frequency oscillatory ventilation and extracorporeal lung assist in experimental lung injury

    PubMed Central

    Kredel, Markus; Muellenbach, Ralf M.; Johannes, Amélie; Brederlau, Joerg; Roewer, Norbert; Wunder, Christian

    2011-01-01

    Summary Background Ventilation with high positive end-expiratory pressure (PEEP) can lead to hepatic dysfunction. The aim of this study was to investigate the hepatic effects of strategies using high airway pressures either in pressure-controlled ventilation (PCV) or in high-frequency oscillatory ventilation (HFOV) combined with an arteriovenous extracorporeal lung assist (ECLA). Material/Methods Pietrain pigs underwent induction of lung injury by saline lavage. Ventilation was continued for 24 hours either as PCV with tidal volumes of 6 ml/kg and PEEP 3 cmH2O above the lower inflection point of the pressure-volume curve or as HFOV (?12 Hz) with a mean tracheal airway pressure 3 cmH2O above the lower inflection point combined with arteriovenous ECLA (HFOV+ECLA). Fluids and norepinephrine stabilized the circulation. The indocyanine green plasma disappearance rate, serum bilirubin, aspartate aminotransferase, alanine aminotransferase, ?-glutamyltransferase, alkaline phosphatase, glutamate dehydrogenase, lactate dehydrogenase and creatine kinase were determined repeatedly. Finally, liver neutrophils were counted and liver cell apoptosis was assessed by terminal deoxynucleotidyl transferase nick end labeling (TUNEL). Results Aspartate aminotransferase increased in the PCV group about three-fold and in the HFOV+ECLA group five-fold (p<0.001). Correspondingly, creatine kinase increased about two-fold and four-fold, respectively (p<0.001). Lactate dehydrogenase was increased in the HFOV+ECLA group (p<0.028). The number of neutrophils infiltrating the liver tissue and the apoptotic index were low. Conclusions High airway pressure PCV and HFOV with ECLA in the treatment of lavage-induced lung injury in pigs did not cause liver dysfunction or damage. The detected elevation of enzymes might be of extrahepatic origin. PMID:21959601

  5. Continuous endotracheal tube cuff pressure control system protects against ventilator-associated pneumonia

    PubMed Central

    2014-01-01

    Introduction The use of a system for continuous control of endotracheal tube cuff pressure reduced the incidence of ventilator-associated pneumonia (VAP) in one randomized controlled trial (RCT) with 112 patients but not in another RCT with 142 patients. In several guidelines on the prevention of VAP, the use of a system for continuous or intermittent control of endotracheal cuff pressure is not reviewed. The objective of this study was to compare the incidence of VAP in a large sample of patients (n?=?284) treated with either continuous or intermittent control of endotracheal tube cuff pressure. Methods We performed a prospective observational study of patients undergoing mechanical ventilation during more than 48 hours in an intensive care unit (ICU) using either continuous or intermittent endotracheal tube cuff pressure control. Multivariate logistic regression analysis (MLRA) and Cox proportional hazard regression analysis were used to predict VAP. The magnitude of the effect was expressed as odds ratio (OR) or hazard ratio (HR), respectively, and 95% confidence interval (CI). Results We found a lower incidence of VAP with the continuous (n?=?150) than with the intermittent (n?=?134) pressure control system (22.0% versus 11.2%; p?=?0.02). MLRA showed that the continuous pressure control system (OR?=?0.45; 95% CI?=?0.22-0.89; p?=?0.02) and the use of an endotracheal tube incorporating a lumen for subglottic secretion drainage (SSD) (OR?=?0.39; 95% CI?=?0.19-0.84; p?=?0.02) were protective factors against VAP. Cox regression analysis showed that the continuous pressure control system (HR?=?0.45; 95% CI?=?0.24-0.84; p?=?0.01) and the use of an endotracheal tube incorporating a lumen for SSD (HR?=?0.29; 95% CI?=?0.15-0.56; p?pressure control system (continuous or intermittent) and endotracheal tube (with or without SSD) was not statistically significant in MLRA (OR?=?0.41; 95% CI?=?0.07-2.37; p?=?0.32) or in Cox analysis (HR?=?0.35; 95% CI?=?0.06-1.84; p?=?0.21). Conclusions The use of a continuous endotracheal cuff pressure control system and/or an endotracheal tube with a lumen for SSD could help to prevent VAP in patients requiring more than 48 hours of mechanical ventilation. PMID:24751286

  6. Effect of intra-operative pressure support vs pressure controlled ventilation on oxygenation and lung function in moderately obese adults.

    PubMed

    Zoremba, M; Kalmus, G; Dette, F; Kuhn, C; Wulf, H

    2010-02-01

    Obesity impairs peri-operative lung function. To evaluate the impact of pressure support ventilation vs pressure controlled ventilation in moderately obese adults upon early postoperative lung function, we randomly assigned 68 moderately obese patients (body mass index 25-35 kg x m(-2)) undergoing minor surgery to receive intra-operative ventilation either with pressure support or pressure controlled ventilation. We performed intra-operative blood gas analysis and measured pulse oximetry saturation, spirometry values at pre-operative assessment (baseline) and at 10 min, 30 min, 2 h and 24 h after extubation. The intra-operative oxygenation index (arterial partial pressure of oxygen/fraction of inspired oxygen) in the pressure support ventilation group was significantly improved over time (p < 0.0001). Postoperatively, the pressure support ventilation group also had better lung function and oxygenation values than did the pressure controlled ventilation group (p < 0.005). We conclude that pressure support ventilation better maintains lung function than pressure controlled ventilation in moderately overweight patients scheduled for minor surgery. PMID:19958342

  7. Pressure Dynamic Characteristics of Pressure Controlled Ventilation System of a Lung Simulator

    PubMed Central

    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. PMID:25197318

  8. Randomized clinical trial of pressure-controlled inverse ratio ventilation and extracorporeal CO2 removal for adult respiratory distress syndrome.

    PubMed

    Morris, A H; Wallace, C J; Menlove, R L; Clemmer, T P; Orme, J F; Weaver, L K; Dean, N C; Thomas, F; East, T D; Pace, N L; Suchyta, M R; Beck, E; Bombino, M; Sittig, D F; Böhm, S; Hoffmann, B; Becks, H; Butler, S; Pearl, J; Rasmusson, B

    1994-02-01

    The impact of a new therapy that includes pressure-controlled inverse ratio ventilation followed by extracorporeal CO2 removal on the survival of patients with severe ARDS was evaluated in a randomized controlled clinical trial. Computerized protocols generated around-the-clock instructions for management of arterial oxygenation to assure equivalent intensity of care for patients randomized to the new therapy limb and those randomized to the control, mechanical ventilation limb. We randomized 40 patients with severe ARDS who met the ECMO entry criteria. The main outcome measure was survival at 30 days after randomization. Survival was not significantly different in the 19 mechanical ventilation (42%) and 21 new therapy (extracorporeal) (33%) patients (p = 0.8). All deaths occurred within 30 days of randomization. Overall patient survival was 38% (15 of 40) and was about four times that expected from historical data (p = 0.0002). Extracorporeal treatment group survival was not significantly different from other published survival rates after extracorporeal CO2 removal. Mechanical ventilation patient group survival was significantly higher than the 12% derived from published data (p = 0.0001). Protocols controlled care 86% of the time. Average PaO2 was 59 mm Hg in both treatment groups. Intensity of care required to maintain arterial oxygenation was similar in both groups (2.6 and 2.6 PEEP changes/day; 4.3 and 5.0 FIO2 changes/day). We conclude that there was no significant difference in survival between the mechanical ventilation and the extracorporeal CO2 removal groups. We do not recommend extracorporeal support as a therapy for ARDS. Extracorporeal support for ARDS should be restricted to controlled clinical trials. PMID:8306022

  9. Pneumococcal Vaccines (PCV, PPSV)

    MedlinePLUS

    ... Pregnancy Precautions Checkups: What to Expect Your Child's Immunizations: Pneumococcal Vaccines (PCV, PPSV) KidsHealth > Parents > General Health > ... but also help stop the infections from spreading. Immunization Schedule PCV13 immunizations are given to all infants ...

  10. PCV valve flutter : vibration characterization through pressure and flow

    E-print Network

    Gomez, Nicasio

    2005-01-01

    A Positive Crankcase Ventilation, or PCV, valve is required by internal combustion engines in order to regulate the flow of blow-by gases out of the crankcase and into the intake air stream. Fluctuations in the pressure ...

  11. Effect of porcine circovirus type 2 (PCV2) vaccination on PCV2-viremic piglets after experimental PCV2 challenge

    PubMed Central

    2014-01-01

    The objective of this study was to evaluate the effect of porcine circovirus type 2 (PCV2) vaccines on PCV2-viremic and -seropositive piglets born from naturally PCV2-infected sows against postnatal PCV2 challenge. The experimental design was aimed at mimicking commercial swine rearing conditions to evaluate the response of the PCV2 vaccine on PCV2-viremic and -seropositive piglets after experimental PCV2 challenge. PCV2a (or 2b)-viremic piglets received a PCV2 vaccine at 21 days of age followed by a PCV2b (or 2a) challenge at 49 days of age (28 days post vaccination). The PCV2 vaccines elicited a high level of humoral (as measured by immunoperoxidase monolayer assay and neutralizing antibody titers) and cellular (as measured by the frequency of PCV2-specific interferon-?-secreting cells) immune response in the PCV2-viremic piglets after vaccination even in the presence of maternally derived antibodies (MDA). The initial infection of PCV2 in the pigs was not affected by PCV2 vaccination, however the challenging PCV2 was reduced by PCV2 vaccination on PCV2-viremic pigs. The results from this study demonstrate that the PCV2 vaccine used in this study is effective at reducing PCV2 viremia and lymphoid PCV2 DNA, even for PCV2-viremic pigs with passively acquired MDA at the time of vaccination. PMID:24484292

  12. 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

  13. Impact of Ventilatory Modes on the Breathing Variability in Mechanically Ventilated Infants

    PubMed Central

    Baudin, Florent; Wu, Hau-Tieng; Bordessoule, Alice; Beck, Jennifer; Jouvet, Philippe; Frasch, Martin G.; Emeriaud, Guillaume

    2014-01-01

    Objectives: Reduction of breathing variability is associated with adverse outcome. During mechanical ventilation, the variability of ventilatory pressure is dependent on the ventilatory mode. During neurally adjusted ventilatory assist (NAVA), the support is proportional to electrical activity of the diaphragm (EAdi), which reflects the respiratory center output. The variability of EAdi is, therefore, translated into a similar variability in pressures. Contrastingly, conventional ventilatory modes deliver less variable pressures. The impact of the mode on the patient’s own respiratory drive is less clear. This study aims to compare the impact of NAVA, pressure-controlled ventilation (PCV), and pressure support ventilation (PSV) on the respiratory drive patterns in infants. We hypothesized that on NAVA, EAdi variability resembles most of the endogenous respiratory drive pattern seen in a control group. Methods: Electrical activity of the diaphragm was continuously recorded in 10 infants ventilated successively on NAVA (5?h), PCV (30?min), and PSV (30?min). During the last 10?min of each period, the EAdi variability pattern was assessed using non-rhythmic to rhythmic (NRR) index. These variability profiles were compared to the pattern of a control group of 11 spontaneously breathing and non-intubated infants. Results: In control infants, NRR was higher as compared to mechanically ventilated infants (p?PCV. PSV exhibited an intermediary pattern. Perspectives: Mechanical ventilation impacts the breathing variability in infants. NAVA produces EAdi pattern resembling most that of control infants. NRR can be used to characterize respiratory variability in infants. Larger prospective studies are necessary to understand the differential impact of the ventilatory modes on the cardio-respiratory variability and to study their impact on clinical outcomes. PMID:25505779

  14. High frequency oscillatory ventilation and prone positioning in a porcine model of lavage-induced acute lung injury

    PubMed Central

    Brederlau, Joerg; Muellenbach, Ralf; Kredel, Markus; Greim, Clemens; Roewer, Norbert

    2006-01-01

    Background This animal study was conducted to assess the combined effects of high frequency oscillatory ventilation (HFOV) and prone positioning on pulmonary gas exchange and hemodynamics. Methods Saline lung lavage was performed in 14 healthy pigs (54 ± 3.1 kg, mean ± SD) until the arterial oxygen partial pressure (PaO2) decreased to 55 ± 7 mmHg. The animals were ventilated in the pressure controlled mode (PCV) with a positive endexpiratory pressure (PEEP) of 5 cmH2O and a tidal volume (VT) of 6 ml/kg body weight. After a stabilisation period of 60 minutes, the animals were randomly assigned to 2 groups. Group 1: HFOV in supine position; group 2: HFOV in prone position. After evaluation of prone positioning in group 2, the mean airway pressure (Pmean) was increased by 3 cmH2O from 16 to 34 cmH2O every 20 minutes in both groups accompanied by measurements of respiratory and hemodynamic variables. Finally all animals were ventilated supine with PCV, PEEP = 5 cm H2O, VT = 6 ml/kg. Results Combination of HFOV with prone positioning improves oxygenation and results in normalisation of cardiac output and considerable reduction of pulmonary shunt fraction at a significant (p < 0.05) lower Pmean than HFOV and supine positioning. Conclusion If ventilator induced lung injury is ameliorated by a lower Pmean, a combined treatment approach using HFOV and prone positioning might result in further lung protection. PMID:16584548

  15. 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.

  16. Differential effects of porcine circovirus type 2 (PCV2) vaccination on PCV2 genotypes at Japanese pig farms.

    PubMed

    Takahagi, Yoichi; Toki, Shinji; Nishiyama, Yasutaka; Morimatsu, Fumiki; Murakami, Hiroshi

    2010-01-01

    Infection of pigs with porcine circovirus type 2 (PCV2) causes a variety of disorders collectively referred to as porcine circovirus associated diseases (PCVADs). PCV2 isolates can be classified into two major types: PCV2a and PCV2b. In the present study, effects of vaccination on antibody titers in sera, PCV2 viremia, and shedding of PCV2 in feces were studied on Japanese commercial pig farms where vaccination of piglets against PCV2 was performed using commercially available vaccines. The effectiveness of vaccination against various PCV2 genotypes was also assessed. Among the 16 farms studied, 10 and 6 had been infected with PCV2a and PCV2b, respectively. PCV2a was further subdivided into PCV2a-1 and PCV2a-2. PCV2a-1 and PCV2a-2 prevailed on 6 and 4 farms, respectively, among the 10 farms infected with PCV2a. The PCV2 vaccines were effective in reducing PCV2 infection on commercial pig farms. Mean mortality rates were significantly decreased over 8 months after the start of the PCV2 vaccination program as compared to those before the start of the PCV2 vaccination program on farms infected with PCV2a-2 (20.8% vs. 12.1%) and PCV2b (26.5% vs. 13.7%). On the farms with PCV2a-1 infected pigs, there was no significant difference in the mean mortality rate before versus after the start of the vaccination program (14.7% vs. 14.1%). Mortality rate reduction with the PCV2 vaccination might depend on the genetic types of PCV2. PMID:19915335

  17. 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...

  18. Original article Porcine circovirus type 2 (PCV2)-infection

    E-print Network

    Paris-Sud XI, Université de

    Original article Porcine circovirus type 2 (PCV2)-infection and re-inoculation with homologous infection with genotypes PCV2a and PCV2b may play a role in the development of clinical porcine circovirus / serological response 1. INTRODUCTION Porcine circovirus type 2 (PCV2) is a small, single-stranded, circular

  19. 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...

  20. Singular PCV2a or PCV2b Infection Results in Apoptosis of Hepatocytes in Clinically Affected Gnotobiotic Pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Systemic infection with porcine circovirus type 2 (PCV2) is often clinically associated with respiratory signs, failure to thrive and diarrhea [1]. Currently, PCV2 can be further subdivided into two main genotypes, PCV2a and PCV2b which under experimental conditions result in very simi...

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

    PubMed

    Sinha, Avanti; Schalk, Shayleen; Lager, Kelly M; Wang, Chong; Opriessnig, Tanja

    2012-02-01

    Porcine circovirus type 2 (PCV2) is clinically associated with respiratory disease, failure-to-thrive, hepatitis, and diarrhea; however, the precise pathogenesis of PCV2-associated disease and in particular its involvement in apoptosis is still controversial. The objectives of this study were (1) to determine whether PCV2 is associated with apoptosis by examining and comparing hepatic tissues from clinically affected or unaffected gnotobiotic pigs that were experimentally infected with PCV2, (2) to determine if there are differences between PCV2a and PCV2b in inducing hepatocyte apoptosis, and (3) to determine if there are differences between apoptosis detection systems. Forty-eight gnotobiotic pigs were separated into five groups based on inoculation status and development of clinical disease: (1) sham-inoculated, clinically-unaffected (n=4), (2) inoculated with PCV2a, clinically-unaffected (n=10), (3) inoculated with PCV2a, clinically-affected (n=6), (4) inoculated with PCV2b, clinically-unaffected, (n=13) and (5) inoculated with PCV2b, clinically-affected (n=15). Formalin-fixed, paraffin-embedded sections of liver from all pigs were analyzed for signs of apoptosis [presence of single strand DNA breaks in the nucleus by the terminal transferase dUTP nick end labeling (TUNEL) assay or presence of intra-nuclear cleaved caspase 3 (CCasp3) demonstrated by CCasp3 immunohistochemistry (IHC)]. In addition, the liver tissues were also tested for presence of cytoplasmic and intra-nuclear PCV2 antigen by an IHC assay. Specific CCasp3 and TUNEL labeling was detected in the nucleus of hepatocytes in PCV2a and PCV2b infected pigs with significantly (P<0.05) higher levels of apoptotic cells in clinically-affected pigs. Regardless of PCV2 subtype (PCV2a; PCV2b), there were higher levels of PCV2 antigen in clinically-affected pigs compared to clinically-unaffected pigs. There was no significant difference in detection rate of apoptotic cells between the TUNEL assay and CCasp3 IHC. When high amounts of PCV2 antigen were present, the incidence of CCasp3 and TUNEL staining also increased regardless of the PCV2 genotype. This suggests that PCV2-induced apoptosis of hepatocytes is important in the pathogenesis of PCV2-associated lesions and disease. PMID:21074229

  2. Blood Pressure Control in Diabetes

    PubMed Central

    Cummings, Doyle M.; Doherty, Lisa; Howard, George; Howard, Virginia J.; Safford, Monika M.; Prince, Valerie; Kissela, Brett; Lackland, Daniel T.

    2010-01-01

    OBJECTIVE Despite widespread dissemination of target values, achieving a blood pressure of <130/80 mmHg is challenging for many individuals with diabetes. The purpose of the present study was to examine temporal trends in blood pressure control in hypertensive individuals with diabetes as well as the potential for race, sex, and geographic disparities. RESEARCH DESIGN AND METHODS We analyzed baseline data from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study, a national, population-based, longitudinal cohort study of 30,228 adults (58% European American and 42% African American), examining the causes of excess stroke mortality in the southeastern U.S. We calculated mean blood pressure and blood pressure control rates (proportion with blood pressure <130/80 mmHg) for 5,217 hypertensive diabetic participants by year of enrollment (2003–2007) using multivariable logistic regression models. RESULTS Only 43 and 30% of European American and African American diabetic hypertensive participants, respectively, demonstrated a target blood pressure of <130/80 mmHg (P < 0.001). However, a temporal trend of improved control was evident; the odds of having a blood pressure <130/80 mmHg among diabetic hypertensive participants of both races enrolled in 2007 (as compared with those enrolled in 2003) were ?50% greater (P < 0.001) in multivariate models. CONCLUSIONS These data suggest temporal improvements in blood pressure control in diabetes that may reflect broad dissemination of tighter blood pressure control targets and improving medication access. However, control rates remain low, and significant racial disparities persist among African Americans that may contribute to an increased risk for premature cardiovascular disease. PMID:20097785

  3. 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. PMID:6754938

  4. Susceptibility of calves to porcine circovirus-2 (PCV2).

    PubMed

    Halami, Mohammad Y; Freick, Markus; Shehata, Awad A; Müller, Hermann; Vahlenkamp, Thomas W

    2014-09-17

    Circoviruses are known to infect pigs and birds and cause severe diseases with various clinical signs. Porcine circovirus-2 (PCV2), associated with severe economic losses, was detected in rodents, mosquitoes, cattle, and in calves affected with bovine neonatal pancytopenia (BNP). However, molecular and serological investigations on circovirus infections in cattle revealed inconsistent results. The aim of the study was to investigate the susceptibility and immune response of calves to experimental PCV2 inoculation. Animals were either intravenously inoculated with tissue-culture grown PCV2, with bone marrow from PCV2 positive and negative calves or immunized with a commercial inactivated PCV2 vaccine. The results showed that the animals inoculated with tissue-culture grown PCV2 and with PCV2 positive bone marrow displayed clinical signs including lymph node swelling, reddening of oral and ocular mucosa, and diarrhoea 7-18 days post inoculation (p.i.). PCV2-specific antibodies were detected in the tissue-culture grown PCV2-infected animals and in the PCV2-immunized animals from day 11 and 7 p.i. onwards, respectively, but were absent in both bone marrow inoculated groups. PCV2 was detected by real-time quantitative PCR only in blood samples of the tissue-culture grown PCV2-infected animals and in various tissues (e.g. spleen, lymph nodes, thymus), with high copy numbers in blood between day 4 (5.16log10 genomic copy number/ml) and 46 (5.33log10 genomic copy number/ml) p.i. In conclusion, the seroconversion and the detection of PCV2 in lymphoid tissues for more than five weeks p.i. revealed that host susceptibility of PCV2 is not solely restricted to pigs. PMID:25085519

  5. Transcription Analysis of Porcine Circovirus (PCV)

    Microsoft Academic Search

    Joachim Mankertz; Hans-Joerg Buhk; Gunnar Blaess; Annette Mankertz

    1998-01-01

    This study focuses on gene expression of porcine circovirus (PCV) in order to identify viral genes and their corresponding\\u000a mRNA transcripts. By northern blot analysis, the existence of three mRNAs could be demonstrated. Two mRNAs are encoded by\\u000a the viral (?)-strand and one is encoded by the viral (+)-strand. The (+)-strand encoded mRNA transcript is 990 nucleotides\\u000a (nt) long and

  6. Mechanical Ventilation in Children - Problems and Issues.

    PubMed

    Zieli?ska, Marzena; Zieli?ski, Stanis?aw; Sniatkowska-Bartkowska, Alicja

    2014-01-01

    Respiratory failure is the leading reason for the admission of children to intensive care units, and the ventilator is the main therapeutic tool used during the treatment of these patients. A competently used ventilator and adequate knowledge of the anatomy, histology and physiology of the respiratory system in particular age groups of children (especially among neonates and infants) are crucial for successful treatment. Both non-invasive and invasive ventilation modes can be used for respiratory treatment in children. Invasive ventilation modes can be divided into two groups: conventional ones such as pressure-controlled or volume-controlled ventilation, or non-conventional modes such as oscillatory ventilation. Mechanical ventilation can involve a high risk of serious complications, such as pressure injury (barotrauma), volume injury (volutrauma) and biotrauma. Adhering to the principles of lung-protective ventilation can reduce the risk of side effects of mechanical ventilation. PMID:25491702

  7. Immunogenicity and Pathogenicity of Chimeric Infectious DNA Clones of Pathogenic Porcine Circovirus Type 2 (PCV2) and Nonpathogenic PCV1 in Weanling Pigs

    PubMed Central

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

    2003-01-01

    Porcine circovirus type 2 (PCV2) is the primary causative agent of postweaning multisystemic wasting syndrome (PMWS), whereas the ubiquitous porcine circovirus type 1 (PCV1) is nonpathogenic for pigs. We report here the construction and characterization of two chimeric infectious DNA clones of PCV1 and PCV2. The chimeric PCV1-2 clone contains the PCV2 capsid gene cloned in the backbone of the nonpathogenic PCV1 genome. A reciprocal chimeric PCV2-1 DNA clone was also constructed by replacing the PCV2 capsid gene with that of PCV1 in the backbone of the PCV2 genome. The PCV1, PCV2, and chimeric PCV1-2 and PCV2-1 DNA clones were all shown to be infectious in PK-15 cells, and their growth characteristics in vitro were determined and compared. To evaluate the immunogenicity and pathogenicity of the chimeric infectious DNA clones, 40 specific-pathogen-free (SPF) pigs were randomly assigned into five groups of eight pigs each. Group 1 pigs received phosphate-buffered saline as the negative control. Group 2 pigs were each injected in the superficial inguinal lymph nodes with 200 ?g of the PCV1 infectious DNA clone. Group 3 pigs were each similarly injected with 200 ?g of the PCV2 infectious DNA clone, group 4 pigs were each injected with 200 ?g of the chimeric PCV1-2 infectious DNA clone, and group 5 pigs were each injected with 200 ?g of the reciprocal chimeric PCV2-1 infectious DNA clone. As expected, seroconversion to antibodies to the PCV2 capsid antigen was detected in group 3 and group 4 pigs. Group 2 and 5 pigs all seroconverted to PCV1 antibody. Gross and microscopic lesions in various tissues of animals inoculated with the PCV2 infectious DNA clone were significantly more severe than those found in pigs inoculated with PCV1, chimeric PCV1-2, and reciprocal chimeric PCV2-1 infectious DNA clones. These data indicated that the chimeric PCV1-2 virus with the immunogenic ORF2 capsid gene of pathogenic PCV2 cloned into the nonpathogenic PCV1 genomic backbone induces a specific antibody response to the pathogenic PCV2 capsid antigen but is attenuated in pigs. Future studies are warranted to evaluate the usefulness of the chimeric PCV1-2 infectious DNA clone as a genetically engineered live-attenuated vaccine against PCV2 infection and PMWS. PMID:14512571

  8. Comparison of three commercial one-dose porcine circovirus type 2 (PCV2) vaccines in a herd with concurrent circulation of PCV2b and mutant PCV2b.

    PubMed

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

    2015-05-15

    Porcine circovirus associated disease (PCVAD) occurred in a farm where pigs had been routinely vaccinated with a commercial PCV2a vaccine. A mutant PCV2b (mPCV2b) was isolated from pigs with PCVAD, perhaps implying a perceived vaccine failure. The objective of this study was to determine and compare the efficacy of 3 one-dose PCV2a vaccines of varying antigen type and dose in the same pig farm with concurrent PCV2b and mPCV2b infection based on clinical (average daily weight gain; ADWG), virological (evidence of viremia), immunological (presence of PCV2-specific neutralizing antibody; NA and interferon-? secreting cells; IFN-?-SC), and pathological (lymphoid lesion and PCV2 antigen score within lesion) evaluation. Regardless of which commercial PCV2a vaccine was used, vaccinated animals improved ADWG, and reduced the amount of PCV2b and mPCV2b load in the blood compared to unvaccinated animals. The vaccination of piglets at 3 weeks of age effectively induced higher levels of PCV2b- and mPCV2b-specific NA and IFN-?-SC compared to unvaccinated animals. A reduction in mPCV2b load in the blood coincided with the appearance of both mPCV2b-specific NA and IFN-?-SC in the vaccinated animals. The microscopic lymphoid lesions and PCV2-antigen scores within the lymph nodes were significantly lower in vaccinated animals. The perceived vaccine failure could not be explained by incomplete protection of the commercial PCV2a vaccine against mPCV2b. The results of the present study demonstrated that currently available commercial PCV2a vaccines are protective against concurrent PCV2b and mPCV2b infection based on clinical, virological, immunological, and pathological evaluations under field conditions. PMID:25790733

  9. Original article Porcine circovirus type 2 (PCV2) induces cell

    E-print Network

    Paris-Sud XI, Université de

    Original article Porcine circovirus type 2 (PCV2) induces cell proliferation, fusion, and chemokine association with viral infection in pigs. The objective of the present study was to evaluate whether porcine circovirus type 2 (PCV2) alone is able to induce functional modulation in porcine monocytic cells in vitro

  10. Influence of Maternal Antibodies on Efficacy of Porcine Circovirus Type 2 (PCV2) Vaccination To Protect Pigs from Experimental Infection with PCV2?

    PubMed Central

    Opriessnig, T.; Patterson, A. R.; Elsener, J.; Meng, X. J.; Halbur, P. G.

    2008-01-01

    Due to the ubiquitous nature of porcine circovirus type 2 (PCV2) in the pig population and the increasing use of PCV2 vaccines in breeding herds, the majority of dams have been exposed to field PCV2 or PCV2 vaccines, resulting in piglets with varied levels of passively acquired PCV2 maternal antibodies. The objective of the current research was to investigate the influence of passively acquired anti-PCV2 antibodies on PCV2 vaccine efficacy. Sixty 26-day-old pigs were divided into four groups: vaccinated pigs with no maternal PCV2 antibodies at the time of vaccination (VAC-NEG; n = 9), vaccinated pigs with maternal PCV2 antibodies at the time of vaccination (VAC-POS; n = 21), nonvaccinated pigs with no maternal antibodies at the time of challenge (NVAC-CNEG; n = 15), and nonvaccinated pigs with maternal antibodies at the time of challenge (NVAC-CPOS; n = 15). Vaccinations and challenges were performed on trial days 0 and 28, respectively, according to group designation. The pigs were monitored for clinical signs of disease daily and weighed weekly, and blood was collected weekly. All pigs were necropsied on trial day 49, and tissues were evaluated for macroscopic and microscopic lesions. Serum was evaluated using PCV2 immunoglobulin G (IgG) and PCV2 IgM enzyme-linked immunosorbent assays, quantitative PCV2 PCR, and a serum PCV2 neutralizing antibody test. In comparison to NVAC-CPOS pigs, VAC-POS animals had significantly (P < 0.01) less severe microscopic PCV2-associated lymphoid lesions and significantly (P < 0.04) reduced PCV2 genomic copies in serum following PCV2 challenge. These results indicate that vaccination with Suvaxyn PCV2 One Dose reduces viremia and prevents microscopic lesions associated with PCV2 in the presence of maternal antibodies. PMID:18094109

  11. 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.

  12. Pigs naturally exposed to porcine circovirus type 2 (PCV2) generate antibody responses capable to neutralise PCV2 isolates of different genotypes and geographic origins

    PubMed Central

    2014-01-01

    Porcine circovirus type 2 (PCV2) is the essential infectious agent for PCV2-systemic disease (PCV2-SD, formerly known as postweaning multisystemic wasting syndrome) and other pathological conditions. Recent studies indicated antigenic variability amongst different PCV2 isolates and suggested that single amino acid changes within the capsid protein determine differences in the level of neutralization by specific monoclonal antibodies. The objective of the present study was to examine the cross-reactivity of PCV2 antibodies induced in the context of a natural infection against different PCV2 isolates belonging to genotypes PCV2a and PCV2b. Sera taken from several farms from animals of varying health status (PCV2-SD and age-matched healthy pigs and a set of slaughter-aged animals) were assayed for neutralizing activity against four PCV2 isolates from both predominant genotypes (PCV2a and PCV2b) and of differing geographic origins (Europe and North-America). Results showed that most of studied pigs (79 out of 82) contained neutralizing antibodies (NA) able to neutralize all four studied viral strains. Overall, pigs had significantly higher NA titres against PCV2a than against PCV2b (P?PCV2a) than L-33-Sp-10-54 and MO/S-06 strains (PCV2b) (P?PCV2 isolates translate to functional antigenic differences in viral neutralization in vivo. PMID:24602200

  13. Effects of an Inactivated Porcine Circovirus Type 2 (PCV2) Vaccine on PCV2 Virus Shedding in Semen from Experimentally Infected Boars ?

    PubMed Central

    Seo, Hwi Won; Han, Kiwon; Kim, Duyeol; Oh, Yeonsu; Kang, Ikjae; Park, Changhoon; Jang, Hyun; Chae, Chanhee

    2011-01-01

    The objective of the present study was to determine the effect of an inactivated porcine circovirus type 2 (PCV2) vaccine on PCV2b virus shedding in the semen of experimentally infected boars by measuring the immunological response and the PCV2b DNA load in blood and semen. Twelve boars were randomly divided into three groups. The boars in group 1 (n = 4) were immunized with an inactivated PCV2 vaccine and were challenged with PCV2b. The boars in group 2 (n = 4) were only challenged with PCV2b. The boars in group 3 (n = 4) served as negative controls. The number of PCV2 genome copies of PCV2 in the serum and semen were significantly lower in vaccinated challenged boars than in nonvaccinated challenged boars at 7, 10, 14, 21, 32, 35, 42, 49, and 60 days postinoculation. The number of PCV2b genomes in the semen correlated with the number of PCV2b genomes in the blood in both vaccinated challenged (R = 0.714) and nonvaccinated challenged (R = 0.861) boars. The results of the present study demonstrate that the inactivated PCV2 vaccine significantly decreases the amount of PCV2b DNA shedding in semen from vaccinated boars after experimental infection with PCV2b. PMID:21613465

  14. Electrolyte Intake and Nonpharmacologic Blood Pressure Control

    Microsoft Academic Search

    Mark A Espeland; Shiriki Kumanyika; Carla Yunis; Beiyao Zheng; W. Mark Brown; Sharon Jackson; Alan C Wilson; Judy Bahnson

    2002-01-01

    PURPOSE: To characterize relationships between sodium and potassium intakes and blood pressure control.METHODS: We analyzed repeated 24-hour diet recalls and 24-hour urine assays from 873 elderly participants with established hypertension in a 3-year clinical trial of lifestyle interventions. Pooled estimates of electrolyte intakes were developed using hierarchical measurement error models and related to nonpharmacologic blood pressure control.RESULTS: Relative decreases in

  15. Genetic characterisation and phylogenetic analysis of PCV2 isolates from India: Indications for emergence of natural inter-genotypic recombinants.

    PubMed

    Anoopraj, R; Rajkhowa, Tridib K; Cherian, Susan; Arya, Rahul S; Tomar, Neelam; Gupta, Ashish; Ray, Pradeep K; Somvanshi, R; Saikumar, G

    2015-04-01

    Porcine circovirus type 2 (PCV2), the necessary agent in pathogenesis of porcine circovirus diseases (PCVDs), has a worldwide distribution and is considered as one of the most important emerging viral pathogens of economic importance. PCV2 has been divided into four major genotypes namely PCV2a with five clusters or subtypes (2A-2E), PCV2b with three clusters (1A-1C), PCV2c and PCV2d, based on capsid (cap) gene analysis. PCV2 genome is rapidly evolving through events of recombination and mutation. Though, PCV2a was the predominant genotype initially, PCV2b shared majority of PCV2 sequences submitted to GenBank since 2003. In India, data regarding molecular characterisation of PCV2 is scant or absent. In the present study, we thoroughly analysed genetic heterogeneity of PCV2 strains circulating in Indian pig population. The results revealed that pigs in this region harboured PCV2 viruses of different genotypes including PCV2a-2D, PCV2b-1C and PCV2d. More interestingly, two isolates (PCV2Izn-89-13 and PCV2Izn-218-13) were classified as recombinant strains. Further detailed analysis suggested that these strains evolved from inter-genotypic recombination between PCV2a-2C and PCV2b-1C genotypes within cap gene. This study reports for the first time, the emergence of recombinant PCV2 strains in the Indian pig population. PMID:25592870

  16. Phase III Randomized Study of Postradiotherapy Chemotherapy with Combination -Difluoromethylornithine-PCV versus PCV for Anaplastic Gliomas 1

    Microsoft Academic Search

    Victor A. Levin; Kenneth R. Hess; Ali Choucair; Patrick J. Flynn; Kurt A. Jaeckle; Athanassios P. Kyritsis; W. K. Alfred Yung; Michael D. Prados; Janet M. Bruner; Sandra Ictech; Mary Jo Gleason; Hyung-Woo Kim

    2003-01-01

    Purpose: In the current study, we sought to determine whether the addition of DFMO (-difluoromethyl ornithine; eflornithine), an inhibitor of ornithine decarboxylase, to a nitrosourea-based therapy procarbazine, 1-(2-chloroethyl)- 3-cyclohexyl-1-nitrosourea, vincristine (PCV) would be more effective as a postirradiation adjuvant therapy for anaplastic gliomas (AG) than PCV alone. Patients and Methods: After conventional radiation therapy, 249 AG patients were randomized to

  17. Ventilative cooling

    E-print Network

    Graça, Guilherme Carrilho da, 1972-

    1999-01-01

    This thesis evaluates the performance of daytime and nighttime passive ventilation cooling strategies for Beijing, Shanghai and Tokyo. A new simulation method for cross-ventilated wind driven airflow is presented . This ...

  18. EFFECT OF PORCINE CIRCOVIRUS TYPE 2 (PCV2) VACCINATION ON PORCINE REPRODUCTIVE AND RESPIRATORY SYNDROME VIRUS (PRRSV) AND PCV2 COINFECTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were (1) to determine if PCV2 vaccination is effective in reducing disease and lesions associated with PRRSV and PCV2 coinfection and (2) to determine if there is a difference between intradermal (ID) and intramuscular (IM) route of PCV2 vaccination. Seventy-four, 21 day...

  19. Vaccination of sows reduces the prevalence of PCV-2 viraemia in their piglets under field conditions.

    PubMed

    O'Neill, K C; Hemann, M; Giménez-Lirola, L G; Halbur, P G; Opriessnig, T

    2012-10-27

    The objectives of this study were to further understand vertical transmission of porcine circovirus type 2 (PCV-2) and the effect of dam vaccination on PCV-2 viraemia in newborn piglets. Randomly selected sows from each of two breeding herds were designated as non-vaccinated or vaccinated groups. A commercial inactivated PCV-2 vaccine was administered at weaning and 18 days later to half of the sows on each farm. At parturition, colostrum was collected from 70 dams on each farm and postsuckle (Farm 1) or presuckle blood (Farm 2) was collected from five randomly selected piglets per litter. Colostrum samples had an anti-PCV-2 antibody prevalence of 98.5 per cent (135/137) with significantly (P = 0.0039) higher concentrations in vaccinated dams. Among piglets, 43.9 per cent (301/685) were seropositive for PCV-2 and 11.7 per cent (80/686) were PCV-2 DNA-positive. All the PCV-2 DNA-positive samples were further characterised and 28 were PCV-2a, 28 PCV-2b, and five mixed PCV-2a and PCV-2b infection. The prevalence of PCV-2 DNA in piglets was lower (0.7-22.8 per cent) compared with previous studies (44.8-90 per cent) indicating a change in PCV-2 ecology likely due to wide use of vaccination. Under the study conditions, dam vaccination reduced PCV-2 viraemia in the offspring with colostrum access. PMID:22952131

  20. Industrial ventilation

    NASA Astrophysics Data System (ADS)

    Goodfellow, H. D.

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

  1. Genetic Characterization of Type 2 Porcine Circovirus (PCV2) 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 PCV1 and PCV2

    Microsoft Academic Search

    MARTIJN FENAUX; PATRICK G. HALBUR; MIKE GILL; THOMAS E. TOTH; XIANG-JIN MENG

    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.

  2. Five winters of pneumococcal serotype replacement in UK carriage following PCV introduction

    PubMed Central

    Gladstone, Rebecca A.; Jefferies, Johanna M.; Tocheva, Anna S.; Beard, Kate R.; Garley, David; Chong, Wei Wei; Bentley, Stephen D.; Faust, Saul N.; Clarke, Stuart C.

    2015-01-01

    The seven-valent pneumococcal conjugate vaccine (PCV7) was added to the UK national immunisation programme in September 2006. PCV13 replaced PCV7 in April 2010. As carriage precedes disease cases this study collected carried pneumococci from children each winter from 2006/7 to 2010/11 over PCV introduction. Conventional microbiology and whole genome sequencing were utilised to characterise pneumococcal strains. Overall prevalence of pneumococcal carriage remained stable. Vaccine serotypes (VT) decreased (p < 0.0001) with concomitant increases in non-vaccine serotypes (NVT). In winter 2010/11 only one isolate of PCV7 VT was observed (6B). PCV13 unique VTs decreased between winters immediately preceding and following PCV13 introduction (p = 0.04). Significant decreases for VTs 6B, 19F, 23F (PCV7) and 6A (PCV13) and increases for NVT 21, 23B, 33F and 35F were detected. The serotype replacement was accompanied by parallel changes in genotype prevalence for associated sequence types with clonal expansion contributing to replacement. By winter 2010/11, serotype coverage of PCV7 and PCV13 was 1% and 11% respectively. VT replacement was observed for PCV7 and PCV13 serotypes. Conjugate vaccine design and use requires continuous monitoring and revision. PMID:25776920

  3. Five winters of pneumococcal serotype replacement in UK carriage following PCV introduction.

    PubMed

    Gladstone, Rebecca A; Jefferies, Johanna M; Tocheva, Anna S; Beard, Kate R; Garley, David; Chong, Wei Wei; Bentley, Stephen D; Faust, Saul N; Clarke, Stuart C

    2015-04-21

    The seven-valent pneumococcal conjugate vaccine (PCV7) was added to the UK national immunisation programme in September 2006. PCV13 replaced PCV7 in April 2010. As carriage precedes disease cases this study collected carried pneumococci from children each winter from 2006/7 to 2010/11 over PCV introduction. Conventional microbiology and whole genome sequencing were utilised to characterise pneumococcal strains. Overall prevalence of pneumococcal carriage remained stable. Vaccine serotypes (VT) decreased (p<0.0001) with concomitant increases in non-vaccine serotypes (NVT). In winter 2010/11 only one isolate of PCV7 VT was observed (6B). PCV13 unique VTs decreased between winters immediately preceding and following PCV13 introduction (p=0.04). Significant decreases for VTs 6B, 19F, 23F (PCV7) and 6A (PCV13) and increases for NVT 21, 23B, 33F and 35F were detected. The serotype replacement was accompanied by parallel changes in genotype prevalence for associated sequence types with clonal expansion contributing to replacement. By winter 2010/11, serotype coverage of PCV7 and PCV13 was 1% and 11% respectively. VT replacement was observed for PCV7 and PCV13 serotypes. Conjugate vaccine design and use requires continuous monitoring and revision. PMID:25776920

  4. Shuttle Orbiter Atmospheric Revitalization Pressure Control Subsystem

    NASA Technical Reports Server (NTRS)

    Walleshauser, J. J.; Ord, G. R.; Prince, R. N.

    1982-01-01

    The Atmospheric Revitalization Pressure Control Subsystem (ARPCS) provides oxygen partial pressure and total pressure control for the habitable atmosphere of the Shuttle for either a one atmosphere environment or an emergency 8 PSIA mode. It consists of a Supply Panel, Control Panel, Cabin Pressure Relief Valves and Electronic Controllers. The panels control and monitor the oxygen and nitrogen supplies. The cabin pressure relief valves protect the habitable environment from overpressurization. Electronic controllers provide proper mixing of the two gases. This paper describes the ARPCS, addresses the changes in hardware that have occurred since the inception of the program; the performance of this subsystem during STS-1 and STS-2; and discusses future operation modes.

  5. ORIGINAL PAPER Porcine circovirus type 2 (PCV2) antigen localisation

    E-print Network

    Paris-Sud XI, Université de

    ORIGINAL PAPER Porcine circovirus type 2 (PCV2) antigen localisation and post-weaning multisystemic 2010 # Springer-Verlag 2010 Abstract Wild boar (Sus scrofa ssp scrofa) is a host of porcine circovirus (Sus scrofa ssp scrofa) . Immunohistochemistry. Immunofluorescence . PMWS Introduction Porcine

  6. Characterisation of PCV2 isolates from Spain, Germany and France

    Microsoft Academic Search

    Annette Mankertz; Mariano Domingo; Josep M Folch; Pierre LeCann; André Jestin; Joaquim Segalés; Barbara Chmielewicz; Juan Plana-Durán; Dirk Soike

    2000-01-01

    The new isolated circovirus variant PCV-2 is discussed to be the etiological agent of a new emerging swine disease with a variable morbidity and high lethality, postweaning multisystemic wasting syndrome (PMWS). PMWS has been diagnosed in North America and West Europe. Clinical signs include dyspnea, loss of weight, lymph node enlargement and lymphocyte depletion in lymphoid tissues. This report describes

  7. Experimental infection of colostrum deprived piglets with porcine circovirus 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) potentiates PCV2 replication

    Microsoft Academic Search

    G. M. Allan; F. McNeilly; J. Ellis; S. Krakowka; B. Meehan; I. McNair; I. Walker; S. Kennedy

    2000-01-01

    Summary.  ?Experimental infection of colostrum-deprived (CD) pigs with a combined inoculum of porcine circovirus 2 (PCV2) and porcine\\u000a reproductive and respiratory syndrome virus (PRRSV) potentiated the replication and distribution of PCV2 virus, when compared\\u000a with pigs inoculated with PCV2 alone. The replication and distribution of PRRSV in dually infected pigs was not enhanced,\\u000a when compared to pigs inoculated with PRRSV alone.

  8. 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-closure thermal models (Section 6.6). (3) To satisfy the remainder of KTI agreement TEF 2.07 (Reamer and Williams 2001b). Specifically to provide the results of post-test ANSYS modeling of the Atlas Facility forced convection tests (Section 7.1.2). This portion of the model report also serves as a validation exercise per AP-SIII.10Q, Models, for the ANSYS ventilation model. (4) To further satisfy KTI agreements RDTME 3.01 and 3.14 (Reamer and Williams 2001a) by providing the source documentation referred to in the KTI Letter Report, ''Effect of Forced Ventilation on Thermal-Hydrologic Conditions in the Engineered Barrier System and Near Field Environment'' (Williams 2002). Specifically to provide the results of the MULTIFLUX model which simulates the coupled processes of heat and mass transfer in and around waste emplacement drifts during periods of forced ventilation. This portion of the model report is presented as an Alternative Conceptual Model with a numerical application, and also provides corroborative results used for model validation purposes (Section 6.3 and 6.4).

  9. VOICE SYNTHESIS USING THE GENERALIZED PRESSURE-CONTROLLED VALVE

    E-print Network

    Smyth, Tamara

    , and the vibration of vo- cal folds in the larynx, which function as a pressure-controlled valve regulating airflowVOICE SYNTHESIS USING THE GENERALIZED PRESSURE-CONTROLLED VALVE Tamara Smyth and Alireza Fathi into the the vocal tract. This re- search explores the application of the generalized dynamic pressure-control valve

  10. Air Pressure Controlled Mass Measurement System

    NASA Astrophysics Data System (ADS)

    Zhong, Ruilin; Wang, Jian; Cai, Changqing; Yao, Hong; Ding, Jin'an; Zhang, Yue; Wang, Xiaolei

    Mass measurement is influenced by air pressure, temperature, humidity and other facts. In order to reduce the influence, mass laboratory of National Institute of Metrology, China has developed an air pressure controlled mass measurement system. In this system, an automatic mass comparator is installed in an airtight chamber. The Chamber is equipped with a pressure controller and associate valves, thus the air pressure can be changed and stabilized to the pre-set value, the preferred pressure range is from 200 hPa to 1100 hPa. In order to keep the environment inside the chamber stable, the display and control part of the mass comparator are moved outside the chamber, and connected to the mass comparator by feed-throughs. Also a lifting device is designed for this system which can easily lift up the upper part of the chamber, thus weights can be easily put inside the mass comparator. The whole system is put on a marble platform, and the temperature and humidity of the laboratory is very stable. The temperature, humidity, and carbon dioxide content inside the chamber are measured in real time and can be used to get air density. Mass measurement cycle from 1100 hPa to 200 hPa and back to 1100 hPa shows the effective of the system.

  11. Comparison of three commercial one-dose porcine circovirus type 2 (PCV2) vaccines on PCV2 shedding in semen from experimentally infected boars.

    PubMed

    Seo, Hwi Won; Han, Kiwon; Oh, Yeonsu; Kang, Ikjae; Park, Changhoon; Chae, Chanhee

    2013-05-31

    This study compared the effects of 3 different types of commercial PCV2 vaccines on PCV2 virus shedding in the semen from infected boars. Twenty-five non-PCV2 viremic and seronegative boars were randomly divided into five groups: three vaccinated and challenged groups, a non-vaccinated and challenged group, and a negative control group. The number of genomic copies of PCV2 in serum and semen samples was significantly decreased in vaccinated and challenged boars compared to non-vaccinated and challenged boars from 14 to 70 days post-inoculation (dpi). The number of PCV2 genomic copy in the semen correlated with the number of PCV2b genomic copy in the blood in vaccinated and challenged boars (r(2)=0.894-0.926, P<0.01), and non-vaccinated and challenged boars (r(2)=0.903, P<0.01). The vaccination protocol reduced the amount of PCV2 DNA shed in the semen. However, there was a significantly different amount of PCV2 DNA shed in semen among the 3 vaccinated and challenged boar groups. PMID:23465837

  12. Noninvasive ventilation after intubation and mechanical ventilation

    Microsoft Academic Search

    M. Ferrer; O. Bernadich; S. Nava; A. Torres

    2002-01-01

    Noninvasive ventilation after intubation and mechanical ventilation. M. Ferrer, O. Bernadich, S. Nava, A. Torres. #ERS Journals Ltd 2002. ABSTRACT: Patients with chronic airflow obstruction who are difficult to wean from mechanical ventilation are at increased risk of intubation-associated complications and mortality because of prolonged invasive mechanical ventilation. Noninvasive positive pressure ventilation may revert most of the pathophysiological mechanisms associated

  13. A live-attenuated and an inactivated chimeric porcine circovirus (PCV)1-2 vaccine are both effective at inducing a humoral immune response and reducing PCV2 viremia and intrauterine infection in female swine of breeding age

    PubMed Central

    Hemann, Michelle; Beach, Nathan M.; Meng, Xiang-Jin; Wang, Chong; Halbur, Patrick G.; Opriessnig, Tanja

    2014-01-01

    The objective of this pilot study was to determine the efficacy of inactivated (1 or 2 dose) and live-attenuated chimeric porcine circovirus (PCV)1-2 vaccines in sows using the PCV2-spiked semen model. Thirty-five sows were randomly divided into 6 groups: negative and positive controls, 1 dose inactivated PCV1-2 vaccine challenged (1-VAC-PCV2), 2 dose inactivated PCV1-2 vaccine challenged (2-VAC-PCV2), 1 dose live-attenuated PCV1-2 vaccine unchallenged (1-LIVE-VAC), and 1 dose live-attenuated PCV1-2 vaccine challenged (1-LIVE-VAC-PCV2). The inactivated PCV1-2 vaccine induced higher levels of PCV2-specific antibodies in dams. All vaccination strategies provided good protection against PCV2 viremia in dams, whereas the majority of the unvaccinated sows were viremic. Four of the 35 dams became pregnant: a negative control, a positive control, a 2-VAC-PCV2 sow, and a 1-LIVE-VAC-PCV2 sow. The PCV2 DNA was detected in 100%, 67%, and 29% of the fetuses obtained from the positive control, inactivated vaccinated, or live-attenuated vaccinated dams, respectively. The PCV2 antigen in hearts was only detectable in the positive control litter (23% of the fetuses). The PCV1-2 DNA was detected in 29% of the fetuses in the litter from the 1-LIVE-VAC-PCV2 dam. Under the conditions of this pilot study, both vaccines protected against PCV2 viremia in breeding age animals; however, vertical transmission was not prevented. PMID:24396175

  14. 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.

  15. 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. PMID:25631251

  16. Characterization of the leukogram in PCV2 infected germ-free pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Porcine Circovirus (PCV) is a non-enveloped, single stranded DNA virus of the Circoviridae family containing a circular genome of approximately 1.76 kb. The first isolate was recovered as a contaminant of a porcine kidney cell line in1974. This isolate, known as PCV type 1, is considered non-patho...

  17. Heat shock protein 27 is involved in PCV2 infection in PK-15 cells.

    PubMed

    Liu, Jie; Zhang, Lili; Zhu, Xuejiao; Bai, Juan; Wang, Liming; Wang, Xianwei; Jiang, Ping

    2014-08-30

    Porcine circovirus type 2 (PCV2) has been identified as the etiologic agent which causing postweaning multisystemic wasting syndrome in swine farms in the world. Some quantitative proteomic studies showed that many proteins significantly changed in PCV2-infected cells. To explore the role of cellular chaperones during PCV2 infection, cytoprotective chaperone Hsp27 was analyzed in PCV2-infected PK-15 cells in this study. The results showed that Hsp27 could up-regulate and accumulate in phosphorylated forms in the nuclear zone during PCV2 replication. Suppression of Hsp27 phosphorylation with specific chemical inhibitors or downregulation of all forms of Hsp27 via RNA interference significantly reduced the virus replication. Meanwhile, over-expression of Hsp27 enhanced PCV2 genome replication and virion production. It indicated that Hsp27 was required for PCV2 production in PK-15 cells culture. It should be helpful for understanding the mechanism of replication and pathogenesis of PCV2 and development of novel antiviral therapies in the future. PMID:24907481

  18. Enhanced protective immune response to PCV2 subunit vaccine by co-administration of recombinant porcine IFN-? in mice.

    PubMed

    Wang, Yi-Ping; Liu, Dan; Guo, Long-Jun; Tang, Qing-Hai; Wei, Yan-Wu; Wu, Hong-Li; Liu, Jian-Bo; Li, Sheng-Bin; Huang, Li-Ping; Liu, Chang-Ming

    2013-01-21

    The capsid (Cap) protein of PCV2 is the major immunogenic protein that is crucial to induce PCV2-specific neutralizing antibodies and protective immunity; thus, it is a suitable target antigen for the research and development of genetically engineered vaccines against PCV2 infection. IFN-? has exhibited potential efficacy as an immune adjuvant that enhances the immunogenicity of certain vaccines in experimental animal models. In this study, three recombinant proteins: PCV2-Cap protein, porcine IFN-? (PoIFN-?), and the fusion protein (Cap-PoIFN-?) of PCV2-Cap protein and PoIFN-? were respectively expressed in the baculovirus system, and analyzed by Western blot and indirect ELISA. Additionally, we evaluated the enhancement of the protective immune response to the Cap protein-based PCV2 subunit vaccine elicited by co-administration of PoIFN-? in mice. Vaccination of mice with the PCV2-Cap+PoIFN-? vaccine elicited significantly higher levels of PCV2-specific IPMA antibodies, neutralizing antibodies, and lymphocyte proliferative responses compared to the Cap-PoIFN-? vaccine, the PCV2-Cap vaccine, and LG-strain. Following virulent PCV2 challenge, no viraemia was detected in all immunized groups, and the viral loads in lungs of the PCV2-Cap+PoIFN-? group were significantly lower compared to the Cap-PoIFN-? group, the LG-strain group, and the mock group, but slightly lower compared to the PCV2-Cap group. These findings suggested that PoIFN-? substantially enhanced the protective immune response to the Cap protein-based PCV2 subunit vaccine, and that the PCV2-Cap+PoIFN-? subunit vaccine potentially serves as an attractive candidate vaccine for the prevention and control of PCV2-associated diseases. PMID:23219694

  19. 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-?(+) 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. PMID:24970364

  20. Prolonged response without prolonged chemotherapy: a lesson from PCV chemotherapy in low-grade gliomas.

    PubMed

    Peyre, Matthieu; Cartalat-Carel, Stéphanie; Meyronet, David; Ricard, Damien; Jouvet, Anne; Pallud, Johan; Mokhtari, Karima; Guyotat, Jacques; Jouanneau, Emmanuel; Sunyach, Marie-Pierre; Frappaz, Didier; Honnorat, Jérôme; Ducray, François

    2010-10-01

    Previous studies with temozolomide suggest that a prolonged duration of chemotherapy is important for treating low-grade gliomas (LGGs). PCV (procarbazine, CCNU, vincristine) chemotherapy has demonstrated efficacy in treating LGGs, but this therapy cannot be used for a prolonged period because of the cumulative toxicity. The aim of the present study was to evaluate the impact of first-line PCV chemotherapy on LGGs growth kinetics. The mean tumor diameter (MTD) of 21 LGGs was measured on serial magnetic resonance images before (n=13), during, and after PCV onset (n=21). During PCV treatment, a decrease in the MTD was observed in all patients. After PCV discontinuation, an ongoing decrease in MTD was observed in 20 of the 21 patients. Median duration of the MTD decrease was 3.4 years (range, 0.8-7.7) after PCV onset and 2.7 years (range, 0-7) after the end of PCV treatment with 60% of LGGs, demonstrating an ongoing and prolonged (>2 years) response despite chemotherapy no longer being administered. According to McDonald's criteria, the rates of partial and minor responses were 5% and 38% at the end of PCV but 38% and 42% at the time of maximal MTD decrease, which occurred after a median period of 3.4 years after PCV onset. These results challenge the idea that a prolonged duration of chemotherapy is necessary for treating LGGs and raise the issue of understanding the mechanisms involved in the persistent tumor volume decrease once chemotherapy is terminated. PMID:20488959

  1. [Mechanical ventilation in children

    PubMed

    Carvalho, W B

    1998-07-01

    OBJECTIVE: To make a brief review about mechanical ventilation in Pediatrics.METHODS: Review of the classification of types of mechanical ventilation, characteristics of pression and flow waves and indications for its installation. In a sequential way we discuss the various modes of ventilation (control ventilation, assisted-control ventilation, assisted ventilation, intermittent mandatory ventilation, synchronized intermittent mandatory ventilation, pressure-support ventilation) showing some advantages and disadvantages of using these modes. RESULTS: General rules for mechanical ventilation are presented, considering some specific pathologies in Pediatrics (acute respiratory distress syndrome, bronchopleural fistulae, cranial trauma, cardiac failure, neuromuscular pathology, acute asthma and in patients with acute descompensation of a cronic respiratory failure). CONCLUSIONS: Some limitations of mechanical ventilation and the possible advances in a short period are presented. PMID:14685580

  2. Building Pressure Control in VAV System with Relief Air Fan

    E-print Network

    Pang, X.; Liu, M.; Zheng, B.

    2005-01-01

    Building Pressure Control in VAV Systems with Relief Air Fan Xiufeng Pang, Mingsheng Liu, PhD, P.E., Bin Zheng University of Nebraska, Lincoln—ESL 1110 So. 67 th St, Omaha, NE, 68182 Abstract Building pressure control is critical... to energy conservation and indoor air quality by preventing excessive infiltration or exfiltration. In the supply and the return/relief fan Air Handling Unit (AHU) system, better space pressurization can be achieved when return/relief fan operates...

  3. [Patient-ventilator interaction].

    PubMed

    Gürsel, Gül; Aydo?du, Müge

    2009-01-01

    Mechanically ventilated patients interact with ventilator functions at different levels such as triggering of the ventilator, pressurization and cycling from inspiration to expiration. Patient ventilator asynchrony in any one of these phase results in fighting with ventilator, increase in work of breathing and respiratory muscle fatigue. Patient ventilator dyssynchrony occurs when gas delivery from the ventilator does not match with the neural output of the respiratory center. The clinical findings of patient-ventilator asynchrony are; use of accessory respiratory muscle, tachypnea, tachycardia, active expiration, diaphoresis and observation of asynchrony between patient respiratory effort and the ventilator waveforms. Among the patients with dynamic hyperinflation such as chronic obstructive pulmonary disease the most frequent causes of patient-ventilator asynchrony are trigger and expiratory asynchronies. In acute respiratory distress syndrome patient-ventilator asynchrony may develop due to problems in triggering or asynchrony in flow and inspiration-expiration cycle. Patient-ventilator interaction during noninvasive mechanical ventilation may be affected by the type of masks used, ventilator types, ventilation modes and parameters, humidification and sedation. Among the different patient groups it is important to know causes and solutions of patient-ventilator asynchrony problems. By this way patient will adapt ventilator and then dyspnea, ineffective respiratory effort and work of breathing may decrease subsequently. PMID:20037864

  4. 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 motivation of the patient, and the support of the family. PMID:22663966

  5. The pressure control technology of the active stressed lap

    NASA Astrophysics Data System (ADS)

    Li, Ying; Wang, Daxing

    2010-10-01

    The active stressed lap polishing technology is a kind of new polishing technology that can actively deform the lap surface to become an off-axis asphere according to different lap position on mirror surface and different angle of lap. The pressure of the lap on the mirror is an important factor affecting the grinding efficiency of the optics mirror. The active stressed lap technology using dynamic pressure control solution in the process of polishing astronomical Aspheric Mirror with faster asphericity will provide the advantage like high polishing speed and natural smooth, etc. This article puts emphases on the pressure control technology of the active stressed lap technology. It requires that the active stressed lap keeps symmetrical vertical compression on the mirrors in the process of grinding mirrors. With a background of an active stressed lap 450mm in diameter, this article gives an outline of the pressure control organization, analyzes the principle of pressure control and proposes the limitations of the present pressure control organization and the relevant solutions, designs a digital pressure controller with C32-bit RISC embedded and gives the relevant experimental test result finally.

  6. Meeting Residential Ventilation Standards

    E-print Network

    LBNL 4591E Meeting Residential Ventilation Standards Through Dynamic Control of Ventilation Systems 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

  7. Energy recovery ventilator

    Microsoft Academic Search

    S. L. Schneider; K. Dravnieks

    1985-01-01

    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

  8. Detection of PCV2 DNA by SYBR Green I-based quantitative PCR

    Microsoft Academic Search

    Zong-zhao Yang; Mudasser Habib; Jiang-bing Shuai; Wei-huan Fang

    2007-01-01

    We developed an assay for the detection and quantitation of porcine circovirus type 2 (PCV2) with the SYBR Green I-based real-time\\u000a PCR. The real-time PCR provides a broad dynamic range, detecting from 103 to 1011 copies of DNA per reaction. No cross-reactions were found in specimens containing PCV1. Because of the high sensitivity and\\u000a specificity of the assay with a

  9. 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

  10. Effect of an interferon-stimulated response element (ISRE) mutant of porcine circovirus type 2 (PCV2) on PCV2-induced pathological lesions in a porcine reproductive and respiratory syndrome virus (PRRSV) co-infection model.

    PubMed

    Ramamoorthy, S; Opriessnig, T; Pal, N; Huang, F F; Meng, X J

    2011-01-10

    Porcine circovirus type 2 (PCV2) is the primary causative agent of porcine circovirus-associated diseases (PCVAD) in swine. Coinfections of PCV2 with other swine pathogens increase the severity of PCVAD. Induction of proinflammatory cytokines by coinfecting pathogens may attribute to the exacerbation of PCVAD during coinfections. An interferon-stimulated response element (ISRE) sequence was identified in the origin of replication of PCV2 genome. To assess the role of ISRE in PCV2 pathogenesis during coinfection, an ISRE-mutant PCV2 was constructed and used to experimentally infect pigs with either ISRE mutant or wildtype PCV2 singly or in combination with porcine reproductive and respiratory syndrome virus (PRRSV). The results showed that, during early stage of infection at 14 days post-inoculation (dpi), the ISRE mutation reduced viral replication and elicited low antibody responses. However, at 28 dpi viremia in pigs infected with the ISRE-mutant was on an upward trend, and microscopic lesion scores in pigs inoculated with the ISRE-mutant were significantly more severe than in wildtype PCV2-infected pigs. Coinfection with PRRSV caused an opposite shift in the in vivo dynamics of the ISRE-mutant at 14 dpi with the lymph node histopathological lesions being significantly more severe in pigs coinfected with the ISRE-mutant PCV2 and PRRSV than in pigs coinfected with wildtype PCV2 and PRRSV. PCV2 genomic copy numbers in pigs coinfected with ISRE-mutant and PRRSV were also higher than those coinfected with wildtype PCV2 and PRRSV. The results suggested that the ISRE element in PCV2 genome may play a potential role in viral pathogenesis. PMID:20637549

  11. A Porcine Circovirus Type 2 (PCV2) Mutant with 234 Amino Acids in Capsid Protein Showed More Virulence In Vivo, Compared with Classical PCV2a/b Strain

    PubMed Central

    Guo, Longjun; Fu, Yujie; Wang, Yiping; Lu, Yuehua; Wei, Yanwu; Tang, Qinghai; Fan, Peihu; Liu, Jianbo; Zhang, Long; Zhang, Feiyan; Huang, Liping; Liu, Dan; Li, Shengbin; Wu, Hongli; Liu, Changming

    2012-01-01

    Background Porcine circovirus type 2 (PCV2) is considered to be the primary causative agent of postweaning multisystemic wasting syndrome (PMWS), which has become a serious economic problem for the swine industry worldwide. The major genotypes, PCV2a and PCV2b, are highly prevalent in the pig population and are present worldwide. However, another newly emerging PCV2b genotype mutant, which has a mutation in its ORF2-encoded capsid protein, has been sporadically present in China, as well as in other countries. It is therefore important to determine the relative virulence of the newly emerging PCV2b genotype mutant, compared with the existing PCV2a and PCV2b genotypes, and to investigate whether the newly emerging mutant virus induces more severe illness. Methodology/Principal Findings Twenty healthy, 30-day-old, commercial piglets served as controls or were challenged with PCV2a, PCV2b and the newly emerging mutant virus. A series of indexes representing different parameters were adopted to evaluate virulence, including clinical signs, serological detection, viral load and distribution, changes in immune cell subsets in the peripheral blood, and evaluation of pathological lesions. The newly emerging PCV2 mutant demonstrated more severe signs compatible with PMWS, characterized by wasting, coughing, dyspnea, diarrhea, rough hair-coat and depression. Moreover, the pathological lesions and viremia, as well as the viral loads in lymph nodes, tonsils and spleen, were significantly more severe (P<0.05) for piglets challenged with the newly emerging mutant compared with those in the groups challenged with PCV2a and PCV2b. In addition, a significantly lower average daily weight gain (P<0.05) was recorded in the group challenged with the newly emerging PCV2 mutant than in the groups challenged with the prevailing PCV2a and PCV2b. Conclusions This is believed to be the first report to confirm the enhanced virulence of the newly emerging PCV2 mutant in vivo. PMID:22829951

  12. Ear necrosis syndrome in weaning pigs associated with PCV2 infection: A case report

    PubMed Central

    Papatsiros, Vassilis

    2012-01-01

    Porcine necrotic ear syndrome (PNES) in pigs has been reported as an increasing health problem in many countries with intensive pig farming. The etiology of this disease is complex and the presumed triggering factors can be divided into infectious and non-infectious agents. The present report describes a case of Porcine Circovirus type 2 (PCV2), infection associated with lesions of PNES at the weaning stage of a farrow-to-finish pig farm. Approximately 35% of weaners (1-3 weeks after weaning) presented clinical symptoms similar to Post-weaning Multisystemic Wasting Syndrome (PMWS). About 2-3 weeks after weaning the first lesions of PNES occurred in approximately 20% of pigs, resulting in a significant health problem characterized by poor growth or severe wasting and finally mortality up to 15% in some batches. Moreover, approximately 5% of survived weaners, during growing / finishing stage, presented poor growth and secondary co-infections that lead to death. The present study based on the clinical signs, serological and pathological examinations, indicates that weaners suffered by sub-acute PCV2 infection resulting in PMWS associated with PNES. The lesions of PNES were initially observed at the same period (4-8 weeks of age) with the higher seroprevalence of PCV2 infection. Metaphylaxis of this case included intramuscular injection of florfenicol for the treatment and control of skin lesions and respiratory signs. Moreover, piglets were vaccinated against PCV2. In conclusion, sub-acute PCV2 infection could be included in triggering factors PNES in weaners. The mass vaccination against PCV2 of infected piglets might be effective in reduction of clinical signs and losses of PNES in cases of PCV2 infection associated with PNES. PMID:25610573

  13. 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.

  14. Effect of medication renewal access on blood pressure control

    Microsoft Academic Search

    Alan J. Zillich; Barry L. Carter; Michael E. Ernst; Michael W. Kelly

    2002-01-01

    Medications at the Family Medicine Clinic are renewed either by the physician during the office visit or by a clinical pharmacist via a telephone medication renewal service. This study evaluated the effect of medication renewal access on blood pressure control in an academic family medicine clinic.Age, gender, diagnosis of heart failure and\\/or diabetes were recorded for all patients seen at

  15. 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

  16. Line pressure control system for an automatic transmission

    SciTech Connect

    Sakakiyama, R

    1989-05-23

    A line pressure control system is described for an automatic transmission for a motor vehicle having an engine, a starting motor operated by closing of a starting motor switch for starting the engine, and a microcomputer supplied with voltage from a battery and controlling line pressure in a hydraulic circuit for the automatic transmission in accordance with driving condition of the motor vehicle.

  17. Saturating controllers for pressure control with an electrohydraulic servovalve

    Microsoft Academic Search

    Alexander Fink; Tarunraj Singh

    1997-01-01

    Electrohydraulic servovalves are the most commonly used control devices for hydraulic systems. However, electrohydraulic servo systems are difficult to control because they are in essence highly nonlinear. In this study, the pressure control loop including the electrohydraulic servovalve is modeled and the major nonlinearities are pointed out. A nonlinear transformation is presented to convert the system dynamics to a linear

  18. A cardiovascular model for blood pressure control systems

    Microsoft Academic Search

    P. C. A. Ang; B. W. Ang; K. Y. Zhu

    2009-01-01

    A cardiovascular model for blood pressure control system is developed in this paper. This model is used to simulate hypertensive patients in order to design control systems for regulation of blood pressure. The stability of the model is also investigated. The model can accurately represent human arterial blood pressure and therefore, the control system designed and simulated based on the

  19. Variable force solenoid pressure control for an automatic transmission

    Microsoft Academic Search

    Lemieux

    1989-01-01

    This patent describes a hydraulic pressure control circuit for an automatic transmission having fluid pressure operated clutch and brake servo. The controlling transmission consists of: a pump and a main pressure regulator valve means for establishing a regulated pressure in the control circuit; a variable force solenoid valve means for developing a pressure proportional to engine torque including a variable

  20. 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 ...

  1. Good ventilation is important

    E-print Network

    #12;Good ventilation is important Whether you're buying a new home or taking care of the one you're in now, good ventilation is important because it helps pro- tect your health and your home. Good ventilation is as critical to your comfort and safety as a reliable heating system, a smoke alarm, or a dry

  2. 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.? Confirming these findings in intervention studies is recommended. ? Energy costs of heating/cooling unoccupied classrooms statewide are modest, but a large portion occurs in relatively few classrooms.

  3. Assessing PCV2 antibodies in field pigs vaccinated with different porcine circovirus 2 vaccines using two commercial ELISA systems

    PubMed Central

    Shin, Min-Kyoung; Yoon, Seung Hyun; Kim, Myung Hwui; Lyoo, Young Soo; Suh, Seung Won

    2015-01-01

    Porcine circovirus type 2 (PCV2) is the primary causative agent for post-weaning, multisystemic, wasting syndrome. Consequently, serologic detection of and vaccination against PCV2 are important for the swine industry. Among several serological tests, the enzyme-linked immunosorbent assay (ELISA) is commonly used to measure anti-PCV2 antibody levels. In the present study, we used two commercial ELISA systems to comparatively evaluate anti-PCV2 antibodies in field pigs treated with three different PCV2 vaccines. Among a total of 517 serum samples, the results of the two ELISAs were fully concordant for 365 positive and 42 negative samples, indicating 78.7% agreement. In addition, the Pearson coefficient (0.636) indicated a moderate correlation between data from the two ELISAs. Results from the farms with pigs vaccinated with the three different PCV2 vaccines demonstrated that most of the vaccinated animals underwent seroconversion. However, the increase and duration of antibody titers varied depending on the vaccine, the presence of maternal antibodies, and the vaccination program. PCV2 serologic status and anti-PCV2 antibody levels of herds from this study could be utilized to determine the best timing for vaccination and assessing vaccination compliance. PMID:25234326

  4. Assessing PCV2 antibodies in field pigs vaccinated with different porcine circovirus 2 vaccines using two commercial ELISA systems.

    PubMed

    Shin, Min-Kyoung; Yoon, Seung Hyun; Kim, Myung Hwui; Lyoo, Young Soo; Suh, Seung Won; Yoo, Han Sang

    2015-03-01

    Porcine circovirus type 2 (PCV2) is the primary causative agent for post-weaning, multisystemic, wasting syndrome. Consequently, serologic detection of and vaccination against PCV2 are important for the swine industry. Among several serological tests, the enzyme-linked immunosorbent assay (ELISA) is commonly used to measure anti-PCV2 antibody levels. In the present study, we used two commercial ELISA systems to comparatively evaluate anti-PCV2 antibodies in field pigs treated with three different PCV2 vaccines. Among a total of 517 serum samples, the results of the two ELISAs were fully concordant for 365 positive and 42 negative samples, indicating 78.7% agreement. In addition, the Pearson coefficient (0.636) indicated a moderate correlation between data from the two ELISAs. Results from the farms with pigs vaccinated with the three different PCV2 vaccines demonstrated that most of the vaccinated animals underwent seroconversion. However, the increase and duration of antibody titers varied depending on the vaccine, the presence of maternal antibodies, and the vaccination program. PCV2 serologic status and anti-PCV2 antibody levels of herds from this study could be utilized to determine the best timing for vaccination and assessing vaccination compliance. PMID:25234326

  5. 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.

  6. Performance of ventilators for noninvasive positive pressure ventilation in children

    E-print Network

    Boyer, Edmond

    1 Performance of ventilators for noninvasive positive pressure ventilation in children Brigitte title: ventilators for noninvasive ventilation Supports and grants: The research of Brigitte Fauroux;2 Abstract The aim of the study was to evaluate the performance characteristics of all the ventilators

  7. 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 the discretization (Section 6.2.3.1), and the downstream applicability of the model results (i.e. wall heat fractions) to initialize post-closure thermal models (Section 6.6). (3) To satisfy the remainder of KTI agreement TEF 2.07 (Reamer and Williams 2001b). Specifically to provide the results of post-test ANSYS modeling of the Atlas Facility forced convection tests (Section 7.1.2). This portion of the model report also serves as a validation exercise per AP-SIII.10Q, Models, for the ANSYS ventilation model. (4) To asses the impacts of moisture on the ventilation efficiency.

  8. Ventilating the English Channel Tunnel

    SciTech Connect

    Dodge, T.M. (Raxcrest Project Management Ltd., Birmingham (United Kingdom))

    1993-10-01

    This article describes a unique ventilation system design which ensures a supply of fresh air to 95 miles of tunnels under the English Channel. The topics of the article include a description of the tunnel, a description of the equipment cooling and ventilation systems including provisions for heating of the tunnel ventilation air, ventilation system operation, and ventilation control system.

  9. 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.

  10. 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

  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. Effect of Dietary Selenium Yeast Supplementation on Porcine Circovirus Type 2 (PCV2) Infections in Mice

    PubMed Central

    Liu, Gang; Yang, Guan; Guan, Guiping; Zhang, Yuzhe; Ren, Wenkai; Yin, Jie; Aguilar, Yordan Martínez; Luo, Wei; Fang, Jun; Yu, Xinglong; Li, Tiejun; Yin, Yulong

    2015-01-01

    The present study was performed to determine the protective role of dietary selenium (Se) yeast supplementation in porcine circovirus type 2 (PCV2) infected mice. Forty-eight Kun Ming female mice were randomly assigned to Se yeast group (0.3%Se +basal diet, n = 24) and control group (basal diet, n = 24). After 3 days of adaptive feeding and 15 days treatment with the experimental feed, mice were challenged by intraperitioneal injection of PCV2 at the dosage of 2000 TCID50 (50% tissue culture infection dose, TCID50). Serum total superoxide dismutase (SOD) activity, malondialdehyde (MDA) level, tumor necrosis factor alpha (TNF-?), C-reactive protein (CRP) and interleukin-1 beta (IL-1?) levels were measured at 5, 10, 15, 20 days post infection (dpi). The PCV2 virus load in the liver, spleen and lung, and the microscopic lesions in the liver, spleen and lung also were determined on 5, 10, 15, and 20 dpi. Dietary Se yeast supplementation decreased (P?0.05) the serum levels of TNF-?, but had no significant effect on the activity of SOD and the levels of MDA, CRP and IL-1? between experimental and control groups. Dietary Se yeast supplementation had little effect on the PCV2 virus load in the liver, spleen and lung. However, mice in the selenium yeast group showed a significant decrease in microscopic lesion scores in the lung and spleen compared with those in the control group (P?0.05). These data indicate Se yeast attenuated the PCV2 infection through altering the systemic inflammation and maintaining the normal organ morphology. PMID:25723390

  13. Effect of Ventilation Strategies on

    E-print Network

    1 Effect of Ventilation Strategies on Residential Ozone Levels Iain S. Walker ventilation used to reduce concentrations of indoor-generated pollutants. When assessing the effect of deliberate ventilation on occupant health one should consider not only

  14. Pulmonary ventilation/perfusion scan

    MedlinePLUS

    V/Q scan; Ventilation/perfusion scan; Lung ventilation/perfusion scan ... A pulmonary ventilation/perfusion scan is actually two tests. They may be done separately or together. During the perfusion scan, a ...

  15. Ventilator Associated Pneumonia (VAP)

    E-print Network

    Connor, Ed

    Ventilator Associated Pneumonia (VAP) Prevention in a CVSICU ­ A CUSP based framework Ventilator Associated Pneumonia (VAP) is a serious hospital acquired condition that develops within 72 hours- associated pneumonia in intensive care: Impact of implementing a care bundle*. Critical Care Medicine, 39

  16. 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.

  17. Ventilation for humidity control: Measurements in a ventilation test house

    Microsoft Academic Search

    S. L. Palin; D. A. McIntyre; R. E. Edwards

    1996-01-01

    Three ventilation systems were installed in a recently refurbished test house: full house mechanical ventilation with heat recovery (MHVR), passive stack ventilation (PSV) and extract fans in kitchen and bathroom. Humidifiers were installed to simulate normal occupancy and behaviour of the ventilation was monitored over the winter of 1993\\/94. The test house has a low leakage rate of 3 ac

  18. Memory T cell proliferative responses and IFN-? productivity sustain long-lasting efficacy of a Cap-based PCV2 vaccine upon PCV2 natural infection and associated disease

    PubMed Central

    2014-01-01

    Porcine circovirus type 2 (PCV2) vaccination represents an important measure to cope with PCV2 infection; however, data regarding the modulation of the immune cell compartment are still limited, especially under field conditions. This study is aimed at investigating the features of the cellular immune response in conventional piglets induced by vaccination using a capsid (Cap) protein-based PCV2 vaccine compared to unvaccinated animals when exposed to PCV2 natural infection. Immune reactivity was evaluated by quantifying peripheral cell subsets involved in the anti-viral response and characterizing the interferon-gamma (IFN-?) secreting cell (SC) responsiveness both in vivo and upon in vitro whole PCV2 recall. The vaccination triggered an early and intense IFN-? secreting cell response and induced the activation of peripheral lymphocytes. The early increase of IFN-? SC frequencies resulted in a remarkable and transient tendency to increased IFN-? productivity in vaccinated pigs. In vaccinated animals, soon before the onset of infection occurred 15-16 weeks post-vaccination, the recalled PCV2-specific immune response was characterized by moderate PCV2-specific IFN-? secreting cell frequencies and augmented productivity together with reactive CD4+CD8+ memory T cells. Conversely, upon infection, unvaccinated animals showed very high frequencies of IFN-? secreting cells and a tendency to lower productivity, which paralleled with effector CD4–CD8+ cytotoxic cell responsiveness. The study shows that PCV2 vaccination induces a long-lasting immunity sustained by memory T cells and IFN-? secreting cells that potentially played a role in preventing the onset of infection; the extent and duration of this reactivity can be an important feature for evaluating the protective immunity induced by vaccination. PMID:24735253

  19. Mechanical ventilation after injury.

    PubMed

    Maung, Adrian A; Kaplan, Lewis J

    2014-01-01

    Injury is a major cause of critical illness worldwide. Severely injured patients often require mechanical ventilation not only to manage primary respiratory failure but also as adjunct to manage other conditions. Injury induces fundamental changes in multiple organ systems which directly impact ventilator management; these changes are not shared by patients without concomitant tissue injury. In this article, we review the physiologic changes after injury and discuss the impact of injury on ventilator strategies and management. We also explore the special considerations in patients with traumatic brain injury, thermal injury, blast injury or bronchopleural fistula. PMID:22956744

  20. 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.

  1. Lung Ventilation/Perfusion Scan

    MedlinePLUS

    ... the NHLBI on Twitter. What Is a Lung Ventilation/Perfusion Scan? A lung ventilation/perfusion scan, or VQ scan, is a test ... A VQ scan involves two types of scans: ventilation and perfusion. The ventilation scan shows where air ...

  2. Optimizing blood pressure control through the use of fixed combinations.

    PubMed

    Düsing, Rainer

    2010-01-01

    The majority of hypertensive patients need >or=2 antihypertensive agents to reach goal blood pressure. As an estimate, one-third of unselected hypertensive patients may be successfully treated with monotherapy, one-third may require 2 and the remaining one-third of patients will need >or=3 antihypertensive agents for effective blood pressure control. However, doctors are often hesitant to expand therapy in treated patients whose blood pressure is not lowered to goal (therapeutic inertia). Multiple-drug therapy in the majority of hypertensive patients may also represent one of several factors responsible for the low rates of adherence with chronic antihypertensive treatment. As a consequence, both US and European guidelines recommend single pill combinations to lower the number of pills needed in order to increase medication adherence and, possibly, reduce therapeutic inertia. For 2 drug combinations, the recently revised European (ESC/ESH) guidelines recommend the following options: diuretic plus either calcium channel blocker (CCB) or renin-angiotensin system (RAS) blocker (angiotensin-converting enzyme inhibitor or angiotensin receptor blocker) or CCB plus RAS-blocker. In the absence of substantial evidence, neither JNC-7 (from 2003) nor the European guidelines from 2007 give any meaningful advice on triple combination treatment. It is therefore of interest that the 2009 reappraisal of the European guidelines gives preference to the combination of a RAS blocker and a CCB plus a diuretic. On the background of the substantial number of patients requiring >or=3 drugs for blood pressure control, the recent approval of a single-pill 3-drug combination composed in accordance with the above mentioned ESC/ESH recommendations should be appreciated. PMID:20531950

  3. Optimizing blood pressure control through the use of fixed combinations

    PubMed Central

    Düsing, Rainer

    2010-01-01

    The majority of hypertensive patients need ?2 antihypertensive agents to reach goal blood pressure. As an estimate, one-third of unselected hypertensive patients may be successfully treated with monotherapy, one-third may require 2 and the remaining one-third of patients will need ?3 antihypertensive agents for effective blood pressure control. However, doctors are often hesitant to expand therapy in treated patients whose blood pressure is not lowered to goal (therapeutic inertia). Multiple-drug therapy in the majority of hypertensive patients may also represent one of several factors responsible for the low rates of adherence with chronic antihypertensive treatment. As a consequence, both US and European guidelines recommend single pill combinations to lower the number of pills needed in order to increase medication adherence and, possibly, reduce therapeutic inertia. For 2 drug combinations, the recently revised European (ESC/ESH) guidelines recommend the following options: diuretic plus either calcium channel blocker (CCB) or renin–angiotensin system (RAS) blocker (angiotensin-converting enzyme inhibitor or angiotensin receptor blocker) or CCB plus RAS-blocker. In the absence of substantial evidence, neither JNC-7 (from 2003) nor the European guidelines from 2007 give any meaningful advice on triple combination treatment. It is therefore of interest that the 2009 reappraisal of the European guidelines gives preference to the combination of a RAS blocker and a CCB plus a diuretic. On the background of the substantial number of patients requiring ?3 drugs for blood pressure control, the recent approval of a single-pill 3-drug combination composed in accordance with the above mentioned ESC/ESH recommendations should be appreciated. PMID:20531950

  4. A live-attenuated chimeric PCV2 vaccine based on subtype 2b is transmitted to contact pigs but is not upregulated by concurrent infection with PPV and PRRSV and is efficacious in a triple challenge co-infection model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to determine the safety and efficacy of a new live-attenuated chimeric PCV1/2b vaccine. Forty-six, 21-day-old, PCV2-naïve pigs were randomly assigned to one of six groups (Negative controls, positive controls, Vac-0, Vac-0-PCV2, Contact-PCV2, Vac-28-PCV2). All pigs we...

  5. 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. PMID:25457512

  6. 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.

  7. [Ventilator-associated pneumonia].

    PubMed

    Rosseau, S; Schütte, H; Suttorp, N

    2013-08-01

    Ventilator-associated pneumonia (VAP) is a severe, not entirely preventable complication of invasive ventilation. Timely and adequate antibiotic treatment is important; therefore, intensivists often initiate broad spectrum antibiotic regimens upon clinical suspicion of VAP. Criteria for the diagnosis of VAP are not perfect and a clear distinction of VAP from ventilator-associated tracheobronchitis is not always possible due to the limitations of chest x-rays in ventilated patients. The attributable mortality of VAP is likely overestimated. All these aspects increase the need to reevaluate the diagnosis of VAP on a daily basis. Microbiology data are helpful in the decision to de-escalate or stop antibiotics. The prudent use of antibiotics and implementation of a number of preventive measures are key for management of VAP in ICUs. These steps will help to minimize the development of multidrug-resistant pathogens and, in turn, may help guarantee more antibiotic options for future patients. PMID:23836252

  8. 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

  9. 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.

  10. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 2010-10-01 false Power ventilation systems except machinery space ventilation systems. 111.103-1 Section 111...Systems § 111.103-1 Power ventilation systems except machinery space ventilation systems. Each power ventilation...

  11. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 false Power ventilation systems except machinery space ventilation systems. 111.103-1 Section 111...Systems § 111.103-1 Power ventilation systems except machinery space ventilation systems. Each power ventilation...

  12. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 2012-10-01 false Power ventilation systems except machinery space ventilation systems. 111.103-1 Section 111...Systems § 111.103-1 Power ventilation systems except machinery space ventilation systems. Each power ventilation...

  13. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 2011-10-01 false Power ventilation systems except machinery space ventilation systems. 111.103-1 Section 111...Systems § 111.103-1 Power ventilation systems except machinery space ventilation systems. Each power ventilation...

  14. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 false Power ventilation systems except machinery space ventilation systems. 111.103-1 Section 111...Systems § 111.103-1 Power ventilation systems except machinery space ventilation systems. Each power ventilation...

  15. 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).

  16. 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).

  17. Variable versus conventional lung protective mechanical ventilation during open abdominal surgery: study protocol for a randomized controlled trial

    PubMed Central

    2014-01-01

    Background General anesthesia usually requires mechanical ventilation, which is traditionally accomplished with constant tidal volumes in volume- or pressure-controlled modes. Experimental studies suggest that the use of variable tidal volumes (variable ventilation) recruits lung tissue, improves pulmonary function and reduces systemic inflammatory response. However, it is currently not known whether patients undergoing open abdominal surgery might benefit from intraoperative variable ventilation. Methods/Design The PROtective VARiable ventilation trial (‘PROVAR’) is a single center, randomized controlled trial enrolling 50 patients who are planning for open abdominal surgery expected to last longer than 3 hours. PROVAR compares conventional (non-variable) lung protective ventilation (CV) with variable lung protective ventilation (VV) regarding pulmonary function and inflammatory response. The primary endpoint of the study is the forced vital capacity on the first postoperative day. Secondary endpoints include further lung function tests, plasma cytokine levels, spatial distribution of ventilation assessed by means of electrical impedance tomography and postoperative pulmonary complications. Discussion We hypothesize that VV improves lung function and reduces systemic inflammatory response compared to CV in patients receiving mechanical ventilation during general anesthesia for open abdominal surgery longer than 3 hours. PROVAR is the first randomized controlled trial aiming at intra- and postoperative effects of VV on lung function. This study may help to define the role of VV during general anesthesia requiring mechanical ventilation. Trial registration Clinicaltrials.gov NCT01683578 (registered on September 3 3012). PMID:24885921

  18. Natural ventilation generates building form

    E-print Network

    Chen, Shaw-Bing

    1996-01-01

    Natural ventilation is an efficient design strategy for thermal comfort in hot and humid climates. The building forms can generate different pressures and temperatures to induce natural ventilation. This thesis develops a ...

  19. Innovative Energy Efficient Industrial Ventilation

    E-print Network

    Litomisky, A.

    2005-01-01

    This paper was written to describe an innovative “on-demand” industrial ventilation system for woodworking, metalworking, food processing, pharmaceutical, chemical, and other industries. Having analyzed existing industrial ventilation in 130...

  20. 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.

  1. RESIDENTIAL VENTILATION AND ENERGY CHARACTERISTICS*

    E-print Network

    RESIDENTIAL VENTILATION AND ENERGY CHARACTERISTICS* Max Sherman Nance Matson Energy Performance Berkeley, California The role of ventilation in the housing stock is to provide fresh air and to dilute to provide this ventilation service, either directly for moving the air or indirectly for conditioning

  2. 3, 805826, 2006 Ventilation under

    E-print Network

    Paris-Sud XI, Université de

    OSD 3, 805­826, 2006 Ventilation under global warming A. Gnanadesikan et al. Title Page Abstract ocean ventilation change under global warming? A. Gnanadesikan 1 , J. L. Russell 2 , and F. Zeng 3 1­826, 2006 Ventilation under global warming A. Gnanadesikan et al. Title Page Abstract Introduction

  3. The International Journal of Ventilation

    E-print Network

    California at Davis, University of

    The International Journal of Ventilation Volume 12 Number 4 ISSN 1473 - 3315 March 2014 Contents A and Mróz T 391 #12;International Journal of Ventilation ISSN 1473-3315 Volume 12 No 4 March 2014 air quality and reducing energy required for heating, cooling, and ventilation. One application

  4. 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.

  5. 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.

  6. RESIDENTIAL VENTILATION STUDY

    EPA Science Inventory

    This project evaluated the effectiveness, first costs and operational costs of various types of residential ventilation systems in three different climates in the U.S. The Agency, through its Energy Star Program, recommends that builders construct homes that are energy efficient ...

  7. A proposal on porcine circovirus type 2 (PCV2) genotype definition and their relation with postweaning multisystemic wasting syndrome (PMWS) occurrence

    Microsoft Academic Search

    L. Grau-Roma; E. Crisci; M. Sibila; S. López-Soria; M. Nofrarias; M. Cortey; L. Fraile; A. Olvera; J. Segalés

    2008-01-01

    Porcine circovirus type 2 (PCV2) is the essential infectious agent of postweaning multisystemic wasting syndrome (PMWS). Despite first sequencing studies did not find any association between PCV2 sequences and PMWS occurrence, recent works have suggested the opposite. In the present study, 87 open reading frame 2 (ORF2) sequences obtained from pigs with different clinical conditions and coming from farms with

  8. 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 logical place to provide leadership. This leadership has been demonstrated most recently by the publication of the first nationally recognized standard on ventilation in homes, ASHRAE Standard 62.2-2003, which builds on work that has been part of ASHRAE for many years and will presumably continue. Homeowners and occupants, which includes virtually all of us, will benefit from the application of Standard 62.2 and use of the top ten list. This activity is exactly the kind of benefit to society that the founders of ASHRAE envisioned and is consistent with ASHRAE's mission and vision. ASHRAE members should be proud of their Society for taking leadership in residential ventilation.

  9. Spread like a wildfire--the omnipresence of porcine circovirus type 2 (PCV2) and its ever-expanding association with diseases in pigs.

    PubMed

    Meng, Xiang-Jin

    2012-03-01

    The discovery of porcine circovirus type 2 (PCV2) in 1998 initiated intensive research on arguably the most economically important pathogen facing the global swine industry today. PCV2 infection is now widespread worldwide, and increasing numbers of disease conditions have been linked to PCV2 infection in pigs. In this special issue of Virus Research, leading experts in the field review the history, epidemiology, transmission, clinical and pathological features, immunology, pathogenesis, molecular biology and vaccine development of PCV2 and porcine circovirus associated disease (PCVAD). In addition, circovirus-like DNA sequences recently identified from humans and other animal species and their biological significances are also reviewed. The articles in this special issue identify gaps in current PCV2 research and offer insights for the direction of future research. PMID:22192532

  10. The effects of inverse ratio ventilation on intracranial pressure: a preliminary report

    Microsoft Academic Search

    J. P. Clarke

    1997-01-01

    Objective: To determine the effects of pressure control inverse ratio ventilation [PC-IRV], as compared with volume controlled normal\\u000a ratio ventilation [VC], on the intracranial pressure [ICP] of patients with severe head injury.\\u000a \\u000a \\u000a \\u000a Design: A prospective study with unblinded intervention.\\u000a \\u000a \\u000a \\u000a \\u000a \\u000a Setting: The Intensive Therapy Unit of a base hospital.\\u000a \\u000a \\u000a \\u000a \\u000a \\u000a Patients and participants: Nine cases of head injury requiring mechanical ventilation and

  11. Harnessing natural ventilation benefits.

    PubMed

    O'Leary, John

    2013-04-01

    Making sure that a healthcare establishment has a good supply of clean fresh air is an important factor in keeping patients, staff, and visitors, free from the negative effects of CO2 and other contaminants. John O'Leary of Trend Controls, a major international supplier of building energy management solutions (BEMS), examines the growing use of natural ventilation, and the health, energy-saving, and financial benefits, that it offers. PMID:23678661

  12. Lightweight ventilated facade prototype: acoustic performance evaluation when the ventilation surface of

    E-print Network

    Boyer, Edmond

    Lightweight ventilated facade prototype: acoustic performance evaluation when the ventilation Conference 23-27 April 2012, Nantes, France 3801 #12;1. INTRODUCTION Lightweight ventilated facades cavity is almost totally open, fully ventilated and not very wide. Therefore, its contribution

  13. A model of psychosocial and cultural antecedents of blood pressure control.

    PubMed Central

    Bosworth, Hayden B.; Oddone, Eugene Z.

    2002-01-01

    Hypertension is a major modifiable risk factor for stroke, congestive heart failure, and end-stage renal disease. Hypertension is particularly prevalent and deadly among African Americans. Effective treatment for hypertension has been available for decades, yet only one fourth of all individuals have their blood pressure under control. Despite the potential impact of hypertension, interventions to improve control have had limited success. We present a model of how to understand antecedents of blood pressure control according to three interrelated categories: patient characteristics, social and cultural environment, and medical environment. This theoretical paper was conducted using a literature review and a model to explain psychosocial antecedents of blood pressure control is presented. We conclude that improved understanding of important antecedents of blood pressure control coupled with technological advances, such as tailored interventions, provide clinicians with a tool that may lead to improved blood pressure control. These interventions will require the involvement of clinicians and consideration of sociocultural factors to be successful. PMID:11991336

  14. 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 ... org and strokeassociation.org Share Related Images Blood Pressure Check (2) copyright American Heart Association Download (552. ...

  15. 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...

  16. 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…

  17. Pretest Predictions for Ventilation Tests

    SciTech Connect

    Y. Sun; H. Yang; H.N. Kalia

    2007-01-17

    The objective of this calculation is to predict the temperatures of the ventilating air, waste package surface, concrete pipe walls, and insulation that will be developed during the ventilation tests involving various test conditions. The results will be used as input to the following three areas: (1) Decisions regarding testing set-up and performance. (2) Assessing how best to scale the test phenomena measured. (3) Validating numerical approach for modeling continuous ventilation. The scope of the calculation is to identify the physical mechanisms and parameters related to thermal response in the ventilation tests, and develop and describe numerical methods that can be used to calculate the effects of continuous ventilation. Sensitivity studies to assess the impact of variation of linear power densities (linear heat loads) and ventilation air flow rates are included. The calculation is limited to thermal effect only.

  18. Pulmonary complications of mechanical ventilation.

    PubMed

    Sandur, S; Stoller, J K

    1999-06-01

    Although life-saving, mechanical ventilation may be associated with many complications, including consequences of positive intrathoracic pressure, the many aspects of volutrauma, and adverse effects of intubation and tracheostomy. Optimal ventilatory care requires implementing mechanical ventilation with attention to minimizing adverse hemodynamic effects, averting volutrauma, and effecting freedom from mechanical ventilation as quickly as possible so as to minimize the risk of airway complications. PMID:10386254

  19. Impact of porcine circovirus type 2 (PCV2) vaccination on boar semen quality and quantity using two different vaccines.

    PubMed

    Caspari, K; Henning, H; Schreiber, F; Maass, P; Gössl, R; Schaller, C; Waberski, D

    2014-09-01

    Porcine circovirus type-2 (PCV2) is widespread in domestic pig populations. It can be shed with boar semen, but the role boars have in epidemiology is still unclear. Vaccinating boars against PCV2 can reduce disease and virus load in semen, but may have unwanted side effects, that is, impairment of spermatogenesis. Therefore, the aim of this study was to investigate the effect and impact of two different PCV2 vaccines on boar semen quality and quantity. Healthy normospermic Large White boars in three groups of 12 each were vaccinated with either Circovac, Ingelvac CircoFLEX, or received NaCl. Eight ejaculates were collected starting 1 week after vaccination and assessed for quantitative traits. In general, sperm quantity and quality parameters did not change due to the vaccination (P > 0.05). Only DNA integrity between the Circovac and control group was P < 0.05 but remained at a low level (<2%). One boar showed clinical signs with body temperature up to 39.9 °C and went off feed. For this animal, a clear relation between vaccination, fever period, and impaired sperm quality could be observed. The results indicate that both vaccines did not have a major impact on sperm quality or quantity. Therefore, vaccination of boars against PCV2 seems to be feasible. However, one boar treated with the oil-based vaccine showed a temporarily impaired semen quality after elevated body temperature after vaccination. Thus, possible systemic reactions and the subsequent impact on sperm quality should be taken into account when choosing a PCV2 vaccine for boars. PMID:24954420

  20. Laboratory Ventilation SafetyLaboratory Ventilation Safety J. Scott WardJ. Scott Ward

    E-print Network

    Farritor, Shane

    Laboratory Ventilation SafetyLaboratory Ventilation Safety J. Scott WardJ. Scott Ward #12;In 1925. Labconco CorporationLabconco Corporation #12;Laboratory VentilationLaboratory Ventilation #12;Laboratory Ventilation ProductsLaboratory Ventilation Products #12;History of Fume HoodsHistory of Fume Hoods Thomas

  1. Ventilated oscillatory boundary layers

    NASA Astrophysics Data System (ADS)

    Conley, Daniel C.; Inman, Douglas L.

    1993-02-01

    A combination of field and laboratory experiments are made in order to expand our knowledge of naturally occurring oscillatory boundary layers. Chapter 1 describes field observations of the development of wave driven boundary layers at the fluid sediment interface. Under the crest of the wave, this development can be idealized as an identifiable sequence of three parts. The latter parts of this development are never observed to occur under the trough of the wave despite similarities in wave orbital velocity and acceleration. It is proposed that wave induced boundary ventilation, the oscillatory flow through the surface of a permeable bed, may be responsible for this apparent developmental asymmetry. In chapter 2, a laboratory study is presented of ventilated oscillatory boundary layers. These are boundary layers arising from a flow which oscillates parallel to a permeable bed which is subject to oscillating percolation of the same frequency as the bed parallel flow. Measurements of boundary layer velocities, bed stress and turbulent flow properties are presented. It is observed that suction (flow into the bed) enhances the near bed velocities and bed stress while injection (flow out of the bed) leads to a reduction in these quantities. As the ventilated oscillatory boundary layer experiences both these phenomena in one full cycle, the result is a net stress and a net boundary layer velocity in an otherwise symmetric flow. While production of turbulence attributable to injection is enhanced, the finite time required for this to occur leads to greater vertically averaged turbulence in the suction half cycle. Turbulence generated in the suction half cycle is maintained in a compact layer much closer to the bed. These effects appear to hold for Re ranging from 10(exp 5) to 10(exp 6) and for oscillations other than sinusoidal.

  2. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Ventilation systems. 252.9 Section 252...SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever the ventilation system is not fully...

  3. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation. 194.10-25 Section 194.10-25...MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. ...be provided with natural or mechanical ventilation. Design calculations shall be...

  4. 46 CFR 194.20-5 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation. 194.20-5 Section 194...or Storerooms § 194.20-5 Ventilation. (a) Chemical storerooms shall be equipped with a power ventilation system of exhaust type. The...

  5. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Crawlspace ventilation. 3285.505 Section 3285.505...Features § 3285.505 Crawlspace ventilation. (a) A crawlspace with skirting must be provided with ventilation openings. The minimum net area...

  6. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation. 194.10-25 Section 194.10-25...MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. ...be provided with natural or mechanical ventilation. Design calculations shall be...

  7. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Ventilation systems. 252.9 Section 252...SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever the ventilation system is not fully...

  8. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Ventilation systems. 252.9 Section 252...SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever the ventilation system is not fully...

  9. 30 CFR 57.8520 - Ventilation plan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Ventilation plan. 57.8520 Section 57.8520...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8520 Ventilation plan. A plan of the mine...

  10. 30 CFR 57.8520 - Ventilation plan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Ventilation plan. 57.8520 Section 57.8520...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8520 Ventilation plan. A plan of the mine...

  11. JAMA Patient Page: Ventilator-Associated Pneumonia

    MedlinePLUS

    ... a person who is being assisted by mechanical ventilation (a breathing machine), is a serious and life- ... associated pneumonia are already critically ill (requiring mechanical ventilation), the death rate from ventilator-associated pneumonia is ...

  12. 46 CFR 194.20-5 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation. 194.20-5 Section 194...or Storerooms § 194.20-5 Ventilation. (a) Chemical storerooms shall be equipped with a power ventilation system of exhaust type. The...

  13. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Crawlspace ventilation. 3285.505 Section 3285.505...Features § 3285.505 Crawlspace ventilation. (a) A crawlspace with skirting must be provided with ventilation openings. The minimum net area...

  14. Air Distribution Effectiveness for Different Mechanical Ventilation

    E-print Network

    LBNL-62700 Air Distribution Effectiveness for Different Mechanical Ventilation Systems Max H Effectiveness for Different Mechanical Ventilation Systems Max H. Sherman and Iain S. Walker Lawrence Berkeley National Laboratory, USA ABSTRACT The purpose of ventilation is to dilute indoor contaminants

  15. 46 CFR 194.20-5 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Ventilation. 194.20-5 Section 194...or Storerooms § 194.20-5 Ventilation. (a) Chemical storerooms shall be equipped with a power ventilation system of exhaust type. The...

  16. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation. 194.10-25 Section 194.10-25...MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. ...be provided with natural or mechanical ventilation. Design calculations shall be...

  17. 30 CFR 57.8520 - Ventilation plan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Ventilation plan. 57.8520 Section 57.8520...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8520 Ventilation plan. A plan of the mine...

  18. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Ventilation systems. 252.9 Section 252...SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever the ventilation system is not fully...

  19. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Crawlspace ventilation. 3285.505 Section 3285.505...Features § 3285.505 Crawlspace ventilation. (a) A crawlspace with skirting must be provided with ventilation openings. The minimum net area...

  20. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation. 194.10-25 Section 194.10-25...MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. ...be provided with natural or mechanical ventilation. Design calculations shall be...

  1. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Ventilation systems. 252.9 Section 252...SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever the ventilation system is not fully...

  2. 46 CFR 194.20-5 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation. 194.20-5 Section 194...or Storerooms § 194.20-5 Ventilation. (a) Chemical storerooms shall be equipped with a power ventilation system of exhaust type. The...

  3. 30 CFR 57.8520 - Ventilation plan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Ventilation plan. 57.8520 Section 57.8520...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8520 Ventilation plan. A plan of the mine...

  4. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Crawlspace ventilation. 3285.505 Section 3285.505...Features § 3285.505 Crawlspace ventilation. (a) A crawlspace with skirting must be provided with ventilation openings. The minimum net area...

  5. 46 CFR 194.20-5 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation. 194.20-5 Section 194...or Storerooms § 194.20-5 Ventilation. (a) Chemical storerooms shall be equipped with a power ventilation system of exhaust type. The...

  6. 30 CFR 57.8520 - Ventilation plan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Ventilation plan. 57.8520 Section 57.8520...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8520 Ventilation plan. A plan of the mine...

  7. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Crawlspace ventilation. 3285.505 Section 3285.505...Features § 3285.505 Crawlspace ventilation. (a) A crawlspace with skirting must be provided with ventilation openings. The minimum net area...

  8. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Ventilation. 194.10-25 Section 194.10-25...MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. ...be provided with natural or mechanical ventilation. Design calculations shall be...

  9. 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.

  10. Impact of 13-valent pneumococcal conjugate vaccine (PCV13) in a pandemic similar to the 2009 H1N1 in the United States

    PubMed Central

    2013-01-01

    Background High rates of bacterial coinfection in autopsy data from the 2009 H1N1 influenza (“flu”) pandemic suggest synergies between flu and pneumococcal disease (PD) during pandemic conditions, and highlight the importance of interventions like the 13-valent pneumococcal conjugate vaccine (PCV13) that may mitigate the impact of a pandemic. Methods We used a decision-analytic model, estimated from published sources, to assess the impact of pediatric vaccination with PCV13 versus the 7-valent vaccine (PCV7) on PD incidence and mortality in a normal flu season (10% flu incidence) and in a pandemic similar to 2009-2010 H1N1 (20% flu incidence, mild virulence, high impact in children). Both direct and indirect (herd) effects against PD were considered. Effectiveness of PCV13 was extrapolated from observed PCV7 data, using assumptions of serotype prevalence and PCV13 protection against the 6 serotypes not in PCV7. To simulate 2009–2010 H1N1, autopsy data were used to estimate the overall proportion of flu deaths with bacterial coinfections. By assuming that increased risk of death during the pandemic occurred among those with comorbidity (using obesity as proxy) and bacterial coinfections primarily due to S. pneumoniae or S. aureus, we estimated the proportion co-infected among all (fatal and non-fatal) flu cases (7.6% co-infected with any organism; 2.2% with S. pneumoniae). PD incidence, mortality, and total healthcare costs were evaluated over a 1-year horizon. Results In a normal flu season, compared to PCV7, PCV13 is expected to prevent an additional 13,400 invasive PD (IPD) cases, 399,000 pneumonia cases, and 2,900 deaths, leading to cost savings of $472 M. In a pandemic similar to 2009–2010 H1N1, PCV13 would prevent 22,800 IPD cases, 872,000 pneumonia cases, and 3,700 deaths, resulting in cost savings of $1.0 B compared to PCV7. Conclusions In a flu pandemic similar to the 2009–2010 H1N1, protection against the 6 additional serotypes in PCV13 would likely be effective in preventing pandemic-related PD cases, mortality, and associated costs. PMID:23687999

  11. Reverse ventilation--perfusion mismatch

    SciTech Connect

    Palmaz, J.C.; Barnett, C.A.; Reich, S.B.; Krumpe, P.E.; Farrer, P.A.

    1984-01-01

    Patients having lobar airway obstruction or consolidation usually have decreases of both ventilation and perfusion on lung scans. We report three patients in whom hypoxic vasoconstriction was apparently incomplete, resulting in a ''reversed'' ventilation-perfusion mismatch. Perfusion of the hypoxic lobe on the radionuclide scan was associated with metabolic alkalosis, pulmonary venous and pulmonary arterial hypertension in these patients.

  12. 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.

  13. Nocturnal noninvasive ventilation.

    PubMed

    Ozsancak, Aylin; D'Ambrosio, Carolyn; Hill, Nicholas S

    2008-05-01

    Nocturnal noninvasive ventilation (NNV), the provision of ventilatory assistance via a noninvasive interface mainly during sleep, has assumed an important role in the management of chronic hypoventilatory syndromes. This review focuses on recent developments related to the use of NNV to treat various forms of chronic respiratory failure or insufficiency. In the past, NNV has been used mainly to treat respiratory insufficiency in patients with neuromuscular disease (NMD) or chest wall deformity; it should be instituted when these patients have orthopnea or daytime symptoms associated with nocturnal hypoventilation. An emerging application is to treat obesity-hypoventilation syndrome, particularly in continuous positive airway pressure (CPAP) failures. Additionally, it has a role in managing some patients with obstructive sleep apnea who are hypoventilating or find the lower expiratory pressure with bilevel positive pressure ventilators more tolerable than with CPAP alone. NNV to treat severe, stable COPD remains controversial, although a subgroup of patients with hypercapnea and sleep-disordered breathing (SDB) seems most likely to respond favorably. NNV to treat central SDB in patients with congestive heart failure continues to be investigated. Recent findings from a Canadian CPAP trial were disappointing, but preliminary results on a novel adaptive NNV mode are promising. PMID:18460530

  14. 46 CFR 153.312 - Ventilation system standards.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...ft) from openings into or ventilation intakes for, accommodation or service spaces. (b) A ventilation system must not recycle vapors from ventilation discharges. (c) Except for the space served by the ventilation duct, a ventilation duct...

  15. 30 CFR 75.330 - Face ventilation control devices.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Face ventilation control devices. 75.330...COAL MINES Ventilation § 75.330 Face ventilation control devices. (a) Brattice cloth, ventilation tubing and other face ventilation control devices shall be...

  16. 30 CFR 75.330 - Face ventilation control devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Face ventilation control devices. 75.330...COAL MINES Ventilation § 75.330 Face ventilation control devices. (a) Brattice cloth, ventilation tubing and other face ventilation control devices shall be...

  17. 30 CFR 75.330 - Face ventilation control devices.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Face ventilation control devices. 75.330...COAL MINES Ventilation § 75.330 Face ventilation control devices. (a) Brattice cloth, ventilation tubing and other face ventilation control devices shall be...

  18. 30 CFR 75.330 - Face ventilation control devices.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Face ventilation control devices. 75.330...COAL MINES Ventilation § 75.330 Face ventilation control devices. (a) Brattice cloth, ventilation tubing and other face ventilation control devices shall be...

  19. 30 CFR 75.330 - Face ventilation control devices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Face ventilation control devices. 75.330...COAL MINES Ventilation § 75.330 Face ventilation control devices. (a) Brattice cloth, ventilation tubing and other face ventilation control devices shall be...

  20. Efficacy of a reformulated inactivated chimeric PCV1-2 vaccine based on clinical, virological, pathological and immunological examination under field conditions.

    PubMed

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

    2012-10-19

    Inactivated chimeric porcine circovirus (PCV) 1-2 vaccine was initially taken off the market due to concerns that the vaccine virus was not killed and thus further replicated and spread in the pig population. In August 2011, a reformulated inactivated chimeric PCV1-2 vaccine re-entered the market. The efficacy of the reformulated inactivated chimeric PCV1-2 vaccine was evaluated under field conditions for registration as recommended by the Republic of Korea's Animal, Plant & Fisheries Quarantine & Inspection Agency. Three farms were selected based on their history of postweaning multisystemic wasting syndrome (PMWS). On each farm, a total of 50 3-week-old pigs were randomly allocated to one of two treatment groups: (i) vaccinated at 3 weeks of age and (ii) non-vaccinated. Clinical examination indicated that vaccinated animals displayed an improved average daily weight gain (672.2g/day vs. 625g/day; difference of +47.3g/day; P<0.05) and a reduced time to market (177 days vs. 183 days; difference of -6 days; P<0.05). Virological examination indicated that vaccinated animals displayed a reduced PCV2 load in the blood and nasal swabs compared to non-vaccinated animals. Pathological examination indicated that vaccination of pigs against PCV2 effectively reduced the number of PMWS-associated microscopic lesions and the PCV2 load in lymphoid tissues compared to non-vaccinated animals in the 3 herds. Immunological examination indicated that vaccinated animals induced PCV2-specific neutralizing antibodies (NA) and interferon-?-secreting cells (IFN-?-SCs). A reduction in the PCV2 load in the blood coincided with the appearance of both PCV2-specific NA and IFN-?-SCs in the vaccinated animals. The number of CD4(+) cells was decreased in non-vaccinated animals compared to vaccinated animals. The reformulated inactivated chimeric PCV1-2 vaccine seems to be very effective in controlling PCV2 infection based on clinical, virological, pathological, and immunological evaluations under field conditions. PMID:22963801

  1. Cardiac gated ventilation

    SciTech Connect

    Hanson, C.W. III [Hospital of the Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. Anesthesia; Hoffman, E.A. [Univ. of Iowa College of Medicine, Iowa City, IA (United States). Div. of Physiologic Imaging

    1995-12-31

    There are several theoretic advantages to synchronizing positive pressure breaths with the cardiac cycle, including the potential for improving distribution of pulmonary and myocardial blood flow and enhancing cardiac output. The authors evaluated the effects of synchronizing respiration to the cardiac cycle using a programmable ventilator and electron beam CT (EBCT) scanning. The hearts of anesthetized dogs were imaged during cardiac gated respiration with a 50 msec scan aperture. Multi slice, short axis, dynamic image data sets spanning the apex to base of the left ventricle were evaluated to determine the volume of the left ventricular chamber at end-diastole and end-systole during apnea, systolic and diastolic cardiac gating. The authors observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a non-failing model of the heart.

  2. 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.

  3. 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.

  4. 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.

  5. Cholesterol and other cardiovascular risk factors in a working population in Ile-De-France (France): First results of the PCV-METRA study

    Microsoft Academic Search

    D. Laurier; N. P. Chau; P. Segond

    1992-01-01

    In 1989, the French PCV-METRA Group (PCV-METRA = Prévention Cardio-Vasculaire en Médecine du Travail) started a large prospective survey of cardiovascular (CDV) morbidity and mortality and of CVD risk factors, especially cholesterol, in a working population in Ile-de-France, a region including Paris. This report presents the first results of this study, based on a sample of 5758 men and 2603

  6. New back-pressure control system improving the annual performance of scroll compressors

    SciTech Connect

    Tsubono, Isamu; Takebayashi, Masahiro; Hayase, Isao [Hitachi Ltd., Tsuchiura, Ibaraki (Japan). Mechanical Engineering Research Lab.; Inaba, Koichi; Sekiguchi, Koichi; Shimada, Atsushi [Hitachi Ltd., Ohiramachi, Tochigi (Japan). Refrigeration and Air-Conditioning Div.

    1998-10-01

    The performance of a compressor using the back-pressure control system discussed here is much better than that of a conventional compressor, especially under the cooling half-load condition at a low speed and compression ratio. Nearly optimum performance is obtained under all operating conditions by keeping the back pressure at a level that is a constant amount above the suction pressure. This reduces friction at the sliding portion between the orbiting and fixed scrolls, and eliminating the back-pressure holes decreases the compression loss due to the breathing action. This back-pressure control system greatly improves the annual performance (reduces annual energy consumption) of household air conditioners.

  7. 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-1? 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-1?. 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-? 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-1?, IL-4, IL-6, IL-10, IL-12, IFN-?, MIP-1, TNF-?, 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

  8. 14 CFR 23.831 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Ventilation. 23.831 Section 23.831 Aeronautics...Cargo Accommodations § 23.831 Ventilation. (a) Each passenger and crew...adversely affect the ventilating air, the ventilation system must provide reasonable...

  9. 14 CFR 23.831 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Ventilation. 23.831 Section 23.831 Aeronautics...Cargo Accommodations § 23.831 Ventilation. (a) Each passenger and crew...adversely affect the ventilating air, the ventilation system must provide reasonable...

  10. Laboratory Ventilation Management Ralph Stuart, CHO

    E-print Network

    Pawlowski, Wojtek

    Laboratory Ventilation Management Program Ralph Stuart, CHO Ellen Sweet, Laboratory Ventilation Specialist Cornell Department of Environmental Health and Safety 3/29/2013 #12;Laboratory Ventilation.1.2 Design and Construction Standards 10 7.1.3 Carbon Dioxide Ventilation Effectiveness Protocol 10 7.2 Job

  11. Ventilation Based on ASHRAE 62.2

    E-print Network

    Indoor Ventilation Based on ASHRAE 62.2 Arnold Schwarzenegger Governor California Energy Commission Ventilation (ASHRAE 62.2) Minimum Best Practices Guide - Exhaust-Only Ventilation Introduction: The California/ASHRAE Standard 62.2-2007, Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings (ASHRAE

  12. 46 CFR 111.15-10 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation. 111.15-10 Section 111.15-10...and Installation § 111.15-10 Ventilation. (a) General. Each room...accumulation of flammable gas. (b) Power ventilation. If power ventilation is...

  13. 46 CFR 111.15-10 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation. 111.15-10 Section 111.15-10...and Installation § 111.15-10 Ventilation. (a) General. Each room...accumulation of flammable gas. (b) Power ventilation. If power ventilation is...

  14. 46 CFR 111.15-10 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Ventilation. 111.15-10 Section 111.15-10...and Installation § 111.15-10 Ventilation. (a) General. Each room...accumulation of flammable gas. (b) Power ventilation. If power ventilation is...

  15. 46 CFR 111.15-10 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation. 111.15-10 Section 111.15-10...and Installation § 111.15-10 Ventilation. (a) General. Each room...accumulation of flammable gas. (b) Power ventilation. If power ventilation is...

  16. 46 CFR 111.15-10 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation. 111.15-10 Section 111.15-10...and Installation § 111.15-10 Ventilation. (a) General. Each room...accumulation of flammable gas. (b) Power ventilation. If power ventilation is...

  17. Humidity as a Control Parameter for Ventilation

    Microsoft Academic Search

    Alireza Afshari; Niels C. Bergsøe

    2003-01-01

    The objective of this study was to develop energy efficient ventilation strategies that will provide both a healthy and comfortable indoor climate and reduce energy consumption compared to present ventilation standards. Humidity was used as a control parameter for the ventilation. Four different ventilation strategies were tested in a test apartment. The results of the experiments indicated that humidity can

  18. 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

  19. Nozzle for discharging ventilation air from a ventilation system

    SciTech Connect

    Elfverson, S.E.

    1986-09-30

    This patent describes a nozzle for discharging ventilation air from a ventilation system, preferably arranged in a vehicle, including at least one outlet housing with a through-flow duct for ventilation air, a fixed plate transverse to the flow duct and rigidly attached to the outlet housing, and a plurality of plates parallel to the fixed plate. These plates are mutually displaceable in a direction transverse to the flow duct under the action of a control lever passing through the plates, the plates being formed with perforation patterns, which in coaction form ventilation ducts through which the ventilation air can flow and in response to the setting of the control lever cause deviation of the flow direction of the ventilation air. Each displaceable plate is formed with a grid cross comprising at least two intersecting bars, of which one bar has a substantially circular cross section, while the other bar has a substantially elliptical cross section and wherein the control lever is adapted to grip round a grid cross, the control lever having two pairs of longitudinal slots. One pair of the slots is adapted to grip without play one of the intersecting bars in each respective grid cross. The other pair of slots comprises a first slot adapted to grip without play the other of the intersecting bars, and a second slot formed with a width disabling engagement with the other of the intersecting bars.

  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. JAMA Patient Page: Mechanical Ventilation

    MedlinePLUS

    ... ventilators , is used routinely when persons have general anesthesia (unconsciousness) for operations, for critically ill individuals who ... sedative medications, or, in the case of general anesthesia, after medications are given to produce unconsciousness to ...

  2. Literature Review of Displacement Ventilation

    E-print Network

    Cho, S.; Im, P.; Haberl, J. S.

    Performance Evaluation and Design Guidelines for Displacement Ventilation” by Chen and Clicksman (2003), were used to begin the literature search. Their references include papers, articles, and web sites presenting major contributions to the understanding...

  3. 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.

  4. Pressure control model for transport of liquid mercury in carbon nanotubes

    Microsoft Academic Search

    H. W. Zhang; Z. Q. Zhang; L. Wang; Y. G. Zheng; J. B. Wang; Z. K. Wang

    2007-01-01

    Carbon nanotubes have a significant application in nanotechnology as nanopipes conveying fluids. In this letter, a pressure control model for transport of liquid mercury through carbon nanotubes using classical molecular dynamics simulations in conjunction with an atomistic model is presented. Wetting of single-walled carbon nanotubes by mercury occurs above a threshold pressure of liquid mercury. The liquid mercury can be

  5. Pressure control of a Moscow water supply system using expert system technology

    Microsoft Academic Search

    B. Coulbeck; B. Ulanicki; J. P. Rance; V. V. Deviatkov; S. Kosov; I. Glukhovsky

    1996-01-01

    The paper presents modeling and simulation studies of the current, semi-manual, and the proposed fully automatic pressure control schemes for the Zelenograd water supply system. Dynamic operational simulations are an essential feature of the project. However, it was necessary to enhance the network hydraulic simulator by including pressure feedback controls in order to produce acceptable results. Analysis of the operational

  6. Progress in Blood Pressure Control in Autosomal Dominant Polycystic Kidney Disease

    Microsoft Academic Search

    Tevfik Ecder; Charles L. Edelstein; Godela M. Fick-Brosnahan; Ann M. Johnson; Irene T. Duley; Patricia A. Gabow; Robert W. Schrier

    2000-01-01

    Hypertension occurs commonly in autosomal dominant polycystic kidney disease (ADPKD) and is an important factor in the progression of the disease and cardiovascular mortality. The aim of this prospective 15-year study is to report the rate of blood pressure control and the potential effect of a 10-point education program developed by our center for ADPKD patients and their physicians. The

  7. Dynamic Redesign of a Flow Control Servovalve Using a Pressure Control Pilot

    E-print Network

    Perry Y. Li

    2001-01-01

    In this paper, the dynamic performance of an unconventional two-spool flow control servo valve using a pressure control pilot is analyzed. Such valves are less expensive than typical servovalves but also tend to be limited in their dynamic performance. Based on a previously developed eight state

  8. Pressure-controlled motion of single polymers through solid-state nanopores

    E-print Network

    1 Pressure-controlled motion of single polymers through solid-state nanopores Bo Lu1 , David P of a pressure gradient across the nanopore yields a second molecular driving force that provides new freedom for studying molecules in nanopores. In this work, we show that opposing pressure and voltage bias enables

  9. 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.

  10. 21 CFR 868.5955 - Intermittent mandatory ventilation attachment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... false Intermittent mandatory ventilation attachment. 868.5955 Section...5955 Intermittent mandatory ventilation attachment. (a) Identification. An intermittent mandatory ventilation (IMV) attachment is a...

  11. 21 CFR 868.5955 - Intermittent mandatory ventilation attachment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... false Intermittent mandatory ventilation attachment. 868.5955 Section...5955 Intermittent mandatory ventilation attachment. (a) Identification. An intermittent mandatory ventilation (IMV) attachment is a...

  12. 21 CFR 868.5955 - Intermittent mandatory ventilation attachment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... false Intermittent mandatory ventilation attachment. 868.5955 Section...5955 Intermittent mandatory ventilation attachment. (a) Identification. An intermittent mandatory ventilation (IMV) attachment is a...

  13. 21 CFR 868.5955 - Intermittent mandatory ventilation attachment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... false Intermittent mandatory ventilation attachment. 868.5955 Section...5955 Intermittent mandatory ventilation attachment. (a) Identification. An intermittent mandatory ventilation (IMV) attachment is a...

  14. 21 CFR 868.5955 - Intermittent mandatory ventilation attachment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... false Intermittent mandatory ventilation attachment. 868.5955 Section...5955 Intermittent mandatory ventilation attachment. (a) Identification. An intermittent mandatory ventilation (IMV) attachment is a...

  15. Advanced Controls and Sustainable Systems for Residential Ventilation

    E-print Network

    1 Advanced Controls and Sustainable Systems for Residential Ventilation William J.N. Turner & Iain..................................................................................................................... 8 Residential Ventilation Standards..........................................................................................9 Passive and Hybrid Ventilation

  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 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 54 - 57 months. No additional O-ring failures have been observed since the last interim report was issued. Aging and periodic leak testing will continue for the remaining PCV fixtures. Additional irradiation of several fixtures is recommended to maintain a balance between thermal and radiation exposures similar to that experienced in storage, and to show the degree of consistency of radiation response between GLT and GLT-S O-rings.

  17. [Ventilation in special situations. Mechanical ventilation in status asthmaticus].

    PubMed

    Molini Menchón, N; Ibiza Palacios, E; Modesto i Alapont, V

    2003-10-01

    The indications for mechanical ventilation in status asthmaticus are cardiopulmonary arrest, significant alteration of consciousness, respiratory exhaustion, and progressive respiratory insufficiency despite aggressive bronchodilator treatment. In mechanical ventilation for status asthmaticus, a specific strategy directed at reducing dynamic hyperinflation must be used, with low tidal volumes and long expiratory times, achieved by diminishing respiratory frequency. This ventilatory pattern produces permissive hypercapnia, which is generally well tolerated with suitable sedation. The best methods for detecting and/or controlling dynamic hyperinflation in ventilated patients with status asthmaticus are the flow/time and flow/volume respiratory curves, pulmonary volume at the end of inspiration, and the pressure plateau. In addition to mechanical ventilation the child must receive sedation with or without a muscle relaxant to prevent barotrauma and accidental extubation. Bronchodilator treatment with beta-adrenergic agonists, methyl-prednisolone, and intravenous aminophylline are also required. A combination of inhaled salbutamol and nebulized ipratropium in the inspiratory branch of the ventilator should be used in patients in whom this treatment is effective. Currently there is insufficient evidence on the efficiency of other treatments in status asthmaticus and these should be used as rescue treatments. PMID:14519306

  18. 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).

  19. 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. PMID:24183921

  20. Detection of porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) antibodies in meat juice samples from Polish wild boar (Sus scrofa L.).

    PubMed

    Fabisiak, Micha?; Podgórska, Katarzyna; Skrzypiec, Ewelina; Szczotka, Anna; Stadejek, Tomasz

    2013-12-01

    PCV2 and PRRSV are two important pathogens of domestic swine. There is considerable evidence that the infection is also present in wild boars. Meat juice provides an alternative to serum for antibody testing, and it has been used in testing for many important porcine infectious diseases. Samples of brachial muscle were collected from 142 wild boars shot in different regions of Poland during the 2006/2007 and 2007/2008 hunting seasons. Meat juice harvested from muscle samples was tested using an ELISA test specific for PCV2 and PRRSV antibodies. Additionally, IgG and IgM antibodies specific for PCV2 were detected in order to estimate the status of the PCV2 infection. Only one of the tested meat juice samples was positive for PRRSV (0.7%), and 68 out of 142 (47.9%) samples were positive for PCV2. Of the positive animals, 4 (2.8%) had an antibody profile suggesting active infection, 2 (1.4%) early active infection, and 62 (43.7%) late infection. Also, a lack of association between the age of the animals and the presence of antibodies related to the infection was noticed. PMID:23974935

  1. 30 CFR 57.8532 - Opening and closing ventilation doors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Opening and closing ventilation doors. 57.8532 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8532 Opening and closing ventilation doors. When ventilation...

  2. 30 CFR 57.8532 - Opening and closing ventilation doors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Opening and closing ventilation doors. 57.8532 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8532 Opening and closing ventilation doors. When ventilation...

  3. 30 CFR 57.8532 - Opening and closing ventilation doors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Opening and closing ventilation doors. 57.8532 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8532 Opening and closing ventilation doors. When ventilation...

  4. 30 CFR 57.8532 - Opening and closing ventilation doors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Opening and closing ventilation doors. 57.8532 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8532 Opening and closing ventilation doors. When ventilation...

  5. 30 CFR 57.8532 - Opening and closing ventilation doors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Opening and closing ventilation doors. 57.8532 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8532 Opening and closing ventilation doors. When ventilation...

  6. Energy Impact of Residential Ventilation Standards in California

    E-print Network

    ...................................................................................................................................... 6 Non-compliant systems .............................................................................................................................. 7 Source Control Ventilation...................................................................................................

  7. Effect of intensive blood pressure control on the course of type 1 diabetic nephropathy

    Microsoft Academic Search

    Julia Breyer Lewis; Tomas Berl; Raymond P. Bain; Richard D. Rohde; Edmund J. Lewis

    1999-01-01

    Diabetic nephropathy is the most common cause of end-stage renal disease in the United States. We undertook a study to assess the impact of assignment to different levels of blood pressure control on the course of type 1 diabetic nephropathy in patients receiving angiotensin-converting enzyme (ACE) inhibitor therapy. We also examined the long-term course of this well-characterized cohort of patients

  8. Dynamic Analysis of a Two-Stage Two-Spool Pressure Control Servovalve

    Microsoft Academic Search

    S. T. Tsai; A. Akers; S. J. Lin

    1990-01-01

    Experimental results for a unique design of a two-spool pressure control valve were reported by Anderson (1984). The first stage is a dynamically stable flapper-nozzle valve for which a mathematical model is already available (Lin and Akers, 1989a). For the second stage, however, which consists of two parallel spools in a common body, no such model existed. The purpose of

  9. Growth of bulk GaN single crystals by the pressure-controlled solution growth method

    Microsoft Academic Search

    T. Inoue; Y Seki; O Oda; S Kurai; Y Yamada; T Taguchi

    2001-01-01

    Crystal growth of GaN by the pressure-controlled solution growth (PC-SG) method has been carried out using a high-pressure furnace. We have investigated the effect of the supersaturation of nitrogen atoms (the rate of increase of nitrogen pressure) in order to grow large GaN single crystals. It was found that the rate of increase of nitrogen pressure affected the size of

  10. A ROBUST INTELLIGENT PID-TYPE FUZZY CONTROL STRUCTURE FOR PRESSURE CONTROL

    Microsoft Academic Search

    N. Kanagaraj; R. Kumar; P. Sivashanmugam

    2008-01-01

    A PID-type fuzzy controller for regulating pressure in a pilot pressure control system has been demonstrated in this article. The control algorithm for the proposed control logic has been developed in embedded Keil environment, and then downloaded into a target ARM7 microcontroller (AT91M55800A) for real-time validation. Although well-tuned conventional fuzzy controllers perform well around normal working regions, their outputs have

  11. 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%; ?(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%; ?(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. PMID:25492834

  12. Energy Recovery Ventilator Membrane Efficiency Testing

    E-print Network

    Rees, Jennifer Anne

    2013-05-07

    A test setup was designed and built to test energy recovery ventilator membranes. The purpose of this test setup was to measure the heat transfer and water vapor transfer rates through energy recover ventilator membranes and find their effectiveness...

  13. Fracture ventilation by surface winds

    NASA Astrophysics Data System (ADS)

    Nachshon, U.; Dragila, M. I.; Weisbrod, N.

    2011-12-01

    Gas exchange between the Earth subsurface and the atmosphere is an important mechanism, affecting hydrological, agricultural and environmental processes. From a hydrological aspect, water vapor transport is the most important process related to Earth-atmosphere gas exchange. In respect to agriculture, gas transport in the upper soil profile is important for soil aeration. From an environmental aspect, emission of volatile radionuclides, such as 3H, 14C and Rd from radioactive waste disposal facilities; volatile organic components from industrial sources and Rn from natural sources, all found in the upper vadose zone, can greatly affect public health when emissions occur in populated areas. Thus, it is vital to better understand gas exchange processes between the Earth's upper crust and atmosphere. Four major mechanisms are known to transfer gases between ground surface and atmosphere: (1) Diffusion; (2) Pressure gradients between ground pores and atmosphere due to changes in barometric pressure; (3) Density-driven gas flow in respond to thermal gradients in the ground; and (4) Winds above the ground surface. Herein, the wind ventilation mechanism is studied. Whereas the wind's impact on ground ventilation was explored in several studies, the physical mechanisms governing this process were hardly quantified or characterized. In this work the physical properties of fracture ventilation due to wind blowing along land surface were explored and quantified. Both field measurements and Hele-Shaw experiments under controlled conditions in the laboratory were used to study this process. It was found that winds in the range of 0.3 m/s result in fracture ventilation down to a depth of 0.2 m. As wind velocity increases, the depth of the ventilation inside the fracture increases respectively, in a linear manner. In addition, the fracture aperture also affects the depth of ventilation, which grows as fracture aperture increases. For the maximal examined aperture of 2 cm and wind velocity of 1.25 m/s, fracture ventilation was deeper than 0.45 m. This study sheds new light on fracture ventilation, showing that moderate winds may increase evaporation and gas exchange between fractured media and the atmosphere. Even though wind impact is limited to the top 0.5 m below the ground surface, it is an important process as most of the biological activities, as well as important hydrological processes occur in this region. Wind effect should be considered when modeling mass and energy balances between the Earth upper crust and atmosphere.

  14. Flow transport and gas mixing during invasive high frequency oscillatory ventilation.

    PubMed

    Alzahrany, Mohammed; Banerjee, Arindam; Salzman, Gary

    2014-06-01

    A large Eddy simulation (LES) based computational fluid dynamics study was performed to investigate gas transport and mixing in patient specific human lung models during high frequency oscillatory ventilation. Different pressure-controlled waveforms (sinusoidal, exponential and square) and ventilator frequencies (15, 10 and 6Hz) were used (tidal volume=50mL). The waveforms were created by solving the equation of motion subjected to constant lung wall compliance and flow resistance. Simulations were conducted with and without endotracheal tube to understand the effect of invasive management device. Variation of pressure-controlled waveform and frequency exhibits significant differences on counter flow pattern, which could lead to a significant impact on the gas mixing efficiency. Pendelluft-like flow was present for the sinusoidal waveform at all frequencies but occurred only at early inspiration for the square waveform at highest frequency. The square waveform was most efficient for gas mixing, resulting in the least wall shear stress on the lung epithelium layer thereby reducing the risk of barotrauma to both airways and the alveoli for patients undergoing therapy. PMID:24656889

  15. Ventilation-Synchronous Magnetic Resonance Microscopy of Pulmonary Structure and Ventilation in

    E-print Network

    Ventilation-Synchronous Magnetic Resonance Microscopy of Pulmonary Structure and Ventilation helium (3 He) gas to acquire images that dem- onstrate pulmonary vasculature and ventilated airways of these structures relative to the less vascular surrounding tissues. A constant- flow ventilator was developed

  16. We compared the efficacy of positive pressure ventilation (PPV) vs negative pressure ventilation (NPV) in providing

    E-print Network

    Shadmehr, Reza

    We compared the efficacy of positive pressure ventilation (PPV) vs negative pressure ventilationEMG), minute ventilation (VE),tidal volume (VT), and end-tidal CO (etCOÃ? during 15 minutes of PPV and NPV. For each subject, ventilator adjustments were made to obtain VE similar to levels measured during quiet

  17. 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.

  18. STATE OF CALIFORNIA MECHANICAL VENTILATION AND REHEAT

    E-print Network

    STATE OF CALIFORNIA MECHANICAL VENTILATION AND REHEAT CEC-MECH-3C (Revised 08/09) CALIFORNIA ENERGY COMMISSION MECHANICAL VENTILATION AND REHEAT MECH-3C PROJECT NAME DATE MECHANICAL VENTILATION §121(b)2 REHEAT'D V.A. Max of D or G Design Ventilation Air cfm 50% of Design Zone Supply cfm B x 0.4 cfm/ft² Max

  19. Equipment needs for noninvasive mechanical ventilation

    Microsoft Academic Search

    B. Schonhofer; S. Sortor-Leger

    2002-01-01

    ABSTRACT: Noninvasive mechanical,ventilation (NIV) has a long tradition for the treatment of chronic respiratory failure and more recently has also been applied in acute respiratory failure. Based on this experience both critical care ventilators and portable ventilators are used to perform,NIV. The individual choice of ventilator type should depend on the patient9s condition and also on the expertise of attending

  20. 46 CFR 72.05-50 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Ventilation. 72.05-50 Section 72.05-50...Structural Fire Protection § 72.05-50 Ventilation. (a) Where the term duct is...trunks, plenums, and any other type of ventilation piping, chambers, or...

  1. 46 CFR 168.15-50 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Ventilation. 168.15-50 Section 168.15-50... Accommodations § 168.15-50 Ventilation. (a) All quarters must be adequately...the vessel. (b) When mechanical ventilation is provided for sleeping rooms,...

  2. Procedures and Standards for Residential Ventilation System

    E-print Network

    1 Procedures and Standards for Residential Ventilation System Commissioning: An Annotated and by the California Energy Commission under Pier Contract 500-08-061. Key terms: residential, ventilation.C. and C.P. Wray. 2013. Procedures and Standards for Residential Ventilation System Commissioning

  3. 46 CFR 72.05-50 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation. 72.05-50 Section 72.05-50...Structural Fire Protection § 72.05-50 Ventilation. (a) Where the term duct is...trunks, plenums, and any other type of ventilation piping, chambers, or...

  4. 46 CFR 98.25-75 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation. 98.25-75 Section 98.25-75...Anhydrous Ammonia in Bulk § 98.25-75 Ventilation. (a) All enclosed spaces containing...connections shall be provided with mechanical ventilation of sufficient capacity to...

  5. 46 CFR 194.15-5 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation. 194.15-5 Section 194.15-5...Scientific Laboratory § 194.15-5 Ventilation. (a) Operations, reactions...equipped with an independent power exhaust ventilation system which terminates so as to...

  6. 14 CFR 23.831 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Ventilation. 23.831 Section 23.831 Aeronautics...Cargo Accommodations § 23.831 Ventilation. Link to an amendment published...set forth as follows: § 23.831 Ventilation. (c) For jet pressurized...

  7. 46 CFR 72.05-50 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation. 72.05-50 Section 72.05-50...Structural Fire Protection § 72.05-50 Ventilation. (a) Where the term duct is...trunks, plenums, and any other type of ventilation piping, chambers, or...

  8. Reduceret energiforbrug til ventilation af bygninger

    E-print Network

    Reduceret energiforbrug til ventilation af bygninger hvori der systematisk er valgt lav. 23. November 2007 #12;#12;Reduced energy use for ventilation of buildings through selection of low ventilation rate on perceived quality of air polluted by different materials, small ­ scale and full ­ scale

  9. 9 CFR 91.21 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Ventilation. 91.21 Section 91.21 Animals...Vessels and Accommodations § 91.21 Ventilation. Each underdeck compartment on...equipped with a system of mechanical ventilation that will furnish a complete...

  10. 46 CFR 72.05-50 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation. 72.05-50 Section 72.05-50...Structural Fire Protection § 72.05-50 Ventilation. (a) Where the term duct is...trunks, plenums, and any other type of ventilation piping, chambers, or...

  11. 46 CFR 72.05-50 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation. 72.05-50 Section 72.05-50...Structural Fire Protection § 72.05-50 Ventilation. (a) Where the term duct is...trunks, plenums, and any other type of ventilation piping, chambers, or...

  12. 46 CFR 98.25-75 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation. 98.25-75 Section 98.25-75...Anhydrous Ammonia in Bulk § 98.25-75 Ventilation. (a) All enclosed spaces containing...connections shall be provided with mechanical ventilation of sufficient capacity to...

  13. 46 CFR 194.15-5 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Ventilation. 194.15-5 Section 194.15-5...Scientific Laboratory § 194.15-5 Ventilation. (a) Operations, reactions...equipped with an independent power exhaust ventilation system which terminates so as to...

  14. 9 CFR 91.21 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Ventilation. 91.21 Section 91.21 Animals...Vessels and Accommodations § 91.21 Ventilation. Each underdeck compartment on...equipped with a system of mechanical ventilation that will furnish a complete...

  15. 9 CFR 91.21 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Ventilation. 91.21 Section 91.21 Animals...Vessels and Accommodations § 91.21 Ventilation. Each underdeck compartment on...equipped with a system of mechanical ventilation that will furnish a complete...

  16. The fluid mechanics of natural ventilation

    Microsoft Academic Search

    Paul Linden

    1999-01-01

    Natural ventilation of buildings is the flow generated by temperature differences and by the wind. Modern buildings have extreme designs with large, tall open plan spaces and large cooling requirements. Natural ventilation offers a means of cooling these buildings and providing good indoor air quality. The essential feature of ventilation is an exchange between an interior space and the external

  17. 46 CFR 194.15-5 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation. 194.15-5 Section 194.15-5...Scientific Laboratory § 194.15-5 Ventilation. (a) Operations, reactions...equipped with an independent power exhaust ventilation system which terminates so as to...

  18. 46 CFR 98.25-75 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Ventilation. 98.25-75 Section 98.25-75...Anhydrous Ammonia in Bulk § 98.25-75 Ventilation. (a) All enclosed spaces containing...connections shall be provided with mechanical ventilation of sufficient capacity to...

  19. 46 CFR 194.15-5 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation. 194.15-5 Section 194.15-5...Scientific Laboratory § 194.15-5 Ventilation. (a) Operations, reactions...equipped with an independent power exhaust ventilation system which terminates so as to...

  20. 46 CFR 98.25-75 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation. 98.25-75 Section 98.25-75...Anhydrous Ammonia in Bulk § 98.25-75 Ventilation. (a) All enclosed spaces containing...connections shall be provided with mechanical ventilation of sufficient capacity to...

  1. 9 CFR 91.21 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Ventilation. 91.21 Section 91.21 Animals...Vessels and Accommodations § 91.21 Ventilation. Each underdeck compartment on...equipped with a system of mechanical ventilation that will furnish a complete...

  2. 9 CFR 91.21 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Ventilation. 91.21 Section 91.21 Animals...Vessels and Accommodations § 91.21 Ventilation. Each underdeck compartment on...equipped with a system of mechanical ventilation that will furnish a complete...

  3. 46 CFR 168.15-50 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation. 168.15-50 Section 168.15-50... Accommodations § 168.15-50 Ventilation. (a) All quarters must be adequately...the vessel. (b) When mechanical ventilation is provided for sleeping rooms,...

  4. Humidity Implications for Meeting Residential Ventilation Requirements

    E-print Network

    1 LBNL-62182 Humidity Implications for Meeting Residential Ventilation Requirements Iain S. Walker for Meeting Residential Ventilation Requirements ABSTRACT In 2003 ASHRAE approved the nation's first residential ventilation standard, ASHRAE Standard 62.2. Because meeting this standard can significantly change

  5. May 1999 LBNL -42975 ASHRAE'S RESIDENTIAL VENTILATION

    E-print Network

    May 1999 LBNL - 42975 ASHRAE'S RESIDENTIAL VENTILATION STANDARD: EXEGESIS OF PROPOSED STANDARD 62 Committee on "Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings", SPC 62.2P, approved ASHRAE's first complete standard on residential ventilation for public review

  6. 46 CFR 194.15-5 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation. 194.15-5 Section 194.15-5...Scientific Laboratory § 194.15-5 Ventilation. (a) Operations, reactions...equipped with an independent power exhaust ventilation system which terminates so as to...

  7. 46 CFR 168.15-50 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation. 168.15-50 Section 168.15-50... Accommodations § 168.15-50 Ventilation. (a) All quarters must be adequately...the vessel. (b) When mechanical ventilation is provided for sleeping rooms,...

  8. 46 CFR 168.15-50 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation. 168.15-50 Section 168.15-50... Accommodations § 168.15-50 Ventilation. (a) All quarters must be adequately...the vessel. (b) When mechanical ventilation is provided for sleeping rooms,...

  9. 46 CFR 98.25-75 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation. 98.25-75 Section 98.25-75...Anhydrous Ammonia in Bulk § 98.25-75 Ventilation. (a) All enclosed spaces containing...connections shall be provided with mechanical ventilation of sufficient capacity to...

  10. Formaldehyde Transfer in Residential Energy Recovery Ventilators

    E-print Network

    Formaldehyde Transfer in Residential Energy Recovery Ventilators Erin L. Hult, Henry Willem and Max and Sherman MH, 2014, Formaldehyde transfer in residential energy recovery ventilators, Building design used in many energy recovery ventilators (ERVs) is designed to transfer heat and moisture between

  11. 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.

  12. Ventilator for internal combustion engine

    Microsoft Academic Search

    Aoki

    1986-01-01

    A ventilator is described for an internal combustion engine, consisting of: a housing; a diaphragm that divides the inside of the housing into a pressure chamber communicating with a crankcase and an atmospheric chamber communicating with the atmosphere; an outlet tube extending vertically in the pressure chamber and communicating with an intake manifold; a valve fixed to the diaphragm and

  13. Night ventilation control strategies in office buildings

    SciTech Connect

    Wang, Zhaojun; Yi, Lingli; Gao, Fusheng [School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090 (China)

    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)

  14. 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 ?2 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

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

    SciTech Connect

    Daugherty, W.

    2012-08-30

    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 54-72 months, which is still bounding to O-ring temperatures during storage in K-Area Complex (KAC). Based on expectations that the fixtures aging at 200 ºF will remain leak-tight 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 30 - 36 months. For O-ring fixtures that have failed the room temperature leak test and been disassembled, the O-rings displayed a compression set ranging from 51 – 96%. This is greater than seen to date for any packages inspected during KAC field 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.

  16. ALTERNATIVE PROCESSING TECHNOLOGIES TO REDUCE TRANS ACID CONTENTS OF FOOD OILS: INTERESTERIFICATION, PLANT BREEDING, AND PRESSURE CONTROLLED HYDROGENATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alternative processing strategies to reduce trans acid contents of food oils include interesterification, genetic and plant breeding for triglyceride and fatty acid composition and pressure controlled hydrogenation. This paper will review research in these areas. Random interesterification of liqu...

  17. 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 more complex and case specific. They are subject to occupational safety legislation and not discussed here.

  18. Speed and pressure control system design and simulation for a compression press

    SciTech Connect

    Floersch, R.H.

    1981-04-01

    A new system design using closed loop control on the hydraulic system on compression transfer presses used to make filled elastomer parts will improve accuracy and repeatability of speed and pressure control during critical pre-cure forming stages. The present open loop system does not provide the control necessary to mold repeatably the filled elastomer products. These products form with great difficulty because of high loading levels of filler materials. The new system will mean improved wall thickness control of loaded elastomer parts, thus reducing the amount of scrap caused by wall thickness variations.

  19. Blood Pressure Control in Hispanics in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial

    Microsoft Academic Search

    Karen L. Margolis; Linda B. Piller; Charles E. Ford; Mario A. Henriquez; William C. Cushman; Paula T. Einhorn; Pedro J. Colon; Donald G. Vidt; Nathan D. Wong; Jackson T. Wright; David C. Goff

    2009-01-01

    Historically, blood pressure control in Hispanics has been considerably less than that of non-Hispanic whites and blacks. We compared determinants of blood pressure control among Hispanic white, Hispanic black, non-Hispanic white, and non-Hispanic black participants (N32 642) during follow-up in a randomized, practice-based, active- controlled trial. Hispanic blacks and whites represented 3% and 16% of the cohort, respectively; 33% were

  20. 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.

  1. [Economic impact of Circovac® - vaccination in a PCV2 subclinically infected farm in Switzerland on performance parameters].

    PubMed

    Sidler, X; Kurmann, J; Brugnera, E; Sydler, T

    2012-10-01

    Vaccination of dams in a PCV2 subclinically infected farm 2 and 4 weeks before insemination, with a booster at 12 weeks of gestation did not influence fertility parameters of the dams. However, growth parameters of offspring of vaccinated sows improved significantly (+ 51 g/d), resulting in a shorter growing period of 9 days and a massively improved economy. Mortality of weaners and fattening pigs was not significantly influenced by dam vaccination. Nevertheless, compared to a period of 6 months before vaccination, the mortality rate declined in the weaning period by 0,3 % and in the fattening period by 5,5 %. The Return on Investment (ROI) was calculated with 1:9.5. Even, the historically low pork prices in 2011 led to a ROI of 1:7. PMID:23027512

  2. Phylogenetic comparison of porcine circovirus type 2 (PCV2) and porcine reproductive respiratory syndrome virus (PRRSV) strains detected in domestic pigs until 2008 and in 2012 in Croatia

    PubMed Central

    2014-01-01

    Background Porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) have been present for the last 2 decades in Croatia, causing large economical losses in the pig production. The clinical features of the infections are mostly manifested by the development of respiratory problems, weight loss and poor growth performance, as well as reproductive failure in pregnant sows. Even though the infections are continuously recognized in some regions in Croatia, the heterogeneity of the detected viral strains from 2012 has not yet been investigated. The objective of this study was to compare virus strains of PCV2 and PRRSV detected until 2008 in Croatia with strains isolated in 2012 to gain a better epidemiological understanding of these two infections. Results PCV2 and PRRSV strains detected in 2012 in fattening pigs from regions where these two diseases have been previously described were compared to strains that have been detected in the same regions within the past two decades. The phylogenetic analysis revealed that the circulating PCV2 and PRRSV strains are distantly related to the previously described Croatian viral strains. However, when compared to known isolates from the GenBank a high genetic identity of PRRSV isolates with isolates from Hungary, Denmark and the Netherlands was found. Conclusion The results of this study reveal that even though PCV2 and PRRSV are constantly present in the investigated regions in Croatia, the viral strains found in 2012 genetically differ from those detected in earlier years. This indicates that new entries into the pig population appeared with regard to both infections, probably as a result of pig trade. PMID:24839544

  3. Immunogenicity and serotype-specific efficacy of a 9-valent pneumococcal conjugate vaccine (PCV-9) determined during an efficacy trial in The Gambia.

    PubMed

    Saaka, M; Okoko, B J; Kohberger, R C; Jaffar, S; Enwere, G; Biney, E E; Oluwalana, C; Vaughan, A; Zaman, S M A; Asthon, L; Goldblatt, D; Greenwood, B M; Cutts, F T; Adegbola, R A

    2008-07-01

    This study aimed to determine the immunogenicity of a 9-valent pneumococcal conjugate vaccine (PCV-9) in a subgroup of Gambian children enrolled in a large vaccine efficacy trial. To place the antibody results in context, in this paper we also report previously unpublished data on serotype-specific clinical vaccine efficacy from the main trial. In the sub-study, a single 2-4 ml venous blood specimen was collected from 212 Gambian children 4-6 weeks after the administration of a third dose of PCV-9 or placebo. IgG antibodies to pneumococcal serotype 1, 4, 5, 6B, 9V, 14, 18C, 19F and 23F polysaccharides were measured by ELISA. The proportions of infants with antibody concentrations above 0.2, 0.35 and 1.0 microg/ml, and the geometric mean concentrations (GMCs) of anti-pneumococcal polysaccharide antibodies were substantially higher for each serotype in children who received three doses of PCV-9 than those in the placebo group. Among PCV-9 recipients, GMCs ranged between 2.61 and 11.09 microg/ml with the highest being against serotype 14 and the lowest against 9V polysaccharide. The estimated overall protective antibody level for all nine serotypes, based on the vaccine efficacy against vaccine-type invasive pneumococcal disease (IPD) of 77% (95% CI: 51, 90) observed in the trial, was 2.3 microg/ml (95% CI: 1.0, 5.0). The PCV-9 studied was immunogenic in a Gambian population where it was also found to be efficacious. PMID:18514974

  4. Influence of long-term vaccination of a breeding herd of pigs against PCV2 on reproductive parameters.

    PubMed

    Pejsak, Z; Kusior, G; Pomorska-Mól, M; Podgórska, K

    2012-01-01

    The objective of the study was to evaluate an efficacy of sows vaccination protocols in the herd with serious problems affecting efficacy of reproduction. The study was performed in a large pig herd with about 1200 sows. Before vaccination against PCV2, farrowing rate in this farm was about 65%. Sows, boar and replacement gilts were immunized using Circovac vaccine (Merial, France) according to producer's recommendations. Parameters of production were analyzed since 2007 until 2010 in selected batches of sows inseminated at the same weeks of the year (17th, 18th, 19th and 20th) to eliminate seasonal variability. In total, 940 sows were subjected to the study. No significant changes in management during these years were introduced. The applied protocol of sow herd long-term vaccination proved to be very efficient. All measured production parameters: reproduction rate, number of piglets born alive, birth weight of piglets and number of piglets weaned per a litter improved after implementation of immunization program. Moreover, further improvement was observed with vaccination in the following reproduction cycles. The most spectacular effect of vaccination regarded average farrowing rate that increased from 64.76% in control group to 86.93% after basic vaccination. Two years after implementation of vaccination program this parameter reached 93.6%. Number of piglets weaned per sow per a litter improved from 10.31 to 11.74 after one year of vaccination and remained relatively stable through the following year. Simultaneously, the percentage of newborn piglets with birth weight < 1 kg decreased significantly (p < 0.05). To summarize, vaccination against PCV2 influenced positively the insemination rate, number of piglets born alive and weaned per litter as well as birth body weight and percentage of piglets weighing < 1 kg. PMID:22708355

  5. Particle deposition in ventilation ducts

    SciTech Connect

    Sippola, Mark R.

    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 {micro}m 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 experimental measurements was applied to evaluate particle losses in supply and return duct runs. Model results suggest that duct losses are negligible for particle sizes less than 1 {micro}m and complete for particle sizes greater than 50 {micro}m. Deposition to insulated ducts, horizontal duct floors and bends are predicted to control losses in duct systems. When combined with models for HVAC filtration and deposition to indoor surfaces to predict the ultimate fates of particles within buildings, these results suggest that ventilation ducts play only a small role in determining indoor particle concentrations, especially when HVAC filtration is present. However, the measured and modeled particle deposition rates are expected to be important for ventilation system contamination.

  6. CONFIDENTIAL: DO NOT QUOTE 1 Equivalence in Ventilation and

    E-print Network

    CONFIDENTIAL: DO NOT QUOTE 1 Equivalence in Ventilation and Indoor Air Quality M. H. Sherman, I ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation

  7. Architectural design of an advanced naturally ventilated building form

    Microsoft Academic Search

    Kevin J. Lomas

    2007-01-01

    Advanced stack-ventilated buildings have the potential to consume much less energy for space conditioning than typical mechanically ventilated or air-conditioned buildings. This paper describes how environmental design considerations in general, and ventilation considerations in particular, shape the architecture of advanced naturally ventilated (ANV) buildings. The attributes of simple and advanced naturally ventilated buildings are described and a taxonomy of ANV

  8. Ventilation Requirements in Hot Humid Climates

    E-print Network

    Walker, I. S.; Sherman, M. H.

    2006-01-01

    VENTILATION REQUIREMENTS IN HOT, HUMID CLIMATES I.S. Walker M. H. Sherman Staff Scientist Senior Scientist Lawrence Berkeley National Laboratory Berkeley CA ABSTRACT In 2003 ASHRAE approved the nation’s first residential... ventilation standard, ASHRAE Standard 62.2. Meeting this standard in new construction requires the use of mechanical ventilation, which in turn can often significantly increase the latent load faced in new homes. As the thermal performance of houses...

  9. Efficacy of stepwise sodium profile versus individualized dialysate sodium in blood pressure control among hemodialysis patients

    PubMed Central

    Shahgholian, Nahid; Hashemi, Maryam Sadat; Shahidi, Shahrzade

    2015-01-01

    Background: Hypertension is very common in patients with end-stage renal disease and accelerates cardiovascular morbidity and mortality. The most important factor in achieving normal blood pressure in these patients is reaching dry weight. Sodium and extracellular fluid balance play a vital role in this regard. Considering the lack of consensus about the efficacy of stepwise sodium profile and individualized dialysate sodium, this study aimed to determine the superior method for blood pressure control in hemodialysis patients. Materials and Methods: In a quasi-experimental study, patients satisfying the inclusion criteria were enrolled through convenience sampling. The patients were randomly assigned to two groups of stepwise sodium profile and individualized dialysate sodium. Information record form was used for data collection. Data were analyzed with paired and independent t-test and descriptive statistics using SPSS for Windows 20.0. Results: Patients in the two groups were similar in qualitative and quantitative background variables. While systolic blood pressure significantly decreased following hemodialysis with individualized dialysate sodium (P < 0.001), there was no significant difference between pre- and post-dialysis systolic blood pressure values using stepwise sodium profile (P = 0.060). Individualized dialysate sodium caused greater change in the mean systolic blood pressure than stepwise sodium profile did (P = 0.040). Pre- and post-dialysis diastolic blood pressure values showed significant differences in both groups (P < 0.001 using individualized dialysate sodium and P = 0.009 using stepwise sodium profile). However, the mean changes in diastolic blood pressure of the two groups were not significantly different (P = 0.295). Conclusions: We found no significant difference in interdialytic weight gain and blood pressure control by the two methods. The change in systolic blood pressure was lower in the stepwise profile method than in the individualized dialysate sodium method, and this method did not cause interdialytic hypertension. So, by adjusting the dialysis solution with regard to plasma sodium levels, lead to more blood pressure control. Meanwhile, the two groups were not significantly different in the mean changes of diastolic blood pressure. PMID:25709685

  10. High-frequency ventilation and conventional mechanical ventilation in newborn babies with respiratory distress syndrome: A prospective, randomized trial

    Microsoft Academic Search

    A. Pardou; D. Vermeylen; M. F. Muller; D. Detemmerman

    1993-01-01

    Objective. Morbidity and mortality remain high amongst babies ventilated for a respiratory distress syndrome (RDS). Whether newly developed ventilators allowing high frequency ventilation such as high frequen- cy flow interrupted ventilation (HFFIV) could decrease the morbidity and the mortality was investigated in a ran- domized study. Design: Preterm babies weighing < 1800 g suffering from RDS and ventilated by conventional

  11. 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.

  12. 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.

  13. 21 CFR 888.4230 - Cement ventilation tube.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device...

  14. 21 CFR 888.4230 - Cement ventilation tube.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device...

  15. 49 CFR 192.187 - Vaults: Sealing, venting, and ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...false Vaults: Sealing, venting, and ventilation. 192.187 Section 192.187 ...187 Vaults: Sealing, venting, and ventilation. Each underground vault or closed...millimeters) in diameter; (2) The ventilation must be enough to minimize the...

  16. 21 CFR 888.4230 - Cement ventilation tube.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device...

  17. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 2010-10-01 2010-10-01 false Ventilation for closed spaces. 92.15-10 Section...MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except...

  18. 49 CFR 192.187 - Vaults: Sealing, venting, and ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...false Vaults: Sealing, venting, and ventilation. 192.187 Section 192.187 ...187 Vaults: Sealing, venting, and ventilation. Each underground vault or closed...millimeters) in diameter; (2) The ventilation must be enough to minimize the...

  19. 46 CFR 127.260 - Ventilation for accommodations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation for accommodations. 127.260 ...Construction and Arrangements § 127.260 Ventilation for accommodations. (a) Each...tons must be provided with a mechanical ventilation system unless the cognizant OCMI...

  20. 24 CFR 3280.103 - Light and ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 false Light and ventilation. 3280.103 Section 3280.103...Considerations § 3280.103 Light and ventilation. (a) Lighting. Each habitable...whichever is greater. (b) Whole-house ventilation. Each manufactured home must be...

  1. 46 CFR 127.260 - Ventilation for accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation for accommodations. 127.260 ...Construction and Arrangements § 127.260 Ventilation for accommodations. (a) Each...tons must be provided with a mechanical ventilation system unless the cognizant OCMI...

  2. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Mechanical ventilation system: General. 154.1200 Section...and Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a) Each...

  3. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Mechanical ventilation system: Standards. 154.1205 Section...and Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each...

  4. 24 CFR 3280.103 - Light and ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 false Light and ventilation. 3280.103 Section 3280.103...Considerations § 3280.103 Light and ventilation. (a) Lighting. Each habitable...whichever is greater. (b) Whole-house ventilation. Each manufactured home must be...

  5. Commissioning Residential Ventilation Systems: A Combined Assessment of

    E-print Network

    Commissioning Residential Ventilation Systems: A Combined Assessment of Energy and Air Quality ventilation systems are being installed in new California homes. Few measurements are available of commissioning residential whole- house ventilation systems that are intended to comply

  6. 46 CFR 153.316 - Special cargo pumproom ventilation rate.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Special cargo pumproom ventilation rate. 153.316 Section 153.316...Design and Equipment Cargo Handling Space Ventilation § 153.316 Special cargo pumproom ventilation rate. When Table 1 refers to...

  7. 46 CFR 127.260 - Ventilation for accommodations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation for accommodations. 127.260 ...Construction and Arrangements § 127.260 Ventilation for accommodations. (a) Each...tons must be provided with a mechanical ventilation system unless the cognizant OCMI...

  8. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Ventilation and drainage. 27.1187 Section...Powerplant Fire Protection § 27.1187 Ventilation and drainage. Each compartment...installation must have provision for ventilation and drainage of flammable fluids....

  9. 46 CFR 153.316 - Special cargo pumproom ventilation rate.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Special cargo pumproom ventilation rate. 153.316 Section 153.316...Design and Equipment Cargo Handling Space Ventilation § 153.316 Special cargo pumproom ventilation rate. When Table 1 refers to...

  10. 49 CFR 192.187 - Vaults: Sealing, venting, and ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...false Vaults: Sealing, venting, and ventilation. 192.187 Section 192.187 ...187 Vaults: Sealing, venting, and ventilation. Each underground vault or closed...millimeters) in diameter; (2) The ventilation must be enough to minimize the...

  11. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Mechanical ventilation system: General. 154.1200 Section...and Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a) Each...

  12. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Ventilation and drainage. 27.1187 Section...Powerplant Fire Protection § 27.1187 Ventilation and drainage. Each compartment...installation must have provision for ventilation and drainage of flammable fluids....

  13. 46 CFR 153.316 - Special cargo pumproom ventilation rate.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Special cargo pumproom ventilation rate. 153.316 Section 153.316...Design and Equipment Cargo Handling Space Ventilation § 153.316 Special cargo pumproom ventilation rate. When Table 1 refers to...

  14. 33 CFR 183.630 - Standards for natural ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Standards for natural ventilation. 183.630 Section 183.630 Navigation...SAFETY BOATS AND ASSOCIATED EQUIPMENT Ventilation § 183.630 Standards for natural ventilation. (a) For the purpose of §...

  15. HVAC EFFICIENCY BUSINESS CASE DEMAND CONTROL KITCHEN VENTILATION

    E-print Network

    California at Davis, University of

    HVAC EFFICIENCY BUSINESS CASE DEMAND CONTROL KITCHEN VENTILATION Selecting, financing ventilation (DCKV) for kitchen exhaust hoods. Implementation can be relatively simple in either new of demand control kitchen ventilation (DCKV) in many small, medium, and large kitchen exhaust hood

  16. RESEARCH ARTICLE Open Access Noninvasive ventilation reduces energy

    E-print Network

    Paris-Sud XI, Université de

    RESEARCH ARTICLE Open Access Noninvasive ventilation reduces energy expenditure in amyotrophic with a shift of the burden of ventilation to extradiaphragmatic inspiratory muscles, including neck muscles prognostic value. We hypothesized that noninvasive ventilation (NIV) would relieve inspiratory neck muscles

  17. Evaluation of Existing Technologies for Meeting Residential Ventilation

    E-print Network

    LBNL-59998 Evaluation of Existing Technologies for Meeting Residential Ventilation Requirements Ventilation Requirements and Distribution System Research for 2008 Building Efficiency Standards Task 3.2 Evaluation of Existing Technologies for Meeting Residential Ventilation Requirements Prepared in Support

  18. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 2012-10-01 2012-10-01 false Ventilation for closed spaces. 92.15-10 Section...MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except...

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Mechanical ventilation system: Standards. 154.1205 Section...and Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each...

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

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Mechanical ventilation system: Standards. 154.1205 Section...and Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each...

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Mechanical ventilation system: General. 154.1200 Section...and Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a) Each...

  2. 21 CFR 888.4230 - Cement ventilation tube.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device...

  3. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 2011-10-01 2011-10-01 false Ventilation for closed spaces. 92.15-10 Section...MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except...

  4. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 2014-10-01 false Ventilation for closed spaces. 92.15-10 Section...MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except...

  5. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 2013-10-01 false Ventilation for closed spaces. 92.15-10 Section...MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except...

  6. 24 CFR 3280.103 - Light and ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 false Light and ventilation. 3280.103 Section 3280.103...Considerations § 3280.103 Light and ventilation. (a) Lighting. Each habitable...whichever is greater. (b) Whole-house ventilation. Each manufactured home must be...

  7. 49 CFR 192.187 - Vaults: Sealing, venting, and ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...false Vaults: Sealing, venting, and ventilation. 192.187 Section 192.187 ...187 Vaults: Sealing, venting, and ventilation. Each underground vault or closed...millimeters) in diameter; (2) The ventilation must be enough to minimize the...

  8. 21 CFR 888.4230 - Cement ventilation tube.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device...

  9. 46 CFR 153.316 - Special cargo pumproom ventilation rate.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Special cargo pumproom ventilation rate. 153.316 Section 153.316...Design and Equipment Cargo Handling Space Ventilation § 153.316 Special cargo pumproom ventilation rate. When Table 1 refers to...

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

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Mechanical ventilation system: General. 154.1200 Section...and Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a) Each...

  11. 49 CFR 192.187 - Vaults: Sealing, venting, and ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...false Vaults: Sealing, venting, and ventilation. 192.187 Section 192.187 ...187 Vaults: Sealing, venting, and ventilation. Each underground vault or closed...millimeters) in diameter; (2) The ventilation must be enough to minimize the...

  12. 24 CFR 3280.103 - Light and ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 false Light and ventilation. 3280.103 Section 3280.103...Considerations § 3280.103 Light and ventilation. (a) Lighting. Each habitable...whichever is greater. (b) Whole-house ventilation. Each manufactured home must be...

  13. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Ventilation and drainage. 27.1187 Section...Powerplant Fire Protection § 27.1187 Ventilation and drainage. Each compartment...installation must have provision for ventilation and drainage of flammable fluids....

  14. 33 CFR 183.630 - Standards for natural ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Standards for natural ventilation. 183.630 Section 183.630 Navigation...SAFETY BOATS AND ASSOCIATED EQUIPMENT Ventilation § 183.630 Standards for natural ventilation. (a) For the purpose of §...

  15. 46 CFR 153.316 - Special cargo pumproom ventilation rate.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Special cargo pumproom ventilation rate. 153.316 Section 153.316...Design and Equipment Cargo Handling Space Ventilation § 153.316 Special cargo pumproom ventilation rate. When Table 1 refers to...

  16. 46 CFR 111.106-15 - Ventilation of hazardous locations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation of hazardous locations. 111.106-15...Locations on OSVs § 111.106-15 Ventilation of hazardous locations. (a) The ventilation design principles must comply with...

  17. 46 CFR 127.260 - Ventilation for accommodations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation for accommodations. 127.260 ...Construction and Arrangements § 127.260 Ventilation for accommodations. (a) Each...tons must be provided with a mechanical ventilation system unless the cognizant OCMI...

  18. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Ventilation and drainage. 27.1187 Section...Powerplant Fire Protection § 27.1187 Ventilation and drainage. Each compartment...installation must have provision for ventilation and drainage of flammable fluids....

  19. 33 CFR 183.630 - Standards for natural ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Standards for natural ventilation. 183.630 Section 183.630 Navigation...SAFETY BOATS AND ASSOCIATED EQUIPMENT Ventilation § 183.630 Standards for natural ventilation. (a) For the purpose of §...

  20. 33 CFR 183.630 - Standards for natural ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Standards for natural ventilation. 183.630 Section 183.630 Navigation...SAFETY BOATS AND ASSOCIATED EQUIPMENT Ventilation § 183.630 Standards for natural ventilation. (a) For the purpose of §...

  1. 46 CFR 127.260 - Ventilation for accommodations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Ventilation for accommodations. 127.260 ...Construction and Arrangements § 127.260 Ventilation for accommodations. (a) Each...tons must be provided with a mechanical ventilation system unless the cognizant OCMI...

  2. 24 CFR 3280.103 - Light and ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 2011-04-01 false Light and ventilation. 3280.103 Section 3280.103...Considerations § 3280.103 Light and ventilation. (a) Lighting. Each habitable...whichever is greater. (b) Whole-house ventilation. Each manufactured home must be...

  3. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Mechanical ventilation system: Standards. 154.1205 Section...and Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each...

  4. 33 CFR 183.630 - Standards for natural ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Standards for natural ventilation. 183.630 Section 183.630 Navigation...SAFETY BOATS AND ASSOCIATED EQUIPMENT Ventilation § 183.630 Standards for natural ventilation. (a) For the purpose of §...

  5. 21 CFR 868.5935 - External negative pressure ventilator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false External negative pressure ventilator. 868...Therapeutic Devices § 868.5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator...

  6. 46 CFR 185.352 - Ventilation of gasoline machinery spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... false Ventilation of gasoline machinery spaces. 185.352 Section 185...185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space, required by §...

  7. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Machinery space ventilation. 111.103-3 Section...Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have...

  8. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Machinery space ventilation. 111.103-3 Section...Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have...

  9. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Machinery space ventilation. 111.103-3 Section...Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have...

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Machinery space ventilation. 111.103-3 Section...Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have...

  11. 46 CFR 185.352 - Ventilation of gasoline machinery spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... false Ventilation of gasoline machinery spaces. 185.352 Section 185...185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space, required by §...

  12. 46 CFR 185.352 - Ventilation of gasoline machinery spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... false Ventilation of gasoline machinery spaces. 185.352 Section 185...185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space, required by §...

  13. 46 CFR 185.352 - Ventilation of gasoline machinery spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... false Ventilation of gasoline machinery spaces. 185.352 Section 185...185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space, required by §...

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Machinery space ventilation. 111.103-3 Section...Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have...

  15. 46 CFR 185.352 - Ventilation of gasoline machinery spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... false Ventilation of gasoline machinery spaces. 185.352 Section 185...185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space, required by §...

  16. 49 CFR 192.173 - Compressor stations: Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Compressor stations: Ventilation. 192.173 Section...of Pipeline Components § 192.173 Compressor stations: Ventilation. Each compressor station building must be ventilated to...

  17. Guidelines for choosing face ventilation systems

    SciTech Connect

    Divers, E.F.; Volkwein, J.C.

    1987-10-01

    The authors discuss two machine-mounted face ventilation systems, a fan-powered dust scrubber and a sprayfan, for controlling dust and methane and increasing production by extending the cutting time of continuous miners. The systems are compared for a variety of considerations: installation and maintenance costs, ventilation, seam conditions, and dust control. Guidelines are given for the best use of each system.

  18. Demand Controlled Ventilation for Improved Humidity Control

    E-print Network

    Rogers, J. K.

    1996-01-01

    " the buildmg ventilation. The AIRxpert system does this by sending a signal to the building's energy management system (EMS) telling it when a zone is not adequately ventilated and needs more outside air. The EMS then takes the necessary action to get more...

  19. 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.

  20. 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. PMID:24507472

  1. Clinical review: Liberation from mechanical ventilation

    Microsoft Academic Search

    Mohamad F El-Khatib; Pierre Bou-Khalil

    2008-01-01

    Mechanical ventilation is the defining event of intensive care unit (ICU) management. Although it is a life saving intervention in patients with acute respiratory failure and other disease entities, a major goal of critical care clinicians should be to liberate patients from mechanical ventilation as early as possible to avoid the multitude of complications and risks associated with prolonged unnecessary

  2. 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.

  3. 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.

  4. Clinical review: Long-term noninvasive ventilation

    Microsoft Academic Search

    Dominique Robert; Laurent Argaud

    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

  5. Mechanical Ventilation and the Kidney

    PubMed Central

    Koyner, Jay L.; Murray, Patrick T.

    2010-01-01

    Acute lung injury (ALI) and acute kidney injury (AKI) are complications often encountered in the setting of critical illness. Both forms of end-organ injury commonly occur in similar settings of systemic inflammatory response syndrome, shock, and evolving multiple organ dysfunction. Recent elucidation of the pathobiology of critical illness has led to a more basic mechanistic understanding of the complex interplay between injured organs in patients with multiple organ dysfunction syndrome; this has been aptly called ‘the slippery slope of critical illness’ [Kidney Int Suppl 1998;66:S25–S33]. Distant organ effects of apparently isolated injuries to the lungs, gut, and kidneys have all been discovered in recent years. In this article, we will review the harmful bidirectional interaction between ALI and AKI, which appears to be a common clinical syndrome with routine clinical implications. We will review the current understanding of lung-kidney interactions from both perspectives, including the renal effects of ALI and mechanical ventilation, and the pulmonary sequelae of AKI. In this review of the emerging evidence of deleterious bidirectional organ cross talk between lung and kidney, we will focus on the role of ventilator-induced kidney injury in the pathogenesis of AKI in patients with ALI. PMID:19923815

  6. Unusual applications of noninvasive ventilation.

    PubMed

    Ambrosino, N; Guarracino, F

    2011-08-01

    The use of noninvasive ventilation (NIV) in acute hypercapnic respiratory failure, cardiogenic pulmonary oedema, acute lung injury/acute respiratory distress syndrome (ARDS), community-acquired pneumonia and weaning/post-extubation failure is considered common in clinical practice. Herein, we review the use of NIV in unusual conditions. Evidence supports the use of NIV during fibreoptic bronchoscopy, especially with high risks of endotracheal intubation (ETI), such as in immunocompromised patients. During transoesophageal echocardiography as well as in interventional cardiology and pulmonology, NIV can reduce the need for deep sedation or general anaesthesia and prevent respiratory depression induced by deep sedation. NIV may be useful after surgery, including cardiac surgery, and, with a lower level of evidence, in patients with pulmonary contusion. NIV should not be considered as an alternative to ETI in severe communicable airborne infections likely to progress to ARDS. NIV is being used increasingly as an alternative to ETI in end-stage symptomatic patients, especially to relieve dyspnoea. The role of assisted ventilation during exercise training in chronic obstructive pulmonary disease patients is still controversial. NIV should be applied under close monitoring and ETI should be promptly available in the case of failure. A trained team, careful patient selection and optimal choice of devices, can optimise outcome of NIV. PMID:21349915

  7. Improved spray fans provide ventilation solutions

    SciTech Connect

    Ruggieri, S.K.; Doyle, D.M.; Volkwein, J.C.

    1984-04-01

    The Sprayfan System is an auxiliary ventilation system. It consists of several spray manifolds strategically placed on continuous miners to effectively ventilate the immediate face area. A series of water sprays redirect the main ventilation flow to the face and sweep contaminated air (methane and dust) across the face toward the return. This improved system provides increased sweeping power across the face with a new front spray bar configuration and concentrated side power for effective face ventilation. Additional water sprays have been incorporated into the design for improved dust suppression. As with the original system, a dual-sided system is required on sections with ventilation returns on either side. To ensure proper operation, the Improved Sprayfan System requires a minimum operating pressure of 80 psi (measured at the nozzle) for most applications. Different pressure levels may be necessary to balance system power with the primary air-flow.

  8. Aggressive Blood Pressure Control Increases Coronary Heart Disease Risk Among Diabetic Patients

    PubMed Central

    Zhao, Wenhui; Katzmarzyk, Peter T.; Horswell, Ronald; Wang, Yujie; Li, Wei; Johnson, Jolene; Heymsfield, Steven B.; Cefalu, William T.; Ryan, Donna H.; Hu, Gang

    2013-01-01

    OBJECTIVE Blood pressure control can reduce the risk of coronary heart disease (CHD) among diabetic patients; however, it is not known whether the lowest risk of CHD is among diabetic patients with the lowest blood pressure level. RESEARCH DESIGN AND METHODS We performed a prospective cohort study (2000–2009) on diabetic patients including 17,536 African Americans and 12,618 whites. Cox proportional hazards regression models were used to estimate the association of blood pressure with CHD risk. RESULTS During a mean follow-up of 6.0 years, 7,260 CHD incident cases were identified. The multivariable-adjusted hazard ratios of CHD associated with different levels of systolic/diastolic blood pressure at baseline (<110/65, 110–119/65–69, 120–129/70–80, and 130–139/80–90 mmHg [reference group]; 140–159/90–100; and ?160/100 mmHg) were 1.73, 1.16, 1.04, 1.00, 1.06, and 1.11 (P trend <0.001), respectively, for African American diabetic patients, and 1.60, 1.27, 1.08, 1.00, 0.95, and 0.99 (P trend<0.001) for white diabetic patients, respectively. A U-shaped association of isolated systolic and diastolic blood pressure at baseline as well as blood pressure during follow-up with CHD risk was observed among both African American and white diabetic patients (all Ptrend <0.001). The U-shaped association was present in the younger age-group (30–49 years), and this U-shaped association changed to an inverse association in the older age-group (?60 years). CONCLUSIONS Our study suggests that there is a U-shaped or inverse association between blood pressure and the risk of CHD, and aggressive blood pressure control (blood pressure <120/70 mmHg) is associated with an increased risk of CHD among both African American and white patients with diabetes. PMID:23690530

  9. Pediatric complicated pneumonia and pneumococcal serotype replacement: trends in hospitalized children pre and post introduction of routine vaccination with Pneumococcal Conjugate Vaccine (PCV7)

    Microsoft Academic Search

    Thea K. Chibuk; Joan L. Robinson; Dawn S. Hartfield

    2010-01-01

    Recent studies have described an increase in the incidence of complicated pneumonia in children, primarily caused by Streptococcus pneumoniae. The objective of this study was to determine if the incidence of complicated pneumonias in total and due to different pneumococcal\\u000a serotypes has changed following the introduction of routine immunization with heptavalent pneumococcal conjugate vaccine (PCV7).\\u000a A retrospective review of patients

  10. 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.

  11. 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

  12. Changes in capsule and drug resistance of Pneumococci after introduction of PCV7, Japan, 2010-2013.

    PubMed

    Chiba, Naoko; Morozumi, Miyuki; Shouji, Michi; Wajima, Takeaki; Iwata, Satoshi; Ubukata, Kimiko

    2014-07-01

    We aimed to clarify changes in serotypes and genotypes mediating ?-lactam and macrolide resistance in Streptococcus pneumoniae isolates from Japanese children who had invasive pneumococcal disease (IPD) after the 7-valent pneumococcal conjugate vaccine (PCV7) was introduced into Japan; 341 participating general hospitals conducted IPD surveillance during April 2010-March 2013. A total of 300 pneumococcal isolates were collected in 2010, 146 in 2011, and 156 in 2012. The proportion of vaccine serotypes in infectious isolates decreased from 73.3% to 54.8% to 14.7% during the 3 years. Among vaccine serotype strains, genotypic penicillin-resistant S. pneumoniae strains also declined each year. Among nonvaccine serotype strains, 19A, 15A, 15B, 15C, and 24 increased in 2012. Increases were noted especially in genotypic penicillin-resistant S. pneumoniae isolates of serotypes 15A and 35B, as well as macrolide resistance mediated by the erm(B) gene in 15A, 15B, 15C, and 24. PMID:24960150

  13. 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.

  14. Closed circuit MR compatible pulsatile pump system using a ventricular assist device and pressure control unit.

    PubMed

    Lorenz, R; Benk, C; Bock, J; Stalder, A F; Korvink, J G; Hennig, J; Markl, M

    2012-01-01

    The aim of this study was to evaluate the performance of a closed circuit MR compatible pneumatically driven pump system using a ventricular assist device as pulsatile flow pump for in vitro 3D flow simulation. Additionally, a pressure control unit was integrated into the flow circuit. The performance of the pump system and its test-retest reliability was evaluated using a stenosis phantom (60% lumen narrowing). Bland-Altman analysis revealed a good test-retest reliability (mean differences = -0.016 m/s, limits of agreement = ±0.047 m/s) for in vitro flow measurements. Furthermore, a rapid prototyping in vitro model of a normal thoracic aorta was integrated into the flow circuit for a direct comparison of flow characteristics with in vivo data in the same subject. The pneumatically driven ventricular assist device was attached to the ascending aorta of the in vitro model to simulate the beating left ventricle. In the descending part of the healthy aorta a flexible stenosis was integrated to model an aortic coarctation. In vivo and in vitro comparison showed significant (P = 0.002) correlations (r = 0.9) of mean velocities. The simulation of increasing coarctation grade led to expected changes in the flow patterns such as jet flow in the post-stenotic region and increased velocities. PMID:21630351

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

    DOEpatents

    Corey, John A. (Melrose, NY)

    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.

  16. 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. PMID:17239518

  17. The Albany Medical College Ventilator Walker.

    PubMed

    Smith, T; Forrest, G; Evans, G; Johnson, R K; Chandler, N

    1996-12-01

    This report describes the design and use of a wheeled walker that can accommodate a ventilator and oxygen tanks. It is constructed of aluminum tubing. The front of the walker has receptacles to support a Mark 7 Bird Ventilator and oxygen tanks. The back end of the walker has a bench seat that is lifted to allow entry into the walker. The seat provides rigidity and stability to the frame of the walker. The walker has been used in the Medical Intensive Care Unit of the Albany Medical Center to facilitate early ambulation of patients who are ventilator dependent or who require a portable source of oxygen to begin ambulation training. PMID:8976320

  18. Position paper - primary ventilation system configuration

    SciTech Connect

    Dalpiaz, E.L.

    1994-06-01

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

  19. How to choose an anesthesia ventilator?

    PubMed

    Coisel, Y; Millot, A; Carr, J; Castagnoli, A; Pouzeratte, Y; Verzilli, D; Futier, E; Jaber, S

    2014-01-01

    During the past few years, many manufacturers have developed a new generation anesthesia ventilators or anesthesia workstations with innovative technology and introduced so-called new ventilatory modes in the operating room. The aim of this article is to briefly explain how an anesthesia ventilator works, to describe the main differences between the technologies used, to describe the main criteria for evaluating technical and pneumatic performances and to list key elements not to be forgotten during the process of acquiring an anesthesia ventilator. PMID:25138358

  20. Secretion management in the mechanically ventilated patient.

    PubMed

    Branson, Richard D

    2007-10-01

    Secretion management in the mechanically ventilated patient includes routine methods for maintaining mucociliary function, as well as techniques for secretion removal. Humidification, mobilization of the patient, and airway suctioning are all routine procedures for managing secretions in the ventilated patient. Early ambulation of the post-surgical patient and routine turning of the ventilated patient are common secretion-management techniques that have little supporting evidence of efficacy. Humidification is a standard of care and a requisite for secretion management. Both active and passive humidification can be used. The humidifier selected and the level of humidification required depend on the patient's condition and the expected duration of intubation. In patients with thick, copious secretions, heated humidification is superior to a heat and moisture exchanger. Airway suctioning is the most important secretion removal technique. Open-circuit and closed-circuit suctioning have similar efficacy. Instilling saline prior to suctioning, to thin the secretions or stimulate a cough, is not supported by the literature. Adequate humidification and as-needed suctioning are the foundation of secretion management in the mechanically ventilated patient. Intermittent therapy for secretion removal includes techniques either to simulate a cough, to mechanically loosen secretions, or both. Patient positioning for secretion drainage is also widely used. Percussion and postural drainage have been widely employed for mechanically ventilated patients but have not been shown to reduce ventilator-associated pneumonia or atelectasis. Manual hyperinflation and insufflation-exsufflation, which attempt to improve secretion removal by simulating a cough, have been described in mechanically ventilated patients, but neither has been studied sufficiently to support routine use. Continuous lateral rotation with a specialized bed reduces atelectasis in some patients, but has not been shown to improve secretion removal. Intrapulmonary percussive ventilation combines percussion with hyperinflation and a simulated cough, but the evidence for intrapulmonary percussive ventilation in mechanically ventilated patients is insufficient to support routine use. Secretion management in the mechanically ventilated patient consists of appropriate humidification and as-needed airway suctioning. Intermittent techniques may play a role when secretion retention persists despite adequate humidification and suctioning. The technique selected should remedy the suspected etiology of the secretion retention (eg, insufflation-exsufflation for impaired cough). Further research into secretion management in the mechanically ventilated patient is needed. PMID:17894902

  1. Measuring Residential Ventilation System Airflows: Part 1 Laboratory

    E-print Network

    1 Measuring Residential Ventilation System Airflows: Part 1 ­ Laboratory Evaluation of Airflow: residential, mechanical ventilation, measurement, ASHRAE 62.2, flow hood ABSTRACT Building codes increasingly require tighter homes and mechanical ventilation per ASHRAE Standard 62.2. These ventilation flows must

  2. 30 CFR 77.1911 - Ventilation of slopes and shafts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Ventilation of slopes and shafts. 77.1911...Slope and Shaft Sinking § 77.1911 Ventilation of slopes and shafts. (a) All...shafts shall be ventilated by mechanical ventilation equipment during development....

  3. 30 CFR 77.1911 - Ventilation of slopes and shafts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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

  4. THE MECHANICS OF LUNG TISSUE UNDER HIGH-FREQUENCY VENTILATION

    E-print Network

    THE MECHANICS OF LUNG TISSUE UNDER HIGH-FREQUENCY VENTILATION MARKUS R. OWEN AND MARK A. LEWIS Abstract. High frequency ventilation is a radical departure from conventional lung ventilation question concerns ventilator induced damage to the lung tissue, and a clear protocol for the most effective

  5. 30 CFR 77.1911 - Ventilation of slopes and shafts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

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

  6. 30 CFR 77.1911 - Ventilation of slopes and shafts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

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

  7. THE MECHANICS OF LUNG TISSUE UNDER HIGH-FREQUENCY VENTILATION

    E-print Network

    Lewis, Mark

    THE MECHANICS OF LUNG TISSUE UNDER HIGH-FREQUENCY VENTILATION MARKUS R. OWEN AND MARK A. LEWIS SIAM­1761 Abstract. High-frequency ventilation is a radical departure from conventional lung ventilation question concerns ventilator-induced damage to the lung tissue, and a clear protocol for the most effective

  8. Assessing Data Quality in Manual Entry of Ventilator Settings

    Microsoft Academic Search

    DAVID K. VAWDREY; REED M. GARDNER; R. SCOTT EVANS; JAMES F. ORME; TERRY P. CLEMMER; LOREN GREENWAY; FRANK A. DREWS

    2010-01-01

    Objective: To evaluate the data quality of ventilator settings recorded by respiratory therapists using a computer charting application and assess the impact of incorrect data on computerized ventilator management protocols. Design: An analysis of 29,054 charting events gathered over 12 months from 678 ventilated patients (1,736 ventilator days) in four intensive care units at a tertiary care hospital. Measurements: Ten

  9. Carbon Dioxide and Oxygen Levels in Disposable Individually Ventilated Cages after Removal from Mechanical Ventilation

    PubMed Central

    Nagamine, Claude M; Long, C Tyler; McKeon, Gabriel P; Felt, Stephen A

    2012-01-01

    Disposable individually ventilated cages have lids that restrict air exchange when the cage is not mechanically ventilated. This design feature may cause intracage CO2 to increase and O2 to decrease (hypercapnic and hypoxic conditions, respectively) when the electrical supply to the ventilated rack fails, the ventilated rack malfunctions, cages are docked in the rack incorrectly, or cages are removed from the ventilated rack for extended periods of time. We investigated how quickly hypercapnic and hypoxic conditions developed within disposable individually ventilated cages after removal from mechanical ventilation and compared the data with nondisposable static cages, disposable static cages, and unventilated nondisposable individually ventilated cages. When disposable individually ventilated cages with 5 adult mice per cage were removed from mechanical ventilation, CO2 concentrations increased from less than 1% at 0 h to approximately 5% at 3 h and O2 levels dropped from more than 20% at 0 h to 11.7% at 6 h. The breathing pattern of the mice showed a prominent abdominal component (hyperventilation). Changes were similar for 4 adult mice per cage, reaching at least 5% CO2 at 4 h and 13.0% O2 at 6 h. For 3 or 2 mice per cage, values were 4.6% CO2 and 14.7% O2 and 3.04% CO2 and 17.1% O2, respectively, at 6 h. These results document that within disposable individually ventilated cages, a hypercapnic and hypoxic microenvironment develops within hours in the absence of mechanical ventilation. PMID:22776114

  10. A Ventilation Index for Tropical Cyclones

    E-print Network

    Tang, Brian

    An important environmental control of both tropical cyclone intensity and genesis is vertical wind shear. One hypothesized pathway by which vertical shear affects tropical cyclones is midlevel ventilation—or the flux of ...

  11. Tunnel ventilation effectiveness in fire scenarios 

    E-print Network

    Colella, Francesco; Rein, Guillermo; Carvel, Ricky O; Torero, Jose L

    2010-01-01

    Throughout most of a tunnel network the ventilation behaviour may be approximated with a simple 1D flow model. However, there are some important - but relatively small - regions of the tunnel that require CFD analysis. The multi-scale model...

  12. Midlevel ventilation's constraint on tropical cyclone intensity

    E-print Network

    Tang, Brian Hong-An

    2010-01-01

    Midlevel ventilation, or the flux of low-entropy air into the inner core of a tropical cyclone (TC), is a hypothesized mechanism by which environmental vertical wind shear can constrain a TC's intensity. An idealized ...

  13. Midlevel Ventilation's Constraint on Tropical Cyclone Intensity

    E-print Network

    Tang, Brian Hong-An

    Midlevel ventilation, or the flux of low-entropy air into the inner core of a tropical cyclone (TC), is a hypothesized mechanism by which environmental vertical wind shear can constrain a tropical cyclone’s intensity. An ...

  14. 21 CFR 868.5895 - Continuous ventilator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    21 Food and Drugs 8 2014-04-01 2014-04-01...5895 Section 868.5895 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH...neonatal ventilators are included in this generic type of device. (b)...

  15. Floor-supply displacement ventilation system

    E-print Network

    Kobayashi, Nobukazu, 1967-

    2001-01-01

    Research on indoor environments has received more attention recently because reports of symptoms and other health complaints related to indoor environments have been increasing. Heating, ventilating, and air-conditioning ...

  16. 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 ...

  17. Ventilation of the Baltic Sea deep water

    E-print Network

    Mohrholz, Volker

    Sea Salt water inflows Deep water ventilation Entrainment Turbulent mixing H. E. Markus Meier1, Rainer Volker Mohrholz2 Christian Nohr4 Vadim T. Paka6 J¨urgen Sellschopp5 Adolf Stips8 Victor Zhurbas7 1

  18. Experimental Investigation on the Basic Law of Hydraulic Fracturing After Water Pressure Control Blasting

    NASA Astrophysics Data System (ADS)

    Huang, Bingxiang; Li, Pengfeng; Ma, Jian; Chen, Shuliang

    2014-07-01

    Because of the advantages of integrating water pressure blasting and hydraulic fracturing, the use of hydraulic fracturing after water pressure control blasting is a method that is used to fully transform the structure of a coal-rock mass by increasing the number and range of hydraulic cracks. An experiment to study hydraulic fracturing after water pressure blasting on cement mortar samples (300 × 300 × 300 mm3) was conducted using a large-sized true triaxial hydraulic fracturing experimental system. A traditional hydraulic fracturing experiment was also performed for comparison. The experimental results show that water pressure blasting produces many blasting cracks, and follow-up hydraulic fracturing forces blasting cracks to propagate further and to form numerous multidirectional hydraulic cracks. Four macroscopic main hydraulic cracks in total were noted along the borehole axial and radial directions on the sample surfaces. Axial and radial main failure planes induced by macroscopic main hydraulic cracks split the sample into three big parts. Meanwhile, numerous local hydraulic cracks were formed on the main failure planes, in different directions and of different types. Local hydraulic cracks are mainly of three types: local hydraulic crack bands, local branched hydraulic cracks, and axial layered cracks. Because local hydraulic cracks produce multiple local layered failure planes and lamellar ruptures inside the sample, the integrity of the sample decreases greatly. The formation and propagation process of many multidirectional hydraulic cracks is affected by a combination of water pressure blasting, water pressure of fracturing, and the stress field of the surrounding rock. To a certain degree, the stress field of surrounding rock guides the formation and propagation process of the blasting crack and the follow-up hydraulic crack. Following hydraulic fracturing that has been conducted after water pressure blasting, the integrity of the sample is found to be far lower than after traditional hydraulic fracturing; moreover, both the water injection volume and water injection pressure for hydraulic fracturing after water pressure blasting are much higher than they are for traditional hydraulic fracturing.

  19. A new pressure-controlled colon delivery capsule for chronotherapeutic treatment of nocturnal asthma.

    PubMed

    Barakat, Nahla S; Al-Suwayeh, Saleh A; Taha, Ehab I; Bakry Yassin, Alaa Eldeen

    2011-06-01

    The purpose of this study was to prepare a pressure-controlled colon delivery capsule (PCDC) containing theophylline (TPH) dispersion in a lipid matrix as a chronotherapeutic drug delivery system for the treatment of nocturnal asthma. The system was made by film coating using Eudragit S100- based formula over the sealed-hard gelatin capsules containing the drug-lipid dispersion. The lipid formula was composed mainly of Gelucire 33/01 (G33) with different ratios of surfactants (1-10%). The efficiency of the prepared system was evaluated in vitro for its ability to withstand both the gastric and intestinal medium. In addition, the drug plasma concentrations were monitored after single administration to Beagle dogs and compared to that obtained after administration of a reference marketed, generic, sustained-release TPH tablets, Avolen(®) SR. It was found that the optimum lipid formula was GL2 containing 90% G33 and 10% Labrasol. The film-coated capsules showed complete resistance to both the acidic environment (pH 1.2) for 2 hours and phosphate buffer pH 6.8 for 3 hours at 37°C. In vivo evaluation of the TPH-based PCDCs showed longer lag time compared TO the marketed formula followed by sudden increase in TPH blood levels, which recommends the high potential of this system as a chronotherapeutic drug delivery for nocturnal asthma. The prepared PCDCs exhibited a significantly higher C(max) and T(max) and a nonsignificantly different AUC compared with Avolen(®) SR. Higher TPH blood levels from 1 to 8 hours postadministration was detected in the case of the prepared PCDCs. PMID:20681754

  20. Improved Blood Pressure Control Associated With a Large-Scale Hypertension Program

    PubMed Central

    Jaffe, Marc G.; Lee, Grace A.; Young, Joseph D.; Sidney, Stephen; Go, Alan S.

    2014-01-01

    Importance Hypertension control for large populations remains a major challenge. Objective To describe a large-scale hypertension program in northern California and to compare rates of hypertension control of the program to statewide and national estimates. Design, Setting, and Patients The Kaiser Permanente Northern California (KPNC) Hypertension program included a multi-faceted approach to blood pressure control. Patients identified with hypertension within an integrated health care delivery system in northern California from 2001–2009 were included. The comparison group included insured patients in California between 2006–2009 who were included in the Healthcare Effectiveness Data and Information Set (HEDIS) commercial measurement by California health insurance plans participating in the National Committee for Quality Assurance (NQCA) quality measure reporting process. A secondary comparison group was the reported national mean NCQA HEDIS commercial rates of hypertension control from 2001–2009 from health plans that participated in the NQCA HEDIS quality measure reporting process. Main Outcome Measure Hypertension control as defined by NCQA HEDIS. Results The KPNC hypertension registry established in 2001 included 349,937 patients and grew to 652,763 by 2009. The NCQA HEDIS commercial measurement for hypertension control increased from 44% to 80% during the study period. In contrast, the national mean NCQA HEDIS commercial measurement increased modestly from 55.4% to 64.1%. California mean NCQA HEDIS commercial rates of hypertension were similar to those reported nationally from 2006–2009. (63.4% to 69.4%). Conclusion and Relevance Among adults diagnosed with hypertension, implementation of a large-scale hypertension program was associated with a significant increase in hypertension control compared with state and national control rates. PMID:23989679

  1. Machine-mounted scrubber helps ventilate face

    SciTech Connect

    Volkwein, J.C.

    1985-02-01

    The authors describe work carried out under contract for US Bureau of Mines on a machine-mounted scrubber system for ventilating the face during an extended advance. Underground tests showed that a suitable scrubber system can adequately ventilate the face at brattice setbacks up to 15m. Face methane levels were effectively controlled at large setbacks, but respirable dust levels increased by as much as 33% at the operator's cab at setbacks greater than 7.5m.

  2. Diaphragmatic Activity and Ventilation in Preterm Infants

    Microsoft Academic Search

    Francisco J. C. Reis; Donald B. Cates; Leanne V. Landriault; Henrique Rigatto

    1994-01-01

    To determine the effects of inhaled CO2 and abdominal loading on diaphragmatic electromyography (EMGdi) and ventilation during sleep, we studied 10 preterm infants (birth weight 1,840 ± 50 g; gestational age 32 ± 0.6 weeks and postnatal age 10.4 ± 1.4 days). We measured surface and esophageal diaphragmatic activity. Ventilation was measured using a nasal flowmeter and a flow-through system.

  3. Gas flow rates through transtracheal ventilation catheters

    Microsoft Academic Search

    Jonathan K Marr; Loren G Yamamoto

    2004-01-01

    The purpose of the study was to measure gas flow rates using different methods of transtracheal ventilation. Wall oxygen flow (WOF) at 10 and 15L\\/min, and a self-inflating ventilation bag (SIVB) were used to deliver gas flow through three transtracheal catheters: 13, 14, and 16 gauge (5 trials each). WOF mean gas flow rates (L\\/min) through the 16G, 14G, 13G

  4. Night ventilation control strategies in office buildings

    Microsoft Academic Search

    Zhaojun Wang; Lingli Yi; Fusheng Gao

    2009-01-01

    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

  5. Sensor-based demand controlled ventilation

    SciTech Connect

    De Almeida, A.T. [Universidade de Coimbra (Portugal). Dep. Eng. Electrotecnica; Fisk, W.J. [Lawrence Berkeley National Lab., CA (United States)

    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.

  6. Humidification of inspired gases during mechanical ventilation.

    PubMed

    Gross, J L; Park, G R

    2012-04-01

    Humidification of inspired gas is mandatory for all mechanically ventilated patients to prevent secretion retention, tracheal tube blockage and adverse changes occurring to the respiratory tract epithelium. However, the debate over "ideal" humidification continues. Several devices are available that include active and passive heat and moisture exchangers and hot water humidifiers Each have their advantages and disadvantages in mechanically ventilated patients. This review explores each device in turn and defines their role in clinical practice. PMID:22269929

  7. Recovering Energy From Ventilation and Process Airstreams

    E-print Network

    Cheney, W. A.

    RECOVERING ENERGY FROM VENTILATION AND PROCESS AIRSTREAMS Heat Exchangers and contaminant Recovery William A. Cheney united Air Specialists, Inc. Cincinnati, Ohio The high cost of energy has prompted industry to look for new ways to reduce... operating expenses. Often ignored are the large amounts of recoverable energy present in the ventilation and process airstreams discharged from the plant. The recovery methods available range from fairly simple, well-known devices that have been around...

  8. 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).

  9. 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

  10. DESIGN OF A PRESSURE CONTROL SYSTEM IN A FURNACE OF A THERMAL POWER PLANT BOILER USING SELF-TUNING IP AND FEED-FORWARD COMPENSATOR

    Microsoft Academic Search

    Takao Sato; Kazuhiro Takeda; Akira Inoue

    2007-01-01

    This paper proposes a new design method of a pressure control system in a furnace of a thermal power plant boiler. To improve the control performance of the pressure control system in a furnace controlled by using self-tuning I-P controllers, a feed-forward compensator is introduced. Simulation results are illustrated to show the effectiveness of our proposed method.

  11. Seismic qualification of ventilation stack

    SciTech Connect

    Chen, W.W.; Huang, S.N.; Lindquist, M.R.

    1993-10-01

    This paper describes the method to be used to qualify the 105 K ventilation stack at the U.S. Department of Energy`s Hanford Site, near Richland, Washington, under seismic and wind loadings. The stack stands at 175 ft (53.34 m), with a diameter tapering from 22 ft (6.71 m) at the foundation to 12.83 ft (3.91 m) at the top. Although the stack is classified as Safety Class 3 (low hazard), it is treated as a Safety Class 1 (high hazard) component, as failure could damage a Safety Class 1 facility (the irradiated fuel storage basin). The evaluation used U.S. Department of Energy criteria specified in UCRL 15910 (1990). The seismic responses of the stack under earthquake loading were obtained from modal analyses with response spectrum input that used the ANSYS (1989) finite-element computer code. The moments and shear forces from the results of seismic analysis were used to qualify the reinforcement capacity of the stack structure by the ultimate-strength method. The wind forces acting on the stack in both along-wind and crosswind directions were also calculated. Presented are evaluations of the soil bearing pressure, the moment, and the shear capacity of the stack foundation.

  12. Injurious mechanical ventilation affects neuronal activation in ventilated rats

    PubMed Central

    2011-01-01

    Introduction Survivors of critical illness often have significant long-term brain dysfunction, and routine clinical procedures like mechanical ventilation (MV) may affect long-term brain outcome. We aimed to investigate the effect of the increase of tidal volume (Vt) on brain activation in a rat model. Methods Male Sprague Dawley rats were randomized to three groups: 1) Basal: anesthetized unventilated animals, 2) low Vt (LVt): MV for three hours with Vt 8 ml/kg and zero positive end-expiratory pressure (ZEEP), and 3) high Vt (HVt) MV for three hours with Vt 30 ml/kg and ZEEP. We measured lung mechanics, mean arterial pressure (MAP), arterial blood gases, and plasma and lung levels of cytokines. We used immunohistochemistry to examine c-fos as a marker of neuronal activation. An additional group of spontaneously breathing rats was added to discriminate the effect of surgical procedure and anesthesia in the brain. Results After three hours on LVt, PaO2 decreased and PaCO2 increased significantly. MAP and compliance remained stable in MV groups. Systemic and pulmonary inflammation was higher in MV rats than in unventilated rats. Plasma TNF? was significantly higher in HVt than in LVt. Immunopositive cells to c-fos in the retrosplenial cortex and thalamus increased significantly in HVt rats but not in LVt or unventilated rats. Conclusions MV promoted brain activation. The intensity of the response was higher in HVt animals, suggesting an iatrogenic effect of MV on the brain. These findings suggest that this novel cross-talking mechanism between the lung and the brain should be explored in patients undergoing MV. PMID:21569477

  13. 10 CFR 429.43 - Commercial heating, ventilating, air conditioning (HVAC) equipment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...Commercial heating, ventilating, air conditioning (HVAC) equipment. 429...Commercial heating, ventilating, air conditioning (HVAC) equipment. Link...commercial heating, ventilating, air conditioning (HVAC) equipment,...

  14. 10 CFR 429.43 - Commercial heating, ventilating, air conditioning (HVAC) equipment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Commercial heating, ventilating, air conditioning (HVAC) equipment. 429...Commercial heating, ventilating, air conditioning (HVAC) equipment. (a...commercial heating, ventilating, air conditioning (HVAC) equipment,...

  15. 10 CFR 429.43 - Commercial heating, ventilating, air conditioning (HVAC) equipment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...Commercial heating, ventilating, air conditioning (HVAC) equipment. 429...Commercial heating, ventilating, air conditioning (HVAC) equipment. (a...commercial heating, ventilating, air conditioning (HVAC) equipment,...

  16. Design and experimental evaluation of a fuzzy logic pressure controller for the Airbus 310\\/320 braking control system

    Microsoft Academic Search

    P. J. Costa Branco; J. A. Dente

    2010-01-01

    We show here the design and preliminary experimental evaluation steps of a fuzzy controller for the pressure loop of a proposed new Airbus A310\\/A320 modular braking system. The results indicated that two main requirements of this system could be achieved:•pressure control with high robustness in the case of hydraulic load fluctuations, and;•highly modular characteristics, since the same fuzzy controller can

  17. Effects of aggressive blood pressure control in normotensive type 2 diabetic patients on albuminuria, retinopathy and strokes

    Microsoft Academic Search

    Robert W. Schrier; Raymond O. Estacio; Anne Esler; Philip Mehler

    2002-01-01

    Effects of aggressive blood pressure control in normotensive type 2 diabetic patients on albuminuria, retinopathy and strokes.BackgroundAlthough several important studies have been performed in hypertensive type 2 diabetic patients, it is not known whether lowering blood pressure in normotensive (BP <140\\/90 mm Hg) patients offers any beneficial results on vascular complications. The current study evaluated the effect of intensive versus

  18. Evaluation of anticipatory signal to steam generator pressure control program for 700 MWe Indian pressurized heavy water reactor

    SciTech Connect

    Pahari, S.; Hajela, S.; Rammohan, H. P.; Malhotra, P. K.; Ghadge, S. G. [Nuclear Power Corporation of India Limited, Nabhikiya Urja Bhavan, Anushakti Nagar, Mumbai, PIN-400094 (India)

    2012-07-01

    700 MWe Indian Pressurized Heavy Water Reactor (IPHWR) is horizontal channel type reactor with partial boiling at channel outlet. Due to boiling, it has a large volume of vapor present in the primary loops. It has two primary loops connected with the help of pressurizer surge line. The pressurizer has a large capacity and is partly filled by liquid and partly by vapor. Large vapor volume improves compressibility of the system. During turbine trip or load rejection, pressure builds up in Steam Generator (SG). This leads to pressurization of Primary Heat Transport System (PHTS). To control pressurization of SG and PHTS, around 70% of the steam generated in SG is dumped into the condenser by opening Condenser Steam Dump Valves (CSDVs) and rest of the steam is released to the atmosphere by opening Atmospheric Steam Discharge Valves (ASDVs) immediately after sensing the event. This is accomplished by adding anticipatory signal to the output of SG pressure controller. Anticipatory signal is proportional to the thermal power of reactor and the proportionality constant is set so that SG pressure controller's output jacks up to ASDV opening range when operating at 100% FP. To simulate this behavior for 700 MWe IPHWR, Primary and secondary heat transport system is modeled. SG pressure control and other process control program have also been modeled to capture overall plant dynamics. Analysis has been carried out with 3-D neutron kinetics coupled thermal hydraulic computer code ATMIKA.T to evaluate the effect of the anticipatory signal on PHT pressure and over all plant dynamics during turbine trip in 700 MWe IPHWR. This paper brings out the results of the analysis with and without considering anticipatory signal in SG pressure control program during turbine trip. (authors)

  19. Episodic ventilation lowers the efficiency of pulmonary CO2 excretion.

    PubMed

    Malte, Christian Lind; Malte, Hans; Wang, Tobias

    2013-11-01

    The ventilation pattern of many ectothermic vertebrates, as well as hibernating and diving endotherms, is episodic where breaths are clustered in bouts interspersed among apneas of varying duration. Using mechanically ventilated, anesthetized freshwater turtles (Trachemys scripta), a species that normally exhibits this episodic ventilation pattern, we investigated whether episodic ventilation affects pulmonary gas exchange compared with evenly spaced breaths. In two separate series of experiments (a noninvasive and an invasive), ventilation pattern was switched from a steady state, with evenly spaced breaths, to episodic ventilation while maintaining overall minute ventilation (30 ml·min(-1)·kg(-1)). On switching to an episodic ventilation pattern of 10 clustered breaths, mean CO2 excretion rate was reduced by 6 ± 5% (noninvasive protocol) or 20 ± 8% (invasive protocol) in the first ventilation pattern cycle, along with a reduction in the respiratory exchange ratio. O2 uptake was either not affected or increased in the first ventilation pattern cycle, while neither heart rate nor overall pulmonary blood flow was significantly affected by the ventilation patterns. The results confirm that, for a given minute ventilation, episodic ventilation is intrinsically less efficient for CO2 excretion, thereby indicating an increase in the total bodily CO2 store in the protocol. Despite the apparent CO2 retention, mean arterial Pco2 only increased 1 Torr during the episodic ventilation pattern, which was concomitant with a possible reduction of respiratory quotient. This would indicate a shift in metabolism such that less CO2 is produced when the efficiency of excretion is reduced. PMID:23970538

  20. 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.

  1. 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.

  2. 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 patient and operating personnel, and physiological considerations. The simple schematic, comprised of easily acquired commercial hardware, supports sustainability.

  3. 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, supports sustainability.

  4. 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 reasonably achievable) principles to maintain personnel radiation doses to all occupational workers below regulatory limits and as low as is reasonably achievable. The Waste Handling Building Ventilation System interfaces with the Waste Handling Building System by being located within the WHB and by maintaining specific pressures, temperatures, and humidity within the building. The system also depends on the WHB for water supply. The system interfaces with the Site Radiological Monitoring System for continuous monitoring of the exhaust air; the Waste Handling Building Fire Protection System for detection of fire and smoke; the Waste Handling Building Electrical System for normal, emergency, and standby power; and the Monitored Geologic Repository Operations Monitoring and Control System for monitoring and control of the system.

  5. 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.

  6. Efficacy of intermittent ventilation for providing acceptable indoor air quality

    SciTech Connect

    Sherman, M.H.

    2004-10-01

    Ventilation standards and guidelines typically treat ventilation as a constant and specify its value. In many circumstances a designer wishes to use intermittent ventilation, rather than constant ventilation, but there are no easy equivalencies available. This report develops a model of efficacy that allows one to calculate how much intermittent ventilation one needs to get the same indoor air quality as a the continuous value specified. We have found that there is a simple relationship between three dimensionless quantities: the temporal ventilation effectiveness (which we call the efficacy), the nominal turn-over and the under-ventilation fraction. This relationship allows the calculation of intermittent ventilation for a wide variety of parameters and conditions. We can use the relationship to define a critical time that separates the regime in which ventilation variations can be averaged over from the regime in which variable ventilation is of low effectiveness. We have found that ventilation load-shifting, temporary protection against poor outdoor air quality and dynamic ventilation strategies can be quite effective in low-density buildings such as single-family houses or office spaces. The results of this work enable ventilation standards and guidelines to allow this extra flexibility and still provide acceptable indoor air quality.

  7. 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. PMID:24950783

  8. 30 CFR 57.8531 - Construction and maintenance of ventilation doors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Construction and maintenance of ventilation doors. 57.8531 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8531 Construction and maintenance of ventilation doors. Ventilation doors...

  9. 30 CFR 57.8531 - Construction and maintenance of ventilation doors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Construction and maintenance of ventilation doors. 57.8531 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8531 Construction and maintenance of ventilation doors. Ventilation doors...

  10. 30 CFR 57.8531 - Construction and maintenance of ventilation doors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Construction and maintenance of ventilation doors. 57.8531 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8531 Construction and maintenance of ventilation doors. Ventilation doors...

  11. 30 CFR 57.8531 - Construction and maintenance of ventilation doors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Construction and maintenance of ventilation doors. 57.8531 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8531 Construction and maintenance of ventilation doors. Ventilation doors...

  12. 30 CFR 57.8531 - Construction and maintenance of ventilation doors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Construction and maintenance of ventilation doors. 57.8531 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground Only § 57.8531 Construction and maintenance of ventilation doors. Ventilation doors...

  13. Pulmonary ventilation teaching aid: part 2

    NSDL National Science Digital Library

    PhD Brad Stockert (University of the Pacific Department of Physical Therapy)

    2003-06-01

    Since writing the article titled "Pulmonary ventilation teaching aid" (Stockert B, Adv Physiol Educ 27: 41Â?42, 2003), we have continued to use the salad tongs and rubber band model to teach ventilation mechanics and several clinical correlates. The original article dealt primarily with normal ventilation mechanics and changes in the lungs, i.e., the rubber bands, that occur with common pulmonary disorders, e.g., pulmonary fibrosis and chronic obstructive pulmonary disease. We have developed several additional clinical correlates related to changes in the chest wall, i.e., the salad tongs. Those clinical examples are presented here. The materials needed for this demonstration are several rubber bands and a pair of metal salad tongs with a hinge.

  14. 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

  15. 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. PMID:24674617

  16. 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.

  17. 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.

  18. Natural ventilation typologies of large buildings

    SciTech Connect

    Cook, J. [Arizona State Univ., Tempe, AZ (United States); Littler, J. [Univ. of Westminster, London (United Kingdom). School of Architecture and Civil Engineering

    1996-10-01

    Building design concepts as informed by architectural ventilation are defined in a review of recently constructed large buildings in Britain and Africa. All have a narrow floor plan width based on both daylighting and natural ventilation, providing access to the air and light of the outdoor environment at the perimeter wall. Exhaust strategy distinguishes the different types three dimensionally, producing a variety of spatial configurations or architectural typologies. In conclusion, natural ventilation as a compatible strategy with daylighting is a viable and growing practice that is developing a new architectural genre. But the necessary integration of architecture and services requires exceptional collaboration and coordination between architect and engineer/consultant. The buildings examined include Powergen, Coventry: [linear extruded atrium]; Ionica, Cambridge; and De Montfort Engineering Building, Leicester: [shaped atrium]; Anglia Resource Center, Chelmsford: [central atrium]; St. Johns College Library, Cambridge: [central exhaust tower]; Eastgate, Harare, Zimbabwe: [central ducted exhaust flues]; and Inland Revenue, Nottingham: [exhaust towers at ends].

  19. 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.

  20. Study on Influencing Factors of Night Ventilation in Office Rooms

    E-print Network

    Wang, Z.; Sun, X.

    2006-01-01

    A mathematical and physical model on night ventilation is set up. The fields of indoor air temperature, air velocity and thermal comfort are simulated using Airpak software. Some main influencing factors of night ventilation in office rooms...

  1. 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)

  2. Analyzing Ventilation Effects of Different Apartment Styles by CFD

    E-print Network

    Li, X.; Wang, L.; Ye, Z.

    2006-01-01

    in different directions have distinct ventilation environments. By compare the velocity fields of each apartment in four directions, results show that the apartment in the east has favorable ventilation effects. There are some disadvantages of other apartments...

  3. Design of a Natural Ventilation System in the Dunhuang Museum

    E-print Network

    Zhang, Y.; Guan, W.

    2006-01-01

    Fresh air and good air quality can be obtained by a natural ventilation system, to fulfill the requirement of near natural conditions for the psychological health of mankind. A natural ventilation system is an ecological, energy saving system...

  4. Modeling buoyancy-driven airflow in ventilation shafts

    E-print Network

    Ray, Stephen D. (Stephen Douglas)

    2012-01-01

    Naturally ventilated buildings can significantly reduce the required energy for cooling and ventilating buildings by drawing in outdoor air using non-mechanical forces. Buoyancy-driven systems are common in naturally ...

  5. Study of natural ventilation in buildings with large eddy simulation

    E-print Network

    Jiang, Yi, 1972-

    2002-01-01

    With the discovery of many economic, environmental, and health problems in sealed and mechanically ventilated buildings, the concept of natural ventilation has been revived. "Buildings that breathe" have become more and ...

  6. 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

  7. A scale model study of displacement ventilation with chilled ceilings

    E-print Network

    Holden, Katherine J. A. (Katherine Joan Adrienne)

    1995-01-01

    Displacement ventilation is a form of air-conditioning which provides good air quality and some energy savings. The air quality is better than for a conventional mixed ventilation system. The maximum amount of cooling that ...

  8. USE OF NATURAL VENTILATION TO CONTROL RADON IN SINGLE FAMILYDWELLINGS

    EPA Science Inventory

    The paper discusses an examination of a fundamental assumption inradon mitigation work, that natural ventilation is not veryeffective in lowering indoor radon levels in buildings. Themechanism by which ventilation acted to reduce radon levels wasconsidered to be simple dilution; ...

  9. 49 CFR 192.173 - Compressor stations: Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Compressor stations: Ventilation...TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM... § 192.173 Compressor stations: Ventilation. Each compressor station building...accumulation of gas in rooms,...

  10. 49 CFR 192.173 - Compressor stations: Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Compressor stations: Ventilation...TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM... § 192.173 Compressor stations: Ventilation. Each compressor station building...accumulation of gas in rooms,...

  11. 49 CFR 192.173 - Compressor stations: Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Compressor stations: Ventilation...TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM... § 192.173 Compressor stations: Ventilation. Each compressor station building...accumulation of gas in rooms,...

  12. 49 CFR 192.173 - Compressor stations: Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Compressor stations: Ventilation...TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM... § 192.173 Compressor stations: Ventilation. Each compressor station building...accumulation of gas in rooms,...

  13. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...108.181 Section 108.181 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for...

  14. 46 CFR 108.185 - Ventilation for enclosed classified locations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...108.185 Section 108.185 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Ventilation § 108.185 Ventilation for...

  15. 46 CFR 108.185 - Ventilation for enclosed classified locations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...108.185 Section 108.185 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Ventilation § 108.185 Ventilation for...

  16. 46 CFR 78.47-53 - Automatic ventilation dampers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...ventilation dampers. (a) The manual operating positions for automatic fire dampers in ventilation ducts passing through main vertical zone bulkheads shall be identified by red day light-reflecting letters at least 1/2 inch high...

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Cargo Area: Mechanical Ventilation...control station, and other gas-safe spaces. ...ventilation system for a gas-safe cargo control station in the cargo area must change the air...

  18. Post-Polio Health International including International Ventilator Users Network

    MedlinePLUS

    ... post-polio.org. Check out International Ventilator Users Network Post-Polio Health International's mission is to enhance ... Polio Health International (PHI) Including International Ventilator Users Network 4207 Lindell Blvd., #110, Saint Louis, MO 63108- ...

  19. 30 CFR 77.1106 - Battery-charging stations; ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 2014-07-01 2014-07-01 false Battery-charging stations; ventilation. 77...COAL MINES Fire Protection § 77.1106 Battery-charging stations; ventilation. Battery-charging stations shall be located in...

  20. 30 CFR 77.1106 - Battery-charging stations; ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 2012-07-01 2012-07-01 false Battery-charging stations; ventilation. 77...COAL MINES Fire Protection § 77.1106 Battery-charging stations; ventilation. Battery-charging stations shall be located in...

  1. 30 CFR 77.1106 - Battery-charging stations; ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 2013-07-01 2013-07-01 false Battery-charging stations; ventilation. 77...COAL MINES Fire Protection § 77.1106 Battery-charging stations; ventilation. Battery-charging stations shall be located in...

  2. 30 CFR 77.1106 - Battery-charging stations; ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2010-07-01 2010-07-01 false Battery-charging stations; ventilation. 77...COAL MINES Fire Protection § 77.1106 Battery-charging stations; ventilation. Battery-charging stations shall be located in...

  3. 30 CFR 77.1106 - Battery-charging stations; ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 2011-07-01 2011-07-01 false Battery-charging stations; ventilation. 77...COAL MINES Fire Protection § 77.1106 Battery-charging stations; ventilation. Battery-charging stations shall be located in...

  4. Variable ventilation induces endogenous surfactant release in normal guinea pigs

    E-print Network

    Lutchen, Kenneth

    Variable ventilation induces endogenous surfactant release in normal guinea pigs Stephen P. Arold,1. Alencar, Kenneth R. Lutchen, and Edward P. Ingenito. Variable ventilation induces endogenous surfactant lavage for determination of alveolar surfactant content and composition, while protein content

  5. 24 CFR 3280.710 - Venting, ventilation and combustion air.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... false Venting, ventilation and combustion air. 3280.710 Section 3280...3280.710 Venting, ventilation and combustion air. (a) The venting as required...manufacturer's instructions. (b) Venting and combustion air systems shall be installed in...

  6. 24 CFR 3280.710 - Venting, ventilation and combustion air.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... false Venting, ventilation and combustion air. 3280.710 Section 3280...3280.710 Venting, ventilation and combustion air. (a) The venting as required...manufacturer's instructions. (b) Venting and combustion air systems shall be installed in...

  7. 24 CFR 3280.710 - Venting, ventilation and combustion air.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... false Venting, ventilation and combustion air. 3280.710 Section 3280...3280.710 Venting, ventilation and combustion air. (a) The venting as required...manufacturer's instructions. (b) Venting and combustion air systems shall be installed in...

  8. 24 CFR 3280.710 - Venting, ventilation and combustion air.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... false Venting, ventilation and combustion air. 3280.710 Section 3280...3280.710 Venting, ventilation and combustion air. (a) The venting as required...manufacturer's instructions. (b) Venting and combustion air systems shall be installed in...

  9. 24 CFR 3280.710 - Venting, ventilation and combustion air.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... false Venting, ventilation and combustion air. 3280.710 Section 3280...3280.710 Venting, ventilation and combustion air. (a) The venting as required...manufacturer's instructions. (b) Venting and combustion air systems shall be installed in...

  10. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Machinery space, ventilation. 58.01-45...MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each...

  11. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Machinery space, ventilation. 58.01-45...MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each...

  12. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation (other than machinery spaces). 169.315 Section 169.315 Shipping ...Hull Structure § 169.315 Ventilation (other than machinery spaces). (a) All enclosed spaces within the...

  13. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Machinery space, ventilation. 58.01-45...MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each...

  14. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation (other than machinery spaces). 169.315 Section 169.315 Shipping ...Hull Structure § 169.315 Ventilation (other than machinery spaces). (a) All enclosed spaces within the...

  15. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation (other than machinery spaces). 169.315 Section 169.315 Shipping ...Hull Structure § 169.315 Ventilation (other than machinery spaces). (a) All enclosed spaces within the...

  16. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Machinery space, ventilation. 58.01-45...MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each...

  17. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation (other than machinery spaces). 169.315 Section 169.315 Shipping ...Hull Structure § 169.315 Ventilation (other than machinery spaces). (a) All enclosed spaces within the...

  18. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Ventilation (other than machinery spaces). 169.315 Section 169.315 Shipping ...Hull Structure § 169.315 Ventilation (other than machinery spaces). (a) All enclosed spaces within the...

  19. Ways of improving economy and reliability of mine ventilation

    SciTech Connect

    N.N. Petrov; N.A. Popov [Russian Academy of Sciences, Novosibirsk (Russian Federation). Institute of Mining

    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.

  20. 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.

  1. 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.

  2. Effect of repository underground ventilation on emplacement drift temperature control

    SciTech Connect

    Yang, H.; Sun, Y.; McKenzie, D.G.; Bhattacharyya, K.K. [Morrison Knudson Corporation, Las Vegas, NV (United States)

    1996-02-01

    The repository advanced conceptual design (ACD) is being conducted by the Civilian Radioactive Waste Management System, Management & Operating Contractor. Underground ventilation analyses during ACD have resulted in preliminary ventilation concepts and design methodologies. This paper discusses one of the recent evaluations -- effects of ventilation on emplacement drift temperature management.

  3. Cytokines and ventilator-induced acute lung injury

    Microsoft Academic Search

    Bing HAN; Mingyao LIU

    2002-01-01

    Mechanical ventilation is an indispensable therapy for patients who need respiratory support. However, im- proper ventilation can lead to acute lung injury, which contributes to the mortality and morbidity of patients with respiratory distress. Mechanical ventilator-induced production of pro-inflammatory mediators, such as cytokines and chemokines, has been suggested to play an important role in mediating acute inflammatory responses in the

  4. Should Title 24 Ventilation Requirements Be Amended to

    E-print Network

    Should Title 24 Ventilation Requirements Be Amended to include an Indoor Air Quality Procedure Ventilation Requirements Be Amended to include an Indoor Air Quality Procedure? William J. Fisk, Spencer M Berkeley, CA 94720 May 10, 2013 ABSTRACT Minimum outdoor air ventilation rates (VRs) for buildings

  5. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

  6. STATE OF CALIFORNIA INDOOR AIR QUALITY AND MECHANICAL VENTILATION

    E-print Network

    STATE OF CALIFORNIA INDOOR AIR QUALITY AND MECHANICAL VENTILATION CEC- CF-6R-MECH-05 (Revised 08 Ventilation (Page 1 of 7) Site Address: Enforcement Agency: Permit Number: 2008 Residential Compliance Forms August 2009 Ventilation for Indoor Air Quality (IAQ): All dwelling units shall meet the requirements

  7. RECOMMENDED VENTILATION STRATEGIES FOR ENERGY-EFFICIENT PRODUCTION HOMES

    E-print Network

    LBNL-40378 UC-000 RECOMMENDED VENTILATION STRATEGIES FOR ENERGY-EFFICIENT PRODUCTION HOMES Judy A of Energy under Contract No. DE-AC03-76SF00098. #12;i Abstract This report evaluates residential ventilation mechanical ventilation strategies for new, low-infiltration, energy-efficient, single-family, ENERGY STAR

  8. Validation of CFD Simulations for Natural Ventilation , Camille Allocca1

    E-print Network

    Chen, Qingyan "Yan"

    1 Validation of CFD Simulations for Natural Ventilation Yi Jiang1 , Camille Allocca1 , and Qingyan ventilation, which may provide occupants with good indoor air quality and a high level of thermal comfort-driven and buoyancy-drive natural ventilation. The validation of the CFD models used the experimental data of wind

  9. Natural Ventilation Design for Houses in Thailand Chalermwat Tantasavasdia

    E-print Network

    Chen, Qingyan "Yan"

    1 Natural Ventilation Design for Houses in Thailand Chalermwat Tantasavasdia , Jelena Srebricb This paper explores the potential of using natural ventilation as a passive cooling system for new house conditions in Bangkok, the study found that it is possible to use natural ventilation to create a thermally

  10. Contribution of Gular Pumping to Lung Ventilation in Monitor

    E-print Network

    Brainerd, Elizabeth

    Contribution of Gular Pumping to Lung Ventilation in Monitor Lizards Tomasz Owerkowicz,1 * Colleen that lizards are subject to a speed- dependent axial constraint that prevents effective lung ventilation during locomotion, varanids use a positive pressure gular pump to assist lung ventilation. Disabling the gular pump

  11. Improved Wireless Performance from Mode Scattering in Ventilation Ducts

    E-print Network

    Stancil, Daniel D.

    Improved Wireless Performance from Mode Scattering in Ventilation Ducts Benjamin E. Henty, PA 15230. henty@eirp.org and stancil@cmu.edu Abstract Ventilation ducts are a convenient present in a ventilation duct T-junction and note with some surprise that improvement in the performance

  12. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation for enclosed spaces. 127.250 ...Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each...be provided for stopping each fan in a ventilation system serving machinery and cargo...

  13. LBNL REPORT NUMBER 53776; OCTOBER 2003 ASHRAE &Residential Ventilation

    E-print Network

    LBNL REPORT NUMBER 53776; OCTOBER 2003 ASHRAE &Residential Ventilation Max Sherman Energy of heating, ventilating, air-conditioning and refrigeration (HVAC&R). ASHRAE has recently released a new residential ventilation standard reflecting minimum requirements for homes. They have also released a top ten

  14. "Passive Ventilation in a Simple Structure" Thomas Rogg

    E-print Network

    Mountziaris, T. J.

    "Passive Ventilation in a Simple Structure" Thomas Rogg Faculty Mentor: Dr. Scott Civjan, Civil & Environmental Engineering The research concept is to investigate the addition of a passive ventilation system in a greener and more efficient ventilation system. The project is in the very early stages and I have been

  15. 46 CFR 78.47-75 - Ventilation alarm failure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation alarm failure. 78.47-75 Section...Equipment, Etc. § 78.47-75 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

  16. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation for enclosed spaces. 127.250 ...Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each...be provided for stopping each fan in a ventilation system serving machinery and cargo...

  17. Measuring Residential Ventilation System Airflows: Part 2 -Field

    E-print Network

    1 Measuring Residential Ventilation System Airflows: Part 2 - Field Evaluation of Airflow Meter Residential Ventilation System Airflows: Part 2 - Field Evaluation of Airflow Meter Devices and System Flow, mechanical ventilation, measurement, ASHRAE 62.2, flow hood ABSTRACT The 2008 California State Energy Code

  18. AIR FLOW MODELING IN DEEP WELLS: APPLICATION TO MINING VENTILATION

    E-print Network

    Johansson, Karl Henrik

    AIR FLOW MODELING IN DEEP WELLS: APPLICATION TO MINING VENTILATION E. WITRANT1, K.H. JOHANSSON2. Introduction Traditionally, the control of large-scale systems, such as mining ventilation, has been performed to the preliminary design of the global system and automation devices. Mining ventilation provides for an interesting

  19. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

  20. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation for enclosed spaces. 127.250 ...Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each...be provided for stopping each fan in a ventilation system serving machinery and cargo...