49 CFR 178.345-10 - Pressure relief.
Code of Federal Regulations, 2012 CFR
2012-10-01
... cargo tank must be provided with a primary pressure relief system consisting of one or more reclosing... parallel with the primary pressure relief system may be used to augment the total venting capacity of the cargo tank. Non-reclosing pressure relief devices are not authorized in any cargo tank except when in...
49 CFR 178.345-10 - Pressure relief.
Code of Federal Regulations, 2011 CFR
2011-10-01
... cargo tank must be provided with a primary pressure relief system consisting of one or more reclosing... parallel with the primary pressure relief system may be used to augment the total venting capacity of the cargo tank. Non-reclosing pressure relief devices are not authorized in any cargo tank except when in...
49 CFR 178.345-10 - Pressure relief.
Code of Federal Regulations, 2014 CFR
2014-10-01
... cargo tank must be provided with a primary pressure relief system consisting of one or more reclosing... parallel with the primary pressure relief system may be used to augment the total venting capacity of the cargo tank. Non-reclosing pressure relief devices are not authorized in any cargo tank except when in...
49 CFR 178.345-10 - Pressure relief.
Code of Federal Regulations, 2013 CFR
2013-10-01
... cargo tank must be provided with a primary pressure relief system consisting of one or more reclosing... parallel with the primary pressure relief system may be used to augment the total venting capacity of the cargo tank. Non-reclosing pressure relief devices are not authorized in any cargo tank except when in...
McDermott, D.J.; Schrader, K.J.; Schulz, T.L.
1994-05-03
The effects of steam generator tube ruptures in a pressurized water reactor are mitigated by reducing the pressure in the primary loop by diverting reactor coolant through the heat exchanger of a passive heat removal system immersed in the in containment refueling water storage tank in response to a high feed water level in the steam generator. Reactor coolant inventory is maintained by also in response to high steam generator level introducing coolant into the primary loop from core make-up tanks at the pressure in the reactor coolant system pressurizer. The high steam generator level is also used to isolate the start-up feed water system and the chemical and volume control system to prevent flooding into the steam header. 2 figures.
McDermott, Daniel J.; Schrader, Kenneth J.; Schulz, Terry L.
1994-01-01
The effects of steam generator tube ruptures in a pressurized water reactor are mitigated by reducing the pressure in the primary loop by diverting reactor coolant through the heat exchanger of a passive heat removal system immersed in the in containment refueling water storage tank in response to a high feed water level in the steam generator. Reactor coolant inventory is maintained by also in response to high steam generator level introducing coolant into the primary loop from core make-up tanks at the pressure in the reactor coolant system pressurizer. The high steam generator level is also used to isolate the start-up feed water system and the chemical and volume control system to prevent flooding into the steam header. 2 figures.
Esselman, W.H.; Kaplan, G.M.
1961-06-20
The control of pressure in pressurized liquid systems, especially a pressurized liquid reactor system, may be achieved by providing a bias circuit or loop across a closed loop having a flow restriction means in the form of an orifice, a storage tank, and a pump connected in series. The subject invention is advantageously utilized where control of a reactor can be achieved by response to the temperature and pressure of the primary cooling system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pahari, S.; Hajela, S.; Rammohan, H. P.
2012-07-01
700 MWe Indian Pressurized Heavy Water Reactor (IPHWR) is horizontal channel type reactor with partial boiling at channel outlet. Due to boiling, it has a large volume of vapor present in the primary loops. It has two primary loops connected with the help of pressurizer surge line. The pressurizer has a large capacity and is partly filled by liquid and partly by vapor. Large vapor volume improves compressibility of the system. During turbine trip or load rejection, pressure builds up in Steam Generator (SG). This leads to pressurization of Primary Heat Transport System (PHTS). To control pressurization of SG andmore » PHTS, around 70% of the steam generated in SG is dumped into the condenser by opening Condenser Steam Dump Valves (CSDVs) and rest of the steam is released to the atmosphere by opening Atmospheric Steam Discharge Valves (ASDVs) immediately after sensing the event. This is accomplished by adding anticipatory signal to the output of SG pressure controller. Anticipatory signal is proportional to the thermal power of reactor and the proportionality constant is set so that SG pressure controller's output jacks up to ASDV opening range when operating at 100% FP. To simulate this behavior for 700 MWe IPHWR, Primary and secondary heat transport system is modeled. SG pressure control and other process control program have also been modeled to capture overall plant dynamics. Analysis has been carried out with 3-D neutron kinetics coupled thermal hydraulic computer code ATMIKA.T to evaluate the effect of the anticipatory signal on PHT pressure and over all plant dynamics during turbine trip in 700 MWe IPHWR. This paper brings out the results of the analysis with and without considering anticipatory signal in SG pressure control program during turbine trip. (authors)« less
Introducing the Pressure-Sensing Palatograph--The Next Frontier in Electropalatography
ERIC Educational Resources Information Center
Murdoch, Bruce; Goozee, Justine; Veidt, Martin; Scott, Dion; Meyers, Ian
2004-01-01
Primary Objective. To extend the capabilities of current electropalatography (EPG) systems by developing a pressure-sensing EPG system. An initial trial of a prototype pressure-sensing palate will be presented. Research Design. The processes involved in designing the pressure sensors are outlined, with Hall effect transistors being selected. These…
Pressure Systems Energy Release Protection (Gas Pressurized Systems)
NASA Technical Reports Server (NTRS)
Brown, S. J. (Editor)
1986-01-01
A survey of studies into hazards associated with closed or pressurized system rupture and preliminary guidelines for the performance design of primary, secondary, and protective receptors of these hazards are provided. The hazards discussed in the survey are: blast, fragments, ground motion, heat radiation, biological, and chemical. Performance guidelines for receptors are limited to pressurized systems that contain inert gas. The performance guidelines for protection against the remaining unaddressed degenerative hazards are to be covered in another study.
Simulation of a main steam line break with steam generator tube rupture using trace
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gallardo, S.; Querol, A.; Verdu, G.
A simulation of the OECD/NEA ROSA-2 Project Test 5 was made with the thermal-hydraulic code TRACE5. Test 5 performed in the Large Scale Test Facility (LSTF) reproduced a Main Steam Line Break (MSLB) with a Steam Generator Tube Rupture (SGTR) in a Pressurized Water Reactor (PWR). The result of these simultaneous breaks is a depressurization in the secondary and primary system in loop B because both systems are connected through the SGTR. Good approximation was obtained between TRACE5 results and experimental data. TRACE5 reproduces qualitatively the phenomena that occur in this transient: primary pressure falls after the break, stagnation ofmore » the pressure after the opening of the relief valve of the intact steam generator, the pressure falls after the two openings of the PORV and the recovery of the liquid level in the pressurizer after each closure of the PORV. Furthermore, a sensitivity analysis has been performed to know the effect of varying the High Pressure Injection (HPI) flow rate in both loops on the system pressures evolution. (authors)« less
Coordinating Mental Health Care across Primary Care and Schools: ADHD as a Case Example
ERIC Educational Resources Information Center
Power, Thomas J.; Blum, Nathan J.; Guevara, James P.; Jones, Heather A.; Leslie, Laurel K.
2013-01-01
Although primary care practices and schools are major venues for the delivery of mental health services to children, these systems are disconnected, contributing to fragmentation in service delivery. This paper describes barriers to collaboration across the primary care and school systems, including administrative and fiscal pressures, conceptual…
Wostyn, Peter; Killer, Hanspeter Esriel; De Deyn, Peter Paul
2017-07-01
The underlying pathophysiology of primary open-angle glaucoma remains unclear, but the lamina cribrosa seems to be the primary site of injury, and raised intraocular pressure is a major risk factor. In recent years, a decreased intracranial pressure, leading to an abnormally high trans-lamina cribrosa pressure difference, has gained interest as a new risk factor for glaucoma. New research now lends support to the hypothesis that a paravascular transport system is present in the eye analogous to the recently discovered 'glymphatic system' in the brain, which is a functional waste clearance pathway that promotes elimination of interstitial solutes, including β-amyloid, from the brain along paravascular channels. Given that β-amyloid has been reported to increase by chronic elevation of intraocular pressure in glaucomatous animal models and to cause retinal ganglion cell death, the discovery of a paravascular clearance system in the eye may provide powerful new insights into the pathophysiology of primary open-angle glaucoma. In this review, we provide a new conceptual framework for understanding the pathogenesis of primary open-angle glaucoma, present supporting preliminary data from our own post-mortem study and hypothesize that the disease may result from restriction of normal glymphatic flow at the level of the lamina cribrosa owing to a low intracranial pressure and/or a high trans-lamina cribrosa pressure gradient. If confirmed, this viewpoint could offer new perspectives for the development of novel diagnostic and therapeutic strategies for this devastating disorder. © 2017 Royal Australian and New Zealand College of Ophthalmologists.
Recent progress in high pressure metrology in Europe
NASA Astrophysics Data System (ADS)
Sabuga, Wladimir; Pražák, Dominik; Rabault, Thierry
2014-08-01
Five European national metrology institutes in collaboration with a university, a research institute and five industrial companies are working on a joint research project within a framework of the European Metrology Research Programme aimed at development of 1.6 GPa primary and 1.5 GPa transfer pressure standards. Two primary pressure standards were realised as pressure-measuring multipliers, each consisting of a low pressure and a high pressure (HP) piston-cylinder assembly (PCA). A special design of the HP PCAs was developed in which a tungsten carbide cylinder is supported by two thermally shrunk steel sleeves and, additionally, by jacket pressure applied to the outside of the outer sleeve. Stress-strain finite element analysis (FEA) was performed to predict behaviour of the multipliers and a pressure generation system. With FEA, the pressure distortion coefficient was determined, taking into account irregularities of the piston-cylinder gap. Transfer pressure standards up to 1.5 GPa are developed on the basis of modern 1.5 GPa pressure transducers. This project shall solve a discrepancy between the growing needs of the industry demanding precise traceable calibrations of the high pressure transducers and the absence of adequate primary standards for pressures higher than 1 GPa in the European Union today.
NASA Technical Reports Server (NTRS)
Nelson, D. P.
1981-01-01
A graphical presentation of the aerodynamic data acquired during coannular nozzle performance wind tunnel tests is given. The graphical data consist of plots of nozzle gross thrust coefficient, fan nozzle discharge coefficient, and primary nozzle discharge coefficient. Normalized model component static pressure distributions are presented as a function of primary total pressure, fan total pressure, and ambient static pressure for selected operating conditions. In addition, the supersonic cruise configuration data include plots of nozzle efficiency and secondary-to-fan total pressure pumping characteristics. Supersonic and subsonic cruise data are given.
Research on pressure control of pressurizer in pressurized water reactor nuclear power plant
NASA Astrophysics Data System (ADS)
Dai, Ling; Yang, Xuhong; Liu, Gang; Ye, Jianhua; Qian, Hong; Xue, Yang
2010-07-01
Pressurizer is one of the most important components in the nuclear reactor system. Its function is to keep the pressure of the primary circuit. It can prevent shutdown of the system from the reactor accident under the normal transient state while keeping the setting value in the normal run-time. This paper is mainly research on the pressure system which is running in the Daya Bay Nuclear Power Plant. A conventional PID controller and a fuzzy controller are designed through analyzing the dynamic characteristics and calculating the transfer function. Then a fuzzy PID controller is designed by analyzing the results of two controllers. The fuzzy PID controller achieves the optimal control system finally.
Sour pressure swing adsorption process
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhadra, Shubhra Jyoti; Wright, Andrew David; Hufton, Jeffrey Raymond
Methods and apparatuses for separating CO.sub.2 and sulfur-containing compounds from a synthesis gas obtained from gasification of a carbonaceous feedstock. The primary separating steps are performed using a sour pressure swing adsorption (SPSA) system, followed by an acid gas enrichment system and a sulfur removal unit. The SPSA system includes multiple pressure equalization steps and a rinse step using a rinse gas that is supplied from a source other than directly from one of the adsorber beds of the SPSA system.
High Prevalence of Insecure Attachment in Patients with Primary Hypertension
Balint, Elisabeth M.; Gander, Manuela; Pokorny, Dan; Funk, Alexandra; Waller, Christiane; Buchheim, Anna
2016-01-01
Hypertension is a major cardiovascular (CV) risk factor and is predicted by heightened CV reactivity to stress in healthy individuals. Patients with hypertension also show an altered stress response, while insecure attachment is linked to a heightened stress reactivity as well. This is the first study aiming to assess attachment representations in patients with primary hypertension and to investigate their CV responses when their attachment system is activated. We studied 50 patients (38 men, 12 women) with primary hypertension. The Adult Attachment Projective Picture System (AAP), a widely used and validated interview, was performed to measure the patients' attachment representations, and to activate their attachment system. Blood pressure and heart rate were measured after 10 min at rest prior to and directly after the AAP interview. Mood and state anxiety were assessed using the Multidimensional Mood State Questionnaire (MDBF) and the State Trait Anxiety Inventory-State (STAI-S) before and after the experiment. The prevalence of insecure attachment (dismissing, preoccupied, unresolved) in hypertensive patients was predominant (88%), while in non-clinical populations, only about 50% of individuals had insecure attachment patterns. Blood pressure (p < 0.001), heart rate (p = 0.016), and rate pressure product (p < 0.001) significantly increased in response to the attachment interview. Secure attached patients showed the highest rise in systolic blood pressure (p = 0.020) and the lowest heart rate compared to the other attachment groups (p = 0.043). However, attachment representation showed no significant group or interaction effects on diastolic blood pressure (DBP) and rate pressure product. Insecure attachment was highly over-represented in our sample of patients with primary hypertension. Additionally, a robust CV response to the attachment-activating stimulus was observed. Our data suggest that insecure attachment is significantly linked to primary hypertension, which implies the need for further investigations to evaluate attachment insecurity as a possible risk factor for hypertension. PMID:27536255
Designing and Constructing an Optical Monitoring System of Blood Supply to Tissues under Pressure.
Hadi, Akbari; Amin, Younessi Heravi Mohammad
2012-04-01
Reduced blood flow due to obstruction is in most cases a primary factor in pressure ulcer formation and creation of bedsores. The aim of this study is to design and manufacture a care system for tissue under pressure, based on variations in blood flow at different depths of tissue. In the manufacture of the system two infrared light transmitters and receivers were located between 5 and 10 mm depth to measure the flow of blood at different in the under- pressure heel tissue. In addition, blood flow was evaluated in an unloaded and loaded condition, with 30 mmHg and 60.0 mmHg. A total of 15 people participated with a mean age of 50. Of these 15; 9 (60%) were men and 6 (40%) were women. Primary measurement results showed different individual differences in variation of blood flow in the tissue. To study signal amplitude changes significantly influenced by external pressure the PPG, P-value was measured. It was noted that there were significant changes in PPG signal amplitude during loading both pressures of 30 and 60 mmHg. Further development of this system would be possible with the use of a more flexible probe and by using a stronger optical receiver and transmitter to access more depth.
Development Specification for the Portable Life Support System (PLSS) Thermal Loop Pump
NASA Technical Reports Server (NTRS)
Anchondo, Ian; Campbell, Colin
2017-01-01
The AEMU Thermal Loop Pump Development Specification establishes the requirements for design, performance, and testing of the Water Pump as part of the Thermal System of the Advanced Portable Life Support System (PLSS). It is envisioned that the Thermal Loop Pump is a positive displacement pump that provides a repeatable volume of flow against a given range of back-pressures provided by the various applications. The intention is to operate the pump at a fixed speed for the given application. The primary system is made up of two identical and redundant pumps of which only one is in operation at given time. The Auxiliary Loop Pump is an identical pump design to the primary pumps but is operated at half the flow rate. Inlet positive pressure to the pumps is provided by the upstream Flexible Supply Assembly (FSA-431 and FSA-531) which are physically located inside the suit volume and pressurized by suit pressure. An integrated relief valve, placed in parallel to the pump's inlet and outlet protects the pump and loop from over-pressurization. An integrated course filter is placed upstream of the pump's inlet to provide filtration and prevent potential debris from damaging the pump.
40 CFR 63.1657 - Monitoring requirements.
Code of Federal Regulations, 2011 CFR
2011-07-01
... pressure drop across each baghouse cell, or across the baghouse if it is not possible to monitor each cell individually, to ensure the pressure drop is within the normal operating range identified in the baghouse... detection system if the furnace primary and/or tapping emissions are ducted to a negative pressure baghouse...
A novel pressure-driven piezodispenser for nanoliter volumes.
McGuire, Shawn; Fisher, Charles; Holl, Mark; Meldrum, Deirdre
2008-08-01
A successful dispensing device has been built for use in biotechnology applications requiring nanoliter volume liquid transfer. Air pressure is used as the primary driving force and is controlled via a high speed miniature solenoid valve as opposed to many existing systems that use a valve in line with constantly pressurized fluid to start and stop the dispensing action. This automated pressure-driven system is used to improve a typical piezodriven microdispenser. The resulting system is much less prone to failures resulting from air entrainment and can dispense much higher viscosity fluids than the microdispenser alone.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weber, P.; Umminger, K.J.; Schoen, B.
1995-09-01
The thermal hydraulic behavior of a PWR during beyond-design-basis accident scenarios is of vital interest for the verification and optimization of accident management procedures. Within the scope of the German reactor safety research program experiments were performed in the volumetrically scaled PKL 111 test facility by Siemens/KWU. This highly instrumented test rig simulates a KWU-design PWR (1300 MWe). In particular, the latest tests performed related to a SBLOCA with additional system failures, e.g. nitrogen entering the primary system. In the case of a SBLOCA, it is the goal of the operator to put the plant in a condition where themore » decay heat can be removed first using the low pressure emergency core cooling system and then the residual heat removal system. The experimental investigation presented assumed the following beyond-design-basis accident conditions: 0.5% break in a cold leg, 2 of 4 steam generators (SGs) isolated on the secondary side (feedwater- and steam line-valves closed), filled with steam on the primary side, cooldown of the primary system using the remaining two steam generators, high pressure injection system only in the two loops with intact steam generators, if possible no operator actions to reach the conditions for residual heat removal system activation. Furthermore, it was postulated that 2 of the 4 hot leg accumulators had a reduced initial water inventory (increased nitrogen inventory), allowing nitrogen to enter the primary system at a pressure of 15 bar and nearly preventing the heat transfer in the SGs ({open_quotes}passivating{close_quotes} U-tubes). Due to this the heat transfer regime in the intact steam generators changed remarkably. The primary system showed self-regulating system effects and heat transfer improved again (reflux-condenser mode in the U-tube inlet region).« less
Measuring Pressure Has a New Standard
NASA Technical Reports Server (NTRS)
2002-01-01
The Force-Balanced Piston Gauge (FPG) tests and calibrates instrumentation operating in the low pressure range. The system provides a traceable, primary calibration standard for measuring pressures in the range of near 0 to 15 kPa (2.2 psi) in both gauge and absolute measurement modes. The hardware combines a large area piston-cylinder with a load cell measuring the force resulting from pressures across the piston. The mass of the piston can be tared out, allowing measurement to start from zero. A pressure higher than the measured pressure, which keeps the piston centered, lubricates an innovative conical gap located between the piston and the cylinder, eliminating the need for piston rotation. A pressure controller based on the control of low gas flow automates the pressure control. DHI markets the FPG as an automated primary standard for very low-gauge and absolute pressures. DHI is selling the FPG to high-end metrology laboratories on a case by case basis, with a full commercial release to follow.
Interface requirements for coupling a containment code to a reactor system thermal hydraulic codes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baratta, A.J.
1997-07-01
To perform a complete analysis of a reactor transient, not only the primary system response but the containment response must also be accounted for. Such transients and accidents as a loss of coolant accident in both pressurized water and boiling water reactors and inadvertent operation of safety relief valves all challenge the containment and may influence flows because of containment feedback. More recently, the advanced reactor designs put forth by General Electric and Westinghouse in the US and by Framatome and Seimens in Europe rely on the containment to act as the ultimate heat sink. Techniques used by analysts andmore » engineers to analyze the interaction of the containment and the primary system were usually iterative in nature. Codes such as RELAP or RETRAN were used to analyze the primary system response and CONTAIN or CONTEMPT the containment response. The analysis was performed by first running the system code and representing the containment as a fixed pressure boundary condition. The flows were usually from the primary system to the containment initially and generally under choked conditions. Once the mass flows and timing are determined from the system codes, these conditions were input into the containment code. The resulting pressures and temperatures were then calculated and the containment performance analyzed. The disadvantage of this approach becomes evident when one performs an analysis of a rapid depressurization or a long term accident sequence in which feedback from the containment can occur. For example, in a BWR main steam line break transient, the containment heats up and becomes a source of energy for the primary system. Recent advances in programming and computer technology are available to provide an alternative approach. The author and other researchers have developed linkage codes capable of transferring data between codes at each time step allowing discrete codes to be coupled together.« less
Space nuclear system volume accumulator development (SNAP program)
NASA Technical Reports Server (NTRS)
Whitaker, W. D.; Shimazaki, T. T.
1973-01-01
The engineering, design, and fabrication status of the volume accumulator units to be employed in the NaK primary and secondary coolant loops of the 5-kwe reactor thermoelectric system are described. Three identical VAU's are required - two for the primary coolant loop, and one for the secondary coolant loop. The VAU's utilize nested-formed bellows as the flexing member, are hermetically sealed, provide double containment and utilize a combination of gas pressure force and bellows spring force to obtain the desired pressure regulation of the coolant loops. All parts of the VAU, except the NaK inlet tube, are to be fabricated from Inconel 718.
Hydrocarbon fluid, ejector refrigeration system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kowalski, G.J.; Foster, A.R.
1993-08-31
A refrigeration system is described comprising: a vapor ejector cycle including a working fluid having a property such that entropy of the working fluid when in a saturated vapor state decreases as pressure decreases, the vapor ejector cycle comprising: a condenser located on a common fluid flow path; a diverter located downstream from the condenser for diverting the working fluid into a primary fluid flow path and a secondary fluid flow path parallel to the primary fluid flow path; an evaporator located on the secondary fluid flow path; an expansion device located on the secondary fluid flow path upstream ofmore » the evaporator; a boiler located on the primary fluid flow path parallel to the evaporator for boiling the working fluid, the boiler comprising an axially extending core region having a substantially constant cross sectional area and a porous capillary region surrounding the core region, the core region extending a length sufficient to produce a near sonic velocity saturated vapor; and an ejector having an outlet in fluid communication with the inlet of the condenser and an inlet in fluid communication with the outlet of the evaporator and the outlet of the boiler and in which the flows of the working fluid from the evaporator and the boiler are mixed and the pressure of the working fluid is increased to at least the pressure of the condenser, the ejector inlet, located downstream from the axially extending core region, including a primary nozzle located sufficiently close to the outlet of the boiler to minimize a pressure drop between the boiler and the primary nozzle, the primary nozzle of the ejector including a converging section having an included angle and length preselected to receive the working fluid from the boiler as a near sonic velocity saturated vapor.« less
Kimura, Joe; DaSilva, Karen; Marshall, Richard
2008-02-01
The increasing prevalence of chronic illnesses in the United States requires a fundamental redesign of the primary care delivery system's structure and processes in order to meet the changing needs and expectations of patients. Population management, systems-based practice, and planned chronic illness care are 3 potential processes that can be integrated into primary care and are compatible with the Chronic Care Model. In 2003, Harvard Vanguard Medical Associates, a multispecialty ambulatory physician group practice based in Boston, Massachusetts, began implementing all 3 processes across its primary care practices. From 2004 to 2006, the overall diabetes composite quality measures improved from 51% to 58% for screening (HgA1c x 2, low-density lipoprotein, blood pressure in 12 months) and from 13% to 17% for intermediate outcomes (HgA1c
Failure detection and fault management techniques for flush airdata sensing systems
NASA Technical Reports Server (NTRS)
Whitmore, Stephen A.; Moes, Timothy R.; Leondes, Cornelius T.
1992-01-01
A high-angle-of-attack flush airdata sensing system was installed and flight tested on the F-18 High Alpha Research Vehicle at NASA-Dryden. This system uses a matrix of pressure orifices arranged in concentric circles on the nose of the vehicle to determine angles of attack, angles of sideslip, dynamic pressure, and static pressure as well as other airdata parameters. Results presented use an arrangement of 11 symmetrically distributed ports on the aircraft nose. Experience with this sensing system data indicates that the primary concern for real-time implementation is the detection and management of overall system and individual pressure sensor failures. The multiple port sensing system is more tolerant to small disturbances in the measured pressure data than conventional probe-based intrusive airdata systems. However, under adverse circumstances, large undetected failures in individual pressure ports can result in algorithm divergence and catastrophic failure of the entire system. How system and individual port failures may be detected using chi sq. analysis is shown. Once identified, the effects of failures are eliminated using weighted least squares.
Is public health ready to participate in the transformation of the healthcare system?
Millar, John; Bruce, Ted; Cheng, Siu Mee; Masse, Richard; McKeown, David
2013-01-01
The healthcare system in Canada is undergoing significant transformation in response to three major interrelated pressures: the overall burden of illness is rising, patients are getting poor quality of care and healthcare costs are inexorably rising. One idea to guide this change is to transform the primary care system into a community-based primary healthcare (CBPH) system. This paper discusses, in particular, the readiness of public health to participate in the transformation to a CBPH system. Copyright © 2013 Longwoods Publishing.
CTR Fuel recovery system using regeneration of a molecular sieve drying bed
Folkers, Charles L.
1981-01-01
A primary molecular sieve drying bed is regenerated by circulating a hot inert gas through the heated primary bed to desorb water held on the bed. The inert gas plus water vapor is then cooled and passed through an auxiliary molecular sieve bed which adsorbs the water originally desorbed from the primary bed. The main advantage of the regeneration technique is that the partial pressure of water can be reduced to the 10.sup.-9 atm. range. This is significant in certain CTR applications where tritiated water (T.sub.2 O, HTO) must be collected and kept at very low partial pressure.
NASA Technical Reports Server (NTRS)
Nelson, D. P.; Morris, P. M.
1980-01-01
Aerodynamic performance and jet noise characteristics of a one sixth scale model of the variable cycle engine testbed exhaust system were obtained in a series of static tests over a range of simulated engine operating conditions. Model acoustic data were acquired. Data were compared to predictions of coannular model nozzle performance. The model, tested with an without a hardwall ejector, had a total flow area equivalent to a 0.127 meter (5 inch) diameter conical nozzle with a 0.65 fan to primary nozzle area ratio and a 0.82 fan nozzle radius ratio. Fan stream temperatures and velocities were varied from 422 K to 1089 K (760 R to 1960 R) and 434 to 755 meters per second (1423 to 2477 feet per second). Primary stream properties were varied from 589 to 1089 K (1060 R to 1960 R) and 353 to 600 meters per second (1158 to 1968 feet per second). Exhaust plume velocity surveys were conducted at one operating condition with and without the ejector installed. Thirty aerodynamic performance data points were obtained with an unheated air supply. Fan nozzle pressure ratio was varied from 1.8 to 3.2 at a constant primary pressure ratio of 1.6; primary pressure ratio was varied from 1.4 to 2.4 while holding fan pressure ratio constant at 2.4. Operation with the ejector increased nozzle thrust coefficient 0.2 to 0.4 percent.
Modeling and Analysis of Alternative Concept of ITER Vacuum Vessel Primary Heat Transfer System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carbajo, Juan J; Yoder Jr, Graydon L; Dell'Orco, Giovanni
2010-01-01
A RELAP5-3D model of the ITER (Latin for the way ) vacuum vessel (VV) primary heat transfer system has been developed to evaluate a proposed design change that relocates the heat exchangers (HXs) from the exterior of the tokamak building to the interior. This alternative design protects the HXs from external hazards such as wind, tornado, and aircraft crash. The proposed design integrates the VV HXs into a VV pressure suppression system (VVPSS) tank that contains water to condense vapour in case of a leak into the plasma chamber. The proposal is to also use this water as the ultimatemore » sink when removing decay heat from the VV system. The RELAP5-3D model has been run under normal operating and abnormal (decay heat) conditions. Results indicate that this alternative design is feasible, with no effects on the VVPSS tank under normal operation and with tank temperature and pressure increasing under decay heat conditions resulting in a requirement to remove steam generated if the VVPSS tank low pressure must be maintained.« less
Pressurizer with a mechanically attached surge nozzle thermal sleeve
Wepfer, Robert M
2014-03-25
A thermal sleeve is mechanically attached to the bore of a surge nozzle of a pressurizer for the primary circuit of a pressurized water reactor steam generating system. The thermal sleeve is attached with a series of keys and slots which maintain the thermal sleeve centered in the nozzle while permitting thermal growth and restricting flow between the sleeve and the interior wall of the nozzle.
Plasma parameters in a multidipole plasma system
NASA Astrophysics Data System (ADS)
Ruscanu, D.; Anita, V.; Popa, G.
Plasma potential and electron number densities and electron temperatures under bi-Maxwellian approximation for electron distribution function of the multidipole argon plasma source system were measured for a gas pressure ranging between 10-4 and 10-3 mbar and an anode-cathode voltage ranging between 40 and 120 V but a constant discharge current intensity. The first group, as ultimate or cold electrons and main electron plasma population, results by trapping of the slow electrons produced by ionisation process due to primary-neutral collisions. The trapping process is produced by potential well due to positive plasma potential with respect to the anode so that electron temperature of the ultimate electrons does not depend on both the gas pressure and discharge voltage. The second group, as secondary or hot electrons, results as degrading process of the primaries and their number density increases while their temperature decreases with the increase of both the gas pressure and discharge voltage.
NASA Technical Reports Server (NTRS)
Sherif, S.A.; Hunt, P. L.; Holladay, J. B.; Lear, W. E.; Steadham, J. M.
1998-01-01
Jet pumps are devices capable of pumping fluids to a higher pressure by inducing the motion of a secondary fluid employing a high speed primary fluid. The main components of a jet pump are a primary nozzle, secondary fluid injectors, a mixing chamber, a throat, and a diffuser. The work described in this paper models the flow of a two-phase primary fluid inducing a secondary liquid (saturated or subcooled) injected into the jet pump mixing chamber. The model is capable of accounting for phase transformations due to compression, expansion, and mixing. The model is also capable of incorporating the effects of the temperature and pressure dependency in the analysis. The approach adopted utilizes an isentropic constant pressure mixing in the mixing chamber and at times employs iterative techniques to determine the flow conditions in the different parts of the jet pump.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riess, R.
Chosen for this description of the selected Kraftwerk Union (KWU) pressurized water reactor units were Obrigheim (KWO, 345 MW(e)), Stade (KKS, 662 (MW(e)), Borselle (KCB, 477 MW(e)), and Biblis (KWB-A, 1204 MW(e)). The experience at these plants shows that with a special startup procedure and a proper chemical control of the primary heat transport system that influences general corrosion, selective types of corrosion, corrosion product activity transport and resulting contamination, and radiation-induced decomposition, KWU units have no basic problems.
A model for the space shuttle main engine high pressure oxidizer turbopump shaft seal system
NASA Technical Reports Server (NTRS)
Paxson, Daniel E.
1990-01-01
A simple static model is presented which solves for the flow properties of pressure, temperature, and mass flow in the Space Shuttle Main Engine pressure Oxidizer Turbopump Shaft Seal Systems. This system includes the primary and secondary turbine seals, the primary and secondary turbine drains, the helium purge seals and feed line, the primary oxygen drain, and the slinger/labyrinth oxygen seal pair. The model predicts the changes in flow variables that occur during and after failures of the various seals. Such information would be particularly useful in a post flight situation where processing of sensor information using this model could identify a particular seal that had experienced excessive wear. Most of the seals in the system are modeled using simple one dimensional equations which can be applied to almost any seal provided that the fluid is gaseous. A failure is modeled as an increase in the clearance between the shaft and the seal. Thus, the model does not attempt to predict how the failure process actually occurs (e.g., wear, seal crack initiation). The results presented were obtained using a FORTRAN implementation of the model running on a VAX computer. Solution for the seal system properties is obtained iteratively; however, a further simplified implementation (which does not include the slinger/labyrinth combination) was also developed which provides fast and reasonable results for most engine operating conditions. Results from the model compare favorably with the limited redline data available.
A computational analysis of the long-term regulation of arterial pressure
Beard, Daniel A.
2013-01-01
The asserted dominant role of the kidneys in the chronic regulation of blood pressure and in the etiology of hypertension has been debated since the 1970s. At the center of the theory is the observation that the acute relationships between arterial pressure and urine production—the acute pressure-diuresis and pressure-natriuresis curves—physiologically adapt to perturbations in pressure and/or changes in the rate of salt and volume intake. These adaptations, modulated by various interacting neurohumoral mechanisms, result in chronic relationships between water and salt excretion and pressure that are much steeper than the acute relationships. While the view that renal function is the dominant controller of arterial pressure has been supported by computer models of the cardiovascular system known as the “Guyton-Coleman model”, no unambiguous description of a computer model capturing chronic adaptation of acute renal function in blood pressure control has been presented. Here, such a model is developed with the goals of: 1. representing the relevant mechanisms in an identifiable mathematical model; 2. identifying model parameters using appropriate data; 3. validating model predictions in comparison to data; and 4. probing hypotheses regarding the long-term control of arterial pressure and the etiology of primary hypertension. The developed model reveals: long-term control of arterial blood pressure is primarily through the baroreflex arc and the renin-angiotensin system; and arterial stiffening provides a sufficient explanation for the etiology of primary hypertension associated with ageing. Furthermore, the model provides the first consistent explanation of the physiological response to chronic stimulation of the baroreflex. PMID:24555102
A computational analysis of the long-term regulation of arterial pressure.
Beard, Daniel A; Pettersen, Klas H; Carlson, Brian E; Omholt, Stig W; Bugenhagen, Scott M
2013-01-01
The asserted dominant role of the kidneys in the chronic regulation of blood pressure and in the etiology of hypertension has been debated since the 1970s. At the center of the theory is the observation that the acute relationships between arterial pressure and urine production-the acute pressure-diuresis and pressure-natriuresis curves-physiologically adapt to perturbations in pressure and/or changes in the rate of salt and volume intake. These adaptations, modulated by various interacting neurohumoral mechanisms, result in chronic relationships between water and salt excretion and pressure that are much steeper than the acute relationships. While the view that renal function is the dominant controller of arterial pressure has been supported by computer models of the cardiovascular system known as the "Guyton-Coleman model", no unambiguous description of a computer model capturing chronic adaptation of acute renal function in blood pressure control has been presented. Here, such a model is developed with the goals of: 1. representing the relevant mechanisms in an identifiable mathematical model; 2. identifying model parameters using appropriate data; 3. validating model predictions in comparison to data; and 4. probing hypotheses regarding the long-term control of arterial pressure and the etiology of primary hypertension. The developed model reveals: long-term control of arterial blood pressure is primarily through the baroreflex arc and the renin-angiotensin system; and arterial stiffening provides a sufficient explanation for the etiology of primary hypertension associated with ageing. Furthermore, the model provides the first consistent explanation of the physiological response to chronic stimulation of the baroreflex.
40 CFR 141.63 - Maximum contaminant levels (MCLs) for microbiological contaminants.
Code of Federal Regulations, 2012 CFR
2012-07-01
... water pressure in all parts of the distribution system; (4) Filtration and/or disinfection of surface water, as described in subpart H, or disinfection of ground water using strong oxidants such as chlorine... (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS National Primary Drinking...
Boiler and Pressure Balls Monopropellant Thermal Rocket Engine
NASA Technical Reports Server (NTRS)
Greene, William D. (Inventor)
2009-01-01
The proposed technology is a rocket engine cycle utilizing as the propulsive fluid a low molecular weight, cryogenic fluid, typically liquid hydrogen, pressure driven, heated, and expelled through a nozzle to generate high velocity and high specific impulse discharge gas. The proposed technology feeds the propellant through the engine cycle without the use of a separate pressurization fluid and without the use of turbomachinery. Advantages of the proposed technology are found in those elements of state-of-the-art systems that it avoids. It does not require a separate pressurization fluid or a thick-walled primary propellant tank as is typically required for a classical pressure-fed system. Further, it does not require the acceptance of intrinsic reliability risks associated with the use of turbomachinery
49 CFR 173.318 - Cryogenic liquids in cargo tanks.
Code of Federal Regulations, 2014 CFR
2014-10-01
... than two times the tank's design pressure. (6) Maximum filling rate. (i) For a tank used in oxygen and... the design service temperature of the packaging. (2) A cargo tank may not be loaded with any material... two independent pressure relief systems which are not connected in series, namely: (A) A primary...
49 CFR 173.318 - Cryogenic liquids in cargo tanks.
Code of Federal Regulations, 2013 CFR
2013-10-01
... than two times the tank's design pressure. (6) Maximum filling rate. (i) For a tank used in oxygen and... the design service temperature of the packaging. (2) A cargo tank may not be loaded with any material... two independent pressure relief systems which are not connected in series, namely: (A) A primary...
49 CFR 173.318 - Cryogenic liquids in cargo tanks.
Code of Federal Regulations, 2011 CFR
2011-10-01
... than two times the tank's design pressure. (6) Maximum filling rate. (i) For a tank used in oxygen and... the design service temperature of the packaging. (2) A cargo tank may not be loaded with any material... two independent pressure relief systems which are not connected in series, namely: (A) A primary...
49 CFR 173.318 - Cryogenic liquids in cargo tanks.
Code of Federal Regulations, 2010 CFR
2010-10-01
... than two times the tank's design pressure. (6) Maximum filling rate. (i) For a tank used in oxygen and... the design service temperature of the packaging. (2) A cargo tank may not be loaded with any material... two independent pressure relief systems which are not connected in series, namely: (A) A primary...
Exploring Sources of Variation in Romanian Science Achievement
ERIC Educational Resources Information Center
Istrate, Olimpius; Noveanu, Gabriela; Smith, Thomas M.
2006-01-01
The shift from a centrally-controlled to a market-oriented economy in the early 1990s put pressure on the Romanian education system to reform both the curriculum and methods of instruction employed in primary and secondary education. At least part of the pressure to implement educational reforms came from the relatively poor performance of…
Digibaro pressure instrument onboard the Phoenix Lander
NASA Astrophysics Data System (ADS)
Harri, A.-M.; Polkko, J.; Kahanpää, H. H.; Schmidt, W.; Genzer, M. M.; Haukka, H.; Savijarv1, H.; Kauhanen, J.
2009-04-01
The Phoenix Lander landed successfully on the Martian northern polar region. The mission is part of the National Aeronautics and Space Administration's (NASA's) Scout program. Pressure observations onboard the Phoenix lander were performed by an FMI (Finnish Meteorological Institute) instrument, based on a silicon diaphragm sensor head manufactured by Vaisala Inc., combined with MDA data processing electronics. The pressure instrument performed successfully throughout the Phoenix mission. The pressure instrument had 3 pressure sensor heads. One of these was the primary sensor head and the other two were used for monitoring the condition of the primary sensor head during the mission. During the mission the primary sensor was read with a sampling interval of 2 s and the other two were read less frequently as a check of instrument health. The pressure sensor system had a real-time data-processing and calibration algorithm that allowed the removal of temperature dependent calibration effects. In the same manner as the temperature sensor, a total of 256 data records (8.53 min) were buffered and they could either be stored at full resolution, or processed to provide mean, standard deviation, maximum and minimum values for storage on the Phoenix Lander's Meteorological (MET) unit.The time constant was approximately 3s due to locational constraints and dust filtering requirements. Using algorithms compensating for the time constant effect the temporal resolution was good enough to detect pressure drops associated with the passage of nearby dust devils.
Mills, Katherine T.; Rubinstein, Adolfo; Irazola, Vilma; Chen, Jing; Beratarrechea, Andrea; Poggio, Rosana; Dolan, Jacquelyn; Augustovski, Federico; Shi, Lizheng; Krousel-Wood, Marie; Bazzano, Lydia A.; He, Jiang
2014-01-01
Although the efficacy and effectiveness of lifestyle modifications and antihypertensive pharmaceutical treatment for the prevention and control of hypertension and concomitant cardiovascular disease have been demonstrated in randomized controlled trials, this scientific knowledge has not been fully applied in the general population, especially in low-income communities. This paper summarizes interventions to improve hypertension management and describes the rationale and study design for a cluster randomized trial testing whether a comprehensive intervention program within a national public primary care system will improve hypertension control among uninsured hypertensive men and women and their families. We will recruit 1,890 adults from 18 clinics within a public primary care network in Argentina. Clinic patients with uncontrolled hypertension, their spouses and hypertensive family members will be enrolled. The comprehensive intervention program targets the primary care system through health care provider education, a home-based intervention among patients and their families (home delivery of antihypertensive medication, self-monitoring of blood pressure, health education for medication adherence and lifestyle modification) conducted by community health workers, and a mobile health intervention. The primary outcome is net change in systolic blood pressure from baseline to month 18 between intervention and control groups among hypertensive study participants. The secondary outcomes are net change in diastolic blood pressure, blood pressure control, and cost-effectiveness of the intervention. This study will generate urgently needed data on effective, practical, and sustainable intervention programs aimed at controlling hypertension and concomitant cardiovascular disease in underserved populations in low- and middle-income countries. PMID:24978148
Analytical and computational studies on the vacuum performance of a chevron ejector
NASA Astrophysics Data System (ADS)
Kong, F. S.; Jin, Y. Z.; Kim, H. D.
2016-11-01
The effects of chevrons on the performance of a supersonic vacuum ejector-diffuser system are investigated numerically and evaluated theoretically in this work. A three-dimensional geometrical domain is numerically solved using a fully implicit finite volume scheme based on the unsteady Reynolds stress model. A one-dimensional mathematical model provides a useful tool to reveal the steady flow physics inside the vacuum ejector-diffuser system. The effects of the chevron nozzle on the generation of recirculation regions and Reynolds stress behaviors are studied and compared with those of a conventional convergent nozzle. The present performance parameters obtained from the simulated results and the mathematical results are validated with existing experimental data and show good agreement. Primary results show that the duration of the transient period and the secondary chamber pressure at a dynamic equilibrium state depend strongly on the primary jet conditions, such as inlet pressure and primary nozzle shape. Complicated oscillatory flow, generated by the unsteady movement of recirculation, finally settles into a dynamic equilibrium state. As a vortex generator, the chevron demonstrated its strong entrainment capacity to accelerate the starting transient flows to a certain extent and reduce the dynamic equilibrium pressure of the secondary chamber significantly.
NASA Astrophysics Data System (ADS)
Lee, Jung-Moo; Kang, Suk-Bong; Yoon, Sang-Chul
1999-07-01
The wear behavior of hypereutectic aluminium-silicon alloy A390 was investigated using a pin-on-disc wear machine under dry sliding conditions. The wear tests were performed within a load range of 10 to 300N at a constant sliding velocity of 0.5 m/sec. The microstructural and compositional changes that took place during wear were characterized by scanning electron microscopy (SEM) equipped with an energy dispersive X-ray analysis (EDXA) system. Based on the metallographic observations the role of the primary silicon particles was suggested. In a low pressure region, primary silicon particles supported the applied load and wear occurred mainly in the matrix. Thus the wear loss did not show much variation with the applied load. In the mid-load range, primary silicon particles did not yet fracture and thus supported the applied load in part. Transition from oxidative to metallic wear occurs mainly in the matrix and the increase of wear loss becomes sharper than that in a low pressure region. In the high pressure region, the fractures of primary silicon Particles occurred and wear loss increased sharply.
Structural Concepts and Materials for Lunar Exploration Habitats
NASA Technical Reports Server (NTRS)
Belvin, W. Keith; Watson, Judith J.; Singhal, Surendra N.
2006-01-01
A new project within the Exploration Systems Mission Directorate s Technology Development Program at NASA involves development of lightweight structures and low temperature mechanisms for Lunar and Mars missions. The Structures and Mechanisms project is to develop advanced structure technology for the primary structure of various pressurized elements needed to implement the Vision for Space Exploration. The goals are to significantly enhance structural systems for man-rated pressurized structures by 1) lowering mass and/or improving efficient volume for reduced launch costs, 2) improving performance to reduce risk and extend life, and 3) improving manufacturing and processing to reduce costs. The targeted application of the technology is to provide for the primary structure of the pressurized elements of the lunar lander for both sortie and outpost missions, and surface habitats for the outpost missions. The paper presents concepts for habitats that support six month (and longer) lunar outpost missions. Both rigid and flexible habitat wall systems are discussed. The challenges of achieving a multi-functional habitat that provides micro-meteoroid, radiation, and thermal protection for explorers are identified.
Providing Oxygen for the Crew of a Lunar Outpost
NASA Technical Reports Server (NTRS)
Ewert, Michael K.; Jeng, Frank; Conger, Bruce; Anderson, Molly S.
2009-01-01
Oxygen (O2) is obviously essential for human space missions, but it is important to examine all the different ways it will be used and the potential sources that it may come from. This effort will lead to storage and delivery requirements and help to determine the optimum architecture from an overall systems engineering point of view. Accounting for all the oxygen in a Lunar Outpost mission includes meeting the metabolic needs of the crew while in the surface Habitat, leakage through the Habitat or Pressurized Rover walls, recharge of the space suit backpack and emergency situations. Current plans indicate that both primary and secondary O2 bottles for the space suit will be filled to a pressure of 20.7 MPa (3000 psia). Other uses of O2 require much lower pressure. Sources of O2 at a Lunar Outpost include compressed or liquefied O2 brought along specifically for life support, scavenged O2 from the Lander propulsion system, recovered O2 from waste water or exhaled carbon dioxide and O2 mined from the moon itself. Previously, eight technology options were investigated to provide the high pressure space suit O2. High pressure O2 storage was treated as the baseline technology and compared to the other seven. The other seven were cryogenic storage followed by high pressure vaporization, scavenging liquid oxygen (LOX) from Lander followed by vaporization, LOX delivery followed by sorption compression, low pressure water electrolysis followed by mechanical compression, high pressure water electrolysis, sharing a high pressure electrolyzer with a regenerative fuel cell power system, and making use of In- Situ Resource Utilization (ISRU). This system-level analysis was conducted by comparing equivalent system mass of the eight technologies in open and closed loop life support architectures. The most promising high pressure O2 generation technologies were recommended for development. Updates and an expansion of the earlier study have been made and the results are reported in this paper. Examples of recent analyses include feasibility of recovering space suit purge O2 in a Pressurized Rover and using sub-critical LOX for primary supply while using high-pressure gaseous O2 as the secondary supply for the space-suit. Preliminary analysis on scavenging LOX from the Lander and delivering it to the Habitat has also been incorporated into this integrated lunar fluids analysis
Patient-centered primary health care: synergy potential for health systems strengthening.
Stender, S C; Christensen, A
2013-10-01
The ultimate goal of government health systems is to provide highly effective equitable services that save lives and reduce morbidity and mortality. The pressure to conform to duplicative global and donor initiatives compounds existing challenges to health systems strengthening such as shortages of human resources for health, weak supply chains, inadequate laboratory services and parallel data management systems. This article illustrates how primary health care, as the point of entry into the health care system for the majority of individuals in sub-Saharan Africa, should be strengthened to ensure that individuals and their communities receive essential, holistic care.
E-health blood pressure control program.
Ahern, David K; Stinson, Lynda J; Uebelacker, Lisa A; Wroblewski, Joseph P; McMurray, Jerome H; Eaton, Charles B
2012-01-01
Both technological and human factors design requirements for integration of home blood pressure monitoring (HBPM) into a patient centered medical home (PCMH) model primary care practice are described. Patients with uncontrolled hypertension were given home blood pressure (BP) monitors, and after a three-month run-in period introduced to either a high-tech only (HBPM connectivity to personal health record and tailored Web portal access) or a high-tech/"high-touch" (high-tech solution plus patient navigator [PN]) solution. Features of the Web portal included: BP graphing function, traffic-light feedback system of BP goal attainment, economic incentives for self-monitoring, and dual patient-facing and care-team-facing dashboard functions. The e-health BP control system with PN support was well received by patients, providers, and the healthcare team. Current e-health technology and limited technological literacy of many patients suggest that a PN or some other personnel resource may be required for the adoption of patient-facing technology in primary care.
Analytical Assessment of the Reciprocating Feed System
NASA Technical Reports Server (NTRS)
Eddleman, David E.; Blackmon, James B.; Morton, Christopher D.
2006-01-01
A preliminary analysis tool has been created in Microsoft Excel to determine deliverable payload mass, total system mass, and performance of spacecraft systems using various types of propellant feed systems. These mass estimates are conducted by inserting into the user interface the basic mission parameters (e.g., thrust, burn time, specific impulse, mixture ratio, etc.), system architecture (e.g., propulsion system type and characteristics, propellants, pressurization system type, etc.), and design properties (e.g., material properties, safety factors, etc.). Different propellant feed and pressurization systems are available for comparison in the program. This gives the user the ability to compare conventional pressure fed, reciprocating feed system (RFS), autogenous pressurization thrust augmentation (APTA RFS), and turbopump systems with the deliverable payload, inert mass, and total system mass being the primary comparison metrics. Analyses of several types of missions and spacecraft were conducted and it was found that the RFS offers a performance improvement, especially in terms of delivered payload, over conventional pressure fed systems. Furthermore, it is competitive with a turbopump system at low to moderate chamber pressures, up to approximately 1,500 psi. Various example cases estimating the system mass and deliverable payload of several types of spacecraft are presented that illustrate the potential system performance advantages of the RFS. In addition, a reliability assessment of the RFS was conducted, comparing it to simplified conventional pressure fed and turbopump systems, based on MIL-STD 756B; these results showed that the RFS offers higher reliability, and thus substantially longer periods between system refurbishment, than turbopump systems, and is competitive with conventional pressure fed systems. This is primarily the result of the intrinsic RFS fail-operational capability with three run tanks, since the system can operate with just two run tanks.
Development of Trace Contaminant Control Prototypes for the Primary Life Support System (PLSS)
NASA Technical Reports Server (NTRS)
Wojtowicz, Marek; Cosgrove, Joseph E.; Serio, Michael E.; Nalette, Tim; Guerrero, Sandra V.; Papale, William; Wilburn, Monique S.
2017-01-01
Results are presented on the development of Trace Contaminant Control (TCC) Prototypes for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). The current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is non-regenerable, and the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. Data on sorption and desorption of ammonia and formaldehyde, which are major TCs of concern, as well as pressure-drop calculations were used to design and test 1/6-scale and full-scale trace contaminant control system (TCCS) prototypes. Carbon sorbents were fabricated in both the granular and foam-supported forms. Sorbent performance was tested for ammonia sorption and vacuum regeneration in 1/6-scale, and pressure-drop characteristics were measured at flow rates relevant to the PLSS application.
A company-instituted program to improve blood pressure control in primary care.
Alderman, M H; Melcher, L A
1981-01-01
An occupation-based effort to improve the outcome of antihypertensive therapy provided in the community was instituted by the Massachusetts Mutual Life Insurance Company in 1977. The goal of the program was to utilize the administrative and organizational resources of the company to enhance employee/patient adherence to treatment provided in conventional primary care settings. Key elements of the program were: companywide education and on-site screening, referral to community physicians and company assumption of all patient costs, linked to a monitoring system to permit oversight of care. Initially, 98% of employees were screened, 70% accepted referral for care and 59% fully adhered to program performance criteria. Blood pressure control has risen from 36% at the beginning to 69% at the end of the second year. Fully compliant patients have achieved the greatest lowering of blood pressure and compiled the best work attendance record. Program costs are modest and acceptance by employees and physicians supports the concept that occupation-based, systematic efforts can enhance the impact of primary care.
NASA Technical Reports Server (NTRS)
1973-01-01
A computer program for space shuttle orbit injection propulsion system analysis (SOPSA) is described to show the operational characteristics and the computer system requirements. The program was developed as an analytical tool to aid in the preliminary design of propellant feed systems for the space shuttle orbiter main engines. The primary purpose of the program is to evaluate the propellant tank ullage pressure requirements imposed by the need to accelerate propellants rapidly during the engine start sequence. The SOPSA program will generate parametric feed system pressure histories and weight data for a range of nominal feedline sizes.
Low Pressure Greenhouse Concepts for Mars
NASA Technical Reports Server (NTRS)
Fowler, Philip A.; Wheeler, Raymond M.; Bucklin, Ray A.; Corey, Kenneth A.
2000-01-01
A project was initiated to begin testing some environmental limits for managing plant growth systems. These limits will help determine some of the concepts for building plant enclosures for use on Mars. In particular, this study focuses on the effects of reduced atmospheric pressures. Structural design is considered as it relates to the biological processes that would occur within that structure. The design must be closely tied to the functionality of the biological system and has a few primary concerns that need to be tested to resolve the question as to the path of the design. Early tests indicate that plants can survive and grow at low (greater than 76 mb) pressure.
Praveen, Devarsetty; Patel, Anushka; McMahon, Stephen; Prabhakaran, Dorairaj; Clifford, Gari D; Maulik, Pallab K; Joshi, Rohina; Jan, Stephen; Heritier, Stephane; Peiris, David
2013-11-25
Blood Pressure related disease affected 118 million people in India in the year 2000; this figure will double by 2025. Around one in four adults in rural India have hypertension, and of those, only a minority are accessing appropriate care. Health systems in India face substantial challenges to meet these gaps in care, and innovative solutions are needed. We hypothesise that a multifaceted intervention involving capacity strengthening of primary healthcare doctors and non-physician healthcare workers through use of a mobile device-based clinical decision support system will result in improved blood pressure control for individuals at high risk of a cardiovascular disease event when compared with usual healthcare. This intervention will be implemented as a stepped wedge, cluster randomised controlled trial in 18 primary health centres and 54 villages in rural Andhra Pradesh involving adults aged ≥40 years at high cardiovascular disease event risk (approximately 15,000 people). Cardiovascular disease event risk will be calculated based on World Health Organisation/International Society of Hypertension's region-specific risk charts. Cluster randomisation will occur at the level of the primary health centres. Outcome analyses will be conducted blinded to intervention allocation. The primary study outcome is the difference in the proportion of people meeting guideline-recommended blood pressure targets in the intervention period vs. the control period. Secondary outcomes include mean reduction in blood pressure levels; change in other cardiovascular disease risk factors, including body mass index, current smoking, reported healthy eating habits, and reported physical activity levels; self-reported use of blood pressure and other cardiovascular medicines; quality of life (using the EQ-5D); and cardiovascular disease events (using hospitalisation data). Trial outcomes will be accompanied by detailed process and economic evaluations. The findings are likely to inform policy on a scalable strategy to overcome entrenched inequities in access to effective healthcare for under-served populations in low and middle income country settings. Clinical Trial Registry India CTRI/2013/06/003753.
NASA Technical Reports Server (NTRS)
Butt, Adam; Popp, Christopher G.; Holt, Kimberly A.; Pitts, Hank M.
2010-01-01
The Ares I launch vehicle is the selected design, chosen to return humans to the moon, Mars, and beyond. It is configured in two inline stages: the First Stage is a Space Shuttle derived five-segment Solid Rocket Booster and the Upper Stage is powered by a Saturn V derived J-2X engine. During launch, roll control for the First Stage (FS) is handled by a dedicated Roll Control System (RoCS) located on the connecting Interstage. That system will provide the Ares I with the ability to counteract induced roll torque while any induced yaw or pitch moments are handled by vectoring of the booster nozzle. This paper provides an overview of NASA s Ares I FS RoCS cold flow development test program including detailed test objectives, types of tests run to meet those objectives, an overview of the results, and applicable lessons learned. The test article was built and tested at the NASA Marshall Space Flight Center in Huntsville, AL. The FS RoCS System Development Test Article (SDTA) is a full scale, flight representative water flow test article whose primary objective was to obtain fluid system performance data to evaluate integrated system level performance characteristics and verify analytical models. Development testing and model correlation was deemed necessary as there is little historical precedent for similar large flow, pulsing systems such as the FS RoCS. The cold flow development test program consisted of flight-similar tanks, pressure regulators, and thruster valves, as well as plumbing simulating flight geometries, combined with other facility grade components and structure. Orifices downstream of the thruster valves were used to simulate the pressure drop through the thrusters. Additional primary objectives of this test program were to: evaluate system surge pressure (waterhammer) characteristics due to thruster valve operation over a range of mission duty cycles at various feed system pressures, evaluate temperature transients and heat transfer in the pressurization system, including regulator blowdown and propellant ullage performance, measure system pressure drops for comparison to analysis of tubing and components, and validate system activation and re-activation procedures for the helium pressurant system. Secondary objectives included: validating system processes for loading, unloading, and purging, validating procedures and system response for multiple failure scenarios, including relief valve operation, and evaluating system performance for contingency scenarios. The test results of the cold flow development test program are essential in validating the performance and interaction of the Roll Control System and anchoring analysis tools and results to a Critical Design Review level of fidelity.
Photochemically Etched Construction Technology Developed for Digital Xenon Feed Systems
NASA Technical Reports Server (NTRS)
Otsap, Ben; Cardin, Joseph; Verhey, Timothy R.; Rawlin, Vincent K.; Mueller, Juergen; Aadlund, Randall; Kay, Robert; Andrews, Michael
2005-01-01
Electric propulsion systems are quickly emerging as attractive options for primary propulsion in low Earth orbit, in geosynchronous orbit, and on interplanetary spacecraft. The driving force behind the acceptance of these systems is the substantial reduction in the propellant mass that can be realized. Unfortunately, system designers are often forced to utilize components designed for chemical propellants in their electric systems. Although functionally acceptable, these relatively large, heavy components are designed for the higher pressures and mass flow rates required by chemical systems. To fully realize the benefits of electric propulsion, researchers must develop components that are optimized for the low flow rates, critical leakage needs, low pressures, and limited budgets of these emerging systems.
NASA Technical Reports Server (NTRS)
Parker, C. D.
1975-01-01
The Pioneer 10/11 meteoroid detection equipment (MDE) pressure cells were tested at liquid nitrogen (LN2) and liquid helium (LHe) temperatures with the excitation voltage controlled as a parameter. The cells failed by firing because of pressurizing gas condensation as the temperature was lowered from LN2 to LHe temperature and when raised from LHe temperature. A study was conducted to determine cell pressure as a function of temperature, and cell failure was estimated as a function of temperature and excitation voltage. The electronic system was also studied, and a profile of primary spacecraft voltage (nominally 28 Vdc) and temperature corresponding to electronic system failure was determined experimentally.
Code of Federal Regulations, 2012 CFR
2012-04-01
... increasing pressure to balance their budgets and, at the same time, respond to public demands for quality... life-cycle cost. The primary outcome of transportation management systems is improved system...)(1) and 23 U.S.C. 134(a)); congestion mitigation and air quality improvement program funds for those...
Code of Federal Regulations, 2011 CFR
2011-04-01
... increasing pressure to balance their budgets and, at the same time, respond to public demands for quality... life-cycle cost. The primary outcome of transportation management systems is improved system...)(1) and 23 U.S.C. 134(a)); congestion mitigation and air quality improvement program funds for those...
Code of Federal Regulations, 2010 CFR
2010-04-01
... increasing pressure to balance their budgets and, at the same time, respond to public demands for quality... life-cycle cost. The primary outcome of transportation management systems is improved system...)(1) and 23 U.S.C. 134(a)); congestion mitigation and air quality improvement program funds for those...
2015-03-01
statistically significant increase in systemic vascular resistance compared to control, but not whole blood, with a concomitant decrease in cardiac...increasing blood pressure as well as sys- temic vascular resistance in a hypovolemic hemorrhagic swine model.18 The primary hypothesis of this study is...output, sys- temic vascular resistance , mixed venous oxygen satura- tion, central venous pressure, pulmonary artery pressure, and core temperature. The
Bengtsson, Ulrika; Kjellgren, Karin; Hallberg, Inger; Lundin, Mona; Mäkitalo, Åsa
2018-03-01
This paper reports on how the clinical consultation in primary care is performed under the new premises of patients' daily self-reporting and self-generation of data. The aim was to explore and describe the structure, topic initiation and patients' contributions in follow-up consultations after eight weeks of self-reporting through a mobile phone-based hypertension self-management support system. A qualitative, explorative study design was used, examining 20 audio- (n = 10) and video-recorded (n = 10) follow-up consultations in primary care hypertension management, through interaction analysis. Clinical trials registry: ClinicalTrials.gov NCT01510301. Four primary health care centers in Sweden. Patients with hypertension (n = 20) and their health care professional (n = 7). The consultations comprised three phases: opening, examination and closing. The most common topic was blood pressure (BP) put in relation to self-reported variables, for example, physical activity and stress. Topic initiation was distributed symmetrically between parties and BP talk was lifestyle-centered. The patients' contributed to the interpretation of BP values by connecting them to specific occasions, providing insights to the link between BP measurements and everyday life activities. Patients' contribution through interpretations of BP values to specific situations in their own lives brought on consultations where the patient as a person in context became salient. Further, the patients' and health care professionals' equal contribution during the consultations showed actively involved patients. The mobile phone-based self-management support system can thus be used to support patient involvement in consultations with a person-centered approach in primary care hypertension management Key points The clinical consultation is important to provide opportunities for patients to gain understanding of factors affecting high blood pressure, and for health care professionals to motivate and promote changes in life-style. This study shows that self-reporting as base for follow-up consultations in primary care hypertension management can support patients and professionals to equal participation in clinical consultations. Self-reporting combined with increased patient-health care professional interaction during follow-up consultations can support patients in understanding the blood pressure value in relation to their daily life. These findings implicate that the interactive mobile phone self-management support system has potential to support current transformations of patients as recipients of primary care, to being actively involved in their own health.
ERIC Educational Resources Information Center
Irwin, Michael Ray
2018-01-01
This article reports on the understandings and practices of primary teachers in implementing the arts curriculum since the 2010 introduction of National Standards in Numeracy and Literacy within the New Zealand Education system. The ever-mounting pressure on schools to perform to these standards has resulted in a reduction of emphasis and time…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schnabel, Claus
Kick-off of the Bosch scope of work for the REGIS project started in October 2012. The primary work-packages included in the Bosch scope of work were the following: overall project management, development of the EGR sensor (design of sensor element, design of protection tube, and design of mounting orientation), development of EGR system control strategy, build-up of prototype sensors, evaluation of system performance with the new sensor and the new control strategy, long-term durability testing, and development of a 2nd generation sensor concept for continued technology development after the REGIS project. The University of Clemson was a partner with Boschmore » in the REGIS project. The Clemson scope of work for the REGIS project started in June 2013. The primary work-packages included in the Clemson scope of work were the following: development of EGR system control strategy, and evaluation of system performance with the new sensor and new control strategy. This project was split into phase I, phase II and phase III. Phase I work was completed by the end of June 2014 and included the following primary work packages: development of sensor technical requirements, assembly of engine testbench at Clemson, design concept for sensor housing, connector, and mounting orientation, build-up of EGR flow test benches at Bosch, and build-up of first sensor prototypes. Phase II work was completed by the end of June 2015 and included the following primary work pack ages: development of an optimizing function and demonstration of robustness of sensor, system control strategy implementation and initial validation, completion of engine in the loop testing of developed control algorithm, completion of sensor testing including characteristic line, synthetic gas test stand, and pressure dependency characterization, demonstration of benefits of control w/o sensing via simulation, development of 2nd generation sensor concept. Notable technical achievements from phase II were the following: publication of two new technical papers by Clemson detailing the control strategies used for the EGR system control. The two papers was published in the 2016 SAE World Congress in April 2016. The titles of each paper are, “Physics-Based Exhaust Pressure and Temperature Estimation for Low Pressure EGR Control in Turbocharged Gasoline Engines,” by K. Siokos, and “A Control Algorithm for Low Pressure – EGR Systems using a Smith Predictor with Intake Oxygen Sensor Feedback”, by R. Koli. All phase III work packages have been completed. The primary work packages in phase III were the following: completion of long-term sensor durability testing, final demonstration of benefits of EGR control w/o sensing, final decision of the second generation sensor development path.« less
Blood Pressure Measurement Guidelines for Physical Therapists
Fick, Ann; Sadowsky, H. Steven
2011-01-01
Vital sign measurement and assessment are important components of the review of systems in a physical therapy examination for individuals with and without documented cardiopulmonary disease. The measurement of blood pressure gives the therapist information regarding the patient's baseline cardiovascular status, response to exercise/activity, and guides exercise prescription. Accurate measurement of blood pressure is critical for making appropriate clinical decisions especially if physical therapists wish to play an important role as primary health care providers. The purpose of this paper is to present recommended guidelines for blood pressure measurement by physical therapists and physical therapist assistants. PMID:21637392
Blood pressure measurement guidelines for physical therapists.
Frese, Ethel M; Fick, Ann; Sadowsky, H Steven
2011-06-01
Vital sign measurement and assessment are important components of the review of systems in a physical therapy examination for individuals with and without documented cardiopulmonary disease. The measurement of blood pressure gives the therapist information regarding the patient's baseline cardiovascular status, response to exercise/activity, and guides exercise prescription. Accurate measurement of blood pressure is critical for making appropriate clinical decisions especially if physical therapists wish to play an important role as primary health care providers. The purpose of this paper is to present recommended guidelines for blood pressure measurement by physical therapists and physical therapist assistants.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nestler, J.M.; Schilt, C.R.; Jones, D.P.
1998-09-01
This report presents results of studies to predict the mortality rate of juvenile blueback herring (Alosa aestivalis) and American shad (A. sapidissima) associated with reduced pressure as they pass downstream through a proposed siphon water lift system at St. Stephen Dam, South Carolina. The primary function of the siphon is to increase attracting flow to better guide upstream migrating adult herring of both species into the existing fish lift for upstream passage. The US Army Engineer District, Charleston, wishes to consider the siphon as an alternative bypass route through the dam for downstream migrating juvenile and adult herring. A pressure-reductionmore » testing system that emulates some of the pressure characteristics of the siphon was used to determine the approximate percentage of juvenile fishes that could be reasonably expected to be killed passing through the reduced pressures anticipated for the siphon water lift system. The testing system could duplicate the range of pressure change anticipated for the siphon lift system but could not obtain pressures lower than 4.1 psi, whereas pressures for some design alternatives may approach the theoretical minimum pressure of 0.0 psi. Study results indicate that the mortality rate is probably about 20 percent. Power analysis indicates that mortality rate above 30 percent is unlikely. Conducting additional mortality studies is recommended to refine predicted mortality rates. Measures should be taken to prevent juvenile fish from entering the siphon lift system if excessive mortality rates are observed.« less
Relationship between orientation to a blast and pressure wave propagation inside the rat brain.
Chavko, Mikulas; Watanabe, Tomas; Adeeb, Saleena; Lankasky, Jason; Ahlers, Stephen T; McCarron, Richard M
2011-01-30
Exposure to a blast wave generated during an explosion may result in brain damage and related neurological impairments. Several mechanisms by which the primary blast wave can damage the brain have been proposed, including: (1) a direct effect of the shock wave on the brain causing tissue damage by skull flexure and propagation of stress and shear forces; and (2) an indirect transfer of kinetic energy from the blast, through large blood vessels and cerebrospinal fluid (CSF), to the central nervous system. To address a basic question related to the mechanisms of blast brain injury, pressure was measured inside the brains of rats exposed to a low level of blast (~35kPa), while positioned in three different orientations with respect to the primary blast wave; head facing blast, right side exposed to blast and head facing away from blast. Data show different patterns and durations of the pressure traces inside the brain, depending on the rat orientation to blast. Frontal exposures (head facing blast) resulted in pressure traces of higher amplitude and longer duration, suggesting direct transmission and reflection of the pressure inside the brain (dynamic pressure transfer). The pattern of the pressure wave inside the brain in the head facing away from blast exposures assumes contribution of the static pressure, similar to hydrodynamic pressure to the pressure wave inside the brain. Published by Elsevier B.V.
An Autonomous, Low Cost Platform for Seafloor Geodetic Observations
NASA Astrophysics Data System (ADS)
Ericksen, T.; Foster, J. H.; Bingham, B. S.; Oshiro, J.
2015-12-01
The Pacific GPS Facility and the Field Robotics Laboratory at the University of Hawaii have developed an approach to significantly reduce the costs of accurately measuring short-term vertical motions of the seafloor and maintaining a continuous long-term record of seafloor pressure. Traditional ship-based methods of acquiring these measurements are often prohibitively expensive. Our goal has been to reduce the primary barrier preventing us from acquiring the observations we need to understand geodetic processes, and the hazards they present, at subduction zones, submarine volcanoes, and subsea landslides. To this end, we have designed a payload package for the University of Hawaii Wave Glider which incorporates an acoustic telemetry package, a dual frequency geodetic-grade Global Positioning System (GPS) receiver, meteorological sensors, processing computer, and cellular communications. The Wave Glider is able to interrogate high accuracy pressure sensors on the seafloor to maintain a near-continuous stream of ocean bottom pressure and temperature data. The Wave Glider also functions as an integral part of the seafloor geodetic observing system, recording accurate sea surface elevations and barometric pressure; direct measurements of two of the primary sources of seafloor pressure change. The seafloor geodetic monument seats a sensor capable of recording pressure, temperature, and sound velocity for a deployment duration of over 5 years with an acoustic modem for communications, and an integral acoustic release for recovery and replacement of batteries. The design of the geodetic monument allows for precise repositioning of the sensor to extend the pressure record beyond a single 5+ year deployment, and includes the capability to install a mobile pressure recorder for calibration of the linear drift of the continuous pressure sensor. We will present the results of our field tests and an assessment of our ability to determine cm-scale vertical seafloor motions by integrating our seafloor pressure measurements with the independent Wave Glider measurements of sea surface pressure and sea surface height. An overall summary of the performance and costs of making seafloor geodetic measurement with this system will be provided.
Cooling Performance Analysis of ThePrimary Cooling System ReactorTRIGA-2000Bandung
NASA Astrophysics Data System (ADS)
Irianto, I. D.; Dibyo, S.; Bakhri, S.; Sunaryo, G. R.
2018-02-01
The conversion of reactor fuel type will affect the heat transfer process resulting from the reactor core to the cooling system. This conversion resulted in changes to the cooling system performance and parameters of operation and design of key components of the reactor coolant system, especially the primary cooling system. The calculation of the operating parameters of the primary cooling system of the reactor TRIGA 2000 Bandung is done using ChemCad Package 6.1.4. The calculation of the operating parameters of the cooling system is based on mass and energy balance in each coolant flow path and unit components. Output calculation is the temperature, pressure and flow rate of the coolant used in the cooling process. The results of a simulation of the performance of the primary cooling system indicate that if the primary cooling system operates with a single pump or coolant mass flow rate of 60 kg/s, it will obtain the reactor inlet and outlet temperature respectively 32.2 °C and 40.2 °C. But if it operates with two pumps with a capacity of 75% or coolant mass flow rate of 90 kg/s, the obtained reactor inlet, and outlet temperature respectively 32.9 °C and 38.2 °C. Both models are qualified as a primary coolant for the primary coolant temperature is still below the permitted limit is 49.0 °C.
Subsystem Analysis/Optimization for the X-34 Main Propulsion System
NASA Technical Reports Server (NTRS)
McDonald, J. P.; Hedayat, A.; Brown, T. M.; Knight, K. C.; Champion, R. H., Jr.
1998-01-01
The Orbital Sciences Corporation X-34 vehicle demonstrates technologies and operations key to future reusable launch vehicles. The general flight performance goal of this unmanned rocket plane is Mach 8 flight at an altitude of 250,000 feet. The Main Propulsion System (MPS) supplies liquid propellants to the main engine, which provides the primary thrust for attaining mission goals. Major MPS design and operational goals are aircraft-like ground operations, quick turnaround between missions, and low initial/operational costs. Analyses related to optimal MPS subsystem design are reviewed in this paper. A pressurization system trade weighs maintenance/reliability concerns against those for safety in a comparison of designs using pressure regulators versus orifices to control pressurant flow. A propellant dump/feed system analysis weighs the issues of maximum allowable vehicle landing weight, trajectory, and MPS complexity to arrive at a final configuration for propellant dump/feed systems.
[Decubitus ulcer in the calcaneus region: rapid development, difficult recovery].
Fugazza, G; Bona, F
1996-03-01
Heel pressure sores frequently arise in patients kept in bed for a long time independently of their primary disease. In account of this event the authors completed a study concerning possible mutual relations between heel pressure sores and primary disease of the patients; to validate the pharmacological treatment in less severe sores and the surgical resolution in more serious cutaneous lesions. In the last 3 years (1992-1995) at the Rehabilitation Centre of Montescano the authors have treated 39 patients suffering from 63 different severe cutaneous lesions: from phlycten to deep necrosis. The therapeutic plane utilized pharmacological treatment for 1st, 2nd, 3rd degree pressure sores, and surgical treatment for 4th degree. Pharmacological treatment included: enzymatic drugs, bactericidal and bacteriostatic medicines and cicatrizing substances. Different healing times were related to different pressure sore severity. Surgical treatment consisted of transposition of flap into wound defect. This system caused considerable reduction in resolution times. The authors noticed how easily pressure sores arise in the heel region, and how difficultly they heal. This is probably connected with particular anatomical and vascular characteristics of this region.
Characterization of Pressure Fields of Focused Transducers at TÜBİTAK UME
NASA Astrophysics Data System (ADS)
Karaböce, B.; Şahin, A.; İnce, A. T.; Skarlatos, Y.
Field radiated by HIFU (High Intensity Focused Ultrasound) has been investigated by measuring its pressure field and mapping in 2-D and 3-D. A new ultrasound pressure measurement system has been designed and constructed at TÜBİTAK UME (The Scientific and Technological Research Council of Turkey, the National Metrology Institute). System consists of a water tank, positioning system, measurement devices and a controlling program. The hydrophone was attached to a 3-axis, computer-controlled positioning system for alignment with the ultrasound source. The signal was captured and analyzed by the commercially available LabVIEW 8.1 software. The measurements of the ultrasound field were carried out with a needle hydrophone. For each waveform, p, p+ and p-pressures have been calculated. Wave behaviors produced by the KZK model and from experiments look like similar in general. In p, p+, p- the focal point, zero point after the primary peak (focus) and extremum points in the near field well match.
Facility Effect Characterization Test of NASA's HERMeS Hall Thruster
NASA Technical Reports Server (NTRS)
Huang, Wensheng; Kamhawi, Hani; Haag, Thomas W.; Ortega, Alejandro Lopez; Mikellides, Ioannis G.
2016-01-01
A test to characterize the effect of varying background pressure on NASA's 12.5-kW Hall Effect Rocket with Magnetic Shielding had being completed. This thruster is the baseline propulsion system for the Solar Electric Propulsion Technology Demonstration Mission (SEP TDM). Potential differences in thruster performance and oscillation characteristics when in ground facilities versus on-orbit are considered a primary risk for the propulsion system of the Asteroid Redirect Robotic Mission, which is a candidate for SEP TDM. The first primary objective of this test was to demonstrate that the tools being developed to predict the zero-background-pressure behavior of the thruster can provide self-consistent results. The second primary objective of this test was to provide data for refining a physics-based model of the thruster plume that will be used in spacecraft interaction studies. Diagnostics deployed included a thrust stand, Faraday probe, Langmuir probe, retarding potential analyzer, Wien filter spectrometer, and high-speed camera. From the data, a physics-based plume model was refined. Comparisons of empirical data to modeling results are shown.
Schonberger, Robert B.; Burg, Matthew M.; Holt, Natalie; Lukens, Carrie L.; Dai, Feng; Brandt, Cynthia
2011-01-01
Background American College of Cardiology/American Heart Association guidelines describe the perioperative evaluation as “a unique opportunity to identify patients with hypertension,” however factors such as anticipatory stress or medication noncompliance may induce a bias toward higher blood pressure, leaving clinicians unsure about how to interpret preoperative hypertension. Information describing the relationship between preoperative intake blood pressure and primary care measurements could help anesthesiologists make primary care referrals for improved blood pressure control in an evidence-based fashion. We hypothesized that the preoperative examination provides a useful basis for initiating primary care blood pressure referral. Methods We analyzed retrospective data on 2807 patients who arrived from home for surgery and who were subsequently evaluated within 6 months after surgery in the primary care center of the same institution. After descriptive analysis, we conducted multiple linear regression analysis to identify day-of-surgery (DOS) factors associated with subsequent primary care blood pressure. We calculated the sensitivity, specificity, and positive and negative predictive value of different blood pressure referral thresholds using both a single-measurement and a two-stage screen incorporating recent preoperative and DOS measurements for identifying patients with subsequently elevated primary care blood pressure. Results DOS systolic blood pressure (SBP) was higher than subsequent primary care SBP by a mean bias of 5.5mmHg (95% limits of agreement +43.8 to −32.8). DOS diastolic blood pressure (DBP) was higher than subsequent primary care DBP by a mean bias of 1.5mmHg (95% limits of agreement +13.0 to −10.0). Linear regression of DOS factors explained 19% of the variability in primary care SBP and 29% of the variability in DBP. Accounting for the observed bias, a two-stage SBP referral screen requiring preoperative clinic SBP≥140mmHg and DOS SBP≥146mmHg had 95.9% estimated specificity (95% CI 94.4 to 97.0) for identifying subsequent primary care SBP≥140mmHg and estimated sensitivity of 26.8% (95% CI 22.0 to 32.0). A similarly high specificity using a single DOS SBP required a threshold SBP≥160mmHg, for which estimated specificity was 95.2% (95% CI 94.2 to 96.1). For DBP, a presenting DOS DBP≥92mmHg had 95.7% specificity (95% CI 94.8 to 96.4) for subsequent primary care DBP≥90mmHg with a sensitivity of 18.8% (95% CI 14.4 to 24.0). Conclusion A small bias toward higher DOS blood pressures relative to subsequent primary care measurements was observed. DOS factors predicted only a small proportion of the observed variation. Accounting for the observed bias, a two-stage SBP threshold and a single-reading DBP threshold were highly specific though insensitive for identifying subsequent primary care blood pressure elevation. PMID:22075017
Determination of end point of primary drying in freeze-drying process control.
Patel, Sajal M; Doen, Takayuki; Pikal, Michael J
2010-03-01
Freeze-drying is a relatively expensive process requiring long processing time, and hence one of the key objectives during freeze-drying process development is to minimize the primary drying time, which is the longest of the three steps in freeze-drying. However, increasing the shelf temperature into secondary drying before all of the ice is removed from the product will likely cause collapse or eutectic melt. Thus, from product quality as well as process economics standpoint, it is very critical to detect the end of primary drying. Experiments were conducted with 5% mannitol and 5% sucrose as model systems. The apparent end point of primary drying was determined by comparative pressure measurement (i.e., Pirani vs. MKS Baratron), dew point, Lyotrack (gas plasma spectroscopy), water concentration from tunable diode laser absorption spectroscopy, condenser pressure, pressure rise test (manometric temperature measurement or variations of this method), and product thermocouples. Vials were pulled out from the drying chamber using a sample thief during late primary and early secondary drying to determine percent residual moisture either gravimetrically or by Karl Fischer, and the cake structure was determined visually for melt-back, collapse, and retention of cake structure at the apparent end point of primary drying (i.e., onset, midpoint, and offset). By far, the Pirani is the best choice of the methods tested for evaluation of the end point of primary drying. Also, it is a batch technique, which is cheap, steam sterilizable, and easy to install without requiring any modification to the existing dryer.
2003-06-09
KENNEDY SPACE CENTER, FLA. - Members of the STS-114 crew take a look at the Japanese Experiment Module (JEM) pressure module in the Space Station Processing Facility. A research laboratory, the pressurized module is the first element of the JEM, named "Kibo" (Hope), to be delivered to KSC. The National Space Development Agency of Japan (NASDA) developed the laboratory at the Tsukuba Space Center near Tokyo and is Japan's primary contribution to the Station. The JEM also includes an exposed facility (platform) for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.
Experimental Assessment of the Reciprocating Feed System
NASA Technical Reports Server (NTRS)
Eddleman, David E.; Blackmon, James B.; Morton, Christopher D.
2006-01-01
The primary goal of this project was to design, construct, and test a full scale, high pressure simulated propellant feed system test bed that could evaluate the ability of the Reciprocating Feed System (RFS) to provide essentially constant flow rates and pressures to a rocket engine. The two key issues addressed were the effects of the transition of the drain cycle from tank to tank and the benefits of other hardware such as accumulators to provide a constant pressure flow rate out of the RFS. The test bed provided 500 psi flow at rates of the order of those required for engines in the 20,000 lbf thrust class (e.g., 20 to 40 lb/sec). A control system was developed in conjunction with the test article and automated system operation was achieved. Pre-test planning and acceptance activities such as a documented procedure and hazard analysis were conducted and the operation of the test article was approved by, and conducted in coordination with, appropriate NASA Marshall Space Flight Center personnel under a Space Act Agreement. Tests demonstrated successful control of flow rates and pressures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Biraud, S. C.; Reichl, K.
The Greenhouse Gas (GhG) Measurement system is a combination of two systems in series: (1) the Tower Gas Processing (TGP) System, an instrument rack which pulls, pressurizes, and dries air streams from an atmospheric sampling tower through a series of control and monitoring components, and (2) the Picarro model G2301 cavity ringdown spectrometer (CRDS), which measures CO2, CH4, and H2O vapor; the primary measurements of the GhG system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chanchani, J.; Berg, R.R.; Lee, C.I.
1996-09-01
The Upper Cretaceous Austin Chalk is a well known source rock and fractured reservoir in the Gulf Coast. Production is mainly from tectonic fractures, and the mechanism by which oil migrated from the matrix into the fractures is poorly understood. Microfracturing due to oil generation offers a possible explanation for the mechanism of the primary migration of oil in the Austin Chalk. Petrographic study shows that the major components of the primary migration system are the solution seams and the associated microfractures. Pressure solution is manifest as centimeter to millimeter-scale solution seams and smaller microseams. The solution seams are compositesmore » formed by the superposition of the smaller microseams. A significant amount of organic matter was concentrated in the seams along with other insoluble residue. Swarms of horizontal microfractures, many of them filled with calcite and other residue, are associated with the seams. Vertical, tectonic fractures that constitute the reservoir porosity, intersect the solution seams. Pressure solution concentrated organic matter within the solution seams and oil was generated there. It is postulated that the accompanying increase in fluid volume raised the pore pressures and fractured the rock. The newly created microfractures were avenues for migration of fluids from the seams, perhaps by microfracture propagation.« less
Portable Mass Spectrometer Applications for In Situ Environmental Gas Monitoring
NASA Technical Reports Server (NTRS)
Griffin, Timothy P.; Diaz, J. Andres; Arkin, C. Richard; Conejo, Elian
2005-01-01
Primary Goal of this project is to (1) Design/build a flexible system to monitor air contamination (2) Learn requirements for operating system in low pressure and low temperature environments (3) Design/build system for integration into aircraft and automobiles Secondary Goals/Offshoots are (1) Fly aboard different aircraft (2)Hand-carry unit (3) Drive unit in automobiles.
Spark discharge trace element detection system
Adler-Golden, Steven; Bernstein, Lawrence S.; Bien, Fritz
1988-01-01
A spark discharge trace element detection system is provided which includes a spark chamber including a pair of electrodes for receiving a sample of gas to be analyzed at no greater than atmospheric pressure. A voltage is provided across the electrodes for generating a spark in the sample. The intensity of the emitted radiation in at least one primary selected narrow band of the radiation is detected. Each primary band corresponds to an element to be detected in the gas. The intensity of the emission in each detected primary band is integrated during the afterglow time interval of the spark emission and a signal representative of the integrated intensity of the emission in each selected primary bond is utilized to determine the concentration of the corresponding element in the gas.
Spark discharge trace element detection system
Adler-Golden, S.; Bernstein, L.S.; Bien, F.
1988-08-23
A spark discharge trace element detection system is provided which includes a spark chamber including a pair of electrodes for receiving a sample of gas to be analyzed at no greater than atmospheric pressure. A voltage is provided across the electrodes for generating a spark in the sample. The intensity of the emitted radiation in at least one primary selected narrow band of the radiation is detected. Each primary band corresponds to an element to be detected in the gas. The intensity of the emission in each detected primary band is integrated during the afterglow time interval of the spark emission and a signal representative of the integrated intensity of the emission in each selected primary bond is utilized to determine the concentration of the corresponding element in the gas. 12 figs.
NASA Astrophysics Data System (ADS)
Hudoklin, Domen; Drnovšek, Janko
2008-10-01
In the field of hygrometry, a primary dew-point standard can be realized according to several proven principles, such as single-pressure (1-P), two-pressure (2-P), or divided flow. Different realizations have been introduced by various national laboratories, each resulting in a stand-alone complex generation system. Recent trends in generator design favor the single-pressure principle without recirculation because it promises theoretically lower uncertainty and because it avoids problems regarding the leak tightness of the recirculation. Instead of recirculation, the efficiency of saturation, the key factor, is increased by preconditioning the inlet gas entering the saturator. For preconditioning, a presaturator or purifier is used to bring the dew point of the inlet stream close to the saturator temperature. The purpose of the paper is to identify the minimum requirements for the preconditioning system and the main saturator to assure efficient saturation for the LMK generator. Moreover, the aim is also to find out if the preconditioning system can be avoided despite the rather simple construction of the main saturator. If this proves to be the case, the generator design can be simplified while maintaining an accurate value of the generated dew point. Experiments were carried out within the scope of improving our existing primary generator in the above-ambient dew-point range up to +70°C. These results show the generated dew point is within the measurement uncertainty for any dew-point value of the inlet gas. Thus, the preconditioning subsystem can be avoided, which leads to a simplified generator design.
Low-Pressure Long-Term Xenon Storage for Electric Propulsion
NASA Technical Reports Server (NTRS)
Back, Dwight D.; Ramos, Charlie; Meyer, John A.
2001-01-01
This Phase 2 effort demonstrated an alternative Xe storage and regulation system using activated carbon (AC) as a secondary storage media (ACSFR). This regulator system is nonmechanical, simple, inexpensive, and lighter. The ACSFR system isolates the thruster from the compressed gas tank, and allows independent multiple setpoint thruster operation. The flow using an ACSFR can also be throttled by applying increments in electrical power. Primary storage of Xe by AC is not superior to compressed gas storage with regard to weight, but AC storage can provide volume reduction, lower pressures in space, and potentially in situ Xe purification. With partial fill designs, a primary AC storage vessel for Xe could also eliminate problems with two-phase storage and regulate pressure. AC could also be utilized in long-term large quantity storage of Xe serving as a compact capture site for boil-off. Several Xe delivery ACSFR protocols between 2 and 45 sccm, and 15 min to 7 hr, were tested with an average flow variance of 1.2 percent, average power requirements of 5 W, and repeatability s of about 0.4 percent. Power requirements are affected by ACSFR bed sizing and flow rate/ duration design points, and these flow variances can be reduced by optimizing PID controller parameters.
NASA Astrophysics Data System (ADS)
Zhang, L.; Namhata, A.; Dilmore, R. M.; Bromhal, G. S.
2016-12-01
An increasing emphasis on the industrial scale implementation of CO2 storage into geological formations has led to the development of whole-system models to evaluate performance of candidate geologic storage sites, and the environmental risk associated with them. The components of that engineered geologic system include the storage reservoir, primary and secondary seals, and the overlying formations above primary and secondary seals (above-zone monitoring interval, AZMI). Leakage of CO2 and brine through the seal to the AZMI may occur due to the presence of natural or induced fractures in the seal. In this work, an AZMI model that simulates pressure and CO2 saturation responses through time to migration of fluids (here, CO2 and brine) from the primary seal to the AZMI is developed. A hypothetical case is examined wherein CO2 is injected into a storage reservoir for 30 years and a heterogeneous primary seal exists above the reservoir with some permeable zones. The total simulation period is 200 years (30 years of CO2 injection period and 170 years of post CO2 injection period). Key geophysical parameters such as permeability of the AZMI, thickness of the AZMI and porosity of the AZMI have significant impact on pressure evolution in the AZMI. arbitrary Polynomial Chaos (aPC) Expansion analysis shows that permeability of the AZMI has the most significant impact on pressure build up in the AZMI above the injection well at t=200 years, followed by thickness of the AZMI and porosity of the AZMI. Geochemical reactions have no impact on pressure and CO2 saturation evolution in the AZMI during the CO2 injection period. After the CO2 injection stops, precipitation of secondary minerals (e.g., amorphous silica and kaolinite) at the CO2 plume/brine interface in the AZMI formation may cause permeability reduction of the AZMI, which restrains horizontal migration of CO2 in the AZMI.
Modeling of a Sequential Two-Stage Combustor
NASA Technical Reports Server (NTRS)
Hendricks, R. C.; Liu, N.-S.; Gallagher, J. R.; Ryder, R. C.; Brankovic, A.; Hendricks, J. A.
2005-01-01
A sequential two-stage, natural gas fueled power generation combustion system is modeled to examine the fundamental aerodynamic and combustion characteristics of the system. The modeling methodology includes CAD-based geometry definition, and combustion computational fluid dynamics analysis. Graphical analysis is used to examine the complex vortical patterns in each component, identifying sources of pressure loss. The simulations demonstrate the importance of including the rotating high-pressure turbine blades in the computation, as this results in direct computation of combustion within the first turbine stage, and accurate simulation of the flow in the second combustion stage. The direct computation of hot-streaks through the rotating high-pressure turbine stage leads to improved understanding of the aerodynamic relationships between the primary and secondary combustors and the turbomachinery.
Beeckman, Dimitri; Clays, Els; Van Hecke, Ann; Vanderwee, Katrien; Schoonhoven, Lisette; Verhaeghe, Sofie
2013-04-01
Frail older people admitted to nursing homes are at risk of a range of adverse outcomes, including pressure ulcers. Clinical decision support systems are believed to have the potential to improve care and to change the behaviour of healthcare professionals. To determine whether a multi-faceted tailored strategy to implement an electronic clinical decision support system for pressure ulcer prevention improves adherence to recommendations for pressure ulcer prevention in nursing homes. Two-armed randomized controlled trial in a nursing home setting in Belgium. The trial consisted of a 16-week implementation intervention between February and June 2010, including one baseline, four intermediate, and one post-testing measurement. Primary outcome was the adherence to guideline-based care recommendations (in terms of allocating adequate pressure ulcer prevention in residents at risk). Secondary outcomes were the change in resident outcomes (pressure ulcer prevalence) and intermediate outcomes (knowledge and attitudes of healthcare professionals). Random sample of 11 wards (6 experimental; 5 control) in a convenience sample of 4 nursing homes in Belgium. In total, 464 nursing home residents and 118 healthcare professionals participated. The experimental arm was involved in a multi-faceted tailored implementation intervention of a clinical decision support system, including interactive education, reminders, monitoring, feedback and leadership. The control arm received a hard-copy of the pressure ulcer prevention protocol, supported by standardized 30 min group lecture. Patients in the intervention arm were significantly more likely to receive fully adequate pressure ulcer prevention when seated in a chair (F=16.4, P=0.003). No significant improvement was observed on pressure ulcer prevalence and knowledge of the professionals. While baseline attitude scores were comparable between both groups [exp. 74.3% vs. contr. 74.5% (P=0.92)], the mean score after the intervention was 83.5% in the experimental group vs. 72.1% in the control group (F=15.12, P<0.001). The intervention was only partially successful to improve the primary outcome. Attitudes improved significantly while the knowledge of the healthcare workers remained unsatisfactorily low. Further research should focus on the underlying reasons for these findings. Copyright © 2012 Elsevier Ltd. All rights reserved.
Concistrè, A; Grillo, A; La Torre, G; Carretta, R; Fabris, B; Petramala, L; Marinelli, C; Rebellato, A; Fallo, F; Letizia, C
2018-04-01
Primary hyperparathyroidism is associated with a cluster of cardiovascular manifestations, including hypertension, leading to increased cardiovascular risk. The aim of our study was to investigate the ambulatory blood pressure monitoring-derived short-term blood pressure variability in patients with primary hyperparathyroidism, in comparison with patients with essential hypertension and normotensive controls. Twenty-five patients with primary hyperparathyroidism (7 normotensive,18 hypertensive) underwent ambulatory blood pressure monitoring at diagnosis, and fifteen out of them were re-evaluated after parathyroidectomy. Short-term-blood pressure variability was derived from ambulatory blood pressure monitoring and calculated as the following: 1) Standard Deviation of 24-h, day-time and night-time-BP; 2) the average of day-time and night-time-Standard Deviation, weighted for the duration of the day and night periods (24-h "weighted" Standard Deviation of BP); 3) average real variability, i.e., the average of the absolute differences between all consecutive BP measurements. Baseline data of normotensive and essential hypertension patients were matched for age, sex, BMI and 24-h ambulatory blood pressure monitoring values with normotensive and hypertensive-primary hyperparathyroidism patients, respectively. Normotensive-primary hyperparathyroidism patients showed a 24-h weighted Standard Deviation (P < 0.01) and average real variability (P < 0.05) of systolic blood pressure higher than that of 12 normotensive controls. 24-h average real variability of systolic BP, as well as serum calcium and parathyroid hormone levels, were reduced in operated patients (P < 0.001). A positive correlation of serum calcium and parathyroid hormone with 24-h-average real variability of systolic BP was observed in the entire primary hyperparathyroidism patients group (P = 0.04, P = 0.02; respectively). Systolic blood pressure variability is increased in normotensive patients with primary hyperparathyroidism and is reduced by parathyroidectomy, and may potentially represent an additional cardiovascular risk factor in this disease.
New Primary Dew-Point Generators at HMI/FSB-LPM in the Range from -70 °C to +60 °C
NASA Astrophysics Data System (ADS)
Zvizdic, Davor; Heinonen, Martti; Sestan, Danijel
2012-09-01
To extend the dew-point range and to improve the uncertainties of the humidity scale realization at HMI/FSB-LPM, new primary low- and high-range dew-point generators were developed and implemented in cooperation with MIKES, in 2009 through EUROMET Project No. 912. The low-range saturator is designed for primary realization of the dew-point temperature scale from -70 °C to + 5 °C, while the high-range saturator covers the range from 1 °C to 60 °C. The system is designed as a single-pressure, single-pass dew-point generator. MIKES designed and constructed both the saturators to be implemented in dew-point calibration systems at LPM. The LPM took care of purchasing and adapting liquid baths, of implementing the temperature and pressure measurement equipment appropriate for use in the systems, and development of gas preparation and flow control systems as well as of the computer-based automated data acquisition. The principle and the design of the generator are described in detail and schematically depicted. The tests were performed at MIKES to investigate how close both the saturators are to an ideal saturator. Results of the tests show that both the saturators are efficient enough for a primary realization of the dew-point temperature scale from -70 °C to + 60 °C, in the specified flow-rate ranges. The estimated standard uncertainties due to the non-ideal saturation efficiency are between 0.02 °C and 0.05 °C.
Langley Atmospheric Information Retrieval System (LAIRS): System description and user's guide
NASA Technical Reports Server (NTRS)
Boland, D. E., Jr.; Lee, T.
1982-01-01
This document presents the user's guide, system description, and mathematical specifications for the Langley Atmospheric Information Retrieval System (LAIRS). It also includes a description of an optimal procedure for operational use of LAIRS. The primary objective of the LAIRS Program is to make it possible to obtain accurate estimates of atmospheric pressure, density, temperature, and winds along Shuttle reentry trajectories for use in postflight data reduction.
Analysis of BJ493 diesel engine lubrication system properties
NASA Astrophysics Data System (ADS)
Liu, F.
2017-12-01
The BJ493ZLQ4A diesel engine design is based on the primary model of BJ493ZLQ3, of which exhaust level is upgraded to the National GB5 standard due to the improved design of combustion and injection systems. Given the above changes in the diesel lubrication system, its improved properties are analyzed in this paper. According to the structures, technical parameters and indices of the lubrication system, the lubrication system model of BJ493ZLQ4A diesel engine was constructed using the Flowmaster flow simulation software. The properties of the diesel engine lubrication system, such as the oil flow rate and pressure at different rotational speeds were analyzed for the schemes involving large- and small-scale oil filters. The calculated values of the main oil channel pressure are in good agreement with the experimental results, which verifies the proposed model feasibility. The calculation results show that the main oil channel pressure and maximum oil flow rate values for the large-scale oil filter scheme satisfy the design requirements, while the small-scale scheme yields too low main oil channel’s pressure and too high. Therefore, application of small-scale oil filters is hazardous, and the large-scale scheme is recommended.
A Double-Primary Dead-Weight Tester for Pressures (35-175) kPa in Gage Mode.
Jain, Kamlesh; Cen, Yueqin; Bowers, Walter J; Schmidt, James W
2003-01-01
Primary pressure standards in the atmospheric pressure range are often established using mercury manometers. Less frequently, controlled-clearance dead-weight testers in which one component (normally the piston) has been dimensionally measured have also been used. Recent advances in technology on two fronts i) the fabrication of large-diameter pistons and cylinders with good geometry; and ii) the ability to measure the dimensions of these components, have allowed some dead-weight testers at NIST to approach total relative uncertainties (k = 2) in dimensionally-derived effective areas near 5 × 10(-6). This paper describes a single piston/cylinder assembly (NIST-PG201WC/WC) that serves as both a primary gage in which both piston and cylinder are measured dimensionally and a controlled-clearance primary gage (employing the Heydemann-Welch method). Thus it allows some previous assumptions about the modeling of dead-weight testers to be checked. For the gage described in this paper the piston/cylinder clearance obtained from the two analyses have relative differences of 4 × 10(-6) to 7 × 10(-6) over the pressure range 35 kPa to 175 kPa. Some implications of these results will be discussed. From the dimensional characterizations and auxiliary measurements we have determined that the effective area for this gauge at 20 °C is: [Formula: see text]where P is the system pressure and P J is a control pressure. The estimated relative uncertainty in effective area is 8.2 × 10(-6) +1.4 × 10(-11) P/Pa (k = 2). The temperature coefficient for the area was measured and found to be (9.06 ± 0.04) × 10(-6)/K. Thus using the gage at a reference temperature of 23 °C yields an effective area: [Formula: see text]with almost no increase in the uncertainty over that at 20 °C.
Generation of Primary Kilauea Magmas: Constraints on Pressure, Temperature and Composition of Melts
NASA Astrophysics Data System (ADS)
Gudfinnsson, G. H.; Presnall, D. C.
2004-12-01
Picrite glasses from the submarine extension of Kilauea, Puna Ridge, which contain up to 15.0 wt% MgO, are the most magnesian glass samples reported from Hawaii. Their compositions form a distinct olivine fractionation trend. A comparison of this trend with phase relations of garnet lherzolite in the CaO-MgO-Al2O3-SiO2 (CMAS) and CaO-MgO-Al2O3-SiO2-Na2O-FeO (CMASNF) system indicates that melts parental to the Hawaiian picrites are produced by melting of a garnet lherzolite source at a pressure of 5 ± 1 GPa. The primary melt composition for Kilauea proposed by Clague et al. (1995), which has 18.4 wt% MgO, is close to the expected 5 GPa melt composition. By using the pressure-independent CMASNF geothermometer (Gudfinnsson and Presnall, 2001), we obtain a temperature of formation of 1450° C for the most magnesian Puna Ridge glass after correction for the presence of 0.4 wt% H2O and 0.7 wt% CO2. This assumes that the glass is not much modified after separation from the lherzolite source. However, comparison with phase relations in the CMAS system strongly suggests that the most magnesian Puna Ridge glasses are the product of some olivine fractionation, and therefore give temperature considerably lower than that of the source. When applied to the proposed Kilauea primary melt composition of Clague et al. (1995), the CMASNF geothermometer gives a melting temperature of 1596° C or about 1565° C after correction for the presence of volatiles. This compares well with the anhydrous solidus temperature of 1600 ± 15° C at 5 GPa for the fertile KR4003 lherzolite (Lesher et al., 2003), which has the complete garnet lherzolite phase assemblage present at the solidus at this pressure. This consistency supports use of phase relations from the CMAS system and the CMASNF geothermometer to the Puna Ridge picrite compositions. With the pressure and temperature of melting known, one can calculate the potential temperature of the Hawaiian mantle, provided certain conditions are met. The calculation assumes that the temperature at the point of melt segregation is close to the temperature of the solid adiabat. If extensive melting has occurred prior to the segregation, this will be incorrect. Secondly, it is assumed that the melting is occurring at the non-conducting part of the geotherm. Provided this is the case and the Kilauea primary melt composition truly represents a near-primary melt composition, we derive a potential temperature for the mantle beneath Kilauea of about 1500° C. The very high temperature and pressure conditions for magma generation at Hawaii appear to be unmatched by any other currently active volcanism on the Earth. Thus, of all the candidates for plume status, Hawaii appears to be the most robust.
Carbon Dioxide Collection and Purification System for Mars
NASA Technical Reports Server (NTRS)
Clark, D. Larry; Trevathan, Joseph R.
2001-01-01
One of the most abundant resources available on Mars is the atmosphere. The primary constituent, carbon dioxide, can be used to produce a wide variety of consumables including propellants and breathing air. The residual gases can be used for additional pressurization tasks including supplementing the oxygen partial pressure in human habitats. A system is presented that supplies pure, high-pressure carbon dioxide and a separate stream of residual gases ready for further processing. This power-efficient method freezes the carbon dioxide directly from the atmosphere using a pulse-tube cryocooler. The resulting CO2 mass is later thawed in a closed pressure vessel, resulting in a compact source of liquefied gas at the vapor pressure of the bulk fluid. Results from a demonstration system are presented along with analysis and system scaling factors for implementation at larger scales. Trace gases in the Martian atmosphere challenge the system designer for all carbon dioxide acquisitions concepts. The approximately five percent of other gases build up as local concentrations of CO2 are removed, resulting in diminished performance of the collection process. The presented system takes advantage of this fact and draws the concentrated residual gases away as a useful byproduct. The presented system represents an excelient volume and mass solution for collecting and compressing this valuable Martian resource. Recent advances in pulse-tube cryocooler technology have enabled this concept to be realized in a reliable, low power implementation.
A multi-probe thermophoretic soot sampling system for high-pressure diffusion flames
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vargas, Alex M.; Gülder, Ömer L.
Optical diagnostics and physical probing of the soot processes in high pressure combustion pose challenges that are not faced in atmospheric flames. One of the preferred methods of studying soot in atmospheric flames is in situ thermophoretic sampling followed by transmission electron microscopy imaging and analysis for soot sizing and morphology. The application of this method of sampling to high pressures has been held back by various operational and mechanical problems. In this work, we describe a rotating disk multi-probe thermophoretic soot sampling system, driven by a microstepping stepper motor, fitted into a high-pressure chamber capable of producing sooting laminarmore » diffusion flames up to 100 atm. Innovative aspects of the sampling system design include an easy and precise control of the sampling time down to 2.6 ms, avoidance of the drawbacks of the pneumatic drivers used in conventional thermophoretic sampling systems, and the capability to collect ten consecutive samples in a single experimental run. Proof of principle experiments were performed using this system in a laminar diffusion flame of methane, and primary soot diameter distributions at various pressures up to 10 atm were determined. High-speed images of the flame during thermophoretic sampling were recorded to assess the influence of probe intrusion on the flow field of the flame.« less
NASA Technical Reports Server (NTRS)
Huang, W. L.
1980-01-01
The melting relations and distribution of K and Cs in portions of the system was determined at high pressures. Ferrosilite is stable as a primary phase at high pressures because of the incongruent melting of ferrosilite to quartz plus liquid and the boundary between the one and two liquid fields on the joint Fe(1-x) O-FeS-SiO2 shifts away from silica with increasing pressures. Potassium K was found to have limited solubility in metal sulfide liquids at pressures up to 45 kb. The speculation that K may dissolve significantly in metal-metal sulfide liquids after undergoing first order isomorphic transition was tested by determining the distribution of Cs between sulfide and silicate liquids as an analogy to K. At 45 kb, 1400 C and 27 kb, 1300 C only limited amounts of Cs were detected in quench sulfide liquids even at pressures beyond the isomorphic transition of Cs.
Entrainment and mixing in thrust augmenting ejectors
NASA Technical Reports Server (NTRS)
Bernal, L.; Sarohia, V.
1983-01-01
An experimental investigation of two-dimensional thrust augmenting ejector flows has been conducted. Measurements of the shroud surface pressure distribution, mean velocity, turbulent intensities and Reynolds stresses were made in two shroud geometries at various primary nozzle pressure ratios. The effects of shroud geometry and primary nozzle pressure ratio on the shroud surface pressure distribution, mean flow field and turbulent field were determined. From these measurements the evolution of mixing within the shroud of the primary flow and entrained fluid was obtained. The relationship between the mean flow field, the turbulent field and the shroud surface pressure distribution is discussed.
Morgan-Followell, Bethanie; Aylward, Shawn C
2017-03-01
The authors aimed to compare the opening pressures of children with demyelinating disease to children with primary intracranial hypertension. Medical records were reviewed for a primary diagnosis of demyelinating disease, or primary intracranial hypertension. Diagnosis of demyelinating disease was made according to either the 2007 or 2012 International Pediatric Multiple Sclerosis Study Group criteria. Primary intracranial hypertension diagnosis was confirmed by presence of elevated opening pressure, normal cerebrospinal fluid composition and neuroimaging. The authors compared 14 children with demyelinating disease to children with primary intracranial hypertension in 1:1 and 1:2 fashions. There was a statistically significant higher BMI in the primary intracranial hypertension group compared to the demyelinating group ( P = .0203). The mean cerebrospinal fluid white blood cell count was higher in the demyelinating disease group compared to primary intracranial hypertension ( P = .0002). Among both comparisons, the cerebrospinal fluid opening pressure, glucose, protein and red blood cell counts in children with demyelinating disease were comparable to age- and sex-matched controls with primary intracranial hypertension.
Code System to Calculate Tornado-Induced Flow Material Transport.
DOE Office of Scientific and Technical Information (OSTI.GOV)
ANDRAE, R. W.
1999-11-18
Version: 00 TORAC models tornado-induced flows, pressures, and material transport within structures. Its use is directed toward nuclear fuel cycle facilities and their primary release pathway, the ventilation system. However, it is applicable to other structures and can model other airflow pathways within a facility. In a nuclear facility, this network system could include process cells, canyons, laboratory offices, corridors, and offgas systems. TORAC predicts flow through a network system that also includes ventilation system components such as filters, dampers, ducts, and blowers. These ventilation system components are connected to the rooms and corridors of the facility to form amore » complete network for moving air through the structure and, perhaps, maintaining pressure levels in certain areas. The material transport capability in TORAC is very basic and includes convection, depletion, entrainment, and filtration of material.« less
Load leveling on industrial refrigeration systems
NASA Astrophysics Data System (ADS)
Bierenbaum, H. S.; Kraus, A. D.
1982-01-01
A computer model was constructed of a brewery with a 2000 horsepower compressor/refrigeration system. The various conservation and load management options were simulated using the validated model. The savings available for implementing the most promising options were verified by trials in the brewery. Result show that an optimized methodology for implementing load leveling and energy conservation consisted of: (1) adjusting (or tuning) refrigeration systems controller variables to minimize unnecessary compressor starts, (2) The primary refrigeration system operating parameters, compressor suction pressure, and discharge pressure are carefully controlled (modulated) to satisfy product quality constraints (as well as in-process material cooling rates and temperature levels) and energy evaluating the energy cost savings associated with reject heat recovery, and (4) a decision is made to implement the reject heat recovery system based on a cost/benefits analysis.
The F-SCAN system of foot pressure analysis.
Young, C R
1993-07-01
The age of computerized gait analysis is here. There are several systems available to meet the needs of the podiatric practitioner. This author believes that the F-SCAN technology system makes a significant contribution to the practice of podiatric medicine. The system is user friendly, accurate, reproducible, and affordable. Its graphic display capabilities are colorfully attractive and easily understood. The primary focus of the F-SCAN system is that of peak pressure distribution over time. Vertical plantar pressure dispersion across the plantar surface of the foot is recorded, processed, and graphically displayed in terms of sequential gait changes. The system further allows for the manipulation of the accumulated data to present it in a more comprehensive manner. Future updates on the F-SCAN software are already close at hand and are expected to enhance the diagnostic capabilities of the system further. The four primary areas of clinical application for F-SCAN have been identified and briefly discussed. The recognition of certain biomechanical abnormalities, monitoring preorthotic and postorthotic use, evaluation of the diabetic or neuropathic foot, and presurgical and postsurgical functional examinations constitute this group. The F-SCAN system largely helps to remove some of the unavoidable guess work from essential diagnostic and therapeutic procedures. As we increase our understanding of the pathomechanics of these clinical problems, so too will we improve our management of the associated complications. Years ago, at the time when computerized gait analysis was being introduced to the podiatric profession, a frequently asked question was: What does it tell me that I don't already know or can't see by watching the patient walk?(ABSTRACT TRUNCATED AT 250 WORDS)
On-line detection of key radionuclides for fuel-rod failure in a pressurized water reactor.
Qin, Guoxiu; Chen, Xilin; Guo, Xiaoqing; Ni, Ning
2016-08-01
For early on-line detection of fuel rod failure, the key radionuclides useful in monitoring must leak easily from failing rods. Yield, half-life, and mass share of fission products that enter the primary coolant also need to be considered in on-line analyses. From all the nuclides that enter the primary coolant during fuel-rod failure, (135)Xe and (88)Kr were ultimately chosen as crucial for on-line monitoring of fuel-rod failure. A monitoring system for fuel-rod failure detection for pressurized water reactor (PWR) based on the LaBr3(Ce) detector was assembled and tested. The samples of coolant from the PWR were measured using the system as well as a HPGe γ-ray spectrometer. A comparison showed the method was feasible. Finally, the γ-ray spectra of primary coolant were measured under normal operations and during fuel-rod failure. The two peaks of (135)Xe (249.8keV) and (88)Kr (2392.1keV) were visible, confirming that the method is capable of monitoring fuel-rod failure on-line. Copyright © 2016 Elsevier Ltd. All rights reserved.
INITIAL ASSESSMENT OF SURFACE PRESSURE CHARACTERISTICS OF TWO ROTARY WING UAV DESIGNS
NASA Technical Reports Server (NTRS)
Jones, Henry E.; Wong, Oliver D.; Watkins, A. Neal; Noonan, Kevin W.; Reis, Deane G.; Malovrh, Brendon D.; Ingram, Joanne L.
2006-01-01
This paper presents results of an experimental investigation of two rotary-wing UAV designs. The primary goal of the investigation was to provide a set of interactional aerodynamic data for an emerging class of rotorcraft. The present paper provides an overview of the test and an introduction to the test articles, and instrumentation. Sample data in the form of fixed system pressure coefficient response to changes in configuration attitude and flight condition for both rotor off and on conditions are presented. The presence of the rotor is seen to greatly affect the magnitude of the response. Pressure coefficients were measured using both conventional pressure taps and via pressure sensitive paint. Comparisons between the two methods are presented and demonstrate that the pressure sensitive paint is a promising method; however, further work on the technique is required.
Development and Preliminary Feasibility of an Automated Hypertension Self-Management System.
Irizarry, Taya; Allen, Matthew; Suffoletto, Brian P; Einhorn, Julian; Burke, Lora E; Kamarck, Thomas W; Rollman, Bruce L; Muldoon, Matthew F
2018-05-25
Uncontrolled hypertension constitutes a significant challenge throughout the world. Blood pressure measurement by patients is informative for both patients and providers, but is rarely performed systematically, thereby reducing its utility. Mobile phones can be used to efficiently prompt individuals to measure blood pressure and automate data management while avoiding technology barriers to widespread adoption. Presented is the design and pilot test results of MyBP, an automated texting intervention to support blood pressure self-monitoring and patient self-management. Three sequential phases are described: 1) stakeholders' needs assessment, 2) preliminary design pilot (n=10), and 3) a six-week pilot of the re-designed comprehensive program with hypertensive patients (n=43) recruited from three clinical sites (Emergency Department, Primary Care, Hypertension Center). Outcomes of interest included, participant adherence, perceived importance of blood pressure monitoring and healthy behavior change. Median adherence to MyBP prompts over six weeks was 79% (72% Emergency Department, 84% Primary Care and 96% Hypertension Center, H(2)=5.56, p=0.06). Adherence did not vary by age, gender, education or baseline use of texting, but was lowest among patients recruited from the Emergency Department (χ(2) 2 =6.66, p=0.04). In the exit survey, MyBP was associated with increased importance of blood pressure self-monitoring and particularly motivated primary care and emergency department groups to improve dietary habits, increase daily physical activity and focus on stress reduction. The majority of participants (88%) indicated interest in using the program for 6 months. Automated mobile-phone based blood pressure self-monitoring using MyBP is feasible, acceptable and scalable, and may improve self-management and support clinical care. Copyright © 2018. Published by Elsevier Inc.
Jet fuel based high pressure solid oxide fuel cell system
NASA Technical Reports Server (NTRS)
Gummalla, Mallika (Inventor); Yamanis, Jean (Inventor); Olsommer, Benoit (Inventor); Dardas, Zissis (Inventor); Bayt, Robert (Inventor); Srinivasan, Hari (Inventor); Dasgupta, Arindam (Inventor); Hardin, Larry (Inventor)
2013-01-01
A power system for an aircraft includes a solid oxide fuel cell system which generates electric power for the aircraft and an exhaust stream; and a heat exchanger for transferring heat from the exhaust stream of the solid oxide fuel cell to a heat requiring system or component of the aircraft. The heat can be transferred to fuel for the primary engine of the aircraft. Further, the same fuel can be used to power both the primary engine and the SOFC. A heat exchanger is positioned to cool reformate before feeding to the fuel cell. SOFC exhaust is treated and used as inerting gas. Finally, oxidant to the SOFC can be obtained from the aircraft cabin, or exterior, or both.
Jet Fuel Based High Pressure Solid Oxide Fuel Cell System
NASA Technical Reports Server (NTRS)
Srinivasan, Hari (Inventor); Hardin, Larry (Inventor); Gummalla, Mallika (Inventor); Yamanis, Jean (Inventor); Olsommer, Benoit (Inventor); Dardas, Zissis (Inventor); Dasgupta, Arindam (Inventor); Bayt, Robert (Inventor)
2015-01-01
A power system for an aircraft includes a solid oxide fuel cell system which generates electric power for the aircraft and an exhaust stream; and a heat exchanger for transferring heat from the exhaust stream of the solid oxide fuel cell to a heat requiring system or component of the aircraft. The heat can be transferred to fuel for the primary engine of the aircraft. Further, the same fuel can be used to power both the primary engine and the SOFC. A heat exchanger is positioned to cool reformate before feeding to the fuel cell. SOFC exhaust is treated and used as inerting gas. Finally, oxidant to the SOFC can be obtained from the aircraft cabin, or exterior, or both.
A TEMPO-free copper-catalyzed aerobic oxidation of alcohols.
Xu, Boran; Lumb, Jean-Philip; Arndtsen, Bruce A
2015-03-27
The copper-catalyzed aerobic oxidation of primary and secondary alcohols without an external N-oxide co-oxidant is described. The catalyst system is composed of a Cu/diamine complex inspired by the enzyme tyrosinase, along with dimethylaminopyridine (DMAP) or N-methylimidazole (NMI). The Cu catalyst system works without 2,2,6,6-tetramethyl-l-piperidinoxyl (TEMPO) at ambient pressure and temperature, and displays activity for un-activated secondary alcohols, which remain a challenging substrate for catalytic aerobic systems. Our work underscores the importance of finding alternative mechanistic pathways for alcohol oxidation, which complement Cu/TEMPO systems, and demonstrate, in this case, a preference for the oxidation of activated secondary over primary alcohols. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Space shuttle EVA/IVA support equipment requirements study. Volume 1: Final summary report
NASA Technical Reports Server (NTRS)
1973-01-01
A study was conducted to determine the support equipment requirements for space shuttle intravehicular and extravehicular activities. The subjects investigated are; (1) EVA/IVA task identification and analysis,. (2) primary life support system, (3) emergency life support system, (4) pressure suit assembly, (5) restraints, (6) work site provision, (7) emergency internal vehicular emergencies, and (8) vehicular interfaces.
Pressure measurements on a rectangular wing with a NACA0012 airfoil during conventional flutter
NASA Technical Reports Server (NTRS)
Rivera, Jose A., Jr.; Dansberry, Bryan E.; Durham, Michael H.; Bennett, Robert M.; Silva, Walter A.
1992-01-01
The Structural Dynamics Division at NASA LaRC has started a wind tunnel activity referred to as the Benchmark Models Program. The primary objective of the program is to acquire measured dynamic instability and corresponding pressure data that will be useful for developing and evaluating aeroelastic type CFD codes currently in use or under development. The program is a multi-year activity that will involve testing of several different models to investigate various aeroelastic phenomena. The first model consisted of a rigid semispan wing having a rectangular planform and a NACA 0012 airfoil shape which was mounted on a flexible two degree-of-freedom mount system. Two wind-tunnel tests were conducted with the first model. Several dynamic instability boundaries were investigated such as a conventional flutter boundary, a transonic plunge instability region near Mach = 0.90, and stall flutter. In addition, wing surface unsteady pressure data were acquired along two model chords located at the 60 to 95-percent span stations during these instabilities. At this time, only the pressure data for the conventional flutter boundary is presented. The conventional flutter boundary and the wing surface unsteady pressure measurements obtained at the conventional flutter boundary test conditions in pressure coefficient form are presented. Wing surface steady pressure measurements obtained with the model mount system rigidized are also presented. These steady pressure data were acquired at essentially the same dynamic pressure at which conventional flutter had been encountered with the mount system flexible.
HIF isoforms in the skin differentially regulate systemic arterial pressure
Cowburn, Andrew S.; Takeda, Norihiko; Boutin, Adam T.; Kim, Jung-Whan; Sterling, Jane C.; Nakasaki, Manando; Southwood, Mark; Goldrath, Ananda W.; Jamora, Colin; Nizet, Victor; Chilvers, Edwin R.; Johnson, Randall S.
2013-01-01
Vascular flow through tissues is regulated via a number of homeostatic mechanisms. Localized control of tissue blood flow, or autoregulation, is a key factor in regulating tissue perfusion and oxygenation. We show here that the net balance between two hypoxia-inducible factor (HIF) transcription factor isoforms, HIF-1α and HIF-2α, is an essential mechanism regulating both local and systemic blood flow in the skin of mice. We also show that balance of HIF isoforms in keratinocyte-specific mutant mice affects thermal adaptation, exercise capacity, and systemic arterial pressure. The two primary HIF isoforms achieve these effects in opposing ways that are associated with HIF isoform regulation of nitric oxide production. We also show that a correlation exists between altered levels of HIF isoforms in the skin and the degree of idiopathic hypertension in human subjects. Thus, the balance between HIF-1α and HIF-2α expression in keratinocytes is a control element of both tissue perfusion and systemic arterial pressure, with potential implications in human hypertension. PMID:24101470
Neuroregulation of a chemosensitive afferent system in the canine distal esophagus.
Sandler, A D; Schlegel, J F; DeSautel, M G; Maher, J W
1993-10-01
Systemic and local responses mediated by chemonociceptive receptors located in the mucosa of the canine distal esophagus were examined following stimulation with capsaicin (8-methyl-N-vanillyl-6-nonenamide). The neural pathways and neurotransmitters mediating these sensory responses were also investigated. Topical application of capsaicin solution to the distal esophageal mucosa produced significant increases in lower esophageal sphincter pressure (LESP), mean arterial pressure (MAP), pulse rate (PR), and respiratory rate (RR) (P < 0.01). Pretreatment with tetrodotoxin completely abolished this reflex activity. Following truncal vagotomy and pyloroplasty, topical capsaicin application produced an increase in LESP, but the increases in MAP, PR, and RR were blocked. The initial increase in LESP was blocked by hexamethonium, atropine, and 4-diphenylacetoxy-N-methylpiperidine, but was not inhibited by phentolamine. Excitatory cardiovascular responses were inhibited by hexamethonium. Administration of a Substance P antagonist attenuated both local and systemic responses. These studies suggest that the vagus nerves serve as the primary afferent pathways through which chemonociceptive esophageal stimuli can induce cardiovascular and respiratory reflex excitation. The increase in lower esophageal sphincter pressure in response to mucosal capsaicin stimulation is mediated via an intrinsic neural pathway that functions independently of vagal innervation, but is dependent on both cholinergic ganglionic neurotransmission and muscarinic type 2 smooth muscle receptor excitation. Substance P appears to play a role in primary sensory afferents as a chemonociceptive neurotransmitter in the canine distal esophagus.
Direct-heating solar-collector dump valve
NASA Technical Reports Server (NTRS)
Howikman, T. C.
1977-01-01
Five-port ganged valve isolates collector from primary load system pressure and drains collectors, allowing use of direct heating with all its advantages. Valve is opened and closed by same switch that controls pump or by temperature sensor set at O C, while providing direct dump option.
Pupils Today: Greater Stress and Frustrations.
ERIC Educational Resources Information Center
Neuber, Manfred, Ed.
1988-01-01
This article reports on a survey of West German elementary and secondary school students undertaken to discover their opinions of the West German educational system. Their primary criticism was directed toward: (1) scholastic performance pressure; (2) unrealistic learning objectives; and (3) unsympathetic teachers. Older students were more…
Energy balance during underwater implosion of ductile metallic cylinders.
Chamberlin, Ryan E; Guzas, Emily L; Ambrico, Joseph M
2014-11-01
Energy-based metrics are developed and applied to a numerical test case of implosion of an underwater pressure vessel. The energy metrics provide estimates of the initial energy in the system (potential energy), the energy released into the fluid as a pressure pulse, the energy absorbed by the imploding structure, and the energy absorbed by air trapped within the imploding structure. The primary test case considered is the implosion of an aluminum cylinder [diameter: 2.54 cm (1 in.), length: 27.46 cm (10.81 in.)] that collapses flat in a mode-2 shape with minimal fracture. The test case indicates that the structure absorbs the majority (92%) of the initial energy in the system. Consequently, the energy emitted as a pressure pulse into the fluid is a small fraction, approximately 5%, of the initial energy. The energy absorbed by the structure and the energy emitted into the fluid are calculated for additional simulations of underwater pressure vessel implosions. For all cases investigated, there is minimal fracture in the collapse, the structure absorbs more than 80% of the initial energy of the system, and the released pressure pulse carries away less than 6% of the initial energy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wichman, K.; Tsao, J.; Mayfield, M.
The regulatory application of leak before break (LBB) for operating and advanced reactors in the U.S. is described. The U.S. Nuclear Regulatory Commission (NRC) has approved the application of LBB for six piping systems in operating reactors: reactor coolant system primary loop piping, pressurizer surge, safety injection accumulator, residual heat removal, safety injection, and reactor coolant loop bypass. The LBB concept has also been applied in the design of advanced light water reactors. LBB applications, and regulatory considerations, for pressurized water reactors and advanced light water reactors are summarized in this paper. Technology development for LBB performed by the NRCmore » and the International Piping Integrity Research Group is also briefly summarized.« less
McManus, Richard J; Mant, Jonathan; Franssen, Marloes; Nickless, Alecia; Schwartz, Claire; Hodgkinson, James; Bradburn, Peter; Farmer, Andrew; Grant, Sabrina; Greenfield, Sheila M; Heneghan, Carl; Jowett, Susan; Martin, Una; Milner, Siobhan; Monahan, Mark; Mort, Sam; Ogburn, Emma; Perera-Salazar, Rafael; Shah, Syed Ahmar; Yu, Ly-Mee; Tarassenko, Lionel; Hobbs, F D Richard
2018-03-10
Studies evaluating titration of antihypertensive medication using self-monitoring give contradictory findings and the precise place of telemonitoring over self-monitoring alone is unclear. The TASMINH4 trial aimed to assess the efficacy of self-monitored blood pressure, with or without telemonitoring, for antihypertensive titration in primary care, compared with usual care. This study was a parallel randomised controlled trial done in 142 general practices in the UK, and included hypertensive patients older than 35 years, with blood pressure higher than 140/90 mm Hg, who were willing to self-monitor their blood pressure. Patients were randomly assigned (1:1:1) to self-monitoring blood pressure (self-montoring group), to self-monitoring blood pressure with telemonitoring (telemonitoring group), or to usual care (clinic blood pressure; usual care group). Randomisation was by a secure web-based system. Neither participants nor investigators were masked to group assignment. The primary outcome was clinic measured systolic blood pressure at 12 months from randomisation. Primary analysis was of available cases. The trial is registered with ISRCTN, number ISRCTN 83571366. 1182 participants were randomly assigned to the self-monitoring group (n=395), the telemonitoring group (n=393), or the usual care group (n=394), of whom 1003 (85%) were included in the primary analysis. After 12 months, systolic blood pressure was lower in both intervention groups compared with usual care (self-monitoring, 137·0 [SD 16·7] mm Hg and telemonitoring, 136·0 [16·1] mm Hg vs usual care, 140·4 [16·5]; adjusted mean differences vs usual care: self-monitoring alone, -3·5 mm Hg [95% CI -5·8 to -1·2]; telemonitoring, -4·7 mm Hg [-7·0 to -2·4]). No difference between the self-monitoring and telemonitoring groups was recorded (adjusted mean difference -1·2 mm Hg [95% CI -3·5 to 1·2]). Results were similar in sensitivity analyses including multiple imputation. Adverse events were similar between all three groups. Self-monitoring, with or without telemonitoring, when used by general practitioners to titrate antihypertensive medication in individuals with poorly controlled blood pressure, leads to significantly lower blood pressure than titration guided by clinic readings. With most general practitioners and many patients using self-monitoring, it could become the cornerstone of hypertension management in primary care. National Institute for Health Research via Programme Grant for Applied Health Research (RP-PG-1209-10051), Professorship to RJM (NIHR-RP-R2-12-015), Oxford Collaboration for Leadership in Applied Health Research and Care, and Omron Healthcare UK. Copyright © 2018 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.
Electromagnetic Pumps for Conductive-Propellant Feed Systems
NASA Technical Reports Server (NTRS)
Markusic, Thomas E.; Polzin, Kurt A.; Dehoyos, Amado
2005-01-01
Prototype electromagnetic pumps for use with lithium and bismuth propellants were constructed and tested. Such pumps may be used to pressurize future electric propulsion liquid metal feed systems, with the primary advantages being the compactness and simplicity versus alternative pressurization technologies. Design details for two different pumps are described: the first was designed to withstand (highly corrosive) lithium propellant, and t he second was designed to tolerate the high temperature required to pump liquid bismuth. Both qualitative and quantitative test results are presented. Open-loop tests demonstrated the capability of each device to electromagnetically pump its design propellant (lithium or bismuth). A second set of tests accurately quantified the pump pressure developed as a function of current. These experiments, which utilized a more easily handled material (gallium), demonstrated continuously-adjustable pump pressure levels ranging from 0-100 Torr for corresponding input current levels of 0-75 A. While the analysis and testing in this study specifically targeted lithium and bismuth propellants, the underlying design principles should be useful in implementing liquid metal pumps in any conductive-propellant feed system.
Performance Charts for a Turbojet System
NASA Technical Reports Server (NTRS)
Karp, Irving M.
1947-01-01
Convenient charts are presented for computing the thrust, fuel consumption, and other performance values of a turbojet system. These charts take into account the effects of ram pressure, compressor pressure ratio, ratio of combustion-chamber-outlet temperature to atmospheric temperature, compressor efficiency, turbine efficiency, combustion efficiency, discharge-nozzle coefficient, losses in total pressure in the inlet to the jet-propulsion unit and in the combustion chamber, and variation in specific heats with temperature. The principal performance charts show clearly the effects of the primary variables and correction charts provide the effects of the secondary variables. The performance of illustrative cases of turbojet systems is given. It is shown that maximum thrust per unit mass rate of air flow occurs at a lower compressor pressure ratio than minimum specific fuel consumption. The thrust per unit mass rate of air flow increases as the combustion-chamber discharge temperature increases. For minimum specific fuel consumption, however, an optimum combustion-chamber discharge temperature exists, which in some cases may be less than the limiting temperature imposed by the strength temperature characteristics of present materials.
Carter, Brittany U; Kaylor, Mary Beth
2016-04-01
Hypertension is the most commonly diagnosed medical condition in the USA. Unfortunately, patients are misdiagnosed in primary care because of inaccurate office-based blood pressure measurements. Several US healthcare organizations currently recommend confirming an office-based hypertension diagnosis with ambulatory blood pressure monitoring to avoid overtreatment; however, its use for the purpose of confirming an office-based hypertension diagnosis is relatively unknown. This descriptive study surveyed 143 primary-care physicians in Oregon with regard to their current use of ambulatory blood pressure monitoring. Nineteen percent of the physicians reported that they would use ambulatory blood pressure monitoring to confirm an office-based hypertension diagnosis, although over half had never ordered it. The most frequent indication for ordering ambulatory blood pressure monitoring was to investigate suspected white-coat hypertension (37.3%). In addition, many of the practices did not own an ambulatory blood pressure monitoring device (79.7%) and, therefore, had to refer patients to other clinics or departments for testing. Many primary-care physicians will need to change their current clinical practice to align with the shift toward a confirmation process for office-based hypertension diagnoses to improve population health.
Large scale cryogenic fluid systems testing
NASA Technical Reports Server (NTRS)
1992-01-01
NASA Lewis Research Center's Cryogenic Fluid Systems Branch (CFSB) within the Space Propulsion Technology Division (SPTD) has the ultimate goal of enabling the long term storage and in-space fueling/resupply operations for spacecraft and reusable vehicles in support of space exploration. Using analytical modeling, ground based testing, and on-orbit experimentation, the CFSB is studying three primary categories of fluid technology: storage, supply, and transfer. The CFSB is also investigating fluid handling, advanced instrumentation, and tank structures and materials. Ground based testing of large-scale systems is done using liquid hydrogen as a test fluid at the Cryogenic Propellant Tank Facility (K-site) at Lewis' Plum Brook Station in Sandusky, Ohio. A general overview of tests involving liquid transfer, thermal control, pressure control, and pressurization is given.
Tablet PC Enabled Body Sensor System for Rural Telehealth Applications
Panicker, Nitha V.; Kumar, A. Sukesh
2016-01-01
Telehealth systems benefit from the rapid growth of mobile communication technology for measuring physiological signals. Development and validation of a tablet PC enabled noninvasive body sensor system for rural telehealth application are discussed in this paper. This system includes real time continuous collection of physiological parameters (blood pressure, pulse rate, and temperature) and fall detection of a patient with the help of a body sensor unit and wireless transmission of the acquired information to a tablet PC handled by the medical staff in a Primary Health Center (PHC). Abnormal conditions are automatically identified and alert messages are given to the medical officer in real time. Clinical validation is performed in a real environment and found to be successful. Bland-Altman analysis is carried out to validate the wrist blood pressure sensor used. The system works well for all measurements. PMID:26884757
Field Test of a Three-Channel Seismic Event Discriminator
1975-03-01
vault contains three corner piers, in addition to the primary central pier. Using the corner piers, a pair of 19-foot long-period mercury tiltmeters ...seismometers were the sensors used in testing the seismic event- discriminator system. The recording equipment consisted of an eight- channel pressure
Combat Vehicle Cooling/Heating Design Investigation.
1981-09-01
pressure side of the condensing heat exchanger to obtain proper water removal and turbine inlet conditions. The primary heat exchanger is used to limit boot ...Detroit, Michigan; May 1955. 8. "Development of a Refrigeration System for Lunar Surface and Spacesuit Applications" Report No. T122-RP-046
2003-08-12
KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility can be seen the U.S. Node 2 (at left) and the Japanese Experiment Module (JEM)’s Pressurized Module (at right). The Italian-built Node 2, the second of three Space Station connecting modules, attaches to the end of the U.S. Lab and will provide attach locations for the Japanese laboratory, European laboratory, the Centrifuge Accommodation Module and, later, Multipurpose Logistics Modules. It will provide the primary docking location for the Shuttle when a pressurized mating adapter is attached to Node 2. Installation of the module will complete the U.S. Core of the ISS. Node 2 is the designated payload for mission STS-120. No orbiter or launch date has been determined yet. The Pressurized Module is the first element of the JEM to be delivered to KSC. The JEM is Japan's primary contribution to the Station. It will enhance the unique research capabilities of the orbiting complex by providing an additional environment for astronauts to conduct science experiments. The JEM also includes an exposed facility (platform) for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.
Pressure-relieving properties of a intra-operative warming device.
Baker, E A; Leaper, D J
2003-04-01
The primary objective of this study was to determine differences in interface pressure between four mattress combinations: a standard operating table mattress, a pressure-relieving gel pad and an under-patient warming device set at 38 degrees C (Pegasus Inditherm System) and at ambient temperature. The secondary objective was to determine whether the warming device remains stable in extreme surgical positions. Interface pressures obtained with all four combinations were measured in 10 healthy volunteers using force sensing array technology. The warming device demonstrated better or equivalent pressure relief when compared with the standard gel pad. There was no significant difference in subject position 'shift' between the mattress, the gel pad and the warming device for either the Trendelenberg or reverse Trendelenberg positions. Both pressure-relieving mattresses and warming reduce intra-operative pressure damage. A mattress with both properties may further reduce pressure damage postoperatively. The warming device used in this study appears stable--subject 'slippage' was minimal in extreme positions. Research needs to be conducted among real anaesthetised patients to support these conclusions.
The effect of process parameters on Twin Wire Arc spray pattern shape
Hall, Aaron Christopher; McCloskey, James Francis; Horner, Allison Lynne
2015-04-20
A design of experiments approach was used to describe process parameter—spray pattern relationships in the Twin Wire Arc process using zinc feed stock in a TAFA 8835 (Praxair, Concord, NH, USA) spray torch. Specifically, the effects of arc current, primary atomizing gas pressure, and secondary atomizing gas pressure on spray pattern size, spray pattern flatness, spray pattern eccentricity, and coating deposition rate were investigated. Process relationships were investigated with the intent of maximizing or minimizing each coating property. It was determined that spray pattern area was most affected by primary gas pressure and secondary gas pressure. Pattern eccentricity was mostmore » affected by secondary gas pressure. Pattern flatness was most affected by primary gas pressure. Lastly, coating deposition rate was most affected by arc current.« less
The effect of process parameters on Twin Wire Arc spray pattern shape
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hall, Aaron Christopher; McCloskey, James Francis; Horner, Allison Lynne
A design of experiments approach was used to describe process parameter—spray pattern relationships in the Twin Wire Arc process using zinc feed stock in a TAFA 8835 (Praxair, Concord, NH, USA) spray torch. Specifically, the effects of arc current, primary atomizing gas pressure, and secondary atomizing gas pressure on spray pattern size, spray pattern flatness, spray pattern eccentricity, and coating deposition rate were investigated. Process relationships were investigated with the intent of maximizing or minimizing each coating property. It was determined that spray pattern area was most affected by primary gas pressure and secondary gas pressure. Pattern eccentricity was mostmore » affected by secondary gas pressure. Pattern flatness was most affected by primary gas pressure. Lastly, coating deposition rate was most affected by arc current.« less
NASA Astrophysics Data System (ADS)
Salminen, J.; Högström, R.; Saxholm, S.; Lakka, A.; Riski, K.; Heinonen, M.
2018-04-01
In this paper we present the development of a primary standard for dynamic pressures that is based on the drop weight method. At the moment dynamic pressure transducers are typically calibrated using reference transducers, which are calibrated against static pressure standards. Because dynamic and static characteristics of pressure transducers may significantly differ from each other, it is important that these transducers are calibrated against dynamic pressure standards. In a method developed in VTT Technical Research Centre of Finland Ltd, Centre for Metrology MIKES, a pressure pulse is generated by impact between a dropping weight and a piston of a liquid-filled piston-cylinder assembly. The traceability to SI-units is realized through interferometric measurement of the acceleration of the dropping weight during impact, the effective area of the piston-cylinder assembly and the mass of the weight. Based on experimental validation and an uncertainty evaluation, the developed primary standard provides traceability for peak pressures in the range from 10 MPa to 400 MPa with a few millisecond pulse width and a typical relative expanded uncertainty (k = 2) of 1.5%. The performance of the primary standard is demonstrated by test calibrations of two dynamic pressure transducers.
The Brain Melanocortin System, Sympathetic Control, and Obesity Hypertension
do Carmo, Jussara M.; Wang, Zhen; Hall, John E.
2014-01-01
Excess weight gain is the most significant, preventable cause of increased blood pressure (BP) in patients with primary (essential) hypertension and increases the risk for cardiovascular and renal diseases. In this review, we discuss the role of the brain melanocortin system in causing increased sympathetic activity in obesity and other forms of hypertension. In addition, we highlight potential mechanisms by which the brain melanocortin system modulates metabolic and cardiovascular functions. PMID:24789984
Vacuum chamber with a supersonic flow aerodynamic window
Hanson, Clark L.
1982-01-01
A supersonic flow aerodynamic window, whereby a steam ejector situated in a primary chamber at vacuum exhausts superheated steam toward an orifice to a region of higher pressure, creating a barrier to the gas in the region of higher pressure which attempts to enter through the orifice. In a mixing chamber outside and in fluid communication with the primary chamber, superheated steam and gas are combined into a mixture which then enters the primary chamber through the orifice. At the point of impact of the ejector/superheated steam and the incoming gas/superheated steam mixture, a barrier is created to the gas attempting to enter the ejector chamber. This barrier, coupled with suitable vacuum pumping means and cooling means, serves to keep the steam ejector and primary chamber at a negative pressure, even though the primary chamber has an orifice to a region of higher pressure.
Vacuum chamber with a supersonic-flow aerodynamic window
Hanson, C.L.
1980-10-14
A supersonic flow aerodynamic window is disclosed whereby a steam ejector situated in a primary chamber at vacuum exhausts superheated steam toward an orifice to a region of higher pressure, creating a barrier to the gas in the region of higher pressure which attempts to enter through the orifice. In a mixing chamber outside and in fluid communication with the primary chamber, superheated steam and gas are combined into a mixture which then enters the primary chamber through the orifice. At the point of impact of the ejector/superheated steam and the incoming gas/superheated steam mixture, a barrier is created to the gas attempting to enter the ejector chamber. This barrier, coupled with suitable vacuum pumping means and cooling means, serves to keep the steam ejector and primary chamber at a negative pressure, even though the primary chamber has an orifice to a region of higher pressure.
Ajay, Vamadevan S; Jindal, Devraj; Roy, Ambuj; Venugopal, Vidya; Sharma, Rakshit; Pawar, Abha; Kinra, Sanjay; Tandon, Nikhil; Prabhakaran, Dorairaj
2016-12-21
The high burden of undetected and undertreated hypertension and diabetes mellitus is a major health challenge worldwide. The mPower Heart Project aimed to develop and test a feasible and scalable intervention for hypertension and diabetes mellitus by task-sharing with the use of a mobile phone-based clinical decision support system at Community Health Centers in Himachal Pradesh, India. The development of the intervention and mobile phone-based clinical decision support system was carried out using mixed methods in five Community Health Centers. The intervention was subsequently evaluated using pre-post evaluation design. During intervention, a nurse care coordinator screened, examined, and entered patient parameters into mobile phone-based clinical decision support system to generate a prescription, which was vetted by a physician. The change in systolic blood pressure, diastolic blood pressure, and fasting plasma glucose (FPG) over 18 months of intervention was quantified using generalized estimating equations models. During intervention, 6797 participants were enrolled. Six thousand sixteen participants had hypertension (mean systolic blood pressure: 146.1 mm Hg, 95% CI: 145.7, 146.5; diastolic blood pressure: 89.52 mm Hg, 95% CI: 89.33, 89.72), of which 3152 (52%) subjects were newly detected. Similarly, 1516 participants had diabetes mellitus (mean FPG: 177.9 mg/dL, 95% CI: 175.8, 180.0), of which 450 (30%) subjects were newly detected. The changes in systolic blood pressure, diastolic blood pressure, and FPG observed at 18 months of follow-up were -14.6 mm Hg (95% CI: -15.3, -13.8), -7.6 mm Hg (CI: -8.0, -7.2), and -50.0 mg/dL (95% CI: -54.6, -45.5), respectively, and were statistically significant even after adjusting for age, sex, and Community Health Center. A nurse-facilitated, mobile phone-based clinical decision support system-enabled intervention in primary care was associated with improvements in blood pressure and blood glucose control and has the potential to scale-up in resource poor settings. URL: https://www.clinicaltrials.gov. Unique identifiers: NCT01794052. Clinical Trial Registry-India: CTRI/2013/02/003412. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
2003-06-06
KENNEDY SPACE CENTER, FLA. - The container with the Japanese Experiment Module (JEM)’s pressurized module is inside the Space Station Processing Facility. The National Space Development Agency of Japan (NASDA) developed the laboratory at the Tsukuba Space Center near Tokyo. The Pressurized Module is the first element of the JEM, named "Kibo" (Hope), to be delivered to KSC. The JEM is Japan's primary contribution to the Station. It will enhance the unique research capabilities of the orbiting complex by providing an additional environment for astronauts to conduct science experiments. The JEM also includes an exposed facility (platform) for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.
2003-06-04
KENNEDY SPACE CENTER, FLA. - The truck transporting the Pressurized Module of the Japanese Experiment Module (JEM) to KSC’s Space Station Processing Facility arrives on Center. The National Space Development Agency of Japan (NASDA) developed the laboratory at the Tsukuba Space Center near Tokyo. The Pressurized Module is the first element of the JEM, named "Kibo" (Hope), to be delivered to KSC. The JEM is Japan's primary contribution to the Station. It will enhance the unique research capabilities of the orbiting complex by providing an additional environment for astronauts to conduct science experiments. The JEM also includes an exposed facility (platform) for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.
2003-05-30
KENNEDY SPACE CENTER, FLA. - The JEM Pressurized Module is seen in the hold of the ship that carried it from Japan. The National Space Development Agency of Japan (NASDA) built the laboratory at the Tsukuba Space Center near Tokyo. The Pressurized Module is the first element of the JEM, Japan’s primary contribution to the space station, to be delivered to KSC. It will enhance the unique research capabilities of the orbiting complex by providing an additional shirt-sleeve environment for astronauts to conduct science experiments. The JEM also includes two logistics modules, an exposed pallet for space environment experiments and a robotic manipulator system that are still under construction in Japan. The various JEM components will be assembled in space over the course of three space shuttle missions.
Approach for Mitigating Pressure Garment Design Risks in a Mobile Lunar Surface Systems Architecture
NASA Technical Reports Server (NTRS)
Aitchison, Lindsay
2009-01-01
The stated goals of the 2004 Vision for Space Exploration focus on establishing a human presence throughout the solar system beginning with the establishment of a permanent human presence on the Moon. However, the precise objectives to be accomplished on the lunar surface and the optimal system architecture to achieve those objectives have been a topic of much debate since the inception of the Constellation Program. There are two basic styles of system architectures being traded at the Programmatic level: a traditional large outpost that would focus on techniques for survival off our home planet and a greater depth of exploration within one area, or a mobile approach- akin to a series of nomadic camps- that would allow greater breadth of exploration opportunities. The traditional outpost philosophy is well within the understood pressure garment design space with respect to developing interfaces and operational life cycle models. The mobile outpost, however, combines many unknowns with respect to pressure garment performance and reliability that could dramatically affect the cost and schedule risks associated with the Constellation space suit system. This paper provides an overview of the concepts being traded for a mobile architecture from the operations and hardware implementation perspective, describes the primary risks to the Constellation pressure garment associated with each of the concepts, and summarizes the approach necessary to quantify the pressure garment design risks to enable the Constellation Program to make informed decisions when deciding on an overall lunar surface systems architecture.
Investigations of primary blast-induced traumatic brain injury
NASA Astrophysics Data System (ADS)
Sawyer, T. W.; Josey, T.; Wang, Y.; Villanueva, M.; Ritzel, D. V.; Nelson, P.; Lee, J. J.
2018-01-01
The development of an advanced blast simulator (ABS) has enabled the reproducible generation of single-pulse shock waves that simulate free-field blast with high fidelity. Studies with rodents in the ABS demonstrated the necessity of head restraint during head-only exposures. When the head was not restrained, violent global head motion was induced by pressures that would not produce similar movement of a target the size and mass of a human head. This scaling artefact produced changes in brain function that were reminiscent of traumatic brain injury (TBI) due to impact-acceleration effects. Restraint of the rodent head eliminated these, but still produced subtle changes in brain biochemistry, showing that blast-induced pressure waves do cause brain deficits. Further experiments were carried out with rat brain cell aggregate cultures that enabled the conduct of studies without the gross movement encountered when using rodents. The suspension nature of this model was also exploited to minimize the boundary effects that complicate the interpretation of primary blast studies using surface cultures. Using this system, brain tissue was found not only to be sensitive to pressure changes, but also able to discriminate between the highly defined single-pulse shock waves produced by underwater blast and the complex pressure history exposures experienced by aggregates encased within a sphere and subjected to simulated air blast. The nature of blast-induced primary TBI requires a multidisciplinary research approach that addresses the fidelity of the blast insult, its accurate measurement and characterization, as well as the limitations of the biological models used.
Slag processing system for direct coal-fired gas turbines
Pillsbury, Paul W.
1990-01-01
Direct coal-fired gas turbine systems and methods for their operation are provided by this invention. The gas turbine system includes a primary zone for burning coal in the presence of compressed air to produce hot combustion gases and debris, such as molten slag. The turbine system further includes a secondary combustion zone for the lean combustion of the hot combustion gases. The operation of the system is improved by the addition of a cyclone separator for removing debris from the hot combustion gases. The cyclone separator is disposed between the primary and secondary combustion zones and is in pressurized communication with these zones. In a novel aspect of the invention, the cyclone separator includes an integrally disposed impact separator for at least separating a portion of the molten slag from the hot combustion gases.
Independent Orbiter Assessment (IOA): Analysis of the elevon subsystem
NASA Technical Reports Server (NTRS)
Wilson, R. E.; Riccio, J. R.
1986-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results for the Orbiter Elevon system hardware. The elevon actuators are located at the trailing edge of the wing surface. The proper function of the elevons is essential during the dynamic flight phases of ascent and entry. In the ascent phase of flight, the elevons are used for relieving high wing loads. For entry, the elevons are used to pitch and roll the vehicle. Specifically, the elevon system hardware comprises the following components: flow cutoff valve; switching valve; electro-hydraulic (EH) servoactuator; secondary delta pressure transducer; bypass valve; power valve; power valve check valve; primary actuator; primary delta pressure transducer; and primary actuator position transducer. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode. Of the 25 failure modes analyzed, 18 were determined to be PCIs.
Braun, C; Lang, C; Hocher, B; Gretz, N; van der Woude, F J; Rohmeiss, P
1997-01-01
The renal endothelin (ET) system has been claimed to play an important role in the regulation of renal blood flow (RBF) and sodium excretion in primary hypertension. The aim of the present study was to investigate the contribution of the endogenous ET system in the autoregulation of total RBF, cortical blood flow (CBF), pressure-dependent plasma renin activity (PRA) and pressure natriuresis in spontaneously hypertensive rats (SHR) by means of the combined (A/B) ET-receptor antagonist, bosentan. In anesthetized rats, RBF was measured by transit-time flow probes and CBF by laser flow probes. During the experiments, the rats received an intrarenal infusion of either bosentan (1 mg/kg/h) or vehicle. Renal perfusion pressure (RPP) was lowered in pressure steps of 5 mm Hg with a servo-controlled electropneumatic device via an inflatable suprarenal cuff. Bosentan had no effect on resting RPP, CBF, PRA and renal sodium excretion, whereas RBF was lowered by 30% (p < 0.05). Furthermore after bosentan the rats revealed a complete loss of RBF autoregulation. In contrast no changes in autoregulation of CBF, pressure-dependent PRA and pressure natriuresis were observed. Our findings demonstrate a significant impairment in total RBF autoregulatory ability during renal ET-receptor blockade which is not confined to the cortical vessels. These data suggest that the renal ET system plays an important role in the dynamic regulation of renal blood flow in SHR.
Ehret, Georg B; Ferreira, Teresa; Chasman, Daniel I; Jackson, Anne U; Schmidt, Ellen M; Johnson, Toby; Thorleifsson, Gudmar; Luan, Jian'an; Donnelly, Lousie A; Kanoni, Stavroula; Petersen, Ann-Kristin; Pihur, Vasyl; Strawbridge, Rona J; Shungin, Dmitry; Hughes, Maria F; Meirelles, Osorio; Kaakinen, Marika; Bouatia-Naji, Nabila; Kristiansson, Kati; Shah, Sonia; Kleber, Marcus E; Guo, Xiuqing; Lyytikäinen, Leo-Pekka; Fava, Cristiano; Eriksson, Niclas; Nolte, Ilja M; Magnusson, Patrik K; Salfati, Elias L; Rallidis, Loukianos S; Theusch, Elizabeth; Smith, Andrew J P; Folkersen, Lasse; Witkowska, Kate; Pers, Tune H; Joehanes, Roby; Kim, Stuart K; Lataniotis, Lazaros; Jansen, Rick; Johnson, Andrew D; Warren, Helen; Kim, Young Jin; Zhao, Wei; Wu, Ying; Tayo, Bamidele O; Bochud, Murielle; Absher, Devin; Adair, Linda S; Amin, Najaf; Arking, Dan E; Axelsson, Tomas; Baldassarre, Damiano; Balkau, Beverley; Bandinelli, Stefania; Barnes, Michael R; Barroso, Inês; Bevan, Stephen; Bis, Joshua C; Bjornsdottir, Gyda; Boehnke, Michael; Boerwinkle, Eric; Bonnycastle, Lori L; Boomsma, Dorret I; Bornstein, Stefan R; Brown, Morris J; Burnier, Michel; Cabrera, Claudia P; Chambers, John C; Chang, I-Shou; Cheng, Ching-Yu; Chines, Peter S; Chung, Ren-Hua; Collins, Francis S; Connell, John M; Döring, Angela; Dallongeville, Jean; Danesh, John; de Faire, Ulf; Delgado, Graciela; Dominiczak, Anna F; Doney, Alex S F; Drenos, Fotios; Edkins, Sarah; Eicher, John D; Elosua, Roberto; Enroth, Stefan; Erdmann, Jeanette; Eriksson, Per; Esko, Tonu; Evangelou, Evangelos; Evans, Alun; Fall, Tove; Farrall, Martin; Felix, Janine F; Ferrières, Jean; Ferrucci, Luigi; Fornage, Myriam; Forrester, Terrence; Franceschini, Nora; Duran, Oscar H Franco; Franco-Cereceda, Anders; Fraser, Ross M; Ganesh, Santhi K; Gao, He; Gertow, Karl; Gianfagna, Francesco; Gigante, Bruna; Giulianini, Franco; Goel, Anuj; Goodall, Alison H; Goodarzi, Mark O; Gorski, Mathias; Gräßler, Jürgen; Groves, Christopher; Gudnason, Vilmundur; Gyllensten, Ulf; Hallmans, Göran; Hartikainen, Anna-Liisa; Hassinen, Maija; Havulinna, Aki S; Hayward, Caroline; Hercberg, Serge; Herzig, Karl-Heinz; Hicks, Andrew A; Hingorani, Aroon D; Hirschhorn, Joel N; Hofman, Albert; Holmen, Jostein; Holmen, Oddgeir Lingaas; Hottenga, Jouke-Jan; Howard, Phil; Hsiung, Chao A; Hunt, Steven C; Ikram, M Arfan; Illig, Thomas; Iribarren, Carlos; Jensen, Richard A; Kähönen, Mika; Kang, Hyun; Kathiresan, Sekar; Keating, Brendan J; Khaw, Kay-Tee; Kim, Yun Kyoung; Kim, Eric; Kivimaki, Mika; Klopp, Norman; Kolovou, Genovefa; Komulainen, Pirjo; Kooner, Jaspal S; Kosova, Gulum; Krauss, Ronald M; Kuh, Diana; Kutalik, Zoltan; Kuusisto, Johanna; Kvaløy, Kirsti; Lakka, Timo A; Lee, Nanette R; Lee, I-Te; Lee, Wen-Jane; Levy, Daniel; Li, Xiaohui; Liang, Kae-Woei; Lin, Honghuang; Lin, Li; Lindström, Jaana; Lobbens, Stéphane; Männistö, Satu; Müller, Gabriele; Müller-Nurasyid, Martina; Mach, François; Markus, Hugh S; Marouli, Eirini; McCarthy, Mark I; McKenzie, Colin A; Meneton, Pierre; Menni, Cristina; Metspalu, Andres; Mijatovic, Vladan; Moilanen, Leena; Montasser, May E; Morris, Andrew D; Morrison, Alanna C; Mulas, Antonella; Nagaraja, Ramaiah; Narisu, Narisu; Nikus, Kjell; O'Donnell, Christopher J; O'Reilly, Paul F; Ong, Ken K; Paccaud, Fred; Palmer, Cameron D; Parsa, Afshin; Pedersen, Nancy L; Penninx, Brenda W; Perola, Markus; Peters, Annette; Poulter, Neil; Pramstaller, Peter P; Psaty, Bruce M; Quertermous, Thomas; Rao, Dabeeru C; Rasheed, Asif; Rayner, N William N W R; Renström, Frida; Rettig, Rainer; Rice, Kenneth M; Roberts, Robert; Rose, Lynda M; Rossouw, Jacques; Samani, Nilesh J; Sanna, Serena; Saramies, Jouko; Schunkert, Heribert; Sebert, Sylvain; Sheu, Wayne H-H; Shin, Young-Ah; Sim, Xueling; Smit, Johannes H; Smith, Albert V; Sosa, Maria X; Spector, Tim D; Stančáková, Alena; Stanton, Alice; Stirrups, Kathleen E; Stringham, Heather M; Sundstrom, Johan; Swift, Amy J; Syvänen, Ann-Christine; Tai, E-Shyong; Tanaka, Toshiko; Tarasov, Kirill V; Teumer, Alexander; Thorsteinsdottir, Unnur; Tobin, Martin D; Tremoli, Elena; Uitterlinden, Andre G; Uusitupa, Matti; Vaez, Ahmad; Vaidya, Dhananjay; van Duijn, Cornelia M; van Iperen, Erik P A; Vasan, Ramachandran S; Verwoert, Germaine C; Virtamo, Jarmo; Vitart, Veronique; Voight, Benjamin F; Vollenweider, Peter; Wagner, Aline; Wain, Louise V; Wareham, Nicholas J; Watkins, Hugh; Weder, Alan B; Westra, Harm-Jan; Wilks, Rainford; Wilsgaard, Tom; Wilson, James F; Wong, Tien Y; Yang, Tsun-Po; Yao, Jie; Yengo, Loic; Zhang, Weihua; Zhao, Jing Hua; Zhu, Xiaofeng; Bovet, Pascal; Cooper, Richard S; Mohlke, Karen L; Saleheen, Danish; Lee, Jong-Young; Elliott, Paul; Gierman, Hinco J; Willer, Cristen J; Franke, Lude; Hovingh, G Kees; Taylor, Kent D; Dedoussis, George; Sever, Peter; Wong, Andrew; Lind, Lars; Assimes, Themistocles L; Njølstad, Inger; Schwarz, Peter Eh; Langenberg, Claudia; Snieder, Harold; Caulfield, Mark J; Melander, Olle; Laakso, Markku; Saltevo, Juha; Rauramaa, Rainer; Tuomilehto, Jaakko; Ingelsson, Erik; Lehtimäki, Terho; Hveem, Kristian; Palmas, Walter; März, Winfried; Kumari, Meena; Salomaa, Veikko; Chen, Yii-Der I; Rotter, Jerome I; Froguel, Philippe; Jarvelin, Marjo-Riitta; Lakatta, Edward G; Kuulasmaa, Kari; Franks, Paul W; Hamsten, Anders; Wichmann, H-Erich; Palmer, Colin N A; Stefansson, Kari; Ridker, Paul M; Loos, Ruth J F; Chakravarti, Aravinda; Deloukas, Panos; Morris, Andrew P; Newton-Cheh, Christopher; Munroe, Patricia B
2016-10-01
To dissect the genetic architecture of blood pressure and assess effects on target organ damage, we analyzed 128,272 SNPs from targeted and genome-wide arrays in 201,529 individuals of European ancestry, and genotypes from an additional 140,886 individuals were used for validation. We identified 66 blood pressure-associated loci, of which 17 were new; 15 harbored multiple distinct association signals. The 66 index SNPs were enriched for cis-regulatory elements, particularly in vascular endothelial cells, consistent with a primary role in blood pressure control through modulation of vascular tone across multiple tissues. The 66 index SNPs combined in a risk score showed comparable effects in 64,421 individuals of non-European descent. The 66-SNP blood pressure risk score was significantly associated with target organ damage in multiple tissues but with minor effects in the kidney. Our findings expand current knowledge of blood pressure-related pathways and highlight tissues beyond the classical renal system in blood pressure regulation.
Chasman, Daniel I.; Jackson, Anne U.; Schmidt, Ellen M.; Johnson, Toby; Thorleifsson, Gudmar; Luan, Jian'an; Donnelly, Lousie A.; Kanoni, Stavroula; Petersen, Ann-Kristin; Pihur, Vasyl; Strawbridge, Rona J.; Shungin, Dmitry; Hughes, Maria F.; Meirelles, Osorio; Kaakinen, Marika; Bouatia-Naji, Nabila; Kristiansson, Kati; Shah, Sonia; Kleber, Marcus E.; Guo, Xiuqing; Lyytikäinen, Leo-Pekka; Fava, Cristiano; Eriksson, Niclas; Nolte, Ilja M.; Magnusson, Patrik K.; Salfati, Elias L.; Rallidis, Loukianos S.; Theusch, Elizabeth; Smith, Andrew J.P.; Folkersen, Lasse; Witkowska, Kate; Pers, Tune H.; Joehanes, Roby; Kim, Stuart K.; Lataniotis, Lazaros; Jansen, Rick; Johnson, Andrew D.; Warren, Helen; Kim, Young Jin; Zhao, Wei; Wu, Ying; Tayo, Bamidele O.; Bochud, Murielle; Absher, Devin; Adair, Linda S.; Amin, Najaf; Arking, Dan E.; Axelsson, Tomas; Baldassarre, Damiano; Balkau, Beverley; Bandinelli, Stefania; Barnes, Michael R.; Barroso, Inês; Bevan, Stephen; Bis, Joshua C.; Bjornsdottir, Gyda; Boehnke, Michael; Boerwinkle, Eric; Bonnycastle, Lori L.; Boomsma, Dorret I.; Bornstein, Stefan R.; Brown, Morris J.; Burnier, Michel; Cabrera, Claudia P.; Chambers, John C.; Chang, I-Shou; Cheng, Ching-Yu; Chines, Peter S.; Chung, Ren-Hua; Collins, Francis S.; Connell, John M.; Döring, Angela; Dallongeville, Jean; Danesh, John; de Faire, Ulf; Delgado, Graciela; Dominiczak, Anna F.; Doney, Alex S.F.; Drenos, Fotios; Edkins, Sarah; Eicher, John D.; Elosua, Roberto; Enroth, Stefan; Erdmann, Jeanette; Eriksson, Per; Esko, Tonu; Evangelou, Evangelos; Evans, Alun; Fall, Tove; Farrall, Martin; Felix, Janine F.; Ferrières, Jean; Ferrucci, Luigi; Fornage, Myriam; Forrester, Terrence; Franceschini, Nora; Duran, Oscar H. Franco; Franco-Cereceda, Anders; Fraser, Ross M.; Ganesh, Santhi K.; Gao, He; Gertow, Karl; Gianfagna, Francesco; Gigante, Bruna; Giulianini, Franco; Goel, Anuj; Goodall, Alison H.; Goodarzi, Mark O.; Gorski, Mathias; Gräßler, Jürgen; Groves, Christopher; Gudnason, Vilmundur; Gyllensten, Ulf; Hallmans, Göran; Hartikainen, Anna-Liisa; Hassinen, Maija; Havulinna, Aki S.; Hayward, Caroline; Hercberg, Serge; Herzig, Karl-Heinz; Hicks, Andrew A.; Hingorani, Aroon D.; Hirschhorn, Joel N.; Hofman, Albert; Holmen, Jostein; Holmen, Oddgeir Lingaas; Hottenga, Jouke-Jan; Howard, Phil; Hsiung, Chao A.; Hunt, Steven C.; Ikram, M. Arfan; Illig, Thomas; Iribarren, Carlos; Jensen, Richard A.; Kähönen, Mika; Kang, Hyun; Kathiresan, Sekar; Keating, Brendan J.; Khaw, Kay-Tee; Kim, Yun Kyoung; Kim, Eric; Kivimaki, Mika; Klopp, Norman; Kolovou, Genovefa; Komulainen, Pirjo; Kooner, Jaspal S.; Kosova, Gulum; Krauss, Ronald M.; Kuh, Diana; Kutalik, Zoltan; Kuusisto, Johanna; Kvaløy, Kirsti; Lakka, Timo A; Lee, Nanette R.; Lee, I-Te; Lee, Wen-Jane; Levy, Daniel; Li, Xiaohui; Liang, Kae-Woei; Lin, Honghuang; Lin, Li; Lindström, Jaana; Lobbens, Stéphane; Männistö, Satu; Müller, Gabriele; Müller-Nurasyid, Martina; Mach, François; Markus, Hugh S.; Marouli, Eirini; McCarthy, Mark I.; McKenzie, Colin A.; Meneton, Pierre; Menni, Cristina; Metspalu, Andres; Mijatovic, Vladan; Moilanen, Leena; Montasser, May E.; Morris, Andrew D.; Morrison, Alanna C.; Mulas, Antonella; Nagaraja, Ramaiah; Narisu, Narisu; Nikus, Kjell; O'Donnell, Christopher J.; O'Reilly, Paul F.; Ong, Ken K.; Paccaud, Fred; Palmer, Cameron D.; Parsa, Afshin; Pedersen, Nancy L.; Penninx, Brenda W.; Perola, Markus; Peters, Annette; Poulter, Neil; Pramstaller, Peter P.; Psaty, Bruce M.; Quertermous, Thomas; Rao, Dabeeru C.; Rasheed, Asif; Rayner, N William N.W.R.; Renström, Frida; Rettig, Rainer; Rice, Kenneth M.; Roberts, Robert; Rose, Lynda M.; Rossouw, Jacques; Samani, Nilesh J.; Sanna, Serena; Saramies, Jouko; Schunkert, Heribert; Sebert, Sylvain; Sheu, Wayne H.-H.; Shin, Young-Ah; Sim, Xueling; Smit, Johannes H.; Smith, Albert V.; Sosa, Maria X.; Spector, Tim D.; Stančáková, Alena; Stanton, Alice; Stirrups, Kathleen E.; Stringham, Heather M.; Sundstrom, Johan; Swift, Amy J.; Syvänen, Ann-Christine; Tai, E-Shyong; Tanaka, Toshiko; Tarasov, Kirill V.; Teumer, Alexander; Thorsteinsdottir, Unnur; Tobin, Martin D.; Tremoli, Elena; Uitterlinden, Andre G.; Uusitupa, Matti; Vaez, Ahmad; Vaidya, Dhananjay; van Duijn, Cornelia M.; van Iperen, Erik P.A.; Vasan, Ramachandran S.; Verwoert, Germaine C.; Virtamo, Jarmo; Vitart, Veronique; Voight, Benjamin F.; Vollenweider, Peter; Wagner, Aline; Wain, Louise V.; Wareham, Nicholas J.; Watkins, Hugh; Weder, Alan B.; Westra, Harm-Jan; Wilks, Rainford; Wilsgaard, Tom; Wilson, James F.; Wong, Tien Y.; Yang, Tsun-Po; Yao, Jie; Yengo, Loic; Zhang, Weihua; Zhao, Jing Hua; Zhu, Xiaofeng; Bovet, Pascal; Cooper, Richard S.; Mohlke, Karen L.; Saleheen, Danish; Lee, Jong-Young; Elliott, Paul; Gierman, Hinco J.; Willer, Cristen J.; Franke, Lude; Hovingh, G Kees; Taylor, Kent D.; Dedoussis, George; Sever, Peter; Wong, Andrew; Lind, Lars; Assimes, Themistocles L.; Njølstad, Inger; Schwarz, Peter EH.; Langenberg, Claudia; Snieder, Harold; Caulfield, Mark J.; Melander, Olle; Laakso, Markku; Saltevo, Juha; Rauramaa, Rainer; Tuomilehto, Jaakko; Ingelsson, Erik; Lehtimäki, Terho; Hveem, Kristian; Palmas, Walter; März, Winfried; Kumari, Meena; Salomaa, Veikko; Chen, Yii-Der I.; Rotter, Jerome I.; Froguel, Philippe; Jarvelin, Marjo-Riitta; Lakatta, Edward G.; Kuulasmaa, Kari; Franks, Paul W.; Hamsten, Anders; Wichmann, H.-Erich; Palmer, Colin N.A.; Stefansson, Kari; Ridker, Paul M; Loos, Ruth J.F.; Chakravarti, Aravinda; Deloukas, Panos; Morris, Andrew P.; Newton-Cheh, Christopher; Munroe, Patricia B.
2016-01-01
To dissect the genetic architecture of blood pressure and assess effects on target-organ damage, we analyzed 128,272 SNPs from targeted and genome-wide arrays in 201,529 individuals of European ancestry and genotypes from an additional 140,886 individuals were used for validation. We identified 66 blood pressure loci, of which 17 were novel and 15 harbored multiple distinct association signals. The 66 index SNPs were enriched for cis-regulatory elements, particularly in vascular endothelial cells, consistent with a primary role in blood pressure control through modulation of vascular tone across multiple tissues. The 66 index SNPs combined in a risk score showed comparable effects in 64,421 individuals of non-European descent. The 66-SNP blood pressure risk score was significantly associated with target-organ damage in multiple tissues, with minor effects in the kidney. Our findings expand current knowledge of blood pressure pathways and highlight tissues beyond the classic renal system in blood pressure regulation. PMID:27618452
METHOD OF CHEMICAL DECONTAMINATION OF STAINLESS STEEL NUCLEAR FACILITIES
Pancer, G.P.; Zegger, J.L.
1961-12-19
A chemical method is given for removing activated corrosion products on the primary system surfaces of a pressurized water reactor. The corrosion product deposits are composed chiefly of magnetite (Fe/sub 3/O/sub 4/) with small amounts of nickel and chromium oxides. The corroded surfaces are first flushed with a caustic permanganate primary solution consisting of sodium hydroxide and potassium permanganate followed by a secondary rinse solution of ammonium citrate and citric acid containing the complexing agent Versene in small amounts. Demineralized water is used to clean out the primary and secondary solutions and a 60-minute drying period precedes the rinse solution. (AEC)
46 CFR 56.15-5 - Fluid-conditioner fittings.
Code of Federal Regulations, 2012 CFR
2012-10-01
... allowable working pressure does not exceed one-fourth of the burst pressure or produce a primary stress... of the burst pressure or produce a primary stress greater than one-fifth of the ultimate tensile... representative model to a proof test or experimental stress analysis described in paragraph A-22 of Section I of...
46 CFR 56.15-5 - Fluid-conditioner fittings.
Code of Federal Regulations, 2011 CFR
2011-10-01
... allowable working pressure does not exceed one-fourth of the burst pressure or produce a primary stress... of the burst pressure or produce a primary stress greater than one-fifth of the ultimate tensile... representative model to a proof test or experimental stress analysis described in paragraph A-22 of Section I of...
46 CFR 56.15-5 - Fluid-conditioner fittings.
Code of Federal Regulations, 2013 CFR
2013-10-01
... allowable working pressure does not exceed one-fourth of the burst pressure or produce a primary stress... of the burst pressure or produce a primary stress greater than one-fifth of the ultimate tensile... representative model to a proof test or experimental stress analysis described in paragraph A-22 of section I of...
46 CFR 56.15-5 - Fluid-conditioner fittings.
Code of Federal Regulations, 2014 CFR
2014-10-01
... allowable working pressure does not exceed one-fourth of the burst pressure or produce a primary stress... of the burst pressure or produce a primary stress greater than one-fifth of the ultimate tensile... representative model to a proof test or experimental stress analysis described in paragraph A-22 of section I of...
Rubin, P C; Curzio, J L; Kelman, A; Elliott, H L; Reid, J L
1984-01-01
Experience over two years with 376 hypertensive patients managed at a clinic where the primary observations are made by a trained nurse, clinical information is held on a microprocessor, and treatment follows a standard stepped care approach has been assessed. Blood pressure control after both one and two years was appreciably improved, with over 70% of patients having diastolic pressure below 90 mm Hg compared with 22% of patients when they first attended the new clinic. The non-attendance rate was half that of the conventional hospital outpatient clinic. A computer based record system with a nurse run hypertension clinic is acceptable to patients and offers the possibility of more effective long term control of blood pressure in large numbers of patients. PMID:6432180
Climatology of the autumn Red Sea trough
NASA Astrophysics Data System (ADS)
Awad, Adel M.; Mashat, Abdul-Wahab S.
2018-03-01
In this study, the Sudan low and the associated Red Sea trough (RST) are objectively identified using the mean sea level pressure (SLP) data from the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis dataset covering the period 1955-2015. The Sudan low was detected in approximately 60.6% of the autumn periods, and approximately 83% of the detected low-pressure systems extended into RSTs, with most generated at night and during cold months. The distribution of the RSTs demonstrated that Sudan, South Sudan and Red Sea are the primary development areas of the RSTs, generating 97% of the RSTs in the study period. In addition, the outermost areas affected by RSTs, which include the southern, central and northern Red Sea areas, received approximately 91% of the RSTs originating from the primary generation areas. The synoptic features indicated that a Sudan low developed into an RST when the Sudan low deepened in the atmosphere, while the low pressures over the southern Arabian Peninsula are shallow and the anticyclonic systems are weakened over the northern Red Sea. Moreover, stabile areas over Africa and Arabian Peninsula form a high stability gradient around the Red Sea and the upper maximum winds weaken. The results of the case studies indicate that RSTs extend northward when the upper cyclonic and anticyclonic systems form a high geopotential gradient over Arabian Peninsula. Furthermore, the RST is oriented from the west to the east when the Azores high extends eastward and the Siberian high shrinks eastward or shifts northward.
Development of a condenser for the dual catalyst water recovery system
NASA Technical Reports Server (NTRS)
Budinikas, P.; Rasouli, F.; Rabadi, N.
1983-01-01
Conceptual evaporation/condensation systems suitable for integration with the catalytic water recovery method were evaluated. The primary requirements for each concept were its capability to operate under zero-gravity conditions, condense recovered water from a vapor-noncondensable gas mixture, and integrate with the catalytic system. Specific energy requirements were estimated for concepts meeting the primary requirements, and the concept most suitable for integration with the catalytic system was proposed. A three-man rate condenser capable of integration with the proposed system, condensing water vapor in presence of noncondensables and transferring the heat of condensation to feed urine was designed, fabricated, and tested. It was treated with steam/air mixtures at atmospheric and elevated pressures and integrated with an actual catalytic water recovery system. The condenser has a condensation efficiency exceeding 90% and heat transfer rate of approximately 85% of theoretical value at coolant temperature ranging from 7 to 80 deg C.
Role of pressure-sensitive adhesives in transdermal drug delivery systems.
Lobo, Shabbir; Sachdeva, Sameer; Goswami, Tarun
2016-01-01
Transdermal drug delivery systems (TDDS) are employed for the delivery of drugs across skin into the systemic circulation. Pressure-sensitive adhesive (PSA) is one of the most critical components used in a TDDS. The primary function of PSA is to help in adhesion of patch to skin, but more importantly it acts as a matrix for the drug and other excipients. Hence, apart from adhesion of the patch, PSA also affects other critical quality attributes of the TDDS such as drug delivery, flux through skin and physical and chemical stability of the finished product. This review article provides a summary of the adhesives used in various types of TDDS. In particular, this review will cover the design types of TDDS, categories of PSAs and their evaluation and regulatory aspects.
User's Manual for FSLIP-3, FLEXSTAB Loads Integration Program
NASA Technical Reports Server (NTRS)
Sims, R. L.
1981-01-01
The FSLIP program documentation and user's manual is presented. As a follow on program to the FLEXSTAB computer analysis system, the primary function of this FORTRAN IV program is to integrate panel pressure coefficients computed by FLEXSTAB to obtain total shear, bending, and torque airloads on various surfaces, summed relative to user specified axes. The program essentially replaces the ALOADS module in FLEXSTAB with expanded capabilities and flexibility. As such, FSLIP is generalized to work on any FLEXSTAB model or other pressure data if in a compatible format.
PWR PRELIMINARY DESIGN FOR PL-3
DOE Office of Scientific and Technical Information (OSTI.GOV)
Humphries, G. E.
1962-02-28
The pressurized water reactor preliminary design, the preferred design developed under Phase I of the PL-3 contract, is presented. Plant design criteria, summary of plant selection, plant description, reactor and primary system description, thermal and hydraulic analysis, nuclear analysis, control and instrumentatlon description, shielding description, auxiliary systems, power plant equipment, waste dispusal, buildings and tunnels, services, operation and maintenance, logistics, erection, cost information, and a training program outline are given. (auth)
Oho, Eisaku; Suzuki, Kazuhiko; Yamazaki, Sadao
2007-01-01
The quality of the image signal obtained from the environmental secondary electron detector (ESED) employed in a variable pressure (VP) SEM can be dramatically improved by using helium gas. The signal-to-noise ratio (SNR) increases gradually in the range of the pressures that can be used in our modified SEM. This method is especially useful in low-voltage VP SEM as well as in a variety of SEM operating conditions, because helium gas can more or less maintain the amount of unscattered primary electrons. In order to measure the SNR precisely, a digital scan generator system for obtaining two images with identical views is employed as a precondition.
Space shuttle system program definition. Volume 2: Technical report
NASA Technical Reports Server (NTRS)
1972-01-01
The Phase B Extension of the Space Shuttle System Program Definition study was redirected to apply primary effort to consideration of space shuttle systems utilizing either recoverable pressure fed liquids or expendable solid rocket motor boosters. Two orbiter configurations were to be considered, one with a 15x60 foot payload bay with a 65,000 lb, due East, up-payload capability and the other with a 14x45 payload bay with 45,000 lb, of due East, up-payload. Both were to use three SSME engines with 472,000 lb of vacuum thrust each. Parallel and series burn ascent modes were to be considered for the launch configurations of primary interest. A recoverable pump-fed booster is included in the study in a series burn configuration with the 15x60 orbiter. To explore the potential of the swing engine orbiter configuration in the pad abort case, it is included in the study matrix in two launch configurations, a series burn pressure fed BRB and a parallel burn SRM. The resulting matrix of configuration options is shown. The principle objectives of this study are to evaluate the cost and technical differences between the liquid and solid propellant booster systems and to assess the development and operational cost savings available with a smaller orbiter.
Groundwater quality in the Coastal Los Angeles Basin, California
Fram, Miranda S.; Belitz, Kenneth
2012-01-01
The Coastal Los Angeles Basin study unit is approximately 860 square miles and consists of the Santa Monica, Hollywood, West Coast, Central, and Orange County Coastal Plain groundwater basins (California Department of Water Resources, 2003). The basins are bounded in part by faults, including the Newport-Inglewood fault zone, and are filled with Holocene-, Pleistocene-, and Pliocene-age marine and alluvial sediments. The Central Basin and Orange County Coastal Plain are divided into a forebay zone on the northeast and a pressure zone in the center and southwest. The forebays consist of unconsolidated coarser sediment, and the pressure zones are characterized by lenses of coarser sediment divided into confined to semi-confined aquifers by lenses of finer sediments. The primary aquifer system in the study unit is defined as those parts of the aquifer system corresponding to the perforated intervals of wells listed in the California Department of Public Health (CDPH) database of public-supply wells. The majority of public-supply wells are drilled to depths of 510 to 1,145 feet, consist of solid casing from the land surface to a depth of about 300 to 510 feet, and are perforated below the solid casing. Water quality in the primary aquifer system may differ from that in the shallower and deeper parts of the aquifer systems.
Pretest analysis document for Test S-NH-1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Owca, W.A.
This report documents the pretest analysis calculation completed with the RELAP5/MOD2/CY3601 code for Semiscale MOD-2C Test S-NH-1. The test will simulate the shear of a small diameter penetration of a cold leg, equivalent to 0.5% of the cold leg flow area. The high pressure injection system is assumed to be inoperative throughout the transient. The recovery procedure consists of latching open both steam generator ADV's while feeding with auxiliary feedwater, and accumulator operation. Recovery will be initiated upon a peak cladding temperature of 811 K (1000/sup 0/F). The test will be terminated when primary pressure has been reduced to themore » low pressure injection system setpoint of 1.38 MPa (200 psia). The calculated results indicate that the test objectives can be achieved and the proposed test scenario poses no threat to personnel or to plant integrity. 12 figs.« less
Analysis of pressure spectra measurements in a ducted combustion system. Ph.D. Thesis - Toledo Univ.
NASA Technical Reports Server (NTRS)
Miles, J. H.
1980-01-01
Combustion noise propagation in an operating ducted liquid fuel combustion system is studied in relation to the development of combustion noise prediction and suppression techniques. The presence of combustor emissions in the duct is proposed as the primary mechanism producing the attenuation and dispersion of combustion noise propagating in an operating liquid fuel combustion system. First, a complex mathematical model for calculating attenuation and dispersion taking into account mass transfer, heat transfer, and viscosity effects due to the presence of liquid fuel droplets or solid soot particles is discussed. Next, a simpler single parameter model for calculating pressure auto-spectra and cross-spectra which takes into account dispersion and attenuation due to heat transfer between solid soot particles and air is developed. Then, auto-spectra and cross-spectra obtained from internal pressure measurements in a combustion system consisting of a J-47 combustor can, a spool piece, and a long duct are presented. Last, analytical results obtained with the single parameter model are compared with the experimental measurements. The single parameter model results are shown to be in excellent agreement with the measurements.
Analysis of pressure spectra measurements in a ducted combustion system
NASA Astrophysics Data System (ADS)
Miles, J. H.
1980-11-01
Combustion noise propagation in an operating ducted liquid fuel combustion system is studied in relation to the development of combustion noise prediction and suppression techniques. The presence of combustor emissions in the duct is proposed as the primary mechanism producing the attenuation and dispersion of combustion noise propagating in an operating liquid fuel combustion system. First, a complex mathematical model for calculating attenuation and dispersion taking into account mass transfer, heat transfer, and viscosity effects due to the presence of liquid fuel droplets or solid soot particles is discussed. Next, a simpler single parameter model for calculating pressure auto-spectra and cross-spectra which takes into account dispersion and attenuation due to heat transfer between solid soot particles and air is developed. Then, auto-spectra and cross-spectra obtained from internal pressure measurements in a combustion system consisting of a J-47 combustor can, a spool piece, and a long duct are presented. Last, analytical results obtained with the single parameter model are compared with the experimental measurements. The single parameter model results are shown to be in excellent agreement with the measurements.
2013-01-01
Background Racial disparities in blood pressure control have been well documented in the United States. Research suggests that many factors contribute to this disparity, including barriers to care at patient, clinician, healthcare system, and community levels. To date, few interventions aimed at reducing hypertension disparities have addressed factors at all of these levels. This paper describes the design of Project ReD CHiP (Reducing Disparities and Controlling Hypertension in Primary Care), a multi-level system quality improvement project. By intervening on multiple levels, this project aims to reduce disparities in blood pressure control and improve guideline concordant hypertension care. Methods Using a pragmatic trial design, we are implementing three complementary multi-level interventions designed to improve blood pressure measurement, provide patient care management services and offer expanded provider education resources in six primary care clinics in Baltimore, Maryland. We are staggering the introduction of the interventions and will use Statistical Process Control (SPC) charting to determine if there are changes in outcomes at each clinic after implementation of each intervention. The main hypothesis is that each intervention will have an additive effect on improvements in guideline concordant care and reductions in hypertension disparities, but the combination of all three interventions will result in the greatest impact, followed by blood pressure measurement with care management support, blood pressure measurement with provider education, and blood pressure measurement only. This study also examines how organizational functioning and cultural competence affect the success of the interventions. Discussion As a quality improvement project, Project ReD CHiP employs a novel study design that specifically targets multi-level factors known to contribute to hypertension disparities. To facilitate its implementation and improve its sustainability, we have incorporated stakeholder input and tailored components of the interventions to meet the specific needs of the involved clinics and communities. Results from this study will provide knowledge about how integrated multi-level interventions can improve hypertension care and reduce disparities. Trial Registration ClinicalTrials.gov NCT01566864 PMID:23734703
Optimization of stent implantation using a high pressure inflation protocol.
Vallurupalli, Srikanth; Bahia, Amit; Ruiz-Rodriguez, Ernesto; Ahmed, Zubair; Hakeem, Abdul; Uretsky, Barry F
2016-01-01
High-pressure inflation is the universal standard for stent deployment but a specific protocol for its use is lacking. We developed a standardized "pressure optimization protocol" (POP) using time to inflation pressure stability as an endpoint for determining the required duration of stent inflation. The primary study purpose was to determine the stent inflation time (IT) in a large patient cohort using the standardized inflation protocol, to correlate various patient and lesion characteristics with IT, and ascertain in an in vitro study the time for pressure accommodation within an inflation system. Six hundred fifteen stent implants in 435 patients were studied. Multivariate analysis was performed to determine predictors of longer ITs. In an in vitro study, various stents and balloons were inflated in air to determine the pressure accommodation time of the inflation system. The mean stent IT was 104 ± 41 sec (range 30-380 sec). Stent length was the only predictor of prolonged stent inflation. The "accommodation time" in vitro of the stent inflation system itself was 33 ± 24 sec. The protocol was safe requiring premature inflation termination in <3% of stent implants. No serious adverse events occurred. Achieving stable inflation pressure requires on average over 100 sec and may require several minutes in individual cases. Stent length increases IT. These results suggest that the widespread practice of rapid inflation/deflation may not be sufficient to fully expand the stent and that the use of a pressure stability protocol will allow for safe, predictable, and more complete stent deployment. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
Turboexpanders with pressurized magnetic bearings for off-shore applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Agahi, R.R.; Ershaghi, B.; Baudelocque, L.
1995-12-31
There are two primary parameters that encourage the use of magnetic bearings in turbomachinery: oil-free process and space requirements. For cryogenic processes such as hydrogen purification and ethylene plants, oil free process is the primary objective. In the case of off-shore platforms for oil and gas production, the occupied space and weight are of prime concern. In off-shore operations, the process gas density is usually higher than in normal process plants because the gas is untreated and at high pressure. High density process gas generates more windage loss and may also cause excessive radial load to journal bearings. The bearingmore » assembly design should be suitable for sour gas environments as well. Furthermore, the thrust bearing system should withstand process fluctuations which are more severe due to high pressure. In this paper, the authors explain their experience of designing a turboexpander-compressor with magnetic bearings for an off-shore oil production platform. They will present side load analysis and their solutions for heat dissipation and coping with process fluctuations.« less
Membrane Separation Processes at Low Temperatures
NASA Technical Reports Server (NTRS)
Parrish, Clyde
2002-01-01
The primary focus of Kennedy Space Center's gas separation activities has been for carbon dioxide, nitrogen, and argon used in oxygen production technologies for Martian in-situ resource utilization (ISRU) projects. Recently, these studies were expanded to include oxygen for regenerative life support systems. Since commercial membrane systems have been developed for separation of carbon dioxide, nitrogen, and oxygen, initially the studies focused on these membrane systems, but at lower operating temperatures and pressures. Current investigations art examining immobilized liquids and solid sorbents that have the potential for higher selectivity and lower operating temperatures. The gas separation studies reported here use hollow fiber membranes to separate carbon dioxide, nitrogen, and argon in the temperature range from 230 to 300 K. Four commercial membrane materials were used to obtain data at low feed and permeate pressures. These data were used with a commercial solution-diffusion modeling tool to design a system to prepare a buffer gas from the byproduct of a process to capture Martian carbon dioxide. The system was designed to operate, at 230 K with a production rate 0.1 sLpm; Feed composition 30% CO2, 44% N2, and 26% Ar; Feed pressure 104 kPa (780); and Permeate pressure 1 kPa (6 torr); Product concentration 600 ppm CO2. This new system was compared with a similar system designed to operate at ambient temperatures (298 K). The systems described above, along with data, test apparatus, and models are presented.
USDA-ARS?s Scientific Manuscript database
The reliance on fishmeal as a primary protein source is among the chief economic and environmental concerns in aquaculture today. Fishmeal-based feeds often require harvest from wild fish stocks, placing pressure on natural ecosystems and promoting price instability. Advances in alternative diet for...
14 CFR Appendix C to Part 135 - Helicopter Flight Recorder Specifications
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Helicopter Flight Recorder Specifications C.... C Appendix C to Part 135—Helicopter Flight Recorder Specifications Parameters Range Installed system... Maximum range +5% 1 1% 2 Engine torque Maximum range ±5% 1 1% 2 Flight Control—Hydraulic Pressure Primary...
Elementary School Leaders' Perceptions of Their Roles in Managing School Curriculum: A Case Study
ERIC Educational Resources Information Center
Shahadan, Azuraida; Oliver, Ron
2016-01-01
The implementation of the Malaysian National Education Blueprint in 2012 has expanded headmasters' responsibilities and roles in managing schools. The goal is to stabilize and strengthen the primary school education system, which brings tremendous pressure to bear on the headmasters charged with managing schools, especially in managing the school…
Drexler, Robert L.
1992-01-01
A rotary seal used to prevent the escape of contaminates from a rotating kiln incinerator. The rotating seal combines a rotating disc plate which is attached to the rotating kiln shell and four sets of non-rotating carbon seal bars housed in a primary and secondary housing and which rub on the sides of the disc. A seal air system is used to create a positive pressure in a chamber between the primary and secondary seals to create a positive air flow into the contaminated gas chamber. The seal air system also employs an air inlet located between the secondary and tertiary seals to further insure that no contaminates pass the seal and enter the external environment and to provide makeup air for the air which flows into the contaminated gas chamber. The pressure exerted by the seal bars on the rotating disc is controlled by means of a preload spring. The seal is capable of operating in a thermally changing environment where the both radial expansion and axial movement of the rotating kiln do not result in the failure of the seal.
Photon Intermediate Direct Energy Conversion Using a Strontium-90 Beta Source
NASA Astrophysics Data System (ADS)
Schott, Robert J.
This thesis covers an examination of a need for a compact, long lived power source and a proof of concept for one such design. To begin, tests were done dealing with photovoltaics and their lifetime while undergoing radiation damage from the source of interest, Strontium-90 (Sr-90). After completing these tests a system was designed, built, and ultimately tested over a range of pressures in order to test if a Photon Intermediate Direct Energy Conversion (PIDEC) system would be potentially viable. In brief, the PIDEC system tested for this thesis used two excimer gasses, Argon and Xenon, to produce photons. These gasses were excited into excimer production using a 10 mCi Sr-90 source and held in place at pressures ranging from 10-6 to 2400 psi by a pressure vessel. Photons produced were guided towards a photovoltaic by a mirror chamber lined with high efficiency aluminum mirrors. Outside of the pressure vessel a picoammeter read the current off of the photovoltaic and sent the current to a computer for data processing. Of primary interest was how the current changed based on the amount of energy captured by the gas plenum which was related to the pressure of the system. The overall efficiency of this system was low due to a non-optimized waveguide, much of the beta energy being lost beyond the gas plenum, and other factors. However, the results were sufficient to show that the process was successfully completed and making a new system to optimize for these features is warranted.
Hartle, A; McCormack, T; Carlisle, J; Anderson, S; Pichel, A; Beckett, N; Woodcock, T; Heagerty, A
2016-03-01
This guideline aims to ensure that patients admitted to hospital for elective surgery are known to have blood pressures below 160 mmHg systolic and 100 mmHg diastolic in primary care. The objective for primary care is to fulfil this criterion before referral to secondary care for elective surgery. The objective for secondary care is to avoid spurious hypertensive measurements. Secondary care should not attempt to diagnose hypertension in patients who are normotensive in primary care. Patients who present to pre-operative assessment clinics without documented primary care blood pressures should proceed to elective surgery if clinic blood pressures are below 180 mmHg systolic and 110 mmHg diastolic. © 2016 The Authors. Anaesthesia published by John Wiley & Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland.
Operational considerations in monitoring oxygen levels at the National Transonic Facility
NASA Technical Reports Server (NTRS)
Zalenski, M. A.; Rowe, E. L.; Mcphee, J. R.
1985-01-01
Laboratory monitoring of the level of oxygen in sample gas mixtures is a process which can be performed with accurate and repeatable results. Operations at the National Transonic Facility require the storage and pumping of large volumes of liquid nitrogen. To protect against the possibility of a fault resulting in a localized oxygen deficient atmosphere, the facility is equipped with a monitoring system with an array of sensors. During the early operational stages, the system produced recurrent alarms, none of which could be traced to a true oxygen deficiency. A thorough analysis of the system was undertaken with primary emphasis placed on the sensor units. These units sense the partial pressure of oxygen which, after signal conditioning, is presented as a % by volume indication at the system output. It was determined that many of the problems experienced were due to a lack of proper accounting for the partial pressure/% by volume relationship, with a secondary cause being premature sensor failure. Procedures were established to consider atmospherically induced partial pressure variations. Sensor rebuilding techniques were examined, and those elements contributing to premature sensor failure were identified. The system now operates with a high degree of confidence and reliability.
PRA (Probabilistic Risk Assessment) Applications Program for inspection at Oconee Unit 3
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gore, B.F.; Vo, T.V.; Harris, M.S.
1987-10-01
The extensive Oconee-3 PRA performed by EPRI has been analyzed to identify plant systems and components important to minimizing public risk, and to identify the primary failure modes of these components. This information has been tabulated, and correlated with inspection modules from the NRC Inspection and Enforcement Manual. The report presents a series of tables, organized by system and prioritized by public risk (in person-rem per year), which identify components associated with 98% of the inspectable risk due to plant operation. External events (earthquakes, tornadoes, fires and floods) are not addressed because inspections cannot directly minimize the risks from thesemore » events; however, flooding caused by the breach of internal systems is addressed. The systems addressed, in descending order of risk importance, are: Reactor Building Spray, R B Cooling, Condenser Circulating Water, Safety Relief Valves, Low Pressure Injection, Standby Shutdown Facility-High Pressure Injection, Low-Pressure Service Water, and Emergency Feedwater. This ranking is based on the Fussel-Vesely measure of risk importance, i.e., the fraction of the total risk which involves failures of the system of interest. 8 refs., 25 tabs.« less
Aortic Baroreceptors Display Higher Mechanosensitivity than Carotid Baroreceptors.
Lau, Eva On-Chai; Lo, Chun-Yin; Yao, Yifei; Mak, Arthur Fuk-Tat; Jiang, Liwen; Huang, Yu; Yao, Xiaoqiang
2016-01-01
Arterial baroreceptors are mechanical sensors that detect blood pressure changes. It has long been suggested that the two arterial baroreceptors, aortic and carotid baroreceptors, have different pressure sensitivities. However, there is no consensus as to which of the arterial baroreceptors are more sensitive to changes in blood pressure. In the present study, we employed independent methods to compare the pressure sensitivity of the two arterial baroreceptors. Firstly, pressure-activated action potential firing was measured by whole-cell current clamp with a high-speed pressure clamp system in primary cultured baroreceptor neurons. The results show that aortic depressor neurons possessed a higher percentage of mechano-sensitive neurons. Furthermore, aortic baroreceptor neurons show a lower pressure threshold than that of carotid baroreceptor neurons. Secondly, uniaxial stretching of baroreceptor neurons, that mimics the forces exerted on blood vessels, elicited a larger increase in intracellular Ca(2+) rise in aortic baroreceptor neurons than in carotid baroreceptor neurons. Thirdly, the pressure-induced action potential firing in the aortic depressor nerve recorded in vivo was also higher. The present study therefore provides for a basic physiological understanding on the pressure sensitivity of the two baroreceptor neurons and suggests that aortic baroreceptors have a higher pressure sensitivity than carotid baroreceptors.
Fuentes, Ramón; Engelke, Wilfried; Flores, Tania; Navarro, Pablo; Borie, Eduardo; Curiqueo, Aldo; Salamanca, Carlos
2015-01-01
Under normal conditions, the oral cavity presents a perfect system of equilibrium between teeth, soft tissues and tongue. The equilibrium of soft tissues forms a closed capsular matrix, generating differences with the atmospheric environment. This difference is known as intraoral pressure. Negative intraoral pressure is fundamental to the stabilization of the soft palate and tongue, reducing neuromuscular activity for the permeability of the respiratory tract. Thus, the aim of this study was to describe the variations of intraoral pressure of the sub-palatal space (SPS) under different physiological conditions and biofunctional phases. A case series was conducted with 20 individuals aged between 18 and 25. The intraoral pressures were measured through a system of cannulae connected to a digital pressure meter in the SPS during seven biofunctional phases. Descriptive statistics were used based on the mean and standard deviation. The data recorded pressure variations under physiological conditions, reaching 65 mbar as the intraoral peak in forced inspiration. In the swallowing phase, peaks reached -91.9 mbar. No pressure variations were recorded in terms of atmospheric changes with the mouth open and semi-open. The data obtained during the swallowing and forced inspiration phases indicated forced lingual activity. In the swallowing phase, the adequate position of the tongue creates negative intraoral pressure, which represents a fundamental mechanism for the physical stabilization of the soft palate. This information could contribute to subsequent research into the treatment of primary roncopathies.
Lasting Retinal Injury in a Mouse Model of Blast-Induced Trauma.
Mammadova, Najiba; Ghaisas, Shivani; Zenitsky, Gary; Sakaguchi, Donald S; Kanthasamy, Anumantha G; Greenlee, Justin J; West Greenlee, M Heather
2017-07-01
Traumatic brain injury due to blast exposure is currently the most prevalent of war injuries. Although secondary ocular blast injuries due to flying debris are more common, primary ocular blast exposure resulting from blast wave pressure has been reported among survivors of explosions, but with limited understanding of the resulting retinal pathologies. Using a compressed air-driven shock tube system, adult male and female C57BL/6 mice were exposed to blast wave pressure of 300 kPa (43.5 psi) per day for 3 successive days, and euthanized 30 days after injury. We assessed retinal tissues using immunofluorescence for glial fibrillary acidic protein, microglia-specific proteins Iba1 and CD68, and phosphorylated tau (AT-270 pThr181 and AT-180 pThr231). Primary blast wave pressure resulted in activation of Müller glia, loss of photoreceptor cells, and an increase in phosphorylated tau in retinal neurons and glia. We found that 300-kPa blasts yielded no detectable cognitive or motor deficits, and no neurochemical or biochemical evidence of injury in the striatum or prefrontal cortex, respectively. These changes were detected 30 days after blast exposure, suggesting the possibility of long-lasting retinal injury and neuronal inflammation after primary blast exposure. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.
Ten year environmental test of glass fiber/epoxy pressure vessels
NASA Technical Reports Server (NTRS)
Faddoul, J. R.
1985-01-01
By the beginning of the 1970's composite pressure vessels had received a significant amount of development effort, and applications were beginning to be investigated. One of the first applications grew out of NASA Johnson Space Center efforts to develop a superior emergency breathing system for firemen. While the new breathing system provided improved wearer comfort and an improved mask and regulator, the primary feature was low weight which was achieved by using a glass fiber reinforced aluminum pressure vessel. Part of the development effort was to evaluate the long term performance of the pressure vessel and as a consequence, some 30 bottles for a test program were procured. These bottles were then provided to NASA Lewis Research Center where they were maintained in an outdoor environment in a pressurized condition for a period of up to 10 yr. During this period, bottles were periodically subjected to cyclic and burst testing. There was no protective coating applied to the fiberglass/epoxy composite, and significant loss in strength did occur as a result of the environment. Similar bottles stored indoors showed little, if any, degradation. This report contains a description of the pressure vessels, a discussion of the test program, data for each bottle, and appropriate plots, comparisons, and conclusions.
Method and system for low-NO.sub.x dual-fuel combustion of liquid and/or gaseous fuels
Gard, Vincent; Chojnacki, Dennis A; Rabovitser, Ioseph K
2014-12-02
A method and apparatus for combustion in which a pressurized preheated liquid fuel is atomized and a portion thereof flash vaporized, creating a mixture of fuel vapor and liquid droplets. The mixture is mixed with primary combustion oxidant, producing a fuel/primary oxidant mixture which is then injected into a primary combustion chamber in which the fuel/primary oxidant mixture is partially combusted, producing a secondary gaseous fuel containing hydrogen and carbon oxides. The secondary gaseous fuel is mixed with a secondary combustion oxidant and injected into the second combustion chamber wherein complete combustion of the secondary gaseous fuel is carried out. The resulting second stage flue gas containing very low amounts of NO.sub.x is then vented from the second combustion chamber.
Hypertension management in rural primary care facilities in Zambia: a mixed methods study.
Yan, Lily D; Chirwa, Cindy; Chi, Benjamin H; Bosomprah, Samuel; Sindano, Ntazana; Mwanza, Moses; Musatwe, Dennis; Mulenga, Mary; Chilengi, Roma
2017-02-03
Improved primary health care is needed in developing countries to effectively manage the growing burden of hypertension. Our objective was to evaluate hypertension management in Zambian rural primary care clinics using process and outcome indicators to assess the screening, monitoring, treatment and control of high blood pressure. Better Health Outcomes through Mentoring and Assessment (BHOMA) is a 5-year, randomized stepped-wedge trial of improved clinical service delivery underway in 46 rural Zambian clinics. Clinical data were collected as part of routine patient care from an electronic medical record system, and reviewed for site performance over time according to hypertension related indicators: screening (blood pressure measurement), management (recorded diagnosis, physical exam or urinalysis), treatment (on medication), and control. Quantitative data was used to develop guides for qualitative in-depth interviews, conducted with health care providers at a proportional sample of half (20) of clinics. Qualitative data was iteratively analyzed for thematic content. From January 2011 to December 2014, 318,380 visits to 46 primary care clinics by adults aged ≥ 25 years with blood pressure measurements were included. Blood pressure measurement at vital sign screening was initially high at 89.1% overall (range: 70.1-100%), but decreased to 62.1% (range: 0-100%) by 48 months after intervention start. The majority of hypertensive patients made only one visit to the clinics (57.8%). Out of 9022 patients with at least two visits with an elevated blood pressure, only 49.3% had a chart recorded hypertension diagnosis. Process indicators for monitoring hypertension were <10% and did not improve with time. In in-depth interviews, antihypertensive medication shortages were common, with 15/20 clinics reporting hydrochlorothiazide-amiloride stockouts. Principal challenges in hypertension management included 1) equipment and personnel shortages, 2) provider belief that multiple visits were needed before official management, 3) medication stock-outs, leading to improper prescriptions and 4) poor patient visit attendance. Our findings suggest that numerous barriers stand in the way of hypertension diagnosis and management in Zambian primary health facilities. Future work should focus on performance indicator development and validation in low resource contexts, to facilitate regular and systematic data review to improve patient outcomes. ClinicalTrials.gov, Identifier NCT01942278 . Date of Registration: September 2013.
Shukor, Ali R; Klazinga, Niek S; Kringos, Dionne S
2017-08-23
This study presents a descriptive synthesis of Kurdistan Region of Iraq's (KRI) primary care system, which is undergoing comprehensive primary care reforms within the context of a cross-cutting structural economic adjustment program and protracted security, humanitarian, economic and political crises. The descriptive analysis used a framework operationalizing Starfield's classic primary care model for health services research. A scoping review was performed using relevant sources, and expert consultations were conducted for completing and validating data. The descriptive analysis presents a complex narrative of a primary care system undergoing classical developmental processes of transitioning middle-income countries. The system is simultaneously under tremendous pressure to adapt to the continuously changing, complex and resource-intensive needs of sub-populations exhibiting varying morbidity patterns, within the context of protracted security, humanitarian, economic, and political crises. Despite exhibiting significant resilience in the face of the ongoing crises, the continued influx of IDPs and Syrian refugees, coupled with extremely limited resources and weak governance at policy, organizational and clinical levels threaten the sustainability of KRI's public primary care system. Diverse trajectories to the strengthening and development of primary care are underway by local and international actors, notably the World Bank, RAND Corporation, UN organizations and USAID, focusing on varying imperatives related to the protracted humanitarian and economic crises. The convergence, interaction and outcomes of the diverse initiatives and policy approaches in relation to the development of KRI's primary care system are complex and highly uncertain. A common vision of primary care is required to align resources, initiatives and policies, and to enable synergy between all local and international actors involved in the developmental and humanitarian response. Further research that integrates the knowledge synthesized in this article, and enables actors in KRI to learn from their own experiences and efforts, along with those of other jurisdictions, would be invaluable towards the ongoing development of primary care.
Elasto-optics in double-coated optical fibers induced by axial strain and hydrostatic pressure.
Yang, Yu-Ching; Lee, Haw-Long; Chou, Huann-Ming
2002-04-01
Stresses, microbending loss, and refractive-index changes induced simultaneously by axial strain and hydrostatic pressure in double-coated optical fibers are analyzed. The lateral pressure and normal stresses in the optical fiber, primary coating, and secondary coating are derived. Also presented are the microbending loss and refractive-index changes in the glass fiber. The normal stresses are affected by axial strain, hydrostatic pressure, material properties, and thickness of the primary and secondary coatings. It is found that microbending loss decreases with increasing thickness, the Young's modulus, and the Poisson's ratio of the secondary coating but increases with the increasing Young's modulus and Poisson's ratio of the primary coating. Similarly, changes in refractive index in the glass fiber decrease with the increasing Young's modulus and Poisson's ratio of the secondary coating but increase with the increasing Young's modulus and Poisson's ratio of the primary coating. Therefore, to minimize microbending loss induced simultaneously by axial strain and hydrostatic pressure in the glass fiber, the polymeric coatings should be suitably selected. An optimal design procedure is also indicated.
JEM Experiment Logistics Module Pressurized Section
2007-04-02
In the Space Station Processing Facility, the JEM Experiment Logistics Module Pressurized Section is lowered onto a scale for weight and center-of-gravity measurements. The module will then be moved to a work stand. The logistics module is one of the components of the Japanese Experiment Module or JEM, also known as Kibo, which means "hope" in Japanese. Kibo comprises six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007.
Unsteady surface pressure measurements on a slender delta wing undergoing limit cycle wing rock
NASA Technical Reports Server (NTRS)
Arena, Andrew S., Jr.; Nelson, Robert C.
1991-01-01
An experimental investigation of slender wing limit cycle motion known as wing rock was investigated using two unique experimental systems. Dynamic roll moment measurements and visualization data on the leading edge vortices were obtained using a free to roll apparatus that incorporates an airbearing spindle. In addition, both static and unsteady surface pressure data was measured on the top and bottom surfaces of the model. To obtain the unsteady surface pressure data a new computer controller drive system was developed to accurately reproduce the free to roll time history motions. The data from these experiments include, roll angle time histories, vortex trajectory data on the position of the vortices relative to the model's surface, and surface pressure measurements as a function of roll angle when the model is stationary or undergoing a wing rock motion. The roll time history data was numerically differentiated to determine the dynamic roll moment coefficient. An analysis of these data revealed that the primary mechanism for the limit cycle behavior was a time lag in the position of the vortices normal to the wing surface.
Dynamic mass exchange in doubly degenerate binaries. I - 0.9 and 1.2 solar mass stars
NASA Technical Reports Server (NTRS)
Benz, W.; Cameron, A. G. W.; Press, W. H.; Bowers, R. L.
1990-01-01
The dynamic mass exchange process in doubly degenerate binaries was investigated using a three-dimensional numerical simulation of the evolution of a doubly degenerate binary system in which the primary is a 1.2-solar-mass white dwarf and the Roche lobe filling secondary is a 0.9-solar-mass dwarf. The results show that, in a little more than two orbital periods, the secondary is completely destroyed and transformed into a thick disk orbiting about the primary. Since only a very small fraction of the mass (0.0063 solar mass) escapes the system, the evolution of the binary results in the formation of a massive object. This object is composed of three parts, the initial white dwarf primary, a very hot pressure-supported spherical envelope, and a rotationally supported outer disk. The evolution of the system can be understood in terms of a simple analytical model where it is shown that the angular momentum carried by the mass during the transfer and stored in the disk determines the evolution of the system.
[Catastrophic antiphospholipid syndrome in the immediate puerperium].
Ortiz, P; Castro, A; Vallés, M; Coll, E; Casas, M; Mauri, J M
2003-01-01
We describe a female previously diagnosed of primary antiphospholipid antibody syndrome who presented a preclampsia in the second pregnancy. An urgent caesaria was made because of a worsening high blood pressure and oliguria. In the immediated puerperium she showed low platelets and persistent high blood pressure. Afterwards acute renal failure and neurological signs with a severe aortic valvulopathy were diagnosed. An haemolytic anemia was also detected. Definitive diagnosis was made by kidney biopsy with the result of a thrombotic microangiopathy. Treatment with low weight heparin and aspirin and systemic corticosteroids was started in the immediate puerperium and fresh frozen plasma was then added with a good response to treatment. Actually she is still with high blood pressure, aortic valvulopathy. Renal function is normal one year later.
Cryogenic reactant storage for lunar base regenerative fuel cells
NASA Technical Reports Server (NTRS)
Kohout, Lisa L.
1989-01-01
There are major advantages to be gained by integrating a cryogenic reactant storage system with a hydrogen-oxygen regenerative fuel cell (RFC) to provide on-site electrical power during the lunar night. Although applicable to any power system using hydrogen-oxygen RFC's for energy storage, cryogenic reactant storage offers a significant benefit whenever the sun/shade cycle and energy storage period approach hundreds of hours. For solar power installations on the moon, cryogenic reactant storage reduces overall specific mass and meteoroid vulnerability of the system. In addition, it offers synergistic benefits to on-site users, such as availability of primary fuel cell reactants for surface rover vehicles and cryogenic propellants for OTV's. The integration involves processing and storing the RFC reactant streams as cryogenic liquids rather than pressurized gases, so that reactant containment (tankage per unit mass of reactants) can be greatly reduced. Hydrogen-oxygen alkaline RFC's, GaAs photovoltaic (PV) arrays, and space cryogenic processing/refrigeration technologies are assumed to be available for the conceptual system design. Advantages are demonstrated by comparing the characteristics of two power system concepts: a conventional lunar surface PV/RFC power system using pressurized gas storage in SOA filament wound pressure vessels and, that same system with gas liquefaction and storage replacing the pressurized storage. Comparisons are made at 20 and 250 kWe. Although cryogenic storage adds a processing plant (drying and liquefaction) to the system plus 30 percent more solar array to provide processing power, the approximate order of magnitude reduction in tankage mass, confirmed by this analysis, results in a reduction in overall total system mass of approximately 50 percent.
Flow of GE90 Turbofan Engine Simulated
NASA Technical Reports Server (NTRS)
Veres, Joseph P.
1999-01-01
The objective of this task was to create and validate a three-dimensional model of the GE90 turbofan engine (General Electric) using the APNASA (average passage) flow code. This was a joint effort between GE Aircraft Engines and the NASA Lewis Research Center. The goal was to perform an aerodynamic analysis of the engine primary flow path, in under 24 hours of CPU time, on a parallel distributed workstation system. Enhancements were made to the APNASA Navier-Stokes code to make it faster and more robust and to allow for the analysis of more arbitrary geometry. The resulting simulation exploited the use of parallel computations by using two levels of parallelism, with extremely high efficiency.The primary flow path of the GE90 turbofan consists of a nacelle and inlet, 49 blade rows of turbomachinery, and an exhaust nozzle. Secondary flows entering and exiting the primary flow path-such as bleed, purge, and cooling flows-were modeled macroscopically as source terms to accurately simulate the engine. The information on these source terms came from detailed descriptions of the cooling flow and from thermodynamic cycle system simulations. These provided boundary condition data to the three-dimensional analysis. A simplified combustor was used to feed boundary conditions to the turbomachinery. Flow simulations of the fan, high-pressure compressor, and high- and low-pressure turbines were completed with the APNASA code.
Aggarwal, Rahul; Mirzan, Haares; Chiu, Nicholas; Steinkamp, Jackson
2018-02-26
ACCORD and SPRINT are the best randomized controlled trial data evaluating the effects of blood pressure targets below 140 mmHg. These trials had contradictory results regarding the benefits of intensive antihypertensive therapy. We investigate if this discordance was driven by SPRINT's inclusion of Heart Failure in its primary outcome, as this is a parameter not included in ACCORD's original primary outcome. This analysis helps to resolve a significant area of contention. Individual patient data from 4733 participants in ACCORD were analyzed from time of randomization. All participants were diabetic and at increased cardiovascular risk. Participants were assigned to their original intervention, a standard blood pressure target of less than 140 mmHg or an intensive target of less than 120 mmHg. Primary composite outcome was defined as in SPRINT: a composite of first occurrence of myocardial infarction, stroke, heart failure, death from cardiovascular causes, and other acute coronary syndromes. Primary outcome was not significantly different between standard and intensive groups [HR: 0.89; 95% CI: (0.76-1.03); p = 0.108]. The primary composite outcome occurred in 370 participants in the standard group (15.6%) and 324 participants in the intensive group (13.7%), with an event rate of 3.38% per year for the standard group and 3.01% per year for the intensive group. Differing results between ACCORD and SPRINT are not attributable to ACCORD's exclusion of Heart Failure from its original primary outcome measurement. No significant differences in primary outcome were observed between intensive and standard blood pressure groups in the ACCORD patients under the SPRINT primary outcome definition. Caution should be taken in extrapolating the intensive blood pressure control benefits of SPRINT to the diabetic population.
Applying organizational behavior theory to primary care.
Mullangi, Samyukta; Saint, Sanjay
2017-03-01
Addressing the mounting primary care shortage in the United States has been a focus of educators and policy makers, especially with the passage of the Affordable Care Act in 2010 and the Medicare Access and CHIP Reauthorization Act in 2015, placing increased pressure on the system. The Association of American Medical Colleges recently projected a shortage of as many as 65,000 primary care physicians by 2025, in part because fewer than 20% of medical students are picking primary care for a career. We examined the issue of attracting medical students to primary care through the lens of organizational behavior theory. Assuming there are reasons other than lower income potential for why students are inclined against primary care, we applied various principles of the Herzberg 2-factor theory to reimagine the operational flow and design of primary care. We conclude by proposing several solutions to enrich the job, such as decreasing documentation requirements, reducing the emphasis on specialty consultations, and elevating physicians to a supervisory role.
Management of cardiovascular risk in systemic lupus erythematosus: a systematic review.
Andrades, C; Fuego, C; Manrique-Arija, S; Fernández-Nebro, A
2017-11-01
Systemic lupus erythematosus is associated with accelerated atherosclerosis and increased risk of cardiovascular complications. The aim of this study was to review the effectiveness of interventions for primary and secondary prevention of cardiovascular events and mortality and to review the effectiveness of interventions for cardiovascular risk factor reduction in systemic lupus erythematosus patients. A systematic review was conducted. Electronic databases Medline and Embase (1961-2015) were searched. Nineteen articles met the inclusion criteria and were selected. Low-calorie and/or low glycaemic index calories may be a useful option for secondary prevention in obese patients with systemic lupus erythematosus, and exercise would be useful in improving the endothelial function measured by flow-mediated dilation in this group of patients. The use of lipid-lowering drugs may improve the lipid profile in patients with systemic lupus erythematosus and hyperlipidaemia, but the effect of this treatment on overall cardiovascular mortality remains unknown. Antiplatelets, anticoagulants, antimalarials and lipid-lowering drugs may be effective in the primary and secondary prevention of major cardiovascular events, such as acute myocardial infarction or stroke. Similarly, lipid-lowering drugs and antimalarial drugs appear to reduce the serum levels of total cholesterol, low-density lipoprotein, glucose, diastolic blood pressure and calcium deposition at the coronary arteries. They may also improve insulin resistance and the level of high-density lipoproteins. It appears that treatment with antihypertensive drugs reduces blood pressure in patients with systemic lupus erythematosus, but the available studies are of low quality.
Mountainous Coasts: A change to the GFS post codes will remove a persistent, spurious high pressure system ENVIRONMENTAL PREDICTION /NCEP/ WILL UPGRADE THE GFS POST PROCESSOR. THE PRIMARY EFFORT BEHIND THIS UPGRADE WILL BE TO UNIFY THE POST PROCESSING CODE FOR THE NORTH AMERICAN MESO SCALE /NAM/ MODEL AND THE GFS INTO
The Restructuring of Southern Agriculture: Data Needs for Economic and Policy Research.
ERIC Educational Resources Information Center
Skees, Jerry R.; Reed, Michael R.
The changing structure of Southern farming amid the pressures of the farm crisis produces an information gap that has forced policymakers to rely on trial and error in institutional design. Existing data systems monitoring the farm sector either use the county as the primary observation unit, or they survey different individual farmers each year.…
40 CFR Table 1b to Subpart Dddd of... - Add-on Control Systems Compliance Options
Code of Federal Regulations, 2010 CFR
2010-07-01
... Options For each of the following process units . . . You must comply with one of the following six...); pressurized refiners; primary tube dryers; secondary tube dryers; reconstituted wood product board coolers (at... are greater than or equal to 10 ppmvd. a You may choose to subtract methane from THC as carbon...
Improving organisational systems for diabetes care in Australian Indigenous communities.
Bailie, Ross; Si, Damin; Dowden, Michelle; O'Donoghue, Lynette; Connors, Christine; Robinson, Gary; Cunningham, Joan; Weeramanthri, Tarun
2007-05-06
Indigenous Australians experience disproportionately high prevalence of, and morbidity and mortality from diabetes. There is an urgent need to understand how Indigenous primary care systems are organised to deliver diabetes services to those most in need, to monitor the quality of diabetes care received by Indigenous people, and to improve systems for better diabetes care. The intervention featured two annual cycles of assessment, feedback workshops, action planning, and implementation of system changes in 12 Indigenous community health centres. Assessment included a structured review of health service systems and audit of clinical records. Main process of care measures included adherence to guideline-scheduled services and medication adjustment. Main patient outcome measures were HbA1c, blood pressure and total cholesterol levels. There was good engagement of health centre staff, with significant improvements in system development over the study period. Adherence to guideline-scheduled processes improved, including increases in 6 monthly testing of HbA1c from 41% to 74% (Risk ratio 1.93, 95% CI 1.71-2.10), 3 monthly checking of blood pressure from 63% to 76% (1.27, 1.13-1.37), annual testing of total cholesterol from 56% to 74% (1.36, 1.20-1.49), biennial eye checking by a ophthalmologist from 34% to 54% (1.68, 1.39-1.95), and 3 monthly feet checking from 20% to 58% (3.01, 2.52-3.47). Medication adjustment rates following identification of elevated HbA1c and blood pressure were low, increasing from 10% to 24%, and from 13% to 21% respectively at year 1 audit. However, improvements in medication adjustment were not maintained at the year 2 follow-up. Mean HbA1c value improved from 9.3 to 8.9% (mean difference -0.4%, 95% CI -0.7;-0.1), but there was no improvement in blood pressure or cholesterol control. This quality improvement (QI) intervention has proved to be highly acceptable in the Indigenous Australian primary care setting and has been associated with significant improvements in systems and processes of care and some intermediate outcomes. However, improvements appear to be limited by inadequate attention to abnormal clinical findings and medication management. Greater improvement in intermediate outcomes may be achieved by specifically addressing system barriers to therapy intensification through more effective engagement of medical staff in QI activities and/or greater use of nurse-practitioners.
Relationship of structure and function of the avian respiratory system to disease susceptibility.
Fedde, M R
1998-08-01
The avian respiratory system exchanges oxygen and carbon dioxide between the gas and the blood utilizing a relatively small, rigid, flow-through lung, and a system of air sacs that act as bellows to move the gas through the lung. Gas movement through the paleopulmonic parabronchi, the main gas exchanging bronchi, in the lung is in the same direction during both inspiration and expiration, i.e., from the mediodorsal secondary bronchi to the medioventral secondary bronchi. During inspiration, acceleration of the gas at the segmentum accelerans of the primary bronchus increases gas velocity so it does not enter the medioventral secondary bronchi. During expiration, airway resistance is increased in he intrapulmonary primary bronchus because of dynamic compression causing gas to enter the mediodorsal secondary bronchi. Reduction in air flow velocity may decrease the efficiency of this aerodynamic valving and thereby decrease the efficiency of gas exchange. The convective gas flow in the avian parabronchus is orientated at a 90 degree angle with respect to the parabronchial blood flow; hence, the cross-current designation of this gas exchanger. With this design, the partial pressure of oxygen in the blood leaving the parabronchus can be higher than that in the gas exiting this structure, giving the avian lung a high gas exchange efficacy. The relationship of the partial pressure of oxygen in the moist inspired gas to that in the blood leaving the lung is dependent on he rate of ventilation. A low ventilation rate may produce a ow oxygen partial pressure in part of the parabronchus, thereby inducing hypoxic vasoconstriction in the pulmonary arterioles supplying this region. Inhaled foreign particles are removed by nasal mucociliary action, by escalator in the trachea, primary bronchi, and secondary bronchi. Small particles that enter parabronchi appear to be phagocytized by the epithelial cells in eh atria and infundibulum. These particles can e transported to interstitial macrophages but the disposition of the particles from this site is unknown. The predominant site of respiratory infections in the caudal air sacs, compared to other parts of the respiratory system, can be explained by the gas flow pathway and the mechanisms present in the parabronchi for particle removal.
Girişgen, İlknur; Sönmez, Ferah; Yenisey, Ciğdem; Kurt-Omurlu, İmran
2014-01-01
Primary hypertension is the most important risk factor for chronic kidney disease in adulthood. However, the role of hypertension in kidney damage in childhood is not known exactly. The aim of this study was to evaluate the ambulatory blood pressure measurements of healthy children diagnosed as hypertensive with routine office blood pressure monitoring and to investigate the effects of primary hypertension on the kidney. Fifty-six patients who had blood pressure higher than 90th percentile during their well-child follow-up and 27 healthy children with normal blood pressure were included in the study. Twenty-four hour blood pressure measurements were recorded for all the patients. Microalbumin and N-acetyl-β-D-glucosaminidase (NAG) levels in the 24-hour urine were determined in the study groups. According to the results of ambulatory blood pressure measurements, 52% of the patients were diagnosed as white coat hypertension. The patients and the white coat hypertensive group had higher levels of urinary NAG than the control group. No significant difference was found in the levels of urinary microalbumin excretion between the primary hypertension and control groups. It was thought that ambulatory blood pressure measurement was necessary for the true diagnosis of hypertension in children, and further, that primary and white coat hypertension had effects on kidney damage in childhood. It is suggested that urine NAG excretion might be used as an early sign of hypertension-induced renal damage.
Phase equilibria study of pseudobrookite type minerals
NASA Technical Reports Server (NTRS)
Friel, J. J.
1974-01-01
Pseudobrookite, is found in volcanic rocks, and the mineral armalcolite ((Fe,Mg)Ti2O5) found in the Apollo 11 and subsequent lunar samples seems to be unique to the moon. In plutonic rocks on the earth, ilmenite and rutile were found with what appears to be an equilibrium liquidus texture, while on the moon armalcolite often appears to be the primary liquidus phase among Ti-oxides. This suggests that total pressure may be a factor in the formation of these minerals, and a knowledge of the phase relations in this system yields information about the pressure under which a given magma crystallized.
Chinese primary care physicians and work attitudes.
Shi, Leiyu; Hung, Li-Mei; Song, Kuimeng; Rane, Sarika; Tsai, Jenna; Sun, Xiaojie; Li, Hui; Meng, Qingyue
2013-01-01
China passed a landmark health care reform in 2009, aimed at improving health care for all citizens by strengthening the primary care system, largely through improvements to infrastructure. However, research has shown that the work attitudes of primary care physicians (PCPs) can greatly affect the stability of the overall workforce and the quality and delivery of health care. The purpose of this study is to investigate the relationship between reported work attitudes of PCPs and their personal, work, and educational characteristics. A multi-stage, complex sampling design was employed to select a sample of 434 PCPs practicing in urban and rural primary care settings, and a survey questionnaire was administered by researchers with sponsorship from the Ministry of Health. Four outcome measures describing work attitudes were used, as well as a number of personal-, work-, and practice-related factors. Findings showed that although most PCPs considered their work as important, a substantial number also reported large workloads, job pressure, and turnover intentions. Findings suggest that policymakers should focus on training and educational opportunities for PCPs and consider ways to ease workload pressures and improve salaries. These policy improvements must accompany reform efforts that are already underway before positive changes in reduced disparities and improved health outcomes can be realized in China.
Staff, Michael; Roberts, Christopher; March, Lyn
2016-10-01
To describe the completeness of routinely collected primary care data that could be used by computer models to predict clinical outcomes among patients with Type 2 Diabetes (T2D). Data on blood pressure, weight, total cholesterol, HDL-cholesterol and glycated haemoglobin levels for regular patients were electronically extracted from the medical record software of 12 primary care practices in Australia for the period 2000-2012. The data was analysed for temporal trends and for associations between patient characteristics and completeness. General practitioners were surveyed to identify barriers to recording data and strategies to improve its completeness. Over the study period data completeness improved up to around 80% complete although the recording of weight remained poorer at 55%. T2D patients with Ischaemic Heart Disease were more likely to have their blood pressure recorded (OR 1.6, p=0.02). Practitioners reported not experiencing any major barriers to using their computer medical record system but did agree with some suggested strategies to improve record completeness. The completeness of routinely collected data suitable for input into computerised predictive models is improving although other dimensions of data quality need to be addressed. Copyright © 2016 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.
Karlberg, B E; Kågedal, B; Tegler, L; Tolagen, K; Bergman, B
1976-03-31
Twenty-seven patients with hypertension were randomly allocated to a 10 month crossover study. Treatment consisted of spironolactone (200 mg/day for 2 months), propranolol (320 mg/day for 2 months) and combined administration of both drugs at half the dosage. Between treatment periods placebo was given for 2 months. Fourteen patients were previously untreated. The average pretreatment blood pressure for the entire group was 188/114 +/- 16/7(mean +/- standard deviation) mm Hg supine and 188/118 +/- 20/9 mm Hg standing. Both spironolactone and propranolol reduced blood pressure significantly in both the supine and standing positions. Upright plasma renin activity was determined by radioimmunoassay of angiotensin I. The average initial level was 1.9 +/- 1.2 (range 0.4 to 5.0) ng/ml/hr. There was a close correlation between plasma renin activity and the effects of the drugs: With increasing renin level the response to propranolol was better whereas the opposite was true for spironolactone. The combination of spironolactone and propranolol decreased the blood pressure still further in the supine and standing positions, irrespective of initial plasma renin activity. All patients achieved a normal supine pressure. Blood pressure and plasma renin activity returned toward pretreatment values during placebo administration. It is concluded that pretreatment levels of plasma renin activity can predict the antihypertensive response to propranolol and spironolactone. The combination of the two drugs, which have different modes of action, will effectively reduce blood pressure in hypertension. The results support the concept that the renin-angiotensin-aldo-sterone system may be involved in primary hypertension.
Wong, Holly; Kaufman, Jaime; Baylis, Barry; Conly, John M; Hogan, David B; Stelfox, Henry T; Southern, Danielle A; Ghali, William A; Ho, Chester H
2015-09-29
Interface pressure is a key risk factor in the development of pressure ulcers. Visual feedback of continuous interface pressure between the body and support surface could inform clinicians on repositioning strategies and play a key role in an overall strategy for the prevention and management of pressure ulcers. A parallel two-group randomized controlled clinical trial will be conducted to study the effect of continuous pressure imaging on reducing interface pressure and on the incidence of pressure ulcers in vulnerable hospital patients. A total of 678 eligible consenting inpatients at risk of pressure ulcer development in a tertiary acute care institution will be randomly allocated to either having the ForeSite PT™ system with the liquid-crystal display monitor turned on to provide visual feedback to the clinicians while also collecting continuous interface pressure data (intervention group) or to having the ForeSite PT™ system with monitor turned off (that is, not providing visual feedback) but still collecting continuous interface pressure data (control group), in a ratio of 1:1. Continuous interface pressure data will be collected in both groups for 3 days (72 h). Data collection will continue until discharge for a subset of approximately 60 patients. The primary outcome will be the differences in the two groups' interface pressure analysis. Interface pressure readings will be collected through hourly samplings of continuous interface pressure recordings. Secondary outcomes will be the differences between the two groups in pressure-related skin and soft tissue changes in areas at risk of pressure ulcer (obtained at baseline within 24 h of admission) and on the third day of the trial or at discharge and perceptions of the intervention by patients and clinicians (obtained on the third day or at discharge). This will be the first randomized controlled trial to investigate the effect of visual feedback with continuous interface pressure of vulnerable hospital patients across different care settings, and the association between interface pressure and development of pressure-related skin and soft tissue changes. The results could provide important information to guide clinical practice in the prevention and management of pressure ulcers. ClinicalTrials.gov NCT02325388 (date of registration: 24 December 2014).
Watret, L
1999-10-01
The Glasgow Acute Clinical Audit Sub-Committee on Pressure Sores has previously carried out studies of incidence of pressure ulcers in the medical directorates and case-mix-adjusted the figures for length of hospital stay and risk assessment score. Case-mix classification is 'classification of people or treatment placed into groups using characteristics associated with condition, treatment or outcome that can be used to predict need, resource, use of outcomes'. In this instance, crude pressure ulcer incidence figures may be adjusted for length of hospital stay and pressure sore risk assessment score, and stratified into groups, which allows like to be compared with like. The value in case-mix-adjusted figures lies in repeating the exercise, thus determining the trend for individual areas and assessing whether improvement in the quality of care is being achieved. This is more positive than creation of 'league tables' comparing simultaneous studies in a number of areas. The figures showed that there was no statistically significant difference between surgical directorates in trusts with regard to risk assessment scores and length of hospital stay. Gathering data on the incidence of pressure ulcer development allows us to identify where new sores are occurring, but does not critically analyse the nursing intervention taken in individual cases, which identifies preventive strategies. The Glasgow group's primary aim was to gather data on case-mix-adjusted incidence of pressure damage; the secondary objectives were to scrutinize the data to gather more general information on intrinsic and extrinsic factors which may predispose to pressure ulcer development. The study was carried out in the surgical directorate. Findings showed that incidence was low (1.1%), with the majority of sores being superficial. There was a correlation between pressure ulcer development and incontinence, evidence of under-utilization of moving and handling aids for prevention of pressure ulcers, and a need for greater collaboration between nursing staff and dietitians. All patients had access to pressure-reducing surfaces, with cut-foam pressure-reducing mattresses with vapour-permeable covers on all beds. Dynamic systems were available if the primary nurse identified a need for them.
Pressure ulcers: implementation of evidence-based nursing practice.
Clarke, Heather F; Bradley, Chris; Whytock, Sandra; Handfield, Shannon; van der Wal, Rena; Gundry, Sharon
2005-03-01
A 2-year project was carried out to evaluate the use of multi-component, computer-assisted strategies for implementing clinical practice guidelines. This paper describes the implementation of the project and lessons learned. The evaluation and outcomes of implementing clinical practice guidelines to prevent and treat pressure ulcers will be reported in a separate paper. The prevalence and incidence rates of pressure ulcers, coupled with the cost of treatment, constitute a substantial burden for our health care system. It is estimated that treating a pressure ulcer can increase nursing time up to 50%, and that treatment costs per ulcer can range from US$10,000 to $86,000, with median costs of $27,000. Although evidence-based guidelines for prevention and optimum treatment of pressure ulcers have been developed, there is little empirical evidence about the effectiveness of implementation strategies. The study was conducted across the continuum of care (primary, secondary and tertiary) in a Canadian urban Health Region involving seven health care organizations (acute, home and extended care). Trained surveyors (Registered Nurses) determined the prevalence and incidence of pressure ulcers among patients in these organizations. The use of a computerized decision-support system assisted staff to select optimal, evidence-based care strategies, record information and analyse individual and aggregate data. Evaluation indicated an increase in knowledge relating to pressure ulcer prevention, treatment strategies, resources required, and the role of the interdisciplinary team. Lack of visible senior nurse leadership; time required to acquire computer skills and to implement new guidelines; and difficulties with the computer system were identified as barriers. There is a need for a comprehensive, supported and sustained approach to implementation of evidence-based practice for pressure ulcer prevention and treatment, greater understanding of organization-specific barriers, and mechanisms for addressing the barriers.
The impact of circulation control on rotary aircraft controls systems
NASA Technical Reports Server (NTRS)
Kingloff, R. F.; Cooper, D. E.
1987-01-01
Application of circulation to rotary wing systems is a new development. Efforts to determine the near and far field flow patterns and to analytically predict those flow patterns have been underway for some years. Rotary wing applications present a new set of challenges in circulation control technology. Rotary wing sections must accommodate substantial Mach number, free stream dynamic pressure and section angle of attack variation at each flight condition within the design envelope. They must also be capable of short term circulation blowing modulation to produce control moments and vibration alleviation in addition to a lift augmentation function. Control system design must provide this primary control moment, vibration alleviation and lift augmentation function. To accomplish this, one must simultaneously control the compressed air source and its distribution. The control law algorithm must therefore address the compressor as the air source, the plenum as the air pressure storage and the pneumatic flow gates or valves that distribute and meter the stored pressure to the rotating blades. Also, mechanical collective blade pitch, rotor shaft angle of attack and engine power control must be maintained.
Pretest analysis document for Test S-NH-2
DOE Office of Scientific and Technical Information (OSTI.GOV)
Streit, J.E.; Owca, W.A.
This report documents the pretest analysis calculation completed with the RELAP5/MOD2/CY3601 code for Semiscale MOD-2C Test S-NH-2. The test will simulate the transient that results from the shear in a small diameter penetration of a cold leg, equivalent to 2.1% of the cold leg flow area. The high pressure injection system is assumed to be inoperative throughout the transient. The recovery procedure consists of latching open both steam generator atmospheric dump valves, supplying both steam generators with auxiliary feedwater system is assumed to be partially inoperative so the auxiliary feedwater flow is degraded. Recovery will be initiated upon a peakmore » cladding temperature of 811/sup 0/K (1000/sup 0/F). The test will be terminated when primary pressure has been reduced to the low pressure injection system setpoint of 1.38 MPa (200 psia). The calculated results indicate that the test objectives can be achieved and the proposed test scenario poses no threat to personnel or to plant integrity. 7 refs., 16 figs., 2 tabs.« less
Mahfud M. Zuhair; Yousif Ali Hussin; Michael Weir
2000-01-01
Mangrove forests are one of the primary features of coastal ecosystems throughout the tropical and subtropical regions of the world. Mangroves are very sensitive and fragile resources, and the pressures of increasing population, food production, and industrial and urban development have caused a significant proportion of the world's mangroves to be destroyed....
NASA Astrophysics Data System (ADS)
Narayan, A.; Singh, Nutan
2014-10-01
This paper studies the stability of Triangular Lagrangian points in the model of elliptical restricted three body problem, under the assumption that both the primaries are radiating. The model proposed is applicable to the well known binary systems Achird, Luyten, αCen AB, Kruger-60, Xi-Bootis. Conditional stability of the motion around the triangular points exists for 0≤ μ≤ μ ∗, where μ is the mass ratio. The method of averaging due to Grebenikov has been exploited throughout the analysis of stability of the system. The critical mass ratio depends on the combined effects of radiation of both the primaries and eccentricity of this orbit. It is found by adopting the simulation technique that the range of stability decreases as the radiation pressure parameter increases.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bacchiani, M.; Medich, C.; Rigamonti, M.
1995-09-01
The SPES-2 is a full height, full pressure experimental test facility reproducing the Westinghouse AP600 reactor with a scaling factor of 1/395. The experimental plant, designed and operated by SIET in Piacenza, consists of a full simulation of the AP600 primary core cooling system including all the passive and active safety systems. In 1992, Westinghouse, in cooperation with ENEL (Ente Nazionale per l` Energia Elettrica), ENEA (Enter per le numove Technlogie, l` Energia e l` Ambient), Siet (Societa Informazioni Esperienze Termoidraulich) and ANSALDO developed an experimental program to test the integrated behaviour of the AP600 passive safety systems. The SPES-2more » test matrix, concluded in November 1994, has examined the AP600 passive safety system response for a range of small break LOCAs at different locations on the primary system and on the passive system lines; single steam generator tube ruptures with passive and active safety systems and a main steam line break transient to demonstrate the boration capability of passive safety systems for rapid cooldown. Each of the tests has provided detailed experimental results for verification of the capability of the analysis methods to predict the integrated passive safety system behaviour. Cold and hot shakedown tests have been performed on the facility to check the characteristics of the plant before starting the experimental campaign. The paper first presents a description of the SPES-2 test facility then the main results of S01007 test {open_quotes}2{close_quotes} Cold Leg (CL) to Core Make-up Tank (CMT) pressure balance line break{close_quotes} are reported and compared with predictions performed using RELAP5/mod3/80 obtained by ANSALDO through agreement with U.S.N.R.C. (U.S. Nuclear Regulatory Commission). The SPES-2 nodalization and all the calculations here presented were performed by ANSALDO and sponsored by ENEL as a part of pre-test predictions for SPES-2.« less
The Nike Laser Facility and its Capabilities
NASA Astrophysics Data System (ADS)
Serlin, V.; Aglitskiy, Y.; Chan, L. Y.; Karasik, M.; Kehne, D. M.; Oh, J.; Obenschain, S. P.; Weaver, J. L.
2013-10-01
The Nike laser is a 56-beam krypton fluoride (KrF) system that provides 3 to 4 kJ of laser energy on target. The laser uses induced spatial incoherence to achieve highly uniform focal distributions. 44 beams are overlapped onto target with peak intensities up to 1016 W/cm2. The effective time-averaged illumination nonuniformity is < 0 . 2 %. Nike produces highly uniform ablation pressures on target allowing well-controlled experiments at pressures up to 20 Mbar. The other 12 laser beams are used to generate diagnostic x-rays radiographing the primary laser-illuminated target. The facility includes a front end that generates the desired temporal and spatial laser profiles, two electron-beam pumped KrF amplifiers, a computer-controlled optical system, and a vacuum target chamber for experiments. Nike is used to study the physics and technology issues of direct-drive laser fusion, such as, hydrodynamic and laser-plasma instabilities, studies of the response of materials to extreme pressures, and generation of X rays from laser-heated targets. Nike features a computer-controlled data acquisition system, high-speed, high-resolution x-ray and visible imaging systems, x-ray and visible spectrometers, and cryogenic target capability. Work supported by DOE/NNSA.
Levine, David Michael; Dixon, Ronald F; Linder, Jeffrey A
2018-04-23
Optimal management of hypertension requires frequent monitoring and follow-up. Novel, pragmatic interventions have the potential to engage patients, maintain blood pressure control, and enhance access to busy primary care practices. "Virtual visits" are structured asynchronous online interactions between a patient and a clinician to extend medical care beyond the initial office visit. To compare blood pressure control and healthcare utilization between patients who received virtual visits compared to usual hypertension care. Propensity score-matched, retrospective cohort study with adjustment by difference-in-differences. Primary care patients with hypertension. Patient participation in at least one virtual visit for hypertension. Usual care patients did not use a virtual visit but were seen in-person for hypertension. Adjusted difference in mean systolic blood pressure, primary care office visits, specialist office visits, emergency department visits, and inpatient admissions in the 180 days before and 180 days after the in-person visit. Of the 1051 virtual visit patients and 24,848 usual care patients, we propensity score-matched 893 patients from each group. Both groups were approximately 61 years old, 44% female, 85% White, had about five chronic conditions, and about 20% had a mean pre-visit systolic blood pressure of 140-160 mmHg. Compared to usual care, virtual visit patients had an adjusted 0.8 (95% CI, 0.3 to 1.2) fewer primary care office visits. There was no significant adjusted difference in systolic blood pressure control (0.6 mmHg [95% CI, - 2.0 to 3.1]), specialist visits (0.0 more visits [95% CI, - 0.3 to 0.3]), emergency department visits (0.0 more visits [95% CI, 0.0 to 0.01]), or inpatient admissions (0.0 more admissions [95% CI, 0.0 to 0.1]). Among patients with reasonably well-controlled hypertension, virtual visit participation was associated with equivalent blood pressure control and reduced in-office primary care utilization.
Mild hypothermia as a treatment for central nervous system injuries: Positive or negative effects
Darwazeh, Rami; Yan, Yi
2013-01-01
Besides local neuronal damage caused by the primary insult, central nervous system injuries may secondarily cause a progressive cascade of related events including brain edema, ischemia, oxida-tive stress, excitotoxicity, and dysregulation of calcium homeostasis. Hypothermia is a beneficial strategy in a variety of acute central nervous system injuries. Mild hypothermia can treat high intra-cranial pressure following traumatic brain injuries in adults. It is a new treatment that increases sur-vival and quality of life for patients suffering from ischemic insults such as cardiac arrest, stroke, and neurogenic fever following brain trauma. Therapeutic hypothermia decreases free radical produc-tion, inflammation, excitotoxicity and intracranial pressure, and improves cerebral metabolism after traumatic brain injury and cerebral ischemia, thus protecting against central nervous system dam-age. Although a series of pathological and physiological changes as well as potential side effects are observed during hypothermia treatment, it remains a potential therapeutic strategy for central nervous system injuries and deserves further study. PMID:25206579
Mild hypothermia as a treatment for central nervous system injuries: Positive or negative effects.
Darwazeh, Rami; Yan, Yi
2013-10-05
Besides local neuronal damage caused by the primary insult, central nervous system injuries may secondarily cause a progressive cascade of related events including brain edema, ischemia, oxida-tive stress, excitotoxicity, and dysregulation of calcium homeostasis. Hypothermia is a beneficial strategy in a variety of acute central nervous system injuries. Mild hypothermia can treat high intra-cranial pressure following traumatic brain injuries in adults. It is a new treatment that increases sur-vival and quality of life for patients suffering from ischemic insults such as cardiac arrest, stroke, and neurogenic fever following brain trauma. Therapeutic hypothermia decreases free radical produc-tion, inflammation, excitotoxicity and intracranial pressure, and improves cerebral metabolism after traumatic brain injury and cerebral ischemia, thus protecting against central nervous system dam-age. Although a series of pathological and physiological changes as well as potential side effects are observed during hypothermia treatment, it remains a potential therapeutic strategy for central nervous system injuries and deserves further study.
Use of communication tool within electronic medical record to improve primary nonadherence.
Kerner, Daniel E; Knezevich, Emily L
The primary objective of this study was to determine if an online reminder decreased the rate of primary nonadherence for antihypertensive medications in patients seen in 2 primary care clinics in Omaha, NE. The secondary objectives were to determine if patients receiving the intervention achieved lower blood pressure values at follow-up visits and to determine if the intervention decreased the number of days between prescribing and prescription pick-up. A report was generated in an electronic health record to identify patients prescribed a new antihypertensive medication from a physician at one of the primary care clinics. Patients that failed to pick up this new prescription from the pharmacy within 7 days were sent an electronic reminder via an online patient portal. A baseline comparator group was created with the use of retrospective chart reviews for the 6 months before prospective data collection. Primary nonadherence rate and blood pressure values at follow-up visits were compared between the prospective and baseline comparator groups. The primary nonadherence rate decreased from 65.5% to 22.2% when comparing the baseline and prospective groups, respectively. The mean days to prescription pick-up decreased from 24.5 to 12.56 in the baseline and prospective groups. The prospective group showed a larger decrease in systolic blood pressure (17.33 mm Hg vs. 0.75 mm Hg) and diastolic blood pressure (6.56 mm Hg vs. 2.25 mm Hg) compared with the baseline group. An online reminder through the electronic medical record appears to improve patient primary nonadherence, number of days between prescribing and prescription pick-up, and blood pressure measurements at follow-up visits. This research shows that an online reminder may be a valuable tool to improve patient primary adherence and health outcomes. Further research is needed with the use of a larger sample population to support any hypotheses about the effectiveness of the intervention. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.
Use of artificial intelligence in severe accident diagnosis for PWRs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Zheng; Okrent, D.; Kastenberg, W.E.
1995-12-31
A combination approach of an expert system and neural networks is used to implement a prototype severe accident diagnostic system which would monitor the progression of the severe accident and provide necessary plant status information to assist the plant staff in accident management during the accident. The station blackout accident in a pressurized water reactor (PWR) is used as the study case. The current phase of research focus is on distinguishing different primary system failure modes and following the accident transient before and up to vessel breach.
Flack, John M; Sica, Domenic A; Bakris, George; Brown, Angela L; Ferdinand, Keith C; Grimm, Richard H; Hall, W Dallas; Jones, Wendell E; Kountz, David S; Lea, Janice P; Nasser, Samar; Nesbitt, Shawna D; Saunders, Elijah; Scisney-Matlock, Margaret; Jamerson, Kenneth A
2010-11-01
Since the first International Society on Hypertension in Blacks consensus statement on the "Management of High Blood Pressure in African American" in 2003, data from additional clinical trials have become available. We reviewed hypertension and cardiovascular disease prevention and treatment guidelines, pharmacological hypertension clinical end point trials, and blood pressure-lowering trials in blacks. Selected trials without significant black representation were considered. In this update, blacks with hypertension are divided into 2 risk strata, primary prevention, where elevated blood pressure without target organ damage, preclinical cardiovascular disease, or overt cardiovascular disease for whom blood pressure consistently <135/85 mm Hg is recommended, and secondary prevention, where elevated blood pressure with target organ damage, preclinical cardiovascular disease, and/or a history of cardiovascular disease, for whom blood pressure consistently <130/80 mm Hg is recommended. If blood pressure is ≤10 mm Hg above target levels, monotherapy with a diuretic or calcium channel blocker is preferred. When blood pressure is >15/10 mm Hg above target, 2-drug therapy is recommended, with either a calcium channel blocker plus a renin-angiotensin system blocker or, alternatively, in edematous and/or volume-overload states, with a thiazide diuretic plus a renin-angiotensin system blocker. Effective multidrug therapeutic combinations through 4 drugs are described. Comprehensive lifestyle modifications should be initiated in blacks when blood pressure is ≥115/75 mm Hg. The updated International Society on Hypertension in Blacks consensus statement on hypertension management in blacks lowers the minimum target blood pressure level for the lowest-risk blacks, emphasizes effective multidrug regimens, and de-emphasizes monotherapy.
Foot Loading Characteristics of Chinese Bound Feet Women: A Comparative Analysis
Gu, Yaodong; Mei, Qichang; Fernandez, Justin; Li, Jianshe; Ren, Xuejun; Feng, Neng
2015-01-01
The custom of bound feet among Chinese women has existed for almost a century. This practice has influenced the daily life of Chinese women, especially during everyday locomotion. The primary aim of this study is to analyze the loading patterns of bound feet. Specifically, the plantar pressure and center of pressure were analyzed for peak pressure, contact area, force time integral, center of pressure displacement velocity and trajectory in the anterior-posterior direction via a comparison with normal feet. The key outcomes from this work were that the forefoot and rearfoot of bound feet bear the whole loading during stance phase. The center of pressure displacement velocity of bound feet was also greatly reduced with the shortening of trajectories. This suggests that the proprioceptive system adjusts motor function to adapt to new loading patterns while maintaining locomotive stability. A biomechanical understanding of bound feet may assist with prevention, treatment and rehabilitation of bound feet disorders. PMID:25884982
Proceedings of a U.S. Geological Survey pressure-sensor Workshop, Denver, Colorado, July 28-31, 1992
Wilbourn, Sammy L.
1994-01-01
The U.S. Geological Survey (USGS) conducted a Pressure Sensor Workshop, oriented toward the measurement of stage in surface waters, in Denver, Colorado, July 28-31, 1992. Twenty attendees from the U.S. Geological Survey and the National Oceanic and Atmospheric Administration gave presentations concerning their experiences with the use of pressure sensors in hydrologic investigations. This report is a compilation of the abstracts of the presentations made at the workshop. Workshop participants concluded that each of the sensors evaluated by the U.S. Geological Survey has strengths and weaknesses. Personnel contemplating the use of pressure sensors discussed at this workshop should contact workshop attendees and consult with them about their experiences with those sensors. The attendees preferred to use stilling wells with float-operated water-level sensors as the primary means for monitoring water levels. However, pressure sensor systems were favored as replacements for mercury manometers and as alternatives to stilling wells at sites where stilling wells are not practical or cost effective.
Full 3D Analysis of the GE90 Turbofan Primary Flowpath
NASA Technical Reports Server (NTRS)
Turner, Mark G.
2000-01-01
The multistage simulations of the GE90 turbofan primary flowpath components have been performed. The multistage CFD code, APNASA, has been used to analyze the fan, fan OGV and booster, the 10-stage high-pressure compressor and the entire turbine system of the GE90 turbofan engine. The code has two levels of parallel, and for the 18 blade row full turbine simulation has 87.3 percent parallel efficiency with 121 processors on an SGI ORIGIN. Grid generation is accomplished with the multistage Average Passage Grid Generator, APG. Results for each component are shown which compare favorably with test data.
Quanjel, Tessa C C; Struijs, Jeroen N; Spreeuwenberg, Marieke D; Baan, Caroline A; Ruwaard, Dirk
2018-05-09
In an attempt to deal with the pressures on the healthcare system and to guarantee sustainability, changes are needed. This study is focused on a cardiology Primary Care Plus intervention in which cardiologists provide consultations with patients in a primary care setting in order to prevent unnecessary referrals to the hospital. This study explores which patients with non-acute and low-complexity cardiology-related health complaints should be excluded from Primary Care Plus and referred directly to specialist care in the hospital. This is a retrospective observational study based on quantitative data. Data collected between January 1 and December 31, 2015 were extracted from the electronic medical record system. Logistic regression analyses were used to select patient groups that should be excluded from referral to Primary Care Plus. In total, 1525 patients were included in the analyses. Results showed that male patients, older patients, those with the referral indication 'Stable Angina Pectoris' or 'Dyspnoea' and patients whose reason for referral was 'To confirm disease' or 'Screening of unclear pathology' had a significantly higher probability of being referred to hospital care after Primary Care Plus. To achieve efficiency one should exclude patient groups with a significantly higher probability of being referred to hospital care after Primary Care Plus. NTR6629 (Data registered: 25-08-2017) (registered retrospectively).
Acoustic forcing of a liquid drop
NASA Technical Reports Server (NTRS)
Lyell, M. J.
1992-01-01
The development of systems such as acoustic levitation chambers will allow for the positioning and manipulation of material samples (drops) in a microgravity environment. This provides the capability for fundamental studies in droplet dynamics as well as containerless processing work. Such systems use acoustic radiation pressure forces to position or to further manipulate (e.g., oscillate) the sample. The primary objective was to determine the effect of a viscous acoustic field/tangential radiation pressure forcing on drop oscillations. To this end, the viscous acoustic field is determined. Modified (forced) hydrodynamic field equations which result from a consistent perturbation expansion scheme are solved. This is done in the separate cases of an unmodulated and a modulated acoustic field. The effect of the tangential radiation stress on the hydrodynamic field (drop oscillations) is found to manifest as a correction to the velocity field in a sublayer region near the drop/host interface. Moreover, the forcing due to the radiation pressure vector at the interface is modified by inclusion of tangential stresses.
Japanese Experiment Module arrival
2007-03-29
The Experiment Logistics Module Pressurized Section for the Japanese Experiment Module arrives at the Space Station Processing Facility. The logistics module is one of the components of the Japanese Experiment Module or JEM, also known as Kibo, which means "hope" in Japanese. Kibo comprises six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007.
Japanese Experiment Module arrival
2007-03-29
The Experiment Logistics Module Pressurized Section for the Japanese Experiment Module arrives at the Space Station Processing Facility for uncrating. The logistics module is one of the components of the Japanese Experiment Module or JEM, also known as Kibo, which means "hope" in Japanese. Kibo comprises six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007.
NASA Technical Reports Server (NTRS)
Edmunson, J.; Gaskin, J. A.; Danilatos, G.; Doloboff, I. J.; Effinger, M. R.; Harvey, R. P.; Jerman, G. A.; Klein-Schoder, R.; Mackie, W.; Magera, B.;
2016-01-01
The Miniaturized Variable Pressure Scanning Electron Microscope(MVP-SEM) project, funded by the NASA Planetary Instrument Concepts for the Advancement of Solar System Observations (PICASSO) Research Opportunities in Space and Earth Science (ROSES), will build upon previous miniaturized SEM designs for lunar and International Space Station (ISS) applications and recent advancements in variable pressure SEM's to design and build a SEM to complete analyses of samples on the surface of Mars using the atmosphere as an imaging medium. By the end of the PICASSO work, a prototype of the primary proof-of-concept components (i.e., the electron gun, focusing optics and scanning system)will be assembled and preliminary testing in a Mars analog chamber at the Jet Propulsion Laboratory will be completed to partially fulfill Technology Readiness Level to 5 requirements for those components. The team plans to have Secondary Electron Imaging(SEI), Backscattered Electron (BSE) detection, and Energy Dispersive Spectroscopy (EDS) capabilities through the MVP-SEM.
Loss of DHR sequences at Browns Ferry Unit One - accident-sequence analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cook, D.H.; Grene, S.R.; Harrington, R.M.
1983-05-01
This study describes the predicted response of Unit One at the Browns Ferry Nuclear Plant to a postulated loss of decay heat removal (DHR) capability following scram from full power with the power conversion system unavailable. In accident sequences without DHR capability, the residual heat removal (RHR) system functions of pressure suppression pool cooling and reactor vessel shutdown cooling are unavailable. Consequently, all decay heat energy is stored in the pressure suppression pool with a concomitant increase in pool temperature and primary containment pressure. With the assumption that DHR capability is not regained during the lengthy course of this accidentmore » sequence, the containment ultimately fails by overpressurization. Although unlikely, this catastrophic failure might lead to loss of the ability to inject cooling water into the reactor vessel, causing subsequent core uncovery and meltdown. The timing of these events and the effective mitigating actions that might be taken by the operator are discussed in this report.« less
Concept Demonstration of Dopant Selective Reactive Etching (DSRIE) in Silicon Carbide
NASA Technical Reports Server (NTRS)
Okojie, Robert S.
2015-01-01
Accurate quantification of combustor pressure dynamics for the primary purpose of experimental validation of computational fluid dynamics (CFD) codes requires the use of robust, reliable and sensitive pressure sensors that can resolve sub--pound-per-square-inch pressure levels in high temperature environments (i.e., combustor). The state of the art microfabricated piezoresistive silicon carbide (SiC) pressure sensors that we have developed are capable of operating reliably at 600 degrees Centigrade. This technology was used in support of the ARMD ISRP-ERA (NASA's Aeronautics Research Mission Directorate, Integrated System Research Project - Environmentally Responsible Aviation) program to quantify combustor thermoacoustic instabilities. The results showed that while the SiC pressure sensors survived the high temperature and measured instabilities, the diaphragm (force collector) was not thin enough to be sensitive in resolving sub-pound-per-square-inch pressures; 30 meters is the thinnest diaphragm achievable with conventional reactive ion etching (RIE) processes. Therefore, this precludes its use for sub-pound-per-square-inch pressure measurement with high fidelity. In order to effectively resolve sub-pound-per-square-inch pressures, a thinner more sensitive diaphragm (10 meters) is needed. To achieve this would require a new and innovative fabrication process technique.
2003-06-04
KENNEDY SPACE CENTER, FLA. - At Port Canaveral, the Pressurized Module of the Japanese Experiment Module (JEM) is lifted out of the ship’s cargo hold. The container transport ship carrying JEM departed May 2 from Yokohama Harbor in Japan for the voyage to the United States. The National Space Development Agency of Japan (NASDA) developed the laboratory at the Tsukuba Space Center near Tokyo. The Pressurized Module is the first element of the JEM, named "Kibo" (Hope), to be delivered to KSC. The JEM is Japan's primary contribution to the Station. It will enhance the unique research capabilities of the orbiting complex by providing an additional environment for astronauts to conduct science experiments. The JEM also includes an exposed facility (platform) for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.
Language evolution and human-computer interaction
NASA Technical Reports Server (NTRS)
Grudin, Jonathan; Norman, Donald A.
1991-01-01
Many of the issues that confront designers of interactive computer systems also appear in natural language evolution. Natural languages and human-computer interfaces share as their primary mission the support of extended 'dialogues' between responsive entities. Because in each case one participant is a human being, some of the pressures operating on natural languages, causing them to evolve in order to better support such dialogue, also operate on human-computer 'languages' or interfaces. This does not necessarily push interfaces in the direction of natural language - since one entity in this dialogue is not a human, this is not to be expected. Nonetheless, by discerning where the pressures that guide natural language evolution also appear in human-computer interaction, we can contribute to the design of computer systems and obtain a new perspective on natural languages.
Process feasibility study in support of silicon material, task 1
NASA Technical Reports Server (NTRS)
Li, K. Y.; Hansen, K. C.; Yaws, C. L.
1979-01-01
Analyses of process system properties were continued for materials involved in the alternate processes under consideration for semiconductor silicon. Primary efforts centered on physical and thermodynamic property data for dichlorosilane. The following property data are reported for dichlorosilane which is involved in processing operations for solar cell grade silicon: critical temperature, critical pressure, critical volume, critical density, acentric factor, vapor pressure, heat of vaporization, gas heat capacity, liquid heat capacity and density. Work was initiated on the assembly of a system to prepare binary gas mixtures of known proportions and to measure the thermal conductivity of these mixtures between 30 and 350 C. The binary gas mixtures include silicon source material such as silanes and halogenated silanes which are used in the production of semiconductor silicon.
Initial conceptual design study of self-critical nuclear pumped laser systems
NASA Technical Reports Server (NTRS)
Rodgers, R. J.
1979-01-01
An analytical study of self-critical nuclear pumped laser system concepts was performed. Primary emphasis was placed on reactor concepts employing gaseous uranium hexafluoride (UF6) as the fissionable material. Relationships were developed between the key reactor design parameters including reactor power level, critical mass, neutron flux level, reactor size, operating pressure, and UF6 optical properties. The results were used to select a reference conceptual laser system configuration. In the reference configuration, the 3.2 m cubed lasing volume is surrounded by a graphite internal moderator and a region of heavy water. Results of neutronics calculations yield a critical mass of 4.9 U(235) in the form (235)UF6. The configuration appears capable of operating in a continuous steady-state mode. The average gas temperature in the core is 600 K and the UF6 partial pressure within the lasing volume is 0.34 atm.
Compression Strength of Composite Primary Structural Components
NASA Technical Reports Server (NTRS)
Johnson, Eric R.; Starnes, James H., Jr. (Technical Monitor)
2000-01-01
The focus of research activities under NASA Grant NAG-1-2035 was the response and failure of thin-walled structural components. The research is applicable to the primary load carrying structure of flight vehicles, with particular emphasis on fuselage and wing'structure. Analyses and tests were performed that are applicable to the following structural components an aft pressure bulkhead, or a composite pressure dome, pressure cabin damage containment, and fuselage frames subject to crash-type loads.
NASA Technical Reports Server (NTRS)
Wing, David J.
1994-01-01
A static investigation was conducted in the static test facility of the Langley 16-Foot Transonic Tunnel of two thrust-vectoring concepts which utilize fluidic mechanisms for deflecting the jet of a two-dimensional convergent-divergent nozzle. One concept involved using the Coanda effect to turn a sheet of injected secondary air along a curved sidewall flap and, through entrainment, draw the primary jet in the same direction to produce yaw thrust vectoring. The other concept involved deflecting the primary jet to produce pitch thrust vectoring by injecting secondary air through a transverse slot in the divergent flap, creating an oblique shock in the divergent channel. Utilizing the Coanda effect to produce yaw thrust vectoring was largely unsuccessful. Small vector angles were produced at low primary nozzle pressure ratios, probably because the momentum of the primary jet was low. Significant pitch thrust vector angles were produced by injecting secondary flow through a slot in the divergent flap. Thrust vector angle decreased with increasing nozzle pressure ratio but moderate levels were maintained at the highest nozzle pressure ratio tested. Thrust performance generally increased at low nozzle pressure ratios and decreased near the design pressure ratio with the addition of secondary flow.
Chalmers, J; Chapman, N
2001-01-01
It is well established that blood pressure lowering is effective for the primary prevention of stroke and other cardiovascular disorders in subjects with blood pressures as low as 140/90 mmHg, and up to 80 years of age. Despite this knowledge, blood pressure levels are controlled in less than 25% of the hypertensive population worldwide. It has taken longer to prove that blood pressure lowering is equally effective for the prevention of recurrent stroke. The results of PROGRESS (Perindopril Protection Against Recurrent Stroke Study) have confirmed that a perindopril-based regimen in subjects with cerebrovascular disease substantially reduces the incidence of secondary stroke and primary myocardial infarction. It is daunting to recall that it has taken almost two decades for beta-blockers to be widely used for the secondary prevention of myocardial infarction, since widespread use of the PROGRESS regimen would prevent more than half a million strokes worldwide each year. The real challenge now is to implement novel and effective strategies for the control of blood pressure and other cardiovascular risk factors worldwide. Strategies should include lifestyle measures, such as stopping smoking, exercise and reducing overweight. There is a real need to identify hypertensive subjects and treat them with blood pressure lowering drugs for primary prevention. In subjects with established cardiovascular disease, consideration should be given to a range of proven interventions for secondary prevention, such as blood pressure lowering, irrespective of current blood pressure, anti-platelet drugs, statins for lowering cholesterol and glycaemic control in diabetics. Among new strategies to lower overall cardiovascular risk, consideration should be given to the development of single-pill combinations of drugs of known efficacy, including various combinations of ACE inhibitors, diuretics, beta-blockers, aspirin and statins, among others.
HealthSystem Minnesota: a leader in the Minnesota marketplace.
Greenland, C A
1997-01-01
HealthSystem Minnesota is an integrated, patient-centered, care delivery system located in the Twin Cities. In the early 1990's, as pressure built for health care providers to cut costs and increased value, Park Nicollet Clinic, Methodist Hospital, Primary Physician Network, and our other member organizations merged to form HealthSystem Minnesota. Our organization has strong relationships with several major payers, but we have chosen to remain purely a physician-led, professionally managed care delivery system. This structure allows us to focus on our patients as our first priority. This article illustrates the role HealthSystem Minnesota plays in the highly competitive Twin Cities market.
ERIC Educational Resources Information Center
Fredriksen, Birger; Fossberg, Camilla Helgø
2014-01-01
Over the next two decades, sub-Saharan Africa will face substantial pressure to expand its secondary education system. This is driven by the current low development of secondary education compared to other world regions, continued rapid population growth, the increase in the enrollment and completion rates at the primary education level, and the…
Tzeng Yih Lam; Raymond L. Czaplewski; Jong Su Yim; Kyeong Hak Lee; Sung Ho Kim; Rae Hyun Kim
2013-01-01
National Forest Inventories (NFIs) serve a primary purpose of providing crucial information for formulating national forest policy, environmental planning and reporting to international processes (Tomppo and others 2010). Pressure for timely and reliable forestry statistics urges countries to put a NFI in place or to consider alternative designs. Some countries, for...
2004-02-13
KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, workers confirm the Multi-Purpose Logistics Module Donatello is safely in place on a work stand. Previously housed in the Operations and Checkout Building, Donatello was brought into the SSPF for routine testing. This is the first time all three MPLMs (Donatello, Raffaello and Leonardo) are in the SSPF. The MPLMs were built by the Italian Space Agency, to serve as reusable logistics carriers and the primary delivery system to resupply and return station cargo requiring a pressurized environment. The third MPLM, Raffaello, is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-13
KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, the Multi-Purpose Logistics Module Donatello is slowly lowered toward a work stand. Previously housed in the Operations and Checkout Building, Donatello was brought into the SSPF for routine testing. This is the first time all three MPLMs (Donatello, Raffaello and Leonardo) are in the SSPF. The MPLMs were built by the Italian Space Agency, to serve as reusable logistics carriers and the primary delivery system to resupply and return station cargo requiring a pressurized environment. The third MPLM, Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-18
KENNEDY SPACE CENTER, FLA. - All three Multi-Purpose Logistics Modules are on the floor of the Space Station Processing Facility. This is the first time the three - Leonardo, Raffaello and Donatello -- have been in one location. Donatello has been stored in the Operations and Checkout Building since its arrival at KSC and was brought into the SSPF for routine testing. The MPLMs were built by the Italian Space Agency, to serve as reusable logistics carriers and the primary delivery system to resupply and return station cargo requiring a pressurized environment. Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-13
KENNEDY SPACE CENTER, FLA. - The Multi-Purpose Logistics Module Donatello is moved away from the payload canister in the Space Station Processing Facility. Previously housed in the Operations and Checkout Building, Donatello was brought into the SSPF for routine testing. This is the first time all three MPLMs (Donatello, Raffaello and Leonardo) are in the SSPF. The MPLMs were built by the Italian Space Agency, to serve as reusable logistics carriers and the primary delivery system to resupply and return station cargo requiring a pressurized environment. The third MPLM, Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-13
KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, workers help the Multi-Purpose Logistics Module Donatello settle onto a work stand. Previously housed in the Operations and Checkout Building, Donatello was brought into the SSPF for routine testing. This is the first time all three MPLMs (Donatello, Raffaello and Leonardo) are in the SSPF. The MPLMs were built by the Italian Space Agency, to serve as reusable logistics carriers and the primary delivery system to resupply and return station cargo requiring a pressurized environment. The third MPLM, Raffaello, is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-13
KENNEDY SPACE CENTER, FLA. - The Multi-Purpose Logistics Module Donatello is suspended by cables over the payload canister in the Space Station Processing Facility. Previously housed in the Operations and Checkout Building, Donatello was brought into the SSPF for routine testing. This is the first time all three MPLMs (Donatello, Raffaello and Leonardo) are in the SSPF. The MPLMs were built by the Italian Space Agency, to serve as reusable logistics carriers and the primary delivery system to resupply and return station cargo requiring a pressurized environment. The third MPLM, Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-18
KENNEDY SPACE CENTER, FLA. - This view reveals all three Multi-Purpose Logistics Modules on the floor of the Space Station Processing Facility. This is the first time all three - Leonardo, Raffaello and Donatello -- have been in one location. Donatello has been stored in the Operations and Checkout Building since its arrival at KSC and was brought into the SSPF for routine testing. The MPLMs were built by the Italian Space Agency, to serve as reusable logistics carriers and the primary delivery system to resupply and return station cargo requiring a pressurized environment. Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
Reversible Ammonia Sorption for the Primary Life Support System (PLSS)
NASA Technical Reports Server (NTRS)
Wojtowicz, Marek A.; Cosgrove, Joseph E.; Serio, Michael A.; Jennings, Mallory A.
2012-01-01
Results are presented on the development of regenerable trace-contaminant (TC) sorbent for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). Since ammonia is the most important TC to be captured, data presented in this paper are limited to ammonia sorption, with results relevant to other TCs to be reported at a later time. The currently available TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal. The sorbent is non-regenerable, and its use is associated with appreciable pressure drop, i.e. power consumption. The objective of this work is to demonstrate the feasibility of using vacuum-regenerable sorbents for PLSS application. In this study, several carbon sorbent monoliths were fabricated and tested. Multiple adsorption/vacuum-regeneration cycles were demonstrated at room temperature, as well as carbon surface conditioning that enhances ammonia sorption without impairing sorbent regeneration. Depending on sorbent monolith geometry, the reduction in pressure drop with respect to granular sorbent was found to be between 50% and two orders of magnitude. Resistive heating of the carbon sorbent monolith was demonstrated by applying voltage to the opposite ends of the monolith.
Rinfret, Stéphane; Lussier, Marie-Thérèse; Peirce, Anthony; Duhamel, Fabie; Cossette, Sylvie; Lalonde, Lyne; Tremblay, Chantal; Guertin, Marie-Claude; LeLorier, Jacques; Turgeon, Jacques; Hamet, Pavel
2009-05-01
Hypertension is a leading mortality risk factor yet inadequately controlled in most affected subjects. Effective programs to address this problem are lacking. We hypothesized that an information technology-supported management program could help improve blood pressure (BP) control. This randomized controlled trial included 223 primary care hypertensive subjects with mean 24-hour BP >130/80 and daytime BP >135/85 mm Hg measured with ambulatory monitoring (ABPM). Intervention subjects received a BP monitor and access to an information technology-supported adherence and BP monitoring system providing nurses, pharmacists, and physicians with monthly reports. Control subjects received usual care. The mean (+/-SD) follow-up was 348 (+/-78) and 349 (+/-84) days in the intervention and control group, respectively. The primary end point of the change in the mean 24-hour ambulatory BP was consistently greater in intervention subjects for both systolic (-11.9 versus -7.1 mm Hg; P<0.001) and diastolic BP (-6.6 versus -4.5 mm Hg; P=0.007). The proportion of subjects that achieved Canadian Guideline target BP (46.0% versus 28.6%) was also greater in the intervention group (P=0.006). We observed similar BP declines for ABPM and self-recorded home BP suggesting the latter could be an alternative for confirming BP control. The intervention was associated with more physician-driven antihypertensive dose adjustments or changes in agents (P=0.03), more antihypertensive classes at study end (P=0.007), and a trend toward improved adherence measured by prescription refills (P=0.07). This multidisciplinary information technology-supported program that provided feedback to patients and healthcare providers significantly improved blood pressure levels in a primary care setting.
He, Fu-Liang; Wang, Lei; Yue, Zhen-Dong; Zhao, Hong-Wei; Liu, Fu-Quan
2014-09-07
To evaluate the feasibility of a second parallel transjugular intrahepatic portosystemic shunt (TIPS) to reduce portal venous pressure and control complications of portal hypertension. From January 2011 to December 2012, 10 cirrhotic patients were treated for complications of portal hypertension. The demographic data, operative data, postoperative recovery data, hemodynamic data, and complications were analyzed. Ten patients underwent a primary and parallel TIPS. Technical success rate was 100% with no technical complications. The mean duration of the first operation was 89.20 ± 29.46 min and the second operation was 57.0 ± 12.99 min. The mean portal system pressure decreased from 54.80 ± 4.16 mmHg to 39.0 ± 3.20 mmHg after the primary TIPS and from 44.40 ± 3.95 mmHg to 26.10 ± 4.07 mmHg after the parallel TIPS creation. The mean portosystemic pressure gradient decreased from 43.80 ± 6.18 mmHg to 31.90 ± 2.85 mmHg after the primary TIPS and from 35.60 ± 2.72 mmHg to 15.30 ± 3.27 mmHg after the parallel TIPS creation. Clinical improvement was seen in all patients after the parallel TIPS creation. One patient suffered from transient grade I hepatic encephalopathy (HE) after the primary TIPS and four patients experienced transient grade I-II after the parallel TIPS procedure. Mean hospital stay after the first and second operations were 15.0 ± 3.71 d and 16.90 ± 5.11 d (P = 0.014), respectively. After a mean 14.0 ± 3.13 mo follow-up, ascites and bleeding were well controlled and no stenosis of the stents was found. Parallel TIPS is an effective approach for controlling portal hypertension complications.
Air-flow regulation system for a coal gasifier
Fasching, George E.
1984-01-01
An improved air-flow regulator for a fixed-bed coal gasifier is provided which allows close air-flow regulation from a compressor source even though the pressure variations are too rapid for a single primary control loop to respond. The improved system includes a primary controller to control a valve in the main (large) air supply line to regulate large slow changes in flow. A secondary controller is used to control a smaller, faster acting valve in a secondary (small) air supply line parallel to the main line valve to regulate rapid cyclic deviations in air flow. A low-pass filter with a time constant of from 20 to 50 seconds couples the output of the secondary controller to the input of the primary controller so that the primary controller only responds to slow changes in the air-flow rate, the faster, cyclic deviations in flow rate sensed and corrected by the secondary controller loop do not reach the primary controller due to the high frequency rejection provided by the filter. This control arrangement provides at least a factor of 5 improvement in air-flow regulation for a coal gasifier in which air is supplied by a reciprocating compressor through a surge tank.
Effectiveness of a medical education intervention to treat hypertension in primary care.
Martínez-Valverde, Silvia; Castro-Ríos, Angélica; Pérez-Cuevas, Ricardo; Klunder-Klunder, Miguel; Salinas-Escudero, Guillermo; Reyes-Morales, Hortensia
2012-04-01
In Mexico, hypertension is among the top five causes for visits to primary care clinics; its complications are among the main causes of emergency and hospital care. The present study reports the effectiveness of a continuing medical education (CME) intervention to improve appropriate care for hypertension, on blood pressure control of hypertensive patients in primary care clinics. A secondary data analysis was carried out using data of hypertensive patients treated by family doctors who participated in the CME intervention. The evaluation was designed as a pre-/post-intervention study with control group in six primary care clinics. The effect of the CME intervention was analysed using multiple logistic regression modelling in which the dependent variable was uncontrolled blood pressure in the post-intervention patient measurement. After the CME intervention, the net reduction of uncontrolled blood pressure between stages in the intervention group was 10.3%. The model results were that being treated by a family doctor who participated in the CME intervention reduced by 53% the probability of lack of control of blood pressure; receiving dietary recommendations reduced 57% the probability of uncontrolled blood pressure. Having uncontrolled blood pressure at the baseline stage increased the probability of lack of control in 166%, and per each unit of increase in body mass index the lack of control increased 7%. CME intervention improved the medical decision-making process to manage hypertension, thus increasing the probability of hypertensive patients to have blood pressure under control. © 2010 Blackwell Publishing Ltd.
A high-pressure atomic force microscope for imaging in supercritical carbon dioxide
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lea, Alan S.; Higgins, Steven R.; Knauss, Kevin G.
2011-04-26
A high-pressure atomic force microscope (AFM) that enables in-situ, atomic scale measurements of topography of solid surfaces in contact with supercritical CO2 (scCO2) fluids has been developed. This apparatus overcomes the pressure limitations of the hydrothermal AFM and is designed to handle pressures up to 100 atm at temperatures up to ~ 350 K. A standard optically-based cantilever deflection detection system was chosen. When imaging in compressible supercritical fluids such as scCO2, precise control of pressure and temperature in the fluid cell is the primary technical challenge. Noise levels and imaging resolution depend on minimization of fluid density fluctuations thatmore » change the fluid refractive index and hence the laser path. We demonstrate with our apparatus in-situ atomic scale imaging of a calcite (CaCO3) mineral surface in scCO2; both single, monatomic steps and dynamic processes occurring on the (10¯14) surface are presented. This new AFM provides unprecedented in-situ access to interfacial phenomena at solid-fluid interfaces under pressure.« less
Water-drinking test in primary angle-closure suspect before and after laser peripheral iridotomy.
Waisbourd, Michael; Savant, Shravan V; Sun, Yi; Martinez, Patricia; Myers, Jonathan S
2016-03-01
This study aimed to investigate whether performing a laser peripheral iridotomy in primary angle-closure suspects had an effect on the intraocular pressure response during the water-drinking test. Prospective study in a hospital setting. Primary angle-closure suspects scheduled for a laser peripheral iridotomy. Primary angle-closure suspects were evaluated before the laser peripheral iridotomy and 2 weeks after. On each visit, subjects underwent the water-drinking test. Intraocular pressure was measured every 15 min within a 1-h period. Intraocular pressure fluctuations during the water drinking test. Twenty patients were enrolled. The mean age was 58.1 years (±10.2 SD), predominantly female (n = 14, 70%). Average intraocular pressure range (maximum-minimum) during the water-drinking test increased significantly from 2.6 ± 1.1 mmHg before the laser peripheral iridotomy to 3.5 ± 1.5 mmHg after (P = 0.04). The mean difference between peak and last intraocular pressure measurements increased after the laser peripheral iridotomy was performed, from 2.5 mmHg (±1.27 SD) to 3.3 mmHg (±1.66 SD), (P = 0.057). There was no change in mean peak intraocular pressure (maximum-baseline) before and after the laser peripheral iridotomy (P = 0.87). Primary angle-closure suspects who underwent the water-drinking test had a slightly more pronounced recovery of intraocular pressure after the laser peripheral iridotomy was performed, which may be attributed to increase in the area of exposed trabecular meshwork following treatment. Differences in intraocular pressure curves before and after laser peripheral iridotomy were minimal, and therefore, the water-drinking test had limited value as a provocative test in this patient population. © 2015 Royal Australian and New Zealand College of Ophthalmologists.
Fluid design studies of integrated modular engine system
NASA Technical Reports Server (NTRS)
Frankenfield, Bruce; Carek, Jerry
1993-01-01
A study was performed to develop a fluid system design and show the feasibility of constructing an integrated modular engine (IME) configuration, using an expander cycle engine. The primary design goal of the IME configuration was to improve the propulsion system reliability. The IME fluid system was designed as a single fault tolerant system, while minimizing the required fluid components. This study addresses the design of the high pressure manifolds, turbopumps and thrust chambers for the IME configuration. A physical layout drawing was made, which located each of the fluid system components, manifolds and thrust chambers. Finally, a comparison was made between the fluid system designs of an IME system and a non-network (clustered) engine system.
ERIC Educational Resources Information Center
Yalcin, Fatma Aggul
2012-01-01
The aim of this study was to explore pre-service primary teachers' understandings of the effect of temperature and pressure on the solid-liquid phase transition of water. In the study a survey approach was used, and the sample consisted of one-hundred and three, third year pre-service primary science teachers. As a tool for data collection, a test…
NASA Astrophysics Data System (ADS)
Sutton, Tracey; Hopkins, Thomas; Remsen, Andrew; Burghart, Scott
2001-01-01
Sampling was conducted on the west Florida continental shelf ecosystem modeling site to estimate zooplankton grazing impact on primary production. Samples were collected with the high-resolution sampler, a towed array bearing electronic and optical sensors operating in tandem with a paired net/bottle verification system. A close biological-physical coupling was observed, with three main plankton communities: 1. a high-density inshore community dominated by larvaceans coincident with a salinity gradient; 2. a low-density offshore community dominated by small calanoid copepods coincident with the warm mixed layer; and 3. a high-density offshore community dominated by small poecilostomatoid and cyclopoid copepods and ostracods coincident with cooler, sub-pycnocline oceanic water. Both high-density communities were associated with relatively turbid water. Applying available grazing rates from the literature to our abundance data, grazing pressure mirrored the above bio-physical pattern, with the offshore sub-pycnocline community contributing ˜65% of grazing pressure despite representing only 19% of the total volume of the transect. This suggests that grazing pressure is highly localized, emphasizing the importance of high-resolution sampling to better understand plankton dynamics. A comparison of our grazing rate estimates with primary production estimates suggests that mesozooplankton do not control the fate of phytoplankton over much of the area studied (<5% grazing of daily primary production), but "hot spots" (˜25-50% grazing) do occur which may have an effect on floral composition.
Two Primary Standards for Low Flows of Gases
Berg, Robert F.; Tison, Stuart A.
2004-01-01
We describe two primary standards for gas flow in the range from 0.1 to 1000 μmol/s. (1 μmol/s ≅ 1.3 cm3/min at 0 °C and 1 atmosphere.) The first standard is a volumetric technique in which measurements of pressure, volume, temperature, and time are recorded while gas flows in or out of a stainless steel bellows at constant pressure. The second standard is a gravimetric technique. A small aluminum pressure cylinder supplies gas to a laminar flow meter, and the integrated throughput of the laminar flow meter is compared to the weight decrease of the cylinder. The two standards, which have standard uncertainties of 0.019 %, agree to within combined uncertainties with each other and with a third primary standard at NIST based on pressure measurements at constant volume. PMID:27366623
Determination of Barometric Altimeter Errors for the Orion Exploration Flight Test-1 Entry
NASA Technical Reports Server (NTRS)
Brown, Denise L.; Munoz, Jean-Philippe; Gay, Robert
2011-01-01
The EFT-1 mission is the unmanned flight test for the upcoming Multi-Purpose Crew Vehicle (MPCV). During entry, the EFT-1 vehicle will trigger several Landing and Recovery System (LRS) events, such as parachute deployment, based on onboard altitude information. The primary altitude source is the filtered navigation solution updated with GPS measurement data. The vehicle also has three barometric altimeters that will be used to measure atmospheric pressure during entry. In the event that GPS data is not available during entry, the altitude derived from the barometric altimeter pressure will be used to trigger chute deployment for the drogues and main parachutes. Therefore it is important to understand the impact of error sources on the pressure measured by the barometric altimeters and on the altitude derived from that pressure. There are four primary error sources impacting the sensed pressure: sensor errors, Analog to Digital conversion errors, aerodynamic errors, and atmosphere modeling errors. This last error source is induced by the conversion from pressure to altitude in the vehicle flight software, which requires an atmosphere model such as the US Standard 1976 Atmosphere model. There are several secondary error sources as well, such as waves, tides, and latencies in data transmission. Typically, for error budget calculations it is assumed that all error sources are independent, normally distributed variables. Thus, the initial approach to developing the EFT-1 barometric altimeter altitude error budget was to create an itemized error budget under these assumptions. This budget was to be verified by simulation using high fidelity models of the vehicle hardware and software. The simulation barometric altimeter model includes hardware error sources and a data-driven model of the aerodynamic errors expected to impact the pressure in the midbay compartment in which the sensors are located. The aerodynamic model includes the pressure difference between the midbay compartment and the free stream pressure as a function of altitude, oscillations in sensed pressure due to wake effects, and an acoustics model capturing fluctuations in pressure due to motion of the passive vents separating the barometric altimeters from the outside of the vehicle.
Fitzek, H; Schroettner, H; Wagner, J; Hofer, F; Rattenberger, J
2016-04-01
In environmental scanning electron microscopy applications in the kPa regime are of increasing interest for the investigation of wet and biological samples, because neither sample preparation nor extensive cooling are necessary. Unfortunately, the applications are limited by poor image quality. In this work the image quality at high pressures of a FEI Quanta 600 (field emission gun) and a FEI Quanta 200 (thermionic gun) is greatly improved by optimizing the pressure limiting system and the secondary electron (SE) detection system. The scattering of the primary electron beam strongly increases with pressure and thus the image quality vanishes. The key to high-image quality at high pressures is to reduce scattering as far as possible while maintaining ideal operation conditions for the SE-detector. The amount of scattering is reduced by reducing both the additional stagnation gas thickness (aSGT) and the environmental distance (ED). A new aperture holder is presented that significantly reduces the aSGT while maintaining the same field-of-view (FOV) as the original design. With this aperture holder it is also possible to make the aSGT even smaller at the expense of a smaller FOV. A new blade-shaped SE-detector is presented yielding better image quality than usual flat SE-detectors. The electrode of the new SE detector is positioned on the sample table, which allows the SE-detector to operate at ideal conditions regardless of pressure and ED. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.
CRYOTE (Cryogenic Orbital Testbed) Concept
NASA Technical Reports Server (NTRS)
Gravlee, Mari; Kutter, Bernard; Wollen, Mark; Rhys, Noah; Walls, Laurie
2009-01-01
Demonstrating cryo-fluid management (CFM) technologies in space is critical for advances in long duration space missions. Current space-based cryogenic propulsion is viable for hours, not the weeks to years needed by space exploration and space science. CRYogenic Orbital TEstbed (CRYOTE) provides an affordable low-risk environment to demonstrate a broad array of critical CFM technologies that cannot be tested in Earth's gravity. These technologies include system chilldown, transfer, handling, health management, mixing, pressure control, active cooling, and long-term storage. United Launch Alliance is partnering with Innovative Engineering Solutions, the National Aeronautics and Space Administration, and others to develop CRYOTE to fly as an auxiliary payload between the primary payload and the Centaur upper stage on an Atlas V rocket. Because satellites are expensive, the space industry is largely risk averse to incorporating unproven systems or conducting experiments using flight hardware that is supporting a primary mission. To minimize launch risk, the CRYOTE system will only activate after the primary payload is separated from the rocket. Flying the testbed as an auxiliary payload utilizes Evolved Expendable Launch Vehicle performance excess to cost-effectively demonstrate enhanced CFM.
Numerical Hydraulic Study on Seawater Cooling System of Combined Cycle Power Plant
NASA Astrophysics Data System (ADS)
Kim, J. Y.; Park, S. M.; Kim, J. H.; Kim, S. W.
2010-06-01
As the rated flow and pressure increase in pumping facilities, a proper design against surges and severe cavitations in the pipeline system is required. Pressure surge due to start-up, shut-down process and operation failure causes the water hammer in upstream of the closing valve and the cavitational hammer in downstream of the valve. Typical cause of water hammer is the urgent closure of valves by breakdown of power supply and unexpected failure of pumps. The abrupt changes in the flow rate of the liquid results in high pressure surges in upstream of the valves, thus kinetic energy is transformed into potential energy which leads to the sudden increase of the pressure that is called as water hammer. Also, by the inertia, the liquid continues to flow downstream of the valve with initial speed. Accordingly, the pressure decreases and an expanding vapor bubble known as column separation are formed near the valve. In this research, the hydraulic study on the closed cooling water heat exchanger line, which is the one part of the power plant, is introduced. The whole power plant consists of 1,200 MW combined power plant and 220,000 m3/day desalination facility. Cooling water for the plant is supplied by sea water circulating system with a capacity of 29 m3/s. The primary focus is to verify the steady state hydraulic capacity of the system. The secondary is to quantify transient issues and solutions in the system. The circuit was modeled using a commercial software. The stable piping network was designed through the hydraulic studies using the simulation for the various scenarios.
Vaughan, T. J.; Haugh, M. G.; McNamara, L. M.
2013-01-01
Bone continuously adapts its internal structure to accommodate the functional demands of its mechanical environment and strain-induced flow of interstitial fluid is believed to be the primary mediator of mechanical stimuli to bone cells in vivo. In vitro investigations have shown that bone cells produce important biochemical signals in response to fluid flow applied using parallel-plate flow chamber (PPFC) systems. However, the exact mechanical stimulus experienced by the cells within these systems remains unclear. To fully understand this behaviour represents a most challenging multi-physics problem involving the interaction between deformable cellular structures and adjacent fluid flows. In this study, we use a fluid–structure interaction computational approach to investigate the nature of the mechanical stimulus being applied to a single osteoblast cell under fluid flow within a PPFC system. The analysis decouples the contribution of pressure and shear stress on cellular deformation and for the first time highlights that cell strain under flow is dominated by the pressure in the PPFC system rather than the applied shear stress. Furthermore, it was found that strains imparted on the cell membrane were relatively low whereas significant strain amplification occurred at the cell–substrate interface. These results suggest that strain transfer through focal attachments at the base of the cell are the primary mediators of mechanical signals to the cell under flow in a PPFC system. Such information is vital in order to correctly interpret biological responses of bone cells under in vitro stimulation and elucidate the mechanisms associated with mechanotransduction in vivo. PMID:23365189
Delvau, N; Penaloza, A; Liistro, G; Thys, F; Delattre, I K; Hantson, Philippe; Gianello, P; Roy, P M
2018-06-01
In an experimental study on carbon monoxide (CO) exposure in swine, we aimed to compare the influence of oxygen therapy using a non-rebreathing mask (NRM) to continuous positive airway pressure (CPAP) and two pressure support ventilation (PSV) devices on the decrease of the terminal elimination half-life of carboxyhemoglobin (COHb t 1/2 ). This was the primary outcome. Eight spontaneously breathing pigs were sedated by propofol and exposed to 940 ppm CO several times (n = 25) to obtain COHb levels of 30%. CPAPb (high flow open system, CPAP Boussignac® [7.5 cmH 2 O]), PSV-Vy (open system, Vylife Boussignac®), and PSV-Leg (closed system, Legendair® [inspiratory/expiratory airway pressure 12/4 cmH 2 O]) devices were used in a randomized order and compared to NRM (O 2 at 15 l min -1 ) and atmospheric air (AA). The primary outcome was COHb t 1/2 . Multiple comparisons were performed using Dunn's tests. Median FiO 2 and minute ventilation were significantly higher in the PSV-Leg group than the NRM group (p < 0.05). Median COHb t 1/2 was 251, 85, 82, 93, and 58 min for AA, NRM, CPAPb, PSV-Vy, and PSV-Leg, respectively. All the interventions were superior to AA in terms of CO elimination (p < 0.001), but there was no statistically significant difference between CPAP or PSV and NRM. There was only a trend between PSV-Leg and NRM (p = 0.18). The median AUCs for ln (COHb) × time (h) were 170, 79, 83, 100, and 64 for AA, NRM, CPAPb, PSV-Vy, and PSV-Leg respectively, with a statistically significant difference only between AA and PSV-Leg (p = 0.002). In conclusion, in our study on CO intoxication in swine, the use of the closed PSV-Leg system led to the shortest COHb t 1/2 . These results suggest that PSV-Leg can be more efficient than NRM in eliminating CO and support the design of a clinical study to assess this hypothesis.
Pathophysiology of hypopituitarism in the setting of brain injury
Dusick, Joshua R.; Wang, Christina; Cohan, Pejman; Swerdloff, Ronald
2014-01-01
The complex pathophysiology of traumatic brain injury (TBI) involves not only the primary mechanical event but also secondary insults such as hypotension, hypoxia, raised intracranial pressure and changes in cerebral blood flow and metabolism. It is increasingly evident that these initial insults as well as transient events and treatments during the early injury phase can impact hypothalamic-pituitary function both acutely and chronically after injury. In turn, untreated pituitary hormonal dysfunction itself can further hinder recovery from brain injury. Secondary adrenal insufficiency, although typically reversible, occurs in up to 50% of intubated TBI victims and is associated with lower systemic blood pressure. PMID:18481181
NASA Astrophysics Data System (ADS)
Nwe, Y. Y.; Grundmann, G.
1990-11-01
Fluid inclusions in emeralds from the Habachtal, Central Tauern Window, have been studied by microthermometry. Results allow a detailed reconstruction of trapping history and evolution of the metamorphic fluids during the Middle Alpine Tauernkristallisation metamorphic event and some of the subsequent cooling period. Five different types of fluid inclusions, corresponding to at least five trapping periods, have been distinguished. In general, the earliest primary (type 1) inclusions, which occur as negative crystals or thin long tubes, are represented by low salinity ( < 10 wt. % NaCl equivalent) aqueous fluids with or without CO 2 with up to XCO 2 ≈ 0.04. Later primary type 2 inclusions are distinguished by different morphologies and distribution patterns. Lower salinity CO 2-free brines and CO 2-bearing denser inclusions with higher CO 2 contents (up to XCO 2 ≈ 0.11) are characteristic of this stage. The type 2 inclusions may also occur as pseudosecondary arrays. The effects of necking have been studied, and found to be considerable in the type 1 primary inclusions. This mechanism has occasionally resulted in the appearance of almost pure CO 2 fluids. The possibility of fluid immiscibility has been examined, and rejected, for the apparent "coexistence" of primary brine and CO 2-bearing inclusions. Instead, mixing of fluids which fluctuated between two different compositions is proposed. The fluctuation was probably due to the sequence of hydration reactions during the Tauernkristallisation. Maximum trapping pressures (3.6 kbar) obtained for stage 1 of the Tauernkristallisation are thought to represent a situation where sublithostatic fluid pressures exested in shear zones during the crystallisation period of many of the emerald cores and coexisting biotite and actinolite. Maximum fluid pressures of 7 kbar were obtained from the type 2 inclusions. This is similar to pressure estimates obtained from mineral equilibria. At least four phases of deformation are indicated by the trapping history. A pressure-temperature-time path for the Tauernkristallisation and the subsequent cooling/uplift period has been constructed for the Habachtal area, using the maximum pressure estimates obtained in this work together with previously existing data. In the cooling period, fluid pressures lower than the lithostatic load again prevailed. This difference, about 1-2 kbar, was probably due to late stage fracturing and/or the development of an open system. At least two more phases of minor deformation and three more stages of entrapment have been defined for this period. During this time, fluids gradually evolved towards more CO 2-poor, and less saline compositions. The present work shows that the possibility of fluctuations in fluid pressures must be considered seriously when attempting to define the PT cooling path from fluid inclusions in metamorphic rocks, especially those in shear zones. Postulations of retrograde PT paths based on fluid inclusions alone may result in pressure estimates which are too low.
Combining pressure and temperature control in dynamics on energy landscapes
NASA Astrophysics Data System (ADS)
Hoffmann, Karl Heinz; Christian Schön, J.
2017-05-01
Complex systems from science, technology or mathematics usually appear to be very different in their specific dynamical evolution. However, the concept of an energy landscape with its basins corresponding to locally ergodic regions separated by energy barriers provides a unifying approach to the description of complex systems dynamics. In such systems one is often confronted with the task to control the dynamics such that a certain basin is reached with the highest possible probability. Typically one aims for the global minimum, e.g. when dealing with global optimization problems, but frequently other local minima such as the metastable compounds in materials science are of primary interest. Here we show how this task can be solved by applying control theory using magnesium fluoride as an example system, where different modifications of MgF2 are considered as targets. In particular, we generalize previous work restricted to temperature controls only and present controls which simultaneously adjust temperature and pressure in an optimal fashion.
Internal performance characteristics of vectored axisymmetric ejector nozzles
NASA Technical Reports Server (NTRS)
Lamb, Milton
1993-01-01
A series of vectoring axisymmetric ejector nozzles were designed and experimentally tested for internal performance and pumping characteristics at NASA-Langley Research Center. These ejector nozzles used convergent-divergent nozzles as the primary nozzles. The model geometric variables investigated were primary nozzle throat area, primary nozzle expansion ratio, effective ejector expansion ratio (ratio of shroud exit area to primary nozzle throat area), ratio of minimum ejector area to primary nozzle throat area, ratio of ejector upper slot height to lower slot height (measured on the vertical centerline), and thrust vector angle. The primary nozzle pressure ratio was varied from 2.0 to 10.0 depending upon primary nozzle throat area. The corrected ejector-to-primary nozzle weight-flow ratio was varied from 0 (no secondary flow) to approximately 0.21 (21 percent of primary weight-flow rate) depending on ejector nozzle configuration. In addition to the internal performance and pumping characteristics, static pressures were obtained on the shroud walls.
JEM Experiment Logistics Module Pressurized Section
2007-04-02
An overhead crane moves the JEM Experiment Logistics Module Pressurized Section above the floor of the Space Station Processing Facility to a scale for weight and center-of-gravity measurements. The module will then be moved to a work stand. The logistics module is one of the components of the Japanese Experiment Module or JEM, also known as Kibo, which means "hope" in Japanese. Kibo comprises six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007.
JEM Experiment Logistics Module Pressurized Section
2007-04-02
In the Space Station Processing Facility, an overhead crane moves the JEM Experiment Logistics Module Pressurized Section toward a scale (at left) for weight and center-of-gravity measurements. The module will then be moved to a work stand. The logistics module is one of the components of the Japanese Experiment Module or JEM, also known as Kibo, which means "hope" in Japanese. Kibo comprises six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007.
JEM Experiment Logistics Module Pressurized Section
2007-04-02
The JEM Experiment Logistics Module Pressurized Section is lifted from its shipping crate in the Space Station Processing Facility. The module will be moved to a scale for weight and center-of-gravity measurements and then to a work stand. The logistics module is one of the components of the Japanese Experiment Module or JEM, also known as Kibo, which means "hope" in Japanese. Kibo comprises six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007.
JEM Experiment Logistics Module Pressurized Section
2007-04-02
In the Space Station Processing Facility, an overhead crane lifts the JEM Experiment Logistics Module Pressurized Section from its shipping container and moves it toward a scale for weight and center-of-gravity measurements. The module will then be moved to a work stand. The logistics module is one of the components of the Japanese Experiment Module or JEM, also known as Kibo, which means "hope" in Japanese. Kibo comprises six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007.
Godwin, Marshall; Dawes, Martin; Kiss, Alexander; Tobe, Sheldon W; Grant, F Curry; Kaczorowski, Janusz
2011-01-01
Objective To compare the quality and accuracy of manual office blood pressure and automated office blood pressure using the awake ambulatory blood pressure as a gold standard. Design Multi-site cluster randomised controlled trial. Setting Primary care practices in five cities in eastern Canada. Participants 555 patients with systolic hypertension and no serious comorbidities under the care of 88 primary care physicians in 67 practices in the community. Interventions Practices were randomly allocated to either ongoing use of manual office blood pressure (control group) or automated office blood pressure (intervention group) using the BpTRU device. The last routine manual office blood pressure (mm Hg) was obtained from each patient’s medical record before enrolment. Office blood pressure readings were compared before and after enrolment in the intervention and control groups; all readings were also compared with the awake ambulatory blood pressure. Main outcome measure Difference in systolic blood pressure between awake ambulatory blood pressure minus automated office blood pressure and awake ambulatory blood pressure minus manual office blood pressure. Results Cluster randomisation allocated 31 practices (252 patients) to manual office blood pressure and 36 practices (303 patients) to automated office blood pressure measurement. The most recent routine manual office blood pressure (149.5 (SD 10.8)/81.4 (8.3)) was higher than automated office blood pressure (135.6 (17.3)/77.7 (10.9)) (P<0.001). In the control group, routine manual office blood pressure before enrolment (149.9 (10.7)/81.8 (8.5)) was reduced to 141.4 (14.6)/80.2 (9.5) after enrolment (P<0.001/P=0.01), but the reduction in the intervention group from manual office to automated office blood pressure was significantly greater (P<0.001/P=0.02). On the first study visit after enrolment, the estimated mean difference for the intervention group between the awake ambulatory systolic/diastolic blood pressure and automated office blood pressure (−2.3 (95% confidence interval −0.31 to −4.3)/−3.3 (−2.7 to −4.4)) was less (P=0.006/P=0.26) than the difference in the control group between the awake ambulatory blood pressure and the manual office blood pressure (−6.5 (−4.3 to −8.6)/−4.3 (−2.9 to −5.8)). Systolic/diastolic automated office blood pressure showed a stronger (P<0.001) within group correlation (r=0.34/r=0.56) with awake ambulatory blood pressure after enrolment compared with manual office blood pressure versus awake ambulatory blood pressure before enrolment (r=0.10/r= 0.40); the mean difference in r was 0.24 (0.12 to 0.36)/0.16 (0.07 to 0.25)). The between group correlation comparing diastolic automated office blood pressure and awake ambulatory blood pressure (r=0.56) was stronger (P<0.001) than that for manual office blood pressure versus awake ambulatory blood pressure (r=0.30); the mean difference in r was 0.26 (0.09 to 0.41). Digit preference with readings ending in zero was substantially reduced by use of automated office blood pressure. Conclusion In compliant, otherwise healthy, primary care patients with systolic hypertension, introduction of automated office blood pressure into routine primary care significantly reduced the white coat response compared with the ongoing use of manual office blood pressure measurement. The quality and accuracy of automated office blood pressure in relation to the awake ambulatory blood pressure was also significantly better when compared with manual office blood pressure. Trial registration Clinical trials NCT 00214053. PMID:21300709
Solubility of crude oil in methane as a function of pressure and temperature
Price, L.C.; Wenger, L.M.; Ging, T.; Blount, C.W.
1983-01-01
The solubility of a 44?? API (0.806 sp. gr.) whole crude oil has been measured in methane with water present at temperatures of 50 to 250??C and pressures of 740 to 14,852 psi, as have the solubilities of two high molecular weight petroleum distillation fractions at temperatures of 50 to 250??C and pressures of 4482 to 25,266 psi. Both increases in pressure and temperature increase the solubility of crude oil and petroleum distillation fractions in methane, the effect of pressure being greater than that of temperature. Unexpectedly high solubility levels (0.5-1.5 grams of oil per liter of methane-at laboratory temperature and pressure) were measured at moderate conditions (50-200??C and 5076-14504 psi). Similar results were found for the petroleum distillation fractions, one of which was the highest molecular weight material of petroleum (material boiling above 266??C at 6 microns pressure). Unexpectedly mild conditions (100??C and 15,200 psi; 200??C and 7513 psi) resulted in cosolubility of crude oil and methane. Under these conditions, samples of the gas-rich phase gave solubility values of 4 to 5 g/l, or greater. Qualitative analyses of the crude-oil solute samples showed that at low pressure and temperature equilibration conditions, the solute condensate would be enriched in C5-C15 range hydrocarbons and in saturated hydrocarbons in the C15+ fraction. With increases in temperature and especially pressure, these tendencies were reversed, and the solute condensate became identical to the starting crude oil. The data of this study, compared to that of previous studies, shows that methane, with water present, has a much greater carrying capacity for crude oil than in dry systems. The presence of water also drastically lowers the temperature and pressure conditions required for cosolubility. The data of this and/or previous studies demonstrate that the addition of carbon dioxide, ethane, propane, or butane to methane also has a strong positive effect on crude oil solubility, as does the presence of fine grained rocks. The n-paraffin distributions (as well as the overall composition) of the solute condensates are controlled by the temperature and pressure of solution and exsolution, as well as by the composition of the original starting material. It appears quite possible that primary migration by gaseous solution could 'strip' a source rock of crude-oil like components leaving behind a bitumen totally unlike the migrated crude oil. The data of this study demonstrate previous criticisms of primary petroleum migration by gas solution are invalid; that primary migration by gaseous solution cannot occur because methane cannot dissolve sufficient volumes of crude oil or cannot dissolve the highest molecular weight components of petroleum (tars and asphaltenes). ?? 1983.
Using handgrip strength to screen for diabetes in developing countries.
Eckman, Molly; Gigliotti, Christopher; Sutermaster, Staci; Butler, Peter J; Mehta, Khanjan
2016-01-01
Lack of access to healthcare in the developing world has created a need for locally-based primary and pre-primary healthcare systems. Many regions of the world have adopted Community Health Worker (CHW) programmes, but volunteers in these programmes lack the tools and resources to screen for disease. Because of its simplicity of operation, handgrip strength (HGS) measurements have the potential to be an affordable and effective screening tool for conditions that cause muscle weakness in this context. In the study described in this report, translators were used to collect data on age, gender, height, weight, blood pressure, HGS and key demographic data. HGS was significantly lower for diabetics than patients without diabetes. A simple binary logistic model was created that used HGS, age, blood pressure and BMI to predict a patient's probability of having diabetes. This study develops a predictive model for diabetes using HGS and other basic health measurements and shows that HGS-based screening is a viable method of early detection of diabetes.
Realization of the medium and high vacuum primary standard in CENAM, Mexico
NASA Astrophysics Data System (ADS)
Torres-Guzman, J. C.; Santander, L. A.; Jousten, K.
2005-12-01
A medium and high vacuum primary standard, based on the static expansion method, has been set up at Centro Nacional de Metrología (CENAM), Mexico. This system has four volumes and covers a measuring range of 1 × 10-5 Pa to 1 × 103 Pa of absolute pressure. As part of its realization, a characterization was performed, which included volume calibrations, several tests and a bilateral key comparison. To determine the expansion ratios, two methods were applied: the gravimetric method and the method with a linearized spinning rotor gauge. The outgassing ratios for the whole system were also determined. A comparison was performed with Physikalisch-Technische Bundesanstalt (comparison SIM-Euromet.M.P-BK3). By means of this comparison, a link has been achieved with the Euromet comparison (Euromet.M.P-K1.b). As a result, it is concluded that the value obtained at CENAM is equivalent to the Euromet reference value, and therefore the design, construction and operation of CENAM's SEE-1 vacuum primary standard were successful.
Purdy, Phillip D; South, Charles; Klucznik, Richard P; Liu, Kenneth C; Novakovic, Robin L; Puri, Ajit S; Pride, G Lee; Aagaard-Kienitz, Beverly; Ray, Abishek; Elliott, Alan C
2017-01-01
Purpose Monitoring of blood pressure (BP) during procedures is variable, depending on multiple factors. Common methods include sphygmomanometer (BP cuff), separate radial artery catheterization, and side port monitoring of an indwelling sheath. Each means of monitoring has disadvantages, including time consumption, added risk, and signal dampening due to multiple factors. We sought an alternative approach to monitoring during procedures in the catheterization laboratory. Methods A new technology involving a 330 µm fiberoptic sensor embedded in the wall of a sheath structure was tested against both radial artery catheter and sphygmomanometer readings obtained simultaneous with readings recorded from the pressure sensing system (PSS). Correlations and Bland–Altman analysis were used to determine whether use of the PSS could substitute for these standard techniques. Results The results indicated highly significant correlations in systolic, diastolic, and mean arterial pressures (MAP) when compared against radial artery catheterization (p<0.0001), and MAP means differed by <4%. Bland–Altman analysis of the data suggested that the sheath measurements can replace a separate radial artery catheter. While less striking, significant correlations were seen when PSS readings were compared against BP cuff readings. Conclusions The PSS has competitive functionality to that seen with a dedicated radial artery catheter for BP monitoring and is available immediately on sheath insertion without the added risk of radial catheterization. The sensor is structurally separated from the primary sheath lumen and readings are unaffected by device introduction through the primary lumen. Time delays and potential complications from radial artery catheterization are avoided. PMID:27422970
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rashchenko, Sergey V., E-mail: rashchenko@igm.nsc.ru; Litasov, Konstantin D.; Novosibirsk State University, 630090 Novosibirsk
2015-04-14
The pressure-induced shift of Sm:SrB{sub 4}O{sub 7} fluorescence was calibrated in a quasi-hydrostatic helium medium up to 60 GPa using the recent Sm-doped yttrium-aluminum garnet primary pressure scale as a reference. The resulting calibration can be written as P = −2836/14.3 [(1 + Δλ/685.51){sup −14.3 }− 1]. Previous calibrations based on the internally inconsistent primary scales are revised, and, after appropriate correction, found to agree with the proposed one. The calibration extended to 120 GPa was also performed using corrected previous data and can be written as P = 4.20 Δλ (1 + 0.020 Δλ)/(1 + 0.036 Δλ)
Anchala, Raghupathy; Kaptoge, Stephen; Pant, Hira; Di Angelantonio, Emanuele; Franco, Oscar H.; Prabhakaran, D.
2015-01-01
Background Randomized control trials from the developed world report that clinical decision support systems (DSS) could provide an effective means to improve the management of hypertension (HTN). However, evidence from developing countries in this regard is rather limited, and there is a need to assess the impact of a clinical DSS on managing HTN in primary health care center (PHC) settings. Methods and Results We performed a cluster randomized trial to test the effectiveness and cost‐effectiveness of a clinical DSS among Indian adult hypertensive patients (between 35 and 64 years of age), wherein 16 PHC clusters from a district of Telangana state, India, were randomized to receive either a DSS or a chart‐based support (CBS) system. Each intervention arm had 8 PHC clusters, with a mean of 102 hypertensive patients per cluster (n=845 in DSS and 783 in CBS groups). Mean change in systolic blood pressure (SBP) from baseline to 12 months was the primary endpoint. The mean difference in SBP change from baseline between the DSS and CBS at the 12th month of follow‐up, adjusted for age, sex, height, waist, body mass index, alcohol consumption, vegetable intake, pickle intake, and baseline differences in blood pressure, was −6.59 mm Hg (95% confidence interval: −12.18 to −1.42; P=0.021). The cost‐effective ratio for CBS and DSS groups was $96.01 and $36.57 per mm of SBP reduction, respectively. Conclusion Clinical DSS are effective and cost‐effective in the management of HTN in resource‐constrained PHC settings. Clinical Trial Registration URL: http://www.ctri.nic.in. Unique identifier: CTRI/2012/03/002476. PMID:25559011
NASA Astrophysics Data System (ADS)
Loughrey, Lara; Marshall, Dan; Jones, Peter; Millsteed, Paul; Main, Arthur
2012-06-01
The Emmaville-Torrington emeralds were first discovered in 1890 in quartz veins hosted within a Permian metasedimentary sequence, consisting of meta-siltstones, slates and quartzites intruded by pegmatite and aplite veins from the Moule Granite. The emerald deposit genesis is consistent with a typical granite-related emerald vein system. Emeralds from these veins display colour zonation alternating between emerald and clear beryl. Two fluid inclusion types are identified: three-phase (brine+vapour+halite) and two-phase (vapour+liquid) fluid inclusions. Fluid inclusion studies indicate the emeralds were precipitated from saline fluids ranging from approximately 33 mass percent NaCl equivalent. Formational pressures and temperatures of 350 to 400 °C and approximately 150 to 250 bars were derived from fluid inclusion and petrographic studies that also indicate emerald and beryl precipitation respectively from the liquid and vapour portions of a two-phase (boiling) system. The distinct colour zonations observed in the emerald from these deposits is the first recorded emerald locality which shows evidence of colour variation as a function of boiling. The primary three-phase and primary two-phase FITs are consistent with alternating chromium-rich `striped' colour banding. Alternating emerald zones with colourless beryl are due to chromium and vanadium partitioning in the liquid portion of the boiling system. The chemical variations observed at Emmaville-Torrington are similar to other colour zoned emeralds from other localities worldwide likely precipitated from a boiling system as well.
Air cleaning performance of a new environmentally controlled primary crusher operator booth.
Organiscak, J A; Cecala, A B; Zimmer, J A; Holen, B; Baregi, J R
2016-02-01
The National Institute for Occupational Safety and Health (NIOSH) cooperated with 3M Company in the design and testing of a new environmentally controlled primary crusher operator booth at the company's Wausau granite quarry near Wausau, WI. This quarry had an older crusher booth without a central heating, ventilation and air conditioning (HVAC) system, and without an air filtration and pressurization system. A new replacement operator booth was designed and installed by 3M based on design considerations from past NIOSH research on enclosed cab filtration systems. NIOSH conducted pre-testing of the old booth and post-testing of the new booth to assess the new filtration and pressurization system's effectiveness in controlling airborne dusts and particulates. The booth's dust and particulate control effectiveness is described by its protection factor, expressed as a ratio of the outside to inside concentrations measured during testing. Results indicate that the old booth provided negligible airborne respirable dust protection and low particulate protection from the outside environment. The newly installed booth provided average respirable dust protection factors from 2 to 25 over five shifts of dust sampling with occasional worker ingress and egress from the booth, allowing some unfiltered contaminants to enter the enclosure. Shorter-term particle count testing outside and inside the booth under near-steady-state conditions, with no workers entering or exiting the booth, resulted in protection factors from 35 to 127 on 0.3- to 1.0-μm respirable size particulates under various HVAC airflow operating conditions.
Review on pressure swirl injector in liquid rocket engine
NASA Astrophysics Data System (ADS)
Kang, Zhongtao; Wang, Zhen-guo; Li, Qinglian; Cheng, Peng
2018-04-01
The pressure swirl injector with tangential inlet ports is widely used in liquid rocket engine. Commonly, this type of pressure swirl injector consists of tangential inlet ports, a swirl chamber, a converging spin chamber, and a discharge orifice. The atomization of the liquid propellants includes the formation of liquid film, primary breakup and secondary atomization. And the back pressure and temperature in the combustion chamber could have great influence on the atomization of the injector. What's more, when the combustion instability occurs, the pressure oscillation could further affects the atomization process. This paper reviewed the primary atomization and the performance of the pressure swirl injector, which include the formation of the conical liquid film, the breakup and atomization characteristics of the conical liquid film, the effects of the rocket engine environment, and the response of the injector and atomization on the pressure oscillation.
Space shuttle Production Verification Motor 1 (PV-1) static fire
NASA Technical Reports Server (NTRS)
1989-01-01
All inspection and instrumentation data indicate that the PV-1 static test firing conducted 18 Aug. 1988 was successful. With the exception of the intentionally flawed joints and static test modifications, PV-1 was flight configuration. Fail-safe flaws guaranteeing pressure to test the sealing capability of primary O-rings were included in the aft field joint, case-to-nozzle joint, and nozzle internal Joint 5. The test was conducted at ambient conditions, with the exception of the field joints and case/nozzle joints which were maintained at a minimum of 75 F. Ballistics performance values were within specification requirements. The PV-1 motor exhibited chamber pressure oscillations similar to previously tested Space Shuttle redesigned solid rocket motors, particularly QM-7. The first longitudinal mode oscillations experienced by PV-1 were the strongest ever measured in a Space Shuttle motor. Investigation into this observation is being conducted. Joint insulation performed as designed with no evidence of gas flow within unflawed forward field joints. The intentionally flawed center and aft case field joint insulation performance was excellent. There was no evidence of hot gas past the center field joint capture feature O-ring, the case-to-nozzle joint primary O-ring, or the aft field joint primary O-ring. O-ring seals and barriers with assured pressure at the flaws showed erosion and heat effect, but all sealed against passage of hot gases with the exception of the aft field joint capture feature O-ring. There was no evidence of erosion, heat effect, or blowby on any O-ring seals or barriers at the unflawed joints. Nozzle performance was nominal with typical erosion. Post-test examination revealed that the forward nose ring was of the old high performance motor design configuration with the 150-deg ply angle. All nozzle components remained intact for post-test evaluation. The thrust vector control system operated correctly. The water deluge system, CO2 quench, and other test equipment performed as planned during all required test operations.
Pressure Sores and Systemic Inflammatory Response Syndrome: UC Davis Quality Improvement Initiative.
Jairam, Abhishek; Song, Ping; Patel, Nirav B; Wong, Michael S
2018-05-01
The National Pressure Ulcer Advisory Panel estimates pressure sore care to approach $11 billion annually. It is not uncommon for these patients to present to the emergency department (ED) with a chief concern of a pressure sore, while concurrently carrying an undiagnosed infectious process that is the culprit for the acute presentation, rather than the chronic pressure injury. We aim to identify patients who met systemic inflammatory response syndrome (SIRS) criteria at ED presentation who were referred to plastic and reconstructive surgery for pressure sore debridement prior to a complete medical workup. We hypothesize that a restructuring of the ED triaging system would help conserve hospital resources, reduce costs of pressure sore management, and improve patient care and outcomes by first treating primary, underlying pathologies. This is a retrospective chart review of 36 patients who presented to the University of California, Davis Medical Center Emergency Department with a pressure sore and met SIRS criteria, but obtained a plastic surgery consult prior to a full medical workup. We defined SIRS based on standardized criteria: temperature greater than 100.4°F or less than 96.8°F, pulse rate greater than 90 beats/min, respiratory rate greater than 20 breaths/min or PaCO2 less than 32 mm Hg, white blood cell count greater than 12,000, less than 4000, or greater than 10% bands. Fifty percent of patients (18/36) met SIRS criteria at ED presentation for their pressure sores. Of these SIRS patients, 9 (50%) had a diagnosis of urinary tract infection or urosepsis, 6 (33.3%) had sepsis of undefined origin, and 3 (16.7%) had other diagnoses such as osteomyelitis or acute respiratory distress syndrome. Half of patients consulted while in the University of California, Davis Medical Center Emergency Department with pressure sores met SIRS criteria and received a plastic and reconstructive surgery consult prior to a full medical workup. We propose a new algorithm for triaging pressure sore patients be established in our institution that emphasizes a medical and surgical collaborative approach in order to reduce cost, conserve resources, and improve patient care.
Care for Canada's frail elderly population: Fragmentation or integration?
Bergman, H; Béland, F; Lebel, P; Contandriopoulos, A P; Tousignant, P; Brunelle, Y; Kaufman, T; Leibovich, E; Rodriguez, R; Clarfield, M
1997-01-01
Budget constraints, technological advances and a growing elderly population have resulted in major reforms in health care systems across Canada. This has led to fewer and smaller acute care hospitals and increasing pressure on the primary care and continuing care networks. The present system of care for the frail elderly, who are particularly vulnerable, is characterized by fragmentation of services, negative incentives and the absence of accountability. This is turn leads to the inappropriate and costly use of health and social services, particularly in acute care hospitals and long-term care institutions. Canada needs to develop a publicly managed community-based system of primary care to provide integrated care for the frail elderly. The authors describe such a model, which would have clinical and financial responsibility for the full range of health and social services required by this population. This model would represent a major challenge and change for the existing system. Demonstration projects are needed to evaluate its cost-effectiveness and address issues raised by its introduction. PMID:9347783
Non-condensable gas effects in ROSA/AP600 small-break LOCA experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nakamura, Hideo; Kukita, Yutaka; Shaw, R.A.
1996-06-01
Integral experiments simulating the postulated accidents in the Westinghouse AP600 reactor have been conducted using the ROSA-V Large Scale Test Facility (LSTF). These experiments allowed the N{sub 2} gas for the pressurization of accumulator tanks to enter the primary system after the depletion of the tank water inventory. The gas migrated into the Passive Residual Heat Removal (PRHR) system heat exchanger tubes and into the Core Makeup Tanks (CMTs), and influenced the performance of these components which are unique to the AP600 reactor. Specifically, the PRHR was disabled soon after the N{sub 2} gas discharge in most of the experiments,more » although the core decay power was removed well by the steam discharge through the Automatic Depressurization System (ADS) after the PRHR was disabled. The N{sub 2} gas ingress into the CMTs occurred in the experiments with relatively large breaks ({ge} 2 inch in equivalent diameter), and contributed to a smooth draindown of the CMT inventory into the primary system.« less
Kornuta, Jeffrey A.; Dixon, J. Brandon
2015-01-01
In addition to external forces, collecting lymphatic vessels intrinsically contract to transport lymph from the extremities to the venous circulation. As a result, the lymphatic endothelium is routinely exposed to a wide range of dynamic mechanical forces, primarily fluid shear stress and circumferential stress, which have both been shown to affect lymphatic pumping activity. Although various ex-vivo perfusion systems exist to study this innate pumping activity in response to mechanical stimuli, none are capable of independently controlling the two primary mechanical forces affecting lymphatic contractility: transaxial pressure gradient, ΔP, which governs fluid shear stress; and average transmural pressure, Pavg, which governs circumferential stress. Hence, the authors describe a novel ex-vivo lymphatic perfusion system (ELPS) capable of independently controlling these two outputs using a linear, explicit model predictive control (MPC) algorithm. The ELPS is capable of reproducing arbitrary waveforms within the frequency range observed in the lymphatics in vivo, including a time-varying ΔP with a constant Pavg, time-varying ΔP and Pavg, and a constant ΔP with a time-varying Pavg. In addition, due to its implementation of syringes to actuate the working fluid, a post-hoc method of estimating both the flow rate through the vessel and fluid wall shear stress over multiple, long (5 sec) time windows is also described. PMID:24809724
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dhainaut, J.F.; Devaux, J.Y.; Monsallier, J.F.
1986-07-01
Continuous positive pressure ventilation is associated with a reduction in left ventricular preload and cardiac output, but the mechanisms responsible are controversial. The decrease in left ventricular preload may result exclusively from a decreased systemic venous return due to increased pleural pressure, or from an additional effect such as decreased left ventricular compliance. To determine the mechanisms responsible, we studied the changes in cardiac output induced by continuous positive pressure ventilation in eight patients with the adult respiratory distress syndrome. We measured cardiac output by thermodilution, and biventricular ejection fraction by equilibrium gated blood pool scintigraphy. Biventricular end-diastolic volumes weremore » then calculated by dividing stroke volume by ejection fraction. As positive end-expiratory pressure increased from 0 to 20 cm H/sub 2/O, stroke volume and biventricular end-diastolic volumes fell about 25 percent, and biventricular ejection fraction remained unchanged. At 20 cm H/sub 2/O positive end-expiratory pressure, volume expansion for normalizing cardiac output restored biventricular end-diastolic volumes without markedly changing biventricular end-diastolic transmural pressures. The primary cause of the reduction in left ventricular preload with continuous positive pressure ventilation appears to be a fall in venous return and hence in right ventricular stroke volume, without evidence of change in left ventricular diastolic compliance.« less
Neural Control of the Cardiovascular System in Space
NASA Technical Reports Server (NTRS)
Levine, Benjamin D.; Pawelczyk, James A.; Zuckerman, Julie; Zhang, Rong; Fu, Qi; Iwasaki, Kenichi; Ray, Chet; Blomqvist, C. Gunnar; Lane, Lynda D.; Giller, Cole A.
2003-01-01
During the acute transition from lying supine to standing upright, a large volume of blood suddenly moves from the chest into the legs. To prevent fainting, the blood pressure control system senses this change immediately, and rapidly adjusts flow (by increasing heart rate) and resistance to flow (by constricting the blood vessels) to restore blood pressure and maintain brain blood flow. If this system is inadequate, the brain has a backup plan. Blood vessels in the brain can adjust their diameter to keep blood flow constant. If blood pressure drops, the brain blood vessels dilate; if blood pressure increases, the brain blood vessels constrict. This process, which is called autoregulation, allows the brain to maintain a steady stream of oxygen, even when blood pressure changes. We examined what changes in the blood pressure control system or cerebral autoregulation contribute to the blood pressure control problems seen after spaceflight. We asked: (1) does the adaptation to spaceflight cause an adaptation in the blood pressure control system that impairs the ability of the system to constrict blood vessels on return to Earth?; (2) if such a defect exists, could we pinpoint the neural pathways involved?; and (3) does cerebral autoregulation become abnormal during spaceflight, impairing the body s ability to maintain constant brain blood flow when standing upright on Earth? We stressed the blood pressure control system using lower body negative pressure, upright tilt, handgrip exercise, and cold stimulation of the hand. Standard cardiovascular parameters were measured along with sympathetic nerve activity (the nerve activity causing blood vessels to constrict) and brain blood flow. We confirmed that the primary cardiovascular effect of spaceflight was a postflight reduction in upright stroke volume (the amount of blood the heart pumps per beat). Heart rate increased appropriately for the reduction in stroke volume, thereby showing that changes in heart rate regulation alone cannot be responsible for orthostatic hypotension after spaceflight. All of the astronauts in our study had an increase in sympathetic nerve activity during upright tilting on Earth postflight. This increase was well calibrated for the reduction in stroke volume induced by the upright posture. The results obtained from stimulating the sympathetic nervous system using handgrip exercise or cold stress were also entirely normal during and after spaceflight. No astronaut had reduced cerebral blood flow during upright tilt, and cerebral autoregulation was normal or even enhanced inflight. These experiments show that the cardiovascular adaptation to spaceflight does not lead to a defect in the regulation of blood vessel constriction via sympathetic nerve activity. In addition, cerebral autoregulation is well-maintained. It is possible that despite the increased sympathetic nerve activity, blood vessels did not respond with a greater degree of constriction than occurred preflight, possibly uncovering a limit of vasoconstrictor reserve.
Pressurized fluidized bed reactor
Isaksson, J.
1996-03-19
A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine. 1 fig.
Pressurized fluidized bed reactor
Isaksson, Juhani
1996-01-01
A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gerard, R.; Malekian, C.; Meessen, O.
The Leak Before Break (LBB) concept allows to eliminate from the design basis the double-ended guillotine break of the primary loop piping, provided it can be demonstrated by a fracture mechanics analysis that a through-wall flaw, of a size giving rise to a leakage still well detectable by the plant leak detection systems, remains stable even under accident conditions (including the Safe Shutdown Earthquake (SSE)). This concept was successfully applied to the primary loop piping of several Belgian Pressurized Water Reactor (PWR) units, operated by the Utility Electrabel. One of the main benefits is to permit justification of supports inmore » the primary loop and justification of the integrity of the reactor pressure vessel and internals in case of a Loss Of Coolant Accident (LOCA) in stretch-out conditions. For two of the Belgian PWR units, the LBB approach also made it possible to reduce the number of large hydraulic snubbers installed on the primary coolant pumps. Last but not least, the LBB concept also facilitates the steam generator replacement operations, by eliminating the need for some pipe whip restraints located close to the steam generator. In addition to the U.S. regulatory requirements, the Belgian safety authorities impose additional requirements which are described in details in a separate paper. An novel aspect of the studies performed in Belgium is the way in which residual loads in the primary loop are taken into account. Such loads may result from displacements imposed to close the primary loop in a steam generator replacement operation, especially when it is performed using the {open_quote}two cuts{close_quotes} technique. The influence of such residual loads on the LBB margins is discussed in details and typical results are presented.« less
Ofoedu, John N.; Njoku, Patrick U.; Amadi, Agwu N.; Godswill-Uko, Ezinne U.
2013-01-01
Abstract Background As the case detection rates of hypertension increase in adult Nigerians, achieving target blood pressure (BP) control has become an important management challenge. Objectives To describe medication adherence and BP control amongst adult Nigerians with primary hypertension attending a primary care clinic of a tertiary hospital in a resource-poor environment in Eastern Nigeria. Methods A cross-sectional study was carried out in 140 adult patients with primary hypertension who have been on treatment for at least 6 months at the primary care clinic of Federal Medical Centre, Umuahia. A patient was said to have achieved goal BP control if the BP was < 140 per 90 mmHg. Adherence was assessed in the previous 30 days using a pretested researcher-administered questionnaire on 30 days of self-reported therapy. Adherence was graded using an ordinal scoring system of 0–4; an adherent patient was one who scored 4 points in the previous 30 days. Reasons for non-adherence were documented. Results Adherence to medication and BP control rates were 42.9% and 35.0% respectively. BP control was significantly associated with medication adherence (p = 0.03), antihypertensive medication duration ≥3 years (p = 0.042), and taking ≥ one form of antihypertensive medication (p = 0.04). BP at the recruitment visit was significantly higher than at the end of the study (p = 0.036). The most common reason for non-adherence was forgetfulness (p = 0.046). Conclusions The rate of BP control amongst the study population was low, which may be connected with low medication adherence. This study urges consideration of factors relating to adherence alongside other factors driving goal BP control.
Activating the nuclear piston mechanism of 3D migration in tumor cells
2017-01-01
Primary human fibroblasts have the remarkable ability to use their nucleus like a piston, switching from low- to high-pressure protrusions in response to the surrounding three-dimensional (3D) matrix. Although migrating tumor cells can also change how they migrate in response to the 3D matrix, it is not clear if they can switch between high- and low-pressure protrusions like primary fibroblasts. We report that unlike primary fibroblasts, the nuclear piston is not active in fibrosarcoma cells. Protease inhibition rescued the nuclear piston mechanism in polarized HT1080 and SW684 cells and generated compartmentalized pressure. Achieving compartmentalized pressure required the nucleoskeleton–cytoskeleton linker protein nesprin 3, actomyosin contractility, and integrin-mediated adhesion, consistent with lobopodia-based fibroblast migration. In addition, this activation of the nuclear piston mechanism slowed the 3D movement of HT1080 cells. Together, these data indicate that inhibiting protease activity during polarized tumor cell 3D migration is sufficient to restore the nuclear piston migration mechanism with compartmentalized pressure characteristic of nonmalignant cells. PMID:27998990
Self-actuated shutdown system for a commercial size LMFBR. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dupen, C.F.G.
1978-08-01
A Self-Actuated Shutdown System (SASS) is defined as a reactor shutdown system in which sensors, release mechanisms and neutron absorbers are contained entirely within the reactor core structure, where they respond inherently to abnormal local process conditions, by shutting down the reactor, independently of the plant protection system (PPS). It is argued that a SASS, having a response time similar to that of the PPS, would so reduce the already very low probability of a failure-to-scram event that costly design features, derived from core disruptive accident analysis, could be eliminated. However, the thrust of the report is the feasibility andmore » reliability of the in-core SASS hardware to achieve sufficiently rapid shutdown. A number of transient overpower and transient undercooling-responsive systems were investigated leading to the selection of a primary candidate and a backup concept. During a transient undercooling event, the recommended device is triggered by the associated rate of change of pressure, whereas the alternate concept responds to the reduction in core pressure drop and requires calibration and adjustment by the operators to accommodate changes in reactor power.« less
[Blood pressure lowering therapy for mild hypertensive patients with a history of stroke].
Ishikawa, Eiichi; Ibayashi, Setsuro
2008-08-01
Hypertension is the primary and one of the major risk factors for stroke. Many hypertensive patients with a history of stroke might have mild to moderate hypertension at the same time. In order to prevent recurrence of cardiovascular diseases including stroke, we should lower their blood pressure levels, carefully and slowly below less than 140/90 mmHg or much lower. Additionally, the patients having any occlusion or stenoses in their carotid and/or intracranial arteries, or even in old-old patients with atherosclerosis, might need further consideration for the cerebral blood flow insufficiency in the course of blood pressure lowering therapy. Although the advantages of inhibitors of renin-angiotensin system are lionized these days (advertisement based medicine: ABM), we should never forget to select more favorable antihypertensive drugs for each patient in case by case (individual based medicine: IBM), to get the definite blood pressure lowering effects without worsening any complications. We also need further gathering of many evidences in a net-work-meta-analysis way, on blood pressure lowering therapy in those hypertensive patients with a history of stroke (evidence based medicine: EBM).
Numerical Simulations of Instabilities in Single-Hole Office Elements
NASA Technical Reports Server (NTRS)
Ahuja, Vineet; Hosangadi, Ashvin; Hitt, Matthew A.; Lineberry, David M.
2013-01-01
An orifice element is commonly used in liquid rocket engine test facilities either as a flow metering device, a damper for acoustic resonance or to provide a large reduction in pressure over a very small distance in the piping system. While the orifice as a device is largely effective in stepping down pressure, it is also susceptible to a wake-vortex type instability that generates pressure fluctuations that propagate downstream and interact with other elements of the test facility resulting in structural vibrations. Furthermore in piping systems an unstable feedback loop can exist between the vortex shedding and acoustic perturbations from upstream components resulting in an amplification of the modes convecting downstream. Such was the case in several tests conducted at NASA as well as in the Ariane 5 strap-on P230 engine in a static firing test where pressure oscillations of 0.5% resulted in 5% thrust oscillations. Exacerbating the situation in cryogenic test facilities, is the possibility of the formation of vapor clouds when the pressure in the wake falls below the vapor pressure leading to a cavitation instability that has a lower frequency than the primary wake-vortex instability. The cavitation instability has the potential for high amplitude fluctuations that can cause catastrophic damage in the facility. In this paper high-fidelity multi-phase numerical simulations of an orifice element are used to characterize the different instabilities, understand the dominant instability mechanisms and identify the tonal content of the instabilities.
Steurer-Stey, Claudia; Zoller, Marco; Chmiel Moshinsky, Corinne; Senn, Oliver; Rosemann, Thomas
2010-04-14
Insufficient blood pressure control is a frequent problem despite the existence of effective treatment. Insufficient adherence to self-monitoring as well as to therapy is a common reason. Blood pressure self-measurement at home (Home Blood Pressure Measurement, HBPM) has positive effects on treatment adherence and is helpful in achieving the target blood pressure. Only a few studies have investigated whether adherence to HBPM can be improved through simple measures resulting also in better blood pressure control. Improvement of self-monitoring and improved blood pressure control by using a new colour-coded blood pressure diary. Change in systolic and/or diastolic blood pressure 6 months after using the new colour-coded blood pressure diary.Secondary outcome: Adherence to blood pressure self-measurement (number of measurements/entries). Randomised controlled study. 138 adult patients in primary care with uncontrolled hypertension despite therapy. The control group uses a conventional blood pressure diary; the intervention group uses the new colour-coded blood pressure diary (green, yellow, red according a traffic light system). EXPECTED RESULTS/CONCLUSION: The visual separation and entries in three colour-coded areas reflecting risk (green: blood pressure in the target range
[Implementation of a hypertension protocol in a basic health area as a basis for a medical audit].
Vilaplana Vivancos, R; Tobías Ferrer, J
1994-04-15
To analyse compliance in the application of the Arterial Hypertension procedure and the level of monitoring of our hypertensive patients. To introduce quality control methodology into the Primary Care team's work systems. Observation study of a crossover type. Primary Care. Plaza Cataluña PCC, Manresa (Barcelona). Audit of 100 medical records of hypertensive patients selected by systematic random sampling from a total of 533 hypertensive patients under 70 years old. 43% of the hypertensive patients had their pressure figures adequately monitored (CI 95%: 33.3-52.7) with 4.86 average number of checks per year. Analytic blood controls were performed on 66% and urine controls on 56%. Only 34% of patients had a minimal cardiovascular investigation, while back-of-eye investigation and ECGs were performed on 44% and 49%, respectively. The arterial pressure monitoring level is acceptable. Compliance with the procedure is deficient in most complementary investigations. The periodicity of ECGs should be agreed. It is clear that patients for whom compliance with the procedure is most deficient are those who have fewer arterial pressure recordings as well as those receiving no drugs treatment. New objectives are proposed. Lastly, corrective measures are suggested, with a reassessment after two years.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marchesini, Pierpaolo; Daley, Thomas; Ajo-Franklin, Jonathan
Monitoring of time-varying reservoir properties, such as the state of stress, is a primary goal of geophysical investigations, including for geological sequestration of CO 2, enhanced hydrocarbon recovery (EOR), and other subsurface engineering activities. In this work, we used Continuous Active-Source Seismic Monitoring (CASSM), with cross-well geometry, to measure variation in seismic coda amplitude, as a consequence of effective stress change (in the form of changes in pore fluid pressure). To our knowledge, the presented results are the first in-situ example of such crosswell measurement at reservoir scale and in field conditions. Data compliment the findings of our previous workmore » which investigated the relationship between pore fluid pressure and seismic velocity (velocity-stress sensitivity) using the CASSM system at the same field site (Marchesini et al., 2017, in review). We find that P-wave coda amplitude decreases with decreasing pore pressure (increasing effective stress).« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Faidy, C.
Practical applications of the leak-before break concept are presently limited in French Pressurized Water Reactors (PWR) compared to Fast Breeder Reactors. Neithertheless, different fracture mechanic demonstrations have been done on different primary, auxiliary and secondary PWR piping systems based on similar requirements that the American NUREG 1061 specifications. The consequences of the success in different demonstrations are still in discussion to be included in the global safety assessment of the plants, such as the consequences on in-service inspections, leak detection systems, support optimization,.... A large research and development program, realized in different co-operative agreements, completes the general approach.
Fast-acting sprinkler system design considerations for propellant manufacture
NASA Astrophysics Data System (ADS)
Matthews, A. L.; Crable, J. M.; Kristoff, P. T.
1984-08-01
Fast-acting sprinkler systems for detection and suppression of fires in propellant operations, which require activation in the millisecond range in order to be effective, can be easily defeated unless particular attention is paid to design and maintenance details. Of primary consideration are detector selection and placement in processes to minimize the effect of environmental influences. Also important are nozzle placement, water flow density, water supply pressure, and pattern and sloping of piping. When all of these design criteria are properly implemented, water application can occur within 100 ms of fire detection.
Volume accumulator design analysis computer codes
NASA Technical Reports Server (NTRS)
Whitaker, W. D.; Shimazaki, T. T.
1973-01-01
The computer codes, VANEP and VANES, were written and used to aid in the design and performance calculation of the volume accumulator units (VAU) for the 5-kwe reactor thermoelectric system. VANEP computes the VAU design which meets the primary coolant loop VAU volume and pressure performance requirements. VANES computes the performance of the VAU design, determined from the VANEP code, at the conditions of the secondary coolant loop. The codes can also compute the performance characteristics of the VAU's under conditions of possible modes of failure which still permit continued system operation.
Mora, Leticia; Hayes, Maria
2015-02-11
The primary function of dietary protein is to provide amino acids for protein synthesis. However, protein is also a source of latent bioactive peptides or cryptides with potential health benefits including the control and regulation of blood pressure. Hypertension or high blood pressure is one of the major, controllable risk factors in the development of cardiovascular disease (CVD), and it is also implicated in the development of myocardial infarction, heart failure, and end-stage diabetes. Cryptides can act on various systems of the body including the circulatory, gastrointestinal (GI), nervous, skeletal, and respiratory systems. A number of studies carried out to date have examined the health benefits of food protein isolates and hydrolysates. This review provides an overview of existing blood pressure regulating peptides and products derived from fish and other protein sources and hydrolysates. It discusses the methods used currently to generate and identify cryptides from these sources and their application in food and pharmaceutical products. It also looks at the current market for protein-derived peptides and peptide-containing products, legislation governing their use, and the future development of research in this area.
2007-03-13
KENNEDY SPACE CENTER, FLA. -- A flat bed truck hauls the container with the Experiment Logistics Module Pressurized Section inside away from the Trident wharf. The logistics module is part of the Japanese Experiment Module, known as Kibo. The logistics module is being transported to the Space Station Processing Facility at NASA's Kennedy Space Center. Kibo consists of six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007. Photo credit: NASA/Kim Shiflett
Japanese Experiment Module arrival
2007-03-29
Inside the Space Station Processing Facility, workers monitor progress as a huge crane is used to remove the top of the crate carrying the Experiment Logistics Module Pressurized Section for the Japanese Experiment Module. The logistics module is one of the components of the Japanese Experiment Module or JEM, also known as Kibo, which means "hope" in Japanese. Kibo comprises six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007.
Japanese Experiment Module arrival
2007-03-29
Inside the Space Station Processing Facility, the Experiment Logistics Module Pressurized Section for the Japanese Experiment Module is revealed after the top of the crate is removed. The logistics module is one of the components of the Japanese Experiment Module or JEM, also known as Kibo, which means "hope" in Japanese. Kibo comprises six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007.
Large Advanced Space Systems (LASS) computer-aided design program additions
NASA Technical Reports Server (NTRS)
Farrell, C. E.
1982-01-01
The LSS preliminary and conceptual design requires extensive iteractive analysis because of the effects of structural, thermal, and control intercoupling. A computer aided design program that will permit integrating and interfacing of required large space system (LSS) analyses is discussed. The primary objective of this program is the implementation of modeling techniques and analysis algorithms that permit interactive design and tradeoff studies of LSS concepts. Eight software modules were added to the program. The existing rigid body controls module was modified to include solar pressure effects. The new model generator modules and appendage synthesizer module are integrated (interfaced) to permit interactive definition and generation of LSS concepts. The mass properties module permits interactive specification of discrete masses and their locations. The other modules permit interactive analysis of orbital transfer requirements, antenna primary beam n, and attitude control requirements.
Solar fed DC-DC single ended primary inductance converter for low power applications
NASA Astrophysics Data System (ADS)
Narendranath, K. V.; Viswanath, Y.; Babu, K. Suresh; Arunkumar, G.; Elangovan, D.
2017-11-01
This paper presents 34 to 36 volts. SEPIC converter for solar fed applications. Now days, there has been tremendous increase in the usage of solar energy and this solar energy is most valuable energy source available all around the world. The solar energy system require a Dc-Dc converter in order to modulate and govern the changing output of the panel. In this paper, a system comprising of Single Ended Primary Inductance Converter [SEPIC] integrated with solar panel is proposed. This paper proposes SEPIC power converter design that will secure high performance and cost efficiency while powering up a LAMP load. This power converter designed with low output ripple voltage, higher efficiency and less electrical pressure on the power switching elements. The simulation and prototype hardware results are presented in this paper.
2009-12-01
minimal pressure losses. 15. NUMBER OF PAGES 113 14. SUBJECT TERMS Pulse Detonation Combustors, PDC, Pulse Detonation Engines, PDE , PDE ...Postgraduate School PDC Pulse Detonation Combustor PDE Pulse Detonation Engine RAM Random Access Memory RDT Research, Design and Test RPL...inhibiting the implementation of this advanced propulsion system. The primary advantage offered by pulse detonation engines ( PDEs ) is the high efficiency
ERIC Educational Resources Information Center
Hennessy, Jennifer; Hinchion, Carmel; McNamara, Patricia Mannix
2011-01-01
Teachers of English experience significant pressure in attempting to meet the requirements of the national examination system, while also seeking to uphold their own ideological and philosophical perspectives on the value of poetry. Drawing on a mixed method study into the teaching of poetry at post-primary level in Ireland conducted between 2007…
2004-02-10
KENNEDY SPACE CENTER, FLA. - The Multi-Purpose Logistics Module Raffaello moves away from its stand in the Space Station Processing Facility. Raffaello is the second MPLM built by the Italian Space Agency, serving as a reusable logistics carrier and primary delivery system to resupply and return station cargo requiring a pressurized environment. It is being moved to allow the third MPLM, Donatello, to be brought in for routine testing. Donatello has been stored in the Operations and Checkout Building. This is the first time all three MPLMs are in the SSPF; the other one is the Leonardo. Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-13
KENNEDY SPACE CENTER, FLA. - Overhead cables carry the Multi-Purpose Logistics Module Donatello from the payload canister (lower right) to a work stand in the Space Station Processing Facility. Previously housed in the Operations and Checkout Building, Donatello was brought into the SSPF for routine testing. This is the first time all three MPLMs (Donatello, Raffaello and Leonardo) are in the SSPF. The MPLMs were built by the Italian Space Agency, to serve as reusable logistics carriers and the primary delivery system to resupply and return station cargo requiring a pressurized environment. The third MPLM, Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-10
KENNEDY SPACE CENTER, FLA. - Workers in the Space Station Processing Facility secure the Multi-Purpose Logistics Module Raffaello onto a new work stand. Raffaello is the second MPLM built by the Italian Space Agency, serving as a reusable logistics carrier and primary delivery system to resupply and return station cargo requiring a pressurized environment. It has been moved to allow the third MPLM, Donatello, to be brought in for routine testing. Donatello has been stored in the Operations and Checkout Building. This is the first time all three MPLMs are in the SSPF; the other one is the Leonardo. Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-13
KENNEDY SPACE CENTER, FLA. - Workers on the floor of the Space Station Processing Facility watch as overhead cables carry the Multi-Purpose Logistics Module Donatello to a work stand. Previously housed in the Operations and Checkout Building, Donatello was brought into the SSPF for routine testing. This is the first time all three MPLMs (Donatello, Raffaello and Leonardo) are in the SSPF. The MPLMs were built by the Italian Space Agency, to serve as reusable logistics carriers and the primary delivery system to resupply and return station cargo requiring a pressurized environment. The third MPLM, Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
Musaeva, Z A; Oknin, V Iu; Khapaev, B A; Fedotova, A V; Veĭn, A M
2002-01-01
A comparative analysis of parameters of systemic BP in patients with primary arterial hypotension (PAH) and in patients with neurogenic syncopes (NS) in the cycle sleep-awake. Blood pressure was investigated in 20 patients with PAH aged 16-44 years and 18 patients with NS aged 16-49 years. 24-h ambulatory monitoring of BP was made on the monitor ABPM-02/M (Meditech, Hungary). Rhythm indices of BP in NS patients corresponded to age normal criteria. 24-h arrhythmia of BP in PAH patients manifests with excessive drop of diastolic BP in sleep (55% patients were overdippers). PAH and NS patients differ maximally by hypotonic load in sleep: 1.0 +/- 0.7% in NS vs 15.4 +/- 3.2% in PAH. Hypotonia episodes in awake PAH patients were registered at each 4th-5th measurement of BP, in NS patients--at each 11th-13th. Heart rate in awake PAH patients is higher than in healthy subjects. Hypotonic load in sleep carries the highest differentially-diagnostic importance. This makes more perspective examinations of such patients in the cycle sleep-awake. The changes observed in PAH patients evidence for activation of cerebral sympathico-adrenal systems participating in baroreflex regulation.
Worthley, Stephen G; Wilkins, Gerard T; Webster, Mark W; Montarello, Joseph K; Delacroix, Sinny; Whitbourn, Robert J; Warren, Roderic J
2017-07-01
Catheter-based renal denervation for the treatment of drug-resistant hypertension has been intensively investigated in recent years. To date, only limited data have been published using multi-electrode radiofrequency ablation systems that can deliver lesions with a pre-determined pattern. This study was designed to evaluate the safety and performance of the second generation EnligHTN™ Renal Denervation System. This first-in-human, prospective, multi-center, non-randomized study included 39 patients (62% male, mean age 63 years, and mean baseline office blood pressure 174/93 mmHg) with drug-resistant hypertension. The primary safety and performance objectives were to characterize, from baseline to 6 months post procedure, the rate of serious procedural and device related adverse events, as adjudicated by an independent Clinical Events Committee, and the reduction of office systolic blood pressure. Renal artery denervation, using the second generation EnligHTN multi-electrode system significantly reduced office blood pressure from baseline to 1, 3, 6, 12, 18 and 24 months by 19/7, 26/9, 25/7, 23/7, 25/8 and 27/9 mmHg, respectively (p ≤ 0.0005). No serious device or procedure related adverse events affecting the renal arteries or renal function occurred through 24 months of follow-up. Renal sympathetic denervation using the second generation EnligHTN Renal Denervation System resulted in safe, rapid, and significant mean office blood pressure reduction that was sustained through 24 months. Future studies will need to address the utility of this system against an appropriate sham based comparator. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
Low-Cost High-Pressure Hydrogen Generator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cropley, Cecelia C.; Norman, Timothy J.
Electrolysis of water, particularly in conjunction with renewable energy sources, is potentially a cost-effective and environmentally friendly method of producing hydrogen at dispersed forecourt sites, such as automotive fueling stations. The primary feedstock for an electrolyzer is electricity, which could be produced by renewable sources such as wind or solar that do not produce carbon dioxide or other greenhouse gas emissions. However, state-of-the-art electrolyzer systems are not economically competitive for forecourt hydrogen production due to their high capital and operating costs, particularly the cost of the electricity used by the electrolyzer stack. In this project, Giner Electrochemical Systems, LLC (GES)more » developed a low cost, high efficiency proton-exchange membrane (PEM) electrolysis system for hydrogen production at moderate pressure (300 to 400 psig). The electrolyzer stack operates at differential pressure, with hydrogen produced at moderate pressure while oxygen is evolved at near-atmospheric pressure, reducing the cost of the water feed and oxygen handling subsystems. The project included basic research on catalysts and membranes to improve the efficiency of the electrolysis reaction as well as development of advanced materials and component fabrication methods to reduce the capital cost of the electrolyzer stack and system. The project culminated in delivery of a prototype electrolyzer module to the National Renewable Energy Laboratory for testing at the National Wind Technology Center. Electrolysis cell efficiency of 72% (based on the lower heating value of hydrogen) was demonstrated using an advanced high-strength membrane developed in this project. This membrane would enable the electrolyzer system to exceed the DOE 2012 efficiency target of 69%. GES significantly reduced the capital cost of a PEM electrolyzer stack through development of low cost components and fabrication methods, including a 60% reduction in stack parts count. Economic analysis indicates that hydrogen could be produced for $3.79 per gge at an electricity cost of $0.05/kWh by the lower-cost PEM electrolyzer developed in this project, assuming high-volume production of large-scale electrolyzer systems.« less
Japanese Experiment Module (JEM)
NASA Technical Reports Server (NTRS)
2003-01-01
The Japanese Experiment Module (JEM) pressure module is removed from its shipping crate and moved across the floor of the Space Station Processing Facility at Kennedy Space Center (KSC) to a work stand. A research laboratory, the pressurized module is the first element of the JEM, named 'Kibo' (Hope) to arrive at KSC. Japan's primary contribution to the International Space Station, the module will enhance unique research capabilities of the orbiting complex by providing an additional environment in which astronauts will conduct experiments. The JEM also includes an exposed facility or platform for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.
Asayut, Narong; Sookaneknun, Phayom; Chaiyasong, Surasak; Saramunee, Kritsanee
2018-02-01
Identify costs, outcomes and stakeholders' perspectives associated with incorporation of community pharmacy services into the Thai National Health Insurance System and their values to all stakeholders. Using a combination of search terms, a comprehensive literature search was performed using the Thai Journal Citation Index Centre, Health System Research Institute database, PubMed and references from recent reviews. Identified studies were published between January 2000 and December 2014. The review included publications in English and Thai on primary research undertaken in community pharmacies associated with the National Health Insurance System. Two independent authors performed study selection, data extraction and quality assessment. The literature search yielded 251 titles, with 18 satisfying the inclusion criteria. Clinical outcomes of community pharmacy services included control and reduction in blood pressure and blood sugar, improved adherence to medications, an increase in acceptance of interventions, and an increase in healthy behaviours. Thirty-three percentage of those at risk of diabetes and hypertension achieved normal blood sugar and blood pressure levels after being followed for 2-6 months by a community pharmacist. The cost of collaborative screening by community pharmacies and primary care units was US$ 4.5. Diabetes management costs were US$ 5.1-30.7. Community pharmacists reported high satisfaction rates. Stakeholders' perspectives revealed support for the community pharmacists' roles and the inclusion of community pharmacies as partners with the National Health Insurance System. Community pharmacy services improved outcomes for diabetic and hypertensive patients. This review supports the feasibility of incorporating community pharmacies into the Thai National Health System. © 2017 Royal Pharmaceutical Society.
NASA Astrophysics Data System (ADS)
Legras, Jean-Claude; Jousten, Karl; Severn, Ian
2005-12-01
The fourth CCM (Consultative Committee for Mass and related quantities) International Conference on Pressure Metrology from Ultra-High Vacuum to Very High Pressures (10-9 Pa to 109 Pa) was held at the Institute of Physics in London from 19-21 April 2005. The event, which was organized by the Low, Medium and High Pressure working groups of the CCM, was attended by in excess of one hundred participants with representatives from five continents and every regional metrology organization. The purpose of this conference is to review all the work that is devoted to the highest quality of pressure measurement by primary standards as well as the dissemination of the pressure scale. A total of 52 papers were presented orally, and 26 as posters, in sessions that covered the following topics: Latest scientific advances in pressure and vacuum metrology Innovative transfer standards, advanced sensors and new instrument development Primary (top-level) measurement standards International and regional key comparisons New approaches to calibration It is interesting the note that since the third conference in 1999 the pressure range covered has increased by two orders of magnitude to 109 Pa, to take into account more exacting scientific and industrial demands for traceable vacuum measurement. A further feature of the conference was the increased range of instrumentation and techniques used in the realization and potential realization of pressure standards. Seton Bennett, Director of International Metrology at the National Physical Laboratory, opened the conference and Andrew Wallard, Director of the Bureau International des Poids et Mesures (BIPM), gave the keynote address which described the implementation of the mutual recognition arrangement and the resulting removal of metrological barriers to international trade. Many experts have contributed significant amounts of their time to organize the event and to review the submitted papers. Thanks are due to all of these people, particularly Gianfranco Molinar who offered much advice based on experience of organizing the previous conference. Special thanks must also be made to Mitsuru Tanaka, President of the CCM, and Andrew Wallard, Director of the BIPM, for their support of the event. The event was coordinated by Jasmina Bolfek-Radovani, of the Institute of Physics, without whose tireless efforts the event would not have been as successful. The production of this issue of Metrologia would not have been possible without the help and support of its editor, Jeffrey Williams. The National Measurement System Directorate of the Department of Trade and Industry supported the conference and it was sponsored by DH Instruments and BOC Edwards. Additional financial assistance was also received from Chell Instruments Ltd, DH-Budenberg, GE Infrastructure Sensing, Hi-Pro Pressure Products Ltd, Kurt J Lesker Company Ltd and Leybold Vacuum UK Ltd. Finally we would like to thank all of the conference participants who made the event both technically stimulating and enjoyable. By the time the next CCM Pressure conference is held in Berlin in 2011, pressure science and technology will undoubtedly have moved on still further and we may see the culmination of work to realize primary pressure standards by more fundamental methods.
ERIC Educational Resources Information Center
Taylor, Neil; Lucas, Keith B.
2000-01-01
Describes a teaching sequence on gaseous pressure implemented in a group of pre-service primary teachers in Fiji that provides subjects with a strong visual model of particle behavior which they then applied to a series of collaborative science activities for which they attempted to construct explanations. Suggests that this teaching sequence…
Kamamoto, Fabio; Lima, Ana Lucia Munhoz; Rezende, Marcelo Rosa de; Mattar-Junior, Rames; Leonhardt, Marcos de Camargo; Kojima, Kodi Edson; Santos, Carla Chineze Dos
2017-12-01
Negative-pressure wound therapy has been widely adopted to reduce the complexity of treating a broad range of acute and chronic wounds. However, its cost is high. The objective of this study was to evaluate the following two different methods of negative-pressure wound therapy in terms of healing time: a low-cost method of negative-pressure wound therapy (a pressure stabilizer device connected to a hospital wall-vacuum system with a gauze-sealed dressing, USP) and the standard of care (vacuum-assisted closure, VAC). This is a randomized, controlled, non-inferiority, unblinded trial. Patients admitted with complex injuries to a trauma center in a public referral hospital who were indicated for orthopedic surgery were randomized to a USP or VAC group. The primary outcome was the time required to achieve a "ready for surgery condition", which was defined as a wound bed with healthy granulation tissue and without necrosis or purulent secretion. Wound bed area contraction, granulation tissue growth and the direct costs of the dressings were secondary outcomes. Variation in area and granulation tissue growth were essentially the same between the systems, and healing time was equal between the groups (p=0.379). In both systems, serial debridement increased wound area (p=0.934), and granulation tissue was also increased (p=0.408). The mean treatment cost was US$ 15.15 in the USP group and US$ 872.59 in the VAC group. For treating complex traumatic injuries, USP was non-inferior to and less expensive than VAC.
[Evaluation of the quality of medical care in primary care patients with metabolic syndrome].
Modrego Navarro, Angel; Ramírez Espinosa, Manuel; Fustero Fernández, Mariví; Tarraga López, Pedro Juan; Bastida Calvo, José Carlos; Torras Tohà, Núria
2009-08-01
As there is a high prevalence of metabolic syndrome (MS) in the overweight population, their cardiovascular risk is also high and the review system in Spain appears to be inadequate. The present study was carried out to evaluate the quality of the medical care of these patients. Epidemiological, cross-sectional and multicenter study. A total of 138 primary care general practitioners from all over Spain included outpatients of both sexes, > 18 years old, with body mass index > or = 25 and with biochemical data from the last 6 months for fasting glucose, triglycerides, HDL-c and blood pressure. Self-evaluation, retrospective, internal and with data processing. Principal determinations: Degree of compliance of 12 evaluation criteria and description of MS factors. A total of 2,280 patients were analysed. MS prevalence was 53.2%. Biochemical data were significantly higher in patients with MS and the most prevalent risk factors were: triglycerides > 150 (49.6%), systolic blood pressure > 140 (40.8%), fasting glucose > or = 126 (38.4%). Poor compliance of a few but relevant criteria was responsible for a high percentage of errors in the medical care quality. Introduction of improvement activities in patients with MS in primary care is essential in the management and prevention of cardiovascular complications.
Genetic Heterogeneity in Therapy-Naïve Synchronous Primary Breast Cancers and Their Metastases.
Ng, Charlotte K Y; Bidard, Francois-Clement; Piscuoglio, Salvatore; Geyer, Felipe C; Lim, Raymond S; de Bruijn, Ino; Shen, Ronglai; Pareja, Fresia; Berman, Samuel H; Wang, Lu; Pierga, Jean-Yves; Vincent-Salomon, Anne; Viale, Agnes; Norton, Larry; Sigal, Brigitte; Weigelt, Britta; Cottu, Paul; Reis-Filho, Jorge S
2017-08-01
Purpose: Paired primary breast cancers and metachronous metastases after adjuvant treatment are reported to differ in their clonal composition and genetic alterations, but it is unclear whether these differences stem from the selective pressures of the metastatic process, the systemic therapies, or both. We sought to define the repertoire of genetic alterations in breast cancer patients with de novo metastatic disease who had not received local or systemic therapy. Experimental Design: Up to two anatomically distinct core biopsies of primary breast cancers and synchronous distant metastases from nine patients who presented with metastatic disease were subjected to high-depth whole-exome sequencing. Mutations, copy number alterations and their cancer cell fractions, and mutation signatures were defined using state-of-the-art bioinformatics methods. All mutations identified were validated with orthogonal methods. Results: Genomic differences were observed between primary and metastatic deposits, with a median of 60% (range 6%-95%) of shared somatic mutations. Although mutations in known driver genes including TP53, PIK3CA , and GATA3 were preferentially clonal in both sites, primary breast cancers and their synchronous metastases displayed spatial intratumor heterogeneity. Likely pathogenic mutations affecting epithelial-to-mesenchymal transition-related genes, including SMAD4, TCF7L2 , and TCF4 ( ITF2 ), were found to be restricted to or enriched in the metastatic lesions. Mutational signatures of trunk mutations differed from those of mutations enriched in the primary tumor or the metastasis in six cases. Conclusions: Synchronous primary breast cancers and metastases differ in their repertoire of somatic genetic alterations even in the absence of systemic therapy. Mutational signature shifts might contribute to spatial intratumor genetic heterogeneity. Clin Cancer Res; 23(15); 4402-15. ©2017 AACR . ©2017 American Association for Cancer Research.
NASA Technical Reports Server (NTRS)
Edwards, Darryl; Ungar, Eugene K.; Holt, James M.
2002-01-01
The International Space Station (ISS) employs an Internal Active Thermal Control System (IATCS) comprised of several single-phase water coolant loops. These coolant loops are distributed throughout the ISS pressurized elements. The primary element coolant loops (i.e. U.S. Laboratory module) contain a fluid accumulator to accomodate thermal expansion of the system. Other element coolant loops are parasitic (i.e. Airlock), have no accumulator, and require an alternative approach to insure that the system maximum design pressure (MDP) is not exceeded during the Launch to Activation (LTA) phase. During this time the element loops is a stand alone closed system. The solution approach for accomodating thermal expansion was affected by interactions of system components and their particular limitations. The mathematical solution approach was challenged by the presence of certain unknown or not readily obtainable physical and thermodynamic characteristics of some system components and processes. The purpose of this paper is to provide a brief description of a few of the solutions that evolved over time, a novel mathematical solution to eliminate some of the unknowns or derive the unknowns experimentally, and the testing and methods undertaken.
NASA Technical Reports Server (NTRS)
Edwards, J. Darryl; Ungar, Eugene K.; Holt, James M.; Turner, Larry D. (Technical Monitor)
2001-01-01
The International Space Station (ISS) employs an Internal Active Thermal Control System (IATCS) comprised of several single-phase water coolant loops. These coolant loops are distributed throughout the ISS pressurized elements. The primary element coolant loops (i.e., US Laboratory module) contain a fluid accumulator to accommodate thermal expansion of the system. Other element coolant loops are parasitic (i.e., Airlock), have no accumulator, and require an alternative approach to insure that the system Maximum Design Pressure (MDP) is not exceeded during the Launch to Activation phase. During this time the element loop is a stand alone closed individual system. The solution approach for accommodating thermal expansion was affected by interactions of system components and their particular limitations. The mathematical solution approach was challenged by the presence of certain unknown or not readily obtainable physical and thermodynamic characteristics of some system components and processes. The purpose of this paper is to provide a brief description of a few of the solutions that evolved over time, a novel mathematical solution to eliminate some of the unknowns or derive the unknowns experimentally, and the testing and methods undertaken.
Plasma Cell Depletion Attenuates Hypertension in an Experimental Model of Autoimmune Disease.
Taylor, Erin B; Barati, Michelle T; Powell, David W; Turbeville, Hannah R; Ryan, Michael J
2018-04-01
Numerous studies show a direct relation between circulating autoantibodies, characteristic of systemic autoimmune disorders, and primary hypertension in humans. Whether these autoantibodies mechanistically contribute to the development of hypertension remains unclear. Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder characterized by aberrant immunoglobulin production, notably pathogenic autoantibodies, and is associated with prevalent hypertension, renal injury, and cardiovascular disease. Because plasma cells produce the majority of serum immunoglobulins and are the primary source of autoantibodies in SLE, we hypothesized that plasma cell depletion using the proteasome inhibitor bortezomib would lower autoantibody production and attenuate hypertension. Thirty-week-old female SLE (NZBWF1) and control (NZW [New Zealand White]) mice were injected IV with vehicle (0.9% saline) or bortezomib (0.75 mg/kg) twice weekly for 4 weeks. Bortezomib treatment significantly lowered the percentage of bone marrow plasma cells in SLE mice. Total plasma IgG and anti-dsDNA IgG levels were higher in SLE mice compared with control mice but were lowered by bortezomib treatment. Mean arterial pressure (mm Hg) measured in conscious mice by carotid artery catheter was higher in SLE mice than in control mice, but mean arterial pressure was significantly lower in bortezomib-treated SLE mice. Bortezomib also attenuated renal injury, as assessed by albuminuria and glomerulosclerosis, and reduced glomerular immunoglobulin deposition and B and T lymphocytes infiltration into the kidneys. Taken together, these data show that the production of autoantibodies by plasma cells mechanistically contributes to autoimmune-associated hypertension and suggests a potential role for patients with primary hypertension who have increased circulating immunoglobulins. © 2018 American Heart Association, Inc.
Design of MSR primary circuit with minimum pressure losses
NASA Astrophysics Data System (ADS)
Noga, Tomáš; Žitek, Pavel; Valenta, Václav
This article describes a design of a MSR primary circuit with minimum pressure losses. It includes a brief description of this type of a reactor and its integral layout, properties, purpose, etc. The objective of this paper is to define problems of pressure losses calculation and to design a proper device for a primary circuit of MSR reactor, including its basic dimensions. Thanks to this, it can become an initial project for a construction of a real piece of work. This is the main contribution of the carried out study. Of course, this article is not a detailed solution, but it points out facts and problems, which future designers may have to face. The further step of our work will be a reconstruction of the current experiment for a two-stage flowing.
NASA Astrophysics Data System (ADS)
Raeesi, Behrooz; Piri, Mohammad
2009-10-01
SummaryWe use a three-dimensional mixed-wet random pore-scale network model to investigate the impact of wettability and trapping on the relationship between interfacial area, capillary pressure and saturation in two-phase drainage and imbibition processes. The model is a three-dimensional network of interconnected pores and throats of various geometrical shapes. It allows multiple phases to be present in each capillary element in wetting and spreading layers, as well as occupying the center of the pore space. Two different random networks that represent the pore space in Berea and a Saudi Arabia reservoir sandstone are used in this study. We allow the wettability of the rock surfaces contacted by oil to alter after primary drainage. The model takes into account both contact angle and trapping hystereses. We model primary oil drainage and water flooding for mixed-wet conditions, and secondary oil injection for a water-wet system. The total interfacial area for pores and throats are calculated when the system is at capillary equilibrium. They include contributions from the arc menisci (AMs) between the bulk and corner fluids, and from the main terminal menisci (MTMs) between different bulk fluids. We investigate hysteresis in these relationships by performing water injection into systems of varying wettability and initial water saturation. We show that trapping and contact angle hystereses significantly affect the interfacial area. In a strongly water-wet system, a sharp increase is observed at the beginning of water flood, which shifts the area to a higher level than primary drainage. As we change the wettability of the system from strongly water-wet to strongly oil-wet, the trapped oil saturation decreases significantly. Starting water flood from intermediate water saturations, greater than the irreducible water saturation, can also affect the non-wetting phase entrapment, resulting in different interfacial area behaviors. This can increase the interfacial area significantly in oil-wet systems. A qualitative comparison of our results with the experimental data available in literature for glass beads shows, with some expected differences, an encouraging agreement. Also, our results agree well with those generated by the previously developed models.
Changing roles for primary-care physicians: addressing challenges and opportunities.
McLaughlin, C P; Kaluzny, A D; Kibbe, D C; Tredway, R
2005-01-01
Direct-to-consumer advertising is but one example of a process called disintermediation that is directly affecting primary-care physicians and their patients. This paper examines the trends and the actors involved in disintermediation, which threatens the traditional patient-physician relationship. The paper outlines the social forces behind these threats and illustrates the resulting challenges and opportunities. A rationale and strategies are presented to rebuild, maintain and strengthen the patient-physician relationship in an era of growing disintermediation and anticipated advancements in cost-effective office-based information systems. Primary care--as we know it--is under siege from a number of trends in healthcare delivery, resulting in loss of physician autonomy, disrupted continuity of care and potential erosion of professional values (Rastegar 2004; Future of Family Medicine Project Leadership Committee 2004). The halcyon days of medicine as a craft guild with a monopoly on (1) technical knowledge and (2) the means of implementation, reached its zenith in the mid-twentieth century and has been under pressure ever since (Starr 1982; Schlesinger 2002). While this is a trend within the US health system, it is likely to affect other delivery systems in the years ahead.
2013-01-01
Background Medical treatment of hypertension is not always sufficient to achieve blood pressure control. Despite this, previous studies on supplementary therapies, such as yoga, are relatively few. We investigated the effects of two yoga interventions on blood pressure and quality of life in patients in primary health care diagnosed with hypertension. Methods Adult patients (age 20–80 years) with diagnosed hypertension were identified by an electronic chart search at a primary health care center in southern Sweden. In total, 83 subjects with blood pressure values of 120–179/≤109 mmHg at baseline were enrolled. At baseline, the patients underwent standardized blood pressure measurement at the health care center and they completed a questionnaire on self-rated quality of life (WHOQOL-BREF). There were three groups: 1) yoga class with yoga instructor (n = 28); 2) yoga at home (n = 28); and 3) a control group (n = 27). The participants were matched at the group level for systolic blood pressure. After 12 weeks of intervention, the assessments were performed again. At baseline a majority of the patients (92%) were on antihypertensive medication, and the patients were requested not to change their medication during the study. Results The yoga class group showed no improvement in blood pressure or self-rated quality of life, while in the yoga at home group there was a decline in diastolic blood pressure of 4.4 mmHg (p < 0.05) compared to the control group. Moreover, the yoga at home group showed significant improvement in self-rated quality of life compared to the control group (p < 0.05). Conclusions A short yoga program for the patient to practice at home seems to have an antihypertensive effect, as well as a positive effect on self-rated quality of life compared to controls. This implies that simple yoga exercises may be useful as a supplementary blood pressure therapy in addition to medical treatment when prescribed by primary care physicians. Trial registration ClinicalTrials.gov (NCT01302535) PMID:24314119
Hanley, Janet; Wild, Sarah; Pagliari, Claudia; Paterson, Mary; Lewis, Steff; Sheikh, Aziz; Krishan, Ashma; Stoddart, Andrew; Padfield, Paul
2013-01-01
Objective To determine if an intervention consisting of telemonitoring and supervision by usual primary care clinicians of home self measured blood pressure and optional patient decision support leads to clinically important reductions in daytime systolic and diastolic ambulatory blood pressure in patients with uncontrolled blood pressure. Design Multicentre randomised controlled trial. Setting 20 primary care practices in south east Scotland. Participants 401 people aged 29-95 years with uncontrolled blood pressure (mean daytime ambulatory measurement ≥135/85 mm Hg but ≤210/135 mm Hg). Intervention Self measurement and transmission of blood pressure readings to a secure website for review by the attending nurse or doctor and participant, with optional automated patient decision support by text or email for six months. Main outcome measures Blinded assessment of mean daytime systolic ambulatory blood pressure six months after randomisation. Results 200 participants were randomised to the intervention and 201 to usual care; primary outcome data were available for 90% of participants (182 and 177, respectively). The mean difference in daytime systolic ambulatory blood pressure adjusted for baseline and minimisation factors between intervention and usual care was 4.3 mm Hg (95% confidence interval 2.0 to 6.5; P=0.0002) and for daytime diastolic ambulatory blood pressure was 2.3 mm Hg (0.9 to 3.6; P=0.001), with higher values in the usual care group. The intervention was associated with a mean increase of one general practitioner (95% confidence interval 0.5 to 1.6; P=0.0002) and 0.6 (0.1 to 1.0; P=0.01) practice nurse consultations during the course of the study. Conclusions Supported self monitoring by telemonitoring is an effective method for achieving clinically important reductions in blood pressure in patients with uncontrolled hypertension in primary care settings. However, it was associated with increase in use of National Health Service resources. Further research is required to determine if the reduction in blood pressure is maintained in the longer term and if the intervention is cost effective. Trial registration Current Controlled Trials ISRCTN72614272. PMID:23709583
Purdy, Phillip D; South, Charles; Klucznik, Richard P; Liu, Kenneth C; Novakovic, Robin L; Puri, Ajit S; Pride, G Lee; Aagaard-Kienitz, Beverly; Ray, Abishek; Elliott, Alan C
2017-08-01
Monitoring of blood pressure (BP) during procedures is variable, depending on multiple factors. Common methods include sphygmomanometer (BP cuff), separate radial artery catheterization, and side port monitoring of an indwelling sheath. Each means of monitoring has disadvantages, including time consumption, added risk, and signal dampening due to multiple factors. We sought an alternative approach to monitoring during procedures in the catheterization laboratory. A new technology involving a 330 µm fiberoptic sensor embedded in the wall of a sheath structure was tested against both radial artery catheter and sphygmomanometer readings obtained simultaneous with readings recorded from the pressure sensing system (PSS). Correlations and Bland-Altman analysis were used to determine whether use of the PSS could substitute for these standard techniques. The results indicated highly significant correlations in systolic, diastolic, and mean arterial pressures (MAP) when compared against radial artery catheterization (p<0.0001), and MAP means differed by <4%. Bland-Altman analysis of the data suggested that the sheath measurements can replace a separate radial artery catheter. While less striking, significant correlations were seen when PSS readings were compared against BP cuff readings. The PSS has competitive functionality to that seen with a dedicated radial artery catheter for BP monitoring and is available immediately on sheath insertion without the added risk of radial catheterization. The sensor is structurally separated from the primary sheath lumen and readings are unaffected by device introduction through the primary lumen. Time delays and potential complications from radial artery catheterization are avoided. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Engineering a Successful Mission: Lessons from the Lunar Reconnaissance Orbiter
NASA Technical Reports Server (NTRS)
Everett, David F.
2011-01-01
Schedule pressure is common in the commercial world, where late delivery of a product means delayed income and loss of profit. 12 Research spacecraft developed by NASA, on the other hand, tend to be driven by the high cost of launch vehicles and the public scrutiny of failure-- the primary driver is ensuring proper operation in space for a system that cannot be retrieved for repair. The Lunar Reconnaissance Orbiter (LRO) development faced both schedule pressure and high visibility. The team had to balance the strong push to meet a launch date against the need to ensure that this first mission for Exploration succeeded. This paper will provide an overview of the mission from concept through its first year of operation and explore some of the challenges the systems engineering team faced taking a mission from preliminary design review to pre-ship review in 3 years.
Lunar Architecture Team - Phase 2 Habitat Volume Estimation: "Caution When Using Analogs"
NASA Technical Reports Server (NTRS)
Rudisill, Marianne; Howard, Robert; Griffin, Brand; Green, Jennifer; Toups, Larry; Kennedy, Kriss
2008-01-01
The lunar surface habitat will serve as the astronauts' home on the moon, providing a pressurized facility for all crew living functions and serving as the primary location for a number of crew work functions. Adequate volume is required for each of these functions in addition to that devoted to housing the habitat systems and crew consumables. The time constraints of the LAT-2 schedule precluded the Habitation Team from conducting a complete "bottoms-up" design of a lunar surface habitation system from which to derive true volumetric requirements. The objective of this analysis was to quickly derive an estimated total pressurized volume and pressurized net habitable volume per crewmember for a lunar surface habitat, using a principled, methodical approach in the absence of a detailed design. Five "heuristic methods" were used: historical spacecraft volumes, human/spacecraft integration standards and design guidance, Earth-based analogs, parametric "sizing" tools, and conceptual point designs. Estimates for total pressurized volume, total habitable volume, and volume per crewmember were derived using these methods. All method were found to provide some basis for volume estimates, but values were highly variable across a wide range, with no obvious convergence of values. Best current assumptions for required crew volume were provided as a range. Results of these analyses and future work are discussed.
High pressure effects on the structural functionality of condensed globular-protein matrices.
Savadkoohi, Sobhan; Kasapis, Stefan
2016-07-01
High pressure technology is the outcome of consumer demand for better quality control of processed foods. There is great potential to apply HPP to condensed systems of globular proteins for the generation of industry-relevant biomaterials with advanced techno- and biofunctionality. To this end, research demonstrates that application of high hydrostatic pressure generates a coherent structure and preserves the native conformation in condensed globular proteins, which is an entirely unexpected but interesting outcome on both scientific and technological grounds. In microbiological challenge tests, high pressure at conventional commercial conditions, demonstrated to effectively reduce the concentration of typical Gram negative or Gram positive foodborne pathogens, and proteolytic enzymes in high-solid protein samples. This may have industrial significance in relation to the formulation and stabilisation of "functional food" products as well as in protein ingredients and concentrates by replacing spray dried powders with condensed HPP-treated pastes that maintain structure and bioactivity. Fundamental concepts and structural functionality of condensed matrices of globular proteins are the primary interest in this mini-review, which may lead to opportunities for industrial exploitation, but earlier work on low-solid systems is also summarised presently to put recent developments in context of this rapidly growing field. Copyright © 2016. Published by Elsevier B.V.
An investigation of air solubility in Jet A fuel at high pressures
NASA Technical Reports Server (NTRS)
Faeth, G. M.
1981-01-01
Problems concerned with the supercritical injection concept are discussed. Supercritical injection involves dissolving air into a fuel prior to injection. A similar effect is obtained by preheating the fuel so that a portion of the fuel flashes when its pressure is reduced. Flashing improves atomization properties and the presence of air in the primary zone of a spray flame reduces the formation of pollutants. The investigation is divided into three phases: (1) measure the solubility and density properties of fuel/gas mixtures, including Jet A/air, at pressures and correlate these results using theory; (2) investigate the atomization properties of flashing liquids, including fuel/dissolved gas systems. Determine and correlate the effect of inlet properties and injector geometry on mass flow rates, Sauter mean diameter and spray angles; (3) examine the combustion properties of flashing injection in an open burner flame, considering flame shape and soot production.
NACA0012 benchmark model experimental flutter results with unsteady pressure distributions
NASA Technical Reports Server (NTRS)
Rivera, Jose A., Jr.; Dansberry, Bryan E.; Bennett, Robert M.; Durham, Michael H.; Silva, Walter A.
1992-01-01
The Structural Dynamics Division at NASA Langley Research Center has started a wind tunnel activity referred to as the Benchmark Models Program. The primary objective of this program is to acquire measured dynamic instability and corresponding pressure data that will be useful for developing and evaluating aeroelastic type computational fluid dynamics codes currently in use or under development. The program is a multi-year activity that will involve testing of several different models to investigate various aeroelastic phenomena. This paper describes results obtained from a second wind tunnel test of the first model in the Benchmark Models Program. This first model consisted of a rigid semispan wing having a rectangular planform and a NACA 0012 airfoil shape which was mounted on a flexible two degree of freedom mount system. Experimental flutter boundaries and corresponding unsteady pressure distribution data acquired over two model chords located at the 60 and 95 percent span stations are presented.
NASA Technical Reports Server (NTRS)
Calleja, John; Tamagno, Jose
1993-01-01
A series of air calibration tests were performed in GASL's HYPULSE facility in order to more accurately determine test section flow conditions for flows simulating total enthalpies in the Mach 13 to 17 range. Present calibration data supplements previous data and includes direct measurement of test section pitot and static pressure, acceleration tube wall pressure and heat transfer, and primary and secondary incident shock velocities. Useful test core diameters along with the corresponding free-stream conditions and usable testing times were determined. For the M13.5 condition, in-stream static pressure surveys showed the temporal and spacial uniformity of this quantity across the useful test core. In addition, finite fringe interferograms taken of the free-stream flow at the test section did not indicate the presence of any 'strong' wave system for any of the conditions investigated.
Pressurized fluidized bed reactor and a method of operating the same
Isaksson, J.
1996-02-20
A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine. 1 fig.
Pressurized fluidized bed reactor and a method of operating the same
Isaksson, Juhani
1996-01-01
A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine.
Aboud, Anas; Mederos-Dahms, Hendrikje; Liebing, Kai; Zittermann, Armin; Schubert, Harald; Murray, Edward; Renner, Andre; Gummert, Jan; Börgermann, Jochen
2015-05-29
Because of its low rate of clinical complications, miniaturized extracorporeal perfusion systems (MEPS) are frequently used in heart centers worldwide. However, many recent studies refer to the higher probability of gaseous microemboli formation by MEPS, caused by subzero pressure values. This is the main reason why various de-airing devices were developed for today's perfusion systems. In the present study, we investigated the potential benefits of a simple one-way-valve connected to a volume replacement reservoir (OVR) for volume and pressure compensation. In an experimental study on 26 pigs, we compared MEPS (n = 13) with MEPS plus OVR (n = 13). Except OVR, perfusion equipment was identical in both groups. Primary endpoints were pressure values in the venous line and the right atrium as well as the number and volume of air bubbles. Secondary endpoints were biochemical parameters of systemic inflammatory response, ischemia, hemodilution and hemolysis. One animal was lost in the MEPS + OVR group. In the MEPS + OVR group no pressure values below -150 mmHg in the venous line and no values under -100 mmHg in right atrium were noticed. On the contrary, nearly 20% of venous pressure values in the MEPS group were below -150 and approximately 10% of right atrial pressure values were below -100 mmHg. Compared with the MEPS group, the bubble counter device showed lower numbers of arterial air bubbles in the MEPS + OVR group (mean ± SD: 13444 ± 5709 vs. 1 ± 2, respectively; p < 0.001). In addition, bubble volume was significantly lower in the MEPS + OVR group than in the MEPS group (mean ± SD: 1522 ± 654 μl vs. 4 ± 6 μl, respectively; p < 0.001). The proinflammatory cytokine interleukin-6 and biochemical indices of cardiac ischemia (creatine kinase, and troponin I) were comparable between both groups. The use of a miniaturized perfusion system with a volume replacement reservoir is able to counteract excessive negative venous line pressures and to reduce the number and volume of arterial air bubbles. This approach may lead to a lower rate of neurological complications.
Kottke, Thomas E; Huebsch, Jacquelyn A; McGinnis, Paul; Nichols, Jolleen M; Parker, Emily D; Tillema, Juliana O; Maciosek, Michael V
2016-01-01
Context: Primary care practice. Objective: To test whether the principles of complex adaptive systems are applicable to implementation of team-based primary care. Design: We used complex adaptive system principles to implement team-based care in a private, five-clinic primary care practice. We compared randomly selected samples of patients with coronary heart disease (CHD) and diabetes before system implementation (March 1, 2009, to February 28, 2010) and after system implementation (December 1, 2011, to March 31, 2013). Main Outcome Measures: Rates of patients meeting the composite goals for CHD (blood pressure < 140/90 mmHg, low-density lipoprotein cholesterol level < 100 mg/dL, tobacco-free, and using aspirin unless contraindicated) and diabetes (CHD goal plus hemoglobin A1c concentration < 8%) before and after the intervention. We also measured provider and patient satisfaction with preventive services. Results: The proportion of patients with CHD who met the composite goal increased from 40.3% to 59.9% (p < 0.0001) because documented aspirin use increased (65.2%–97.5%, p < 0.0001) and attainment of the cholesterol goal increased (77.0%–83.9%, p = 0.0041). The proportion of diabetic patients meeting the composite goal rose from 24.5% to 45.4% (p < 0.0001) because aspirin use increased (58.6%–97.6%, p < 0.0001). Increased percentages of patients meeting the CHD and diabetes composite goals were not significantly different (p = 0.2319). Provider satisfaction with preventive services delivery increased significantly (p = 0.0017). Patient satisfaction improved but not significantly. Conclusion: Principles of complex adaptive systems can be used to implement team-based care systems for patients with CHD and possibly diabetic patients. PMID:26784851
Kottke, Thomas E; Huebsch, Jacquelyn A; Mcginnis, Paul; Nichols, Jolleen M; Parker, Emily D; Tillema, Juliana O; Maciosek, Michael V
2016-01-01
Primary care practice. To test whether the principles of complex adaptive systems are applicable to implementation of team-based primary care. We used complex adaptive system principles to implement team-based care in a private, five-clinic primary care practice. We compared randomly selected samples of patients with coronary heart disease (CHD) and diabetes before system implementation (March 1, 2009, to February 28, 2010) and after system implementation (December 1, 2011, to March 31, 2013). Rates of patients meeting the composite goals for CHD (blood pressure < 140/90 mmHg, low-density lipoprotein cholesterol level < 100 mg/dL, tobacco-free, and using aspirin unless contraindicated) and diabetes (CHD goal plus hemoglobin A1c concentration < 8%) before and after the intervention. We also measured provider and patient satisfaction with preventive services. The proportion of patients with CHD who met the composite goal increased from 40.3% to 59.9% (p < 0.0001) because documented aspirin use increased (65.2%-97.5%, p < 0.0001) and attainment of the cholesterol goal increased (77.0%-83.9%, p = 0.0041). The proportion of diabetic patients meeting the composite goal rose from 24.5% to 45.4% (p < 0.0001) because aspirin use increased (58.6%-97.6%, p < 0.0001). Increased percentages of patients meeting the CHD and diabetes composite goals were not significantly different (p = 0.2319). Provider satisfaction with preventive services delivery increased significantly (p = 0.0017). Patient satisfaction improved but not significantly. Principles of complex adaptive systems can be used to implement team-based care systems for patients with CHD and possibly diabetic patients.
Common skin problems in the community and primary care.
Armstrong, Kirsty
2014-10-01
Skin problems can be hard to diagnose, leaving clinicians frustrated and patients incorrectly treated, but rashes and lesions can be markers of systemic disease and infections. However, by using simple history-taking and mnemonics, safety and correct diagnoses can be achieved. This article will consider some common problems encountered in primary and community care, issues that need to be excluded, resources that will help with diagnosis and some management guidelines. This is not an exhaustive guide, and advice should be sought from learned colleagues in specific cases. Pressure area care and the use of compression bandaging will not be discussed unless it is of relevance to the subject of rashes and lesions.
NASA Astrophysics Data System (ADS)
Rieger, Samantha M.
Natural and artificial satellites are subject to perturbations when orbiting near-Earth asteroids. These perturbations include non-uniform gravity from the asteroid, third-body disturbances from the Sun, and solar radiation pressure. For small natural (1 cm-15 m) and artificial satellites, solar radiation pressure is the primary perturbation that will cause their orbits to go unstable. For the asteroid Bennu, the future target of the spacecraft OSIRIS-REx, the possibility of natural satellites having stable orbits around the asteroid and characterize these stable regions is investigated. It has been found that the main orbital phenomena responsible for the stability or instability of these possible natural satellites are Sun-synchronous orbits, the modified Laplace plane, and the Kozai resonance. These findings are applied to other asteroids as well as to artificial satellites. The re-emission of solar radiation pressure through BYORP is also investigated for binary asteroid systems. Specifically, the BYORP force is combined with the Laplace plane such that BYORP expands the orbit of the binary system along the Laplace surface where the secondary increases in inclination. For obliquities from 68.875° - 111.125° the binary will eventually extend into the Laplace instability region, where the eccentricity of the orbit will increase. A subset of the instability region leads to eccentricities high enough that the secondary will impact the primary. This result inspired the development of a hypothesis of a contact-binary binary cycle described briefly in the following. YORP will increase the spin rate of a contact binary while also driving the spin-pole to an obliquity of 90°. Eventually, the contact binary will fission. The binary will subsequently become double-synchronous, thus allowing the BYORP acceleration to have secular effects on the orbit. The orbit will then expand along the Laplace surface to the Laplace plane instability region eventually leading to an impact and the start of a new cycle with the YORP process.
Investigation of VEGGIE Root Mat
NASA Technical Reports Server (NTRS)
Subbiah, Arun M.
2013-01-01
VEGGIE is a plant growth facility that utilizes the phenomenon of capillary action as its primary watering system. A cloth made of Meta Aramid fiber, known as Nomex is used to wick water up from a reservoir to the bottom of the plants roots. This root mat system is intended to be low maintenance with no moving parts and requires minimal crew interface time. Unfortunately, the water wicking rates are inconsistent throughout the plant life cycle, thus causing plants to die. Over-wicking of water occurs toward the beginning of the cycle, while under-wicking occurs toward the middle. This inconsistency of wicking has become a major issue, drastically inhibiting plant growth. The primary objective is to determine the root cause of the inconsistent wicking through experimental testing. Suspect causes for the capillary water column to break include: a vacuum effect due to a negative pressure gradient in the water reservoir, contamination of material due to minerals in water and back wash from plant fertilizer, induced air bubbles while using syringe refill method, and material limitations of Nomex's ability to absorb and retain water. Experimental testing will be conducted to systematically determine the cause of under and over-wicking. Pressure gages will be used to determine pressure drop during the course of the plant life cycle and during the water refill process. A debubbler device will be connected to a root mat in order to equalize pressure inside the reservoir. Moisture and evaporation tests will simultaneously be implemented to observe moisture content and wicking rates over the course of a plant cycle. Water retention tests will be performed using strips of Nomex to determine materials wicking rates, porosity, and absorptivity. Through these experimental tests, we will have a better understanding of material properties of Nomex, as well as determine the root cause of water column breakage. With consistent test results, a forward plan can be achieved to resolve the issue and give valuable insight for the next generation of VEGGIE.
2003-06-04
KENNEDY SPACE CENTER, FLA. - At Port Canaveral, the Pressurized Module of the Japanese Experiment Module (JEM) is lifted out of the ship’s cargo hold. It will be loaded onto the truck bed in the background for transfer to KSC’s Space Station Processing Facility. The container transport ship carrying JEM departed May 2 from Yokohama Harbor in Japan for the voyage to the United States. The National Space Development Agency of Japan (NASDA) developed the laboratory at the Tsukuba Space Center near Tokyo. The Pressurized Module is the first element of the JEM, named "Kibo" (Hope), to be delivered to KSC. The JEM is Japan's primary contribution to the Station. It will enhance the unique research capabilities of the orbiting complex by providing an additional environment for astronauts to conduct science experiments. The JEM also includes an exposed facility (platform) for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.
A preliminary look at techniques used to obtain airdata from flight at high angles of attack
NASA Technical Reports Server (NTRS)
Moes, Timothy R.; Whitmore, Stephen A.
1990-01-01
Flight research at high angles of attack has posed new problems for airdata measurements. New sensors and techniques for measuring the standard airdata quantities of static pressure, dynamic pressure, angle of attack, and angle of sideslip were subsequently developed. The ongoing airdata research supporting NASA's F-18 high alpha research program is updated. Included are the techniques used and the preliminary results. The F-18 aircraft was flown with three research airdata systems: a standard airdata probe on the right wingtip, a self-aligning airdata probe on the left wingtip, and a flush airdata system on the nose cone. The primary research goal was to obtain steady-state calibrations for each airdata system up to an angle of attack of 50 deg. This goal was accomplished and preliminary accuracies of the three airdata systems were assessed and are presented. An effort to improve the fidelity of the airdata measurements during dynamic maneuvering is also discussed. This involved enhancement of the aerodynamic data with data obtained from linear accelerometers, rate gyros, and attitude gyros. Preliminary results of this technique are presented.
Measurements of a turbulent horseshoe vortex formed around a cylinder
NASA Technical Reports Server (NTRS)
Eckerle, W. A.; Langston, L. S.
1986-01-01
An experimental investigation was conducted to characterize a symmetrical horseshoe vortex system in front of and around a single large-diameter right cylinder centered between the sidewalls of a wind tunnel. Surface flow visualization and surface static pressure measurements as well as extensive mean velocity and pressure measurements in and around the vortex system were acquired. The results lend new insight into the formation and development of the vortex system. Contrary to what has been assumed previously, a strong vortex was not identified in the streamwise plane of symmetry, but started a significant angular distance away from it. Rather than the multiple vortex systems reported by others, only a single primary vortex and saddle point were found. The scale of the separation process at the saddle point was much smaller than the scale of the approaching boundary layer thickness. Results of the present study not only shed light on such phenomena as the nonsymmetrical endwall flow in axial turbomachinery but can also be used as a test case for three-dimensional computational fluid mechanics computer codes.
Wang, Feng; Tzanakis, Iakovos; Eskin, Dmitry; Mi, Jiawei; Connolley, Thomas
2017-11-01
The cavitation-induced fragmentation of primary crystals formed in Al alloys were investigated for the first time by high-speed imaging using a novel experimental approach. Three representative primary crystal types, Al 3 Ti, Si and Al 3 V with different morphologies and mechanical properties were first extracted by deep etching of the corresponding Al alloys and then subjected to ultrasonic cavitation processing in distilled water. The dynamic interaction between the cavitation bubbles and primary crystals was imaged in situ and in real time. Based on the recorded image sequences, the fragmentation mechanisms of primary crystals were studied. It was found that there are three major mechanisms by which the primary crystals were fragmented by cavitation bubbles. The first one was a slow process via fatigue-type failure. A cyclic pressure exerted by stationary pulsating bubbles caused the propagation of a crack pre-existing in the primary crystal to a critical length which led to fragmentation. The second mechanism was a sudden process due to the collapse of bubbles in a passing cavitation cloud. The pressure produced upon the collapse of the cloud promoted rapid monotonic crack growth and fast fracture in the primary crystals. The third observed mechanism was normal bending fracture as a result of the high pressure arising from the collapse of a bubble cloud and the crack formation at the branch connection points of dendritic primary crystals. The fragmentation of dendrite branches due to the interaction between two freely moving dendritic primary crystals was also observed. A simplified fracture analysis of the observed phenomena was performed. The specific fragmentation mechanism for the primary crystals depended on their morphology and mechanical properties. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.
Ye, Peng; Vander Wal, Randy; Boehman, Andre L.; ...
2014-12-26
The effect of rail pressure and biodiesel fueling on the morphology of exhaust particulate agglomerates and the nanostructure of primary particles (soot) was investigated with a common-rail turbocharged direct injection diesel engine. The engine was operated at steady state on a dynamometer running at moderate speed with both low (30%) and medium–high (60%) fixed loads, and exhaust particulate was sampled for analysis. Ultra-low sulfur diesel and its 20% v/v blends with soybean methyl ester biodiesel were used. Fuel injection occurred in a single event around top dead center at three different injection pressures. Exhaust particulate samples were characterized with TEMmore » imaging, scanning mobility particle sizing, thermogravimetric analysis, Raman spectroscopy, and XRD analysis. Particulate morphology and oxidative reactivity were found to vary significantly with rail pressure and with biodiesel blend level. Higher biodiesel content led to increases in the primary particle size and oxidative reactivity but did not affect nanoscale disorder in the as-received samples. For particulates generated with higher injection pressures, the initial oxidative reactivity increased, but there was no detectable correlation with primary particle size or nanoscale disorder.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye, Peng; Vander Wal, Randy; Boehman, Andre L.
The effect of rail pressure and biodiesel fueling on the morphology of exhaust particulate agglomerates and the nanostructure of primary particles (soot) was investigated with a common-rail turbocharged direct injection diesel engine. The engine was operated at steady state on a dynamometer running at moderate speed with both low (30%) and medium–high (60%) fixed loads, and exhaust particulate was sampled for analysis. Ultra-low sulfur diesel and its 20% v/v blends with soybean methyl ester biodiesel were used. Fuel injection occurred in a single event around top dead center at three different injection pressures. Exhaust particulate samples were characterized with TEMmore » imaging, scanning mobility particle sizing, thermogravimetric analysis, Raman spectroscopy, and XRD analysis. Particulate morphology and oxidative reactivity were found to vary significantly with rail pressure and with biodiesel blend level. Higher biodiesel content led to increases in the primary particle size and oxidative reactivity but did not affect nanoscale disorder in the as-received samples. For particulates generated with higher injection pressures, the initial oxidative reactivity increased, but there was no detectable correlation with primary particle size or nanoscale disorder.« less
The Roles of Primary Cilia in Cardiovascular System
2016-10-01
mitochondrial generation of hydrogen peroxide. General properties and effect of hyperbaric oxygen . Biochem J 134:707–716. Boveris A, Oshino N, Chance B. 1972...The mitochondrial generation of hydrogen peroxide. General properties and effect of hyperbaric oxygen . Biochem J 134:707–716. Boveris A, Oshino N...Aim 1.2 (months 13-30): We will examine signaling mechanisms of cilia & their effects on blood pressure. Aim 2 (months 7-36). We will study
Bulk Shielding Facility quarterly report, April, May and June 1984
DOE Office of Scientific and Technical Information (OSTI.GOV)
Corbett, B.L.; Lance, E.D.
1984-12-01
The BSR operated at an average power level of 1310 kW for 3.8% of the time during April, May, and June. Water-quality control in both the reactor primary and secondary cooling systems was satisfactory. The PCA was used in training startups and was operated on five occasions for the NBS and HEDL recheck of a previous experiment run on the LWR pressure vessel surveillance dosimetry improvement program.
Worthley, Stephen G.; Tsioufis, Costas P.; Worthley, Matthew I.; Sinhal, Ajay; Chew, Derek P.; Meredith, Ian T.; Malaiapan, Yuvi; Papademetriou, Vasilios
2013-01-01
Aims Catheter-based renal artery sympathetic denervation has emerged as a novel therapy for treatment of patients with drug-resistant hypertension. Initial studies were performed using a single electrode radiofrequency catheter, but recent advances in catheter design have allowed the development of multi-electrode systems that can deliver lesions with a pre-determined pattern. This study was designed to evaluate the safety and efficacy of the EnligHTN™ multi-electrode system. Methods and results We conducted the first-in-human, prospective, multi-centre, non-randomized study in 46 patients (67% male, mean age 60 years, and mean baseline office blood pressure 176/96 mmHg) with drug-resistant hypertension. The primary efficacy objective was change in office blood pressure from baseline to 6 months. Safety measures included all adverse events with a focus on the renal artery and other vascular complications and changes in renal function. Renal artery denervation, using the EnligHTN™ system significantly reduced the office blood pressure from baseline to 1, 3, and 6 months by −28/10, −27/10 and −26/10 mmHg, respectively (P < 0.0001). No acute renal artery injury or other serious vascular complications occurred. Small, non-clinically relevant, changes in average estimated glomerular filtration rate were reported from baseline (87 ± 19 mL/min/1.73 m2) to 6 months post-procedure (82 ± 20 mL/min/1.73 m2). Conclusion Renal sympathetic denervation, using the EnligHTN™ multi-electrode catheter results in a rapid and significant office blood pressure reduction that was sustained through 6 months. The EnligHTN™ system delivers a promising therapy for the treatment of drug-resistant hypertension. PMID:23782649
Worthley, Stephen G; Tsioufis, Costas P; Worthley, Matthew I; Sinhal, Ajay; Chew, Derek P; Meredith, Ian T; Malaiapan, Yuvi; Papademetriou, Vasilios
2013-07-01
Catheter-based renal artery sympathetic denervation has emerged as a novel therapy for treatment of patients with drug-resistant hypertension. Initial studies were performed using a single electrode radiofrequency catheter, but recent advances in catheter design have allowed the development of multi-electrode systems that can deliver lesions with a pre-determined pattern. This study was designed to evaluate the safety and efficacy of the EnligHTN(™) multi-electrode system. We conducted the first-in-human, prospective, multi-centre, non-randomized study in 46 patients (67% male, mean age 60 years, and mean baseline office blood pressure 176/96 mmHg) with drug-resistant hypertension. The primary efficacy objective was change in office blood pressure from baseline to 6 months. Safety measures included all adverse events with a focus on the renal artery and other vascular complications and changes in renal function. Renal artery denervation, using the EnligHTN system significantly reduced the office blood pressure from baseline to 1, 3, and 6 months by -28/10, -27/10 and -26/10 mmHg, respectively (P < 0.0001). No acute renal artery injury or other serious vascular complications occurred. Small, non-clinically relevant, changes in average estimated glomerular filtration rate were reported from baseline (87 ± 19 mL/min/1.73 m2) to 6 months post-procedure (82 ± 20 mL/min/1.73 m2). Renal sympathetic denervation, using the EnligHTN multi-electrode catheter results in a rapid and significant office blood pressure reduction that was sustained through 6 months. The EnligHTN system delivers a promising therapy for the treatment of drug-resistant hypertension.
Primary propulsion/large space system interaction study
NASA Technical Reports Server (NTRS)
Coyner, J. V.; Dergance, R. H.; Robertson, R. I.; Wiggins, J. V.
1981-01-01
An interaction study was conducted between propulsion systems and large space structures to determine the effect of low thrust primary propulsion system characteristics on the mass, area, and orbit transfer characteristics of large space systems (LSS). The LSS which were considered would be deployed from the space shuttle orbiter bay in low Earth orbit, then transferred to geosynchronous equatorial orbit by their own propulsion systems. The types of structures studied were the expandable box truss, hoop and column, and wrap radial rib each with various surface mesh densities. The impact of the acceleration forces on system sizing was determined and the effects of single point, multipoint, and transient thrust applications were examined. Orbit transfer strategies were analyzed to determine the required velocity increment, burn time, trip time, and payload capability over a range of final acceleration levels. Variables considered were number of perigee burns, delivered specific impulse, and constant thrust and constant acceleration modes of propulsion. Propulsion stages were sized for four propellant combinations; oxygen/hydrogen, oxygen/methane, oxygen/kerosene, and nitrogen tetroxide/monomethylhydrazine, for pump fed and pressure fed engine systems. Two types of tankage configurations were evaluated, minimum length to maximize available payload volume and maximum performance to maximize available payload mass.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Akarsu, A.N.; Hossain, A.; Sarfarazi, M.
1996-01-22
Primary congenital glaucoma (gene symbol: GLC3) is characterized by an improper development of the aqueous outflow system. The reduced outflow of fluid results in an increased intraocular pressure leading to buphthalmos, optic nerve damage, and eventual visual impairment. GLC3 is a heterogeneous condition with an estimated incidence of 1:2,500 in Middle Eastern and 1:10,000 in Western countries. In many families, GLC3 is an autosomal recessive trait with presentation of an earlier age-of-onset, high intraocular pressure, enlarged cloudy cornea, buphthalmos, and a more aggressive course. The pathogenesis of GLC3 remains elusive despite extensive histologic efforts to identify a single anatomic defect.more » Recent advances in positional mapping and cloning of human disorders provided an opportunity to identify chromosome locations of the GLC3 phenotype. Our laboratory is currently involved in the mapping of this condition by using a combination of candidate chromosome regions associated with the GLC3 phenotype and by a general positional mapping strategy. 16 refs., 3 tabs.« less
McManus, Richard J; Roalfe, Andrea; Fletcher, Kate; Taylor, Clare J; Martin, Una; Virdee, Satnam; Greenfield, Sheila; Hobbs, F D Richard
2016-01-01
Objective To assess whether using intensive blood pressure targets leads to lower blood pressure in a community population of people with prevalent cerebrovascular disease. Design Open label randomised controlled trial. Setting 99 general practices in England, with participants recruited in 2009-11. Participants People with a history of stroke or transient ischaemic attack whose systolic blood pressure was 125 mm Hg or above. Interventions Intensive systolic blood pressure target (<130 mm Hg or 10 mm Hg reduction from baseline if this was <140 mm Hg) or standard target (<140 mm Hg). Apart from the different target, patients in both arms were actively managed in the same way with regular reviews by the primary care team. Main outcome measure Change in systolic blood pressure between baseline and 12 months. Results 529 patients (mean age 72) were enrolled, 266 to the intensive target arm and 263 to the standard target arm, of whom 379 were included in the primary analysis (182 (68%) intensive arm; 197 (75%) standard arm). 84 patients withdrew from the study during the follow-up period (52 intensive arm; 32 standard arm). Mean systolic blood pressure dropped by 16.1 mm Hg to 127.4 mm Hg in the intensive target arm and by 12.8 mm Hg to 129.4 mm Hg in the standard arm (difference between groups 2.9 (95% confidence interval 0.2 to 5.7) mm Hg; P=0.03). Conclusions Aiming for target below 130 mm Hg rather than 140 mm Hg for systolic blood pressure in people with cerebrovascular disease in primary care led to a small additional reduction in blood pressure. Active management of systolic blood pressure in this population using a <140 mm Hg target led to a clinically important reduction in blood pressure. Trial registration Current Controlled Trials ISRCTN29062286. PMID:26919870
Phillips, Y Y
1986-12-01
Injury from explosion may be due to the direct cussive effect of the blast wave (primary), being struck by material propelled by the blast (secondary), to whole-body displacement and impact (tertiary), or to miscellaneous effects from burns, toxic acids, and so on. Severe primary blast injury is most likely to be seen in military operations but can occur in civilian industrial accidents or terrorist actions. Damage is seen almost exclusively in air-containing organs--the lungs, the gastrointestinal tract, and the auditory system. Pulmonary injury is characterized by pneumothorax, parenchymal hemorrhage, and alveolar rupture. The last is responsible for the arterial air embolism that is the principle cause of early mortality. Treatment for blast injury is similar to that for blunt trauma. The sequalae of air embolization to the cerebral or coronary circulation may be altered by immediate hyperbaric therapy. Use of positive pressure ventilatory systems should be closely monitored as they may increase the risk of air embolism in pneumothorax. Morbidity and mortality may be increased by strenuous exertion after injury and by the wearing of a cloth ballistic vest at the time of the blast.
Feng, Weijing; Cai, Qingqing; Yuan, Woliang; Liu, Yu; Bardeesi, Adham Sameer A; Wang, Jingfeng; Chen, Jie; Huang, Hui
2016-02-01
The interactions of sodium balance and response of renin-angiotensin-aldosterone system are important for maintaining the hemodynamic stability in physiological conditions. However, the influence of short-term sodium intake intervention in the response of renin-angiotensin system (RAS) on hypertensive patients is still unclear. Thus, we conducted a clinical trial to investigate the effects of short-term sodium intake intervention on the response of RAS in hypertensive patients.One hundred twenty-five primary Chinese hypertensive patients were divided into high, moderate, and low sodium groups by 24-hour urinary sodium excretion (UNa). All the patients received a 10-day dietary sodium intake intervention with standardized sodium (173.91mmol/day) and potassium (61.53mmol/day). Blood pressure, urinary sodium, urinary potassium, plasma sodium, potassium, creatinine, the levels of plasma renin activity, plasma angiotensin II concentrations (AT-II), and plasma aldosterone concentrations were detected before and after the intervention.Before the intervention, no differences were found in blood pressure and RAS among 3 groups. After standardized dietary sodium intake intervention, both UNa excretion and systolic pressure decreased in high-sodium group, while they increased in moderate and low-sodium groups. Intriguingly, there were no changes in the levels of plasma renin activity, AT-II, and plasma aldosterone concentrations among 3 groups during the intervention.The present study demonstrated that the influenced sodium excretion and blood pressure by short-term sodium intake intervention were independent of RAS quick response in Chinese hypertensive patients.
Feng, Weijing; Cai, Qingqing; Yuan, Woliang; Liu, Yu; Bardeesi, Adham Sameer A.; Wang, Jingfeng; Chen, Jie; Huang, Hui
2016-01-01
Abstract The interactions of sodium balance and response of renin–angiotensin–aldosterone system are important for maintaining the hemodynamic stability in physiological conditions. However, the influence of short-term sodium intake intervention in the response of renin–angiotensin system (RAS) on hypertensive patients is still unclear. Thus, we conducted a clinical trial to investigate the effects of short-term sodium intake intervention on the response of RAS in hypertensive patients. One hundred twenty-five primary Chinese hypertensive patients were divided into high, moderate, and low sodium groups by 24-hour urinary sodium excretion (UNa+). All the patients received a 10-day dietary sodium intake intervention with standardized sodium (173.91mmol/day) and potassium (61.53mmol/day). Blood pressure, urinary sodium, urinary potassium, plasma sodium, potassium, creatinine, the levels of plasma renin activity, plasma angiotensin II concentrations (AT-II), and plasma aldosterone concentrations were detected before and after the intervention. Before the intervention, no differences were found in blood pressure and RAS among 3 groups. After standardized dietary sodium intake intervention, both UNa+ excretion and systolic pressure decreased in high-sodium group, while they increased in moderate and low-sodium groups. Intriguingly, there were no changes in the levels of plasma renin activity, AT-II, and plasma aldosterone concentrations among 3 groups during the intervention. The present study demonstrated that the influenced sodium excretion and blood pressure by short-term sodium intake intervention were independent of RAS quick response in Chinese hypertensive patients. PMID:26871780
Hypertension in children and adolescents: epidemiology and pathogenesis.
Raj, Manu; Krishnakumar, R
2013-03-01
High blood pressure is one among the leading contributors to burden of disease globally. Approximately 54 % of stroke and 47 % of ischemic heart disease events worldwide were attributable to high blood pressure in the year 2001. There is deficiency of data on the long-term outcome of hypertension in children. In spite of this, there is sufficient evidence to suspect that the health risks of hypertension in pediatric patients are substantial. Hypertension in childhood is known to result in hypertension in young adulthood. The epidemiology of hypertension in children is well represented from various studies conducted across continents. Factors like methodological issues in measurement, socio demographic differences, adiposity levels and ethnicity appear to influence the distribution of blood pressure as well as prevalence of hypertension in children. The etio-pathogenesis of essential (primary) hypertension is multi-factorial in origin. Obesity, insulin resistance, activation of sympathetic nervous system, alterations in sodium homeostasis, renin-angiotensin system changes, changes in vascular smooth muscle structure and reactivity, high serum uric acid levels, genetic factors and fetal programming have been reported to contribute to this disorder. The causes of secondary hypertension vary with age. Renal disorders and coarctation of the aorta are the most common causes of hypertension in children up to age 6 y. In older children, renal parenchymal disease remains the most frequent cause of increased blood pressure. Other causes of hypertension in children are relatively rare and include systemic arteritis and certain tumours, endocrine dysfunction, and neurologic disorders.
Synthesis of Organic Matter of Prebiotic Chemistry at the Protoplanetary Disc
NASA Astrophysics Data System (ADS)
Snytnikov, Valeriy; Stoynovskaya, Olga; Rudina, Nina
We have carried out scanning electron microscopic examination of CM carbonaceous chondrites meteorites Migey, Murchison, Staroe Boriskino aged more than 4.56 billion years (about 50 million years from the beginning of the formation of the Solar system). Our study confirmed the conclusion of Rozanov, Hoover and other researchers about the presence of microfossils of bacterial origin in the matrix of all these meteorites. Since the time of the Solar system formation is 60 - 100 million years, the primary biocenosis emerged in the protoplanetary disc of the Solar system before meteorites or simultaneously with them. It means that prebiological processes and RNA world appeared even earlier in the circumsolar protoplanetary disc. Most likely, this appearance of prebiotic chemistry takes place nowday in massive and medium-massive discs of the observed young stellar objects (YSO) class 0 and I. The timescale of the transition from chemical to biological evolution took less than 50 million years for the Solar system. Further evolution of individual biocenosis in a protoplanetary disc associated with varying physico-chemical conditions during the formation of the Solar system bodies. Biocenosis on these bodies could remove or develop under the influence of many cosmic factors and geological processes in the case of Earth. To complete the primary biosphere formation in short evolution time - millions of years - requires highly efficient chemical syntheses. In industrial chemistry for the efficient synthesis of ammonia, hydrogen cyanide, methanol and other organic species, that are the precursors to obtain prebiotic compounds, catalytic reactors of high pressure are used. Thus (1) necessary amount of the proper catalyst in (2) high pressure areas of the disc can trigger these intense syntheses. The disc contains the solids with the size from nanoparticle to pebble. Iron and magnesium is catalytically active ingredient for such solids. The puzzle is a way to provide hydrogen pressure inside the disc from tens to hundred atmospheres. We simulated unsteady processes in massive circumstellar discs around YSO class O and I. In the computational experiments, we have shown that at a certain stage of its evolution the circumstellar discs of gas and solids produces local areas of high pressure. According to the classical heterogeneous catalysis, a wide range of organic and prebiotic compounds could have been synthesized in these areas. Can we capture these areas of high pressure synthesis in observation of circumstellar discs? Due to the small sizes of such areas they can be hardly ever resolved even with the modern telescopes such as ALMA. However, we can try to detect their signatures in the disc, since the gas of the disc keep the set of organic synthesis products. The idea is to define the signature of the process using laboratory experiments. Varying gas temperature and pressure in laboratory setup we can carry out the catalytic high pressure syntheses and specify the set of gaseous products. These sets of organic compounds observed in the discs may serve as indicators of the emergence of high-pressure areas of prebiotic chemistry. Thus, there is a special interest to the study of YSO class 0 and I by means of observational astronomy. For these objects, first data on the presence of individual organic compounds in massive hydrogen-helium component of the discs appear. The origin of the organic compounds that are associated with chemical reactions in the discs should be separated from the set of organic compounds of the initial molecular cloud.
Takase, Yasushi; Nakano, Misa; Tatsumi, Chikao
2003-09-01
Although the primary chronic daily headache is subdivided into chronic migraine, chronic tension-type headache, hemicrania continua, and new daily persistent headache (NDPH), the characteristics of NDPH have not been well studied in Japan. The purpose of this study is to investigate the clinical characteristics of the primary NDPH. Twenty-one men and twenty-two women with primary NDPH, aged 14 to 73 years were diagnosed at Toyonaka Municipal Hospital from November 1997 to April 2003. Age of the onset ranged from 13 to 73 years (mean, 34.8). The onset of headache occurred in relation to a stressful life event in 16%, a systemic infection in 12% and an extracranial surgery in 7%. Any precipitating events could not be identified in approximately two-third of patients (65%). Quality of the headache was described as dull and/or pressure-like sensation in 91%, throbbing and/or pulsating sensation in 28%. NDPH needs further study, because it appears to be one of the most refractory headaches.
Liu, Hong; Wang, Hai-Bo; Wu, Lin; Wang, Shi-Jun; Yang, Ze-Chuan; Ma, Run-Yi; Reilly, Kathleen H; Yan, Xiao-Yan; Ji, Ping; Wu, Yang-feng
2016-01-06
Patients with cervical spondylosis myelopathy (CSM) and complicated with hypertension are often experiencing a blood pressure decrease after taking cervical decompressive surgery in clinical observations, but how this blood pressure reduction is associated with the surgery, which cut cervical sympathetic nervous, has never been rigorously assessed. Thus, the purpose of this study is to investigate the effect of cervical decompressive surgery on blood pressure among CSM patients with hypertension. The study will be a time series cohort study. Fifty eligible patients will be selected consecutively from the Peking University First Hospital. Two 24-h ambulatory blood pressure measurement (ABPM) will be taken before the surgery, apart by at least 3 days. The patients will be followed up for another two ABPMs at 1 and 3 months after the surgery. We will recruit subjects with cervical spondylosis myelopathy meeting operation indications and scheduled for receiving cervical decompressive surgery, aged 18-84 years, have a history of hypertension or office systolic blood pressure ≥140 mmHg on initial screening, and willing to participate in the study and provide informed consent. Exclusion criteria includes a history of known secondary hypertension, visual analogue scale (VAS) score ≥4, and unable to comply with study due to severe psychosis. The change in systolic ABPs over the four times will be analyzed to observe the overall pattern of the blood pressure change in relation to the surgery, but the primary analysis will be the comparison of systolic ABP between the 2(nd) and 3(rd), 4(th) measurements (before and after the surgery). We will also calculate the regression-to-the-mean adjusted changes in systolic ABP as sensitivity analysis. Secondary endpoints are the changes in 24 h ABPM diastolic blood pressure, blood pressure control status, the use and dose adjustment of antihypertensive medication, and the incidence of operative complications. Primary outcome analyses will be carried out using analysis of covariance, as well as the first secondary endpoint. This study will inform us the important knowledge about cervical sympathetic nervous system (SNS) and blood pressure. Once confirmed, it may help to produce new method for control of hypertension, which is the leading cause of death in the world. The study is registered to Clinical Trials.gov (NCT02016768).
Effect of shroud geometry on the effectiveness of a short mixing stack gas eductor model
NASA Astrophysics Data System (ADS)
Kavalis, A. E.
1983-06-01
An existing apparatus for testing models of gas eductor systems using high temperature primary flow was modified to provide improved control and performance over a wide range of gas temperature and flow rates. Secondary flow pumping, temperature and pressure data were recorded for two gas eductor system models. The first, previously tested under hot flow conditions, consists of a primary plate with four tilted-angled nozzles and a slotted, shrouded mixing stack with two diffuser rings (overall L/D = 1.5). A portable pyrometer with a surface probe was used for the second model in order to identify any hot spots at the external surface of the mixing stack, shroud and diffuser rings. The second model is shown to have almost the same mixing and pumping performance with the first one but to exhibit much lower shroud and diffuser surface temperatures.
... in salt and water build-up and a rise in blood pressure. Uncontrolled high blood pressure can put you at risk for ... tumor in one adrenal gland (also called Conn’s syndrome), which occurs in about one-third of ... High blood pressure that requires more than three medications ...
NASA Astrophysics Data System (ADS)
Katsuyama, Jinya; Uno, Shumpei; Watanabe, Tadashi; Li, Yinsheng
2018-03-01
The thermal hydraulic (TH) behavior of coolant water is a key factor in the structural integrity assessments on reactor pressure vessels (RPVs) of pressurized water reactors (PWRs) under pressurized thermal shock (PTS) events, because the TH behavior may affect the loading conditions in the assessment. From the viewpoint of TH behavior, configuration of plant equipment and their dimensions, and operator action time considerably influence various parameters, such as the temperature and flow rate of coolant water and inner pressure. In this study, to investigate the influence of the operator action time on TH behavior during a PTS event, we developed an analysis model for a typical Japanese PWR plant, including the RPV and the main components of both primary and secondary systems, and performed TH analyses by using a system analysis code called RELAP5. We applied two different operator action times based on the Japanese and the United States (US) rules: Operators may act after 10 min (Japanese rules) and 30 min (the US rules) after the occurrence of PTS events. Based on the results of TH analysis with different operator action times, we also performed structural analyses for evaluating thermal-stress distributions in the RPV during PTS events as loading conditions in the structural integrity assessment. From the analysis results, it was clarified that differences in operator action times significantly affect TH behavior and loading conditions, as the Japanese rule may lead to lower stresses than that under the US rule because an earlier operator action caused lower pressure in the RPV.
Experimental evaluation of environmental scanning electron microscopes at high chamber pressure.
Fitzek, H; Schroettner, H; Wagner, J; Hofer, F; Rattenberger, J
2015-11-01
In environmental scanning electron microscopy (ESEM) high pressure applications have become increasingly important. Wet or biological samples can be investigated without time-consuming sample preparation and potential artefacts from this preparation can be neglected. Unfortunately, the signal-to-noise ratio strongly decreases with increasing chamber pressure. To evaluate the high pressure performance of ESEM and to compare different electron microscopes, information about spatial resolution and detector type is not enough. On the one hand, the scattering of the primary electron beam increases, which vanishes the contrast in images; and on the other hand, the secondary electrons (SE) signal amplification decreases. The stagnation gas thickness (effective distance the beam has to travel through the imaging gas) as well as the SE detection system depend on the microscope and for a complete and serious evaluation of an ESEM or low vacuum SEM it is necessary to specify these two parameters. A method is presented to determine the fraction of scattered and unscattered electrons and to calculate the stagnation gas thickness (θ). To evaluate the high pressure performance of the SE detection system, a method is presented that allows for an analysis of a single image and the calculation of the signal-to-noise ratio of this image. All investigations are performed on an FEI ESEM Quanta 600 (field emission gun) and an FEI ESEM Quanta 200 (thermionic gun). These methods and measurements should represent opportunities for evaluating the high pressure performance of an ESEM. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.
NASA Astrophysics Data System (ADS)
Miyagi, L. M.; Kunz, M.; Couper, S.; Lin, F.; Yan, J.; Doran, A.; MacDowell, A. A.
2017-12-01
The rheology of rocks and minerals in the Earth's deep interior plays a primary role in controlling large scale geodynamic processes such as mantle convection and slab subduction. Plastic deformation resulting from these processes can lead to texture development and associated seismic anisotropy. If a detailed understanding of the link between deformation and seismic anisotropy is established, observations of seismic anisotropy can be used to understand the dynamic state in the deep Earth. However, performing deformation experiments at lower mantle pressure and temperature conditions are extremely challenging. Thus most deformation studies have been performed either at room temperature and high pressure or at reduced pressures and high temperature. Only a few extraordinary efforts have attained pressures and temperatures relevant to lower mantle. Therefore our ability to interpret observations of lower mantle seismic anisotropy in terms of mantle flow models remains limited. In order to expand the pressure and temperature range available for deformation of deep Earth relevant mineral phases, we have developed a laser heating system for in-situ double-sided heating in radial diffraction geometry at beamline 12.2.2 of the Advanced Light Source of Lawrence Berkeley National Laboratory. This allows texture and lattice strain measurements to be recorded at simultaneous high pressures and temperatures in the diamond anvil cell. This new system is integrated into the newly built axial laser heating system to allow for rapid and reliable transitioning between double-sided laser heating in axial and radial geometries. Transitioning to radial geometry is accomplished by redirecting the laser and imaging paths from 0° and 180° to 90° and 270°. To redirect the 90° path, a motorized periscope mirror pair with an objective lens can be inserted into the downstream axial beam path. The 270° redirection is accomplished by removing the upstream axial objective lens and manually installing a small assembly carrying 2 infrared mirrors and an objective lens. Using this system we have performed two pilot studies recording texture and lattice strain development during deformation of FeO up to 1300 K and 45 GPa and bridgmanite up to 1600 K and 80 GPa.
NASA Astrophysics Data System (ADS)
Dalton, John A.; Wood, Bernard J.
1993-10-01
We have experimentally determined the composition of near-soldus melts from depleted natural Iherzolite at pressures greater than 25 kbar. The melts are carbontitic with low alkali contents and Ca/(Ca + Mg) ratios of 0.72-0.74. Primary carbonate melts from fertile mantle are more sodic with Ca/(Ca + Mg + Fe + Na) of 0.52 and Na/(Na + Ca + Mg + Fe) up to 0.15. The melt compositions are similar to many natural magnesio-carbonatites, but differ substantially from the more abundant calcio-carbonatites. Experimentally we find that calcio-carbonatites are produced by wallrock reaction of primary melts with harzburgite at pressures of less than 25 kbar. At 15 kbar we have obtained a Ca/(Ca + Mg + Fe + Na) ratio of up to 0.87 and very low Na contents generated by this process. Values of Ca/(Ca + Mg + Fe + Na) up to 0.95 are possible at lower pressures. Low pressure wallrock reaction of primary carbonate melt with fertile Iherzolite produces melts richer in Na2CO3, corresponding to possible parental magmas of natrocarbonatite. Wallrock reaction at low pressures transforms the bulk peridotite composition from that of a harzburgite or Iherzolite to wehrlite. Examples of such carbonatite metasomatism are now widely documented. Our experiments show that the calcium content of olivine and the jadeite content of clinopyroxene may be used to constrain the Ca and Na contents respectively of the cabonatite melt responsible for metasomatism.
Bernardi, L; Passino, C; Porta, C; Anesi, E; Palladini, G; Merlini, G
2002-01-01
Objective: To investigate the possible causes of abnormal blood pressure control in light chain related (primary, AL) amyloidosis. Design: Cardiovascular, autonomic, and respiratory response to passive tilting were investigated in 51 patients with primary amyloidosis (mean (SEM) age 56 (2) years) and in 20 age matched controls. Spontaneous fluctuations in RR interval, respiration, end tidal carbon dioxide, blood pressure, and skin microcirculation were recorded during supine rest and with tilting. The values were subjected to spectral analysis to assess baroreflex sensitivity and the autonomic modulation of cardiac and vascular responses. Setting: Tertiary referral centre. Results: Autonomic modulation of the heart and blood pressure was nearly absent in the patients with amyloidosis: thus baroreflex sensitivity and the low frequency (0.1 Hz) fluctuations in all cardiovascular signals were severely reduced (p < 0.01 or more), as were respiratory fluctuations in the RR interval, and no change was observed upon tilting. Despite reduced autonomic modulation, blood pressure remained relatively stable in the amyloid group from supine to tilting. End tidal carbon dioxide was reduced in the amyloid patients (p < 0.001) indicating persistent hyperventilation; the breathing rate correlated inversely with the fall in blood pressure on tilting (p < 0.05). Conclusions: In primary amyloidosis, pronounced abnormalities in arterial baroreflexes and cardiovascular autonomic modulation to the heart and the vessels may be partly compensated for by hyperventilation at a slow breathing rate. PMID:12433892
Nonlinear Bubble Interactions in Acoustic Pressure Fields
NASA Technical Reports Server (NTRS)
Barbat, Tiberiu; Ashgriz, Nasser; Liu, Ching-Shi
1996-01-01
The systems consisting of a two-phase mixture, as clouds of bubbles or drops, have shown many common features in their responses to different external force fields. One of particular interest is the effect of an unsteady pressure field applied to these systems, case in which the coupling of the vibrations induced in two neighboring components (two drops or two bubbles) may result in an interaction force between them. This behavior was explained by Bjerknes by postulating that every body that is moving in an accelerating fluid is subjected to a 'kinetic buoyancy' equal with the product of the acceleration of the fluid multiplied by the mass of the fluid displaced by the body. The external sound wave applied to a system of drops/bubbles triggers secondary sound waves from each component of the system. These secondary pressure fields integrated over the surface of the neighboring drop/bubble may result in a force additional to the effect of the primary sound wave on each component of the system. In certain conditions, the magnitude of these secondary forces may result in significant changes in the dynamics of each component, thus in the behavior of the entire system. In a system containing bubbles, the sound wave radiated by one bubble at the location of a neighboring one is dominated by the volume oscillation mode and its effects can be important for a large range of frequencies. The interaction forces in a system consisting of drops are much smaller than those consisting of bubbles. Therefore, as a first step towards the understanding of the drop-drop interaction subject to external pressure fluctuations, it is more convenient to study the bubble interactions. This paper presents experimental results and theoretical predictions concerning the interaction and the motion of two levitated air bubbles in water in the presence of an acoustic field at high frequencies (22-23 KHz).
Focus on prevention, diagnosis and treatment of hypertension in children and adolescents
2013-01-01
The European Society of Hypertension has recently published its recommendations on prevention, diagnosis and treatment of high blood pressure in children and adolescents. Taking this contribution as a starting point the Study Group of Hypertension of the Italian Society of Pediatrics together with the Italian Society of Hypertension has conducted a reappraisal of the most recent literature on this subject. The present review does not claim to be an exhaustive description of hypertension in the pediatric population but intends to provide Pediatricians with practical and updated indications in order to guide them in this often unappreciated problem. This document pays particular attention to the primary hypertension which represents a growing problem in children and adolescents. Subjects at elevated risk of hypertension are those overweight, with low birth weight and presenting a family history of hypertension. However, also children who do not present these risk factors may have elevated blood pressure levels. In pediatric age diagnosis of hypertension or high normal blood pressure is made with repeated office blood pressure measurements that show values exceeding the reference values. Blood pressure should be monitored at least once a year with adequate methods and instrumentation and the observed values have to be interpreted according to the most updated nomograms that are adjusted for children’s gender, age and height. Currently other available methods such as ambulatory blood pressure monitoring and home blood pressure measurement are not yet adequately validated for use as diagnostic instruments. To diagnose primary hypertension it is necessary to exclude secondary forms. The probability of facing a secondary form of hypertension is inversely proportional to the child’s age and directly proportional to blood pressure levels. Medical history, clinical data and blood tests may guide the differential diagnosis of primary versus secondary forms. The prevention of high blood pressure is based on correct lifestyle and nutrition, starting from childhood age. The treatment of primary hypertension in children is almost exclusively dietary/behavioral and includes: a) reduction of overweight whenever present b) reduction of dietary sodium intake c) increase in physical activity. Pharmacological therapy will be needed rarely and only in specific cases. PMID:23510329
The difference in blood pressure readings between arms and survival: primary care cohort study.
Clark, Christopher E; Taylor, Rod S; Shore, Angela C; Campbell, John L
2012-03-20
To determine whether a difference in systolic blood pressure readings between arms can predict a reduced event free survival after 10 years. Cohort study. Rural general practice in Devon, United Kingdom. 230 people receiving treatment for hypertension in primary care. Bilateral blood pressure measurements recorded at three successive surgery attendances. Cardiovascular events and deaths from all causes during a median follow-up of 9.8 years. At recruitment 24% (55/230) of participants had a mean interarm difference in systolic blood pressure of 10 mm Hg or more and 9% (21/230) of 15 mm Hg or more; these differences were associated with an increased risk of all cause mortality (adjusted hazard ratio 3.6, 95% confidence interval 2.0 to 6.5 and 3.1, 1.6 to 6.0, respectively). The risk of death was also increased in 183 participants without pre-existing cardiovascular disease with an interarm difference in systolic blood pressure of 10 mm Hg or more or 15 mm Hg or more (2.6, 1.4 to 4.8 and 2.7, 1.3 to 5.4). An interarm difference in diastolic blood pressure of 10 mm Hg or more was weakly associated with an increased risk of cardiovascular events or death. Differences in systolic blood pressure between arms can predict an increased risk of cardiovascular events and all cause mortality over 10 years in people with hypertension. This difference could be a valuable indicator of increased cardiovascular risk. Bilateral blood pressure measurements should become a routine part of cardiovascular assessment in primary care.
Noro, Takahiko; Nakamoto, Kenji; Sato, Makoto; Yasuda, Noriko; Ito, Yoshinori; Ogawa, Shumpei; Nakano, Tadashi; Tsuneoka, Hiroshi
2014-10-01
We retrospectively examined intraocular pressure variations after visual field examination in primary open angle glaucoma (POAG), together with its influencing factors and its association with 24-hour intraocular pressure variations. Subjects were 94 eyes (52 POAG patients) subjected to measurements of 24-hour intraocular pressure and of changes in intraocular pressure after visual field examination using a Humphrey Visual Field Analyzer. Subjects were classified into three groups according to the magnitude of variation (large, intermediate and small), and 24-hour intraocular pressure variations were compared among the three groups. Factors influencing intraocular pressure variations after visual field examination and those associated with the large variation group were investigated. Average intraocular pressure variation after visual field examination was -0.28 ± 1.90 (range - 6.0(-) + 5.0) mmHg. No significant influencing factors were identified. The intraocular pressure at 3 a.m. was significantly higher in the large variation group than other two groups (p < 0.001). Central corneal thickness was correlated with the large variation group (odds ratio = 1.04; 95% confidence interval, 1.01-1.07 ; p = 0.02). No particular tendencies in intraocular pressure variations were found after visual field examination. Increases in intraocular pressure during the night might be associated with large intraocular pressure variations after visual field examination.
Muhihi, Alfa J; Njelekela, Marina A; Mpembeni, Rose N M; Muhihi, Bikolimana G; Anaeli, Amani; Chillo, Omary; Kubhoja, Sulende; Lujani, Benjamin; Maghembe, Mwanamkuu; Ngarashi, Davis
2018-02-13
Whilst the burden of non-communicable diseases is increasing in developing countries, little data is available on blood pressure among Tanzanian children. This study aimed at determining the blood pressure profiles and risk factors associated with elevated blood pressure among primary school children in Dar es Salaam, Tanzania. We conducted a cross sectional survey among 446 children aged 6-17 years from 9 randomly selected primary schools in Dar es Salaam. We measured blood pressure using a standardized digital blood pressure measuring machine (Omron Digital HEM-907, Tokyo, Japan). We used an average of the three blood pressure readings for analysis. Elevated blood pressure was defined as average systolic or diastolic blood pressure ≥ 90th percentile for age, gender and height. The proportion of children with elevated blood pressure was 15.2% (pre-hypertension 4.4% and hypertension 10.8%). No significant gender differences were observed in the prevalence of elevated BP. Increasing age and overweight/obese children were significantly associated with elevated BP (p = 0.0029 and p < 0.0001) respectively. Similar associations were observed for age and overweight/obesity with hypertension. (p = 0.0506 and p < 0.0001) respectively. In multivariate analysis, age above 10 years (adjusted RR = 3.63, 95% CI = 1.03-7.82) was significantly and independently associated with elevated BP in this population of school age children. We observed a higher proportion of elevated BP in this population of school age children. Older age and overweight/obesity were associated with elevated BP. Assessment of BP and BMI should be incorporated in school health program in Tanzania to identify those at risk so that appropriate interventions can be instituted before development of associated complications.
Zhu, Hang; Xue, Hao; Wang, Guangyi; Fu, Zhenhong; Liu, Jie; Shi, Yajun
2015-04-01
To explore the association between urinary microalbumin-to-creatinine ratio (ACR) and brachial-ankle pulse wave velocity (baPWV) in hypertensive patients. A total of 877 primary hypertension patients were enrolled in this trial from September 2009 to December 2012, and were randomly recruited and patients were divided into normal ACR group (ACR < 30 mg/g, n = 723), micro-albuminuria group (30 mg/g ≤ ACR < 300 mg/g, n = 136) and macro-albuminuria group (ACR ≥ 300 mg/g, n = 18). baPWV was measure by automatic pulse wave velocity measuring system. The baPWV values in patients of micro-albuminuria group and macro-albuminuria group were significantly higher than in the normal ACR group (all P < 0.05). The baPWV value of macro-albuminuria group was significantly higher than in the micro-albuminuria group (P < 0.05). Linear correlation analysis revealed that ACR was positively correlated with baPWV (r = 0.413, P < 0.01). Multiple linear regression analysis showed that ACR independently correlated with baPWV in patients with primary hypertension (β = 0.29, R(2) = 0.112, P < 0.01) after adjusting for age, sex, body mass index, systolic blood pressure, diastolic blood pressure, blood glucose, total cholesterol, low density lipoprotein, high density lipoprotein and triglyceride. Using ACR < 30 mg/g and ACR ≥ 30 mg/g as dichotomous variable, binary logistic regression analysis showed that ACR ≥ 30 mg/g was also a risk factor of the ascending baPWV in primary hypertension patients (OR: 1.73, 95% CI: 1.62-2.98) after adjusting the traditional cardiovascular risk factors. ACR is positively correlated to baPWV in primary hypertension patients, and the ascending baPWV is a risk factor of early renal dysfunction in primary hypertension patients.
Vaporization Would Cool Primary Battery
NASA Technical Reports Server (NTRS)
Bhandari, Pradeep; Miyake, Robert N.
1991-01-01
Temperature of discharging high-power-density primary battery maintained below specified level by evaporation of suitable liquid from jacket surrounding battery, according to proposal. Pressure-relief valve regulates pressure and boiling temperature of liquid. Less material needed in cooling by vaporization than in cooling by melting. Technique used to cool batteries in situations in which engineering constraints on volume, mass, and location prevent attachment of cooling fins, heat pipes, or like.
Indirect gonioscopy system for imaging iridocorneal angle of eye
NASA Astrophysics Data System (ADS)
Perinchery, Sandeep M.; Fu, Chan Yiu; Baskaran, Mani; Aung, Tin; Murukeshan, V. M.
2017-08-01
Current clinical optical imaging systems do not provide sufficient structural information of trabecular meshwork (TM) in the iridocorneal angle (ICA) of the eye due to their low resolution. Increase in the intraocular pressure (IOP) can occur due to the abnormalities in TM, which could subsequently lead to glaucoma. Here, we present an indirect gonioscopy based imaging probe with significantly improved visualization of structures in the ICA including TM region, compared to the currently available tools. Imaging quality of the developed system was tested in porcine samples. Improved direct high quality visualization of the TM region through this system can be used for Laser trabeculoplasty, which is a primary treatment of glaucoma. This system is expected to be used complementary to angle photography and gonioscopy.
Tang, Yi; Sorenson, Jeff; Lanspa, Michael; Grissom, Colin K; Mathews, V J; Brown, Samuel M
2017-06-17
Severe sepsis and septic shock are often lethal syndromes, in which the autonomic nervous system may fail to maintain adequate blood pressure. Heart rate variability has been associated with outcomes in sepsis. Whether systolic blood pressure (SBP) variability is associated with clinical outcomes in septic patients is unknown. The propose of this study is to determine whether variability in SBP correlates with vasopressor independence and mortality among septic patients. We prospectively studied patients with severe sepsis or septic shock, admitted to an intensive care unit (ICU) with an arterial catheter. We analyzed SBP variability on the first 5-min window immediately following ICU admission. We performed principal component analysis of multidimensional complexity, and used the first principal component (PC 1 ) as input for Firth logistic regression, controlling for mean systolic pressure (SBP) in the primary analyses, and Acute Physiology and Chronic Health Evaluation (APACHE) II score or NEE dose in the ancillary analyses. Prespecified outcomes were vasopressor independence at 24 h (primary), and 28-day mortality (secondary). We studied 51 patients, 51% of whom achieved vasopressor independence at 24 h. Ten percent died at 28 days. PC 1 represented 26% of the variance in complexity measures. PC 1 was not associated with vasopressor independence on Firth logistic regression (OR 1.04; 95% CI: 0.93-1.16; p = 0.54), but was associated with 28-day mortality (OR 1.16, 95% CI: 1.01-1.35, p = 0.040). Early SBP variability appears to be associated with 28-day mortality in patients with severe sepsis and septic shock.
Association between ascites and primary hyperfibrinolysis: A cohort study in 210 dogs.
Zoia, Andrea; Drigo, Michele; Simioni, Paolo; Caldin, Marco; Piek, Christine J
2017-05-01
Coagulation profiles were determined in 70 dogs with ascites, 70 healthy control dogs and 70 sick control dogs without ascites. Dogs with ascites were divided into four sub-groups based on the pathophysiology of fluid formation. Coagulation profile, serum C-reactive protein and frequency of discordant plasma fibrin-fibrinogen degradation products and D-dimer assay results, suggesting primary hyperfibrinolysis, were compared between groups. Within the ascites group, 10 samples of ascitic fluid were transudates due to decreased osmotic pressure, 18 were transudates due to increased hydrostatic pressure, 13 were exudates and 29 were haemorrhagic. Plasma fibrinogen concentrations were significantly lower in dogs with ascites compared to sick dogs without ascites. Activated partial thromboplastin time, prothrombin time, plasma concentrations of fibrin-fibrinogen degradation products and D-dimers, and frequency of primary hyperfibrinolysis, were significantly higher for dogs with ascites compared to both control groups. There was no significant difference in platelet count between groups. The frequency of primary hyperfibrinolysis was highest in dogs with transudative ascites due to increased hydrostatic pressure. Serum C-reactive protein was significantly higher in dogs with ascites compared to both control groups, and significantly and positively correlated with plasma D-dimers. In conclusion, dogs with ascites have an increased frequency of primary hyperfibrinolysis, especially with ascites secondary to increased hydrostatic pressure. The increased inflammation present in these dogs may have activated haemostasis in some cases, explaining the higher plasma D-dimers. Copyright © 2017 Elsevier Ltd. All rights reserved.
2003-06-06
KENNEDY SPACE CENTER, FLA. - An overview of the Space Station Processing Facility shows workstands and ISS elements. The most recent additions are the Japanese Experiment Module (JEM)’s pressurized module and the Italian-built Node 2. The pressurized module is the first element of the JEM, Japan’s primary contribution to the Space Station, to be delivered to KSC. It will enhance the unique research capabilities of the orbiting complex by providing an additional shirt-sleeve environment for astronauts to conduct science experiments. Node 2 will be installed on the end of the U.S. Lab and provides attach locations for the Japanese laboratory, European laboratory, the Centrifuge Accommodation Module and, later, Multipurpose Logistics Modules. It will provide the primary docking location for the Shuttle when a pressurized mating adapter is attached to Node 2. Installation of the module will complete the U.S. Core of the ISS.
2003-06-06
KENNEDY SPACE CENTER, FLA. - A view of the Space Station Processing Facility shows workstands and ISS elements. The most recent additions are the Japanese Experiment Module (JEM)’s pressurized module and the Italian-built Node 2. The pressurized module is the first element of the JEM, Japan’s primary contribution to the Space Station, to be delivered to KSC. It will enhance the unique research capabilities of the orbiting complex by providing an additional shirt-sleeve environment for astronauts to conduct science experiments. Node 2 will be installed on the end of the U.S. Lab and provides attach locations for the Japanese laboratory, European laboratory, the Centrifuge Accommodation Module and, later, Multipurpose Logistics Modules. It will provide the primary docking location for the Shuttle when a pressurized mating adapter is attached to Node 2. Installation of the module will complete the U.S. Core of the ISS.
Beddhu, Srinivasan; Chertow, Glenn M; Cheung, Alfred K; Cushman, William C; Rahman, Mahboob; Greene, Tom; Wei, Guo; Campbell, Ruth C; Conroy, Margaret; Freedman, Barry I; Haley, William; Horwitz, Edward; Kitzman, Dalane; Lash, James; Papademetriou, Vasilios; Pisoni, Roberto; Riessen, Erik; Rosendorff, Clive; Watnick, Suzanne G; Whittle, Jeffrey; Whelton, Paul K
2018-01-09
In individuals with a low diastolic blood pressure (DBP), the potential benefits or risks of intensive systolic blood pressure (SBP) lowering are unclear. SPRINT (Systolic Blood Pressure Intervention Trial) was a randomized controlled trial that compared the effects of intensive (target <120 mm Hg) and standard (target <140 mm Hg) SBP control in 9361 older adults with high blood pressure at increased risk of cardiovascular disease. The primary outcome was a composite of cardiovascular disease events. All-cause death and incident chronic kidney disease were secondary outcomes. This post hoc analysis examined whether the effects of the SBP intervention differed by baseline DBP. Mean baseline SBP and DBP were 139.7±15.6 and 78.1±11.9 mm Hg, respectively. Regardless of the randomized treatment, baseline DBP had a U-shaped association with the hazard of the primary cardiovascular disease outcome. However, the effects of the intensive SBP intervention on the primary outcome were not influenced by baseline DBP level ( P for interaction=0.83). The primary outcome hazard ratio for intensive versus standard treatment was 0.78 (95% confidence interval, 0.57-1.07) in the lowest DBP quintile (mean baseline DBP, 61±5 mm Hg) and 0.74 (95% confidence interval, 0.61-0.90) in the upper 4 DBP quintiles (mean baseline DBP, 82±9 mm Hg), with an interaction P value of 0.78. Results were similar for all-cause death and kidney events. Low baseline DBP was associated with increased risk of cardiovascular disease events, but there was no evidence that the benefit of the intensive SBP lowering differed by baseline DBP. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01206062. © 2017 American Heart Association, Inc.
Evaluation of a 40 to 1 scale model of a low pressure engine
NASA Technical Reports Server (NTRS)
Cooper, C. E., Jr.; Thoenes, J.
1972-01-01
An evaluation of a scale model of a low pressure rocket engine which is used for secondary injection studies was conducted. Specific objectives of the evaluation were to: (1) assess the test conditions required for full scale simulations; (2) recommend fluids to be used for both primary and secondary flows; and (3) recommend possible modifications to be made to the scale model and its test facility to achieve the highest possible degree of simulation. A discussion of the theoretical and empirical scaling laws which must be observed to apply scale model test data to full scale systems is included. A technique by which the side forces due to secondary injection can be analytically estimated is presented.
Maranger, Julie; Malcolm, Janine; Liddy, Clare; Izzi, Sheryl; Brez, Sharon; LaBrecque, Kerri; Taljaard, Monica; Reid, Robert; Keely, Erin; Ooi, Teik Chye
2013-01-01
The epidemic of diabetes has increased pressure on the whole spectrum of the healthcare system including specialist centres. The authors' own specialist centre at The Ottawa Hospital has 20,000 annual visits for diabetes, 80% of which are follow-up visits. Since it is a tertiary facility, managers, administrators and clinicians would like to increase their ability to see newly referred patients and decrease the number of follow-up visits. In order to discharge appropriate diabetes patients, the authors decided it was essential to strengthen the transition process to decrease both the pressure on the centre and the risk for discontinuity of diabetes care after discharge.
Bleed cycle propellant pumping in a gas-core nuclear rocket engine system
NASA Technical Reports Server (NTRS)
Kascak, A. F.; Easley, A. J.
1972-01-01
The performance of ideal and real staged primary propellant pumps and bleed-powered turbines was calculated for gas-core nuclear rocket engines over a range of operating pressures from 500 to 5000 atm. This study showed that for a required engine operating pressure of 1000 atm the pump work was about 0.8 hp/(lb/sec), the specific impulse penalty resulting from the turbine propellant bleed flow as about 10 percent; and the heat required to preheat the propellant was about 7.8 MN/(lb/sec). For a specific impulse above 2400 sec, there is an excess of energy available in the moderator due to the gamma and neutron heating that occurs there. Possible alternative pumping cycles are the Rankine or Brayton cycles.
Mc Hugh, Sheena; Marsden, Paul; Brennan, Carmel; Murphy, Katie; Croarkin, Celine; Moran, Joe; Harkins, Velma; Perry, Ivan J
2011-12-28
The aim of the present study was to assess the performance of three primary care-led initiatives providing structured care to patients with Type 2 diabetes in Ireland, a country with minimal incentives to promote the quality of care. Data, from three primary care initiatives, were available for 3010 adult patients with Type 2 diabetes. Results were benchmarked against the national guidelines for the management of Type 2 diabetes in the community and results from the National Diabetes Audit (NDA) for England (2008/2009) and the Scottish Diabetes Survey (2009). The recording of clinical processes of care was similar to results in the UK however the recording of lifestyle factors was markedly lower. Recording of HbA1c, blood pressure and lipids exceeded 85%. Recording of retinopathy screening (71%) was also comparable to England (77%) and Scotland (90%). Only 63% of patients had smoking status recorded compared to 99% in Scotland while 70% had BMI recorded compared to 89% in England. A similar proportion of patients in this initiative and the UK achieved clinical targets. Thirty-five percent of patients achieved a target HbA1c of < 6.5% (< 48 mmol/mol) compared to 25% in England. Applying the NICE target for blood pressure (≤ 140/80 mmHg), 54% of patients reached this target comparable to 60% in England. Slightly less patients were categorised as obese (> 30 kg/m²) in Ireland (50%, n = 1060) compared to Scotland (54%). This study has demonstrated what can be achieved by proactive and interested health professionals in the absence of national infrastructure to support high quality diabetes care. The quality of primary care-led diabetes management in the three initiatives studied appears broadly consistent with results from the UK with the exception of recording lifestyle factors. The challenge facing health systems is to establish quality assurance a responsibility for all health care professionals rather than the subject of special interest for a few.
Bases of the Mantle-Carbonatite Conception of Diamond Genesis
NASA Astrophysics Data System (ADS)
Litvin, Yuriy; Spivak, Anna; Kuzyura, Anastasia
2016-04-01
In the mantle-carbonatite conception of diamond genesis, the results of physic-chemical experiments are coordinated with the data of analytic mineralogy of primary inclusions in natural diamonds. Generalization of the solutions of principal genetic problems constitutes the bases of the conception. The solutions are following: (1) it is grounded that diamond-parental melts of the upper mantle have peridotite/eclogite - carbonatite - carbon compositions, of the transition zone - (wadsleite↔ringwoodite) - majorite - stishovite - carbonatite - carbon compositions, and of the lower mantle - periclase/wustite - bridgmanite - Ca-perovskite -stishovite - carbonatite - carbon compositions; (2) a construction of generalized diagrams for the diamond-parental media, which reveal changeable compositions of the growth melts of diamonds and associated phases, their genetic relations to the mantle substance, and classification connections of the primary inclusions in natural diamonds; (3) experimental equilibrium phase diagrams of syngenesis of diamonds and primary inclusions, which characterize the nucleation and growth conditions of diamonds and a capture of paragenetic and xenogenetic minerals by the growing diamonds; (4) a determination of the phase diagrams of diamonds and inclusions syngenesis under the regime of fractional crystallization, which discover the regularities of ultrabasic-basic evolution and paragenesis transitions in the diamond-forming systems of the upper and lower mantle. The evidence of the physic-chemically united mode of diamond genesis at the mantle depths with different mineralogy is obtained. References. Litvin Yu.A. (2007). High-pressure mineralogy of diamond genesis. In: Advances in High-Pressure Mineralogy (edited by Eiji Ohtani), Geological Society of America Special paper 421, 83-103. Litvin Yu.A. (2012). Experimental study of physic-chemical conditions of natural diamond formation on an example of the eclogite-carbonatite-sulphide-diamond system. Geology of Ore Deposits. 54(6), 523-539. Litvin Yu.A., Spivak A.V., Solopova N.A., Dubrovinsky L.S. (2014). On origin of lower-mantle diamonds and their primary inclusions. Physics of the Earth and Planetary Interiors, 228 (The Liebermann Volume), 176-185. http://dx.doi.org/10.1016/j/pepi/2013.12.007
Therapeutic Options for Controlling Fluids in the Visual System
NASA Technical Reports Server (NTRS)
Curry, Kristina M.; Wotring, Virginia E.
2014-01-01
Visual Impairment/Intracranial Pressure (VIIP) is a newly recognized risk at NASA. The VIIP project examines the effect of long-term exposure to microgravity on vision of crewmembers before and after they return to Earth. Diamox (acetazolamide) is a medication which is used to decrease intraocular pressure; however, it carries a 3% risk of kidney stones. Astronauts are at a higher risk of kidney stones during spaceflight and the use Diamox would only increase the risk; therefore alternative therapies were investigated. Histamine 2 (H2) antagonist acid blockers such as cimetidine, ranitidine, famotidine and nizatidine are typically used to relieve the symptoms of gastroesophageal reflux disease (GERD). H2 receptors have been found in the human visual system, which has led to research on the use of H2 antagonist blockers to control fluid production in the human eye. Another potential therapeutic strategy is targeted at aquaporins, which are water channels that help maintain fluid homeostasis. Aquaporin antagonists are also known to affect intracranial pressure which can in turn alter intraocular pressure. Studies on aquaporin antagonists suggest high potential for effective treatment. The primary objective of this investigation is to review existing research on alternate medications or therapy to significantly reduce intracranial and intraocular pressure. A literature review was conducted. Even though we do not have all the answers quite yet, a considerable amount of information was discovered, and findings were narrowed, which should allow for more conclusive answers to be found in the near future.
Preanalytical Nonconformity Management Regarding Primary Tube Mixing in Brazil.
Lima-Oliveira, Gabriel; Cesare Guidi, Gian; Guimaraes, Andre Valpassos Pacifici; Abol Correa, Jose; Lippi, Giuseppe
2017-01-01
The multifaceted clinical laboratory process is divided in three essential phases: the preanalytical, analytical and postanalytical phase. Problems emerging from the preanalytical phase are responsible for more than 60% of laboratory errors. This report is aimed at highlighting and discussing nonconformity (e.g., nonstandardized procedures) in primary blood tube mixing immediately after blood collection by venipuncture with evacuated tube systems. From January 2015 to December 2015, fifty different laboratory quality managers from Brazil were contacted to request their internal audit reports on nonconformity regarding primary blood tube mixing immediately after blood collection by venipuncture performed using evacuated tube systems. A minority of internal audits (i.e., 4%) concluded that evacuated blood tubes were not accurately mixed after collection, whereas more than half of them reported that evacuated blood tubes were vigorously mixed immediately after collection, thus magnifying the risk of producing spurious hemolysis. Despite the vast ma jority of centers declaring that evacuated blood tubes were mixed gently and carefully, the overall number of inversions was found to be different from that recommended by the manufacturer. Since the turbulence generated by the standard vacuum pressure inside the primary evacuated tubes seems to be sufficient for providing solubilization, mixing and stabilization between additives and blood during venipuncture, avoidance of primary tube mixing probably does not introduce a major bias in tests results and may not be considered a nonconformity during audits for accreditation.
Direct observations of evolving subglacial drainage beneath the Greenland Ice Sheet.
Andrews, Lauren C; Catania, Ginny A; Hoffman, Matthew J; Gulley, Jason D; Lüthi, Martin P; Ryser, Claudia; Hawley, Robert L; Neumann, Thomas A
2014-10-02
Seasonal acceleration of the Greenland Ice Sheet is influenced by the dynamic response of the subglacial hydrologic system to variability in meltwater delivery to the bed via crevasses and moulins (vertical conduits connecting supraglacial water to the bed of the ice sheet). As the melt season progresses, the subglacial hydrologic system drains supraglacial meltwater more efficiently, decreasing basal water pressure and moderating the ice velocity response to surface melting. However, limited direct observations of subglacial water pressure mean that the spatiotemporal evolution of the subglacial hydrologic system remains poorly understood. Here we show that ice velocity is well correlated with moulin hydraulic head but is out of phase with that of nearby (0.3-2 kilometres away) boreholes, indicating that moulins connect to an efficient, channelized component of the subglacial hydrologic system, which exerts the primary control on diurnal and multi-day changes in ice velocity. Our simultaneous measurements of moulin and borehole hydraulic head and ice velocity in the Paakitsoq region of western Greenland show that decreasing trends in ice velocity during the latter part of the melt season cannot be explained by changes in the ability of moulin-connected channels to convey supraglacial melt. Instead, these observations suggest that decreasing late-season ice velocity may be caused by changes in connectivity in unchannelized regions of the subglacial hydrologic system. Understanding this spatiotemporal variability in subglacial pressures is increasingly important because melt-season dynamics affect ice velocity beyond the conclusion of the melt season.
Health system challenges of NCDs in Tunisia.
Ben Romdhane, Habiba; Tlili, Faten; Skhiri, Afef; Zaman, Shahaduz; Phillimore, Peter
2015-01-01
The objective of this study was to present a qualitative 'situation analysis' of the healthcare system in Tunisia, as it applies to management of cardiovascular disease (CVD) and diabetes. A primary concern was the institutional capacity to manage non-communicable diseases (NCDs). Research took place during 2010 (analysis of official documents, semi-structured interviews with key informants, and case studies in four clinics). Walt and Gilson's framework (1994) for policy analysis was used: content, actors, context, and process. Problems of integration and coordination have compounded funding pressures. Despite its importance in Tunisian healthcare, primary health is ill-equipped to manage NCDs. With limited funds, and no referral or health information system, staff morale in the public sector was low. Private healthcare has been the main development filling the void. This study highlights major gaps in the implementation of a comprehensive approach to NCDs, which is an urgent task across the region. In strategic planning, research on the health system is vital; but the capacity within Ministries of Health to use research has first to be built, with a commitment to grounding policy change in evidence.
Direct probing of chromatography columns by laser-induced fluorescence
NASA Astrophysics Data System (ADS)
McGuffin, V. L.
1992-12-01
This report summarizes the progress and accomplishments of this research project from 1 Sep. 1989 to 28 Feb. 1993. During this period, we have accomplished all of the primary scientific objectives of the research proposal: (1) constructed and evaluated a laser-induced fluorescence detection system that allows direct examination of the chromatographic column, (2) examined nonequilibrium processes that occur upon solute injection and elution, (3) examined solute retention in liquid chromatography as a function of temperature and pressure, (4) examined solute zone dispersion in liquid chromatography as a function of temperature and pressure, and (5) developed appropriate theoretical models to describe these phenomena. In each of these studies, substantial knowledge has been gained of the fundamental processes that are responsible for chromatographic separations. In addition to these primary research objectives, we have made significant progress in three related areas: (1) examined pyrene as a fluorescent polarity probe in supercritical fluids and liquids as a function of temperature and pressure, (2) developed methods for the class-selective identification of polynuclear aromatic hydrocarbons in coal-derived fluids by microcolumn liquid chromatography with fluorescence quenching detection, and (3) developed methods for the determination of saturated and unsaturated (including omega-3) fatty acids in fish oil extracts by microcolumn liquid chromatography with laser-induced fluorescence detection. In these studies, the advanced separation and detection techniques developed in our laboratory are applied to practical problems of environmental and biomedical significance.
Effect of aminophylline on hindlimb blood flow autoregulation during increased metabolism in dogs.
Metting, P J; Weldy, D L; Ronau, T F; Britton, S L
1986-06-01
The contribution of adenosine to hindlimb blood flow autoregulation during treadmill exercise or the administration of 2,4-dinitrophenol (DNP) was evaluated in 9 conscious dogs by determining hindlimb vascular bed pressure-flow relationships in the presence and absence of the adenosine receptor site antagonist, aminophylline. Hindlimb pressure-flow relationships were obtained by measuring blood flow during stepwise reductions in perfusion pressure produced with an occlusion cuff located distal to a flow probe on the external iliac artery. The efficiency of autoregulation was quantitated by calculating the closed-loop gain of flow regulation (Gc) at each pressure decrement utilizing the equation Gc = 1 - (% delta flow/% delta pressure). A Gc of one represents perfect autoregulation of flow, and a Gc of zero is indicative of a rigid system. During exercise, Gc averaged 0.44 +/- 0.07. Aminophylline reduced the Gc during exercise to -0.07 +/- 0.06 (P less than 0.05). During DNP administration, Gc averaged 0.54 +/- 0.09 and declined to -0.09 +/- 0.10 in the presence of aminophylline (P less than 0.05). These results support the hypothesis that adenosine is a primary mediator of hindlimb blood flow autoregulation during conditions that increase hindlimb metabolism.
Cavitation Inside High-Pressure Optically Transparent Fuel Injector Nozzles
NASA Astrophysics Data System (ADS)
Falgout, Z.; Linne, M.
2015-12-01
Nozzle-orifice flow and cavitation have an important effect on primary breakup of sprays. For this reason, a number of studies in recent years have used injectors with optically transparent nozzles so that orifice flow cavitation can be examined directly. Many of these studies use injection pressures scaled down from realistic injection pressures used in modern fuel injectors, and so the geometry must be scaled up so that the Reynolds number can be matched with the industrial applications of interest. A relatively small number of studies have shown results at or near the injection pressures used in real systems. Unfortunately, neither the specifics of the design of the optical nozzle nor the design methodology used is explained in detail in these papers. Here, a methodology demonstrating how to prevent failure of a finished design made from commonly used optically transparent materials will be explained in detail, and a description of a new design for transparent nozzles which minimizes size and cost will be shown. The design methodology combines Finite Element Analysis with relevant materials science to evaluate the potential for failure of the finished assembly. Finally, test results imaging a cavitating flow at elevated pressures are presented.
Dervan, Edward; Lee, Edward; Giubilato, Antonio; Khanam, Tina; Maghsoudlou, Panayiotis; Morgan, William H
2017-11-01
This study provides results of a treatment option for patients with failed primary glaucoma drainage device. The study aimed to describe and evaluate the long-term intraocular pressure control and complications of a new technique joining a second glaucoma drainage device directly to an existing glaucoma drainage device termed 'piggyback drainage'. This is a retrospective, interventional cohort study. Eighteen eyes of 17 patients who underwent piggyback drainage between 2004 and 2013 inclusive have been studied. All patients had prior glaucoma drainage device with uncontrolled intraocular pressure. The piggyback technique involved suturing a Baerveldt (250 or 350 mm) or Molteno3 glaucoma drainage device to an unused scleral quadrant and connecting the silicone tube to the primary plate bleb. Failure of intraocular pressure control defined as an intraocular pressure greater than 21 mmHg on maximal therapy on two separate occasions or further intervention to control intraocular pressure. The intraocular pressure was controlled in seven eyes (39%) at last follow-up with a mean follow-up time of 74.2 months. The mean preoperative intraocular pressure was 27.1 mmHg (95% confidence interval 23.8-30.3) compared with 18.4 mmHg (95% confidence interval 13.9-22.8) at last follow-up. The mean time to failure was 57.1 months (95% confidence interval 32.2-82), and the mean time to further surgery was 72.3 months (95% confidence interval 49.9-94.7). Lower preoperative intraocular pressure was associated with longer duration of intraocular pressure control (P = 0.048). If the intraocular pressure was controlled over 2 years, it continued to be controlled over the long term. Two eyes (11%) experienced corneal decompensation. Piggyback drainage represents a viable surgical alternative for the treatment of patients with severe glaucoma with failing primary glaucoma drainage device, particularly in those at high risk of corneal decompensation. © 2017 Royal Australian and New Zealand College of Ophthalmologists.
Review of battery powered embedded systems design for mission-critical low-power applications
NASA Astrophysics Data System (ADS)
Malewski, Matthew; Cowell, David M. J.; Freear, Steven
2018-06-01
The applications and uses of embedded systems is increasingly pervasive. Mission and safety critical systems relying on embedded systems pose specific challenges. Embedded systems is a multi-disciplinary domain, involving both hardware and software. Systems need to be designed in a holistic manner so that they are able to provide the desired reliability and minimise unnecessary complexity. The large problem landscape means that there is no one solution that fits all applications of embedded systems. With the primary focus of these mission and safety critical systems being functionality and reliability, there can be conflicts with business needs, and this can introduce pressures to reduce cost at the expense of reliability and functionality. This paper examines the challenges faced by battery powered systems, and then explores at more general problems, and several real-world embedded systems.
Amponsah-Tawaih, Kwesi; Adu, Michael Appiah
2016-12-01
safety and healthy working environment has received numerous research attention over the years. Majority of these researches seem to have been conducted in the construction industry, with little attention in the health sector. Nonetheless, there are couple of studies conducted in Africa that suggest pressure in hospitals. Therefore the aim of the study was to examine how pressure influence safety behavior in the hospitals. With reference to the relevance of safety behavior in primary health care delivery, there was the need for the study. Data was obtained from 422 public hospital employees. Respondents were assured that all information would be kept confidential to increase the response rate and acquire more accurate information. Collection of questionnaires from participants took four weeks (20 working days), after which the data was analyzed. The result of the study showed that work pressure correlated negatively with safety behavior. General safety climate significantly correlated positively with safety behavior and negatively with work pressure, although the effect size for the latter was smaller. Hierarchical regression analysis showed management commitment to safety to moderate the relationship between work pressure and safety behavior. When employees perceive safety communication, safety systems and training to be positive, they seem to comply with safety rules and procedures than voluntarily participate in safety activities.
Effect of pressure on the α relaxation in glycerol and xylitol
NASA Astrophysics Data System (ADS)
Paluch, M.; Casalini, R.; Hensel-Bielowka, S.; Roland, C. M.
2002-06-01
The effect of pressure on the dielectric relaxation of two polyhydroxy alcohols is examined by analysis of existing data on glycerol, together with new measurements on xylitol. The fragility, or Tg-normalized temperature dependence, changes with pressure for low pressures, but becomes invariant above 1 GPa. When compared at temperatures for which the α-relaxation times are equal, there is no effect of pressure (<1 GPa) on the shape of the α dispersion at higher temperatures. However, nearer Tg, pressure broadens the α peak, consistent with the expected correlation of fragility with the breadth of the relaxation function. We also observe that the α-relaxation peaks for both glycerol and xylitol show an excess intensity at higher frequencies. For xylitol, unlike for glycerol, at lower temperatures this wing disjoins to form a separate peak. For both glass formers, elevated pressure causes the excess wing to become more separated from the peak maximum; that is, the properties of the primary and excess intensities are not correlated. This implies that the excess wing in glycerol is also a distinct secondary process, although it cannot be resolved from the primary peak.
Laser-Induced Fluorescence and Synthetic Jet Fuel Analysis in the Ultra Compact Combustor
2009-12-01
In the primary zone, high- temperature, high-pressure air enters from the compressor and flows around fuel injectors spraying atomized liquid -droplet...chemical reaction in which synthesis gas , a mixture of carbon monoxide and hydrogen, is converted into liquid hydrocarbons of various forms. The most...the fuel lines needed to be rebuilt due to a recent COAL lab renovation. The liquid fuel system had not been used for nearly two years so some
Accumulation and subsequent utilization of waste heat
NASA Astrophysics Data System (ADS)
Koloničný, Jan; Richter, Aleš; Pavloková, Petra
2016-06-01
This article aims to introduce a special way of heat accumulation and primary operating characteristics. It is the unique way in which the waste heat from flue gas of biogas cogeneration station is stored in the system of storage tanks, into the heat transfer oil. Heat is subsequently transformed into water, from which is generated the low-pressure steam. Steam, at the time of peak electricity needs, spins the special designed turbine generator and produces electrical energy.
2004-02-10
KENNEDY SPACE CENTER, FLA. - Workers watch as the Multi-Purpose Logistics Module Raffaello is lowered toward a work stand in the Space Station Processing Facility. Raffaello is the second MPLM built by the Italian Space Agency, serving as a reusable logistics carrier and primary delivery system to resupply and return station cargo requiring a pressurized environment. It has been moved across the floor to allow the third MPLM, Donatello, to be brought in for routine testing. Donatello has been stored in the Operations and Checkout Building. This is the first time all three MPLMs are in the SSPF; the other one is the Leonardo. Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-10
KENNEDY SPACE CENTER, FLA. - The Multi-Purpose Logistics Module Raffaello is lifted from its stand in the Space Station Processing Facility to move to another work stand. Raffaello is the second MPLM built by the Italian Space Agency, serving as a reusable logistics carrier and primary delivery system to resupply and return station cargo requiring a pressurized environment. It is being moved to allow the third MPLM, Donatello, to be brought in for routine testing. Donatello has been stored in the Operations and Checkout Building. This is the first time all three MPLMs are in the SSPF; the other one is the Leonardo. Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-10
KENNEDY SPACE CENTER, FLA. - A worker on the floor watches as the Multi-Purpose Logistics Module Raffaello moves toward another work stand in the Space Station Processing Facility. Raffaello is the second MPLM built by the Italian Space Agency, serving as a reusable logistics carrier and primary delivery system to resupply and return station cargo requiring a pressurized environment. It has been moved across the floor to allow the third MPLM, Donatello, to be brought in for routine testing. Donatello has been stored in the Operations and Checkout Building. This is the first time all three MPLMs are in the SSPF; the other one is the Leonardo. Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-10
KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, the Multi-Purpose Logistics Module Raffaello glides above the floor as it moves to another stand on the other side. Raffaello is the second MPLM built by the Italian Space Agency, serving as a reusable logistics carrier and primary delivery system to resupply and return station cargo requiring a pressurized environment. It is being moved to allow the third MPLM, Donatello, to be brought in for routine testing. Donatello has been stored in the Operations and Checkout Building. This is the first time all three MPLMs are in the SSPF; the other one is the Leonardo. Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-10
KENNEDY SPACE CENTER, FLA. - An overhead crane is attached to the Multi-Purpose Logistics Module Raffaello in order to move it to another work stand in the Space Station Processing Facility. Raffaello is the second MPLM built by the Italian Space Agency, serving as a reusable logistics carrier and primary delivery system to resupply and return station cargo requiring a pressurized environment. It is being moved to allow the third MPLM, Donatello, to be brought in for routine testing. Donatello has been stored in the Operations and Checkout Building. This is the first time all three MPLMs are in the SSPF; the other one is the Leonardo. Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
2004-02-10
KENNEDY SPACE CENTER, FLA. - Workers in the Space Station Processing Facility prepare to release the overhead crane from the Multi-Purpose Logistics Module Raffaello now secure on a new work stand. Raffaello is the second MPLM built by the Italian Space Agency, serving as a reusable logistics carrier and primary delivery system to resupply and return station cargo requiring a pressurized environment. It has been moved to allow the third MPLM, Donatello, to be brought in for routine testing. Donatello has been stored in the Operations and Checkout Building. This is the first time all three MPLMs are in the SSPF; the other one is the Leonardo. Raffaello is scheduled to fly on Space Shuttle Atlantis on mission STS-114.
NASA Technical Reports Server (NTRS)
Green, Robert S.; Carson, George T., Jr.
1987-01-01
An investigation was conducted in the Langley 16-Foot Transonic Tunnel at static conditions to measure the pressure distributions inside a nonaxisymmetric nozzle with simultaneous partial thrust reversing (50-percent deployment) and thrust vectoring of the primary (forward-thrust) nozzle flow. Geometric forward-thrust-vector angles of 0 and 15 deg. were tested. Test data were obtained at static conditions while nozzle pressure ratio was varied from 2.0 to 4.0. Results indicate that, unlike the 0 deg. vector angle nozzle, a complicated, asymmetric exhaust flow pattern exists in the primary-flow exhaust duct of the 15 deg. vectored nozzle.
Analysis and testing of high entrainment single nozzle jet pumps with variable mixing tubes
NASA Technical Reports Server (NTRS)
Hickman, K. E.; Hill, P. G.; Gilbert, G. B.
1972-01-01
An analytical model was developed to predict the performance characteristics of axisymmetric single-nozzle jet pumps with variable area mixing tubes. The primary flow may be subsonic or supersonic. The computer program uses integral techniques to calculate the velocity profiles and the wall static pressures that result from the mixing of the supersonic primary jet and the subsonic secondary flow. An experimental program was conducted to measure mixing tube wall static pressure variations, velocity profiles, and temperature profiles in a variable area mixing tube with a supersonic primary jet. Static pressure variations were measured at four different secondary flow rates. These test results were used to evaluate the analytical model. The analytical results compared well to the experimental data. Therefore, the analysis is believed to be ready for use to relate jet pump performance characteristics to mixing tube design.
2007-03-13
KENNEDY SPACE CENTER, FLA. -- A flat bed truck hauls the container with the Experiment Logistics Module Pressurized Section inside away from the Trident wharf. The logistics module is part of the Japanese Experiment Module. The logistics module is being transported to the Space Station Processing Facility at NASA's Kennedy Space Center. The Japanese Experiment Module is composed of three segments and is known as Kibo, which means "hope" in Japanese. Kibo consists of six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007. Photo credit: NASA/Kim Shiflett
2007-03-13
KENNEDY SPACE CENTER, FLA. -- At the Trident wharf, workers help guide the container with the Experiment Logistics Module Pressurized Section inside toward the dock. The logistics module is part of the Japanese Experiment Module. The logistics module will be transported to the Space Station Processing Facility at NASA's Kennedy Space Center. The Japanese Experiment Module is composed of three segments and is known as Kibo, which means "hope" in Japanese. Kibo consists of six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007. Photo credit: NASA/Kim Shiflett
2007-03-12
KENNEDY SPACE CENTER, FLA. -- The ship carrying the Experiment Logistics Module Pressurized Section for the Japanese Experiment Module arrives at the Trident wharf after departing from Yokohama, Japan, Feb. 7. The logistics module will be offloaded and transported to the Space Station Processing Facility at NASA's Kennedy Space Center. The Japanese Experiment Module is composed of three segments and is known as Kibo, which means "hope" in Japanese. Kibo consists of six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007. Photo credit: NASA/Kim Shiflett
2007-03-12
KENNEDY SPACE CENTER, FLA. -- The ship carrying the Experiment Logistics Module Pressurized Section for the Japanese Experiment Module arrives at the Trident wharf after departing from Yokohama, Japan, Feb. 7. The logistics module will be offloaded and transported to the Space Station Processing Facility at NASA's Kennedy Space Center. The Japanese Experiment Module is composed of three segments and is known as Kibo, which means "hope" in Japanese. Kibo consists of six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007. Photo credit: NASA/Kim Shiflett
2007-03-12
KENNEDY SPACE CENTER, FLA. -- The ship carrying the Experiment Logistics Module Pressurized Section for the Japanese Experiment Module arrives at the Trident wharf after departing from Yokohama, Japan, Feb. 7. The logistics module will be offloaded and transported to the Space Station Processing Facility at NASA's Kennedy Space Center. The Japanese Experiment Module is composed of three segments and is known as Kibo, which means "hope" in Japanese. Kibo consists of six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007. Photo credit: NASA/Kim Shiflett
2007-03-12
KENNEDY SPACE CENTER, FLA. -- The ship carrying the Experiment Logistics Module Pressurized Section for the Japanese Experiment Module is tied up at the Trident wharf after departing from Yokohama, Japan, Feb. 7. The logistics module will be offloaded and transported to the Space Station Processing Facility at NASA's Kennedy Space Center. The Japanese Experiment Module is composed of three segments and is known as Kibo, which means "hope" in Japanese. Kibo consists of six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007. Photo credit: NASA/Kim Shiflett
Modification of a liquid hydrogen tank for integrated refrigeration and storage
NASA Astrophysics Data System (ADS)
Swanger, A. M.; Jumper, K. M.; Fesmire, J. E.; Notardonato, W. U.
2015-12-01
The modification and outfitting of a 125,000-liter liquid hydrogen tank was performed to provide integrated refrigeration and storage capability. These functions include zero boil-off, liquefaction, and densification and therefore require provisions for sub-atmospheric tank pressures within the vacuum-jacketed, multilayer insulated tank. The primary structural modification was to add stiffening rings inside the inner vessel. The internal stiffening rings were designed, built, and installed per the ASME Boiler and Pressure Vessel Code, Section VIII, to prevent collapse in the case of vacuum jacket failure in combination with sub-atmospheric pressure within the tank. For the integrated refrigeration loop, a modular, skeleton-type heat exchanger, with refrigerant temperature instrumentation, was constructed using the stiffening rings as supports. To support the system thermal performance testing, three custom temperature rakes were designed and installed along the 21-meter length of the tank, once again using rings as supports. The temperature rakes included a total of 20 silicon diode temperature sensors mounted both vertically and radially to map the bulk liquid temperature within the tank. The tank modifications were successful and the system is now operational for the research and development of integrated refrigeration technology.
Microfluidic strategy to investigate dynamics of small blood vessel function
NASA Astrophysics Data System (ADS)
Yasotharan, Sanjesh; Bolz, Steffen-Sebastian; Guenther, Axel
2010-11-01
Resistance arteries (RAs, 30-300 microns in diameter) that are located within the terminal part of the vascular tree regulate the laminar perfusion of tissue with blood, via the peripheral vascular resistance, and hence controls the systemic blood pressure. The structure of RAs is adapted to actively controlling flow resistance by dynamically changing their diameter, which is non-linearly dependent on the temporal variation of the transmural pressure, perfusion flow rate and spatiotemporal changes in the chemical environment. Increases in systemic blood pressure (hypertension) resulting from pathologic changes in the RA response represent the primary risk factor for cardiovascular diseases. We use a microfluidic strategy to investigate small blood vessels by quantifying structural variations within the arterial wall, RA outer contour and diameter over time. First, we document the artery response to vasomotor drugs that were homogeneously applied at step-wise increasing concentration. Second, we investigate the response in the presence of well-defined axial and circumferential heterogeneities. Artery per- and superfusion is discussed based on microscale PIV measurements of the fluid velocity on both sides of the arterial wall. Structural changes in the arterial wall are quantified using cross-correlation and proper orthogonal decomposition analyses of bright-field micrographs.
NASA Technical Reports Server (NTRS)
Mennell, R. C.; Soard, T.
1974-01-01
Experimental aerodynamic investigations were conducted on a 0.0405 scale representation of the -89B space shuttle orbiter in the 7.75 x 11.00 foot low speed wind tunnel during the time period September 4 - 14, 1973. The primary test objective was to optimize the air breathing propulsion system nacelle cowl-inlet design and to determine the aerodynamic effects of this design on the orbiter stability and control characteristics. Nacelle cowl-inlet optimization was determined from total pressure - static pressure measurements obtained from pressure rakes located in the left hand nacelle pod at the engine face station. After the optimum cow-inlet design, consisting of a 7 deg cowl lip angle, short cowl, 7 deg short diverter, and a nacelle toe-in angle of 5 deg was selected, the aerodynamic effects of various locations of this design were investigated. The 3 pod - 6 Nacelle configuration was tested both underwing and overwing in three different longitudinal locations. Orbiter control effectiveness, both with and without Nacelles, was investigated at elevon deflections of 0 deg, -10 deg and +15 deg and at aileron deflections of 0 deg and +10 deg about 0 deg elevon.
Burkhart, Lisa; Sohn, Min-Woong; Jordan, Neil; Tarlov, Elizabeth; Gampetro, Pamela; LaVela, Sherri L
2016-01-01
The Veterans Health Administration piloted patient-centered care (PCC) innovations beginning in 2010 to improve patient and provider experience and environment in ambulatory care. We use secondary data to look at longitudinal trends, evaluate system redesign, and identify areas for further quality improvement. This was a retrospective, observational study using existing secondary data from multiple US Department of Veteran Affairs sources to evaluate changes in veteran and facility outcomes associated with PCC innovations at 2 innovation and matched comparison sites between FY 2008-2010 (pre-PCC innovations) and FY 2011-2012 (post-PCC innovations). Outcomes included access to primary care providers (PCPs); primary, specialty, and emergency care use; and clinical indicators for chronic disease. Longitudinal trends revealed a different story at each site. One site demonstrated better PCP access, decrease in emergency and primary care use, increase in specialty care use, and improvement in diabetic glucose control. The other site demonstrated a decrease in PCP access and primary care use, no change in specialty care use, and an increase in diastolic blood pressure in relation to the comparison site. Secondary data analysis can reveal longitudinal trends associated with system changes, thereby informing program evaluation and identifying opportunities for quality improvement.
Membrane-based systems for carbon capture and hydrogen purification
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berchtold, Kathryn A
2010-11-24
This presentation describes the activities being conducted at Los Alamos National Laboratory to develop carbon capture technologies for power systems. This work is aimed at continued development and demonstration of a membrane based pre- and post-combustion carbon capture technology and separation schemes. Our primary work entails the development and demonstration of an innovative membrane technology for pre-combustion capture of carbon dioxide that operates over a broad range of conditions relevant to the power industry while meeting the US DOE's Carbon Sequestration Program goals of 90% CO{sub 2} capture at less than a 10% increase in the cost of energy services.more » Separating and capturing carbon dioxide from mixed gas streams is a first and critical step in carbon sequestration. To be technically and economically viable, a successful separation method must be applicable to industrially relevant gas streams at realistic temperatures and pressures as well as be compatible with large gas volumes. Our project team is developing polymer membranes based on polybenzimidazole (PBI) chemistries that can purify hydrogen and capture CO{sub 2} at industrially relevant temperatures. Our primary objectives are to develop and demonstrate polymer-based membrane chemistries, structures, deployment platforms, and sealing technologies that achieve the critical combination of high selectivity, high permeability, chemical stability, and mechanical stability all at elevated temperatures (> 150 C) and packaged in a scalable, economically viable, high area density system amenable to incorporation into an advanced Integrated Gasification Combined-Cycle (IGCC) plant for pre-combustion CO{sub 2} capture. Stability requirements are focused on tolerance to the primary synthesis gas components and impurities at various locations in the IGCC process. Since the process stream compositions and conditions (temperature and pressure) vary throughout the IGCC process, the project is focused on the optimization of a technology that could be positioned upstream or downstream of one or more of the water-gas-shift reactors (WGSRs) or integrated with a WGSR.« less
Effective Use of Weld Metal Yield Strength for HY-Steels
1983-01-01
Boiler and Pressure Vessel Code The ASME Boiler and Pressure Vessel Code (B&PV Code) is divided...As noted earlier, the ASME Boiler and Pressure Vessel Code makes only one exception to its overall philosophy of matching weld-metal strength and...material where toughness is of primary importance. REFERENCES American Society of Mechanical Engineers, Boiler and Pressure Vessel
Martínez, M A; Aguirre, A; Sánchez, M; Nevado, A; Laguna, I; Torre, A; Manuel, E; Villar, C; García-Puig, J
1999-12-11
In the present study we evaluated the influence of the observer's status--physician or nurse--on blood pressure levels and the relationship among clinic blood pressure measurement with ambulatory blood pressure and left ventricle mass. Cross sectional study performed in seven primary care centers. Participating physicians and nurses were trained for blood pressure measurement prior to the study and subsequently retrained at 3 month intervals during the study. Patients included in the study were 122 subjects with mild to moderate hypertension who underwent the following study protocol: a) measurement of clinic blood pressure by physician and nurse, in an independent fashion, on 3 visits; b) clinic-epidemiologic questionnaire; c) conventional hematological and biochemical study; d) electrocardiogram; e) 24-hour ambulatory blood pressure monitoring, f) M-mode and Doppler echocardiography (only in 58 subjects). Nurse-measured blood pressure levels were higher than those determined by physicians (mean differences: 3.9 [6.7] mmHg in systolic blood pressure and 2.6 [5.4] mmHg in diastolic blood pressure). The blood pressure level differences between the two observers were higher in female patients and subjects with low educational level, independently of the observer's gender. Nurse-measured blood pressure was more closely related to ambulatory blood pressure and left ventricle mass than physician-measured blood pressure. Nurse-measured blood pressure levels are lower than those determined by physicians and more closely related to ambulatory blood pressure and left ventricle mass than physician-measured blood pressure. These data support that nurses, instead of doctors, should routinely measure blood pressure in primary care centers.
Mourtzinis, Georgios; Ebrahimi, Ahmad; Gustafsson, Helena; Johannsson, Gudmundur; Manhem, Karin
2017-11-01
Atrial fibrillation seems to be overrepresented among patients with primary aldosteronism. The aim of this study was to determine the usefulness of aldosterone to renin ratio as a screening instrument for primary aldosteronism in an atrial fibrillation population with relatively low cardiovascular risk profile. A total of 149 patients <65 years and with history of AF were screened for primary aldosteronism using aldosterone to renin ratio. Pathologically increased aldosterone to renin ratio (>65 pmol/mIU) was found in 15 participants (10.1%). Further investigation of the positive screened participants and confirmatory saline infusion test resulted in a diagnosis of primary aldosteronism in four individuals out of 149 (2.6%). Three out of the four individuals with primary aldosteronism had previously been diagnosed with hypertension, but only one out of the four had uncontrolled blood pressure, that is, >140/90 mmHg. All participants had normal potassium levels. Individuals with increased aldosterone to renin ratio had significantly higher mean systolic and diastolic blood pressure in comparison to participants with normal aldosterone to renin ratio (136 vs. 126 mmHg, p=0.02 and 84 vs. 78 mmHg, p=0.02). These findings suggest that assessment of aldosterone to renin ratio can be useful for identification of underlying primary aldosteronism in patients with diagnosed atrial fibrillation and hypertension in spite of well controlled blood pressure and normokalemia. © Georg Thieme Verlag KG Stuttgart · New York.
de Boer, Anna W; de Mutsert, Renée; den Heijer, Martin; Rosendaal, Frits R; Jukema, Johan W; Blom, Jeanet W; Numans, Mattijs E
2016-07-01
In contrast to structured, integrated risk assessment in primary care, unstructured risk factor screening outside primary care and corresponding recommendations to consult a general practitioner (GP) are often based on one abnormal value of a single risk factor. This study investigates the advantages and disadvantages of unstructured screening of blood pressure and cholesterol outside primary care. After the baseline visit of the Netherlands Epidemiology of Obesity study (population-based prospective cohort study in persons aged 45-65 years, recruited 2008-2012) all participants received a letter with results of blood pressure and cholesterol, and a recommendation to consult a GP if results were abnormal. Four years after the start of the study, participants received a questionnaire about the follow-up of their results. The study population consisted of 6343 participants, 48% men, mean age 56 years, mean body mass index 30 kg/m(2). Of all participants 66% had an abnormal result and, of these, 49% had a treatment indication based on the risk estimation system SCORE-NL 2006. Of the 25% of the participants who did not consult a GP, 40% had a treatment indication. Of the participants with an abnormal result 19% were worried, of whom 60% had no treatment indication. In this population 51% of the participants with an abnormal result had unnecessarily received a recommendation to consult a GP, and 10% were unnecessarily worried. GPs should be informed about the complete risk assessment, and only participants at intermediate or high risk should receive a recommendation to consult a GP. © The European Society of Cardiology 2015.
Wear compensating seal means for rotary piston coal feeder
Gencsoy, Hasan T.; Gardner, John F.
1979-01-01
The present invention is directed to a wear compensating seal arrangement for use in a rotary piston feeder utilized for feeding pulverized coal into a gasifier operating at relatively high pressures and elevated temperatures. The rotary piston feeder has a circular casing with a coal loading opening therein diametrically opposed from a coal discharge and contains a rotatable disoidal rotor having a cylinder in which a reciprocatable piston is disposed. The reciprocation of the piston within the cylinder is provided by a stationary conjugate cam whereby pulverized coal from a coal hopper at atmospheric pressure can be introduced into the cylinder and then discharged therefrom into the high pressure gasifier while maintaining minimal losses of producer gas and the expenditure of minimal energy which would detract from the efficiency of the gasification. The seal arrangement of the present invention is disposed between the rotor and the casing about the coal discharge and prevents the high pressure gases from within the gasifier from escaping between these relatively movable parts during operation of the coal feeder. The seal utilizes a primary seal in contact with the rotor and a secondary seal supporting the primary seal. The primary seal is continuously urged towards the rotor by springs and the high pressure producer gas.
Mauri, Laura; Kario, Kazuomi; Basile, Jan; Daemen, Joost; Davies, Justin; Kirtane, Ajay J; Mahfoud, Felix; Schmieder, Roland E; Weber, Michael; Nanto, Shinsuke; Azizi, Michel
2018-01-01
Catheter-based renal denervation is a new approach to treat hypertension via modulation of the renal sympathetic nerves. Although nonrandomized and small, open-label randomized studies resulted in significant reductions in office blood pressure 6months after renal denervation with monopolar radiofrequency catheters, the first prospective, randomized, sham-controlled study (Symplicity HTN-3) failed to meet its blood pressure efficacy end point. New clinical trials with new catheters have since been designed to address the limitations of earlier studies. Accordingly, the RADIANCE-HTN and REQUIRE studies are multicenter, blinded, randomized, sham-controlled trials designed to assess the blood pressure-lowering efficacy of the ultrasound-based renal denervation system (Paradise) in patients with established hypertension either on or off antihypertensive medications, is designed to evaluate patients in 2 cohorts-SOLO and TRIO, in the United States and Europe. The SOLO cohort includes patients with essential hypertension, at low cardiovascular risk, and either controlled on 1 to 2 antihypertensive medications or uncontrolled on 0 to 2 antihypertensive medications. Patients undergo a 4-week medication washout period before randomization to renal denervation (treatment) or renal angiogram (sham). The TRIO cohort includes patients with hypertension resistant to at least 3 antihypertensive drugs including a diuretic. Patients will be stabilized on a single-pill, triple-antihypertensive-drug combination for 4weeks before randomization to treatment or sham. Reduction in daytime ambulatory systolic blood pressure (primary end point) will be assessed at 2months in both cohorts. A predefined medication escalation protocol, as needed for blood pressure control, is implemented between 2 and 6months in both cohorts by a study staff member blinded to the randomization process. At 6months, daytime ambulatory blood pressure and antihypertensive treatment score will be assessed. REQUIRE is designed to evaluate patients with resistant hypertension on standard of care medication in Japan and Korea. Reduction in 24-hour ambulatory systolic blood pressure will be assessed at 3months (primary end point). Both studies are enrolling patients, and their results are expected in 2018. Copyright © 2017 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Bello, Nakone; Umar, Aishetu
2018-06-01
In the framework of the relativistic R3BP, we examine the effects of oblateness of the primary body and radiation pressure of the secondary on the positions and stability of the triangular points L4,5. It is found that the parameters involved all affect the positions and increase in any of the parameters leads to a reduction in the size of the region of stability. Thus establishing their destabilizing tendencies. The presence of positive real roots or positive real part in complex roots affirms the instability of L4,5 of the problem when applied to Cen X-4.
49 CFR 178.338-14 - Gauging devices.
Code of Federal Regulations, 2011 CFR
2011-10-01
... gauging devices, which accurately indicate the maximum permitted liquid level at the loading pressure, in... trycock line, or a differential pressure liquid level gauge must be used as the primary control for... filling. (2) The design pressure of each liquid level gauging device must be at least that of the tank. (3...
49 CFR 178.338-14 - Gauging devices.
Code of Federal Regulations, 2014 CFR
2014-10-01
... gauging devices, which accurately indicate the maximum permitted liquid level at the loading pressure, in... trycock line, or a differential pressure liquid level gauge must be used as the primary control for... filling. (2) The design pressure of each liquid level gauging device must be at least that of the tank. (3...
49 CFR 178.338-14 - Gauging devices.
Code of Federal Regulations, 2010 CFR
2010-10-01
..., a fixed trycock line, or a differential pressure liquid level gauge must be used as the primary... control for filling. (2) The design pressure of each liquid level gauging device must be at least that of... openings for dip tube gauging devices and pressure gauges in flammable cryogenic liquid service must be...
49 CFR 178.338-14 - Gauging devices.
Code of Federal Regulations, 2012 CFR
2012-10-01
... gauging devices, which accurately indicate the maximum permitted liquid level at the loading pressure, in... trycock line, or a differential pressure liquid level gauge must be used as the primary control for... filling. (2) The design pressure of each liquid level gauging device must be at least that of the tank. (3...
49 CFR 178.338-14 - Gauging devices.
Code of Federal Regulations, 2013 CFR
2013-10-01
... gauging devices, which accurately indicate the maximum permitted liquid level at the loading pressure, in... trycock line, or a differential pressure liquid level gauge must be used as the primary control for... filling. (2) The design pressure of each liquid level gauging device must be at least that of the tank. (3...
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.
The difference in blood pressure readings between arms and survival: primary care cohort study
Taylor, Rod S; Shore, Angela C; Campbell, John L
2012-01-01
Objective To determine whether a difference in systolic blood pressure readings between arms can predict a reduced event free survival after 10 years. Design Cohort study. Setting Rural general practice in Devon, United Kingdom. Participants 230 people receiving treatment for hypertension in primary care. Intervention Bilateral blood pressure measurements recorded at three successive surgery attendances. Main outcome measures Cardiovascular events and deaths from all causes during a median follow-up of 9.8 years. Results At recruitment 24% (55/230) of participants had a mean interarm difference in systolic blood pressure of 10 mm Hg or more and 9% (21/230) of 15 mm Hg or more; these differences were associated with an increased risk of all cause mortality (adjusted hazard ratio 3.6, 95% confidence interval 2.0 to 6.5 and 3.1, 1.6 to 6.0, respectively). The risk of death was also increased in 183 participants without pre-existing cardiovascular disease with an interarm difference in systolic blood pressure of 10 mm Hg or more or 15 mm Hg or more (2.6, 1.4 to 4.8 and 2.7, 1.3 to 5.4). An interarm difference in diastolic blood pressure of 10 mm Hg or more was weakly associated with an increased risk of cardiovascular events or death. Conclusions Differences in systolic blood pressure between arms can predict an increased risk of cardiovascular events and all cause mortality over 10 years in people with hypertension. This difference could be a valuable indicator of increased cardiovascular risk. Bilateral blood pressure measurements should become a routine part of cardiovascular assessment in primary care. PMID:22433975
Vu, Maihan B.; Halladay, Jacqueline R.; Miller, Cassandra; Garcia, Beverly A.; Cummings, Doyle M.; Cene, Crystal W.; Hinderliter, Alan; Little, Edwin; Rachide, Marjorie; DeWalt, Darren
2014-01-01
Introduction Patient and practice perspectives can inform development of team-based approaches to improving blood pressure control in primary care. We used a community-based participatory research approach to assess patient and practice perceptions regarding the value of team-based strategies for controlling blood pressure in a rural North Carolina population from 2010 through 2012. Methods In-depth interviews were conducted with 41 adults with hypertension, purposely sampled to include diversity of sex, race, literacy, and blood pressure control, and with key office staff at 5 rural primary care practices in the southeastern US “stroke belt.” Interviews explored barriers to controlling blood pressure, the practice’s role in controlling blood pressure, and opinions on the use of team care delivery. Results Patients reported that provider strategies to optimize blood pressure control should include regular visits, medication adjustment, side-effect discussion, and behavioral counseling. When discussing team-based approaches to hypertension care, patients valued verbal encouragement, calls from the doctor’s office, and the opportunity to ask questions. However, they voiced concerns about the effect of having too many people involved in their care. Practice staff focused on multiple, broad methods to control blood pressure including counseling, regular office visits, media to improve awareness, and support groups. An explicit focus of delivering care as teams was a newer concept. Conclusion When developing a team approach to hypertension treatment, patients value high-quality communication and not losing their primary relationship with their provider. Practice staff members were open to a team-based approach but had limited knowledge of what such an approach would entail. PMID:24762533
NASA Technical Reports Server (NTRS)
Khare, J. M.; Kentfield, J. A. C.
1979-01-01
A flexible, and easily modified, test rig is described which allows a one dimensional nonsteady flow stream to be generated, economically from a steady flow source of compressed air. This nonsteady flow is used as the primary stream in a nonsteady flow ejector constituting part of the test equipment. Standard piezo-electric pressure transducers etc. allow local pressures to be studied, as functions of time, in both the primary and secondary (mixed) flow portions of the apparatus. Provision is also made for measuring the primary and secondary mass flows and the thrust generated. Sample results obtained with the equipment are presented.
NASA Technical Reports Server (NTRS)
Atwell, Matthew J.; Hurlbert, Eric A.; Melcher, J. C.; Morehead, Robert L.
2017-01-01
An integrated cryogenic liquid oxygen, liquid methane (LOX/LCH4) reaction control system (RCS) was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. The RCS is a subsystem of the Integrated Cryogenic Propulsion Test Article (ICPTA), a pressure-fed LOX/LCH4 propulsion system composed of a single 2,800 lbf main engine, two 28 lbf RCS engines, and two 7 lbf RCS engines. Propellants are stored in four 48 inch diameter 5083 aluminum tanks that feed both the main engine and RCS engines in parallel. Helium stored cryogenically in a composite overwrapped pressure vessel (COPV) flows through a heat exchanger on the main engine before being used to pressurize the propellant tanks to a design operating pressure of 325 psi. The ICPTA is capable of simultaneous main engine and RCS operation. The RCS engines utilize a coil-on-plug (COP) ignition system designed for operation in a vacuum environment, eliminating corona discharge issues associated with a high voltage lead. There are two RCS pods on the ICPTA, with two engines on each pod. One of these two engines is a heritage flight engine from Project Morpheus. Its sea level nozzle was removed and replaced by an 85:1 nozzle machined using Inconel 718, resulting in a maximum thrust of 28 lbf under altitude conditions. The other engine is a scaled down version of the 28 lbf engine, designed to match the core and overall mixture ratios as well as other injector characteristics. This engine can produce a maximum thrust of 7 lbf with an 85:1 nozzle that was additively manufactured using Inconel 718. Both engines are film-cooled and capable of limited duration gas-gas and gas-liquid operation, as well as steady-state liquid-liquid operation. Each pod contains one of each version, such that two engines of the same thrust level can be fired as a couple on opposite pods. The RCS feed system is composed of symmetrical 3/8 inch lines that tap off of the main propellant manifold to send LOX and LCH4 outboard to the RCS pods. A Thermodynamic Vent System (TVS) is used to condition propellants at each pod by venting through an orifice and then routing the cold expansion products back through tubing that is welded along a large portion of the main RCS feed lines. Prior to final installation on the ICPTA, the RCS engines were tested in a small vacuum chamber at the Johnson Space Center (JSC) Energy Systems Test Area (ESTA) to verify functionality of the new COP ignition system and check out operation of the vacuum nozzles. After engine-level testing, the RCS engines were installed on the vehicle and a series of integrated hot-fire tests were performed at JSC consisting of various pulsing and steady-state firings as well as integrated main engine/RCS operation. The ICPTA was then integrated into the Plum Brook B-2 facility for vacuum and thermal/vacuum testing. Testing in the B-2 facility was composed of multiple thermal and pressure environments. The first set of tests were performed under ambient temperature and altitude pressure conditions. These tests consisted of a range of minimum impulse bit (MIB) pulsing sequences with low duty cycle, analogous to a coast phase in which the RCS is primarily used for station keeping. The primary goal of this sequence is to understand how propellant conditions were effected without an active TVS. In this scenario, consistent gas-gas operation is desirable since it results in a smaller MIB and more efficient propellant consumption. Multiple skin thermocouples are mounted on the feedlines, in addition to a submerged thermocouple on each commodity, in order to gather thermal data on the system. Higher duty cycle pulsing tests were then performed, analogous to an ascent or landing mission phase. The primary goal of this sequence was to examine how well the engines self-conditioned without active TVS when starting from a quiescent state. The TVS was then activated during some tests to demonstrate the capability to quickly condition the engines for higher pulsing demand scenarios. A thermocouple at the TVS outlet allows for the calculation of energy absorbed by the vented propellant. Lastly, tests with longer pulses and multiple engines firing either in sequence or simultaneously were run in order to gather transient system response data on waterhammer. Six total high-speed pressure transducers are installed on the RCS system, one sensor at the end of each propellant manifold line on the pods, and one at the tap-off location for each commodity. This will allow for the accurate characterization of waterhammer in the system under various propellant conditions and firing sequences. Other instrumentation for this test series includes nozzle throat thermocouples, chamber pressure measurement, heat soakback measurement, and tank wall plume impingement temperature measurement. The next set of tests were performed to demonstrate simultaneous main engine and RCS operation. Data from this test will be used to examine if there is any change to nominal operation of the RCS as a result of feed system interaction or other phenomenon. Some of these tests began under high vacuum conditions (target ambient pressure less than 1x10(exp -3) torr) and others began at altitude conditions. The last set of tests were performed with the B-2 cold wall active. Under these tests, many of the same low duty cycle MIB tests were repeated in order to characterize how propellant conditions changed with the lower heat leak. In this scenario the RCS manifold experiences much less heat leak, resulting in a change to how well the engines self-condition. As a result, an increase in maximum waterhammer pressures and a change in natural frequency of the system was expected due to higher density propellants. The lower heat leak should also result in a change to the MIB pulse profile, and data will be examined to understand how MIB repeatability is affected in the different operating environments. Parallel to the test efforts, a set of transient model development efforts were made to predict RCS performance. The primary effort was aimed at producing a SINDA/FLUINT model to predict propellant conditioning up to the engine inlet as a function of different environmental and operating parameters, with the goal of predicting chamber pressure, TVS performance, and propellant consumption over time. Preliminary results for this effort will be presented in comparison with test data. Additional modeling efforts were made using SINDA/FLUINT to predict waterhammer in the system since the software is capable of handling multiphase transient fluid dynamics. These results will be compared with the high-speed pressure transducer test data for validation purposes.
Balijepalli, Chakrapani; Bramlage, Peter; Lösch, Christian; Zemmrich, Claudia; Humphries, Karin H; Moebus, Susanne
2014-06-01
Contemporary epidemiological data on blood pressure readings, hypertension prevalence and control in unselected patient populations covering a broad age range are scarce. The aim here is to report the prevalence of high blood pressure and to identify factors associated with blood pressure control in a large German primary care sample. We used data from the German Metabolic and Cardiovascular Risk Study including 35 869 patients aged 18-99 years. High blood pressure was defined as systolic blood pressure ≥140 mm Hg and/or diastolic blood pressure ≥90 mm Hg or using antihypertensive therapy. Factors associated with blood pressure control among patients receiving antihypertensive therapy were examined using multiple logistic regressions to estimate odds ratios and 95% confidence intervals. The prevalence of high blood pressure, uncontrolled high blood pressure and untreated high blood pressure was 54.8%, 21.3% and 17.6%, respectively. Age >50 years (1.52; 1.40-1.65), male sex (1.30; 1.20-1.41), elevated waist circumference (1.55; 1.45-1.65), high cholesterol (1.24; 1.16-1.33), high triglycerides (1.11; 1.04-1.19) and concomitant diabetes (1.29; 1.20-1.40) were independently associated with uncontrolled high blood pressure. In a majority of patients we observed hypertension despite treatment for high blood pressures. Studies examining the reasons for treatment failure are highly warranted.
NASA Technical Reports Server (NTRS)
Goldberg, Ben E.; Wiley, Dan R.
1991-01-01
An overview is presented of hybrid rocket propulsion systems whereby combining solids and liquids for launch vehicles could produce a safe, reliable, and low-cost product. The primary subsystems of a hybrid system consist of the oxidizer tank and feed system, an injector system, a solid fuel grain enclosed in a pressure vessel case, a mixing chamber, and a nozzle. The hybrid rocket has an inert grain, which reduces costs of development, transportation, manufacturing, and launch by avoiding many safety measures that must be taken when operating with solids. Other than their use in launch vehicles, hybrids are excellent for simulating the exhaust of solid rocket motors for material development.
Plug nozzles: The ultimate customer driven propulsion system
NASA Technical Reports Server (NTRS)
Aukerman, Carl A.
1991-01-01
This paper presents the results of a study applying the plug cluster nozzle concept to the propulsion system for a typical lunar excursion vehicle. Primary attention for the design criteria is given to user defined factors such as reliability, low volume, and ease of propulsion system development. Total thrust and specific impulse are held constant in the study while other parameters are explored to minimize the design chamber pressure. A brief history of the plug nozzle concept is included to point out the advanced level of technology of the concept and the feasibility of exploiting the variables considered in this study. The plug cluster concept looks very promising as a candidate for consideration for the ultimate customer driven propulsion system.
NASA Technical Reports Server (NTRS)
Aukerman, Carl A.
1991-01-01
This paper presents the results of a study applying the plug cluster nozzle concept to the propulsion system for a typical lunar excursion vehicle. Primary attention for the design criteria is given to user defined factors such as reliability, low volume, and ease of propulsion system development. Total thrust and specific impulse are held constant in the study while other parameters are explored to minimize the design chamber pressure. A brief history of the plug nozzle concept is included to point out the advanced level of technology of the concept and the feasibility of exploiting the variables considered in the study. The plug cluster concept looks very promising as a candidate for consideration for the ultimate customer driven propulsion system.
NASA Technical Reports Server (NTRS)
Stevens, N. J.; Berkopec, F. D.; Blech, R. A.
1976-01-01
The NASA/USAF program on the Environmental Charging of Spacecraft Surfaces consists, in part, of experimental efforts directed toward evaluating the response of materials to the environmental charged particle flux. Samples of thermal blankets of the type to be used on the Global Positioning System Flight Space Vehicles were tested to determine their response to electron flux. The primary result observed was that no discharges were obtained with the quartz-fiber-fabric-covered multilayer insulation specimen. The taped aluminized polyester grounding system used on all specimens did not appear to grossly deteriorate with time; however, the specimens require specific external pressure to maintain constant grounding system resistance.
Corlin, Laura; Woodin, Mark; Hart, Jaime E; Simon, Matthew C; Gute, David M; Stowell, Joanna; Tucker, Katherine L; Durant, John L; Brugge, Doug
2018-04-05
Few longitudinal studies have examined the association between ultrafine particulate matter (UFP, particles < 0.1 μm aerodynamic diameter) exposure and cardiovascular disease (CVD) risk factors. We used data from 791 adults participating in the longitudinal Boston Puerto Rican Health Study (Massachusetts, USA) between 2004 and 2015 to assess whether UFP exposure was associated with blood pressure and high sensitivity C-reactive protein (hsCRP, a biomarker of systemic inflammation). Residential annual average UFP exposure (measured as particle number concentration, PNC) was assigned using a model accounting for spatial and temporal trends. We also adjusted PNC values for participants' inhalation rate to obtain the particle inhalation rate (PIR) as a secondary exposure measure. Multilevel linear models with a random intercept for each participant were used to examine the association of UFP with blood pressure and hsCRP. Overall, in adjusted models, an inter-quartile range increase in PNC was associated with increased hsCRP (β = 6.8; 95% CI = - 0.3, 14.0%) but not with increased systolic blood pressure (β = 0.96; 95% CI = - 0.33, 2.25 mmHg), pulse pressure (β = 0.70; 95% CI = - 0.27, 1.67 mmHg), or diastolic blood pressure (β = 0.55; 95% CI = - 0.20, 1.30 mmHg). There were generally stronger positive associations among women and never smokers. Among men, there were inverse associations of PNC with systolic blood pressure and pulse pressure. In contrast to the primary findings, an inter-quartile range increase in the PIR was positively associated with systolic blood pressure (β = 1.03; 95% CI = 0.00, 2.06 mmHg) and diastolic blood pressure (β = 1.01; 95% CI = 0.36, 1.66 mmHg), but not with pulse pressure or hsCRP. We observed that exposure to PNC was associated with increases in measures of CVD risk markers, especially among certain sub-populations. The exploratory PIR exposure metric should be further developed.
Impact of systemically active neurohumoral factors on the erectile response of the rat.
MacKenzie, Lindsay D; Heaton, Jeremy P W; Adams, Michael A
2011-09-01
Mean arterial pressure (MAP) and specific regulation of penile blood flow are the primary determinants of an erection. While this concept is well recognized, the differential relationship between systemically acting vasoactive factors on arterial pressure and erectile responses is not well described. The aim of this study was to determine how the modification of systemic levels of neurohumoral factors impacts on the magnitude and efficiency of the erectile response. The main outcome measures for this study are changes in MAP and intracavernosal pressure (ICP) following electrostimulation of the cavernous nerve. Anesthetized adult, male Sprague-Dawley rats were catheterized for measuring MAP (carotid), ICP, and drug administration (vena cava). Erections were induced via cavernous nerve electrostimulation. Vasoactive drug infusions were used to produce changes in MAP levels including: hexamethonium, angiotensin II (ANGII)±hexamethonium, methoxamine±hexamethonium, losartan, MAHMA NONOate, and terbutaline. In general, ICP and MAP were linearly correlated regardless of treatment. Hexamethonium markedly dropped MAP and proportionately decreased the magnitude of the erectile response. ANGII or methoxamine given to hexamethonium-pretreated or untreated rats increased MAP similarly, but produced contrasting effects on erectile responses. ANGII-induced pressor responses were associated with increased erectile responses whereas all methoxamine treatments markedly decreased erectile responses. Depressor changes with losartan or terbutaline, but not MAHMA NONOate, also impacted negatively on the efficiency of the erectile responses at lower arterial pressures. In general, the magnitude of the erectile responses was found to be dependent upon the level of MAP, although the mechanism by which arterial pressure was changed impacted substantially on the characteristics of the relationship. The major finding was that circulation-wide α-adrenoceptor stimulation was extremely deleterious to erectile responses whereas global stimulation of ANG II receptors was actually proerectile. Overall, the results indicate that neurohumoral specificity in systemic hemodynamic control is also critical in establishing the optimal erectile environment in rats. © 2011 International Society for Sexual Medicine.
[CHARACTERISTIC FEATURES OF PRESSURE ULCER INFECTION].
Kučišec-Tepeš, N
2016-01-01
Pressure ulcer is a localized injury of the skin and/or adjacent tissue, usually above bone protrusions. It is a result of pressure or pressure combined with shear stress, friction and humidity. With regard to long life and delayed healing, it is a chronic wound. Pressure ulcer appears as a consequence of a combination of micro-embolism, ischemia and myonecrosis. These pathophysiological processes provide an ideal medium for proliferation of microorganisms, predominantly bacteria, and development of infection. Progression in the development of pressure ulcer is a dynamic process manifesting in phases, each of which is characterized by its own physiological-anatomical peculiarities and microbiological status. An open lesion without protective barrier becomes contaminated immediately, and, shortly afterwards, colonized by physiological microflora of the host and microbes from the environment. In the absence of preventive measures, the wound becomes critically colonized and infected. The characteristic of chronic wound/pressure ulcer is that it is colonized, and the infection develops depending on various factors in 5% to 80% of cases. The ability of microbes to cause infection depends on a number of factors, which include the pathogen and the host. The number and quantity of virulent factors, microbes, determines the virulence coefficient, which is responsible for overcoming the host’s immune system and development of infection. In the development of pressure ulcer infection, two essential microbial factors predominate, i.e. the presence of adhesin and association with biofilm. Thus, pressure ulcer infection as a chronic wound is characterized by a polymicrobial and heterogeneous population of microbes, domination of biofilm phenotype as a primary factor of virulence present in 90% of cases, phenotype hypervariability of species, and resistance or tolerance of the etiological agents to all types of biocides. The most significant virulence factor is biofilm. It is a corporative community of microbes with a clear architecture managed by quorum sensing molecules. It is through them that the communication between species takes place, the phenotype and virulence change, and resistance develops at the level of genome. The formation of biofilm takes place in several stages, and the speed is measured in hours. Microorganisms in the biofilm are protected from the action of the host’s immune system and, likewise, they are tolerant or resistant to antibiotics, antiseptics, and stress. Bacteria causing pressure ulcer infection are characterized as opportunistic, but also primarily pathogenic. The dominance and combination of species depend on the duration, localization and stage of pressure ulcer. The predominant etiological agents are Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa and Peptostreptococcus spp. Nowadays, multiple-resistant strains predominate, such as MRSA, Acinetobacter spp. and Pseudomonas spp. A chronic wound such as pressure ulcer is ideal for the development of infection, especially if targeted preventive measures are not applied. The diagnosis of infection is complex and is based on the combination of primary and secondary clinical symptoms, tissue in the wound, status of the wound environment, inflammation markers, and results of microbiological examination of targeted samples – biopsies, which are the gold standard. In reaching the diagnosis of infection, it is crucial to differentiate critical colonization from deep tissue infection, which is based on clinical criteria called NERDS-STONEES. The frequency of pressure ulcer infection is 5% to 80%, and biofilm is present in 90% of cases. Due knowledge of the epidemiology of pressure ulcer and follow up of complications such as infection make the basis for the understanding of chronic wound, efforts to improve necessary care, prevention of development and application of a combination of treatment strategies.
Hydro-ball in-core instrumentation system and method of operation
Tower, Stephen N.; Veronesi, Luciano; Braun, Howard E.
1990-01-01
A hydro-ball in-core instrumentation system employs detector strings each comprising a wire having radiation sensitive balls affixed diametrically at spaced positions therealong and opposite tip ends of which are transportable by fluid drag through interior passageways. In the passageways primary coolant is caused to flow selectively in first and second opposite directions for transporting the detector strings from stored positions in an exterior chamber to inserted positions within the instrumentation thimbles of the fuel rod assemblies of a pressure vessel, and for return. The coolant pressure within the detector passageways is the same as that within the vessel; face contact, disconnectable joints between sections of the interior passageways within the vessel facilitate assembly and disassembly of the vessel for refueling and routine maintenance operations. The detector strings may pass through a very short bend radius thereby minimizing space requirements for the connections of the instrumentation system to the vessel and concomitantly the vessel containment structure. Improved radiation mapping and a significant reduction in potential exposure of personnel to radiation are provided. Both top head and bottom head penetration embodiments are disclosed.
High pressure cosmochemistry applied to major planetary interiors: Experimental studies
NASA Technical Reports Server (NTRS)
Nicol, M. F.; Johnson, M.; Koumvakalis, A. S.
1984-01-01
Progress is reported on a project to determine the properties and boundaries of high pressure phases of the H2-He-H2O-NH3-CH4 system that are needed to constrain theoretical models of the interiors of the major planets. This project is one of the first attempts to measure phase equilibria in binary fluid-solid systems in diamond anvil cells. Vibrational spectroscopy, direct visual observations, and X-ray diffraction crystallography of materials confined in externally heated cells are the primary experimental probes. Adiabats of these materials are also measured in order to constrain models of heat flow in these bodies and to detect phase transitions by thermal anomalies. Initial efforts involve the NH3-H2O binary. This system is especially relevant to models for surface reconstruction of the icy satellites of Jupiter and Saturn. Thermal analysis experiments were completed for the P-X space, p4GPa:0 or = 0.50, near room temperature. The cryostat, sample handling equipment, and optics needed to extend the optical P-T-X work below room temperature was completed.
Preliminary Design of Critical Function Monitoring System of PGSFR
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
2015-07-01
A PGSFR (Prototype Gen-IV Sodium-cooled Fast Reactor) is under development at Korea Atomic Energy Research Institute. A critical function monitoring system of the PGSFR is preliminarily studied. The functions of CFMS are to display critical plant variables related to the safety of the plant during normal and accident conditions and guide the operators corrective actions to keep the plant in a safe condition and mitigate the consequences of accidents. The minimal critical functions of the PGSFR are composed of reactivity control, reactor core cooling, reactor coolant system integrity, primary heat transfer system(PHTS) heat removal, sodium water reaction mitigation, radiation controlmore » and containment conditions. The variables and alarm legs of each critical function of the PGSFR are as follows; - Reactivity control: The variables of reactivity control function are power range neutron flux instrumentation, intermediate range neutron flux instrumentation, source range neutron flux instrumentation, and control rod bottom contacts. The alarm leg to display the reactivity controls consists of status of control drop malfunction, high post trip power and thermal reactivity addition. - Reactor core cooling: The variables are PHTS sodium level, hot pool temperature of PHTS, subassembly exit temperature, cold pool temperature of the PHTS, PHTS pump current, and PHTS pump breaker status. The alarm leg consists of high core delta temperature, low sodium level of the PHTS, high subassembly exit temperature, and low PHTS pump load. - Reactor coolant system integrity: The variables are PHTS sodium level, cover gas pressure, and safeguard vessel sodium level. The alarm leg is composed of low sodium level of PHTS, high cover gas pressure and high sodium level of the safety guard vessel. - PHTS heat removal: The variables are PHTS sodium level, hot pool temperature of PHTS, core exit temperature, cold pool temperature of the PHTS, flow rate of passive residual heat removal system, flow rate of active residual heat removal system, and temperatures of air heat exchanger temperature of residual heat removal systems. The alarm legs are composed of two legs of a 'passive residual heat removal system not cooling' and 'active residual heat removal system not cooling'. - Sodium water reaction mitigation: The variables are intermediate heat transfer system(IHTS) pressure, pressure and temperature and level of sodium dump tank, the status of rupture disk, hydrogen concentration in IHTS and direct variable of sodium-water-reaction measure. The alarm leg consists of high IHTS pressure, the status of sodium water reaction mitigation system and the indication of direct measure. - Radiation control: The variables are radiation of PHTS, radiation of IHTS, and radiation of containment purge. The alarm leg is composed of high radiation of PHTS and IHTS, and containment purge system. - Containment condition: The variables are containment pressure, containment isolation status, and sodium fire. The alarm leg consists of high containment pressure, status of containment isolation and status of sodium fire. (authors)« less
Lin, Tung-Liang; Sheen, Huey-Min; Chung, Chin-Teng; Yang, Sai-Wei; Lin, Shih-Yi; Luo, Hong-Ji; Chen, Chung-Yu; Chan, I-Cheng; Shih, Hsu-Sheng; Sheu, Wayne Huey-Herng
2013-07-29
Removable plug insoles appear to be beneficial for patients with diabetic neuropathic feet to offload local plantar pressure. However, quantitative evidence of pressure reduction by means of plug removal is limited. The value of additional insole accessories, such as arch additions, has not been tested. The purpose of this study was to evaluate the effect of removing plugs from foam based insoles, and subsequently adding extra arch support, on plantar pressures. In-shoe plantar pressure measurements were performed on 26 patients with diabetic neuropathic feet at a baseline condition, in order to identify the forefoot region with the highest mean peak pressure (MPP). This was defined as the region of interest (ROI) for plug removal.The primary outcome was measurement of MPP using the pedar® system in the baseline and another three insole conditions (pre-plug removal, post-plug removal, and post-plug removal plus arch support). Among the 26 ROIs, a significant reduction in MPP (32.3%, P<0.001) was found after removing the insole plugs. With an arch support added, the pressure was further reduced (9.5%, P<0.001). There were no significant differences in MPP at non-ROIs between pre- and post-plug removal conditions. These findings suggest that forefoot plantar pressure can be reduced by removing plugs and adding arch support to foam-based insoles. This style of insole may therefore be clinically useful in managing patients with diabetic peripheral neuropathy.
Posser, Simone Regina; Callegaro, Carine Cristina; Beltrami-Moreira, Marina; Moreira, Leila Beltrami
2016-08-02
Hypertension is a complex chronic condition characterized by elevated arterial blood pressure. Management of hypertension includes non-pharmacologic strategies, which may include techniques that effectively reduce autonomic sympathetic activity. Respiratory exercises improve autonomic control over cardiovascular system and attenuate muscle metaboreflex. Because of these effects, respiratory exercises may be useful to lower blood pressure in subjects with hypertension. This randomized, double-blind clinical trial will test the efficacy of inspiratory muscle training in reducing blood pressure in adults with essential hypertension. Subjects are randomly allocated to intervention or control groups. Intervention consists of inspiratory muscle training loaded with 40 % of maximum inspiratory pressure, readjusted weekly. Control sham intervention consists of unloaded exercises. Systolic and diastolic blood pressures are co-primary endpoint measures assessed with 24 h ambulatory blood pressure monitoring. Secondary outcome measures include cardiovascular autonomic control, inspiratory muscle metaboreflex, cardiopulmonary capacity, and inspiratory muscle strength and endurance. Previously published work suggests that inspiratory muscle training reduces blood pressure in persons with hypertension, but the effectiveness of this intervention is yet to be established. We propose an adequately sized randomized clinical trial to test this hypothesis rigorously. If an effect is found, this study will allow for the investigation of putative mechanisms to mediate this effect, including autonomic cardiovascular control and metaboreflex. ClinicalTrials.gov NCT02275377 . Registered on 30 September 2014.
... other complications. Increased pressure in the portal vein (portal hypertension). Blood from your intestine, spleen and pancreas enters ... specific complications: Increased pressure in the portal vein (portal hypertension). Your doctor is likely to screen and monitor ...
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 facility, 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. Although the real-time signal measurements support qualitative remarks on ejector performance, extracting quantitative ejector dynamic response was impeded by excessive aerodynamic noise and thrust stand dynamic (resonance) characteristics. It does appear, however, that a quasi-steady performance assumption is valid for this model with primary nozzle pressure increased on the order of 50 lb(sub f)/s. Transient signal treatment of the present dataset is discussed and initial interpretations of the results are compared with theoretical predictions for a similar Short Takeoff and Vertical Landing (STOVL) ejector model.
Air cleaning performance of a new environmentally controlled primary crusher operator booth
Organiscak, J.A.; Cecala, A.B.; Zimmer, J.A.; Holen, B.; Baregi, J.R.
2016-01-01
The National Institute for Occupational Safety and Health (NIOSH) cooperated with 3M Company in the design and testing of a new environmentally controlled primary crusher operator booth at the company’s Wausau granite quarry near Wausau, WI. This quarry had an older crusher booth without a central heating, ventilation and air conditioning (HVAC) system, and without an air filtration and pressurization system. A new replacement operator booth was designed and installed by 3M based on design considerations from past NIOSH research on enclosed cab filtration systems. NIOSH conducted pre-testing of the old booth and post-testing of the new booth to assess the new filtration and pressurization system’s effectiveness in controlling airborne dusts and particulates. The booth’s dust and particulate control effectiveness is described by its protection factor, expressed as a ratio of the outside to inside concentrations measured during testing. Results indicate that the old booth provided negligible airborne respirable dust protection and low particulate protection from the outside environment. The newly installed booth provided average respirable dust protection factors from 2 to 25 over five shifts of dust sampling with occasional worker ingress and egress from the booth, allowing some unfiltered contaminants to enter the enclosure. Shorter-term particle count testing outside and inside the booth under near-steady-state conditions, with no workers entering or exiting the booth, resulted in protection factors from 35 to 127 on 0.3- to 1.0-μm respirable size particulates under various HVAC airflow operating conditions. PMID:26937052
Blast-Induced Acceleration in a Shock Tube: Distinguishing Primary and Tertiary Blast Injury
2015-10-01
these well-defined exposure conditions, anesthetized rats are used to simultaneously record intracranial pressure (ICP), intravascular pressure , and...blast flow conditions (e.g. peak static and total pressure , positive phase duration, and impulse) and acceleration and displacement of a wide range of...resultant pressure responses in varied compartments in concert with the neuropathological, neurochemical, and neurobehavioral consequences of exposures
1991-04-01
Boiler and Pressure Vessel Code . Other design requirements are developed from standard safe... Boiler and Pressure Vessel Code . The following three condi- tions constitute the primary design parameters for pressure vessels: (a) Design Working...rules and practices of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code . Section VIII, Division 1 of the ASME
Blood Pressure and Arterial Load After Transcatheter Aortic Valve Replacement for Aortic Stenosis.
Lindman, Brian R; Otto, Catherine M; Douglas, Pamela S; Hahn, Rebecca T; Elmariah, Sammy; Weissman, Neil J; Stewart, William J; Ayele, Girma M; Zhang, Feifan; Zajarias, Alan; Maniar, Hersh S; Jilaihawi, Hasan; Blackstone, Eugene; Chinnakondepalli, Khaja M; Tuzcu, E Murat; Leon, Martin B; Pibarot, Philippe
2017-07-01
After aortic valve replacement, left ventricular afterload is often characterized by the residual valve obstruction. Our objective was to determine whether higher systemic arterial afterload-as reflected in blood pressure, pulsatile and resistive load-is associated with adverse clinical outcomes after transcatheter aortic valve replacement (TAVR). Total, pulsatile, and resistive arterial load were measured in 2141 patients with severe aortic stenosis treated with TAVR in the PARTNER I trial (Placement of Aortic Transcatheter Valve) who had systolic blood pressure (SBP) and an echocardiogram obtained 30 days after TAVR. The primary end point was 30-day to 1-year all-cause mortality. Lower SBP at 30 days after TAVR was associated with higher mortality (20.0% for SBP 100-129 mm Hg versus 12.0% for SBP 130-170 mm Hg; P <0.001). This association remained significant after adjustment, was consistent across subgroups, and confirmed in sensitivity analyses. In adjusted models that included SBP, higher total and pulsatile arterial load were associated with increased mortality ( P <0.001 for all), but resistive load was not. Patients with low 30-day SBP and high pulsatile load had a 3-fold higher mortality than those with high 30-day SBP and low pulsatile load (26.1% versus 8.1%; hazard ratio, 3.62; 95% confidence interval, 2.36-5.55). Even after relief of valve obstruction in patients with aortic stenosis, there is an independent association between post-TAVR blood pressure, systemic arterial load, and mortality. Blood pressure goals in patients with a history of aortic stenosis may need to be redefined. Increased pulsatile arterial load, rather than blood pressure, may be a target for adjunctive medical therapy to improve outcomes after TAVR. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00530894. © 2017 American Heart Association, Inc.
Yuan, Hongwei; Poeggel, Sven; Newe, Thomas; Lewis, Elfed; Viphavakit, Charusluk; Leen, Gabriel
2017-03-10
A comprehensive study of the effect of a wide range of controlled human subject motion on Photoplethysmographic signals is reported. The investigation includes testing of two separate groups of 5 and 18 subjects who were asked to undertake set exercises whilst simultaneously monitoring a wide range of physiological parameters including Breathing Rate, Heart Rate and Localised Blood Pressure using commercial clinical sensing systems. The unique finger mounted PPG probe equipped with miniature three axis accelerometers for undertaking this investigation was a purpose built in-house version which is designed to facilitate reproducible application to a wide range of human subjects and the study of motion. The subjects were required to undertake several motion based exercises including standing, sitting and lying down and transitions between these states. They were also required to undertake set arm movements including arm-swinging and wrist rotation. A comprehensive set of experimental results corresponding to all motion inducing exercises have been recorded and analysed including the baseline (BL) value (DC component) and the amplitude of the oscillation of the PPG. All physiological parameters were also recorded as a simultaneous time varying waveform. The effects of the motion and specifically the localised Blood Pressure (BP) have been studied and related to possible influences of the Autonomic Nervous System (ANS) and hemodynamic pressure variations. It is envisaged that a comprehensive study of the effect of motion and the localised pressure fluctuations will provide valuable information for the future minimisation of motion artefact effect on the PPG signals of this probe and allow the accurate assessment of total haemoglobin concentration which is the primary function of the probe.
... become inflamed (Buerger's disease), and a type of high blood pressure that affects the arteries of the lungs (primary ... medications. These include beta blockers, used to treat high blood pressure; migraine medications that contain ergotamine or sumatriptan; attention- ...
NASA Astrophysics Data System (ADS)
Fugger, Christopher A.
Staged combustion is one design approach in a gas turbine engine to reduce pollutant emission levels. In axially staged combustion, portions of the air and fuel are injected downstream of a lean premixed low NOx primary combustion zone. The gas residence time at elevated temperatures is decreased resulting in lower thermal NOx, and the reduced oxygen and high temperature vitiated primary zone flow further help to reduce pollutant emissions and quickly complete combustion. One implementation of axially staged combustion is transverse fuel jet injection. An important consideration for staged combustion systems, though, is how the primary and secondary combustion zones can couple through the acoustic resonances of the chamber. These couplings can lead to additional source terms that pump energy into the resonant acoustic field and help sustain the high-amplitude combustor pressure oscillations. An understanding of these couplings is important so that it may be possible to design a secondary combustion system that provides inherent damping to the combustor system. To systematically characterize the coupling of a reacting jet in unsteady crossflow in detail, the effects of an an unsteady pressure flowfield and an unsteady velocity flowfield are separately investigated. An optically accessible resonant combustion chamber was designed and built as part of this work to generate a standing wave unsteady vitiated crossflow at a chamber pressure of 0.9 MPa. The location of transverse jet injection corresponds to one of two locations, where one location is the pressure node and the other location the pressure anti-node of the resonant chamber acoustic mode. The injection location is optically accessible, and the dynamic interactions between the transverse jet flow and the 1st and 2nd axial combustor modes are measured using 10 kHz OH-PLIF and 2D PIV. This document analyzes five test cases: two non-reacting jets and three reacting jets. All cases correspond to jet injection near a pressure node of the 1st axial combustor mode, where the dominant flowfield fluctuations are a time-varying crossflow velocity. For the non-reacting jets, the nominal jet-to-crossflow momentum flux ratio is 19. For the reacting jets, the nominal jet-to-crossflow momentum flux ratio is 6. Two cross sectional planes parallel to the jet injection wall are investigated: 1 and 2.7 jet diameters from the jet injection wall. The combustor crossflow high frequency wall mounted pressure data is given for each test case. The velocity and OH-PLIF data is presented as instantaneous snapshots, time and phase averaged flowfields, modal decompositions using Proper Orthogonal Decomposition and Dynamic Mode Decomposition, and a jet cycle analysis relative to the crossflow acoustic cycle. Analysis of the five test cases shows that the jet cross sectional velocity and OH-PLIF dynamics display a multitude of dynamics. These are often organized into shear layer dynamics and wake dynamics, but are not mutually exclusive. For large unsteady crossflow velocity oscillations at the 1st axial combustor mode, both dynamics show strong organization at the unsteady crossflow frequency. Deciphering these dynamics is complicated by the fact that the ostensible jet response to the time-varying crossflow is a time-varying jet penetration. This drives the jet toward and away from the jet injection wall. These motions are perpendicular to the laser sheet and creates significant out-of-plane motions. The amplitude of crossflow unsteadiness appears to play a role in the sharpness of the wake dynamics. For the non-reacting cases, the wake dynamics are strong and dominant spectral features in the flowfield. For the reacting cases, the wake dynamics are spectrally distinct in the lower amplitude crossflow unsteadiness case, but a large unsteady amplitude crossflow appears to suppress the spectral bands in the frequency range corresponding to wake vortex dynamics.
The effects of low tidal ventilation on lung strain correlate with respiratory system compliance.
Xie, Jianfeng; Jin, Fang; Pan, Chun; Liu, Songqiao; Liu, Ling; Xu, Jingyuan; Yang, Yi; Qiu, Haibo
2017-02-03
The effect of alterations in tidal volume on mortality of acute respiratory distress syndrome (ARDS) is determined by respiratory system compliance. We aimed to investigate the effects of different tidal volumes on lung strain in ARDS patients who had various levels of respiratory system compliance. Nineteen patients were divided into high (C high group) and low (C low group) respiratory system compliance groups based on their respiratory system compliance values. We defined compliance ≥0.6 ml/(cmH 2 O/kg) as C high and compliance <0.6 ml/(cmH 2 O/kg) as C low . End-expiratory lung volumes (EELV) at various tidal volumes were measured by nitrogen wash-in/washout. Lung strain was calculated as the ratio between tidal volume and EELV. The primary outcome was that lung strain is a function of tidal volume in patients with various levels of respiratory system compliance. The mean baseline EELV, strain and respiratory system compliance values were 1873 ml, 0.31 and 0.65 ml/(cmH 2 O/kg), respectively; differences in all of these parameters were statistically significant between the two groups. For all participants, a positive correlation was found between the respiratory system compliance and EELV (R = 0.488, p = 0.034). Driving pressure and strain increased together as the tidal volume increased from 6 ml/kg predicted body weight (PBW) to 12 ml/kg PBW. Compared to the C high ARDS patients, the driving pressure was significantly higher in the C low patients at each tidal volume. Similar effects of lung strain were found for tidal volumes of 6 and 8 ml/kg PBW. The "lung injury" limits for driving pressure and lung strain were much easier to exceed with increases in the tidal volume in C low patients. Respiratory system compliance affected the relationships between tidal volume and driving pressure and lung strain in ARDS patients. These results showed that increasing tidal volume induced lung injury more easily in patients with low respiratory system compliance. Clinicaltrials.gov identifier NCT01864668 , Registered 21 May 2013.
Development of a Dew-Point Generator for Gases Other than Air and Nitrogen and Pressures up to 6 MPa
NASA Astrophysics Data System (ADS)
Bosma, R.; Peruzzi, A.
2012-09-01
A new primary humidity standard is currently being developed at VSL that, in addition to ordinary operation with air and nitrogen at atmospheric pressure, can be operated also with special carrier gases such as natural gas and SF6 and at pressures up to 6 MPa. In this paper, the design and construction of this new primary dew-point generator and the preliminary tests performed on the generator are reported. The results of the first efficiency tests, performed for the dew-point temperature range from -50 °C to 20°C, for pressures up to 0.7MPa and for carrier gas flow rates up to 4L· min-1, showed satisfactory generator performance when used in the single-pass mode, i.e., with no recirculation of the carrier gas.
A High Pressure Flowing Oil Switch For Gigawatt, Repetitive Applications
2005-06-01
for testing the high pressure switch concept under repetitive pulse conditions is a 4.8 Ω, 70 ns water pulse forming line (PFL). The water PFL is...Cox Instruments. A pair of Hedland variable area flow sensors monitored relative flow rates in the two oil lines that fed the high pressure switch . High... pressure switch was tested under both single shot and repetitive conditions over a range of pressures, flow rates and temperatures. The primary
Yamakoshi, Yoshiki
2016-01-01
Blood circulation function of peripheral blood vessels in skin dermis was evaluated employing an optical sensor with a pressurization mechanism using the blood outflow and reflow characteristics. The device contains a light source and an optical sensor. When applied to the skin surface, it first exerts the primary pressure (higher than the systolic blood pressure), causing an outflow of blood from the dermal peripheral blood vessels. After two heartbeats, the pressure is lowered (secondary pressure) and blood reflows into the peripheral blood vessels. Hemoglobin concentration, which changes during blood outflow and reflow, is derived from the received light intensity using the Beer–Lambert law. This method was evaluated in 26 healthy female volunteers and 26 female scleroderma patients. In order to evaluate the blood circulation function of the peripheral blood vessels of scleroderma patients, pressurization sequence which consists of primary pressure followed by secondary pressure was adopted. Blood reflow during the first heartbeat period after applying the secondary pressure of 40mmHg was (mean±SD) 0.059±0.05%mm for scleroderma patients and 0.173±0.104%mm for healthy volunteers. Blood reflow was significantly lower in scleroderma patients than in healthy volunteers (p<0.05). This result indicates that the information necessary for assessing blood circulation disorder of peripheral blood vessels in scleroderma patients is objectively obtained by the proposed method. PMID:27479094
Yamakoshi, Yoshiki; Motegi, Sei-Ichiro; Ishikawa, Osamu
2016-01-01
Blood circulation function of peripheral blood vessels in skin dermis was evaluated employing an optical sensor with a pressurization mechanism using the blood outflow and reflow characteristics. The device contains a light source and an optical sensor. When applied to the skin surface, it first exerts the primary pressure (higher than the systolic blood pressure), causing an outflow of blood from the dermal peripheral blood vessels. After two heartbeats, the pressure is lowered (secondary pressure) and blood reflows into the peripheral blood vessels. Hemoglobin concentration, which changes during blood outflow and reflow, is derived from the received light intensity using the Beer-Lambert law. This method was evaluated in 26 healthy female volunteers and 26 female scleroderma patients. In order to evaluate the blood circulation function of the peripheral blood vessels of scleroderma patients, pressurization sequence which consists of primary pressure followed by secondary pressure was adopted. Blood reflow during the first heartbeat period after applying the secondary pressure of 40mmHg was (mean±SD) 0.059±0.05%mm for scleroderma patients and 0.173±0.104%mm for healthy volunteers. Blood reflow was significantly lower in scleroderma patients than in healthy volunteers (p<0.05). This result indicates that the information necessary for assessing blood circulation disorder of peripheral blood vessels in scleroderma patients is objectively obtained by the proposed method.
Active Exhaust Silencing Systen For the Management of Auxillary Power Unit Sound Signatures
2014-08-01
conceptual mass-less pistons are introduced into the system before and after the injection site, such that they will move exactly with the plane wave...Unit Sound Signatures, Helminen, et al. Page 2 of 7 either the primary source or the injected source. It is assumed that the pistons are ‘close...source, it causes both pistons to move identically. The pressures induced by the flow on the pistons do not affect the flow generated by the
NASA Astrophysics Data System (ADS)
Huo, Lin; Cheng, Xing-Hua; Yang, Tao
2015-05-01
This paper presents a study of aerothermoelastic response of a C/SiC panel, which is a primary structure for ceramic matrix composite shingle thermal protection system for hypersonic vehicles. It is based on a three dimensional thermal protection shingle panel on a quasi-waverider vehicle model. Firstly, the Thin Shock Layer and piston theory are adopted to compute the aerodynamic pressure of rigid body and deformable body, and a series of engineering methods are used to compute the aerodynamic heating. Then an aerothermoelastic loosely-coupled time marching strategy and self-adapting aerodynamic heating time step are developed to analyze the aerothermoelastic response of the panel, with an aerodynamic heating and temperature field coupling parameter selection method being adopted to increase the efficiency. Finally, a few revealing conclusions are reached by analyzing how coupling at different degrees influences the quasi-static aerothermoelastic response of the panel and how aerodynamic pressure of rigid body time step influences the quasi-static aerothermoelastic response on a glide trajectory.
Multi-sensor Array for High Altitude Balloon Missions to the Stratosphere
NASA Astrophysics Data System (ADS)
Davis, Tim; McClurg, Bryce; Sohl, John
2008-10-01
We have designed and built a microprocessor controlled and expandable multi-sensor array for data collection on near space missions. Weber State University has started a high altitude research balloon program called HARBOR. This array has been designed to data log a base set of measurements for every flight and has room for six guest instruments. The base measurements are absolute pressure, on-board temperature, 3-axis accelerometer for attitude measurement, and 2-axis compensated magnetic compass. The system also contains a real time clock and circuitry for logging data directly to a USB memory stick. In typical operation the measurements will be cycled through in sequence and saved to the memory stick along with the clock's time stamp. The microprocessor can be reprogrammed to adapt to guest experiments with either analog or digital interfacing. This system will fly with every mission and will provide backup data collection for other instrumentation for which the primary task is measuring atmospheric pressure and temperature. The attitude data will be used to determine the orientation of the onboard camera systems to aid in identifying features in the images. This will make these images easier to use for any future GIS (geographic information system) remote sensing missions.
A CFD Study of Turbojet and Single-Throat Ramjet Ejector Interaction
NASA Technical Reports Server (NTRS)
Chang, Ing; Hunter, Louis
1996-01-01
Supersonic ejector-diffuse systems have application in driving an advanced airbreathing propulsion system, consisting of turbojet engines acting as the primary and a single throat ramjet acting as the secondary. The turbojet engines are integrated into the single throat ramjet to minimize variable geometry and eliminate redundant propulsion components. The result is a simple, lightweight system that is operable from takeoff to high Mach numbers. At this high Mach number (approximately Mach 3.0), the turbojets are turned off and the high speed ramjet/scramjet take over and drive the vehicle to Mach 6.0. The turbojet-ejector-ramjet system consists of nonafterburning turbojet engines with ducting canted at 20 degrees to supply supersonic flow (downstream of CD nozzle) to the horizontal ramjet duct at a supply total pressure and temperature. Two conditions were modelled by a 2-D full Navier Stokes code at Mach 2.0. The code modelled the Fabri choke as well as the non-Fabri non critical case, using a computational throat to supply the back pressure. The results, which primarily predict the secondary mass flow rate and the mixed conditions at the ejector exit were in reasonable agreement with the 1-D cycle code (TBCC).
Nanobubbles: a new paradigm for air-seeding in xylem.
Schenk, H Jochen; Steppe, Kathy; Jansen, Steven
2015-04-01
Long-distance water transport in plants relies on a system that typically operates under negative pressure and is prone to hydraulic failure due to gas bubble formation. One primary mechanism of bubble formation takes place at nanoporous pit membranes between neighboring conduits. We argue that this process is likely to snap off nanobubbles because the local increase in liquid pressure caused by entry of air-water menisci into the complex pit membrane pores would energetically favor nanobubble formation over instant cavitation. Nanobubbles would be stabilized by surfactants and by gas supersaturation of the sap, may dissolve, fragment into smaller bubbles, or create embolisms. The hypothesis that safe and stable nanobubbles occur in plants adds a new component supporting the cohesion-tension theory. Copyright © 2015 Elsevier Ltd. All rights reserved.
Fish allergy causing angioedema and secondary angle-closure glaucoma.
Calder, Donovan; Calder, Jennifer
2013-03-06
A 56-year-old woman with a history of primary angle-closure glaucoma presented with acute generalised swelling, and facial angioedema following a fish meal. She complained of nausea, vomiting, headache, pain in both eyes and acute loss of vision. Her visual acuity was reduced and intraocular pressures (IOP) were elevated. Gonioscopy revealed complete angle closure in the left eye and complete to partial closure in the right eye. Through existing peripheral iridotomies the anterior capsules were seen pressed up against the iris of both eyes. A diagnosis of angle-closure glaucoma was made, medications were started to reduce the elevated intraocular pressure and systemic antihistamine to counter the allergic reaction. She was hospitalised for further management. A follow-up at 2 years revealed her visual acuities and IOP had remained normal.
Inverse time-of-flight spectrometer for beam plasma research
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yushkov, Yu. G., E-mail: yuyushkov@gmail.com; Zolotukhin, D. B.; Tyunkov, A. V.
2014-08-15
The paper describes the design and principle of operation of an inverse time-of-flight spectrometer for research in the plasma produced by an electron beam in the forevacuum pressure range (5–20 Pa). In the spectrometer, the deflecting plates as well as the drift tube and the primary ion beam measuring system are at high potential with respect to ground. This provides the possibility to measure the mass-charge constitution of the plasma created by a continuous electron beam with a current of up to 300 mA and electron energy of up to 20 keV at forevacuum pressures in the chamber placed atmore » ground potential. Research results on the mass-charge state of the beam plasma are presented and analyzed.« less
Sanderson, D J; Hennig, E M; Black, A H
2000-03-01
The aim of this study was to determine the response of cyclists to manipulations of cadence and power output in terms of force application and plantar pressure distribution. Two groups of cyclists, 17 recreational and 12 competitive, rode at three nominal cadences (60, 80, 100 rev x min(-1)) and four power outputs (100, 200, 300, 400 W) while simultaneous force and in-shoe pressure data were collected. Two piezoelectric triaxial force transducers mounted in the right pedal measured components of the pedal force and orientation, and a discrete transducer system with 12 transducers recorded the in-shoe pressures. Force application was characterized by calculating peak resultant and peak effective pedal forces and positive and negative impulses. In-shoe pressures were analysed as peak pressures and as the percent relative load. The force data showed no significant group effect but there was a cadence and power main effect. The impulse data showed a significant three-way interaction. Increased cadence resulted in a decreased positive impulse, while increased power output resulted in an increased impulse. The competitive group produced less positive impulse but the difference became less at higher cadences. Few between-group differences were found in pressure, notable only in the pressure under the first metatarsal region. This showed a consistent pattern of in-shoe pressure distribution, where the primary loading structures were the first metatarsal and hallux. There was no indication that pressure at specific sites influenced the pedal force application. The absence of group differences indicated that pressure distribution was not the result of training, but reflected the intrinsic relationship between the foot, the shoe and the pedal.
Thirty-Minute Office Blood Pressure Monitoring in Primary Care
Bos, Michiel J.; Buis, Sylvia
2017-01-01
PURPOSE Automated office blood pressure monitoring during 30 minutes (OBP30) may reduce overtreatment of patients with white-coat hypertension in primary health care. OBP30 results approximate those of ambulatory blood pressure monitoring, but OBP30 is much more convenient. In this study, we compared OBP30 with routine office blood pressure (OBP) readings for different indications in primary care and evaluated how OBP30 influenced the medication prescribing of family physicians. METHODS All consecutive patients who underwent OBP30 for medical reasons over a 6-month period in a single primary health care center in the Netherlands were enrolled. We compared patients’ OBP30 results with their last preceding routine OBP reading, and we asked their physicians why they ordered OBP30, how they treated their patients, and how they would have treated their patients without it. RESULTS We enrolled 201 patients (mean age 68.6 years, 56.7% women). The mean systolic OBP30 was 22.8 mm Hg lower than the mean systolic OBP (95% CI, 19.8–26.1 mm Hg). The mean diastolic OBP30 was 11.6 mm Hg lower than the mean diastolic OBP (95% CI, 10.2–13.1 mm Hg). Considerable differences between OBP and OBP30 existed in patients with and without suspected white-coat hypertension, and differences were larger in individuals aged 70 years or older. Based on OBP alone, physicians said they would have started or intensified medication therapy in 79.1% of the studied cases (95% CI, 73.6%–84.6%). In fact, with the results of OBP30 available, physicians started or intensified medication therapy in 24.9% of cases (95% CI, 18.9%–30.9%). CONCLUSIONS OBP30 yields considerably lower blood pressure readings than OBP in all studied patient groups. OBP30 is a promising technique to reduce overtreatment of white-coat hypertension in primary health care. PMID:28289110
Design principles of a simple and safe 200-MW(thermal) nuclear district heating plant
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goetzmann, C.; Bittermann, D.; Gobel, A.
Kraftwerk Union AG has almost completed the development of a dedicated 200-MW(thermal) nuclear district heating plant to provide environmentally clean energy at a predictably low cost. The concept can easily be adapted to meet power requirements within the 100- to 500-MW(thermal) range. This technology is the product of the experience gained with large pressurized water reactor and boiling water reactor power plants, with respect to both plant and fuel performance. The major development task is that of achieving sufficiently low capital cost by tailoring components and systems designed for large plants to the specific requirements of district heating. These requirementsmore » are small absolute power, low temperatures and pressures, and modest load following, all of which result in the characteristics that are summarized. A fully integrated primary system with natural circulation permits a very compact reactor building containing all safety-related systems and components. Plant safety is essentially guaranteed by inherent features. The reactor containment is tightly fitted around the reactor pressure vessel in such a way that, in the event of any postulated coolant leak, the core cannot become uncovered, even temporarily. Shutdown is assured by gravity drop of the control rods mounted above the core. Decay heat is removed from the core by means of natural circulation via dedicated intermediate circuits of external aircoolers.« less
A Proposed Dynamic Pressure and Temperature Primary Standard
Rosasco, Gregory J.; Bean, Vern E.; Hurst, Wilbur S.
1990-01-01
Diatomic gas molecules have a fundamental vibrational motion whose frequency is affected by pressure in a simple way. In addition, these molecules have well defined rotational energy levels whose populations provide a reliable measure of the thermodynamic temperature. Since information concerning the frequency of vibration and the relative populations can be determined by laser spectroscopy, the gas molecules themselves can serve as sensors of pressure and temperature. Through measurements under static conditions, the pressure and temperature dependence of the spectra of selected molecules is now understood. As the time required for the spectroscopic measurement can be reduced to nanoseconds, the diatomic gas molecule is an excellent candidate for a dynamic pressure/temperature primary standard. The temporal response in this case will be limited by the equilibration time for the molecules to respond to changes in local thermodynamic variables. Preliminary feasibility studies suggest that by using coherent anti-Stokes Raman spectroscopy we will be able to measure dynamic pressure up to 108 Pa and dynamic temperature up to 1500 K with an uncertainty of 5%. PMID:28179756
Azuara-Blanco, Augusto; Burr, Jennifer; Ramsay, Craig; Cooper, David; Foster, Paul J; Friedman, David S; Scotland, Graham; Javanbakht, Mehdi; Cochrane, Claire; Norrie, John
2016-10-01
Primary angle-closure glaucoma is a leading cause of irreversible blindness worldwide. In early-stage disease, intraocular pressure is raised without visual loss. Because the crystalline lens has a major mechanistic role, lens extraction might be a useful initial treatment. From Jan 8, 2009, to Dec 28, 2011, we enrolled patients from 30 hospital eye services in five countries. Randomisation was done by a web-based application. Patients were assigned to undergo clear-lens extraction or receive standard care with laser peripheral iridotomy and topical medical treatment. Eligible patients were aged 50 years or older, did not have cataracts, and had newly diagnosed primary angle closure with intraocular pressure 30 mm Hg or greater or primary angle-closure glaucoma. The co-primary endpoints were patient-reported health status, intraocular pressure, and incremental cost-effectiveness ratio per quality-adjusted life-year gained 36 months after treatment. Analysis was by intention to treat. This study is registered, number ISRCTN44464607. Of 419 participants enrolled, 155 had primary angle closure and 263 primary angle-closure glaucoma. 208 were assigned to clear-lens extraction and 211 to standard care, of whom 351 (84%) had complete data on health status and 366 (87%) on intraocular pressure. The mean health status score (0·87 [SD 0·12]), assessed with the European Quality of Life-5 Dimensions questionnaire, was 0·052 higher (95% CI 0·015-0·088, p=0·005) and mean intraocular pressure (16·6 [SD 3·5] mm Hg) 1·18 mm Hg lower (95% CI -1·99 to -0·38, p=0·004) after clear-lens extraction than after standard care. The incremental cost-effectiveness ratio was £14 284 for initial lens extraction versus standard care. Irreversible loss of vision occurred in one participant who underwent clear-lens extraction and three who received standard care. No patients had serious adverse events. Clear-lens extraction showed greater efficacy and was more cost-effective than laser peripheral iridotomy, and should be considered as an option for first-line treatment. Medical Research Council. Copyright © 2016 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY license. Published by Elsevier Ltd.. All rights reserved.
Mineralocorticoid Receptor Activation Contributes to the Supine Hypertension of Autonomic Failure.
Arnold, Amy C; Okamoto, Luis E; Gamboa, Alfredo; Black, Bonnie K; Raj, Satish R; Elijovich, Fernando; Robertson, David; Shibao, Cyndya A; Biaggioni, Italo
2016-02-01
Primary autonomic failure is characterized by disabling orthostatic hypotension, but at least half of these patients have paradoxical supine hypertension. Renin-angiotensin mechanisms were not initially thought to contribute to this hypertension because plasma renin activity is often undetectable in autonomic failure. Plasma aldosterone levels are normal, however, and we recently showed that plasma angiotensin II is elevated and acts at AT1 (angiotensin type 1) receptors to contribute to hypertension in these patients. Because aldosterone and angiotensin II can also bind mineralocorticoid receptors to elevate blood pressure, we hypothesized that mineralocorticoid receptor activation plays a role in the hypertension of autonomic failure. To test this hypothesis, we determined the acute effects of the mineralocorticoid receptor antagonist eplerenone (50 mg, oral) versus placebo on supine blood pressure in a randomized, double-blind, crossover study. Medications were given at 8:00 pm with blood pressure recorded every 2 hours for 12 hours. Ten primary autonomic failure patients with supine hypertension completed this study (7 pure autonomic failure, 2 multiple system atrophy, 1 parkinson's disease; 7 male; 70±2 years of age). Eplerenone maximally reduced supine systolic blood pressure by 32±6 mm Hg at 8 hours after administration (versus 8±10 mm Hg placebo, P=0.016), with no effect on nocturia (12-hour urine volume: 985±134 mL placebo versus 931±94 mL eplerenone, P=0.492; nocturnal weight loss: -1.19±0.15 kg placebo versus -1.18±0.15 kg eplerenone, P=0.766). These findings suggest that inappropriate mineralocorticoid receptor activation contributes to the hypertension of autonomic failure, likely independent of canonical mineralocorticoid effects, and provides rationale for use of eplerenone in these patients. © 2015 American Heart Association, Inc.
Effect of high pressure on the photochemical reaction center from Rhodobacter sphaeroides R26.1.
Gall, A; Ellervee, A; Bellissent-Funel, M C; Robert, B; Freiberg, A
2001-01-01
High-pressure studies on the photochemical reaction center from the photosynthetic bacterium Rhodobacter sphaeroides, strain R26.1, shows that, up to 0.6 GPa, this carotenoid-less membrane protein does not loose its three-dimensional structure at room temperature. However, as evidenced by Fourier-transform preresonance Raman and electronic absorption spectra, between the atmospheric pressure and 0.2 GPa, the structure of the bacterial reaction center experiences a number of local reorganizations in the binding site of the primary electron donor. Above that value, the apparent compressibility of this membrane protein is inhomogeneous, being most noticeable in proximity to the bacteriopheophytin molecules. In this elevated pressure range, no more structural reorganization of the primary electron donor binding site can be observed. However, its electronic structure becomes dramatically perturbed, and the oscillator strength of its Q(y) electronic transition drops by nearly one order of magnitude. This effect is likely due to very small, pressure-induced changes in its dimeric structure. PMID:11222309
Effect of cavitation in high-pressure direct injection
NASA Astrophysics Data System (ADS)
Aboulhasanzadeh, Bahman; Johnsen, Eric
2015-11-01
As we move toward higher pressures for Gasoline Direct Injection and Diesel Direct Injection, cavitation has become an important issue. To better understand the effect of cavitation on the nozzle flow and primary atomization, we use a high-order accurate Discontinuous Galerkin approach using multi-GPU parallelism to simulate the compressible flow inside and outside the nozzle. Phase change is included using the six-equations model. We investigate the effect of nozzle geometry on cavitation inside the injector and on primary atomization outside the nozzle.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-25
... operating pressures, leakage from primary water stress corrosion cracking below the proposed limited... discussed in Regulatory Guide (RG) 1.121, ``Bases for Plugging Degraded PWR [Pressurized-Water Reactor...
Hibler, Susanne; Wagner, Christophe; Gieseler, Henning
2012-01-01
In a previous study, heat transfer coefficients of different 10 mL tubing and molded vials were determined gravimetrically via sublimation tests with pure water. Contrary to "conventional wisdom", only small differences in K(v) values between tubing and molded vials were found in the pressure range relevant for pharmaceutical freeze-drying. In order to investigate the impact of these relatively small differences on the primary drying time of an actual product, freeze-drying experiments with 5% gentamicin sulfate solution as a model system were performed at 68, 100 and 200 mTorr. The primary drying times of the API in recently developed molded (EasyLyo™), tubing (TopLyo™) and polymer vials (TopPac™) were compared. At 68 and 100 mTorr the primary drying time of the drug in the glass vials only differed by 3% to 4%, while the polymer vial took around 9% longer. At 200 mTorr, the API in the EasyLyo™ vials dried approximately 15% faster compared to the other vial types. The present study suggest that molded vials that have been modified in design to have better heat transfer properties can achieve drying times comparable to tubing vials.
Vacuum generation in pneumatic artificial heart drives with a specially designed ejector system.
Schima, H; Huber, L; Spitaler, F
1990-06-01
To improve the filling characteristics of pneumatically driven membrane artificial hearts (AHs), a vacuum is applied during diastole. This paper describes an ejector system for AH-drivers based on the Venturi effect, which was designed for this purpose. It provides vacuums of more than -40 mmHg at flow rates up to 50 l/min requiring a supplying primary gas pressure of less than 150 kPa (1140 mmHg). Under normal working conditions, the necessary supply flow was less than 5l/min. The device is small, cheap, quiet and fail-safe, and has been evaluated successfully in experimental and clinical use.
Hormonal regulation of fluid and electrolyte metabolism in zero-g and bedrest
NASA Technical Reports Server (NTRS)
Vernikos, Joan
1991-01-01
The study of man in spaceflight has consistently indicated changes in fluid and electrolyte balance. Sodium (Na), Potassium (K), and Calcium (Ca) excretion are increased, accompanied by changes in the levels and responsiveness of adrenal hormones and the sympathetic nervous system (SNS). These hormones and neurohumors are critical to the regulation of blood pressure, blood flow, and blood volume. The primary objectives of the research conducted under this task have been to use -6 deg head down bedrest (BR) as the analog to spaceflight, to determine the long term changes in these systems, their relationship to orthostatic tolerance, and to develop and test suitable countermeasures.
ATC contingency operations in the en-route flight regime
NASA Technical Reports Server (NTRS)
Lyman, E. G.
1981-01-01
Air traffic control (ATC) operations were examined to learn what factors of controller performance should be given consideration in the design and development of future automation systems enhancing ATC. Contingencies were of two types: those constraining airspace usage or traffic flow (i.e., weather); and those related to system and equipment usage (i.e., radar/radio status). Examination of controller response to contingencies and workload pressures showed differing effects on controller allocations of effort among the three primary function of planning, monitoring, and informaton transfer. Automation advancements oriented towards aiding the controller in performing monitoring tasks may offer the most substantial safety benefit.
Design and implementation of a simple nuclear power plant simulator
NASA Astrophysics Data System (ADS)
Miller, William H.
1983-02-01
A simple PWR nuclear power plant simulator has been designed and implemented on a minicomputer system. The system is intended for students use in understanding the power operation of a nuclear power plant. A PDP-11 minicomputer calculates reactor parameters in real time, uses a graphics terminal to display the results and a keyboard and joystick for control functions. Plant parameters calculated by the model include the core reactivity (based upon control rod positions, soluble boron concentration and reactivity feedback effects), the total core power, the axial core power distribution, the temperature and pressure in the primary and secondary coolant loops, etc.
Description of the insulation system for the Langley 0.3-Meter Transonic Cryogenic Tunnel
NASA Technical Reports Server (NTRS)
Lawing, P. L.; Dress, D. A.; Kilgore, R. A.
1985-01-01
The thermal insulation system of the Langley 0.3 Meter Transonic Cryogenic Tunnel is described. The insulation system is designed to operate from room temperature down to about 77.4 K, the temperature of liquid nitrogen at 1 atmosphere. A detailed description is given of the primary insulation sytem consists of glass fiber mats, a three part vapor barrier, and a dry positive pressure purge system. Also described are several secondary insulation systems required for the test section, actuators, and tunnel supports. An appendix briefly describes the original insulation system which is considered inferior to the one presently in place. The time required for opening and closing portions of the insulation system for modification or repair to the tunnel has been reduced, typically, from a few days for the original thermal insulating system to a few hours for the present system.
Ouelaa, Wassila; Ghouzali, Ibtissem; Langlois, Ludovic; Fetissov, Serguei; Déchelotte, Pierre; Ducrotté, Philippe; Leroi, Anne Marie; Gourcerol, Guillaume
2012-01-01
Background & Aims Gastric electrical stimulation (GES) is an effective therapy to treat patients with chronic dyspepsia refractory to medical management. However, its mechanisms of action remain poorly understood. Methods Gastric pain was induced by performing gastric distension (GD) in anesthetized rats. Pain response was monitored by measuring the pseudo-affective reflex (e.g., blood pressure variation), while neuronal activation was determined using c-fos immunochemistry in the central nervous system. Involvement of primary afferents was assessed by measuring phosphorylation of ERK1/2 in dorsal root ganglia. Results GES decreased blood pressure variation induced by GD, and prevented GD-induced neuronal activation in the dorsal horn of the spinal cord (T9–T10), the nucleus of the solitary tract and in CRF neurons of the hypothalamic paraventricular nucleus. This effect remained unaltered within the spinal cord when sectioning the medulla at the T5 level. Furthermore, GES prevented GD-induced phosphorylation of ERK1/2 in dorsal root ganglia. Conclusions GES decreases GD-induced pain and/or discomfort likely through a direct modulation of gastric spinal afferents reducing central processing of visceral nociception. PMID:23284611
FRIB Cryogenic Distribution System and Status
NASA Astrophysics Data System (ADS)
Ganni, V.; Dixon, K.; Laverdure, N.; Yang, S.; Nellis, T.; Jones, S.; Casagrande, F.
2015-12-01
The MSU-FRIB cryogenic distribution system supports the 2 K primary, 4 K primary, and 35 - 55 K shield operation of more than 70 loads in the accelerator and the experimental areas. It is based on JLab and SNS experience with bayonet-type disconnects between the loads and the distribution system for phased commissioning and maintenance. The linac transfer line, which features three separate transfer line segments for additional independence during phased commissioning at 4 K and 2 K, connects the folded arrangement of 49 cryomodules and 4 superconducting dipole magnets and a fourth transfer line supports the separator area cryo loads. The pressure reliefs for the transfer line process lines, located in the refrigeration room outside the tunnel/accelerator area, are piped to be vented outdoors. The transfer line designs integrate supply and return flow paths into a combined vacuum space. The main linac distribution segments are produced in a small number of standard configurations; a prototype of one such configuration has been fabricated at Jefferson Lab and has been installed at MSU to support testing of a prototype FRIB cryomodule.
Traumatic brain injury: an overview of pathobiology with emphasis on military populations
Cernak, Ibolja; Noble-Haeusslein, Linda J
2010-01-01
This review considers the pathobiology of non-impact blast-induced neurotrauma (BINT). The pathobiology of traumatic brain injury (TBI) has been historically studied in experimental models mimicking features seen in the civilian population. These brain injuries are characterized by primary damage to both gray and white matter and subsequent evolution of secondary pathogenic events at the cellular, biochemical, and molecular levels, which collectively mediate widespread neurodegeneration. An emerging field of research addresses brain injuries related to the military, in particular blast-induced brain injuries. What is clear from the effort to date is that the pathobiology of military TBIs, particularly BINT, has characteristics not seen in other types of brain injury, despite similar secondary injury cascades. The pathobiology of primary BINT is extremely complex. It comprises systemic, local, and cerebral responses interacting and often occurring in parallel. Activation of the autonomous nervous system, sudden pressure-increase in vital organs such as lungs and liver, and activation of neuroendocrine-immune system are among the most important mechanisms significantly contributing to molecular changes and cascading injury mechanisms in the brain. PMID:19809467
Advanced nozzle and engine components test facility
NASA Technical Reports Server (NTRS)
Beltran, Luis R.; Delroso, Richard L.; Delrosario, Ruben
1992-01-01
A test facility for conducting scaled advanced nozzle and engine component research is described. The CE-22 test facility, located in the Engine Research Building of the NASA Lewis Research Center, contains many systems for the economical testing of advanced scale-model nozzles and engine components. The combustion air and altitude exhaust systems are described. Combustion air can be supplied to a model up to 40 psig for primary air flow, and 40, 125, and 450 psig for secondary air flow. Altitude exhaust can be simulated up to 48,000 ft, or the exhaust can be atmospheric. Descriptions of the multiaxis thrust stand, a color schlieren flow visualization system used for qualitative flow analysis, a labyrinth flow measurement system, a data acquisition system, and auxiliary systems are discussed. Model recommended design information and temperature and pressure instrumentation recommendations are included.
Fast reactor power plant design having heat pipe heat exchanger
Huebotter, P.R.; McLennan, G.A.
1984-08-30
The invention relates to a pool-type fission reactor power plant design having a reactor vessel containing a primary coolant (such as liquid sodium), and a steam expansion device powered by a pressurized water/steam coolant system. Heat pipe means are disposed between the primary and water coolants to complete the heat transfer therebetween. The heat pipes are vertically oriented, penetrating the reactor deck and being directly submerged in the primary coolant. A U-tube or line passes through each heat pipe, extended over most of the length of the heat pipe and having its walls spaced from but closely proximate to and generally facing the surrounding walls of the heat pipe. The water/steam coolant loop includes each U-tube and the steam expansion device. A heat transfer medium (such as mercury) fills each of the heat pipes. The thermal energy from the primary coolant is transferred to the water coolant by isothermal evaporation-condensation of the heat transfer medium between the heat pipe and U-tube walls, the heat transfer medium moving within the heat pipe primarily transversely between these walls.
Fast reactor power plant design having heat pipe heat exchanger
Huebotter, Paul R.; McLennan, George A.
1985-01-01
The invention relates to a pool-type fission reactor power plant design having a reactor vessel containing a primary coolant (such as liquid sodium), and a steam expansion device powered by a pressurized water/steam coolant system. Heat pipe means are disposed between the primary and water coolants to complete the heat transfer therebetween. The heat pipes are vertically oriented, penetrating the reactor deck and being directly submerged in the primary coolant. A U-tube or line passes through each heat pipe, extended over most of the length of the heat pipe and having its walls spaced from but closely proximate to and generally facing the surrounding walls of the heat pipe. The water/steam coolant loop includes each U-tube and the steam expansion device. A heat transfer medium (such as mercury) fills each of the heat pipes. The thermal energy from the primary coolant is transferred to the water coolant by isothermal evaporation-condensation of the heat transfer medium between the heat pipe and U-tube walls, the heat transfer medium moving within the heat pipe primarily transversely between these walls.
Meaume, S; Marty, M
2015-08-01
Specialised pressure-relieving supports reduce or relieve the interface pressure between the skin and the support surface. The comparative effectiveness of dynamic support surfaces is debated. The aim of this study is to examine the impact of using an alternating pressure air mattress (APAM) on pressure ulcer (PU) incidence in patients receiving home-based care. A second aim was to determine the level of patient/family satisfaction with comfort and gain the views of the care team that used the APAM. The PARESTRY study was a prospective observational study conducted in patients with a high risk of PUs (Braden score <15), discharged to hospital-care at home. The primary prevention groups consisted of patients with no PU at baseline who were in bed for at least 20 hours a day. Patients at baseline with a category 3 or 4 PU or a category 1 or 2 PU in association with poor general health or end-of-life status were included in the secondary prevention group. All patients were laid on an APAM. The primary end point was the % of patients with a worsening skin condition in the pressure area (heel, sacrum, ischium) at day 90 or at the end of the study. The primary analysis was done on the full analysis set (patients included with at least a second assessment), using the last observation carried forward technique to handle missing data, at day 90. A 95% confidence interval was calculated. Analysis was performed on 92 patients (30 in primary prevention and 62 in secondary prevention). The average time spent in bed was 22.7 (SD 2.7) hours a day and 22.6 (SD 2.2) hours in the primary and secondary prevention groups, respectively. At baseline, in the secondary group, 77% of patients had a sacral PU, 63% a heel PU, 8% an ischial tuberosity PU and 45% a PU in another area, a number of patients having multiple PUs. In the primary prevention group, 63% (19/30) of patients dropped out of the study (5 were hospitalised, 9 died, 5 other causes). In the secondary prevention group, 61% (38/62) dropped out (7 were hospitalised, 23 died, 8 others causes). In the primary prevention group, only one patient had worsening skin condition. In the secondary prevention group, 17.7% (11/62: 95% CI: 8.3-27.2) of patients had worsening skin condition. The number of PUs decreased regardless of location. At the end of follow-up, 49% (45/92) of patients had a PU versus 67% (62/92) at baseline This work provides data on the incidence of PUs in patients at high risk, who are using APAMs, and, following inpatient hospitalisation, are taken into home health-care centres. The results of the study highlight the importance of continuity of care across transitions between care settings.
Recent Electric Propulsion Development Activities for NASA Science Missions
NASA Technical Reports Server (NTRS)
Pencil, Eric J.
2009-01-01
(The primary source of electric propulsion development throughout NASA is managed by the In-Space Propulsion Technology Project at the NASA Glenn Research Center for the Science Mission Directorate. The objective of the Electric Propulsion project area is to develop near-term electric propulsion technology to enhance or enable science missions while minimizing risk and cost to the end user. Major hardware tasks include developing NASA s Evolutionary Xenon Thruster (NEXT), developing a long-life High Voltage Hall Accelerator (HIVHAC), developing an advanced feed system, and developing cross-platform components. The objective of the NEXT task is to advance next generation ion propulsion technology readiness. The baseline NEXT system consists of a high-performance, 7-kW ion thruster; a high-efficiency, 7-kW power processor unit (PPU); a highly flexible advanced xenon propellant management system (PMS); a lightweight engine gimbal; and key elements of a digital control interface unit (DCIU) including software algorithms. This design approach was selected to provide future NASA science missions with the greatest value in mission performance benefit at a low total development cost. The objective of the HIVHAC task is to advance the Hall thruster technology readiness for science mission applications. The task seeks to increase specific impulse, throttle-ability and lifetime to make Hall propulsion systems applicable to deep space science missions. The primary application focus for the resulting Hall propulsion system would be cost-capped missions, such as competitively selected, Discovery-class missions. The objective of the advanced xenon feed system task is to demonstrate novel manufacturing techniques that will significantly reduce mass, volume, and footprint size of xenon feed systems over conventional feed systems. This task has focused on the development of a flow control module, which consists of a three-channel flow system based on a piezo-electrically actuated valve concept, as well as a pressure control module, which will regulate pressure from the propellant tank. Cross-platform component standardization and simplification are being investigated through the Standard Architecture task to reduce first user costs for implementing electric propulsion systems. Progress on current hardware development, recent test activities and future plans are discussed.