30 CFR 250.444 - What are the choke manifold requirements?

Code of Federal Regulations, 2012 CFR

2012-07-01

... THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.444 What are the choke manifold..., and abrasiveness of drilling fluids and well fluids that you may encounter. (b) Choke manifold...

Solitary Participation in the "Choking Game" in Oregon.

PubMed

Ibrahim, Alexandra P; Knipper, Sarah H; Brausch, Amy M; Thorne, Elizabeth K

2016-12-01

The purpose of this study was to compare characteristics of youth who participate in the choking game alone versus those who participate in a group. Lifetime prevalence estimates were obtained from the 2011 (n = 5682) and 2013 (n = 15 150) Oregon Healthy Teens survey. The 2011 and 2013 data sets were merged (N = 20 832) to compare youth who participate alone versus those who participate in a group in the choking game. Multivariate modeling was conducted to examine individual characteristics of young people who engaged in the choking game alone versus those who engaged in the game in a group. In 2011, 3.8% of eighth-grade participants reported a lifetime prevalence of choking game participation; 3.7% reported lifetime prevalence of participation in 2013. In the merged 2011/2013 data set, 17.6% (n = 93) of choking game participants indicated that they had participated alone. Compared with those who reported participating in a group, youth who participated alone had significantly higher rates of suicide contemplation (odds ratio: 4.58; P < .001) and poor mental health (odds ratio: 2.13; P < .05). Youth who participate alone in the choking game are a particularly high risk group, exhibiting substantially higher rates of suicidal ideation and poorer mental health compared with youth who participate in the choking game in a group. Adolescent health care providers should be aware of these associations, assess whether prevention messaging is appropriate, and be prepared to explain the high risks of morbidity and mortality associated with participation. Copyright © 2016 by the American Academy of Pediatrics.

Unstart phenomena induced by flow choking in scramjet inlet-isolators

NASA Astrophysics Data System (ADS)

Im, Seong-kyun; Do, Hyungrok

2018-02-01

A review of recent research outcomes in downstream flow choking-driven unstart is presented. Unstart is a flow phenomenon at the inlet that severely reduces the air mass flow rate through the engine, causing a loss of thrust and considerable transient mechanical loading. Therefore, unstart in a scramjet engine crucially affects the design and the operation range of hypersonic vehicles. Downstream flow choking is known to be one of the major mechanisms inducing inlet unstart, as confirmed by recent scramjet-powered flight tests. The current paper examines recent research progress in identifying flow choking mechanisms that trigger unstart. Three different flow choking mechanisms are discussed: flow blockage, mass addition, and heat release from combustion reactions. Current research outcomes on the characteristic of unstarting flows, such as transient and quasi-steady motions, are reviewed for each flow choking mechanism. The characteristics of unstarted flows are described including Buzzing phenomena and oscillatory motions of unstarted shockwaves. Then, the state-of-the-art methods to predict, detect, and control unstart are presented. The review suggests that further investigations with high-enthalpy ground facilities will aid understanding of heat release-driven unstart.

Computer analysis of flow perturbations generated by placement of choke bumps in a wind tunnel

NASA Technical Reports Server (NTRS)

Campbell, R. L.

1981-01-01

An inviscid analytical study was conducted to determine the upstream flow perturbations caused by placing choke bumps in a wind tunnel. A computer program based on the stream-tube curvature method was used to calculate the resulting flow fields for a nominal free-stream Mach number range of 0.6 to 0.9. The choke bump geometry was also varied to investigate the effect of bump shape on the disturbance produced. Results from the study indicate that a region of significant variation from the free-stream conditions exists upstream of the throat of the tunnel. The extent of the disturbance region was, as a rule, dependent on Mach number and the geometry of the choke bump. In general, the upstream disturbance distance decreased for increasing nominal free-stream Mach number and for decreasing length-to-height ratio of the bump. A polynomial-curve choke bump usually produced less of a disturbance than did a circular-arc bump and going to an axisymmetric configuration (modeling choke bumps on all the tunnel walls) generally resulted in a lower disturbance than with the corresponding two dimensional case.

Indicators of choking risk in adults with learning disabilities: a questionnaire survey and interview study.

PubMed

Thacker, Alice; Abdelnoor, Adam; Anderson, Claire; White, Sarah; Hollins, Sheila

2008-01-01

Feeding and swallowing impairments are key predictors of increased morbidity and mortality in adults with learning disabilities. This postal survey and interview study sought to identify risk factors in adults with learning disabilities who have histories of choking. A total of 2000 questionnaires were sent to carers of all adults with learning disabilities registered as service users by three local health authorities. (A 'service user' may be using any specialist learning disability health or social care facility with day, residential or therapeutic services). Of the 674 service users for whom surveys were returned, 47 were living in hospital, 396 were living in residential or group homes and 208 were living with relatives, or in their own homes. Eighteen subjects who had reported serious or repeated episodes of choking were interviewed in depth in their residences or workplaces. Responses were subjected to frequency analyses. Personal characteristics were analysed. Choking patterns were differentiated by food texture. A total of 34% of questionnaires on 674 service users were returned; 42% of respondents reported one or more choking episodes. There was a significantly greater occurrence of choking among people with more severe learning disability, with Down syndrome, people who had an incomplete dentition or were taking a greater number of psychotropic drugs. Antisocial eating habits learnt in institutional settings presented an additional choking hazard for some individuals. Choking is a serious hazard for many adults with learning disabilities. This study establishes many of the characteristics associated with swallowing problems in this population. Clinicians and carers should benefit from awareness of these predictors, leading to better management of eating behaviours and habits. A choking and swallowing risk assessment should be included in routine health assessments of adults with learning disability, paying especial attention to the condition of a person's teeth; possible side effects from prescribed medication, and abnormal eating behaviour.

30 CFR 250.1624 - Blowout prevention equipment.

Code of Federal Regulations, 2013 CFR

2013-07-01

... station and one BOP-control station on the rig floor; and (5) A choke line and a kill line each equipped with two full-opening valves and a choke manifold. One of the choke-line valves and one of the kill-line valves shall be remotely controlled except that a check valve may be installed on the kill line in...

30 CFR 250.1624 - Blowout prevention equipment.

Code of Federal Regulations, 2012 CFR

2012-07-01

... station and one BOP-control station on the rig floor; and (5) A choke line and a kill line each equipped with two full-opening valves and a choke manifold. One of the choke-line valves and one of the kill-line valves shall be remotely controlled except that a check valve may be installed on the kill line in...

30 CFR 250.1624 - Blowout prevention equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... station and one BOP-control station on the rig floor; and (5) A choke line and a kill line each equipped with two full-opening valves and a choke manifold. One of the choke-line valves and one of the kill-line valves shall be remotely controlled except that a check valve may be installed on the kill line in...

30 CFR 250.1624 - Blowout prevention equipment.

Code of Federal Regulations, 2014 CFR

2014-07-01

... station and one BOP-control station on the rig floor; and (5) A choke line and a kill line each equipped with two full-opening valves and a choke manifold. One of the choke-line valves and one of the kill-line valves shall be remotely controlled except that a check valve may be installed on the kill line in...

Choking under monitoring pressure: being watched by the experimenter reduces executive attention.

PubMed

Belletier, Clément; Davranche, Karen; Tellier, Idriss S; Dumas, Florence; Vidal, Franck; Hasbroucq, Thierry; Huguet, Pascal

2015-10-01

Performing more poorly given one's skill level ("choking") is likely in situations that offer an incentive if a certain outcome is achieved (outcome pressure) or when one is being watched by others-especially when one's performance is being evaluated (monitoring pressure). According to the choking literature, outcome pressure is associated with reduced executive control of attention, whereas monitoring pressure is associated with increased, yet counterproductive, attention to skill processes. Here, we show the first evidence that monitoring pressure-being watched by the experimenter-may lead individuals with higher working memory to choke on a classic measure of executive control-just the task effect thought to result from outcome pressure. Not only does this finding help refine our understanding of the processes underlying choking under monitoring pressure, but it also leads to a new look at classic audience effects, with an important implication for experimental psychology.

Choking under the pressure of a positive stereotype: gender identification and self-consciousness moderate men's math test performance.

PubMed

Tagler, Michael J

2012-01-01

Choking under pressure occurs when an individual underperforms due to situational pressure. The present study examined whether being the target of a positive social stereotype regarding math ability causes choking among men. Gender identification and self-consciousness were hypothesized to moderate the effect of math-gender stereotypes on men's math test performance. Men high in self-consciousness but low in gender identification significantly underperformed when exposed to gender-relevant test instructions. No significant effects were found under a gender-irrelevant condition. These findings are discussed in the contexts of research on stereotype threat, stereotype lift, and choking under pressure.

Mimics of child abuse: Can choking explain abusive head trauma?

PubMed

Edwards, George A

2015-10-01

Choking is one of the alternative explanations of abusive head trauma in children that have been offered in courtroom testimony and in the media. Most of these explanations - including choking - are not scientifically supported. This article highlights four points. (1) The origins of choking as an explanation for intracranial and retinal hemorrhages are speculative. (2) Choking has been used in high profile court testimony as an explanation for the death of a child thought to have been abused. (3) A case report that proposes choking as an alternative explanation for the death of a child diagnosed with abusive head trauma includes omissions and misrepresentations of facts. (4) There was a decision by the editor of the journal that published the case report that it was not necessary to include all the facts of the case; moreover, the editor indicated that facts are not required when presenting an alternative explanation. The use of scientifically unsupported alternative explanations for abusive head trauma based on inaccurate and biased information constitutes further victimization of the abused child and represents a travesty of justice. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

[Stress-induced changes of attention during choking in judo].

PubMed

Raschka, C; Mangold, R

2005-12-01

The aim of the investigation is the registration and analysis of cognitive parameters in the alarm phase of the stress reaction during a conventional judo cross choking technique. 57 judoka (41 males, 16 females; mean age 23.1 +/- 6.7 years) underwent a standardized cross-choking maneuvre (juji-jime), which lasted for 6 - 8 s until giving up, carried out by a black belt physician. The Stroop inference test was performed before and twice after the intervention. The reading velocity of the interference task was reduced by an average of 77.4 s to a mean of 74.4 s (p < 0.01), and the number of reading errors decreased by a mean from 2.9 to 2.1 (p < 0.01), finally increasing to 2.4 s. The data show the most important improvement in performance in 25 s after choking in the male judoka. In the female judoka increasing performance started already 25 s before choking and continued 25 s after the intervention. The alarm reaction following the potential life threatening stressor with an attack upon the throat improves selective attention before (female subjects) and after choking (female and male subjects) depending on gender.

Health risks of Oregon eighth-grade participants in the "choking game": results from a population-based survey.

PubMed

Ramowski, Sarah K; Nystrom, Robert J; Rosenberg, Kenneth D; Gilchrist, Julie; Chaumeton, Nigel R

2012-05-01

To examine the risk behaviors associated with participation in the "choking game" by eighth-graders in Oregon. We obtained data from the 2009 Oregon Healthy Teens survey, a cross-sectional weighted survey of 5348 eighth-graders that questioned lifetime prevalence and frequency of choking game participation. The survey also included questions about physical and mental health, gambling, sexual activity, nutrition, physical activity/body image, exposure to violence, and substance use. Lifetime prevalence of choking game participation was 6.1% for Oregon eighth-graders, with no differences between males and females. Of the eighth-grade choking game participants, 64% had engaged in the activity more than once and 26.6% >5 times. Among males, black youth were more likely to participate than white youth. Among both females and males, Pacific Islander youth were much more likely to participate than white youth. Multivariate logistic regression revealed that sexual activity and substance use were significantly associated with choking game participation for both males and females. At >6%, the prevalence of choking game participation among Oregon youth is consistent with previous findings. However, we found that most of those who participate will put themselves at risk more than once. Participants also have other associated health risk behaviors. The comprehensive adolescent well visit, as recommended by the American Academy of Pediatrics, is a good opportunity for providers to conduct a health behavior risk assessment and, if appropriate, discuss the dangers of engaging in this activity.

Meanline Analysis of Turbines with Choked Flow in the Object-Oriented Turbomachinery Analysis Code

NASA Technical Reports Server (NTRS)

Hendricks, Eric S.

2016-01-01

The Object-Oriented Turbomachinery Analysis Code (OTAC) is a new meanline/streamline turbomachinery modeling tool being developed at NASA GRC. During the development process, a limitation of the code was discovered in relation to the analysis of choked flow in axial turbines. This paper describes the relevant physics for choked flow as well as the changes made to OTAC to enable analysis in this flow regime.

Magnetic resonance conditional paramagnetic choke for suppression of imaging artifacts during magnetic resonance imaging.

PubMed

Wu, Kevin J; Gregory, T Stan; Boland, Brian L; Zhao, Wujun; Cheng, Rui; Mao, Leidong; Tse, Zion Tsz Ho

2018-06-01

Higher risk patient populations require continuous physiological monitoring and, in some cases, connected life-support systems, during magnetic resonance imaging examinations. While recently there has been a shift toward wireless technology, some of the magnetic resonance imaging devices are still connected to the outside using cabling that could interfere with the magnetic resonance imaging's radio frequency during scanning, resulting in excessive heating. We developed a passive method for radio frequency suppression on cabling that may assist in making some of these devices magnetic resonance imaging compatible. A barrel-shaped strongly paramagnetic choke was developed to suppress induced radio frequency signals which are overlaid onto physiological monitoring leads during magnetic resonance imaging. It utilized a choke placed along the signal lines, with a gadolinium solution core. The choke's magnetic susceptibility was modeled, for a given geometric design, at increasing chelate concentration levels, and measured using a vibrating sample magnetometer. Radio frequency noise suppression versus frequency was quantified with network-analyzer measurements and tested using cabling placed in the magnetic resonance imaging scanner. Temperature-elevation and image-quality reduction due to the device were measured using American Society for Testing and Materials phantoms. Prototype chokes with gadolinium solution cores exhibited increasing magnetic susceptibility, and insertion loss (S21) also showed higher attenuation as gadolinium concentration increased. Image artifacts extending <4 mm from the choke were observed during magnetic resonance imaging, which agreed well with the predicted ∼3 mm artifact from the electrochemical machining simulation. An accompanying temperature increase of <1 °C was observed in the magnetic resonance imaging phantom trial. An effective paramagnetic choke for radio frequency suppression during magnetic resonance imaging was developed and its performance demonstrated.

Basic and Applied Studies of the RAM Accelerator as a Hypervelocity Projectile Launcher

DTIC Science & Technology

1993-12-10

The quasi-steady, one-dimensional "blackbox" model of thermally choked ram accelerator performance 18 that has been widely used by the authors and...the thermal choke point is assumed to be in equilibrium, the conditions can be determined by an equilibrium chemistry combustion routine. This model ...to operation, the details of the flow field must be examined. I The simplest model of the thermally choked ram accelerator flow field treats the flow

Intrapulmonary aquaporin-5 expression as a possible biomarker for discriminating smothering and choking from sudden cardiac death: a pilot study.

PubMed

Wang, Qi; Ishikawa, Takaki; Michiue, Tomomi; Zhu, Bao-Li; Guan, Da-Wei; Maeda, Hitoshi

2012-07-10

The diagnosis of mechanical asphyxia as a cause of death, especially smothering and choking lacking evident injury, is one of the most difficult tasks in forensic pathology. The present study investigated the intrapulmonary expressions of aquaporins (AQPs; AQP-1 and AQP-5), as markers of water homeostasis, in forensic autopsy cases (total n=64, within 48 h postmortem) of mechanical asphyxiation due to neck compression (strangulation, n=24), including manual/ligature strangulation (n=12) and atypical hanging (n=12), smothering (n=7) and choking (n=8), compared with sudden cardiac death (n=14) and acute brain injury (n=11). Quantification of mRNA using a Taqman real-time PCR assay system demonstrated suppressed expression of AQP-5, but not AQP-1, in smothering and choking, compared with that in strangulation as well as sudden cardiac death and acute brain injury death. Immunostaining of AQP-5 was weakly detected in a linear pattern in the type I alveolar epithelial cells in smothering and choking cases, while cardiac and brain injury death showed marked positivity, and most strangulation cases had AQP-5-positive granular aggregates and fragments in intra-alveolar spaces. These observations indicate a partial difference in pulmonary molecular pathology among these causes of death, suggesting a procedure for possible discrimination of smothering and choking from sudden cardiac death. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

The bright and choked gamma-ray burst contribution to the IceCube and ANTARES low-energy excess

NASA Astrophysics Data System (ADS)

Denton, Peter B.; Tamborra, Irene

2018-04-01

The increasing statistics of the high-energy neutrino flux observed by the IceCube Observatory points towards an excess of events above the atmospheric neutrino background in the 30–400 TeV energy range. Such an excess is compatible with the findings of the ANTARES Telescope and it would naturally imply the possibility that more than one source class contributes to the observed flux. Electromagnetically hidden sources have been invoked to interpret this excess of events at low energies. By adopting a unified model for the electromagnetically bright and choked gamma-ray bursts and taking into account particle acceleration at the internal and collimation shock radii, we discuss whether bright and choked bursts are viable candidates. Our findings suggest that, although producing a copious neutrino flux, choked and bright astrophysical jets cannot be the dominant sources of the excess of neutrino events. A fine tuning of the model parameters or distinct scenarios for choked jets should be invoked in order to explain the low-energy neutrino data of IceCube and ANTARES.

Choking Prevention

MedlinePlus

... Hazard Items Keep items that are choking hazards away from babies and young children. These include: Coins ... to a younger child. Keep the following foods away from children younger than 4 years: Hot dogs ...

Design of Choking Cascade Turns.

DTIC Science & Technology

1982-12-01

L D-R124 792 DESIGN OF CHOK~ING CASCADE TURNSCU) AIR FORCE INST OF v TECH MRIGHT-PAT1TERSON AFB OH SCHOOL OF ENGINEERING J BAIRD DEC 82 AFIT/GRE/AA...82D- 3 DESIGN OF CHOKING *’ CASCADE TURNS THESIS Presented to the Faculty of the School of Enqineerinq of the Air Force Institute of Technoloqy Air ...Approved for public release; distribution unlimited 4* Preface Ramjet engines are being considered by both the Air Force and Navy for tactical air

Combustion Dynamics Behavior in a Single-Element Lean Direct Injection (LDI) Gas Turbine Combustor

DTIC Science & Technology

2014-06-01

Constant mass inflow from a choked orifice Exit Boundary Condition Choked nozzle Diameter of combustor 50.8 mm Diameter of air plenum 25.4 mm A...schematic of the LDI combustor is shown in Fig. 1. It comprises an air inlet section, air plenum, swirler- venturi- injector assembly, combustion chamber...and exit nozzle . Air, heated with an 80 kW electrical heater, enters the combustor through a slotted choked orifice plate, designed to minimize

Numerical Simulations of Flowfields in a Central-Dump Ramjet Combustor. 3. Effects of Chemistry

DTIC Science & Technology

1990-07-23

conditions [1,8]. The choked outflow conditions force the flow to become sonic at the throat of the exit nozzle. The choked outflow conditions force...are realistic because under most operating conditions in practical systems, the flow is choked at the throat of the exit nozzle. Furthermore, it has...timesteps in the early stages of the reactive flow case. The mixture is ignited at the end of timestep 160000. sTrEP .I070 160000 -Z ~ ~ - 36 828

Assessment of choke valve erosion in a high-pressure, high-temperature gas condensate well using TLA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Birchenough, P.M.; Cornally, D.; Dawson, S.G.B.

1994-12-31

Many planned new developments in the North Sea will involve the exploitation of hostile high pressure, high temperature gas condensate reserves. The extremely high pressure letdown over the wellhead choke leads to very high flow velocities, and consequent risks of erosion damage occurring to the choke internals. In a recent study, measurements of erosion have been performed during an offshore well test under flowing conditions using advanced Thin Layer Activation techniques and scaled Laboratory tests.

Choking - infant under 1 year

MedlinePlus

... coughing Soft or high-pitched sounds while inhaling First Aid Do NOT perform these steps if the infant ... see it. DO NOT DO NOT perform choking first aid if the infant is coughing forcefully, has a ...

Variation with Mach Number of Static and Total Pressures Through Various Screens

NASA Technical Reports Server (NTRS)

Adler, Alfred A

1946-01-01

Tests were conducted in the Langley 24-inch highspeed tunnel to ascertain the static-pressure and total-pressure losses through screens ranging in mesh from 3 to 12 wires per inch and in wire diameter from 0.023 to 0.041 inch. Data were obtained from a Mach number of approximately 0.20 up to the maximum (choking) Mach number obtainable for each screen. The results of this investigation indicate that the pressure losses increase with increasing Mach number until the choking Mach number, which can be computed, is reached. Since choking imposes a restriction on the mass rate of flow and maximum losses are incurred at this condition, great care must be taken in selecting the screen mesh and wire dimmeter for an installation so that the choking Mach number is

A case of choking phobia: towards a conceptual approach.

PubMed

Lopes, Rui; Melo, Raquel; Curral, Rosário; Coelho, Rui; Roma-Torres, António

2014-03-01

Choking phobia, also known as phagophobia or swallowing phobia is an uncommon clinical entity that has been underappreciated and is included in the new DSM-5 and upcoming ICD-11 diagnostic category of avoidant/restrictive food intake disorder. Phenomenologically distinct from other eating disorders, it is characterized by the phobic stimulus of swallowing that results in the avoidance of food or drinks, and ultimately to low weight, social withdrawal, anxiety and depression states. Its prevalence and long-term course on the general population still needs to be determined, probably reflecting years of indefiniteness regarding its nosology and by the absence of a clear set of diagnostic criteria. We present a clinical case of choking phobia in a 32-year-old male patient after an episode of choke when eating chicken. An early diagnosis and distinction from other eating disorders is important for proper treatment and fundamental for prognosis. We also make a thorough revision on literature in clinical features, differential diagnosis and treatment approaches, suggesting a conceptual approach for choking phobia as a clinical spectrum settled by different degrees of phobic subtypes, which may depend on a varied number of clinical variables.

30 CFR 250.444 - What are the choke manifold requirements?

Code of Federal Regulations, 2010 CFR

2010-07-01

... OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations... abrasiveness of drilling fluids and well fluids that you may encounter. (b) Choke manifold components must have...

Photonic Choke-Joints for Dual-Polarization Waveguides

NASA Technical Reports Server (NTRS)

Wollack, Edward J.; U-yen, Kongpop; Chuss, David T.

2010-01-01

Photonic choke joint (PCJ) structures for dual-polarization waveguides have been investigated for use in device and component packaging. This interface enables the realization of a high performance non-contacting waveguide joint without degrading the in-band signal propagation properties. The choke properties of two tiling approaches, symmetric square Cartesian and octagonal quasi-crystal lattices of metallic posts, are explored and optimal PCJ design parameters are presented. For each of these schemes, the experimental results for structures with finite tilings demonstrate near ideal transmission and reflection performance over a full waveguide band.

Food choking hazards in children.

PubMed

Sidell, Douglas R; Kim, Irene A; Coker, Tumaini R; Moreno, Candice; Shapiro, Nina L

2013-12-01

To review the literature on pediatric food choking risks, with the long-term goal of supporting legislation regulating the production, labeling, and distribution of high-risk foods. A PubMed search (Keywords: choking, obstruction, asphyxiation, foreign body, food) was conducted in July-September 2010 with publication dates ranging from 1966 to 2010. Articles related to pediatric foreign body aspiration (FBA) were selected by three independent reviewers. 1145 articles were initially identified. Abstracts were then screened utilizing a tool designed to isolate relevant pediatric choking events; this tool helped to only select abstracts which presented data on patients younger than 18 years of age who had choked on food items. Through this, a total of 72 pertinent articles were isolated (55 observational studies, 17 case reports/series). For each study, patient age, sex, foreign body location, presenting signs and symptoms, utility of radiographic studies, and type of foreign body detected in the majority of study participants were determined. A "majority" of patients for each study was predetermined arbitrarily to be 2/3 of the studied population. The majority of patients in each observational study was determined to be: male (87% of all studies) and age <5 years (95% of all studies). Aspirated foreign bodies were mostly detected in the right main bronchus foreign body (72% of all studies), and there were abnormal radiographic signs (81% of all studies) at the time of evaluation. Food-object foreign bodies were the most frequent factors associated with choking (94% of all studies). Childhood aspiration of food-objects is a significant public health issue. Although there is substantial legislation regulating non-food items that pose a choking hazard, equivalent guidelines do not exist for high-risk foods. Our study identifies and confirms several risk factors for pediatric FBA events. In doing so, it echoes the concerns and suggestions of various groups in supporting the development of legislation which may reduce the incidence of food-object aspiration. Copyright © 2013. Published by Elsevier Ireland Ltd.

A system shift in tidal choking due to the construction of Yangshan Harbour, Shanghai, China

NASA Astrophysics Data System (ADS)

Guo, Wenyun; Wang, Xiao Hua; Ding, Pingxing; Ge, Jianzhong; Song, Dehai

2018-06-01

Tidal choking is a geometric feature caused by a narrowed channel. Construction of the Yangshan Harbour, Shanghai, China obstructed three key channels and intensively changed the local geometry and topography. In this study nine numerical experiments based on the Finite-Volume Community Ocean Model are conducted to study the project's influence on tidal characteristics. Results show that stronger tidal choking happened at the East Entrance after project, mainly due to the jet induced water-level drop forced by Bernoulli law and the longer and narrower geometry. The stronger tidal choking forces a faster flow and larger tidal energy flux at the choked channel while reducing the tidal amplitude in the Inner Harbour Area (IHA). The scouring on this channel reduces the choking effect but further enlarges tidal energy flux. Moreover, damming the channels decrease the tidal amplitude at the lee side of tidal propagating direction while increasing the amplitude on the stoss side. The dams also decrease the tidal current on both sides, and meanwhile develop two patches with stronger current aside the dam. The project induced changes in tidal characteristics are complex in space, and perturbations in bathymetry increase this complexity. Yangshan Harbour's construction induces little changes in the total tidal energy density in the IHA, but induces obvious changes in the spatial distribution of tidal energy. Although this study is site-specific, the findings may be applicable to tidal dynamics in land reclamation close to open seas, such as the dramatic reclamation of islands in the South China Sea.

Semi-actuator disk theory for compressor choke flutter

NASA Technical Reports Server (NTRS)

Micklow, J.; Jeffers, J.

1981-01-01

A mathematical anaysis predict the unsteady aerodynamic utilizing semi actuator theory environment for a cascade of airfoils harmonically oscillating in choked flow was developed. A normal shock is located in the blade passage, its position depending on the time dependent geometry, and pressure perturbations of the system. In addition to shock dynamics, the model includes the effect of compressibility, interblade phase lag, and an unsteady flow field upstream and downstream of the cascade. Calculated unsteady aerodynamics were compared with isolated airfoil wind tunnel data, and choke flutter onset boundaries were compared with data from testing of an F100 high pressure compressor stage.

A Very Unusual Accidental Mechanical Asphyxia of Choking with a Whole Solea Solea.

PubMed

Busardò, Francesco Paolo; Mannocchi, Giulio; Pugnetti, Paola; Santurro, Alessandro; Maggiordomo, Aldo; Zaami, Simona

2017-03-01

The case here reported involves a schizophrenic 19-year-old girl under treatment with clotiapine, which was well tolerated except for a moderate dry mouth. The woman ingested a whole sole (Solea solea), which caused a very rapid death by choking. A complete autopsy was performed 24 h later, as well as histological and toxicological analysis. At autopsy, the sole was wedged in the esophagus causing a choking ab extrinseco. The fish had a length of 18 cm and a maximum width of 6 cm, weighing 188.7 g. Toxicological analysis detected 0.57 mg/L of clotiapine in blood, which falls within the therapeutic range. The peculiarity of this case is represented by two factors: one is the choking by fish and the second was the adverse affect caused by clotiapine, which induced a condition of dry mouth making the act of swallowing even more difficult, thereby contributing to a very rapid mechanical asphyxia and the death of the young woman. © 2016 American Academy of Forensic Sciences.

Two-phase choked flow of cryogenic fluids in converging-diverging nozzles

NASA Technical Reports Server (NTRS)

Simoneau, R. J.; Hendricks, R. C.

1979-01-01

Data are presented for the two phase choked flow of three cryogenic fluids - nitrogen, methane, and hydrogen - in four converging-diverging nozzles. The data cover a range of inlet stagnation conditions, all single phase, from well below to well above the thermodynamic critical conditions. In almost all cases the nozzle throat conditions were two phase. The results indicate that the choked flow rates were not very sensitive to nozzle geometry. However, the axial pressure profiles, especially the throat pressure and the point of vaporization, were very sensitive to both nozzle geometry and operating conditions. A modified Henry-Fauske model correlated all the choked flow rate data to within + or - 10 percent. Neither the equilibrium model nor the Henry-Fauske model predicted throat pressures well over the whole range of data. Above the thermodynamic critical temperature the homogeneous equilibrium model was preferred for both flow rate and pressure ratio. The data of the three fluids could be normalized by the principle of corresponding states.

Effects of Multiple Nozzles on Asymmetric Ejector Performance

NASA Technical Reports Server (NTRS)

Lineberry, D.; Landrum, B.

2005-01-01

This paper presents a comparison of a single nozzle and a dual nozzle strut based ejector. The results are focused on the fluid properties in the ejector duct. The research focused on choking mechanisms, mass flow entrainment, and mixing duct pressure distributions. The two ejectors were tests at equivalent primary mass flow rates. This corresponds to chamber pressures ranging from 100 psi to 900 psi in the single nozzle strut and 50 psi to 450 psi in the dual nozzle strut. Secondary flow was drawn from the lab at atmospheric pressure, and was not controlled. The secondary flow was found to choke at a value of 2.3 lb/s for a primary mass flow rate at approximately 2.1 lb/s for both ejectors. This choke was believed to be a mass addition choke rather than a traditional aerodynamic choke. The mixing duct pressure distribution exhibited two distinct trends at "low pressure" trend and at "high pressure" trend. For the low pressure trend, the mixing length for the ejectors remained fixed around 20 inches, regardless of the chamber pressure. For the higher pressure trend, the mixing length was considerably longer and increased with increasing chamber pressure. At high chamber pressures (high mass flow rates), a supersonic core flow was present at the exit of the duct. For these cases, the two streams did not have time to mix by the end of the duct.

Predictors of Asphyxiation Risk in Adults with Intellectual Disabilities and Dysphagia

ERIC Educational Resources Information Center

Samuels, R.; Chadwick, D. D.

2006-01-01

Background: Adults with learning disabilities referred for assessment of their eating and drinking are frequently reported to cough and choke when eating and drinking. The research literature investigating dysphagia has often overlooked asphyxiation risk, highlighting coughing and choking as indicators of aspiration only. This is a notable…

78 FR 28865 - Request for Comment on the Federal Guidelines for Opioid Treatment

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-16

..., Room 7-1044, Rockville, MD 20857. Please allow sufficient time for mailed comments to be received... Federal Register Representative, Division of Pharmacologic Therapies, 1 Choke Cherry Road, Room 7-1044... Representative, Division of Pharmacologic Therapies, 1 Choke Cherry Road, Room 7-1044, Rockville, MD 20850. To...

Care Staff Perceptions of Choking Incidents: What Details Are Reported?

ERIC Educational Resources Information Center

Guthrie, Susan; Lecko, Caroline; Roddam, Hazel

2015-01-01

Background: Following a series of fatal choking incidents in one UK specialist service, this study evaluated the detail included in incident reporting. This study compared the enhanced reporting system in the specialist service with the national reporting and learning system. Methods: Eligible reports were selected from a national organization and…

Multipacting-free quarter-wavelength choke joint design for BNL SRF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, W.; Belomestnykh, S.; Ben-Zvi, I.

The BNL SRF gun cavity operated well in CW mode up to 2 MV. However, its performance suffered due to multipacting in the quarter-wavelength choke joint. A new multipacting-free cathode stalk was designed and conditioned. This paper describes RF and thermal design of the new cathode stalk and its conditioning results.

Reduction of resonant RF heating in intravascular catheters using coaxial chokes.

PubMed

Ladd, M E; Quick, H H

2000-04-01

The incorporation of RF coils into the tips of intravascular devices has been shown to enable the localization of catheters and guidewires under MR guidance. Furthermore, such coils can be used for endoluminal imaging. The long cable required to connect the coil with the scanner input inadvertently acts as a dipole antenna which picks up RF energy from the body coil during transmit. Currents are induced on the cable which can lead to localized heating of surrounding tissue. Cables of various lengths were measured to determine if a resonance in the heating as a function of cable length could be found. Coaxial chokes with a length of lambda/4 were added to coaxial cables to reduce the amplitude of the currents induced on the cable shield. A 0.7-mm diameter triaxial cable, small enough to fit into a standard intravascular device, was developed and measured both with and without a coaxial choke. It is demonstrated that resonant heating does occur and that it can be significantly reduced by avoiding a resonant length of cable and by including coaxial chokes on the cable.

Constraining high-energy neutrino emission from choked jets in stripped-envelope supernovae

NASA Astrophysics Data System (ADS)

Senno, Nicholas; Murase, Kohta; Mészáros, Peter

2018-01-01

There are indications that γ-ray dark objects such as supernovae (SNe) with choked jets, and the cores of active galactic nuclei may contribute to the diffuse flux of astrophysical neutrinos measured by the IceCube observatory. In particular, stripped-envelope SNe have received much attention since they are capable of producing relativistic jets and could explain the diversity in observations of collapsar explosions (e.g., gamma-ray bursts (GRBs), low-luminosity GRBs, and Type Ibc SNe). We use an unbinned maximum likelihood method to search for spatial and temporal coincidences between Type Ibc core-collapse SNe, which may harbor a choked jet, and muon neutrinos from a sample of IceCube up-going track-like events measured from May 2011–May 2012. In this stacking analysis, we find no significant deviation from a background-only hypothesis using one year of data, and are able to place upper limits on the total amount of isotropic equivalent energy that choked jet core-collapse SNe deposit in cosmic rays Script Ecr and the fraction of core-collapse SNe which have a jet pointed towards Earth fjet. This analysis can be extended with yet to be made public IceCube data, and the increased amount of optically detected core-collapse SNe discovered by wide field-of-view surveys such as the Palomar Transient Factory and All-Sky Automated Survey for Supernovae. The choked jet SNe/high-energy cosmic neutrino connection can be more tightly constrained in the near future.

27 CFR 53.61 - Imposition and rates of tax.

Code of Federal Regulations, 2012 CFR

2012-04-01

... set of sights (iron or optical), sight mount or set of sight mounts, a choke, a flash hider, a muzzle brake, a magazine, a set of sling swivels, and/or an attachable ramrod for muzzle loading firearms when... sights and mounts, recoil pads, slings, sling swivels, chokes, and flash hiders/muzzle brakes of a type...

When Errors Count: An EEG Study on Numerical Error Monitoring under Performance Pressure

ERIC Educational Resources Information Center

Schillinger, Frieder L.; De Smedt, Bert; Grabner, Roland H.

2016-01-01

In high-stake tests, students often display lower achievements than expected based on their skill level--a phenomenon known as choking under pressure. This imposes a serious problem for many students, especially for test-anxious individuals. Among school subjects, mathematics has been shown to be particularly vulnerable to choking. To succeed in a…

Choking under Pressure: When an Additional Positive Stereotype Affects Performance for Domain Identified Male Mathematics Students

ERIC Educational Resources Information Center

Rosenthal, Harriet E. S.; Crisp, Richard J.

2007-01-01

This research aimed to establish if the presentation of two positive stereotypes would result in choking under pressure for identified male mathematics students. Seventy-five 16 year old men, who had just commenced their AS-level study, were either made aware of their gender group membership (single positive stereotype), their school group…

Microwave heating apparatus and method

DOEpatents

Johnson, Andrew J.; Petersen, Robert D.; Swanson, Stephen D.

1990-01-01

An apparatus is provided for heating and melting materials using microwave energy, and for permitting them to solidify. The apparatus includes a microwave energy source, a resonant cavity having an opening in its floor, a microwave energy choke encompassing the opening in the floor of the cavity, a metal container to hold the materials to be heated and melted, a turntable, and a lift-table. During operation, the combined action of the turntable and the lift-table position the metal container so that the top of the container is level with the floor of the cavity, is in substantial registration with the floor opening, and is encompassed by the microwave energy choke; thus, during operation, the interior of the container defines part of the resonant cavity. Additionally, a screw feeder, extending into the cavity and sheltered from microwave energy by a conveyor choke, may convey the materials to be heated to the container. Also, preferably, the floor of the resonant cavity may include perforatins, so that the offgases and dust generated in the apparatus may be removed from the resonant cavity by pulling outside air between the container choke and the exterior wall of the container into the resonant cavity and out from the cavity through the perforations.

Initiation of combustion in the thermally choked ram accelerator

NASA Technical Reports Server (NTRS)

Bruckner, A. P.; Burnham, E. A.; Knowlen, C.; Hertzberg, A.; Bogdanoff, D. W.

1992-01-01

The methodology for initiating stable combustion in a ram accelerator operating in the thermally choked mode is presented in this paper. The ram accelerator is a high velocity ramjet-in-tube projectile launcher whose principle of operation is similar to that of an airbreathing ramjet. The subcaliber projectile travels supersonically through a stationary tube filled with a premixed combustible gas mixture. In the thermally choked propulsion mode subsonic combustion takes place behind the base of the projectile and leads to thermal choking, which stabilizes a normal shock system on the projectile, thus producing forward thrust. Projectiles with masses in the 45-90 g range have been accelerated to velocities up to 2650 m/sec in a 38 mm bore, 16 m long accelerator tube. Operation of the ram accelerator is started by injecting the projectile into the accelerator tube at velocities in the 700 - 1300 m/sec range by means of a conventional gas gun. A specially designed obturator, which seals the bore of the gun during this initial acceleration, enters the ram accelerator together with the projectile. The interaction of the obturator with the propellant gas ignites the gas mixture and establishes stable combustion behind the projectile.

Emergency management of chemical weapons injuries.

PubMed

Anderson, Peter D

2012-02-01

The potential for chemical weapons to be used in terrorism is a real possibility. Classes of chemical weapons include nerve agents, vesicants (blister agents), choking agents, incapacitating agents, riot control agents, blood agents, and toxic industrial chemicals. The nerve agents work by blocking the actions of acetylcholinesterase leading to a cholinergic syndrome. Nerve agents include sarin, tabun, VX, cyclosarin, and soman. The vesicants include sulfur mustard and lewisite. The vesicants produce blisters and also damage the upper airways. Choking agents include phosgene and chlorine gas. Choking agents cause pulmonary edema. Incapacitating agents include fentanyl and its derivatives and adamsite. Riot control agents include Mace and pepper spray. Blood agents include cyanide. The mechanism of toxicity for cyanide is blocking oxidative phosphorylation. Toxic industrial chemicals include agents such as formaldehyde, hydrofluoric acid, and ammonia.

Direct Machining of Low-Loss THz Waveguide Components With an RF Choke.

PubMed

Lewis, Samantha M; Nanni, Emilio A; Temkin, Richard J

2014-12-01

We present results for the successful fabrication of low-loss THz metallic waveguide components using direct machining with a CNC end mill. The approach uses a split-block machining process with the addition of an RF choke running parallel to the waveguide. The choke greatly reduces coupling to the parasitic mode of the parallel-plate waveguide produced by the split-block. This method has demonstrated loss as low as 0.2 dB/cm at 280 GHz for a copper WR-3 waveguide. It has also been used in the fabrication of 3 and 10 dB directional couplers in brass, demonstrating excellent agreement with design simulations from 240-260 GHz. The method may be adapted to structures with features on the order of 200 μm.

Terminal-shock and restart control of a Mach 2.5, axisymmetric, mixed compression inlet with 40 percent internal contraction. [wind tunnel tests

NASA Technical Reports Server (NTRS)

Baumbick, R. J.

1974-01-01

Results of experimental tests conducted on a supersonic, mixed-compression, axisymmetric inlet are presented. The inlet is designed for operation at Mach 2.5 with a turbofan engine (TF-30). The inlet was coupled to either a choked orifice plate or a long duct which had a variable-area choked exit plug. Closed-loop frequency responses of selected diffuser static pressures used in the terminal-shock control system are presented. Results are shown for Mach 2.5 conditions with the inlet coupled to either the choked orifice plate or the long duct. Inlet unstart-restart traces are also presented. High-response inlet bypass doors were used to generate an internal disturbance and also to achieve terminal-shock control.

"Choking Game" Yields Varying Responses from Educators: Some Fear Addressing the Dangerous Activity Could Prompt Copycats

ERIC Educational Resources Information Center

Samuels, Christina A.

2006-01-01

A spate of deaths among young people around the country in the past year has brought further media attention to an asphyxial activity known as "the choking game." But the subject is a sensitive one for schools. Some administrators have actively enlisted in efforts to inform students and parents about the risks of practices like the…

Pressure distribution in a converging-diverging nozzle during two-phase choked flow of subcooled nitrogen

NASA Technical Reports Server (NTRS)

Simoneau, R. J.

1975-01-01

Choked flow rates and axial pressure distributions were measured for subcooled nitrogen in a converging-diverging nozzle with a constant area section in the throat region. Stagnation pressures ranged from slightly above saturation to twice the thermodynamic critical pressure. Stagnation temperatures ranged from 0.75 to 1.03 times the thermodynamic critical temperature. The choking plane is at the divergence end of the constant area throat section. At high stagnation pressures the fluid stays liquid well into the constant area throat region; at near saturation stagnation pressures it appears that vaporization occurs at or before the entrance to the constant area throat region. The throat-to-stagnation pressure ratio data exhibits an anomalous flat region, and this anomaly is related to the two-phase process. The fluid is metastably all liquid below the saturation pressure.

A 915-MHz antenna for microwave thermal ablation treatment: physical design, computer modeling and experimental measurement.

PubMed

Pisa, S; Cavagnaro, M; Bernardi, P; Lin, J C

2001-05-01

A 915-MHz antenna design that produces specific absorption rate distributions with preferential power deposition in tissues surrounding and including the distal end of the catheter antenna is described. The design features minimal reflected microwave current from the antenna flowing up the transmission line. This cap-choke antenna consists of an annular cap and a coaxial choke which matches the antenna to the coaxial transmission line. The design minimizes heating of the coaxial cable and its performance is not affected by the depth of insertion of the antenna into tissue. The paper provides a comparison of results obtained from computer modeling and experimental measurements made in tissue equivalent phantom materials. There is excellent agreement between numerical modeling and experimental measurement. The cap-choke, matched-dipole type antenna is suitable for intracavitary microwave thermal ablation therapy.

Neutrinos from Choked Jets Accompanied by Type-II Supernovae

NASA Astrophysics Data System (ADS)

He, Hao-Ning; Kusenko, Alexander; Nagataki, Shigehiro; Fan, Yi-Zhong; Wei, Da-Ming

2018-04-01

The origin of the IceCube neutrinos is still an open question. Upper limits from diffuse gamma-ray observations suggest that the neutrino sources are either distant or hidden from gamma-ray observations. It is possible that the neutrinos are produced in jets that are formed in core-collapsing massive stars and fail to break out, the so-called choked jets. We study neutrinos from the jets choked in the hydrogen envelopes of red supergiant stars. Fast photo-meson cooling softens the neutrino spectrum, making it hard to explain the PeV neutrinos observed by IceCube in a one-component scenario, but a two-component model can explain the spectrum. Furthermore, we predict that a newly born jet-driven type-II supernova may be observed to be associated with a neutrino burst detected by IceCube.

IR signature study of aircraft engine for variation in nozzle exit area

NASA Astrophysics Data System (ADS)

Baranwal, Nidhi; Mahulikar, Shripad P.

2016-01-01

In general, jet engines operate with choked nozzle during take-off, climb and cruise, whereas unchoking occurs while landing and taxiing (when engine is not running at full power). Appropriate thrust in an aircraft in all stages of the flight, i.e., take-off, climb, cruise, descent and landing is achieved through variation in the nozzle exit area. This paper describes the effect on thrust and IR radiance of a turbojet engine due to variation in the exit area of a just choked converging nozzle (Me = 1). The variations in the nozzle exit area result in either choking or unchoking of a just choked converging nozzle. Results for the change in nozzle exit area are analyzed in terms of thrust, mass flow rate and specific fuel consumption. The solid angle subtended (Ω) by the exhaust system is estimated analytically, for the variation in nozzle exit area (Ane), as it affects the visibility of the hot engine parts from the rear aspect. For constant design point thrust, IR radiance is studied from the boresight (ϕ = 0°, directly from the rear side) for various percentage changes in nozzle exit area (%ΔAne), in the 1.9-2.9 μm and 3-5 μm bands.

Fluid-structure interaction analysis and lifetime estimation of a natural gas pipeline centrifugal compressor under near-choke and near-surge conditions

NASA Astrophysics Data System (ADS)

Ju, Yaping; Liu, Hui; Yao, Ziyun; Xing, Peng; Zhang, Chuhua

2015-11-01

Up to present, there have been no studies concerning the application of fluid-structure interaction (FSI) analysis to the lifetime estimation of multi-stage centrifugal compressors under dangerous unsteady aerodynamic excitations. In this paper, computational fluid dynamics (CFD) simulations of a three-stage natural gas pipeline centrifugal compressor are performed under near-choke and near-surge conditions, and the unsteady aerodynamic pressure acting on impeller blades are obtained. Then computational structural dynamics (CSD) analysis is conducted through a one-way coupling FSI model to predict alternating stresses in impeller blades. Finally, the compressor lifetime is estimated using the nominal stress approach. The FSI results show that the impellers of latter stages suffer larger fluctuation stresses but smaller mean stresses than those at preceding stages under near-choke and near-surge conditions. The most dangerous position in the compressor is found to be located near the leading edge of the last-stage impeller blade. Compressor lifetime estimation shows that the investigated compressor can run up to 102.7 h under the near-choke condition and 200.2 h under the near-surge condition. This study is expected to provide a scientific guidance for the operation safety of natural gas pipeline centrifugal compressors.

Cavitation in flow through a micro-orifice inside a silicon microchannel

NASA Astrophysics Data System (ADS)

Mishra, Chandan; Peles, Yoav

2005-01-01

Hydrodynamic cavitation in flows through a micro-orifice entrenched in a microchannel has been detected and experimentally investigated. Microfabrication techniques have been employed to design and develop a microfluidic device containing an 11.5μm wide micro-orifice inside a 100.2μm wide and 101.3μm deep microchannel. The flow of de-ionized water through the micro-orifice reveals the presence of multifarious cavitating flow regimes. This investigation divulges both similarities and differences between cavitation in micro-orifices and cavitation in their macroscale counterparts. The low incipient cavitation number obtained from the current experiments suggests a dominant size scale effect. Choking cavitation is observed to be independent of any pressure or velocity scale effects. However, choking is significantly influenced by the small stream nuclei residence time at such scales. Flow rate choking leads to the establishment of a stationary cavity. Large flow and cavitation hysteresis have been detected at the microscale leading to very high desinent cavitation numbers. The rapid transition from incipient bubbles to choking cavitation and subsequent supercavitation suggests the presence of radically different flow patterns at the microscale. Supercavitation results in a thick cavity, which extends throughout the microchannel, and is encompassed by the liquid. Cavitation at the microscale is expected to considerably influence the design of innovative high-speed microfluidic systems.

System for pressure letdown of abrasive slurries

DOEpatents

Kasper, Stanley

1991-01-01

A system and method for releasing erosive slurries from containment at high pressure without subjecting valves to highly erosive slurry flow. The system includes a pressure letdown tank disposed below the high-pressure tank, the two tanks being connected by a valved line communicating the gas phases and a line having a valve and choke for a transfer of liquid into the letdown tank. The letdown tank has a valved gas vent and a valved outlet line for release of liquid. In operation, the gas transfer line is opened to equalize pressure between tanks so that a low level of liquid flow occurs. The letdown tank is then vented, creating a high-pressure differential between the tanks. At this point, flow between tanks is controlled by the choke. High-velocity, erosive flow through a high-pressure outlet valve is prevented by equalizing the start up pressure and thereafter limiting flow with the choke.

Identification and Analysis of National Airspace System Resource Constraints

NASA Technical Reports Server (NTRS)

Smith, Jeremy C.; Marien, Ty V.; Viken, Jeffery K.; Neitzke, Kurt W.; Kwa, Tech-Seng; Dollyhigh, Samuel M.; Fenbert, James W.; Hinze, Nicolas K.

2015-01-01

This analysis is the deliverable for the Airspace Systems Program, Systems Analysis Integration and Evaluation Project Milestone for the Systems and Portfolio Analysis (SPA) focus area SPA.4.06 Identification and Analysis of National Airspace System (NAS) Resource Constraints and Mitigation Strategies. "Identify choke points in the current and future NAS. Choke points refer to any areas in the en route, terminal, oceanic, airport, and surface operations that constrain actual demand in current and projected future operations. Use the Common Scenarios based on Transportation Systems Analysis Model (TSAM) projections of future demand developed under SPA.4.04 Tools, Methods and Scenarios Development. Analyze causes, including operational and physical constraints." The NASA analysis is complementary to a NASA Research Announcement (NRA) "Development of Tools and Analysis to Evaluate Choke Points in the National Airspace System" Contract # NNA3AB95C awarded to Logistics Management Institute, Sept 2013.

Multipacting simulation and test results of BNL 704 MHz SRF gun

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu W.; Belomestnykh, S.; Ben-Zvi, I.

The BNL 704MHz SRF gun has a grooved choke joint to support the photo-cathode. Due to the distortion of grooves at the choke joint during the BCP for the choke joint, several multipacting barriers showed up when it was tested with Nb cathode stalk at JLab. We built a setup to use the spare large grain SRF cavity to test and condition the multipacting at BNL with various power sources up to 50kW. The test is carried out in three stages: testing the cavity performance without cathode, testing the cavity with the Nb cathode stalk that was used at Jlab,more » and testing the cavity with a copper cathode stalk that is based on the design for the SRF gun. This paper summarizes the results of multipacting simulation, and presents the large grain cavity test setup and the test results.« less

The Choking Game on YouTube: An Update.

PubMed

Defenderfer, Ellen K; Austin, Jillian E; Davies, W Hobart

2016-01-01

The choking game (TCG) is an adolescent activity in which asphyxiation is used to obtain a "high," occasionally resulting in seizures or death. A plethora of TCG information is available through YouTube, though this content has not been evaluated recently. The current study described TCG as portrayed in YouTube videos and compared views and ratings of TCG videos to unrelated videos. The TCG videos demonstrated diverse methods of asphyxiation, with a minority showing injury to the participants. TCG videos were less likely to be commented on or rated positively than non-choking game videos. TCG prevention videos differed significantly from actual TCG videos in the way they depicted the social context of TCG. Thus, TCG videos are accessible through YouTube, but the prevention materials available on YouTube are not accurate or representative. Accurate and educational online prevention materials should be created to decrease the occurrence of TCG.

Choking under social pressure: social monitoring among the lonely.

PubMed

Knowles, Megan L; Lucas, Gale M; Baumeister, Roy F; Gardner, Wendi L

2015-06-01

Lonely individuals may decode social cues well but have difficulty putting such skills to use precisely when they need them--in social situations. In four studies, we examined whether lonely people choke under social pressure by asking participants to complete social sensitivity tasks framed as diagnostic of social skills or nonsocial skills. Across studies, lonely participants performed worse than nonlonely participants on social sensitivity tasks framed as tests of social aptitude, but they performed just as well or better than the nonlonely when the same tasks were framed as tests of academic aptitude. Mediational analyses in Study 3 and misattribution effects in Study 4 indicate that anxiety plays an important role in this choking effect. This research suggests that lonely individuals may not need to acquire social skills to escape loneliness; instead, they must learn to cope with performance anxiety in interpersonal interactions. © 2015 by the Society for Personality and Social Psychology, Inc.

Quasi-one-dimensional compressible flow across face seals and narrow slots. 1: Analysis

NASA Technical Reports Server (NTRS)

Zuk, J.; Ludwig, L. P.; Johnson, R. L.

1972-01-01

An analysis is presented for compressible fluid flow across shaft face seals and narrow slots. The analysis includes fluid inertia, viscous friction, and entrance losses. Subsonic and choked flow conditions can be predicted and analyzed. The model is valid for both laminar and turbulent flows. Results agree with experiment and with solutions which are more limited in applicability. Results show that a parallel film can have a positive film stiffness under choked flow conditions.

Photonic Waveguide Choke Joint with Absorptive Loading

NASA Technical Reports Server (NTRS)

Wollack, Edward J. (Inventor); U-Yen, Kongpop (Inventor); Chuss, David T. (Inventor)

2016-01-01

A photonic waveguide choke includes a first waveguide flange member having periodic metal tiling pillars, a dissipative dielectric material positioned within an area between the periodic metal tiling pillars and a second waveguide flange member disposed to be coupled with the first waveguide flange member and in spaced-apart relationship separated by a gap. The first waveguide flange member has a substantially smooth surface, and the second waveguide flange member has an array of two-dimensional pillar structures formed therein.

Single-Cylinder Oil-Control Tests of Porous Chrome-Plated Cylinder Barrels for Radial Air-Cooled Engines

DTIC Science & Technology

1946-01-01

plating, it will affect a choke as desired in the cylinder. When the clearance between the anode and the cathode (cylinder barrel) is decreased, an...National Advisory Commltteo for Aeronautics, Cltivel« oid , Ohio. RSFEFKICE3 1. Johnson, Robert L., wad Anderson, Roy I.: S.’.nglo-Cylindor Engine Tests...plating a choke in the bore. Choice la obtained by decreasing the clear- ance between the anode and the cylinder barrel ( cathode ). Taper on anode la

[Strangulation marks in homicides caused by choking ? On an irritant blood stain picture].

PubMed

Metter, D

1988-01-01

Three homicides and one attempted homicide by choking in which apparent signs of throttling were present on the skin of the neck are described. The victims wore slender necklaces which were pressed against the skin by the hands of the perpetrator, causing transverse hematomas and cutaneous abrasions. The following criterious are typical for simulated signs of throttling: similarity to objects on the neck, incomplete course around the neck, absence of coarctation of the soft tissues, no lesions of subcutaneous structures.

Application of the principle of corresponding states to two phase choked flow

NASA Technical Reports Server (NTRS)

Hendricks, R. C.; Simoneau, R. J.

1973-01-01

It is pointed out that several fluids including methane, oxygen, and nitrogen appear to form an average parametric plot which indicates that the isenthalpic Joule-Thomson coefficient must nearly obey the principle of corresponding states. With this as a basis, it was assumed that there could be several thermodynamic flow processes which nearly obey the principle. An examination was made to determine whether two-phase choked flow could be one of them. The analysis is described and the results are given.

Waveguide Photonic Choke Joint with Wide Out-of-Band Rejection

NASA Technical Reports Server (NTRS)

U-yen, Kongpop; Wollack, Edward J.

2015-01-01

A photonic choke joint structure with a wide-stop-band is proposed for use as a waveguide flange interface. The structure consists of arrays of square metal pillars arranged in a periodic pattern to suppress the dominant-mode wave propagation in parallel-plate waveguide over a wide frequency bandwidth. The measurement results at microwave frequencies confirm that the structure can provide broadband suppression of more than 56dB over 6.25 times its operating frequency. Applications at millimeter wavelength are discussed.

Waveguide Photonic Choke Joint with Wide Out-of-Band Rejection

NASA Technical Reports Server (NTRS)

U-yen, Kongpop; Wollack, Edward J.

2015-01-01

A photonic choke joint structure with a wide- stop-band is proposed for use as a waveguide flange interface. The structure consists of arrays of square metal pillars arranged in a periodic pattern to suppress the dominant-mode wave propagation in parallel-plate waveguide over a wide frequency bandwidth. The measurement results at microwave frequencies confirm the structure can provide broadband suppression, more than 56 dB over 6.25 times its operating frequency. Applications at millimeter wavelength are discussed.

61. VIEW LOOKING NORTHWEST AT A SIGNAL REACTOR OR CHOKE ...

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

61. VIEW LOOKING NORTHWEST AT A SIGNAL REACTOR OR CHOKE COIL. WITHIN THE PROTECTIVE ENCLOSURE IS AN AIR AND PORCELAIN INSULATED COIL OF 5/8' DIAMETER STRANDED COPPER WIRE. REACTOR COILS WERE PLACED IN SERIES WITH EACH LEG OF THREE PHASE GENERATORS. THEIR FUNCTION WAS TO MODERATE SURGES OF CURRENT CAUSED BY LIGHTNING STRIKES, OPEN OR SHORT CIRCUIT PROBLEMS ON THE LINE. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

Hysteria, or "suffocation of the mother".

PubMed Central

Merskey, H; Merskey, S J

1993-01-01

OBJECTIVE: To understand or explain the surprising adherence of prominent physicians throughout the centuries to terms suggesting that the womb could move and cause suffocation, choking or difficulty in swallowing. DATA SOURCES: Hippocratic writings on hysterical symptoms and the views of subsequent authors and contexts surrounding such views. DATA SYNTHESIS: Physicians who followed Hippocrates repeatedly related difficulties in breathing or choking and difficulties in swallowing to the uterus, although most recognized that the womb did not rise out of the pelvis, except partially, when enlarged by pregnancy. Respiratory and gastrointestinal symptoms were often associated with anxiety. The effects may have been attributed to the womb, because it was recognized that the womb, when enlarged, can cause difficulty in breathing. Anxiety was also reported more often in women and may have been attributed to the womb for that reason. CONCLUSION: The suffocation of the mother can be understood as anxiety with dyspnea, and globus hystericus reflects anxiety with a choking sensation or difficulty in swallowing. PMID:8439911

Loss of Arctic sea ice causing punctuated change in sightings of killer whales (Orcinus orca) over the past century.

PubMed

Higdon, Jeff W; Ferguson, Steven H

2009-07-01

Killer whales (Orcinus orca) are major predators that may reshape marine ecosystems via top-down forcing. Climate change models predict major reductions in sea ice with the subsequent expectation for readjustments of species' distribution and abundance. Here, we measure changes in killer whale distribution in the Hudson Bay region with decreasing sea ice as an example of global readjustments occurring with climate change. We summarize records of killer whales in Hudson Bay, Hudson Strait, and Foxe Basin in the eastern Canadian Arctic and relate them to an historical sea ice data set while accounting for spatial and temporal autocorrelation in the data. We find evidence for "choke points," where sea ice inhibits killer whale movement, thereby creating restrictions to their Arctic distribution. We hypothesize that a threshold exists in seasonal sea ice concentration within these choke points that results in pulses in advancements in distribution of an ice-avoiding predator. Hudson Strait appears to have been a significant sea ice choke point that opened up .approximately 50 years ago allowing for an initial punctuated appearance of killer whales followed by a gradual advancing distribution within the entire Hudson Bay region. Killer whale sightings have increased exponentially and are now reported in the Hudson Bay region every summer. We predict that other choke points will soon open up with continued sea ice melt producing punctuated predator-prey trophic cascades across the Arctic.

Analytical study of pressure balancing in gas film seals

NASA Technical Reports Server (NTRS)

Zuk, J.

1973-01-01

The load factor is investigated for subsonic and choked flow conditions, laminar and turbulent flows, and various seal entrance conditions. Both parallel sealing surfaces and surfaces with small linear deformation were investigated. The load factor for subsonic flow depends strongly on pressure ratio; under choked flow conditions, however the load factor is found to depend more strongly on film thickness and flow entrance conditions rather than pressure ratio. The importance of generating hydrodynamic forces to keep the seal balanced under severe and multipoint operation is also discussed.

[Recommendations for the prevention of organic foreign bodies aspiration].

PubMed

Rodríguez, Hugo; Cuestas, Giselle; Gregori, Darío; Lorenzoni, Giulia; Tortosa, Susana; Rodríguez D'Aquila, Máximo; Rodríguez D'Aquila, Juan A; Carrera, Sandra; Passali, Desiderio

2017-10-01

Foreign body aspiration remains a common and potentially serious pediatric problem. Most aspirated foreign bodies are food. The education of parents and caregivers about choking hazards and how to avoid them is critical to reduce the incidence of these events. The pediatricians play a key role in promoting injury prevention. We indicate the main characteristics of hazardous food and we present recommendations on age-appropriate meals, adequate forms of food preparation and behavioral rules at mealtimes in order to reduce food choking. Sociedad Argentina de Pediatría.

Computer program for quasi-one-dimensional compressible flow with area change and friction - Application to gas film seals

NASA Technical Reports Server (NTRS)

Zuk, J.; Smith, P. J.

1974-01-01

A computer program is presented for compressible fluid flow with friction and area change. The program carries out a quasi-one-dimensional flow analysis which is valid for laminar and turbulent flows under both subsonic and choked flow conditions. The program was written to be applied to gas film seals. The area-change analysis should prove useful for choked flow conditions with small mean thickness, as well as for face seals where radial area change is significant. The program is written in FORTRAN 4.

Proceedings of the NATO Advanced Study Institute on High-Brightness Accelerators Held in Pitlochry, Scotland on 13-25 July 1986. Series B. Volume 178

DTIC Science & Technology

1986-07-25

parasites (trichinosis) Improvement in technological properties of food HIGH DOSE (10-50 kGy) Sterilization for commercial purposes Elimination of viruses ...instance, D37 equals 30-80 Gy for Eschercheria coli, 1 kGy for bacillus mesentericus spores, and 4 kGy for tobacco mosaic virus (Casarett, 1968...HF CHOKE CORONA SHIEL DS9 RF ELECTRODE ACCELERATING CHAMBER L j RF CHOKE I RESONANT COIL Fig. 16. Principle of operation: the Dynamitron. of insulator

The quiet revolution: continuous glider monitoring at ocean 'choke' points as a key component of new cross-platform ocean observation systems

NASA Astrophysics Data System (ADS)

Heslop, E. E.; Tintore, J.; Ruiz, S.; Allen, J.; López-Jurado, J. L.

2014-12-01

A quiet revolution is taking place in ocean observations; in the last decade new multi-platform, integrated ocean observatories have been progressively implemented by forward looking countries with ocean borders of economic and strategic importance. These systems are designed to fill significant gaps in our knowledge of the ocean state and ocean variability, through long-term, science and society-led, ocean monitoring. These ocean observatories are now delivering results, not the headline results of a single issue experiment, but carefully and systematically improving our knowledge of ocean variability, and thereby, increasing model forecast skill and our ability to link physical processes to ecosystem response. Here we present the results from a 3-year quasi-continuous glider monitoring of a key circulation 'choke' point in the Western Mediterranean, undertaken by SOCIB (Balearic Islands Coastal Ocean Observing and Forecasting System). For the first time data from the high frequency glider sampling show variations in the transport volumes of water over timescales of days to weeks, as large as those previously only identifiable as seasonal or eddy driven. Although previous surveys noted high cruise-to-cruise variability, they were insufficient to show that in fact water volumes exchanged through this narrow 'choke' point fluctuate on 'weather' timescales. Using the glider data to leverage an 18-year record of ship missions, we define new seasonal cycles for the exchange of watermasses, challenging generally held assumptions. The pattern of the exchange is further simplified through the characterisation of 5 circulation modes and the defining of a new seasonal cycle for the interplay between mesoscale and basin scale dynamics. Restricted 'choke points' between our ocean basins are critical locations to monitor water transport variability, as they constrain the inter-basin exchange of heat, salt and nutrients. At the Ibiza Channel 'choke' point, the exchange of watermass is known to affect local ecosystems, including the spawning grounds of commercially important fish stocks, at a biodiversity hotspot. This new insight will be vital in improving our ocean model forecast skill and in the development of integrated ocean products for society.

Unravelling relationships: Hospital occupancy levels, discharge timing and emergency department access block.

PubMed

Khanna, Sankalp; Boyle, Justin; Good, Norm; Lind, James

2012-10-01

To investigate the effect of hospital occupancy levels on inpatient and ED patient flow parameters, and to simulate the impact of shifting discharge timing on occupancy levels. Retrospective analysis of hospital inpatient data and ED data from 23 reporting public hospitals in Queensland, Australia, across 30 months. Relationships between outcome measures were explored through the aggregation of the historic data into 21 912 hourly intervals. Main outcome measures included admission and discharge rates, occupancy levels, length of stay for admitted and emergency patients, and the occurrence of access block. The impact of shifting discharge timing on occupancy levels was quantified using observed and simulated data. The study identified three stages of system performance decline, or choke points, as hospital occupancy increased. These choke points were found to be dependent on hospital size, and reflect a system change from 'business-as-usual' to 'crisis'. Effecting early discharge of patients was also found to significantly (P < 0.001) impact overcrowding levels and improve patient flow. Modern hospital systems have the ability to operate efficiently above an often-prescribed 85% occupancy level, with optimal levels varying across hospitals of different size. Operating over these optimal levels leads to performance deterioration defined around occupancy choke points. Understanding these choke points and designing strategies around alleviating these flow bottlenecks would improve capacity management, reduce access block and improve patient outcomes. Effecting early discharge also helps alleviate overcrowding and related stress on the system. © 2012 CSIRO. EMA © 2012 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

A Case Study of Hypnosis for Phagophobia: It's No Choking Matter.

PubMed

Reid, David B

2016-04-01

In this case study the author reviews the benefits of hypnosis for a 13-year-old female suffering from a specific phobia involving a fear of choking and generalized fear of swallowing that resulted in an episode of Restrictive Food Intake Disorder with associated significant weight loss. At the time of the initial consultation, three weeks after her choking episode, the patient weighed 93 pounds. Standing at 5'2", her Body Mass Index (BMI) was 17 (15th percentile) indicative of healthy weight for a child her age and height. She continued to lose weight over the course of 2 months and at her worst weighed 85 pounds (BMI = 15.5, 3rd percentile, classified as underweight). Prior to the incident, she weighed 105 pounds with a BMI of 19.2 (46th percentile). Treatment initially consisted of 12 hypnosis sessions (over a 5-month period), conducted on a weekly and eventually biweekly basis. A scheduled one-month follow-up visit was conducted following the 12th session, at which time the patient was consuming solid foods without fear of choking. Her BMI at that time was 18.7 (39th percentile). Two months after terminating treatment, the patient experienced a mild relapse triggered by conflicts with some female peers. After four additional hypnosis sessions, the patient's symptoms again remitted. During her last session we shared a pizza, providing clear and convincing evidence that she had overcome her fear of swallowing. She retained therapeutic benefits for at least 3 years following treatment.

Unusual case of choking due to assassin bug ( Cydnocoris gilvus).

PubMed

Sonar, Vaibhav; Patil, Sachin

2018-01-01

Choking is a form of asphyxia which is caused by an obstruction within the air passages. Here, we report a case of obstruction of the upper respiratory tract due to assassin bug ( Cydnocoris gilvus) where allegations of medical negligence were made by relatives of the deceased. Autopsy findings demonstrated that an insect was present inside the larynx, lodged at the epiglottis. Multiple haemorrhagic patches were present at the base of the tongue, larynx, epiglottis, vocal cords and tracheal bifurcation. As Reduviidae can be successfully used as a biological pest-control agents, they should be used with due precaution.

Intensification and refraction of acoustical signals in partially choked converging ducts

NASA Technical Reports Server (NTRS)

Nayfeh, A. H.

1980-01-01

A computer code based on the wave-envelope technique is used to perform detailed numerical calculations for the intensification and refraction of sound in converging hard walled and lined circular ducts carrying high mean Mach number flows. The results show that converging ducts produce substantial refractions toward the duct center for waves propagating against near choked flows. As expected, the magnitude of the refraction decreases as the real part of the admittance increases. The pressure wave pattern is that of interference among the different modes, and hence the variation of the magnitude of pressure refraction with frequency is not monotonic.

Measurements of Thermal Effects on Acoustic Screech in a Choked Circular Jet Emanating from a Sharp-Edged Orifice

NASA Technical Reports Server (NTRS)

Kandula, Max

2012-01-01

Experiments are performed in a 24.4 mm diameter choked circular hot and cold jets issuing from a sharp-edged orifice at a fully expanded jet Mach number of 1.85. The stagnation temperature of the hot and the cold jets are 319 K and 299 K respectively. The results suggest that temperature effects on the screech amplitude and frequency are manifested for the fundamental, with a reduced amplitude and increased frequency for hot jet relative to the cold jet. Temperature effects on the second harmonic are also observed.

Correlation of Gastroesophageal reflux disease Assessment Symptom Questionnaire to impedance-pH measurements in children.

PubMed

Prachuapthunyachart, Sittichoke; Jarasvaraparn, Chaowapong; Gremse, David A

2017-01-01

Esophageal multichannel intraluminal impedance-pH monitoring has become one of the preferred tests to correlate observed reflux-like behaviors with esophageal reflux events. The Gastroesophageal reflux disease Assessment Symptom Questionnaire is a validated tool used to distinguish infants with gastroesophageal reflux disease from healthy children. The aim of this study was to determine whether the Gastroesophageal reflux disease Assessment Symptom Questionnaire composite symptom scores and individual symptom scores correlate with outcomes in esophageal multichannel intraluminal impedance-pH monitoring. A total of 26 patients with gastroesophageal reflux disease-associated symptoms, aged 0-2 years, for whom both esophageal multichannel intraluminal impedance-pH monitoring and Gastroesophageal reflux disease Assessment Symptom Questionnaire survey results were available were included in the study. Gastroesophageal reflux disease Assessment Symptom Questionnaire score data were collected from a 7-day recall of parent's responses about the frequency and severity of gastroesophageal reflux disease symptoms, which determined the individual symptom scores. The composite symptom scores is the sum of all individual symptom scores. Multichannel intraluminal impedance-pH study results were compared to Gastroesophageal reflux disease Assessment Symptom Questionnaire data using Pearson correlation. Among 26 patients, a total number of 2817 (1700 acid and 1117 non-acid) reflux episodes and 845 clinical reflux behaviors were recorded. There were significant correlations between the reflux index and the individual symptom scores for coughing/gagging/choking (r 2 = 0.2842, p = 0.005), the impedance score and individual symptom scores for coughing/gagging/choking (r 2 = 0.2482, p = 0.009), the reflux symptom index for acid reflux-related coughing/gagging/choking and the individual symptom scores for coughing/gagging/choking (r 2 = 0.1900, p = 0.026), the impedance score and individual symptom scores for vomiting (r 2 = 0.1569, p = 0.045), and the impedance score and the composite symptom scores (r 2 = 0.2916, p = 0.004). However, there were no significant correlations between fussiness, irritability, or abdominal pain-related multichannel intraluminal impedance-pH results and the individual symptom scores for abdominal pain. The impedance scores from multichannel intraluminal impedance-pH studies correlate with coughing/gagging/choking and vomiting in infants with gastroesophageal reflux disease. There are no significant correlations among the reflux index and impedance score versus the Gastroesophageal reflux disease Assessment Symptom Questionnaire scores for abdominal pain. We conclude that in infants with gastroesophageal reflux disease, multichannel intraluminal impedance-pH studies are more likely to demonstrate an association between gastroesophageal reflux disease and symptoms of coughing, gagging, or choking compared to an association between gastroesophageal reflux disease and pain in infants.

Correlation of Gastroesophageal reflux disease Assessment Symptom Questionnaire to impedance-pH measurements in children

PubMed Central

Prachuapthunyachart, Sittichoke; Jarasvaraparn, Chaowapong; Gremse, David A

2017-01-01

Background: Esophageal multichannel intraluminal impedance-pH monitoring has become one of the preferred tests to correlate observed reflux-like behaviors with esophageal reflux events. The Gastroesophageal reflux disease Assessment Symptom Questionnaire is a validated tool used to distinguish infants with gastroesophageal reflux disease from healthy children. The aim of this study was to determine whether the Gastroesophageal reflux disease Assessment Symptom Questionnaire composite symptom scores and individual symptom scores correlate with outcomes in esophageal multichannel intraluminal impedance-pH monitoring. Methods: A total of 26 patients with gastroesophageal reflux disease–associated symptoms, aged 0–2 years, for whom both esophageal multichannel intraluminal impedance-pH monitoring and Gastroesophageal reflux disease Assessment Symptom Questionnaire survey results were available were included in the study. Gastroesophageal reflux disease Assessment Symptom Questionnaire score data were collected from a 7-day recall of parent’s responses about the frequency and severity of gastroesophageal reflux disease symptoms, which determined the individual symptom scores. The composite symptom scores is the sum of all individual symptom scores. Multichannel intraluminal impedance-pH study results were compared to Gastroesophageal reflux disease Assessment Symptom Questionnaire data using Pearson correlation. Results: Among 26 patients, a total number of 2817 (1700 acid and 1117 non-acid) reflux episodes and 845 clinical reflux behaviors were recorded. There were significant correlations between the reflux index and the individual symptom scores for coughing/gagging/choking (r2 = 0.2842, p = 0.005), the impedance score and individual symptom scores for coughing/gagging/choking (r2 = 0.2482, p = 0.009), the reflux symptom index for acid reflux-related coughing/gagging/choking and the individual symptom scores for coughing/gagging/choking (r2 = 0.1900, p = 0.026), the impedance score and individual symptom scores for vomiting (r2 = 0.1569, p = 0.045), and the impedance score and the composite symptom scores (r2 = 0.2916, p = 0.004). However, there were no significant correlations between fussiness, irritability, or abdominal pain–related multichannel intraluminal impedance-pH results and the individual symptom scores for abdominal pain. Conclusion: The impedance scores from multichannel intraluminal impedance-pH studies correlate with coughing/gagging/choking and vomiting in infants with gastroesophageal reflux disease. There are no significant correlations among the reflux index and impedance score versus the Gastroesophageal reflux disease Assessment Symptom Questionnaire scores for abdominal pain. We conclude that in infants with gastroesophageal reflux disease, multichannel intraluminal impedance-pH studies are more likely to demonstrate an association between gastroesophageal reflux disease and symptoms of coughing, gagging, or choking compared to an association between gastroesophageal reflux disease and pain in infants. PMID:29276590

A closed-form analytical model for predicting 3D boundary layer displacement thickness for the validation of viscous flow solvers

NASA Astrophysics Data System (ADS)

Kumar, V. R. Sanal; Sankar, Vigneshwaran; Chandrasekaran, Nichith; Saravanan, Vignesh; Natarajan, Vishnu; Padmanabhan, Sathyan; Sukumaran, Ajith; Mani, Sivabalan; Rameshkumar, Tharikaa; Nagaraju Doddi, Hema Sai; Vysaprasad, Krithika; Sharan, Sharad; Murugesh, Pavithra; Shankar, S. Ganesh; Nejaamtheen, Mohammed Niyasdeen; Baskaran, Roshan Vignesh; Rahman Mohamed Rafic, Sulthan Ariff; Harisrinivasan, Ukeshkumar; Srinivasan, Vivek

2018-02-01

A closed-form analytical model is developed for estimating the 3D boundary-layer-displacement thickness of an internal flow system at the Sanal flow choking condition for adiabatic flows obeying the physics of compressible viscous fluids. At this unique condition the boundary-layer blockage induced fluid-throat choking and the adiabatic wall-friction persuaded flow choking occur at a single sonic-fluid-throat location. The beauty and novelty of this model is that without missing the flow physics we could predict the exact boundary-layer blockage of both 2D and 3D cases at the sonic-fluid-throat from the known values of the inlet Mach number, the adiabatic index of the gas and the inlet port diameter of the internal flow system. We found that the 3D blockage factor is 47.33 % lower than the 2D blockage factor with air as the working fluid. We concluded that the exact prediction of the boundary-layer-displacement thickness at the sonic-fluid-throat provides a means to correctly pinpoint the causes of errors of the viscous flow solvers. The methodology presented herein with state-of-the-art will play pivotal roles in future physical and biological sciences for a credible verification, calibration and validation of various viscous flow solvers for high-fidelity 2D/3D numerical simulations of real-world flows. Furthermore, our closed-form analytical model will be useful for the solid and hybrid rocket designers for the grain-port-geometry optimization of new generation single-stage-to-orbit dual-thrust-motors with the highest promising propellant loading density within the given envelope without manifestation of the Sanal flow choking leading to possible shock waves causing catastrophic failures.

Powder fed sheared dispersal particle generator

NASA Technical Reports Server (NTRS)

Morrisette, E. L.; Bushnell, D. M. (Inventor)

1984-01-01

A particle generating system is described which is capable of breaking up agglomerations of particles and producing a cloud of uniform, submicron-sized particles at high pressure and high flow rates. This is achieved by utilizing a tubular structure which has injection microslits on is periphery to accept and disperse the desired particle feed. By suppling a carrying fluid at a pressure, of approximately twice the ambient pressure of the velocimeter's settling chamber, the microslits operate at choked flow conditions. The shearing action of this choked flow is sufficient to overcome interparticle bonding forces, thereby breaking up the agglomerates of the particles feed into individual particles.

Exploring the Properties of Choked Gamma-ray Bursts with IceCube’s High-energy Neutrinos

NASA Astrophysics Data System (ADS)

Denton, Peter B.; Tamborra, Irene

2018-03-01

Long duration gamma-ray bursts (GRBs) have often been considered the natural evolution of some core-collapse supernova (CCSN) progenitors. However, the fraction of CCSNe linked to astrophysical jets and their properties are still poorly constrained. While any successful astrophysical jet harbored in a CCSN should produce high-energy neutrinos, photons may be able to successfully escape the stellar envelope only for a fraction of progenitors, possibly leading to the existence of high-luminosity, low-luminosity, and not-electromagnetically bright (“choked”) GRBs. By postulating a CCSN–GRB connection, we accurately model the jet physics within the internal-shock GRB model and assume scaling relations for the GRB parameters that depend on the Lorentz boost factor Γ. The IceCube high-energy neutrino flux is then employed as an upper limit of the neutrino background from electromagnetically bright and choked GRBs to constrain the jet and the progenitor properties. The current IceCube data set is compatible with up to 1% of all CCSNe harboring astrophysical jets. Interestingly, those jets are predominantly choked. Our findings suggest that neutrinos can be powerful probes of the burst physics and can provide major insights on the CCSN–GRB connection.

Why do English players fail in soccer penalty shootouts? A study of team status, self-regulation, and choking under pressure.

PubMed

Jordet, Geir

2009-01-15

I examine why players from some nations appear always to choke in major international soccer penalty shootouts. Based on a model on choking under pressure as a type of self-defeating behaviour (Baumeister, 1997), I hypothesized that highly favourable public appraisals of a team would be linked to displays of escapist self-regulation strategies and inferior performance. I selected the eight most merited European nations, obtained videos from penalty shootouts in two major international tournaments (World Cup and European Championships), and analysed all 200 shots taken by players representing these teams. The results showed significant relationships between team status, self-regulation strategies, and performance. Players from countries that, at the time of the penalty shootout, either had many international club titles or featured many internationally decorated players, spent less time preparing their shots and were less successful from the penalty spot than players from countries with lower public status. England and Spain are used to illustrate these effects, as the data suggest that players from these two countries may have underperformed in previous international soccer tournaments because of high public status and misguided self-regulation strategies.

Stability limits of unsteady open capillary channel flow

NASA Astrophysics Data System (ADS)

Grah, Aleksander; Haake, Dennis; Rosendahl, Uwe; Klatte, J.?Rg; Dreyer, Michael E.

This paper is concerned with steady and unsteady flow rate limitations in open capillary channels under low-gravity conditions. Capillary channels are widely used in Space technology for liquid transportation and positioning, e.g. in fuel tanks and life support systems. The channel observed in this work consists of two parallel plates bounded by free liquid surfaces along the open sides. The capillary forces of the free surfaces prevent leaking of the liquid and gas ingestion into the flow.In the case of steady stable flow the capillary pressure balances the differential pressure between the liquid and the surrounding constant-pressure gas phase. Increasing the flow rate in small steps causes a decrease of the liquid pressure. A maximum steady flow rate is achieved when the flow rate exceeds a certain limit leading to a collapse of the free surfaces due to the choking effect. In the case of unsteady flow additional dynamic effects take place due to flow rate transition and liquid acceleration. The maximum flow rate is smaller than in the case of steady flow. On the other hand, the choking effect does not necessarily cause surface collapse and stable temporarily choked flow is possible under certain circumstances.To determine the limiting volumetric flow rate and stable flow dynamic properties, a new stability theory for both steady and unsteady flow is introduced. Subcritical and supercritical (choked) flow regimes are defined. Stability criteria are formulated for each flow type. The steady (subcritical) criterion corresponds to the speed index defined by the limiting longitudinal small-amplitude wave speed, similar to the Mach number. The unsteady (supercritical) criterion for choked flow is defined by a new characteristic number, the dynamic index. It is based on pressure balances and reaches unity at the stability limit.The unsteady model based on the Bernoulli equation and the mass balance equation is solved numerically for perfectly wetting incompressible liquids. The unsteady model and the stability theory are verified by comparison to results of a sounding rocket experiment (TEXUS 41) on capillary channel flows launched in December 2005 from ESRANGE in north Sweden. For a clear overview of subcritical, supercritical, and unstable flow, parametric studies and stability diagrams are shown and compared to experimental observations.

Sound transmission in ducts containing nearly choked flows

NASA Technical Reports Server (NTRS)

Callegari, A. J.; Myers, M. K.

1979-01-01

The nonlinear theory previously developed by the authors (1977, 1978) is used to obtain numerical results for sound transmission through a nearly choked throat in a variable-area duct. Parametric studies are performed for different source locations, strengths and frequencies. It is shown that the nonlinear interactions in the throat region generate superharmonics of the fundamental (source) frequency throughout the duct. The amplitudes of these superharmonics increase as the source parameters (frequency and strength) are increased toward values leading to acoustic shocks. For a downstream source, superharmonics carry about 20% of the total acoustic power as shocking conditions are approached. For the source strength levels and frequencies considered, streaming effects are negligible.

Responding to a Choking Emergency

MedlinePlus

... Healthy Living Healthy Living Healthy Living Nutrition Fitness Sports Oral Health Emotional Wellness Growing Healthy Sleep Safety & Prevention Safety & Prevention Safety and Prevention Immunizations ...

Dysphagia is a common and serious problem for adults with mental illness: a systematic review.

PubMed

Aldridge, Kristy J; Taylor, Nicholas F

2012-03-01

Adults with mental illness may experience a higher incidence of dysphagia and choking due to factors such as medication side effects and behavioural abnormalities. The aim of this study was to determine the frequency of dysphagia and the most effective interventions for this population. Studies published up to August 2010 were sought via a comprehensive electronic database search (CINAHL, PsycINFO, MEDLINE, PubMed, Cochrane, and Embase). Studies reporting dysphagia frequency or dysphagia intervention outcomes in adults with mental illness were included. Two reviewers independently assessed study eligibility and quality, and the results were synthesised descriptively. Ten studies were identified, each describing dysphagia frequency or death due to choking asphyxiation. No studies evaluating intervention effectiveness were identified. Study quality was limited by subjective assessment of outcomes. Six studies presented dysphagia frequencies ranging from 9 to 42% in varying subgroups. Four studies presented the frequency of choking asphyxiation death, including a large survey that concluded that adults with organic mental illness were 43 times more likely to die of this cause than the general population. Dysphagia is a common and significant cause of morbidity and mortality in adults with mental illness and our review found that there is a lack of studies evaluating the effectiveness of intervention techniques.

Detailed analysis of the flow in the inducer of a transonic centrifugal compressor

NASA Astrophysics Data System (ADS)

Buffaz, Nicolas; Trébinjac, Isabelle

2012-02-01

Numerical and experimental investigations were conducted in a transonic centrifugal compressor stage composed of a backswept splittered unshrouded impeller and a vaned diffuser. A detailed analysis of the flow in the inducer (i.e. the entry zone of the impeller between the main blade leading edge and the splitter blade leading edge) is proposed from choke to surge. Steady and unsteady simulations were performed using the code elsA, which uses a multi-domain approach on structured meshes and solves the compressible RANS equations, associated with a two-equation turbulence model k-l in the rotating frame of reference. The 1MW LMFA-ECL test rig was used for carrying out the tests in the compressor stage. Unsteady pressure measurements up to 150 kHz and Laser Doppler Anemometry measurements were performed in the inducer. A good agreement is obtained between the experimental and numerical data even if an over dissipation is noticed in the numerical results. The change in flow pattern from choke to surge is mainly due to a change in the tip leakage flow trajectory which straightens, leading to a flow blockage of an individual passage near shroud. A spectral analysis shows that only the blade passing frequency and its harmonics compose the various spectra obtained from choke to surge.

How PEMEX engineered a deep well completion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Antimo A., J.C.

1971-09-01

Completion and testing of Petroleos Mexicano's W. Reynosa Well No. 1 in the NE. Frontier District south of the Texas border required engineering innovation to combat the 375/sup 0/F temperatures and pressures near 18,000 psi. Drilled to nearly 18,000 ft, the well was completed and tested below 17,000 ft. Completion plans were designed to determine the economic importance of the reservoir and to provide information and experience in planning future completions to 20,000 ft and deeper. Interval selection was based in part on data acquired during drilling, including lithology, geologic age, rock characteristics, and sensitivity to damage caused by drillingmore » fluids. A set of logs was obtained and evaluated by computer in correlation with mud-log and pressure data. The logs also were correlated with logs from other wells in the area. Pressure gradients in the Reynosa field indicated the possibility of pressures on the order of 10,000 psi, and required the use of specially designed valves rated to 20,000 psi, in conjunction with a casinghead that would permit drilling to the projected depth. A choke manifold consisted of an interchangeable, manually operated positive choke and a set of automatic adjustable chokes. Well conditioning, including cementing, perforating, and well plugging are described.« less

Congenital hairy polyp of the oropharynx presenting as an esophageal mass in a neonate, a case report and literature review.

PubMed

Richter, Amy; Mysore, Krupa; Schady, Deb; Chandy, Binoy

2016-01-01

To review the literature of congenital hairy polyps and describe the clinical presentation, operative management, and histologic findings of a congenital hairy polyp arising from the palatopharyngeus muscle in a neonate with recurrent choking episodes. Chart review of a 2-month-old male referred to a tertiary care pediatric hospital. We present a case of a 2-month-old male who presented to the emergency room with recurrent episodes of choking and vomiting. The patient was previously healthy with no prior medical or neonatal history. The parents noted a small fleshy mass in the patient's oropharynx that he would chew on and swallow after several minutes. However, on physical exam, there was no evidence of oropharyngeal mass. The patient did not have respiratory distress. Imaging revealed a 22×7×11mm oblong, fatty mass in the lower cervical and upper thoracic esophagus with a thin stalk extending proximally to the upper collapsed esophagus. Intraoperative recorded laryngoscopy revealed a pedunculated soft palate mass attached to the right superior palatopharyngeus muscle. Histopathology revealed ectodermal and mesodermal elements in a polypoid structure lined by keratinizing squamous epithelium with adnexal structures and central mature adipose tissue, consistent with congenital hairy polyp resembling an accessory tragus of the ear and branchial anomaly. At 6-week follow up, the patient was doing well and gaining weight appropriately with no further choking episodes. There was no evidence of velopharyngeal dysfunction on follow up exam. The surgical site was completely healed and there was no evidence of recurrence. Congenital hairy polyps of the naso- and oropharynx are rare but may present as airway or esophageal masses, causing respiratory distress or choking episodes in a pediatric patient. The pathologic findings of keratinizing squamous epithelium, adnexal structures, adipose and cartilage tissues resemble congenital accessory tragus and may be considered a branchial arch anomaly. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Blockage of upper airway

MedlinePlus

... or fidgeting Bluish color to the skin ( cyanosis ) Changes in consciousness Choking Confusion Difficulty breathing , gasping for air, leading to panic Unconsciousness Wheezing , crowing, whistling, or other ...

A tabulation of pipe length to diameter ratios as a function of Mach number and pressure ratios for compressible flow

NASA Technical Reports Server (NTRS)

Dixon, G. V.; Barringer, S. R.; Gray, C. E.; Leatherman, A. D.

1975-01-01

Computer programs and resulting tabulations are presented of pipeline length-to-diameter ratios as a function of Mach number and pressure ratios for compressible flow. The tabulations are applicable to air, nitrogen, oxygen, and hydrogen for compressible isothermal flow with friction and compressible adiabatic flow with friction. Also included are equations for the determination of weight flow. The tabulations presented cover a wider range of Mach numbers for choked, adiabatic flow than available from commonly used engineering literature. Additional information presented, but which is not available from this literature, is unchoked, adiabatic flow over a wide range of Mach numbers, and choked and unchoked, isothermal flow for a wide range of Mach numbers.

Suicidal choking caused by a bizarre combination of inhalation to the bronchi and external neck compression.

PubMed

Pampin, J B; Varela, L G

2001-06-01

We report a remarkable case of suicidal choking in an elderly man with depressive episodes and one previous attempt of suicide. Initially, the presence of a sweater around his neck and blunt injuries on his head, left elbow and sacrum region seemed to indicate a suspicious violent death. During the necropsy study, a fragment of newspaper was discovered inside his lower respiratory tract. Autopsy findings showed minimal punctata haemorrhages on the larynx and trachea. The subsequent toxicological investigation was negative. This case is extremely rare, because the deceased was not a schizophrenic patient and the peculiar foreign object was found in the lower level. To the best of our knowledge, in medicolegal literature, few similar cases have been reported.

Over-the-counter medicines

MedlinePlus

... throat lozenges can be soothing. Be careful in young children because of the choking risk. ALLERGIES Antihistamine pills and liquids work well for treating allergy symptoms . Antihistamines that may ...

Fatal Asphyxiation in Bottlenose Dolphins (Tursiops truncatus) from the Indian River Lagoon.

PubMed

Stolen, Megan; St Leger, Judy; Durden, Wendy Noke; Mazza, Teresa; Nilson, Erika

2013-01-01

Multiple single case reports of asphyxiation in dolphins caused by fish lodged in the esophagus exist. However, the significance of this cause of mortality in a single population has not been documented. We performed a retrospective evaluation of pathology records from stranded bottlenose dolphins (Tursiops truncatus) from the Indian River Lagoon to evaluate the impact of this cause of death on this population. From 1997 to 2011, asphyxiation due to choking was identified as the cause of death in 14 of 350 cases (4%). Sampling of an unrelated but adjacent population over this same period yielded 186 necropsy cases of bottlenose dolphins with no cases of asphyxiation. Asphyxiated animals presented with a fish lodged in the cranial esophagus associated with a dislocated and obstructed or compressed larynx. There was no clear sex predilection. Affected animals included 12 adults and two juveniles. The fish species involved included sheepshead, black chin tilapia and striped mojarra. In five cases, recreational fishing gear was also present. Cetacean choking is related to selection of prey fish species with strong dorsal spines and may be secondarily associated with fish attached to fishing gear. Prey abundance and dolphin behavior may influence these selections. Environmental alterations leading to changes in prey availability or increased interactions with fishing gear may change the significance of fatal choking in dolphin populations.

Meanline Analysis of Turbines with Choked Flow in the Object-Oriented Turbomachinery Analysis Code

NASA Technical Reports Server (NTRS)

Hendricks, Eric S.

2016-01-01

The prediction of turbomachinery performance characteristics is an important part of the conceptual aircraft engine design process. During this phase, the designer must examine the effects of a large number of turbomachinery design parameters to determine their impact on overall engine performance and weight. The lack of detailed design information available in this phase necessitates the use of simpler meanline and streamline methods to determine the turbomachinery geometry characteristics and provide performance estimates prior to more detailed CFD (Computational Fluid Dynamics) analyses. While a number of analysis codes have been developed for this purpose, most are written in outdated software languages and may be difficult or impossible to apply to new, unconventional designs. The Object-Oriented Turbomachinery Analysis Code (OTAC) is currently being developed at NASA Glenn Research Center to provide a flexible meanline and streamline analysis capability in a modern object-oriented language. During the development and validation of OTAC, a limitation was identified in the code's ability to analyze and converge turbines as the flow approached choking. This paper describes a series of changes which can be made to typical OTAC turbine meanline models to enable the assessment of choked flow up to limit load conditions. Results produced with this revised model setup are provided in the form of turbine performance maps and are compared to published maps.

75 FR 56113 - Notice of Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-15

... with the CMHS Designated Federal Official (DFO), Ms. Carol Watkins (see contact information below) to...: Carol Watkins, Designated Federal Official, CMHS National Advisory Council, 1 Choke Cherry Road, Room 6...

Thermally-Choked Combustor Technology

NASA Technical Reports Server (NTRS)

Knuth, William H.; Gloyer, P.; Goodman, J.; Litchford, R. J.

1993-01-01

A program is underway to demonstrate the practical feasibility of thermally-choked combustor technology with particular emphasis on rocket propulsion applications. Rather than induce subsonic to supersonic flow transition in a geometric throat, the goal is to create a thermal throat by adding combustion heat in a diverging nozzle. Such a device would have certain advantages over conventional flow accelerators assuming that the pressure loss due to heat addition does not severely curtail propulsive efficiency. As an aid to evaluation, a generalized one-dimensional compressible flow analysis tool was constructed. Simplified calculations indicate that the process is fluid dynamically and thermodynamically feasible. Experimental work is also being carried out in an attempt to develop, assuming an array of practical issues are surmountable, a practical bench-scale demonstrator using high flame speed H2/O2 combustibles.

Investigation of turbines for driving supersonic compressors II : performance of first configuration with 2.2 percent reduction in nozzle flow area / Warner L. Stewart, Harold J. Schum, Robert Y. Wong

NASA Technical Reports Server (NTRS)

Stewart, Warner L; Schum, Harold J; Wong, Robert Y

1952-01-01

The experimental performance of a modified turbine for driving a supersonic compressor is presented and compared with the performance of the original configuration to illustrate the effect of small changes in the ratio of nozzle-throat area to rotor-throat area. Performance is based on the performance of turbines designed to operate with both blade rows close to choking. On the basis of the results of this investigation, the ratio of areas is concluded to become especially critical in the design of turbines such as those designed to drive high-speed, high-specific weight-flow compressors where the turbine nozzles and rotor are both very close to choking.

Geodetic antenna calibration test in the Antarctic environment

USGS Publications Warehouse

Grejner-Brzezinska, A.; Vazquez, E.; Hothem, L.

2006-01-01

TransAntarctic Mountain DEFormation (TAMDEF) Monitoring Network is the NSF-sponsored OSU and USGS project, aimed at measuring crustal motion in the Transantarctic Mountains of Victoria Land using GPS carrier phase measurements. Station monumentation, antenna mounts, antenna types, and data processing strategies were optimized to achieve mm-level estimates for the rates of motion. These data contributes also to regional Antarctic frame definition. Significant amount of data collected over several years allow the investigation of unique aspects of GPS geodesy in Antarctica, to determine how the error spectrum compares to the mid-latitude regions, and to identify the optimum measurement and data processing schemes for Antarctic conditions, in order to test the predicted rates of motion (mm-level w.r.t. time). The data collection for the TAMDEF project was initiated in 1996. The primary antenna used has been the Ashtech L1/L2 Dorne Margolin (D/M) choke ring. A few occupations involved the use of a Trimble D/M choke ring. The data were processed using the antenna calibration data available from the National Geodetic Survey (NGS). The recent developments in new antenna designs that are lighter in weight and lower in cost are being considered as a possible alternative to the bulkier and more expensive D/M choke ring design. In November 2003, in situ testing of three alternative models of L1/L2 antennas was conducted at a site located in the vicinity of McMurdo Station, Antarctica (S77.87, E166.56). The antenna models used in this test were: Ashtech D/M choke ring, Trimble D/M choke ring, Trimble Zephyr, and the NovAtel GPS-702. Two stations, spaced within 30 meters, were used in the test. Both had the characteristics similar to the stations of the TAMDEF network, i.e., the UNAVCO fixed-height, force-centered level mounts with a constant antenna offset were used, ensuring extreme stability of the antenna/ mount/pin set up. During each of the four 3-day test data collection sessions, a reference station was occupied continuously with the Ashtech D/M choke ring antenna, while the second station was occupied by the tested antennas, one 3-day session for each antenna type. The coordinate differences were produced using software optimized for the analysis of data collected over short baselines. Each solution incorporated the NGS antenna calibration data appropriate for each antenna model. Hourly and 24-hour solutions were analyzed for repeatability and compared to the standard baseline coordinate differences. No significant variation was observed when comparing the same type of antennas and when switching antennas at the test site using daily solutions. An mm-level scatter can be observed comparing different antennas over the 1-hour solutions; it is smaller for the horizontal components, as compared to the vertical direction. At this point, it can be concluded that the standard antenna calibration models from NGS used for each antenna involved in this test did not result in any significant variation in the daily results, but with some in the hourly results. Thus, based on this fact, the antenna types tested here could be used in the future TAMDEF campaigns, where 24-hour solutions are normally used for deformation monitoring. These results can serve as good guidance to any future use of GPS equipment in Antarctica.

Preliminary Two-Phase Terry Turbine Nozzle Models for RCIC Off-Design Operation Conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Haihua; O'Brien, James

This report presents the effort to extend the single-phase analytical Terry turbine model to cover two-phase off-design conditions. The work includes: (1) adding well-established two-phase choking models – the Isentropic Homogenous Equilibrium Model (IHEM) and Moody’s model, and (2) theoretical development and implementation of a two-phase nozzle expansion model. The two choking models provide bounding cases for the two-phase choking mass flow rate. The new two-phase Terry turbine model uses the choking models to calculate the mass flow rate, the critical pressure at the nozzle throat, and steam quality. In the divergent stage, we only consider the vapor phase withmore » a similar model for the single-phase case by assuming that the liquid phase would slip along the wall with a much slower speed and will not contribute the impulse on the rotor. We also modify the stagnation conditions according to two-phase choking conditions at the throat and the cross-section areas for steam flow at the nozzle throat and at the nozzle exit. The new two-phase Terry turbine model was benchmarked with the same steam nozzle test as for the single-phase model. Better agreement with the experimental data is observed than from the single-phase model. We also repeated the Terry turbine nozzle benchmark work against the Sandia CFD simulation results with the two-phase model for the pure steam inlet nozzle case. The RCIC start-up tests were simulated and compared with the single-phase model. Similar results are obtained. Finally, we designed a new RCIC system test case to simulate the self-regulated Terry turbine behavior observed in Fukushima accidents. In this test, a period inlet condition for the steam quality varying from 1 to 0 is applied. For the high quality inlet period, the RCIC system behaves just like the normal operation condition with a high pump injection flow rate and a nominal steam release rate through the turbine, with the net addition of water to the primary system; for the low quality inlet period, the RCIC turbine shaft work dramatically decreases and results in a much reduced pump injection flow rate, and the mixture flow rate through the turbine increases due to the high liquid phase flow rate. The net effect for this period is net removal of coolant from the primary loop. With the periodic addition and removal of coolant to the primary loop, the self-regulation mode of the RCIC system can be maintained for a quite long time. Both the IHEM and Moody’s models generate similar phenomena; however noticeable differences can be observed.« less

Infant Choking: How to Keep Your Baby Safe

MedlinePlus

... of Privacy Practices Notice of Nondiscrimination Manage Cookies Advertising Mayo Clinic is a not-for-profit organization and proceeds from Web advertising help support our mission. Mayo Clinic does not ...

Choosing Safe Toys

MedlinePlus

... the throat above the windpipe and restrict breathing. Battery-operated toys should have battery cases that secure with screws so that kids cannot pry them open. Batteries and battery fluid pose serious risks, including choking, ...

78 FR 21891 - Rural Call Completion

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-12

... traffic may not be blocked, choked, reduced, or restricted, we have learned that carriers often do not... called party, including, for example, by voicemail, answering machine, or fax machine. We calculate a...

Key Facts about Tularemia

MedlinePlus

... Methyl isocyanate Case Definition: Methyl Isocyanate Poisoning Mustard gas (H) (sulfur mustard) Facts About Sulfur Mustard Case ... choking/lung agents Ricin Riot control agents/tear gas Facts About Riot Control Agents Case Definition: Riot ...

Choking: First Aid

MedlinePlus

... 2, 2017. Kleinman ME, et al. Part 5: Adult basic life support and cardiopulmonary resuscitation quality — 2015 American ... and Research. © 1998-2018 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved.

Demountable damped cavity for HOM-damping in ILC superconducting accelerating cavities

NASA Astrophysics Data System (ADS)

Konomi, T.; Yasuda, F.; Furuta, F.; Saito, K.

2014-01-01

We have designed a new higher-order-mode (HOM) damper called a demountable damped cavity (DDC) as part of the R&D efforts for the superconducting cavity of the International Linear Collider (ILC). The DDC has two design concepts. The first is an axially symmetrical layout to obtain high damping efficiency. The DDC has a coaxial structure along the beam axis to realize strong coupling with HOMs. HOMs are damped by an RF absorber at the end of the coaxial waveguide and the accelerating mode is reflected by a choke filter mounted at the entrance of the coaxial waveguide. The second design concept is a demountable structure to facilitate cleaning, in order to suppress the Q-slope problem in a high field. A single-cell cavity with the DDC was fabricated to test four performance parameters. The first was frequency matching between the accelerating cavity and the choke filter. Since the bandwidth of the resonance frequency in a superconducting cavity is very narrow, there is a possibility that the accelerating field will leak to the RF absorber because of thermal shrinkage. The design bandwidth of the choke filter is 25 kHz. It was demonstrated that frequency matching adjusted at room temperature could be successfully maintained at 2 K. The second parameter was the performance of the demountable structure. At the joint, the magnetic field is 1/6 of the maximum field in the accelerating cavity. Ultimately, the accelerating field reached 19 MV/m and Q0 was 1.5×1010 with a knife-edge shape. The third parameter was field emission and multipacting. Although the choke structure has numerous parallel surfaces that are susceptible to the multipacting problem, it was found that neither field emission nor multipacting presented problems in both an experiment and simulation. The final parameter was the Q values of the HOM. The RF absorber adopted in the system is a Ni-Zn ferrite type. The RF absorber shape was designed based on the measurement data of permittivity and permeability at 77 K. The Q values of the HOM in the DDC are 10-100 times lower than those of a TESLA-type HOM coupler.

First Aid: Choking

MedlinePlus

... breathing, send someone to call 911 . Immediately perform cardiopulmonary resuscitation (CPR) if you've been trained. Take your child ... reach. Learn how to do abdominal thrusts and CPR, which usually are taught as part of any ...

Choking and Strangulation Prevention Tips

MedlinePlus

... away from children. These include magnets found in construction sets, children's toys or stress-relieving adult desk ... with Us Donate Join Our Mailing List Global Road Safety Sponsors Recalls Media Center Blog Videos Newsletter ...

Choking first aid - infant under 1 year - slideshow

MedlinePlus

... Duplication for commercial use must be authorized in writing by ADAM Health Solutions. About MedlinePlus Site Map FAQs Customer Support Get email updates Subscribe to RSS Follow us Disclaimers Copyright ...

16 CFR 1501.1 - Purpose.

Code of Federal Regulations, 2010 CFR

2010-01-01

... IDENTIFYING TOYS AND OTHER ARTICLES INTENDED FOR USE BY CHILDREN UNDER 3 YEARS OF AGE WHICH PRESENT CHOKING... chapter classifies as a banned hazardous substance any toy or other article intended for use by children...

Cold Medicines for Kids: What's the Risk?

MedlinePlus

... thin secretions. Warm liquids, such as tea or chicken soup, might have a soothing effect, increase the ... harmful effects. However, hard candy is a choking hazard and shouldn't be given to younger children. ...

Choking (Heimlich Maneuver)

MedlinePlus

... a hero. Learn CPR Use “ICE” in Your Cell Phone Prepare for Disasters Communication With Your Family And ... the call and send emergency personnel to you. (Cell phone calls may not be traceable to an exact ...

Choking Prevention and Rescue Tips

MedlinePlus

... Workplace Training Driver Training First Aid Training Consulting Surveys Research Safety Topics Fatigue Drugs at Work Driving Workplace ... of an Effective Safety Management System Employee Perception Surveys Research Safety Topics Fatigue Drugs at Work Driving Workplace ...

Household Safety: Preventing Choking

MedlinePlus

... More for Teens Teens site Sitio para adolescentes Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Drugs & ... exploring are the activities that develop your child's body and mind. Reviewed by: Rupal Christine Gupta, MD Date reviewed: ...

Choking first aid - adult or child over 1 year - slideshow

MedlinePlus

... Duplication for commercial use must be authorized in writing by ADAM Health Solutions. About MedlinePlus Site Map FAQs Customer Support Get email updates Subscribe to RSS Follow us Disclaimers Copyright ...

Aeroacoustic Characteristics of Model Jet Test Facility Flow Conditioners

NASA Technical Reports Server (NTRS)

Kinzie, Kevin W.; Henderson, Brenda S.; Haskin, Harry H.

2005-01-01

An experimental investigation of flow conditioning devices used to suppress internal rig noise in high speed, high temperature experimental jet facilities is discussed. The aerodynamic and acoustic characteristics of a number of devices including pressure loss and extraneous noise generation are measured. Both aerodynamic and acoustic characteristics are strongly dependent on the porosity of the flow conditioner and the closure ratio of the duct system. For unchoked flow conditioners, the pressure loss follows conventional incompressible flow models. However, for choked flow conditioners, a compressible flow model where the duct and flow conditioner system is modeled as a convergent-divergent nozzle can be used to estimate pressure loss. Choked flow conditioners generate significantly more noise than unchoked conditioners. In addition, flow conditioners with small hole diameters or sintered metal felt material generate less self-noise noise compared to flow conditioners with larger holes.

The choking game: A deadly game. Analysis of two cases of "self-strangulation" in young boys and review of the literature.

PubMed

Re, Laura; Birkhoff, Jutta M; Sozzi, Marta; Andrello, Luisa; Osculati, Antonio M M

2015-02-01

The choking game is defined as a self-strangulation or strangulation by another person with the hands or a noose to achieve a brief euphoric state caused by cerebral hypoxia. Death may occur, but forensic pathologists often classify them as suicides or accidental deaths, without focusing on the possibility that they may result from a deliberate self-temporary-asphyxiation, turned into a deadly game. Presenting two fatal cases of self-strangulation involving an 11-year-old boy and a teenager of 15 years, the authors identify victims' characteristics and death scene's evidence, which may help to distinguish if a death is from an asphyxial suicide or an asphyxial game. Copyright © 2014 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Nonlinear theory of shocked sound propagation in a nearly choked duct flow

NASA Technical Reports Server (NTRS)

Myers, M. K.; Callegari, A. J.

1982-01-01

The development of shocks in the sound field propagating through a nearly choked duct flow is analyzed by extending a quasi-one dimensional theory. The theory is applied to the case in which sound is introduced into the flow by an acoustic source located in the vicinity of a near-sonic throat. Analytical solutions for the field are obtained which illustrate the essential features of the nonlinear interaction between sound and flow. Numerical results are presented covering ranges of variation of source strength, throat Mach number, and frequency. It is found that the development of shocks leads to appreciable attenuation of acoustic power transmitted upstream through the near-sonic flow. It is possible, for example, that the power loss in the fundamental harmonic can be as much as 90% of that introduced at the source.

Subclinical dysphagia in persons with Prader-Willi syndrome.

PubMed

Gross, Roxann Diez; Gisser, Ronit; Cherpes, Gregory; Hartman, Katie; Maheshwary, Rishi

2017-02-01

Prader-Willi Syndrome (PWS) is caused by a genetic imprinting abnormality resulting from the lack of expression of the paternal genes at 15q11-q13. Intellectual disability, low muscle tone, and life-threatening hyperphagia are hallmarks of the phenotype. The need for the Heimlich maneuver, death from choking, and pulmonary infection occur in a disproportionally high number of persons with PWS. The widely held belief is that eating behaviors are responsible for choking and aspiration; yet, no investigation had sought to determine if swallowing impairments were present in persons with PWS. To address this research and clinical gap, simultaneous videofluoroscopy and nasal respiratory signals were used to record swallowing function and breathing/swallowing coordination in 30 participants with PWS. Subjects consumed thin liquid and barium cookies under two randomized conditions as follows: (i) controlled (cues to swallow and standardized bolus sizes); (ii) spontaneous (no cues or bolus size control). Under videofluoroscopy, the cohort showed disordered pharyngeal and esophageal swallowing in both conditions with disturbances in timing, clearance, and coordination of swallowing with the respiratory cycle. No participant showed a sensory response such as attempting to clear residue or coughing; thereby supporting the lack of overt symptoms. We conclude that the high death rate from choking and pulmonary infection in children and adults with PWS may be related, in part, to underlying, asymptomatic dysphagia. The combination of rapid eating and dysphagia would increase the risk of aspiration-related morbidity and mortality. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Choking - adult or child over 1 year

MedlinePlus

... Hockberger RS, Walls RM, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ed. Philadelphia, PA: Elsevier ... Hockberger RS, Walls RM, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ed. Philadelphia, PA: Elsevier ...

16 CFR 1117.5 - Information that must be reported and to whom.

Code of Federal Regulations, 2010 CFR

2010-01-01

... SAFETY ACT REGULATIONS REPORTING OF CHOKING INCIDENTS INVOLVING MARBLES, SMALL BALLS, LATEX BALLOONS AND... (including any labeling and warnings), a description of the marble, small ball, latex balloon or other small...

End Operation Choke Point Act of 2014

THOMAS, 113th Congress

Rep. Luetkemeyer, Blaine [R-MO-3

2014-06-26

House - 07/15/2014 Hearings Held by the Subcommittee on Financial Institutions and Consumer Credit Prior to Referral. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

16 CFR 1117.4 - Time for filing a report.

Code of Federal Regulations, 2010 CFR

2010-01-01

... REPORTING OF CHOKING INCIDENTS INVOLVING MARBLES, SMALL BALLS, LATEX BALLOONS AND OTHER SMALL PARTS § 1117.4... marble, small ball, or latex balloon or on a marble, small ball, latex balloon, or other small part...

40 CFR 610.21 - Device functional category and vehicle system effects.

Code of Federal Regulations, 2012 CFR

2012-07-01

... device's category will be based on: (1) Engineering principles governing operation of the device; (2... mechanical) All. Vapor Injectors All. Choke controls 1, 2, and 4. Air filters 1, 2, and 4. Fuel-air...

40 CFR 610.21 - Device functional category and vehicle system effects.

Code of Federal Regulations, 2014 CFR

2014-07-01

... device's category will be based on: (1) Engineering principles governing operation of the device; (2... mechanical) All. Vapor Injectors All. Choke controls 1, 2, and 4. Air filters 1, 2, and 4. Fuel-air...

40 CFR 610.21 - Device functional category and vehicle system effects.

Code of Federal Regulations, 2013 CFR

2013-07-01

... device's category will be based on: (1) Engineering principles governing operation of the device; (2... mechanical) All. Vapor Injectors All. Choke controls 1, 2, and 4. Air filters 1, 2, and 4. Fuel-air...

Determining queue and congestion in highway work zone bottlenecks.

DOT National Transportation Integrated Search

2011-03-11

Construction zones, though required for infrastructure maintenance, have become congestion choke points on most highway systems in the US. The congestion may create potentially unsafe driving conditions for approaching motorists that do not expect qu...

Determining Queue and Congestion in Highway Work Zone Bottlenecks

DOT National Transportation Integrated Search

2011-03-11

Construction zones, though required for infrastructure maintenance, have become congestion choke points on most highway systems in the US. The congestion may create potentially unsafe driving conditions for approaching motorists that do not expect qu...

Swimming

MedlinePlus

... or eat while you swim — you could choke. Lakes and Ponds Lots of kids swim in streams, lakes, or ponds. Take extra care when swimming in ... can't always see the bottom of the lake or pond, so you don't always know ...

Electromagnetic interference filter for automotive electrical systems

DOEpatents

Herron, Nicholas Hayden; Carlson, Douglas S; Tang, David; Korich, Mark D

2013-07-02

A filter for an automotive electrical system includes a substrate having first and second conductive members. First and second input terminals are mounted to the substrate. The first input terminal is electrically connected to the first conductive member, and the second input terminal is electrically connected to the second conductive member. A plurality of capacitors are mounted to the substrate. Each of the capacitors is electrically connected to at least one of the first and second conductive members. First and second power connectors are mounted to the substrate. The first power connector is electrically connected to the first conductive member, and the second power connector is electrically connected to the second conductive member. A common mode choke is coupled to the substrate and arranged such that the common mode choke extends around at least a portion of the substrate and the first and second conductive members.

Unsteady Full Annulus Simulations of a Transonic Axial Compressor Stage

NASA Technical Reports Server (NTRS)

Herrick, Gregory P.; Hathaway, Michael D.; Chen, Jen-Ping

2009-01-01

Two recent research endeavors in turbomachinery at NASA Glenn Research Center have focused on compression system stall inception and compression system aerothermodynamic performance. Physical experiment and computational research are ongoing in support of these research objectives. TURBO, an unsteady, three-dimensional, Navier-Stokes computational fluid dynamics code commissioned and developed by NASA, has been utilized, enhanced, and validated in support of these endeavors. In the research which follows, TURBO is shown to accurately capture compression system flow range-from choke to stall inception-and also to accurately calculate fundamental aerothermodynamic performance parameters. Rigorous full-annulus calculations are performed to validate TURBO s ability to simulate the unstable, unsteady, chaotic stall inception process; as part of these efforts, full-annulus calculations are also performed at a condition approaching choke to further document TURBO s capabilities to compute aerothermodynamic performance data and support a NASA code assessment effort.

Team history and choking under pressure in major soccer penalty shootouts.

PubMed

Jordet, Geir; Hartman, Esther; Vuijk, Pieter Jelle

2012-05-01

This study examined the links between historical team results and individual players' subsequent performances in a high-pressure real-world sport situation. Videos were obtained from all soccer penalty shootouts held in two major international tournaments (World Cup and European Championships) between 1976 and 2006 (n=260 players/309 kicks), and we controlled for team ability and country. The results showed that players on teams with preceding losses performed worse and generally took their shots more quickly than players on teams with preceding wins. These differences were also found with players who took no personal part in the preceding games. In conclusion, the results support the existence of historical dependency effects for performance on important and dramatic high-pressure tasks and they are in part consistent with a view of choking under pressure as a function of threatened egotism and self-regulation failure. ©2011 The British Psychological Society.

The choking game and YouTube: a dangerous combination.

PubMed

Linkletter, Martha; Gordon, Kevin; Dooley, Joe

2010-03-01

To study postings of partial asphyxiation by adolescents on YouTube and to increase awareness of this dangerous activity as well as the value of YouTube as a research tool. Videos were searched on YouTube using many terms for recreational partial asphyxiation. Data were gathered on the participants and on the occurrence of hypoxic seizure. Sixty-five videos of the asphyxiation game were identified. Most (90%) participants were male. A variety of techniques were used. Hypoxic seizures were witnessed in 55% of videos, but occurred in 88% of videos that employed the "sleeper hold" technique. The videos were collectively viewed 173550 times on YouTube. YouTube has enabled millions of young people to watch videos of the "choking game" and other dangerous activities. Seeing videos may normalize the behavior among adolescents. Increased awareness of this activity may prevent some youths from participating and potentially harming themselves or others.

Choke or thrive? The relation between salivary cortisol and math performance depends on individual differences in working memory and math-anxiety.

PubMed

Mattarella-Micke, Andrew; Mateo, Jill; Kozak, Megan N; Foster, Katherine; Beilock, Sian L

2011-08-01

In the current study, we explored how a person's physiological arousal relates to their performance in a challenging math situation as a function of individual differences in working memory (WM) capacity and math-anxiety. Participants completed demanding math problems before and after which salivary cortisol, an index of arousal, was measured. The performance of lower WM individuals did not depend on cortisol concentration or math-anxiety. For higher WM individuals high in math-anxiety, the higher their concentration of salivary cortisol following the math task, the worse their performance. In contrast, for higher WM individuals lower in math-anxiety, the higher their salivary cortisol concentrations, the better their performance. For individuals who have the capacity to perform at a high-level (higher WMs), whether physiological arousal will lead an individual to choke or thrive depends on math-anxiety. 2011 APA, all rights reserved

Childhood and adolescent animal cruelty methods and their possible link to adult violent crimes.

PubMed

Hensley, Christopher; Tallichet, Suzanne E

2009-01-01

Few researchers have investigated the potentially predictive power of childhood and adolescent animal cruelty methods as they are associated with subsequent interpersonal violence in adulthood. Based on a sample of 261 inmates at medium- and maximum-security prisons in a southern state, the present study examines the relationship between several retrospectively reported animal cruelty methods (drowned, hit or kicked, shot, choked, burned, and had sex) and violent criminal acts committed against humans (assault, rape, and murder). More than half of the sample reported they had shot animals, and almost half had either kicked or hit them. About one in five said they had choked animals, and about one in seven said they had either drowned, burned, or had sex with them. Regression analyses revealed that drowning and having sex with an animal was predictive of later interpersonal violence as adults.

Investigation of starting transients in the thermally choked ram accelerator

NASA Technical Reports Server (NTRS)

Burnham, E. A.; Hinkey, J. B.; Bruckner, A. P.

1992-01-01

An experimental investigation of the starting transients of the thermally choked ram accelerator is presented in this paper. Construction of a highly instrumented tube section and instrumentation inserts provide high resolution experimental pressure, luminosity, and electromagnetic data of the starting transients. Data obtained prior to and following the entrance diaphragm show detailed development of shock systems in both combustible and inert mixtures. With an evacuated launch tube, starting the diffuser is possible at any Mach number above the Kantrowitz Mach number. The detrimental effects and possible solutions of higher launch tube pressures and excessive obturator leakage (blow-by) are discussed. Ignition of a combustible mixture is demonstrated with both perforated and solid obturators. The relative advantages and disadvantages of each are discussed. Data obtained from these starting experiments enhance the understanding of the ram accelerator, as well as assist in the validation of unsteady, chemically reacting CFD codes.

Neurological abnormalities in the `cri-du-chat' syndrome 1

PubMed Central

Colover, Jack; Lucas, Mary; Comley, J. A.; Roe, A. M.

1972-01-01

An unusual case of the cri-du-chat syndrome is described in a 6½ year old boy, who, as well as attacks of stridor and choking, showed disorders of spatial perception and cerebellar signs in the form of nystagmus, clumsiness of the hands, and ataxia. Pyramidal signs were also present. He was only mildly retarded mentally. Psychological testing showed that he had a severe deficit for number processing, and also constructional apraxia. Surprisingly, his vocabulary was quite good, as was his reading capacity. Chromosome analysis showed a very small deletion of the short arm of the group B chromosome. In infancy this diagnosis may be suspected because of the high-pitched cry and attacks of stridor and choking. In late childhood, when the signs may be only of a neurological disorder, its recognition may be difficult without confirmation from chromosome studies. The neurological features of this disease are reviewed. Images PMID:5084140

Who Chokes Under Pressure? The Big Five Personality Traits and Decision-Making under Pressure.

PubMed

Byrne, Kaileigh A; Silasi-Mansat, Crina D; Worthy, Darrell A

2015-02-01

The purpose of the present study was to examine whether the Big Five personality factors could predict who thrives or chokes under pressure during decision-making. The effects of the Big Five personality factors on decision-making ability and performance under social (Experiment 1) and combined social and time pressure (Experiment 2) were examined using the Big Five Personality Inventory and a dynamic decision-making task that required participants to learn an optimal strategy. In Experiment 1, a hierarchical multiple regression analysis showed an interaction between neuroticism and pressure condition. Neuroticism negatively predicted performance under social pressure, but did not affect decision-making under low pressure. Additionally, the negative effect of neuroticism under pressure was replicated using a combined social and time pressure manipulation in Experiment 2. These results support distraction theory whereby pressure taxes highly neurotic individuals' cognitive resources, leading to sub-optimal performance. Agreeableness also negatively predicted performance in both experiments.

Theoretical investigation of operation modes of MHD generators for energy-bypass engines

NASA Astrophysics Data System (ADS)

Tang, Jingfeng; Li, Nan; Yu, Daren

2014-12-01

A MHD generator with different arrangements of electromagnetic fields will lead the generator working in three modes. A quasi-one-dimensional approximation is used for the model of the MHD generator to analyze the inner mechanism of operation modes. For the MHD generator with a uniform constant magnetic field, a specific critical electric field E cr is required to decelerate a supersonic entrance flow into a subsonic exit flow. Otherwise, the generator works in a steady mode with a larger electric field than E cr in which a steady supersonic flow is provided at the exit, or the generator works in a choked mode with a smaller electric field than E cr in which the supersonic entrance flow is choked in the channel. The detailed flow field characteristics in different operation modes are discussed, demonstrating the relationship of operation modes with electromagnetic fields.

Computational Fluid Dynamic Modeling of Rocket Based Combined Cycle Engine Flowfields

NASA Technical Reports Server (NTRS)

Daines, Russell L.; Merkle, Charles L.

1994-01-01

Computational Fluid Dynamic techniques are used to study the flowfield of a fixed geometry Rocket Based Combined Cycle engine operating in rocket ejector mode. Heat addition resulting from the combustion of injected fuel causes the subsonic engine flow to choke and go supersonic in the slightly divergent combustor-mixer section. Reacting flow computations are undertaken to predict the characteristics of solutions where the heat addition is determined by the flowfield. Here, adaptive gridding is used to improve resolution in the shear layers. Results show that the sonic speed is reached in the unheated portions of the flow first, while the heated portions become supersonic later. Comparison with results from another code show reasonable agreement. The coupled solutions show that the character of the combustion-based thermal choking phenomenon can be controlled reasonably well such that there is opportunity to optimize the length and expansion ratio of the combustor-mixer.

Pulmonary decompression sickness at altitude: early symptoms and circulating gas emboli

NASA Technical Reports Server (NTRS)

Balldin, Ulf I.; Pilmanis, Andrew A.; Webb, James T.

2002-01-01

INTRODUCTION: Pulmonary altitude decompression sickness (DCS) is a rare condition. 'Chokes' which are characterized by the triad of substernal pain, cough, and dyspnea, are considered to be associated with severe accumulation of gas bubbles in the pulmonary capillaries and may rapidly develop into a life-threatening medical emergency. This study was aimed at characterizing early symptomatology and the appearance of venous gas emboli (VGE). METHODS: Symptoms of simulated-altitude DCS and VGE (with echo-imaging ultrasound) were analyzed in 468 subjects who participated in 22 high altitude hypobaric chamber research protocols from 1983 to 2001 at Brooks Air Force Base, TX. RESULTS: Of 2525 subject-exposures to simulated altitude, 1030 (41%) had symptoms of DCS. Only 29 of those included DCS-related pulmonary symptoms. Of these, only 3 subjects had all three pulmonary symptoms of chokes; 9 subjects had two of the pulmonary symptoms; and 17 subjects had only one. Of the 29 subject-exposures with pulmonary symptoms, 27 had VGE and 21 had severe VGE. The mean onset times of VGE and symptoms in the 29 subject-exposures were 42 +/- 30 min and 109 +/- 61 min, respectively. In 15 subjects, the symptoms disappeared during recompression to ground level followed by 2 h of oxygen breathing. In the remaining 14 cases, the symptoms disappeared with immediate hyperbaric oxygen treatment. CONCLUSIONS: Pulmonary altitude DCS or chokes is confirmed to be a rare condition. Our data showed that when diagnosed early, recompression to ground level pressure and/or hyperbaric oxygen treatment was 100% successful in resolving the symptoms.

Four cavity efficiency enhanced magnetically insulated line oscillator

DOEpatents

Lemke, Raymond W.; Clark, Miles C.; Calico, Steve E.

1998-04-21

A four cavity, efficient magnetically insulated line oscillator (C4-E MILO) having seven vanes and six cavities formed within a tube-like structure surrounding a cathode. The C4-E MILO has a primary slow wave structure which is comprised of four vanes and the four cavities located near a microwave exit end of the tube-like structure. The primary slow wave structure is the four cavity (C4) portion of the magnetically insulated line oscillator (MILO). An RF choke is provided which is comprised of three of the vanes and two of the cavities. The RF choke is located near a pulsed power source portion of the tube-like structure surrounding the cathode. The RF choke increases feedback in the primary slow wave structure, prevents microwaves generated in the primary slow wave structure from propagating towards the pulsed power source and modifies downstream electron current so as to enhance microwave power generation. A beam dump/extractor is located at the exit end of the oscillator tube for extracting microwave power from the oscillator, and in conjunction with an RF extractor vane, which comprises the fourth vane of the primary slow wave structure (nearest the exit) having a larger gap radius than the other vanes of the primary SWS, comprises an RF extractor. Uninsulated electron flow is returned downstream towards the exit along an anode/beam dump region located between the beam dump/extractor and the exit where the RF is radiated at said RF extractor vane located near the exit and the uninsulated electron flow is disposed at the beam dump/extractor.

Four cavity efficiency enhanced magnetically insulated line oscillator

DOEpatents

Lemke, R.W.; Clark, M.C.; Calico, S.E.

1998-04-21

A four cavity, efficient magnetically insulated line oscillator (C4-E MILO) having seven vanes and six cavities formed within a tube-like structure surrounding a cathode is disclosed. The C4-E MILO has a primary slow wave structure which is comprised of four vanes and the four cavities located near a microwave exit end of the tube-like structure. The primary slow wave structure is the four cavity portion of the magnetically insulated line oscillator (MILO). An RF choke is provided which is comprised of three of the vanes and two of the cavities. The RF choke is located near a pulsed power source portion of the tube-like structure surrounding the cathode. The RF choke increases feedback in the primary slow wave structure, prevents microwaves generated in the primary slow wave structure from propagating towards the pulsed power source and modifies downstream electron current so as to enhance microwave power generation. A beam dump/extractor is located at the exit end of the oscillator tube for extracting microwave power from the oscillator, and in conjunction with an RF extractor vane, which comprises the fourth vane of the primary slow wave structure (nearest the exit) having a larger gap radius than the other vanes of the primary SWS, comprises an RF extractor. Uninsulated electron flow is returned downstream towards the exit along an anode/beam dump region located between the beam dump/extractor and the exit where the RF is radiated at said RF extractor vane located near the exit and the uninsulated electron flow is disposed at the beam dump/extractor. 34 figs.

Mesoscale Circulation Variability from Five years of Quasi-continuous Glider Observations and Numerical Simulation at a Key Sub-basin 'Choke' Point.

NASA Astrophysics Data System (ADS)

Heslop, E. E.; Mourre, B.; Juza, M.; Troupin, C.; Escudier, R.; Torner, M.; Tintore, J.

2016-02-01

Quasi-continuous glider observations over 5 years have uniquely characterised a high frequency variability in the circulation through the Ibiza Channel, an important `choke' point in the Western Mediterranean Sea. This `choke' point governs the basin/sub-basin scale circulation and the north/south exchanges of different water masses. The resulting multi-scale variability impacts the regional shelf and open ocean ecosystems, including the spawning grounds of Atlantic bluefin tuna. Through the unique glider record we show the relevance of the weekly/mesoscale variability, which is of same order as the previously established seasonal and inter-annual variability. To understand the drivers of this variability we combine the glider data with numerical simulations (WMOP) and altimetry. Two key drivers are identified; extreme winter events, which cause the formation of a cold winter mode water (Winter Intermediate Water) in the shelf areas to the north of the Ibiza Channel, and mesoscale activity, which to the north produce channel `blocking' eddies and to the south intermittent and vigorous flows of fresher `Atlantic' waters through the Ibiza Channel. Results from the 2 km resolution WMOP are compared with the high-resolution (2 - 3 km.) glider data, giving insight into model validation across different scales, for both circulation and water masses. There is an emerging consensus that gliders can uniquely access critical time and length scales and in this study gliders complement existing satellite measurements and models, while opening up new capabilities for multidisciplinary, autonomous and high-resolution ocean observation.

76 FR 10038 - Determination That a Demonstration Needle Exchange Program Would be Effective in Reducing Drug...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-23

... Administration (SAMHSA), 1 Choke Cherry Road, Rockville, Maryland, attention John Campbell, 240-276-2891... tracks individuals in treatment over extended periods of time, most people who get into and remain in...

78 FR 37558 - Agency Information Collection Activities: Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-21

... Section 508 of the Rehabilitation Act to permit accessibility to people with disabilities. Every 2 years... Reports Clearance Officer, Room 2-1057, One Choke Cherry Road, Rockville, MD 20857 OR email her a copy at...

75 FR 53975 - Advisory Committee for Women's Services; Amendment of Meeting Notice

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-02

..., 1 Choke Cherry Road, Room 8-1016, Rockville, MD 20857, Telephone: 240.276.2331, FAX: 240.276.2251... Officer, Substance Abuse and Mental Health, Services Administration. [FR Doc. 2010-21917 Filed 9-1-10; 8...

Design and Analysis of an Electron Gun/Booster and Free Electron Laser Optical Theory

DTIC Science & Technology

2010-09-01

42 23. Simplified cathode assembly model . . . . . . . . . . . . . . . . . . . . 45 24. Rossendorf and BNL RF chokes...225 123. Cross-correlation maps . . . . . . . . . . . . . . . . . . . . . . . . . . . 227 124. BNL SDL optical field...amplitude . . . . . . . . . . . . . . . . . . . . . 230 125. BNL SDL Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230 xiii THIS

An approach for aerodynamic optimization of transonic fan blades

NASA Astrophysics Data System (ADS)

Khelghatibana, Maryam

Aerodynamic design optimization of transonic fan blades is a highly challenging problem due to the complexity of flow field inside the fan, the conflicting design requirements and the high-dimensional design space. In order to address all these challenges, an aerodynamic design optimization method is developed in this study. This method automates the design process by integrating a geometrical parameterization method, a CFD solver and numerical optimization methods that can be applied to both single and multi-point optimization design problems. A multi-level blade parameterization is employed to modify the blade geometry. Numerical analyses are performed by solving 3D RANS equations combined with SST turbulence model. Genetic algorithms and hybrid optimization methods are applied to solve the optimization problem. In order to verify the effectiveness and feasibility of the optimization method, a singlepoint optimization problem aiming to maximize design efficiency is formulated and applied to redesign a test case. However, transonic fan blade design is inherently a multi-faceted problem that deals with several objectives such as efficiency, stall margin, and choke margin. The proposed multi-point optimization method in the current study is formulated as a bi-objective problem to maximize design and near-stall efficiencies while maintaining the required design pressure ratio. Enhancing these objectives significantly deteriorate the choke margin, specifically at high rotational speeds. Therefore, another constraint is embedded in the optimization problem in order to prevent the reduction of choke margin at high speeds. Since capturing stall inception is numerically very expensive, stall margin has not been considered as an objective in the problem statement. However, improving near-stall efficiency results in a better performance at stall condition, which could enhance the stall margin. An investigation is therefore performed on the Pareto-optimal solutions to demonstrate the relation between near-stall efficiency and stall margin. The proposed method is applied to redesign NASA rotor 67 for single and multiple operating conditions. The single-point design optimization showed +0.28 points improvement of isentropic efficiency at design point, while the design pressure ratio and mass flow are, respectively, within 0.12% and 0.11% of the reference blade. Two cases of multi-point optimization are performed: First, the proposed multi-point optimization problem is relaxed by removing the choke margin constraint in order to demonstrate the relation between near-stall efficiency and stall margin. An investigation on the Pareto-optimal solutions of this optimization shows that the stall margin has been increased with improving near-stall efficiency. The second multi-point optimization case is performed with considering all the objectives and constraints. One selected optimized design on the Pareto front presents +0.41, +0.56 and +0.9 points improvement in near-peak efficiency, near-stall efficiency and stall margin, respectively. The design pressure ratio and mass flow are, respectively, within 0.3% and 0.26% of the reference blade. Moreover the optimized design maintains the required choking margin. Detailed aerodynamic analyses are performed to investigate the effect of shape optimization on shock occurrence, secondary flows, tip leakage and shock/tip-leakage interactions in both single and multi-point optimizations.

78 FR 76218 - Rural Call Completion

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-17

... calls to rural areas, and enforce restrictions against blocking, choking, reducing, or restricting calls... to alert the Commission of systemic problems receiving calls from a particular originating long... associated with completing calls to rural areas. These rules will also enhance our ability to enforce...

Clavicipitaceous anamorphic endophytes in Hordeum germplasm

Treesearch

A. Dan Wilson

2007-01-01

The incidence of clavicipitaceous anamorphic endophytes, non-choke inducing endosymbiotic fungi of the genus Neotyphodium that systemically infect grasses, in eighteen Hordeum species from the U.S. National Plant Germplasm System was examined using light and Scanning Electron Microscopy (SEM). Seventeen plant inventory accessions...

Origin of a Fungal Symbiont of Perennial Ryegrass by Interspecific Hybridization of a Mutualist with the Ryegrass Choke Pathogen, Epichloe Typhina

PubMed Central

Schardl, C. L.; Leuchtmann, A.; Tsai, H. F.; Collett, M. A.; Watt, D. M.; Scott, D. B.

1994-01-01

Seed-borne fungal symbionts (endophytes) provide many cool-season grass species with biological protection from biotic and abiotic stresses. The endophytes are asexual, whereas closely related sexual species of genus Epichloe (Clavicipitales) cause grass choke disease. Perennial ryegrass (Lolium perenne) is a host of two endophyte taxa, LpTG-1 (L. perenne endophyte taxonomic grouping one = Acremonium lolii) and LpTG-2, as well as the choke pathogen, Epichloe typhina (represented by isolate E8). Relationships among these fungi and other Epichloe species were investigated by analysis of gene sequences, DNA polymorphisms and allozymes. The results indicate that LpTG-2 is a heteroploid derived from an interspecific hybrid. The LpTG-2 isolates had two copies each of nine out of ten genes analyzed (the exception being the rRNA gene locus), and the profiles for seven of these were composites of those from E. typhina E8 and A. lolii isolate Lp5. Molecular phylogenetic analysis grouped the two β-tubulin genes of LpTG-2 into separate clades. One (tub2-1) was related to that of E. typhina E8, and the other (tub2-2) to that of A. lolii. The mitochondrial DNA profile of LpTG-2 was similar to that of A. lolii, but its rRNA gene sequence grouped it with E. typhina E8. A proposed model for the evolution of LpTG-2 involves infection of a L. perenne-A. lolii symbiotum by E. typhina, followed by hybridization of the two fungi. Such interspecific hybridization may be a common and important mechanism for genetic variation in Epichloe endophytes. PMID:8013907

GNSS Antenna Caused Near-Field Interference Effect in Precise Point Positioning Results

NASA Astrophysics Data System (ADS)

Dawidowicz, Karol; Baryła, Radosław

2017-06-01

Results of long-term static GNSS observation processing adjustment prove that the often assumed "averaging multipath effect due to extended observation periods" does not actually apply. It is instead visible a bias that falsifies the coordinate estimation. The comparisons between the height difference measured with a geometrical precise leveling and the height difference provided by GNSS clearly verify the impact of the near-field multipath effect. The aim of this paper is analysis the near-field interference effect with respect to the coordinate domain. We demonstrate that the way of antennas mounting during observation campaign (distance from nearest antennas) can cause visible changes in pseudo-kinematic precise point positioning results. GNSS measured height differences comparison revealed that bias of up to 3 mm can be noticed in Up component when some object (additional GNSS antenna) was placed in radiating near-field region of measuring antenna. Additionally, for both processing scenario (GPS and GPS/GLONASS) the scattering of results clearly increased when additional antenna crosses radiating near-field region of measuring antenna. It is especially true for big choke ring antennas. In short session (15, 30 min.) the standard deviation was about twice bigger in comparison to scenario without additional antenna. When we used typical surveying antennas (short near-field region radius) the effect is almost invisible. In this case it can be observed the standard deviation increase of about 20%. On the other hand we found that surveying antennas are generally characterized by lower accuracy than choke ring antennas. The standard deviation obtained on point with this type of antenna was bigger in all processing scenarios (in comparison to standard deviation obtained on point with choke ring antenna).

Preliminary Investigation of an Underwater Ramjet Powered by Compressed Air

NASA Technical Reports Server (NTRS)

Mottard, Elmo J.; Shoemaker, Charles J.

1961-01-01

Part I contains the results of a preliminary experimental investigation of a particular design of an underwater ramjet or hydroduct powered by compressed air. The hydroduct is a propulsion device in which the energy of an expanding gas imparts additional momentum to a stream of water through mixing. The hydroduct model had a fineness ratio of 5.9, a maximum diameter of 3.2 inches, and a ratio of inlet area to frontal area of 0.32. The model was towed at a depth of 1 inch at forward speeds between 20 and 60 feet per second for airflow rates from 0.1 to 0.3 pound per second. Longitudinal force and pressures at the inlet and in the mixing chamber were determined. The hydroduct produced a positive thrust-minus-drag force at every test speed. The force and pressure coefficients were functions primarily of the ratio of weight airflow to free-stream velocity. The maximum propulsive efficiency based on the net internal thrust and an isothermal expansion of the air was approximately 53 percent at a thrust coefficient of 0.10. The performance of the test model may have been influenced by choking of the exit flow. Part II is a theoretical development of an underwater ramjet using air as "fuel." The basic assumption of the theoretical analysis is that a mixture of water and air can be treated as a compressible gas. More information on the properties of air-water mixtures is required to confirm this assumption or to suggest another approach. A method is suggested from which a more complete theoretical development, with the effects of choking included, may be obtained. An exploratory computation, in which this suggested method was used, indicated that the effect of choked flow on the thrust coefficient was minor.

Three-step cylindrical seal for high-performance turbomachines

NASA Technical Reports Server (NTRS)

Hendricks, Robert C.

1987-01-01

A three-step cylindrical seal configuration representing the seal for a high performance turbopump (e.g., the space shuttle main engine fuel pump) was tested under static (nonrotating) conditions. The test data included critical mass flux and pressure profiles over a wide range of inlet temperatures and pressures for fluid nitrogen and fluid hydrogen with the seal in concentric and fully eccentric positions. The critical mass flux (leakage rate) was 70% that of an equivalent straight cylindrical seal with a correspondingly higher pressure drop based on the same flow areas of 0.3569 sq cm but 85% that of the straight seal based on the third-step flow area of 0.3044 sq cm. The mass flow rates for the three step cylindrical seal in the fully eccentric and concentric positions were essentially the same, and the trends in flow coefficient followed those of a simple axisymmetric inlet configuration. However, for inlet stagnation temperatures less than the thermodynamic critical temperature the pressure profiles exhibited a flat region throughout the third step of the seal, with the pressure magnitude dependent on the inlet stagnation temperature. Such profiles represent an extreme positive direct stiffness. These conditions engendered a crossover in the pressure profile upstream of the postulated choke that resulted in a local negative stiffness. Flat and crossover profiles resulting from choking within the seal are practically unknown to the seal designer. However, they are of critical importance to turbomachine stability and must be integrated into any dynamic analysis of a seal of this configuration. In addition, choking is highly dependent on geometry, inlet-to-backpressure ratio, and inlet temperature and can occur within the seal even though the backpressure is above the critical pressure.

505 Parachute Infantry Regiment (A Legacy of Lessons)

DTIC Science & Technology

1989-03-20

area being the critical choke point for a German counterattack of the invasion force. However, they had failed to predict the presence of Tiger tanks from...ineffective against the heavier Tiger tank and the paratroopers desperately improvised with captured German Eighty-eights and panzerfausts. Naval

Communicating Psychological Information in Writing.

ERIC Educational Resources Information Center

Iowa State Dept. of Public Instruction, Des Moines. Div. of Pupil Personnel Services.

The guide describes approaches and considerations involved in school psychologists' communication of information in reports. Following an initial tongue in cheek discussion ("On Skinning Cats, Choking Dogs, and Leaving Lovers") of principles of report writing (such as avoiding using the language of logic and not contaminating interpretations with…

16 CFR 1117.9 - Prohibited acts and sanctions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Prohibited acts and sanctions. 1117.9 Section 1117.9 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS REPORTING OF CHOKING INCIDENTS INVOLVING MARBLES, SMALL BALLS, LATEX BALLOONS AND OTHER SMALL...

Sugar Dehydration without Sulfuric Acid: No More Choking Fumes in the Classroom!

ERIC Educational Resources Information Center

Silverstein, Todd P.; Zhang, Yi

1998-01-01

Presents a demonstration that is a safe blend of two other vivid and memorable demonstrations. Combines two exothermic reactions involving granulated sugar to devise a reaction that produces a small amount of smoke and a growing column of black carbon. (DDR)

Bering Strait - Choke Point Control

DTIC Science & Technology

2016-05-13

for safeguarding the security of the Arctic region.” ii US defensive capabilities must expand beyond mere operating capability. To heed this...Dragon Eyes…”, p 4. ii Ibid, p 38. iii L. Brigham, et al, “Bering Strait Region Case Study,” Arctic Maritime Shipping Assessment, Arctic

Computational Analysis of the Combustion Processes in an Axisymmetric, RBCC Flowpath

NASA Technical Reports Server (NTRS)

Steffen, Christopher J., Jr.; Yungster, Shaye

2001-01-01

Computational fluid dynamic simulations have been used to study the combustion processes within an axisymmetric, RBCC flowpath. Two distinct operating modes have been analyzed to date, including the independent ramjet stream (IRS) cycle and the supersonic combustion ramjet (scramJet) cycle. The IRS cycle investigation examined the influence of fuel-air ratio, fuel distribution, and rocket chamber pressure upon the combustion physics and thermal choke characteristics. Results indicate that adjustment of the amount and radial distribution of fuel can control the thermal choke point. The secondary massflow rate was very sensitive to the fuel-air ratio and the rocket chamber pressure. The scramjet investigation examined the influence of fuel-air ratio and fuel injection schedule upon combustion performance estimates. An analysis of the mesh-dependence of these calculations was presented. Jet penetration data was extracted from the three-dimensional simulations and compared favorably with experimental correlations of similar flows. Results indicate that combustion efficiency was very sensitive to the fuel schedule.

The effects of emission control system malfunctions or maladjustments on exhaust emissions. Technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1976-10-01

The Environmental Protection Agency is currently undertaking programs that measure the exhaust emissions of in-use vehicles. One of these programs, the Emission Factors Program (EFP), has generated data indicating that a high percentage of in-use 1975 automobiles have exhaust emissions exceeding the Federal emission standards for 1975-1976 light-duty vehicles. Typical failing vehicles have very high CO emissions. High CO emissions may be indicative of improper adjustment of either the idle mixture or the choke. Since idle mixture and choke adjustments are easily accessible and adjusted on most cars, it seems probable that the maladjustment of these two items may bemore » responsible for some of the high emission levels measured in the EFP. In order to further investigate these possibilities, a test program was conducted by the EPA to quantify the effects of various engine maladjustments on exhaust emissions. This test program would help identify maladjustments resulting in the types of failures encountered in the EFP.« less

High-energy Neutrino Flares from X-Ray Bright and Dark Tidal Disruption Events

DOE Office of Scientific and Technical Information (OSTI.GOV)

Senno, Nicholas; Murase, Kohta; Mészáros, Peter

X-ray and γ-ray observations by the Swift satellite revealed that a fraction of tidal disruption events (TDEs) have relativistic jets. Jetted TDEs have been considered to be potential sources of very-high-energy cosmic-rays and neutrinos. In this work, using semi-analytical methods, we calculate neutrino spectra of X-ray bright TDEs with powerful jets and dark TDEs with possible choked jets, respectively. We estimate their neutrino fluxes and find that non-detection would give us an upper limit on the baryon loading of the jet luminosity contained in cosmic-rays ξ {sub cr} ≲ 20–50 for Sw J1644+57. We show that X-ray bright TDEs makemore » a sub-dominant (≲5%–10%) contribution to IceCube’s diffuse neutrino flux, and study possible contributions of X-ray dark TDEs given that particles are accelerated in choked jets or disk winds. We discuss future prospects for multi-messenger searches of the brightest TDEs.« less

Childhood animal cruelty methods and their link to adult interpersonal violence.

PubMed

Henderson, Brandy B; Hensley, Christopher; Tallichet, Suzanne E

2011-07-01

Recent research has begun to establish a relationship between childhood acts of animal cruelty and later violence against humans. However, few studies have focused on the influence of animal cruelty methods on later interpersonal violence. In a replication of a study by Hensley and Tallichet (2009) and based on a sample of 180 inmates at medium- and maximum-security prisons in a Southern state, the present study examines the relationship between several retrospectively identified animal cruelty methods (drowned, hit, shot, kicked, choked, burned, and sex) and interpersonal violence committed against humans. Four out of 5 inmates reported hitting animals. Over one third of the sample chose to shoot or kick animals, while 1 in 5 had sex with them. Less then one fifth of the sample drowned or choked animals, while less than one sixth of the inmates burned animals. Regression analyses revealed that the age at which offenders began committing animal cruelty and having sex with animals were predictive of adult interpersonal violence.

Pressure Amplification Off High Impedance Barriers in DDT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heatwole, Eric Mann; Broilo, Robert M.; Kistle, Trevin Joseph

The Deflagration-to-Detonation Transition (DDT) in one-dimensional porous explosive, where combustion in an explosive transitions to detonation, can be described by the following model. This simplified model proceeds in five steps, as follows: 1) Ignition of the explosive, surface burning. 2) Convective burning, with the flame front penetrating through the porous network of the explosive. This proceeds until the pressure grows high enough to result in choked flow in the pores restricting the convective burn. 3) The choked flow results in the formation of a high-density compact of explosive. This compact is driven into undisturbed material by the pressure of themore » burning explosive. See Figure1. 4) The compression of the undisturbed porous explosive by the compact leads to the ignition of a compressive burn. This builds in pressure until a supported shock forms. 5) The shock builds in pressure until detonation occurs. See Figure 2 for an overview streak of the proceeding steps.« less

Foreign body aspiration in children: A study of children who lived or died following aspiration.

PubMed

Mohammad, Maha; Saleem, Mohammad; Mahseeri, Mohamad; Alabdallat, Imad; Alomari, Ali; Za'atreh, Ala'; Qudaisat, Ibraheem; Shudifat, Abdulrahman; Nasri Alzoubi, Mohammad

2017-07-01

Foreign body aspiration (FBA) is a preventable cause of mortality and morbidity in children. We conducted a chart review of children who presented to a university hospital due to FBA in the period 1999-2014. Children were either managed with bronchoscopy for removal of the foreign body or died due to FBA. A total of 103 children were seen due to FBA including 27 deaths. The majority of children were boys and were less than 3 years old. Most aspirated foreign bodies were food-related, mainly peanuts. The majority of children presented with acute choking incidents, a smaller number presented with recurrent chest infections, and few children's choking incidents were unwitnessed. X-ray had a high rate of false negatives and bronchoscopy was the gold standard technique for assessment and management. Aspiration of foreign bodies is a preventable, life-threatening condition that calls for increased parent education and awareness. Copyright © 2017 Elsevier B.V. All rights reserved.

Possible options to slow down the advancement rate of Tarbela delta.

PubMed

Habib-Ur-Rehman; Rehman, Mirza Abdul; Naeem, Usman Ali; Hashmi, Hashim Nisar; Shakir, Abdul Sattar

2017-12-22

The pivot point of delta in Tarbela dam has reached at about 10.6 km from the dam face which may result in blocking of tunnels. Tarbela delta was modeled from 1979 to 2060 using hec-6 model. Initially, the model was calibrated for year 1999 and validated for years 2000, 2001, 2002, and 2006 by involving the data of sediment concentration, reservoir cross sections (73 range lines), elevation-area capacity curves, and inflows and outflows from the reservoir. Then, the model was used to generate future scenarios, i.e., run-1, run-2, and run-3 with pool levels; 428, 442, and 457 m, respectively, till 2060. Results of run-1 and run-2 showed advancement to choke the tunnels by 2010 and 2030, respectively. Finally, in run-3, the advancement was further delayed showing that tunnels 1 and 2 will be choked by year 2050 and pivot point will reach at 6.4 km from the dam face.

Investigation of the Rocket Induced Flow Field in a Rectangular Duct

NASA Technical Reports Server (NTRS)

Landrum, D. Brian; Thames, Mignon; Parkinson, Doug; Gautney, Serena; Hawk, Clark

1999-01-01

Several tests were performed on a one-sixth scale Rocket Based Combined Cycle (RBCC) engine model at the University of Alabama in Huntsville. The UAH RBCC facility consists of a rectangular duct with a vertical strut mounted in the center. The scaled strut consists of two supersonic rocket nozzles with an embedded vertical turbine between the rocket nozzles. The tests included mass flow, flow visualization and horizontal pressure traverses. The mass flow test indicated a c:hoked condition when the rocket chamber pressure is between 200 psi and 300 psi. The flow visualization tests narrowed the rocket chamber pressure range from, 250 psi to 300 psi. Also, from this t.est, an assumption of a minimum

Transformation of Epichloë typhina by electroporation of conidia

PubMed Central

2011-01-01

Background Choke, caused by the endophytic fungus Epichloë typhina, is an important disease affecting orchardgrass (Dactylis glomerata L.) seed production in the Willamette Valley. Little is known concerning the conditions necessary for successful infection of orchardgrass by E. typhina. Detection of E. typhina in plants early in the disease cycle can be difficult due to the sparse distribution of hyphae in the plant. Therefore, a sensitive method to detect fungal infection in plants would provide an invaluable tool for elucidating the conditions for establishment of infection in orchardgrass. Utilization of a marker gene, such as the green fluorescent protein (GFP), transformed into Epichloë will facilitate characterization of the initial stages of infection and establishment of the fungus in plants. Findings We have developed a rapid, efficient, and reproducible transformation method using electroporation of germinating Epichloë conidia isolated from infected plants. Conclusions The GFP labelled E. typhina provides a valuable molecular tool to researchers studying conditions and mechanisms involved in the establishment of choke disease in orchardgrass. PMID:21375770

Modeling of Compressible Flow with Friction and Heat Transfer Using the Generalized Fluid System Simulation Program (GFSSP)

NASA Technical Reports Server (NTRS)

Bandyopadhyay, Alak; Majumdar, Alok

2007-01-01

The present paper describes the verification and validation of a quasi one-dimensional pressure based finite volume algorithm, implemented in Generalized Fluid System Simulation Program (GFSSP), for predicting compressible flow with friction, heat transfer and area change. The numerical predictions were compared with two classical solutions of compressible flow, i.e. Fanno and Rayleigh flow. Fanno flow provides an analytical solution of compressible flow in a long slender pipe where incoming subsonic flow can be choked due to friction. On the other hand, Raleigh flow provides analytical solution of frictionless compressible flow with heat transfer where incoming subsonic flow can be choked at the outlet boundary with heat addition to the control volume. Nonuniform grid distribution improves the accuracy of numerical prediction. A benchmark numerical solution of compressible flow in a converging-diverging nozzle with friction and heat transfer has been developed to verify GFSSP's numerical predictions. The numerical predictions compare favorably in all cases.

State of the Art Control Measures for Aluminium Fade and SEN Clogging during Steelmaking Operations

NASA Astrophysics Data System (ADS)

Kamaraj, Ashok; Saravanakumar, R.; Rajaguru, M.

2018-02-01

Crack formation, fatigue failure of components and other process interruptions in liquid steel practices such as ladle nozzle clogging, SEN clogging, break outs are mainly due to residual deoxidation products such as alumina present in steels. The present paper deals with the issues in steel processing operations and provides state-of-the-art control measures for clean steel production. Investigations regarding the residual alumina content and its consequences at integrated steel plant shows that, Al-fade of maximum 0.02% is observed, which produces equivalent of 37 Kg of alumina in the liquid steel. Furthermore, slag carry over, re-oxidation, improper argon rinsing practice, aluminium consumption at secondary steelmaking practices also influences the alumina formation during steelmaking practices. The residual alumina not only affects the quality of steel, but also results in process interruptions such as ladle choking, SEN choking, subsequent break outs etc. various steelmaking practices influences clogging and aluminium fade are discussed and possible suggestions are given to improve the cleanliness of steel.

77 FR 73354 - Safety Standard for Hand-Held Infant Carriers

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-10

.... Edwards, Project Manager, Directorate for Engineering Sciences, U.S. Consumer Product Safety Commission, 5..., allergic reactions and near- choking episodes are the most common injuries reported in the remaining 58... modification of the ASTM standard to address the requirements for flammability, surface chemicals, cords...

16 CFR 1117.8 - Effect of reports on liability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Effect of reports on liability. 1117.8 Section 1117.8 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS REPORTING OF CHOKING INCIDENTS INVOLVING MARBLES, SMALL BALLS, LATEX BALLOONS AND OTHER SMALL...

Advanced Catalytic Enzyme System (ACES) - Dual Use Capabilities

DTIC Science & Technology

2003-07-01

Novozymes A/S (Bagsvaerd, Denmark) with activity against both cells and spores, and a bacteriophage enzyme (PlyG Lysin) that is specific for B. anthracis... Novozymes ), Lysozyme (commercial) Buffer: Ammonium carbonate Fire-Fighting Components: ColdFire®, Fire Choke® or an equivalent Class A foam The

Feeding and Swallowing Dysfunction in Genetic Syndromes

ERIC Educational Resources Information Center

Cooper-Brown, Linda; Copeland, Sara; Dailey, Scott; Downey, Debora; Petersen, Mario Cesar; Stimson, Cheryl; Van Dyke, Don C.

2008-01-01

Children with genetic syndromes frequently have feeding problems and swallowing dysfunction as a result of the complex interactions between anatomical, medical, physiological, and behavioral factors. Feeding problems associated with genetic disorders may also cause feeding to be unpleasant, negative, or even painful because of choking, coughing,…

Kudzu--Wonder Weed.

ERIC Educational Resources Information Center

Canipe, Stephen

Kudzu (Pueraria lobata) is a high climbing, exceedingly vigorous vine with twining stems (no tendrils or aerial holdfasts). The plant, introduced from the Orient and currently found in southeastern United States, has been known to choke valuable strands of trees, short electrical wires, and even creep up the sides of high rise buildings. Although…

IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR ACROLEIN (EXTERNAL REVIEW DRAFT)

EPA Science Inventory

Acrolein is a colorless to yellowish flammable liquid with a disagreeable, choking odor. The principal use of acrolein is as an intermediate in the synthesis of acrylic acid, which is used to make acrylates, and of DL-methionine, an essential amino acid used as an animal feed su...

75 FR 28264 - Privacy Act of 1974; Report of Systems of Record Notices

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-20

...: Research, Research Training, Research Scientist Development, Service, Education, Demonstration, Prevention... Substance Abuse Prevention, Section 515-8 (42 U.S.C. 290bb-21 et seq.). CMHS: Center for Mental Health... for Substance Abuse Prevention, Substance Abuse and Mental Health Services Administration, 1 Choke...

16 CFR 1501.3 - Exemptions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Exemptions. 1501.3 Section 1501.3 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS METHOD FOR IDENTIFYING TOYS AND OTHER ARTICLES INTENDED FOR USE BY CHILDREN UNDER 3 YEARS OF AGE WHICH PRESENT CHOKING, ASPIRATION, OR INGESTION HAZARDS...

16 CFR 1501.3 - Exemptions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Exemptions. 1501.3 Section 1501.3 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS METHOD FOR IDENTIFYING TOYS AND OTHER ARTICLES INTENDED FOR USE BY CHILDREN UNDER 3 YEARS OF AGE WHICH PRESENT CHOKING, ASPIRATION, OR INGESTION HAZARDS...

16 CFR 1501.3 - Exemptions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Exemptions. 1501.3 Section 1501.3 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS METHOD FOR IDENTIFYING TOYS AND OTHER ARTICLES INTENDED FOR USE BY CHILDREN UNDER 3 YEARS OF AGE WHICH PRESENT CHOKING, ASPIRATION, OR INGESTION HAZARDS...

Knocking out knotweed: research pins down a rogue invasive

Treesearch

Natasha Vizcarra; Shannon Claeson

2015-01-01

Bohemian knotweed spreads aggressively along rivers. This invasive weed chokes waterways, displaces native plants, erodes riverbanks, and keeps tree seedlings from growing. Communities in the Pacific Northwest spend millions of dollars to eradicate it on the assumption that it harms fish habitats.But knotweed is difficult to kill. It takes...

Behavioral Treatment of Aggression in the Mentally Retarded: A Review.

ERIC Educational Resources Information Center

Feldstein, Jerome H.

The paper reviews 34 behavioral treatment studies (1967-1983) examining reduction of aggressive behavior in mentally retarded people. Research reviewed was limited to treatment of physically aggressive responses such as hits, kicks, bites, chokes, scratches, and throwing objects by persons designated as mentally retarded. Among results reported…

40 CFR 610.21 - Device functional category and vehicle system effects.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 1 Device categories Characteristics adversely affected Fuel-Air System Carburetors and fuel injection systems All. Air-fuel ratio modifiers (e.g., air bleeds) All. Atomization devices (acoustic and mechanical) All. Vapor Injectors All. Choke controls 1, 2, and 4. Air filters 1, 2, and 4. Fuel-air...

40 CFR 610.21 - Device functional category and vehicle system effects.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 1 Device categories Characteristics adversely affected Fuel-Air System Carburetors and fuel injection systems All. Air-fuel ratio modifiers (e.g., air bleeds) All. Atomization devices (acoustic and mechanical) All. Vapor Injectors All. Choke controls 1, 2, and 4. Air filters 1, 2, and 4. Fuel-air...

40 CFR Appendix Vi to Part 86 - Vehicle and Engine Components

Code of Federal Regulations, 2010 CFR

2010-07-01

... exhaust valves. (2) Drive belts. (3) Manifold and cylinder head bolts. (4) Engine oil and filter. (5...) Carburetor-idle RPM, mixture ratio. (3) Choke mechanism. (4) Fuel system filter and fuel system lines and... filter breather cap. (4) Manifold inlet (carburetor spacer, etc.). V. External Exhaust Emission Control...

40 CFR Appendix Vi to Part 86 - Vehicle and Engine Components

Code of Federal Regulations, 2012 CFR

2012-07-01

... exhaust valves. (2) Drive belts. (3) Manifold and cylinder head bolts. (4) Engine oil and filter. (5...) Carburetor-idle RPM, mixture ratio. (3) Choke mechanism. (4) Fuel system filter and fuel system lines and... filter breather cap. (4) Manifold inlet (carburetor spacer, etc.). V. External Exhaust Emission Control...

40 CFR Appendix Vi to Part 86 - Vehicle and Engine Components

Code of Federal Regulations, 2014 CFR

2014-07-01

.... (2) Drive belts. (3) Manifold and cylinder head bolts. (4) Engine oil and filter. (5) Engine coolant...) Carburetor-idle RPM, mixture ratio. (3) Choke mechanism. (4) Fuel system filter and fuel system lines and... filter breather cap. (4) Manifold inlet (carburetor spacer, etc.). V. External Exhaust Emission Control...

40 CFR Appendix Vi to Part 86 - Vehicle and Engine Components

Code of Federal Regulations, 2013 CFR

2013-07-01

... exhaust valves. (2) Drive belts. (3) Manifold and cylinder head bolts. (4) Engine oil and filter. (5...) Carburetor-idle RPM, mixture ratio. (3) Choke mechanism. (4) Fuel system filter and fuel system lines and... filter breather cap. (4) Manifold inlet (carburetor spacer, etc.). V. External Exhaust Emission Control...

40 CFR Appendix Vi to Part 86 - Vehicle and Engine Components

Code of Federal Regulations, 2011 CFR

2011-07-01

... exhaust valves. (2) Drive belts. (3) Manifold and cylinder head bolts. (4) Engine oil and filter. (5...) Carburetor-idle RPM, mixture ratio. (3) Choke mechanism. (4) Fuel system filter and fuel system lines and... filter breather cap. (4) Manifold inlet (carburetor spacer, etc.). V. External Exhaust Emission Control...

Small size transformer provides high power regulation with low ripple and maximum control

NASA Technical Reports Server (NTRS)

Manoli, R.; Ulrich, B. R.

1971-01-01

Single, variable, transformer/choke device does work of several. Technique reduces drawer assembly physical size and design and manufacturing cost. Device provides power, voltage current and impedance regulation while maintaining maximum control of linearity and ensuring extremely low ripple. Nulling is controlled to very fine degree.

40 CFR 86.536-78 - Engine starting and restarting.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... initial 20 second idle period shall begin when the engine starts. (2) Choke operation. (i) Vehicles... transmission shall be placed in gear 15 seconds after the engine is started. If necessary, braking may be...

Control of clavicipitaceous anamorphic endophytes with fungicides, aerated steam and supercritical fluid CO2-seed extraction

Treesearch

A. Dan Wilson; Donald G. Lester; Brian K. Luckenbill

2008-01-01

The effects of soil drenches with systemic fungicides on viability of clavicipitaceous anamorphic endophytes, non-choke inducing endosymbiotic fungi of the genus Neotyphodium that systemically infect grasses, were tested in endophyte-infected seedlings of Hordeum brevisubulatum subsp. violaceum, Lolium perenne...

Preserving the Peach: Exploring Creativity in the Corporate Realm.

ERIC Educational Resources Information Center

Carrick, Moe

2000-01-01

Adventure consultation for businesses has the power and the tools to foster creative genius and grow corporate soul, to counteract the gravitational pull of corporate normalcy, referred to as the "corporate hairball." As the adventure consultant industry grows, it must beware of choking on its own hairballs. Five warning signs of…

16 CFR § 1501.3 - Exemptions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Exemptions. § 1501.3 Section § 1501.3 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS METHOD FOR IDENTIFYING TOYS AND OTHER ARTICLES INTENDED FOR USE BY CHILDREN UNDER 3 YEARS OF AGE WHICH PRESENT CHOKING, ASPIRATION, OR INGESTION HAZARDS...

16 CFR 1117.6 - Relation to section 15(b) of the CPSA.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Relation to section 15(b) of the CPSA. 1117.6 Section 1117.6 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS REPORTING OF CHOKING INCIDENTS INVOLVING MARBLES, SMALL BALLS, LATEX BALLOONS AND OTHER SMALL...

Safety Awareness: Empowering Students to be Technologically Literate

ERIC Educational Resources Information Center

Lazaros, Edward J.; Shackelford, Ray

2009-01-01

The Home Safety Council (2006) reports that home injuries make up one third of injuries in the United States. As the Home Safety Council (2006) reported, "the top five leading causes of unintentional home injury or death are falls, poisoning, fire/burn, choking/suffocation, and drowning." Because the home is separate from the school…

The Case of the Field Trip Disaster

ERIC Educational Resources Information Center

Collins, Loucrecia; Redcross, Joseph

2005-01-01

For decades, the instructional field trip has been viewed as a strategy to enhance students' learning experiences. Yet what happens when an award-winning teacher is accused of choking a student while on a field trip? Tempers flare among community members, parents contact the police, and the principal is assigned the daunting task of investigating…

First aid provision in nightclubs and other entertainment venues.

PubMed

Dean, R; Mulligan, J

This article discusses the role and responsibilities of the registered nurse in providing first aid in challenging environments, such as crowded nightclubs. Basic assistance for common emergencies, including substance misuse, wounds, choking and anaphylaxis, are discussed. This article emphasises the importance of risk assessment and reminds readers of the need to maintain personal safety.

One Last Chance

ERIC Educational Resources Information Center

Viadero, Debra

2004-01-01

Out amid the weed-choked factory lots and the bare yards of housing projects in Birmingham, Alabama, Steve Orel has become a kind of hero. The 50-year-old Orel runs the World of Opportunity School out of an old industrial building. Affectionately known as WOO, the school is a private, shoestring operation that offers students who have fallen…

Change in abundance of three phytophagous mite species (Acari: Eriophyidae, Tetranychidae) on quackgrass in the presence of choke disease

USDA-ARS?s Scientific Manuscript database

Phytophagous mites and endophytic fungi may interact when sharing a host plant, potentially influencing one another’s growth or population dynamics; however, interactions between them are poorly known and remain largely unexplored. In this study, quantitative associations between three species of ph...

30 CFR 250.447 - When must I pressure test the BOP system?

Code of Federal Regulations, 2010 CFR

2010-07-01

... OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations... pressure test your BOP system (this includes the choke manifold, kelly valves, inside BOP, and drill-string... performance warrant; and (c) Before drilling out each string of casing or a liner. The District Manager may...

76 FR 59710 - Center for Substance Abuse Prevention; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-27

... Abuse Prevention (CSAP) Drug Testing Advisory Board (DTAB) will meet on October 13, 2011 from 9 a.m. to... Guidelines for Federal Workplace Drug Testing Programs. Therefore, this meeting is closed to the public as..., Designated Federal Official, CSAP Drug Testing Advisory Board, 1 Choke Cherry Road, Room 2-1045, Rockville...

77 FR 45647 - Center for Substance Abuse Prevention; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-01

... Abuse Prevention (CSAP) Drug Testing Advisory Board (DTAB) will meet on August 27 and 28, 2012 from 10... Mandatory Guidelines for Federal Workplace Drug Testing Programs. Therefore, this meeting is closed to the... Cook, Ph.D., Designated Federal Official, CSAP Drug Testing Advisory Board, 1 Choke Cherry Road, Room 2...

Effects of two citrus-based commercial herbicides on giant reed, Arundo donax L. (Poaceae)

USDA-ARS?s Scientific Manuscript database

The giant reed, Arundo donax L. (Poaceae), is an invasive weed pest in the United States and other parts of the world, particularly in riparian habitats where it can hinder the flow of water and choke out indigenous vegetation. Conventional approaches to controlling A. donax have not been particular...

How a clogged canal affects ecological and human health in a tropical urban wetland ecosystem

EPA Science Inventory

The coastal city of San Juan, Puerto Rico is a tropical urban ecosystem woven among a series of interconnected bays, lagoons, drains, canals, and mangroves. As the city has expanded, infilling and urban development by the region’s poorest residents has choked an important c...

Meet Mai-Anh Ha | NREL

Science.gov Websites

find the best versions of the materials to guide experimentalists. "The world is complex," specifics," she says, "and then you can go from modeling into real-world applications." All to then choke me in my car," she says. Instead, she envisions a world filled with fuel cell cars

Helping Community-College Students Succeed: A Moral Imperative

ERIC Educational Resources Information Center

McClenney, Kay

2009-01-01

As is typical in a recession, many community colleges are experiencing a surge in enrollment, at precisely the same time that they must--like many enterprises, both public and private--contend with choking constraints on resources. The reality for community colleges is this: No matter how good this nation's colleges are today--and they do…

Clinical dysphagia risk predictors after prolonged orotracheal intubation

PubMed Central

de Medeiros, Gisele Chagas; Sassi, Fernanda Chiarion; Mangilli, Laura Davison; Zilberstein, Bruno; de Andrade, Claudia Regina Furquim

2014-01-01

OBJECTIVES: To elucidate independent risk factors for dysphagia after prolonged orotracheal intubation. METHODS: The participants were 148 consecutive patients who underwent clinical bedside swallowing assessments from September 2009 to September 2011. All patients had received prolonged orotracheal intubations and were admitted to one of several intensive care units of a large Brazilian school hospital. The correlations between the conducted water swallow test results and dysphagia risk levels were analyzed for statistical significance. RESULTS: Of the 148 patients included in the study, 91 were male and 57 were female (mean age, 53.64 years). The univariate analysis results indicated that specific variables, including extraoral loss, multiple swallows, cervical auscultation, vocal quality, cough, choking, and other signs, were possible significant high-risk indicators of dysphagia onset. The multivariate analysis results indicated that cervical auscultation and coughing were independent predictive variables for high dysphagia risk. CONCLUSIONS: Patients displaying extraoral loss, multiple swallows, cervical auscultation, vocal quality, cough, choking and other signs should benefit from early swallowing evaluations. Additionally, early post-extubation dysfunction recognition is paramount in reducing the morbidity rate in this high-risk population. PMID:24473554

Hospital level analysis to improve patient flow.

PubMed

Khanna, Sankalp; Boyle, Justin; Good, Norm; Bugden, Simon; Scott, Mark

2013-01-01

The complexity of hospital operations ensures that one-size-fits-all solutions seldom work. As hospitals turn to evidence based strategies to redesign flow, it is critical that they tailor the strategies to suit their individual service. This paper analyses the effect of hospital occupancy on inpatient and emergency department patient flow parameters at the Caboolture hospital in Queensland, Australia, and identifies critical levels, or choke points, that result in performance decline. The effect of weekdays and weekends on patient flow is also investigated. We compare these findings to a previous study that has analysed patient flow across Queensland hospitals grouped by size, and discover several differences in the interaction between rising occupancy and patient flow parameters including rates of patient flow, length of stay, and access block. We also identify significantly higher choke points for Caboolture hospital as compared to other similarly sized Queensland hospitals, which suggest that patient flow here can be redesigned to operate at higher levels of occupancy without degrading flow performance. The findings support arguments for hospitals to analyse patient flow at a service level to deliver optimum service improvement.

Depressurization and two-phase flow of water containing high levels of dissolved nitrogen gas

NASA Technical Reports Server (NTRS)

Simoneau, R. J.

1981-01-01

Depressurization of water containing various concentrations of dissolved nitrogen gas was studied. In a nonflow depressurization experiment, water with very high nitrogen content was depressurized at rates from 0.09 to 0.50 MPa per second and a metastable behavior which was a strong function of the depressurization rate was observed. Flow experiments were performed in an axisymmetric, converging diverging nozzle, a two dimensional, converging nozzle with glass sidewalls, and a sharp edge orifice. The converging diverging nozzle exhibited choked flow behavior even at nitrogen concentration levels as low as 4 percent of the saturation level. The flow rates were independent of concentration level. Flow in the two dimensional, converging, visual nozzle appeared to have a sufficient pressure drop at the throat to cause nitrogen to come out of solution, but choking occurred further downstream. The orifice flow motion pictures showed considerable oscillation downstream of the orifice and parallel to the flow. Nitrogen bubbles appeared in the flow at back pressures as high as 3.28 MPa, and the level at which bubbles were no longer visible was a function of nitrogen concentration.

Clinical dysphagia risk predictors after prolonged orotracheal intubation.

PubMed

Medeiros, Gisele Chagas de; Sassi, Fernanda Chiarion; Mangilli, Laura Davison; Zilberstein, Bruno; Andrade, Claudia Regina Furquim de

2014-01-01

To elucidate independent risk factors for dysphagia after prolonged orotracheal intubation. The participants were 148 consecutive patients who underwent clinical bedside swallowing assessments from September 2009 to September 2011. All patients had received prolonged orotracheal intubations and were admitted to one of several intensive care units of a large Brazilian school hospital. The correlations between the conducted water swallow test results and dysphagia risk levels were analyzed for statistical significance. Of the 148 patients included in the study, 91 were male and 57 were female (mean age, 53.64 years). The univariate analysis results indicated that specific variables, including extraoral loss, multiple swallows, cervical auscultation, vocal quality, cough, choking, and other signs, were possible significant high-risk indicators of dysphagia onset. The multivariate analysis results indicated that cervical auscultation and coughing were independent predictive variables for high dysphagia risk. Patients displaying extraoral loss, multiple swallows, cervical auscultation, vocal quality, cough, choking and other signs should benefit from early swallowing evaluations. Additionally, early post-extubation dysfunction recognition is paramount in reducing the morbidity rate in this high-risk population.

A novel fair active queue management algorithm based on traffic delay jitter

NASA Astrophysics Data System (ADS)

Wang, Xue-Shun; Yu, Shao-Hua; Dai, Jin-You; Luo, Ting

2009-11-01

In order to guarantee the quantity of data traffic delivered in the network, congestion control strategy is adopted. According to the study of many active queue management (AQM) algorithms, this paper proposes a novel active queue management algorithm named JFED. JFED can stabilize queue length at a desirable level by adjusting output traffic rate and adopting a reasonable calculation of packet drop probability based on buffer queue length and traffic jitter; and it support burst packet traffic through the packet delay jitter, so that it can traffic flow medium data. JFED impose effective punishment upon non-responsible flow with a full stateless method. To verify the performance of JFED, it is implemented in NS2 and is compared with RED and CHOKe with respect to different performance metrics. Simulation results show that the proposed JFED algorithm outperforms RED and CHOKe in stabilizing instantaneous queue length and in fairness. It is also shown that JFED enables the link capacity to be fully utilized by stabilizing the queue length at a desirable level, while not incurring excessive packet loss ratio.

Experimental investigation of heat transfer and flow pattern from heated horizontal rectangular fin array under natural convection

NASA Astrophysics Data System (ADS)

Taji, S. G.; Parishwad, G. V.; Sane, N. K.

2014-07-01

This paper presents results of the experimental study conducted on heated horizontal rectangular fin array under natural convection. The temperature mapping and the prediction of the flow patterns over the fin array with variable fin spacing is carried out. Dimensionless fin spacing to height (S/H) ratio is varied from 0.05 to 0.3 and length to height ratio (L/H) = 5 is kept constant. The heater input to the fin array assembly is varied from 25 to 100 W. The single chimney flow pattern is observed from 8 to 12 mm fin spacing. The end flow is choked below 6 mm fin spacing. The single chimney flow pattern changes to sliding or end flow choking at 6 mm fin spacing. The average heat transfer coefficient (ha) is very small (2.52-5.78 W/m2 K) at 100 W for S = 5-12 mm. The ha is very small (1.12-1.8 W/m2 K) at 100 W for 2-4 mm fin spacing due to choked fin array end condition. The end flow is not sufficient to reach up to central portion of fin array and in the middle portion there is an unsteady down and up flow pattern resulting in sliding chimney. The central bottom portion of fin array channel does not contribute much in heat dissipation for S = 2-4 mm. The ha has significantly improved at higher spacing as compared to lower spacing region. The single chimney flow pattern is preferred from heat transfer point of view. The optimum spacing is confirmed in the range of 8-10 mm. The average heat transfer results are compared with previous literature and showed similar trend and satisfactory agreement. An empirical equation has been proposed to correlate the average Nusselt number as a function of Grashof number and fin spacing to height ratio. The average error for this equation is -0.32 %.

Does poor oral health status increase the risk of falls?: The JAGES Project Longitudinal Study

PubMed Central

Mochida, Yuki; Fuchida, Shinya; Aida, Jun; Kondo, Katsunori

2018-01-01

We sought to examine if self-reported oral health conditions regarding difficulty eating tough foods, dry mouth, choking, number of teeth and denture use are associated with incident falls. Our study was based on panel data from the Japan Gerontological Evaluation Study conducted in 2010 and 2013 using self-administered questionnaires. Data from 19,995 male and 20,858 female community-dwelling older people aged ≥65 years without a history of falls within the previous year in 2010 were analyzed. Multilevel logistic regression models were used to determine the association between poor oral health in 2010 and multiple incident falls in 2013 after adjusting for possible confounders and considering differences in municipalities. The percentage of males and females who reported falls in 2013 were 2.4% and 2.1%, respectively. After adjusting for age, educational attainment, equivalized income, depression, self-rated health, instrumental activities of daily living, body mass index, present illness related to falls, social participation, walking in min/day, alcohol drinking status, and municipality population density, dry mouth in males (odds ratio [OR] = 1.41; 95% confidence interval [CI]: 1.12–1.77) and choking in females (OR = 1.64; 95% CI: 1.27–2.11) were significantly associated with incident falls. Difficulty eating tough foods in both sexes and choking in males were marginally associated with incident falls (p<0.1). Females having 10–19 teeth without dentures (OR = 1.63; 95% CI: 1.14–2.31), ≤9 teeth with dentures (OR = 1.36; 95% CI: 1.03–1.80), and ≤9 without dentures (OR = 1.46; 95% CI: 1.02–2.08) were significantly associated with incident falls compared with those having ≥20 teeth, respectively. These findings suggest that poor oral function, having fewer teeth, and not using dentures are predictors of incident falls. Further studies are needed to determine whether improving oral health can reduce the risk of falls. PMID:29389975

78 FR 69135 - Petitions for Modification of Application of Existing Mandatory Safety Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-18

..., because there is a chance that the water can become polluted from some external event such as a fire or...) The nature of any emergency itself could cause an external water supply to be polluted, choked, or... Affected: 30 CFR 75.1101-1(b) (Deluge-type water spray systems). Modification Request: The petitioner...

30 CFR 250.1610 - Blowout preventer systems and system components.

Code of Federal Regulations, 2011 CFR

2011-07-01

... pressure at least as great as the rated working pressure of the ram-type BOP's or as otherwise approved by..., and including, the choke manifold with a pressure rating at least as great as the rated working...-string operations, the BOP stack shall be equipped with conventional and/or variable-bore pipe rams to...

21 CFR 868.5115 - Device to relieve acute upper airway obstruction.

Code of Federal Regulations, 2014 CFR

2014-04-01

... the event of choking on a foreign body, can be applied to the abdomen and pushed upward to generate... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Device to relieve acute upper airway obstruction. 868.5115 Section 868.5115 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

21 CFR 868.5115 - Device to relieve acute upper airway obstruction.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Device to relieve acute upper airway obstruction. 868.5115 Section 868.5115 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... the event of choking on a foreign body, can be applied to the abdomen and pushed upward to generate...

Career and Technical Education Works for Rural Communities

ERIC Educational Resources Information Center

Warnock, Tania

2004-01-01

In Oklahoma, the state's CareerTech system is helping to provide resources and expertise to preserve the quality of life in rural communities. Just as many metropolitan areas feel the choke of urban sprawl, rural Oklahoma has, to a great extent, become the carbon copy of small towns across this country that are losing jobs, people and wealth.…

Status of NASA full-scale engine aeroelasticity research

NASA Technical Reports Server (NTRS)

Lubomski, J. F.

1980-01-01

Data relevant to several types of aeroelastic instabilities were obtained using several types of turbojet and turbofan engines. In particular, data relative to separated flow (stall) flutter, choke flutter, and system mode instabilities are presented. The unique characteristics of these instabilities are discussed, and a number of correlations are presented that help identify the nature of the phenomena.

Attending to the Execution of a Complex Sensorimotor Skill: Expertise Differences, Choking, and Slumps

ERIC Educational Resources Information Center

Gray, Rob

2004-01-01

A simulated baseball batting task was used to compare the relative effects of attending to extraneous information (tone frequency) and attending to skill execution (direction of bat movement) on performance and swing kinematics and to evaluate how these effects differ as a function of expertise. The extraneous dual task degraded batting…

30 CFR 250.1611 - Blowout preventer systems tests, actuations, inspections, and maintenance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conducting high-pressure tests, all BOP systems shall be tested to a pressure of 200 to 300 psi. (b) Ram-type BOP's and the choke manifold shall be pressure tested with water to rated working pressure or as otherwise approved by the District Manager. Annular type BOP's shall be pressure tested with water to 70...

30 CFR 250.448 - What are the BOP pressure tests requirements?

Code of Federal Regulations, 2010 CFR

2010-07-01

... you pressure test the BOP system, you must conduct a low-pressure and a high-pressure test for each BOP component. You must conduct the low-pressure test before the high-pressure test. Each individual... zero and reinitiate the test. (b) High-pressure test for ram-type BOPs, the choke manifold, and other...

30 CFR 250.1625 - Blowout preventer system testing, records, and drills.

Code of Federal Regulations, 2010 CFR

2010-07-01

... § 250.1625 Blowout preventer system testing, records, and drills. (a) Prior to conducting high-pressure tests, all BOP systems shall be tested to a pressure of 200 to 300 psi. (b) Ram-type BOP's and the choke manifold shall be pressure tested with water to a rated working pressure or as otherwise approved by the...

27 CFR 53.61 - Imposition and rates of tax.

Code of Federal Regulations, 2013 CFR

2013-04-01

... choke, a flash hider, a muzzle brake, a magazine, a set of sling swivels, and/or an attachable ramrod for muzzle loading firearms when provided by the manufacturer or importer for use with the firearm in... flash hiders/muzzle brakes of a type not provided by the manufacturer or importer of the firearm in the...

27 CFR 53.61 - Imposition and rates of tax.

Code of Federal Regulations, 2011 CFR

2011-04-01

... choke, a flash hider, a muzzle brake, a magazine, a set of sling swivels, and/or an attachable ramrod for muzzle loading firearms when provided by the manufacturer or importer for use with the firearm in... flash hiders/muzzle brakes of a type not provided by the manufacturer or importer of the firearm in the...

27 CFR 53.61 - Imposition and rates of tax.

Code of Federal Regulations, 2014 CFR

2014-04-01

... choke, a flash hider, a muzzle brake, a magazine, a set of sling swivels, and/or an attachable ramrod for muzzle loading firearms when provided by the manufacturer or importer for use with the firearm in... flash hiders/muzzle brakes of a type not provided by the manufacturer or importer of the firearm in the...

Is Self-Worth Protection Best Regarded as Intentional Self-Handicapping Behaviour or an Outcome of Choking under Pressure?

ERIC Educational Resources Information Center

Thompson, Ted; Dinnel, Dale L.

2007-01-01

Self-worth protective students characteristically perform poorly when they anticipate that poor performance is likely to reveal low ability, yet perform well in situations that involve little threat to self-worth. The present study sought a further understanding of this variable pattern of achievement, assessing two possibilities: (1) that the…

Multicenter, randomized, double-blind study comparing 20 and 40 mg of pantoprazole for symptom relief in adolescents (12 to 16 years of age) with gastroesophageal reflux disease (GERD)

USDA-ARS?s Scientific Manuscript database

An age-appropriate questionnaire (GASP-Q) was used to assess the frequency and severity of the gastroesophageal reflux disease (GERD) symptoms: abdominal/belly pain, chest pain/heartburn, pain after eating, nausea, burping/belching, vomiting/regurgitation, choking when eating, and difficulty swallow...

Arterial Gas Embolism Induced Ageusia (Case Report)

DTIC Science & Technology

2011-07-01

Pulmonary barotraumas are also reported in tbe literature; one case report described delayed onset pul- monary barotrauma in a diver which resolved...be rapidly fatal; it includes shock, pulmonary "chokes", and neurolog ic sequelae resembling cere- brovascular accidents due to nitrogen bubbles...pressures and may cause pneumothoraces. Air may evolve into the mediastinum (mediastinal emphysema ) or the skin (subcutaneous emphysema ). Lastly

The Effect of Pressure on High- and Low-Working-Memory Students: An Elaboration of the Choking under Pressure Hypothesis

ERIC Educational Resources Information Center

Wang, Zuowei; Shah, Priti

2014-01-01

Sample: Fifty-three third and fourth graders from China participated in this study. Method: Participants' working memory (WM) was assessed by the Automated Operation Span task. Then, they solved mental addition problems of different types under low- and high-pressure conditions. Performance was analysed as a function of pressure condition, working…

Enhancement of cadmium ion sorption capacity of lignocellulosic bio-sorbent by sulfonation

Treesearch

Eun W. Shin; James S. Han; Roger M. Rowell; Soo-Hong Min; James O. Peterson

2003-01-01

Water contaminated by heavy metals remains a serious environmental and public health problem. Cadmium is a toxic heavy metal that not only causes choking, abdominal pain, anemia, renal dysfunction, and diarrhea, but also has been listed as a carcinogen by the EPA (Gaballah and Kibertus, 1998). Among current technologies used to reduce the amount of heavy metals in...

Automated Airdrop Information Retrieval System-Human Fact ors Database (AAIRS-HFD) (Users Manual)

DTIC Science & Technology

1994-09-01

creeps, or chokes) Pressure Change Disorders Loss of Sensorimotor Abilities Loss of Cognitive/Perceptual Abilities Treatment drug therapy ...physical therapy cognitive therapy biofeedback therapy 73 9. Psychological Factors Situational Awareness altitude awareness Visual/Spatial...on/off valve prebreather Floatation Devices life preserver Scuba Gear Ankle Braces Knee Braces/Pads 82 7. Cargo/Resupply Parachute Assembly

Continuum theory: presbyphagia to dysphagia? Functional assessment of swallowing in the elderly.

PubMed

de Lima Alvarenga, Eliézia Helena; Dall'Oglio, Giovana Piovesan; Murano, Emi Zuiki; Abrahão, Márcio

2018-02-01

To investigate whether disclosed symptoms (coughing, choking and throat clearing) can be used as early predictors of swallowing disorders in non-hospitalized elderly population. In addition, to determine the presence of early findings of swallowing disorders through fiber optic endoscopic evaluation of swallowing (FEES). One hundred subjects older than 60 years were recruited from local community social meetings for seniors, they fulfilled inclusion criteria, and were given an oral interview and underwent FEES, with findings classified as: (1) saliva stasis; (2) pharyngeal residue; (3) penetration; (4) aspiration; (5) laryngeal sensitivity. Twenty-one percent of subjects declared previous choking, 10% coughing, and 7% throat clearing, 39% had pharyngeal residue; 6% saliva stasis; 9% penetration; 2% aspiration; and 92% laryngeal sensitivity present. Thirty-three percent showed pharyngeal residue without saliva stasis, while only 6% showed positivity for both (p = 0.003). Our data suggest that health care professionals should be aware that among an apparently healthy population, some subjects may have swallowing disorders without clinical complaints and that a nasolaryngoscopy exam may not be enough to predict dysphagia. We suggest that FEES should be performed to look for surrogate of dysphagia such as pharyngeal residue, laryngeal penetration, and aspiration.

The "choking game": a new craze among Brazilian children and young people. Psychophysiological, behavioral and epidemiological characteristics of 'asphyxial games'.

PubMed

Guilheri, Juliana; Andronikof, Anne; Yazigi, Latife

2017-03-01

The 'choking game' is a risk-taking behavior that has spread quickly among children and young people, causing dependence, accidents and even death, including in Brazil. These activities are performed in order to experience fleeting euphoric sensations, attracting numerous participants through the thousands of videos posted on YouTube. The problem of 'asphyxial games' can be observed in the Brazilian digital media, although there is a lack of scientific studies. Through a systematic review of the literature and complementary material, this paper aims to address the 'asphyxial games', warning about the psychophysiological and behavioral effects of these practices, while also presenting international epidemiological data. Sharing this information in academic circles is extremely important given the need to acquire more knowledge on the topic, train professionals and propose preventive measures that raise awareness among children and young people of the potential danger of voluntary fainting. It is equally important to raise awareness among parents and teachers so they can identify the warning signs that children may be engaging in these practices. And finally, it is also necessary to request government support to control exposure to videos that encourage the behavior.

High-Power Rf Load

DOEpatents

Tantawi, Sami G.; Vlieks, Arnold E.

1998-09-01

A compact high-power RF load comprises a series of very low Q resonators, or chokes [16], in a circular waveguide [10]. The sequence of chokes absorb the RF power gradually in a short distance while keeping the bandwidth relatively wide. A polarizer [12] at the input end of the load is provided to convert incoming TE.sub.10 mode signals to circularly polarized TE.sub.11 mode signals. Because the load operates in the circularly polarized mode, the energy is uniformly and efficiently absorbed and the load is more compact than a rectangular load. Using these techniques, a load having a bandwidth of 500 MHz can be produced with an average power dissipation level of 1.5 kW at X-band, and a peak power dissipation of 100 MW. The load can be made from common lossy materials, such as stainless steel, and is less than 15 cm in length. These techniques can also produce loads for use as an alternative to ordinary waveguide loads in small and medium RF accelerators, in radar systems, and in other microwave applications. The design is easily scalable to other RF frequencies and adaptable to the use of other lossy materials.

Compliance of Parenting Magazines Advertisements with American Academy of Pediatrics Recommendations.

PubMed

Pitt, Michael B; Berger, Jennifer N; Sheehan, Karen M

2016-11-01

This study examined 3218 advertisements from the two parenting magazines with highest circulation in the United States. The authors compared each advertisement for a product for use by children, against all the published recommendations of the American Academy of Pediatrics (AAP) on topics such as toy safety, helmet use, age-defined choking hazards, infant sleep safety, and others. Any advertisement with images or products which went against a published AAP recommendation was deemed as non-adherence and was categorized according to the statement it contradicted. Nearly one in six (15.7%) of the advertisements contained example(s) of non-adherence to AAP recommendations, with twelve categories of offense represented. Categories ranked by overall share from most to least include: non-Food and Drug Administration (FDA) approved medical treatments, age-defined choking hazards, vitamins, cold medicine, formula, oral care, screen time, toy/playground safety, infant sleep, nutrition, water safety, and fall risk. Given that repeated exposure to messages in advertisements has been associated with changes in health decision-making, and parents often turn to parenting magazines for advice and ideas regarding their children, the publishers might consider screening the content in order to prevent confusing and potentially dangerous messages from being disseminated in the media.

Design, development, and test of a laser velocimeter for a small 8:1 pressure ratio centrifugal compressor

NASA Technical Reports Server (NTRS)

Dolan, F. X.; Runstadler, P. W., Jr.

1979-01-01

The instrument was designed as a diagnostic tool for the basic fluid dynamics of the inducer, impeller, and diffuser regions of this type compressor. The LV instrumentation was optimized to measure instantaneous velocities up to approximately 500 m/s, measured in absolute coordinates, within the rotating compressor impeller and in the two dimensional radial plane of the diffuser. Some measurements were made within the diffuser and the impeller inlet flows; however, attempts to make detailed measurements of the velocity field were not successful. Difficulties in maintaining high seed particle rates within the probe volume and the improper operation of the blade gating optics may explain the lack of success. Recommendations are made to further pursue these problems. At 100% speed the stage attained a total static pressure ratio of 7.5:1 at 75% total-static efficiency. Flow range from choke-to-surge was 6.8% of choking mass flow rate. Performance was lower than the design intent of 8:1 pressure ratio at 77% efficiency and 12% flow range. Detailed measurements of the stage components are presented which show the reasons for the stage performance deficiencies.

Microwave antenna array for prostrate hyperthermia

NASA Astrophysics Data System (ADS)

Trembly, B. Stuart; Hoopes, P. Jack; Moodie, Karen L.; Dvinsky, Arik S.

1999-05-01

A pair of microwave applicators was developed to produce controlled elevation of temperature in the prostate. One applicator was designed for placement in the urethra; it has a diameter of 6 mm and is flexible. This applicator incorporates a choked, resonant microwave dipole with an omnidirectional heating pattern and an air cooling system to control the temperature of the urothelium. The second applicator was designed for placement in the rectum; it has a diameter of 18 mm and is rigid. It incorporates an eccentric, choked, resonant microwave dipole that radiates toward the prostate with a front-to-back power ratio of about twenty. An air cooling system controls the temperature of the rectal mucosa. The applicators are driven at 915 MHz with a phase difference chosen to produce the maximum temperature in the central prostate. We heated the prostates of eight canine subjects with the transurethral and transrectal applicators. After one or two months of followup in four subjects, the prostates and surrounding tissues were evaluated histologically. We present experimental measurements of the power deposition patterns of the applicators and the 3D temperature distributions in vivo, and we correlate the thermal dose with histopathological observations.

Modern Piracy: The Impact on Maritime Security

DTIC Science & Technology

2008-01-01

attacked Source: International Chamber of Commerce , Commercial Crime Bureau. http://www.eurocrime.it/sitelPiracy%20and%20Terrorism.pdf Piracy, simply put...agency of the International Chamber of Commerce (ICC), provide regular statistical data and reports of acts ofpiracy and armed robbery against ShipS.14...3: Key Maritime Choke-points / Piracy Hot Spots Source: International Chamber of Commerce , Commercial Crime Bureau. http://www.eurocrime.it/site

The Seeley Lake larch: Living link to indian and frontier history

Treesearch

Stephen F. Arno

2010-01-01

Western Montana’s Big Blackfoot River was once the gateway to a magnificent forest and the conduit that fed an immense sawmill. Epic log drives once choked the waterway full of timber each spring. The Big Blackfoot drainage was known for its majestic, centuries-old ponderosa pine and western larch trees. Although stately old ponderosas were widely distributed across...

Respiratory failure due to tracheobronchomalacia.

PubMed Central

Collard, P.; Freitag, L.; Reynaert, M. S.; Rodenstein, D. O.; Francis, C.

1996-01-01

A case is described of tracheobronchomegaly progressing to extensive tracheomalacia, complicated by episodic choking, recurrent pulmonary infections, and irreversible hypercapnic respiratory failure. A Y-shaped tracheobronchial stent was placed endoscopically to splint the trachea open, with excellent clinical and physiological improvement. New stent designs may provide long term palliation in selected cases of diffuse tracheal collapse or stenosis, and offer an alternative to surgical repair. PMID:8711665

K-Band Si/SiGe HBT MMIC Amplifiers Using Lumped Passive Components with a Micromachined Structure

NASA Technical Reports Server (NTRS)

Lu, Liang-Hung; Rieh, Jae-Sung; Bhattacharya, Pallab; Katechi, Linda P. B.; Croke, E. T.; Ponchak, George E.; Alterovitz, Samuel A.

2000-01-01

Using Si/SiGe heterojunction bipolar transistors with a maximum oscillation frequency of 52 GHz and a novel structure for passive components, a two-stage K-band lumped-element amplifier has been designed and fabricated on high-resistivity Si substrates. The chip size including biasing and RF chokes is 0.92 x 0.67 sq mm.

Heat fluxes across the Antarctic Circumpolar Current

NASA Astrophysics Data System (ADS)

Ferrari, Ramiro; Provost, Christine; Hyang Park, Young; Sennéchael, Nathalie; Garric, Gilles; Bourdallé-Badie, Romain

2014-05-01

Determining the processes responsible for the Southern Ocean heat balance is fundamental to our understanding of the weather and climate systems. Therefore, in the last decades, various studies aimed at analyzing the major mechanisms of the oceanic poleward heat flux in this region. Previous works stipulated that the cross-stream heat flux due to the mesoscale transient eddies was responsible for the total meridional heat transport across the Antarctic Circumpolar Current (ACC). Several numerical modelling and current meters data studies have recently challenged this idea. These showed that the heat flux due to the mean flow in the southern part of the Antarctic Circumpolar Current could be larger than the eddy heat flux contribution by two orders of magnitude. Eddy heat flux and heat flux by the mean flow distributions of were examined in Drake Passage using in situ measurements collected during the DRAKE 2006-9 project (from January 2006 to March 2009), available observations from the historical DRAKE 79 experiment and high resolution model outputs (ORCA 12, MERCATOR). The Drake Passage estimations provided a limited view of heat transport in the Southern Ocean. The small spatial scales shown by the model derived heat flux by the mean flow indicate that circumpolar extrapolations from a single point observation are perilous. The importance of the heat flux due by the mean flow should be further investigated using other in situ observations and numerical model outputs. Similar situation has been observed, with important implication for heat flux due to the mean flow, in other topographically constricted regions with strong flow across prominent submarine ridges (choke points). We have estimated the heat flux due to the mean flow revisiting other ACC mooring sites where in situ time series are available, e.g. south of Australia (Tasmania) (Phillips and Rintoul, 2000), southeast of New Zealand (Campbell Plateau) (Bryden and Heath, 1985). Heat fluxes due to the mean flow at those choke points were compared to model outputs and provided new circumpolar estimates indicating that the choke points are a potential overwhelming contribution for the heat flux needed to balance heat lost to the atmosphere in the Southern Ocean.

“Hello, HELLO! Anyone there? - on the need to assess the tsunami risk to global submarine telecommunications infrastructure

NASA Astrophysics Data System (ADS)

Dominey-Howes, D.; Goff, J. R.

2009-12-01

National economies are increasingly dependent on the global telecommunications system - and in particular, its submarine cable infrastructure. Submarine cable traffic represents about 30% of global GDP so the cost of losing, or even simply slowing, communications traffic is high. Many natural hazards are capable of damaging and destroying this infrastructure but tsunamis are the most significant threat, particularly in waters >1000 m deep. Submarine cables and their shore-based infrastructure (the anchor points), are at risk from direct and indirect tsunami-related effects. During the 2004 Indian Ocean Tsunami in India and Indonesia, cables were broken (direct effect) as the tsunami eroded supporting sediments, and were further damaged by floating/submerged objects and intense nearshore currents. Shore-based infrastructure was also directly damaged in India, Indonesia, and the Maldives. The 1929 Grand Banks earthquake generated a submarine landslide and tsunami off Newfoundland which broke 12 submarine telegraph cables. In 2006, an earthquake in Taiwan generated submarine landslides and a tsunami. These landslides caused one of the largest disruptions of modern telecommunications history when nine cables in the Strait of Luzon were broken disabling vital connections between SE Asia and the rest of the world. Although electronic traffic in and out of Australia was slowed, it did not cease because >70% of our traffic is routed via cables that pass through Hawaii. This is extremely significant because Hawaii is an internationally recognised bottleneck or “choke point” in the global telecommunications network. The fact that Hawaii is a choke point is important because it is regularly affected by numerous large magnitude natural hazards. Any damage to the submarine telecommunications infrastructure routed through Hawaii could result in significant impacts on the electronic flow of data and voice traffic, negatively affecting dependent economies such as Australia. Other choke points exist globally, many in high hazards regions. We propose that proper risk assessments be undertaken at all bottlenecks in the global telecommunications system affected by natural hazards (such as tsunami). We use Hawaii as an example of the sort of research that should be undertaken.

76 FR 63906 - Henry Gordy International, Inc., Provisional Acceptance of a Settlement Agreement and Order

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-14

...'' (``Target Set''). Each Target Set consisted of the following: A toy gun; soft, pliable, plastic toy darts... report of a death involving a Target Set on or about May 1, 2006, after an 8-year-old boy choked on a dart and died on March 9, 2006. 8. In response to the death reported on or about May 1, 2006, Henry...

Near Field Pressure Fluctuations in the Exit Plane of a Choked Axisymmetric Nozzle

NASA Technical Reports Server (NTRS)

Ponton, Michael K.; Seiner, John M.; Brown, Martha C.

1997-01-01

Nearfield pressure data are presented for an unheated jet issuing from an underexpanded sonic nozzle for two exit lip thicknesses of 0.200 and 0.625 nozzle diameters. Fluctuating measurements were obtained on the nozzle exit surface as well as in the acoustic nearfield. Narrowband spectra are presented for numerous operating conditions expressed in terms of the fully expanded Mach number based on nozzle pressure ratio.

High Energy Propulsion System (HEPS) Analysis

DTIC Science & Technology

1992-07-01

electrical power turb turbine f final condition; fusion vel velocity fire firing of rocket motor z longitudinal vii "* "choked" condition at nozzle...fraction of synchrotron radiation absorbed in the chamber walls. (it depends on "plasma depth," involving system geometry, plasma electrical ...increases by dv. By conservation of momentum, mdv = -v, dm (13) Integrating Eq. (13) and raising both sides to powers of e gives the well known

27. VIEW NORTHWEST FROM DECKING ON SOUTHEAST CORNER OF PIVOT ...

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

27. VIEW NORTHWEST FROM DECKING ON SOUTHEAST CORNER OF PIVOT PIER, DRIVE SYSTEM FOR SWING-SPAN INCLUDES: (from left to right) WEDGE DRIVE GEAR BOX, SHAFTS TO WEDGE DRIVE DRIVE, WEDGE DRIVE CRANK SHAFTS, ELECTRIC MOTOR, INTERNATIONAL HARVESTER GASOLINE ENGINE, CONTROL RODS FOR STARTING AND CHOKING ENGINE, PIVOT (bottom center), AND TRACK ON CONCRETE PIER - Tipers Bridge, Spanning Great Wicomico River at State Route 200, Kilmarnock, Lancaster County, VA

Characteristics of aeroelastic instabilities in turbomachinery - NASA full scale engine test results

NASA Technical Reports Server (NTRS)

Lubomski, J. F.

1979-01-01

Several aeromechanical programs were conducted in the NASA/USAF Joint Engine System Research Programs. The scope of these programs, the instrumentation, data acquisition and reduction, and the test results are discussed. Data pertinent to four different instabilities were acquired; two types of stall flutter, choke flutter and a system mode instability. The data indicates that each instability has its own unique characteristics. These characteristics are described.

Replace the Carburetor Diaphragm. Pulsa-Jet Style with Automatic Choke. Fuel System. Student Manual 2. Small Engine Repair Series. First Edition.

ERIC Educational Resources Information Center

Hill, Pamela

This student manual, part of a small-engine repair series on servicing fuel systems, is designed for use by special needs students in Texas. The manual explains in pictures and short sentences, written on a low reading level, the job of replacing carburetor diaphragms. Along with the steps of this repair job, specific safety and caution…

Power Supply For 25-Watt Arc Lamp

NASA Technical Reports Server (NTRS)

Leighty, B. D.

1985-01-01

Dual-voltage circuitry both strikes and maintains arc. New power supply designed (and several units already in use) that replaces relay/choke combination with solid-state starter. New power supply consists of two main sections. First section (low voltage power supply section) is 84-volt directcurrent supply. Second section (high-voltage starter circuit) is CockroftWalton voltage multiplier. Used as light sources for schlieren, shadowgraph, and other flow-visualization techniques.

Ace in the Hole: Fischer-Tropsch Fuels and National Security

DTIC Science & Technology

2010-05-24

German might.”9 As the Allies’ strategic bombing campaign destroyed German refineries and choked imports from Rumanian refineries , Germany relied more...hydrocarbon structure.53 The 16 synthetic fuel contains no impurities, providing a superior aviation fuel with no sulfur emissions or particulates, and... emissions , Congress effectively killed CTL fuel development in the United States with an amendment to the Energy Independence and Security Act so that

Caspian Sea International Environmental Security Game. Held at Carlisle Barracks, Pennsylvania on 16-17 November 1998

DTIC Science & Technology

1999-07-01

Environmental Security . . . . . . . . . . . . . . . . . . . . 17 Robert E. Ebel Caspian Basin Oil and Gas: An Overview . . . . . . . . . . . 21 Brian R ...choke point near Baku, posing a threat to security of supply. 32 ENVIRONMENTAL BASELINE ANALYSIS OF THE CASPIAN SEA REGION BRIAN R . SHAW TERRY...up to 70% of the seasonal Caspian Sea level. Sources of water include runoff ( R ), precipitation (P), and groundwater flow (G); sink include

Predictors of radiolucent foreign body aspiration.

PubMed

Mortellaro, Vincent E; Iqbal, Corey; Fu, Roxanna; Curtis, Heather; Fike, Frankie B; St Peter, Shawn D

2013-09-01

Children frequently present for suspected foreign body aspiration, many have mild symptoms and/or negative radiographs raising the question of a radiolucent foreign body aspiration. Retrospective review of patients having bronchoscopy for suspected radiolucent foreign body aspiration from 2000 to 2010 collecting demographics, history, hospital presentation, radiographic, and operative details. Pearson's correlation was used between event history, presentation, radiographic details and bronchoscopically identified foreign body with P value <0.01. 138 patients, mean age 2.6 years, mean weight 15.6 kg, 68% male. Event symptoms: 81% witnessed events, 64% wheezing, 43% coughing, 39% choking, 6% stridor, and 0.7% lethargy. Hospital presentation: 70% persistent symptoms, wheezing 56%, coughing 15%, desaturations 11%, stridor 7%, choking 4%, and lethargy 1%. 92% of patients had a chest x-ray; air trapping found in 38%, and lung collapse in 21%. 2 patients received CT scans; 1 had lung collapse. Bronchoscopy identified foreign bodies in 93% of patients: food 68%, plastic 18%, non-descript 11%, rocks 3%. No correlations between event symptoms, hospital presentation, radiographs and foreign body presence. Event history, hospital presentation, and radiographs are insufficient in proving the absence of a radiolucent foreign body. Patients with suspected radiolucent foreign body aspiration should undergo diagnostic bronchoscopy prior to discharge. Copyright © 2013 Elsevier Inc. All rights reserved.

Estimating gas kick arrival to better manage surface flow

DOE Office of Scientific and Technical Information (OSTI.GOV)

Merryman, J.

1997-06-01

There are many quality, expertly designed programs for teaching rig crews prevention and control of well kicks. Much time and money has been spent training rig crews for procedures and methods to avoid kicks, and what to do if you have one, even though all accepted practices were followed. One false/bad result from this training is that individuals have come away from this training believing that once a gas kick is circulated through the choke, all problems are simple and manageable, i.e., the danger has passed. What you do with gas once it is downstream of the choke has notmore » been given enough emphasis in some training programs, including the one the author is involved in. This article, prepared from experiences on actual rig locations in Wyoming and Argentina, and developed for well control training in Parker Drilling Co.`s Training Center, Odessa, Texas, describes a method for estimating the time, in pump strokes and/or minutes, for a gas kick to reach surface. Reducing pump strokes (circulating flowrate) and knowing available time to gas kick arrival allows the crew to prepare surface handling equipment. Common misconceptions about gas handling and potential resulting problems are noted. An example calculation describes the calculation procedure.« less

Compliance of Parenting Magazines Advertisements with American Academy of Pediatrics Recommendations

PubMed Central

Pitt, Michael B.; Berger, Jennifer N.; Sheehan, Karen M.

2016-01-01

This study examined 3218 advertisements from the two parenting magazines with highest circulation in the United States. The authors compared each advertisement for a product for use by children, against all the published recommendations of the American Academy of Pediatrics (AAP) on topics such as toy safety, helmet use, age-defined choking hazards, infant sleep safety, and others. Any advertisement with images or products which went against a published AAP recommendation was deemed as non-adherence and was categorized according to the statement it contradicted. Nearly one in six (15.7%) of the advertisements contained example(s) of non-adherence to AAP recommendations, with twelve categories of offense represented. Categories ranked by overall share from most to least include: non-Food and Drug Administration (FDA) approved medical treatments, age-defined choking hazards, vitamins, cold medicine, formula, oral care, screen time, toy/playground safety, infant sleep, nutrition, water safety, and fall risk. Given that repeated exposure to messages in advertisements has been associated with changes in health decision-making, and parents often turn to parenting magazines for advice and ideas regarding their children, the publishers might consider screening the content in order to prevent confusing and potentially dangerous messages from being disseminated in the media. PMID:27809284

Inhaled foreign bodies in children: a global perspective on their epidemiological, clinical, and preventive aspects.

PubMed

Foltran, Francesca; Ballali, Simonetta; Rodriguez, Hugo; Sebastian van As, Arjan B; Passali, Desiderio; Gulati, Achal; Gregori, Dario

2013-04-01

While several articles describe clinical management of foreign bodies injuries in the upper air tract, little epidemiological evidence is available from injury databases. This article aims to understand the burden of airway FB injuries in high-, low-, and middle-income countries as emerging from scientific literature. One thousand six hundred ninety-nine published articles 1978-2008. A free text search on PubMed database ((foreign bodies) or (foreign body)) and ((aspiration) or (airways) or (tracheobronchial) or (nasal) or (inhalation) or (obstruction) or (choking) or (inhaled) or (aspirations) or (nose) or (throat) or (asphyxiation)) and ((children) or (child)). Information on reported injuries according to country, time period, children sex and age, FB type, site of obstruction, symptoms, signs, diagnostic and therapeutic procedures, delay at the diagnosis, complications, number of deaths. Serious complications occur both in high-income and low-middle income countries in a considerable proportion of cases (10% and 20%, respectively). Similarly, death is not infrequent (5-7% of cases). Few countries have good systematic data collection and there's a lack of sensibility in parents and clinicians in terms of acknowledge of the choking risk. On the contrary, international surveillance systems able to collect information in a standardized way need to be implemented. Copyright © 2012 Wiley Periodicals, Inc.

Adjustable steam producing flexible orifice independent of fluid pressure

NASA Technical Reports Server (NTRS)

Morrison, Andrew D. (Inventor)

1992-01-01

A self-adjusting choke for a fluids nozzle includes a membrane constructed of a single piece of flexible or elastic material. This flexible material is shaped to fit into the outlet of a nozzle. The body of the membrane has at least two flow channels, from one face to the other, which directs two streams of water to cross at the opening of the nozzle or at some point beyond. The elasticity and thickness of the membrane is selected to match the range of expected pressures and fluid velocities. The choke may have more than two flow channels, as long as they are aligned adjacent to one another and directed towards each other at the exit face. In a three orifice embodiment, one is directed upward, one is directed downward, and the one in the middle is directed forward. In this embodiment all three fluid streams intersect at some point past the nozzle opening. Under increased pressure the membrane will deform causing the orifices to realign in a more forward direction, causing the streams to intersect at a smaller angle. This reduces the force with which the separate streams impact each other, still allowing the separate streams to unify into a single stable spiralling stream in spite of the increased pressure.

The Challenge of Drug Trafficking to Democratic Governance and Human Security in West Africa

DTIC Science & Technology

2013-05-01

Washing ton, DC, as the Director of the Office of Environmental Policy; as Economic Officer in the Bu- reau of Econom ic and Business Affairs... Colombian cartels established links with Mexican syndicates after the United States significantly choked off the old Ca- ribbean drug...transportation corridor and forced the Colombians to start moving their drug loads across the southwest border of the United States.48 Mexican DTOs, including

Home safety measures and the risk of unintentional injury among young children: a multicentre case–control study

PubMed Central

LeBlanc, John C.; Pless, I. Barry; King, W. James; Bawden, Harry; Bernard-Bonnin, Anne-Claude; Klassen, Terry; Tenenbein, Milton

2006-01-01

Background Young children may sustain injuries when exposed to certain hazards in the home. To better understand the relation between several childproofing strategies and the risk of injuries to children in the home, we undertook a multicentre case–control study in which we compared hazards in the homes of children with and without injuries. Methods We conducted this case-control study using records from 5 pediatric hospital emergency departments for the 2-year period 1995–1996. The 351 case subjects were children aged 7 years and less who presented with injuries from falls, burns or scalds, ingestions or choking. The matched control subjects were children who presented during the same period with acute non-injury-related conditions. A home visitor, blinded to case-control status, assessed 19 injury hazards at the children's homes. Results Hazards found in the homes included baby walkers (21% of homes with infants), no functioning smoke alarm (17% of homes) and no fire extinguisher (51% of homes). Cases did not differ from controls in the mean proportion of home hazards. After controlling for siblings, maternal education and employment, we found that cases differed from controls for 5 hazards: the presence of a baby walker (odds ratio [OR] 9.0, 95% confidence interval [CI] 1.1–71.0), the presence of choking hazards within a child's reach (OR 2.0, 95% CI 1.0–3.7), no child-resistant lids in bathroom (OR 1.6, 95% CI 1.0–2.5), no smoke alarm (OR 3.2, 95% CI 1.4–7.7) and no functioning smoke alarm (OR 1.7, 95% CI 1.0–2.8). Interpretation Homes of children with injuries differed from those of children without injuries in the proportions of specific hazards for falls, choking, poisoning and burns, with a striking difference noted for the presence of a baby walker. In addition to counselling parents about specific hazards, clinicians should consider that the presence of some hazards may indicate an increased risk for home injuries beyond those directly related to the hazard found. Families with any home hazard may be candidates for interventions to childproof against other types of home hazards. PMID:16998079

The fate of Mediterranean lagoons under climate change

NASA Astrophysics Data System (ADS)

Umgiesser, Georg; Ferrarin, Christian; Cucco, Andrea; De Pascalis, Francesca; Ghezzo, Michol; Bellafiore, Debora; Bajo, Marco

2014-05-01

A numerical model (SHYFEM) has been applied to 10 Mediterranean lagoons and a comparison study between the lagoons has been carried out. The lagoons are the lagoons of Venice, Marano-Grado, Varano and Lesina in the Adriatic Sea, the Taranto basin in the Ionian Sea, the Cabras lagoon in Sardinia, and the lagoons of Ganzirri and Faro in Sicily, the Mar Menor in Spain and the Nador lagoon in Morocco. These lagoons give a representative picture of the lagoons situated around the Mediterranean basin. The lagoons range from a leaky type of lagoons to a choked type. The number of inlets ranges from just one in the Nador lagoon to 6 in the case of the Marano-Grado lagoons. Tidal range is from nano-tidal to micro-tidal. The depth ranges from an average depth of 1 m to up to 40 meters. The model is a finite element model, especially suited to shallow water basins with complicated geometric and morphologic variations. The model can compute the basic hydrodynamics, dispersion of tracers, temperature and salinity evolution, sediment transport and ecological parameters. Building on an earlier study that focused on the classification of Mediterranean lagoons based on hydrodynamics, exchange rates and renewal time, this study is concerned with the changes in physical parameters under climate change. Data from IPCC has been used to simulate the changes in renewal time, salinity and temperature of all lagoons, with respect to the control simulation. Whenever possible downscaled data for the Mediterranean basin have been used. Sea level rise scenarios are taken from the last IPCC report. The model has been applied in its 3D version and the chosen setup allows a comparison between results in the different lagoons. Results indicate that the differences of renewal time between all studied lagoons become smaller. This means that leaky lagoons become less leaky and choked lagoons less choked. What concerns temperature and salinity, changes occurring in the sea are amplified inside lagoons. All lagoons show an increase of temperature higher than the one found outside in the sea. Salinity changes are also enhanced. This study shows how numerical modeling can be a useful tool to study the hydrodynamic changes forecasted to happen in transitional water bodies like lagoons.

Analysis of prevertebral soft-tissue swelling and dysphagia in multilevel anterior cervical discectomy and fusion with recombinant human bone morphogenetic protein-2 in patients at risk for pseudarthrosis.

PubMed

Stachniak, Joseph B; Diebner, Jeffrey D; Brunk, Estee S; Speed, Shelley M

2011-02-01

The goal of this study was to demonstrate the incidence of fusion and soft-tissue swelling in multilevel anterior cervical discectomies and fusions (ACDFs) using polyetheretherketone (PEEK) spacers with recombinant human bone morphogenetic protein-2 (rhBMP-2) impregnated in a Type I collagen sponge and titanium plates. A single surgeon performed 30 multilevel ACDFs using PEEK spacers with an rhBMP-2 impregnated collagen sponge (0.4 ml, or the equivalent of 0.6 mg rhBMP-2). Soft-tissue swelling was assessed using cervical spine radiographs on postoperative Day 1 and at 2, 6, and 10 weeks and 6 months after surgery. Incidence of dysphagia was assessed with the Cervical Spine Research Society Swallowing-Quality of Life tool. Clinical success was evaluated with the Neck Disability Index, neck pain scores, and arm pain scores. Final fusion was assessed with CT by an independent neuroradiologist. Patients were followed for 6 months unless they had an incomplete fusion; those patients were reassessed at 9 months. Twenty-four patients underwent 2-level ACDFs and 6 underwent 3-level ACDFs were performed on patients with the following risk factors for pseudarthrosis: smoking (33%), diabetes (13%), and obesity (body mass index ≥ 30 [43%]). Seventeen percent of the patients had multiple risk factors. Soft-tissue swelling peaked at 2 weeks regardless of level of surgery or number of levels treated surgically and decreased to near preoperative levels by 6 months. At 2 weeks, Swallowing-Quality of Life evaluation showed 19% of patients frequently choking on food, 4.8% frequently choking when drinking, and 47.6% with frequent food sticking in the throat. Scores continued to improve, and at 6 months, 0% had frequent choking on food, 6.7% had frequent difficulty drinking, and 6.7% had frequent food sticking in the throat. The Neck Disability Index, neck pain, and arm pain scores all improved progressively over 6 months. Incidence of fusion was 95% at 6 months and 100% at 9 months. There were no rehospitalizations or reoperations for soft-tissue swelling or dysphagia. Multilevel ACDF procedures using PEEK grafts and rhBMP-2 can be performed safely in patients with multiple risk factors for pseudarthrosis with excellent fusion outcomes.

Installation Effects on Heat Transfer Measurements for a Turbine Vane

DTIC Science & Technology

2003-03-01

turbine vanes and blades in order to acquire high accuracy, high frequency response data. Typically the installation procedure has involved either mounting...length scale such as blade chord) again matches the engine value. Also before the start of the run a choke valve downstream of the turbine is set to...of Engineering for Gas Turbines and Power (January 1984), Volume 106. p 229 - 240. Gibbings, J.C. “On boundary Layer Transition Wires.” Aeronautical

Effects of Fuel Spray Modeling on Combustion Instability Predictions in a Single-Element Lean Direct Injection (LDI) Gas Turbine Combustor

DTIC Science & Technology

2014-09-01

evaporation in the vicinity of the injector . Recently, Kim and Menon 9 applied the same approach to study the characteristics of longitudinal...phenomena that govern the occurrence of combustion instabilities. The experiments involve a single injector element in a longitudinal mode combustor with...well characterized inflow conditions and a choked nozzle exit condition. Varying parameters such as the length of the air plenum, the combustor length

Salinity, Temperature, and Optical Characterization of a Tidally Choked Estuary Connected to Two Contrasting Intra-Coastal Waterways

DTIC Science & Technology

2013-06-01

phytoplankton production, and hence chlorophyll a concentration. As a result, light absorption in coastal waters is dominated by CDOM, while light ...water influence in the ocean and to track river plumes in open water (Chen 1999). In one particular case, the addition of chlorophyll a fluorescence...matter (CDOM) (Chen 1999) that consists of the humic and fluvic acids (yellow substance) of decaying plant matter (Nieke et al. 1997). Like chlorophyll

Aerothermodynamic flow phenomena of the airframe-integrated supersonic combustion ramjet

NASA Technical Reports Server (NTRS)

Walton, James T.

1992-01-01

The unique component flow phenomena is discussed of the airframe-integrated supersonic combustion ramjet (scramjet) in a format geared towards new players in the arena of hypersonic propulsion. After giving an overview of the scramjet aerothermodynamic cycle, the characteristics are then covered individually of the vehicle forebody, inlet, combustor, and vehicle afterbody/nozzle. Attention is given to phenomena such as inlet speeding, inlet starting, inlet spillage, fuel injection, thermal choking, and combustor-inlet interaction.

Dysphagia and dentistry.

PubMed

Curl, Charlotte; Boyle, Carole

2014-06-01

Dysphagia is defined as a 'difficulty in swallowing' and is commonly found in the general population, particularly in the elderly. This article gives an overview of the more frequently encountered swallowing disorders and provides advice on how to manage the dysphagic patient in the dental surgery. Clinical Relevance: By identifying patients with dysphagia and being aware of the potential problems that the clinician may experience when treating them, the risk of aspiration, choking and healthcare-acquired upper respiratory tract infections may be reduced.

Does concomitant anterior fundoplication promote dysphagia after laparoscopic Heller myotomy?

PubMed

Tapper, Donovan; Morton, Connor; Kraemer, Emily; Villadolid, Desiree; Ross, Sharona B; Cowgill, Sarah M; Rosemurgy, Alexander S

2008-07-01

Concerns for gastroesophageal reflux after laparoscopic Heller myotomy for achalasia justify considerations of concomitant anterior fundoplication. This study was undertaken to determine if concomitant anterior fundoplication reduces symptoms of reflux after myotomy without promoting dysphagia. From 1992 to 2004, 182 patients underwent laparoscopic Heller myotomy without fundoplication. After a prospective randomized trial justified its concomitant application, anterior fundoplication was undertaken with laparoscopic Heller myotomy in 171 patients from 2004 to 2007. All patients have been prospectively followed. Pre and postoperatively, patients scored the frequency and severity of symptoms of achalasia (including dysphagia, choking, vomiting, regurgitation, chest pain, and heartburn) using a Likert Scale (0 = never/not bothersome to 10 = always/very bothersome). Before myotomy, symptoms of achalasia were frequent and severe for all patients. After myotomy, the frequency and severity of all symptoms of achalasia significantly decreased for all patients (P < 0.001, Wilcoxon matched pairs test). Notably, relative to patients undergoing laparoscopic Heller myotomy alone, concomitant anterior fundoplication led to significantly less frequent and severe heartburn after myotomy (P < 0.05, Mann-Whitney Test) and to less frequent and severe dysphagia and choking (P < 0.05, Mann-Whitney Test). Laparoscopic Heller myotomy reduces the frequency and severity of symptoms of achalasia. Concomitant anterior fundoplication decreases the frequency and severity of heartburn and dysphagia after laparoscopic Heller myotomy. Concomitant anterior fundoplication promotes salutary relief in the frequency and severity of symptoms after myotomy and is warranted.

[Foreign body aspiration in children].

PubMed

Cohen, Shlomo; Goldberg, Shmuel; Springer, Chaim; Avital, Avraham; Picard, Elie

2015-03-01

Foreign body (FB) aspiration occurs mainly in children under 3 years of age and is one of the most frequent causes of accidental death under 12 months of age. The increased risk of FB aspiration in children is due to the different structure of the pharynx and the upper airways compared to adults. In addition, children have an immature swallowing mechanism and they most commonly aspirate food stuffs. FB aspiration is usually a sudden and dramatic event when the child feels that he is suffocating or choking. After the acute event, the clinical presentation widely ranges from severe respiratory distress to the most minimal symptoms. Bronchoscopy is the best diagnostic and therapeutic modality for FB inhalation. Prevention and rapid diagnosis can be lifesaving. In 2010, the American Academy of Pediatrics published a position paper on prevention of FB aspiration. The association calls for more proactive preventative measures to protect children from FB aspiration and to prevent mortality and morbidity. These include: 1. Raising awareness of parents and caregivers to supervise children and create a safe environment for them. 2. Promoting legislation and enforcing regulations that will prevent dangerous products being sold for children. 3. Changing the design of products, especially food products and toys, that will reduce the risks of choking. In this overview we will show the principles of diagnosis of FB aspiration and a flow chart including when flexible or rigid bronchoscopy is required.

Investigation of a L1-optimized choke ring ground plane for a low-cost GPS receiver-system

NASA Astrophysics Data System (ADS)

Zhang, Li; Schwieger, Volker

2018-01-01

Besides the geodetic dual-frequency GNSS receivers-systems (receiver and antenna), there are also low-cost single-frequency GPS receiver-systems. The multipath effect is a limiting factor of accuracy for both geodetic dual-frequency and low-cost single-frequency GPS receivers. And the multipath effect is for the short baselines dominating error (typical for the monitoring in Engineering Geodesy). So accuracy and reliability of GPS measurement for monitoring can be improved by reducing the multipath signal. In this paper, the self-constructed L1-optimized choke ring ground plane (CR-GP) is applied to reduce the multipath signal. Its design will be described and its performance will be investigated. The results show that the introduced low-cost single-frequency GPS receiver-system, which contains the Ublox LEA-6T single-frequency GPS receiver and Trimble Bullet III antenna with a self-constructed L1-optimized CR-GP, can reach standard deviations of 3 mm in east, 5 mm in north and 9 mm in height in the test field which has many reflectors. This accuracy is comparable with the geodetic dual-frequency GNSS receiver-system. The improvement of the standard deviation of the measurement using the CR-GP is about 50 % and 35 % compared to the used antenna without shielding and with flat ground plane respectively.

Combustion Dynamic Characteristics Identification in a 9-point LDI Combustor Under Choked Outlet Boundary Conditions

NASA Technical Reports Server (NTRS)

He, Zhuohui J.; Chang, Clarence T.

2017-01-01

Combustion dynamics data were collected at the NASA Glenn Research Center's CE-5 flame tube test facility under combustor outlet choked conditions. Two 9-point Swirl-Venturi Lean Direct Injection (SV-LDI) configurations were tested in a rectangular cuboid combustor geometry. Combustion dynamic data were measured at different engine operational conditions up to inlet air pressure and temperature of 24.13 bar and 828 K, respectively. In this study, the effects of acoustic cavity resonance, precessing vortex core (PVC), and non-uniform thermal expansion on the dynamic noise spectrum are identified by comparing the dynamic data that collected at various combustor inlet conditions along with combustor geometric calculations. The results show that the acoustic cavity resonance noises were seen in the counter-rotating pilot configuration but not in the co-rotating pilot configuration. Dynamic pressure noise band at around 0.9 kHz was only detected at the P'41 location (9.8 cm after fuel injector face) but not at the P'42 location (29 cm after the fuel injector face); the amplitude of this noise band depended on the thermal expansion ratio (T4/T3). The noise band at around 1.8 kHz was found to depend on the inlet air pressure or the air density inside the combustor. The PVC frequency was not observed in these two configurations.

Demonstrating the effect of forensic firearm countermeasures: Bullet characteristics generated due to barrel modifications.

PubMed

O'Keeffe, C; Champion, S; Allsop, D

2015-12-01

Forensic awareness and the declining availability of firearms have resulted in an increase in the use of modified and re-activated firearms in crime. Although some modifications are undertaken to simply acquire a functioning firearm, others are perpetrated as a direct forensic countermeasure to prevent the association between a firearm and a crime. This article describes the effects of these modifications on bullet striation patterns imparted from the barrel to a fired bullet. The key results indicated that the investigated modifications display assessable characteristics. The use of an oversized barrel imparted striations consistent with firing with the absence of typical rifling. Subsequent or consecutively fired bullets possessed striation variations, with the first showing the least evidence of striations. The application of a choke resulted in more obvious bullet elongation compared to a smoothbore barrel. The restriction caused merging of lands and groves of the imparted rifling and obscured their usual definition. Effects of breech adaption were also characterised by observing the buckling and enlargement of the cartridge case. This deformity of the cartridge case was most evident when the barrel pressure increased due to the presence of the choke. From this study it was evident that unique characteristic impressions associated with different modifications most commonly found in criminal investigations can be utilised by a forensic expert and impart significant intelligence to an investigation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

First aid skill retention of first responders within the workplace

PubMed Central

2011-01-01

Background Recent literature states that many necessary skills of CPR and first aid are forgotten shortly after certification. The purpose of this study was to determine the skill and knowledge decay in first aid in those who are paid to respond to emergency situations within a workplace. Methods Using a choking victim scenario, the sequence and accuracy of events were observed and recorded in 257 participants paid to act as first responders in large industrial or service industry settings. A multiple choice exam was also written to determine knowledge retention. Results First aid knowledge was higher in those who were trained at a higher level, and did not significantly decline over time. Those who had renewed their certificate one or more times performed better than those who had learned the information only once. During the choking scenario many skills were performed poorly, regardless of days since last training, such as hand placement and abdominal thrusts. Compressions following the victim becoming unconscious also showed classic signs of skill deterioration after 30 days. Conclusions As many skills deteriorate rapidly over the course of the first 90 days, changing frequency of certification is not necessarily the most obvious choice to increase retention of skill and knowledge. Alternatively, methods of regularly "refreshing" a skill should be explored that could be delivered at a high frequency - such as every 90 days. PMID:21303536

Incorporation of Environmental Features in Flood Control Channel Projects.

DTIC Science & Technology

1985-05-01

compacted subgrades, a layer of gravel or slag , and a 2- to 4-in. layer of concrete or asphalt. An innovative *. grassed-bituminous trail consisting of 6 in...of slag or crushed stone over a compacted subgrade was proposed for Chartiers Creek (Figure 66). 6" BLACK SLAG OR CRUSHED STONE. PENETRATE - WITH...ASPHALT EMULSION. CHOKE WITH 28 SLAG . BROOM THOROUGHLY INTO VOIDS - A MIXTURE OF ONE HALF (1/2) TOPSOIL AND ONE HALF (1/2) IB BLACK SLAG , AND SEED

Twin Jets Screech Suppression Concepts Tested for 4.7% Axisymmetric and Two-Dimensional Nozzle Configurations

DTIC Science & Technology

1990-09-29

for generating narrowband and 1 broadband shock-associated noise. Shoi .<-associated noise was first investigated by Powell who studied choked jet...for one configuration and one operating condition, but that one mode was always dominant over the others. For the axisymmetric case , two different...an NPR setting of 3.1 is shown in Figure 12. This data plot shows 14 narrowband peaks which is an extreme case . However, if on the average each data

Movements of Satellite-Tagged Blainville’s Beaked Whales Off the Island of Hawaii

DTIC Science & Technology

2009-01-01

Collective, 218 1⁄2 W. 4th Avenue, Olympia, Washington 98501, USA 2NOAA, Northwest Fisheries Science Center, 2725 Montlake Blvd E., Seattle, Washington...site of frequent sonar activity and was to be the site of choke point exer- cises during the 2006 Rim of the Pacific exercise. To date, no mass...Orcinus orca (Andrews et al. 2008). In 2006, satellite tags were deployed on 3 Blainville’s beaked whales, and, in 2008, we were able to deploy

A Literature Review - Problem Definition Studies on Selected Toxic Chemicals

DTIC Science & Technology

1978-06-16

2 III. Recommendations and Hazard Analysis 6 IV. Physical and Chemical Properties 8 V. Human Toxicity A. Conditions and Extent of Exposure - 16 B...40 H. Coral 41 I. Phytoplankton and Algae 42 J. Bacteria 44 K. Plants 46 1. Fruit Trees 46 2. Foliage 49 3. Vegetables 51 4. Aquatic Plants 52 j PACE...breathe may result. The lung condition may clear up or death may occur, especially in accidents when children drink and choke on diesel fuel. The

[Poisoning by household products].

PubMed

Lambert, H; Manel, J; Gabrion, I

2000-02-15

Caustic products are responsible for the most serious cases of poisoning, which are always emergency cases. Application of current intervention procedures has decreased both morbidity and mortality. Water-diluted bleach, the ingestion of which remains extremely frequent, is a moderate irritant rather than a caustic product. Emission of gas produced when mixing bleach with other agents can be responsible for choking gas poisoning. Anionic and nonionic detergents are mostly dangerous because of their foam-producing properties. Mercury vapours and methanol are other potentially hazardous products.

Aspects and applications of patched grid calculations

NASA Technical Reports Server (NTRS)

Walters, R. W.; Switzer, G. F.; Thomas, J. L.

1986-01-01

Patched grid calculations within the framework of an implicit, flux-vector split upwind/relaxation algorithm for the Euler equations are presented. The effect of a metric-discontinuous interface on the convergence rate of the algorithm is discussed along with the spatial accuracy of the solution and the effect of curvature along an interface. Results are presented and discussed for the free-stream problem, shock reflection problem, supersonic inlet with a 5 degree ramp, aerodynamically choked inlet, and three-dimensional analytic forebody.

A Study of the Vertical Component of Ocean Floor Vibrations in Two Geographical Chokepoints

DTIC Science & Technology

2017-05-30

Libby Reissued 30 May 2017 with Second Reader’s non -NPS affiliation added to title page. THIS PAGE INTENTIONALLY LEFT BLANK i REPORT DOCUMENTATION...choke points were considered to be a good representation of where these experimental bottom mounted sensors might be located should they be built...calibrated data, and the methodology used to get the calibrated data is discussed in detail. The results showed that one OBS out of the four was highly

Gust Response Analysis of a Turbine Cascade

NASA Technical Reports Server (NTRS)

Gorla, R. S. R.; Reddy, T. S. R.; Reddy, D. R.; Kurkov, A. P.

2001-01-01

A study was made of the gust response of an annular turbine cascade using a two-dimensional Navier Stokes code. The time-marching CFD code, NPARC, was used to calculate the unsteady forces due to the fluid flow. The computational results were compared with a previously published experimental data for the annular cascade reported in the literature. Reduced frequency, Mach number and angle of incidence were varied independently and the gust velocity was sinusoidal. For the high inlet velocity case, the cascade was nearly choked.

HSCT noise reduction technology development at GE Aircraft Engines

NASA Technical Reports Server (NTRS)

Majjigi, Rudramuni K.

1992-01-01

The topics covered include the following: High Speed Civil Transport (HSCT) exhaust nozzle design approaches; GE aircraft engine (GEAE) HSCT acoustics research; 2DCD non-IVP suppressor ejector; key sensitivities from reference aircraft; acoustic experiments; aero-mixing experimental set-up; fluid shield nozzle; HSCT Mach 2.4 flade nozzle; noise prediction; nozzle concept for GE/Boeing joint test; scale model hot core flow path modified to prevent hub-choking CFL3-D solution; HSCT exhaust nozzle status; and key acoustic technology issues for HSCT's.

HSCT noise reduction technology development at GE Aircraft Engines

NASA Astrophysics Data System (ADS)

Majjigi, Rudramuni K.

1992-04-01

The topics covered include the following: High Speed Civil Transport (HSCT) exhaust nozzle design approaches; GE aircraft engine (GEAE) HSCT acoustics research; 2DCD non-IVP suppressor ejector; key sensitivities from reference aircraft; acoustic experiments; aero-mixing experimental set-up; fluid shield nozzle; HSCT Mach 2.4 flade nozzle; noise prediction; nozzle concept for GE/Boeing joint test; scale model hot core flow path modified to prevent hub-choking CFL3-D solution; HSCT exhaust nozzle status; and key acoustic technology issues for HSCT's.

Turning Maneuver Limitations Imposed by Sudden Strut Side Ventilation on a 200-Ton 80-Knot Hydrofoil Craft

DTIC Science & Technology

1975-05-01

ventilated, but never supercavitating , for speeds up to 80 knots. In particular, choking of the air flow to the foil vent was not con- sidered. If this...4Conolly, A.C., "Experimental Investigations of Supercavitating Hydrofoils with Flaps," General Dynamics/Convair Report GD/C-63-210 (Dec 1963). 10 THE SIX...Dec 1966). 4. Conolly, A.C., "Experimenta, Investigations of Supercavitating Hydro- foils with Flaps," General Dynamics/Convair Report GD/C-63-210 (Dec

Quasi-one-dimensional compressible flow across face seals and narrow slots. 2: Computer program

NASA Technical Reports Server (NTRS)

Zuk, J.; Smith, P. J.

1972-01-01

A computer program is presented for compressible fluid flow with friction across face seals and through narrow slots. The computer program carries out a quasi-one-dimensional flow analysis which is valid for laminar and turbulent flows under both subsonic and choked flow conditions for parallel surfaces. The program is written in FORTRAN IV. The input and output variables are in either the International System of Units (SI) or the U.S. customary system.

A Systems Analysis View of the Vietnam War: 1965-1972. Volume 5. The Air War

DTIC Science & Technology

1975-02-18

effective, at least in the terms of truck kills, than our previous efforts. The table below shows attack sorties, enem truck sightings, and results...by heavy concentration of effort against anQ-bypassable choke points, the eney’a traffic flow can be interdacted effectively. Enem Truck Traffic in...following tentative conclusions. - The eneme receives about 70% of his msuplies fbr SW opera- S tions from sources inside SVW, 10% from Cambodia, and about

Oceanographic Effects on Maritime Threats: Mines and Oil Spills in the Strait of Hormuz

DTIC Science & Technology

2007-03-01

could potentially be used (Kreil, 2004). The full flow potential for all the pipelines together is about seven million barrels of oil a day... potential oil spills, and drift mining could mean the difference for a faster recovery from an incident at this choke point. The faster the clean...θ is potential temperature, g is the acceleration due to gravity, 1Λ is the dissipation length scale, , , and wu v′ ′ ′ denote the components

Photonic Choke-Joints for Dual Polarization Waveguides

NASA Technical Reports Server (NTRS)

Wollack, Edward J. (Inventor); U-Yen, Kongpop (Inventor); Chuss, David T. (Inventor)

2014-01-01

A waveguide structure for a dual polarization waveguide includes a first flange member, a second flange member, and a waveguide member disposed in each of the first flange member and second flange member. The first flange member and the second flange member are configured to be coupled together in a spaced-apart relationship separated by a gap. The first flange member has a substantially smooth surface, and the second flange member has an array of two-dimensional pillar structures formed therein.

The North Atlantic Treaty Organization and Libya: Reviewing Operation Unified Protector

DTIC Science & Technology

2013-06-01

Qaddafi appeared on state TV. He de- clared he was “in pain” about the removal of Tunisia President Ben Ali, and described the demonstrators as “led...only be- cause of large petrol resources but also the existence of maritime choke points and one of the most important world trade routes, it attracts... Tunisia Uprising,” The Guardian, January 16, 2011, available from www.guardian.co.uk/ world/2011/jan/16/muammar-gaddafi-condemns- tunisia -uprising

Compressible flow at high pressure with linear equation of state

NASA Astrophysics Data System (ADS)

Sirignano, William A.

2018-05-01

Compressible flow varies from ideal-gas behavior at high pressures where molecular interactions become important. Density is described through a cubic equation of state while enthalpy and sound speed are functions of both temperature and pressure, based on two parameters, A and B, related to intermolecular attraction and repulsion, respectively. Assuming small variations from ideal-gas behavior, a closed-form solution is obtained that is valid over a wide range of conditions. An expansion in these molecular-interaction parameters simplifies relations for flow variables, elucidating the role of molecular repulsion and attraction in variations from ideal-gas behavior. Real-gas modifications in density, enthalpy, and sound speed for a given pressure and temperature lead to variations in many basic compressible flow configurations. Sometimes, the variations can be substantial in quantitative or qualitative terms. The new approach is applied to choked-nozzle flow, isentropic flow, nonlinear-wave propagation, and flow across a shock wave, all for the real gas. Modifications are obtained for allowable mass-flow through a choked nozzle, nozzle thrust, sonic wave speed, Riemann invariants, Prandtl's shock relation, and the Rankine-Hugoniot relations. Forced acoustic oscillations can show substantial augmentation of pressure amplitudes when real-gas effects are taken into account. Shocks at higher temperatures and pressures can have larger pressure jumps with real-gas effects. Weak shocks decay to zero strength at sonic speed. The proposed framework can rely on any cubic equation of state and be applied to multicomponent flows or to more-complex flow configurations.

Introduction of new food textures during complementary feeding: Observations in France.

PubMed

Marduel Boulanger, A; Vernet, M

2018-01-01

Complementary feeding plays a crucial role in the development of infants and toddlers and studies suggest benefits specific to the introduction of food textures. Evaluate the recommendations given to parents, their practices, and their attitudes towards the introduction of food textures during complementary feeding in France. This was a cross-sectional pilot study conducted in 2013. One hundred and eighty-one parents with at least one child aged 6-36 months living in France completed an ad hoc questionnaire. Eighty-eight percent of the parents surveyed received oral information on complementary feeding, but only 46% received such information on the introduction of food textures. Pediatricians were the most frequently listed source of oral information on complementary feeding. More than half the parents also looked for additional information in books and on the internet. While oral recommendations matched parents' practices, they seemed to occur at a later age compared to infants' physiological ability to handle new textures. The quality of information on food texture advice available in paper and electronic formats evaluated using a 4-point scale was found to be limited. Introducing new food texture was spontaneously reported as the most common difficulty in complementary feeding (16%). Fear of choking when first introducing food pieces was reported by 54% of the parents. The parents' lack of information on the introduction of food textures, as well as their fear that their child may choke, should encourage providing new recommendations in France. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Fabrication of Feedhorn-Coupled Transition Edge Sensor Arrays for Measurement of the Cosmic Microwave Background Polarization

NASA Technical Reports Server (NTRS)

Denis, K. L.; Ali, A.; Appel, J.; Bennett, C. L.; Chang, M. P.; Chuss, D. T.; Colazo, F. A.; Costen, N.; Essinger-Hileman, T.; Hu, R.;

Fabrication of Feedhorn-Coupled Transition Edge Sensor Arrays for Measurement of the Cosmic Microwave Background Polarization

NASA Technical Reports Server (NTRS)

Denis, Kevin L.; Aamir, A.; Bennett, C. L.; Chang, M. P.; Chuss, D. T.; Colazo, F. A.; Costen, N.; Essinger-Hileman, T.; Hu, R.; Marriage, T.;

Ignition and Performance Tests of Rocket-Based Combined Cycle Propulsion System

NASA Technical Reports Server (NTRS)

Anderson, William E.

2005-01-01

The ground testing of a Rocket Based Combined Cycle engine implementing the Simultaneous Mixing and Combustion scheme was performed at the direct-connect facility of Purdue University's High Pressure Laboratory. The fuel-rich exhaust of a JP-8/H2O2 thruster was mixed with compressed, metered air in a constant area, axisymmetric duct. The thruster was similar in design and function to that which will be used in the flight test series of Dryden's Ducted-Rocket Experiment. The determination of duct ignition limits was made based on the variation of secondary air flow rates and primary thruster equivalence ratios. Thrust augmentation and improvements in specific impulse were studied along with the pressure and temperature profiles of the duct to study mixing lengths and thermal choking. The occurrence of ignition was favored by lower rocket equivalence ratios. However, among ignition cases, better thrust and specific impulse performance were seen with higher equivalence ratios owing to the increased fuel available for combustion. Thrust and specific impulse improvements by factors of 1.2 to 1.7 were seen. The static pressure and temperature profiles allowed regions of mixing and heat addition to be identified. The mixing lengths were found to be shorter at lower rocket equivalence ratios. Total pressure measurements allowed plume-based calculation of thrust, which agreed with load-cell measured values to within 6.5-8.0%. The corresponding Mach Number profile indicated the flow was not thermally choked for the highest duct static pressure case.

Braided Carbon Fiber Rope Flow Characteristics. Degree awarded by Utah Univ.

NASA Technical Reports Server (NTRS)

Heman, J. R. C.; McCool, A. (Technical Monitor)

2000-01-01

I am submitting the following technical subject for consideration as a thesis topic for the master degree: The reusable solid rocket motor (RSRM) nozzle internal joints are being evaluated for the incorporation of a carbon fiber rope (CFR) as a thermal barrier. The CFR is approximately 0.260 in. diameter and is composed of approximately 12,000 carbon fibers, woven in ten sheaths or layers. The CFR is manufactured by a sub-tier vendor and subsequently several of its manufacturing details are proprietary to that vendor. The CFR design intent is to prevent hot motor combustion products and slag from intruding into the joint scaling area while still approaching a vented joint design to avoid the detriments of gas jet impingement. As a member of the Heat Transfer section at Thiokol Propulsion, two main goals exist as part of this NASA funded design effort: (1) development of flow model through the CFR and (2) development of a heat transfer model through the CFR. While both models are needed and most probably interrelated, the gas flow model is being targeted as the subject matter. Essentially, the topic would be "Modeling of Gas Flow through a Braided Carbon Fiber Rope". An AIAA journal or conference paper is being considered through Thiokol/NASA as well. A sub-scale CFR flow test fixture was designed to simulate the relative levels of CFR compression. The test fixture provides the means to measure gas mass flow rate upstream of the CFR and the pressure and temperature both upstream and downstream of the CFR. The test fixture was designed to eliminate the possibility of dynamic gapping at the CFR location and provide minimal flow resistance to ambient for gases exiting the rope. The data collected in the experiment will be evaluated to define a permeability/flow resistance model. Two possibilities exist for the flow characteristics through the CFR from choked flow to strictly friction driven. A test matrix for evaluating the CFR has been compiled, which addresses both of these characteristics. The range of pressures to be tested covers a relatively low delta pressure where non-choked flow is impossible, while the high pressure shown is dictated by the RSRM joint operating pressure where choking is possible. The test matrix, was also designed for a range of rope compressions or test fixture gaps ranging from 0.025" to 0.070". These gaps are controlled by the range of RSRM full-scale hardware joint gaps that will be expected by virtue of the joint design.

Choked flow of fluid nitrogen with emphasis on the thermodynamic critical region

NASA Technical Reports Server (NTRS)

Hendricks, R. C.; Simoneau, R. J.; Ehlers, R. C.

1972-01-01

Experimental measurements of critical flow rate and pressure ratio for nitrogen flowing through a nozzle are presented. Data for selected stagnation isotherms from 87.5 to 234 K with pressures to 9.3 MN/m2 are compared to an equilibrium model with real fluid properties and also a nonequilibrium model. Critical flow pressure ratio along an isotherm tends to peak while the flow rate indicates an inflection. The point is closely associated with the transposed critical temperature and represents a change in the fluid structure.

Creating a new investment pool for innovative health systems research.

PubMed

Laba, Tracey-Lea; Patel, Anushka; Jan, Stephen

2017-05-01

Recent trends in health research funding towards 'safe bets' is discouraging investment into the development of health systems interventions and choking off a vital area of policy-relevant research. This paper argues that to encourage investment into innovative and perceivably riskier health systems research, researchers need to create more attractive business cases by exploring alternative approaches to the design and evaluation of health system interventions. At the same time, the creation of dedicated funding opportunities to support this work, as well as for relevant early career researchers, is needed.

Obesity and Obstructive Sleep Apnea: Or is it OSA and Obesity?

DTIC Science & Technology

2008-01-01

sleep apnea syn- drome on serum aminotransferase levels in obese patients, Am. J. Med. 114 (2003) 370...code) A o g t c e i b r a m P K 1 b d s p d g t s m t b R T 0 d Pathophysiology 15 (2008) 71–77 Obesity and obstructive sleep apnea : Or is it OSA and...accepted 30 April 2008 bstract Obstructive sleep apnea (OSA) consists of repetitive choking spells due to sleep -induced reduction of upper airway

Nonlinear wave choked inlets

NASA Technical Reports Server (NTRS)

1979-01-01

The quasi-one dimensional flow program was modified in two ways. The Runge-Kutta subroutine was replaced with a subroutine which used a modified divided difference form of the Adams Pece method and the matrix inversion routine was replaced with a pseudo inverse routine. Calculations were run using both the original and modified programs. Comparison of the calculations showed that the original Runge-Kutta routine could not detect singularity near the throat and was integrating across it. The modified version was able to detect the singularity and therefore gave more valid calculations.

A rare fatality due to calcified stylohyoid ligament (Eagle syndrome).

PubMed

Gupta, Avneesh; Aggrawal, Anil; Setia, Puneet

2017-06-01

The elongation or calcification of the stylohyoid ligament that leads to pressure symptoms, or entrapment of nearby glossopharyngeal nerve or carotid artery, is known as Eagle syndrome. A PubMed search leads to finding of rare fatality among the 49 reported cases. In the present case, the deceased was a 40-year-old male who choked on his food. We hypothesise that the impaction of food in the upper respiratory tract, as well as the inability to intubate the person, were both the result of the calcified stylohyoid ligament.

Experimental performance of a 16.10-centimeter-tip-diameter sweptback centrifugal compressor designed for a 6:1 pressure ratio

NASA Technical Reports Server (NTRS)

Klassen, H. A.; Wood, J. R.; Schumann, L. F.

1977-01-01

A backswept impeller with design mass flow rate of 1.033 kg/sec was tested with both a vaned diffuser and a vaneless diffuser to establish stage and impeller characteristics. Design stage pressure ratio of 5.9:1 was attained at a flow slightly lower than the design value. Flow range at design speed was 6 percent of choking flow. Impeller axial tip clearance at design speed was varied to determine effect on stage and impeller performance.

Hydrogen and sulfur recovery from hydrogen sulfide wastes

DOEpatents

Harkness, J.B.L.; Gorski, A.J.; Daniels, E.J.

1993-05-18

A process is described for generating hydrogen and elemental sulfur from hydrogen sulfide waste in which the hydrogen sulfide is [dis]associated under plasma conditions and a portion of the hydrogen output is used in a catalytic reduction unit to convert sulfur-containing impurities to hydrogen sulfide for recycle, the process also including the addition of an ionizing gas such as argon to initiate the plasma reaction at lower energy, a preheater for the input to the reactor and an internal adjustable choke in the reactor for enhanced coupling with the microwave energy input.

Hydrogen and sulfur recovery from hydrogen sulfide wastes

DOEpatents

Harkness, John B. L.; Gorski, Anthony J.; Daniels, Edward J.

1993-01-01

A process for generating hydrogen and elemental sulfur from hydrogen sulfide waste in which the hydrogen sulfide is associated under plasma conditions and a portion of the hydrogen output is used in a catalytic reduction unit to convert sulfur-containing impurities to hydrogen sulfide for recycle, the process also including the addition of an ionizing gas such as argon to initiate the plasma reaction at lower energy, a preheater for the input to the reactor and an internal adjustable choke in the reactor for enhanced coupling with the microwave energy input.

Method and apparatus for reducing the harmonic currents in alternating-current distribution networks

DOEpatents

Beverly, Leon H.; Hance, Richard D.; Kristalinski, Alexandr L.; Visser, Age T.

1996-01-01

An improved apparatus and method reduce the harmonic content of AC line and neutral line currents in polyphase AC source distribution networks. The apparatus and method employ a polyphase Zig-Zag transformer connected between the AC source distribution network and a load. The apparatus and method also employs a mechanism for increasing the source neutral impedance of the AC source distribution network. This mechanism can consist of a choke installed in the neutral line between the AC source and the Zig-Zag transformer.

Method and apparatus for reducing the harmonic currents in alternating-current distribution networks

DOEpatents

Beverly, L.H.; Hance, R.D.; Kristalinski, A.L.; Visser, A.T.

1996-11-19

An improved apparatus and method reduce the harmonic content of AC line and neutral line currents in polyphase AC source distribution networks. The apparatus and method employ a polyphase Zig-Zag transformer connected between the AC source distribution network and a load. The apparatus and method also employs a mechanism for increasing the source neutral impedance of the AC source distribution network. This mechanism can consist of a choke installed in the neutral line between the AC source and the Zig-Zag transformer. 23 figs.

Numerical flow analysis of axial flow compressor for steady and unsteady flow cases

NASA Astrophysics Data System (ADS)

Prabhudev, B. M.; Satish kumar, S.; Rajanna, D.

2017-07-01

Performance of jet engine is dependent on the performance of compressor. This paper gives numerical study of performance characteristics for axial compressor. The test rig is present at CSIR LAB Bangalore. Flow domains are meshed and fluid dynamic equations are solved using ANSYS package. Analysis is done for six different speeds and for operating conditions like choke, maximum efficiency & before stall point. Different plots are compared and results are discussed. Shock displacement, vortex flows, leakage patterns are presented along with unsteady FFT plot and time step plot.

Sugar Dehydration without Sulfuric Acid: No More Choking Fumes in the Classroom!

NASA Astrophysics Data System (ADS)

Silverstein, Todd P.; Zhang, Yi

1998-06-01

Sugar is a common reagent often used in colorful classroom demonstrations. It produces a growing column of black ash when dehydrated by concentrated sulfuric acid, and it produces a brilliant purple flame when combusted with potassium chlorate. Unfortunately, both of these reactions also produce copious quantities of noxious fumes which make them problematic as lecture demonstrations. We have modified and combined these two reactions. Our demonstration uses no sulfuric acid, yields relatively little smoke, and produces an exciting and unpredictable growing column of black carbon.

The upper pouch in oesophageal atresia shows proportional growth during late fetal life.

PubMed

Tröbs, R B; Nissen, M; Wald, J

2018-05-12

Oesophageal atresia with trachea-oesophageal fistula is a rare foregut malformation that requires surgery soon after birth. Prenatal ultrasound diagnosis is based on the presence of polyhydramnios, a small or non-visible fetal stomach and the blind ending oesophagus, called the upper pouch (1). Neonates present with salivation, coughing, choking and attacks of cyanosis. A diagnosis of oesophageal atresia is confirmed by inserting a nasogastric tube and a thoraco-abdominal X-ray. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Laparoscopic Heller myotomy for achalasia: results after 10 years.

PubMed

Cowgill, Sarah M; Villadolid, Desiree; Boyle, Robert; Al-Saadi, Sam; Ross, Sharona; Rosemurgy, Alexander S

2009-12-01

Laparoscopic Heller myotomy was first undertaken in the early 1990s, and appreciable numbers of patients with 10-year follow-up periods are now available. This study was undertaken to determine long-term outcomes after laparoscopic Heller myotomy used to treat achalasia. Of 337 patients who have undergone laparoscopic Heller myotomy since 1992, 47 who underwent myotomy more than 10 years ago have been followed through a prospectively maintained registry. Among many symptoms, patients scored dysphagia, chest pain, vomiting, regurgitation, choking, and heartburn before and after myotomy using a Likert scale with choices ranging from 0 (never/not bothersome) to 10 (always/very bothersome). Symptom scores before and after myotomy were compared using a Wilcoxon matched-pairs test. Data are reported as median (mean ± standard deviation). The median length of the hospital stay was 2 days (mean, 3 ± 8.6 days; range, 1-60 days). Notable complications were infrequent after myotomy. There were no perioperative deaths. One patient required a redo myotomy after 5 years due to recurrence of symptoms. At this writing, 33 patients (70%) are still alive. The causes of death after discharge were unrelated to myotomy. The frequency and severity scores for dysphagia, chest pain, vomiting, regurgitation, choking, and heartburn all decreased significantly after laparoscopic Heller myotomy (p < 0.0001 for all). Laparoscopic Heller myotomy can be undertaken with few complications. This procedure significantly decreases the frequency and severity of achalasia symptoms without promoting heartburn. The symptoms of achalasia are durably ameliorated by laparoscopic Heller myotomy during long-term follow-up evaluation, thereby promoting application of this procedure.

Indications for and factors relating to outcome after rumenotomy or rumenostomy in cattle: 95 cases (1999-2011).

PubMed

Hartnack, Amanda K; Niehaus, Andrew J; Rousseau, Marjolaine; Pentecost, Rebecca L; Miesner, Matt D; Anderson, David E

2015-09-15

To evaluate indications for and factors relating to outcome after rumenotomy or rumenostomy in cattle. Retrospective case series. 95 cattle that underwent rumenotomy or rumenostomy. Medical records for 95 cattle that underwent either rumenostomy or rumenotomy at 2 veterinary teaching hospitals in 1999 through 2011 were analyzed. Reasons for the procedures were noted. Long-term outcome was determined during telephone interviews with owners. 42 (44%) bovids underwent rumenostomy and 53 (56%) bovids underwent rumenotomy. Among the 42 animals undergoing rumenostomy, 18 (43%) had rumen cannulas placed during elective procedures. Other indications for rumenostomy included ruminal tympany (bloat [n = 20]), esophageal obstruction (choke [1]), grain overload (1), and provision of access for administration of enteral nutrition (2). Indications for rumenotomy included traumatic reticuloperitonitis (n = 31), bloat (9), foreign body (6), choke (5), and other (2). Long-term follow-up data were available for 31 of 42 (74%) bovids that underwent rumenostomy. Of those 31 animals, 17 (55%) were still in the herd, 4 (13%) had been culled, and 10 (32%) had died or were euthanized. Long-term follow-up data were available for 38 of 53 (72%) bovids that underwent rumenotomy. Of those 38 animals, 13 (34%) were still in the herd, 14 (37%) had been culled, and 11 (29%) had died or been euthanized. Results indicated that rumenotomy and rumenostomy can be effective in treating or relieving complications secondary to forestomach disorders in cattle. Bovids undergoing rumen surgery had a favorable prognosis for survival and a fair prognosis for potential return to production.

Evaluation of diagnostic criteria for panic attack using item response theory: findings from the National Comorbidity Survey in USA.

PubMed

Ietsugu, Tetsuji; Sukigara, Masune; Furukawa, Toshiaki A

2007-12-01

The dichotomous diagnostic systems such as the Diagnostic and Statistical Manual of Mental Disorders (DSM) and International Classification of Diseases (ICD) lose much important information concerning what each symptom can offer. This study explored the characteristics and performances of DSM-IV and ICD-10 diagnostic criteria items for panic attack using modern item response theory (IRT). The National Comorbidity Survey used the Composite International Diagnostic Interview to assess 14 DSM-IV and ICD-10 panic attack diagnostic criteria items in the general population in the USA. The dimensionality and measurement properties of these items were evaluated using dichotomous factor analysis and the two-parameter IRT model. A total of 1213 respondents reported at least one subsyndromal or syndromal panic attack in their lifetime. Factor analysis indicated that all items constitute a unidimensional construct. The two-parameter IRT model produced meaningful and interpretable results. Among items with high discrimination parameters, the difficulty parameter for "palpitation" was relatively low, while those for "choking," "fear of dying" and "paresthesia" were relatively high. Several items including "dry mouth" and "fear of losing control" had low discrimination parameters. The item characteristics of diagnostic criteria among help-seeking clinical populations may be different from those that we observed in the general population and deserve further examination. "Paresthesia," "choking" and "fear of dying" can be thought to be good indicators of severe panic attacks, while "palpitation" can discriminate well between cases and non-cases at low level of panic attack severity. Items such as "dry mouth" would contribute less to the discrimination.

Pediatric First Aid Practices in Ghana: A Population-Based Survey.

PubMed

Gyedu, Adam; Mock, Charles; Nakua, Emmanuel; Otupiri, Easmon; Donkor, Peter; Ebel, Beth E

2015-08-01

Children in low- and middle-income countries (LMIC) often receive care outside the formal medical sector. Improving pre-hospital first aid has proven to be highly cost-effective in lowering trauma mortality. Few studies in LMIC have examined home first aid practices for injured children. We conducted a representative population-based survey of 200 caregivers of children under 18 years of age, representing 6520 households. Caregivers were interviewed about their first aid practices and care-seeking behaviors when a child sustained an injury at home. Injuries of interest included burns, lacerations, fractures and choking. Reported practices were characterized as recommended, low-risk, and potentially harmful. For common injuries, 75-96% of caregivers reported employing a recommended practice (e.g., running cool water over a burn injury). However, for these same injuries, 13-61% of caregivers also identified potentially harmful management strategies (e.g., applying sand to a laceration). Choking had the highest proportion (96%) of recommended first aid practice: (e.g., hitting the child's back) and the lowest percent (13%) of potentially harmful practices (e.g., attempting manual removal). Fractures had the lowest percent (75%) of recommended practices (e.g., immediately bringing the child to a health facility). Burns had the highest percent (61%) of potentially harmful practices (e.g., applying kerosene). While most caregivers were aware of helpful first aid practices to administer for a child injury, many parents also described potentially harmful practices or delays in seeking medical attention. As parents are the de facto first responders to childhood injury, there are opportunities to strengthen pre-hospital care for children in LMICs.

Impact of Education on School-aged Children's Knowledge of and Participation in "The Choking Game".

PubMed

Butler, Kendall; Raingruber, Bonnie; Butler, Eric; Wilson, Machelle

2016-06-01

To better understand school-aged children's awareness of and attitudes about the Choking Game (TCG). To determine if education can increase awareness of the risk of injury when playing TCG and to determine if education can decrease interest in TCG participation. Anonymous pre- and post-education surveys. Two middle/high schools; one in Utah and one in California. 291 participants (163 in Utah, 128 in California) aged 9-18, 68% under age 15, 32% 15 and older; 65% white, 35% non-white; 52% female, 48% male. 76% of participants knew about TCG, of those 62% heard about it at school. 32% knew someone who had played, and twelve (4%) had played, usually with others. Most frequently cited as reasons for participation were curiosity, peer pressure, and competition. School was the most common location for playing. In California education significantly increased risk awareness, and significant positive attitude changes were observed regarding interest in playing TCG. Utah participants also exhibited attitude changes in the desired direction (less interest in playing TCG, would warn friends, and realized it was not safe to stop breathing), although results were not statistically significant, possibly due to previous education and four recent and highly publicized TCG deaths in the community. Results indicate that interactive, standardized, and skills-based education can increase student awareness of TCG risks and decrease interest in participation. Students reported that the schools were often where they first heard about TCG and where TCG was commonly played. Educators and associated health care professionals should therefore be encouraged to provide preventative education as part of school curricula.

The Effects of Metallized Fuel Composition on the Combustion Characteristics of Solid Fuel Ramjets

DTIC Science & Technology

1986-12-01

Heater. convening nozzle. As the air was passing through the choked flow nozzle, P r and T t were meassured . Using these measurements the computation of...4 1.12 30 .22 -/- No ignition 4 0.95 43 .20 -/100 1106 Ignition and sustain NWC-5 4 0.95 45 .20 -/67 1052 Ignition. Hard to sustain. NWC-6 1 0.95 52...NUMBER REF. # TABLE 5 in ONLY psia lbm IGNIT./SUST. psia °Rs-in 2 0.95 41 .20 -/75 1125 Ignition. Hard to sustain. NWC-11 3 0.75 62 .20 -/140 1055 Good

An experimental investigation of ejector performance based upon different refrigerants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, S.L.; Yen, J.Y.; Huang, M.C.

1998-12-31

This article experimentally compares the characteristics of different refrigerants as the working fluid in an ejector cooling system. The study covers common refrigerants including R-113, R-114, R-142b, and R-718. The critical choking conditions against the variation of condenser back pressure, the evaporator pressure, and the generator pressure are determined for each refrigerant. The results are compiled into a convenient performance curve and COP chart. These results can serve as an important reference for future design of ejector cooling systems. Finally, this paper presents a comparison of the performances of different refrigerants in an ejector cooling system.

Mach disk from underexpanded axisymmetric nozzle flow

NASA Technical Reports Server (NTRS)

Chang, I.-S.; Chow, W. L.

1974-01-01

The flowfield associated with the underexpanded axisymmetric nozzle freejet flow including the appearance of a Mach disk has been studied. It is shown that the location and size of the Mach disk are governed by the appearance of a triple-point shock configuration and the condition that the central core flow will reach a state of 'choking at a throat'. It is recognized that coalescence of waves requires special attention and the reflected wave, as well as the vorticity generated from these wave interactions, have to be taken accurately into account. The theoretical results obtained agreed well with the experimental data.

Device for improved air and fuel distribution to a combustor

DOEpatents

Laster, Walter R.; Schilp, Reinhard

2016-05-31

A flow conditioning device (30, 50, 70, 100, 150) for a can annular gas turbine engine, including a plurality of flow elements (32, 34, 52, 54, 72, 74, 102) disposed in a compressed air flow path (42, 60, 80, 114, 122) leading to a combustor (12), configured such that relative adjustment of at least one flow directing element (32, 52, 72, 110) with respect to an adjacent flow directing element (34, 54, 74, 112, 120) during operation of the gas turbine engine is effective to adjust a level of choking of the compressed air flow path (42, 60, 80, 114, 122).

Maxime A. Faget Portrait

NASA Image and Video Library

1953-02-18

L59-1497-6 Maxime A. Faget was born in British Honduras in 1921, the son of an honored physician of the U.S. Public Health Service. In 1943 he earned a B.S. in mechanical engineering from Louisiana State University. After service as a navy submarine officer, he joined the Langley staff in 1946 as a member of the Pilotless Aircraft Research Division. His early work for PARD involved the invention of choking inlets for ramjets and a flight Mach meter. Photograph published in Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917-1958 by James R. Hansen. Page 379.

Laboratory simulation of meteoritic noble gases. III - Sorption of neon, argon, krypton, and xenon on carbon - Elemental fractionation

NASA Technical Reports Server (NTRS)

Wacker, John F.

1989-01-01

The sorption of Ne, Ar, Kr, and Xe was studied in carbon black, acridine carbon, and diamond in an attempt to understand the origin of trapped noble gases in meteorites. The results support a model in which gases are physically adsorbed on interior surfaces formed by a pore labyrinth within amorphous carbons. The data show that: (1) the adsorption/desorption times are controlled by choke points that restrict the movement of noble gas atoms within the pore labyrinth, and (2) the physical adsorption controls the temperature behavior and elemental fractionation patterns.

Experimental research of flow servo-valve

NASA Astrophysics Data System (ADS)

Takosoglu, Jakub

Positional control of pneumatic drives is particularly important in pneumatic systems. Some methods of positioning pneumatic cylinders for changeover and tracking control are known. Choking method is the most development-oriented and has the greatest potential. An optimal and effective method, particularly when applied to pneumatic drives, has been searched for a long time. Sophisticated control systems with algorithms utilizing artificial intelligence methods are designed therefor. In order to design the control algorithm, knowledge about real parameters of servo-valves used in control systems of electro-pneumatic servo-drives is required. The paper presents the experimental research of flow servo-valve.

Safe Kids Worldwide: preventing unintentional childhood injuries across the globe.

PubMed

Mickalide, Angela; Carr, Kate

2012-12-01

Unintentional injuries are predictable and preventable. Yet every hour, a child in the United States dies from an unintentional injury. Globally, the number is even more staggering, with nearly 1 million children dying from unintentional injuries each year. Motor vehicle-related injuries, burns, drowning, falls, suffocation or choking, and poisoning are just a few of the unintentional injury risks threatening children. Patient safety requires a three-pronged strategy of behavior change, use of safety devices, and improvement of laws and regulations to ensure that all children lead healthy and productive lives. Copyright © 2012 Elsevier Inc. All rights reserved.

What Happens If They Say No? Preserving Access to Critical Commercial Space Capabilities during Future Crises

DTIC Science & Technology

2014-12-01

SatelliteShortagesMayChokeOffMilitaryDroneExpansion.aspx; G. Ryan Faith and Mariel John , “Space Report 2011” in Authoritative Guide to Global Space Activity,” ed. Micah Walter-Range (Colorado Springs...Werner, “Cover Story”; John Walcott, “Chinese Espionage Campaign Targets U.S. Space Technology,” Bloomberg, 18 April 2012, http://www.bloomberg.com...frus1969-76v25.pdf; Walter J. Boyne , The Two O’Clock War: The 1973 Yom Kippur Conflict and the Airlift That Saved Israel, 1st ed. (New York: Thomas

Operating Characteristics of the Multiple Critical Venturi System and Secondary Calibration Nozzles Used for Weight-Flow Measurements in the Langley 16-Foot Transonic Tunnel

NASA Technical Reports Server (NTRS)

Berrier, B. L.; Leavitt, L. D.; Bangert, L. S.

1985-01-01

An investigation has been conducted in the Langley 16 Foot Transonic Tunnel to determine the weight flow measurement characteristics of a multiple critical Venturi system and the nozzle discharge coefficient characteristics of a series of convergent calibration nozzles. The effects on model discharge coefficient of nozzle throat area, model choke plate open area, nozzle pressure ratio, jet total temperature, and number and combination of operating Venturis were investigated. Tests were conducted at static conditions (tunnel wind off) at nozzle pressure ratios from 1.3 to 7.0.

Subsonic Performance of Ejector Systems

NASA Astrophysics Data System (ADS)

Weil, Samuel

Combined cycle engines combining scramjets with turbo jets or rockets can provide efficient hypersonic flight. Ejectors have the potential to increase the thrust and efficiency of combined cycle engines near static conditions. A computer code was developed to support the design of a small-scale, turbine-based combined cycle demonstrator with an ejector, built around a commercially available turbojet engine. This code was used to analyze the performance of an ejector system built around a micro-turbojet. With the use of a simple ejector, net thrust increases as large as 20% over the base engine were predicted. Additionally the specific fuel consumption was lowered by 10%. Increasing the secondary to primary area ratio of the ejector lead to significant improvements in static thrust, specific fuel consumption (SFC), and propulsive efficiency. Further ejector performance improvements can be achieved by using a diffuser. Ejector performance drops off rapidly with increasing Mach number. The ejector has lower thrust and higher SFC than the turbojet core at Mach numbers above 0.2. When the nozzle chokes a significant drop in ejector performance is seen. When a diffuser is used, higher Mach numbers lead to choking in the mixer and a shock in the nozzle causing a significant decrease in ejector performance. Evaluation of different turbo jets shows that ejector performance depends significantly on the properties of the turbojet. Static thrust and SFC improvements can be achieved with increasing ejector area for all engines, but size of increase and change in performance at higher Mach numbers depend heavily on the turbojet. The use of an ejector in a turbine based combined cycle configuration also increases performance at static conditions with a thrust increase of 5% and SFC decrease of 5% for the tested configuration.

Progress of High Efficiency Centrifugal Compressor Simulations Using TURBO

NASA Technical Reports Server (NTRS)

Kulkarni, Sameer; Beach, Timothy A.

2017-01-01

Three-dimensional, time-accurate, and phase-lagged computational fluid dynamics (CFD) simulations of the High Efficiency Centrifugal Compressor (HECC) stage were generated using the TURBO solver. Changes to the TURBO Parallel Version 4 source code were made in order to properly model the no-slip boundary condition along the spinning hub region for centrifugal impellers. A startup procedure was developed to generate a converged flow field in TURBO. This procedure initialized computations on a coarsened mesh generated by the Turbomachinery Gridding System (TGS) and relied on a method of systematically increasing wheel speed and backpressure. Baseline design-speed TURBO results generally overpredicted total pressure ratio, adiabatic efficiency, and the choking flow rate of the HECC stage as compared with the design-intent CFD results of Code Leo. Including diffuser fillet geometry in the TURBO computation resulted in a 0.6 percent reduction in the choking flow rate and led to a better match with design-intent CFD. Diffuser fillets reduced annulus cross-sectional area but also reduced corner separation, and thus blockage, in the diffuser passage. It was found that the TURBO computations are somewhat insensitive to inlet total pressure changing from the TURBO default inlet pressure of 14.7 pounds per square inch (101.35 kilopascals) down to 11.0 pounds per square inch (75.83 kilopascals), the inlet pressure of the component test. Off-design tip clearance was modeled in TURBO in two computations: one in which the blade tip geometry was trimmed by 12 mils (0.3048 millimeters), and another in which the hub flow path was moved to reflect a 12-mil axial shift in the impeller hub, creating a step at the hub. The one-dimensional results of these two computations indicate non-negligible differences between the two modeling approaches.

Brazilian dentists' attitudes about medical emergencies during dental treatment.

PubMed

Arsati, Franco; Montalli, Victor Angelo; Flório, Flavia Martão; Ramacciato, Juliana Cama; da Cunha, Fernanda Lopes; Cecanho, Rodrigo; de Andrade, Eduardo Dias; Motta, Rogério Heládio Lopes

2010-06-01

The main objective of this study was to evaluate the prevalence of emergencies in dental practices and the prepared-ness and the training experience in cardiopulmonary resuscitation (CPR) of Brazilian dentists in dealing with emergencies. The volunteer participants in the study were 498 Brazilian dentists who were present at the 27th International Congress of Dentistry in São Paulo. The most prevalent emergency was presyncope (reported by 54.20 percent of respondents), followed by orthostatic hypotension (44.37 percent), moderate allergic reactions (16.86 percent), hypertensive crisis (15.06 percent), asthma (15.06 percent), syncope (12.65 percent), angina (6.82 percent), convulsion (6.22 percent), hypoglycemia (5.62 percent), hyperventilation crisis (5.22 percent), choking (2.20 percent), and cerebrovascular accident (0.8 percent). Anaphylaxis, myocardial infarction, and cardiac arrest were the rarest emergencies, reported by only 0.4, 0.2, and 0.2 percent of dentists, respectively. Only 41 percent of the dentists judged themselves capable to diagnose the cause of an emergency during a dental visit. The majority responded that they would be capable of performing initial treatment of presyncope, syncope, orthostatic hypotension, convulsion, and choking. However, most of them felt unable to treat anaphylaxis, myocardial infarction, or cardiac arrest. Further, the majority felt unable to perform CPR or undertake an intravenous injection. It was concluded that the most prevalent medical emergencies in dental practice of Brazilian dentists are presyncope and orthostatic hypotension. The occurrence of life-threatening medical emergencies like anaphylaxis, myocardial infarction, cardiac arrest, and cerebrovascular accident is rare. Brazilian dentists are not fully prepared to manage medical emergencies and have insufficient experience training in CPR.

Investigation of the aerothermodynamics of hypervelocity reacting flows in the ram accelerator

NASA Technical Reports Server (NTRS)

Hertzberg, A.; Bruckner, A. P.; Mattick, A. T.; Knowlen, C.

1992-01-01

New diagnostic techniques for measuring the high pressure flow fields associated with high velocity ram accelerator propulsive modes was experimentally investigated. Individual propulsive modes are distinguished by their operating Mach number range and the manner in which the combustion process is initiated and stabilized. Operation of the thermally choked ram accelerator mode begins by injecting the projectile into the accelerator tube at a prescribed entrance velocity by means of a conventional light gas gun. A specially designed obturator, which is used to seal the bore of the gun, plays a key role in the ignition of the propellant gases in the subsonic combustion mode of the ram accelerator. Once ignited, the combustion process travels with the projectile and releases enough heat to thermally choke the flow within several tube diameters behind it, thereby stabilizing a high pressure zone on the rear of the projectile. When the accelerating projectile approaches the Chapman-Jouguet detonation speed of the propellant mixture, the combustion region is observed to move up onto the afterbody of the projectile as the pressure field evolves to a distinctively different form that implies the presence of supersonic combustion processes. Eventually, a high enough Mach number is reached that the ram effect is sufficient to cause the combustion process to occur entirely on the body. Propulsive cycles utilizing on-body heat release can be established either by continuously accelerating the projectile in a single propellant mixture from low initial in-tube Mach numbers (M less than 4) or by injecting the projectile at a speed above the propellant's Chapman-Jouguet detonation speed. The results of experimental and theoretical explorations of ram accelerator gas dynamic phenomena and the effectiveness of the new diagnostic techniques are presented in this report.

Cyclic Explosivity in High Elevation Phreatomagmatic Eruptions at Ocean Island Volcanoes: Implications for Aquifer Pressurization and Volcano Flank Destabilization.

NASA Astrophysics Data System (ADS)

Tarff, R.; Day, S. J.; Downes, H.; Seghedi, I.

2015-12-01

Groundwater heating and pressurization of aquifers trapped between dikes in ocean island volcanoes has been proposed as a mechanism for destabilizing and triggering large-volume flank collapses. Previous modelling has indicated that heat transfer from sustained magma flow through dikes during eruption has the potential to produce destabilizing levels of pressure on time scales of 4 to 400 days, if the aquifers remain confined. Here we revisit this proposal from a different perspective. We examine evidence for pressure variations in dike-confined aquifers during eruptions at high elevation vents on ocean island volcanoes. Initially magmatic, these eruptions change to mostly small-volume explosive phreatomagmatic activity. A recent example is the 1949 eruption on La Palma, Canary Islands. Some such eruptions involve sequences of larger-volume explosive phases or cycles, including production of voluminous low-temperature, pyroclastic density currents (PDC). Here we present and interpret data from the Cova de Paul crater eruption (Santo Antao, Cape Verde Islands). The phreatomagmatic part of this eruption formed two cycles, each culminating with eruption of PDCs. Compositional and textural variations in the products of both cycles indicate that the diatreme fill began as coarse-grained and permeable which allowed gas to escape. During the eruption, the fill evolved to a finer grained, poorly sorted, less permeable material, in which pore fluid pressures built up to produce violent explosive phases. This implies that aquifers adjacent to the feeder intrusion were not simply depressurized at the onset of phreatomagmatic explosivity but experienced fluctuations in pressure throughout the eruption as the vent repeatedly choked and emptied. In combination with fluctuations in magma supply rate, driving of aquifer pressurization by cyclical vent choking will further complicate the prediction of flank destabilization during comparable eruptions on ocean island volcanoes.

Dynamical clustering of red blood cells in capillary vessels.

PubMed

Boryczko, Krzysztof; Dzwinel, Witold; Yuen, David A

2003-02-01

We have modeled the dynamics of a 3-D system consisting of red blood cells (RBCs), plasma and capillary walls using a discrete-particle approach. The blood cells and capillary walls are composed of a mesh of particles interacting with harmonic forces between nearest neighbors. We employ classical mechanics to mimic the elastic properties of RBCs with a biconcave disk composed of a mesh of spring-like particles. The fluid particle method allows for modeling the plasma as a particle ensemble, where each particle represents a collective unit of fluid, which is defined by its mass, moment of inertia, translational and angular momenta. Realistic behavior of blood cells is modeled by considering RBCs and plasma flowing through capillaries of various shapes. Three types of vessels are employed: a pipe with a choking point, a curved vessel and bifurcating capillaries. There is a strong tendency to produce RBC clusters in capillaries. The choking points and other irregularities in geometry influence both the flow and RBC shapes, considerably increasing the clotting effect. We also discuss other clotting factors coming from the physical properties of blood, such as the viscosity of the plasma and the elasticity of the RBCs. Modeling has been carried out with adequate resolution by using 1 to 10 million particles. Discrete particle simulations open a new pathway for modeling the dynamics of complex, viscoelastic fluids at the microscale, where both liquid and solid phases are treated with discrete particles. Figure A snapshot from fluid particle simulation of RBCs flowing along a curved capillary. The red color corresponds to the highest velocity. We can observe aggregation of RBCs at places with the most stagnant plasma flow.

Self-efficacy of first aid for home accidents among parents with 0- to 4-year-old children at a metropolitan community health center in Taiwan.

PubMed

Wei, Yu-Li; Chen, Li-Li; Li, Tsai-Chung; Ma, Wei-Fen; Peng, Niang-Huei; Huang, Li-Chi

2013-03-01

Although accidental injury is the main factor involved in the death of young children in many countries, few studies have focused on parents' competence with regard to self-efficacy of first aid for their children following injuries occurring at home. The purpose of this cross-sectional study was to investigate parental self-sufficiency of first aid for home accidents in children aged 0-4 years. The study is a cross-sectional designed. Data from 445 parents recruited were collected by purposive sampling at eight metropolitan community health centers in central Taiwan. Measurements were taken from a self-developed questionnaire that included 37 questions. Logistic regression analysis was applied to explore the associations between factors and parents' self-efficacy of first aid at home accident. Our findings show that parents' overall rate of knowledge of first aid was 72%. The mean score for 100% certainty in parents' self-efficacy of first aid was 26.6%. The lowest scores for self-efficacy were with regard to choking and cardiopulmonary resuscitation (CPR). There was a significantly positive correlation between parents' knowledge and self-efficacy of first aid (p<0.01), and thus knowledge of first aid is a predictor of parents' self-efficacy. Knowledge of first aid is also a partly mediator between participants' attending first aid program, participants' first aid information obtained from health personnel and self-efficacy of first aid. Our findings suggest that medical services should provide first aid resources to help manage accidental injuries involving children, particularly information on how to deal with choking and CPR. With an appropriate program provided by health professionals, parents' self-efficacy of first aid for home accidents will be positively enhanced. Copyright © 2013. Published by Elsevier Ltd.

Tracheobronchial Foreign Bodies in Children: The Role of Emergency Rigid Bronchoscopy

PubMed Central

Baram, Aram; Sherzad, Hewa; Saeed, Sara; Kakamad, Fahmi H.; Hamawandi, Adnan M. H.

2017-01-01

Foreign body aspiration (FBA) is a common and lethal accident in the pediatric age group. It requires early recognition and treatment by rigid bronchoscopy to avoid fatal outcomes. Objective. The aim of this study was to study the pattern of FBA in the tracheobronchial tree as well as the success rate of rigid bronchoscopy in children admitted to a single center and to analyze the relationship of the type of foreign body (FB) with patients’ age, presentation, and complications. Methods. A retrospective cross-sectional study of FBA was conducted in children in the Sulaimani/Kurdistan region, Iraq, admitted to the emergency teaching hospital of the University of Sulaimani from January 2014 to March 2016. Result. Data of 83 patients between 6 months and 15 years old were studied. The most affected was the 1- to 5-year-old group. There was a slight female predominance (male to female ratio 0.93:1). The most common FB was sunflower seed (49.4%). History of choking was present in 92.8% of patients; 55.4% had normal air entry, and 37.3% had no added sound on chest auscultation. Normal chest X-ray (CXR) was found in 40% of patients. The most common site was the right bronchial tree (39.8%). Two patients needed mechanical ventilation; both of them died. There was a significant relationship between the type of FB (P = .013, .000, respectively). Conclusion. Medical history is the most important factor for reaching the diagnosis; bronchoscopy is mandatory if choking was witnessed, even if examination and CXR are normal. Organic material causes more local reaction than nonorganic material. PMID:29226187

Antenna design for microwave hepatic ablation using an axisymmetric electromagnetic model

PubMed Central

Bertram, John M; Yang, Deshan; Converse, Mark C; Webster, John G; Mahvi, David M

2006-01-01

Background An axisymmetric finite element method (FEM) model was employed to demonstrate important techniques used in the design of antennas for hepatic microwave ablation (MWA). To effectively treat deep-seated hepatic tumors, these antennas should produce a highly localized specific absorption rate (SAR) pattern and be efficient radiators at approved generator frequencies. Methods and results As an example, a double slot choked antenna for hepatic MWA was designed and implemented using FEMLAB™ 3.0. Discussion This paper emphasizes the importance of factors that can affect simulation accuracy, which include boundary conditions, the dielectric properties of liver tissue, and mesh resolution. PMID:16504153

Atlantic multi-decadal oscillation covaries with Agulhas leakage

PubMed Central

Biastoch, Arne; Durgadoo, Jonathan V.; Morrison, Adele K.; van Sebille, Erik; Weijer, Wilbert; Griffies, Stephen M.

2015-01-01

The interoceanic transfer of seawater between the Indian Ocean and the Atlantic, ‘Agulhas leakage', forms a choke point for the overturning circulation in the global ocean. Here, by combining output from a series of high-resolution ocean and climate models with in situ and satellite observations, we construct a time series of Agulhas leakage for the period 1870–2014. The time series demonstrates the impact of Southern Hemisphere westerlies on decadal timescales. Agulhas leakage shows a correlation with the Atlantic Multi-decadal Oscillation on multi-decadal timescales; the former leading by 15 years. This is relevant for climate in the North Atlantic. PMID:26656850

A Study of Normal Shock-Wave Turbulent Boundary-Layer Interactions at Mach Numbers of 1.3, 1.4 and 1.5.

DTIC Science & Technology

1982-10-01

Veigas 13used a third technique which was to hold the normal shock wave steady in a supersonic tube by the adjustment of a conical choke downstream of...the equilibrium functioii E (equation (3) as tie eqoi ihri:’ fl -it I lows of East, Sawyer and Nash 2 8 . Although the maximum values of ti wakce :, i...f.. ..l.. .. .. ..t.. fl iC!alaCC CCCCCCCCt t CCCCCifllt CCCCCCCCit C C--- ---- -- C A CCC5C tCC C NC C - f CC1S $ C C A * E~ - - C 2

Limestone Creek, Local Flood Protection, Fayetteville, New York

DTIC Science & Technology

1990-08-01

maple, slippery elm , syca- more, black locust, dogwood, sumac, choke cherry, creeping cucumber, goldenrod and teasel. Wooded areas on the surrounding...CIRCLE C. -AkA- BARKER t LANE IVIALL KEN 4A AVE 2 7rflEE EEOER r ’A CHANIC S ENWOOD LANE Shcoping cc a ttev Center RNE -V ELM STREET GENES STREET...0~i r; 0 i cyO n 0 00.- w ~ 0vwf N - N 9 00 0 , - 00 -l N NO w IV a,0 200 000 -0 a, r. elm ID MW PN0NIN MOJn 0m M e. 0’iamo 0 q0 ON T0 Fw% N..NV

Martial arts sports medicine: current issues and competition event coverage.

PubMed

Nishime, Robert S

2007-06-01

More sports medicine professionals are becoming actively involved in the care of the martial arts athlete. Although there are many different forms of martial arts practiced worldwide, certain styles have shown a potential for increased participation in competitive-type events. Further research is needed to better understand the prevalence and profiles of injuries sustained in martial arts full-contact competitive events. Breaking down the martial art techniques into basic concepts of striking, grappling, and submission maneuvers, including choking and joint locking, may facilitate better understanding and management of injuries. This article outlines this approach and reviews the commonly encountered injuries and problems during martial arts full-contact competitions.

Atlantic multi-decadal oscillation covaries with Agulhas leakage

DOE PAGES

Biastoch, Arne; Durgadoo, Jonathan V.; Morrison, Adele K.; ...

2015-12-10

The interoceanic transfer of seawater between the Indian Ocean and the Atlantic, ‘Agulhas leakage’, forms a choke point for the overturning circulation in the global ocean. Here, by combining output from a series of high-resolution ocean and climate models with in situ and satellite observations, we construct a time series of Agulhas leakage for the period 1870–2014. The time series demonstrates the impact of Southern Hemisphere westerlies on decadal timescales. Agulhas leakage shows a correlation with the Atlantic Multi-decadal Oscillation on multi-decadal timescales; the former leading by 15 years. Lastly, this is relevant for climate in the North Atlantic.

Far Noise Field of Air Jets and Jet Engines

NASA Technical Reports Server (NTRS)

Callaghan, Edmund E; Coles, Willard D

1957-01-01

An experimental investigation was conducted to study and compare the acoustic radiation of air jets and jet engines. A number of different nozzle-exit shapes were studied with air jets to determine the effect of exit shape on noise generation. Circular, square, rectangular, and elliptical convergent nozzles and convergent-divergent and plug nozzles were investigated. The spectral distributions of the sound power for the engine and the air jet were in good agreement for the case where the engine data were not greatly affected by reflection or jet interference effects. Such power spectra for a subsonic or slightly choked engine or air jet show that the peaks of the spectra occur at a Strouhal number of 0.3.

Antithyroid drug-induced agranulocytosis complicated by pneumococcal sepsis and upper airway obstruction.

PubMed

Ishimaru, Naoto; Ohnishi, Hisashi; Nishiuma, Teruaki; Doukuni, Ryota; Umezawa, Kanoko; Oozone, Sachiko; Kuramoto, Emi; Yoshimura, Sho; Kinami, Saori

2013-01-01

Streptococcus pneumoniae is a rare pathogen of sepsis in patients with antithyroid drug-induced agranulocytosis. We herein describe a case of antithyroid drug-induced agranulocytosis complicated by pneumococcal sepsis and upper airway obstruction. A 27-year-old woman who was previously prescribed methimazole for nine months presented with a four-day history of a sore throat. She nearly choked and was diagnosed with febrile agranulocytosis. She was successfully treated with intubation, intravenous antibiotics and granulocyte colony-stimulating factor. Her blood cultures yielded S. pneumoniae. Emergency airway management, treatment of sepsis and the administration of granulocyte colony-stimulating factor can improve the clinical course of antithyroid drug-induced pneumococcal sepsis in patients with airway obstruction.

Method of analysis for compressible flow through mixed-flow centrifugal impellers of arbitrary design

NASA Technical Reports Server (NTRS)

Hamrick, Joseph T; Ginsburg, Ambrose; Osborn, Walter M

1952-01-01

A method is presented for analysis of the compressible flow between the hub and the shroud of mixed-flow impellers of arbitrary design. Axial symmetry was assumed, but the forces in the meridional (hub to shroud) plane, which are derived from tangential pressure gradients, were taken into account. The method was applied to an experimental mixed-flow impeller. The analysis of the flow in the meridional plane of the impeller showed that the rotational forces, the blade curvature, and the hub-shroud profile can introduce severe velocity gradients along the hub and the shroud surfaces. Choked flow at the impeller inlet as determined by the analysis was verified by experimental results.

Foreign body aspiration in adult airways: therapeutic approach

PubMed Central

Hewlett, Justin C.; Rickman, Otis B.; Lentz, Robert J.; Prakash, Udaya B.

2017-01-01

Tracheobronchial foreign body (FB) aspiration is an uncommon but potentially life-threatening event in adults. Symptoms typically consist of a choking event followed by cough and dyspnea, however, these findings are inconsistent and symptoms may mimic more chronic lung diseases such as asthma or chronic obstructive pulmonary disease. Chest radiography and computed tomography can provide information regarding the location and characteristics of foreign bodies and aid in diagnosis. Bronchoscopy remains the gold standard for diagnosis and management of FB aspiration. The authors describe the typical clinical presentation, diagnostic evaluation, and bronchoscopic management of foreign bodies in adult airways with a focus on bronchoscopic techniques and potential complications of FB extraction. PMID:29221325

Aerodynamic and acoustic performance of high Mach number inlets

NASA Technical Reports Server (NTRS)

Lumsdaine, E.; Clark, L. R.; Cherng, J. C.; Tag, I.

1977-01-01

Experimental results were obtained for two types of high Mach number inlets, one with a translating centerbody and one with a fixed geometry (collapsing cowl) without centerbody. The aerodynamic and acoustic performance of these inlets was examined. The effects of several parameters such as area ratio and length-diameter ratio were investigated. The translating centerbody inlet was found to be superior to the collapsing cowl inlet both acoustically and aerodynamically, particularly for area ratios greater than 1.5. Comparison of length-diameter ratio and area ratio effects on performance near choked flow showed the latter parameter to be more significant. Also, greater high frequency noise attenuation was achieved by increasing Mach number from low to high subsonic values.

Mach 6 experimental and theoretical stability and performance of a cruciform missile at angles of attack up to 65 degrees

NASA Technical Reports Server (NTRS)

Hartman, Edward R.; Johnston, Patrick J.

1987-01-01

An experimental and theoretical investigation of the longitudinal and lateral-directional stability and control of an axisymmetric cruciform-finned missile has been conducted at Mach 6. The angle-of-attack range extended from 20 to 65 deg to encompass maximum lift. Longitudinal stability, performance, and trim could be accurately predicted with the fins at a fin roll angle of 0 deg but not when the fins were at a fin roll angle of 45 deg. At this roll angle, windward fin choking occurred at angles of attack above 50 deg and reduced the effectiveness of the fins and caused pitch-up.

Pressure recovery performance of conical diffusers at high subsonic Mach numbers

NASA Technical Reports Server (NTRS)

Dolan, F. X.; Runstadler, P. W., Jr.

1973-01-01

The pressure recovery performance of conical diffusers has been measured for a wide range of geometries and inlet flow conditions. The approximate level and location (in terms of diffuser geometry of optimum performance were determined. Throat Mach numbers from low subsonic (m sub t equals 0.2) through choking (m sub t equals 1.0) were investigated in combination with throat blockage from 0.03 to 0.12. For fixed Mach number, performance was measured over a fourfold range of inlet Reynolds number. Maps of pressure recovery are presented as a function of diffuser geometry for fixed sets of inlet conditions. The influence of inlet blockage, throat Mach number, and inlet Reynolds number is discussed.

Induction simulation of gas core nuclear engine

NASA Technical Reports Server (NTRS)

Poole, J. W.; Vogel, C. E.

1973-01-01

The design, construction and operation of an induction heated plasma device known as a combined principles simulator is discussed. This device incorporates the major design features of the gas core nuclear rocket engine such as solid feed, propellant seeding, propellant injection through the walls, and a transpiration cooled, choked flow nozzle. Both argon and nitrogen were used as propellant simulating material, and sodium was used for fuel simulating material. In addition, a number of experiments were conducted utilizing depleted uranium as the fuel. The test program revealed that satisfactory operation of this device can be accomplished over a range of operating conditions and provided additional data to confirm the validity of the gas core concept.

The prevalence and impact of intimate partner violence on maternal distress in a community of low-income Bangladeshi and displaced ethnic Bihari mothers: Dhaka, 2008-2009.

PubMed

Azziz-Baumgartner, Eduardo; Homaira, Nusrat; Hamadani, J D; Tofail, Fahmida; Dahlberg, Linda L; Haque, Rashidul; Luby, Stephen P; Naved, Ruchira T

2014-01-01

Low-income, ethnic, and/or displaced mothers are frequently victimized; we explored the burden of intimate partner violence (IPV) among such women. Teams administered IPV and maternal distress questionnaires to quantify victimization after the birth of a child. Of 250 mothers reporting abuse, 133 (53%) reported their husband hitting; 111 (44%) kicking, dragging, or beating; 61 (24%) choking or burning; and 33 (13%) injuring them with a knife or gun (12 case-patients per 100 person-years). Women who experienced more forms of victimization reported more distress (p = .01). Mothers in this low-income community experienced severe victimization and distress.

Feeding ecology of arctic-nesting sandpipers during spring migration through the prairie pothole region

USGS Publications Warehouse

Eldridge, J.L.; Krapu, G.L.; Johnson, D.H.

2009-01-01

We evaluated food habits of 4 species of spring-migrant calidrid sandpipers in the Prairie Pothole Region (PPR) of North Dakota. Sandpipers foraged in several wetland classes and fed primarily on aquatic dipterans, mostly larvae, and the midge family Chironomidae was the primary food eaten. Larger sandpiper species foraged in deeper water and took larger larvae than did smaller sandpipers. The diverse wetland habitats that migrant shorebirds use in the PPR suggest a landscape-level approach be applied to wetland conservation efforts. We recommend that managers use livestock grazing and other tools, where applicable, to keep shallow, freshwater wetlands from becoming choked with emergent vegetation limiting chironomid production and preventing shorebird use.

A static investigation of several STOVL exhaust system concepts

NASA Technical Reports Server (NTRS)

Romine, B. M., Jr.; Meyer, B. E.; Re, R. J.

1989-01-01

A static cold flow scale model test was performed in order to determine the internal performance characteristics of various STOVL exhaust systems. All of the concepts considered included a vectorable cruise nozzle and a separate vectorable vertical thrust ventral nozzle mounted on the tailpipe. The two ventral nozzle configurations tested featured vectorable constant thickness cascade vanes for area control and improved performance during transition and vertical lift flight. The best transition performance was achieved using a butterfly door type ventral nozzle and a pitch vectoring 2DCD or axisymmetric cruise nozzle. The clamshell blocker type of ventral nozzle had reduced transition performance due to the choking of the tailpipe flow upstream of the cruise nozzle.

Noise generated by flow through large butterfly valves

NASA Technical Reports Server (NTRS)

Huff, Ronald G.

1987-01-01

A large butterfly valve (1.37 m diam) was acoustically tested to measure the noise generated and propagating in both the upstream and downstream directions. The experimental investigation used wall mounted pressure transducers to measure the fluctuating component of the pipe static pressure upstream and downstream of the valve. Microphones upstream of the pipe inlet and located in a plenum were used to measure the noise radiated from the valve in the upstream direction. Comparison of the wall pressure downstream of the valve to a prediction were made. Reasonable agreement was obtained with the valve operating at a choked condition. The noise upstream of the valve is 30 dB less than that measured downstream.

Volcano Hazards - A National Threat

USGS Publications Warehouse

,

2006-01-01

When the violent energy of a volcano is unleashed, the results are often catastrophic. The risks to life, property, and infrastructure from volcanoes are escalating as more and more people live, work, play, and travel in volcanic regions. Since 1980, 45 eruptions and 15 cases of notable volcanic unrest have occurred at 33 U.S. volcanoes. Lava flows, debris avalanches, and explosive blasts have invaded communities, swept people to their deaths, choked major riverways, destroyed bridges, and devastated huge tracts of forest. Noxious volcanic gas emissions have caused widespread lung problems. Airborne ash clouds have disrupted the health, lives, and businesses of hundreds of thousands of people; caused millions of dollars of aircraft damage; and nearly brought down passenger flights.

Modifications to the nozzle test chamber to extend nozzle static-test capability

NASA Technical Reports Server (NTRS)

Keyes, J. W.

1985-01-01

The nozzle test chamber was modified to provide a high-pressure-ratio nozzle static-test capability. Experiments were conducted to determine the range of the ratio of nozzle total pressure to chamber pressure and to make direct nozzle thrust measurements using a three-component strain-gage force balance. Pressure ratios from 3 to 285 were measured with several axisymmetric nozzles at a nozzle total pressure of 15 to 190 psia. Devices for measuring system mass flow were calibrated using standard axisymmetric convergent choked nozzles. System mass-flow rates up to 10 lbm/sec are measured. The measured thrust results of these nozzles are in good agreement with one-dimensional theoretical predictions for convergent nozzles.

[Inside the apothecary... what drugs...the contents of civilian pharmacies in lower Normandy and Canada in the eighteenth century].

PubMed

Tésio, Stéphanie

2010-01-01

The post-mortem inventories, true notarised documents, are choked full with details on the way of life of XVIIIth century apothecares. The most interesting of them describe exactly for us the content of apothecaries: drugs, remedies, pots, etc. starting from the examples of two representative regions of metropolitan France and its colonies, linked by a history of immigration that is Low-Normandy, which sent a number of its people to North America, and Canada. We will examine apothecaries' material possessions and the tolls of their daily trade. One primordial question emerges: the influence of Amerindian medicine on French and French-Canada XVIIIth century pharmacy.

Analysis of the dynamic response of a supersonic inlet to flow-field perturbations upstream of the normal shock

NASA Technical Reports Server (NTRS)

Cole, G. L.; Willoh, R. G.

1975-01-01

A linearized mathematical analysis is presented for determining the response of normal shock position and subsonic duct pressures to flow-field perturbations upstream of the normal shock in mixed-compression supersonic inlets. The inlet duct cross-sectional area variation is approximated by constant-area sections; this approximation results in one-dimensional wave equations. A movable normal shock separates the supersonic and subsonic flow regions, and a choked exit is assumed for the inlet exit condition. The analysis leads to a closed-form matrix solution for the shock position and pressure transfer functions. Analytical frequency response results are compared with experimental data and a method of characteristics solution.

Digital-computer normal shock position and restart control of a Mach 2.5 axisymmetric mixed-compression inlet

NASA Technical Reports Server (NTRS)

Neiner, G. H.; Cole, G. L.; Arpasi, D. J.

1972-01-01

Digital computer control of a mixed-compression inlet is discussed. The inlet was terminated with a choked orifice at the compressor face station to dynamically simulate a turbojet engine. Inlet diffuser exit airflow disturbances were used. A digital version of a previously tested analog control system was used for both normal shock and restart control. Digital computer algorithms were derived using z-transform and finite difference methods. Using a sample rate of 1000 samples per second, the digital normal shock and restart controls essentially duplicated the inlet analog computer control results. At a sample rate of 100 samples per second, the control system performed adequately but was less stable.

Presenting symptoms of giant fibrovascular polyp of the oesophagus: case report and literature review.

PubMed

Sestini, S; Gisabella, M; Pastorino, U; Billé, A

2016-05-01

Lipomas of the gastrointestinal tract are rare, slow-growing lesions that comprise 0.4% of all gastrointestinal neoplasms. They can cause dysphagia, dyspnoea or sudden choking. Due to rarity of this condition and its uncommon presentation, a literature review was carried out (PubMed). This search revealed 290 articles, of which 74 were considered pertinent and were evaluated. We report a case of a 13cm pedunculated oesophageal lipoma that presented with increasing dysphagia and two episodes of suffocation. The patient underwent curative resection through a cervical approach. Resection is recommended for large (>5 cm) or symptomatic polyps. Outcomes are excellent given that lesions are universally benign and oesophageal resection is not required.

Multifunctional Inflatable Structure Being Developed for the PowerSphere Concept

NASA Technical Reports Server (NTRS)

Peterson, Todd T.

2003-01-01

The continuing development of microsatellites and nanosatellites for low Earth orbits requires the collection of sufficient power for instruments onboard a low-weight, low-volume spacecraft. Because the overall surface area of a microsatellite or nanosatellite is small, body-mounted solar cells cannot provide enough power. The deployment of traditional, rigid, solar arrays necessitates larger satellite volumes and weights, and also requires extra apparatus for pointing. One solution to this power choke problem is the deployment of a spherical, inflatable power system. This power system, termed the "PowerSphere," has several advantages, including a high collection area, low weight and stowage volume, and the elimination of solar array pointing mechanisms.

Freeze-drying simulation framework coupling product attributes and equipment capability: toward accelerating process by equipment modifications.

PubMed

Ganguly, Arnab; Alexeenko, Alina A; Schultz, Steven G; Kim, Sherry G

2013-10-01

A physics-based model for the sublimation-transport-condensation processes occurring in pharmaceutical freeze-drying by coupling product attributes and equipment capabilities into a unified simulation framework is presented. The system-level model is used to determine the effect of operating conditions such as shelf temperature, chamber pressure, and the load size on occurrence of choking for a production-scale dryer. Several data sets corresponding to production-scale runs with a load from 120 to 485 L have been compared with simulations. A subset of data is used for calibration, whereas another data set corresponding to a load of 150 L is used for model validation. The model predictions for both the onset and extent of choking as well as for the measured product temperature agree well with the production-scale measurements. Additionally, we study the effect of resistance to vapor transport presented by the duct with a valve and a baffle in the production-scale freeze-dryer. Computation Fluid Dynamics (CFD) techniques augmented with a system-level unsteady heat and mass transfer model allow to predict dynamic process conditions taking into consideration specific dryer design. CFD modeling of flow structure in the duct presented here for a production-scale freeze-dryer quantifies the benefit of reducing the obstruction to the flow through several design modifications. It is found that the use of a combined valve-baffle system can increase vapor flow rate by a factor of 2.2. Moreover, minor design changes such as moving the baffle downstream by about 10 cm can increase the flow rate by 54%. The proposed design changes can increase drying rates, improve efficiency, and reduce cycle times due to fewer obstructions in the vapor flow path. The comprehensive simulation framework combining the system-level model and the detailed CFD computations can provide a process analytical tool for more efficient and robust freeze-drying of bio-pharmaceuticals. Copyright © 2013 Elsevier B.V. All rights reserved.

Can a bronchoscopist reliably assess a patient's experience of bronchoscopy?

PubMed Central

Hadzri, HM; Azarisman, SMS; Fauzi, ARM; Roslan, H; Roslina, AM; Adina, ATN; Fauzi, MA

2010-01-01

Objectives Bronchoscopy is an essential investigative tool in many respiratory complaints. The procedure can be unpleasant for both bronchoscopists and patients. To the best of our knowledge, there are only a few studies that correlate the bronchoscopist's satisfaction with that of the patient's during bronchoscopy. The aim of our study is to assess whether or not a bronchoscopist could reliably assess a patient's satisfaction during bronchoscopy. Design Cross-sectional, observational study with convenience sampling. Setting Patients attending flexible fibreoptic bronchoscopy appointments at the bronchoscopy suite, Respiratory Unit, Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Cheras, Kuala Lumpur, Malaysia between March and September 2006. Participants Sixty patients undergoing bronchoscopy over a 6-month period completed a questionnaire after the procedure. All patients received standard pre-medication with intravenous midazolam. Main outcome measures Bronchoscopists and patients rated the level of satisfaction of the procedure using a 10 cm visual analogue scale (VAS). Lower scores indicated better satisfaction or less discomfort. Patients and bronchoscopists also rated coughing, choking and vomiting perception using the same 10 cm VAS. Reliability analysis (intra-class correlation coefficient [ICC]) was used to analyse the correlation between patients' and bronchoscopists' VAS scores. Results All 60 patients answered the questionnaire. The median overall satisfaction scored by bronchoscopists was 2.2 (2.0) with a non-significant (p = 0.880) trend to a better median overall satisfaction of 1.9 (2.3) scored by patients. The VAS scores for cough sensation were 1.9 (2.7) and 1.5 (5.0), respectively. There was positive correlation between bronchoscopists' and patients' VAS scores for coughing sensation (p = 0.047, ICC = 0.233). No significant correlation for overall satisfaction, vomiting sensation and choking sensation was found. Conclusion Positive correlation for cough perception suggested that the bronchoscopist could reliably assess the degree of cough discomfort patients experience during bronchoscopy. PMID:21103127

Analysis of Unsteady Tip and Endwall Heat Transfer in a Highly Loaded Transonic Turbine Stage

NASA Technical Reports Server (NTRS)

Shyam, Vikram; Ameri, Ali; Chen, Jen-Ping

2010-01-01

In a previous study, vane-rotor shock interactions and heat transfer on the rotor blade of a highly loaded transonic turbine stage were simulated. The geometry consists of a high pressure turbine vane and downstream rotor blade. This study focuses on the physics of flow and heat transfer in the rotor tip, casing and hub regions. The simulation was performed using the Unsteady Reynolds-Averaged Navier-Stokes (URANS) code MSU-TURBO. A low Reynolds number k-epsilon model was utilized to model turbulence. The rotor blade in question has a tip gap height of 2.1 percent of the blade height. The Reynolds number of the flow is approximately 3x10(exp 6) per meter. Unsteadiness was observed at the tip surface that results in intermittent "hot spots". It is demonstrated that unsteadiness in the tip gap is governed by inviscid effects due to high speed flow and is not strongly dependent on pressure ratio across the tip gap contrary to published observations that have primarily dealt with subsonic tip flows. The high relative Mach numbers in the tip gap lead to a choking of the leakage flow that translates to a relative attenuation of losses at higher loading. The efficacy of new tip geometry is discussed to minimize heat flux at the tip while maintaining choked conditions. In addition, an explanation is provided that shows the mechanism behind the rise in stagnation temperature on the casing to values above the absolute total temperature at the inlet. It is concluded that even in steady mode, work transfer to the near tip fluid occurs due to relative shearing by the casing. This is believed to be the first such explanation of the work transfer phenomenon in the open literature. The difference in pattern between steady and time-averaged heat flux at the hub is also explained.

Diagnosis and Management of Oropharyngeal Dysphagia Among Older Persons, State of the Art.

PubMed

Ortega, Omar; Martín, Alberto; Clavé, Pere

2017-07-01

Oropharyngeal dysphagia (OD) is a condition recognized by the World Health Organization and defined as the difficulty or inability to move a bolus safely and effectively from the oral cavity to the esophagus, and can include aspirations, choking, and residue. OD is pandemic among different phenotypes of older people, affecting between 27% and 91% of the population 70 years or older. Although OD can be diagnosed by well-defined clinical methods and complementary explorations, in the clinical setting OD is seldom systematically screened and treated, and awareness among the medical/geriatric community is scarce. The etiology of OD in this population includes many concomitant risk factors with neurogenic and neurodegenerative processes, muscular weakness, and sarcopenia. The pathophysiology includes mechanical deficits in the swallow response (mainly delayed laryngeal vestibule closure time and weak tongue thrust), reduced pharyngeal sensitivity, and sensory/motor central nervous system impairments. Recently, OD has been recognized as a geriatric syndrome due to its high prevalence and its relationship with many comorbidities and their poor outcomes, including malnutrition, respiratory infections and aspiration pneumonia, functional disability and frailty, institutionalization and increased readmissions, and mortality. There is an evidence-based and effective treatment for OD in the elderly mainly oriented to compensating swallow impairments through adaptation of fluid viscosity and solid food textures to avoid aspiration and choking, and improving nutritional status and oral health to avoid respiratory infections. This has been defined as the minimal effective treatment to be provided to this population. New treatments aiming at recovering the swallowing function are under research with promising results, and the near future will provide us with methods to stimulate the swallow response with pharmacological or physical stimuli. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Building Climate Resilience in the Blue Nile/Abay Highlands: A Framework for Action

PubMed Central

Simane, Belay; Zaitchik, Benjamin F.; Mesfin, Desalegn

2012-01-01

Ethiopia has become warmer over the past century and human induced climate change will bring further warming over the next century at unprecedented rates. On the average, climate models show a tendency for higher mean annual rainfall and for wetter conditions, in particular during October, November and December, but there is much uncertainty about the future amount, distribution, timing and intensity of rainfall. Ethiopia’s low level of economic development, combined with its heavy dependence on agriculture and high population growth rate make the country particularly susceptible to the adverse effects of climate change. Nearly 90% of Ethiopia’s population lives in the Highlands, which include the critical Blue Nile (Abay) Highlands—a region that holds special importance due to its role in domestic agricultural production and international water resources. A five year study of climate vulnerability and adaptation strategies in communities of Choke Mountain, located in the center of the Abay Highlands, has informed a proposed framework for enhancing climate resilience in communities across the region. The framework is motivated by the critical need to enhance capacity to cope with climate change and, subsequently, to advance a carbon neutral and climate resilient economy in Ethiopia. The implicit hypothesis in applying a research framework for this effort is that science-based information, generated through improved understanding of impacts and vulnerabilities of local communities, can contribute to enhanced resilience strategies. We view adaptation to climate change in a wider context of changes, including, among others, market conditions, the political-institutional framework, and population dynamics. From a livelihood perspective, culture, historical settings, the diversity of income generation strategies, knowledge, and education are important factors that contribute to adaptive capacities. This paper reviews key findings of the Choke Mountain study, describes the principles of the climate resilience framework, and proposes an implementation strategy for climate resilient development to be applied in the Abay Highlands, with potential expansion to agricultural communities across the region and beyond. PMID:22470313

Resolving key drivers of variability through an important circulation choke point in the western Mediterranean Sea; using gliders, models & satellite remote sensing

NASA Astrophysics Data System (ADS)

Heslop, Emma; Aguiar, Eva; Mourre, Baptiste; Juza, Mélanie; Escudier, Romain; Tintoré, Joaquín

2017-04-01

The Ibiza Channel plays an important role in the circulation of the Western Mediterranean Sea, it governs the north/south exchange of different water masses that are known to affect regional ecosystems and is influenced by variability in the different drivers that affect sub-basins to the north (N) and south (S). A complex system. In this study we use a multi-platform approach to resolve the key drivers of this variability, and gain insight into the inter-connection between the N and S of the Western Mediterranean Sea through this choke point. The 6-year glider time series from the quasi-continuous glider endurance line monitoring of the Ibiza Channel, undertaken by SOCIB (Balearic Coastal Ocean observing and Forecasting System), is used as the base from which to identify key sub-seasonal to inter-annual patterns and shifts in water mass properties and transport volumes. The glider data indicates the following key components in the variability of the N/S flow of different water mass through the channel; regional winter mode water production, change in intermediate water mass properties, northward flows of a fresher water mass and the basin-scale circulation. To resolve the drivers of these components of variability, the strength of combining datasets from different sources, glider, modeling, altimetry and moorings, is harnessed. To the north atmospheric forcing in the Gulf of Lions is a dominant driver, while to the south the mesoscale circulation patterns of the Atlantic Jet and Alboran gyres dominate the variability but do not appear to influence the fresher inflows. Evidence of a connection between the northern and southern sub-basins is however indicated. The study highlights importance of sub-seasonal variability and the scale of rapid change possible in the Mediterranean, as well as the benefits of leveraging high resolution glider datasets within a multi-platform and modelling study.

Component Performance Investigation of J71 Type II Turbines: III - Overall Performance of J71 Type IIA Turbine

NASA Technical Reports Server (NTRS)

Schum, Harold J.; Davison, Elmer H.; Petrash, Donald A.

1955-01-01

The over-all component performance characteristics of the J71 Type IIA three-stage turbine were experimentally determined over a range of speed and over-all turbine total-pressure ratio at inlet-air conditions af 35 inches of mercury absolute and 700 deg. R. The results are compared with those obtained for the J71 Type IIF turbine, which was previously investigated, the two turbines being designed for the same engine application. Geometrically the two turbines were much alike, having the same variation of annular flow area and the same number of blades for corresponding stator and rotor rows. However, the blade throat areas downstream of the first stator of the IIA turbine were smaller than those of the IIF; and the IIA blade profiles were curve-backed, whereas those of the IIF were straight-backed. The IIA turbine passed the equivalent design weight flow and had a brake internal efficiency of 0.880 at design equivalent speed and work output. A maximum efficiency of 0.896 occurred at 130 percent of design equivalent speed and a pressure ratio of 4.0. The turbine had a wide range of efficient operation. The IIA turbine had slightly higher efficiencies than the IIF turbine at comparable operating conditions. The fact that the IIA turbine obtained the design equivalent weight flow at the design equivalent operating point was probably a result of the decrease in the blading throat areas downstream of the first stator from those of the IIF turbine, which passed 105 percent of design weight flow at the corresponding operating point. The third stator row of blades of the IIA turbine choked at the design equivalent speed and at an over-all pressure ratio of 4.2; the third rotor choked at a pressure ratio of approximately 4.9

Hydrodynamic Restoration to Vulnerable Marsh Ecosystems to Improve Response to Sea Level Rise

NASA Astrophysics Data System (ADS)

Orescanin, M. M.; Hamilton, R. P., Jr.

2016-12-01

Rising sea levels pose imminent threats to low-lying marsh ecosystems owing to delicate balances between water levels, salinity, and sediment transport. Further complications arise from human modifications to these low-lying coastal areas that modify topography, thus altering tidal exchanges. The Milford Neck Conservation Area, near Milford, DE, is a salt marsh system on Delaware Bay that has undergone morphological modifications owing to both human activity and natural processes resulting in damage to the surrounding marsh habitats. A century-old abandoned canal acted as a physical barrier to any tidal exchange for upland marsh for decades, allowing land at low elevations to be dry and used for agricultural activities. However, a breach to the system in the 1980s created a link to Delaware Bay that flooded salt hay fields, creating a large area of open water. Owing to tidal restrictions in the system, it has been difficult to transport sufficient sediment and water into the system to promote natural marsh growth. At the same time, the eroding barrier beach increases vulnerability to sea level rise and storms of increasing severity and frequency, and places upland forest at risk of episodic salt intrusion. To increase the effectiveness of this area as a barrier to sea level rise, it is necessary to increase marsh resiliency. Hydrodynamic measurements collected during fall 2015 and spring/summer 2016 show tidal choking in the system that limits exchange of salt water from Delaware Bay and prevents drainage from storm runoff. Numerical model results using the hydrodynamic model, CMS-flow, confirm tidal choking in this system and suggest localized areas are responsible for the most significant reduction in tidal exchange between the marsh and Delaware Bay. Analysis of hypsometry of the area combined with potential for improving tidal flushing suggest the possibility of restoring close to 400 acres of open water and damaged marsh.

[Correlation of snoring with attention deficit and hyperactivity-impulsivity in school age children from Changsha City].

PubMed

Li, Jie-Min; Hu, Jin-Tao; Luo, Xue-Mei; Cai, Yi-Min; Liu, Jie-Ming

2009-07-01

To investigate the prevalence of snoring in school age children from Changsha City, and study the correlation of snoring with attention deficit and hyperactivity-impulsivity. A total of 1 736 children aged 6 to 12 years were randomly sampled from five districts in Changsha City. Their parents completed the questionnaires about children's sleep conditions and the Attention Deficit Hyperactivity Disorder Diagnostic Scale-Parent Version. The total incidence rate of frequent snoring was 5.7%. Boys had higher incidence of frequent snoring than girls (7.5% vs 3.8%; x2=18.782, p<0.01). The incidence of snoring in the 6-to 9-year-old group was higher than that of the 10-to 12-year-old group (x2=9.666, P<0.01). The incidence of daytime sleepiness in the snoring group was higher than that in the non-snoring group (31.5% vs 25.9%; x2=6.678, p<0.01). The incidences of larynx choking, sleep apnea, mouth breathing, hyperhidrosis, and awaking for unknown reasons or awaking by choke in the frequent snoring group were significantly higher than in the occasional snoring and the non-snoring groups (x2=37.035, 27.745, 51.341, 30.975, 45.972 respectively; all P<0.01). The incidences of attention deficit (31.3%) and hyperactivity-impulsivity (18.2%) in the frequent snoring group were the highest, followed by the occasional snoring (16.2% and 9.9% respectively) and the non-snoring groups (13.9% and 8.8% respectively). There were significant differences in the incidence of both attention deficit (x2=20.592, p<0.01) and hyperactivity-impulsivity (x2=9.067, p<0.05) between groups. There is a high incidence of snoring in school age children from Changsha City. Snoring is correlated to attention deficit and hyperactivity-impulsivity. It is essential to pay attention to the mental growth and behavioral problems in children with sleep snoring.

A cocoon shock breakout as the origin of the γ-ray emission in GW170817

NASA Astrophysics Data System (ADS)

Gottlieb, Ore; Nakar, Ehud; Piran, Tsvi; Hotokezaka, Kenta

2018-06-01

The short Gamma-Ray Burst, GRB170817A, that followed the binary neutron star merger gravitational waves signal, GW170817, is not a usual sGRB. It is weaker by three orders of magnitude than the weakest sGRB seen before and its spectra, showing a hard early signal followed by a softer thermal spectrum, is unique. We show, first, that the γ-rays must have emerged from at least mildly relativistic outflow, implying that a relativistic jet was launched following the merger. We then show that the observations are consistent with the predictions of a mildly relativistic shock breakout: a minute γ-ray energy as compared with the total energy and a rather smooth light curve with a hard to soft evolution. We present here a novel analytic study and detailed numerical 2D and 3D relativistic hydrodynamic and radiation simulations that support the picture in which the observed γ-rays arose from a shock breakout of a cocoon from the merger's ejecta (Kasliwal et al. 2017). The cocoon can be formed by either a choked jet which does not generate a sGRB (in any direction) or by a successful jet which generates an undetected regular sGRB along the system's axis pointing away from us. Remarkably, for the choked jet model, the macronova signal produced by the ejecta (which is partially boosted to high velocities by the cocoon's shock) and the radio that is produced by the interaction of the shocked cocoon material with the surrounding matter, agree with the observed UV/optical/IR emission and with current radio observations. Finally, we discuss the possibility that the jet propagation within the ejecta may photodissociate some of of the heavy elements and may affect the composition of a fraction of ejecta and, in turn, the opacity and the early macronova light.

[Association between two different types of strangling and intraocular pressure variation in jiu-jitsu athletes].

PubMed

Scarpi, Marinho Jorge; Conte, Marcelo; Rossin, Reginaldo Alexandre; Skubs, Renato; Lenk, Rudolf Eberhard; Brant, Rodrigo

2009-01-01

To verify the association between two different types of strangling with intraocular pressure variation in jiu-jitsu athletes. An observational study was performed on 9 athletes of jiu-jitsu, with at least 6 month of training, male, aged 20 to 30 years, without any physical and eyeball lesions. Associations between intraocular pressure and Cross Choke from the guard strangling (E1), and E2 - Cross Choke from mount strangling were gotten. Intraocular pressure was determined by using Perkins tonometer, at first in the absence of physical exercise over the last 24 hours and after each strangling. Then it was carried out the intraocular pressure measure at each 3 minutes, during 12 minutes of exercise recovery (R1, R2, R3, and R4) keeping the athletes lied down. Statistical analysis was done using ANOVA test and Bonferroni post-test. Meaningful reduction of both eyes intraocular pressure occurred at the E2 situation comparing to the E1 situation at all exercise recovery measures: R1 (OD: 8.22 +/- 1.39 vs.11.33 +/- 2.00 / OE: 8.55 +/- 1.23 vs. 11.88 +/- 1.90), R2 (OD: 8.44 +/- 1.87 vs.10.22 +/- 2.53 / OE: 9.00 +/- 1.80 vs. 10.44 +/- 2.35), R3 (OD: 8.44 +/- 1.74 vs.9.78 +/- 2.54 / OE: 8.55 +/- 1.42 vs. 10.33 +/- 1.93) all with p<0,01 e R4 (OD: 8.88 +/- 2.08 vs.9.55 +/- 2.87 / OE: 9.11 +/- 1.53 vs. 10.44 +/- 2.18) with p<0.05. Meaningful IOP reduction (p<0.05) was observed at the R1 moment of E2 strangling (OD: 10.77 +/- 1.92 vs.8.22 +/- 1.39 / OE: 11.44 +/- 1.94 vs. 8.55 +/- 1.23). There is association between intraocular pressure and jiu-jitsu strangling exercises, with intraocular pressure reduction.

Preliminary findings on the effects of geometry on two-phase flow through volcanic conduits

NASA Astrophysics Data System (ADS)

Mitchell, K. L.; Wilson, L.; Lane, S. J.; James, M. R.

2003-04-01

We attempt to ascertain whether some of the geometrical assumptions utilised in modelling of flows through volcanic conduits are valid. Flow is often assumed to be through a vertical conduit, but some volcanoes, such as Pu'u 'O'o (Kilauea, Hawai'i) and Stromboli (Italy), are known to exhibit inclined or more complex conduit systems. Our numerical and experimental studies have revealed that conduit inclination is a first-order influence on flow properties and eruptive style. Even a few degrees of inclination from vertical can increase gas-liquid phase separation by locally enhancing the gas volume fraction on the upper surface of the conduit. We explore the consequences of phase separation and slug flow for styles of magmatic eruption, and consider how these apply to particular eruptions. Modellers also tend to assume a simple parallel-sided geometry for volcanic conduits. Some have used a pressure-balanced assumption allowing conduits to choke and flare, resulting in higher eruption velocities. The pressure-balanced assumption is flawed in that it does not deal with the effects of compressibility and associated shocks when the flow is supersonic. Both parallel-sided and pressure-balanced assumptions avoid addressing how conduit shape evolves from an initial dyke-shaped fracture. However, we assert that evolution of conduit shape is impossible to quantify accurately using a deterministic approach. Therefore we adopt a simplified approach, with the initial conduit shape as a blade-shaped dyke, and the potential end-member as a system that is pressure-balanced up to the supersonic choking point and undetermined beyond (flow is constrained by a narrow jet envelope and not by the walls). Intermediate geometries are assumed to change quasi-steadily at locations where conduit wall stresses are high, and the consequences of these geometries are explored. We find that quite small changes in conduit geometry, which are likely to occur in volcanic systems, can have a significant effect on flow speeds.

Measurement of groove features and dimensions of the vertical test cathode and the choke joint of the superconducting electron gun cavity of the Energy Recovery LINAC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hammons, L.; Ke, M.

2011-10-13

A testing program for the superconducting electron gun cavity that has been designed for the Energy Recovery LINAC is being planned. The goal of the testing program is to characterize the RF properties of the gun cavity at superconducting temperatures and, in particular, to study multipacting that is suspected to be occurring in the choke joint of the cavity where the vertical test cathode is inserted. The testing program will seek to understand the nature and cause of this multipacting and attempt to eliminate it, if possible, by supplying sufficient voltage to the cavity. These efforts are motivated by themore » multipacting issues that have been observed in the processing of the fine-grain niobium gun cavity. This cavity, which is being processed at Thomas Jefferson National Laboratory for Brookhaven, has encountered multipacting at a gradient of approximately 3 MV/m and, to date, has resisted efforts at elimination. Because of this problem, a testing program is being established here in C-AD that will use the large-grain niobium gun cavity that currently resides at Brookhaven and has been used for room-temperature measurements. The large-grain and fine-cavities are identical in every aspect of construction and only differ in niobium grain size. Thus, it is believed that testing and conditioning of the large-grain cavity should yield important insights about the fine-grain cavity. One element of this testing program involves characterizing the physical features of the choke joint of the cavity where the multipacting is believed to be occurring and, in particular the grooves of the joint. The configuration of the cavity and the vertical test cathode is shown in Figure 1. In addition, it is important to characterize the groove of the vertical test cathode. The grooved nature of these two components was specifically designed to prevent multipacting. However, it is suspected that, because of the chemical processing that the fine-grain gun cavity underwent along with the vertical test cathode, the geometry of these grooves was altered, presenting the possibility that multipacting may, in fact, be occurring in this area and contributing to the low gradients that have been observed in the fine-grain cavity. Therefore, the Survey and Alignment group in C-AD engaged in measurements of the cavity joint, shown in Figure 2 and the cathode weldment, shown in Figure 3 for the purpose of characterizing the grooves in both the cavity and the vertical test cathode and comparing the dimensions of the cathode with those of the prints supplied by Advanced Energy Systems (AES), the original designer and manufacturer of both the test cathode and the electron gun cavity, in preparation to have a new one manufactured. The goal was to ensure that the articles as built matched the design prints in preparation for manufacturing a new vertical test cathode. This report describes the data collected by the Survey group in these efforts. The endeavor was challenging for the group given the millimeter-scale dimensions of the grooves and the requirement for high precision.« less

Wall interference in a two-dimensional-flow wind tunnel, with consideration of the effect of compressibility

NASA Technical Reports Server (NTRS)

Allen, H Julian; Vincenti, Walter G

1944-01-01

Theoretical tunnel-wall corrections are derived for an airfoil of finite thickness and camber in a two-dimensional-flow wind tunnel. The theory takes account of the effects of the wake of the airfoil and of the compressibility of the fluid, and is based upon the assumption that the chord of the airfoil is small in comparison with the height of the tunnel. Consideration is given to the phenomenon of choking at high speeds and its relation to the tunnel-wall corrections. The theoretical results are compared with the small amount of low-speed experimental data available and the agreement is seen to be satisfactory, even for relatively large values of the chord-height ratio.

Theoretical considerations for Reaction-Formed Silicon Carbide (RFSC) formation by molten silicon infiltration into slurry-derived preforms

NASA Technical Reports Server (NTRS)

Behrendt, D. R.; Singh, M.

1993-01-01

For reaction-formed silicon carbide (RFSC) ceramics produced by silicon melt infiltration of porous carbon preforms, equations are developed to relate the amount of residual silicon to the initial carbon density. Also, for a slurry derived preform containing both carbon and silicon powder, equations are derived which relate the amount of residual silicon in the RFSC to the relative density of the carbon in the preform and to the amount of silicon powder added to the slurry. For a porous carbon preform that does not have enough porosity to prevent choking-off of the silicon infiltration, these results show that complete silicon infiltration can occur by adding silicon powder to the slurry mixture used to produce these preforms.

Gas turbine engine

DOEpatents

Lawlor, Shawn P.; Roberts, II, William Byron

2016-03-08

A gas turbine engine with a compressor rotor having compressor impulse blades that delivers gas at supersonic conditions to a stator. The stator includes a one or more aerodynamic ducts that each have a converging portion and a diverging portion for deceleration of the selected gas to subsonic conditions and to deliver a high pressure oxidant containing gas to flameholders. The flameholders may be provided as trapped vortex combustors, for combustion of a fuel to produce hot pressurized combustion gases. The hot pressurized combustion gases are choked before passing out of an aerodynamic duct to a turbine. Work is recovered in a turbine by expanding the combustion gases through impulse blades. By balancing the axial loading on compressor impulse blades and turbine impulse blades, asymmetrical thrust is minimized or avoided.

Ice-sheet response to oceanic forcing.

PubMed

Joughin, Ian; Alley, Richard B; Holland, David M

2012-11-30

The ice sheets of Greenland and Antarctica are losing ice at accelerating rates, much of which is a response to oceanic forcing, especially of the floating ice shelves. Recent observations establish a clear correspondence between the increased delivery of oceanic heat to the ice-sheet margin and increased ice loss. In Antarctica, most of these processes are reasonably well understood but have not been rigorously quantified. In Greenland, an understanding of the processes by which warmer ocean temperatures drive the observed retreat remains elusive. Experiments designed to identify the relevant processes are confounded by the logistical difficulties of instrumenting ice-choked fjords with actively calving glaciers. For both ice sheets, multiple challenges remain before the fully coupled ice-ocean-atmosphere models needed for rigorous sea-level projection are available.

Measurement of Gust Response on a Turbine Cascade

NASA Technical Reports Server (NTRS)

Kurkov, A. P.; Lucci, B. L.

1995-01-01

The paper presents benchmark experimental data on a gust response of an annular turbine cascade. The experiment was particularly designed to provide data for comparison with the results of a typical linearized gust-response analysis. Reduced frequency, Mach number, and incidence were varied independently. Except for the lowest reduced frequency, the gust velocity distribution was nearly sinusoidal. For the high inlet-velocity series of tests, the cascade was near choking. The mean flow was documented by measuring blade surface pressures and the cascade exit flow. High-response pressure transducers were used to measure the unsteady pressure distribution. Inlet-velocity components and turbulence parameters were measured using hot wire. In addition to the synchronous time-average pressure spectra, typical power spectra are included for several representative conditions.

Natural gas hydrates and the mystery of the Bermuda Triangle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gruy, H.J.

1998-03-01

Natural gas hydrates occur on the ocean floor in such great volumes that they contain twice as much carbon as all known coal, oil and conventional natural gas deposits. Releases of this gas caused by sediment slides and other natural causes have resulted in huge slugs of gas saturated water with density too low to float a ship, and enough localized atmospheric contamination to choke air aspirated aircraft engines. The unexplained disappearances of ships and aircraft along with their crews and passengers in the Bermuda Triangle may be tied to the natural venting of gas hydrates. The paper describes whatmore » gas hydrates are, their formation and release, and their possible link to the mystery of the Bermuda Triangle.« less

Pediatric feeding and swallowing rehabilitation: An overview.

PubMed

van den Engel-Hoek, Lenie; Harding, Celia; van Gerven, Marjo; Cockerill, Helen

2017-05-16

Children with neurological disabilities frequently have problems with feeding and swallowing. Such problems have a significant impact on the health and well-being of these children and their families. The primary aims in the rehabilitation of pediatric feeding and swallowing disorders are focused on supporting growth, nutrition and hydration, the development of feeding activities, and ensuring safe swallowing with the aim of preventing choking and aspiration pneumonia. Pediatric feeding and swallowing disorders can be divided into four groups: transient, developmental, chronic or progressive.This article provides an overview of the available literature about the rehabilitation of feeding and swallowing disorders in infants and children. Principles of motor control, motor learning and neuroplasticity are discussed for the four groups of children with feeding and swallowing disorders.

Unsteady Flow Simulation of a Sweeping Jet Actuator Using a Lattice-Boltzmann Method

NASA Technical Reports Server (NTRS)

Duda, B.; Wessels, M.; Fares, E.; Vatsa, V.

2016-01-01

Active flow control technology is increasingly used in aerospace applications to control flow separation and to improve aerodynamic performance. In this paper, PowerFLOW is used to simulate the flow through a sweeping jet actuator at two different pressure ratios. The lower pressure ratio leads to a high subsonic flow, whereas the high pressure ratio produces a choked flow condition. Comparison of numerical results with experimental data is shown, which includes qualitatively good agreement of pressure histories and spectra. PIV measurements are also available but the simulation overestimates mean and fluctuation quantities outside the actuator. If supply pressure is matched at one point inside the mixing chamber a good qualitative agreement is achieved at all other monitor points.

Risky Behaviors and Social Networking Sites: How Is YouTube Influencing Our Youth?

PubMed

Ahern, Nancy R; Sauer, Penny; Thacker, Paige

2015-10-01

Choking, cutting, and setting oneself on fire are just a few of the risky behaviors that the YouTube video sharing website has allowed youth around the world to view, emulate, and comment on. Some researchers contend that the viewing of videos may normalize these behaviors for youth. Disturbing current trends are explored to illustrate the darker side of YouTube. Psychiatric-mental health nurses (PMHNs) are in key positions to help parents and youth better understand the benefits and risks of social networking sites, including YouTube, and to encourage healthy and safe use of the Internet. Nursing implications are offered for PMHNs, educators, health care providers, and parents who have contact with this population. Copyright 2015, SLACK Incorporated.

Experiments on H2-O2MHD power generation

NASA Technical Reports Server (NTRS)

Smith, J. M.

1980-01-01

Magnetohydrodynamic power generation experiments utilizing a cesium-seeded H2-O2 working fluid were carried out using a diverging area Hall duct having an entrance Mach number of 2. The experiments were conducted in a high-field strength cryomagnet facility at field strengths up to 5 tesla. The effects of power takeoff location, axial duct location within the magnetic field, generator loading, B-field strength, and electrode breakdown voltage were investigated. For the operating conditions of these experiments, it is found that the power output increases with the square of the B-field and can be limited by choking of the channel or interelectrode voltage breakdown which occurs at Hall fields greater than 50 volts/insulator. Peak power densities of greater than 100 MW/cu M were achieved.

Analogy between fluid cavitation and fracture mechanics

NASA Astrophysics Data System (ADS)

Hendricks, R. C.; Mullen, R. L.; Braun, M. J.

When the stresses imposed on a fluid are sufficiently large, rupture or cavitation can occur. Such conditions can exist in many two-phase flow applications, such as the choked flows, which can occur in seals and bearings. Nonspherical bubbles with large aspect ratios have been observed in fluids under rapid acceleration and high shear fields. These bubbles are geometrically similar to fracture surface patterns (Griffith crack model) existing in solids. Analogies between crack growth in solid and fluid cavitation are proposed and supported by analysis and observation (photographs). Healing phenomena (void condensation), well accepted in fluid mechanics, have been observed in some polymers and hypothesized in solid mechanics. By drawing on the strengths of the theories of solid mechanics and cavitation, a more complete unified theory can be developed.

Biosorption of heavy metals and uranium from dilute solutions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schneider, I.A.H.; Misra, M.; Smith, R.W.

1995-08-01

Eichhornia crassipes approaches being a scourge in many parts of the world, choking waterways and hindering transport upon them. At the same time it is known to readily abstract heavy metal ions from water and, thus, aids in the removal of heavy metals found in such waters. This paper considers the possibility of using specific parts of the plant as an inexpensive adsorbent for the removal of heavy metals from contaminated chemical and mining industry waste waters. In particular the root of the plant was found to be an excellent accumulator of heavy metal ions including uranium from solution. Itmore » is also suggested that dried roots of the plant might be placed in simple bags and used in a very low cost metal ion removal system.« less

Production enhancement through aggressive flowback procedures in the Codell formation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, A.J.; Ashton, P.J.N.; Lang, J.

1996-12-31

Proppant flowback following fracture stimulation treatments continues to be a major concern in many wells around the world. The current trend towards more tip screen out (TSO) and reverse screenout designs has increased the need for better control of proppant flowback under increasingly severe drag force conditions. Recent studies in the Codell formation have indicated a correlation between load water and polymer recovery on fracture cleanup and subsequent gas production. This paper describes a subsequent twenty-five well study of the specific effects of combining forced closure/reverse gravel packs along with varying flowback rates and choke schedules on load water recoverymore » and normalized gas and condensate production. One of the key issues addressed is the use of aggressive flowback schedules while maintaining proppant flowback control.« less

Interaction of reflected ions with the firehose marginally stable current sheet - Implications for plasma sheet convection

NASA Technical Reports Server (NTRS)

Pritchett, P. L.; Coroniti, F. V.

1992-01-01

The firehose marginally stable current sheet, which may model the flow away from the distant reconnection neutral line, assumes that the accelerated particles escape and never return to re-encounter the current region. This assumption fails on the earthward side where the accelerated ions mirror in the geomagnetic dipole field and return to the current sheet at distances up to about 30 R(E) down the tail. Two-dimensional particle simulations are used to demonstrate that the reflected ions drive a 'shock-like' structure in which the incoming flow is decelerated and the Bz field is highly compressed. These effects are similar to those produced by adiabatic choking of steady convection. Possible implications of this interaction for the dynamics of the tail are considered.

Poppet valve control of throat stability bypass to increase stable airflow range of a Mach 2.5. inlet with 60 percent internal contraction

NASA Technical Reports Server (NTRS)

Mitchell, G. A.; Sanders, B. W.

1975-01-01

The throat of a Mach 2.5 inlet with a coldpipe termination was fitted with a stability-bypass system. System variations included several stability bypass entrance configurations. Poppet valves controlled the bypass airflow. The inlet stable airflow range achieved with each configuration was determined for both steady state conditions and internal pulse transients. Results are compared with those obtained without a stability bypass system. Transient results were also obtained for the inlet with a choke point at the diffuser exit and for the inlet with large and small stability bypass plenum volumes. Poppet valves at the stability bypass exit provided the inlet with a stable airflow range of 20 percent or greater at all static and transient conditions.

Pressure activated stability-bypass-control valves to increase the stable airflow range of a Mach 2.5 inlet with 40 percent internal contraction

NASA Technical Reports Server (NTRS)

Mitchell, G. A.; Sanders, B. W.

1974-01-01

The throat of a Mach 2.5 inlet with a coldpipe termination was fitted with a stability-bypass system. The inlet stable airflow range provided by various stability-bypass entrance configurations in alternate combination with several stability-bypass exit controls was determined for both steady-state conditions and internal transient pulses. Transient results were also obtained for the inlet with a choke point at the diffuser exit. Instart angles of attack were determined for the various stability-bypass entrance configurations. The response of the inlet-coldpipe system to internal and external oscillating disturbances was determined. Poppet valves at the stability-bypass exit provided an inlet stable airflow range of 28 percent or greater at all static and transient conditions.

Analogy between fluid cavitation and fracture mechanics

NASA Technical Reports Server (NTRS)

Hendricks, R. C.; Mullen, R. L.; Braun, M. J.

1983-01-01

When the stresses imposed on a fluid are sufficiently large, rupture or cavitation can occur. Such conditions can exist in many two-phase flow applications, such as the choked flows, which can occur in seals and bearings. Nonspherical bubbles with large aspect ratios have been observed in fluids under rapid acceleration and high shear fields. These bubbles are geometrically similar to fracture surface patterns (Griffith crack model) existing in solids. Analogies between crack growth in solid and fluid cavitation are proposed and supported by analysis and observation (photographs). Healing phenomena (void condensation), well accepted in fluid mechanics, have been observed in some polymers and hypothesized in solid mechanics. By drawing on the strengths of the theories of solid mechanics and cavitation, a more complete unified theory can be developed.

Oral function and nutritional status among the elderly with facial and oral tactile hypersensitivity who are under long-term care.

PubMed

Shirobe, Maki; Nakayama, Rena; Hirano, Hirohiko; Ohara, Yuki; Endo, Keiko; Watanabe, Yutaka; Hakuta, Chiyoko

2017-01-01

Objective　In oral health care, a refusal action can cause difficulties, and tactile hypersensitivity (TH) may be a contributing factor. People with TH of the face and mouth clench their jaws. Despite numerous reports on TH among children with disabilities, reports on TH in the elderly who are under long-term care are scarce. The purpose of this study was to investigate TH among the elderly who are under long-term care.Methods　We selected 80 residents (8 men and 72 women; mean age: 91.1±6.2y) in a Tokyo nursing home and investigated the presence of TH in them. We also obtained patients' (1) basic information (sex, age, stage of long-term care needs (SCN), and the degree of independent living (IL)); (2) oral information (swallowing status, choking tendency, and intraoral residue); and (3) nutritional information (serum albumin (Alb) levels and body mass index (BMI)). We assessed the face (the forehead, cheek, and perioral area) and the intraoral environment (buccal mucosa, buccal cavity, and palate) as testing sites for TH, using the tester's palm and forefinger. We confirmed the presence of TH when the tested areas reacted partially or fully by shuddering. We classified the subjects into 2 groups based on the presence or absence of TH and analyzed our results using a chi-square test and Mann-Whitney U test. This investigation was approved by the Dentistry Ethics Screening Committee, Tokyo Medical and Dental University.Results　A total of 18 residents were diagnosed with TH (22.5%). Significant differences in SCN, IL, choking tendency, intraoral residue, swallowing status, serum Alb levels, and BMI (P<0.05) were reported between this group and the non-TH group.Conclusion　We demonstrated that residents with TH were in an advanced SCN and had a lower IL score and a decreased swallowing and nutritional status. Therefore, oral health care, promotion of nutritional status, and meal support are particularly important for the elderly with TH.

Stability analysis for capillary channel flow: 1d and 3d computations

NASA Astrophysics Data System (ADS)

Grah, Aleksander; Klatte, Jörg; Dreyer, Michael E.

The subject of the presentation are numerical studies on capillary channel flow, based on results of the sounding rocket TEXUS experiments. The flow through a capillary channel is established by a gear pump at the outlet. The channel, consists of two parallel glass plates with a width of 25 mm, a gap of 10 mm and a length of 12 mm. The meniscus of a compensation tube maintains a constant system pressure. Steady and dynamic pressure effects in the system force the surfaces to bend inwards. A maximum flow rate is achieved when the free surface collapses and gas ingestion occurs at the outlet. This critical flow rate depends on the channel geometry, the flow regime and the liquid properties. The aim of the experiments is the determination of the free surface shape and to find the maximum flow rate. In order to study the unsteady liquid loop behavior, a dimensionless one-dimensional model and a corresponding three-dimensional model were developed. The one-dimensional model is based on the unsteady Bernoulli equation, the unsteady continuity equation and geometrical conditions for the surface curvature and the flow cross-section. The experimental and evaluated contour data show good agreement for a sequence of transient flow rate perturbations. In the case of steady flow at maximum flow rate, when the "choking" effect occurs, the surfaces collapse and cause gas ingestion into the channel. This effect is related to the Speed Index. At the critical flow rate the Speed Index reaches the value 1, in analogy to the Mach Number. Unsteady choking does not necessarily cause surface collapse. We show, that temporarily Speed Index values exceeding One may be achieved for a perfectly stable supercritical dynamic flow. As a supercritical criterion for the dynamic free surface stability we define a Dynamic Index considering the local capillary pressure and the convective pressure, which is a function of the local velocity. The Dynamic Index is below One for stable flow while D = 1 indicates surface collapse. This studies lead to a stability diagram, which defines the limits of flow dynamics and the maximum unsteady flow rate.

Ion mobility spectrometric analysis of vaporous chemical warfare agents by the instrument with corona discharge ionization ammonia dopant ambient temperature operation.

PubMed

Satoh, Takafumi; Kishi, Shintaro; Nagashima, Hisayuki; Tachikawa, Masumi; Kanamori-Kataoka, Mieko; Nakagawa, Takao; Kitagawa, Nobuyoshi; Tokita, Kenichi; Yamamoto, Soichiro; Seto, Yasuo

2015-03-20

The ion mobility behavior of nineteen chemical warfare agents (7 nerve gases, 5 blister agents, 2 lachrymators, 2 blood agents, 3 choking agents) and related compounds including simulants (8 agents) and organic solvents (39) was comparably investigated by the ion mobility spectrometry instrument utilizing weak electric field linear drift tube with corona discharge ionization, ammonia doping, purified inner air drift flow circulation operated at ambient temperature and pressure. Three alkyl methylphosphonofluoridates, tabun, and four organophosphorus simulants gave the intense characteristic positive monomer-derived ion peaks and small dimer-derived ion peaks, and the later ion peaks were increased with the vapor concentrations. VX, RVX and tabun gave both characteristic positive monomer-derived ions and degradation product ions. Nitrogen mustards gave the intense characteristic positive ion peaks, and in addition distinctive negative ion peak appeared from HN3. Mustard gas, lewisite 1, o-chlorobenzylidenemalononitrile and 2-mercaptoethanol gave the characteristic negative ion peaks. Methylphosphonyl difluoride, 2-chloroacetophenone and 1,4-thioxane gave the characteristic ion peaks both in the positive and negative ion mode. 2-Chloroethylethylsulfide and allylisothiocyanate gave weak ion peaks. The marker ion peaks derived from two blood agents and three choking agents were very close to the reactant ion peak in negative ion mode and the respective reduced ion mobility was fluctuated. The reduced ion mobility of the CWA monomer-derived peaks were positively correlated with molecular masses among structurally similar agents such as G-type nerve gases and organophosphorus simulants; V-type nerve gases and nitrogen mustards. The slope values of the calibration plots of the peak heights of the characteristic marker ions versus the vapor concentrations are related to the detection sensitivity, and within chemical warfare agents examined the slope values for sarin, soman, tabun and nitrogen mustards were higher. Some CWA simulants and organic solvents gave the ion peaks eluting at the similar positions of the CWAs, resulting in false positive alarms. Copyright © 2015 Elsevier B.V. All rights reserved.

Simulation of Unique Pressure Changing Steps and Situations in Psa Processes

NASA Technical Reports Server (NTRS)

Ebner, Armin D.; Mehrotra, Amal; Knox, James C.; LeVan, Douglas; Ritter, James A.

2007-01-01

A more rigorous cyclic adsorption process simulator is being developed for use in the development and understanding of new and existing PSA processes. Unique features of this new version of the simulator that Ritter and co-workers have been developing for the past decade or so include: multiple absorbent layers in each bed, pressure drop in the column, valves for entering and exiting flows and predicting real-time pressurization and depressurization rates, ability to account for choked flow conditions, ability to pressurize and depressurize simultaneously from both ends of the columns, ability to equalize between multiple pairs of columns, ability to equalize simultaneously from both ends of pairs of columns, and ability to handle very large pressure ratios and hence velocities associated with deep vacuum systems. These changes to the simulator now provide for unique opportunities to study the effects of novel pressure changing steps and extreme process conditions on the performance of virtually any commercial or developmental PSA process. This presentation will provide an overview of the cyclic adsorption process simulator equations and algorithms used in the new adaptation. It will focus primarily on the novel pressure changing steps and their effects on the performance of a PSA system that epitomizes the extremes of PSA process design and operation. This PSA process is a sorbent-based atmosphere revitalization (SBAR) system that NASA is developing for new manned exploration vehicles. This SBAR system consists of a 2-bed 3-step 3-layer system that operates between atmospheric pressure and the vacuum of space, evacuates from both ends of the column simultaneously, experiences choked flow conditions during pressure changing steps, and experiences a continuously changing feed composition, as it removes metabolic CO2 and H20 from a closed and fixed volume, i.e., the spacecraft cabin. Important process performance indicators of this SBAR system are size, and the corresponding CO2 and H20 removal efficiencies, and N2 and O2 loss rates. Results of the fundamental behavior of this PSA process during extreme operating conditions will be presented and discussed.

Energy Saving Melting and Revert Reduction Technology (Energy-SMARRT): Clean Steel Casting Production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuyucak, Selcuk; Li, Delin

2013-12-31

Inclusions in steel castings can cause rework, scrap, poor machining, and reduced casting performance, which can obviously result in excess energy consumption. Significant progress in understanding inclusion source, formation and control has been made. Inclusions can be defined as non-metallic materials such as refractory, sand, slag, or coatings, embedded in a metallic matrix. This research project has focused on the mold filling aspects to examine the effects of pouring methods and gating designs on the steel casting cleanliness through water modeling, computer modeling, and melting/casting experiments. Early in the research project, comprehensive studies of bottom-pouring water modeling and low-alloy steelmore » casting experiments were completed. The extent of air entrainment in bottom-poured large castings was demonstrated by water modeling. Current gating systems are designed to prevent air aspiration. However, air entrainment is equally harmful and no prevention measures are in current practice. In this study, new basin designs included a basin dam, submerged nozzle, and nozzle extension. The entrained air and inclusions from the gating system were significantly reduced using the new basin method. Near the end of the project, there has been close collaboration with Wescast Industries Inc., a company manufacturing automotive exhaust components. Both computer modeling using Magma software and melting/casting experiments on thin wall turbo-housing stainless steel castings were completed in this short period of time. Six gating designs were created, including the current gating on the pattern, non-pressurized, partially pressurized, naturally pressurized, naturally pressurized without filter, and radial choke gating without filter, for Magma modeling. The melt filling velocity and temperature were determined from the modeling. Based on the simulation results, three gating designs were chosen for further melting and casting experiments on the same casting pattern using the lip pouring method. It was observed again that gating designs greatly influenced the melt filling velocity and the number of inclusion defects. The radial choked gating showed improvements in casting cleanliness and yield over the other gatings, even though no mold filters were used in the gating system.« less

Hemangiopericytoma in the lateral ventricle.

PubMed

Suzuki, Sakiko; Wanifuchi, Hiroshi; Shimizu, Takashi; Kubo, Osami

2009-11-01

A 31-year-old female presented with a particularly rare hemangiopericytoma (HPC) in the right lateral ventricle manifesting as a 6-month history of visual disturbance and headache. Left hemianopsia and choked disc were identified by an ophthalmologist who referred her to us. Magnetic resonance imaging demonstrated a 5-cm homogeneously enhanced mass in the trigone of the right lateral ventricle. The tumor was totally removed by two stage surgery. The histological findings were consistent with HPC. HPC is very important to differentiate from meningioma and solitary fibrous tumors because HPC is more aggressive. The histological and immunochemical findings are important for the differential diagnosis. The present case showed no local recurrence or metastasis without radiation therapy for 4 years, indicating that radiation therapy is not absolutely imperative for patients with intraventricular HPC showing low MIB-1 staining index after total removal.

Comparative oceanography of coastal lagoons

NASA Technical Reports Server (NTRS)

Kjerfve, Bjorn

1986-01-01

The hypothesis that physical lagoon characteristics and variability depend on the channel connecting the lagoon to the adjacent coastal ocean is evaluated. The geographical, hydrological, and oceanographic characteristics of 10 lagoon systems are described and analyzed; these oceanographic features are utilized to classify the lagoon systems. Choked lagoons (Laguna Joyuda, Coorong, Lake St.Lucia, Gippsland Lakes, Lake Songkla/Thale Luang/Thale Noi, and Lagoa dos Patos) are prevalent on coasts with high wave energy and low tidal range; restricted lagoons (Lake Pontchartrain and Laguna de Terminos) are located on low/medium wave energy coasts with a low tidal range; and leaky lagoons (Mississippi Sound and Belize Lagoon/Chetumal Bay) are connected to the ocean by wide tidal passes that transmit oceanic effects into the lagoon with a minimum of resistance. The data support the hypothesis that the nature of the connecting channel controls system functions.

Some observations of the effects of radial distortions on performance of a transonic rotating blade row

NASA Technical Reports Server (NTRS)

Sandercock, D. M.; Sanger, N. L.

1974-01-01

A single rotating blade row was tested with two magnitudes of tip radial distortion and two magnitudes of hub radial distortion imposed on the inlet flow. The rotor was about 50 centimeters (20 in.) in diameter and had a design operating tip speed of approximately 420 meters per second (1380 ft/sec). Overall performance at 60, 80, and 100 percent of equivalent design speed generally showed a decrease (compared to undistorted flow) in rotor stall margin with tip radial distortion but no change, or a slight increase, in rotor stall margin with hub radial distortion. At design speed there was a decrease in rotor overall total pressure ratio and choke flow with all inlet flow distortions. Radial distributions of blade element parameters are presented for selected operating conditions at design speed.

Simulation of Non-Newtonian Emulsion Flows in Microchannels

NASA Astrophysics Data System (ADS)

Malanichev, I. V.; Akhmadiev, F. G.

2015-11-01

Simulation of emulsion flows in differently shaped microchannels to reproduce the choking of such flows as a result of the effect of dynamic blocking has been made. A model of a highly concentrated emulsion as a structure of tightly packed deformed droplets surrounded by elastic shells is considered. The motion of liquid was determined by the method of the lattice Boltzmann equations together with the immersed boundary method. The influence of the non-Newtonian properties and of elastic turbulence of the indicated emulsion, as well as of the elasticity of the shells of its droplets and of the interaction of these shells on the emulsion motion in a microchannel, has been investigated. It is shown that the flow of this emulsion can be slowed down substantially only due to the mutual attraction of the shells of its droplets.

Why you need a mentor

NASA Astrophysics Data System (ADS)

Riendeau, Diane

2014-10-01

At the AAPT Summer Meeting in Minneapolis, I co-hosted the speed networking event with Sam Sampere (the current NY section representative). Before the event began, I met with Sam briefly to discuss how we anticipated the event running. One of the first things Sam did was show me a memorial flyer from John Fitzgibbons' (Fitz) funeral. Sam later became choked up as he shared with the group about how his mentor, Fitz, had changed his life professionally at Syracuse and as a member of the AAPT. Sam suggested to the new attendees that perhaps their mentor was in the room and they would meet him or her today. All "seasoned" teachers in the room were nodding their heads in agreement. They could relate because there was someone who nurtured them, someone who deserves half the credit for the people and teachers they became.

Ocean plankton. Environmental characteristics of Agulhas rings affect interocean plankton transport.

PubMed

Villar, Emilie; Farrant, Gregory K; Follows, Michael; Garczarek, Laurence; Speich, Sabrina; Audic, Stéphane; Bittner, Lucie; Blanke, Bruno; Brum, Jennifer R; Brunet, Christophe; Casotti, Raffaella; Chase, Alison; Dolan, John R; d'Ortenzio, Fabrizio; Gattuso, Jean-Pierre; Grima, Nicolas; Guidi, Lionel; Hill, Christopher N; Jahn, Oliver; Jamet, Jean-Louis; Le Goff, Hervé; Lepoivre, Cyrille; Malviya, Shruti; Pelletier, Eric; Romagnan, Jean-Baptiste; Roux, Simon; Santini, Sébastien; Scalco, Eleonora; Schwenck, Sarah M; Tanaka, Atsuko; Testor, Pierre; Vannier, Thomas; Vincent, Flora; Zingone, Adriana; Dimier, Céline; Picheral, Marc; Searson, Sarah; Kandels-Lewis, Stefanie; Acinas, Silvia G; Bork, Peer; Boss, Emmanuel; de Vargas, Colomban; Gorsky, Gabriel; Ogata, Hiroyuki; Pesant, Stéphane; Sullivan, Matthew B; Sunagawa, Shinichi; Wincker, Patrick; Karsenti, Eric; Bowler, Chris; Not, Fabrice; Hingamp, Pascal; Iudicone, Daniele

2015-05-22

Agulhas rings provide the principal route for ocean waters to circulate from the Indo-Pacific to the Atlantic basin. Their influence on global ocean circulation is well known, but their role in plankton transport is largely unexplored. We show that, although the coarse taxonomic structure of plankton communities is continuous across the Agulhas choke point, South Atlantic plankton diversity is altered compared with Indian Ocean source populations. Modeling and in situ sampling of a young Agulhas ring indicate that strong vertical mixing drives complex nitrogen cycling, shaping community metabolism and biogeochemical signatures as the ring and associated plankton transit westward. The peculiar local environment inside Agulhas rings may provide a selective mechanism contributing to the limited dispersal of Indian Ocean plankton populations into the Atlantic. Copyright © 2015, American Association for the Advancement of Science.

A hierarchy for modeling high speed propulsion systems

NASA Technical Reports Server (NTRS)

Hartley, Tom T.; Deabreu, Alex

1991-01-01

General research efforts on reduced order propulsion models for control systems design are overviewed. Methods for modeling high speed propulsion systems are discussed including internal flow propulsion systems that do not contain rotating machinery such as inlets, ramjets, and scramjets. The discussion is separated into four sections: (1) computational fluid dynamics model for the entire nonlinear system or high order nonlinear models; (2) high order linearized model derived from fundamental physics; (3) low order linear models obtained from other high order models; and (4) low order nonlinear models. Included are special considerations on any relevant control system designs. The methods discussed are for the quasi-one dimensional Euler equations of gasdynamic flow. The essential nonlinear features represented are large amplitude nonlinear waves, moving normal shocks, hammershocks, subsonic combustion via heat addition, temperature dependent gases, detonation, and thermal choking.

The effect of intermediate clothing targets on shotgun ballistics.

PubMed

Cail, Kenneth; Klatt, Edward

2013-12-01

The ballistic properties of shotgun shells are complex because of multiple projectiles fired simultaneously that interact and spread out to affect their energy relayed to a human target. Intermediate targets such as clothing can affect penetration into tissues. We studied the effect of common clothing fabrics as intermediate targets on penetration of shotgun shell pellets, using ordnance gelatin to simulate soft tissue and thin cowhide to simulate skin. A standard 12-gauge shotgun with modified choke was used with no. 8 shot ammunition. We found that protection afforded by fabrics to reduce penetration of shotgun pellets into tissues was greater at increasing distance from the muzzle beyond 40 yd (36.6 m). The thicker denim and cotton fabrics provided slightly greater protection than polyester. This study demonstrates that clothing modifies the potential wound patterns to victims of shotgun injuries.

Microwave switching power divider. [antenna feeds

NASA Technical Reports Server (NTRS)

Stockton, R. J.; Johnson, R. W. (Inventor)

1981-01-01

A pair of parallel, spaced-apart circular ground planes define a microwave cavity with multi-port microwave power distributing switching circuitry formed on opposite sides of a thin circular dielectric substrate disposed between the ground planes. The power distributing circuitry includes a conductive disk located at the center of the substrate and connected to a source of microwave energy. A high speed, low insertion loss switching diode and a dc blocking capacitor are connected in series between the outer end of a transmission line and an output port. A high impedance, microwave blocking dc bias choke is connected between each switching diode and a source of switching current. The switching source forward biases the diodes to couple microwave energy from the conductive disk to selected output ports and, to associated antenna elements connected to the output ports to form a synthesized antenna pattern.

Mass spectrometric measurements of driver gas arrival in the T4 free-piston shock-tunnel

NASA Astrophysics Data System (ADS)

Boyce, R. R.; Takahashi, M.; Stalker, R. J.

2005-12-01

Available test time is an important issue for ground-based flow research, particularly for impulse facilities such as shock tunnels, where test times of the order of several ms are typical. The early contamination of the test flow by the driver gas in such tunnels restricts the test time. This paper reports measurements of the driver gas arrival time in the test section of the T4 free-piston shock-tunnel over the total enthalpy range 3 17 MJ/kg, using a time-of-flight mass spectrometer. The results confirm measurements made by previous investigators using a choked duct driver gas detector at these conditions, and extend the range of previous mass spectrometer measurements to that of 3 20 MJ/kg. Comparisons of the contamination behaviour of various piston-driven reflected shock tunnels are also made.

Solving gas-processing problems. Part 8. Expansion processes, turboexpander efficiency vital for predicting liquid-recovery levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erbar, J.H.; Maddox, R.N.

1981-07-06

Expansion processes, using either Joule-Thomson or isentropic principles play an important role in the processing of natural gas streams for liquid recovery and/or hydrocarbon-dewpoint control. Constant-enthalpy expansion has been an integral part of gas processing schemes for many years. The constant entropy, or isentropic, process is more recent but has achieved wide-spread popularity. In typcial flow sheets for expansion processess, the expansion device is shown to be a value or choke. It also could be an expansion turbine to indicate an isentropic expansion. The expansion may be to lower pressure; or, in the case of turboexpansion, it could recover materialmore » or produce work. More frequently, the aim of the expansion is to produce low temperature and enhance liquid recovery.« less

Harmonic uniflow engine

DOEpatents

Bennett, Charles L.

2016-03-22

A reciprocating-piston uniflow engine includes a harmonic oscillator inlet valve capable of oscillating at a resonant frequency for controlling the flow of working fluid into the engine. In particular, the inlet valve includes an inlet valve head and a spring arranged together as a harmonic oscillator so that the inlet valve head is moveable from an unbiased equilibrium position to a biased closed position occluding an inlet. When released, the inlet valve head undergoes a single oscillation past the equilibrium position to a maximum open position and returns to a biased return position close to the closed position to choke the flow and produce a pressure drop across the inlet valve causing the inlet valve to close. In other embodiments, the harmonic oscillator arrangement of the inlet valve enables the uniflow engine to be reversibly operated as a uniflow compressor.

"Music & Memory" and improved swallowing in advanced dementia.

PubMed

Cohen, Dan; Post, Stephen G; Lo, Angela; Lombardo, Robin; Pfeffer, Brandon

2018-01-01

Background Dysphagia and difficulty with eating affects a significant portion of individuals with advanced dementia. Such problems with oral intake can have serious health consequences including mealtime distress, dehydration and malnutrition, aspiration, reduced quality of life, and increased mortality risk. Design We present the first data indicating that "Music & Memory" interventions improve swallowing in individuals with advanced dementia, thereby making oral feeding easier and potentially diminishing reliance on PEG. Setting Columbia Health Care Center, Wyocena, WI (with Music&Memory.org, Mineola, NY and Stony Brook University). Participants Residents with advanced dementia (N = 5). Observation by eight professional caregivers. Results (1) Enhanced swallowing mechanism with Music & Memory prior to dining; (2) decreased incidents of choking during mealtime; (3) improved nutritional status; (4) reduced weight loss; (5) reduced need for speech interventions; (6) enhanced quality of life. Conclusions The preliminary results call for additional research.

Camelid genomes reveal evolution and adaptation to desert environments.

PubMed

Wu, Huiguang; Guang, Xuanmin; Al-Fageeh, Mohamed B; Cao, Junwei; Pan, Shengkai; Zhou, Huanmin; Zhang, Li; Abutarboush, Mohammed H; Xing, Yanping; Xie, Zhiyuan; Alshanqeeti, Ali S; Zhang, Yanru; Yao, Qiulin; Al-Shomrani, Badr M; Zhang, Dong; Li, Jiang; Manee, Manee M; Yang, Zili; Yang, Linfeng; Liu, Yiyi; Zhang, Jilin; Altammami, Musaad A; Wang, Shenyuan; Yu, Lili; Zhang, Wenbin; Liu, Sanyang; Ba, La; Liu, Chunxia; Yang, Xukui; Meng, Fanhua; Wang, Shaowei; Li, Lu; Li, Erli; Li, Xueqiong; Wu, Kaifeng; Zhang, Shu; Wang, Junyi; Yin, Ye; Yang, Huanming; Al-Swailem, Abdulaziz M; Wang, Jun

2014-10-21

Bactrian camel (Camelus bactrianus), dromedary (Camelus dromedarius) and alpaca (Vicugna pacos) are economically important livestock. Although the Bactrian camel and dromedary are large, typically arid-desert-adapted mammals, alpacas are adapted to plateaus. Here we present high-quality genome sequences of these three species. Our analysis reveals the demographic history of these species since the Tortonian Stage of the Miocene and uncovers a striking correlation between large fluctuations in population size and geological time boundaries. Comparative genomic analysis reveals complex features related to desert adaptations, including fat and water metabolism, stress responses to heat, aridity, intense ultraviolet radiation and choking dust. Transcriptomic analysis of Bactrian camels further reveals unique osmoregulation, osmoprotection and compensatory mechanisms for water reservation underpinned by high blood glucose levels. We hypothesize that these physiological mechanisms represent kidney evolutionary adaptations to the desert environment. This study advances our understanding of camelid evolution and the adaptation of camels to arid-desert environments.

Release of dissolved nitrogen from water during depressurization

NASA Technical Reports Server (NTRS)

Simoneau, R. J.

1978-01-01

Experiments were run to study depressurization of water containing various concentrations of dissolved nitrogen gas, the primary case being room temperature water saturated with nitrogen at 4 MPa. In a static depressurization experiment, water with very high nitrogen content was depressurized at rates from 0.09 to 0.50 MPa per second and photographed with high speed movies. The pictures showed that the bubble population at a given pressure increased strongly with decreasing depressurization rate. Flow experiments were performed in an axisymmetric converging-diverging nozzle and in a two-dimensional converging nozzle with glass sidewalls. Depressurization gradients were roughly 500 to 1200 MPa per second. Both nozzles exhibited choked flow behavior even at nitrogen concentration levels as low as 4 percent of saturated. The flow rates were independent of concentration level and could be computed as incompressible water flow based on the difference between stagnation and throat pressures; however, the throat pressures were significantly different between the two nozzles.

Orally dissolving strips: A new approach to oral drug delivery system

PubMed Central

Bala, Rajni; Pawar, Pravin; Khanna, Sushil; Arora, Sandeep

2013-01-01

Recently, fast dissolving films are gaining interest as an alternative of fast dissolving tablets. The films are designed to dissolve upon contact with a wet surface, such as the tongue, within a few seconds, meaning the consumer can take the product without need for additional liquid. This convenience provides both a marketing advantage and increased patient compliance. As the drug is directly absorbed into systemic circulation, degradation in gastrointestinal tract and first pass effect can be avoided. These points make this formulation most popular and acceptable among pediatric and geriatric patients and patients with fear of choking. Over-the-counter films for pain management and motion sickness are commercialized in the US markets. Many companies are utilizing transdermal drug delivery technology to develop thin film formats. In the present review, recent advancements regarding fast dissolving buccal film formulation and their evaluation parameters are compiled. PMID:24015378

The coral reefs optimization algorithm: a novel metaheuristic for efficiently solving optimization problems.

PubMed

Salcedo-Sanz, S; Del Ser, J; Landa-Torres, I; Gil-López, S; Portilla-Figueras, J A

2014-01-01

This paper presents a novel bioinspired algorithm to tackle complex optimization problems: the coral reefs optimization (CRO) algorithm. The CRO algorithm artificially simulates a coral reef, where different corals (namely, solutions to the optimization problem considered) grow and reproduce in coral colonies, fighting by choking out other corals for space in the reef. This fight for space, along with the specific characteristics of the corals' reproduction, produces a robust metaheuristic algorithm shown to be powerful for solving hard optimization problems. In this research the CRO algorithm is tested in several continuous and discrete benchmark problems, as well as in practical application scenarios (i.e., optimum mobile network deployment and off-shore wind farm design). The obtained results confirm the excellent performance of the proposed algorithm and open line of research for further application of the algorithm to real-world problems.

[The possibilities for the expert assessment of the influence of the structural features of a hunting weapon barrel on the characteristics of injuries inflicted by the multi-element ammunition in a cylindrical container].

PubMed

Makarov, I Yu; Suvorov, A S; Lorents, A S

The objective of the present study was to analyze the available information contained in the special literature concerning the possibilities for the expert assessment of the influence of the constructive and ballistic characteristics of hunting weapon barrels («cylinder» versus «choke») and their regular ammunition (equipped with pellets placed in a special wad-container and without it) on the mechanisms of damage formation. It was shown that the barrel muzzle narrowing produces the well apparent effect on the process of formation and release of all the damaging factors of the shot which makes it difficult to diagnose the resultant damage. It is concluded that the use of shooting ammunition with the pellets enclosed in wad-containers creates the objective prerequisite for the differentiation between its different types.

Improved equivalent circuit for twin slot terahertz receivers

NASA Technical Reports Server (NTRS)

McGrath, W. R.

2002-01-01

Series-fed coplanar waveguide embedding circuits are being developed for terahertz mixers using, in particular, submicron-sized superconducting devices, such as hot electron bolometers as the nonlinear element. Although these mixers show promising performance, they usually also show a considerable downward shift in the center frequency, when compared with simulations obtained by using simplified models. This makes it very difficult to design low-noise mixers for a given THz frequency. This shiftis principally caused by parasitics due to the extremely small details (in terms of wavelength) of the device, and by the electrical properties of the RF choke filter in the DC/IF line. In this paper, we present an improved equivalent network model of such mixer circuits which agrees with measured results at THz frequencies and we propose a new set of THz bolometric mixers that have been fabricated and are currently being tested.

Illuminating gravitational waves: A concordant picture of photons from a neutron star merger

DOE PAGES

Kasliwal, M. M.; Nakar, E.; Singer, L. P.; ...

2017-10-16

Merging neutron stars offer an excellent laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart (EM170817) with gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic data set, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultrarelativistic jets. Instead, we suggest that breakout of a wide-angle, mildly relativistic cocoon engulfing the jet explains the low-luminosity gamma rays, the high-luminosity ultraviolet-optical-infrared, and themore » delayed radio and x-ray emission. We posit that all neutron star mergers may lead to a wide-angle cocoon breakout, sometimes accompanied by a successful jet and sometimes by a choked jet.« less

Foreign bodies in the larynx and tracheobronchial tree in children. A review of 225 cases.

PubMed

Rothmann, B F; Boeckman, C R

1980-01-01

In a study of 225 patients with foreign bodies in the larynx, trachea and bronchi, 77% were 36 months of age or less. The male-female ratio was 2:1. Food or food derivatives were the causative agent in 70% of the cases, with 38% due to a portion of nut. The foreign body involved the right and left bronchus with equal frequency. A choking episode followed by an audible wheeze (55%) was the most common presenting complaint. Obstructive emphysema was demonstrated in 60% and was best demonstrated by inspiration-expiration chest roentgenograms or fluoroscopy. A radio-opaque object was seen in 13%. Two hundred ten foreign objects (93%) were removed by endoscopy. Four patients required pulmonary resection for bronchiectasis and in three patients bronchotomy was performed. Five patients expelled the foreign body spontaneously, two patients were transferred to another hospital, and one foreign body was not recovered. There was no mortality.

Pediatric airway foreign bodies.

PubMed

Fitzpatrick, P C; Guarisco, J L

1998-04-01

Foreign body aspiration (FBA) is a leading cause of accidental death in children less than one year old and is the cause of death in 7% of children less than four. Food items, especially peanuts, are the most common items aspirated in infants and toddlers, whereas older children are more likely to aspirate non-food items such as pen caps, pins, and paper clips. A high degree of suspicion is required to diagnose FBA. A history of a witnessed choking episode is most important in early diagnosis. An asymptomatic period is common after aspiration and contributes to a delay in diagnosis of greater than one week in 12% to 26% of patients. This delay in diagnosis causes increased morbidity from bronchial inflammation, obstruction, and pneumonia which is resistant to treatment. Prompt endoscopic removal of the foreign body with an open rigid bronchoscope under general anesthesia is the mainstay of therapy.

Numerical investigation & comparison of a tandem-bladed turbocharger centrifugal compressor stage with conventional design

NASA Astrophysics Data System (ADS)

Danish, Syed Noman; Qureshi, Shafiq Rehman; EL-Leathy, Abdelrahman; Khan, Salah Ud-Din; Umer, Usama; Ma, Chaochen

2014-12-01

Extensive numerical investigations of the performance and flow structure in an unshrouded tandem-bladed centrifugal compressor are presented in comparison to a conventional compressor. Stage characteristics are explored for various tip clearance levels, axial spacings and circumferential clockings. Conventional impeller was modified to tandem-bladed design with no modifications in backsweep angle, meridional gas passage and camber distributions in order to have a true comparison with conventional design. Performance degradation is observed for both the conventional and tandem designs with increase in tip clearance. Linear-equation models for correlating stage characteristics with tip clearance are proposed. Comparing two designs, it is clearly evident that the conventional design shows better performance at moderate flow rates. However; near choke flow, tandem design gives better results primarily because of the increase in throat area. Surge point flow rate also seems to drop for tandem compressor resulting in increased range of operation.

An evaluation of 1D loss model collections for the off-design performance prediction of automotive turbocharger compressors

NASA Astrophysics Data System (ADS)

Harley, P.; Spence, S.; Early, J.; Filsinger, D.; Dietrich, M.

2013-12-01

Single-zone modelling is used to assess different collections of impeller 1D loss models. Three collections of loss models have been identified in literature, and the background to each of these collections is discussed. Each collection is evaluated using three modern automotive turbocharger style centrifugal compressors; comparisons of performance for each of the collections are made. An empirical data set taken from standard hot gas stand tests for each turbocharger is used as a baseline for comparison. Compressor range is predicted in this study; impeller diffusion ratio is shown to be a useful method of predicting compressor surge in 1D, and choke is predicted using basic compressible flow theory. The compressor designer can use this as a guide to identify the most compatible collection of losses for turbocharger compressor design applications. The analysis indicates the most appropriate collection for the design of automotive turbocharger centrifugal compressors.

Chew on This: Not All First Finger Foods Are Created Equal.

PubMed

Awadalla, Nicol; Pham, Tammy; Milanaik, Ruth

2017-10-01

The American Academy of Pediatrics (AAP) recommends when to start first finger foods (FFFs) and what types of foods to start with, but it is unclear whether products marketed as FFF comply with these recommendations. We evaluated FFF products for compliance with AAP recommendations and product safety using 41 adult product testers, who were asked to dissolve each product in their mouth. Product characteristics, comments pertaining to product safety, and time to dissolve each product were recorded. Only 2 products met all AAP criteria, and safety concerns were raised for an additional 2 products. One product showed a large change in dissolvability after being left out of original packaging. Consumers should not assume that products marketed for infant/toddler consumption comply with AAP recommendations. Also, products left out of original packaging may change consistency, presenting a choking hazard. Additional research is warranted to guide the development of regulations surrounding labeling and marketing of these foods.

Think twice: misleading food-induced respiratory symptoms in children with food allergy.

PubMed

Ahrens, B; Mehl, A; Lau, S; Kroh, L; Magdorf, K; Wahn, U; Beyer, K; Niggemann, B

2014-03-01

Reported food-related symptoms of patients may sometimes be misleading. A correct delineation of food-induced symptoms is often difficult and various differential diagnoses have to be considered. We report on two cases of food-induced, predominantly respiratory symptoms (in one case life-threatening) in children with food allergy. First, a two-year-old boy with no history of allergies and suspected foreign body aspiration which was finally diagnosed as an anaphylactic reaction to fish, and secondly a six-year-old girl with multiple food allergies and allergic asthma who during an electively performed oral food challenge developed severe respiratory distress, drop in blood pressure, and asphyxia not due to an anaphylactic reaction but due to choking on an unnoticed sweet. These two cases represent challenging, life-threatening symptom constellations involving food-induced reactions in food allergic children, reminding us to question first impressions. © 2013 Wiley Periodicals, Inc.

Application of microturbines to control emissions from associated gas

DOEpatents

Schmidt, Darren D.

2013-04-16

A system for controlling the emission of associated gas produced from a reservoir. In an embodiment, the system comprises a gas compressor including a gas inlet in fluid communication with an associated gas source and a gas outlet. The gas compressor adjusts the pressure of the associated gas to produce a pressure-regulated associated gas. In addition, the system comprises a gas cleaner including a gas inlet in fluid communication with the outlet of the gas compressor, a fuel gas outlet, and a waste product outlet. The gas cleaner separates at least a portion of the sulfur and the water from the associated gas to produce a fuel gas. Further, the system comprises a gas turbine including a fuel gas inlet in fluid communication with the fuel gas outlet of the gas cleaner and an air inlet. Still further, the system comprises a choke in fluid communication with the air inlet.

Reactive melt infiltration of silicon-molybdenum alloys into microporous carbon preforms

NASA Technical Reports Server (NTRS)

Singh, M.; Behrendt, D. R.

1995-01-01

Investigations on the reactive melt infiltration of silicon-1.7 and 3.2 at.% molybdenum alloys into microporous carbon preforms have been carried out by modeling, differential thermal analysis (DTA), and melt infiltration experiments. These results indicate that the pore volume fraction of the carbon preform is a very important parameter in determining the final composition of the reaction-formed silicon carbide and the secondary phases. Various undesirable melt infiltration results, e.g. choking-off, specimen cracking, silicon veins, and lake formation, and their correlation with inadequate preform properties are presented. The liquid silicon-carbon reaction exotherm temperatures are influenced by the pore and carbon particle size of the preform and the compositions of infiltrants. Room temperature flexural strength and fracture toughness of materials made by the silicon-3.2 at.% molybdenum alloy infiltration of medium pore size preforms are also discussed.

Compliance of middle school-aged babysitters in central Pennsylvania with national recommendations for emergency preparedness and safety practices.

PubMed

Hackman, Nicole M; Cass, Katie; Olympia, Robert P

2012-06-01

To determine the compliance of middle school-aged babysitters with national recommendations for emergency preparedness and safety practices. A prospective, self-administered questionnaire-based study was conducted at 3 middle schools in central Pennsylvania. A total of 1364 questionnaires were available for analysis. Responding babysitters (n = 890) reported previous training that included babysitter (21%), first aid (64%), and cardiopulmonary resuscitation (59%) training. Reported unsafe babysitter practices were leaving a child unattended (36%) and opening the door to a stranger (24%). The most common emergency experience encountered by responding babysitters included cut or scrape (83%), burns (28%), and choking (14%). Ten percent of responding babysitters have activated the 911 system. Middle school-aged babysitters will likely encounter common household emergencies and therefore benefit from first aid training; however, very little difference in safety knowledge was found between trained and untrained babysitters, suggesting modifications in babysitter training programs may be required.

Surface-enhanced Raman as a water monitor for warfare agents

NASA Astrophysics Data System (ADS)

Spencer, Kevin M.; Sylvia, James M.; Clauson, Susan L.; Janni, James A.

2002-02-01

The threat of chemical warfare agents being released upon civilian and military personnel continues to escalate. One aspect of chemical preparedness is to analyze and protect the portable water supply for the military. Chemical nerve, blister, and choking agents, as well as biological threats must all be analyzed and low limits of detection must be verified. For chemical agents, this generally means detection down to the low ppb levels. Surface-Enhanced Raman Spectroscopy (SERS) is a spectroscopic technique that can detect trace levels of contaminants directly in the aqueous environment. In this paper, results are presented on the use of SERS to detect chemical and biological agent simulants with an end goal of creating a Joint Service Agent Water Monitor. Detection of cyanide, 2-chloroethyl ethyl sulfide, phosphonates, Gram-positive and Gram-negative bacteria using SERS has been performed and is discussed herein. Aspects of transferring laboratory results to an unattended field instrument are also discussed.

A Venturi microregulator array module for distributed pressure control

PubMed Central

Chang, Dustin S.; Langelier, Sean M.; Zeitoun, Ramsey I.

2010-01-01

Pressure-driven flow control systems are a critical component in many microfluidic devices. Compartmentalization of this functionality into a stand-alone module possessing a simple interface would allow reduction of the number of pneumatic interconnects required for fluidic control. Ideally, such a module would also be sufficiently compact for implementation in portable platforms. In our current work, we show the feasibility of using a modular array of Venturi pressure microregulators for coordinated droplet manipulation. The arrayed microregulators share a single pressure input and are capable of outputting electronically controlled pressures that can be independently set between ±1.3 kPa. Because the Venturi microregulator operates by thermal perturbation of a choked gas flow, this output range corresponds to a temperature variation between 20 and 95°C. Using the array, we demonstrate loading, splitting, merging, and independent movement of multiple droplets in a valveless microchannel network. PMID:20938490

Panic attack symptoms differentiate patients with epilepsy from those with psychogenic nonepileptic spells (PNES).

PubMed

Hendrickson, Rick; Popescu, Alexandra; Dixit, Ronak; Ghearing, Gena; Bagic, Anto

2014-08-01

Psychogenic nonepileptic spells (PNES) are frequently challenging to differentiate from epileptic seizures. The experience of panic attack symptoms during an event may assist in distinguishing PNES from seizures secondary to epilepsy. A retrospective analysis of 354 patients diagnosed with PNES (N=224) or with epilepsy (N=130) investigated the thirteen Diagnostic and Statistical Manual-IV-Text Revision panic attack criteria endorsed by the two groups. We found a statistically higher mean number of symptoms reported by patients with PNES compared with those with epilepsy. In addition, the majority of the panic attack symptoms including heart palpitations, sweating, shortness of breath, choking feeling, chest discomfort, dizziness/unsteadiness, derealization or depersonalization, fear of dying, paresthesias, and chills or hot flashes were significantly more frequent in those with PNES. As patients with PNES frequently have poor clinical outcomes, treatment addressing the anxiety symptomatology may be beneficial. Copyright © 2014 Elsevier Inc. All rights reserved.

Illuminating gravitational waves: A concordant picture of photons from a neutron star merger

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kasliwal, M. M.; Nakar, E.; Singer, L. P.

Merging neutron stars offer an excellent laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart (EM170817) with gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic data set, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultrarelativistic jets. Instead, we suggest that breakout of a wide-angle, mildly relativistic cocoon engulfing the jet explains the low-luminosity gamma rays, the high-luminosity ultraviolet-optical-infrared, and themore » delayed radio and x-ray emission. We posit that all neutron star mergers may lead to a wide-angle cocoon breakout, sometimes accompanied by a successful jet and sometimes by a choked jet.« less

Impact of impedance unbalance on the efficiency of electricity transmission and distribution - A case study

NASA Astrophysics Data System (ADS)

Pavlov, L'uboš; Skurčák, L'uboš; Chovanec, Juraj; Altus, Juraj

2017-11-01

This article is devoted to the analysis of the possible influence of impedance asymmetry on the efficiency of electricity transmission and distribution in the electricity system in Slovakia, at a voltage level of 110 kV - 400 kV, using synchronic phasor monitoring results. For simplicity of calculations, in practice, the impedance imbalance from mutual interfacial inductive capacitances bonds is neglected. In this way, the 3-phase network is interpreted as symmetrical in the calculations. In this case, it is possible to determine only some components of losses (ohmic losses, corona loss, leakages, etc). The influence of impedance asymmetry can be quantified by calculation using the results of the monitoring of the synchronous phasors of selected electricity system elements (OHL, transformer, choke) or by 3-phase modelling of real system elements. frequency to test the transformer for induced over voltage test, and its characteristics is analysed.

Illuminating gravitational waves: A concordant picture of photons from a neutron star merger

NASA Astrophysics Data System (ADS)

Kasliwal, M. M.; Nakar, E.; Singer, L. P.; Kaplan, D. L.; Cook, D. O.; Van Sistine, A.; Lau, R. M.; Fremling, C.; Gottlieb, O.; Jencson, J. E.; Adams, S. M.; Feindt, U.; Hotokezaka, K.; Ghosh, S.; Perley, D. A.; Yu, P.-C.; Piran, T.; Allison, J. R.; Anupama, G. C.; Balasubramanian, A.; Bannister, K. W.; Bally, J.; Barnes, J.; Barway, S.; Bellm, E.; Bhalerao, V.; Bhattacharya, D.; Blagorodnova, N.; Bloom, J. S.; Brady, P. R.; Cannella, C.; Chatterjee, D.; Cenko, S. B.; Cobb, B. E.; Copperwheat, C.; Corsi, A.; De, K.; Dobie, D.; Emery, S. W. K.; Evans, P. A.; Fox, O. D.; Frail, D. A.; Frohmaier, C.; Goobar, A.; Hallinan, G.; Harrison, F.; Helou, G.; Hinderer, T.; Ho, A. Y. Q.; Horesh, A.; Ip, W.-H.; Itoh, R.; Kasen, D.; Kim, H.; Kuin, N. P. M.; Kupfer, T.; Lynch, C.; Madsen, K.; Mazzali, P. A.; Miller, A. A.; Mooley, K.; Murphy, T.; Ngeow, C.-C.; Nichols, D.; Nissanke, S.; Nugent, P.; Ofek, E. O.; Qi, H.; Quimby, R. M.; Rosswog, S.; Rusu, F.; Sadler, E. M.; Schmidt, P.; Sollerman, J.; Steele, I.; Williamson, A. R.; Xu, Y.; Yan, L.; Yatsu, Y.; Zhang, C.; Zhao, W.

2017-12-01

Merging neutron stars offer an excellent laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart (EM170817) with gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic data set, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultrarelativistic jets. Instead, we suggest that breakout of a wide-angle, mildly relativistic cocoon engulfing the jet explains the low-luminosity gamma rays, the high-luminosity ultraviolet-optical-infrared, and the delayed radio and x-ray emission. We posit that all neutron star mergers may lead to a wide-angle cocoon breakout, sometimes accompanied by a successful jet and sometimes by a choked jet.

As International as They Would Let Us Be

NASA Astrophysics Data System (ADS)

Trimble, V.

2015-08-01

Astronomy has always crossed borders, continents, and oceans. AAVSO itself has roughly half its membership residing outside the USA. In this excessively long paper, I look briefly at ancient and medieval beginnings and more extensively at the 18th and 19th centuries, plunge into the tragedies associated with World War I, and then try to say something relatively cheerful about subsequent events. Most of the people mentioned here you will have heard of before (Eratosthenes, Copernicus, Kepler, Olbers, Lockyer, Eddington…) others, just as important, perhaps not (von Zach, Gould, Argelander, Freundlich…). Division into heroes and villains is neither necessary nor possible, though some of the stories are tragic. In the end, all one can really say about astronomers' efforts to keep open channels of communication that others wanted to choke off is, "the best we can do is the best we can do."

Neurogenic [corrected] and oropharyngeal dysphagia.

PubMed

Rofes, Laia; Clavé, Pere; Ouyang, Ann; Scharitzer, Martina; Pokieser, Peter; Vilardell, Natalia; Ortega, Omar

2013-10-01

Oropharyngeal dysphagia (OD) is a swallowing disorder caused by congenital abnormalities and structural damage and disease-associated damage of the oral cavity, pharynx, and upper esophageal sphincter. Patients with OD lack the protective mechanisms necessary for effective swallowing, exhibiting difficulty controlling food in the mouth and initiating a swallow, leading to choking, coughing, and nasal regurgitation. OD is a major risk factor for malnutrition, dehydration, and aspiration pneumonia. The following on OD includes commentaries on the application of simulation of oropharyngeal transient receptor potential vanilloid 1 (TRPV1) and maneuvers like the Shaker exercise to improve the safety and efficacy of swallow in OD patients; the prevalence of esophageal pathologies in OD patients and the need to evaluate the esophagus, esophagogastric junction, and stomach; and strategies for clinical screening to detect OD and aspiration among high-risk patients and to improve oral health care, maintain nutrition and hydration, and prevent aspiration pneumonia. © 2013 New York Academy of Sciences.

Hagfish predatory behaviour and slime defence mechanism

PubMed Central

Zintzen, Vincent; Roberts, Clive D.; Anderson, Marti J.; Stewart, Andrew L.; Struthers, Carl D.; Harvey, Euan S.

2011-01-01

Hagfishes (Myxinidae), a family of jawless marine pre-vertebrates, hold a unique evolutionary position, sharing a joint ancestor with the entire vertebrate lineage. They are thought to fulfil primarily the ecological niche of scavengers in the deep ocean. However, we present new footage from baited video cameras that captured images of hagfishes actively preying on other fish. Video images also revealed that hagfishes are able to choke their would-be predators with gill-clogging slime. This is the first time that predatory behaviour has been witnessed in this family, and also demonstrates the instantaneous effectiveness of hagfish slime to deter fish predators. These observations suggest that the functional adaptations and ecological role of hagfishes, past and present, might be far more diverse than previously assumed. We propose that the enduring success of this oldest extant family of fishes over 300 million years could largely be due to their unique combination of functional traits. PMID:22355648

Rapid response to climate change in a marginal sea.

PubMed

Schroeder, K; Chiggiato, J; Josey, S A; Borghini, M; Aracri, S; Sparnocchia, S

2017-06-22

The Mediterranean Sea is a mid-latitude marginal sea, particularly responsive to climate change as reported by recent studies. The Sicily Channel is a choke point separating the sea in two main basins, the Eastern Mediterranean Sea and the Western Mediterranean Sea. Here, we report and analyse a long-term record (1993-2016) of the thermohaline properties of the Intermediate Water that crosses the Sicily Channel, showing increasing temperature and salinity trends much stronger than those observed at intermediate depths in the global ocean. We investigate the causes of the observed trends and in particular determine the role of a changing climate over the Eastern Mediterranean, where the Intermediate Water is formed. The long-term Sicily record reveals how fast the response to climate change can be in a marginal sea like the Mediterranean Sea compared to the global ocean, and demonstrates the essential role of long time series in the ocean.

Shock wave calibration of under-expanded natural gas fuel jets

NASA Astrophysics Data System (ADS)

White, T. R.; Milton, B. E.

2008-10-01

Natural gas, a fuel abundant in nature, cannot be used by itself in conventional diesel engines because of its low cetane number. However, it can be used as the primary fuel with ignition by a pilot diesel spray. This is called dual-fuelling. The gas may be introduced either into the inlet manifold or, preferably, directly into the cylinder where it is injected as a short duration, intermittent, sonic jet. For accurate delivery in the latter case, a constant flow-rate from the injector is required into the constantly varying pressure in the cylinder. Thus, a sonic (choked) jet is required which is generally highly under-expanded. Immediately at the nozzle exit, a shock structure develops which can provide essential information about the downstream flow. This shock structure, generally referred to as a “barrel” shock, provides a key to understanding the full injection process. It is examined both experimentally and numerically in this paper.

Aerodynamic and acoustic behavior of a YF-12 inlet at static conditions

NASA Technical Reports Server (NTRS)

Bangert, L. H.; Feltz, E. P.; Godby, L. A.; Miller, L. D.

1981-01-01

An aeroacoustic test program to determine the cause of YF-12 inlet noise suppression was performed with a YF-12 aircraft at ground static conditions. Data obtained over a wide range of engine speeds and inlet configurations are reported. Acoustic measurements were made in the far field and aerodynamic and acoustic measurements were made inside the inlet. The J-58 test engine was removed from the aircraft and tested separately with a bellmouth inlet. The far field noise level was significantly lower for the YF-12 inlet than for the bellmouth inlet at engine speeds above 5500 rpm. There was no evidence that noise suppression was caused by flow choking. Multiple pure tones were reduced and the spectral peak near the blade passing frequency disappeared in the region of the spike support struts at engine speeds between 6000 and 6600 rpm.

CAD of 0.1- to 10-GHz GaAs MMIC SPST switch

NASA Astrophysics Data System (ADS)

Yadav, Ramchandra; Kirty, V. S. R.

1998-04-01

The design of the SPST switch provides an insertion loss less than 2 dB, isolation more than 40 dB and return loss better than 17.5 dB in the frequency range of 0.1 GHz to 10 GHz. The insertion loss is improved by treating SPST switch as a 50 (Omega) artificial transmission line with incorporation of inductor in series arm and the capacitance of MESFET in the shunt arm. High isolation is ensured by the lower value of `ON' resistance of MESFET in shunt arm. Also good return loss is achieved by paralleling a 50 (Omega) resistor with capacitance of MESFET in series arm. The absence of DC blocking capacitors and replacement of large value bias chokes with 5 K(Omega) resistors effectively improved the performance of SPST switch at low frequency and also reduced the chip size. The overall chip dimension is 2.2 mm X 1.7 mm.

The Coral Reefs Optimization Algorithm: A Novel Metaheuristic for Efficiently Solving Optimization Problems

PubMed Central

Salcedo-Sanz, S.; Del Ser, J.; Landa-Torres, I.; Gil-López, S.; Portilla-Figueras, J. A.

2014-01-01

This paper presents a novel bioinspired algorithm to tackle complex optimization problems: the coral reefs optimization (CRO) algorithm. The CRO algorithm artificially simulates a coral reef, where different corals (namely, solutions to the optimization problem considered) grow and reproduce in coral colonies, fighting by choking out other corals for space in the reef. This fight for space, along with the specific characteristics of the corals' reproduction, produces a robust metaheuristic algorithm shown to be powerful for solving hard optimization problems. In this research the CRO algorithm is tested in several continuous and discrete benchmark problems, as well as in practical application scenarios (i.e., optimum mobile network deployment and off-shore wind farm design). The obtained results confirm the excellent performance of the proposed algorithm and open line of research for further application of the algorithm to real-world problems. PMID:25147860

Preliminary dynamic tests of a flight-type ejector

NASA Technical Reports Server (NTRS)

Drummond, Colin K.

1992-01-01

A thrust augmenting ejector was tested to provide experimental data to assist in the assessment of theoretical models to predict duct and ejector fluid-dynamic characteristics. Eleven full-scale thrust augmenting ejector tests were conducted in which a rapid increase in the ejector nozzle pressure ratio was effected through a unique bypass/burst-disk subsystem. The present work examines two cases representative of the test performance window. In the first case, the primary nozzle pressure ration (NPR) increased 36 percent from one unchoked (NPR = 1.29) primary flow condition to another (NPR = 1.75) over a 0.15 second interval. The second case involves choked primary flow conditions, where a 17 percent increase in primary nozzle flowrate (from NPR = 2.35 to NPR = 2.77) occurred over approximately 0.1 seconds. Transient signal treatment of the present dataset is discussed and initial interpretations of the results are compared with theoretical predictions for a similar STOVL ejector model.

Oral trauma and dental emergency management recommendations of first-aid textbooks and manuals.

PubMed

Zadik, Yehuda

2007-10-01

The recommendations of oral trauma and dental emergencies management of nine first-aid textbooks and manuals from the last two decades were evaluated. Only one book includes all the relevant topics: dental anatomy, management of tooth luxations and avulsion, tooth fracture, mandible dislocation, jaw fracture, intraoral bleeding and dental pain. Two books recommend self-replantation of an avulsed tooth, but four books detail the storage media and evaluate the importance of a quick referral to a dental surgery. In three first-aid books, the only mention of oral trauma is the hazard of choking from tooth fragments, and in one other book, only mandible dislocation is mentioned as oral trauma. The insufficient information of oral trauma management in these first-aid texts partly explains the previous reports of poor and inadequate knowledge in that topic among medics, teachers and the general public.

A Case of Atypical Skull Base Osteomyelitis with Septic Pulmonary Embolism

PubMed Central

Lee, Soon Jung; Weon, Young Cheol; Cha, Hee Jeong; Kim, Sun Young; Seo, Kwang Won; Jegal, Yangjin; Ahn, Jong-Joon

2011-01-01

Skull base osteomyelitis (SBO) is difficult to diagnose when a patient presents with multiple cranial nerve palsies but no obvious infectious focus. There is no report about SBO with septic pulmonary embolism. A 51-yr-old man presented to our hospital with headache, hoarseness, dysphagia, frequent choking, fever, cough, and sputum production. He was diagnosed of having masked mastoiditis complicated by SBO with multiple cranial nerve palsies, sigmoid sinus thrombosis, and septic pulmonary embolism. We successfully treated him with antibiotics and anticoagulants alone, with no surgical intervention. His neurologic deficits were completely recovered. Decrease of pulmonary nodules and thrombus in the sinus was evident on the follow-up imaging one month later. In selected cases of intracranial complications of SBO and septic pulmonary embolism, secondary to mastoiditis with early response to antibiotic therapy, conservative treatment may be considered and surgical intervention may be withheld. PMID:21738354

Computational Fluid Dynamics Modeling of a Supersonic Nozzle and Integration into a Variable Cycle Engine Model

NASA Technical Reports Server (NTRS)

Connolly, Joseph W.; Friedlander, David; Kopasakis, George

2015-01-01

This paper covers the development of an integrated nonlinear dynamic simulation for a variable cycle turbofan engine and nozzle that can be integrated with an overall vehicle Aero-Propulso-Servo-Elastic (APSE) model. A previously developed variable cycle turbofan engine model is used for this study and is enhanced here to include variable guide vanes allowing for operation across the supersonic flight regime. The primary focus of this study is to improve the fidelity of the model's thrust response by replacing the simple choked flow equation convergent-divergent nozzle model with a MacCormack method based quasi-1D model. The dynamic response of the nozzle model using the MacCormack method is verified by comparing it against a model of the nozzle using the conservation element/solution element method. A methodology is also presented for the integration of the MacCormack nozzle model with the variable cycle engine.

Computational Fluid Dynamics Modeling of a Supersonic Nozzle and Integration into a Variable Cycle Engine Model

NASA Technical Reports Server (NTRS)

Connolly, Joseph W.; Friedlander, David; Kopasakis, George

2014-01-01

This paper covers the development of an integrated nonlinear dynamic simulation for a variable cycle turbofan engine and nozzle that can be integrated with an overall vehicle Aero-Propulso-Servo-Elastic (APSE) model. A previously developed variable cycle turbofan engine model is used for this study and is enhanced here to include variable guide vanes allowing for operation across the supersonic flight regime. The primary focus of this study is to improve the fidelity of the model's thrust response by replacing the simple choked flow equation convergent-divergent nozzle model with a MacCormack method based quasi-1D model. The dynamic response of the nozzle model using the MacCormack method is verified by comparing it against a model of the nozzle using the conservation element/solution element method. A methodology is also presented for the integration of the MacCormack nozzle model with the variable cycle engine.

HOM-Free Linear Accelerating Structure for e+ e- Linear Collider at C-Band

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kubo, Kiyoshi

2003-07-07

HOM-free linear acceleration structure using the choke mode cavity (damped cavity) is now under design for e{sup +}e{sup -} linear collider project at C-band frequency (5712 MHz). Since this structure shows powerful damping effect on most of all HOMs, there is no multibunch problem due to long range wakefields. The structure will be equipped with the microwave absorbers in each cells and also the in-line dummy load in the last few cells. The straightness tolerance for 1.8 m long structure is closer than 30 {micro}m for 25% emittance dilution limit, which can be achieved by standard machining and braising techniques.more » Since it has good vacuum pumping conductance through annular gaps in each cell, instabilities due to the interaction of beam with the residual-gas and ions can be minimized.« less

Prediction of Sound Waves Propagating Through a Nozzle Without/With a Shock Wave Using the Space-Time CE/SE Method

NASA Technical Reports Server (NTRS)

Wang, Xiao-Yen; Chang, Sin-Chung; Jorgenson, Philip C. E.

2000-01-01

The benchmark problems in Category 1 (Internal Propagation) of the third Computational Aeroacoustics (CAA) Work-shop sponsored by NASA Glenn Research Center are solved using the space-time conservation element and solution element (CE/SE) method. The first problem addresses the propagation of sound waves through a nearly choked transonic nozzle. The second one concerns shock-sound interaction in a supersonic nozzle. A quasi one-dimension CE/SE Euler solver for a nonuniform mesh is developed and employed to solve both problems. Numerical solutions are compared with the analytical solution for both problems. It is demonstrated that the CE/SE method is capable of solving aeroacoustic problems with/without shock waves in a simple way. Furthermore, the simple nonreflecting boundary condition used in the CE/SE method which is not based on the characteristic theory works very well.

Syndecan promotes axon regeneration by stabilizing growth cone migration

PubMed Central

Edwards, Tyson J.; Hammarlund, Marc

2014-01-01

SUMMARY Growth cones facilitate the repair of nervous system damage by providing the driving force for axon regeneration. Using single-neuron laser axotomy and in vivo time-lapse imaging, we show that syndecan, a heparan sulfate (HS) proteoglycan, is required for growth cone function during axon regeneration in C. elegans. In the absence of syndecan, regenerating growth cones form but are unstable and collapse, decreasing the effective growth rate and impeding regrowth to target cells. We provide evidence that syndecan has two distinct functions during axon regeneration: 1) a canonical function in axon guidance that requires expression outside the nervous system and depends on HS chains, and 2) a novel intrinsic function in growth cone stabilization that is mediated by the syndecan core protein, independently of HS. Thus, syndecan is a novel regulator of a critical choke point in nervous system repair. PMID:25001284

Syndecan promotes axon regeneration by stabilizing growth cone migration.

PubMed

Edwards, Tyson J; Hammarlund, Marc

2014-07-10

Growth cones facilitate the repair of nervous system damage by providing the driving force for axon regeneration. Using single-neuron laser axotomy and in vivo time-lapse imaging, we show that syndecan, a heparan sulfate (HS) proteoglycan, is required for growth cone function during axon regeneration in C. elegans. In the absence of syndecan, regenerating growth cones form but are unstable and collapse, decreasing the effective growth rate and impeding regrowth to target cells. We provide evidence that syndecan has two distinct functions during axon regeneration: (1) a canonical function in axon guidance that requires expression outside the nervous system and depends on HS chains and (2) an intrinsic function in growth cone stabilization that is mediated by the syndecan core protein, independently of HS. Thus, syndecan is a regulator of a critical choke point in nervous system repair. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Cosmic Microwave Background Polarization Detector with High Efficiency, Broad Bandwidth, and Highly Symmetric Coupling to Transition Edge Sensor Bolometers

NASA Technical Reports Server (NTRS)

Wollack, E.; Cao, N.; Chuss, D.; Denis, K.; Hsieh, W.-T.; Moseley, S. Harvey; Schneider, G.; Stevenson, T.; Travers, D.; U-yen, K.

2008-01-01

Four probe antennas transfer signals from waveguide to microstrip lines. The probes not only provide broadband impedance matching, but also thermally isolate waveguide and detector. In addition, we developed a new photonic waveguide choke joint design, with four-fold symmetry, to suppress power leakage at the interface. We have developed facilities to test superconducting circuit elements using a cryogenic microwave probe station, and more complete systems in waveguide. We used the ring resonator shown below to measure a dielectric loss tangent < 7x10(exp -4) over 10 - 45 GHz. We have combined component simulations to predict the overall coupling from waveguide modes to bolometers. The result below shows the planar circuit and waveguide interface can utilize the high beam symmetry of HE11 circular feedhorns with > 99% coupling efficiency over 30% fractional bandwidth.

Evaporation of ice in planetary atmospheres - Ice-covered rivers on Mars

NASA Technical Reports Server (NTRS)

Wallace, D.; Sagan, C.

1979-01-01

The existence of ice covered rivers on Mars is considered. It is noted that the evaporation rate of water ice on the surface of a planet with an atmosphere involves an equilibrium between solar heating and radiative and evaporative cooling of the ice layer. It is determined that even with a mean Martian insolation rate above the ice of approximately 10 to the -8th g per sq cm/sec, a flowing channel of liquid water will be covered by ice which evaporates sufficiently slowly that the water below can flow for hundreds of kilometers even with modest discharges. Evaporation rates are calculated for a range of frictional velocities, atmospheric pressures, and insolations and it is suggested that some subset of observed Martian channels may have formed as ice-choked rivers. Finally, the exobiological implications of ice covered channels or lakes on Mars are discussed.

Does the early adopter catch the worm or choke on it? A reflective journey of the challenges of technology adoption in a health sciences education institution.

PubMed

Botha-Ravyse, Chrisna; Blignaut, Seugnet

2017-01-01

Early adoption of technology is a struggle well known to early adopters and now to me. Since the demand to use and implement technology in health professions' education has increased, I have been led to adopt various technologies, leading to many headaches. This paper addresses my experiences in developing and implementing technology in health science classrooms in a setting not adequately equipped to do so. After reflecting on my experiences, I conclude that it is crucial that systems help innovators and early adopters as they work to develop and implement teaching and learning technology. Technical decisions should address the needs of the higher education educator. In addition, once an institution chooses a specific technological approach, such as using e-guides, there should be resources in place to support the forerunners of these initiatives.

Burn Control Mechanisms in Tokamaks

NASA Astrophysics Data System (ADS)

Hill, M. A.; Stacey, W. M.

2015-11-01

Burn control and passive safety in accident scenarios will be an important design consideration in future tokamak reactors, in particular fusion-fission hybrid reactors, e.g. the Subcritical Advanced Burner Reactor. We are developing a burning plasma dynamics code to explore various aspects of burn control, with the intent to identify feedback mechanisms that would prevent power excursions. This code solves the coupled set of global density and temperature equations, using scaling relations from experimental fits. Predictions of densities and temperatures have been benchmarked against DIII-D data. We are examining several potential feedback mechanisms to limit power excursions: i) ion-orbit loss, ii) thermal instability density limits, iii) MHD instability limits, iv) the degradation of alpha-particle confinement, v) modifications to the radial current profile, vi) ``divertor choking'' and vii) Type 1 ELMs. Work supported by the US DOE under DE-FG02-00ER54538, DE-FC02-04ER54698.

Baby-Led Introduction to SolidS (BLISS) study: a randomised controlled trial of a baby-led approach to complementary feeding.

PubMed

Daniels, Lisa; Heath, Anne-Louise M; Williams, Sheila M; Cameron, Sonya L; Fleming, Elizabeth A; Taylor, Barry J; Wheeler, Ben J; Gibson, Rosalind S; Taylor, Rachael W

2015-11-12

In 2002, the World Health Organization recommended that the age for starting complementary feeding should be changed from 4 to 6 months of age to 6 months. Although this change in age has generated substantial debate, surprisingly little attention has been paid to whether advice on how to introduce complementary foods should also be changed. It has been proposed that by 6 months of age most infants will have developed sufficient motor skills to be able to feed themselves rather than needing to be spoon-fed by an adult. This has the potential to predispose infants to better growth by fostering better energy self-regulation, however no randomised controlled trials have been conducted to determine the benefits and risks of such a "baby-led" approach to complementary feeding. This is of particular interest given the widespread use of "Baby-Led Weaning" by parents internationally. The Baby-Led Introduction to SolidS (BLISS) study aims to assess the efficacy and acceptability of a modified version of Baby-Led Weaning that has been altered to address potential concerns with iron status, choking and growth faltering. The BLISS study will recruit 200 families from Dunedin, New Zealand, who book into the region's only maternity hospital. Parents will be randomised into an intervention (BLISS) or control group for a 12-month intervention with further follow-up at 24 months of age. Both groups will receive the standard Well Child care provided to all parents in New Zealand. The intervention group will receive additional parent contacts (n = 8) for support and education on BLISS from before birth to 12 months of age. Outcomes of interest include body mass index at 12 months of age (primary outcome), energy self-regulation, iron and zinc intake and status, diet quality, choking, growth faltering and acceptability to parents. This study is expected to provide insight into the feasibility of a baby-led approach to complementary feeding and the extent to which this method of feeding affects infant body weight, diet quality and iron and zinc status. Results of this study will provide important information for health care professionals, parents and health policy makers. Australian New Zealand Clinical Trials Registry ACTRN12612001133820 .

Numerical investigation of roughness effects in aircraft icing calculations

NASA Astrophysics Data System (ADS)

Matheis, Brian Daniel

2008-10-01

Icing codes are playing a role of increasing significance in the design and certification of ice protected aircraft surfaces. However, in the interest of computational efficiency certain small scale physics of the icing problem are grossly approximated by the codes. One such small scale phenomena is the effect of ice roughness on the development of the surface water film and on the convective heat transfer. This study uses computational methods to study the potential effect of ice roughness on both of these small scale phenomena. First, a two-dimensional condensed layer code is used to examine the effect of roughness on surface water development. It is found that the Couette approximation within the film breaks down as the wall shear goes to zero, depending on the film thickness. Roughness elements with initial flow separation in the air induce flow separation in the water layer at steady state, causing a trapping of the film. The amount of trapping for different roughness configurations is examined. Second, a three-dimensional incompressible Navier-Stokes code is developed to examine large scale ice roughness on the leading edge. The effect on the convective heat transfer and potential effect on the surface water dynamics is examined for a number of distributed roughness parameters including Reynolds number, roughness height, streamwise extent, roughness spacing and roughness shape. In most cases the roughness field increases the net average convective heat transfer on the leading edge while narrowing surface shear lines, indicating a choking of the surface water flow. Both effects show significant variation on the scale of the ice roughness. Both the change in heat transfer as well as the potential change in surface water dynamics are presented in terms of the development of singularities in the surface shear pattern. Of particular interest is the effect of the smooth zone upstream of the roughness which shows both a relatively large increase in convective heat transfer as well as excessive choking of the surface shear lines at the upstream end of the roughness field. A summary of the heat transfer results is presented for both the averaged heat transfer as well as the maximum heat transfer over each roughness element, indicating that the roughness Reynolds number is the primary parameter which characterizes the behavior of the roughness for the problem of interest.

Calibrating the Helium Pressurization System for the Space Shuttle Liquid-Hydrogen Tank

NASA Technical Reports Server (NTRS)

2008-01-01

Analysis of the results from the STS-114 tanking tests and subsequent launch called into question existing thermal and mass models of helium pressurization of the liquid hydrogen tank. This hydrogen tank, which makes up the bottom two-thirds of the External Tank, is pressurized prior to launch to avoid cavitation in the Shuttle Main Engine pumps. At about 2 minutes prior to launch, the main vent valve is closed, and pressurized helium flows into the tank ullage space to achieve set point pressure. As the helium gas cools, its pressure drops, calling for additional helium. Subsequent helium flows are provided in short, timed pulses. The number of pulses is taken as a rough leak indicator. An analysis of thermal models by Marshall Space Flight Center showed considerable uncertainty in the pressure-versus-time behavior of the helium ullage space and the ability to predict the number of pulses normally expected. Kennedy Space Center proposed to calibrate the dime-sized orifice, which together with valves, controls the helium flow quantity (Figure 1). Pressure and temperature sensors were installed to provide upstream and downstream measurements necessary to compute flow rate based on the orifice discharge coefficient. An assessment of flow testing with helium indicated an extremely costly use of this critical resource. In order to reduce costs, we proposed removing the orifices from each Mobile Launcher Platform (MLP) and asking Colorado Engineering Experiment Station Inc. (CEESI) to calibrate the flow. CEESI has a high-pressure air flow system with traceable flow meters capable of handling the large flow rates. However, literature research indicated that square-edged orifices of small diameters often exhibit significant hysteresis and nonrepeatability in the vicinity of choked or sonic flow. Fortunately, the MLP orifices behaved relatively well in testing (Figure 2). Using curve fitting of the air-flow data, in conjunction with ASME orifice modeling equations, a method of relating the helium mass flow to measured air flow data was obtained. This analysis showed that the highest uncertainty in flow occurred in the vicinity of the choking pressure ratio, as would be expected. In addition, analysis of typical flow pulses showed that most of the helium flow occurred either well below or well above this uncertain area. The final result is the ability to provide postlaunch estimates of helium mass flows that are within 1.5 percent of the actual value.

[Frequency and prevention of childhood domestic injury according to age].

PubMed

Kanaizumi, Shiomi; Shibata, Mariko; Miyazaki, Yukiko; Nakashita, Tomiko; Sakou, Keiko; Hoshino, Yasue; Ichinohe, Shinko; Ohno, Ayako; Manabe, Shigeo

2009-04-01

This study aimed to: 1) obtain data about occurrence of childhood domestic injuries in Gunma prefecture according to children's age; 2) ascertain parental awareness of injury prevention; and 3) develop ideas for creating concrete strategies of childhood injury prevention. The participants were 551 parents of children living in 14 cities/towns in Gunma prefecture that showed interest in cooperating with this survey. A self-reported questionnaire was handed to parents when they took their children to health check-ups provided by the cities/towns either during the child's first year, at 18 months, or at 3 years. Parents completed the questionnaire asking whether their child had been injured at home during the past year, and if so, they were asked about the type of injury, the cause of injury, and what action they took. We also asked whether the parents took specific injury prevention measures at home. Data were analyzed statistically. The injury experienced most frequently during the first year of life was "fall" (30.8%), followed by "ingestion of a foreign body" (22.7%), and then "choking" (11.5%). For children around the age of 18 months, the most frequently experienced injury was "fall" (41.0%), followed by "burn" (20.3%), and "ingestion of a foreign body" (19.3%). At 3 years, "burn" was reported most frequently (32.3%), followed by "fall" (31.0%), and "choking" (14.5%). Chi2-test revealed significant correlations among the three age groups concerning the rate of burn injury, foreign body ingestion, and drowning. The rate of burn injury was higher at 3 years than at 18 months, and also higher at 18 months as compared to under the age of one. In contrast, the rate of foreign body ingestion was higher under the age of one than at 18 months, and also higher at 18 months as compared to the age of 3 years. Drowning was more common at 18 months and 3 years than under the age of one. As for prevention of domestic injury, investigation of preventive means taken according to type of injury revealed that parents taking any of the measures to prevent an injury were significantly more likely to also take other means to prevent that injury. Characteristics of injury differed according to children's age. Furthermore, it was clarified that parents' performance of injury prevention depends on their awareness of preventive measures.

Symptoms of dysphagia in children with cleft lip and/or palate pre- and post-surgical correction.

PubMed

Freitas, Jordana da Silva; Cardoso, Maria Cristina de Almeida Freitas

2018-03-05

Determine the occurrence of dysphagia symptoms in children with cleft lip and/or palate (CLP) pre- and post-surgical correction. Quantitative observational cross-sectional study. Existence of clef lip and/or palate without association with other syndromes was the study inclusion and/or exclusion criterion. Parents and/or legal guardians responded to a recall questionnaire on the identification of occurrence of coughing, choking, vomiting, and nasal escape pre- and postoperatively and whether these symptoms disappeared after surgical correction. The study was approved by the Research Ethics Committee of the aforementioned Institution under protocol no. 1573164. The sample comprised 23 children with mean age of 48 months, mostly male and with unilateral trans-foramen incisor clefts. Statistically significant difference was observed between the pre- and post-surgical periods regarding the presence of dysphagia symptoms. Surgical treatment of patients with cleft lip and/or palate proved to be a resource to prevent the occurrence of dysphagia symptoms when associated with adequate intervention chronology.

Novice Shooters With Lower Pre-shooting Alpha Power Have Better Performance During Competition in a Virtual Reality Scenario.

PubMed

Pereira, Michael; Argelaguet, Ferran; Millán, José Del R; Lécuyer, Anatole

2018-01-01

Competition changes the environment for athletes. The difficulty of training for such stressful events can lead to the well-known effect of "choking" under pressure, which prevents athletes from performing at their best level. To study the effect of competition on the human brain, we recorded pilot electroencephalography (EEG) data while novice shooters were immersed in a realistic virtual environment representing a shooting range. We found a differential between-subject effect of competition on mu (8-12 Hz) oscillatory activity during aiming; compared to training, the more the subject was able to desynchronize his mu rhythm during competition, the better was his shooting performance. Because this differential effect could not be explained by differences in simple measures of the kinematics and muscular activity, nor by the effect of competition or shooting performance per se , we interpret our results as evidence that mu desynchronization has a positive effect on performance during competition.

CFD Based Prediction of Discharge Coefficient of Sonic Nozzle with Surface Roughness

NASA Astrophysics Data System (ADS)

Bagaskara, Agastya; Agoes Moelyadi, Mochammad

2018-04-01

Due to its simplicity and accuracy, sonic nozzle is widely used in gas flow measurement, gas flow meter calibration standard, and flow control. The nozzle obtains mass flow rate by measuring temperature and pressure in the inlet during choked flow condition and calculate the flow rate using the one-dimensional isentropic flow equation multiplied by a discharge coefficient, which takes into account multiple non-isentropic effects, which causes the reduction in mass flow. Proper determination of discharge coefficient is crucial to ensure the accuracy of mass flow measurement by the nozzle. Available analytical solution for the prediction of discharge coefficient assumes that the nozzle wall is hydraulically smooth which causes disagreement with experimental results. In this paper, the discharge coefficient of sonic nozzle is determined using computational fluid dynamics method by taking into account the roughness of the wall. It is found that the result shows better agreement with the experiment data compared to the analytical result.

Coherency Between Volume Transport in the Antarctic Circumpolar Current and Southern Hemisphere Winds

NASA Astrophysics Data System (ADS)

Makowski, Jessica; Chambers, Don; Bonin, Jennifer

2013-04-01

Previous studies have suggested that ocean bottom pressure (OBP) can be used to measure the transport variability of the Antarctic Circumpolar Current (ACC). The OBP observations from the Gravity Recovery and Climate Experiment (GRACE) will be used to calculate transport along the 150°E longitude choke point, between Antarctica and Australia. We will examine whether zonally averaged wind stress, wind stress curl, or local zonal winds are more coherent with zonal mass transport variability. Preliminary studies suggest that seasonal variation in transport across 150°E is more correlated with winds along and north of the northern front of the ACC: the Sub Tropical front (STF). It also appears that interannual variations in transport along 150°E are related to wind variations south of the STF and centered south of the Sub Antarctic Front (SAF). We have observed a strong anti-correlation across the SAF, in the Indian Ocean, which suggests wind stress curl may also be responsible for transport variations. Preliminary results will be presented.

Feeding Problems and Their Underlying Mechanisms in the Esophageal Atresia–Tracheoesophageal Fistula Patient

PubMed Central

Mahoney, Lisa; Rosen, Rachel

2017-01-01

Feeding difficulties such as dysphagia, coughing, choking, or vomiting during meals, slow eating, oral aversion, food refusal, and stressful mealtimes are common in children with repaired esophageal atresia (EA) and the reasons for this are often multifactorial. The aim of this review is to describe the possible underlying mechanisms contributing to feeding difficulties in patients with EA and approaches to management. Underlying mechanisms for these feeding difficulties include esophageal dysphagia, oropharyngeal dysphagia and aspiration, and aversions related to prolonged gastrostomy tube feeding. The initial diagnostic evaluation for feeding difficulties in a patient with EA may involve an esophagram, videofluoroscopic imaging or fiberoptic endoscopic evaluation during swallowing, upper endoscopy with biopsies, pH-impedance testing, and/or esophageal motility studies. The main goal of management is to reduce the factors contributing to feeding difficulties and may include reducing esophageal stasis, maximizing reflux therapies, treating underlying lung disease, dilating strictures, and altering feeding methods, routes, or schedules. PMID:28620597

Suspected paradoxical undressing in a homicide case.

PubMed

Kettner, Mattias; Schnabel, Axel; Ramsthaler, Frank

2012-12-01

Paradoxical undressing is a phenomenon associated with fatalities due to severe hypothermia, which is characterized by the act of active undressing, despite low ambient temperatures, as a consequence of peripheral vasodilation. A 51-year-old man was found lying naked and inanimate on a road. Articles of his clothing were scattered in surrounding bushes. A nearby handrail showed a partially washed away bloodstain pattern. A forensic autopsy was used to distinguish whether death was due to a hypothermic fatality or whether the deceased was a victim of an accident or homicide. Medicolegal autopsy revealed craniofacial dissociation with injuries to the thorax and extremities and established choking/asphyxia due to deep aspiration of blood in combination with external blood loss as the cause of death. In the absence of hypothermia-related signs and toxicological findings the case was considered to be a homicide. Police investigation led to the conviction of a man who confessed to having kicked and hit the victim and forced him to take off his clothes in a humiliation-related scenario.

STOLAND

NASA Technical Reports Server (NTRS)

Grgurich, J.; Bradbury, P.

1976-01-01

The STOLAND system includes air data, navigation, guidance, flight director (including a throttle flight director on the Augmentor Wing), 3-axis autopilot and autothrottle functions. The 3-axis autopilot and autothrottle control through parallel electric servos on both aircraft and on the augmentor wing, the system also interfaces with three electrohydraulic series actuators which drive the roll control surfaces, elevator and rudder. The system incorporates automatic configuration control of the flaps and nozzles on the augmentor wing and of the flaps on the Twin Otter. Interfaces are also provided to control the wing flap chokes on the Augmentor Wing and the spoilers on the Twin Otter. The STOLAND system has all the capabilities of a conventional integrated avionics system. Aircraft stabilization is provided in pitch, roll and yaw including control wheel steering in pitch and roll. The basic modes include altitude hold and select, indicated airspeed hold and select, flight path angle hold and select, and heading hold and select. The system can couple to TACAN and VOR/DME navaids for conventional radial flying.

Stress and human spirituality 2000: at the cross roads of physics and metaphysics.

PubMed

Seaward, B L

2000-12-01

Although stress is defined as a perceived threat, the implications of stress go well beyond physical well-being. In the words of Carl Jung, "Every crisis is a spiritual crisis." Western science, so strongly influenced by the Cartesian Principle of Reductionism, has ignored the essence and significance of human spirituality in the health and healing process. Holistic healing honors the integration, balance, and harmony of mind, body, spirit, and emotions, where the whole is greater than the sum of the parts. Stress (unresolved issues of anger and fear) chokes the human spirit, the life force of human energy, which ultimately affects the physical body. From the perspectives of both physics and metaphysics, stress is a disruption in the state of coherence between the layers of consciousness in the human energy field. The emerging paradigm of health reunites mind, body, and spirit, and considers health as a function of coherence among the energy levels of these components.

Analysis of a New Rocket-Based Combined-Cycle Engine Concept at Low Speed

NASA Technical Reports Server (NTRS)

Yungster, S.; Trefny, C. J.

1999-01-01

An analysis of the Independent Ramjet Stream (IRS) cycle is presented. The IRS cycle is a variation of the conventional ejector-Ramjet, and is used at low speed in a rocket-based combined-cycle (RBCC) propulsion system. In this new cycle, complete mixing between the rocket and ramjet streams is not required, and a single rocket chamber can be used without a long mixing duct. Furthermore, this concept allows flexibility in controlling the thermal choke process. The resulting propulsion system is intended to be simpler, more robust, and lighter than an ejector-ramjet. The performance characteristics of the IRS cycle are analyzed for a new single-stage-to-orbit (SSTO) launch vehicle concept, known as "Trailblazer." The study is based on a quasi-one-dimensional model of the rocket and air streams at speeds ranging from lift-off to Mach 3. The numerical formulation is described in detail. A performance comparison between the IRS and ejector-ramjet cycles is also presented.

Late complication of open inguinal hernia repair: small bowel obstruction caused by intraperitoneal mesh migration.

PubMed

Ferrone, Roberto; Scarone, Pier Carlo; Natalini, Gianni

2003-09-01

We describe a case of small bowel obstruction due to prosthetic mesh migration. A 67-year-old male, who had undergone prosthetic repair of inguinal hernia 3 years before, was admitted for a mechanical small bowel obstruction. Laparotomy revealed the penultimate ileal loop choked by an adhesion drawing it towards a polypropylene mesh, firmly attached to the parietal peritoneum of the inguinal region. The intestinal loop was released; the mesh was embedded deep with continuous whip suture after folding the parietal peritoneum. The patient was dismissed on the 11th postoperative day surgically healed. The "tension-free" technique is undoubtedly the gold standard for hernia repair. However, it is not free of complications, mostly due to technical errors, of which the surgeon must be aware, both when he is responsible for correcting defects in the wall, as well as when he has to face an occlusion in a patient who has undergone plastic surgery for inguinal hernia.

Performance of Compressor of XJ-41-V Turbojet Engine. 4; Performance Analysis Over Range of Compressor Speeds from 5000 to 10,000 RPM

NASA Technical Reports Server (NTRS)

Creagh, John W. R.; Ginsburg, Ambrose

1948-01-01

An investigation of the XJ-41-V turbojet-engine compressor was conducted to determine the performance of the compressor and to obtain fundamental information on the aerodynamic problems associated with large centrifugal-type compressors. The results of the research conducted on the original compressor indicated the compressor would not meet the desired engine-design air-flow requirements because of an air-flow restriction in the vaned collector. The compressor air-flow choking point occurred near the entrance to the vaned-collector passage and was instigated by a poor mass-flow distribution at the vane entrance and from relatively large negative angles of attack of the air stream along the entrance edges of the vanes at the outer passage wall and large positive angles of attack at the inner passage wall. As a result of the analysis, a design change of the vaned collector entrance is recommended for improving the maximum flow capacity of the compressor.

Component Performance Investigation of J71 Experimental Turbine I : Over-all Performance with 97-percent-design Stator Areas

NASA Technical Reports Server (NTRS)

Schum, Harold J; Davison, Elmer H

1956-01-01

The over-all component performance characteristics of a J71 experimental three-stage turbine with 97 percent design stator areas were determined over a range of speed and pressure ratio at inlet-air conditions of approximately 35 inches of mercury absolute and 700 degrees R. The turbine break internal efficiency at design operating conditions was 0.877; the maximum efficiency of 0.886 occurred at a pressure ratio of 4.0 at 120 percent of design equivalent rotor speed. In general, the turbine yielded a wide range of efficient operation, permitting flexibility in the choice of different modes of engine operation. Limiting blade loading of the third rotor was approached but not obtained over the range of conditions investigated herein. At the design operating point, the turbine equivalent weight flow was approximately 105 percent of design. Choking of the third-rotor blades occurred at design speed and an over-all pressure ratio of 4.2.

High resolution LiDAR measurements reveal fine internal structure and variability of sediment-carrying coastal plume

NASA Astrophysics Data System (ADS)

Zavialov, P. O.; Pelevin, V. V.; Belyaev, N. A.; Izhitskiy, A. S.; Konovalov, B. V.; Krementskiy, V. V.; Goncharenko, I. V.; Osadchiev, A. A.; Soloviev, D. M.; Garcia, C. A. E.; Pereira, E. S.; Sartorato, L.; Moller, O. O.

2018-05-01

We report results of a field survey conducted in the buoyant, sediment-carrying coastal plume generated by the discharge from the Patos Lagoon, the World's largest choked lagoon. The concentration of total suspended matter (TSM) and organic matter (as represented by total organic carbon, TOC) were mapped using an ultraviolet fluorescent LiDAR, which allowed for extensive data coverage (total of 79,387 simultaneous determinations of TSM and TOC) during 3 consecutive days. These observations were accompanied by hydrographic measurements from the ship and at a mooring station. We first describe synoptic variability of the plume, which responded energetically to wind forcing. We then analyze the TSM, TOC and hydrographic data jointly and develop a simple approach to estimate the rates of suspended matter removal from the upper layer due to gravitational settling and turbulent mixing based on relative changes in TSM and TOC concentrations. Four distinct regions within the plume exhibiting different dynamics of suspended and dissolved constituents were identified on this basis.

Ceramic micro-injection molded nozzles for serial femtosecond crystallography sample delivery

NASA Astrophysics Data System (ADS)

Beyerlein, K. R.; Adriano, L.; Heymann, M.; Kirian, R.; Knoška, J.; Wilde, F.; Chapman, H. N.; Bajt, S.

2015-12-01

Serial femtosecond crystallography (SFX) using X-ray Free-Electron Lasers (XFELs) allows for room temperature protein structure determination without evidence of conventional radiation damage. In this method, a liquid suspension of protein microcrystals can be delivered to the X-ray beam in vacuum as a micro-jet, which replenishes the crystals at a rate that exceeds the current XFEL pulse repetition rate. Gas dynamic virtual nozzles produce the required micrometer-sized streams by the focusing action of a coaxial sheath gas and have been shown to be effective for SFX experiments. Here, we describe the design and characterization of such nozzles assembled from ceramic micro-injection molded outer gas-focusing capillaries. Trends of the emitted jet diameter and jet length as a function of supplied liquid and gas flow rates are measured by a fast imaging system. The observed trends are explained by derived relationships considering choked gas flow and liquid flow conservation. Finally, the performance of these nozzles in a SFX experiment is presented, including an analysis of the observed background.

Volcanic gas

USGS Publications Warehouse

McGee, Kenneth A.; Gerlach, Terrance M.

1995-01-01

In Roman mythology, Vulcan, the god of fire, was said to have made tools and weapons for the other gods in his workshop at Olympus. Throughout history, volcanoes have frequently been identified with Vulcan and other mythological figures. Scientists now know that the “smoke" from volcanoes, once attributed by poets to be from Vulcan’s forge, is actually volcanic gas naturally released from both active and many inactive volcanoes. The molten rock, or magma, that lies beneath volcanoes and fuels eruptions, contains abundant gases that are released to the surface before, during, and after eruptions. These gases range from relatively benign low-temperature steam to thick hot clouds of choking sulfurous fume jetting from the earth. Water vapor is typically the most abundant volcanic gas, followed by carbon dioxide and sulfur dioxide. Other volcanic gases are hydrogen sulfide, hydrochloric acid, hydrogen, carbon monoxide, hydrofluoric acid, and other trace gases and volatile metals. The concentrations of these gas species can vary considerably from one volcano to the next.

The Kra Isthmus Canal: A New Strategic Solution for China's Energy Consumption Scenario?

PubMed

Lau, Cheng Yong; Lee, Jason Wai Chow

2016-01-01

This paper is a conceptual study that examines the viability of the construction of the Kra Isthmus within the context of the five dimensions of megaproject success of Sovacool and Cooper (The governance of energy megaprojects: politics, hubris, and energy security, 2013)-social (governance), technological (systems), democratic (politics), externalities (economics, ecology), and risks assessments (accountability), and its possible impact on China's strategic energy supply chain. One of the objectives of this study is also to discuss the current impacts, perceived benefits, and risks of China's dependence on its multinational and transnational pipelines. China could see the construction of Kra Canal as an alternative option for its strategic sourcing activities especially crude oil and gas at much lower costs. The megaproject would become a passageway that connects the Indian Ocean, Andaman Sea, and the Gulf of Siam at the choke point of Isthmus region in Thailand. However, this megaproject could also trigger the internal conflicts of Thailand, and affect the ASEAN countries' political and economic relationships.

A hierarchy for modeling high speed propulsion systems

NASA Technical Reports Server (NTRS)

Hartley, Tom T.; Deabreu, Alex

1991-01-01

General research efforts on reduced order propulsion models for control systems design are overviewed. Methods for modeling high speed propulsion systems are discussed including internal flow propulsion systems that do not contain rotating machinery, such as inlets, ramjets, and scramjets. The discussion is separated into four areas: (1) computational fluid dynamics models for the entire nonlinear system or high order nonlinear models; (2) high order linearized models derived from fundamental physics; (3) low order linear models obtained from the other high order models; and (4) low order nonlinear models (order here refers to the number of dynamic states). Included in the discussion are any special considerations based on the relevant control system designs. The methods discussed are for the quasi-one-dimensional Euler equations of gasdynamic flow. The essential nonlinear features represented are large amplitude nonlinear waves, including moving normal shocks, hammershocks, simple subsonic combustion via heat addition, temperature dependent gases, detonations, and thermal choking. The report also contains a comprehensive list of papers and theses generated by this grant.

Flow and acoustic properties of low Reynolds number supersonic underexpanded jets

NASA Technical Reports Server (NTRS)

Hu, T. F.; Mclaughlin, D. K.

1981-01-01

Flow and acoustic measurements are made of cold model jets exhausting from a choked nozzle at pressure conditions corresponding to those of Mach 1.4 and 2.1 jets to investigate noise production properties of underexpanded supersonic jets. Mean flow measurements are made using pitot and static pressure probes, with flow fluctuation measurements made with a hot-wire probe and acoustic measurements made with a transversing microphone. Two convergent nozzles with exit diameters of 7.0 and 7.9 mm are used with an exciter consisting of a 0.8 mm tungsten electrode positioned 2 mm from the exit. Shock structure is observed as having a significant effect on the development of the flow field, while large-scale instabilities have higher growth rates in the shock containing underexpanded jets. The role of the asymmetric n = + or - 1 sinusoidal instability is clarified, and results suggest that the broadband shock associated noise of conventional high Reynolds number jets is not related to large-scale jet instability.

Simulated sensitivity of the tropical cyclone eyewall replacement cycle to the ambient temperature profile

NASA Astrophysics Data System (ADS)

Ma, Xulin; He, Jie; Ge, Xuyang

2017-09-01

In this study, the impacts of the environmental temperature profile on the tropical cyclone eyewall replacement cycle are examined using idealized numerical simulations. It is found that the environmental thermal condition can greatly affect the formation and structure of a secondary eyewall and the intensity change during the eyewall replacement cycle. Simulation with a warmer thermal profile produces a larger moat and a prolonged eyewall replacement cycle. It is revealed that the enhanced static stability greatly suppresses convection, and thus causes slow secondary eyewall formation. The possible processes influencing the decay of inner eyewall convection are investigated. It is revealed that the demise of the inner eyewall is related to a choking effect associated with outer eyewall convection, the radial distribution of moist entropy fluxes within the moat region, the enhanced static stability in the inner-core region, and the interaction between the inner and outer eyewalls due to the barotropic instability. This study motivates further research into how environmental conditions influence tropical cyclone dynamics and thermodynamics.

Heavy metal accumulation and growth of seedlings of five forest species as influenced by soil cadmium level

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelly, J.M.; Parker, G.R.; McFee, W.W.

1979-07-01

White pine (Pinus strobus L.), loblolly pine (P. taeda L.), yellow poplar (Liriodendron tulipifera L.), yellow birch (Betula alleghaniensis Britt.), and choke cherry (Prunus virginiana L.) were grown from seeds in the greenhouse for 17 weeks. Plainfield fine sand, with pretreatment cadmium, lead, copper, and zinc concentrations of 0.6, 11.4, 2.0, and 20.6 ppM, respectively, was used as the growth medium. This soil was amended with CdCl/sub 2/ to produce cadmium addition levels of 0, 15, and 100 ppM. Shoot elongation and root and shoot dry weights were reduced with increasing levels of soil cadmium. All species exhibited increased cadmiummore » content in roots and shoots in response to increased soil cadmium levels; however, content varied according to species. Root and shoot accumulations of lead, copper, and zinc also varied with species as well as cadmium concentration in the soil.« less

Experimental aerodynamic performance of advanced 40 deg-swept 10-blade propeller model at Mach 0.6 to 0.85

NASA Technical Reports Server (NTRS)

Mitchell, Glenn A.

1988-01-01

A propeller designated as SR-6, designed with 40 deg of sweep and 10 blades to cruise at Mach 0.8 at an altitude of 10.7 km (35,000 ft), was tested in the NASA Lewis Research Center's 8- by 6-Foot Wind Tunnel. This propeller was one of a series of advanced single rotation propeller models designed and tested as part of the NASA Advanced Turboprop Project. Design-point net efficiency was almost constant to Mach 0.75 but fell above this speed more rapidly than that of any previously tested advanced propeller. Alternative spinners that further reduced the near-hub interblade Mach numbers and relieved the observed hub choking improved performance above Mach 0.75. One spinner attained estimated SR-6 Design-point net deficiencies of 80.6 percent at Mach 0.75 and 79.2 percent at Mach 0.8, higher than the measured performance of any previously tested advanced single-rotation propeller at these speeds.

The Kra Isthmus Canal: A New Strategic Solution for China's Energy Consumption Scenario?

NASA Astrophysics Data System (ADS)

Lau, Cheng Yong; Lee, Jason Wai Chow

2016-01-01

This paper is a conceptual study that examines the viability of the construction of the Kra Isthmus within the context of the five dimensions of megaproject success of Sovacool and Cooper (The governance of energy megaprojects: politics, hubris, and energy security, 2013)—social (governance), technological (systems), democratic (politics), externalities (economics, ecology), and risks assessments (accountability), and its possible impact on China's strategic energy supply chain. One of the objectives of this study is also to discuss the current impacts, perceived benefits, and risks of China's dependence on its multinational and transnational pipelines. China could see the construction of Kra Canal as an alternative option for its strategic sourcing activities especially crude oil and gas at much lower costs. The megaproject would become a passageway that connects the Indian Ocean, Andaman Sea, and the Gulf of Siam at the choke point of Isthmus region in Thailand. However, this megaproject could also trigger the internal conflicts of Thailand, and affect the ASEAN countries' political and economic relationships.