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1

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

PubMed Central

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

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

2014-01-01

2

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

PubMed Central

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

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

2014-01-01

3

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

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

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

2011-01-01

4

A comparison between volume-controlled ventilation and pressure-controlled ventilation in providing better oxygenation in obese patients undergoing laparoscopic cholecystectomy  

PubMed Central

Background: The maintenance of oxygenation is a commonly encountered problem in obese patients undergoing laparoscopic cholecystectomy. There is no specific guideline on the ventilation modes for this group of patients. Although several studies have been performed to determine the optimal ventilatory settings in these patients, the answer is yet to be found. The aim of this study was to evaluate the efficacy of pressure-controlled ventilation (PCV) in comparison with volume-controlled ventilation (VCV) for maintaining oxygenation during laparoscopic cholecystectomy in obese patients. Methods: One hundred and two adult patients of ASA physical status I and II, Body Mass Index of 30–40 kg/m2, scheduled for laparoscopic cholecystectomy were included in this prospective randomized open-label parallel group study. To start with, all patients received VCV. Fifteen minutes after creation of pneumoperitoneum, they were randomized to receive either VCV (Group V) or PCV (Group P). The ventilatory parameters were adjusted accordingly to maintain the end-tidal CO2 between 35 and 40 mmHg. Respiratory rate, tidal volume, minute ventilation and peak airway pressure were noted. Arterial blood gas analyses were done 15 min after creation of pneumoperitoneum and at 20-min intervals thereafter till the end of the surgery. All data were analysed statistically. Results: Patients in Group P showed a statistically significant (P < 0.05) higher level of PaO2 and lower value of PAO2–PaO2 than those in Group V. Conclusion: PCV is a more effective mode of ventilation in comparison with VCV regarding oxygenation in obese patients undergoing laparoscopic cholecystectomy. PMID:22923828

Gupta, Sampa Dutta; Kundu, Sudeshna Bhar; Ghose, Tapas; Maji, Sunanda; Mitra, Koel; Mukherjee, Maitreyee; Mandal, Sripurna; Sarbapalli, Debabrata; Bhattacharya, Sulagna; Bhattacharya, Saikat

2012-01-01

5

A new design for high stability pressure-controlled ventilation for small animal lung imaging  

NASA Astrophysics Data System (ADS)

We have developed a custom-designed ventilator to deliver a stable pressure to the lungs of small animals for use in imaging experiments. Our ventilator was designed with independent pressure vessels to separately control the Peak Inspiratory Pressure (PIP) and Positive End Expiratory Pressure (PEEP) to minimise pressure fluctuations during the ventilation process. The ventilator was computer controlled through a LabVIEW interface, enabling experimental manipulations to be performed remotely whilst simultaneously imaging the lungs in situ. Mechanical ventilation was successfully performed on newborn rabbit pups to assess the most effective ventilation strategies for aerating the lungs at birth. Highly stable pressures enabled reliable respiratory gated acquisition of projection radiographs and a stable prolonged (15 minute) breath-hold for high-resolution computed tomography of deceased rabbit pups at different lung volumes.

Kitchen, M. J.; Habib, A.; Fouras, A.; Dubsky, S.; Lewis, R. A.; Wallace, M. J.; Hooper, S. B.

2010-02-01

6

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

PubMed Central

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

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

2014-01-01

7

Pneumococcal Vaccines (PCV, PPSV)  

MedlinePLUS

... to Expect Ebola: What to Know Your Child's Immunizations: Pneumococcal Vaccines (PCV, PPSV) KidsHealth > Parents > General Health > ... also helps stop the spread of the infection. Immunization Schedule PCV immunizations are given as a series ...

8

PCV valve flutter : vibration characterization through pressure and flow  

E-print Network

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 ...

Gomez, Nicasio

2005-01-01

9

Anaesthesia ventilators.  

PubMed

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

Jain, Rajnish K; Swaminathan, Srinivasan

2013-09-01

10

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

PubMed Central

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

2014-01-01

11

FISH in polycythemia vera (PCV)  

SciTech Connect

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

Amiel, A.; Gaber, E.; Manor, Y. [Meir General Hospital, Kfar-Saba (Israel)] [and others

1994-09-01

12

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

PubMed Central

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

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

2014-01-01

13

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

PubMed Central

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

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

2006-01-01

14

Pathogenesis of PCV2a and PCV2b virus in germ-free pigs  

Technology Transfer Automated Retrieval System (TEKTRAN)

Genetic analysis of porcine circovirus type 2 (PCV2) reveals 2 subgroups that will be referred to as PCV2a and PCV2b representing the North American and European prototypes respectfully. This paper summarizes 3 studies comparing the pathogenesis of 2a and 2b viruses in germ-free pigs. In this PCV2...

15

Sustained inflation and incremental mean airway pressure trial during conventional and high-frequency oscillatory ventilation in a large porcine model of acute respiratory distress syndrome  

PubMed Central

Background To compare the effect of a sustained inflation followed by an incremental mean airway pressure trial during conventional and high-frequency oscillatory ventilation on oxygenation and hemodynamics in a large porcine model of early acute respiratory distress syndrome. Methods Severe lung injury (Ali) was induced in 18 healthy pigs (55.3 ± 3.9 kg, mean ± SD) by repeated saline lung lavage until PaO2 decreased to less than 60 mmHg. After a stabilisation period of 60 minutes, the animals were randomly assigned to two groups: Group 1 (Pressure controlled ventilation; PCV): FIO2 = 1.0, PEEP = 5 cmH2O, VT = 6 ml/kg, respiratory rate = 30/min, I:E = 1:1; group 2 (High-frequency oscillatory ventilation; HFOV): FIO2 = 1.0, Bias flow = 30 l/min, Amplitude = 60 cmH2O, Frequency = 6 Hz, I:E = 1:1. A sustained inflation (SI; 50 cmH2O for 60s) followed by an incremental mean airway pressure (mPaw) trial (steps of 3 cmH2O every 15 minutes) were performed in both groups until PaO2 no longer increased. This was regarded as full lung inflation. The mPaw was decreased by 3 cmH2O and the animals reached the end of the study protocol. Gas exchange and hemodynamic data were collected at each step. Results The SI led to a significant improvement of the PaO2/FiO2-Index (HFOV: 200 ± 100 vs. PCV: 58 ± 15 and TAli: 57 ± 12; p < 0.001) and PaCO2-reduction (HFOV: 42 ± 5 vs. PCV: 62 ± 13 and TAli: 55 ± 9; p < 0.001) during HFOV compared to lung injury and PCV. Augmentation of mPaw improved gas exchange and pulmonary shunt fraction in both groups, but at a significant lower mPaw in the HFOV treated animals. Cardiac output was continuously deteriorating during the recruitment manoeuvre in both study groups (HFOV: TAli: 6.1 ± 1 vs. T75: 3.4 ± 0.4; PCV: TAli: 6.7 ± 2.4 vs. T75: 4 ± 0.5; p < 0.001). Conclusion A sustained inflation followed by an incremental mean airway pressure trial in HFOV improved oxygenation at a lower mPaw than during conventional lung protective ventilation. HFOV but not PCV resulted in normocapnia, suggesting that during HFOV there are alternatives to tidal ventilation to achieve CO2-elimination in an "open lung" approach. PMID:16792808

Muellenbach, Ralf M; Kredel, Markus; Zollhoefer, Bernd; Wunder, Christian; Roewer, Norbert; Brederlau, Joerg

2006-01-01

16

Blood Pressure Control  

NASA Technical Reports Server (NTRS)

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.

1986-01-01

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

Effect of Porcine Circovirus Type 2 (PCV2) Vaccination of the Dam on PCV2 Replication In Utero?  

PubMed Central

The aims of this study were to determine if porcine circovirus type 2 (PCV2) vaccination of the dam is effective in preventing fetal PCV2 infection and reproductive failure. Twelve pregnant, PCV2-naïve sows were randomly divided into four groups, with three sows in each group. Group 1 sows served as noninoculated, nonvaccinated negative controls, group 2 sows were vaccinated with a commercially available PCV2 vaccine at 28 days of gestation and were not inoculated, group 3 sows were vaccinated at 28 days of gestation and inoculated with PCV2b at 56 days of gestation, and group 4 sows were inoculated with PCV2b but were not vaccinated. Serum samples from all sows were collected weekly throughout the gestation period, and sows were allowed to farrow naturally. At parturition, sow colostrum samples, presuckle serum samples, and tissues from the piglets were collected. Reproductive failure was not observed under the study conditions. PCV2 vaccination induced PCV2-specific immunoglobulin G and serum neutralizing antibodies in sows from groups 2 and 3 and prevented detectable PCV2 viremia in the dams after challenge. In group 3, PCV2 DNA was detected in colostrum samples, fetuses, and live-born pigs; however, microscopic lesions and PCV2-specific antigen were not present in any of the fetuses in this group. The results from this study indicate that vertical transmission of PCV2 can occur in PCV2-vaccinated dams. PMID:19357312

Madson, D. M.; Patterson, A. R.; Ramamoorthy, S.; Pal, N.; Meng, X. J.; Opriessnig, T.

2009-01-01

19

Reproduction in porcine circovirus type 2 (PCV2) seropositive gilts inseminated with PCV2b spiked semen  

PubMed Central

Background Since 1999, field evidence of transplacental infection by porcine circovirus type 2 (PCV2) and reproductive failure has been reported in pigs. The objective of this study was to evaluate the clinical and pathological consequences of PCV2 infection in conventional PCV2-seropositive gilts by insemination with PCV2b-spiked semen. Results Six PCV2 seropositive gilts were inseminated with PCV2b-supplemented semen (infected) and three animals with semen and cell culture medium (controls). Only three out of the six infected animals were pregnant by ultrasonography on day 29 after insemination, while two out of the three controls were pregnant. One control gilt aborted on day 23 after insemination but not due to PVC2. Viraemia was demonstrated in four out of six infected and in one control gilt that became infected with PCV2a. Anti-PCV2 antibody titres showed dynamic variations in the infected group throughout the study. Among infected gilts, the animal with the lowest anti-PCV2 titre (1/100) at the beginning of the experiment and another that reached a similar low value during the experiment showed evident seroconversion over time and had also PCV2 positive foetuses. One placenta displayed mild focal necrosis of the chorionic epithelium positively stained by immunohistochemistry for PCV2 antigen. Conclusions PCV2-seropositive gilts can be infected with PCV2 after intrauterine exposure and low maternal antibody titre may increase the probability of a foetal infection. PMID:22935352

2012-01-01

20

Differentiation of porcine circovirus (PCV)-1 and PCV2 in boar semen using a multiplex nested polymerase chain reaction  

Microsoft Academic Search

A multiplex nested polymerase chain reaction (PCR) was developed for the detection of and differentiation between porcine circovirus (PCV)-1 and PCV-2 in boar semen. Eighteen (30%) and 30 (50%) out of 60 whole semen samples were found to be positive for PCV using multiplex conventional PCR and multiplex nested PCR, respectively. Of the 30 positive samples obtained using multiplex nested

Junghyun Kim; Dong Un Han; Changsun Choi; Chanhee Chae

2001-01-01

21

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

PubMed

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

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

2014-09-17

22

Ventilation and ventilators.  

PubMed

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

Hayes, B

1982-01-01

23

Comparative Effects of Vaccination against Porcine Circovirus Type 2 (PCV2) and Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) in a PCV2-PRRSV Challenge Model  

PubMed Central

The objective of the present study was to determine the effects of porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) vaccinations in an experimental PCV2-PRRSV challenge model, based on virological (viremia), immunological (neutralizing antibodies [NAs], gamma interferon-secreting cells [IFN-?-SCs], and CD4+ CD8+ double-positive cells), and pathological (lesions and antigens in lymph nodes and lungs) evaluations. A total of 72 pigs were randomly divided into 9 groups (8 pigs per group): 5 vaccinated and challenged groups, 3 nonvaccinated and challenged groups, and a negative-control group. Vaccination against PCV2 induced immunological responses (NAs and PCV2-specific IFN-?-SCs) and reduced PCV2 viremia, PCV2-induced lesions, and PCV2 antigens in the dually infected pigs. However, vaccination against PCV2 did not affect the PRRSV immunological responses (NAs and PRRSV-specific IFN-?-SCs), PRRSV viremia, PRRSV-induced lesions, or PRRSV antigens in the dually infected pigs. Vaccination against PRRSV did not induce immunological responses (PRRSV-specific IFN-?-SCs) or reduce PRRSV viremia, PRRSV-induced lesions, or PRRSV antigens in the dually infected pigs. In addition, vaccination against PRRSV increased PCV2 viremia, PCV2-induced lesions, and PCV2 antigens in the dually infected pigs. In summary, vaccination against PCV2 reduced PCV2 viremia, PCV2-induced lesions, and PCV2 antigens in the dually infected pigs. However, vaccination against PRRSV increased PCV2 viremia, PCV2-induced lesions, and PCV2 antigens in the dually infected pigs. Therefore, the PCV2 vaccine decreased the potentiation of PCV2-induced lesions by PRRSV in dually infected pigs. In contrast, the PRRSV vaccine alone did not decrease the potentiation of PCV2-induced lesions by PRRSV in dually infected pigs. PMID:23302743

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

2013-01-01

24

Epidemiology and transmission of porcine circovirus type 2 (PCV2).  

PubMed

PCV2 has been highly prevalent in the pig population for decades, prior to the emergence of associated clinical disease manifestations that severely affected the pig production worldwide in the late 90s. PCV2 can be further subdivided into several genotypes. From descriptive epidemiologic data, there is evidence of a global shift of the main PCV2 genotypes in different countries from PCV2a to PCV2b, which is generally associated with more severe disease. In addition, from analytic epidemiologic studies, the modified within-herd PCV2 dynamics of infection is strongly related to the increased incidence of clinical disorders associated with PCV2 infection. Because PCV2 is shed for a long time by an extremely large variety of routes, it easily spreads within the population both through horizontal and vertical transmission. Even if airborne transmission cannot be formally excluded, direct contact is certainly the most efficient infectious route due to the simultaneous exposure of susceptible pigs to contaminated respiratory, digestive, and urinary secretions since the probability of transmission is strongly limited by the distance between infectious and susceptible animals. Consequently, farm to farm transmission is restricted to the introduction of infected animals or infected animal products such as semen. More information would be required to assess the risk of other vehicles such as vaccines or feed ingredients since the probability of these products to be contaminated by PCV2 is unknown. However, owing to its transmission characteristics, PCV2 is able to be maintained within pig farms for years without any further need for re-introduction due to the population dynamics of modern pig operations, which continually renew the pool of the susceptible population through replacements and pig movements between compartments. PMID:22178804

Rose, Nicolas; Opriessnig, Tanja; Grasland, Béatrice; Jestin, André

2012-03-01

25

Building pressurization control with rooftop air conditioners  

SciTech Connect

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.

Winter, S.

1982-10-01

26

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

PubMed Central

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

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

2008-01-01

27

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

PubMed Central

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

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

2011-01-01

28

Controller modeling and evaluation for PCV electro-mechanical actuator  

NASA Technical Reports Server (NTRS)

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

Parker, Joey K.

1993-01-01

29

Shuttle Orbiter Atmospheric Revitalization Pressure Control Subsystem  

NASA Technical Reports Server (NTRS)

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.

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

1982-01-01

30

Characterisation of PCV2 isolates from Spain, Germany and France  

Microsoft Academic Search

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

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

2000-01-01

31

Ventilation Model  

SciTech Connect

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).

V. Chipman

2002-10-05

32

A role for preirradiation PCV chemotherapy for oligodendroglial brain tumors  

Microsoft Academic Search

Oligodendroglial tumors have been identified as a subgroup of glial neoplasms with a distinctly better response to chemotherapy\\u000a and overall survival than purely astrocytic gliomas. Here we report our experience with adjuvant postirradiation and preirradiation\\u000a chemotherapy using procarbazine, lomustine, and vincristine (PCV) in 27 patients with WHO grade II or III oligodendroglioma\\u000a or oligoastrocytoma. The efficacy of chemotherapy was assessed

Johannes Streffer; Martin Schabet; Michael Bamberg; Ernst H. Grote; Richard Meyermann; Karsten Voigt; Johannes Dichgans; Michael Weller

2000-01-01

33

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

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

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

2014-01-01

34

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

PubMed Central

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

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

2012-01-01

35

Neurotoxicity of combination chemotherapy with procarbazine, CCNU and vincristine (PCV) for recurrent glioma  

Microsoft Academic Search

In cerebral glioma combination chemotherapy with procabazine, CCNU and vincristine (PCV) is used as adjuvant therapy in cases of recurrence. Standard PCV is usually well tolerated, but intensive PCV (CCNU 130 mg\\/m2 on day 1, procarbazine 75 mg\\/m2 on day 8–21, vincristine 1.4 mg\\/m2 on day 8 and 29; 6 courses every 6 weeks) is less well tolerated. We observed

T. J. Postma; C. J. van Groeningen; R. J. G. M. Witjes; J. G. E. Weerts; J. H. Kralendonk; J. J. Heimans

1998-01-01

36

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

PubMed

Groups (5 to 15 per group) of gnotobiotic swine were infected oronasally with porcine circovirus type 2 (PCV2) at 3 days of age and then given 1 of 6 different commercial Mycoplasma hyopneumoniae (M. hyopneumoniae) bacterins as either a single dose (7 d of age, 1 application products) or 2 doses (7 and 21 d of age, 2 application product). Control groups received PCV2 alone (n = 9) or were infected with PCV2 and immunized twice with keyhole limpet hemocyanin (KLH) emulsified in incomplete Freund's adjuvant (ICFA) (n = 7). Five of 7 (71%) PCV2-infected piglets immunized with KLH/ICFA developed mild or overt PMWS, whereas none of 9 piglets infected with PCV2 alone developed PMWS. Five of 12 (42%) piglets vaccinated with a commercial bacterin containing mineral oil adjuvant developed PMWS following vaccination. None of the PCV2-infected piglets in the other bacterin-vaccinated groups developed PMWS in this model of PCV2-associated disease. This difference in prevalence of PMWS in piglets given the mineral oil-adjuvanted M. hyopneumoniae bacterin and the other M. hyopneumoniae bacterin vaccination groups was statistically significant (P < 0.05). PMID:17824156

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

2007-07-01

37

Ventilation shaft to increase effectiveness of natural ventilation.  

E-print Network

??Ventilation shafts can aid natural ventilation in buildings. Natural ventilation provides ventilation for occupants that can provide thermal comfort conditions. This study attempts to increase… (more)

Nagory, Abhay

2012-01-01

38

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

PubMed

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

Baró, J; Segalés, J; Martínez, J

2015-03-23

39

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...

40

COMPARISON OF CYTOKINE PROFILES IN PIGS SINGULARLY OR COINFECTED WITH PCV2, OR MYCOPLASMA HYOPNEUMONIAE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objectives of this study were to determine immune gene expression profiles in tracheobronchial lymph nodes (TBLN) following experimental infection with Porcine circovirus type 2 (PCV2), Mycoplasma hyopneumoniae, and PCV2/M. hyopneumoniae coinfection and compare the profiles to those of uninfecte...

41

Ventilator-driven xenon ventilation studies  

SciTech Connect

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

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

1984-07-01

42

112. REFRIGERANT CONDENSER TANKS AND PRESSURE CONTROLS IN NORTHEAST CORNER ...  

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

112. REFRIGERANT CONDENSER TANKS AND PRESSURE CONTROLS IN NORTHEAST CORNER OF MECHANICAL EQUIPMENT ROOM (201), LSB (BLDG. 751) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

43

The effect of mechanical ventilator settings during ventilator hyperinflation techniques: a bench-top analysis.  

PubMed

Ventilator hyperinflations are used by physiotherapists for the purpose of airway clearance in intensive care. There is limited data to guide the selection of mechanical ventilator modes and settings that may achieve desired flow patterns for ventilator hyperinflation. A mechanical ventilator was connected to two lung simulators and a respiratory mechanics monitor. Peak inspiratory (PIFR) and expiratory flow rates (PEFR) were measured during manipulation of ventilator modes (pressure support ventilation [PSV], volume-controlled synchronised intermittent mandatory ventilation [VC-SIMV] and pressure-controlled synchronised intermittent mandatory ventilation [PC-SIMV]) and ventilator settings (including set tidal volume, positive end-expiratory pressure, inspiratory flow rate, inspiratory pause, pressure support, inspiratory time and/or inflation pressure). Additionally, each trial was conducted with high (0.05 l/cmH2O) and low (0.01 l/cmH2O) compliance settings on the lung simulators. Each trial was dichotomised into success or failure under three categories (attainment of PIFR-PEFR less than or equal to 0.9, PEFR/PIFR greater than 17 l/min, PEFR greater than or equal to 40 l/min). A total of 232 trials were conducted (96 VC-SIMV, 96 PC-SIMV, 40 PSV). A greater proportion of VC-SIMV trials were ceased due to high peak inspiratory pressures (35%). However, VC-SIMV trials were more likely to be successful at meeting all three outcome measures (26 VC-SIMV trials, 7 PC-SIMV trials, 0 PSV trials). It was found that manipulation of settings in VC-SIMV mode appears more successful than PSV and PC-SIMV for ventilator hyperinflations. PMID:25579293

Thomas, P J

2015-01-01

44

Mechanical ventilator - infants  

MedlinePLUS

Ventilator - infants; Respirator - infants ... WHY IS A MECHANICAL VENTILATOR USED? A ventilator is used to provide breathing support for ill or immature babies. Sick or premature babies are often ...

45

Crankcase ventilator  

SciTech Connect

This patent describes a crankcase ventilator. It comprises: a conduct adapted to be attached to crankcase and a suction means for drawing air containing vapors from the crankcase through the conduit, a temperature sensitive element adapted to be placed in thermal contact with the crankcase, means for continuously varying the rate at which the suction means draws the air containing vapors from the crankcase according to temperature, and means connecting the varying means to the temperature sensitive element for causing the suction means to draw a greater volume of air from the crankcase when the crankcase is hot than when the crankcase is cold.

Pickering, J.J.

1989-11-14

46

Automated patient-ventilator interaction analysis during neurally adjusted non-invasive ventilation and pressure support ventilation in chronic obstructive pulmonary disease.  

PubMed

IntroductionDelivering synchronous assist during non-invasive ventilation (NIV) is challenging with flow or pressure controlled ventilators, especially in patients with chronic obstructive pulmonary disease (COPD). Neurally adjusted ventilatory assist (NAVA) uses diaphragm electrical activity (EAdi) to control the ventilator. We evaluated patient-ventilator interaction in patients with COPD during NIV with pressure support ventilation (PSV) and NAVA using a recently introduced automated analysis.MethodsTwelve COPD patients underwent three 30-minute trials: 1) PSV with dedicated NIV ventilator (NIV-PSVVision), 2) PSV with intensive care unit (ICU) ventilator (NIV-PSVServo-I), and 3) with NIV-NAVA. EAdi, flow, and airway pressure were recorded. Patient-ventilator interaction was evaluated by comparing airway pressure and EAdi waveforms with automated computer algorithms. The NeuroSync index was calculated as the percentage of timing errors between airway pressure and EAdi.ResultsThe NeuroSync index was higher (larger error) for NIV-PSVVision (24 [IQR 15-30] %) and NIV-PSVServo-I (21 [IQR 15-26] %) compared to NIV-NAVA (5 [IQR 4-7] %; P <0.001). Wasted efforts, trigger delays and cycling-off errors were less with NAVA (P <0.05 for all). The NeuroSync index and the number of wasted efforts were strongly correlated (r2¿=¿0.84), with a drastic increase in wasted efforts after timing errors reach 20%.ConclusionsIn COPD patients, non-invasive NAVA improves patient-ventilator interaction compared to PSV, delivered either by a dedicated or ICU ventilator. The automated analysis of patient-ventilator interaction allowed for an objective detection of patient-ventilator interaction during NIV. In addition, we found that progressive mismatch between neural effort and pneumatic timing is associated with wasted efforts. PMID:25307894

Doorduin, Jonne; Sinderby, Christer A; Beck, Jennifer; van der Hoeven, Johannes G; Heunks, Leo

2014-10-13

47

The effects of poor ventilation, low temperatures, type of feed and sex of bird on the development of ascites in broilers. physiopathological factors  

Microsoft Academic Search

The effects of type of feed, ambient temperature and ventilation were investigated on a fast?growing strain of broiler under conditions conducive to the induction of the ascites syndrome. Parameters used to monitor the syndrome were the erythrocyte packed cell volume (PCV), and the ascites heart index (AHI) which is a measure of the hypertrophy of the right ventricle; both these

A. Shlosberg; I. Zadikov; U. Bendheim; V. Handji; E. Berman

1992-01-01

48

Ventilator-driven xenon ventilation studies  

SciTech Connect

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

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

1984-07-01

49

Evidence for different patterns of natural inter-genotype recombination between two PCV2 parental strains in the field.  

PubMed

Co-infection with different virus strains is a precondition for genome recombination, which give rise to continuous evolution of porcine circovirus type 2 (PCV2). In the present study, 32 PCV2 positive clinical samples from the diseased and dead pigs were identified by classic PCR. 15 of 32 (46.8%) clinical samples were identified as infection with both PCV2a and PCV2b using genotype-specific PCR. 13/15 of PCV2 strains were identified as recombinants using sequencing analysis, phylogenetic analysis, recombination detection program and base-by-base comparison. Further analyses of the full-length sequences of these strains suggest that the natural recombination events occurred between strains DQ104423 (PCV2a) and AY579893 (PCV2b), yield two new recombinant clusters through different recombination patterns with crossover regions located in ORF2. Recombinant cluster 1 included 3 strains, and recombinant cluster 2 included 10 strains. These results demonstrate that recombination between PCV2a and PCV2b strains can occur in cap protein coding region through different patterns and yield different recombinants. Our study not only provided new evidences that PCV2 strains can undergo recombination through a variety of patterns, but also suggests that recombination events easily occur in the co-existence of different strains of PCV2. PMID:23545543

Huang, Yong; Shao, Meng; Xu, Xingang; Zhang, Xiujuan; Du, Qian; Zhao, Xiaomin; Zhang, Wenlong; Lyu, Yahui; Tong, Dewen

2013-07-01

50

A system for high-frequency oscillatory ventilation and intermittent mandatory ventilation in neonates.  

PubMed

We combined high-frequency oscillatory ventilation and intermittent mandatory ventilation, using a system composed of an Emerson airway vibrator, a Babybird 1 ventilator, and rate/pressure monitors. The Emerson device, a modified air compressor with rate controller, oscillated a small volume of gas at the airway. This device was coupled to the bird unit through a circuit of our design. Humidified fresh gas and pressure-relief valves were provided by the bird ventilator, and mean airway pressure was adjusted by its expiratory-limb venturi device or by the end-expiratory pressure control. The volume of gas delivered by the oscillator to various sites was measured with a plethysmograph tuned to high frequencies. At frequencies of 20 to 30 Hz, a 27-ml volume from the oscillator decreased to between 7 and 14 ml at the proximal airway, and to between 0.1 and 2.3 ml at the distal tip of the endotracheal tube. The magnitude of this decrease depended on the size of the endotracheal tube, the circuit resistance of the ventilator, oscillation frequency, and the position of the oscillator's expansion-chamber valve. We have used this system for over 3 yr to ventilate sick neonates safely and effectively. PMID:3459633

Kopotic, R J; Mannino, F L; Boynton, B R

1986-07-01

51

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

52

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

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

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

2014-01-01

53

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

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

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

54

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

PubMed Central

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.

Papatsiros, Vassilis

2012-01-01

55

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

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

56

VENTILATION MODEL REPORT  

SciTech Connect

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.

V. Chipman

2002-10-31

57

Home Ventilator Guide  

MedlinePLUS

... is ventilation? respiration? Ventilation is the process of moving air in and out of the lungs. Respiration ... when I'm talking and using the vent. Moving about in bed does not cause alarms as ...

58

Pressure Controlled Heat Pipe for Precise Temperature Control  

Microsoft Academic Search

This paper discusses the design and test of a pressure controlled heat pipe (PCHP) for spacecraft thermal management. The PCHP combines a conventional grooved aluminum-ammonia heat pipe with a variable-volume non-condensable gas reservoir to create a heat pipe whose conductance can be precisely controlled. Testing showed that a prototype PCHP was capable of maintaining a stable evaporator temperature within 0.1

David B. Sarraf; Sanjida Tamanna; Peter M. Dussinger

2008-01-01

59

DEMAND CONTROLLED VENTILATION AND CLASSROOM VENTILATION  

SciTech Connect

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.

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

2014-01-06

60

Genetic variation of porcine circovirus type 2 (PCV2) and its relevance to vaccination, pathogenesis and diagnosis.  

PubMed

Porcine circovirus-associated disease (PCVAD) encompasses a group of complex, multi-factorial syndromes, which are dependent on infection with porcine circovirus type 2 (PCV2). Current strains of PCV2 circulating in the field are classified into two groups, termed PCV2a and PCV2b. Outbreaks of severe PCVAD in North America and other countries are often linked to a shift from PCV2a to PCV2b as the predominant genotype. Therefore, genotype-specific differences in pathogenesis and antigenicity have been suggested. Overall, evidence suggests that virulence is a function of the specific PCV2 isolate, regardless of genotype. In addition, only minor antigenic differences have been reported. In terms of immunopathogenesis, a conserved decoy epitope, located in the C-terminal region of the capsid protein, provides an explanation for the inability to identify pathogenic differences between genotypes. Finally, genetic variation in PCV2 and the resulting consequences with respect to vaccination and diagnostics are discussed. PMID:22198217

Trible, Benjamin R; Rowland, Raymond R R

2012-03-01

61

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

PubMed

The aim of this article is to develop a knowledge-based therapy for management of rats with respiratory distress. A mechanical ventilator was designed to achieve this aim. The designed ventilator is called an intelligent mechanical ventilator since fuzzy logic was used to control the pneumatic equipment according to the rat's status. LabVIEW software was used to control all equipments in the ventilator prototype and to monitor respiratory variables in the experiment. The designed ventilator can be controlled both manually and by fuzzy logic. Eight female Wistar-Albino rats were used to test the designed ventilator and to show the effectiveness of fuzzy control over manual control on pressure control ventilation mode. The anesthetized rats were first ventilated for 20 min manually. After that time, they were ventilated for 20 min by fuzzy logic. Student's t-test for p?ventilator and developed knowledge-based therapy support artificial respiration of living things successfully. PMID:25205667

Guler, Hasan; Ata, Fikret

2014-09-01

62

Differential-pressure control device for a fuel cell  

SciTech Connect

A differential-pressure control device for fuel cell comprises three liquid tubs allowed to communicate with each other at their respective bottom portions through a sealing liquid having free surfaces, gas pipe means which connect the liquid tubs to gas outlets of the fuel cell respectively to introduce the gas flows from an anode, a cathode and a cell container of the fuel cell into the sealing liquid of the liquid tubs, each of the gas pipe means being formed with gas blow out section opened in the sealing liquid at the end portion thereof, the gas blow out sections having relative heights set at the value corresponding to predetermined differential pressure among the electrodes and the cell container, and gas conduit means for guiding the gas to the outside of the device from the gas chambers defined by the liquid tubs and the free surfaces of the sealing liquid respectively and located at the tops of the liquid tubs respectively. The differential-pressure control device has no mechanical movable part and makes it possible to always keep the differential pressure at a constant and, at the same time, to absorb the transient small variations in pressure of the electrodes.

Yamaguchi, M.; Maruko, S.; Nogita, S.; Shimada, K.; Tsutsumi, Y.

1985-07-09

63

Hydraulic pressure control apparatus for a continuously variable transmission  

SciTech Connect

This patent describes a hydraulic pressure control apparatus for a continuously variable transmission. The transmission includes a driving pulley having a fixed member and a movable member. The movable member is actuated by a hydraulic cylinder to form a V-shaped opening between the movable member and the fixed member. A driven pulley has another fixed member and another movable member. The another movable member is similarly actuated by another hydraulic cylinder to form a similar V-shaped opening between the another movable member and the another fixed member. A belt member spans the driving and driven pulleys such that an effective diameter of the driving and driven pulleys can be varied with respect to each other to obtain different speed ratios. The hydraulic pressure control apparatus comprises: a first presssure detecting means in communication with the hydraulic cylinder of the driving pulley for detecting a pressure of the hydraulic cylinder of the driving pulleys, the first pressure detecting means outputting a first pressure signal having a first value; and a second pressure detecting means in communication with another hydraulic cylinder of the driven pulley for detecting the pressure of the another hydraulic cylinder of the driven pulley, the second pressure detecting means outputting a second pressure signal having a second value.

Shigematsu, T.; Watanabe, T.

1986-10-28

64

Porcine circovirus type 2 (PCV2)-infection and re-inoculation with homologous or heterologous strains: virological, serological, pathological and clinical effects in growing pigs  

PubMed Central

Long-term PCV2 infection and/or concurrent infection with genotypes PCV2a and PCV2b may play a role in the development of clinical porcine circovirus-associated disease (PCVAD). To evaluate this premise, 24 11-week-old specific pathogen-free (SPF) pigs were randomly assigned to 1 of 4 treatments: negative controls, a single inoculation with PCV2a, single inoculation followed by re-inoculation with a homologous PCV2a strain, or repeated inoculations with heterologous strains (PCV2a, PCV2b). Pigs were evaluated for clinical signs daily through 140 days post inoculation (dpi). Serum samples were collected every other day from dpi 0 through 14 and weekly thereafter. PCV2-inoculated pigs were viremic by dpi 2 and 13 of 18 pigs remained viremic at 140 dpi. No statistical differences in the onset, level, or duration of PCV2 viremia were detected among treatment groups. Anti-PCV2 antibodies were detected between 14 and 28 dpi and were present through 140 dpi without statistical differences in antibody response among treatment groups. In the current study, pigs had extended viremia combined with detectable tissue PCV2 antigen levels despite the presence of high levels of anti-PCV2 antibody; however, no clinical disease was observed. PMID:20167193

Opriessnig, Tanja; Prickett, John R.; Madson, Darin M.; Shen, Hui-Gang; Juhan, Nicole M.; Pogranichniy, Roman M.; Meng, Xiang-Jin; Halbur, Patrick G.

2010-01-01

65

Protective garment ventilation system  

NASA Technical Reports Server (NTRS)

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.

Lang, R. (inventor)

1970-01-01

66

GENERAL VIEW SHOWING VENTILATOR NUMBER NINE. THIS VENTILATOR IS SLIGHTLY ...  

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

GENERAL VIEW SHOWING VENTILATOR NUMBER NINE. THIS VENTILATOR IS SLIGHTLY MORE ORNATE THAN WAS GENERALLY USED BECAUSE OF ITS LOCATION - Old Croton Aqueduct, Ventilator Number 9, Spring & Everett Streets, Ossining, Westchester County, NY

67

1. GENERAL VIEW SHOWING VENTILATOR NO. 9. THIS VENTILATOR IS ...  

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

1. GENERAL VIEW SHOWING VENTILATOR NO. 9. THIS VENTILATOR IS SLIGHTLY MORE ORNATE THAN WAS GENERALLY USED BECAUSE OF ITS LOCATION. - Old Croton Aqueduct, Ventilator Number 9, Spring & Everett Streets, Ossining, Westchester County, NY

68

Noninvasive ventilation in trauma  

PubMed Central

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

Karcz, Marcin K; Papadakos, Peter J

2015-01-01

69

Noninvasive ventilation in trauma.  

PubMed

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

Karcz, Marcin K; Papadakos, Peter J

2015-02-01

70

Ventilator for ignition distributor  

SciTech Connect

A ventilator for an ignition distributor is described in which bent air holes are provided in a housing of the distributor, and ventilation of the distributor is performed by utilizing rotation of air in the distributor caused by rotation of a distribution rotor. The improvement is that the angle of bend of each bent air hole is an obtuse angle and among the air holes, a cross-sectional area of a each ventilation intake port is larger than that of each ventilation exhaust port.

Arano, I.; Kokubun, T.

1988-12-27

71

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

72

Ventilator Associated Pneumonia (VAP)  

E-print Network

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

Connor, Ed

73

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

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

2014-01-01

74

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

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

Ferrari, Luca; Borghetti, Paolo; De Angelis, Elena; Martelli, Paolo

2014-01-01

75

Tank Pressure Control Experiment: Thermal Phenomena in Microgravity  

NASA Technical Reports Server (NTRS)

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

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

1996-01-01

76

Ventilating Air-Conditioner  

NASA Technical Reports Server (NTRS)

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.

Dinh, Khanh

1994-01-01

77

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

PubMed

For specific surgical interventions, such as aortic stent implantation, it might be temporarily necessary to decrease mean arterial pressure to rather low levels (around 40 mm Hg). Such hypotensive pressure levels are necessary to avoid intra- and postoperative intricacies. Traditionally, the drug Nitroprussidnatrium is used for this task. To adjust the correct amount of drug to reach the target pressure as fast as possible and without overshoot, the anaesthetists typically use empirical knowledge and might need several minutes until the target point is reached. In our research group, an adaptive control system was developed for this task which is able to compute and set the transient drug release automatically. For the design and testing of the adaptive control strategy, the well known Guyton model was implemented into the MATLAB/Simulink development environment. This paper describes the implementation and adaption of the Guyton model to hypotensive pressure control and provides some algorithmic details of the adaptive control strategy for automatic drug delivery in deep hypotension. The designed control system was successfully validated in animal trials (25 trials on 7 pigs). Following this, an additional controller component for increase of blood pressure with the help of the drug Noradrenalin was implemented. It is now possible to increase blood pressure to a specific value to save defined cerebral perfusion pressure for patients with craniocerebral injury. In a second pilot trial, this controller extension was tested in 10 pigs. PMID:19807293

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

2009-10-01

78

Tank pressure control in low gravity by jet mixing  

NASA Technical Reports Server (NTRS)

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.

Bentz, Michael D.

1993-01-01

79

Pulley actuating hydraulic pressure control for continuously variable transmission  

SciTech Connect

A hydraulic pressure control system for a continuously variable transmission is described, comprising: a manual selector valve having a plurality of forward drive positions and being shiftable in a first direction from one or the other of two forward drive positions selected from the plurality of forward drive positions and in a second direction opposite to the first direction from the other to the one of the two forward drive positions selected; means for generating a pulley actuating hydraulic fluid pressure; means for hydraulically actuating the driver pulley and the follower pulley in response to the hydraulic fluid pressure in such a manner as to effect an upshifting in a reduction ratio between the driver and follower pulleys in response to the manual selector valve having been shifted in the first direction from the one to the other of the two forward drive positions selected; and control means for causing the hydraulic fluid pressure generating means to temporarily increase the level of the hydraulic fluid pressure whenever the manual selector valve is shifting in the first direction from the one to the other of the two forward drive positions selected.

Yamamuro, S.; Kumura, H.

1989-04-11

80

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

PubMed

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

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

2014-12-01

81

What Is a Ventilator?  

MedlinePLUS

... tor) is a machine that supports breathing. These machines mainly are used in hospitals. Ventilators: Get oxygen into the lungs. Remove carbon dioxide from the body. (Carbon dioxide is a waste gas that can ...

82

Why We Ventilate  

SciTech Connect

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.

Logue, Jennifer M.; Sherman, Max H.; Price, Phil N.; Singer, Brett C.

2011-09-01

83

Conventional mechanical ventilation.  

PubMed

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

Tobias, Joseph D

2010-05-01

84

Initial Effects of the National PCV7 Childhood Immunization Program on Adult Invasive Pneumococcal Disease in Israel  

PubMed Central

Background PCV7 was introduced as universal childhood vaccination in Israel in July 2009 and PCV13 in November 2010. Here we report data on adult invasive pneumococcal disease (IPD), two years post PCV7 implementation and before an expected effect of PCV13. Methods An ongoing nationwide active-surveillance (all 27 laboratories performing blood cultures in Israel), providing all blood & CSF S. pneumoniae isolates from persons >18 y was initiated in July 2009. Capture-recapture method assured reporting of >95% cases. All isolates were serotyped in one central laboratory. IPD outcome and medical history were recorded in 90%. Second year post PCV implementation is compared to the first year. Results During July 2009 to June 2011, 970 IPD cases were reported (annual incidence [/100,000] of 9.17 and 10.16 in the two consecutive years, respectively). Respective case fatality rates (CFRs) were 20% and 19.1%. Incidence of IPD and CFR increased with age and number of comorbidities. Incidence rate was significantly greater during the second winter, 7.79/100,000 vs. 6.14/100,000 in first winter, p?=?0.004, with a non-significant decrease during summer months (3.02 to 2.48/100,000). The proportion of IPD cases due to PCV7-serotypes decreased from 27.5% to 13.1% (first to second year) (p<0.001). Yet, non-PCV13-strains increased from 32.7% to 40.2% (p?=?0.017). The increase in non-PCV13-strains was highly significant in immunocompromised patients and to a lesser degree in non-immunocompromised at risk or in older patients (>64 y). Among younger/healthier patients serotype 5 was the major increasing serotype. Penicillin and ceftriaxone resistance decreased significantly in the second year. Conclusions While overall annual incidence of IPD did not change, the indirect effect of PCV7 vaccination was evident by the significant decrease in PCV7 serotypes across all age groups. Increase in non-VT13 strains was significant in immunocompromised patients. A longer follow-up is required to appreciate the full effect of infant vaccination on annual IPD. PMID:24516649

Regev-Yochay, Gili; Rahav, Galia; Riesenberg, Klaris; Wiener-Well, Yonit; Strahilevitz, Jacob; Stein, Michal; Glikman, Daniel; Weber, Gabriel; Potasman, Israel; Dagan, Ron

2014-01-01

85

Poor Long-Term Blood Pressure Control after Intracerebral Hemorrhage  

PubMed Central

Background and Purpose Hypertension is the most important risk factor associated with intracerebral hemorrhage (ICH). We explored racial differences in blood pressure (BP) control after ICH and assessed predictors of BP control at presentation, 30 days, and 1 year in a prospective cohort study. Methods Subjects with spontaneous ICH were identified from the DiffErenCes in the Imaging of Primary Hemorrhage based on Ethnicity or Race (DECIPHER) Project. Blood pressure was compared by race at each time point. Multivariable linear regression was used to determine predictors of presenting mean arterial pressure (MAP), and longitudinal linear regression was used to assess predictors of MAP at follow-up. Results A total of 162 patients were included (mean age 59, 53% male, 77% black). MAP at presentation was 9.6 mmHg higher in blacks than whites despite adjustment for confounders (p=0.065). Fewer than 20% of patients had normal blood pressure (<120/80 mmHg) at 30 days or 1 year. While there was no difference at 30 days (p=0.331), blacks were more likely than whites to have Stage I/II hypertension at one year (p=0.036). Factors associated with lower MAP at follow-up in multivariable analysis were being married at baseline (p=0.032) and living in a facility (versus personal residence) at the time of BP measurement (p=0.023). Conclusions Long-term blood pressure control is inadequate in patients following ICH, particularly in blacks. Further studies are needed to understand the role of social support and barriers to control to identify optimal approaches to improve blood pressure in this high-risk population. PMID:22903494

Zahuranec, Darin B.; Wing, Jeffrey J.; Edwards, Dorothy F.; Menon, Ravi S.; Fernandez, Stephen J.; Burgess, Richard E.; Sobotka, Ian A.; German, Laura; Trouth, Anna J.; Shara, Nawar M.; Gibbons, M. Chris; Boden-Albala, Bernadette; Kidwell, Chelsea S.

2012-01-01

86

Blood pressure control and components of the metabolic syndrome: the GOOD survey  

Microsoft Academic Search

BACKGROUND: The GOOD (Global Cardiometabolic Risk Profile in Patients with Hypertension Disease) survey showed that blood pressure control was significantly worse in hypertensive patients with metabolic syndrome and\\/or diabetes mellitus than in those with essential hypertension only. This analysis aimed to investigate which components of the metabolic syndrome are primarily associated with poor blood pressure control. METHODS: The GOOD survey

Walter Zidek; Lisa Naditch-Brûlé; Stefano Perlini; Csaba Farsang; Sverre E Kjeldsen

2009-01-01

87

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

PubMed

Porcine circovirus type 2 (PCV2) is a ubiquitous virus that mainly affects nursery and fattening pigs causing systemic disease (PCV2-SD) or subclinical infection. A characteristic sign in both presentations is reduction of average daily weight gain (ADWG). The present study aimed to assess the relationship between PCV2 load in serum and ADWG from 3 (weaning) to 21 weeks of age (slaughter) (ADWG 3-21). Thus, three different boar lines were used to inseminate sows from two PCV2-SD affected farms. One or two pigs per sow were selected (60, 61 and 51 piglets from Pietrain, Pietrain×Large White and Duroc×Large White boar lines, respectively). Pigs were bled at 3, 9, 15 and 21 weeks of age and weighted at 3 and 21 weeks. Area under the curve of the viral load at all sampling times (AUCqPCR 3-21) was calculated for each animal according to standard and real time quantitative PCR results; this variable was categorized as "negative or low" (<10(4.3) PCV2 genome copies/ml of serum), "medium" (?10(4.3) to ?10(5.3)) and "high" (>10(5.3)). Data regarding sex, PCV2 antibody titre at weaning and sow parity was also collected. A generalized linear model was performed, obtaining that paternal genetic line and AUCqPCR 3-21 were related to ADWG 3-21. ADWG 3-21 (mean±typical error) for "negative or low", "medium" and "high" AUCqPCR 3-21 was 672±9, 650±12 and 603±16g/day, respectively, showing significant differences among them. This study describes different ADWG performances in 3 pig populations that suffered from different degrees of PCV2 viraemia. PMID:25448444

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

2014-12-01

88

Ventilator associated pneumonia  

PubMed Central

Hospital acquired or nosocomial infections continue to be an important cause of morbidity and mortality. The critically ill patient is at particular risk of developing intensive care unit acquired infection, with the lungs being especially vulnerable. Nosocomial bacterial pneumonia occurring after two days of mechanical ventilation is referred to as ventilator associated pneumonia, and is the most common nosocomial infection seen in the intensive care unit. Intubation of the trachea and mechanical ventilation is associated with a 7?fold to 21?fold increase in the incidence of pneumonia and up to 28% of patients receiving mechanical ventilation will develop this complication. Its development is associated with an attributable increase in morbidity and mortality. The establishment of an accurate diagnosis of ventilator associated pneumonia remains problematic and as yet there is still no accepted “gold standard” for diagnosis. The responsible pathogens vary according to case mix, local resistance patterns, and methodology of sampling. However, there is general agreement that rapid initiation of appropriate antimicrobial therapy improves outcome. PMID:16517798

Hunter, J D

2006-01-01

89

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

PubMed Central

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

2014-01-01

90

A knowledge- and model-based system for automated weaning from mechanical ventilation: technical description and first clinical application.  

PubMed

To describe the principles and the first clinical application of a novel prototype automated weaning system called Evita Weaning System (EWS). EWS allows an automated control of all ventilator settings in pressure controlled and pressure support mode with the aim of decreasing the respiratory load of mechanical ventilation. Respiratory load takes inspired fraction of oxygen, positive end-expiratory pressure, pressure amplitude and spontaneous breathing activity into account. Spontaneous breathing activity is assessed by the number of controlled breaths needed to maintain a predefined respiratory rate. EWS was implemented as a knowledge- and model-based system that autonomously and remotely controlled a mechanical ventilator (Evita 4, Dräger Medical, Lübeck, Germany). In a selected case study (n = 19 patients), ventilator settings chosen by the responsible physician were compared with the settings 10 min after the start of EWS and at the end of the study session. Neither unsafe ventilator settings nor failure of the system occurred. All patients were successfully transferred from controlled ventilation to assisted spontaneous breathing in a mean time of 37 ± 17 min (± SD). Early settings applied by the EWS did not significantly differ from the initial settings, except for the fraction of oxygen in inspired gas. During the later course, EWS significantly modified most of the ventilator settings and reduced the imposed respiratory load. A novel prototype automated weaning system was successfully developed. The first clinical application of EWS revealed that its operation was stable, safe ventilator settings were defined and the respiratory load of mechanical ventilation was decreased. PMID:23892513

Schädler, Dirk; Mersmann, Stefan; Frerichs, Inéz; Elke, Gunnar; Semmel-Griebeler, Thomas; Noll, Oliver; Pulletz, Sven; Zick, Günther; David, Matthias; Heinrichs, Wolfgang; Scholz, Jens; Weiler, Norbert

2014-10-01

91

Natural ventilation generates building form  

E-print Network

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 ...

Chen, Shaw-Bing

1996-01-01

92

Innovative Energy Efficient Industrial Ventilation  

E-print Network

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...

Litomisky, A.

2005-01-01

93

Ventilation flow: Submerged  

NASA Technical Reports Server (NTRS)

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.

Hutchinson, D.

1985-01-01

94

A review on wind driven ventilation techniques  

Microsoft Academic Search

Natural ventilation has gained prominence in recent times as a bespoke method of ventilating buildings. The two fundamental principles of natural ventilation are stack effect and wind driven ventilation. This paper reviews miscellaneous wind driven ventilation designs with respect to traditional means such as wind towers and more modern techniques including turbine ventilators and wind catchers. A distinction is made

Naghman Khan; Yuehong Su; Saffa B. Riffat

2008-01-01

95

3, 805826, 2006 Ventilation under  

E-print Network

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

Paris-Sud XI, Université de

96

The International Journal of Ventilation  

E-print Network

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

California at Davis, University of

97

Possible pathogenic interplay between Chlamydia suis, Chlamydophila abortus and PCV-2 on a pig production farm.  

PubMed

A concurrent outbreak of chlamydial disease in boars, sows and gilts and postweaning multisystemic wasting syndrome (PMWS) in weaned piglets was investigated on a large pig production farm in Estonia. Chlamydia suis DNA was detected in conjunctival swabs from boars, sows and gilts, but also in the faeces of boars and sows. Chlamydophila abortus DNA was found in semen, and in conjunctival swabs from sows; DNA was demonstrated by microarrays. Serum samples from boars were examined using a Chlamydiaceae-specific recombinant ELISA. All 10 serum samples examined were positive (1:960 to 1:3840). Chlamydiosis was characterised by reproductive failure and conjunctivitis. Piglets were not examined for Chlamydiaceae, as eye problems were not observed. Piglets showed wasting, respiratory signs, diarrhoea, enlargement of lymph nodes and increased mortality (10 per cent). Porcine circovirus type 2 (PCV-2) was detected in the lymph nodes of piglets by immunohistochemistry, and PCV-2 antibodies were demonstrated in all 10 serum samples from sows examined using an immunoperoxidase monolayer assay. PMID:20228367

Schautteet, K; Beeckman, D S A; Delava, P; Vanrompay, D

2010-03-13

98

Space station ventilation study  

NASA Technical Reports Server (NTRS)

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.

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

1972-01-01

99

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 ...

100

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

PubMed Central

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

Bosworth, Hayden B.; Oddone, Eugene Z.

2002-01-01

101

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

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…

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

102

Design of characteristics of air-pressure-controlled hydraulic shock absorbers in an intercity bus  

Microsoft Academic Search

The air-pressure-controlled shock absorber is capable of changing its damping force depending on the air pressure in the air\\u000a springs. Due to the possibility of improving dynamic properties of all vehicles that use the axles’ air suspensions, BRANO\\u000a Inc. (the Czech producer of shock absorbers) started to develop semi-active air-pressure-controlled hydraulic telescopic shock\\u000a absorbers. The SOR C 12 intercity bus

Pavel Polach; Michal Hajžman

2008-01-01

103

Noisy Ventilation Improves Lung Function  

NASA Astrophysics Data System (ADS)

It has been shown that mechanical ventilation in the setting of acute lung injury may propagate additional injury within the lung and numerous studies have been carried out to determine the optimal method of minimizing ventilator induced lung injury while still maintaining life-sustaining gas exchange. We have found that noise added to tidal volume and frequency, called noisy ventilation, during mechanical ventilation improves both lung mechanics and oxygenation in a rodent model of acute lung injury. Additionally, the standard deviation of the noise appears to be directly related to the magnitude of improvements seen with this ventilation modality in a manner similar to stochastic resonance. Furthermore, healthy guinea pigs that underwent with noisy ventilation exhibited increased surfactant content and reduced plasma proteins than their conventionally ventilated counterparts within the alveolar space of the lung. This suggests that not only did noisy ventilation induce endogenous surfactant release, but also served to reduce ventilator induced lung injury in this animal model. In conclusion, noisy ventilation improves blood oxygenation during acute lung injury and also serves to enhance lung function and reduce ventilator induced lung injury in healthy lungs.

Suki, Béla; Arold, Stephen P.; Alencar, Adriano; Lutchen, Kenneth R.; Ingenito, Edward P.

2003-05-01

104

ASHRAE and residential ventilation  

SciTech Connect

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.

Sherman, Max H.

2003-10-01

105

Insulated heat activated ventilator  

SciTech Connect

A building construction is described comprising a building structure and a ventilator, the ventilator including a stack defining a passage having an inlet and an outlet communicating with one another, a closure operative to normally seal the passage, insulating material supported by the closure and providing an air seal within the passage under normal conditions, and normally inoperative vent actuating means associated with the closure, the vent actuating means being operative in response to the presence of combustion products for disabling the closure, the closure and the insulating material being automatically released from the passage of the stack upon disablement of the closure whereby the combustion products are exhausted through the passage of the stack to atmosphere.

Kelly, T.L.

1993-05-25

106

Investigation on tunnel fire phenomenon under different emergency ventilation systems.  

E-print Network

???In this research study, the ventilating effect on tunnel fire development has been investigated under 4 ventilation mode throughout the tunnel: natural ventilation, fully-transverse ventilation,… (more)

Se, Mei King (???)

2009-01-01

107

Prospective Evaluation of Subretinal Vessel Location in Polypoidal Choroidal Vasculopathy (PCV) and Response of Hemorrhagic and Exudative PCV to High-Dose Antiangiogenic Therapy (An American Ophthalmological Society Thesis)  

PubMed Central

Purpose: The purpose of this study was to determine the following: (1) Is polypoidal choroidal vasculopathy (PCV) a subretinal neovascular process, rather than a choroidal vascular anomaly? and (2) Is a higher dose of ranibizumab (2.0 mg/0.05 mL) more effective in treating PCV than the current dose (0.5 mg/0.05 mL) approved for treatment of age-related macular degeneration? Methods: Retrospective evaluation of PCV in 104 eyes of 86 patients was accomplished with use of indocyanine green angiography plus optical coherence tomography to localize the branching vascular network and the polyps. Nineteen eyes of 19 patients with active leaking and exudation underwent a prospective open-label trial of monthly high-dose intravitreal ranibizumab (2.0 mg/0.05 mL). The primary outcome was prevention of major vision loss (?15 ETDRS letters). Secondary outcomes included adverse events, improved vision, and changes in subretinal hemorrhage, subretinal fluid, macular edema, and polypoidal complexes at 6 months. Results: The PCV vessels were localized beneath the retinal pigment epithelium (RPE) and above Bruch’s membrane in 103 (99%) of 104 eyes. In the high-dose ranibizumab trial at 6 months, none of the patients lost ?15 letters in visual acuity, and 5 (26%) of 19 gained ?15 letters. Decreases were noted in subretinal fluid in 14 (82%) of 17 eyes, subretinal hemorrhage in 12 (100%) of 12, RPE detachment in 14 (88%) of 16, macular edema in 11 (92%) of 12, and polyps in 15 (79%) of 19 eyes. Conclusions: PCV vessels are a subtype of subretinal neovascularization located above Bruch’s membrane and below RPE. High-dose ranibizumab (2.0 mg/0.05 mL) decreased exudation and hemorrhage and resulted in significant polyp regression, although branching vascular networks persisted.

Kokame, Gregg T.

2014-01-01

108

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...

109

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

E-print Network

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

Boyer, Edmond

110

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

PubMed

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

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

2014-09-01

111

Pretest Predictions for Ventilation Tests  

SciTech Connect

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.

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

2007-01-17

112

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

E-print Network

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

Farritor, Shane

113

Ventilator management protocols in pediatrics.  

PubMed

Management of mechanical ventilation is a complex process with outcomes affected by multiple patient and caregiver variable. Well-constructed protocols represent the synthesis of best available evidence regarding ventilator management. In adults, protocols improve important outcomes such as duration of mechanical ventilation, length of stay, and complication rates; however, protocols are not uniformly successful. In pediatrics, the available evidence does not suggest that ventilator management protocols should be adopted routinely, which may be due to pediatric-specific attributes such as a generally shorter weaning duration. Evidence suggests support for protocols to carefully titrate sedation. In addition, daily assessment of SBTs improves patient outcomes and should be more uniformly adopted in pediatrics. Ventilator-related outcomes may be affected by other confounding factors such as nutrition and fluid balance. Specific subpopulations, such as children who have congenital heart disease, may present opportunities for focused use of ventilator management protocols. Protocolized ventilation has an important place in trials of new therapeutic strategies such as surfactant or proning. It is hoped that future research will further define the appropriate use of protocols in the general PICU population. Although specific protocols cannot be routinely recommended, a multidisciplinary team approach to synthesizing available literature and determining best practice is a useful model. This approach will foster "team ownership" of ventilator management by all involved, thus engendering the best possible outcomes for critically ill children who require mechanical ventilation. PMID:16952800

Graham, Alan S; Kirby, Aileen L

2006-09-01

114

[Prevalence and association of porcine circovirus type 2 (PCV2), porcine parvovirus (PPV) and porcine reproductive and respiratory syndrome virus (PRRSV) in aborted fetuses, mummified fetuses, stillborn and nonviable neonatal piglets].  

PubMed

Porcine circovirus type 2 (PCV2) seems to cause reproductive failure in sows not only in experimental studies. A retrospective study was made with a total of 252 aborted fetuses, mummified fetuses, stillborn and nonviable neonatal piglets to determine the presence of PCV2, porcine parvovirus (PPV) and porcine respiratory and reproductive syndrome virus (PRRSV) by PCR. PCV2 was found in all stages of gestation in 27.1 percent of samples examined. A statistically significant association could be shown between the detection of PCV2 and PRRSV. However, no significant association was seen between the detection of PCV2 and PPV and between PPV and PRRSV. PMID:16240914

Ritzmann, M; Wilhelm, S; Zimmermann, P; Etschmann, B; Bogner, K H; Selbitz, H J; Heinritzi, K; Truyen, U

2005-09-01

115

46 CFR 116.610 - Ventilation ducts.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Ventilation ducts. 116.610 Section 116.610 Shipping COAST GUARD, DEPARTMENT OF HOMELAND...PASSENGERS CONSTRUCTION AND ARRANGEMENT Ventilation § 116.610 Ventilation ducts. (a) For the...

2010-10-01

116

46 CFR 194.20-5 - Ventilation.  

Code of Federal Regulations, 2012 CFR

...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...

2012-10-01

117

46 CFR 194.20-5 - Ventilation.  

Code of Federal Regulations, 2010 CFR

...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...

2010-10-01

118

24 CFR 3285.505 - Crawlspace ventilation.  

Code of Federal Regulations, 2010 CFR

...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...

2010-04-01

119

24 CFR 3285.505 - Crawlspace ventilation.  

...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...

2014-04-01

120

24 CFR 3285.505 - Crawlspace ventilation.  

Code of Federal Regulations, 2013 CFR

...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...

2013-04-01

121

24 CFR 3285.505 - Crawlspace ventilation.  

Code of Federal Regulations, 2012 CFR

...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...

2012-04-01

122

24 CFR 3285.505 - Crawlspace ventilation.  

Code of Federal Regulations, 2011 CFR

...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...

2011-04-01

123

46 CFR 194.20-5 - Ventilation.  

Code of Federal Regulations, 2011 CFR

...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...

2011-10-01

124

46 CFR 194.20-5 - Ventilation.  

Code of Federal Regulations, 2013 CFR

...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...

2013-10-01

125

Laboratory and Industrial Ventilation  

NASA Technical Reports Server (NTRS)

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.

1972-01-01

126

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

NASA Astrophysics Data System (ADS)

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.

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

2012-05-01

127

Subsurface Ventilation System Description Document  

Microsoft Academic Search

The Subsurface Ventilation System supports the construction and operation of the subsurface repository by providing air for personnel and equipment and temperature control for the underground areas. Although the system is located underground, some equipment and features may be housed or located above ground. The system ventilates the underground by providing ambient air from the surface throughout the subsurface development

Eric Loros

2001-01-01

128

Lung Ventilation/Perfusion Scan  

MedlinePLUS

... from the NHLBI on Twitter. What Is a Lung Ventilation/Perfusion Scan? A lung ventilation/perfusion scan, or VQ scan, is a ... that measures air and blood flow in your lungs. A VQ scan most often is used to ...

129

Transpired Air Collectors - Ventilation Preheating  

SciTech Connect

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.

Christensen, C.

2006-06-22

130

Mechanical ventilation in abdominal surgery.  

PubMed

One of the key challenges in perioperative care is to reduce postoperative morbidity and mortality. Patients who develop postoperative morbidity but survive to leave hospital have often reduced functional independence and long-term survival. Mechanical ventilation provides a specific example that may help us to shift thinking from treatment to prevention of postoperative complications. Mechanical ventilation in patients undergoing surgery has long been considered only as a modality to ensure gas exchange while allowing maintenance of anesthesia with delivery of inhaled anesthetics. Evidence is accumulating, however, suggesting an association between intraoperative mechanical ventilation strategy and postoperative pulmonary function and clinical outcome in patients undergoing abdominal surgery. Non-protective ventilator settings, especially high tidal volume (VT) (>10-12mL/kg) and the use of very low level of positive end-expiratory pressure (PEEP) (PEEP<5cmH2O) or no PEEP, may cause alveolar overdistension and repetitive tidal recruitment leading to ventilator-associated lung injury in patients with healthy lungs. Stimulated by previous findings in patients with acute respiratory distress syndrome, the use of lower tidal volume ventilation is becoming increasingly more common in the operating room. However, lowering tidal volume, though important, is only part of the overall multifaceted approach of lung protective mechanical ventilation. In this review, we aimed at providing the most recent and relevant clinical evidence regarding the use of mechanical ventilation in patients undergoing abdominal surgery. PMID:25153670

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

2014-01-01

131

New Ventilated Isolation Cage  

PubMed Central

A multifunction lid has been developed for a commercially available transparent animal cage which permits feeding, watering, viewing, long-term holding, and local transport of laboratory rodents on experiment while isolating the surrounding environment. The cage is airtight except for its inlet and exhaust high-efficiency particulate air filters, and it is completely steam-sterilizable. Opening of the cage's feed and water ports causes an inrush of high velocity air which prevents back-migration of aerosols and permits feeding and watering while eliminating need for chemical vapor decontamination. Ventilation system design permits the holding in adjacent cages of animals infected with different organisms without danger of cross-contamination; leaves the animal room odor-free; reduces required bedding changes to twice a month or less, and provides investigators with capability to control precisely individual cage ventilation rates. Forty-eight cages can be conveniently placed on a standard NIH “shoebox” cage rack (60 inches wide × 28 inches deep × 74 inches high) fitted with a simple manifold exhaust system. The entire system is mobile, requiring only an electrical power outlet. Principal application of the caging system is in the area of preventing exposure of animal caretakers to pathogenic substances associated with the animal host, and in reducing handling of animals and their exposure to extraneous contamination. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 9 PMID:5659368

Cook, Reginald O.

1968-01-01

132

Tracheostomy in mechanical ventilation.  

PubMed

Airway access for mechanical ventilation (MV) can be provided either by orotracheal intubation (OTI) or tracheostomy tube. During episodes of acute respiratory failure, patients are commonly ventilated through an orotracheal tube that represents an easy and rapid initial placement of the airway device. OTI avoids acute surgical complications such as bleeding, nerve and posterior tracheal wall injury, and late complications such as wound infection and tracheal lumen stenosis that may emerge due to tracheostomy tube placement. Tracheostomy is often considered when MV is expected to be applied for prolonged periods or for the improvement of respiratory status, as this approach provides airway protection, facilitates access for secretion removal, improves patient comfort, and promotes progression of care in and outside the intensive care unit (ICU). The aim of this review is to assess the frequency and performance of different surgical or percutaneous dilational tracheostomy and timing and safety procedures associated with the use of fiberoptic bronchoscopy and ultrasounds. Moreover, we analyzed the performance based on National European surveys to assess the current tracheostomy practice in ICUs. PMID:25111644

Terragni, Pierpaolo; Faggiano, Chiara; Martin, Erica L; Ranieri, V Marco

2014-08-01

133

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

PubMed

Implementation of care bundles for prevention of ventilator-associated pneumonia (VAP) and its impact on patient outcomes requires validation with long-term follow-up. A collaborative multi-centre cohort study was conducted in five Spanish adult intensive-care units. A care bundle approach based on five measures was implemented after a 3-month baseline period, and compliance, VAP rates, intensive-care unit length of stay (ICU LOS) and duration of mechanical ventilation were prospectively recorded for 16 months. There were 149 patients in the baseline period and 885 after the intervention. Compliance with all measures after intervention was <30% (264/885). In spite of this, VAP incidence decreased from 15.5% (23/149) to 11.7% (104/885), after the intervention (p <0.05). This reduction was significantly associated with hand hygiene (OR = 0.35), intra-cuff pressure control (OR = 0.21), oral hygiene (OR = 0.23) and sedation control (OR = 0.51). Use of the care bundle was associated with an incidence risk ratio of VAP of 0.78 (95% CI 0.15-0.99). We documented a reduction of median ICU LOS (from 10 to 6 days) and duration of mechanical ventilation (from 8 to 4 days) for patients with full bundle compliance (intervention period). Efforts on VAP prevention and outcome improvement should focus on achieving higher compliance in hand and oral hygiene, sedation protocols and intracuff pressure control. PMID:22439889

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

2013-04-01

134

A mixed GPC-H INFINITY robust cascade position-pressure control strategy for electropneumatic cylinders  

Microsoft Academic Search

A robust cascade strategy combining an outer position predictive control loop and an inner H? pressure control loop is proposed and tested on an electropneumatic testbed for parallel robotic applications. Two types of cylinders are tested, the standard double acting cylinder and the rodless one. A position\\/pressure difference (or force) strategy is developed and implemented. As the behavior of the

Lotfi Chikh; Philippe Poignet; François Pierrot; Cédric Baradat

2010-01-01

135

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

136

Cardiac gated ventilation  

NASA Astrophysics Data System (ADS)

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. We 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 50msec scan aperture. Multislice, 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. We observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a nonfailing model of the heart.

Hanson, C. William, III; Hoffman, Eric A.

1995-05-01

137

Solar ventilation and tempering  

NASA Astrophysics Data System (ADS)

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.

Adámek, Karel; Pavlů, Miloš; Bandouch, Milan

2014-08-01

138

Cardiac gated ventilation  

SciTech Connect

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.

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

139

Estimation of Lung Ventilation  

NASA Astrophysics Data System (ADS)

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.

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

140

External negative pressure ventilation techniques.  

PubMed

External ventilation was introduced at the beginning of the century to treat acute and chronic respiratory failure. Long-term negative pressure ventilation (NPV) has proved useful in patients with respiratory failure, secondary to a restrictive impairment of neuromusculoskeletal origin. Although NPV may be successfully used in acute-on-chronic respiratory failure in patients with chronic airflow obstruction (CAO), its use in the long-term management of this type of patient seems much less promising. The various types of ventilators, iron lung, pneumo-wrap and cuirass are discussed. All these prostheses, except for the pneumo-wrap, are connected to a pump able to generate negative and positive pressure. NPV must be a controlled ventilation, because an effective trigger is not yet available. The most important feature of the ventilator must be the ability to vary the ventilatory pattern to adapt the machine drive to the patient drive. The goal of NPV is not only to normalize gas exchange, but also to restore an effective spontaneous ventilation. This kind of ventilation has no negative effects on haemodynamics, because it does not vary physiological gradients of transthoracic pressure. However, due to lack of coordination between the respirator and the pharyngeal muscles of the patient, obstructive apnoeas may occur during NPV in sleeping patients. PMID:7711706

Schiavina, M; Fabiani, A; Gunella, G

1994-12-01

141

Subsurface Ventilation System Description Document  

SciTech Connect

The Subsurface Ventilation System supports the construction and operation of the subsurface repository by providing air for personnel and equipment and temperature control for the underground areas. Although the system is located underground, some equipment and features may be housed or located above ground. The system ventilates the underground by providing ambient air from the surface throughout the subsurface development and emplacement areas. The system provides fresh air for a safe work environment and supports potential retrieval operations by ventilating and cooling emplacement drifts. The system maintains compliance within the limits established for approved air quality standards. The system maintains separate ventilation between the development and waste emplacement areas. The system shall remove a portion of the heat generated by the waste packages during preclosure to support thermal goals. The system provides temperature control by reducing drift temperature to support potential retrieval operations. The ventilation system has the capability to ventilate selected drifts during emplacement and retrieval operations. The Subsurface Facility System is the main interface with the Subsurface Ventilation System. The location of the ducting, seals, filters, fans, emplacement doors, regulators, and electronic controls are within the envelope created by the Ground Control System in the Subsurface Facility System. The Subsurface Ventilation System also interfaces with the Subsurface Electrical System for power, the Monitored Geologic Repository Operations Monitoring and Control System to ensure proper and safe operation, the Safeguards and Security System for access to the emplacement drifts, the Subsurface Fire Protection System for fire safety, the Emplacement Drift System for repository performance, and the Backfill Emplacement and Subsurface Excavation Systems to support ventilation needs.

Eric Loros

2001-07-25

142

A recombinant porcine circovirus type 2 expressing the VP1 epitope of the type O foot-and-mouth disease virus is infectious and induce both PCV2 and VP1 epitope antibodies.  

PubMed

Porcine circovirus type 2 (PCV2) is the etiological agent of postweaning multisystemic wasting syndrome, a disease that causes huge economic damage in swine industry. A recombinant PCV2 expressing the neutralizing VP1 epitope (aa 141-160) of the foot-and-mouth disease virus (FMDV) was rescued using an infectious cloning technique. The PCV2 antigen and FMDV-VP1 antigenic epitope of the cloned strain recPCV2-CL-VP1 were confirmed by an immunoperoxidase monolayer assay (IPMA) and a capture enzyme-linked immunosorbent assay (ELISA). The morphological features of the recPCV2-CL-VP1 were not discernibly different from those of its parental strain (PCV2-CL). However, the recombinant virus could be differentiated from its parental virus by PCR and capture ELISA. The recPCV2-CL-VP1 was demonstrated to replicate stably in PK-15 cells through ten passages. An infection experiment using BALB/c mice showed that both recPCV2-CL-VP1 and PCV2-CL could replicate in the mice, cause various pathological changes, and induce a high level of anti-Cap antibodies. The recombinant virus emulsified with Freund's adjuvant was used to immunize BALB/c mice and induced antibodies against the FMDV-VP1 epitope. Hence, the recombinant PCV2 strain, which expressed the neutralizing FMDV-VP1 epitope, provides a valuable platform to develop novel genetic vaccines. PMID:25117547

Huang, Liping; Zhang, Feiyan; Tang, Qinghai; Wei, Yanwu; Wu, Hongli; Guo, Longjun; Fu, Yujie; Liu, Changming

2014-11-01

143

Performance of ventilators for noninvasive positive pressure ventilation in children  

E-print Network

in children with neuromuscular disease [2, 3], upper airway obstruction and sleep apnea [4], and lung diseases the preset and measured airway pressure and between the tidal volume measured by the ventilator

Boyer, Edmond

144

Ventilator-delivered mask ventilation compared with three standard methods of mask ventilation in a manikin model  

Microsoft Academic Search

BackgroundLittle is known regarding the variations in effective ventilation during bag and mask resuscitation with standard methods compared with that delivered by ventilator-delivered mask ventilation (VDMV).AimTo measure the variations in delivered airway pressure, tidal volume (TV), minute ventilation (MV) and inspiratory time during a 3-min period of mask ventilation comparing VDMV with three commonly used hand-delivered methods of bag and

M. B. Tracy; J. Klimek; H. Coughtrey; V. Shingde; G. Ponnampalam; M. Hinder; R. Maheshwari; S. K. Tracy

2011-01-01

145

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

146

Laboratory Ventilation Management Ralph Stuart, CHO  

E-print Network

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

Pawlowski, Wojtek

147

Preoperational test, vent building ventilation system  

SciTech Connect

Preoperational Test Procedure for Vent Building Ventilation System, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The Vent Building ventilation system provides ventilation, heating, cooling, and zone confinement control for the W-030 Project Vent Building. The tests verify correct System operation and correct indications displayed by the central Monitor and Control system.

Clifton, F.T., Westinghouse Hanford

1996-08-20

148

14 CFR 23.831 - Ventilation.  

...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...

2014-01-01

149

14 CFR 23.831 - Ventilation.  

Code of Federal Regulations, 2013 CFR

...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...

2013-01-01

150

Preoperational test report, vent building ventilation system  

SciTech Connect

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

Clifton, F.T.

1997-11-04

151

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

152

Reproducibility of regional lung ventilation distribution determined by electrical impedance tomography during mechanical ventilation  

Microsoft Academic Search

Electrical impedance tomography (EIT) has the potential to become a new tool for bedside monitoring of regional lung ventilation. The aim of our study was to assess the reproducibility of regional lung ventilation distribution determined by EIT during mechanical ventilation under identical ventilator settings. The experiments were performed on 10 anaesthetized supine pigs ventilated in a volume-controlled mode. EIT measurements

I Frerichs; G Schmitz; S Pulletz; G Zick; J Scholz; N Weiler

2007-01-01

153

Identifying an appropriate PCV for use in Senegal, recent insights concerning Streptococcus pneumoniae NP carriage and IPD in Dakar.  

PubMed

BackgroundSince 2000, the Global Alliance for Vaccines and Immunization (GAVI) and WHO have supported the introduction of the Pneumococcal Conjugate Vaccine (PCV) in the immunization programs of developing countries. The highest pneumococcal nasopharyngeal carriage rates have been reported (40-60%) in these countries, and the highest incidence and case fatality rates of pneumococcal infections have been demonstrated in Africa.MethodsStudies concerning nasopharyngeal pneumococcal carriage and pneumococcal infection in children less than 5 years old were conducted in Dakar from 2007 to 2008. Serotype, antibiotic susceptibility and minimum inhibitory concentrations were determined. In addition, among 17 overall publications, 6 manuscripts of the Senegalese literature published from 1972 to 2013 were selected for data comparisons.ResultsAmong the 264 children observed, 132 (50%) children generated a nasopharyngeal (NP) positive culture with Streptococcus pneumoniae. The five most prevalent serotypes, were 6B (9%), 19 F (9%), 23 F (7.6%), 14 (7.6%) and 6A (6.8%). Fifteen percent of the strains (20/132) showed reduced susceptibility to penicillin and 3% (4/132) showed reduced susceptibility to anti-pneumococcal fluoroquinolones. Among the 196 suspected pneumococcal infections, 62 (31.6%) Streptococcus pneumoniae were isolated. Serogroup 1 was the most prevalent serotype (21.3%), followed by 6B (14.9%), 23 F (14.9%) and 5 (8.5%). Vaccine coverage for PCV-7, PCV-10 and PCV-13, were 36.2% (17/47), 66% (31/47) and 70.2% (33/47) respectively. Reduced susceptibility to penicillin and anti-pneumococcal fluoroquinolones was 6.4% and 4.3%, respectively, and the overall lethality was 42.4% (14/33).ConclusionsThis study confirms a high rate of carriage and disease caused by Streptococcus pneumoniae serotypes contained within the current generation of pneumococcal conjugate vaccines and consistent with reports from other countries in sub-Saharan Africa prior to PCV introduction. Antimicrobial resistance in this small unselected sample confirms a low rate of antibiotic resistance. Case-fatality is high. Introduction of a high valency pneumococcal vaccine should be a priority for health planners with the establishment of an effective surveillance system to monitor post vaccine changes. PMID:25471219

Ba, Fatim; Seck, Abdoulaye; Bâ, Mamadou; Thiongane, Aliou; Cissé, Moussa; Seck, Khady; Ndour, Madeleine; Boisier, Pascal; Garin, Benoit

2014-12-01

154

Equivalence in Ventilation and Indoor Air Quality  

SciTech Connect

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.

Sherman, Max; Walker, Iain; Logue, Jennifer

2011-08-01

155

Literature Review of Displacement Ventilation  

E-print Network

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...

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

156

Transtracheal ventilation in oral surgery.  

PubMed Central

The use of transtracheal ventilation as a routine method of ventilation during anaesthesia for 60 patients with gross pathology requiring oral surgery is reported. Theoretical hazards of the technique and protection of the airway are discussed. There were no serious complications in this series. The technique is recommended as a simple and safe alternative to blind nasal intubation. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:6614769

Layman, P. R.

1983-01-01

157

Ventilation Model and Analysis Report  

SciTech Connect

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.

V. Chipman

2003-07-18

158

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

SciTech Connect

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.

Daugherty, W.

2014-08-06

159

Design of Characteristics of Air Pressure Controlled Hydraulic Shock Absorbers in an Intercity Bus  

Microsoft Academic Search

The air pressure controlled hydraulic telescopic shock absorber of axles air suspension is capable of changing its damping\\u000a force in dependence on air pressure in air springs. Air pressure in springs rises as vehicle loading grows and damping forces\\u000a in the shock absorbers increase. When reducing vehicle loading, air pressure in springs drops and causes decrease in damping\\u000a forces in

Pavel Polach; Michal Hajžman

160

21 CFR 868.5905 - Noncontinuous ventilator (IPPB).  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Noncontinuous ventilator (IPPB). 868.5905 Section 868...Devices § 868.5905 Noncontinuous ventilator (IPPB). (a) Identification. A noncontinuous ventilator (intermittent positive...

2011-04-01

161

21 CFR 868.5905 - Noncontinuous ventilator (IPPB).  

...2014-04-01 false Noncontinuous ventilator (IPPB). 868.5905 Section 868...Devices § 868.5905 Noncontinuous ventilator (IPPB). (a) Identification. A noncontinuous ventilator (intermittent positive...

2014-04-01

162

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

163

21 CFR 868.5905 - Noncontinuous ventilator (IPPB).  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Noncontinuous ventilator (IPPB). 868.5905 Section 868...Devices § 868.5905 Noncontinuous ventilator (IPPB). (a) Identification. A noncontinuous ventilator (intermittent positive...

2010-04-01

164

21 CFR 868.5905 - Noncontinuous ventilator (IPPB).  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Noncontinuous ventilator (IPPB). 868.5905 Section 868...Devices § 868.5905 Noncontinuous ventilator (IPPB). (a) Identification. A noncontinuous ventilator (intermittent positive...

2012-04-01

165

21 CFR 868.5905 - Noncontinuous ventilator (IPPB).  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Noncontinuous ventilator (IPPB). 868.5905 Section 868...Devices § 868.5905 Noncontinuous ventilator (IPPB). (a) Identification. A noncontinuous ventilator (intermittent positive...

2013-04-01

166

Impact of routine PCV7 (Prevenar) vaccination of infants on the clinical and economic burden of pneumococcal disease in Malaysia  

PubMed Central

Background Pneumococcal disease is the leading cause of vaccine-preventable death in children younger than 5 years of age worldwide. The World Health Organization recommends pneumococcal conjugate vaccine as a priority for inclusion into national childhood immunization programmes. Pneumococcal vaccine has yet to be included as part of the national vaccination programme in Malaysia although it has been available in the country since 2005. This study sought to estimate the disease burden of pneumococcal disease in Malaysia and to assess the cost effectiveness of routine infant vaccination with PCV7. Methods A decision model was adapted taking into consideration prevalence, disease burden, treatment costs and outcomes for pneumococcal disease severe enough to result in a hospital admission. Disease burden were estimated from the medical records of 6 hospitals. Where local data was unavailable, model inputs were obtained from international and regional studies and from focus group discussions. The model incorporated the effects of herd protection on the unvaccinated adult population. Results At current vaccine prices, PCV7 vaccination of 90% of a hypothetical 550,000 birth cohort would incur costs of RM 439.6 million (US$128 million). Over a 10 year time horizon, vaccination would reduce episodes of pneumococcal hospitalisation by 9,585 cases to 73,845 hospitalisations with cost savings of RM 37.5 million (US$10.9 million) to the health system with 11,422.5 life years saved at a cost effectiveness ratio of RM 35,196 (US$10,261) per life year gained. Conclusions PCV7 vaccination of infants is expected to be cost-effective for Malaysia with an incremental cost per life year gained of RM 35,196 (US$10,261). This is well below the WHO's threshold for cost effectiveness of public health interventions in Malaysia of RM 71,761 (US$20,922). PMID:21936928

2011-01-01

167

Residential ventilation standards scoping study  

SciTech Connect

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).

McKone, Thomas E.; Sherman, Max H.

2003-10-01

168

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

SciTech Connect

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.

Daugherty, W. L.

2013-09-03

169

REVIEW Open Access Ventilator-induced lung injury: historical  

E-print Network

REVIEW Open Access Ventilator-induced lung injury: historical perspectives and clinical Mechanical ventilation can produce lung physiological and morphological alterations termed ventilator to mechanically ventilated patients, and thus of the stress applied to their lungs, unambiguously contributed

Paris-Sud XI, Université de

170

30 CFR 57.8532 - Opening and closing ventilation doors.  

Code of Federal Regulations, 2012 CFR

...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...

2012-07-01

171

30 CFR 57.8532 - Opening and closing ventilation doors.  

Code of Federal Regulations, 2011 CFR

...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...

2011-07-01

172

30 CFR 57.8532 - Opening and closing ventilation doors.  

Code of Federal Regulations, 2013 CFR

...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...

2013-07-01

173

30 CFR 57.8532 - Opening and closing ventilation doors.  

...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...

2014-07-01

174

30 CFR 57.8532 - Opening and closing ventilation doors.  

Code of Federal Regulations, 2010 CFR

...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...

2010-07-01

175

33 CFR 183.620 - Natural ventilation system.  

...2014-07-01 false Natural ventilation system. 183.620 Section 183.620 Navigation...Ventilation § 183.620 Natural ventilation system...the atmosphere, a natural ventilation system...paragraph (c) of this section; (3)...

2014-07-01

176

33 CFR 183.620 - Natural ventilation system.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Natural ventilation system. 183.620 Section 183.620 Navigation...Ventilation § 183.620 Natural ventilation system...the atmosphere, a natural ventilation system...paragraph (c) of this section; (3)...

2013-07-01

177

33 CFR 183.620 - Natural ventilation system.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Natural ventilation system. 183.620 Section 183.620 Navigation...Ventilation § 183.620 Natural ventilation system...the atmosphere, a natural ventilation system...paragraph (c) of this section; (3)...

2012-07-01

178

33 CFR 183.620 - Natural ventilation system.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Natural ventilation system. 183.620 Section 183.620 Navigation...Ventilation § 183.620 Natural ventilation system...the atmosphere, a natural ventilation system...paragraph (c) of this section; (3)...

2011-07-01

179

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

PubMed Central

Background. There are modes of mechanical ventilation that can select ventilator settings with computer controlled algorithms (targeting schemes). Two examples are adaptive support ventilation (ASV) and mid-frequency ventilation (MFV). We studied how different clinician-chosen ventilator settings are from these computer algorithms under different scenarios. Methods. A survey of critical care clinicians provided reference ventilator settings for a 70?kg paralyzed patient in five clinical/physiological scenarios. The survey-derived values for minute ventilation and minute alveolar ventilation were used as goals for ASV and MFV, respectively. A lung simulator programmed with each scenario's respiratory system characteristics was ventilated using the clinician, ASV, and MFV settings. Results. Tidal volumes ranged from 6.1 to 8.3?mL/kg for the clinician, 6.7 to 11.9?mL/kg for ASV, and 3.5 to 9.9?mL/kg for MFV. Inspiratory pressures were lower for ASV and MFV. Clinician-selected tidal volumes were similar to the ASV settings for all scenarios except for asthma, in which the tidal volumes were larger for ASV and MFV. MFV delivered the same alveolar minute ventilation with higher end expiratory and lower end inspiratory volumes. Conclusions. There are differences and similarities among initial ventilator settings selected by humans and computers for various clinical scenarios. The ventilation outcomes are the result of the lung physiological characteristics and their interaction with the targeting scheme. PMID:23119152

Mireles-Cabodevila, Eduardo; Diaz-Guzman, Enrique; Arroliga, Alejandro C.; Chatburn, Robert L.

2012-01-01

180

14 CFR 252.9 - Ventilation systems.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever the ventilation system is not fully functioning. Fully...

2011-01-01

181

14 CFR 252.9 - Ventilation systems.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever the ventilation system is not fully functioning. Fully...

2010-01-01

182

JAMA Patient Page: Ventilator-Associated Pneumonia  

MedlinePLUS

... of the American Medical Association JAMA PATIENT PAGE Ventilator-Associated Pneumonia V entilator-associated pneumonia , defined as ... and life-threatening infection. Because individuals who contract ventilator-associated pneumonia are already critically ill (requiring mechanical ...

183

14 CFR 121.219 - Ventilation.  

Code of Federal Regulations, 2011 CFR

...and Space 3 2011-01-01 2011-01-01 false Ventilation. 121.219 Section 121.219 Aeronautics and Space...OPERATIONS Special Airworthiness Requirements § 121.219 Ventilation. Each passenger or crew compartment must be suitably...

2011-01-01

184

14 CFR 125.117 - Ventilation.  

...and Space 3 2014-01-01 2014-01-01 false Ventilation. 125.117 Section 125.117 Aeronautics and Space...AIRCRAFT Special Airworthiness Requirements § 125.117 Ventilation. Each passenger or crew compartment must be suitably...

2014-01-01

185

14 CFR 125.117 - Ventilation.  

Code of Federal Regulations, 2012 CFR

...and Space 3 2012-01-01 2012-01-01 false Ventilation. 125.117 Section 125.117 Aeronautics and Space...AIRCRAFT Special Airworthiness Requirements § 125.117 Ventilation. Each passenger or crew compartment must be suitably...

2012-01-01

186

14 CFR 121.219 - Ventilation.  

...and Space 3 2014-01-01 2014-01-01 false Ventilation. 121.219 Section 121.219 Aeronautics and Space...OPERATIONS Special Airworthiness Requirements § 121.219 Ventilation. Each passenger or crew compartment must be suitably...

2014-01-01

187

14 CFR 29.831 - Ventilation.  

...and Space 1 2014-01-01 2014-01-01 false Ventilation. 29.831 Section 29.831 Aeronautics and Space...Construction Personnel and Cargo Accommodations § 29.831 Ventilation. (a) Each passenger and crew compartment must...

2014-01-01

188

14 CFR 121.219 - Ventilation.  

Code of Federal Regulations, 2012 CFR

...and Space 3 2012-01-01 2012-01-01 false Ventilation. 121.219 Section 121.219 Aeronautics and Space...OPERATIONS Special Airworthiness Requirements § 121.219 Ventilation. Each passenger or crew compartment must be suitably...

2012-01-01

189

46 CFR 194.10-25 - Ventilation.  

Code of Federal Regulations, 2010 CFR

...MATERIALS Magazines § 194.10-25 Ventilation. (a) Integral magazines. (1) All integral magazines shall be provided with natural or mechanical ventilation. Design calculations shall be submitted demonstrating that the system...

2010-10-01

190

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

PubMed Central

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

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

2014-01-01

191

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

SciTech Connect

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.

Floersch, R.H.

1981-04-01

192

Ventilator-Associated Pneumonia: A Review  

Microsoft Academic Search

Ventilator-associated pneumonia is the most frequent intensive care unit (ICU)-related infection in patients requiring mechanical ventilation. In contrast to other ICU-related infections, which have a low mortality rate, the mortality rate for ventilator-associated pneumonia ranges from 20% to 50%. These clinically significant infections prolong duration of mechanical ventilation and ICU length of stay, underscoring the financial burden these infections impose

Kimberly A. Davis

2006-01-01

193

Practice changing mature results of RTOG study 9802: another positive PCV trial makes adjuvant chemotherapy part of standard of care in low-grade glioma.  

PubMed

The long-term follow-up of the RTOG 9802 trial that compared 54 Gy of radiotherapy (RT) with the same RT followed by adjuvant procarbazine, CCNU, and vincristine (PCV) chemotherapy in high-risk low-grade glioma shows a major increase in survival after adjuvant PCV chemotherapy. Median overall survival increased from 7.8 years to 13.3 years, with a hazard ratio of death of 0.59 (log rank: P = .002). This increase in survival was observed despite the fact that 77% of patients who progressed after RT alone received salvage chemotherapy. With this outcome, RT + PCV is now to be considered standard of care for low-grade glioma requiring postsurgical adjuvant treatment. Unfortunately, studies on molecular correlates associated with response are still lacking. This is now the third trial showing benefit from the addition of PCV to RT in grade II or III diffuse glioma. The optimal parameter for selecting patients for adjuvant PCV has not yet been fully elucidated, but several candidate markers have so far emerged. It is still unclear whether temozolomide can replace PCV and whether initial management with chemotherapy only is a safe initial treatment. Potentially, that may adversely affect overall survival, but concerns for delayed RT-induced neurotoxicity may limit acceptance of early RT in patients with expected long term survival. The current evidence supports that in future trials, grades II and III tumors with similar molecular backgrounds should be combined, and trials should focus on molecular glial subtype regardless of grade. PMID:25355680

van den Bent, Martin J

2014-12-01

194

The fluid mechanics of natural ventilation  

Microsoft Academic Search

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

Paul Linden

1999-01-01

195

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

196

Kent Scientific Corporation DUAL MODE VENTILATOR  

E-print Network

Kent Scientific Corporation TOPO DUAL MODE VENTILATOR Operating Manual July 2005 #12;Kent of the labeling on the front of the ventilator may not completely match the digital photographs in this manual.2 Exhaust 8.3 Power Switch & Power Receptacle 9.0 Connecting the Animal to the Ventilator 10.0 Operation 10

197

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

198

WASTE HANDLING BUILDING VENTILATION SYSTEM DESCRIPTION DOCUMENT  

Microsoft Academic Search

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

P. A. Kumar

2000-01-01

199

WASTE TREATMENT BUILDING VENTILATION SYSTEM DESCRIPTION DOCUMENT  

Microsoft Academic Search

The Waste Treatment 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 Treatment Building (WTB). 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

P. A. Kumar

2000-01-01

200

9 CFR 91.21 - Ventilation.  

Code of Federal Regulations, 2011 CFR

...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...

2011-01-01

201

46 CFR 168.15-50 - Ventilation.  

Code of Federal Regulations, 2013 CFR

...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,...

2013-10-01

202

9 CFR 91.21 - Ventilation.  

...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...

2014-01-01

203

46 CFR 194.15-5 - Ventilation.  

Code of Federal Regulations, 2011 CFR

...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...

2011-10-01

204

9 CFR 91.21 - Ventilation.  

Code of Federal Regulations, 2010 CFR

...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...

2010-01-01

205

46 CFR 194.15-5 - Ventilation.  

Code of Federal Regulations, 2012 CFR

...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...

2012-10-01

206

9 CFR 91.21 - Ventilation.  

Code of Federal Regulations, 2012 CFR

...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...

2012-01-01

207

46 CFR 194.15-5 - Ventilation.  

Code of Federal Regulations, 2013 CFR

...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...

2013-10-01

208

14 CFR 27.831 - Ventilation.  

...and Space 1 2014-01-01 2014-01-01 false Ventilation. 27.831 Section 27.831 Aeronautics and Space...Construction Personnel and Cargo Accommodations § 27.831 Ventilation. (a) The ventilating system for the pilot and...

2014-01-01

209

9 CFR 91.21 - Ventilation.  

Code of Federal Regulations, 2013 CFR

...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...

2013-01-01

210

46 CFR 168.15-50 - Ventilation.  

Code of Federal Regulations, 2010 CFR

...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,...

2010-10-01

211

Formaldehyde Transfer in Residential Energy Recovery Ventilators  

E-print Network

design used in many energy recovery ventilators (ERVs) is designed to transfer heat and moisture betweenFormaldehyde 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

212

46 CFR 168.15-50 - Ventilation.  

Code of Federal Regulations, 2011 CFR

...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,...

2011-10-01

213

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

PubMed Central

Background In ventilated newborns the use of multiple breath washout (MBW) techniques for measuring both lung volume and ventilation inhomogeneity (VI) is hampered by the comparatively high dead space fraction. We studied how changes in ventilator settings affected VI indices in this particular population. Methods Using a computer simulation of a uniformly ventilated volume the interaction between VI indices (lung clearance index (LCI), moment ratios (M1/M0, M2/M0, AMDN1, AMDN2) of the washout curve) and tidal volume (VT), dead space (VD) and functional residual capacity (FRC) were calculated. The theoretical results were compared with measurements in 15 ventilated piglets (age <12 h, median weight 1135 g) by increasing the peak inspiratory pressure (PIP). FRC and VI indices were measured by MBW using 0.8% heptafluoropropane as tracer gas. Results The computer simulation showed that the sensitivity of most VI indices to changes in VD/VT and VT/FRC increase, in particular for VD/VT > 0.5. In piglets, the raised PIP caused a significant increase of VT from 15.4 ± 9.5 to 21.9 ± 14.7 (p = 0.003) and of the FRC from 31.6 ± 14.7 mL to 35.0 ± 15.9 mL (p = 0.006), whereas LCI (9.15 ± 0.75 to 8.55 ± 0.74, p = 0.019) and the moment ratios M1/M0, M2/M0 (p < 0.02) decreased significantly. No significant changes were seen in AMDN1 and AMDN2. The within-subject variability of the VI indices (coefficient of variation in brackets) was distinctly higher (LCI (9.8%), M1/M0 (6.6%), M2/M0 (14.6%), AMDN1 (9.1%), AMDN2 (16.3%)) compared to FRC measurements (5.6%). Computer simulations showed that significant changes in VI indices were exclusively caused by changes in VT and FRC and not by an improvement of the homogeneity of alveolar ventilation. Conclusion In small ventilated lungs with a high dead space fraction, indices of VI may be misinterpreted if the changes in ventilator settings are not considered. Computer simulations can help to prevent this misinterpretation. PMID:16916474

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

2006-01-01

214

Evaluation of Swedish ventilation systems  

Microsoft Academic Search

It is of great importance to the indoor air quality that the ventilation systems, not only directly after taken into operation, operate as they were designed and according to the regulations. The objective of the paper is to show how well the systems satisfy the national regulations after being in operation for several years and what their main defects are.

F. Engdahl

1998-01-01

215

Particle deposition in ventilation ducts  

Microsoft Academic Search

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

Sippola; Mark R

2002-01-01

216

Preventing Ventilation On Sailboard Skegs  

NASA Technical Reports Server (NTRS)

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.

Caldwell, Richard A.

1990-01-01

217

Reliability analysis of ventilation systems  

SciTech Connect

This article proposes design parameters and systems analysis procedures for a mine ventilation system which incorporates backup and redundancy in its switching and fan systems in order to optimize the safety and reliability of the overall system. Failure probabilities due to frost buildup and other factors are assessed and several design regimes are comparatively evaluated. Diagrams are included.

Petrov, N.N.; Butorina, O.S.

1987-09-01

218

Night ventilation control strategies in office buildings  

SciTech Connect

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)

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

2009-10-15

219

Clinical review: Liberation from mechanical ventilation  

PubMed Central

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 mechanical ventilation, including ventilator induced lung injury, ventilator associated pneumonia, increased length of ICU and hospital stay, and increased cost of care delivery. This review highlights the recent developments in assessing and testing for readiness of liberation from mechanical ventilation, the etiology of weaning failure, the value of weaning protocols, and a simple practical approach for liberation from mechanical ventilation. PMID:18710593

El-Khatib, Mohamad F; Bou-Khalil, Pierre

2008-01-01

220

Summary of human responses to ventilation  

SciTech Connect

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.

Seppanen, Olli A.; Fisk, William J.

2004-06-01

221

Development of an in situ assay for simultaneous detection of the genomic and replicative form of PCV2 using padlock probes and rolling circle amplification  

Microsoft Academic Search

BACKGROUND: In this study we utilized padlock probes and rolling circle amplification as a mean to detect and study the replication of porcine circovirus type 2 (PCV2) in cultured cells and in infected tissue. Porcine circovirus type 2 is a single-stranded circular DNA virus associated with several severe diseases, porcine circovirus diseases (PCVD) in pigs, such as postweaning multisystemic wasting

Sara Henriksson; Anne-Lie Blomström; Lisbeth Fuxler; Caroline Fossum; Mikael Berg; Mats Nilsson

2011-01-01

222

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

NASA Technical Reports Server (NTRS)

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.

Saiidi, M. J.

1988-01-01

223

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

SciTech Connect

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

Kavaklioglu, K.; Ikonomopoulos, A. (Univ. of Tennessee, Knoxville (United States))

1993-01-01

224

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

NASA Technical Reports Server (NTRS)

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

1996-01-01

225

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

NASA Technical Reports Server (NTRS)

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

1996-01-01

226

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

NASA Technical Reports Server (NTRS)

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

1996-01-01

227

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

NASA Technical Reports Server (NTRS)

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

1996-01-01

228

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

NASA Technical Reports Server (NTRS)

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.

Kassemi, Mohammad; Hylton, Sonya; Kartizova, Olga

2013-01-01

229

Prevention of ventilator-associated pneumonia.  

PubMed

Ventilator-associated pneumonia is the commonest, yet mostly preventable, infection in mechanically ventilated patients. Successful control of ventilator-associated pneumonia can save hospitalisation cost, and is possible by using a multidisciplinary clinical and administrative approach. The ventilator-associated pneumonia rate should be expressed as the number of ventilator-associated pneumonia days per 1000 ventilator days to take into account the device-utilisation duration for meaningful comparison. Various strategies address the issue, including general infection control measures, body positioning, intubation and mechanical ventilation, oral and gastro-intestinal tract, endotracheal tube, airway pressure, cuff pressure, selective digestive and/or oropharyngeal decontamination, and probiotic or early antibiotic treatment, as well as overall administration at a policy level. The rationale and controversy of these approaches are discussed in this article. The authors suggest that all units treating mechanically ventilated patients should have a ventilator-associated pneumonia prevention protocol in place, and ventilator-associated pneumonia should be seriously considered as a key performance indicator in local intensive care units. PMID:25593193

Lau, A Cw; So, H M; Tang, S L; Yeung, A; Lam, S M; Yan, W W

2015-02-01

230

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

NASA Astrophysics Data System (ADS)

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

Schnabel, Christian; Meissner, Sven; Koch, Edmund

2011-06-01

231

The comparative profile of lymphoid cells and the T and B cell spectratype of germ-free piglets infected with viruses SIV, PRRSV or PCV2.  

PubMed

Lymphocyte subsets isolated from germ-free piglets experimentally infected with swine influenza virus (SIV), porcine reproductive and respiratory syndrome virus (PRRSV) or porcine circovirus type 2 (PCV2) were studied and the profile of these subsets among these three infections was monitored. Germ-free piglets were used since their response could be directly correlated to the viral infection. Because SIV infections are resolved even by colostrum-deprived neonates whereas PRRSV and PCV2 infections are not, SIV was used as a benchmark for an effectively resolved viral infection. PRRSV caused a large increase in the proportion of lymphocytes at the site of infection and rapid differentiation of B cells leading to a high level of Ig-producing cells but a severe reduction in CD2-CD21+ primed B cells. Unlike SIV and PCV2, PRRSV also caused an increase in terminally differentiated subset of CD2+CD8?+ ?? cells and polyclonal expansion of major V? families suggesting that non-specific helper T cells drive swift B cell activation. Distinct from infections with SIV and PRRSV, PCV2 infection led to the: (a) prevalence of MHC-II+ T cytotoxic cells, (b) restriction of the T helper compartment in the respiratory tract, (c) generation of a high proportion of FoxP3+ T cells in the blood and (d) selective expansion of IgA and IgE suggesting this virus elicits a mucosal immune response. Our findings suggest that PRRSV and PCV2 may negatively modulate the host immune system by different mechanisms which may explain their persistence. PMID:25186625

Sinkora, Marek; Butler, John E; Lager, Kelly M; Potockova, Hana; Sinkorova, Jana

2014-01-01

232

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

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

2014-01-01

233

Ventilation effects on combustion products.  

PubMed

The effects of fire ventilation on combustion products are expressed in terms of relationship between concentration of products and equivalence ratio, phi. For well-ventilated fires, phi < 1.0, where mostly heat and products of complete combustion (such as CO2 and water) are generated. For ventilation-controlled fires, phi > 1.0, where mostly products of incomplete combustion are generated with very high concentrations in a transition region for phi between 1.0 and 3.5. The high concentrations of the products of incomplete combustion are dangerous to life and property. For halogenated materials, this condition occurs for phi < 1.0. The non-flaming region for fires is found to exist for phi > 3.5. Correlations have been developed for the prediction of concentrations of products at various phi values for the assessment of combustion toxicity and smoke damage hazards by zone fire models, such as Hazard 1. The correlations show good agreement with the measured concentrations. The concentrations of the products of incomplete combustion depend on the chemical structures of the materials. For the same phi values, the carbon monoxide concentrations are higher for materials with oxygen atoms in the structure, whereas smoke concentrations are higher for materials with carbon and hydrogen atoms in the structure. The results of the study suggest that it is necessary to examine the combustion behaviour of advanced materials for use in aircraft and other critical applications at various phi values, along with the toxicity experiments. PMID:9016749

Tewarson, A

1996-12-31

234

Particle deposition in ventilation ducts  

SciTech Connect

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.

Sippola, Mark R.

2002-09-01

235

CFD applications in tunnel ventilation analysis  

SciTech Connect

Longitudinal ventilation systems in transit and rail tunnels are typically analyzed by one dimensional ventilation network simulation models, such as the Subway Environment Simulation (SES) program. However, in recent years computational fluid dynamics (CFD) modeling has been utilized in conjunction with one-dimensional ventilation network programs to study ventilation systems for large volume spaces such as transit stations and rail overbuilds, as well as for vehicular tunnels. CFD uses numerical methods to simulate complex fluid flow phenomena in three dimensions to predict the distribution of velocity, pressure, temperature, concentration, and other relevant variables throughout the volume. This paper presents an overview of CFD study results from emergency ventilation analysis for a transit station and both emergency ventilation and diesel emissions analysis for a rail overbuild.

Ray, R.E. Jr.; Zigh, A.

1999-07-01

236

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

237

Level of blood pressure control among hypertensive patients on follow-up in a Regional Referral Hospital in Central Kenya  

PubMed Central

Introduction Uncontrolled hypertension is a leading modifiable risk factor for cardiovascular disease morbidity and mortality. Data on adequacy of blood pressure control in Kenya is scarce. This study aimed at assessing the level of blood pressure control among hypertensive patients on follow-up in a regional referral hospital. Methods Data regarding blood pressure, antihypertensive medication use, and comorbidities was abstracted from medical records of 452 hypertensive patients seen in Nyeri Provincial General Hospital between January and March 2013. Adequate blood pressure control was defined as a systolic pressure < 140 mmHg (< 130 mmHg for diabetic hypertensive patients) and a diastolic pressure < 90 mmHg (< 80 mmHg for diabetic hypertensive patients). Data was entered and analyzed using STATA 9 (StataCorp, Inc, Texas, USA). Results Only 33.4% of patients had a blood pressure within the recommended limits. In multivariate analysis, using a calcium channel blocker was significantly associated with good blood pressure control (OR, 2.1; 95% CI, 1.4, 3.3). On the other hand, old age (? 60 years), being diabetic, and the use of three or more antihypertensive drugs were associated with reduced odds of good blood pressure control (OR, 0.64; 95% CI, 0.43; OR, 0.54; 95% CI, 0.36, 0.81; and OR, 0.41; 95% CI, 0.26, 0.64, respectively). Conclusion Poorly controlled blood pressure is an important public health concern among hypertensive patients in this region. Elderly patients, those with diabetes, and those on multidrug regimens are at higher risk for poor blood pressure control and warrant closer attention. PMID:25489372

Mutua, Ernest Muthami; Gitonga, Moses Mwangi; Mbuthia, Beth; Muiruri, Nelly; Cheptum, Joyce Jebet; Maingi, Thomas

2014-01-01

238

The ``Temperature Amplifier'': an Innovative Application of Pressure-Controlled Heat-Pipes for Calibration of PRTs and Thermocouples  

NASA Astrophysics Data System (ADS)

At high temperature (from 600 °C to 962 °C) calibration by comparison of platinum resistance thermometers (PRTs) is limited by the instability and the reliability of the standard high-temperature PRT and by the temperature uniformity in the working volume of furnaces equipped with comparison blocks. To improve its calibration-comparison capability, BNM-INM is studying the possibility of connecting several pressure-controlled heat-pipes, filled with different working fluids, simultaneously to the same pressure control system. The experimental apparatus, called a "temperature amplifier," is composed of three heat-pipes filled with sodium (Na), potassium (K), and dodecane (Do).

Renaot, E.; Elgourdou, M.; Bonnier, G.

2003-09-01

239

Ventilation of sheep and goat barns.  

PubMed

Good ventilation is an important part of any livestock housing system. It may be accomplished by either natural or mechanical means. Generally, except for buildings that must be kept at warm, nonfluctuating temperatures, naturally ventilated cold housing is satisfactory for sheep and goats provided it is dry and draft-free in pen and resting areas, and air exchange is taking place at a rate high enough to remove moisture, gases, and airborne disease organisms from the building. Understanding the importance of site location, building orientation, and principles of ventilation design increases the likelihood of successful barn ventilation. PMID:2245366

Collins, E R

1990-11-01

240

Ventilation and Work Performance in Office Work  

SciTech Connect

Outdoor air ventilation rates vary considerably between and within buildings. The purpose of this study was to evaluate the potential work performance benefits of increased ventilation. They analyzed the literature relating work performance with ventilation rate and employed statistical analyses with weighting factors to combine the results of different studies. The studies included in the review assessed performance of various tasks in laboratory experiments and measured performance at work in real buildings. Almost all studies found increases in performance with higher ventilation rates. The studies indicated typically a 1-3% improvement in average performance per 10 L/s-person increase in outdoor air ventilation rate. The performance increase per unit increase in ventilation was bigger with ventilation rates below 20 L/s-person and almost negligible with ventilation rates over 45 L/s-person. The performance increase was statistically significant with increased ventilation rates up to 15 L/s-person with 95% CI and up to 17 L/s-person with 90% CI.

Seppanen, Olli; Fisk, William J.; Lei, Q.H.

2005-07-01

241

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

Microsoft Academic Search

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

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

1993-01-01

242

Interactive Simulation System for Artificial Ventilation on the Internet: Virtual Ventilator  

Microsoft Academic Search

Objective. To develop an interactive simulation system “virtual ventilator” that demonstrates the dynamics of pressure and flow in the respiratory system under the combination of spontaneous breathing, ventilation modes, and ventilator options. The simulation system was designed to be used by unexperienced health care professionals as a self-training tool. Methods. The system consists of a simulation controller and three modules:

Akihiro Takeuchi; Tadashi Abe; Minoru Hirose; Koichi Kamioka; Atsushi Hamada; Noriaki Ikeda

2004-01-01

243

Severe impairment in lung function induced by high peak airway pressure during mechanical ventilation. An experimental study.  

PubMed

We explored the pulmonary effects of continuous mechanical ventilation (MV) at a peak inspiratory pressure of 50 cm H2O in healthy, paralyzed, and anesthetized adult sheep during a period of 48 h. The 9 control sheep (Group A) were ventilated with 40% oxygen at a tidal volume of about 10 ml/kg and a peak inspiratory pressure of 15 to 20 cm H2O. All these animals remained stable throughout the 48 h of MV with no change in lung function. The 7 sheep in Group B were ventilated with 40% oxygen using a pressure-controlled ventilator at 50 cm H2O peak inspiratory pressure, at a VT of 50 to 70 ml/kg. All sheep in Group B developed severe respiratory failure and died or were killed within 2 to 35 h, and showed parenchymal consolidation at autopsy. The 9 sheep in Group C were ventilated as in Group B, except that 3.8% CO2 was added to the inspired gases: the Group C animals deteriorated more slowly, with little change in PaO2 but with a severely reduced FRC, VT, total static lung compliance, and grossly abnormal lungs at autopsy. We conclude that in this model, mechanical ventilation at peak airway pressure of 50 cm H2O will lead to progressive impairment in pulmonary mechanics, lung function, acute respiratory failure, and alveolar cellular dysfunction, as demonstrated by highly abnormal minimal surface tension values of saline lung lavage fluid in both study groups. PMID:3544984

Kolobow, T; Moretti, M P; Fumagalli, R; Mascheroni, D; Prato, P; Chen, V; Joris, M

1987-02-01

244

21 CFR 868.5955 - Intermittent mandatory ventilation attachment.  

Code of Federal Regulations, 2011 CFR

... (a) Identification. An intermittent mandatory ventilation (IMV) attachment is a device attached to a mechanical ventilator that allows spontaneous breathing by a patient while providing mechanical ventilation at a preset rate. (b)...

2011-04-01

245

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

246

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

247

46 CFR 190.15-10 - Ventilation for closed spaces.  

Code of Federal Regulations, 2011 CFR

...ventilated. Means shall be provided to close off all vents and ventilators. (b) Means shall be provided for stopping all fans...storerooms, and machinery spaces and for closing all doorways, ventilators, and annular spaces around funnels and other openings...

2011-10-01

248

21 CFR 868.5925 - Powered emergency ventilator.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Powered emergency ventilator. 868.5925 Section 868.5925...Devices § 868.5925 Powered emergency ventilator. (a) Identification. A powered emergency ventilator is a demand valve or inhalator...

2012-04-01

249

46 CFR 72.15-15 - Ventilation for closed spaces.  

Code of Federal Regulations, 2012 CFR

...ventilated. Means shall be provided to close off all vents and ventilators. (b) Means shall be provided for stopping all fans...machinery and cargo spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings...

2012-10-01

250

46 CFR 190.15-10 - Ventilation for closed spaces.  

Code of Federal Regulations, 2013 CFR

...ventilated. Means shall be provided to close off all vents and ventilators. (b) Means shall be provided for stopping all fans...storerooms, and machinery spaces and for closing all doorways, ventilators, and annular spaces around funnels and other openings...

2013-10-01

251

21 CFR 868.5955 - Intermittent mandatory ventilation attachment.  

... (a) Identification. An intermittent mandatory ventilation (IMV) attachment is a device attached to a mechanical ventilator that allows spontaneous breathing by a patient while providing mechanical ventilation at a preset rate. (b)...

2014-04-01

252

21 CFR 868.5925 - Powered emergency ventilator.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Powered emergency ventilator. 868.5925 Section 868.5925...Devices § 868.5925 Powered emergency ventilator. (a) Identification. A powered emergency ventilator is a demand valve or inhalator...

2013-04-01

253

21 CFR 868.5955 - Intermittent mandatory ventilation attachment.  

Code of Federal Regulations, 2012 CFR

... (a) Identification. An intermittent mandatory ventilation (IMV) attachment is a device attached to a mechanical ventilator that allows spontaneous breathing by a patient while providing mechanical ventilation at a preset rate. (b)...

2012-04-01

254

21 CFR 868.5955 - Intermittent mandatory ventilation attachment.  

Code of Federal Regulations, 2013 CFR

... (a) Identification. An intermittent mandatory ventilation (IMV) attachment is a device attached to a mechanical ventilator that allows spontaneous breathing by a patient while providing mechanical ventilation at a preset rate. (b)...

2013-04-01

255

21 CFR 868.5935 - External negative pressure ventilator.  

...false External negative pressure ventilator. 868.5935 Section 868.5935...5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung,...

2014-04-01

256

46 CFR 190.15-10 - Ventilation for closed spaces.  

Code of Federal Regulations, 2012 CFR

...ventilated. Means shall be provided to close off all vents and ventilators. (b) Means shall be provided for stopping all fans...storerooms, and machinery spaces and for closing all doorways, ventilators, and annular spaces around funnels and other openings...

2012-10-01

257

46 CFR 72.15-15 - Ventilation for closed spaces.  

...ventilated. Means shall be provided to close off all vents and ventilators. (b) Means shall be provided for stopping all fans...machinery and cargo spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings...

2014-10-01

258

21 CFR 868.5935 - External negative pressure ventilator.  

Code of Federal Regulations, 2011 CFR

...false External negative pressure ventilator. 868.5935 Section 868.5935...5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung,...

2011-04-01

259

21 CFR 868.5925 - Powered emergency ventilator.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Powered emergency ventilator. 868.5925 Section 868.5925...Devices § 868.5925 Powered emergency ventilator. (a) Identification. A powered emergency ventilator is a demand valve or inhalator...

2011-04-01

260

46 CFR 72.15-15 - Ventilation for closed spaces.  

Code of Federal Regulations, 2010 CFR

...ventilated. Means shall be provided to close off all vents and ventilators. (b) Means shall be provided for stopping all fans...machinery and cargo spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings...

2010-10-01

261

21 CFR 868.5925 - Powered emergency ventilator.  

...2014-04-01 false Powered emergency ventilator. 868.5925 Section 868.5925...Devices § 868.5925 Powered emergency ventilator. (a) Identification. A powered emergency ventilator is a demand valve or inhalator...

2014-04-01

262

46 CFR 72.15-15 - Ventilation for closed spaces.  

Code of Federal Regulations, 2011 CFR

...ventilated. Means shall be provided to close off all vents and ventilators. (b) Means shall be provided for stopping all fans...machinery and cargo spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings...

2011-10-01

263

21 CFR 868.5935 - External negative pressure ventilator.  

Code of Federal Regulations, 2010 CFR

...false External negative pressure ventilator. 868.5935 Section 868.5935...5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung,...

2010-04-01

264

21 CFR 868.5935 - External negative pressure ventilator.  

Code of Federal Regulations, 2012 CFR

...false External negative pressure ventilator. 868.5935 Section 868.5935...5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung,...

2012-04-01

265

21 CFR 868.5925 - Powered emergency ventilator.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Powered emergency ventilator. 868.5925 Section 868.5925...Devices § 868.5925 Powered emergency ventilator. (a) Identification. A powered emergency ventilator is a demand valve or inhalator...

2010-04-01

266

46 CFR 72.15-15 - Ventilation for closed spaces.  

Code of Federal Regulations, 2013 CFR

...ventilated. Means shall be provided to close off all vents and ventilators. (b) Means shall be provided for stopping all fans...machinery and cargo spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings...

2013-10-01

267

46 CFR 190.15-10 - Ventilation for closed spaces.  

...ventilated. Means shall be provided to close off all vents and ventilators. (b) Means shall be provided for stopping all fans...storerooms, and machinery spaces and for closing all doorways, ventilators, and annular spaces around funnels and other openings...

2014-10-01

268

21 CFR 868.5935 - External negative pressure ventilator.  

Code of Federal Regulations, 2013 CFR

...false External negative pressure ventilator. 868.5935 Section 868.5935...5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung,...

2013-04-01

269

HVAC EFFICIENCY BUSINESS CASE DEMAND CONTROL KITCHEN VENTILATION  

E-print Network

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

California at Davis, University of

270

21 CFR 868.5955 - Intermittent mandatory ventilation attachment.  

Code of Federal Regulations, 2010 CFR

... (a) Identification. An intermittent mandatory ventilation (IMV) attachment is a device attached to a mechanical ventilator that allows spontaneous breathing by a patient while providing mechanical ventilation at a preset rate. (b)...

2010-04-01

271

49 CFR 192.173 - Compressor stations: Ventilation.  

Code of Federal Regulations, 2010 CFR

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

2010-10-01

272

46 CFR 108.181 - Ventilation for enclosed spaces.  

Code of Federal Regulations, 2010 CFR

...SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Ventilation...means to close each vent or ventilating system. (c) Each fan in a ventilating system must have remote controls...

2010-10-01

273

46 CFR 108.181 - Ventilation for enclosed spaces.  

Code of Federal Regulations, 2012 CFR

...SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Ventilation...means to close each vent or ventilating system. (c) Each fan in a ventilating system must have remote controls...

2012-10-01

274

46 CFR 108.181 - Ventilation for enclosed spaces.  

Code of Federal Regulations, 2011 CFR

...SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Ventilation...means to close each vent or ventilating system. (c) Each fan in a ventilating system must have remote controls...

2011-10-01

275

46 CFR 127.260 - Ventilation for accommodations.  

Code of Federal Regulations, 2011 CFR

...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...

2011-10-01

276

24 CFR 3280.103 - Light and ventilation.  

... 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...

2014-04-01

277

21 CFR 888.4230 - Cement ventilation tube.  

Code of Federal Regulations, 2012 CFR

...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...

2012-04-01

278

21 CFR 888.4230 - Cement ventilation tube.  

Code of Federal Regulations, 2013 CFR

...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...

2013-04-01

279

46 CFR 127.260 - Ventilation for accommodations.  

Code of Federal Regulations, 2013 CFR

...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...

2013-10-01

280

14 CFR 27.1187 - Ventilation and drainage.  

...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....

2014-01-01

281

46 CFR 153.316 - Special cargo pumproom ventilation rate.  

Code of Federal Regulations, 2013 CFR

...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...

2013-10-01

282

46 CFR 127.260 - Ventilation for accommodations.  

Code of Federal Regulations, 2012 CFR

...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...

2012-10-01

283

46 CFR 111.103-3 - Machinery space ventilation.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop...

2011-10-01

284

46 CFR 154.1200 - Mechanical ventilation system: General.  

...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...

2014-10-01

285

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

Code of Federal Regulations, 2013 CFR

...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...

2013-10-01

286

46 CFR 111.103-3 - Machinery space ventilation.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop...

2013-10-01

287

46 CFR 153.316 - Special cargo pumproom ventilation rate.  

Code of Federal Regulations, 2011 CFR

...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...

2011-10-01

288

46 CFR 153.316 - Special cargo pumproom ventilation rate.  

...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...

2014-10-01

289

46 CFR 153.316 - Special cargo pumproom ventilation rate.  

Code of Federal Regulations, 2010 CFR

...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...

2010-10-01

290

24 CFR 3280.103 - Light and ventilation.  

Code of Federal Regulations, 2011 CFR

... 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...

2011-04-01

291

24 CFR 3280.103 - Light and ventilation.  

Code of Federal Regulations, 2012 CFR

... 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...

2012-04-01

292

24 CFR 3280.103 - Light and ventilation.  

Code of Federal Regulations, 2013 CFR

... 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...

2013-04-01

293

14 CFR 27.1187 - Ventilation and drainage.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 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....

2013-01-01

294

21 CFR 888.4230 - Cement ventilation tube.  

...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...

2014-04-01

295

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

Code of Federal Regulations, 2011 CFR

...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...

2011-10-01

296

46 CFR 153.316 - Special cargo pumproom ventilation rate.  

Code of Federal Regulations, 2012 CFR

...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...

2012-10-01

297

46 CFR 127.260 - Ventilation for accommodations.  

Code of Federal Regulations, 2010 CFR

...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...

2010-10-01

298

46 CFR 58.01-45 - Machinery space, ventilation.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Machinery space, ventilation. 58.01-45 Section 58.01-45 Shipping COAST...General Requirements § 58.01-45 Machinery space, ventilation. Each machinery space must be ventilated to...

2011-10-01

299

46 CFR 185.352 - Ventilation of gasoline machinery spaces.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Ventilation of gasoline machinery spaces...Operating Requirements § 185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space,...

2011-10-01

300

21 CFR 888.4230 - Cement ventilation tube.  

Code of Federal Regulations, 2010 CFR

...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...

2010-04-01

301

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

Code of Federal Regulations, 2012 CFR

...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...

2012-10-01

302

46 CFR 154.1200 - Mechanical ventilation system: General.  

Code of Federal Regulations, 2012 CFR

...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...

2012-10-01

303

46 CFR 111.103-3 - Machinery space ventilation.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop...

2012-10-01

304

21 CFR 888.4230 - Cement ventilation tube.  

Code of Federal Regulations, 2011 CFR

...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...

2011-04-01

305

46 CFR 154.1200 - Mechanical ventilation system: General.  

Code of Federal Regulations, 2013 CFR

...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...

2013-10-01

306

46 CFR 185.352 - Ventilation of gasoline machinery spaces.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Ventilation of gasoline machinery spaces...Operating Requirements § 185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space,...

2010-10-01

307

14 CFR 27.1187 - Ventilation and drainage.  

Code of Federal Regulations, 2010 CFR

...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....

2010-01-01

308

46 CFR 185.352 - Ventilation of gasoline machinery spaces.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Ventilation of gasoline machinery spaces...Operating Requirements § 185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space,...

2012-10-01

309

46 CFR 185.352 - Ventilation of gasoline machinery spaces.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Ventilation of gasoline machinery spaces...Operating Requirements § 185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space,...

2013-10-01

310

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

NASA Technical Reports Server (NTRS)

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.

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

1986-01-01

311

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

DOEpatents

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.

Corey, John A. (Melrose, NY)

1990-01-01

312

Modeling results of the high temperature pressure-controlled atomization process (PCAP)  

SciTech Connect

The Pressure-Controlled Atomization Process (PCAP) is a thermal spray process that atomizes liquid metals in the flow of a converging-diverging nozzle. The subsonic/transonic/supersonic two-phase gas (with droplets) flows through a nozzle and subsequent subsonic free jet flow from the nozzle to the sprayed surface, provides a particular method used in spray forming/coating technology. In this study, a quasi-one-dimensional model is used to simulate the entire converging-diverging nozzle flow field (with particle injection at the throat) and the plume (free jet) region. The basic numerical technique and computer model solve the steady gas field equations through a conservative variable approach and treat the droplet phase in a Lagrangian manner with full aerodynamic and energetic coupling between the droplets and the transport gas handled via source terms. The liquid metal injection process is also coupled to the throat gas dynamics to achieve a more realistic simulation of the physics. The results from new nozzle designs, high temperature materials, and different gas flows are presented in this paper.

Lee, Y.M. [MSE, Inc., Butte, MT (United States)

1994-12-31

313

JOURNAL OF LATEX CLASS FILES, VOL. 1, NO. 11, NOVEMBER 2002 1 Design of a pressure control system with dead  

E-print Network

. The control law is tested in practice. Index Terms-- Dead zone, time varying delay, pressure control for agricultural equipment where parts need to be reliable and cheap. Dead bands or zones are also encountered in, for example, robots and machine tools [4], [5], [7], hydraulic and pneumatic actuators [9], [6], servo systems

Paris-Sud XI, Université de

314

Commissioning Ventilated Containment Systems in the Laboratory  

SciTech Connect

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.

Not Available

2008-08-01

315

Characterization and measurement of ventilator performance  

NASA Astrophysics Data System (ADS)

The work of the ISO in drawing up ventilator norms is reviewed, and the scientific and technical difficulties encountered when investigating ventilators are summarized. Difficulties arise from the many forms of energy transfered to the fluid, the diversity of gases used, compressibility effects, the wide variety of equipment size and performance, the different functions required, and the heterogeneity of test methods.

Judetlelacombe, A.

316

Infiltration in ASHRAE's Residential Ventilation Standards  

SciTech Connect

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.

Sherman, Max

2008-10-01

317

Clinical review: Long-term noninvasive ventilation  

Microsoft Academic Search

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

Dominique Robert; Laurent Argaud

2007-01-01

318

Alternative ventilation strategies in cardiopulmonary resuscitation  

Microsoft Academic Search

The introduction of the 2000 Guidelines for Cardiopulmonary Resuscitation emphasizes a new, evidence-based approach to the science of ventilation during cardiopulmonary resuscitation (CPR). New laboratory and clinical science underemphasizes the role of ventilation immediately after a dysrhythmic cardiac arrest (arrest primarily resulting from a cardiovascular event, such as ventricular defibrillation or asystole). However, the classic airway patency, breathing, and circulation

Andrea Gabrielli; A. Joseph Layon; Volker Wenzel; Volker Dorges; Ahamed H. Idris

2002-01-01

319

Apparatus for ventilating an enclosed area  

Microsoft Academic Search

This patent describes an apparatus for attachment to a vent tube for ventilating an enclosed area comprising; a tube adaptor for mounting the ventilation apparatus on the vent tube; rotatable hub means secured to and coaxial with the tube adaptor; a substantially hemispherical domelike member rotatably secured to the hub means above the tube adaptor; internal exhaust fan blade means

Schad

1987-01-01

320

Preoperational test report, primary ventilation system  

SciTech Connect

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.

Clifton, F.T.

1997-11-04

321

Implementation of a Hybrid Controller for Ventilation Control Using Soft Computing  

SciTech Connect

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

Craig G. Rieger; D. Subbaram Naidu

2005-06-01

322

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

NASA Astrophysics Data System (ADS)

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.

Dawidowicz, Karol

2014-12-01

323

Genetic Characterisation of Malawian Pneumococci Prior to the Roll-Out of the PCV13 Vaccine Using a High-Throughput Whole Genome Sequencing Approach  

PubMed Central

Background Malawi commenced the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) into the routine infant immunisation schedule in November 2011. Here we have tested the utility of high throughput whole genome sequencing to provide a high-resolution view of pre-vaccine pneumococcal epidemiology and population evolutionary trends to predict potential future change in population structure post introduction. Methods One hundred and twenty seven (127) archived pneumococcal isolates from randomly selected adults and children presenting to the Queen Elizabeth Central Hospital, Blantyre, Malawi underwent whole genome sequencing. Results The pneumococcal population was dominated by serotype 1 (20.5% of invasive isolates) prior to vaccine introduction. PCV13 is likely to protect against 62.9% of all circulating invasive pneumococci (78.3% in under-5-year-olds). Several Pneumococcal Molecular Epidemiology Network (PMEN) clones are now in circulation in Malawi which were previously undetected but the pandemic multidrug resistant PMEN1 lineage was not identified. Genome analysis identified a number of novel sequence types and serotype switching. Conclusions High throughput genome sequencing is now feasible and has the capacity to simultaneously elucidate serotype, sequence type and as well as detailed genetic information. It enables population level characterization, providing a detailed picture of population structure and genome evolution relevant to disease control. Post-vaccine introduction surveillance supported by genome sequencing is essential to providing a comprehensive picture of the impact of PCV13 on pneumococcal population structure and informing future public health interventions. PMID:22970189

Everett, Dean B.; Cornick, Jennifer; Denis, Brigitte; Chewapreecha, Claire; Croucher, Nicholas; Harris, Simon; Parkhill, Julian; Gordon, Stephen; Carrol, Enitan D.; French, Neil; Heyderman, Robert S.; Bentley, Stephen D.

2012-01-01

324

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

PubMed Central

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

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

2012-01-01

325

Advanced pressure control in time division multiplexed (TDM) plasma etch processes  

NASA Astrophysics Data System (ADS)

Time division multiplexed (TDM) plasma etch processes have been widely applied to MEMS device manufacturing due to the capability of defining high aspect ratio features at high etch rates and mask selectivity. To etch anisotropic features using F-based chemistry, a TDM process cyclically alternates between etch and passivation steps, which are normally carried out with different gases introduced into a reaction chamber at different flow rates, and during which chamber pressures are maintained at different levels. Conventional process control methods often result in chamber pressure overshoot and/or undershoot, slow pressure response times, and long-term pressure drifts. These are undesirable effects in manufacturing MEMS devices due to the requirements on process stability, reliability and repeatability. At Unaxis USA Inc., a proprietary control technique has been developed for the TDM etch processes to better control chamber pressures and improve process stability. Controls over the movement of a throttle valve are realized through a combination of pre-positioning the valve and regulating it with the proportional, integral and derivative (PID) function mechanisms. Using this technique, we have demonstrated in fast TDM processes that pressure overshoot and undershoot are significantly suppressed, pressure response times are improved, and long-term pressure drifts are eliminated. To this end, this new control technique has been successfully tested in processes where the etch/passivation process steps are alternating at frequencies up to 1 Hz. Applications of this advanced technique in deep silicon etching have demonstrated improved etch performance. As a result, this advanced pressure control technique enables the TDM dry etching technologies for MEMS devices manufacturing to become markedly more reliable and stable.

Lai, Shouliang; Westerman, Russ; Johnson, Dave; Nolan, John J.

2004-01-01

326

Position paper - primary ventilation system configuration  

SciTech Connect

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.

Dalpiaz, E.L.

1994-06-01

327

Preoperational test report, primary ventilation condensate system  

SciTech Connect

Preoperational test report for Primary Ventilation Condensate System, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides a collection point for condensate generated by the W-030 primary vent offgas cooling system serving tanks AYIOI, AY102, AZIOI, AZI02. The system is located inside a shielded ventilation equipment cell and consists of a condensate seal pot, sampling features, a drain line to existing Catch Tank 241-AZ-151, and a cell sump jet pump. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

Clifton, F.T.

1997-01-29

328

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

329

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

330

Round table March 2005, Brussels The ventilator of tomorrow  

E-print Network

Round table ­ March 2005, Brussels The ventilator of tomorrow Laurent Brochard, MD, Michel Dojat (France) Tél. 01.49.81.25.45 e-mail : laurent.brochard@hmn.aphp.fr #12;The ventilator of our dreams does this ventilator. Technology is very present in the intensive care unit. The field of mechanical ventilation has

Dojat, Michel

331

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 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

Lewis, Mark

332

30 CFR 77.1911 - Ventilation of slopes and shafts.  

Code of Federal Regulations, 2011 CFR

...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....

2011-07-01

333

30 CFR 77.1911 - Ventilation of slopes and shafts.  

Code of Federal Regulations, 2013 CFR

...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....

2013-07-01

334

30 CFR 77.1911 - Ventilation of slopes and shafts.  

Code of Federal Regulations, 2012 CFR

...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....

2012-07-01

335

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

SciTech Connect

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)

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

336

Global temperature field simulation of the vapour pressure controlled Czochralski (VCZ) growth of 3?–4? gallium arsenide crystals  

Microsoft Academic Search

The vapour pressure controlled Czochralski (VCZ) method belongs to the new methods to provide low-gradient temperature fields during the growth of III–V crystals. For the first time a global two-dimensional model of the VCZ growth of 3? and 4? GaAs crystals is presented. The finite volume code CrysVUN++ was used to simulate heat transfer taking into account conduction and radiation

K. Bottcher; P Rudolph; M Neubert; M Kurz; A Pusztai; G Müller

1999-01-01

337

Inhaled antibiotic therapy for ventilator-associated tracheobronchitis and ventilator-associated pneumonia: an Update  

Microsoft Academic Search

Ventilator-associated pneumonia (VAP) remains a leading cause of morbidity and mortality in mechanically-ventilated patients\\u000a in the Intensive Care Unit (ICU). Ventilator-associated tracheobronchitis (VAT) was previously believed to be an intermediate\\u000a stage between colonization of the lower respiratory tract and VAP. More recent data, however, suggest that VAT may be a separate\\u000a entity that increases morbidity and mortality, independently of the

Tareq Abu-Salah; Rajiv Dhand

338

Respiratory care year in review 2010: part 2. Invasive mechanical ventilation, noninvasive ventilation, pediatric mechanical ventilation, aerosol therapy.  

PubMed

The purpose of this paper is to review the recent literature related to invasive mechanical ventilation, NIV, pediatric mechanical ventilation, and aerosol therapy. Topics covered related to invasive mechanical ventilation topics include the role of PEEP in providing lung protection during mechanical ventilation, unconventional modes for severe hypoxemia, and strategies to improve patient-ventilator interactions. Topics covered related to NIV include real-life NIV use, NIV and extubation failure, and NIV and pandemics. For pediatric mechanical ventilation, the topics addressed are NIV, invasive respiratory support, and inhaled nitric oxide. Topics covered related to aerosol therapy include short-acting ?-adrenergic agents, long-acting ?-adrenergic agents, long-acting antimuscarinic agents, inhaled corticosteroid therapy, phosphodiesterase type 4 (PDE4) inhibitors, long-acting ?-adrenergic plus inhaled corticosteroid, long-acting antimuscarinic plus inhaled corticosteroid, nebulized hypertonic saline, inhaled mannitol, and inhaled antibiotic therapy. These topics were chosen and reviewed in a manner that is most likely to have interest to the readers of Respiratory Care. PMID:21669105

Macintyre, Neil R; Nava, Stefano; Diblasi, Robert M; Restrepo, Ruben D; Hess, Dean R

2011-05-01

339

MR-compatible ventilator for small animals: computer-controlled ventilation for proton and noble gas imaging  

E-print Network

MR-compatible ventilator for small animals: computer-controlled ventilation for proton and noble; accepted 28 April 2000 Abstract We describe an MR-compatible ventilator that is computer controlled, and to support delivery of gas anesthesia and experimental inhalational gases. A key feature of this ventilator

340

Aspekter som avgör anestesisjuksköterskans val av peroperativ ventilation vid bukkirurgi, volym eller tryckkontrollerad ventilation?.  

E-print Network

?? Bakgrund. Enligt den nya kompetensbeskrivningen för anestesisjuksköterskor framgår bland annat att anestesisjuksköterskan ska ha kompetens att övervaka och följa upp ventilation och cirkulation hos… (more)

Chowdhury, Patrik

2009-01-01

341

Analysis to ventilation effectiveness in subway fire environment  

Microsoft Academic Search

When longitudinal ventilation is activated in subway station platform fire, smoke-control effectiveness depends on ventilation effectiveness. With the ventilation motion analyzed, its time at staircase is decreased and ventilation effectiveness gets better all along platform. In case of 30 MW fire with 80 m3\\/s smoke volume flow rate, longitudinal ventilation of bigger than 1.5 m\\/s freshens platform all around for

Wen-Zhong Wu; Shi-Jun You

2009-01-01

342

46 CFR 98.25-75 - Ventilation.  

Code of Federal Regulations, 2012 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-75 Ventilation. (a) All enclosed spaces containing cargo tanks fitted with bottom...

2012-10-01

343

46 CFR 98.25-75 - Ventilation.  

Code of Federal Regulations, 2011 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-75 Ventilation. (a) All enclosed spaces containing cargo tanks fitted with bottom...

2011-10-01

344

46 CFR 98.25-75 - Ventilation.  

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-75 Ventilation. (a) All enclosed spaces containing cargo tanks fitted with bottom...

2014-10-01

345

46 CFR 98.25-75 - Ventilation.  

Code of Federal Regulations, 2013 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-75 Ventilation. (a) All enclosed spaces containing cargo tanks fitted with bottom...

2013-10-01

346

46 CFR 98.25-75 - Ventilation.  

Code of Federal Regulations, 2010 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-75 Ventilation. (a) All enclosed spaces containing cargo tanks fitted with bottom...

2010-10-01

347

46 CFR 111.15-10 - Ventilation.  

...ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111...General. Each room, locker, and box for storage batteries must be arranged or ventilated to prevent...

2014-10-01

348

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 ...

349

Midlevel Ventilation's Constraint on Tropical Cyclone Intensity  

E-print Network

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 ...

Tang, Brian Hong-An

350

Tunnel ventilation effectiveness in fire scenarios   

E-print Network

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...

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

2010-01-01

351

14 CFR 23.831 - Ventilation.  

Code of Federal Regulations, 2012 CFR

...sufficient amount of uncontaminated air to enable the flight crew members to perform their duties without undue discomfort or fatigue. For normal operating conditions, the ventilation system must be designed to provide each occupant with at least...

2012-01-01

352

46 CFR 194.15-5 - Ventilation.  

Code of Federal Regulations, 2010 CFR

...HANDLING, USE, AND CONTROL OF EXPLOSIVES AND OTHER HAZARDOUS MATERIALS Chemistry Laboratory and Scientific Laboratory § 194.15-5 Ventilation. (a) Operations, reactions or experiments which produce toxic, noxious or...

2010-10-01

353

A Ventilation Index for Tropical Cyclones  

E-print Network

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 ...

Tang, Brian

354

30 CFR 57.8520 - Ventilation plan.  

Code of Federal Regulations, 2010 CFR

...HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground...principal air flows; (2) Locations of seals used to isolate abandoned workings;...

2010-07-01

355

30 CFR 57.8520 - Ventilation plan.  

Code of Federal Regulations, 2011 CFR

...HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground...principal air flows; (2) Locations of seals used to isolate abandoned workings;...

2011-07-01

356

30 CFR 57.8520 - Ventilation plan.  

...HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground...principal air flows; (2) Locations of seals used to isolate abandoned workings;...

2014-07-01

357

30 CFR 57.8520 - Ventilation plan.  

Code of Federal Regulations, 2013 CFR

...HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground...principal air flows; (2) Locations of seals used to isolate abandoned workings;...

2013-07-01

358

30 CFR 57.8520 - Ventilation plan.  

Code of Federal Regulations, 2012 CFR

...HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ventilation Underground...principal air flows; (2) Locations of seals used to isolate abandoned workings;...

2012-07-01

359

Midlevel ventilation's constraint on tropical cyclone intensity  

E-print Network

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 ...

Tang, Brian Hong-An

2010-01-01

360

Waste tank ventilation system waste material accumulations  

SciTech Connect

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

Van Vleet, R.J., Westinghouse Hanford

1996-08-06

361

Scale model studies of displacement ventilation  

E-print Network

Displacement ventilation is an air conditioning method that provides conditioned air to indoor environments with the goal to improve air quality while reducing energy consumption. This study investigates the performance ...

Okutan, Galip Mehmet

1995-01-01

362

Sensor-based demand controlled ventilation  

SciTech Connect

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.

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

1997-07-01

363

Recovering Energy From Ventilation and Process Airstreams  

E-print Network

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...

Cheney, W. A.

364

Blood pressure control and antihypertensive pharmacotherapy patterns in a hypertensive population of Eastern Central Region of Portugal  

PubMed Central

Background Interventions to improve blood pressure control in hypertension have had limited success in clinical practice despite evidence of cardiovascular disease prevention in randomised controlled trials. The objectives of this study were to evaluate blood pressure control and antihypertensive pharmacotherapy patterns in a population of Eastern Central Region of Portugal, attending a hospital outpatient clinic (ambulatory setting) for routine follow-up. Methods Medical data of all patients that attended at least two medical appointments of hypertension/dyslipidemia in a university hospital over a one and a half year period (from January 2008 to June 2009) were retrospectively analysed. Demographic variables, clinical data and blood pressure values of hypertensive patients included in the study, as well as prescribing metrics were examined on a descriptive basis and expressed as the mean ± SD, frequency and percentages. Student's test and Mann-Whitney rank sum test were used to compare continuous variables and ?2 test and Fisher exact probability test were used to test for differences between categorical variables. Results In all, 37% of hypertensive patients (n = 76) had their blood pressure controlled according to international guidelines. About 45.5% of patients with a target blood pressure <140/90 mmHg (n = 156) were controlled, whereas in patients with diabetes or chronic kidney disease (n = 49) the corresponding figure was only 10.2% (P < 0.001). Among patients initiating hypertension/dyslipidemia consultation within the study period 32.1% had stage 2 hypertension in the first appointment, but this figure decreased to 3.6% in the last consultation (P = 0.012). Thiazide-type diuretics were the most prescribed antihypertensive drugs (67%) followed by angiotensin receptor blockers (60%) and beta-blockers (43%). About 95.9% patients with comorbid diabetes were treated with an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Conclusions Clinically important blood pressure decreases can be achieved soon after hypertension medical appointment initiation. However, many hypertensive patients prescribed with antihypertensive therapy fail to achieve blood pressure control in clinical practice, this control being worse among patients with diabetes or chronic kidney disease. As pharmacotherapy patterns seem to coincide with international guidelines, further research is needed to identify the causes of poor blood pressure control. PMID:21192829

2010-01-01

365

Engineering work plan and design basis for 241-SY ventilation improvements  

SciTech Connect

There are three tanks in the 241-SY tank farm. Tank 241-SY101 and 241-SY-103 are flammable gas watch list tanks. Tank 241-SY-102 is included in the ventilation improvement process in an effort to further control air flow in the tank farm. This tank farm has only one outlet ventilation port for all three tanks. Flammable gas is released (may be steady and/or periodic) from the waste in the primary tank vapor space. The gas is removed from the tank by an active ventilation system. However, maintaining consistent measurable flow through the tank can be problematic due to the poor control capabilities of existing equipment. Low flow through the tank could allow flammable gas to build up in the tank and possibly exceed the lower flammability limit (LFL), prevent the most rapid removal of flammable gas from the tank after a sudden gas release, and/or cause high vacuum alarms to sound. Using the inlet and outlet down stream butterfly valves performs the current method of controlling flow in tank farm 241-SY. A filter station is installed on the inlet of each tank, but controlling air flow with its 12 inch butterfly valve is difficult. There is also in-leakage through pump and valve pits. Butterfly valves on the downstream side of each tank could also be used to control air flow. However, their large size and the relatively low air velocity make this control method also ineffective. The proposed method of optimizing tank air flow and pressure control capability is to install an air flow controller on the inlet of each existing filter station in SY farm, and seal as best as practical all other air leakage paths. Such air flow controllers have been installed on 241-AN and 241-AW tanks (see drawing H-2-85647).

Andersen, J.A.

1997-05-19

366

Home mechanical ventilation for amyotrophic lateral sclerosis: nasal compared to tracheostomy-intermittent positive pressure ventilation  

Microsoft Academic Search

People with amyotrophic lateral sclerosis (ALS) usually die from respiratory failure unless they use mechanical ventilation (MV). Many die of respiratory failure without being adequately informed about the available options, such as MV, that can provide symptomatic relief and prolong survival. The traditional method of MV used for persons with ALS has been tracheostomy-intermittent positive pressure ventilation (IPPV). However, the

Pamela A. Cazzolli; Edward A. Oppenheimer

1996-01-01

367

Predictors to parental knowledge about childhood immunisation/EPI vaccines in two health districts in Cameroon prior to the introduction of 13-valent Pneumococcal Conjugate Vaccines (PCV-13)  

PubMed Central

Introduction Pneumonia is vaccine-preventable, but the increasing death toll resulting from the disease in Sub-Saharan Africa is alarming. Several factors account for vaccine failing to reach every child, besides incomplete vaccine coverage. Most of these include the perceptions of parents/guardians and healthcare providers. Previous studies on the introduction of new vaccines have focused on experimental trials, coverage figures and vaccine efficacy in developed countries. Little is known on the factors which may hinder the implementation process despite the huge challenges this may encounter in developing countries. This study described the knowledge, attitude and practices (KAP) of parents/guardians on pneumonia and immunisations/EPI vaccines; identify predictive parental socio-economic/demographic characteristics that of good knowledge on pneumonia infections, routine EPI vaccines and the PCV-13. Finally, the study described health center personnel perceptions about immunisations. Methods The WHO's immunisation coverage cluster survey design was used, involving parents/guardians (n = 205) of children aged 0-59 months and health centre personnel (n = 13) directly concerned with vaccination activities between July-September 2010 in two health districts in Yaounde, Cameroon. Descriptive statistics and multivariate logistic models were used to analyse the parental/guardian data while the health personnel data was only analysed descriptively using SPSS version 17.0. Results Only 19% of the parents/guardians were aware of the availability of the PCV-13. Logistic modelling identified important associations between parental socio-economic/demographic factors and good knowledge on pneumonia disease burden and prevention. Conclusion According to parents/guardians a short and clear message on the dangers of pneumonia and the need for prevention provided to parents/guardians during sensitisation/out-reach campaigns and use of social network avenues would be primordial, if the PCV-13 is to reach every child. PMID:25396013

Libwea, John Njuma; Kobela, Marie; Ollgren, Jukka; Emah, Irene; Tchio, Robert; Nohynek, Hanna

2014-01-01

368

Episodic ventilation lowers the efficiency of pulmonary CO2 excretion.  

PubMed

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

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

2013-11-01

369

Ventilation efficiencies of a desk-edge-mounted task ventilation system  

SciTech Connect

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.

Faulkner, David; Fisk, William J.; Sullivan, Douglas P.; Lee, Seung Min

2002-03-01

370

Hydrostatic Hyperbaric Chamber Ventilation System  

NASA Technical Reports Server (NTRS)

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.

Sarguisingh, Miriam J.

2012-01-01

371

Hydrostatic Hyperbaric Chamber Ventilation System  

NASA Technical Reports Server (NTRS)

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.

Sargusingh, Miriam M.

2011-01-01

372

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

PubMed

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

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

373

WASTE HANDLING BUILDING VENTILATION SYSTEM DESCRIPTION DOCUMENT  

SciTech Connect

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.

P.A. Kumar

2000-06-21

374

WASTE TREATMENT BUILDING VENTILATION SYSTEM DESCRIPTION DOCUMENT  

SciTech Connect

The Waste Treatment 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 Treatment Building (WTB). 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 personnel comfort and equipment operation, the contamination confinement area ventilation system directs potentially contaminated air away from personnel in the WTB and confines the contamination within high-efficiency particulate air (HEPA) filtration units. The contamination confinement area ventilation system creates airflow paths and pressure zones to minimize the potential for spreading contamination with 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 WTB. The Waste Treatment 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 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 Treatment Building Ventilation System interfaces with the Waste Treatment Building System by being located in the WTB, and by maintaining specific pressure, temperature, and humidity environments within the building. The system also depends on the WTB for normal electric power supply and the required supply of water for heating, cooling, and humidification. Interface with the Waste Treatment Building System includes the WTB fire protection subsystem for detection of fire and smoke. The Waste Treatment Building Ventilation System interfaces with the Site Radiological Monitoring System for continuous monitoring of the exhaust air and key areas within the WTB, the Monitored Geologic Repository Operations Monitoring and Control System for monitoring and control of system operations, and the Site Generated Radiological Waste Handling System and Site Generated Hazardous, Non-Hazardous & Sanitary Waste Disposal System for routing of pretreated toxic, corrosive, and radiologically contaminated effluent from process equipment to the HEPA filter exhaust ductwork and air-cleaning unit.

P.A. Kumar

2000-06-22

375

Benchmarking mechanical ventilation services in teaching hospitals.  

PubMed

The purpose of this investigation was to examine the technical efficiency of mechanical ventilation nonsurgery (DRG 475) among University Hospital Consortium (UHC) hospitals that consists of volunteer, teaching hospitals across the nation. The data for this study was retrieved from the 1997 UHC database that includes charge and discharge information for 69 hospitals. Data on 7961 patients classified with mechanical ventilation were aggregated to the hospital level. We retained data from a total of 62 hospitals, the other seven hospitals had missing data. The research questions were (1) Do UHC hospitals differ significantly in their efficiencies in the treatment of mechanically ventilated patients? (2) What inputs and outputs contribute most to the inefficiencies associated with mechanical ventilation? Of the 62 hospitals analyzed using data envelopment analysis technique, 10 were considered efficient and 52 were inefficient as compared to their benchmark peers. Efficient and inefficient hospitals did significantly differ between the transferred output variable and between the respiratory, laboratory, and radiology input variables. All inputs demonstrated excessive resource utilization among inefficient hospitals as compared to efficient hospitals. A total reduction of about $19 million dollars in ancillary services would need to occur for inefficient hospitals to approach the frontier of efficient hospitals. This study demonstrates that mechanical ventilation is costly, yet the specified ancillary services are capable of being reduced yielding technical efficiency as demonstrated by 10 efficient hospitals. PMID:12018609

O'Neal, Pamela V; Ozcan, Yasar A; Ma, Yanqiang

2002-06-01

376

Design Feature 7: Continuous Preclosure Ventilation  

SciTech Connect

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.

A.T. Watkins

1999-06-22

377

Efficacy of intermittent ventilation for providing acceptable indoor air quality  

SciTech Connect

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.

Sherman, M.H.

2004-10-01

378

30 CFR 57.8531 - Construction and maintenance of ventilation doors.  

Code of Federal Regulations, 2013 CFR

...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...

2013-07-01

379

30 CFR 57.8531 - Construction and maintenance of ventilation doors.  

Code of Federal Regulations, 2010 CFR

...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...

2010-07-01

380

30 CFR 57.8531 - Construction and maintenance of ventilation doors.  

Code of Federal Regulations, 2012 CFR

...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...

2012-07-01

381

30 CFR 57.8531 - Construction and maintenance of ventilation doors.  

Code of Federal Regulations, 2011 CFR

...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...

2011-07-01

382

30 CFR 57.8531 - Construction and maintenance of ventilation doors.  

...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...

2014-07-01

383

MODELING VENTILATION SYSTEM RESPONSE TO FIRE  

SciTech Connect

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.

Coutts, D

2007-04-17

384

Regenerative Blower for EVA Suit Ventilation Fan  

NASA Technical Reports Server (NTRS)

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.

Paul, Heather; Izenson, Mike; Chen, Weibo

2008-01-01

385

A novel osmotic pressure control fed-batch fermentation strategy for improvement of erythritol production by Yarrowia lipolytica from glycerol.  

PubMed

The effect of osmotic pressure on erythritol and mannitol production by an osmophilic yeast strain of Yarrowia lipolytica CICC 1675 using glycerol as the sole carbon source was investigated. Appropriately high osmotic pressure was found to enhance erythritol production and inhibit mannitol formation. A novel two-stage osmotic pressure control fed-batch strategy based on the kinetic analysis was developed for higher erythritol yield and productivity. During the first 96 h, the osmotic pressure was maintained at 4.25 osmol/kg by feeding glycerol to reduce the inhibition of cell growth. After 132 h, the osmotic pressure was controlled at 4.94 osmol/kg to maintain a high dp(ery)/dt. Maximum erythritol yield of 194.3g/L was obtained with 0.95 g/L/h productivity, which were 25.7% and 2.2%, respectively, improvement over the best results in one-stage fed-batch fermentation. This is the first report that a novel osmotic pressure control fed-batch strategy significantly enhanced erythritol production. PMID:24215768

Yang, Li-Bo; Zhan, Xiao-Bei; Zheng, Zhi-Yong; Wu, Jian-Rong; Gao, Min-Jie; Lin, Chi-Chung

2014-01-01

386

46 CFR 108.181 - Ventilation for enclosed spaces.  

Code of Federal Regulations, 2013 CFR

...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...

2013-10-01

387

46 CFR 108.185 - Ventilation for enclosed classified locations.  

...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...

2014-10-01

388

46 CFR 108.185 - Ventilation for enclosed classified locations.  

Code of Federal Regulations, 2010 CFR

...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...

2010-10-01

389

Review: Artifical ventilation with positive end-expiratory pressure (PEEP)  

Microsoft Academic Search

CPPV (continuous positive pressure ventilation) is obviously superior to IPPV (intermittent positive pressure ventilation) for the treatment of patients with acute respiratory insufficiency (ARI) and results within a few minutes in a considerable increase in the oxygen transport.

Dag Berger Stokke

1976-01-01

390

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- ...

391

Study on Influencing Factors of Night Ventilation in Office Rooms  

E-print Network

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...

Wang, Z.; Sun, X.

2006-01-01

392

Energy Saving Guidelines for Portland State University Heating and Ventilation  

E-print Network

Energy Saving Guidelines for Portland State University Heating and Ventilation Conditioned spaces. Building ventilation will be based on actual use of the space, as determined by Academic Schedules, Posted

Caughman, John

393

3. LEPLEY VENTILATOR FROM EAST. STEAM ENGINE CYLINDER AT LEFT, ...  

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

3. LEPLEY VENTILATOR FROM EAST. STEAM ENGINE CYLINDER AT LEFT, AEROVANE FAN HOOD AT RIGHT REAR. - Consolidation Coal Company Mine No. 11, Lepley Ventilator, East side of State Route 936, Midlothian, Allegany County, MD

394

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

395

A scale model study of displacement ventilation with chilled ceilings  

E-print Network

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 ...

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

1995-01-01

396

Design of a Natural Ventilation System in the Dunhuang Museum  

E-print Network

that also meets architectural standards. Natural ventilation design methods are presented in this paper. A natural ventilation system is designed in the DunHuang museum. Thermal dynamic simulation and CFD simulation were analyzed in the exhibition hall...

Zhang, Y.; Guan, W.

2006-01-01

397

Study of natural ventilation in buildings with large eddy simulation  

E-print Network

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 ...

Jiang, Yi, 1972-

2002-01-01

398

12. NEW YORK SIDE, HUDSON RIVER VENTILATION BUILDING IN FOREGROUND; ...  

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

12. NEW YORK SIDE, HUDSON RIVER VENTILATION BUILDING IN FOREGROUND; NEW JERSEY SIDE, HUDSON RIVEN VENTILATION BUILDING IN BACKGROUND - Holland Tunnel, Beneath Hudson River between New York & Jersey City, New York, New York County, NY

399

Indoor Air Quality: Is Increased Ventilation the Answer?  

ERIC Educational Resources Information Center

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)

Hansen, Shirley

1989-01-01

400

30 CFR 57.14213 - Ventilation and shielding for welding.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Ventilation and shielding for welding. 57.14213 Section 57.14213 Mineral Resources...Procedures § 57.14213 Ventilation and shielding for welding. (a) Welding operations shall be shielded when performed at...

2011-07-01

401

30 CFR 57.14213 - Ventilation and shielding for welding.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Ventilation and shielding for welding. 57.14213 Section 57.14213 Mineral Resources...Procedures § 57.14213 Ventilation and shielding for welding. (a) Welding operations shall be shielded when performed at...

2013-07-01

402

30 CFR 56.14213 - Ventilation and shielding for welding.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Ventilation and shielding for welding. 56.14213 Section 56.14213 Mineral Resources...Procedures § 56.14213 Ventilation and shielding for welding. (a) Welding operations shall be shielded when performed at...

2013-07-01

403

30 CFR 56.14213 - Ventilation and shielding for welding.  

...2014-07-01 false Ventilation and shielding for welding. 56.14213 Section 56.14213 Mineral Resources...Procedures § 56.14213 Ventilation and shielding for welding. (a) Welding operations shall be shielded when performed at...

2014-07-01

404

30 CFR 57.14213 - Ventilation and shielding for welding.  

...2014-07-01 false Ventilation and shielding for welding. 57.14213 Section 57.14213 Mineral Resources...Procedures § 57.14213 Ventilation and shielding for welding. (a) Welding operations shall be shielded when performed at...

2014-07-01

405

30 CFR 56.14213 - Ventilation and shielding for welding.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Ventilation and shielding for welding. 56.14213 Section 56.14213 Mineral Resources...Procedures § 56.14213 Ventilation and shielding for welding. (a) Welding operations shall be shielded when performed at...

2011-07-01

406

30 CFR 56.14213 - Ventilation and shielding for welding.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Ventilation and shielding for welding. 56.14213 Section 56.14213 Mineral Resources...Procedures § 56.14213 Ventilation and shielding for welding. (a) Welding operations shall be shielded when performed at...

2012-07-01

407

30 CFR 57.14213 - Ventilation and shielding for welding.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Ventilation and shielding for welding. 57.14213 Section 57.14213 Mineral Resources...Procedures § 57.14213 Ventilation and shielding for welding. (a) Welding operations shall be shielded when performed at...

2012-07-01

408

30 CFR 56.14213 - Ventilation and shielding for welding.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Ventilation and shielding for welding. 56.14213 Section 56.14213 Mineral Resources...Procedures § 56.14213 Ventilation and shielding for welding. (a) Welding operations shall be shielded when performed at...

2010-07-01

409

30 CFR 57.14213 - Ventilation and shielding for welding.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Ventilation and shielding for welding. 57.14213 Section 57.14213 Mineral Resources...Procedures § 57.14213 Ventilation and shielding for welding. (a) Welding operations shall be shielded when performed at...

2010-07-01

410

Intermodule ventilation studies for the Space Station  

NASA Technical Reports Server (NTRS)

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.

Davis, Roy G.; Reuter, James L.

1987-01-01

411

Preoperational test report, recirculation ventilation systems  

SciTech Connect

This represents a preoperational test report for Recirculation Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102 and supports the ability to exhaust air from each tank. Each system consists of a valved piping loop, a fan, condenser, and moisture separator; equipment is located inside each respective tank farm in its own hardened building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

Clifton, F.T.

1997-11-11

412

[Monitoring of patients receiving mechanical ventilation].  

PubMed

Patients undergoing mechanical ventilation are usually treated in the intensive care unit. Monitoring of these patients is challenging for all members of the medical staff. Understanding the aetiology of respiratory failure as well as the pathophysiological principles is essential for appropriate monitoring and treatment. Besides observation of clinical signs, different monitoring methods have become available including invasive and non-invasive diagnostic tools. Furthermore, knowledge about oxygen supply and oxygen consumption as well as respiratory muscle capacities and workload is important. The current article presents an overview of these issues and evaluates different diagnostic tools to monitor ventilator-dependent patients. PMID:25006972

Storre, J H; Dellweg, D

2014-08-01

413

Basics of mechanical ventilation for dogs and cats.  

PubMed

Respiratory failure may occur due to hypoventilation or hypoxemia. Regardless of the cause, emergent anesthesia and intubation, accompanied by positive pressure ventilation, may be necessary and life saving. Long-term mechanical ventilation requires some specialized equipment and knowledge; however, short-term ventilation can be accomplished without the use of an intensive care unit ventilator, and can provide oxygen supplementation and carbon dioxide removal in critical patients. PMID:23747268

Hopper, Kate; Powell, Lisa L

2013-07-01

414

Application of solar-powered ventilator in automobiles  

SciTech Connect

Feasibility of application of solar-powered ventilator in automobile is discussed. The ventilator can effectively prevent the interior temperature of the automobile from rising excessively when the vehicle is soaked in the environment of high solar radiant flux and high ambient temperature. The operating cost of solar-powered ventilator is almost nil. A numerical method developed for determination of the effect of this ventilator on the interior temperature of the automobile is presented and discussed.

Chiou, J.P.

1986-01-01

415

Measurement of continuous distributions of ventilation-perfusion ratios - Theory  

NASA Technical Reports Server (NTRS)

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.

Wagner, P. D.; Saltzman, H. A.; West, J. B.

1974-01-01

416

Patient Safety: Reduce the Risk of Ventilator-Associated Pneumonia  

Microsoft Academic Search

ISSUE: Ventilator-associated pneumonia (VAP) is a common complication in the intensive care unit (ICU) in ventilated patients.PROJECT: To reduce the risk of healthcare-acquired, ventilator-associated pneumonia with nursing practice improvements and a comprehensive oral care program. A multidisciplinary team reviewed infection rates and current patient-care practices of ventilated patients in the ICU. Actions were taken and evaluated during a 6-month period.

R. Hall; N. Simpson

2004-01-01

417

Breathing pattern and cost of ventilation in the american alligator  

Microsoft Academic Search

The energetic cost of pulmonary ventilation is termed the “cost of breathing” and is commonly determined from the change in oxygen uptake with altered ventilation. Previous analyses of lung mechanics predicts increased tidal volume would be more expensive than increased breathing frequency. Existing studies on the oxidative cost of breathing have, however, not addressed breathing pattern. We stimulated ventilation in

Tobias Wang; Stephen J. Warburton

1995-01-01

418

46 CFR 127.250 - Ventilation for enclosed spaces.  

Code of Federal Regulations, 2012 CFR

...ventilated. Means must be provided for closing each vent and ventilator. (b) Means must be provided for stopping each fan in...cargo spaces and for closing, in case of fire, each doorway, ventilator, and annular space around funnels and other openings...

2012-10-01

419

Improved Wireless Performance from Mode Scattering in Ventilation Ducts  

E-print Network

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

Stancil, Daniel D.

420

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

421

46 CFR 171.118 - Automatic ventilators and side ports.  

...2014-10-01 2014-10-01 false Automatic ventilators and side ports. 171.118 Section...Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must not be fitted in the side of...

2014-10-01

422

46 CFR 171.118 - Automatic ventilators and side ports.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Automatic ventilators and side ports. 171.118 Section...Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must not be fitted in the side of...

2011-10-01

423

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

424

Estimating ventilation time scales using overturning stream functions  

E-print Network

Estimating ventilation time scales using overturning stream functions Bijoy Thompson & Jonas 2014 # Springer-Verlag Berlin Heidelberg 2014 Abstract A simple method for estimating ventilation time-enclosed ocean basin ventilated through a narrow strait over a sill, and the result is compared to age estimates

Döös, Kristofer

425

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

...ventilated in a manner suitable for the purpose of the space. (b) A means must be provided to close off all vents and ventilators. (c) Living spaces must be ventilated by a mechanical system unless it can be shown that a natural system...

2014-10-01

426

46 CFR 127.250 - Ventilation for enclosed spaces.  

Code of Federal Regulations, 2013 CFR

...ventilated. Means must be provided for closing each vent and ventilator. (b) Means must be provided for stopping each fan in...cargo spaces and for closing, in case of fire, each doorway, ventilator, and annular space around funnels and other openings...

2013-10-01

427

46 CFR 171.118 - Automatic ventilators and side ports.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Automatic ventilators and side ports. 171.118 Section...Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must not be fitted in the side of...

2010-10-01

428

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

429

46 CFR 92.15-10 - Ventilation for closed spaces.  

Code of Federal Regulations, 2011 CFR

...be provided to close off all vents and ventilators. (b) Means shall be provided...spaces and for closing all doorways, ventilators and annular spaces around funnels and...with a fixed bilge system, vents and ventilators may be omitted from void spaces....

2011-10-01

430

AIR FLOW MODELING IN DEEP WELLS: APPLICATION TO MINING VENTILATION  

E-print Network

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

Paris-Sud XI, Université de

431

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

432

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

Code of Federal Regulations, 2011 CFR

...ventilated in a manner suitable for the purpose of the space. (b) A means must be provided to close off all vents and ventilators. (c) Living spaces must be ventilated by a mechanical system unless it can be shown that a natural system...

2011-10-01

433

"Passive Ventilation in a Simple Structure" Thomas Rogg  

E-print Network

"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

Mountziaris, T. J.

434

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

Code of Federal Regulations, 2010 CFR

...ventilated in a manner suitable for the purpose of the space. (b) A means must be provided to close off all vents and ventilators. (c) Living spaces must be ventilated by a mechanical system unless it can be shown that a natural system...

2010-10-01

435

46 CFR 127.250 - Ventilation for enclosed spaces.  

...ventilated. Means must be provided for closing each vent and ventilator. (b) Means must be provided for stopping each fan in...cargo spaces and for closing, in case of fire, each doorway, ventilator, and annular space around funnels and other openings...

2014-10-01

436

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

Code of Federal Regulations, 2012 CFR

...ventilated in a manner suitable for the purpose of the space. (b) A means must be provided to close off all vents and ventilators. (c) Living spaces must be ventilated by a mechanical system unless it can be shown that a natural system...

2012-10-01

437

Experimental Study of Ventilation Performance in Laboratories with Chemical Spills  

E-print Network

1 Experimental Study of Ventilation Performance in Laboratories with Chemical Spills Mingang Chemical spills occur frequently in laboratories. The current ventilation code for laboratories recommends a ventilation rate of 12 ACH for maintaining a safe laboratory environment. On the other hand, the energy saving

Chen, Qingyan "Yan"

438

46 CFR 171.118 - Automatic ventilators and side ports.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Automatic ventilators and side ports. 171.118 Section...Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must not be fitted in the side of...

2012-10-01

439

46 CFR 127.250 - Ventilation for enclosed spaces.  

Code of Federal Regulations, 2010 CFR

...ventilated. Means must be provided for closing each vent and ventilator. (b) Means must be provided for stopping each fan in...cargo spaces and for closing, in case of fire, each doorway, ventilator, and annular space around funnels and other openings...

2010-10-01

440

46 CFR 127.250 - Ventilation for enclosed spaces.  

Code of Federal Regulations, 2011 CFR

...ventilated. Means must be provided for closing each vent and ventilator. (b) Means must be provided for stopping each fan in...cargo spaces and for closing, in case of fire, each doorway, ventilator, and annular space around funnels and other openings...

2011-10-01

441

46 CFR 92.15-10 - Ventilation for closed spaces.  

Code of Federal Regulations, 2012 CFR

...be provided to close off all vents and ventilators. (b) Means shall be provided...spaces and for closing all doorways, ventilators and annular spaces around funnels and...with a fixed bilge system, vents and ventilators may be omitted from void spaces....

2012-10-01

442

Harms of Unintentional Leaks during Volume Targeted Pressure Support Ventilation  

E-print Network

1 Harms of Unintentional Leaks during Volume Targeted Pressure Support Ventilation Sonia Khirani1 Background: Volume targeted pressure support ventilation (VT-PSV) is a hybrid mode increasingly used. The objective of the study was to determine the ability of home ventilators to maintain the preset minimal VT

Paris-Sud XI, Université de

443

Natural Ventilation Design for Houses in Thailand Chalermwat Tantasavasdia  

E-print Network

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

Chen, Qingyan "Yan"

444

Why We Ventilate J.M. Logue1  

E-print Network

Why We Ventilate J.M. Logue1 , M. H. Sherman, P.N. Price, B.C. Singer Environmental Number 5093E 1 Corresponding author: jmlogue@lbl.gov #12;Logue et al., Why We Ventilate LBNL 5093-E, P.N. Price, M.H. Sherman, B.C. Singer, Why We Ventilate; LBNL-5093E #12;Logue et al., Why We

445

46 CFR 92.15-10 - Ventilation for closed spaces.  

Code of Federal Regulations, 2010 CFR

...be provided to close off all vents and ventilators. (b) Means shall be provided...spaces and for closing all doorways, ventilators and annular spaces around funnels and...with a fixed bilge system, vents and ventilators may be omitted from void spaces....

2010-10-01

446

Utilizing Passive Ventilation to Complement HVAC Systems in Enclosed Buildings  

E-print Network

Utilizing Passive Ventilation to Complement HVAC Systems in Enclosed Buildings Tom Rogg REU Student are important considerations in building design. Incorporation of a combination of passive ventilation systems of the National Science Foundation. Research Objectives · To provide proof of concept that a passive ventilation

Mountziaris, T. J.

447

Variable ventilation induces endogenous surfactant release in normal guinea pigs  

E-print Network

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.00036.2003.--Variable or noisy ventilation, which includes random breath-to-breath variations in tidal

Lutchen, Kenneth

448

46 CFR 92.15-10 - Ventilation for closed spaces.  

...be provided to close off all vents and ventilators. (b) Means shall be provided...spaces and for closing all doorways, ventilators and annular spaces around funnels and...with a fixed bilge system, vents and ventilators may be omitted from void spaces....

2014-10-01

449

Estimating ventilation time scales using overturning stream functions  

E-print Network

Estimating ventilation time scales using overturning stream functions Bijoy Thompson & Jonas for estimating ventilation time scales from overturning stream functions is proposed. The stream function may describing an ide- alized semi-enclosed ocean basin ventilated through a narrow strait over a sill

Döös, Kristofer

450

AIR FLOW MODELING IN DEEP WELLS: APPLICATION TO MINING VENTILATION  

E-print Network

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

Johansson, Karl Henrik

451

46 CFR 171.118 - Automatic ventilators and side ports.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Automatic ventilators and side ports. 171.118 Section...Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must not be fitted in the side of...

2013-10-01

452

46 CFR 92.15-10 - Ventilation for closed spaces.  

Code of Federal Regulations, 2013 CFR

...be provided to close off all vents and ventilators. (b) Means shall be provided...spaces and for closing all doorways, ventilators and annular spaces around funnels and...with a fixed bilge system, vents and ventilators may be omitted from void spaces....

2013-10-01

453

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

Code of Federal Regulations, 2013 CFR

...ventilated in a manner suitable for the purpose of the space. (b) A means must be provided to close off all vents and ventilators. (c) Living spaces must be ventilated by a mechanical system unless it can be shown that a natural system...

2013-10-01

454

The effect of fabric air permeability on clothing ventilation  

Microsoft Academic Search

Dry and evaporative heat losses of clothed people are highly affected by the air exchange between the clothing microclimate and the environment. This air exchange, or clothing ventilation, is highly affected by the air permeability of the fabric materials as well as the clothing design. To examine the effect of the air permeability of fabric on clothing ventilation, the ventilation

Hiroyuki Ueda; George Havenith

2005-01-01

455

Modeling deposition of particles in typical horizontal ventilation duct flows  

Microsoft Academic Search

Particles carried by airflows through ventilation ducts in heating, ventilation and air-conditioning (HVAC) systems have adverse effects on human health. Knowledge of particle deposition rates in ventilation ducts is useful for modeling exposures to particles within buildings and more completely understanding particle fates. To meet these objectives, deposition rates of particles to various internal surfaces in a smooth horizontal square

Jinping Zhang; Angui Li; Desheng Li

2008-01-01

456

Ventilation planning at Energy West's Deer Creek mine  

SciTech Connect

In 2004 ventilation planning was initiated to exploit a remote area of Deer Creek mine's reserve (near Huntington, Utah), the Mill Fork Area, located under a mountain. A push-pull ventilation system was selected. This article details the design process of the ventilation system upgrade, the procurement process for the new fans, and the new fan startup testing. 5 figs., 1 photo.

Tonc, L.; Prosser, B.; Gamble, G. [Pacific Corp., Huntington, UT (United States)

2009-08-15

457

Numerical studies on performance evaluation of tunnel ventilation safety systems  

Microsoft Academic Search

The performance of tunnel safety systems for fire protection and ventilation provision is evaluated using Computational Fluid Dynamics (CFD). Ventilation safety systems commonly used in tunnels are reviewed first. The safety aspects related to tunnel fire and ventilation are then discussed. Air flow induced by an accidental vehicular fire in a tunnel is simulated using CFD. Based on the results,

Jojo S. M Li; W. K Chow

2003-01-01

458

46 CFR 78.47-75 - Ventilation alarm failure.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 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...

2012-10-01

459

46 CFR 78.47-75 - Ventilation alarm failure.  

Code of Federal Regulations, 2011 CFR

...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...

2011-10-01

460

46 CFR 78.47-75 - Ventilation alarm failure.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 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...

2010-10-01

461

46 CFR 97.37-50 - Ventilation alarm failure.  

Code of Federal Regulations, 2012 CFR

...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...

2012-10-01

462

46 CFR 97.37-50 - Ventilation alarm failure.  

Code of Federal Regulations, 2010 CFR

...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...

2010-10-01

463

46 CFR 97.37-50 - Ventilation alarm failure.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 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...

2013-10-01

464

46 CFR 78.47-75 - Ventilation alarm failure.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 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...

2013-10-01

465

46 CFR 97.37-50 - Ventilation alarm failure.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 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...

2011-10-01

466

Contribution of Gular Pumping to Lung Ventilation in Monitor  

E-print Network

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

Brainerd, Elizabeth

467

46 CFR 78.47-75 - Ventilation alarm failure.  

...2014-10-01 2014-10-01 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...

2014-10-01

468

Zone Modelinq of Forced Ventilation Fires  

Microsoft Academic Search

In 1982, the Nuclear Regulatory Commission posed a forced-ventilation problem which is described. The algorithm developed for its solution is discussed. This was embedded in the Harvard Mark 5.3 computer code, and predictions then made for the outcome of aseries of experiments carried out at Lawrence Livermore Laboratory (see previous paper). Comparisons are made between the predicted and the actual

Henri E. Mitler

1984-01-01

469

46 CFR 72.05-50 - Ventilation.  

Code of Federal Regulations, 2011 CFR

...required to meet bulkhead requirements, the space within the duct shall be considered to be the same as the space served by the ventilator, and the duct shall be insulated to meet the applicable requirements of tables 72.05-10(d) and...

2011-10-01

470

46 CFR 72.05-50 - Ventilation.  

...required to meet bulkhead requirements, the space within the duct shall be considered to be the same as the space served by the ventilator, and the duct shall be insulated to meet the applicable requirements of tables 72.05-10(d) and...

2014-10-01

471

46 CFR 72.05-50 - Ventilation.  

Code of Federal Regulations, 2010 CFR

...required to meet bulkhead requirements, the space within the duct shall be considered to be the same as the space served by the ventilator, and the duct shall be insulated to meet the applicable requirements of tables 72.05-10(d) and...

2010-10-01

472

Including Children Dependent on Ventilators in School.  

ERIC Educational Resources Information Center

Guidelines for including ventilator-dependent children in school are offered, based on experience with six such students at a New York State school. Guidelines stress adherence to the medical management plan, the school-family partnership, roles of the social worker and psychologist, orientation, transportation, classroom issues, and steps toward…

Levine, Jack M.

1996-01-01

473

46 CFR 72.05-50 - Ventilation.  

Code of Federal Regulations, 2013 CFR

...required to meet bulkhead requirements, the space within the duct shall be considered to be the same as the space served by the ventilator, and the duct shall be insulated to meet the applicable requirements of tables 72.05-10(d) and...

2013-10-01

474

46 CFR 72.05-50 - Ventilation.  

Code of Federal Regulations, 2012 CFR

...required to meet bulkhead requirements, the space within the duct shall be considered to be the same as the space served by the ventilator, and the duct shall be insulated to meet the applicable requirements of tables 72.05-10(d) and...

2012-10-01

475

Does Mixing Make Residential Ventilation More Effective?  

SciTech Connect

Ventilation dilutes or removes indoor contaminants to reduce occupant exposure. In a multi-zone environment such as a house, there will be different dilution rates and different source strengths in every zone. The total ventilation rate is the most important factor in determining the exposure of occupants to given sources, but the zone- specific distribution of exhaust and supply air, and the mixing of ventilation air can have significant roles. Different types of ventilation systems will provide different amounts of mixing depending on several factors such as air leakage through the building envelope, air distribution systems and the location of sources and occupants. This paper reports recent results of investigations to determine the impact that air mixing has on exposures of residential occupants to prototypical contaminants of concern. Evaluations of existing field measurements and simulations reported in the literature are combined with new analyses to provide an integrated overview of the topic. The results show that for extreme cases additional mixing can be a significant factor but for typical homes looking at average exposures mixing is not helpful and can even make exposures worse.

Sherman, Max; Walker, Iain

2010-08-16

476

VENTILATING HORNETS DISPLAY DIFFERENTIAL BODY TEMPERATURE  

Microsoft Academic Search

abdomen bent downward at a 90? angle to the thorax, their antennae vibrating, and their wings beating rapidly for minutes at a time. Eventually these hornets leave their position, either to retreat into the nest or else to fly off to the field, and are replaced by new hornets that assume the ventilation task. Infra-red (IR) photography reveals that in

Jacob S. Ishay; Marian Plotkin; Natalya Ermakov; Alon Goren; David J. Bergman

2006-01-01

477

Fire protection countermeasures for containment ventilation systems  

Microsoft Academic Search

The goal of this project is to find countermeasures to protect High Efficiency Particulate Air (HEPA) filters, in exit ventilation ducts, from the heat and smoke generated by fire. Initially, methods were developed to cool fire-heated air by fine water spray upstream of the filters. It was recognized that smoke aerosol exposure to HEPA filters could also cause disruption of

N. Alvares; D. Beason; V. Bergman; J. Creighton; H. Ford; A. Lipska

1980-01-01

478

Metrics for Air Conditioning & Refrigeration, Heating, Ventilating.  

ERIC Educational Resources Information Center

Designed to meet the job-related metric measurement needs of the air conditioning and refrigeration, heating and ventilating student, this instructional package is one of three for the construction occupations cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already…

Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

479

Prevention of ventilator-associated pneumonia  

Microsoft Academic Search

Ventilator-associated pneumonia (VAP) remains a common complication within the intensive care unit. Despite identification of the patients at highest risk for developing VAP, the actual incidence appears to be unchanged over the past two decades. Colonization of the oral pharynx with pathogenic organisms and ongoing aspiration appear to be necessary in the development of VAP. Thus, prevention strategies targeted at

David H Livingston

2000-01-01

480

Teaching Alveolar Ventilation with Simple, Inexpensive Models  

ERIC Educational Resources Information Center

When teaching and learning about alveolar ventilation with our class of 300 first-year medical students, we use four simple, inexpensive "models." The models, which encourage research-oriented learning and help our students to understand complex ideas, are distributed to the students before class. The students anticipate something new every day,…

DiCarlo, Stephen E.

2008-01-01

481

Modeling particle loss in ventilation ducts  

SciTech Connect

Empirical equations were developed and applied to predict losses of 0.01-100 {micro}m airborne particles making a single pass through 120 different ventilation duct runs typical of those found in mid-sized office buildings. For all duct runs, losses were negligible for submicron particles and nearly complete for particles larger than 50 {micro}m. The 50th percentile cut-point diameters were 15 {micro}m in supply runs and 25 {micro}m in return runs. Losses in supply duct runs were higher than in return duct runs, mostly because internal insulation was present in portions of supply duct runs, but absent from return duct runs. Single-pass equations for particle loss in duct runs were combined with models for predicting ventilation system filtration efficiency and particle deposition to indoor surfaces to evaluate the fates of particles of indoor and outdoor origin in an archetypal mechanically ventilated building. Results suggest that duct losses are a minor influence for determining indoor concentrations for most particle sizes. Losses in ducts were of a comparable magnitude to indoor surface losses for most particle sizes. For outdoor air drawn into an unfiltered ventilation system, most particles smaller than 1 {micro}m are exhausted from the building. Large particles deposit within the building, mostly in supply ducts or on indoor surfaces. When filters are present, most particles are either filtered or exhausted. The fates of particles generated indoors follow similar trends as outdoor particles drawn into the building.

Sippola, Mark R.; Nazaroff, William W.

2003-04-01

482

Air Distribution Effectiveness for Different Mechanical Ventilation  

E-print Network

LBNL-62700 Air Distribution Effectiveness for Different Mechanical Ventilation Systems Max H Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;1 Air Distribution depending on the effectiveness of their air distribution systems and the location of sources and occupants

483

Simulation of forced-ventilation fires  

SciTech Connect

Fire hazard descriptions and compartment fire models are assessed as input to airflow network analysis methods that simulate the exposure of ventilation system components to fire products. The assessment considered the availability of hazard descriptions and models for predicting simultaneous heat and mass release at special compartment openings that are characterized by a one-dimensional and controllable volumetric flux.

Krause, F.R.; Gregory, W.S.

1982-01-01

484

Gas exchange and intrapulmonary distribution of ventilation during continuous-flow ventilation  

SciTech Connect

In 12 anesthetized paralyzed dogs, pulmonary gas exchange and intrapulmonary inspired gas distribution were compared between continuous-flow ventilation (CFV) and conventional mechanical ventilation (CMV). Nine dogs were studied while they were lying supine, and three dogs were studied while they were lying prone. A single-lumen catheter for tracheal insufflation and a double-lumen catheter for bilateral endobronchial insufflation (inspired O2 fraction = 0.4; inspired minute ventilation = 1.7 +/- 0.3 (SD) 1.kg-1.min-1) were evaluated. Intrapulmonary gas distribution was assessed from regional 133Xe clearances. In dogs lying supine, CO2 elimination was more efficient with endobronchial insufflation than with tracheal insufflation, but the alveolar-arterial O2 partial pressure difference was larger during CFV than during CMV, regardless of the type of insufflation. By contrast, endobronchial insufflation maintained both arterial PCO2 and alveolar-arterial O2 partial pressure difference at significantly lower levels in dogs lying prone than in dogs lying supine. In dogs lying supine, the dependent lung was preferentially ventilated during CMV but not during CFV. In dogs lying prone, gas distribution was uniform with both modes of ventilation. The alveolar-arterial O2 partial pressure difference during CFV in dogs lying supine was negatively correlated with the reduced ventilation of the dependent lung, which suggests that increased ventilation-perfusion mismatching was responsible for the increase in alveolar-arterial O2 partial pressure difference. The more efficient oxygenation during CFV in dogs lying prone suggests a more efficient matching of ventilation to perfusion, presumably because the distribution of blood flow is also nearly uniform.

Vettermann, J.; Brusasco, V.; Rehder, K.

1988-05-01

485

International Journal of Ventilation ISSN 1473-3315 Volume 4 No 4 Interacting Turbulent Plumes in a Naturally Ventilated Enclosure  

E-print Network

International Journal of Ventilation ISSN 1473-3315 Volume 4 No 4 ________________________________________________________________________________________________________________________ ________________________________________________________________________________________________________________________ 301 Interacting Turbulent Plumes in a Naturally Ventilated Enclosure P. F. Linden1 and N. B. Kaye2 1 of turbulent plumes is examined in the context of building ventilation flows. Recent models for natural

Linden, Paul F.

486

Pitfalls of mechanical ventilation in Thailand.  

PubMed

Pitfalls in the respiratory care and mechanical ventilation for patients continue to prevail in intensive care unit (ICU) or in some hospital wards in Thailand. There are two reasons that explain this phenomenon. Firstly, there are no professional respiratory therapists in Thailand. Secondly, most caregivers do not possess the adequate knowledge and skills requiredfor respiratory care and for initiating, maintaining and weaning patients off mechanical ventilation. Physicians and nurses have to practice in respiratory care and mechanical ventilation without participating in adequate training during their undergraduate studies and postgraduate training. In reality, physicians pay almost no attention to respiratory care. They leave the respiratory toilet, ventilator changes and monitoring of the patients to nurses who have many other tasks to attend to. To solve this problem will require restructuring of the Thai healthcare system. The Parliament will need to pass a "Respiratory Therapy Profession Act" to certify "respiratory therapists " as a new, registered health profession. The Office of the Civil Service Commission has to take the responsibility for creating the job title and a job description for respiratory therapists. Academic institutes have to provide training courses in respiratory therapy and grant appropriate levels of diplomas or certificates in respiratory therapy. Did actics and clinical skills required for respiratory care have to be sufficiently integrated into the curricula for medical students as well as nursing students. Physicians and nurses need to master their skills and acquired appropriate knowledge in respiratory care and mechanical ventilation until we can assure the necessary number of registered or certified respiratory therapists here in Thailand to help avoid such pitfalls. PMID:24855857

Bunburaphong, Thananchai

2014-01-01

487

On The Valuation of Infiltration towards Meeting Residential Ventilation Needs  

SciTech Connect

The purpose of ventilation is dilute or remove indoor contaminants that an occupant is exposed to. It can be provided by mechanical or natural means. In most homes, especially existing homes, infiltration provides the dominant fraction of the ventilation. As we seek to provide acceptable indoor air quality at minimum energy cost, it is important to neither over-ventilate nor under-ventilate. Thus, it becomes critically important to correctly evaluate the contribution infiltration makes to both energy consumption and equivalent ventilation. 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.

Sherman, Max H.

2008-09-01

488

SY Tank Farm ventilation isolation option risk assessment report  

SciTech Connect

The safety of the 241-SY Tank Farm ventilation system has been under extensive scrutiny due to safety concerns associated with tank 101-SY. Hydrogen and other gases are generated and trapped in the waste below the liquid surface. Periodically, these gases are released into the dome space and vented through the exhaust system. This attention to the ventilation system has resulted in the development of several alternative ventilation system designs. The ventilation system provides the primary means of mitigation of accidents associated with flammable gases. This report provides an assessment of various alternatives ventilation system designs.

Powers, T.B.; Morales, S.D.

1994-03-01

489

Factors associated with multimorbidity and its link with poor blood pressure control among 223,286 hypertensive patients.  

PubMed

Multimorbidity has become the norm worldwide as populations age. It remains, however, infrequently researched. This study evaluated factors associated with multimorbidity in a predominantly Chinese hypertensive population. We included all adult patients prescribed their first antihypertensive agents in the entire public sector in Hong Kong from a validated database. Multimorbidity was defined as having one or more medical conditions (cardiovascular diseases; respiratory diseases; diabetes or impaired fasting glucose; renal disease) in addition to hypertension. We studied the prevalence of multimorbidity and performed multinomial regression analyses to evaluate factors independently associated with multimorbidity. 223,286 hypertensive patients (average age of 59.9years, SD 17.6) were included. The prevalence of having 0, 1 and ?2 additional conditions was 59.6%, 32.8% and 7.5%, respectively. The most common conditions were cardiovascular disease (24.2%) and diabetes (23.0%), followed by respiratory disorders (14.6%) and renal disease (10.9%). Older age (>50years), male sex, lower household income, receipt of social security allowance and suboptimal blood pressure control (>140mmHg or >90mmHg; >130mmHg or >80mmHg for diabetes patients; AOR=3.38-4.49) were significantly associated with multimorbidity. There exists a synergistic effect among these variables as older (?70years), male patients receiving security allowance had substantially higher prevalence of multimorbidity (19.9% vs 7.5% among all patients). Multimorbidity is very common in hypertensive patients and its prevalence increased markedly with the presence of risk factors identified in this study. Hypertensive patients with multimorbidities should receive more meticulous clinical care as their blood pressure control tends to be poorer. PMID:25499379

Wong, Martin C S; Wang, Harry H X; Cheung, Clement S K; Tong, Ellen L H; Sek, Antonio C H; Cheung, N T; Yan, Bryan P Y; Yu, Cheuk-Man; Griffiths, Sian M; Coats, Andrew J S

2014-11-15

490

Take Control of Your Blood pressure (TCYB) study: A multifactorial tailored behavioral and educational intervention for achieving blood pressure control  

PubMed Central

Objectives Evaluating a randomized controlled trial involving a tailored behavioral intervention conducted to improve blood pressure control. Methods Adults with hypertension from two outpatient primary care clinics were randomly allocated to receive a nurse-administered behavioral intervention or usual care. In this ongoing study, patients receive the tailored behavioral intervention bi-monthly for two years via telephone; the goal of the intervention is to promote medication adherence and improve hypertension-related health behaviors. Patient factors targeted in the tailored behavioral intervention include perceived risk of hypertension and knowledge, memory, medical and social support, patients' relationship with their health care provider, adverse effects of medication therapy, weight management, exercise, diet, stress, smoking, and alcohol use. Results The sample randomized to the behavioral intervention consisted of 319 adults with hypertension (average age = 60.5 years; 47% African-American). A comparable sample of adults was assigned to usual care (n=317). We had a 96% retention rate for the overall sample for the first 6 months of the study (93% at 12 months). The average phone call has lasted 18 minutes (range 2 to 51 minutes). From baseline to six months, self-reported medication adherence increased by 9% in the behavioral group vs. 1% in the non-behavioral group. Conclusion The intervention is easily implemented and is designed to enhance adherence with prescribed hypertension regimen. The study includes both general and patient-tailored information based upon need assessment. The study design ensures internal validity as well as the ability to generalize study findings to the clinic settings. Practice Implications Despite knowledge of the risks and acceptable evidence, a large number of hypertensive adults still do not have their blood pressure under effective control. This study will be an important step in evaluating a tailored multibehavioral intervention focusing on improving blood pressure control. PMID:18164894

Bosworth, Hayden B.; Olsen, Maren K; Neary, Alice; Orr, Melinda; Grubber, Janet; Svetkey, Laura; Adams, Martha; Oddone, Eugene Z.

2008-01-01

491

Continuous distributions of specific ventilation recovered from inert gas washout  

NASA Technical Reports Server (NTRS)

A new technique is described for recovering continuous distributions of ventilation as a function of tidal ventilation/volume ratio from the nitrogen washout. The analysis yields a continuous distribution of ventilation as a function of tidal ventilation/volume ratio represented as fractional ventilations of 50 compartments plus dead space. The procedure was verified by recovering known distributions from data to which noise had been added. Using an apparatus to control the subject's tidal volume and FRC, mixed expired N2 data gave the following results: (a) the distributions of young, normal subjects were narrow and unimodal; (b) those of subjects over age 40 were broader with more poorly ventilated units; (c) patients with pulmonary disease of all descriptions showed enlarged dead space; (d) patients with cystic fibrosis showed multimodal distributions with the bulk of the ventilation going to overventilated units; and (e) patients with obstructive lung disease fell into several classes, three of which are illustrated.

Lewis, S. M.; Evans, J. W.; Jalowayski, A. A.

1978-01-01

492

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

493

Ventilator associated pneumonia and infection control  

PubMed Central

Ventilator associated pneumonia (VAP) is the leading cause of morbidity and mortality in intensive care units. The incidence of VAP varies from 7% to 70% in different studies and the mortality rates are 20–75% according to the study population. Aspiration of colonized pathogenic microorganisms on the oropharynx and gastrointestinal tract is the main route for the development of VAP. On the other hand, the major risk factor for VAP is intubation and the duration of mechanical ventilation. Diagnosis remains difficult, and studies showed the importance of early initiation of appropriate antibiotic for prognosis. VAP causes extra length of stay in hospital and intensive care units and increases hospital cost. Consequently, infection control policies are more rational and will save money. PMID:16600048

Alp, Emine; Voss, Andreas

2006-01-01

494

Cooling and ventilating the Abyssal Ocean  

NASA Astrophysics Data System (ADS)

The abyssal ocean is filled with cold, dense waters that sink along the Antarctic continental slope and overflow sills that lie south of the Nordic Seas. Recent integrations of chlorofluorocarbon-11 (CFC) measurements are similar in Antarctic Bottom Water (AABW) and in lower North Atlantic Deep Water (NADW), but Antarctic inputs are ? 2°C colder than their northern counterparts. This indicates comparable ventilation rates from both polar regions, and accounts for the Southern Ocean dominance over abyssal cooling. The decadal CFC-based estimates of recent ventilation are consistent with other hydrographic observations and with longer-term radiocarbon data, but not with hypotheses of a 20th-century slowdown in the rate of AABW formation. Significant variability is not precluded by the available ocean measurements, however, and interannual to decadal changes are increasingly evident at high latitudes.

Orsi, Alejandro H.; Jacobs, Stanley S.; Gordon, Arnold L.; Visbeck, Martin

495

Association of compliance of ventilator bundle with incidence of ventilator-associated pneumonia and ventilator utilization among critical patients over 4 years  

PubMed Central

BACKGROUND: Several studies showed that the implementation of the Institute for Healthcare Improvement (IHI) ventilator bundle alone or with other preventive measures are associated with reducing Ventilator-Associated Pneumonia (VAP) rates. However, the association with ventilator utilization was rarely examined and the findings were conflicting. The objectives were to validate the bundle association with VAP rate in a traditionally high VAP environment and to examine its association with ventilator utilization. MATERIALS AND METHODS: The study was conducted at the adult medical-surgical intensive care unit (ICU) at King Abdulaziz Medical City, Saudi Arabia, between 2010 and 2013. VAP data were collected by a prospective targeted surveillance as per Centers for Disease Control and Prevention (CDC)/National Healthcare Safety Network (NHSN) methodology while bundle data were collected by a cross-sectional design as per IHI methodology. RESULTS: Ventilator bundle compliance significantly increased from 90% in 2010 to 97% in 2013 (P for trend < 0.001). On the other hand, VAP rate decreased from 3.6 (per 1000 ventilator days) in 2010 to 1.0 in 2013 (P for trend = 0.054) and ventilator utilization ratio decreased from 0.73 in 2010 to 0.59 in 2013 (P for trend < 0.001). There were negative significant correlations between the trends of ventilator bundle compliance and VAP rate (cross-correlation coefficients ?0.63 to 0.07) and ventilator utilization (cross-correlation coefficients ?0.18 to ?0.63). CONCLUSION: More than 70% improvement of VAP rates and approximately 20% improvement of ventilator utilization were observed during IHI ventilator bundle implementation among adult critical patients in a tertiary care center in Saudi Arabia. Replicating the current finding in multicenter randomized trials is required before establishing any causal link. PMID:25276241

Al-Thaqafy, Majid S.; El-Saed, Aiman; Arabi, Yaseen M.; Balkhy, Hanan H.

2014-01-01

496

STATE OF CALIFORNIA MECHANICAL VENTILATION AND REHEAT  

E-print Network

or equal to H, or use Transfer Air (column N) to make up the difference. J Design fan supply cfm (Fan CFM'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 of Columns H, J, K, 300 cfm Design minimum Air setpoint Transfer Air 15 15 15 15 15 15 15 15 15 15 15 15

497

Noninvasive ventilation in acute respiratory failure  

PubMed Central

After the institution of positive-pressure ventilation, the use of noninvasive ventilation (NIV) through an interface substantially increased. The first technique was continuous positive airway pressure; but, after the introduction of pressure support ventilation at the end of the 20th century, this became the main modality. Both techniques, and some others that have been recently introduced and which integrate some technological innovations, have extensively demonstrated a faster improvement of acute respiratory failure in different patient populations, avoiding endotracheal intubation and facilitating the release of conventional invasive mechanical ventilation. In acute settings, NIV is currently the first-line treatment for moderate-to-severe chronic obstructive pulmonary disease exacerbation as well as for acute cardiogenic pulmonary edema and should be considered in immunocompromised patients with acute respiratory insufficiency, in difficult weaning, and in the prevention of postextubation failure. Alternatively, it can also be used in the postoperative period and in cases of pneumonia and asthma or as a palliative treatment. NIV is currently used in a wide range of acute settings, such as critical care and emergency departments, hospital wards, palliative or pediatric units, and in pre-hospital care. It is also used as a home care therapy in patients with chronic pulmonary or sleep disorders. The appropriate selection of patients and the adaptation to the technique are the keys to success. This review essentially analyzes the evidence of benefits of NIV in different populations with acute respiratory failure and describes the main modalities, new devices, and some practical aspects of the use of this technique. PMID:25143721

Mas, Arantxa; Masip, Josep

2014-01-01

498

Performance Assessment of Photovoltaic Attic Ventilator Fans  

E-print Network

PERFORMANCE ASSESSMENT OF PHOTOVOLTAIC ATTIC VENTILATOR FANS Danny S. Parker John R. Shenvin Principal Research Scientist Research Engineer Florida Solar Energy Center Cocoa, Florida 32922 ABSTRACT Controlling summer attic heat gain... system is 7.300 Btu/hr if the cooling system ran the full hour under daign conditions- more than twice the ceiling flux. conditioning energy in 48 Central Florida homes conducted by Cummings (1 99 1 ) which found that homes with the air handlers...

Parker, D. S.; Sherwin, J. R.

2000-01-01

499

Advanced Controls for Residential Whole-House Ventilation Systems  

SciTech Connect

Whole-house ventilation systems are becoming commonplace in new construction, remodeling/renovation, and weatherization projects, driven by combinations of specific requirements for indoor air quality (IAQ), health and compliance with standards, such as ASHRAE 62.2. Ventilation systems incur an energy penalty on the home via fan power used to drive the airflow, and the additional space-conditioning load associated with heating or cooling the ventilation air. Finding a balance between IAQ and energy use is important if homes are to be adequately ventilated while not increasing the energy burden. This study used computer simulations to examine RIVEC the Residential Integrated Ventilation Controller - a prototype ventilation controller that aims to deliver whole-house ventilation rates that comply with ventilation standards, for the minimum use of energy. Four different whole-house ventilation systems were simulated, both with and without RIVEC, so that the energy and IAQ results could be compared. Simulations were conducted for 13 US climate zones, three house designs, and three envelope leakage values. The results showed that the RIVEC controller could typically return ventilation energy savings greater than 40percent without compromising long-term chronic or short-term acute exposures to relevant indoor contaminants. Critical and average peak power loads were also reduced as a consequence of using RIVEC.

Turner, William; Walker, Iain; Sherman, Max

2014-08-01

500

Why we ventilate our houses - An historical look  

SciTech Connect

The knowledge of how to ventilate buildings, and how much ventilation is necessary for human health and comfort, has evolved over centuries of trial and error. Humans and animals have developed successful solutions to the problems of regulating temperature and removing air pollutants through the use of ventilation. These solutions include ingenious construction methods, such as engineered passive ventilation (termite mounds and passive stacks), mechanical means (wing-powered, fans), and an evolving effort to identify problems and develop solutions. Ventilation can do more than help prevent building occupants from getting sick; it can provide an improved indoor environment. Codes and standards provide minimum legal requirements for ventilation, but the need for ventilation goes beyond code minima. In this paper we will look at indoor air pollutant sources over time, the evolution of ventilation strategies, current residential ventilation codes and standards (e.g., recently approved ASHRAE Standard 62.2), and briefly discuss ways in which we can go beyond the standards to optimize residential ventilation, reduce indoor air quality problems, and provide corresponding social and economic benefit.

Matson, Nance E.; Sherman, Max H.

2004-05-14