Study on clearance system

International Nuclear Information System (INIS)

Onishi, Yuko; Miura, Hiroshi; Kawasaki, Satoru

2011-01-01

The clearance system is a legal system to release 'the radioactive waste not requiring treatment as radioactive waste' from the regulatory control. JNES supports NISA on approval and confirmation of clearance measurement and judgment developed by the operator. The objective of this study is to establish technical base of the validation method of the clearance measurement for various objects. In reactor facilities, the bulk measurement technique or the statistical sampling measurement technique may be applied to large scale objects or concrete walls. In this study, the criteria of those techniques were examined. In uranium processing facilities, it is important to confirm surface state of the object in case of detecting alpha rays. The result of the examination about the influence of the surface rust in the uranium clearance measurement by the alpha ray measurement showed that the pollution was distributed in rust layer uniformly. This result will be reflected to the revision of the Ministerial Ordinance on Clearance in 2011FY. To develop a manual for unexpected incidents, the response procedure for an unexpected incident was prepared, including a response system. (author)

Towards Safe Navigation by Formalizing Navigation Rules

Directory of Open Access Journals (Sweden)

Arne Kreutzmann

2013-06-01

Full Text Available One crucial aspect of safe navigation is to obey all navigation regulations applicable, in particular the collision regulations issued by the International Maritime Organization (IMO Colregs. Therefore, decision support systems for navigation need to respect Colregs and this feature should be verifiably correct. We tackle compliancy of navigation regulations from a perspective of software verification. One common approach is to use formal logic, but it requires to bridge a wide gap between navigation concepts and simple logic. We introduce a novel domain specification language based on a spatio-temporal logic that allows us to overcome this gap. We are able to capture complex navigation concepts in an easily comprehensible representation that can direcly be utilized by various bridge systems and that allows for software verification.

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... to loosen mucus from airway walls. See how different airway clearance techniques work to help you clear the thick, sticky mucus ... Offer their tips for fitting ACTs into daily life Airway Clearance Techniques | Webcast ... Facebook Twitter ...

Evaluation of serum iohexol clearance for use in predicting carboplatin clearance in cats.

Science.gov (United States)

Bailey, Dennis B; Rassnick, Kenneth M; Prey, Joshua D; Dykes, Nathan L

2009-09-01

To determine whether a glomerular filtration rate (GFR) assay based on serum iohexol clearance can be used to predict carboplatin clearance in cats. 10 cats with tumors. GFR was measured concurrently by use of plasma clearance of technetium Tc 99m-labeled diethylenetriaminepentaacetic acid ((99m)Tc-DTPA) to yield GFR(99mTc-DTPA) and serum clearance of iohexol to yield GFR(Iohexol). A single dose of carboplatin was administered IV as a bolus. Dose was calculated by use of a target value for the area under the plasma platinum concentration-versus-time curve (AUC(Target)) and estimation of platinum clearance (CL(PT)) derived from GFR(99mTc-DTPA) as follows: dose = AUC(Target) x 2.6 x GFR(99mTc-DTPA) x body weight, where AUC(Target) is 2.75 min.mg.mL(-1). Plasma platinum concentrations were measured via atomic absorption spectrophotometry. Values for GFR(99mTc-DTPA) and GFR(Iohexol) were compared by use of least-squares regression and Bland-Altman analysis. Least-squares regression was used to determine whether CL(PT) could be predicted from GFR(99mTc-DTPA) or GFR(Iohexol) (or both). GFR(99mTc-DTPA) and GFR(Iohexol) were strongly correlated (r = 0.90), but GFR(Iohexol) values were significantly larger by a factor of approximately 1.4. Platinum clearance had a significant linear relationship to GFR(99mTc-DTPA) (CL(PT) = 2.5 x GFR(99mTc-DTPA)) and to GFR(Iohexol) (CL(PT) = [1.3 x GFR(Iohexol)] + 1.4). In cats, serum iohexol clearance was an accurate predictor of CL(PT) and can be used to calculate the carboplatin dose as follows: dose = AUC(Target) x ([1.3 x GFR(Iohexol)] + 1.4) x body weight.

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... and Their Families When There's More Than One Person With CF in the Same School Daily Life ... Awards and Grants Career Development Awards Research Awards Training Awards CF ... Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Team Your cystic fibrosis care team includes a group of CF health care professionals who partner with ... Awards and Grants Career Development Awards Research Awards Training Awards CF ... Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your ...

Clearance Kinetics and Clearance Routes of Molecules From the Suprachoroidal Space After Microneedle Injection.

Science.gov (United States)

Chiang, Bryce; Wang, Ke; Ethier, C Ross; Prausnitz, Mark R

2017-01-01

To determine clearance kinetics and routes of clearance of molecules from the suprachoroidal space (SCS) of live New Zealand White rabbits. Suprachoroidal space collapse rate and pressure changes after microneedle injection into SCS were determined. Fluorescent fundus images were acquired to determine clearance rates of molecules ranging in size from 332 Da to 2 MDa. Microneedle injections of fluorescein were performed, and samples were taken from various sites over time to determine amount of fluorescein exiting the eye. Clearance transport was modeled theoretically and compared with experimental data. After injection, pressures in SCS and vitreous humor spiked and returned to baseline within 20 minutes; there was no difference between these two pressures. Suprachoroidal space collapse occurred within 40 minutes. One hour after fluorescein injection, 46% of fluorescein was still present in the eye, 15% had transported across sclera, 6% had been cleared by choroidal vasculature, and 4% had exited via leakage pathways. Characteristic clearance time increased in proportion with molecular radius, but total clearance of 2 MDa FITC-dextran was significantly slower (21 days) than smaller molecules. These data generally agreed with predictions from a theoretical model of molecular transport. Guided by experimental data in the context of model predictions, molecular clearance from SCS occurred in three regimes: (1) on a time scale of approximately 10 minutes, fluid and molecules exited SCS by diffusion into sclera and choroid, and by pressure-driven reflux via transscleral leakage sites; (2) in approximately 1 hour, molecules cleared from choroid by blood flow; and (3) in 1 to 10 hours, molecules cleared from sclera by diffusion and convection.

Study on clearance system

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-08-15

The clearance system is a legal system to release 'the radioactive waste not requiring treatment as radioactive waste' from the regulatory control. JNES supports Nuclear Regulatory Agency on approval and confirmation of clearance measurement and judgment developed by the operator. The objective of this study is to establish technical base of the validation method of the clearance measurement for various objects. In uranium processing facilities, simulation sources emitting alpha-rays is used in a validity confirmation examination of the measuring equipment. In this study, these sources were examined by measuring alpha and beta spectra to evaluate the applicability and problem of these sources. In addition, the measuring method detecting gamma-rays was examined. This method can be applied to complicated objects. As a part to develop a manual for unexpected incidents in clearance system, a quick method for measurement of Strontium 90 was examined. In addition, the measuring methods for the judgment of the influence of fallout and for NR (Non-Radioactive) confirmation were examined. (author)

Clearance of materials from accelerator facilities

Directory of Open Access Journals (Sweden)

Rokni Sayed H.

2017-01-01

Full Text Available A new Technical Standard that supports the clearance of materials and equipment (personal property from U.S. Department of Energy (DOE accelerator facilities has been developed. The Standard focuses on personal property that has the potential to be radiologically impacted by accelerator operations. It addresses material clearance programs and protocols for off-site releases without restriction on use. Common metals with potential volumetric activation are of main interest with technical bases provided in Appendices of the Standard. The clearance protocols in the Standard include three elements: 1 clearance criteria, 2 process knowledge, and 3 measurement methods. This paper presents the technical aspects of the new Standard, discusses operational experience gained in clearance of materials and equipment from several accelerator facilities at SLAC and examples as to how this Standard can be applied to benefit the entirety of the DOE Accelerator Complex.

Clearance and release from control - An international perspective

International Nuclear Information System (INIS)

Thierfeldt, S.

2005-01-01

This paper tries to give an overview of the clearance, or release from regulatory control, on an international scale, including some of those countries where clearance has become or is about to become vital for D and D. The emphasis lies on the impact of clearance, and in particular of differences between clearance levels of various countries, on D and D. Relevance of clearance for D and D of nuclear installations Clearance is an essential part of waste management (or more general, material management) in nuclear installations, and in particular during the decommissioning phase where waste streams continues to arise. Of course, the relevance of clearance in a particular country depends on a number of factors, like: availability of a final repository and its price; prevailing decommissioning strategy; number of nuclear installations reaching decommissioning phase. This small selection of reasons why clearance may be of varying importance for different countries may already suffice to illustrate why up to now clearance has been developed and implemented in quite different ways. If one thinks of additional reasons that may influence clearance, like politics, the public opinion, availability of funds etc., the situation becomes even more complex. It is, however safe to draw the conclusion that countries with a certain number of nuclear installations which have been or will soon be shut down or which are already in the decommissioning phase will need to implement provisions for clearance. This has indeed been the case with countries like the UK, Germany, the USA, Sweden, and a number of others. It is not essential for clearance levels to be exactly equal between various countries. They may differ as long as the difference is not too large, e.g. the values fall into the same order of magnitude. This is the reason why for example Germany has no problems with clearance levels which differ from the EU recommendation RP 122 partially adopted in a number of EU countries

Improving Canada's Marine Navigation System through e-Navigation

Directory of Open Access Journals (Sweden)

Daniel Breton

2016-06-01

The conclusion proposed is that on-going work with key partners and stakeholders can be used as the primary mechanism to identify e-Navigation related innovation and needs, and to prioritize next steps. Moving forward in Canada, implementation of new e-navigation services will continue to be stakeholder driven, and used to drive improvements to Canada's marine navigation system.

Navigating on handheld displays: Dynamic versus Static Keyhole Navigation

NARCIS (Netherlands)

Mehra, S.; Werkhoven, P.; Worring, M.

2006-01-01

Handheld displays leave little space for the visualization and navigation of spatial layouts representing rich information spaces. The most common navigation method for handheld displays is static peephole navigation: The peephole is static and we move the spatial layout behind it (scrolling). A

Rational customs clearance technology choice

OpenAIRE

Shramenko, N.; Andriets, V.

2008-01-01

Issues concerning cargo delivery efficiencyincrease by choice of rational customs clearance technology have been considered. Three possible variants of customs clearance andmethods which allow to define the most rational version of cargo delivery in international road communication based on main efficiency criteria for definite distance have been presented.

7 CFR 1927.55 - Title clearance services.

Science.gov (United States)

2010-01-01

... REGULATIONS TITLE CLEARANCE AND LOAN CLOSING Real Estate Title Clearance and Loan Closing § 1927.55 Title clearance services. (a) Responsibilities of closing agents. Services to be provided to the agency and the borrower by a closing agent in connection with the transaction vary depending on whether a title insurance...

Relationship between silicon concentration and creatinine clearance

International Nuclear Information System (INIS)

Miura, Y.; Nakai, K.; Itoh, C.; Horikiri, J.; Sera, K.; Sato, M.

1998-01-01

Silicon levels in dialysis patients are markedly increasing. Using PIXE we determined the relationship between silicon concentration and creatinine clearance in 30 samples. Urine silicon concentration were significantly correlated to creatinine clearance (p<0.001). And also serum silicon concentration were significantly correlated to creatinine clearance (p<0.0001). (author)

Compressor airfoil tip clearance optimization system

Science.gov (United States)

Little, David A.; Pu, Zhengxiang

2015-08-18

A compressor airfoil tip clearance optimization system for reducing a gap between a tip of a compressor airfoil and a radially adjacent component of a turbine engine is disclosed. The turbine engine may include ID and OD flowpath boundaries configured to minimize compressor airfoil tip clearances during turbine engine operation in cooperation with one or more clearance reduction systems that are configured to move the rotor assembly axially to reduce tip clearance. The configurations of the ID and OD flowpath boundaries enhance the effectiveness of the axial movement of the rotor assembly, which includes movement of the ID flowpath boundary. During operation of the turbine engine, the rotor assembly may be moved axially to increase the efficiency of the turbine engine.

Noninvasive determination of individual renal clearance

International Nuclear Information System (INIS)

Chanard, J.; Brunois, J.P.; Ruiz, J.C.; Assailly, J.

1980-01-01

A noninvasive method for measurement of individual renal clearance is presented, based on analysis of the early rise of the kidneys' time-activity curves after injection of an appropriate tracer ( 131 I-ortho-iodohippurate for tubular function or 111 In DTPA for glomerular clearance). The analysis is based on the assumption that an insignificant amount of tracer leaves the kidney during the first few moments following injection. Therefore, the kidney activity during this period is directly proportional to the integral of the blood (heart) activity. After blood background subtraction, the linear correlation between the early part of the renogram and the corresponding blood integral activity curve allows calculation of an angular coefficient. The ratio of these coefficients calculated for each kidney is proportional to the ratio of the individual clearances. The latter are calculated from the total clearance simultaneously measured using a simplified method without urine collection. In control subjects with normal renal function individual renal clearances were not significantly different. In uninephrectomized patients a precision of 5% in calculating individual clearance was estimated from data recorded at the level of the remaining kidney. In patients with functional asymmetry, results were compared with 197 HgCl 2 quantitative renal fixation. A linear correlation was found (r = 0.95). The method we propose seems valuable for clinical investigation and allows sequential measurements. (orig.)

Theoretical Limits of Lunar Vision Aided Navigation with Inertial Navigation System

Science.gov (United States)

2015-03-26

THEORETICAL LIMITS OF LUNAR VISION AIDED NAVIGATION WITH INERTIAL NAVIGATION SYSTEM THESIS David W. Jones, Capt, USAF AFIT-ENG-MS-15-M-020 DEPARTMENT...Government and is not subject to copyright protection in the United States. AFIT-ENG-MS-15-M-020 THEORETICAL LIMITS OF LUNAR VISION AIDED NAVIGATION WITH...DISTRIBUTION UNLIMITED. AFIT-ENG-MS-15-M-020 THEORETICAL LIMITS OF LUNAR VISION AIDED NAVIGATION WITH INERTIAL NAVIGATION SYSTEM THESIS David W. Jones

A model of clearance rate regulation in mussels

Science.gov (United States)

Fréchette, Marcel

2012-10-01

Clearance rate regulation has been modelled as an instantaneous response to food availability, independent of the internal state of the animals. This view is incompatible with latent effects during ontogeny and phenotypic flexibility in clearance rate. Internal-state regulation of clearance rate is required to account for these patterns. Here I develop a model of internal-state based regulation of clearance rate. External factors such as suspended sediments are included in the model. To assess the relative merits of instantaneous regulation and internal-state regulation, I modelled blue mussel clearance rate and growth using a DEB model. In the usual standard feeding module, feeding is governed by a Holling's Type II response to food concentration. In the internal-state feeding module, gill ciliary activity and thus clearance rate are driven by internal reserve level. Factors such as suspended sediments were not included in the simulations. The two feeding modules were compared on the basis of their ability to capture the impact of latent effects, of environmental heterogeneity in food abundance and of physiological flexibility on clearance rate and individual growth. The Holling feeding module was unable to capture the effect of any of these sources of variability. In contrast, the internal-state feeding module did so without any modification or ad hoc calibration. Latent effects, however, appeared transient. With simple annual variability in temperature and food concentration, the relationship between clearance rate and food availability predicted by the internal-state feeding module was quite similar to that observed in Norwegian fjords. I conclude that in contrast with the usual Holling feeding module, internal-state regulation of clearance rate is consistent with well-documented growth and clearance rate patterns.

Predicting Human Clearance of OATP substrates using Cynomolgus monkey: In vitro-in vivo scaling of hepatic uptake clearance.

Science.gov (United States)

de Bruyn, Tom; Ufuk, Ayse; Cantrill, Carina; Kosa, Rachel E; Bi, Yi-An; Niosi, Mark; Modi, Sweta; Rodrigues, A David; Tremaine, Larry M; Varma, Manthena Vs; Galetin, Aleksandra; Houston, J Brian

2018-05-02

This work explores the utility of the cynomolgus monkey as a preclinical model to predict hepatic uptake clearance mediated by organic anion transporting polypeptide (OATP) transporters. Nine OATP substrates (rosuvastatin, pravastatin, repaglinide, fexofenadine, cerivastatin, telmisartan, pitavastatin, bosentan and valsartan) were investigated in plated cynomolgus monkey and human hepatocytes. Total uptake clearance and passive diffusion were measured in vitro from initial rates in the absence and presence of the OATP inhibitor rifamycin SV, respectively. Total uptake clearance values in plated hepatocytes ranged over three orders of magnitude in both species with a similar rank order and good agreement in the relative contribution of active transport to total uptake between cynomolgus monkey and human. In vivo hepatic clearance for these nine drugs was determined in cynomolgus monkey after intravenous dosing. Hepatic clearances showed a similar range to human parameters and good predictions from respective hepatocyte parameters (with 2.7 and 3.8-fold bias on average, respectively). The use of cross species empirical scaling factors (based on either dataset average or individual drug scaling factor from cynomolgus monkey data) improved prediction (less bias, better concordance) of human hepatic clearance from human hepatocyte data alone. In vitro intracellular binding in hepatocytes also correlated well between species. It is concluded that the minimal species differences observed for the current dataset between cynomolgus monkey and human hepatocyte uptake, both in vitro and in vivo, support future use of this preclinical model to delineate drug hepatic uptake and enable prediction of human in vivo intrinsic hepatic clearance. The American Society for Pharmacology and Experimental Therapeutics.

48 CFR 801.602-76 - Business clearance review.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Business clearance review... GENERAL DEPARTMENT OF VETERANS AFFAIRS ACQUISITION REGULATION SYSTEM Career Development, Contracting Authority, and Responsibilities 801.602-76 Business clearance review. (a) A business clearance review is a...

Estimation of 131I hippuran clearance during pregnancy

International Nuclear Information System (INIS)

Voigt, R.; Stoll, W.; Zenner, I.; Arndt, J.; Friedrich-Schiller-Univ., Jena

1979-01-01

Changes in 131 I hippuran clearance were estimated by a non-catheter method, as well as total clearance and clearance of each kidney, in 43 women at various stages of pregnancy and in 13 non-pregnant women who were not using hormonal contraceptives. The results are demonstrated in graph form. The methods used are described in detail. The procedure for determining clearance in separate kidneys is indicated. It was found that clearance values increased up to the 35th and 26th weeks of pregnancy. The difference between the sides that were found corresponds with the previously known difference in the function of the right and left kidneys and ureters. (orig.) [de

Establishing exemption and clearance criteria by the regulatory authority

International Nuclear Information System (INIS)

Salih, A.E.A.

2012-04-01

This Project work discusses the relationship between the concepts of exemption and clearance, and their practical use in the overall scheme of regulatory control of practices. It also discusses how exemptions and clearance is established and the scope of its applications for regulatory control. The concept of general clearance levels for any type of material and any possible pathway of disposal is also introduced in this work. Guidance of the Group of Experts establishing scenarios for general clearance, parameter values, and a nuclide-specific list of calculated clearance levels is also presented. Regulatory authorities are required to develop guidance on exemption and clearance levels to assist licensees and registrants to know which practices and sources within practices are exempted from regulatory control and those to be cleared from further controls. Exemption and clearance levels are tools for assisting the Regulatory Authority to optimize the use of resources. (author)

14 CFR 1260.63 - Customs clearance and visas.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Customs clearance and visas. 1260.63 Section 1260.63 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS General Special Conditions § 1260.63 Customs clearance and visas. Customs Clearance and Visas (For...

33 CFR 2.36 - Navigable waters of the United States, navigable waters, and territorial waters.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navigable waters of the United States, navigable waters, and territorial waters. 2.36 Section 2.36 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL JURISDICTION Jurisdictional Terms § 2.36 Navigable waters...

The influence of body posture on lithium clearance

DEFF Research Database (Denmark)

Kamper, A L; Strandgaard, S; Holstein-Rathlou, N H

1988-01-01

To establish appropriate standard circumstances for lithium clearance measurements, a study was undertaken in 12 healthy volunteers. In each subject, the glomerular filtration rate (GFR), as estimated by [51Cr]EDTA plasma clearance, and the renal clearances of lithium, sodium and potassium were...... during moderate physical activity. Hence, when renal tubular function is studied with the lithium clearance method, standardization of posture and physical activity is important. In such studies physical activity such as walking should particularly be avoided....... measured four times at 1-week intervals: two in the supine and one in the sitting position, and one when the subject was walking around. Glomerular filtration rate was not influenced by posture changes. On the contrary, lithium clearance, which in the supine position was 30 +/- 9 ml/min (1 SD), tended...

The influence of body posture on lithium clearance

DEFF Research Database (Denmark)

Kamper, A L; Strandgaard, S; Holstein-Rathlou, N H

1988-01-01

To establish appropriate standard circumstances for lithium clearance measurements, a study was undertaken in 12 healthy volunteers. In each subject, the glomerular filtration rate (GFR), as estimated by [51Cr]EDTA plasma clearance, and the renal clearances of lithium, sodium and potassium were...... measured four times at 1-week intervals: two in the supine and one in the sitting position, and one when the subject was walking around. Glomerular filtration rate was not influenced by posture changes. On the contrary, lithium clearance, which in the supine position was 30 +/- 9 ml/min (1 SD), tended...... during moderate physical activity. Hence, when renal tubular function is studied with the lithium clearance method, standardization of posture and physical activity is important. In such studies physical activity such as walking should particularly be avoided....

Clearance Laboratory - Capability and measurement sensitivity

Energy Technology Data Exchange (ETDEWEB)

Hedemann Jensen, P.; Lauridsen, B.; Silva, J.; Soegaard-Hansen, J.; Warming, L.

2005-08-01

A new low-level Clearance Laboratory has been built at the Risoe-site. Building materials with a low content of naturally occurring radionuclides have been used. To minimize transport of radon gas from soil into the laboratory the foundation has been supplied with a membrane. The laboratory has been equipped with two high-efficiency germanium detectors. These detectors will be used for clearance measurements on the predicted amount of 15,000 - 18,000 tonnes of non-active or nearly non-active materials, which will originate from the decommissioning of all the nuclear facilities at the Risoe-site. They will be used also for clearance measurements on buildings and land. Objects and materials to be measured for clearance are placed on a rotation table that can carry up to one tonne and can rotate once a minute to simulate some averaging of inhomogeneously distributed activity. Sensitivity and background measurements reveal that measuring times of 20 - 50 minutes would normally be sufficient to detect radionuclide concentrations of only a small fraction of the nuclide-specific clearance levels with a sufficiently low uncertainty. Probability calculations of the measurement capacity of the Clearance Laboratory indicate that the mean value of the total measuring time for all materials that potentially can be cleared would be 13 years with a 95% probability of being less than 25 years. The mean value of the annual amount of materials that can be measured in the laboratory is 600 tonnes with a 95% probability of being less than 1,200 tonnes. If needed, there is room for additional measuring systems to increase the capacity of the laboratory. (au)

Clearance Laboratory - Capability and measurement sensitivity

International Nuclear Information System (INIS)

Hedemann Jensen, P.; Lauridsen, B.; Silva, J.; Soegaard-Hansen, J.; Warming, L.

2005-09-01

A new low-level Clearance Laboratory has been built at the Risoe-site. Building materials with a low content of naturally occurring radionuclides have been used. To minimize transport of radon gas from soil into the laboratory the foundation has been supplied with a membrane. The laboratory has been equipped with two high-efficiency germanium detectors. These detectors will be used for clearance measurements on the predicted amount of 15,000 - 18,000 tonnes of non-active or nearly non-active materials, which will originate from the decommissioning of all the nuclear facilities at the Risoe-site. They will be used also for clearance measurements on buildings and land. Objects and materials to be measured for clearance are placed on a rotation table that can carry up to one tonne and can rotate once a minute to simulate some averaging of inhomogeneously distributed activity. Sensitivity and background measurements reveal that measuring times of 20 - 50 minutes would normally be sufficient to detect radionuclide concentrations of only a small fraction of the nuclide-specific clearance levels with a sufficiently low uncertainty. Probability calculations of the measurement capacity of the Clearance Laboratory indicate that the mean value of the total measuring time for all materials that potentially can be cleared would be 13 years with a 95% probability of being less than 25 years. The mean value of the annual amount of materials that can be measured in the laboratory is 600 tonnes with a 95% probability of being less than 1,200 tonnes. If needed, there is room for additional measuring systems to increase the capacity of the laboratory. (au)

77 FR 42637 - Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments; Corrections

Science.gov (United States)

2012-07-20

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Parts 84 and 115 [Docket No. USCG-2012-0306] RIN 1625-AB86 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments...), the Coast Guard published a final rule entitled ``Navigation and Navigable Waters; Technical...

Lithium clearance in chronic nephropathy

DEFF Research Database (Denmark)

Kamper, A L; Holstein-Rathlou, N H; Leyssac, P P

1989-01-01

1. Lithium clearance measurements were made in 72 patients with chronic nephropathy of different aetiology and moderate to severely reduced renal function. 2. Lithium clearance was strictly correlated with glomerular filtration rate, and there was no suggestion of distal tubular reabsorption...... of lithium or influence of osmotic diuresis. 3. Fractional reabsorption of lithium was reduced in most patients with glomerular filtration rates below 25 ml/min. 4. Calculated fractional distal reabsorption of sodium was reduced in most patients with glomerular filtration rates below 50 ml/min. 5. Lithium...... that lithium clearance may be a measure of the delivery of sodium and water from the renal proximal tubule. With this assumption it was found that adjustment of the sodium excretion in chronic nephropathy initially takes place in the distal parts of the nephron (loop of Henle, distal tubule and collecting duct...

Experience and lessons learnt from clearance in Germany

International Nuclear Information System (INIS)

Thierfeldt, Stefan

2002-01-01

Clearance is an important corner-stone of waste management in nuclear installations in Germany. It has been practised successfully for around two decades. The importance of clearance can also be judged from the fact that it has been included detailedly in the new German Radiation Protection Ordinance. Currently, there are 19 NPPs and a number of fuel cycle installations in operation in Germany. The main waste quantities, however, arise from the dismantling of NPPs and fuel cycle installations which are currently in decommissioning. As most of the decommissioning projects are targeted for early dismantling instead of safe enclosure, there is already considerable experience with the application of clearance procedures and verification of clearance levels. The German waste management strategy is governed by two options: Clearance of the material (after decontamination and release measurement). After clearance, the material is no longer regarded as radioactive in a legal sense. Final disposal of the material as radioactive waste in a deep geological repository (no near-surface disposal facilities exist or are planned in Germany). A deep geological repository is planned to be operable around 2030. Stefan Thierfeldt described German clearance requirements and lessons learned from their application to decommissioning of power reactors. The great majority of the waste was in fact recycled, although the costs were dominated by the small fraction that had to be disposed of as radioactive waste. Among the lessons learned from the German experience were some revealing insights into the public perception of both clearance and of recycling of material from decommissioning of a nuclear installation

19 CFR 122.26 - Entry and clearance.

Science.gov (United States)

2010-04-01

... AIR COMMERCE REGULATIONS Private Aircraft § 122.26 Entry and clearance. Private aircraft, as defined... information as set forth in § 122.22(c), and grants electronic clearance via electronic mail or telephone...

Comparison of renal clearance of 99mTc-DTPA and inulin, 131I-hippurate and PAH as well as of the creatinine clearance in Wistar rats

International Nuclear Information System (INIS)

Hagemann, J.; Li Min Su; Strangfeld, D.; Schuerer, M.; Siewert, H.; Pietsch, R.; Kruse, I.; Priem, F.

1988-01-01

Order of magnitude and standard deviation of 99m Tc-DTPA and 131 I-hippurate slope clearance were analyzed successively in 56 male Wistar rats. The clearance of 99m Tc-DTPA was 17.4 ± 3.43 μl · s -1 (100 g b-w) -1 , of 131 I-hippurate 34.3 ± 7.21 μl · s -1 (100 g b-w) -1 . In 17 rats inulin and PAH clearances were analyzed by steady state method with permanent infusion and 3 to 4 urine collection periods 3 days later. The endogeneous creatinine clearance was determined within the same periods. The 99m Tc-DTPA slope clearance corresponded to the inulin clearance, as well as the hippurate clearance to the PAH clearance. The high filtration fraction calculated from nuclear medicine and chemical clearance methods and the low PAH extraction (42%) let suggest that PAH and hippurate are eliminated only incompletely from plasma in rat kidney and are unsuitable for determination of renal blood supply in rats. The creatinine clearance with 4.7 ± 1.38 μl · s -1 (100 g b-w) -1 was far beneath the clearance of inulin and 99m Tc-DTPA, supposing that creatinine is reabsorbed tubularly in part and the creatinine clearance can not be used for valuation of the GFR in rats. However, for this the 99m Tc-DTPA clearance in Wistar rats seems to be well suited. (author)

Clearance systems in the brain—implications for Alzheimer disease

Science.gov (United States)

Tarasoff-Conway, Jenna M.; Carare, Roxana O.; Osorio, Ricardo S.; Glodzik, Lidia; Butler, Tracy; Fieremans, Els; Axel, Leon; Rusinek, Henry; Nicholson, Charles; Zlokovic, Berislav V.; Frangione, Blas; Blennow, Kaj; Ménard, Joël; Zetterberg, Henrik; Wisniewski, Thomas; de Leon, Mony J.

2015-01-01

Accumulation of toxic protein aggregates—amyloid-β (Aβ) plaques and hyperphosphorylated tau tangles—is the pathological hallmark of Alzheimer disease (AD). Aβ accumulation has been hypothesized to result from an imbalance between Aβ production and clearance; indeed, Aβ clearance seems to be impaired in both early and late forms of AD. To develop efficient strategies to slow down or halt AD, it is critical to understand how Aβ is cleared from the brain. Extracellular Aβ deposits can be removed from the brain by various clearance systems, most importantly, transport across the blood–brain barrier. Findings from the past few years suggest that astroglial-mediated interstitial fluid (ISF) bulk flow, known as the glymphatic system, might contribute to a larger portion of extracellular Aβ (eAβ) clearance than previously thought. The meningeal lymphatic vessels, discovered in 2015, might provide another clearance route. Because these clearance systems act together to drive eAβ from the brain, any alteration to their function could contribute to AD. An understanding of Aβ clearance might provide strategies to reduce excess Aβ deposits and delay, or even prevent, disease onset. In this Review, we describe the clearance systems of the brain as they relate to proteins implicated in AD pathology, with the main focus on Aβ. PMID:26195256

Clearance systems in the brain-implications for Alzheimer disease.

Science.gov (United States)

Tarasoff-Conway, Jenna M; Carare, Roxana O; Osorio, Ricardo S; Glodzik, Lidia; Butler, Tracy; Fieremans, Els; Axel, Leon; Rusinek, Henry; Nicholson, Charles; Zlokovic, Berislav V; Frangione, Blas; Blennow, Kaj; Ménard, Joël; Zetterberg, Henrik; Wisniewski, Thomas; de Leon, Mony J

2015-08-01

Accumulation of toxic protein aggregates-amyloid-β (Aβ) plaques and hyperphosphorylated tau tangles-is the pathological hallmark of Alzheimer disease (AD). Aβ accumulation has been hypothesized to result from an imbalance between Aβ production and clearance; indeed, Aβ clearance seems to be impaired in both early and late forms of AD. To develop efficient strategies to slow down or halt AD, it is critical to understand how Aβ is cleared from the brain. Extracellular Aβ deposits can be removed from the brain by various clearance systems, most importantly, transport across the blood-brain barrier. Findings from the past few years suggest that astroglial-mediated interstitial fluid (ISF) bulk flow, known as the glymphatic system, might contribute to a larger portion of extracellular Aβ (eAβ) clearance than previously thought. The meningeal lymphatic vessels, discovered in 2015, might provide another clearance route. Because these clearance systems act together to drive eAβ from the brain, any alteration to their function could contribute to AD. An understanding of Aβ clearance might provide strategies to reduce excess Aβ deposits and delay, or even prevent, disease onset. In this Review, we describe the clearance systems of the brain as they relate to proteins implicated in AD pathology, with the main focus on Aβ.

Secretin enhances [14C]erythritol clearance in unanesthetized dogs

International Nuclear Information System (INIS)

Lewis, M.H.; Baker, A.L.; Dhorajiwala, J.; Moossa, A.R.

1982-01-01

To determine the effect of secretin infusion on clearance of inert markers into bile, unanesthetized dogs fitted with Thomas cannulas received continuous infusions of [ 14 C]erythritol and [ 3 H]inulin throughout study. Taurocholic acid administered sequentially at 9.0, 20.0, and 40.0 mumol/min enhanced [ 14 C]erythritol clearance, and GIH secretin (3 units/min) administered along with TCA (40.0 mumol/min) increased [ 14 C]erythritol clearance from 4.9 +/- 1.2 ml/10 min to 6.8 +/- 1.3 ml/10 min (P less than 0.001), but simultaneously measured [ 3 H]inulin clearance was unaltered. Secretin alone also increased [ 14 C]erythritol clearance but did not alter [ 3 H]inulin clearance. The increase in [ 14 C]erythritol clearance per unit increase in bile flow was less during secretin infusion than TCA. Thus, secretin increases [ 14 C]erythritol transport through restricted channels, probably distal to the canaliculi. [ 14 C]Erythritol may not be an accurate marker for canalicular bile flow in dogs during secretin infusion

Radar and electronic navigation

CERN Document Server

Sonnenberg, G J

2013-01-01

Radar and Electronic Navigation, Sixth Edition discusses radar in marine navigation, underwater navigational aids, direction finding, the Decca navigator system, and the Omega system. The book also describes the Loran system for position fixing, the navy navigation satellite system, and the global positioning system (GPS). It reviews the principles, operation, presentations, specifications, and uses of radar. It also describes GPS, a real time position-fixing system in three dimensions (longitude, latitude, altitude), plus velocity information with Universal Time Coordinated (UTC). It is accur

Comparison of renal clearance of 99mTc-DTPA and inulin 131I-hippurate and PAH as well as creatinine clearance in Wistar-rats

International Nuclear Information System (INIS)

Hagemann, J.; Li Min Su; Strangfeld, D.; Schuerer, M.; Siewert, H.; Pietsch, R.; Kruse, I.; Priem, F.

1988-01-01

Averages and standard deviations of 99m Tc-DTPA and 131 I-hippurate slope clearance were consecutively determined for 56 male Wistar rats, with a body-weight of 271 ± 69 g in a single investigation. Clearance of 99m Tc-DTPA was 17.4 ± 3.4, that of 131 I-hippurate was 34.3 ± 7.2 μl · s -1 per 100 g body weight. For 17 rats inulin and PAH clearances were determined after 3 days with the steady-state method with continuous infusion and 3-4 periods of urine collection. During the same periods endogeneous creatinine clearance was determined. 99m Tc-DTPA slope clearance correlated well with inulin clearance, also the hippurate with the PAH clearance. The high values of the filtration fraction, calculated from radioisotope and chemical methods, and the low PAH extraction of 42% lead to the conclusion, that PAH and hippurate are incompletely eliminated by the rat kidney from plasma and therefore are inadequate for determining renal blood flow in rats. Creatinine clearance was 4.7 ± 1.38 μl · s -1 per 100 g body weight, much lower than that of inulin and 99m Tc-DTPA. Therefore is assumed, that tubular reabsorption of creatinine occurs and creatinine clearance cannot serve for the evaluation of GFR in rats. For this, however, the clearance of 99m Tc-DTPA seems well applicable in Wistar rats. (author)

Metabolic clearance rate and urinary clearance of purified beta-core

International Nuclear Information System (INIS)

Wehmann, R.E.; Blithe, D.L.; Flack, M.R.; Nisula, B.C.

1989-01-01

We injected a highly purified preparation of the beta-core molecule, a fragment of hCG beta excreted in pregnancy urine, into five men and three women to determine its kinetic parameters, MCR, and urinary clearance. The beta-core molecule was distributed in an initial volume [1950 +/- 156 (mean +/- SEM) mL/m2 body surface area] approximately equal to the estimated plasma volume. Its disappearance was multiexponential on a semilogarithmic plot, with a rapid phase t1/2 of 3.5 +/- 0.7 min and a slow phase t1/2 of 22.4 +/- 4.2 min. The transit time (the mean time spent by a molecule of beta-core in transit) was 20.6 +/- 2.1 min. The MCR was 192.0 +/- 8.0 mL/min.m2 body surface area. About 5% of the injected dose of beta-core was excreted into the urine in the first 30 min after injection, and low levels of excretion persisted for up to 7 days. The urinary clearance rate of beta-core was 13.7 +/- 1.4 mL/min.m2, accounting for about 8% of the elimination of beta-core from the plasma. The beta-core immunoreactivity in serum and urine was characterized by gel filtration and three independent RIA systems to show that its properties were indistinguishable from those of the injected beta-core. Serum levels of beta-core in pregnant women were less than 0.2 ng/mL, while the amounts excreted in their urine were as much as 5 mg/day. Based on these clearance parameters of beta-core in normal subjects, less than 0.2% of the beta-core excreted in pregnancy urine is derived by urinary clearance of plasma beta-core. Therefore, more than 99% of the beta-core excreted in pregnancy urine is derived from beta-core in a compartment separate from plasma. In particular, these data indicate that there is relatively little placental secretion of beta-core into plasma and that placental secretion does not account for the vast majority of beta-core in pregnancy urine

Allometric scaling for predicting human clearance of bisphenol A

International Nuclear Information System (INIS)

Collet, Séverine H.; Picard-Hagen, Nicole; Lacroix, Marlène Z.; Puel, Sylvie; Viguié, Catherine; Bousquet-Melou, Alain; Toutain, Pierre-Louis; Gayrard, Véronique

2015-01-01

The investigation of interspecies differences in bisphenol A (BPA) pharmacokinetics (PK) may be useful for translating findings from animal studies to humans, identifying major processes involved in BPA clearance mechanisms, and predicting BPA PK parameters in man. For the first time, a large range of species in terms of body weight, from 0.02 kg (mice) to 495 kg (horses) was used to predict BPA clearance in man by an allometric approach. BPA PK was evaluated after intravenous administration of BPA in horses, sheep, pigs, dogs, rats and mice. A non-compartmental analysis was used to estimate plasma clearance and steady state volume of distribution and predict BPA PK parameters in humans from allometric scaling. In all the species investigated, BPA plasma clearance was high and of the same order of magnitude as their respective hepatic blood flow. By an allometric scaling, the human clearance was estimated to be 1.79 L/min (equivalent to 25.6 mL/kg.min) with a 95% prediction interval of 0.36 to 8.83 L/min. Our results support the hypothesis that there are highly efficient and hepatic mechanisms of BPA clearance in man. - Highlights: • Allometric scaling was used to predict BPA pharmacokinetic parameters in humans. • In all species, BPA plasma clearance approached hepatic blood flow. • Human BPA clearance was estimated to be 1.79 L/min

Allometric scaling for predicting human clearance of bisphenol A

Energy Technology Data Exchange (ETDEWEB)

Collet, Séverine H., E-mail: s.collet@envt.fr; Picard-Hagen, Nicole, E-mail: n.hagen-picard@envt.fr; Lacroix, Marlène Z., E-mail: m.lacroix@envt.fr; Puel, Sylvie, E-mail: s.puel@envt.fr; Viguié, Catherine, E-mail: c.viguie@envt.fr; Bousquet-Melou, Alain, E-mail: a.bousquet-Melou@envt.fr; Toutain, Pierre-Louis, E-mail: pltoutain@wanadoo.fr; Gayrard, Véronique, E-mail: v.gayrard@envt.fr

2015-05-01

The investigation of interspecies differences in bisphenol A (BPA) pharmacokinetics (PK) may be useful for translating findings from animal studies to humans, identifying major processes involved in BPA clearance mechanisms, and predicting BPA PK parameters in man. For the first time, a large range of species in terms of body weight, from 0.02 kg (mice) to 495 kg (horses) was used to predict BPA clearance in man by an allometric approach. BPA PK was evaluated after intravenous administration of BPA in horses, sheep, pigs, dogs, rats and mice. A non-compartmental analysis was used to estimate plasma clearance and steady state volume of distribution and predict BPA PK parameters in humans from allometric scaling. In all the species investigated, BPA plasma clearance was high and of the same order of magnitude as their respective hepatic blood flow. By an allometric scaling, the human clearance was estimated to be 1.79 L/min (equivalent to 25.6 mL/kg.min) with a 95% prediction interval of 0.36 to 8.83 L/min. Our results support the hypothesis that there are highly efficient and hepatic mechanisms of BPA clearance in man. - Highlights: • Allometric scaling was used to predict BPA pharmacokinetic parameters in humans. • In all species, BPA plasma clearance approached hepatic blood flow. • Human BPA clearance was estimated to be 1.79 L/min.

Locomotor circumvention strategies are altered by stroke: I. Obstacle clearance.

Science.gov (United States)

Darekar, Anuja; Lamontagne, Anouk; Fung, Joyce

2017-06-15

Functional locomotion requires the ability to adapt to environmental challenges such as the presence of stationary or moving obstacles. Difficulties in obstacle circumvention often lead to restricted community ambulation in individuals with stroke. The objective of this study was to contrast obstacle circumvention strategies between post-stroke (n = 12) and healthy individuals (n = 12) performing locomotor and perceptuomotor (joystick navigation) tasks with different obstacle approaches. Participants walked and navigated with a joystick towards a central target, in a virtual environment simulating a large room, while avoiding an obstacle that either remained stationary at the pre-determined point of intersection or moved from head-on or diagonally 30° left/right. The outcome measures included dynamic clearance (DC), instantaneous distance from obstacle at crossing (IDC), number of collisions and preferred side of circumvention. These measures were compared between groups (stroke vs. healthy), obstacle parameter (stationary vs. moving head-on) and direction of approach (left/paretic vs. right/non-paretic). DC was significantly larger when circumventing a moving obstacle that approached head-on as compared to a stationary obstacle for both groups during both tasks, while not significantly different in either diagonal approach in either group. IDC was smaller in the stroke group while walking and larger in both groups during joystick navigation when avoiding moving as compared to stationary obstacle. IDC was significantly larger in the stroke group compared to controls for diagonal approaches during walking, wherein two different strategies emerged amongst individuals with stroke: circumventing to the same (V same n = 6) or opposite (V opp n = 4) side of obstacle approach. This behavior was not seen in the perceptuomotor task, wherein post-stroke participants circumvented to opposite side of the obstacle approach as seen in healthy participants. In the

48 CFR 2452.237-75 - Clearance of contractor personnel.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Clearance of contractor... Clauses 2452.237-75 Clearance of contractor personnel. As prescribed in 2437.110(e), insert the following clause in solicitations and contracts. Clearance of Contractor Personnel (OCT 1999) (a) General. This...

Hydrographic and navigational analysis of Lower Oder shipping conditions – case study of the backflow occurrence

Directory of Open Access Journals (Sweden)

Medyna Piotr

2017-01-01

Full Text Available One of the significant limitations of inland waterway transport on the Oder River is the water level. Its variability determines the minimum clearance under the bridges and thus the maximum drought of moving vessels. An important factor affecting the water level in the Oder River is the phenomenon of wind backwater. Certain pressure field distribution situations may affect in an increase of water level on the coast and thereby block the outflow of river waters. In this paper an example of the limitations of inland navigation in the estuarine part of the Lower Oder under the weather conditions on the southern Baltic Sea in autumn 2016 is presented. For the analysis area of Szczecin Waterway Node and section of Oder River from Szczecin to Gryfino was chosen. Based on data the weather and navigational conditions of the area of the Lower Oder were assessed. Occurring winds, currents and changes in water level has been analyzed. In the situations of unfavorable raise of the water level in the river, inland navigation is redirected to the section of Regalica River, and a section of the port of Szczecin region is closed. This causes obvious difficulties and results in prolonged ships routes. Additional obstacle that take place here is an arbitrarily determined time of railway bridge span lifting in Szczecin Podjuchy.

Comparative evaluation of iohexol and inulin clearance for glomerular filtration rate determinations

International Nuclear Information System (INIS)

Lindblad, H.G.; Berg, U.B.

1994-01-01

The authors have evaluated iohexol as a filtration marker in 150 children. The clearance of iohexol was compared with that of inulin or with a formula clearance. The single-sample clearance of iohexol showed a good correlation with the clearance of inulin. The clearance of iohexol correlated well with the formula clearance. The optimal blood sampling time for iohexol clearance determinations appears to be between 120 and 180 min after injection, at least in patient with relatively normal filtration rates. It is concluded that iohexol clearance is an accurate method of determining the glomerular filtration rate in clinical practice. 25 refs., 5 figs

Security Clearance Tracking System

Data.gov (United States)

National Archives and Records Administration — SCTS supports the adjudication process of private background investigations and clearances for potential employees, contractors, interns and student workers.

Centrifugal compressor tip clearance and impeller flow

Energy Technology Data Exchange (ETDEWEB)

Jaatinen-Varri, Ahti; Tiainen, Jonna; Turunen-Saaresti, Teemu; Gronman, Aki; Ameli, Alireza; Backman, Jari [Laboratory of Fluid Dynamics, LUT School of Energy Systems, Lappeenranta University of Technology, Lappeenranta (Finland); Engeda, Abraham [Turbomachinery Laboratory, Dept. of Mechanical Engineering, Michigan State University, East Lansing (United States)

2016-11-15

Compressors consume a considerable portion of the electricity used in the industrial sector. Hence, improvements in compressor efficiency lead to energy savings and reduce environmental impacts. The efficiency of an unshrouded centrifugal compressor suffers from leakage flow over the blade tips. The effect of tip leakage flow on the passage flow differs between the full and splitter blade passages. In this study, the differences in the flow fields between the full and splitter blade passages were studied numerically in detail. An industrial high-speed compressor with a design pressure ratio of 1.78 was modelled. Numerical studies were conducted with six different tip clearances and three different diffuser widths. The results show that increasing tip clearance considerably increases the reversed flow into the impeller with an unpinched diffuser. The reversed flow then partly mixes into the flow in the same blade passage it entered the impeller and the rest migrates over the blade, mixing with the tip clearance flow. Furthermore, as the reversed and clearance flow mix into the wake, the wake is weakened. As pinch reduces both the reversed flow and clearance flow, the passage wakes are stronger with pinches. However, the pinch is beneficial as the losses at the impeller outlet decrease.

Centrifugal compressor tip clearance and impeller flow

International Nuclear Information System (INIS)

Jaatinen-Varri, Ahti; Tiainen, Jonna; Turunen-Saaresti, Teemu; Gronman, Aki; Ameli, Alireza; Backman, Jari; Engeda, Abraham

2016-01-01

Compressors consume a considerable portion of the electricity used in the industrial sector. Hence, improvements in compressor efficiency lead to energy savings and reduce environmental impacts. The efficiency of an unshrouded centrifugal compressor suffers from leakage flow over the blade tips. The effect of tip leakage flow on the passage flow differs between the full and splitter blade passages. In this study, the differences in the flow fields between the full and splitter blade passages were studied numerically in detail. An industrial high-speed compressor with a design pressure ratio of 1.78 was modelled. Numerical studies were conducted with six different tip clearances and three different diffuser widths. The results show that increasing tip clearance considerably increases the reversed flow into the impeller with an unpinched diffuser. The reversed flow then partly mixes into the flow in the same blade passage it entered the impeller and the rest migrates over the blade, mixing with the tip clearance flow. Furthermore, as the reversed and clearance flow mix into the wake, the wake is weakened. As pinch reduces both the reversed flow and clearance flow, the passage wakes are stronger with pinches. However, the pinch is beneficial as the losses at the impeller outlet decrease

33 CFR 66.05-100 - Designation of navigable waters as State waters for private aids to navigation.

Science.gov (United States)

2010-07-01

... as State waters for private aids to navigation. 66.05-100 Section 66.05-100 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-100 Designation of navigable waters as State waters for private aids to...

Hepatic drug clearance following traumatic injury.

Science.gov (United States)

Slaughter, R L; Hassett, J M

1985-11-01

Trauma is a complex disease state associated with physiologic changes that have the potential to alter hepatic drug clearance mechanisms. These responses include alterations in hepatic blood flow, reduction in hepatic microsomal activity, reduction in hepatic excretion processes, and changes in protein binding. Hepatic blood flow is influenced by sympathomimetic activity. Both animal and human studies demonstrate an initial reduction and subsequent increase in hepatic blood flow, which coincides with an observed increase and subsequent return to normal in serum catecholamine concentrations. Unfortunately, there are no human studies that address the importance these findings may have to the clearance processes of high intrinsic clearance compounds. Animal studies of trauma indicate that hepatic microsomal activity is depressed during the post-traumatic period. Reduction in the hepatic clearance of antipyrine, a model low intrinsic compound, has also been demonstrated in animal models of trauma. In addition to these effects, hepatic excretion of substances such as indocyanine green and bilirubin have been demonstrated to be impaired in both traumatized animals and humans. Finally, substantial increases in the serum concentration of the binding protein alpha 1-acid glycoprotein occur in trauma patients. This has been reported to be associated with subsequent decreases in the free fraction of lidocaine and quinidine. In addition to changing serum drug concentration/response relationships, the pharmacokinetic behavior of drugs bound to alpha 1-acid glycoprotein should also change. Preliminary observations in our laboratory in a dog model of surgically-induced trauma have shown a reduction in the total clearance of lidocaine and reduction in free lidocaine concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Diminished creatinine clearance in anorexia nervosa: reversal with weight gain.

OpenAIRE

Boag, F; Weerakoon, J; Ginsburg, J; Havard, C W; Dandona, P

1985-01-01

To assess whether patients with anorexia nervosa have abnormalities in creatinine clearance, we measured plasma creatinine concentration, urinary creatinine excretion, and creatinine clearance in 10 patients with anorexia nervosa before and during treatment. Urinary creatinine excretion and creatinine clearance were diminished in all patients. Nine patients had significant decreases in their plasma creatinine and creatinine clearance was increased even when corrected for body weight and body ...

Cerebrospinal Fluid Clearance in Alzheimer Disease Measured with Dynamic PET.

Science.gov (United States)

de Leon, Mony J; Li, Yi; Okamura, Nobuyuki; Tsui, Wai H; Saint-Louis, Les A; Glodzik, Lidia; Osorio, Ricardo S; Fortea, Juan; Butler, Tracy; Pirraglia, Elizabeth; Fossati, Silvia; Kim, Hee-Jin; Carare, Roxana O; Nedergaard, Maiken; Benveniste, Helene; Rusinek, Henry

2017-09-01

Evidence supporting the hypothesis that reduced cerebrospinal fluid (CSF) clearance is involved in the pathophysiology of Alzheimer disease (AD) comes primarily from rodent models. However, unlike rodents, in which predominant extracranial CSF egress is via olfactory nerves traversing the cribriform plate, human CSF clearance pathways are not well characterized. Dynamic PET with 18 F-THK5117, a tracer for tau pathology, was used to estimate the ventricular CSF time-activity as a biomarker for CSF clearance. We tested 3 hypotheses: extracranial CSF is detected at the superior turbinates; CSF clearance is reduced in AD; and CSF clearance is inversely associated with amyloid deposition. Methods: Fifteen subjects, 8 with AD and 7 normal control volunteers, were examined with 18 F-THK5117. Ten subjects additionally underwent 11 C-Pittsburgh compound B ( 11 C-PiB) PET scanning, and 8 were 11 C-PiB-positive. Ventricular time-activity curves of 18 F-THK5117 were used to identify highly correlated time-activity curves from extracranial voxels. Results: For all subjects, the greatest density of CSF-positive extracranial voxels was in the nasal turbinates. Tracer concentration analyses validated the superior nasal turbinate CSF signal intensity. AD patients showed ventricular tracer clearance reduced by 23% and 66% fewer superior turbinate CSF egress sites. Ventricular CSF clearance was inversely associated with amyloid deposition. Conclusion: The human nasal turbinate is part of the CSF clearance system. Lateral ventricle and superior nasal turbinate CSF clearance abnormalities are found in AD. Ventricular CSF clearance reductions are associated with increased brain amyloid depositions. These data suggest that PET-measured CSF clearance is a biomarker of potential interest in AD and other neurodegenerative diseases. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

Analysis of conservativity analysis for clearance levels. Final report

International Nuclear Information System (INIS)

Deckert, A.; Thierfeldt, S.

1997-07-01

When deriving clearance levels for material from nuclear installations it is necessary to proceed with a certain degree of conservativity. This can, however, differ between various sets of clearance levels leading to inconsistencies between clearance pathways. The aim of the work therefore is to compare levels of conservativity for the following two sets of clearance levels: clearance levels for disposal as conventional waste and for metallic materials for recycling/reuse. A method was developed to quantify the degree of conservativity and make it comparable. The actual and future situation for disposal of (conventional) wastes in Germany was analysed. In addition, the masses, nuclide vectors, geographical distribution etc. for slightly radioactive material being cleared for conventional disposal was analysed and modelled and the resulting dose distributions were calculated. The values for the clearance levels were taken from the 1995 recommendation by the German Commission on Radiation Protection (SSK). By using realistic scenarios, the exposure was calculated for the personnel on the landfills and for persons of the general public being exposed via groundwater pathways. It could be shown that the trivial dose range will not be exceeded even if the masses of cleared material per landfill site exceed 100 Mg/a. Because of the types and distribution of nuclear installations in Germany and because of the nuclide vectors it is therefore not necessary to limit the masses per landfill sites. Clearance levels that are determined by the exposure pathways external exposure to and the inhalation of dust by the landfill personnel show a similar level of conservativity as those for metal scrap. This means that the clearance levels for gamma emitting nuclides are not overly restrictive. Although radiologically justified, raising the clearance levels would not lead to an increase of the material quantities because other nuclides of the respective nuclide vectors are limiting. In

Navigation Problems in Blind-to-Blind Pedestrians Tele-assistance Navigation

OpenAIRE

Balata , Jan; Mikovec , Zdenek; Maly , Ivo

2015-01-01

International audience; We raise a question whether it is possible to build a large-scale navigation system for blind pedestrians where a blind person navigates another blind person remotely by mobile phone. We have conducted an experiment, in which we observed blind people navigating each other in a city center in 19 sessions. We focused on problems in the navigator’s attempts to direct the traveler to the destination. We observed 96 problems in total, classified them on the basis of the typ...

Numerical investigation of hub clearance flow in a Kaplan turbine

Science.gov (United States)

Wu, H.; Feng, J. J.; Wu, G. K.; Luo, X. Q.

2012-11-01

In this paper, the flow field considering the hub clearance flow in a Kaplan turbine has been investigated through using the commercial CFD code ANSYS CFX based on high-quality structured grids generated by ANSYS ICEM CFD. The turbulence is simulated by k-ω based shear stress transport (SST) turbulence model together with automatic near wall treatments. Four kinds of simulations have been conducted for the runner geometry without hub clearance, with only the hub front clearance, with only the rear hub clearance, and with both front and rear clearance. The analysis of the obtained results is focused on the flow structure of the hub clearance flow, the effect on the turbine performance including hydraulic efficiency and cavitation performance, which can improve the understanding on the flow field in a Kaplan turbine.

Numerical investigation of hub clearance flow in a Kaplan turbine

International Nuclear Information System (INIS)

Wu, H; Feng, J J; Wu, G K; Luo, X Q

2012-01-01

In this paper, the flow field considering the hub clearance flow in a Kaplan turbine has been investigated through using the commercial CFD code ANSYS CFX based on high-quality structured grids generated by ANSYS ICEM CFD. The turbulence is simulated by k-ω based shear stress transport (SST) turbulence model together with automatic near wall treatments. Four kinds of simulations have been conducted for the runner geometry without hub clearance, with only the hub front clearance, with only the rear hub clearance, and with both front and rear clearance. The analysis of the obtained results is focused on the flow structure of the hub clearance flow, the effect on the turbine performance including hydraulic efficiency and cavitation performance, which can improve the understanding on the flow field in a Kaplan turbine.

Determination of renal clearance of 131I-hippuran

International Nuclear Information System (INIS)

Ridzon, S.

1982-01-01

The author presents his own method for the determination of total renal clearance of 131 I-hippuran under conditions of its diminishing plasma concentration following single intravenous administration. Total renal clearance is determined as the ratio of the amount of activity excreted into the urine over a certain time interval and of the area limited by the curve of activity decrease in plasma and by the time axis in the corresponding interval. The results are demonstrated in five investigated healthy subjects, and very good agreement of the calculated values of total renal clearance for different time intervals in the same subject is pointed out. When isotope nephrography is simultaneously performed, the method allows to determine also the values of isolated renal clearance for each kidney separately. (author)

Vision/INS Integrated Navigation System for Poor Vision Navigation Environments

Directory of Open Access Journals (Sweden)

Youngsun Kim

2016-10-01

Full Text Available In order to improve the performance of an inertial navigation system, many aiding sensors can be used. Among these aiding sensors, a vision sensor is of particular note due to its benefits in terms of weight, cost, and power consumption. This paper proposes an inertial and vision integrated navigation method for poor vision navigation environments. The proposed method uses focal plane measurements of landmarks in order to provide position, velocity and attitude outputs even when the number of landmarks on the focal plane is not enough for navigation. In order to verify the proposed method, computer simulations and van tests are carried out. The results show that the proposed method gives accurate and reliable position, velocity and attitude outputs when the number of landmarks is insufficient.

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Research Consortia CF Biomarker Consortium CFTR 3-D Structure Consortium CFTR Folding Consortium Epithelial Stem Cell Consortium Mucociliary Clearance Consortium SUCCESS WITH THERAPIES RESEARCH ...

Inherited Disorders of Bilirubin Clearance

Science.gov (United States)

Memon, Naureen; Weinberger, Barry I; Hegyi, Thomas; Aleksunes, Lauren M

2016-01-01

Inherited disorders of hyperbilirubinemia may be caused by increased bilirubin production or decreased bilirubin clearance. Reduced hepatic bilirubin clearance can be due to defective 1) unconjugated bilirubin uptake and intrahepatic storage, 2) conjugation of glucuronic acid to bilirubin (e.g. Gilbert syndrome, Crigler-Najjar syndrome, Lucey-Driscoll syndrome, breast milk jaundice), 3) bilirubin excretion into bile (Dubin-Johnson syndrome), or 4) conjugated bilirubin re-uptake (Rotor syndrome). In this review, the molecular mechanisms and clinical manifestations of these conditions are described, as well as current approaches to diagnosis and therapy. PMID:26595536

Approaches towards establishing of clearance levels in Japan

International Nuclear Information System (INIS)

Sumitani, N.; Watanabe, I.; Okoshi, M.

1998-01-01

It is important to establish necessary regulatory systems for decommissioning waste management, especially to establish clearance levels from regulatory control. To establish the regulatory systems, the Nuclear Safety Commission (NSC) has been discussing the unconditional clearance levels for materials from nuclear reactors since May 1997. The NSC tries to derive unconditional clearance levels for the materials such as concrete and ferrous metal, arising from nuclear reactor decommissioning. In the derivation, both disposal and recycle/reuse of the materials are considered. Typical scenarios and parameter values for dose estimation are selected considering the Japanese natural and social conditions. Preliminary clearance levels were derived from 10 μSv/yr of individual dose criterion and deterministic analysis. For most radionuclides, the preliminary results are the same order of magnitude recommended in IAEA-TECDOC-855. Some radionuclides such as β emitters, however, are different order of magnitude from those recommended in IAEA-TECDOC-855. It is necessary that international organizations lead the discussions on the clearance levels to conclude final consensus. (author)

Green technology; only Forest Clearance is needed

Indian Academy of Sciences (India)

First page Back Continue Last page Graphics. How was Forest Clearance granted before the procedures for constitution of ESZ was completed? How was Forest Clearance granted before the procedures for constitution of ESZ was completed? How was land in Murmurwadi still under litigation made available? How was ...

Nuclear regulation. NRC's security clearance program can be strengthened

International Nuclear Information System (INIS)

Fultz, Keith O.; Kruslicky, Mary Ann; Bagnulo, John E.

1988-12-01

Because of the national security implications of its programs, the Nuclear Regulatory Commission (NRC) investigates the background of its employees and consultants as well as others to ensure that they are reliable and trustworthy. If the investigation indicates that an employee will not endanger national security, NRC grants a security clearance that allows access to classified information, material, and facilities. NRC also requires periodic checks for some clearance holders to ensure their continued clearance eligibility. The Chairman, Subcommittee on Environment, Energy, and Natural Resources, House Committee on Government Operations, asked GAO to review NRC's personnel security clearance program and assess the procedures that NRC uses to ensure that those who operate nuclear power plants do not pose a threat to the public. The Atomic Energy Act of 1954 requires NRC to conduct background investigations of its employees and consultants as well as others who have access to classified information, material, or facilities. To do this, NRC established a personnel security clearance program. Under NRC policies, a security clearance is granted after the Office of Personnel Management (OPM) or the Federal Bureau of Investigation checks the background of those applying for an NRC clearance. NRC also periodically reassesses the integrity of those holding the highest level clearance. NRC employees, consultants, contractors, and licensees as well as other federal employees hold approximately 10,600 NRC clearances. NRC does not grant clearances to commercial nuclear utility employees unless they require access to classified information or special nuclear material. However, the utilities have voluntarily established screening programs to ensure that their employees do not pose a threat to nuclear plants. NRC faces a dilemma when it hires new employees. Although its policy calls for new hires to be cleared before they start work, the security clearance process takes so long

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Cell Consortium Mucociliary Clearance Consortium SUCCESS WITH THERAPIES RESEARCH CONSORTIUM Therapeutics Development Network TDN Coordinating Center Study Services Working With the TDN Tools and Resources ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... 3-D Structure Consortium CFTR Folding Consortium Epithelial Stem Cell Consortium Mucociliary Clearance Consortium SUCCESS WITH THERAPIES RESEARCH CONSORTIUM Therapeutics Development Network TDN Coordinating Center ...

An obstacle detection system using binocular stereo fisheye lenses for planetary rover navigation

Science.gov (United States)

Liu, L.; Jia, J.; Li, L.

In this paper we present an implementation of an obstacle detection system using binocular stereo fisheye lenses for planetary rover navigation The fisheye lenses can improve image acquisition efficiency and handle minimal clearance recovery problem because they provide a large field of view However the fisheye lens introduces significant distortion in the image and this will make it much more difficult to find a one-to-one correspondence In addition we have to improve the system accuracy and efficiency for robot navigation To compute dense depth maps accurately in real time the following five key issues are considered 1 using lookup tables for a tradeoff between time and space in fisheye distortion correction and correspondence matching 2 using an improved incremental calculation scheme for algorithmic optimization 3 multimedia instruction set MMX implementation 4 consistency check to remove wrong stereo matching problems suffering from occlusions or mismatches 5 constraints of the recovery space To realize obstacle detection robustly we use the following three steps 1 extracting the ground plane parameters using Randomized Hough Transform 2 filtering the ground and background 3 locating the obstacles by using connected region detection Experimental results show the system can run at 3 2fps in 2 0GHz PC with 640X480 pixels

A study for promoting measures of social acceptance on clearance system

International Nuclear Information System (INIS)

Okoshi, Minoru; Torii, Hiroyuki; Fujii, Yasuhiko

2007-01-01

Clearance is one of the useful concepts to manage large amounts of slightly contaminated solid radioactive materials generated from the decommissioning of nuclear facilities. Cleared materials are expected to be disposed of as conventional wastes or recycled to produce consumer goods. In Japan, the legal frame-work for clearance was established in 2005 by amending the Law to regulate nuclear materials, reactors and so on. However, it is not so clear whether the general public understands clearance well. In this paper, major concerns about clearance from the general public are analyzed based on the public comments for reports on clearance prepared by the Nuclear Safety Commission and the Nuclear Institute Safety Agency. The major anxieties for clearance expressed by the general public are the safety of clearance, unknown factors of radiation effects, possibilities of excess radiation exposure due to inadequate measurements of radioactivities and fairness in decision making. In order to deal with those anxieties, some countermeasures including the confidence in nuclear operators and regulatory authorities and controllability of clearance by the general public are discussed to promote the social acceptance of clearance by the general public. (author)

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... 3-D Structure Consortium CFTR Folding Consortium Epithelial Stem Cell Consortium Mucociliary Clearance Consortium SUCCESS WITH THERAPIES RESEARCH CONSORTIUM Therapeutics Development Network TDN Coordinating Center Study ...

Intraarticular volume and clearance in human synovial effusions

International Nuclear Information System (INIS)

Wallis, W.J.; Simkin, P.A.; Nelp, W.B.; Foster, D.M.

1985-01-01

Intraarticular volumes were measured by radiolabeled albumin (RISA) distribution in chronic knee effusions from 11 rheumatoid arthritis patients and 9 osteoarthritis patients. Volumes of synovial fluid obtained at joint aspiration were substantially less than those found by RISA dilution. Up to 24 hours was needed for full distribution of RISA throughout the intraarticular compartment. Measured 123I and RISA radioactivity over the knee described monoexponential rate constants, lambda (minute-1). The clearance of 123I and RISA from synovial effusions was derived by the formulation volume (ml) X lambda (minute-1) = clearance (ml/minute). RISA clearance in rheumatoid effusions was significantly greater than that found in osteoarthritis effusions. Intraarticular volume and isotope clearance were easily quantified and provide measures for further evaluating the microvascular physiology of synovial effusions

Test Rig for Evaluating Active Turbine Blade Tip Clearance Control Concepts

Science.gov (United States)

Lattime, Scott B.; Steinetz, Bruce M.; Robbie, Malcolm G.

2003-01-01

Improved blade tip sealing in the high pressure compressor and high pressure turbine can provide dramatic improvements in specific fuel consumption, time-on-wing, compressor stall margin and engine efficiency as well as increased payload and mission range capabilities of both military and commercial gas turbine engines. The preliminary design of a mechanically actuated active clearance control (ACC) system for turbine blade tip clearance management is presented along with the design of a bench top test rig in which the system is to be evaluated. The ACC system utilizes mechanically actuated seal carrier segments and clearance measurement feedback to provide fast and precise active clearance control throughout engine operation. The purpose of this active clearance control system is to improve upon current case cooling methods. These systems have relatively slow response and do not use clearance measurement, thereby forcing cold build clearances to set the minimum clearances at extreme operating conditions (e.g., takeoff, re-burst) and not allowing cruise clearances to be minimized due to the possibility of throttle transients (e.g., step change in altitude). The active turbine blade tip clearance control system design presented herein will be evaluated to ensure that proper response and positional accuracy is achievable under simulated high-pressure turbine conditions. The test rig will simulate proper seal carrier pressure and temperature loading as well as the magnitudes and rates of blade tip clearance changes of an actual gas turbine engine. The results of these evaluations will be presented in future works.

The tear turnover and tear clearance tests - a review.

Science.gov (United States)

Garaszczuk, Izabela K; Montes Mico, Robert; Iskander, D Robert; Expósito, Alejandro Cerviño

2018-03-01

The aim is to provide a summary of methods available for the assessment of tear turnover and tear clearance rates. The review defines tear clearance and tear turnover and describes their implication for ocular surface health. Additionally, it describes main types of techniques for measuring tear turnover, including fluorescein tear clearance tests, techniques utilizing electromagnetic spectrum and tracer molecule and novel experimental techniques utilizing optical coherence tomography and fluorescein profilometry. Areas covered: Internet databases (PubMed, Science Direct, Google Scholar) and most frequently cited references were used as a principal resource of information on tear turnover rate and tear clearance rate, presenting methodologies and equipment, as well as their definition and implications for the anterior eye surface health and function. Keywords used for data-search were as follows: tear turnover, tear clearance, fluorescein clearance, scintigraphy, fluorophotometry, tear flow, drainage, tear meniscus dynamics, Krehbiel flow and lacrimal functional unit. Expert commentary: After decades, the topic of tear turnover assessment has been reintroduced. Recently, new techniques have been developed to propose less invasive, less time consuming and simpler methodologies for the assessment of tear dynamics that have the potential to be utilized in clinical practice.

Indoor wayfinding and navigation

CERN Document Server

2015-01-01

Due to the widespread use of navigation systems for wayfinding and navigation in the outdoors, researchers have devoted their efforts in recent years to designing navigation systems that can be used indoors. This book is a comprehensive guide to designing and building indoor wayfinding and navigation systems. It covers all types of feasible sensors (for example, Wi-Fi, A-GPS), discussing the level of accuracy, the types of map data needed, the data sources, and the techniques for providing routes and directions within structures.

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Community in Health Care Reform Milestones in Health Care Reform How Tax Reform Could Impact People With CF The ... Home Life With CF Treatments and Therapies Airway Clearance ...

Control algorithms for autonomous robot navigation

International Nuclear Information System (INIS)

Jorgensen, C.C.

1985-01-01

This paper examines control algorithm requirements for autonomous robot navigation outside laboratory environments. Three aspects of navigation are considered: navigation control in explored terrain, environment interactions with robot sensors, and navigation control in unanticipated situations. Major navigation methods are presented and relevance of traditional human learning theory is discussed. A new navigation technique linking graph theory and incidental learning is introduced

Effect of clearance on cartilage tribology in hip hemi-arthroplasty.

Science.gov (United States)

Lizhang, Jia; Taylor, Simon D; Jin, Zhongmin; Fisher, John; Williams, Sophie

2013-12-01

Hemi-arthroplasty of the hip (an artificial femoral head articulating against the natural acetabulum) is used to treat fractured necks of femur; however, there is evidence that articulation causes erosion of the cartilage, resulting in pain for the patient. Parameters that may influence this cartilage erosion include head material and roughness, clearance between the head and acetabulum and activity levels of the patient. This study has assessed the effect of clearance of hemi-arthroplasty articulations on the contact stress, friction and cartilage deformation in an in vitro tribological simulation of the hemi-arthroplasty joint that applied dynamic loads and motion. It has been demonstrated that peak contact stress increased from 5.6 to 10.6 MPa as radial clearance increased from small (1.8 mm). In all samples, friction factor increased with time and was significantly less with extra-large clearances compared to small (<0.6 mm), medium (0.6-1.2 mm) and large (1.2-1.8 mm) clearances. The cartilage deformation observed was significantly greater in acetabulum samples paired to give small or extra-large clearances compared to those with medium or large clearances.

A Leapfrog Navigation System

Science.gov (United States)

Opshaug, Guttorm Ringstad

There are times and places where conventional navigation systems, such as the Global Positioning System (GPS), are unavailable due to anything from temporary signal occultations to lack of navigation system infrastructure altogether. The goal of the Leapfrog Navigation System (LNS) is to provide localized positioning services for such cases. The concept behind leapfrog navigation is to advance a group of navigation units teamwise into an area of interest. In a practical 2-D case, leapfrogging assumes known initial positions of at least two currently stationary navigation units. Two or more mobile units can then start to advance into the area of interest. The positions of the mobiles are constantly being calculated based on cross-range distance measurements to the stationary units, as well as cross-ranges among the mobiles themselves. At some point the mobile units stop, and the stationary units are released to move. This second team of units (now mobile) can then overtake the first team (now stationary) and travel even further towards the common goal of the group. Since there always is one stationary team, the position of any unit can be referenced back to the initial positions. Thus, LNS provides absolute positioning. I developed navigation algorithms needed to solve leapfrog positions based on cross-range measurements. I used statistical tools to predict how position errors would grow as a function of navigation unit geometry, cross-range measurement accuracy and previous position errors. Using this knowledge I predicted that a 4-unit Leapfrog Navigation System using 100 m baselines and 200 m leap distances could travel almost 15 km before accumulating absolute position errors of 10 m (1sigma). Finally, I built a prototype leapfrog navigation system using 4 GPS transceiver ranging units. I placed the 4 units in the vertices a 10m x 10m square, and leapfrogged the group 20 meters forwards, and then back again (40 m total travel). Average horizontal RMS position

Modified Augmented Renal Clearance Score Predicts Rapid Piperacillin and Tazobactam Clearance in Critically Ill Surgery and Trauma Patients

Science.gov (United States)

2014-04-24

collision; VAP , ventilator-associated pneumonia. TABLE 2. PK Parameter Estimates for Free Piperacillin and Tazobactam in Patients Stratified by ARC Score...SOFA score are typically generated during routine care of the most severely ill patients . Positive screening test results (high ARC scores) can be...Modified Augmented Renal Clearance score predicts rapid piperacillin and tazobactam clearance in critically ill surgery and trauma patients Kevin S

Optimal motion planning using navigation measure

Science.gov (United States)

Vaidya, Umesh

2018-05-01

We introduce navigation measure as a new tool to solve the motion planning problem in the presence of static obstacles. Existence of navigation measure guarantees collision-free convergence at the final destination set beginning with almost every initial condition with respect to the Lebesgue measure. Navigation measure can be viewed as a dual to the navigation function. While the navigation function has its minimum at the final destination set and peaks at the obstacle set, navigation measure takes the maximum value at the destination set and is zero at the obstacle set. A linear programming formalism is proposed for the construction of navigation measure. Set-oriented numerical methods are utilised to obtain finite dimensional approximation of this navigation measure. Application of the proposed navigation measure-based theoretical and computational framework is demonstrated for a motion planning problem in a complex fluid flow.

Integrated navigation method of a marine strapdown inertial navigation system using a star sensor

International Nuclear Information System (INIS)

Wang, Qiuying; Diao, Ming; Gao, Wei; Zhu, Minghong; Xiao, Shu

2015-01-01

This paper presents an integrated navigation method of the strapdown inertial navigation system (SINS) using a star sensor. According to the principle of SINS, its own navigation information contains an error that increases with time. Hence, the inertial attitude matrix from the star sensor is introduced as the reference information to correct the SINS increases error. For the integrated navigation method, the vehicle’s attitude can be obtained in two ways: one is calculated from SINS; the other, which we have called star sensor attitude, is obtained as the product between the SINS position and the inertial attitude matrix from the star sensor. Therefore, the SINS position error is introduced in the star sensor attitude error. Based on the characteristics of star sensor attitude error and the mathematical derivation, the SINS navigation errors can be obtained by the coupling calculation between the SINS attitude and the star sensor attitude. Unlike several current techniques, the navigation process of this method is non-radiating and invulnerable to jamming. The effectiveness of this approach was demonstrated by simulation and experimental study. The results show that this integrated navigation method can estimate the attitude error and the position error of SINS. Therefore, the SINS navigation accuracy is improved. (paper)

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... in CF Clinical Care Guidelines Cystic Fibrosis-Related Diabetes Clinical Care Guidelines Liver Disease Clinical Care Guidelines Respiratory Care Guidelines CF Airway Clearance Therapies Clinical Care Guidelines Chronic Medications to Maintain Lung ...

2015 Annual Report on Security Clearance Determinations

Science.gov (United States)

2016-06-28

only have delegated investigative authority over their civilian employee population and therefore, can only report the overall timeliness for that...completed or pending security clearance determinations for government employees and contractors during the preceding fiscal year that have taken longer...Clearance Determinations to Congress. The IAA directs this report to include the number of United States Government (USG) employees who held a

Dynamic modelling and experimental study of cantilever beam with clearance

International Nuclear Information System (INIS)

Li, B; Jin, W; Han, L; He, Z

2012-01-01

Clearances occur in almost all mechanical systems, typically such as the clearance between slide plate of gun barrel and guide. Therefore, to study the clearances of mechanisms can be very important to increase the working performance and lifetime of mechanisms. In this paper, rigid dynamic modelling of cantilever with clearance was done according to the subject investigated. In the rigid dynamic modelling, clearance is equivalent to the spring-dashpot model, the impact of beam and boundary face was also taken into consideration. In ADAMS software, the dynamic simulation was carried out according to the model above. The software simulated the movement of cantilever with clearance under external excitation. Research found: When the clearance is larger, the force of impact will become larger. In order to study how the stiffness of the cantilever's supporting part influences natural frequency of the system, A Euler beam which is restricted by a draught spring and a torsion spring at its end was raised. Through numerical calculation, the relationship between natural frequency and stiffness was found. When the value of the stiffness is close to the limit value, the corresponding boundary condition is illustrated. An ADAMS experiment was carried out to check the theory and the simulation.

Dynamic modelling and experimental study of cantilever beam with clearance

Science.gov (United States)

Li, B.; Jin, W.; Han, L.; He, Z.

2012-05-01

Clearances occur in almost all mechanical systems, typically such as the clearance between slide plate of gun barrel and guide. Therefore, to study the clearances of mechanisms can be very important to increase the working performance and lifetime of mechanisms. In this paper, rigid dynamic modelling of cantilever with clearance was done according to the subject investigated. In the rigid dynamic modelling, clearance is equivalent to the spring-dashpot model, the impact of beam and boundary face was also taken into consideration. In ADAMS software, the dynamic simulation was carried out according to the model above. The software simulated the movement of cantilever with clearance under external excitation. Research found: When the clearance is larger, the force of impact will become larger. In order to study how the stiffness of the cantilever's supporting part influences natural frequency of the system, A Euler beam which is restricted by a draught spring and a torsion spring at its end was raised. Through numerical calculation, the relationship between natural frequency and stiffness was found. When the value of the stiffness is close to the limit value, the corresponding boundary condition is illustrated. An ADAMS experiment was carried out to check the theory and the simulation.

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... many challenges, including medical, social, and financial. By learning more about how you can manage your disease every day, you can ultimately help find a ... Cycle of Breathing Technique Airway Clearance Techniques Autogenic ...

Refrigeration system with clearance seals

International Nuclear Information System (INIS)

Holland, N. J.

1985-01-01

In a refrigeration system such as a split Stirling system, fluid seals associated with the reciprocating displacer are virtually dragless clearance seals. Movement of the displacer relative to the pressure variations in the working volume of gas is retarded by a discrete braking element. Because it is not necessary that the brake providing any sealing action, the brake can be designed for greater durability and less dependence on ambient and operating temperatures. Similarly, the clearance seal can be formed of elements having low thermal expansion such that the seal is not temperature dependent. In the primary embodiments the braking element is a split friction brake

Chaos vibration of pinion and rack steering trapezoidal mechanism containing two clearances

Science.gov (United States)

Wei, Daogao; Wang, Yu; Jiang, Tong; Zheng, Sifa; Zhao, Wenjing; Pan, Zhijie

2017-08-01

The multi-clearances of breaking type steering trapezoidal mechanism joints influences vehicle steering stability. Hence, to ascertain the influence of clearance value on steering stability, this paper takes the steering mechanism of a certain vehicle type as a prototype that can be simplified into a planar six-bar linkage, then establishes the system dynamic differential equations after considering the two clearances of tie rods and the steering knuckle arms. The influence of the clearance parameters on the movement stability of the steering mechanism is studied using a numerical computation method. Results show that when the two clearances are equal, the planar movement of the tie rods changes from period-doubling to chaos as the clearances increase. When the two clearances are 0.25 mm and 1.5 mm respectively, the planar movements of the two side tie rods come into chaos, causing the steering stability to deteriorate. Moreover, with the increase of clearances, turning moment fluctuates more intensively and the peak value increases.

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... decisions about your health care. CF Genetics: The Basics CF Mutations Video Series Find Out More About ... of Breathing Technique Airway Clearance Techniques Autogenic Drainage Basics of Lung Care Chest Physical Therapy Coughing and ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Clinician Career Development Awards Clinician Training Awards Mutation Analysis Program Network News Network News: March 2018 Network ... for airway clearance. Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... today. ANNUAL FUND Become a Corporate Supporter Cause Marketing Make a Charitable Gift Our Corporate Supporters Workplace ... for airway clearance. Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... specialized CF care and a range of treatment options. Airway Clearance Active Cycle of Breathing Technique Airway ... on their own. Share Facebook Twitter Email More options Print Share Facebook Twitter Email Print Permalink All ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Clinician Career Development Awards Clinician Training Awards Mutation Analysis Program Network News Network News: June 2018 Network ... for airway clearance. Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... a Family Parenting as an Adult With CF Treatments and Therapies People with cystic fibrosis are living ... to specialized CF care and a range of treatment options. Airway Clearance Active Cycle of Breathing Technique ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Physical Therapy Coughing and Huffing High-Frequency Chest Wall Oscillation Positive Expiratory Pressure Clinical Trials Clinical Trials ... clapping) or vibration to loosen mucus from airway walls. See how different airway clearance techniques work to ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... in part to specialized CF care and a range of treatment options. Airway Clearance Active Cycle of ... a cure for CF and supports a broad range of research initiatives to tackle the disease from ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... ACTs involve coughing or huffing . Many of them use percussion (clapping) or vibration to loosen mucus from airway walls. See how different airway clearance techniques work to help you clear the thick, sticky mucus ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Clinical Care Guidelines Liver Disease Clinical Care Guidelines Respiratory Care Guidelines CF Airway Clearance Therapies Clinical Care ... attack bacteria. Choose What's Best for You Your respiratory therapist or another member of your CF care ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Cycle of Breathing Technique Airway Clearance Techniques Autogenic Drainage Basics of Lung Care Chest Physical Therapy Coughing ... Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency Chest Wall Oscillation ( ...

Measurement with nasal scintigraphy of nasal mucociliary clearance in normal man

International Nuclear Information System (INIS)

Murai, Sumiko

1989-01-01

Nasal mucociliary function was evaluated by nasal scintigraphy in normal subjects. A microdrop of HSA or saline labelled with 99m Tc was dripped into the middle part of each middle meatus in the nasal cavity and its clearance was observed by scinticamera. The accumulated concentration of RI was determined every 30 seconds for 10 minutes. The changes of accumulated concentration were studied, and a curve of decreasing RI-counts was obtained, with the 'clearance rate' defined as 100% for the count at the initial 30 seconds and 'half time' as the time when radioactivity was reduced to one half the initial count. Nasal resistance was measured by rhinomanometry with the oscillation method. In nonsmokers, 10μl of saline was cleared (78.0±10.4%) significantly faster than 10μl of HSA (59.9±24.6%), and there was no significant difference in the clearance between 10μl and 5μl of HSA (55.9±27.7%). In smakers, the mucociliary clearance of 10μl of HSA and saline was significantly lower than in nonsmokers. The clearance of 10μl of HSA reflects a pathological state much better than that of 5μl. In nonsmokers, there is a significant negative correlation between nasal resistance and clearance rate, suggesting that the more patent the nose, the faster the mucociliary clearance. When both nostrils were closed, the clearance rate was significantly depressed. When one nostril was closed, there was no significant effect on clearance. Nasal resistance was decreased by exercise with a bicycle ergometer. Nasal mucociliary clearance was slightly decreased after exercise but not significantly so. (J.P.N.)

78 FR 77027 - Overhead Clearance (Air-Draft) Accidents

Science.gov (United States)

2013-12-20

... No. USCG-2013-0466] Overhead Clearance (Air-Draft) Accidents AGENCY: Coast Guard, DHS. ACTION... clearance (air-draft) accidents. In its petition, which calls for vessel masters to be provided with... accidents that it says were avoidable and that resulted in damage to or destruction of waterway...

The role of clearance in Germany - release of materials, buildings and sites

International Nuclear Information System (INIS)

Thierfeldt, S.

2005-01-01

Clearance in Germany is far advanced. A complex regulatory framework exists in the Radiation Protection Ordinance (RPO/Strahlenschutzverordnung, StrlSchV) since 2001 which has replaced previous recommendations on clearance issued by the German Radiation Protection Commission (Strahlenschutzkommission, SSK). A number of options exist both for unconditional clearance (e.g. of all kinds of materials with no restrictions on the destination or future use) and for clearance for a specific purpose (e.g. recycling of metal scrap). For each clearance option there is a set of nuclide specific clearance levels which have been derived on the basis of the 10 Sv/a individual dose criterion using complex radiological models which are tailored to the respective material cycles (metal scrap, buildings, building rubble, waste for disposal, sites). The clearance levels have been thoroughly reviewed by the SSK. An extensive comparison to sets of clearance levels used in other countries or issued as guidance by international bodies revealed that the correspondence between values is between good and acceptable taking into account country-specific approaches and special assumptions which would not necessarily pertain to German situations. Clearance is a major factor in the material management, especially of nuclear installations undergoing decommissioning. The variety of clearance options leaves the operator of a nuclear installation sufficient flexibility for optimisation of the material management. Clearance is of particular importance in a country like Germany where the estimated costs for a future repository are very high and the interim storage facilities for radioactive material are limited and costly. While the licensee is responsible for his material management, the issuance of a clearance permit is done by the regulatory body upon application. The regulators may choose to use the clearance levels and regulations as stipulated by the RPO, or to impose site-specific regulations on

Whole body and regional clearances of noradrenaline and adrenaline in man

DEFF Research Database (Denmark)

Christensen, N J; Galbo, H; Gjerris, A

1984-01-01

the clearance values based on arterial and venous sampling averaged 1.4 and 2.5 l/min, respectively (p less than 0.02). The difference in clearance values was due to peripheral uptake of NA averaging 45%. The plasma appearance rate on NA averaged 2.4 nmol/min before surgery and it increased to 9.5 nmol...... we found no correlation between clearance values based on venous and arterial sampling. In other experiments we measured the influence of physical exercise in young healthy subjects on the clearance rate of plasma adrenaline (A). The clearance of A, which at rest averaged 1.9 l/min tended to increase...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Make a Charitable Gift Our Corporate Supporters Workplace Engagement DONATE YOUR PROPERTY eCards for a Cure About ... airway walls. See how different airway clearance techniques work to help you clear the thick, sticky mucus ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... 3-D Structure Consortium CFTR Folding Consortium Epithelial Stem Cell Consortium Mucociliary Clearance Consortium SUCCESS WITH THERAPIES RESEARCH ... ACTs involve coughing or huffing . Many of them use percussion (clapping) or vibration to loosen mucus from ...

Online monitoring of dynamic tip clearance of turbine blades in high temperature environments

Science.gov (United States)

Han, Yu; Zhong, Chong; Zhu, Xiaoliang; Zhe, Jiang

2018-04-01

Minimized tip clearance reduces the gas leakage over turbine blade tips and improves the thrust and efficiency of turbomachinery. An accurate tip clearance sensor, measuring the dynamic clearances between blade tips and the turbine case, is a critical component for tip clearance control. This paper presents a robust inductive tip clearance sensor capable of monitoring dynamic tip clearances of turbine machines in high-temperature environments and at high rotational speeds. The sensor can also self-sense the temperature at a blade tip in situ such that temperature effect on tip clearance measurement can be estimated and compensated. To evaluate the sensor’s performance, the sensor was tested for measuring the tip clearances of turbine blades under various working temperatures ranging from 700 K to 1300 K and at turbine rotational speeds ranging from 3000 to 10 000 rpm. The blade tip clearance was varied from 50 to 2000 µm. The experiment results proved that the sensor can accurately measure the blade tip clearances with a temporal resolution of 10 µm. The capability of accurately measuring the tip clearances at high temperatures (~1300 K) and high turbine rotation speeds (~30 000 rpm), along with its compact size, makes it promising for online monitoring and active control of blade tip clearances of high-temperature turbomachinery.

Creatinine clearance during cimetidine administration for measurement of glomerular filtration rate

NARCIS (Netherlands)

van Acker, B. A.; Koomen, G. C.; Koopman, M. G.; de Waart, D. R.; Arisz, L.

1992-01-01

Creatinine clearance inaccurately estimates true glomerular filtration rate (GFR) because of tubular secretion of creatinine. We studied the ability of oral cimetidine, a blocker of tubular creatinine secretion, to improve the accuracy of measuring creatinine clearance. Clearances of inulin and

Depressed reticuloendothelial clearance of platelets in rats after trauma.

Science.gov (United States)

Kaplan, J E; Moon, D G; Minnear, F L; Saba, T M

1984-02-01

Platelet microembolization may contribute to microcirculatory and organ damage following trauma and shock. It is hypothesized that posttraumatic reticuloendothelial depression predisposes to such microembolization by failure to clear altered platelets from the circulation. The present study evaluated the short-term (1 h) clearance and organ localization of radiolabeled homologous damaged platelets in normal rats and in rats following sublethal Noble-Collip drum trauma. Platelets were collected in citrated platelet-rich plasma from normal rats and labeled with 51Cr in citrated saline. Platelets were altered by repeated centrifugation in protein-free medium. These platelets differed functionally and morphologically from normal platelets. Disappearance of iv injected damaged platelets conformed to a two-compartment exponential clearance. Velocity of clearance in the rapid compartment correlated with hepatic platelet localization, whereas velocity of clearance in the second compartment correlated with splenic platelet localization. Clearance rate of the rapid compartment was depressed at 1 h after trauma and elevated at 24 h. These changes were associated with a decrease in hepatic platelet localization at 1 h and an increase above normal at 24 h. Splenic platelet localization was decreased by 3 h following trauma. Pulmonary platelet localization was increased at all times following trauma. It is concluded that the posttrauma state is associated with a defect in the reticuloendothelial system clearance of altered platelets, which may augment embolization of platelets in the lung.

Lunar Navigation Architecture Design Considerations

Science.gov (United States)

D'Souza, Christopher; Getchius, Joel; Holt, Greg; Moreau, Michael

2009-01-01

The NASA Constellation Program is aiming to establish a long-term presence on the lunar surface. The Constellation elements (Orion, Altair, Earth Departure Stage, and Ares launch vehicles) will require a lunar navigation architecture for navigation state updates during lunar-class missions. Orion in particular has baselined earth-based ground direct tracking as the primary source for much of its absolute navigation needs. However, due to the uncertainty in the lunar navigation architecture, the Orion program has had to make certain assumptions on the capabilities of such architectures in order to adequately scale the vehicle design trade space. The following paper outlines lunar navigation requirements, the Orion program assumptions, and the impacts of these assumptions to the lunar navigation architecture design. The selection of potential sites was based upon geometric baselines, logistical feasibility, redundancy, and abort support capability. Simulated navigation covariances mapped to entry interface flightpath- angle uncertainties were used to evaluate knowledge errors. A minimum ground station architecture was identified consisting of Goldstone, Madrid, Canberra, Santiago, Hartebeeshoek, Dongora, Hawaii, Guam, and Ascension Island (or the geometric equivalent).

Intercalibration of mussel Mytilus edulis clearance rate measurements

NARCIS (Netherlands)

Kjerulf Petersen, J.; Bougrier, S.; Smaal, A.C.; Garen, P.; Robert, S.; Larsen, J.E.N.; Brummelhuis, E.B.M.

2004-01-01

Clearance rate (CR) was measured in blue mussels Mytilus edulis L. from Aiguillon Bay and the Oosterschelde using 3 different methods: the flow-through method, the bio-deposition method and the indirect or clearance method. CR differed significantly as a function of the method used and of the origin

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... a Family Parenting as an Adult With CF Treatments and Therapies People with cystic fibrosis are living longer and ... to specialized CF care and a range of treatment options. Airway Clearance Active Cycle of Breathing Technique ...

DOD PERSONNEL CLEARANCES: Additional OMB Actions Are Needed to Improve the Security Clearance Process

National Research Council Canada - National Science Library

2006-01-01

Our independent analysis of timeliness data showed that industry personnel contracted to work for the federal government waited more than one year on average to receive top secret clearances, longer...

E-navigation Services for Non-SOLAS Ships

Directory of Open Access Journals (Sweden)

Kwang An

2016-06-01

Full Text Available It is clearly understood that the main benefits of e-navigation are improved safety and better protection of the environment through the promotion of standards of navigational system and a reduction in human error. In order to meet the expectations on the benefit of e-navigation, e-navigation services should be more focused on non-SOLAS ships. The purpose of this paper is to present necessary e-navigation services for non-SOLAS ships in order to prevent marine accidents in Korean coastal waters. To meet the objectives of the study, an examination on the present navigation and communication system for non-SOLAS ships was performed. Based on the IMO's e-navigation Strategy Implementation Plan (SIP and Korea's national SIP for e-navigation, future trends for the development and implementation of e-navigation were discussed. Consequently, Electronic Navigational Chart (ENC download and ENC up-date service, ENC streaming service, route support service and communication support service based on Maritime Cloud were presented as essential e-navigation services for non-SOLAS ships. This study will help for the planning and designing of the Korean e-navigation system. It is expected that the further researches on the navigation support systems based on e-navigation will be carried out in order to implement the essential e-navigation services for non-SOLAS ships.

Assessment of renal function with the Tc-99m-MAG3 clearance

International Nuclear Information System (INIS)

Keske, U.; Corcles, M.; Andreessen, R.; Wilfling, M.; Roll, D.; Gahl, G.; Felix, R.

1990-01-01

This paper evaluates the applicability of the 99m-Tc-mercaptoacetyle-triglycine (MAG3) clearance for the documentation of renal function. Renal clearance was measured with the method of Tauxe in 699 patients during routine renal scintigraphy with 80 MBq of 99mTc-MAG3. Serum creatinine level and MAG3 clearance show an inverse correlation. Patients with an elevated serum creatinine level constantly have a lowered MAG3 clearance and vice versa. For creatinine values lower than 1.8 mg/dL, minor changes in creatinine level are accompanied by large changes in MAG3 clearance. Age (in years) dependence of MAG3 clearance was evaluated in 487 patients who showed no evidence of impaired renal function

Effects of heart rate on myocardial thallium-201 uptake and clearance

International Nuclear Information System (INIS)

Nordrehaug, J.E.; Danielsen, R.; Vik-Mo, H.

1989-01-01

The effects of heart rate on the myocardial uptake and clearance of 201 Tl were studied prospectively in seven healthy men, mean age 43 +/- 7 (s.d.) yr. Initial and delayed (3 hr) thallium images were obtained in three views after three bicycle exercise tests: to maximal, 80% and 60% of predicted maximal heart rate. The mean of three views initial myocardial 201 Tl uptake was higher at maximal than at both 80% and 60% of predicted maximal heart rate, being 81% (p less than 0.01) and 60% (p less than 0.01) of maximal activity, respectively. The myocardial activity in the delayed images was identical. There was a linear relationship between heart rate and the initial myocardial activity, r = 0.86 (p less than 0.001). The mean (range) 201 Tl clearance was 58% (51-65), 47% (34-56), and 34% (22-49) (all differences p less than 0.01), respectively. Concordance among the three individual views in estimating clearance was best for the highest exercise level. There was a linear relationship between heart rate and clearance, r = 0.80 (p less than 0.001). Clearance was altered by only 1.67 x 10%/heart bpm (0.024 hr/heart beat). Clearance in the liver, spleen and lungs increased at submaximal exercise levels. Thus, a linear relationship between heart rate and clearance is the result of changes in the initial exercise myocardial 201 Tl activity. Submaximal exercise may reduce reproducibility of clearance estimation, and the change of myocardial clearance with heart rate seems less than previously suggested

Factors affecting lower calyceal stone clearance after Extracorporeal ...

African Journals Online (AJOL)

shanker

have been identified [1,3]. These include stone characteristics, the type of lithotripter used, LPC anatomy and body habitus. For iso- lated LPC stones, the pelvicalyceal angle, infundibulum length and width are considered important determinants for stone clearance. The impact of body habitus on stone clearance has so far ...

Delayed clearance of triglyceride‐rich lipoproteins in young, healthy obese subjects†

Science.gov (United States)

Goll, R.; Lekahl, S.; Moen, O. S.; Florholmen, J.

2015-01-01

Summary Obesity is associated with the metabolic syndrome. The aims were, first, to study the postprandial triglyceride clearance in young, healthy obese subjects and, second, to investigate if fasting triglycerides can predict delayed postprandial triglyceride clearance. Eighteen apparently healthy, obese subjects with no clinical signs of metabolic disturbances participated. Controls were age‐ and sex‐matched, healthy, normal weight subjects. Subclinical markers of metabolic disturbances were assessed by measuring postprandial triglycerides in serum and in chylomicrons by oral fat tolerance test. Postprandial triglyceride clearance for 8 h was assessed indirectly as removal of the lipid from serum during the oral fat tolerance test. Insulin resistance was measured by the homeostasis model assessment of insulin resistance (HOMA‐IR). Twelve (66%) of the apparently healthy obese individuals had insulin resistance measured by HOMA‐IR. There was a delayed clearance of serum triglycerides and chylomicron triglycerides at 6 h when compared with the control group, while, at 8 h, the differences were only detected for the chylomicron triglyceride clearance. Triglyceride response was significantly greater in the obese subjects. Fasting triglycerides in upper normal level predicted a delayed postprandial triglyceride clearance and insulin resistance. In young, apparently healthy obese subjects early metabolic disturbances including insulin resistance and delayed postprandial triglyceride clearance can be detected. Fasting serum triglyceride in upper normal level predicted delayed postprandial triglyceride clearance and insulin resistance. PMID:26469529

Delayed clearance of triglyceride-rich lipoproteins in young, healthy obese subjects.

Science.gov (United States)

Larsen, M A; Goll, R; Lekahl, S; Moen, O S; Florholmen, J

2015-12-01

Obesity is associated with the metabolic syndrome. The aims were, first, to study the postprandial triglyceride clearance in young, healthy obese subjects and, second, to investigate if fasting triglycerides can predict delayed postprandial triglyceride clearance. Eighteen apparently healthy, obese subjects with no clinical signs of metabolic disturbances participated. Controls were age- and sex-matched, healthy, normal weight subjects. Subclinical markers of metabolic disturbances were assessed by measuring postprandial triglycerides in serum and in chylomicrons by oral fat tolerance test. Postprandial triglyceride clearance for 8 h was assessed indirectly as removal of the lipid from serum during the oral fat tolerance test. Insulin resistance was measured by the homeostasis model assessment of insulin resistance (HOMA-IR). Twelve (66%) of the apparently healthy obese individuals had insulin resistance measured by HOMA-IR. There was a delayed clearance of serum triglycerides and chylomicron triglycerides at 6 h when compared with the control group, while, at 8 h, the differences were only detected for the chylomicron triglyceride clearance. Triglyceride response was significantly greater in the obese subjects. Fasting triglycerides in upper normal level predicted a delayed postprandial triglyceride clearance and insulin resistance. In young, apparently healthy obese subjects early metabolic disturbances including insulin resistance and delayed postprandial triglyceride clearance can be detected. Fasting serum triglyceride in upper normal level predicted delayed postprandial triglyceride clearance and insulin resistance. © 2015 World Obesity.

Dynamic characteristics analysis of deployable space structures considering joint clearance

Science.gov (United States)

Li, Tuanjie; Guo, Jian; Cao, Yuyan

2011-04-01

The clearance in joints influences the dynamic stability and the performance of deployable space structures (DSS). A virtual experimental modal analysis (VEMA) method is proposed to deal with the effects of joint clearance and link flexibility on the dynamic characteristics of the DSS in this paper. The focus is on the finite element modeling of the clearance joint, VEMA and the modal parameters identification of the DSS. The finite element models (FEM) of the clearance joint and the deployable structure are established in ANSYS. The transient dynamic analysis is conducted to provide the time history data of excitation and response for the VEMA. The fast Fourier transform (FFT) technique is used to transform the data from time domain to frequency domain. The frequency response function is calculated to identify the modal parameters of the deployable structure. Experimental verification is provided to indicate the VEMA method is both a cost and time efficient approach to obtain the dynamic characteristics of the DSS. Finally, we analyze the effects of clearance size and gravity on the dynamic characteristics of the DSS. The analysis results indicate that the joint clearance and gravity strongly influence the dynamic characteristics of the DSS.

Indoor navigation by image recognition

Science.gov (United States)

Choi, Io Teng; Leong, Chi Chong; Hong, Ka Wo; Pun, Chi-Man

2017-07-01

With the progress of smartphones hardware, it is simple on smartphone using image recognition technique such as face detection. In addition, indoor navigation system development is much slower than outdoor navigation system. Hence, this research proves a usage of image recognition technique for navigation in indoor environment. In this paper, we introduced an indoor navigation application that uses the indoor environment features to locate user's location and a route calculating algorithm to generate an appropriate path for user. The application is implemented on Android smartphone rather than iPhone. Yet, the application design can also be applied on iOS because the design is implemented without using special features only for Android. We found that digital navigation system provides better and clearer location information than paper map. Also, the indoor environment is ideal for Image recognition processing. Hence, the results motivate us to design an indoor navigation system using image recognition.

32 CFR 644.522 - Clearance of military scrap.

Science.gov (United States)

2010-07-01

... 32 National Defense 4 2010-07-01 2010-07-01 true Clearance of military scrap. 644.522 Section 644... Excess Land and Improvements § 644.522 Clearance of military scrap. Military scrap can contain or be... destruction, by using command, of all military scrap and scrap metal from lands suitable for cultivation or...

Navigation Lights - USACE IENC

Data.gov (United States)

Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

Applicability of Clearance Automatic Laser Inspection System to Clearance Measurement of Concrete Segments

International Nuclear Information System (INIS)

Sasaki, M.; Ogino, H.; Hattori, T.

2009-01-01

In the decommissioning of a nuclear power plant, large amounts of metal scrap and concrete segments require disposal when dismantling the nuclear reactor and surrounding facilities. When their activity level is negligible or sufficiently small, they can be regarded as general industrial waste. To distinguish between radioactive and nonradioactive materials, the clearance level for each radionuclide has been determined in units of activity concentration. These clearance levels are indicated in the International Atomic Energy Agency (IAEA) Safety Standards Series No. RS-G-1.7. The Japanese regulatory authority decided in 2005 to adopt the values given in RS-G-1.7 as clearance levels in legislation. Recently, a Clearance Automatic Laser Inspection System (CLALIS) has been developed utilizing gamma-ray measurement, automatic laser shape measurement and Monte Carlo calculation. CLALIS comprises four laser scanners and eight large plastic scintillation detectors surrounded by a 5-cm-thick lead shield. Using three-dimensional (3D) laser scanning, a measurement target, which is placed on the measuring tray, is represented as a dot image. The dot image is converted into voxels after noise removal, and is written in MCNP (A General Monte Carlo N-Particle Transport Code System) input files. When the gamma-ray measurement is carried out, the MCNP calculations are also carried out to obtain the calibration factor and background (BG) correction factors. For the clearance measurement of concrete segments, the effect of gamma-rays from natural radionuclides in the measurement target, such as K-40 and the radioactive decay products of Th-232 and U-238, should be taken into account to ensure adequate waste management. Since NE102A plastic scintillation detectors are used for gamma-ray measurement in CLALIS, it is impossible to distinguish between the count rates of natural radionuclides and contaminants on the basis of gamma-ray energy information. To overcome this problem, the

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Offer their tips for fitting ACTs into daily life Airway Clearance Techniques | Webcast To learn more about how you can help your infant or child manage their lung health, watch parents of children with CF and a respiratory therapist ...

Surface navigation on Mars with a Navigation Satellite

Science.gov (United States)

Vijayaraghavan, A.; Thurman, Sam W.; Kahn, Robert D.; Hastrup, Rolf C.

Radiometric navigation data from the Deep Space Network (DSN) stations on the earth to transponders and other surface elements such as rovers and landers on Mars, can determine their positions to only within a kilometer in inertial space. The positional error is mostly in the z-component of the surface element parallel to the Martian spin-axis. However, with Doppler and differenced-Doppler data from a Navigation Satellite in orbit around Mars to two or more of such transponders on the planetary surface, their positions can be determined to within 15 meters (or 20 meters for one-way Doppler beacons on Mars) in inertial space. In this case, the transponders (or other vehicles) on Mars need not even be capable of directly communicating to the earth. When the Navigation Satellite data is complemented by radiometric observations from the DSN stations also, directly to the surface elements on Mars, their positions can be determined to within 3 meters in inertial space. The relative positions of such surface elements on Mars (relative to one another) in Mars-fixed coordinates, however, can be determined to within 5 meters from simply range and Doppler data from the DSN stations to the surface elements. These results are obtained from covariance studies assuming X-band data noise levels and data-arcs not exceeding 10 days. They are significant in the planning and deployment of a Mars-based navigation network necessary to support real-time operations during critical phases of manned exploration of Mars.

Clearance level and industrial waste management

International Nuclear Information System (INIS)

Asano, Toichi

1999-01-01

Defining the clearance level enables the radioactive waste with lower radioactivity than a certain level to be the general industrial waste and therefore consideration for public acceptance is essential. For this, it is necessary to understand laws concerning not only atomic power and radioactivity but also disposal and cleaning of general waste. It is also necessary that the waste below the clearance level should be as much as possible handled in the modern common concept of recycling of resources. In 1996, the weight of industrial waste was about 400 million tons, of which 40% was disposed by burning and dehydration, 39% was re-used and 21% was subjected to the final disposal like reclamation. Reduction, re-use and recycling of the generated waste are required for making the society with recycling of resources. Scrap concrete materials below the clearance level of 0.6 million tons are estimated to be generated by dismantling the light water reactor of 1 million kW output and profitable technology for recycling the scrap is under investigation. (K.H.)

Factors Associated with Spontaneous Clearance of Hepatitis C Virus in Chinese Population

Directory of Open Access Journals (Sweden)

Fei Kong

2014-01-01

Full Text Available Hepatitis C virus (HCV infections spontaneously clear in approximately 15–45% of infected individuals. Factors which influence spontaneous HCV clearance remain to be identified. The purpose of the present study was to identify variables associated with spontaneous HCV clearance in a referred population of Chinese patients. The prevalence of host, viral, and environmental factors known to influence the outcome of HCV infections was compared in 92 HCV spontaneous clearance subjects and 318 HCV persistent infection subjects. Univariate and multivariate analyses were performed to identify those factors associated with spontaneous HCV clearance. In univariate analysis, female gender, a history of icteric hepatitis, serologic evidence of concurrent HBV infection, and rs12979860 CC genotype were positively associated with spontaneous HCV clearance, while alcohol consumption was negatively associated with clearance. In multivariate analysis, female gender, a history of icteric hepatitis, concurrent HBV infection, and rs12979860 CC genotype remained independent variables associated with spontaneous HCV clearance. Spontaneous HCV clearance is more likely to occur in females, subjects with a history of icteric hepatitis, HBV coinfections, and those with the rs12979860 CC genotype.

Semiotic resources for navigation

DEFF Research Database (Denmark)

Due, Brian Lystgaard; Lange, Simon Bierring

2018-01-01

This paper describes two typical semiotic resources blind people use when navigating in urban areas. Everyone makes use of a variety of interpretive semiotic resources and senses when navigating. For sighted individuals, this especially involves sight. Blind people, however, must rely on everything...... else than sight, thereby substituting sight with other modalities and distributing the navigational work to other semiotic resources. Based on a large corpus of fieldwork among blind people in Denmark, undertaking observations, interviews, and video recordings of their naturally occurring practices...... of walking and navigating, this paper shows how two prototypical types of semiotic resources function as helpful cognitive extensions: the guide dog and the white cane. This paper takes its theoretical and methodological perspective from EMCA multimodal interaction analysis....

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... how you can help your infant or child manage their lung health, watch parents of children with CF and a respiratory therapist talk about the different techniques they use for airway clearance. Facebook Twitter Email More Related Content Medications Autogenic Drainage ...

49 CFR 236.22 - Semaphore signal arm; clearance to other objects.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Semaphore signal arm; clearance to other objects... Rules and Instructions: All Systems Roadway Signals and Cab Signals § 236.22 Semaphore signal arm; clearance to other objects. At least one-half inch clearance shall be provided between semaphore signal arm...

Whole body and regional clearances of noradrenaline and adrenaline in man

DEFF Research Database (Denmark)

Christensen, N J; Galbo, H; Gjerris, Anne Cathrine Roslev

1984-01-01

we found no correlation between clearance values based on venous and arterial sampling. In other experiments we measured the influence of physical exercise in young healthy subjects on the clearance rate of plasma adrenaline (A). The clearance of A, which at rest averaged 1.9 l/min tended to increase...

Using Terrestrial Laser Scanners to Calculate and Map Vertical Bridge Clearance

Science.gov (United States)

Zhang, C.; Arditi, D.; Chen, Z.

2013-08-01

The vertical clearance of a bridge over a highway is important in preventing oversized vehicles from hitting the bridge. The vertical clearance of a bridge is traditionally measured by using surveying equipment such as leveling rods and total stations. Typically, measurements are taken at multiple locations in order to determine the minimum vertical clearance under the bridge. This process is time and labor consuming. Also, these measurements may not be accurate because of the traffic, the uneven surface, and the reading error caused by the surveyor. Additionally, when one is faced with a multitude of reports especially in large projects with multiple ramps and bridges, it is not easy and it often takes a long time to find the bridge under study. This research provides a highly accurate measurement of the vertical bridge clearance by using terrestrial laser scanners. The clearance can be measured in the office by processing the collected point cloud data. The minimum vertical clearance is easily identified and the measurement is visualized and geo-referenced. An approach to reduce data noise caused by traffic is also introduced in this study. In addition, to help reduce the confusion of finding the bridge under study and to facilitate access to the clearance data, the clearance measurements are geo-referenced to an online mapping system. This system allows access to the final deliverable very easily through a single web portal. Finally, Illinois Department of Transportation's Circle Interchange is used to demonstrate this new method.

33 CFR 401.54 - Interference with navigation aids.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b) No...

Respiratory clearance of aerosolized radioactive solutes of varying molecular weight

International Nuclear Information System (INIS)

Huchon, G.J.; Montgomery, A.B.; Lipavsky, A.; Hoeffel, J.M.; Murray, J.F.

1987-01-01

To determine the influence of varying molecular weight (mol wt) on respiratory clearance of aerosolized solutes, we studied eight radiopharmaceuticals, each administered to four dogs: sodium /sup 99m/Tc pertechnetate (TcO4), /sup 99m/Tc glucoheptonate ([/sup 99m/Tc]GH), 51Cr-ethylenedinitrotetraacetate ([51Cr]EDTA), /sup 99m/Tc diethylenetriaminepentaacetate ([99mTc] DTPA), 111 In diethylenetriaminepentaacetate ([ 111 In]DTPA), 67 Ga desferoxaminemesylate ([ 67 Ga]DFOM), /sup 99m/Tc dextran ([/sup 99m/Tc]DX) and 111 In transferrin ([ 111 In]TF). After aerosolization (0.8 m MMD, 2.4 GSD), clearance was determined for 30 min and then corrected by intravenous injection for nonairspace radioactivity. In-TF clearance (0.11 +/- 0.10%/min) was lower than TcO4 (6.32 +/- 0.62%/min), [/sup 99m/Tc]GH (1.50 +/- 0.37%/min), [ 51 Cr]EDTA (2.38 +/- 1.02%/min), [/sup 99m/Tc]DTPA (3.51 +/- 0.40%/min), [ 111 In]DTPA (2.35 +/- 0.42%/min), [ 67 Ga] DFOM (1.99 +/- 0.49%/min) and [/sup 99m/Tc]DX (1.81 +/- 0.75%/min) clearances (p less than 0.001). TcO4 clearance was higher than others (p less than 0.001). Technetium binding to DX was unsatisfactory; aerosolization caused unbinding from DTPA. We conclude that respiratory clearance of large mol wt solutes within 30 min is negligible and, that clearance of molecules between 347-5099 daltons differs greatly, suggesting that binding and/or intrapulmonary retention affect transfer

Comparison of German and international clearance regulations - chances and limits for harmonization

International Nuclear Information System (INIS)

Thierfeldt, S.; Schartmann, F.

2005-01-01

The regulations on clearance in the German nuclear regulatory framework (especially sect. 29 and Annexes III and IV of the Radiation Protection Ordinance) are comprehensive and well founded. Germany has developed some of its clearance levels in advance of recommendations issued by the EC. Therefore, there are differences between the German and international clearance regulations. That has been investigated by a working group on clearance of the German Commission on Radiological Protection (SSK) which has performed an analysis of differences and their reasons for clearance levels in Germany and other countries (UK, The Netherlands, Sweden, USA and others). Differences can mainly be explained by country specific approaches in scenarios. Differences especially for the most relevant nuclides are not significant from a radiological point of view. The level of radiological protection (trivial dose range, a few 10 μSv/a) is guaranteed in all countries. The international discussion on the international harmonisation of clearance levels (mainly within the scope of the OECD/NEA and IAEA) can be enlightened on the basis of these results. This discussion concentrates on the question how far a harmonisation of clearance level values is actually necessary and possible. The IAEA Safety Guide RS-G-1.7 'Application of the concepts of exclusion, exemption and clearance' is of particular importance, because it proposes a set of values which might in the long-term take the role of international unconditional clearance levels. International harmonisation is only relevant for unconditional clearance of those materials, which are traded in large quantities among countries, in particular metal scrap. Harmonisation of the values to the same order of magnitude is sufficient. (orig.)

Discrepancy between circadian rhythms of inulin and creatinine clearance

NARCIS (Netherlands)

van Acker, B. A.; Koomen, G. C.; Koopman, M. G.; Krediet, R. T.; Arisz, L.

1992-01-01

To elucidate the disparity between circadian rhythmicity of inulin and creatinine clearance, we simultaneously measured inulin and creatinine clearances every 3 hours during 1 day in 14 normal subjects and in 8 patients with nephrotic syndrome. All patients and normal subjects had a circadian rhythm

Lung clearance of 99m Tc- DTPA in systemic lupus erythematous

International Nuclear Information System (INIS)

Dalcin, P.T.R; Barreto, S.S.M.; Xavier, R.M.; Brenol, J.C.T.; Cunha, R.D.; Marroni, B.J.

2002-01-01

The early demonstration of lung involvement in systemic lupus erythematosus (SLE) patients is a difficult but important task. In the present study we attempted to identify abnormalities in pulmonary clearance of 99 mTc-DTPA in SLE, correlating their clearance data with clinical findings and disease activity. Forty-six consecutive SLE patients with and without active disease (LACC score) and 30 normal volunteers were studied. All subjects were submitted to pulmonary scintigraphy with 99 mTc-DTPA to evaluate the pulmonary clearance, and to a chest X-ray, and SLE patients were submitted to tests of disease activity, spirometry, arterial blood gases and tests to assess acute-phase proteins. Pulmonary clearance was faster in SLE patients with active disease when compared to normal controls [half-life of 67.04 min (51.52-82.55 min) in active SLE versus 85.87 min (78.85-92.87 min) in controls, P<0.05] and there was a higher frequency of abnormal clearance rates in patients with active disease (11 of 26 patients, 42.3%) when compared with SLE patients without disease activity (2 of 20 patients, 10%) (P = 0.04). A significant correlation was observed between the clearance rates and cough (P<0.05), but not between the clearance rates and dyspnoea symptoms or radiological findings, duration of SLE disease, antinuclear antibody titers and patterns, C-reactive protein or anti-double stranded DNA antibodies. We conclude that the pulmonary clearance of 99 m Tc-DTPA is increased in SLE patients with active disease. (author)

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... cystic fibrosis. CF CARE CENTER finder We provide funding for and accredit more than 120 care centers ... Community in Health Care Reform Milestones in Health Care Reform How Tax Reform Could Impact People With CF The ... Home Life With CF Treatments and Therapies Airway Clearance ...

48 CFR 32.502-2 - Contract finance office clearance.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Contract finance office clearance. 32.502-2 Section 32.502-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... finance office clearance. The contracting officer shall obtain the approval of the contract finance office...

48 CFR 832.502-2 - Contract finance office clearance.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contract finance office clearance. 832.502-2 Section 832.502-2 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... finance office clearance. Contracting officers must obtain approval from the DSPE before taking the...

Real-time precision pedestrian navigation solution using Inertial Navigation System and Global Positioning System

OpenAIRE

Yong-Jin Yoon; King Ho Holden Li; Jiahe Steven Lee; Woo-Tae Park

2015-01-01

Global Positioning System and Inertial Navigation System can be used to determine position and velocity. A Global Positioning System module is able to accurately determine position without sensor drift, but its usage is limited in heavily urbanized environments and heavy vegetation. While high-cost tactical-grade Inertial Navigation System can determine position accurately, low-cost micro-electro-mechanical system Inertial Navigation System sensors are plagued by significant errors. Global Po...

Secretion clearance strategies in Australian and New Zealand Intensive Care Units.

Science.gov (United States)

Ntoumenopoulos, George; Hammond, Naomi; Watts, Nicola R; Thompson, Kelly; Hanlon, Gabrielle; Paratz, Jennifer D; Thomas, Peter

2017-06-26

To describe the processes of care for secretion clearance in adult, intubated and mechanically ventilated patients in Australian and New Zealand Intensive Care Units (ICUs). A prospective, cross-sectional study was conducted through the Australian and New Zealand Intensive Care Society Clinical Trials Group (ANZICS CTG) Point Prevalence Program. Forty-seven ICUs collected data from 230 patients intubated and ventilated on the study day. Secretion clearance techniques beyond standard suctioning were used in 84/230 (37%) of patients during the study period. Chest wall vibration 34/84 (40%), manual lung hyperinflation 24/84 (29%), chest wall percussion 20/84 (24%), postural drainage/patient positioning 17/84 (20%) and other techniques including mobilisation 15/84 (18%), were the most common secretion clearance techniques employed. On average (SD), patients received airway suctioning 8.8 (5.0) times during the 24-h study period. Mucus plugging events were infrequent (2.7%). The additional secretion clearance techniques were provided by physiotherapy staff in 24/47 (51%) ICUs and by both nursing and physiotherapy staff in the remaining 23/47 (49%) ICUs. One-third of intubated and ventilated patients received additional secretion clearance techniques. Mucus plugging events were infrequent with these additional secretion clearance approaches. Prospective studies must examine additional secretion clearance practices, prevalence of mucus plugging episodes and impact on patient outcomes. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Influence of peak exercise heart rate on normal thallium-201 myocardial clearance

International Nuclear Information System (INIS)

Kaul, S.; Chesler, D.A.; Pohost, G.M.; Strauss, H.W.; Okada, R.D.; Boucher, C.A.

1986-01-01

Measurement of myocardial clearance rates between initial and delayed images is a major justification for adding computer quantification to the interpretation of exercise 201 TI images. To clarify the range of normal thallium clearance and its relationship to the level of exercise achieved, exercise thallium images in 89 normal subjects were analyzed: 45 asymptomatic subjects with less than 1% probability of coronary artery disease (CAD) (Group I), and 44 patients with chest pain found to have no significant CAD on angiography (Group II). Mean initial regional thallium uptake was similar in the two groups, but myocardial thallium clearance (mean +/- 1 s.d.) was slower in Group II, expressed as a longer half-life in the myocardium (8.2 +/- 7.6 hr compared with 3.4 +/- 0.7 hr p less than 0.001). Analysis of variance using ten clinical and exercise variables as covariates showed that the slower clearance in Group II was related to a lower peak exercise heart rate (HR) (154 +/- 27 compared with 183 +/- 11, respectively, p less than 0.001). By linear regression analysis, a decrease in peak HR of 1 beat/min was associated with a slower thallium clearance (longer half-life) of 0.05 hr. Using this formula, the clearance value in each patient was then corrected for peak exercise heart rate by decreasing measured clearance by 0.05 hr multiplied by the amount peak exercise heart rate which was below 183 (the mean value in Group I). There were no differences in the corrected clearance between the two groups. We conclude that thallium myocardial clearance after exercise is related in part to factors other than the presence of CAD, being slower when peak exercise HR is lower. Therefore, thallium clearance rates alone uncorrected for peak exercise heart rate should be used with caution when diagnosing CAD

A Study to Determine Clearance Levels of Radioactive Wastes in Kenya

Energy Technology Data Exchange (ETDEWEB)

Mukakaa, Zaphania O. [KAIST, Daejeon (Korea, Republic of); Kim, Sung Il [KINS, Daejeon (Korea, Republic of)

2015-10-15

Due to lack of a radioactive waste disposal facility in Kenya, radioactive wastes are stored in a bonded warehouse until such a time when their activity is low and they meet the criterion for clearance. The International Atomic Energy Agency (IAEA) has established activity concentrations of radionuclides to act as a universal guideline or standard for clearance in member countries. Radioactive wastes whose activity would yield a trivial risk to the people and environment, i.e. with an annual dose below 10 µSv are usually cleared from regulatory control with no further regulatory control mechanisms being taken. The Radiation Protection Board currently depends on the IAEA's generic clearance level activity concentrations for purposes of clearing the radiation wastes within its inventory. This study aims to determine activity concentrations of radionuclides in the Kenyan inventory that correspond to the clearance level dose of 10 µSv/a as set by the IAEA. The RESidual RADioactivity (RESRAD) computer code, an important tool developed in 1989 to aid in evaluation of sites with radioactive contamination, will aid in modeling these clearance level values using a pathways analysis method and available site-specific data from Kenya. Afterwards, the obtained clearance level values will be compared with the IAEA's generic clearance level values of the corresponding radionuclides. The results modeled using the RESRAD code are conservative. For most of the radionuclides in the Kenyan inventory, the values do correspond with the IAEA standard generic clearance level values, albeit with minor differences. For most of the radionuclides, the difference is within the acceptable uncertainty limit. For these low probability events the effective dose resulting from them should not exceed 1 mSv per year. Thus, consideration was given to doses to the skin and an equivalent dose to the skin of 50 mSv per year was duly used in estimating the clearance level activities. The

Factors contributing to delay in parasite clearance in uncomplicated falciparum malaria in children

Directory of Open Access Journals (Sweden)

Sijuade Abayomi

2010-02-01

Full Text Available Abstract Background Drug resistance in Plasmodium falciparum is common in many endemic and other settings but there is no clear recommendation on when to change therapy when there is delay in parasite clearance after initiation of therapy in African children. Methods The factors contributing to delay in parasite clearance, defined as a clearance time > 2 d, in falciparum malaria were characterized in 2,752 prospectively studied children treated with anti-malarial drugs between 1996 and 2008. Results 1,237 of 2,752 children (45% had delay in parasite clearance. Overall 211 children (17% with delay in clearance subsequently failed therapy and they constituted 72% of those who had drug failure, i.e., 211 of 291 children. The following were independent risk factors for delay in parasite clearance at enrolment: age less than or equal to 2 years (Adjusted odds ratio [AOR] = 2.13, 95% confidence interval [CI]1.44-3.15, P 50,000/ul (AOR = 2.21, 95% CI = 1.77-2.75, P 20000/μl a day after treatment began, were independent risk factors for delay in clearance. Non-artemisinin monotherapies were associated with delay in clearance and treatment failures, and in those treated with chloroquine or amodiaquine, with pfmdr 1/pfcrt mutants. Delay in clearance significantly increased gametocyte carriage (P Conclusion Delay in parasite clearance is multifactorial, is related to drug resistance and treatment failure in uncomplicated malaria and has implications for malaria control efforts in sub-Saharan Africa.

Effect of glucose-insulin-potassium infusion on thallium myocardial clearance

International Nuclear Information System (INIS)

Wilson, R.A.; Okada, R.D.; Strauss, H.W.; Pohost, G.M.

1983-01-01

Factors influencing the rate of 201 Tl clearance from the myocardium have not been clearly defined. This study determined the effect of an intravenous infusion of glucose-insulin-potassium (GIK) on the net 201 Tl clearance rates from myocardium with and without initial 201 Tl loading. Anesthetized open-chest dogs underwent 5 min of left anterior descending coronary artery occlusion and intravenous 201 Tl was injected and the occlusion released 5 min later. Thirty minutes after 201 Tl injection, 30 ml of either GIK (nine dogs) or saline (five dogs) was infused intravenously. The clearance rates of 201 Tl from the anterior wall (without initial 201 Tl loading) and from the posterior wall (with initial 201 Tl loading) were monitored with miniaturized cadmium telluride detectors placed on the myocardium. Calculation of net myocardial clearance rates was performed by linear regression analysis from serial 1 min counts. Compared with saline infusion, GIK increased the net clearance of 201 Tl from both myocardial regions with and without initial loading. The most marked change induced by GIK infusion was in the myocardial region without initial 201 Tl loading; a net increase in 201 Tl activity (72 +/- 42 cpm/30 min) was converted into a net loss (-594 +/- 228 cpm/30 min). There was no significant change in 201 Tl clearance after the saline infusion. Heart rate, aortic and left atrial pressure, sonomicrometer-measured transmural myocardial wall thickness, microsphere-determined myocardial blood flow, and blood glucose and potassium concentrations did not change significantly during GIK or saline infusions. Thus, GIK infusion appears to increase net 201 Tl clearance from myocardial zones with and without initial 201 Tl loading

Navigating oceans and cultures: Polynesian and European navigation systems in the late eighteenth century

Science.gov (United States)

Walker, M.

2012-05-01

Significant differences in the rotation of the celestial dome between the tropical and temperate zones did not stop the peoples of either the tropical Pacific or temperate Europe from using geocentric astronomy to guide exploration of the oceans. Although the differences in the night sky contributed to differences between the Pacific Island and European systems for navigation at sea, the two navigation systems exhibit substantial similarities. Both systems define positions on the surface of the Earth using two coordinates that vary at right angles to each other and use stars, and to a lesser extent the sun, to determine directions. This essay explores similarities and differences in the use of geocentric astronomy for navigation at sea by the peoples of Polynesia and Europe in the late eighteenth century. Captain Cook's orders to discover the unknown southern continent after observing the transit of Venus combined with differences in language and culture to obscure the deeper similarities between the navigation systems used by Cook and the Polynesians. Although it was a further 200 years before anthropologists studied Pacific navigation, collaborations in voyaging with communities in Oceania demonstrated the effectiveness of Pacific navigation systems, revived interest in traditional voyaging in island communities around the Pacific, and potentially open the way for further collaborations in other areas.

Comparison of measurements of plasma clearance of Mebrofenine and of indocyanine green

International Nuclear Information System (INIS)

Maurel, G.; Coutris, G.; Vaubourdolle, M.; Attal, P.; Patureau, R.; Tabsoba, Th.; Mensch, B.; Askienazy, Pr.S.

1997-01-01

The importance of clearance measurements in evaluating renal or hepatic function needs not further demonstration. The isotopic methods were proved in renal exploration but their utilization in exploration of hepato-biliary function needs to be evaluated. In this work we have compared the measurement of plasma clearance by Mebrofenine, a radiopharmaceutical of specifically hepatic elimination, with the reference method, the clearance of indocyanine green. On the basis of scintigraphic data from 23 patients who benefited by a hepato-biliary exploration by Mebrofenine- 99m Tc for pre-surgery account and surveillance, we have determined the plasma clearance of this radiopharmaceutical. The method makes use of the curve of normalized cardiac activity by a blood sampling, taken 60 minutes after injection. The measurement of the clearance of indocyanine green was effected within a delay inferior to 1 month from the moment of biliary scintigraphy. The average clearance of Mebrofenine- 99m Tc is of 553 ml/min for 1.73 m 2 of corporal surface (typical interval is 374 ml/min), the value of indocyanine green is of 450 ml/min (typical interval is 229 ml/min). The two measurements of clearance are correlated (p = 0.05). In conclusion, the measurement of clearance by Mebrofenine- 99m appears to be adapted to the evaluation of hepato-biliary function

48 CFR 1432.502-2 - Contract finance office clearance.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contract finance office clearance. 1432.502-2 Section 1432.502-2 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR... finance office clearance. The CO shall obtain approval of the bureau finance office prior to taking...

Determining vancomycin clearance in an overweight and obese population.

Science.gov (United States)

Leong, Julie V B; Boro, Maureen S; Winter, Michaele

2011-04-01

Two methods of calculating vancomycin clearance were compared to determine the best body weight measure to use when dosing vancomycin for overweight and obese patients. Hospitalized veterans weighing more than 120% of their ideal body weight (IBW) with serum vancomycin concentrations (SVCs) drawn between January 1, 2003, and June 30, 2005, were eligible for study inclusion. Exclusion criteria included weight of more than 300% the IBW, unstable renal function, dialysis, uncertain vancomycin dosing or sampling times, and distribution-phase sampling. Data from January 1 through December 31, 2003 (phase 1) determined the best-fit weight for vancomycin clearance for the Leonard and Boro method. The bias and precision of the modified Leonard and Boro method using the best-fit weight for vancomycin clearance were then compared with those of the Rushing and Ambrose method for predicting SVCs from January 1, 2004, through June 30, 2005 (phase 2). Forty-eight patients were included in phase 1, with 67 SVCs for analysis. During phase 1, adjusted body weight (ABW), using the Leonard and Boro method, was superior in predicting vancomycin clearance and the resultant SVCs. A total of 96 patients were included in phase 2 of the study, with 160 SVCs for analysis. The modified Leonard and Boro method was significantly more precise than the Rushing and Ambrose method in predicting vancomycin clearance. Use of ABW proved to be superior compared with total body weight when estimating vancomycin clearance in overweight and obese patients. While there was no difference in bias between methods, the modified Leonard and Boro method was significantly more precise than the Rushing and Ambrose method in predicting SVCs when dosing vancomycin for obese patients.

Tip clearance effect on through-flow and performance of a centrifugal compressor

International Nuclear Information System (INIS)

Eum, Hark Jin; Kang, Young Seok; Kang, Shin Hyoung

2004-01-01

Numerical simulations have been performed to investigate tip clearance effect on through-flow and performance of a centrifugal compressor which has the same configuration of impeller with six different tip clearances. Secondary flow and loss distribution have been surveyed to understand the flow mechanism due to the tip clearance. Tip leakage flow strongly interacts with mainstream flow and considerably changes the secondary flow and the loss distribution inside the impeller passage. A method has been described to quantitatively estimate the tip clearance effect on the performance drop and the efficiency drop. The tip clearance has caused specific work reduction and additional entropy generation. The former, which is called inviscid loss, is independent of any internal loss and the latter, which is called viscous loss, is dependent on every loss in the flow passage. Two components equally affected the performance drop as the tip clearances were small, while the efficiency drop was influenced by the viscous component alone. The additional entropy generation was modeled with all the kinetic energy of the tip leakage flow. Therefore, the present paper can provide how to quantitatively estimate the tip clearance effect on the performance and efficiency

Multi-Flight-Phase GPS Navigation Filter Applications to Terrestrial Vehicle Navigation and Positioning

Science.gov (United States)

Park, Young W.; Montez, Moises N.

1994-01-01

A candidate onboard space navigation filter demonstrated excellent performance (less than 8 meter level RMS semi-major axis accuracy) in performing orbit determination of a low-Earth orbit Explorer satellite using single-frequency real GPS data. This performance is significantly better than predicted by other simulation studies using dual-frequency GPS data. The study results revealed the significance of two new modeling approaches evaluated in the work. One approach introduces a single-frequency ionospheric correction through pseudo-range and phase range averaging implementation. The other approach demonstrates a precise axis-dependent characterization of dynamic sample space uncertainty to compute a more accurate Kalman filter gain. Additionally, this navigation filter demonstrates a flexibility to accommodate both perturbational dynamic and observational biases required for multi-flight phase and inhomogeneous application environments. This paper reviews the potential application of these methods and the filter structure to terrestrial vehicle and positioning applications. Both the single-frequency ionospheric correction method and the axis-dependent state noise modeling approach offer valuable contributions in cost and accuracy improvements for terrestrial GPS receivers. With a modular design approach to either 'plug-in' or 'unplug' various force models, this multi-flight phase navigation filter design structure also provides a versatile GPS navigation software engine for both atmospheric and exo-atmospheric navigation or positioning use, thereby streamlining the flight phase or application-dependent software requirements. Thus, a standardized GPS navigation software engine that can reduce the development and maintenance cost of commercial GPS receivers is now possible.

Tear clearance implications for ocular surface health.

Science.gov (United States)

de Paiva, Cintia Sade; Pflugfelder, Stephen C

2004-03-01

Tear clearance/turnover provides a global assessment of the function of the lacrimal functional unit and of tear exchange on the ocular surface. It is an indirect measure of dry eye induced inflammation on the ocular surface. It shows better correlation with the severity of ocular irritation symptoms and corneal epithelial disease in dry eye than the Schirmer 1 test. Delayed tear clearance may prove to be the best measure for identifying patients with tear film disorders who may respond to anti-inflammatory therapy.

Clearance of Tc-99m DTPA in hemodialysis and peritoneal dialysis: concise communication

International Nuclear Information System (INIS)

Wainer, E.; Boner, G.; Lubin, E.; Rosenfeld, J.B.

1981-01-01

The clearance of Tc-99m DTPA was studied in 14 patients undergoing hemodialysis (HD) or peritoneal dialysis (PD). Mean Tc-99m DTPA clearance during HD was 37.8% +/- 10.1 of creatinine clearance. Mean Tc-99m DTPA clearance in PD was 65.1% +/- 10.3 of creatinine clearance. Tc-99m DTPA, with a larger molecular weight than that of creatinine, is cleared relatively better during PD than during HD. Thus Tc-99m DTPA may be used in the assessment of the effectiveness of different dialytic treatments for substances of similar molecular weight. In addition, our study shows that clearance of DTPA both in HD and PD is sufficiently high to allow the removal of this chelating agent in patients with renal failure

Usability Testing of Two Ambulatory EHR Navigators.

Science.gov (United States)

Hultman, Gretchen; Marquard, Jenna; Arsoniadis, Elliot; Mink, Pamela; Rizvi, Rubina; Ramer, Tim; Khairat, Saif; Fickau, Keri; Melton, Genevieve B

2016-01-01

Despite widespread electronic health record (EHR) adoption, poor EHR system usability continues to be a significant barrier to effective system use for end users. One key to addressing usability problems is to employ user testing and user-centered design. To understand if redesigning an EHR-based navigation tool with clinician input improved user performance and satisfaction. A usability evaluation was conducted to compare two versions of a redesigned ambulatory navigator. Participants completed tasks for five patient cases using the navigators, while employing a think-aloud protocol. The tasks were based on Meaningful Use (MU) requirements. The version of navigator did not affect perceived workload, and time to complete tasks was longer in the redesigned navigator. A relatively small portion of navigator content was used to complete the MU-related tasks, though navigation patterns were highly variable across participants for both navigators. Preferences for EHR navigation structures appeared to be individualized. This study demonstrates the importance of EHR usability assessments to evaluate group and individual performance of different interfaces and preferences for each design.

Effect of isolated hepatic ischemia on organic anion clearance and oxidative metabolism.

Science.gov (United States)

Minard, G; Bynoe, R; Wood, G C; Fabian, T C; Croce, M; Kudsk, K A

1992-04-01

Hepatic failure is frequently seen following severe hemorrhagic shock, sepsis, and trauma. Clearance of various drugs has been used to evaluate hepatocellular dysfunction, including indocyanine green (ICG), an organic anionic dye that is transported similarly to bilirubin, and antipyrine (AP), a marker of oxidative phosphorylation. Previous investigators have noted a decrease in ICG excretion following systemic hemorrhage. The effect of isolated hepatic ischemia on the clearances of ICG and AP was studied in 16 pigs after 90 minutes of vascular occlusion to the liver. Antipyrine clearance decreased almost 50% from baseline values at 24 and 72 hours after the ischemia procedure, indicating a significant depression in the cytochrome P-450 system. On the other hand, ICG clearance did not change significantly. In conclusion, ICG clearance is not depressed after isolated hepatic ischemia in pigs. Changes in organic anion clearance after systemic hemorrhage may be because of release of toxic products from ischemic peripheral tissue.

Clearance of 99mTc-DTPA and experimentally increased alveolar surfactant content

International Nuclear Information System (INIS)

Bos, J.A.H.; Wollmer, P.; Bakker, W.; Hannappel, E.; Lachmann, B.

1992-01-01

The authors measured clearance of 99m Tc-labeled diethylenetriamine pentaacetic acid ( 99m Tc-DTPA) in rabbits with experimentally increased alveolar surfactant content. In one group of animals, surfactant production was increased by treatment with ambroxol, and another group of animals was treated with tracheal instillation of natural surfactant. A group of untreated control animals and animals treated with instillation of saline were also studied. Clearance was measured during standard conditions of mechanical ventilation and during ventilation with large tidal volumes. In ambroxol- and surfactant-treated groups, clearance rate was reduced compared with untreated control animals. In contrast, clearance rate increased after saline instillation. The differences were observed at both modes of ventilation. The findings indicate that the pulmonary surfactant system is a rate-limiting factor for the clearance of 99m Tc-DTPA and that the volume dependence of clearance is not explained by stretching of the alveolar wall only. 28 refs., 2 figs., 1 tab

75 FR 50884 - Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector...

Science.gov (United States)

2010-08-18

... 3 and 165 to reflect changes in Coast Guard internal organizational structure. Sector Portland and... 1625-ZA25 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector... Waters; Technical, Organizational, and Conforming Amendments, Sector Columbia River.'' 2. On page 48564...

Optimizing Dredge-and-Dump Activities for River Navigability Using a Hydro-Morphodynamic Model

Directory of Open Access Journals (Sweden)

Andries J. Paarlberg

2015-07-01

Full Text Available Worldwide, significant dredging activities of riverbed sediment are employed to ensure that freight transportation on rivers can continue year-round. Imbalances of sediment budget may produce relevant impacts regarding river morphology and related environmental services. This study shows that hydro-morphodynamic modeling tools can be used to optimize dredge-and-dump activities and, at the same time, mitigate problems deriving from these activities in rivers. As a case study, we focused on dredging activities on the Lower Parana River, Argentina. Navigation on this river is of crucial importance to the economies of the bordering countries, hence, each year significant dredging activities are employed. To estimate dredging loads under different strategies, a 25 km river reach of the Parana River was modeled using the Delft3D-modelling suite by Deltares. The Netherlands, to simulate flow-sediment interactions in a quasi-steady and uncoupled approach. Impacts of dredging activities were explicitly included. Different dredge-and-dump strategies included variations in dredging over-depth (clearance and variations in dumping locations. Our results indicate that dredge-and-dump strategies can be targeted to stimulate natural processes that improve the depth and stability of the navigation channel and to counteract unwanted bed level responses in the long-medium term. A ~40% reduction in dredging effort could be achieved by moving the dredged material to distant locations in the secondary channel rather than dumping to the side of the waterway in the main channel.

Getting Lost Through Navigation

DEFF Research Database (Denmark)

Debus, Michael S.

2017-01-01

In this presentation, I argued two things. First, that it is navigation that lies at the core of contemporary (3D-) videogames and that its analysis is of utmost importance. Second, that this analysis needs a more rigorous differentiation between specific acts of navigation. Considering the Oxford...... in videogames is a configurational rather than an interpretational one (Eskelinen 2001). Especially in the case of game spaces, navigation appears to be of importance (Wolf 2009; Flynn 2008). Further, it does not only play a crucial role for the games themselves, but also for the experience of the player...

Inertial navigation without accelerometers

Science.gov (United States)

Boehm, M.

The Kennedy-Thorndike (1932) experiment points to the feasibility of fiber-optic inertial velocimeters, to which state-of-the-art technology could furnish substantial sensitivity and accuracy improvements. Velocimeters of this type would obviate the use of both gyros and accelerometers, and allow inertial navigation to be conducted together with vehicle attitude control, through the derivation of rotation rates from the ratios of the three possible velocimeter pairs. An inertial navigator and reference system based on this approach would probably have both fewer components and simpler algorithms, due to the obviation of the first level of integration in classic inertial navigators.

Domiciliary humidification improves lung mucociliary clearance in patients with bronchiectasis.

Science.gov (United States)

Hasani, A; Chapman, T H; McCool, D; Smith, R E; Dilworth, J P; Agnew, J E

2008-01-01

Inspired air humidification has been reported to show some benefit in bronchiectatic patients. We have investigated the possibility that one effect might be to enhance mucociliary clearance. Such enhancement might, if it occurs, help to lessen the risks of recurrent infective episodes. Using a radioaerosol technique, we measured lung mucociliary clearance before and after 7 days of domiciliary humidification. Patients inhaled high flow saturated air at 37 degrees C via a patient-operated humidification nasal inhalation system for 3 h per day. We assessed tracheobronchial mucociliary clearance from the retention of (99m)Tc-labelled polystyrene tracer particles monitored for 6 h, with a follow-up 24-h reading. Ten out of 14 initially recruited patients (age 37-75 years; seven females) completed the study (two withdrew after their initial screening and two prior to the initial clearance test). Seven patients studied were non-smokers; three were ex-smokers (1-9 pack-years). Initial tracer radioaerosol distribution was closely similar between pre- and post-treatment. Following humidification, lung mucociliary clearance significantly improved, the area under the tracheobronchial retention curve decreased from 319 +/- 50 to 271 +/- 46%h (p humidification treatment improved lung mucociliary clearance in our bronchiectatic patients. Given this finding plus increasing laboratory and clinical interest in humidification mechanisms and effects, we believe further clinical trials of humidification therapy are desirable, coupled with analysis of humidification effects on mucus properties and transport.

48 CFR 245.7101-4 - DD Form 1640, Request for Plant Clearance.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false DD Form 1640, Request for Plant Clearance. 245.7101-4 Section 245.7101-4 Federal Acquisition Regulations System DEFENSE... Forms 245.7101-4 DD Form 1640, Request for Plant Clearance. Use to request plant clearance assistance or...

Impairment of nasal mucociliary clearance in woodworkers in the furniture industry

Science.gov (United States)

Black, A.; Evans, J. C.; Hadfield, Esme H.; Macbeth, R. G.; Morgan, A.; Walsh, M.

1974-01-01

Black, A., Evans, J. C., Hadfield, Esme H., Macbeth, R. G., Morgan, A., and Walsh, M. (1974).British Journal of Industrial Medicine,31, 10-17. Impairment of nasal mucociliary clearance in woodworkers in the furniture industry. Measurements of mucociliary clearance from the anterior end of the middle turbinate were made using technetium-99m-labelled particles in nine woodworkers from the furniture industry and in 12 controls, none of whom had been occupationally exposed to wood dust. Clearance rates in the controls ranged from 1·9 to 18·5 mm min-1 with a mean of 6·8. These values are in good agreement with measurements reported elsewhere for normal subjects. Only one of the woodworkers had a clearance rate which fell within the normal range and he had been occupationally exposed for the shortest period (6 years). In four woodworkers clearance was very slow (furniture industry for more than 10 years. PMID:4821406

Renal clearance of 99mTc-methylene-diphosphonate in human beings

International Nuclear Information System (INIS)

Vattimo, A.

1987-01-01

The renal clearance of 99m Tc-MDP was measured in 13 patients who had bone scans and compared with the renal clearance of 51 Cr-EDTA. No difference was found between the renal clearance of the two tracers, showing a close correlation (r = 0.98). These data suggest that the 99m Tc-MDP is excreted by the kidneys by glomerular filtration without tubular secretion. (orig.) [de

Exercise increases the lung clearance of inhaled Tc-99m DTPA

International Nuclear Information System (INIS)

Meignan, M.; Rosso, J.; Cinotti, L.; Galle, P.

1985-01-01

It has been suggested that blood flow have little effect on the lung clearance of Tc-99m DTPA which depends on the alveolar distension. However an increase of pulmonary blood flow, induces a recruitment of new vascular areas which can enhance this clearance. To assess this hypothesis the pulmonary apical and basal clearances of a sumicronic aerosol of Tc-99m DTPA were studied at rest and at exercise in seven non smoking volunteers in upright posture. As a matter of fact exercising upright is known to increase primarily the apical blood flow. After inhalation the subjects were seated on a bicycle their back against a gamma camera which was linked to a computer. The lung radioactivity was registered successively during a resting and an exercising period. At rest there was a gradient of clearance from the apex to the base of the lung, the apical clearance being significantly higher. At exercise (50 Watts, 60 c. min /sup -1/, 7 min.) this regional gradient was enhanced by a large and significant increase of the apical clearances (0.0340 min /sup -1/ +-0.0063 SD versus 0.00183 min /sup -1/ +- 0.074 SD at rest, n = 7, p < 0.01). By contrast the changes of the basal clearances were slight and unsignificant (0.0146 min /sup -1/ +- 0.0062 SD versus 0.0140 min /sup -1/ +- 0.0082 SD). Since exercise induces little distension of the apical alveoli but drastically enhances the apical blood flow, the observed increase of the apical lung clearance could be primarily attributed to the recruitment of new capillaries induced by exercise in the apices. This led to an increase of the surface area permeability product

Oxygen Tension Beneath Scleral Lenses of Different Clearances.

Science.gov (United States)

Giasson, Claude J; Morency, Jeanne; Melillo, Marc; Michaud, Langis

2017-04-01

To evaluate the relative partial pressure in oxygen (pO2) at the corneal surface under Boston XO2 scleral lenses (SL) fitted with targeted clearances of 200 and 400 μm (SL200 and SL400). During this prospective study, the right eyes of eight normal subjects were fitted with SL200 and SL400. Clearance, validated after 5 minutes of wear with an optical coherence tomograph, was used with lens thicknesses to calculate transmissibility and estimate pO2. Corneal pO2s were measured with an oxygen electrode after 5 minutes of (1) corneal exposure to calibrating gases with various pO2 or of (2) SL wear. Decays in pO2 were modeled to an exponential. Linear regression between exponent k of these decays and calibrating gas pO2s allowed for the calculation of corneal pO2 under SL. Differences between pO2s beneath SL200 and SL400 were tested with a mixed ANOVA. The estimated transmissibility based on thicknesses and clearances (239.7 ± 34.7; 434.5 ± 33.2 μm) predicted a corneal pO2 of 8.52 ± 0.51 and 6.37 ± 0.28% for SL200 and SL400. These values were close to measured pO2: 9.07 ± 0.86 and 6.19 ± 0.87% (mean ± SEM) (P time, an 18-mm scleral lens fitted with a 400-μm clearance reduces the oxygen tension available to the cornea by 30% compared to a similar lens fitted with a 200-μm clearance after 5 minutes of wear.

Acute exposure to acid fog. Effects on mucociliary clearance

International Nuclear Information System (INIS)

Laube, B.L.; Bowes, S.M. III; Links, J.M.; Thomas, K.K.; Frank, R.

1993-01-01

Submicrometric sulfuric acid (H2SO4) aerosol can affect mucociliary clearance without eliciting irritative symptoms or changes in pulmonary function. The effect of larger fog droplets containing H2SO4 on mucociliary clearance is unknown. We quantified mucociliary clearance from the trachea (n = 4) and small airways (n = 7) of young healthy male adults after an acute exposure to H2SO4 fog (MMAD = 10.3 microns; pH = 2.0; liquid water content = 481 +/- 65 mg/m3; osmolarity = 30 mOsm). Acid fog (AF) or saline fog (SF) (10.9 microns; 492 +/- 116 mg/m3; 30 mOsm) was administered for 40 min of unencumbered breathing (no mouth-piece) at rest and for 20 min of exercise sufficient to produce oronasal breathing. Fog exposures were followed by a methacholine (MCh) challenge (a measure of airway reactivity) or inhalation of technetium-99M radioaerosol (MMAD = 3.4 microns) on 2 study days each. Changes in symptoms and forced ventilatory function were also assessed. Clearance was quantified from computer-assisted analyses of gamma camera images of the lower respiratory tract in terms of %removal/min of the radiolabel from the trachea 25 min after inhalation and from the outer zone of the right lung after 1.9 to 3 h. Symptoms, forced ventilatory function, and MCh response were unaffected by either fog. Tracheal clearance was more rapid in four of four subjects after AF (0.83 +/- 1.58% removal/min) compared with that after SF (-0.54 +/- 0.85% removal/min). Outer zone clearance was more rapid in six of seven subjects after AF (0.22 +/- 0.15% removal/min) compared with that after SF (0.01 +/- 0.09% removal/min)

20 CFR 655.150 - Interstate clearance of job order.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Interstate clearance of job order. 655.150... job order. (a) SWA posts in interstate clearance system. The SWA must promptly place the job order in... transmit a copy of its active job order to all States listed in the job order as anticipated worksites...

Dimerization of glycoprotein Ibα is not sufficient to induce platelet clearance.

Science.gov (United States)

Liang, X; Syed, A K; Russell, S R; Ware, J; Li, R

2016-02-01

ESSENTIALS: Many anti-glycoprotein (GP)Ibα antibodies induce platelet clearance in a dimer-dependent manner. Characterization of monoclonal antibodies that bind the mechanosensitive domain (MSD) of GPIbα. An anti-MSD antibody binds two copies of GPIbα in platelets but does not induce platelet clearance. The prevailing clustering model of GPIbα signaling is incorrect or needs revision. The mechanism of platelet clearance is not clear. Many antibodies binding the membrane-distal ligand-binding domain of glycoprotein (GP)Ibα induce rapid clearance of platelets and acute thrombocytopenia, which requires the bifurcated antibody structure. It was thought that binding of these antibodies induced lateral dimerization or clustering of GPIbα in the plasma membrane, which leads to downstream signaling and platelet clearance. However, many antibodies targeting GPIbβ and GPIX, which are associated with GPIbα in the GPIb-IX complex, do not induce platelet clearance, which is in contradiction to the clustering model. To test whether dimerization or clustering of GPIbα is sufficient to transmit the signal that leads to platelet clearance. We have recently raised several mAbs targeting the mechanosensitive domain (MSD) of GPIbα. Binding of these anti-MSD antibodies was characterized with biochemical methods. Their ability to stimulate platelets and induce platelet clearance in mice was assessed. Infusion of anti-MSD antibodies does not cause thrombocytopenia in mice. These antibodies show no detectable effects on platelet activation and aggregation in vitro. Further biochemical investigation showed that the anti-MSD antibody 3D1 binds two copies of GPIbα on the platelet surface. Therefore, lateral dimerization of GPIbα induced by antibody binding is not sufficient to initiate GPIb-IX signaling and induce platelet clearance. Our results suggest that a factor other than or in addition to clustering of GPIbα is required to induce platelet clearance. © 2015 International

HPT Clearance Control: Intelligent Engine Systems-Phase 1

Science.gov (United States)

2005-01-01

The following work has been completed to satisfy the Phase I Deliverables for the "HPT Clearance Control" project under NASA GRC's "Intelligent Engine Systems" program: (1) Need for the development of an advanced HPT ACC system has been very clearly laid out, (2) Several existing and potential clearance control systems have been reviewed, (3) A scorecard has been developed to document the system, performance (fuel burn, range, payload, etc.), thermal, and mechanical characteristics of the existing clearance control systems, (4) Engine size and flight cycle selection for the advanced HPT ACC system has been reviewed with "large engine"/"long range mission" combination showing the most benefit, (5) A scoring criteria has been developed to tie together performance parameters for an objective, data driven comparison of competing systems, and (6) The existing HPT ACC systems have been scored based on this scoring system.

78 FR 41304 - Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments; Correction

Science.gov (United States)

2013-07-10

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 105 [Docket No. USCG-2013-0397] RIN 1625-AC06 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments; Correction AGENCY: Coast Guard, DHS. ACTION: Final rule; correction. SUMMARY: The Coast Guard published a final rule...

32 CFR 154.16 - Security clearance.

Science.gov (United States)

2010-07-01

... part. The Director, Washington Headquarters Services (WHS) will initiate the required investigation... clearance, as appropriate. The Assistant Secretary of Defense (Legislative Affairs) will be notified by WHS...

Estimation of normal chromium-51 ethylene diamine tetra-acetic acid clearance in children

International Nuclear Information System (INIS)

Piepsz, A.; Pintelon, H.; Ham, H.R.

1994-01-01

In order to estimate the normal range of chromium-51 ethylene diamine tetra-acetic acid (EDTA) clearance in children, we selected a series of 256 patients with past or present urinary tract infection who showed, at the time of the clearance determination, normal technetium-99m dimercaptosuccinic acid (DMSA) scintigraphy and normal left to right DMSA relative uptake. The clearance was calculated by means of either the simplified second exponential method or the 120-min single blood sample; Chantler's correction was used in order to correct for having neglected the first exponential. There was a progressive increase in clearance from the first weeks of life (mean value around 1 month: 55 ml/min/1.73 m 2 ), with a plateau at around 18 months. Between 2 and 17 years of age, the clearance values remained constant, with a mean value of 114 ml/min/1.73 m 2 (SD: 24 ml/min); this is similar to the level described for inulin clearance. No significant differences were observed between boys and girls, or between clearance values calculated with one or with two blood samples. Taking into account the hour of intravenous injection of the tracer, we did not observe any influence of the lunchtime meal on the distribution of the 51 Cr-EDTA clearance values. (orig.)

Effect of prior immobilization on muscular glucose clearance in resting and running rats

International Nuclear Information System (INIS)

Vissing, J.; Ohkuwa, Tetsuo; Ploug, T.; Galbo, H.

1988-01-01

In vitro studies have shown that prior disuse impairs the glucose clearance of red skeletal muscle because of a developed insensitivity to insulin. We studied whether an impaired glucose clearance is present in vivo in 42-h immobilized muscles of resting rats and, furthermore, whether the exercise-induced increase in glucose clearance of red muscles is affected by prior immobilization. The 2-[ 3 H]deoxy-D-glucose (2DG) bolus injection method was used to determine glucose clearance of individual muscles. At rest, glucose clearance was markedly impaired in rats with previously immobilized red muscles compared with nonimmobilized control rats. During running, glucose clearance did not differ between muscles in previously immobilized and control rats. Insulin levels were always similar in the two groups and decreased during exercise. Intracellular nonphosphorylated 2DG was present in tissues with high glucose clearances. In conclusion, 42 h of immobilization markedly impairs glucose clearance of resting red muscle fibers in vivo. Apparently, physical inactivity in particular affects steps involved in insulin-mediated action that are not part of contraction-induced glucose uptake and metabolism. Presence of intracellular 2DG shows that separate determination of phosphorylated 2DG is necessary for accurate estimates of glucose metabolism and that accumulation of phosphorylated 2DG does not accurately reflect glucose transport

Analysis of foot clearance in firefighters during ascent and descent of stairs.

Science.gov (United States)

Kesler, Richard M; Horn, Gavin P; Rosengren, Karl S; Hsiao-Wecksler, Elizabeth T

2016-01-01

Slips, trips, and falls are a leading cause of injury to firefighters with many injuries occurring while traversing stairs, possibly exaggerated by acute fatigue from firefighting activities and/or asymmetric load carriage. This study examined the effects that fatigue, induced by simulated firefighting activities, and hose load carriage have on foot clearance while traversing stairs. Landing and passing foot clearances for each stair during ascent and descent of a short staircase were investigated. Clearances decreased significantly (p < 0.05) post-exercise for nine of 12 ascent parameters and increased for two of eight descent parameters. Load carriage resulted in significantly decreased (p < 0.05) clearance over three ascent parameters, and one increase during descent. Decreased clearances during ascent caused by fatigue or load carriage may result in an increased trip risk. Increased clearances during descent may suggest use of a compensation strategy to ensure stair clearance or an increased risk of over-stepping during descent. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Restricted Navigation Areas - USACE IENC

Data.gov (United States)

Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

Activation and clearance of vanadium alloys and beryllium multipliers in fusion reactors

International Nuclear Information System (INIS)

Bartenev, S.; Romanovskij, V.; Ciampichetti, A.; Zucchetti, M.; Forrest, R.; Kolbasov, B.; Romanov, P.

2006-01-01

Design of fusion reactors includes the development of low-activation materials. V-Cr-Ti alloys are among the candidate structural materials for the first wall and blanket, with the scarce and costly V as the main component. It is worth considering its regeneration and refabrication as well as to avoid its disposal as radioactive waste. However, to do so, it is necessary to bring its radioactivity down to sufficiently low levels. We have two possible goals: · Recycling (within the nuclear industry) for first wall and front blanket components. In that case, contact dose rate must be sufficiently low. · Clearance (release from nuclear regulatory control) for back blanket and backplate components. In that case, the clearance index must be below unity. In fact, for components less exposed to neutron activation, clearance may be reachable, after a conceivable period of decay. Maximum radionuclide concentrations in the alloys allowing their clearance were determined, using new IAEA Clearance Limits. For this purpose, also for less neutron-exposed structures, such as the back part of the blanket and the backplate, clearance is possible only if certain activation products are separated. As for recycling within the nuclear industry of first wall components, also for clearance it turns out that the development of isotope chemical separation techniques is interesting and necessary for our purposes. A suitable method for achieving the required substantial radioactivity reduction of activated V-Cr-Ti alloys is radiochemical extraction reprocessing, Such a technology, permitting to remove metallic activation products from spent materials, was developed and tested experimentally in Russia. Concerning clearance of less activated components, based on the estimated element distribution factors in the extraction and re-extraction processes, and computations, it was shown that the alloy components may be purified from the activation products, using this technology, down to an

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... NACFC Carolyn and C Richard Mattingly Leadership in Mental Health Care Award Mary M. Kontos Award NACFC Reflections ... help your infant or child manage their lung health, watch parents of children with CF and a respiratory therapist talk about the different techniques they use for airway clearance. ... Instagram Email Find a Clinical Trial Help us blaze ...

7 CFR 1927.53 - Costs of title clearance and closing of transactions.

Science.gov (United States)

2010-01-01

... 7 Agriculture 12 2010-01-01 2010-01-01 false Costs of title clearance and closing of transactions... and Loan Closing § 1927.53 Costs of title clearance and closing of transactions. The borrower or the... payment of all costs of title clearance and closing of the transaction and will arrange for payment before...

NFC Internal: An Indoor Navigation System

Science.gov (United States)

Ozdenizci, Busra; Coskun, Vedat; Ok, Kerem

2015-01-01

Indoor navigation systems have recently become a popular research field due to the lack of GPS signals indoors. Several indoors navigation systems have already been proposed in order to eliminate deficiencies; however each of them has several technical and usability limitations. In this study, we propose NFC Internal, a Near Field Communication (NFC)-based indoor navigation system, which enables users to navigate through a building or a complex by enabling a simple location update, simply by touching NFC tags those are spread around and orient users to the destination. In this paper, we initially present the system requirements, give the design details and study the viability of NFC Internal with a prototype application and a case study. Moreover, we evaluate the performance of the system and compare it with existing indoor navigation systems. It is seen that NFC Internal has considerable advantages and significant contributions to existing indoor navigation systems in terms of security and privacy, cost, performance, robustness, complexity, user preference and commercial availability. PMID:25825976

Experimental Investigation of Factors Influencing Operating Rotor Tip Clearance in Multistage Compressors

Directory of Open Access Journals (Sweden)

Reid A. Berdanier

2015-01-01

Full Text Available An analysis of compressor rotor tip clearance measurements using capacitance probe instrumentation is discussed for a three-stage axial compressor. Thermal variations and centrifugal effects related to rotational speed changes affect clearance heights relative to the assembled configuration. These two primary contributions to measured changes are discussed both independently and in combination. Emphasis is given to tip clearance changes due to changing loading condition and at several compressor operating speeds. Measurements show a tip clearance change approaching 0.1 mm (0.2% rotor span when comparing a near-choke operating condition to a near-stall operating condition for the third stage. Additional consideration is given to environmental contributions such as ambient temperature, for which changes in tip clearance height on the order of 0.05 mm (0.1% rotor span were noted for temperature variations of 15°C. Experimental compressor operating clearances are presented for several temperatures, operating speeds, and loading conditions, and comparisons are drawn between these measured variations and predicted changes under the same conditions.

USING TERRESTRIAL LASER SCANNERS TO CALCULATE AND MAP VERTICAL BRIDGE CLEARANCE

OpenAIRE

C. Zhang; D. Arditi; Z. Chen

2013-01-01

The vertical clearance of a bridge over a highway is important in preventing oversized vehicles from hitting the bridge. The vertical clearance of a bridge is traditionally measured by using surveying equipment such as leveling rods and total stations. Typically, measurements are taken at multiple locations in order to determine the minimum vertical clearance under the bridge. This process is time and labor consuming. Also, these measurements may not be accurate because of the traffi...

Brain-wide pathway for waste clearance captured by contrast-enhanced MRI

OpenAIRE

Iliff, Jeffrey J.; Lee, Hedok; Yu, Mei; Feng, Tian; Logan, Jean; Nedergaard, Maiken; Benveniste, Helene

2013-01-01

The glymphatic system is a recently defined brain-wide paravascular pathway for cerebrospinal fluid (CSF) and interstitial fluid (ISF) exchange that facilitates efficient clearance of solutes and waste from the brain. CSF enters the brain along para-arterial channels to exchange with ISF, which is in turn cleared from the brain along para-venous pathways. Because soluble amyloid β clearance depends on glymphatic pathway function, we proposed that failure of this clearance system contributes t...

75 FR 48564 - Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector...

Science.gov (United States)

2010-08-11

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Parts 3 and 165 [Docket No. USCG-2010-0351] RIN 1625-ZA25 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector Columbia River, WA AGENCY: Coast Guard, DHS. ACTION: Final rule. SUMMARY: This rule makes non-substantive...

Gamma-variate plasma clearance versus urinary plasma clearance of 51Cr-EDTA in patients with cirrhosis with and without fluid retention

DEFF Research Database (Denmark)

Fuglsang, Stefan; Henriksen, Ulrik L; Hansen, Hanne Boskov

2017-01-01

In patients with fluid retention, the plasma clearance of (51) Cr-EDTA (Clexp obtained by multiexponential fit) may overestimate the glomerular filtration rate (GFR). The present study was undertaken to compare a gamma-variate plasma clearance (Clgv) with the urinary plasma clearance of (51) Cr......-EDTA (Clu ) in patients with cirrhosis with and without fluid retention. A total of 81 patients with cirrhosis (22 without fluid retention, 59 with ascites) received a quantitative intravenous injection of (51) Cr-EDTA followed by plasma and quantitative urinary samples for 5 h. Clgv was determined from...... the injected dose relative to the plasma concentration-time area, obtained by a gamma-variate iterative fit. Clexp and Clu were determined by standard technique. In patients without fluid retention, Clgv , Clexp and Clu were closely similar. The difference between Clgv and Clu (Clgv - Clu = ΔCl) was mean -0...

Measurement of single kidney contrast media clearance by multiphasic spiral computed tomography: preliminary results

International Nuclear Information System (INIS)

Hackstein, N.; Puille, M.F.; Bak, Benjamin H.; Scharwat, Oliver; Rau, W.S.

2001-01-01

Objective. We present preliminary results of a new method (hereinafter called 'CT-clearance') to measure single kidney contrast media clearance by performing multiphasic helical CT of the kidneys. CT-clearance was calculated according to an extension of the Patlak-Plot. In contrast to prior investigators, who repeatedly measured a single slice, this method makes it possible to calculate single kidney clearance from at least three spiral CTs, utilizing the whole kidney volume. Methods. Spiral CT of the kidneys was performed unenhanced and about 30 and 100 s after administration of about 120 ml iopromide. Sum-density of the whole kidneys and aortic density was calculated from this data. Using this data, renal clearance of contrast media was calculated by CT-clearance in 29 patients. As reference, Serum-clearance was calculated in 24 patients by application of a modified one-exponential slope model. Information on the relative kidney function was gained by renal scintigraphy with Tc99m-MAG-3 or Tc99m-DMSA in 29 patients. Results. Linear regression analysis revealed a correlation coefficient of CT-clearance with Serum-clearance of r=0.78 with Cl (CT) [ml/min]=22.2+1.03 * Cl (serum), n=24. Linear regression of the relative kidney function (rkf) of the right kidney calculated by CT-clearance compared to scintigraphy results provided a correlation coefficient r=0.89 with rkf(CT)[%]=18.6+0.58 * rkf(scintigraphy), n=29. Conclusion. The obtained results of contrast media clearance measured by CT-clearance are in the physiological range of the parameter. Future studies should be performed to improve the methodology with the aim of higher accuracy. More specifically, better determination of the aortic density curve might improve the accuracy

Sex differences in navigation strategy and efficiency.

Science.gov (United States)

Boone, Alexander P; Gong, Xinyi; Hegarty, Mary

2018-05-22

Research on human navigation has indicated that males and females differ in self-reported navigation strategy as well as objective measures of navigation efficiency. In two experiments, we investigated sex differences in navigation strategy and efficiency using an objective measure of strategy, the dual-solution paradigm (DSP; Marchette, Bakker, & Shelton, 2011). Although navigation by shortcuts and learned routes were the primary strategies used in both experiments, as in previous research on the DSP, individuals also utilized route reversals and sometimes found the goal location as a result of wandering. Importantly, sex differences were found in measures of both route selection and navigation efficiency. In particular, males were more likely to take shortcuts and reached their goal location faster than females, while females were more likely to follow learned routes and wander. Self-report measures of strategy were only weakly correlated with objective measures of strategy, casting doubt on their usefulness. This research indicates that the sex difference in navigation efficiency is large, and only partially related to an individual's navigation strategy as measured by the dual-solution paradigm.

Celestial Navigation in the USA, Fiji, and Tunisia

Science.gov (United States)

Holbrook, Jarita C.

2015-05-01

Today there are many coastal communities that are home to navigators who use stars for position finding at night; I was, however, unaware of this fact when I began researching celestial navigation practices in 1997. My project focused on three communities: the Moce Islanders of Fiji, the Kerkennah Islanders in Tunisia, and the U.S. Navy officers and students at the United States Naval Academy, Annapolis, Maryland. My goal was to answer the question of why people continue to navigate by the stars, but also to understand the role of technology in their navigation practices. Using anthropology techniques of ethnography including participant observation, formal and informal interviews, audio and videotaping, I gathered data over five years at the three communities. I began by learning the details of how they use the stars for navigation. Next, I learned about who did the navigation and where they learned to navigate. I gathered opinions on various navigation aids and instruments, and opinions about the future of using the stars for navigation. I listened to the stories that they told about navigating. In the United States I worked in English, in Fiji, in Fijian and English, and in Tunisia, French and English. For the formal interviews I worked with translators. The navigators use stars for navigating today but the future of their techniques is not certain. Though practiced today, these celestial navigation traditions have undergone and continue to undergo changes. New navigational technologies are part of the stimulation for change, thus 'a meeting of different worlds' is symbolized by peoples encounters with these technologies.

Lung clearance of {sup 99m} Tc- DTPA in systemic lupus erythematous

Energy Technology Data Exchange (ETDEWEB)

Dalcin, P.T.R; Barreto, S.S.M.; Xavier, R.M.; Brenol, J.C.T. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Hospital de Clinicas. Dept. de Medicina Interna; Cunha, R.D.; Marroni, B.J. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Hospital de Clinicas. Servico de Medicina Nuclear]. E-mail: rxavier@hcpa.ufrgs.br

2002-06-01

The early demonstration of lung involvement in systemic lupus erythematosus (SLE) patients is a difficult but important task. In the present study we attempted to identify abnormalities in pulmonary clearance of 99 mTc-DTPA in SLE, correlating their clearance data with clinical findings and disease activity. Forty-six consecutive SLE patients with and without active disease (LACC score) and 30 normal volunteers were studied. All subjects were submitted to pulmonary scintigraphy with 99 mTc-DTPA to evaluate the pulmonary clearance, and to a chest X-ray, and SLE patients were submitted to tests of disease activity, spirometry, arterial blood gases and tests to assess acute-phase proteins. Pulmonary clearance was faster in SLE patients with active disease when compared to normal controls [half-life of 67.04 min (51.52-82.55 min) in active SLE versus 85.87 min (78.85-92.87 min) in controls, P<0.05] and there was a higher frequency of abnormal clearance rates in patients with active disease (11 of 26 patients, 42.3%) when compared with SLE patients without disease activity (2 of 20 patients, 10%) (P = 0.04). A significant correlation was observed between the clearance rates and cough (P<0.05), but not between the clearance rates and dyspnoea symptoms or radiological findings, duration of SLE disease, antinuclear antibody titers and patterns, C-reactive protein or anti-double stranded DNA antibodies. We conclude that the pulmonary clearance of 99 m Tc-DTPA is increased in SLE patients with active disease. (author)

Nautical Navigation Aids (NAVAID) Locations

Data.gov (United States)

Department of Homeland Security — Structures intended to assist a navigator to determine position or safe course, or to warn of dangers or obstructions to navigation. This dataset includes lights,...

Comparison of arterial intimal clearances of LDL from diabetic and nondiabetic cholesterol-fed rabbits. Differences in intimal clearance explained by size differences

International Nuclear Information System (INIS)

Nordestgaard, B.G.; Zilversmit, D.B.

1989-01-01

Arterial intimal clearances of low density lipoproteins (LDL) from diabetic cholesterol-fed rabbits (D-LDL) and LDL from nondiabetic cholesterol-fed rabbits (N-LDL) were compared. In six experiments, D-LDL and N-LDL were isolated from a diabetic and a nondiabetic rabbit, were iodinated with 125I and 131I, respectively, were mixed, and were reinjected into the same two rabbits as well as into a normal rabbit. Fractional catabolic rates for D-LDL and N-LDL in normal rabbits were 0.065 and 0.074 h-1 (p less than 0.05), respectively. For five of the six pairs of LDL, the D-LDL was smaller than N-LDL as determined by gel filtration. The arterial permeability to N-LDL, when normalized for differences in arterial cholesterol content, did not appear to differ between diabetic and nondiabetic rabbits. The relative arterial intimal clearance (D-LDL/N-LDL) in arteries from diabetic and nondiabetic rabbits was inversely related to the relative molecular weight (D-LDL/N-LDL). For example, when the molecular weight of D-LDL was as low as 60% of that of N-LDL (i.e., the diameter of D-LDL was reduced 16%), the intimal clearance of D-LDL was 40% larger than that of N-LDL. When, on the other hand, molecular weights and diameters of the two LDL were similar, the intimal clearance was also quite similar. These results suggest that arterial intimal clearance of LDL from diabetic and nondiabetic cholesterol-fed rabbits is comparable unless the two types of LDL have a different size

Clearance of the cervical spine in clinically unevaluable trauma patients.

Science.gov (United States)

Halpern, Casey H; Milby, Andrew H; Guo, Wensheng; Schuster, James M; Gracias, Vicente H; Stein, Sherman C

2010-08-15

Meta-analytic costeffectiveness analysis. Our goal was to compare the results of different management strategies for trauma patients in whom the cervical spine was not clinically evaluable due to impaired consciousness, endotracheal intubation, or painful distracting injuries. We performed a structured literature review related to cervical spine trauma, radiographic clearance techniques (plain radiography, flexion/extension, CT, and MRI), and complications associated with semirigid collar use. Meta-analytic techniques were used to pool data from multiple sources to calculate pooled mean estimates of sensitivities and specificities of imaging techniques for cervical spinal clearance, rates of complications from various clearance strategies and from empirical use of semirigid collars. A decision analysis model was used to compare outcomes and costs among these strategies. Slightly more than 7.5% of patients who are clinically unevaluable have cervical spine injuries, and 42% of these injuries are associated with spinal instability. Sensitivity of plain radiography or fluoroscopy for spinal clearance was 57% (95% CI: 57%-60%). Sensitivities for CT and MRI alone were 83% (82%-84%) and 87% (84%-89%), respectively. Complications associated with collar use ranged from 1.3% (2 days) to 7.1% (10 days) but were usually minor and short-lived. Quadriplegia resulting from spinal instability missed by a clearance test had enormous impacts on longevity, quality of life, and costs. These impacts overshadowed the effects of prolonged collar application, even when the incidence of quadriplegia was extremely low. As currently used, neuroimaging studies for cervical spinal clearance in clinically unevaluable patients are not cost-effective compared with empirical immobilization in a semirigid collar.

Clearance of slightly radioactive material from radiological control in Germany

International Nuclear Information System (INIS)

Thierfeldt, S.

1995-01-01

Clearance from radiological control of slightly radioactive material arising from operation or decommissioning of nuclear installations has been practiced in Germany for nearly two decades. Meanwhile, for the clearance of metal generally approved and applicable recommendations for clearance levels have been issued. For other materials like building waste, case-by-case decisions are made by the state licensing authorities. Efforts to implement consistent sets of clearance levels for all kinds of material are under way. As several decommissioning projects will soon generate large amounts of materials from dismantling, a solution needs to be reached soon. The legal framework in Germany governing the use of atomic energy consists of the Atomic Energy Act and several ordinances. Rules and guidelines including the recommendations of the German Commission for Radiation Protection (SSK) exist on a lower level and are not legally binding. Several generic studies for the derivation of clearance levels for metals and building debris with alpha, beta, and gamma contamination have been performed on behalf of the Federal Ministry for Environment, Nature Conservation and Nuclear Safety, which oriented themselves on an individual dose of 10 microSv/a in agreement with IAEA recommendations. Stochastic models have been used for establishing the connection between specific activity of the material to be released and the resulting individual doses, with significant advantages over deterministic scenarios. In the future, for new SSK recommendations or an ordinance on clearance, the increase of masses from demolition of installations, higher recycling rates in the conventional sector and harmonization with international regulations and standards have to be taken into account

Mucociliary clearance, airway inflammation and nasal symptoms in urban motorcyclists

Directory of Open Access Journals (Sweden)

Tereza C.S. Brant

2014-01-01

Full Text Available OBJECTIVES: There is evidence that outdoor workers exposed to high levels of air pollution exhibit airway inflammation and increased airway symptoms. We hypothesized that these workers would experience increased airway symptoms and decreased nasal mucociliary clearance associated with their exposure to air pollution. METHODS: In total, 25 non-smoking commercial motorcyclists, aged 18-44 years, were included in this study. These drivers work 8-12 hours per day, 5 days per week, driving on urban streets. Nasal mucociliary clearance was measured by the saccharine transit test; airway acidification was measured by assessing the pH of exhaled breath condensate; and airway symptoms were measured by the Sino-nasal Outcome Test-20 questionnaire. To assess personal air pollution exposure, the subjects used a passive-diffusion nitrogen dioxide (NO2 concentration-monitoring system during the 14 days before each assessment. The associations between NO2 and the airway outcomes were analyzed using the Mann-Whitney test and the Chi-Square test. Clinicaltrials.gov: NCT01976039. RESULTS: Compared with clearance in healthy adult males, mucociliary clearance was decreased in 32% of the motorcyclists. Additionally, 64% of the motorcyclists had airway acidification and 92% experienced airway symptoms. The median personal NO2 exposure level was 75 mg/m3 for these subjects and a significant association was observed between NO2 and impaired mucociliary clearance (p = 0.036. CONCLUSION: Non-smoking commercial motorcyclists exhibit increased airway symptoms and airway acidification as well as decreased nasal mucociliary clearance, all of which are significantly associated with the amount of exposure to air pollution.

Design of all-weather celestial navigation system

Science.gov (United States)

Sun, Hongchi; Mu, Rongjun; Du, Huajun; Wu, Peng

2018-03-01

In order to realize autonomous navigation in the atmosphere, an all-weather celestial navigation system is designed. The research of celestial navigation system include discrimination method of comentropy and the adaptive navigation algorithm based on the P value. The discrimination method of comentropy is studied to realize the independent switching of two celestial navigation modes, starlight and radio. Finally, an adaptive filtering algorithm based on P value is proposed, which can greatly improve the disturbance rejection capability of the system. The experimental results show that the accuracy of the three axis attitude is better than 10″, and it can work all weather. In perturbation environment, the position accuracy of the integrated navigation system can be increased 20% comparing with the traditional method. It basically meets the requirements of the all-weather celestial navigation system, and it has the ability of stability, reliability, high accuracy and strong anti-interference.

An on-line monitoring system for navigation equipment

Science.gov (United States)

Wang, Bo; Yang, Ping; Liu, Jing; Yang, Zhengbo; Liang, Fei

2017-10-01

Civil air navigation equipment is the most important infrastructure of Civil Aviation, which is closely related to flight safety. In addition to regular flight inspection, navigation equipment's patrol measuring, maintenance measuring, running measuring under special weather conditions are the important means of ensuring aviation flight safety. According to the safety maintenance requirements of Civil Aviation Air Traffic Control navigation equipment, this paper developed one on-line monitoring system with independent intellectual property rights for navigation equipment, the system breakthroughs the key technologies of measuring navigation equipment on-line including Instrument Landing System (ILS) and VHF Omni-directional Range (VOR), which also meets the requirements of navigation equipment ground measurement set by the ICAO DOC 8071, it provides technical means of the ground on-line measurement for navigation equipment, improves the safety of navigation equipment operation, and reduces the impact of measuring navigation equipment on airport operation.

32 CFR 644.3 - Navigation Projects.

Science.gov (United States)

2010-07-01

... 32 National Defense 4 2010-07-01 2010-07-01 true Navigation Projects. 644.3 Section 644.3 National... HANDBOOK Project Planning Civil Works § 644.3 Navigation Projects. (a) Land to be acquired in fee. All... construction and borrow areas. (3) In navigation-only projects, the right to permanently flood should be...

Clearance of building structures for conventional non-nuclear reuse

International Nuclear Information System (INIS)

Buss, K.; Boehringer, S.

1998-01-01

At the example of a fuel assembly plant the strategy of control measurements on building surfaces, which shall be conventionally reused after their clearance, is regarded. Based on the given clearance levels the used measuring methods, especially with regard of possibly covered or intruded uranium contamination, are shown. The possibility of using the in-situ-γ-spectroscopy is discussed. (orig.) [de

CO2 clearance by membrane lungs.

Science.gov (United States)

Sun, Liqun; Kaesler, Andreas; Fernando, Piyumindri; Thompson, Alex J; Toomasian, John M; Bartlett, Robert H

2018-05-01

Commercial membrane lungs are designed to transfer a specific amount of oxygen per unit of venous blood flow. Membrane lungs are much more efficient at removing CO 2 than adding oxygen, but the range of CO 2 transfer is rarely reported. Commercial membrane lungs were studied with the goal of evaluating CO 2 removal capacity. CO 2 removal was measured in 4 commercial membrane lungs under standardized conditions. CO 2 clearance can be greater than 4 times that of oxygen at a given blood flow when the gas to blood flow ratio is elevated to 4:1 or 8:1. The CO 2 clearance was less dependent on surface area and configuration than oxygen transfer. Any ECMO system can be used for selective CO 2 removal.

14 CFR 121.349 - Communication and navigation equipment for operations under VFR over routes not navigated by...

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Communication and navigation equipment for... § 121.349 Communication and navigation equipment for operations under VFR over routes not navigated by... receiver providing visual and aural signals; and (iii) One ILS receiver; and (3) Any RNAV system used to...

Quantum imaging for underwater arctic navigation

Science.gov (United States)

Lanzagorta, Marco

2017-05-01

The precise navigation of underwater vehicles is a difficult task due to the challenges imposed by the variable oceanic environment. It is particularly difficult if the underwater vehicle is trying to navigate under the Arctic ice shelf. Indeed, in this scenario traditional navigation devices such as GPS, compasses and gyrocompasses are unavailable or unreliable. In addition, the shape and thickness of the ice shelf is variable throughout the year. Current Arctic underwater navigation systems include sonar arrays to detect the proximity to the ice. However, these systems are undesirable in a wartime environment, as the sound gives away the position of the underwater vehicle. In this paper we briefly describe the theoretical design of a quantum imaging system that could allow the safe and stealthy navigation of underwater Arctic vehicles.

Autonomous Robot Navigation based on Visual Landmarks

DEFF Research Database (Denmark)

Livatino, Salvatore

2005-01-01

The use of landmarks for robot navigation is a popular alternative to having a geometrical model of the environment through which to navigate and monitor self-localization. If the landmarks are defined as special visual structures already in the environment then we have the possibility of fully a...... automatically learn and store visual landmarks, and later recognize these landmarks from arbitrary positions and thus estimate robot position and heading.......The use of landmarks for robot navigation is a popular alternative to having a geometrical model of the environment through which to navigate and monitor self-localization. If the landmarks are defined as special visual structures already in the environment then we have the possibility of fully...... autonomous navigation and self-localization using automatically selected landmarks. The thesis investigates autonomous robot navigation and proposes a new method which benefits from the potential of the visual sensor to provide accuracy and reliability to the navigation process while relying on naturally...

Dynamic analysis of cross shaft type universal joint with clearance

International Nuclear Information System (INIS)

Lu, Jian Wei; Wang, Gong Cheng; Chen, Hao; Vakakis, Alexander F.; Bergman, Lawrence A.

2013-01-01

Cross shaft type universal joint is widely used in ground vehicles to transfer torque between two intersecting axes, and its transmission feature can make a great contribution to NVH performance of the vehicle. We looked at the assembling clearance at cross shaft neck, and presented a dynamic model of cross shaft type universal joint with clearance at cross shaft neck. Two-state model is applied to describe the contact force between the cross shaft and driving joint fork based on Hertz theorem, and lumped mass method is applied to build up the dynamic model of the universal joint. Based on this model, numerical analysis is carried out to discuss the transmission feature of the universal joint with clearance at cross shaft neck, and the influence of clearance on the dynamic behavior of the system is evaluated with numerical results based on time history, power spectrum, and phase portrait. The method and conclusions presented are helpful to improvement of the transmission feature of cross shaft type universal joint.

NFC Internal: An Indoor Navigation System

Directory of Open Access Journals (Sweden)

Busra Ozdenizci

2015-03-01

Full Text Available Indoor navigation systems have recently become a popular research field due to the lack of GPS signals indoors. Several indoors navigation systems have already been proposed in order to eliminate deficiencies; however each of them has several technical and usability limitations. In this study, we propose NFC Internal, a Near Field Communication (NFC-based indoor navigation system, which enables users to navigate through a building or a complex by enabling a simple location update, simply by touching NFC tags those are spread around and orient users to the destination. In this paper, we initially present the system requirements, give the design details and study the viability of NFC Internal with a prototype application and a case study. Moreover, we evaluate the performance of the system and compare it with existing indoor navigation systems. It is seen that NFC Internal has considerable advantages and significant contributions to existing indoor navigation systems in terms of security and privacy, cost, performance, robustness, complexity, user preference and commercial availability.

Uncertainty analysis of 99mTc-HEPIDA liver clearance determination

International Nuclear Information System (INIS)

Surma, M. J.

2005-01-01

The aim of the study was to obtain information on the accuracy and precision of 99mT c-HEPIDA hepatic (Cl H p) and plasma (Cl P l) clearances and selection of an appropriate estimator of the measurement uncertainty of a single determination of these quantities. In a simulation (Monte Carlo) experiment, it was assumed that the recorded results of plasma and hepatic clearances, as obtained from 185 patients, provided authentic information about 99mT c-HEPIDA behaviour in the body over a wide range of the clearances studied. The time-course 99mT c-HEPIDA concentration in blood plasma has been described by means of biexponential function with parameter values derived for each patient. For each patient, using these data and urinary excretion data, there had been 5000 simulations performed; in each of the latter, the directly measured numbers have been substituted by simulated ones, obtained by means of varying the real ones, using random generated values. These reflected errors of plasma and radioactive standard pipetting (from 1 to 5%) and stochasticity of counting radioactive decay (1%). The time of blood sampling and urine voiding was also varied, assuming realistic uncertainty. The varied values were then used for computation of the simulated clearances. From the 5000 calculated clearances for each patient, mean-values were calculated, as well as mean standard errors, standard deviations and mean uncertainty of measurements using a widely accepted rule of partial error propagation, and, in addition, a modified rule of the latter. Accuracy of clearance (Cl P l, Cl H p, Cl U r) determination was assessed on the basis of comparison of mean values from simulations with those from directly recorded values. Precision was identified with standard deviation of each of the 5000 simulations. The uncertainty thus obtained was compared with results of calculated traditional and modified uncertainty. There was good agreement between standard deviation of the simulations with

Effect of prior immobilization on muscular glucose clearance in resting and running rats

DEFF Research Database (Denmark)

Vissing, J; Ohkuwa, T; Ploug, Thorkil

1988-01-01

with nonimmobilized control rats (red gastrocnemius 0.46 +/- 0.02 vs. 0.99 +/- 0.08 and soleus 1.10 +/- 0.30 vs. 3.97 +/- 0.54 ml.min-1.100 g-1, P less than 0.005). During running (18 m/min), glucose clearance did not differ between muscles in previously immobilized and control rats. Insulin levels were always......In vitro studies have shown that prior disuse impairs the glucose clearance of red skeletal muscle because of a developed insensitivity to insulin. We studied whether an impaired glucose clearance is present in vivo in 42-h immobilized muscles of resting rats and, furthermore, whether the exercise......-induced increase in glucose clearance of red muscles is affected by prior immobilization. The 2-[3H]deoxy-D-glucose (2DG) bolus injection method was used to determine glucose clearance of individual muscles. At rest, glucose clearance was markedly impaired in rats with previously immobilized red muscles compared...

Online feedback-controlled renal constant infusion clearances in rats.

Science.gov (United States)

Schock-Kusch, Daniel; Shulhevich, Yury; Xie, Qing; Hesser, Juergen; Stsepankou, Dzmitry; Neudecker, Sabine; Friedemann, Jochen; Koenig, Stefan; Heinrich, Ralf; Hoecklin, Friederike; Pill, Johannes; Gretz, Norbert

2012-08-01

Constant infusion clearance techniques using exogenous renal markers are considered the gold standard for assessing the glomerular filtration rate. Here we describe a constant infusion clearance method in rats allowing the real-time monitoring of steady-state conditions using an automated closed-loop approach based on the transcutaneous measurement of the renal marker FITC-sinistrin. In order to optimize parameters to reach steady-state conditions as fast as possible, a Matlab-based simulation tool was established. Based on this, a real-time feedback-regulated approach for constant infusion clearance monitoring was developed. This was validated by determining hourly FITC-sinistrin plasma concentrations and the glomerular filtration rate in healthy and unilaterally nephrectomized rats. The transcutaneously assessed FITC-sinistrin fluorescence signal was found to reflect the plasma concentration. Our method allows the precise determination of the onset of steady-state marker concentration. Moreover, the steady state can be monitored and controlled in real time for several hours. This procedure is simple to perform since no urine samples and only one blood sample are required. Thus, we developed a real-time feedback-based system for optimal regulation and monitoring of a constant infusion clearance technique.

Inland Electronic Navigational Charts (IENC)

Data.gov (United States)

Army Corps of Engineers, Department of the Army, Department of Defense — These Inland Electronic Navigational Charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

Exclusion, exemption, clearance European Union approach

International Nuclear Information System (INIS)

Janssens, A.

1997-01-01

The presentation overviews the following issues: Euratom Basic Safety Standards; administrative requirements; radiation protection of the population. Scope of the Standards: natural radiation sources; exclusion. Exemption; Clearance; Import of radioactive scrap metal

Low Cost Integrated Navigation System for Unmanned Vessel

Directory of Open Access Journals (Sweden)

Yang Changsong

2017-11-01

Full Text Available Large errors of low-cost MEMS inertial measurement unit (MIMU lead to huge navigation errors, even wrong navigation information. An integrated navigation system for unmanned vessel is proposed. It consists of a low-cost MIMU and Doppler velocity sonar (DVS. This paper presents an integrated navigation method, to improve the performance of navigation system. The integrated navigation system is tested using simulation and semi-physical simulation experiments, whose results show that attitude, velocity and position accuracy has improved awfully, giving exactly accurate navigation results. By means of the combination of low-cost MIMU and DVS, the proposed system is able to overcome fast drift problems of the low cost IMU.

A simple method for the verification of clearance levels for non-radioactive solid waste

International Nuclear Information System (INIS)

Holland, B.

1997-01-01

ANSTO's radiopharmaceutical production laboratories generate 25 m 3 of solid waste per month. Most of this waste is not radioactive. Up until recently the non-radioactive waste was cleared from the controlled area and stored for 10 halflives prior to disposal as normal solid refuse. To eliminate the storage and ''double handling'' of the large quantities of non-radioactive waste a simple clearance method was devised to allow direct disposal. This paper describes how clearance levels were determined. Here the term ''clearance level'' is used as a general term for the release of material regardless of whether it was previously subject to regulatory control. This contrasts with the IAEA definition of a clearance level and highlights a potential problem with the implementation of exemption levels to keep material out of regulatory control and the use of clearance levels to allow removal of materials from regulatory control. Several common hand held contamination monitors were tested to determine their limits of detection and ability to meet these clearance levels. The clearance method includes waste segregation and size limitation features to ensure the waste is monitored in a consistent manner, compatible with the limits of detection. The clearance levels achieved were subsequently found to be compatible with some of the unconditional clearance levels in IAEA-TECDOC-855 and the measurement method also meets the required features of that document. The ANSTO non-radioactive waste clearance system has been in operation for more than 12 months and has proved simple and effective to operate. Approximately 12m 3 of the solid waste is now been treated directly as normal solid refuse. This paper describes the ANSTO clearance system, the contamination monitor tests and details practical problems associated with the direct monitoring of solid waste, including averaging of the activity in the package. The paper also briefly highlights the potential problem with the use of

Impairment of paravascular clearance pathways in the aging brain.

Science.gov (United States)

Kress, Benjamin T; Iliff, Jeffrey J; Xia, Maosheng; Wang, Minghuan; Wei, Helen S; Zeppenfeld, Douglas; Xie, Lulu; Kang, Hongyi; Xu, Qiwu; Liew, Jason A; Plog, Benjamin A; Ding, Fengfei; Deane, Rashid; Nedergaard, Maiken

2014-12-01

In the brain, protein waste removal is partly performed by paravascular pathways that facilitate convective exchange of water and soluble contents between cerebrospinal fluid (CSF) and interstitial fluid (ISF). Several lines of evidence suggest that bulk flow drainage via the glymphatic system is driven by cerebrovascular pulsation, and is dependent on astroglial water channels that line paravascular CSF pathways. The objective of this study was to evaluate whether the efficiency of CSF-ISF exchange and interstitial solute clearance is impaired in the aging brain. CSF-ISF exchange was evaluated by in vivo and ex vivo fluorescence microscopy and interstitial solute clearance was evaluated by radiotracer clearance assays in young (2-3 months), middle-aged (10-12 months), and old (18-20 months) wild-type mice. The relationship between age-related changes in the expression of the astrocytic water channel aquaporin-4 (AQP4) and changes in glymphatic pathway function was evaluated by immunofluorescence. Advancing age was associated with a dramatic decline in the efficiency of exchange between the subarachnoid CSF and the brain parenchyma. Relative to the young, clearance of intraparenchymally injected amyloid-β was impaired by 40% in the old mice. A 27% reduction in the vessel wall pulsatility of intracortical arterioles and widespread loss of perivascular AQP4 polarization along the penetrating arteries accompanied the decline in CSF-ISF exchange. We propose that impaired glymphatic clearance contributes to cognitive decline among the elderly and may represent a novel therapeutic target for the treatment of neurodegenerative diseases associated with accumulation of misfolded protein aggregates. © 2014 American Neurological Association.

Intelligent personal navigator supported by knowledge-based systems for estimating dead reckoning navigation parameters

Science.gov (United States)

Moafipoor, Shahram

Personal navigators (PN) have been studied for about a decade in different fields and applications, such as safety and rescue operations, security and emergency services, and police and military applications. The common goal of all these applications is to provide precise and reliable position, velocity, and heading information of each individual in various environments. In the PN system developed in this dissertation, the underlying assumption is that the system does not require pre-existing infrastructure to enable pedestrian navigation. To facilitate this capability, a multisensor system concept, based on the Global Positioning System (GPS), inertial navigation, barometer, magnetometer, and a human pedometry model has been developed. An important aspect of this design is to use the human body as navigation sensor to facilitate Dead Reckoning (DR) navigation in GPS-challenged environments. The system is designed predominantly for outdoor environments, where occasional loss of GPS lock may happen; however, testing and performance demonstration have been extended to indoor environments. DR navigation is based on a relative-measurement approach, with the key idea of integrating the incremental motion information in the form of step direction (SD) and step length (SL) over time. The foundation of the intelligent navigation system concept proposed here rests in exploiting the human locomotion pattern, as well as change of locomotion in varying environments. In this context, the term intelligent navigation represents the transition from the conventional point-to-point DR to dynamic navigation using the knowledge about the mechanism of the moving person. This approach increasingly relies on integrating knowledge-based systems (KBS) and artificial intelligence (AI) methodologies, including artificial neural networks (ANN) and fuzzy logic (FL). In addition, a general framework of the quality control for the real-time validation of the DR processing is proposed, based on a

Nuclear security. DOE actions to improve the personnel clearance program

International Nuclear Information System (INIS)

Fultz, Keith O.; Bannerman, Carl J.; Daniel, Beverly A.

1988-11-01

The status of the Department of Energy's (DOE) implementation of recommendations in our two reports on DOE's personnel security clearance program was determined. The recommendations were aimed at improving the timeliness, accuracy, and efficiency of personnel security clearance decisions. Specifically, the objective was to determine and report on steps DOE is taking to implement these recommendations. In summary, it was found that DOE has either initiated action or is studying ways to address all the recommendations, but none of the recommendations have been completely implemented. The effectiveness of the DOE actions will depend, in part, on the adequacy of its internal control system for overseeing and evaluating program operations. DOE's personnel security clearance program is intended to provide reasonable assurance that personnel with access to classified information and materials are trustworthy. The Department requests that the Office of Personnel Management or the Federal Bureau of Investigation collect personal data on each person who requires such access to do his or her job. Based on these background investigations, DOE officials authorize individuals whose personal histories indicate that they are trustworthy to have access to classified information, secured facilities, and controlled materials as needed to perform their jobs. DOE has five types of these authorizations or personnel security clearances and must update information on personnel holding each type at 5-year intervals to confirm their continuing reliability. The five types are based on the types of security interests to which the person needs access, e.g., persons needing nuclear weapons-related data must have a Q clearance, and persons with a top secret clearance can have access to national security data classified as top secret

Hepatic macrophage complement receptor clearance function following injury.

Science.gov (United States)

Cuddy, B G; Loegering, D J; Blumenstock, F A; Shah, D M

1986-03-01

Previous work has demonstrated that in vivo hepatic macrophage complement receptor clearance function is depressed following thermal injury. The present study was carried out to determine if complement receptor function depression is associated with other states of depressed host defense. Hepatic complement receptor clearance function was determined from the hepatic uptake of rat erythrocytes coated with antierythrocyte IgM (EIgM) in rats. Receptor function was determined following cannulation of a carotid artery, laparotomy plus enterotomy, hemorrhagic shock, trauma, thermal injury, acute bacteremia, acute endotoxemia, and injection of erythrocyte stroma, gelatinized lipid emulsion, or colloidal carbon. Hepatic uptake of EIgM was depressed following each of these experimental interventions except arterial cannulation. This effect was shown not to be due to a decrease in hepatic blood flow or depletion of complement and was therefore due to a depression in hepatic macrophage complement receptor clearance function. Thus, impairment of hepatic macrophage complement receptor function is associated with several states of depressed host defense.

Clearance potential of ITER vacuum vessel activated materials

International Nuclear Information System (INIS)

Cepraga, D.G.; Cambi, G.; Frisoni, M.

2002-01-01

To demonstrate fusion's environmental attractiveness over the entire life cycle, a waste analysis is mandatory. The clearance is recommended by IAEA for releasing activated solid materials from regulatory control and for waste management policy. The paper focuses on the approach used to support waste analyses for ITER Generic Site Safety Report. The Material Unconditional Clearance Index of all the materials/zones on the equatorial mid-plane of ITER machine have been evaluated, based on IAEA-TECDOC-855. The Bonami-Nitawl-XSDNRPM sequence of the Scale-4.4a code system (using Vitenea-J library) has been firstly used for radiation transport analyses. Then the Anita-2000 code package is used for the activation calculation. The paper presents also, as an example, an application of the clearance indexes estimation for the ITER vacuum vessel materials. The results of the Anita-2000 have been compared with those obtained using the Fispact-99 activation code. (author)

Contrast media and glomerular filtration: dose dependence of clearance for three agents

International Nuclear Information System (INIS)

Baeck, S.E.K.; Krutzen, E.; Nilsson-Ehle, P.

1988-01-01

Determination of plasma clearance of contrast agents has been advocated as a means to assess glomerular filtration rate. To evaluate the feasibility of different agents for this purpose, we have compared, in healthy volunteers, the dose dependence of plasma clearance for three contrast media (iohexol, a nonionic agent, and iothalamate and metrizoate, which are ionic substances), with special emphasis on the lower dose range (2-20 mL corresponding to 0.9-12.9 g, depending on dose and agent). Iohexol and iothalamate were cleared at constant rates, irrespective of given dose, whereas metrizoate clearance increased significantly at lower doses. In general, the clearances or iothalamate and metrizoate were, respectively, moderately and markedly higher than that of iohexol. The clearance of different doses of metrizoate (2 mL versus a radiographic dose of 40 mL or more) was also compared with the clearance of [ 51 Cr]EDTA in two groups of patients with reduced renal function. When compared with [ 51 Cr]EDTA in patients with renal dysfunction, metrizoate was cleared significantly faster after a 2-mL dose, whereas clearances were identical when the metrizoate dose was 40 mL or more. These findings indicate that tubular secretion plays an active role in the elimination of metrizoate. The pharmacokinetic properties of iohexol, in combination with its low toxicity, make it a suitable agent for determination of glomerular filtration rate in clinical practice

Clearance from the anterior chamber of RBCs from human diabetics

International Nuclear Information System (INIS)

Williams, G.A.; Hatchell, D.L.; Collier, B.D.; Knobel, J.

1984-01-01

Erythrocytes from diabetic patients manifest decreased deformability and increased adherence. These abnormal membrane properties may diminish the ability of erythrocytes (RBCs) from diabetics to undergo deformation in passage through the trabecular meshwork. Using sodium chromate Cr 51-labeled RBCs from type I diabetic patients with proliferative retinopathy and normal control subjects, we studied RBC clearance from the rabbit anterior chamber. The mean time for 50% clearance (T50) of RBCs from diabetics (76 hours) was significantly longer than that for RBCs from normal subjects (19.5 hours). In this model, RBCs from diabetics have a slower clearance from the anterior chamber than do RBCs from normal subjects

Development of field navigation system; Field navigation system no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Ibara, S; Minode, M; Nishioka, K [Daihatsu Motor Co. Ltd., Osaka (Japan)

1995-04-20

This paper describes the following matters on a field navigation system developed for the purpose of covering a field of several kilometer square. This system consists of a center system and a vehicle system, and the center system comprises a map information computer and a communication data controlling computer; since the accuracy for a vehicle position detected by a GPS is not sufficient, an attempt of increasing the accuracy of vehicle position detection is made by means of a hybrid system; the hybrid system uses a satellite navigation method of differential system in which the error components in the GPS are transmitted from the center, and also uses a self-contained navigation method which performs an auxiliary function when the accuracy in the GPS has dropped; corrected GPS values, emergency messages to all of the vehicles and data of each vehicle position are communicated by wireless transmission in two ways between the center and vehicles; and accommodation of the map data adopted a system that can respond quickly to any change in roads and facilities. 3 refs., 13 figs., 1 tab.

Experimental Study of Unshrouded Impeller Pump Stage Sensitivity to Tip Clearance

Science.gov (United States)

Williams, Robert W.; Zoladz, Thomas; Storey, Anne K.; Skelley, Stephen E.

2002-01-01

This viewgraph presentation provides information on an experiment. Its objective is to experimentally determine unshrouded impeller performance sensitivity to tip clearance. The experiment included: Determining impeller efficiency at scaled operating conditions in water at MSFC's Pump Test Equipment (PTE) Facility; Testing unshrouded impeller at three different tip clearances; Testing each tip clearance configuration at on- and off-design conditions, and collecting unsteady- and steady-state data in each configuration; Determining impeller efficiency directly using drive line torquemeter and pump inlet and exit total pressure measurements.

Compact autonomous navigation system (CANS)

Science.gov (United States)

Hao, Y. C.; Ying, L.; Xiong, K.; Cheng, H. Y.; Qiao, G. D.

2017-11-01

Autonomous navigation of Satellite and constellation has series of benefits, such as to reduce operation cost and ground station workload, to avoid the event of crises of war and natural disaster, to increase spacecraft autonomy, and so on. Autonomous navigation satellite is independent of ground station support. Many systems are developed for autonomous navigation of satellite in the past 20 years. Along them American MANS (Microcosm Autonomous Navigation System) [1] of Microcosm Inc. and ERADS [2] [3] (Earth Reference Attitude Determination System) of Honeywell Inc. are well known. The systems anticipate a series of good features of autonomous navigation and aim low cost, integrated structure, low power consumption and compact layout. The ERADS is an integrated small 3-axis attitude sensor system with low cost and small volume. It has the Earth center measurement accuracy higher than the common IR sensor because the detected ultraviolet radiation zone of the atmosphere has a brightness gradient larger than that of the IR zone. But the ERADS is still a complex system because it has to eliminate many problems such as making of the sapphire sphere lens, birefringence effect of sapphire, high precision image transfer optical fiber flattener, ultraviolet intensifier noise, and so on. The marginal sphere FOV of the sphere lens of the ERADS is used to star imaging that may be bring some disadvantages., i.e. , the image energy and attitude measurements accuracy may be reduced due to the tilt image acceptance end of the fiber flattener in the FOV. Besides Japan, Germany and Russia developed visible earth sensor for GEO [4] [5]. Do we have a way to develop a cheaper/easier and more accurate autonomous navigation system that can be used to all LEO spacecraft, especially, to LEO small and micro satellites? To return this problem we provide a new type of the system—CANS (Compact Autonomous Navigation System) [6].

Scan Manifestations and Blood Clearance Rates in Typhoid Liver

International Nuclear Information System (INIS)

Bahk, Yong Whee; Ahn, Jae Sung; Kim, Soon Hi

1970-01-01

Fourteen patients with typhoid fever studied by scanning and clearance-rate measurements of subcritical dose colloidal radiogold ( 198 Au). Mild to moderate enlargement of the liver and spleen was noted in 78.6 and 64.3 percent of patients, respectively; and splenic and spinal bone-marrow uptake was seen in 78.6 and 57.1 percent of cases, respectively. Typically, these scan changes occurred concomitantly (57.1%) and are considered to represent increased phagocytic activity of the RE cells which is characteristic of typhoid fever. The half clearance-time was significantly shortened during the first 10-day period of the illness indicating an increase in the hepatic blood in the early phase of typhoid infection. Hepatomegaly, splenomegaly and extrahepatic uptakes along with an accelerated (or less a normal) clearance time are characteristic of typhoid fever.

Exaggerated natriuresis and lithium clearance in spontaneously hypertensive rats

DEFF Research Database (Denmark)

Holstein-Rathlou, N H; Kanters, J K; Leyssac, P P

1988-01-01

Since hypertension is associated with changes in the handling of various cations (including sodium and lithium) across the cell membrane, the present study investigated the validity of the lithium clearance method in hypertension by comparing two measures of proximal reabsorption. Thus, fractional...... lithium excretion and transit time (TT)-occlusion time (OT; e-TT/T) were determined successively in the same spontaneously hypertensive rat (SHR, Okamoto strain). The rats were examined both before and after an acute saline load. The results show that the lithium clearance method can be used...... for the determination of proximal reabsorption in SHR. Utilizing the lithium clearance method, the changes in renal sodium handling underlying the exaggerated natriuresis were investigated in unanaesthetized catheterized rats. It was found that the exaggerated natriuresis was associated with an increased output from...

Kinematics Simulation Analysis of Packaging Robot with Joint Clearance

Science.gov (United States)

Zhang, Y. W.; Meng, W. J.; Wang, L. Q.; Cui, G. H.

2018-03-01

Considering the influence of joint clearance on the motion error, repeated positioning accuracy and overall position of the machine, this paper presents simulation analysis of a packaging robot — 2 degrees of freedom(DOF) planar parallel robot based on the characteristics of high precision and fast speed of packaging equipment. The motion constraint equation of the mechanism is established, and the analysis and simulation of the motion error are carried out in the case of turning the revolute clearance. The simulation results show that the size of the joint clearance will affect the movement accuracy and packaging efficiency of the packaging robot. The analysis provides a reference point of view for the packaging equipment design and selection criteria and has a great significance on the packaging industry automation.

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... working for a cure, the CF Foundation supports programs and policies to improve the lives of people with CF. Help us by raising awareness of CF, participating in a fundraising ... DONATE Breadcrumb Navigation Home ...

Numerical study on tip clearance effect on performance of a centrifugal compressor

International Nuclear Information System (INIS)

Eum, Hark Jin; Kang, Shin Kyoung

2003-01-01

Effect of tip leakage flow on through flow and performance of a centrifugal compressor impeller was numerically studied using CFX-TASCflow. Seven different tip clearances were used to consider the influence of tip clearance on performance. Secondary flow and loss factor were evaluated to understand the loss mechanism inside the impeller due to tip leakage flow. The calculated results were circumferentially averaged along the passage and at the impeller exit for quantitative discussion. Tip clearance effect on performance could be decomposed into inviscid and viscous components using one dimensional equation. The inviscid component is related with the specific work reduction and the viscous component is related with the additional entropy generation. Two components affected performance equally, while efficiency drop was mainly influenced by viscous loss. Performance and efficiency drop due to tip clearance were proportional to the ratio of tip clearance to exit blade height. A simple model suggested in the present study predict performance and efficiency drop quite successfully

Plasma Creatinine Clearance in the Dog

Science.gov (United States)

Frazier, Loy W.

1977-01-01

Lists materials and methods for an experiment that demonstrates the concept of glomerular filtration rate (GFR) using anesthesized dogs. In the dog, GFR is equivalent to the renal plasma clearance of exogenous creatinine. (CS)

Parsimonious Ways to Use Vision for Navigation

Directory of Open Access Journals (Sweden)

Paul Graham

2012-05-01

Full Text Available The use of visual information for navigation appears to be a universal strategy for sighted animals, amongst which, one particular group of expert navigators are the ants. The broad interest in studies of ant navigation is in part due to their small brains, thus biomimetic engineers expect to be impressed by elegant control solutions, and psychologists might hope for a description of the minimal cognitive requirements for complex spatial behaviours. In this spirit, we have been taking an interdisciplinary approach to the visual guided navigation of ants in their natural habitat. Behavioural experiments and natural image statistics show that visual navigation need not depend on the remembering or recognition of objects. Further modelling work suggests how simple behavioural routines might enable navigation using familiarity detection rather than explicit recall, and we present a proof of concept that visual navigation using familiarity can be achieved without specifying when or what to learn, nor separating routes into sequences of waypoints. We suggest that our current model represents the only detailed and complete model of insect route guidance to date. What's more, we believe the suggested mechanisms represent useful parsimonious hypotheses for the visually guided navigation in larger-brain animals.

Risk management model of winter navigation operations

International Nuclear Information System (INIS)

Valdez Banda, Osiris A.; Goerlandt, Floris; Kuzmin, Vladimir; Kujala, Pentti; Montewka, Jakub

2016-01-01

The wintertime maritime traffic operations in the Gulf of Finland are managed through the Finnish–Swedish Winter Navigation System. This establishes the requirements and limitations for the vessels navigating when ice covers this area. During winter navigation in the Gulf of Finland, the largest risk stems from accidental ship collisions which may also trigger oil spills. In this article, a model for managing the risk of winter navigation operations is presented. The model analyses the probability of oil spills derived from collisions involving oil tanker vessels and other vessel types. The model structure is based on the steps provided in the Formal Safety Assessment (FSA) by the International Maritime Organization (IMO) and adapted into a Bayesian Network model. The results indicate that ship independent navigation and convoys are the operations with higher probability of oil spills. Minor spills are most probable, while major oil spills found very unlikely but possible. - Highlights: •A model to assess and manage the risk of winter navigation operations is proposed. •The risks of oil spills in winter navigation in the Gulf of Finland are analysed. •The model assesses and prioritizes actions to control the risk of the operations. •The model suggests navigational training as the most efficient risk control option.

Renal clearance of /sup 99m/Tc-methylene-diphosphonate in human beings

Energy Technology Data Exchange (ETDEWEB)

Vattimo, A.

1987-12-01

The renal clearance of /sup 99m/Tc-MDP was measured in 13 patients who had bone scans and compared with the renal clearance of /sup 51/Cr-EDTA. No difference was found between the renal clearance of the two tracers, showing a close correlation (r = 0.98). These data suggest that the /sup 99m/Tc-MDP is excreted by the kidneys by glomerular filtration without tubular secretion.

Frequency and factors effecting non clearance of lower pole renal stones

International Nuclear Information System (INIS)

Ullah, A.; Zubair, M.; Khan, N.; Malik, A.

2015-01-01

Renal stone disease is a major health hazard in Pakistan and extra-corporeal shockwave lithotripsy is one of comprehensive method used to treat these stones. The aim of this study is to determine the frequency of factors affecting the non-clearance of stone fragments of lower pole renal stone after extra corporeal shockwave lithotripsy. The study was done with the objective to determine the frequency the spatial anatomical factors which can influence the non-clearance of lower pole stone fragments after ESWL. Methods: One and nineteen (119) patients with lower pole renal stone less than 10 mm were subjected to maximum 3 sessions of extracorporeal shock wave lithotripsy. KUB radiographs, ultrasonography and intravenous urography were used as investigative tools for lower pole renal calyceal anatomy. X ray KUB and ultrasound were done after a week for clearance. Data was analysed with the help of SPSS version 10.0 and presented in the forms of tables and graphs. Results: There were 77 (64.71%) males and 42 (35.29%) females. Infundibulo-pelvic angle (IPA)>40 degree was present in 93 (78.15%), Infundibular length (IL) <22 mm in 107 (89.92%) and Infundibular width (IW) >4 mm was present in 100 (84.03%) patients. The frequency of stone non clearance was noted in 31 (26.05%). Infundibulo-pelvic angle (IPA)>40 degree (p=0.000), Infundibular length (IL)<22 mm (p=0.001) and Infundibular width (IW)>4 mm (p=0.046) were significant variables affecting stone clearance. Conclusion: The frequency of non-clearance of lower calyx of kidney stone is 26.05%. The clearance of fragments of the lower calyx kidney stones is affected by three spatial anatomical factors, i.e., Infundibulopelvic angle, Infundibular width and infundibular length. (author)

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... today. ANNUAL FUND Become a Corporate Supporter Cause Marketing Make a Charitable Gift Our Corporate Supporters Workplace ... Leaders About Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... today. ANNUAL FUND Become a Corporate Supporter Cause Marketing Make a Charitable Gift Our Corporate Supporters Workplace ... Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With CF Treatments ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With CF Treatments ... can do on their own. Share Facebook Twitter Email More options Print Share Facebook Twitter Email Print ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... today. ANNUAL FUND Become a Corporate Supporter Cause Marketing Make a Charitable Gift Our Corporate Supporters Workplace ... About Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With CF ...

Delayed clearance of serum HBsAg in compensated cirrhosis B

DEFF Research Database (Denmark)

Fattovich, G; Giustina, G; Sanchez-Tapias, J

1998-01-01

The aim of this study was to evaluate the incidence, prognostic factors and clinical significance of delayed clearance of serum HBsAg in compensated cirrhosis B.......The aim of this study was to evaluate the incidence, prognostic factors and clinical significance of delayed clearance of serum HBsAg in compensated cirrhosis B....

Turbulent Heat Transfer of a Finned Plate in a Duct as Tip Clearance Changes

Energy Technology Data Exchange (ETDEWEB)

Park, Hae-Kyun; Chung, Bum-Jin [Kyung Hee University, Yongin (Korea, Republic of)

2015-05-15

Fins are employed to enhance the cooling performance of a system. There are a number of studies relevant to geometry of fins. Meanwhile, the studies relevant to tip clearance, have not performed enough, which is the distance between the tips of the fins and the wall. We investigated the optimal tip clearance, which maximizes the heat transfers by experimental and numerical analyses with wider range of Re{sub Dh} than the previous studies. Turbulent heat transfers of a finned plate were measured. For an extended range of tip clearance and Re{sub Dh} than other studies. A joint experimental and numerical analyses was performed to measure heat transfers. Mass transfer experiments using electroplating system was used and FLUENT 6.3.26 was used for the calculation. For the narrow tip clearances below 5 mm, were investigated by numerical method only. The bypass flow to the tip clearance region contributes to heat transfer area at the tip clearance region and does not contributes that of the fin region. Thus, the optimal tip clearance was founded and it exists vicinity of 0.2 mm.

Novel sensors to enable closed-loop active clearance control in gas turbine engines

Science.gov (United States)

Geisheimer, Jonathan; Holst, Tom

2014-06-01

Active clearance control within the turbine section of gas turbine engines presents and opportunity within aerospace and industrial applications to improve operating efficiencies and the life of downstream components. Open loop clearance control is currently employed during the development of all new large core aerospace engines; however, the ability to measure the gap between the blades and the case and close down the clearance further presents as opportunity to gain even greater efficiencies. The turbine area is one of the harshest environments for long term placement of a sensor in addition to the extreme accuracy requirements required to enable closed loop clearance control. This paper gives an overview of the challenges of clearance measurements within the turbine as well as discusses the latest developments of a microwave sensor designed for this application.

Does sleep disturbance affect the amyloid clearance mechanisms in Alzheimer's disease?

Science.gov (United States)

Yulug, Burak; Hanoglu, Lutfu; Kilic, Ertugrul

2017-10-01

Sleep is an important factor that plays a key role in Alzheimer's disease pathogenesis. However, it is still unclear whether poor-quality sleep may overlap with sleep disturbances in the underlying dysfunctional mechanisms of amyloid beta (Aβ) clearance metabolism. Here, we aimed to evaluate the current evidence on the role of sleep deprivation in Aβ clearance metabolism. To that end, we discuss possible mechanisms underlying the bidirectional interaction between the sleep deprivation and Aβ clearance pathways. © 2017 The Authors. Psychiatry and Clinical Neurosciences © 2017 Japanese Society of Psychiatry and Neurology.

Adaptive Landmark-Based Navigation System Using Learning Techniques

DEFF Research Database (Denmark)

Zeidan, Bassel; Dasgupta, Sakyasingha; Wörgötter, Florentin

2014-01-01

The goal-directed navigational ability of animals is an essential prerequisite for them to survive. They can learn to navigate to a distal goal in a complex environment. During this long-distance navigation, they exploit environmental features, like landmarks, to guide them towards their goal. In...... hexapod robots. As a result, it allows the robots to successfully learn to navigate to distal goals in complex environments.......The goal-directed navigational ability of animals is an essential prerequisite for them to survive. They can learn to navigate to a distal goal in a complex environment. During this long-distance navigation, they exploit environmental features, like landmarks, to guide them towards their goal....... Inspired by this, we develop an adaptive landmark-based navigation system based on sequential reinforcement learning. In addition, correlation-based learning is also integrated into the system to improve learning performance. The proposed system has been applied to simulated simple wheeled and more complex...

A navigational evaluation model for content management systems

International Nuclear Information System (INIS)

Gilani, S.; Majeed, A.

2016-01-01

Web applications are widely used world-wide, however it is important that the navigation of these websites is effective, to enhance usability. Navigation is not limited to links between pages, it is also how we complete a task. Navigational structure presented as hypertext is one of the most important component of the Web application besides content and presentation. The main objective of this paper is to explore the navigational structure of various open source Content Management Systems from the developer's perspective. For this purpose three CMS are chosen which are WordPress, Joomla, and Drupal. Objective of the research is to identify the important navigational aspects present in these CMSs. Moreover, a comparative study of these CMSs in terms of navigational support is required. For this purpose an industrial survey is conducted based on our proposed navigational evaluation model. The results shows that there exist correlation between the identified factors and these CMSs provide helpful and effective navigational support to their users. (author)

76 FR 59379 - Proposed Information Collection; Comment Request; Generic Clearance for Research in Development...

Science.gov (United States)

2011-09-26

...-XXXX. Type of Review: Generic Clearance Request. Title: Generic Clearance for Research in Development... information collected through qualitative evaluation methods will inform the disclosure form's design and... Proposed Information Collection; Comment Request; Generic Clearance for Research in Development of...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Leaders About Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With ... Oscillation (the Vest) Follow Us On Facebook Twitter YouTube Instagram Email Find a Clinical Trial Help us ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... AWARENESS Tomorrow’s Leaders About Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home ... that they can do on their own. Share Facebook Twitter Email More options Print Share Facebook Twitter ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... About Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With CF ... the Vest) Follow Us On Facebook Twitter YouTube Instagram Email Find a Clinical Trial Help us blaze ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Reform Could Impact People With CF The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements ... AWARENESS Tomorrow’s Leaders About Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Clinician Career Development Awards Clinician Training Awards Mutation Analysis Program Network News Network News: June 2018 Network ... Tomorrow’s Leaders About Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life ...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Tomorrow’s Leaders About Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life ... they can do on their own. Share Facebook Twitter Email More options Print Share Facebook Twitter Email ...

A comparison of analytic procedures for measurement of fractional dextran clearances

NARCIS (Netherlands)

Hemmelder, MH; de Jong, PE; de Zeeuw, D

Fractional dextran clearances have been extensively used to study glomerular size selectivity. We report on an analysis of different laboratory procedures involved in measuring fractional dextran clearances. The deproteinization of plasma samples by 20% trichloroacetic acid (TCA) revealed a protein

Interactive navigation-guided ophthalmic plastic surgery: navigation enabling of telescopes and their use in endoscopic lacrimal surgeries

Directory of Open Access Journals (Sweden)

Ali MJ

2016-11-01

Full Text Available Mohammad Javed Ali,1 Swati Singh,1 Milind N Naik,1 Swathi Kaliki,2 Tarjani Vivek Dave1 1The Institute of Dacryology, 2The Operation Eyesight Universal Institute for Eye Cancer, L.V. Prasad Eye Institute, Hyderabad, India Purpose: The aims of this study were to report the preliminary experience of using telescopes, which were enabled for navigation guidance, and their utility in complex endoscopic lacrimal surgeries. Methods: Navigation enabling of the telescope was achieved by using the AxiEM™ malleable neuronavigation shunt stylet. Image-guided dacryolocalization was performed in five patients using the intraoperative image-guided StealthStation™ system in the electromagnetic mode. The “look ahead” protocol software was used to assist the surgeon in assessing the intraoperative geometric location of the endoscope and what lies ahead in real time. All patients underwent navigation-guided powered endoscopic dacryocystorhinostomy. The utility of uninterrupted navigation guidance throughout the surgery with the endoscope as the navigating tool was noted. Results: Intraoperative geometric localization of the lacrimal sac and the nasolacrimal duct could be easily deciphered. Constant orientation of the lacrimal drainage system and the peri-lacrimal anatomy was possible without the need for repeated point localizations throughout the surgery. The “look ahead” features could accurately alert the surgeon of anatomical structures that exists at 5, 10 and 15 mm in front of the endoscope. Good securing of the shunt stylet with the telescope was found to be essential for constant and accurate navigation. Conclusion: Navigation-enabled endoscopes provide the surgeon with the advantage of sustained stereotactic anatomical awareness at all times during the surgery. Keywords: telescope, endoscope, image guidance, navigation, lacrimal surgery, powered endoscopic DCR

Vibrotactile in-vehicle navigation system

NARCIS (Netherlands)

Erp, J.B.F. van; Veen, H.J. van

2004-01-01

A vibrotactile display, consisting ofeight vibrating elements or tactors mounted in a driver's seat, was tested in a driving simulator. Participants drove with visual, tactile and multimodal navigation displays through a built-up area. Workload and the reaction time to navigation messages were

Spontaneous Clearance of Hepatitis C after Liver and Renal Transplantation

Directory of Open Access Journals (Sweden)

CH Dale

2009-01-01

Full Text Available Spontaneous clearance of hepatitis C virus (HCV is rare in immunocompromised patients, such as those who have undergone organ transplantation. It has been recognized that patients receiving liver transplantation for HCV-related disease have decreased graft and patient survival compared with those transplanted for other etiologies. There is a growing trend toward treating HCV recurrence aggressively after liver transplantation. For other organ transplant recipients with concurrent HCV, treatment is not often an option, given the high rates of graft rejection and loss secondary to interferon and its immunomodulatory effects. Although spontaneous clearance of HCV has been reported in recipients of solitary liver and renal transplants, a common factor arising in these cases has been previous exposure to interferon. To date, no reports of spontaneous clearance of HCV RNA have been reported in a multiorgan transplant recipient. A case of spontaneous clearance of HCV RNA in an immunocompromised patient, within five months of simultaneous liver and kidney retransplantation is described. Importantly, this patient had no previous exposure to interferon.

The attack navigator

DEFF Research Database (Denmark)

Probst, Christian W.; Willemson, Jan; Pieters, Wolter

2016-01-01

The need to assess security and take protection decisions is at least as old as our civilisation. However, the complexity and development speed of our interconnected technical systems have surpassed our capacity to imagine and evaluate risk scenarios. This holds in particular for risks...... that are caused by the strategic behaviour of adversaries. Therefore, technology-supported methods are needed to help us identify and manage these risks. In this paper, we describe the attack navigator: a graph-based approach to security risk assessment inspired by navigation systems. Based on maps of a socio...

Derivation methods for clearance levels applied to reactors

International Nuclear Information System (INIS)

Okoshi, Minoru; Seki, Takeo

2001-01-01

In order to support the discussion by the Nuclear Safety Commission, JAERI derived the unconditional clearance levels for concrete and metal arising from the operation and dismantling of nuclear reactors. The clearance levels of 20 radionuclides were derived from 10 μSv/y of individual doses by deterministic approach. In this approach, calculation models were established to assess individual doses resulting from 73 exposure pathways related to disposal and recycle/reuse, and realistic parameter values were selected considering Japanese natural and social conditions. The appropriateness of selected parameter values was confirmed by stochastic analyses. (author)

The influence of body posture on lithium clearance

DEFF Research Database (Denmark)

Kamper, A L; Strandgaard, S; Holstein-Rathlou, N H

1988-01-01

measured four times at 1-week intervals: two in the supine and one in the sitting position, and one when the subject was walking around. Glomerular filtration rate was not influenced by posture changes. On the contrary, lithium clearance, which in the supine position was 30 +/- 9 ml/min (1 SD), tended...... during moderate physical activity. Hence, when renal tubular function is studied with the lithium clearance method, standardization of posture and physical activity is important. In such studies physical activity such as walking should particularly be avoided....

ANALYSIS OF FREE ROUTE AIRSPACE AND PERFORMANCE BASED NAVIGATION IMPLEMENTATION IN THE EUROPEAN AIR NAVIGATION SYSTEM

Directory of Open Access Journals (Sweden)

Svetlana Pavlova

2014-12-01

Full Text Available European Air Traffic Management system requires continuous improvements as air traffic is increasingday by day. For this purpose it was developed by international organizations Free Route Airspace and PerformanceBased Navigation concepts that allow to offer a required level of safety, capacity, environmental performance alongwith cost-effectiveness. The aim of the article is to provide detailed analysis of Free Route Airspace and PerformanceBased Navigation implementation status within European region including Ukrainian air navigation system.

Scan Manifestations and Blood Clearance Rates in Typhoid Liver

Energy Technology Data Exchange (ETDEWEB)

Bahk, Yong Whee; Ahn, Jae Sung; Kim, Soon Hi [St. Mary' s Hospital, Catholic Medical College, Seoul (Korea, Republic of)

1970-09-15

Fourteen patients with typhoid fever studied by scanning and clearance-rate measurements of subcritical dose colloidal radiogold ({sup 198}Au). Mild to moderate enlargement of the liver and spleen was noted in 78.6 and 64.3 percent of patients, respectively; and splenic and spinal bone-marrow uptake was seen in 78.6 and 57.1 percent of cases, respectively. Typically, these scan changes occurred concomitantly (57.1%) and are considered to represent increased phagocytic activity of the RE cells which is characteristic of typhoid fever. The half clearance-time was significantly shortened during the first 10-day period of the illness indicating an increase in the hepatic blood in the early phase of typhoid infection. Hepatomegaly, splenomegaly and extrahepatic uptakes along with an accelerated (or less a normal) clearance time are characteristic of typhoid fever.

Clearance of labelled creatinine

International Nuclear Information System (INIS)

Eberstadt, P.; Liverant, J.

1982-01-01

Creatinine, extensively used in clinical work to evaluate glomerular filtration rate (G.F.R.) has caused controversy. Using simultaneously on dogs a gamma emitting agent measuring G.F.R., creatinine clearance proved to be higher. Aided by quantitative determinations and compartmental analysis fortunately the respective dilution spaces can be calculated. In the majority of these animals creatinine spaces are larger but in some equal to the ones of inulin

SLS Model Based Design: A Navigation Perspective

Science.gov (United States)

Oliver, T. Emerson; Anzalone, Evan; Park, Thomas; Geohagan, Kevin

2018-01-01

The SLS Program has implemented a Model-based Design (MBD) and Model-based Requirements approach for managing component design information and system requirements. This approach differs from previous large-scale design efforts at Marshall Space Flight Center where design documentation alone conveyed information required for vehicle design and analysis and where extensive requirements sets were used to scope and constrain the design. The SLS Navigation Team is responsible for the Program-controlled Design Math Models (DMMs) which describe and represent the performance of the Inertial Navigation System (INS) and the Rate Gyro Assemblies (RGAs) used by Guidance, Navigation, and Controls (GN&C). The SLS Navigation Team is also responsible for navigation algorithms. The navigation algorithms are delivered for implementation on the flight hardware as a DMM. For the SLS Block 1B design, the additional GPS Receiver hardware model is managed as a DMM at the vehicle design level. This paper describes the models, and discusses the processes and methods used to engineer, design, and coordinate engineering trades and performance assessments using SLS practices as applied to the GN&C system, with a particular focus on the navigation components.

Applications of navigation for orthognathic surgery.

Science.gov (United States)

Bobek, Samuel L

2014-11-01

Stereotactic surgical navigation has been used in oral and maxillofacial surgery for orbital reconstruction, reduction of facial fractures, localization of foreign bodies, placement of implants, skull base surgery, tumor removal, temporomandibular joint surgery, and orthognathic surgery. The primary goals in adopting intraoperative navigation into these different surgeries were to define and localize operative anatomy, to localize implant position, and to orient the surgical wound. Navigation can optimize the functional and esthetic outcomes in patients with dentofacial deformities by identifying pertinent anatomic structures, transferring the surgical plan to the patient, and verifying the surgical result. This article discusses the principles of navigation-guided orthognathic surgery. Copyright © 2014 Elsevier Inc. All rights reserved.

Relationship of end-expiratory pressure, lung volume, and /sup 99m/Tc-DTPA clearance

International Nuclear Information System (INIS)

Cooper, J.A.; van der Zee, H.; Line, B.R.; Malik, A.B.

1987-01-01

We investigated the dose-response effect of positive end-expiratory pressure (PEEP) and increased lung volume on the pulmonary clearance rate of aerosolized technetium-99m-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA). Clearance of lung radioactivity was expressed as percent decrease per minute. Base-line clearance was measured while anesthetized sheep (n = 20) were ventilated with 0 cmH 2 O end-expiratory pressure. Clearance was remeasured during ventilation at 2.5, 5, 10, 15, or 20 cmH 2 O PEEP. Further studies showed stepwise increases in functional residual capacity (FRC) (P less than 0.05) measured at 0, 2.5, 5, 10, 15, and 20 cmH 2 O PEEP. At 2.5 cmH 2 O PEEP, the clearance rate was not different from that at base line (P less than 0.05), although FRC was increased from base line. Clearance rate increased progressively with increasing PEEP at 5, 10, and 15 cmH 2 O (P less than 0.05). Between 15 and 20 cmH 2 O PEEP, clearance rate was again unchanged, despite an increase in FRC. The pulmonary clearance of aerosolized /sup 99m/Tc-DTPA shows a sigmoidal response to increasing FRC and PEEP, having both threshold and maximal effects. This relationship is most consistent with the hypothesis that alveolar epithelial permeability is increased by lung inflation

Collective navigation of complex networks: Participatory greedy routing.

Science.gov (United States)

Kleineberg, Kaj-Kolja; Helbing, Dirk

2017-06-06

Many networks are used to transfer information or goods, in other words, they are navigated. The larger the network, the more difficult it is to navigate efficiently. Indeed, information routing in the Internet faces serious scalability problems due to its rapid growth, recently accelerated by the rise of the Internet of Things. Large networks like the Internet can be navigated efficiently if nodes, or agents, actively forward information based on hidden maps underlying these systems. However, in reality most agents will deny to forward messages, which has a cost, and navigation is impossible. Can we design appropriate incentives that lead to participation and global navigability? Here, we present an evolutionary game where agents share the value generated by successful delivery of information or goods. We show that global navigability can emerge, but its complete breakdown is possible as well. Furthermore, we show that the system tends to self-organize into local clusters of agents who participate in the navigation. This organizational principle can be exploited to favor the emergence of global navigability in the system.

Navigating the fifth dimension: new concepts in interactive multimodality and multidimensional image navigation

Science.gov (United States)

Ratib, Osman; Rosset, Antoine; Dahlbom, Magnus; Czernin, Johannes

2005-04-01

Display and interpretation of multi dimensional data obtained from the combination of 3D data acquired from different modalities (such as PET-CT) require complex software tools allowing the user to navigate and modify the different image parameters. With faster scanners it is now possible to acquire dynamic images of a beating heart or the transit of a contrast agent adding a fifth dimension to the data. We developed a DICOM-compliant software for real time navigation in very large sets of 5 dimensional data based on an intuitive multidimensional jog-wheel widely used by the video-editing industry. The software, provided under open source licensing, allows interactive, single-handed, navigation through 3D images while adjusting blending of image modalities, image contrast and intensity and the rate of cine display of dynamic images. In this study we focused our effort on the user interface and means for interactively navigating in these large data sets while easily and rapidly changing multiple parameters such as image position, contrast, intensity, blending of colors, magnification etc. Conventional mouse-driven user interface requiring the user to manipulate cursors and sliders on the screen are too cumbersome and slow. We evaluated several hardware devices and identified a category of multipurpose jogwheel device that is used in the video-editing industry that is particularly suitable for rapidly navigating in five dimensions while adjusting several display parameters interactively. The application of this tool will be demonstrated in cardiac PET-CT imaging and functional cardiac MRI studies.

Low serum hyaluronic acid levels associated with spontaneous HBsAg clearance

NARCIS (Netherlands)

Harkisoen, S.; Arends, J. E.; van den Hoek, A.; van Erpecum, K. J.; Boland, G. J.; Hoepelman, A. I. M.

2015-01-01

Purpose The pathophysiological underlying mechanism of spontaneous HBsAg clearance in hepatitis B virus (HBV) infected patients is largely unknown. However, serum hyaluronic acid (sHA) plays a role in liver fibrosis progression and reversely could serve as a potential biomarker for HBsAg clearance.

A pre- and postoperative study of split isotope clearance in childhood

International Nuclear Information System (INIS)

Faerber, D.; Czempiel, H.; Muehle, P.; Schick, F.; Wenzl, H.; Technische Univ. Muenchen; Technische Univ. Muenchen

1979-01-01

In 1978 43 patients have been operated in the Department of Pediatric Surgery, Krankenhaus Muenchen-Schwabing, because of recurrent urinary-tract infections with ureterovesical reflux or obstructive urinary-tract diseases. In all patients a split whole body clearance-study with a method modified after the method of Muehle with 131 J-Hippuran was carried out pre- or postoperatively, respectively. In 78,5% of these cases the clearance-results were corresponding to the results of X-ray examination; 6 of the remaining patients had a worse clearance result and 3 had a better result than the X-ray findings would have suggested. (orig.) [de

Scan Manifestation and Trace-Dose Radiogold Clearance Rates in Obstructive Jaundice

International Nuclear Information System (INIS)

Kim, Dong Jip; Bahk, Yong Whee; Shinn, Kyung Sub

1969-01-01

The present study has been undertaken to analyze scan manifestation in obstructive jaundice. Scan changes were correlated with the duration of jaundice. In addition, clearance rates of trace dose of colloidal radiogold were assessed in each case. The materials were consisted of 19 cases with surgically and/or histopathologically verified obstructive jaundice from various causes including common duct stone, empyema of the gall bladder and carcinoma of the pancreas head etc. Blood clearance rates of colloidal 198 Au were determined after the injection of 8 uCi by simple geometrical drawing of recorded strip charts. Scan was performed following additional injection of the sam radiogold. In 16 out of 19 cases, the scan rather typical 'arborifrom' mottlings around the porta hepatis. The intensity and appearance of such mottlings on the scan was related with the duration of jaundice and level of serum bilirubin and alkaline phosphatase. The blood clearance rates remained to be within normal range in 74 percent of the patients. In the remaining 26 percent, clearance rate ranged between 4.1 and 6 minutes. It is concluded that the association of 'arboriform' mottlings and normal or mildly delayed clearance rates in the patients with jaundice is characteristic of obstructive change in the biliary system.

Scan Manifestation and Trace-Dose Radiogold Clearance Rates in Obstructive Jaundice

Energy Technology Data Exchange (ETDEWEB)

Kim, Dong Jip; Bahk, Yong Whee; Shinn, Kyung Sub [Catholic University College of Medicine, Seoul (Korea, Republic of)

1969-09-15

The present study has been undertaken to analyze scan manifestation in obstructive jaundice. Scan changes were correlated with the duration of jaundice. In addition, clearance rates of trace dose of colloidal radiogold were assessed in each case. The materials were consisted of 19 cases with surgically and/or histopathologically verified obstructive jaundice from various causes including common duct stone, empyema of the gall bladder and carcinoma of the pancreas head etc. Blood clearance rates of colloidal {sup 198}Au were determined after the injection of 8 uCi by simple geometrical drawing of recorded strip charts. Scan was performed following additional injection of the sam radiogold. In 16 out of 19 cases, the scan rather typical 'arborifrom' mottlings around the porta hepatis. The intensity and appearance of such mottlings on the scan was related with the duration of jaundice and level of serum bilirubin and alkaline phosphatase. The blood clearance rates remained to be within normal range in 74 percent of the patients. In the remaining 26 percent, clearance rate ranged between 4.1 and 6 minutes. It is concluded that the association of 'arboriform' mottlings and normal or mildly delayed clearance rates in the patients with jaundice is characteristic of obstructive change in the biliary system.

Target relative navigation results from hardware-in-the-loop tests using the sinplex navigation system

NARCIS (Netherlands)

Steffes, S.; Dumke, M.; Heise, D.; Sagliano, M.; Samaan, M.; Theil, S.; Boslooper, E.C.; Oosterling, J.A.J.; Schulte, J.; Skaborn, D.; Söderholm, S.; Conticello, S.; Esposito, M.; Yanson, Y.; Monna, B.; Stelwagen, F.; Visee, R.

2014-01-01

The goal of the SINPLEX project is to develop an innovative solution to significantly reduce the mass of the navigation subsystem for exploration missions which include landing and/or rendezvous and capture phases. The system mass is reduced while still maintaining good navigation performance as

Time and Motion Study of a Community Patient Navigator

Directory of Open Access Journals (Sweden)

Sara S. Phillips

2014-04-01

Full Text Available Research on patient navigation has focused on validating the utility of navigators by defining their roles and analyzing their effects on patient outcomes, patient satisfaction, and cost effectiveness. Patient navigators are increasingly used outside the research context, and their roles without research responsibilities may look very different. This pilot study captured the activities of a community patient navigator for uninsured women with a positive screening test for breast cancer, using a time and motion approach over a period of three days. We followed the actions of this navigator minute by minute to assess the relative ratios of actions performed and to identify areas for time efficiency improvement to increase direct time with patients. This novel approach depicts the duties of a community patient navigator no longer fettered by navigation logs, research team meetings, surveys, and the consent process. We found that the community patient navigator was able to spend more time with patients in the clinical context relative to performing paperwork or logging communication with patients as a result of her lack of research responsibilities. By illuminating how community patient navigation functions as separate from the research setting, our results will inform future hiring and training of community patient navigators, system design and operations for improving the efficiency and efficacy of navigators, and our understanding of what community patient navigators do in the absence of research responsibilities.

Optical surgical navigation system causes pulse oximeter malfunction.

Science.gov (United States)

Satoh, Masaaki; Hara, Tetsuhito; Tamai, Kenji; Shiba, Juntaro; Hotta, Kunihisa; Takeuchi, Mamoru; Watanabe, Eiju

2015-01-01

An optical surgical navigation system is used as a navigator to facilitate surgical approaches, and pulse oximeters provide valuable information for anesthetic management. However, saw-tooth waves on the monitor of a pulse oximeter and the inability of the pulse oximeter to accurately record the saturation of a percutaneous artery were observed when a surgeon started an optical navigation system. The current case is thought to be the first report of this navigation system interfering with pulse oximetry. The causes of pulse jamming and how to manage an optical navigation system are discussed.

20 CFR 653.501 - Requirements for accepting and processing clearance orders.

Science.gov (United States)

2010-04-01

... the job order. (i) No agricultural or food processing order shall be included in job bank listings... clearance any job order seeking workers to perform agricultural or food processing work before reviewing it... order seeking workers to perform agricultural or food processing work into intrastate clearance unless...

10 CFR 95.21 - Withdrawal of requests for facility security clearance.

Science.gov (United States)

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Withdrawal of requests for facility security clearance. 95.21 Section 95.21 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) FACILITY SECURITY CLEARANCE AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION AND RESTRICTED DATA Physical Security § 95.21 Withdrawal of...

Clearance of insoluble dust from the lower respiratory tract

Energy Technology Data Exchange (ETDEWEB)

Morrow, P E; Gibb, F R; Johnson, L

1964-01-01

Clearance of tagged heavy metal aerosols (Fe, Hg, Mn, Ba, and U) in female beagles by in vivo counting was assessed. Fecal excretion paralleled lower respiratory tract clearance of Fe. No Fe was found in blood, indicating its biological insolubility. Ultrafiltration tests (an indication of biological solubility) ranked the heavy metals as: Hg, Mn, Fe, and U in order of decreasing solubility. The solubility ratios were remarkably similar to the ratios of inverse biological half-times.

33 CFR 117.458 - Inner Harbor Navigation Canal, New Orleans.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Inner Harbor Navigation Canal, New Orleans. 117.458 Section 117.458 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Harbor Navigation Canal, New Orleans. (a) The draws of the SR 46 (St. Claude Avenue) bridge, mile 0.5...

33 CFR 209.170 - Violations of laws protecting navigable waters.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Violations of laws protecting navigable waters. 209.170 Section 209.170 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF... navigable waters. (a) [Reserved] (b) Injuries to Government works. Section 14 of the River and Harbor Act of...

Fault-tolerant and Diagnostic Methods for Navigation

DEFF Research Database (Denmark)

Blanke, Mogens

2003-01-01

to diagnose faults and autonomously provide valid navigation data, disregarding any faulty sensor data and use sensor fusion to obtain a best estimate for users. This paper discusses how diagnostic and fault-tolerant methods are applicable in marine systems. An example chosen is sensor fusion for navigation......Precise and reliable navigation is crucial, and for reasons of safety, essential navigation instruments are often duplicated. Hardware redundancy is mostly used to manually switch between instruments should faults occur. In contrast, diagnostic methods are available that can use analytic redundancy...

Navigating ‘riskscapes’

DEFF Research Database (Denmark)

Gee, Stephanie; Skovdal, Morten

2017-01-01

This paper draws on interview data to examine how international health care workers navigated risk during the unprecedented Ebola outbreak in West Africa. It identifies the importance of place in risk perception, including how different spatial localities give rise to different feelings of threat...... or safety, some from the construction of physical boundaries, and others mediated through aspects of social relations, such as trust, communication and team dynamics. Referring to these spatial localities as ‘riskscapes’, the paper calls for greater recognition of the role of place in understanding risk...... perception, and how people navigate risk....

Dependence of 'CT clearance' on dosage and time

International Nuclear Information System (INIS)

Kaltenborn, H.A.; Klose, K.J.; Dexheimer, C.; Steinijans, V.

1989-01-01

The contrast medium dose used in CT renal function analysis corresponds to about 1 ml/kg body weight at a measurement interval of 5 or 10 minutes. In the present study the dependence of 'CT clearance' on dosage and time was examined in 12 healthy subjects. The amount of clearance was directly proportional to the employed contrast medium dose and to the length of the measurement interval. On account of the superior signal-to-noise ratio, the higher dose (1 ml/kg body weight) will continue to be prefered in future. The measurement interval can be limited to 10 minutes. (orig.) [de

Pulmonary epithelial clearance of 99mTc-DTPA after thrombin-induced pulmonary microembolism

International Nuclear Information System (INIS)

Cooper, J.A.; Feustel, P.J.; Line, B.R.; Malik, A.B.

1986-01-01

We investigated the effect of thrombin-induced pulmonary microembolism on the pulmonary clearance rate of aerosolized 99mTc diethylenetriamine pentaacetic acid (99mTc-DTPA) in awake, chronically prepared sheep. Chest activity was recorded after administration of a 0.44 micron aerosol of 99mTc-DTPA. Decay-corrected data were fit to an exponential and expressed as percent decrease per min (%/min). Sheep were given alpha-thrombin intravenously (80 U/kg for 10 min) 60 min after the aerosol administration. The clearance rate prior to alpha-thrombin was 0.35 +/- 0.05 %/min (mean +/- SEM). During alpha-thrombin administration, the clearance rate increased to 5.84 +/- 0.70 %/min (p less than 0.001 from baseline), but returned to 0.41 +/- 0.06 %/min within 30 min after the end of the thrombin infusion. The increased clearance rate during alpha-thrombin administration was not due to increased lung volume since alpha-thrombin did not change functional residual capacity. Moreover, the clearance rate was unchanged during gamma-thrombin administration, which does not induce coagulation, or during alpha-thrombin challenge in defibrinogenated animals. alpha-thrombin administration in neutrophil-depleted sheep caused a transient increase in DTPA clearance similar to that in control sheep, suggesting that the increase occurred independently of neutrophils. The results indicate that alpha-thrombin causes a large, transient increase in 99mTc-DTPA clearance, which may be the result of increased epithelial permeability. This response is dependent on the activation of intravascular coagulation

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... AWARENESS Tomorrow’s Leaders About Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With CF ... Chest Wall Oscillation (the Vest) Follow Us On Facebook Twitter YouTube Instagram Email Find a Clinical Trial Help us blaze ...

Magnetic navigation in a coronary phantom: experimental results.

Science.gov (United States)

García-García, Héctor M; Tsuchida, Keiichi; Meulenbrug, Hans; Ong, Andrew T L; Van der Giessen, Willem J; Serruys, Patrick W

2005-11-01

The objective was to investigate the efficacy of a magnetic navigation system (MNS) in a coronary phantom. The number of coronary interventional procedures performed is steadily increasing with the availability of new devices to treat more complex lesions. Vessel tortuosity remains an important limiting factor in percutaneous coronary intervention. The MNS can orient the tip of magnetized wire. The coronary phantom is a representation of the coronary tree. Two operators using both a magnetic wire and a standard wire, measured the procedural time (PT), the fluoroscopic time (FT) and the radiation exposure/area product (DAP) required to navigate through to fourteen segments. Ten wire advancements were performed per segment. In all but two segments, the PT was significantly longer using magnetic navigation than using manual navigation. The median FT in the left main artery (LMA) - first septal segment was 7 seconds vs. 18 seconds, with magnetic and manual navigation respectively, (p=0.05); in the LMA - obtuse marginal segment the median FT was 15 seconds with magnetic navigation vs. 29.5 seconds with manual navigation, (p=0.01); in the segment from proximal right coronary artery (RCA1) to the acute marginal branch, the median FT was 8 seconds with magnetic vs. 11 seconds with manual navigation, (p=0.05); and in the RCA1 -posterior descending segment the median FT was 9.5 seconds with magnetic vs. 15 seconds with manual navigation, (p=0.006). The MNS facilitates wire access to distal segments in a coronary phantom, with a reduction in FT and radiation exposure using magnetic navigation in tortuous segments.

Integrated INS/GPS Navigation from a Popular Perspective

Science.gov (United States)

Omerbashich, Mensur

2002-01-01

Inertial navigation, blended with other navigation aids, Global Positioning System (GPS) in particular, has gained significance due to enhanced navigation and inertial reference performance and dissimilarity for fault tolerance and anti-jamming. Relatively new concepts based upon using Differential GPS (DGPS) blended with Inertial (and visual) Navigation Sensors (INS) offer the possibility of low cost, autonomous aircraft landing. The FAA has decided to implement the system in a sophisticated form as a new standard navigation tool during this decade. There have been a number of new inertial sensor concepts in the recent past that emphasize increased accuracy of INS/GPS versus INS and reliability of navigation, as well as lower size and weight, and higher power, fault tolerance, and long life. The principles of GPS are not discussed; rather the attention is directed towards general concepts and comparative advantages. A short introduction to the problems faced in kinematics is presented. The intention is to relate the basic principles of kinematics to probably the most used navigation method in the future-INS/GPS. An example of the airborne INS is presented, with emphasis on how it works. The discussion of the error types and sources in navigation, and of the role of filters in optimal estimation of the errors then follows. The main question this paper is trying to answer is 'What are the benefits of the integration of INS and GPS and how is this, navigation concept of the future achieved in reality?' The main goal is to communicate the idea about what stands behind a modern navigation method.

Lactate clearance cut off for early mortality prediction in adult sepsis and septic shock patients

Science.gov (United States)

Sinto, R.; Widodo, D.; Pohan, H. T.

2018-03-01

Previous lactate clearance cut off for early mortality prediction in sepsis and septic shock patient was determined by consensus from small sample size-study. We investigated the best lactate clearance cut off and its ability to predict early mortality in sepsis and septic shock patients. This cohort study was conducted in Intensive Care Unit of CiptoMangunkusumo Hospital in 2013. Patients’ lactate clearance and eight other resuscitationendpoints were recorded, and theoutcome was observed during the first 120 hours. The clearance cut off was determined using receiver operating characteristic (ROC) analysis, and its ability was investigated with Cox’s proportional hazard regression analysis using other resuscitation endpoints as confounders. Total of 268 subjects was included, of whom 70 (26.11%) subjects died within the first 120 hours. The area under ROC of lactate clearance to predict early mortality was 0.78 (95% % confidence interval [CI] 0.71-0.84) with best cut off was <7.5% (sensitivity and specificity 88.99% and 81.4% respectively). Compared with group achieving lactate clearance target, group not achieving lactate clearance target had to increase early mortality risk (adjusted hazard ratio 13.42; 95%CI 7.19-25.07). In conclusion, the best lactate clearance cut off as anearly mortality predictor in sepsis and septic shock patients is 7.5%.

Numerical Investigation of Pressure Fluctuation Characteristics in a Centrifugal Pump with Variable Axial Clearance

Directory of Open Access Journals (Sweden)

Lei Cao

2016-01-01

Full Text Available Clearance flows in the sidewall gaps of centrifugal pumps are unsteady as well as main flows in the volute casing and impeller, which may cause vibration and noise, and the corresponding pressure fluctuations are related to the axial clearance size. In this paper, unsteady numerical simulations were conducted to predict the unsteady flows within the entire flow passage of a centrifugal pump operating in the design condition. Pressure fluctuation characteristics in the volute casing, impeller, and sidewall gaps were investigated with three axial clearance sizes. Results show that an axial clearance variation affects the pressure fluctuation characteristics in each flow domain by different degree. The greatest pressure fluctuation occurs at the blade pressure surface and is almost not influenced by the axial clearance variation which has a certainly effect on the pressure fluctuation characteristics around the tongue. The maximum pressure fluctuation amplitude in the sidewall gaps is larger than that in the volute casing, and different spectrum characteristics show up in the three models due to the interaction between the clearance flow and the main flow as well as the rotor-stator interaction. Therefore, clearance flow should be taken into consideration in the hydraulic design of centrifugal pumps.

Glomerular filtration in kidney recipients measured by plasma clearance of 169Yb-DTPA

International Nuclear Information System (INIS)

Stribrna, J.; Oppelt, A.; Jirickova, E.; Janata, V.; Kocandrle, V.; Sup, I.; Woller, P.; Franke, W.G.

1986-01-01

Values of 169 Yb-DTPA clearance (C DTPA ) calculated after a single injection were compared in 26 recipients of kidneys with renal clearance of inulin (C in ), polyfructosan S (C pf ) and creatinine (C cr ). In 21 patients the examinations were made simultaneously, in 5 patients C DTPA was measured within a short interval after the examination of renal clearance. The mean C DTPA values did not significantly differ from C cr but were significantly higher (p in and C pf (by 33% on average). Investigation of changes in C DTPA as compared with C in and C pf showed no significant difference in glomerular filtration (GF). This was measured using inulin and polyfructosan. The results showed that the differing molecular weight of inulin and polyfructosan S had no detectable effect on the GF of kidney recipients. The plasma clearance of 169 Yb-DTPA similarly to C cr overestimates the GF measured by inulin and polyfructosan clearance. (author)

A computer program for unilateral renal clearance calculation by a modified Oberhausen method

International Nuclear Information System (INIS)

Brueggemann, G.

1980-01-01

A FORTAN program is presented which, on the basis of data obtained with NUKLEOPAN M, calculates the glomerular filtration rate with sup(99m)Tc-DTPA, the unilateral effective renal plasma flow with 131 I-hippuran, and the parameters for describing the isotope rephrogram (ING) with 131 I-hippuran. The results are calculated fully automatically upon entry of the data, and the results are processed and printed out. The theoretical fundamentals of ING and whole-body clearance calculation are presented as well as the methods available for unilateral clearance calculation, and the FORTAN program is described in detail. The standard values of the method are documented, as well as a comparative gamma camera study of 48 patients in order to determine the accuracy of unilateral imaging with the NUKLEOPAN M instrument, a comparison of unilateral clearances by the Oberhausen and Taplin methods, and a comparison between 7/17' plasma clearance and whole-body clearance. Problems and findings of the method are discussed. (orig./MG) [de

Clearance, a powerful tool in optimizing the volume of radioactive wastes

International Nuclear Information System (INIS)

Blommaert, W.; Teunckens, L.

1997-01-01

In the framework its activities in decommissioning nuclear installations, Belgoprocess applies the clearance practice in optimizing the volume of radioactive wastes. The applied clearance methodology is discussed with special emphasis to different types of materials and to the associated measurements. Four practical cases are elaborated, dealing with the decommissioning and decontamination of two small buildings up to green field conditions, the unconditional release of large quantities of slightly contaminated active carbon, the melting and clearance of stainless steel fuel racks and of aluminium heat exchangers. The attention is drawn on practical problems associated with sampling and measurement strategies, in relation to the proposed low limits for unconditional release. (author)

Piles, tabs and overlaps in navigation among documents

DEFF Research Database (Denmark)

Jakobsen, Mikkel Rønne; Hornbæk, Kasper

2010-01-01

Navigation among documents is a frequent, but ill supported activity. Overlapping or tabbed documents are widespread, but they offer limited visibility of their content. We explore variations on navigation support: arranging documents with tabs, as overlapping windows, and in piles. In an experim......Navigation among documents is a frequent, but ill supported activity. Overlapping or tabbed documents are widespread, but they offer limited visibility of their content. We explore variations on navigation support: arranging documents with tabs, as overlapping windows, and in piles....... In an experiment we compared 11 participants’ navigation with these variations and found strong task effects. Overall, overlapping windows were preferred and their structured layout worked well with some tasks. Surprisingly, tabbed documents were efficient in tasks requiring simply finding a document. Piled...... on document navigation and its support by piling....

A review and comparison of international exemption and clearance levels

International Nuclear Information System (INIS)

Cooper, J.R.; Mobbs, S.F.

1997-01-01

The publication of new European Basic Safety Standards by the European Commission and of new International Basic Safety Standards by the IAEA together with other international agencies, has led to increased interest in the application of the concepts of exemption and clearance. This paper discusses the derivation of radionuclide-specific exemption and clearance values for application in various areas of the regulation of radioactive materials. (author)

Clearance measurements on activated parts of accelerators by combined methods; Verfahrenskombinierte Freigabemessung aktivierter Beschleunigerteile

Energy Technology Data Exchange (ETDEWEB)

Jansen, S.; Friedemann, S. [VKTA, Dresden (Germany); Enghardt, W. [Technische Univ. Dresden (Germany). OncoRay

2016-07-01

The process of clearance of radioactive materials according to paragraph 29 StrlSchV contents the comparison of activity to mass and surface of the material. To avoid a borderless assessment of activity of activation it is often necessary to use combined measurement methods: For clearance of collimators of a medical proton accelerator (energy range up to 200 MeV) it needs to know the nuclide composition. The energetical and geometrical calibration was fixed by experiments. The clearance based on measurements of activity distribution, gammaspectroscopy verification of nuclide composition and gamma-counting detectors. Parts of medical electron-accelerators achieved its clearance by combination of abovementioned methods and in-situ-gammaspectroscopy. Activated und contaminated lead stones achieved its clearance by measurements of fluence, laboratory evaluation of samples, in-situ-gammaspectroscopy and wipe tests.

An Integrated Approach to Electronic Navigation

National Research Council Canada - National Science Library

Shaw, Peter; Pettus, Bill

2001-01-01

While the Global Positioning System (GPS) is and will continue to be an excellent navigation system, it is neither flawless nor is it the only system employed in the navigation of today's seagoing warfighters...

Comparison of gas clearance and radioactive microspheres for pancreatic blood flow measurement

International Nuclear Information System (INIS)

DeMar, A.R.; Graham, L.S.; Lake, R.; Fink, A.S.

1989-01-01

Measurement of pancreatic blood flow (PBF) is technically demanding. Although radiolabeled microspheres are considered the gold standard for PBF assessment, they have practical limitations. In the current study, H 2 and xenon-133 gas clearance techniques were adapted to PBF measurement and compared to radiolabeled microsphere techniques. Simultaneous measurements of PBF were made using either hydrogen or xenon gas washout and radiolabeled microspheres. Measurements were made under basal, vasoconstricted (vasopressin 2U i.v. or nicotine 4 micrograms/kg/h) and stimulated (secretin 125 ng/kg/h or 2 U/kg i.v.) conditions (random order). Mean PBF was 26.9 +/- 5.3, 50.5 +/- 2.3 and 27.6 +/- 5.2 ml/min/100 g basally, 36.9 +/- 8.0, 90.1 +/- 18.9, and 81.7 +/- 14.5 ml/min/100 g in the stimulated state, and 24.2 +/- 7.8, 25.0 +/- 3.5, and 14.9 +/- 7.5 ml/min/100 g in the vasoconstricted state for hydrogen gas clearance, xenon gas clearance, and radiolabeled microspheres, respectively. The H 2 clearance technique resulted in tissue trauma, was complicated by frequent electrode displacement, and correlated poorly (r2 = 0.36, p greater than 0.05) with microsphere values. In contrast, xenon clearance measurement had no apparent effect on the pancreas and correlated well (r2 = 0.83, p less than 0.01) with microsphere data. We conclude that xenon clearance offers an attractive, validated alternative to radiolabeled microspheres for measuring pancreatic blood flow

Long-term clearance from small airways in subjects with ciliary dysfunction

Directory of Open Access Journals (Sweden)

Hjelte Lena

2006-05-01

Full Text Available Abstract The objective of this study was to investigate if long-term clearance from small airways is dependent on normal ciliary function. Six young adults with primary ciliary dyskinesia (PCD inhaled 111 Indium labelled Teflon particles of 4.2 μm geometric and 6.2 μm aerodynamic diameter with an extremely slow inhalation flow, 0.05 L/s. The inhalation method deposits particles mainly in the small conducting airways. Lung retention was measured immediately after inhalation and at four occasions up to 21 days after inhalation. Results were compared with data from ten healthy controls. For additional comparison three of the PCD subjects also inhaled the test particles with normal inhalation flow, 0.5 L/s, providing a more central deposition. The lung retention at 24 h in % of lung deposition (Ret24 was higher (p 24 with slow inhalation flow was 73.9 ± 1.9 % compared to 68.9 ± 7.5 % with normal inhalation flow in the three PCD subjects exposed twice. During day 7–21 the three PCD subjects exposed twice cleared 9 % with normal flow, probably representing predominantly alveolar clearance, compared to 19 % with slow inhalation flow, probably representing mainly small airway clearance. This study shows that despite ciliary dysfunction, clearance continues in the small airways beyond 24 h. There are apparently additional clearance mechanisms present in the small airways.

Fault-tolerant Sensor Fusion for Marine Navigation

DEFF Research Database (Denmark)

Blanke, Mogens

2006-01-01

Reliability of navigation data are critical for steering and manoeuvring control, and in particular so at high speed or in critical phases of a mission. Should faults occur, faulty instruments need be autonomously isolated and faulty information discarded. This paper designs a navigation solution...... where essential navigation information is provided even with multiple faults in instrumentation. The paper proposes a provable correct implementation through auto-generated state-event logics in a supervisory part of the algorithms. Test results from naval vessels document the performance and shows...... events where the fault-tolerant sensor fusion provided uninterrupted navigation data despite temporal instrument defects...

APPLICATION OF DSM IN OBSTACLE CLEARANCE SURVEYING OF AERODROME

Directory of Open Access Journals (Sweden)

X. Qiao

2016-06-01

Full Text Available Compared to the wide use of digital elevation model (DEM, digital surface model (DSM receives less attention because that it is composed by not only terrain surface, but also vegetations and man-made objects which are usually regarded as useless information. Nevertheless, these objects are useful for the identification of obstacles around an aerodrome. The primary objective of the study was to determine the applicability of DSM in obstacle clearance surveying of aerodrome. According to the requirements of obstacle clearance surveying at QT airport, aerial and satellite imagery were used to generate DSM, by means of photogrammetry, which was spatially analyzed with the hypothetical 3D obstacle limitation surfaces (OLS to identify the potential obstacles. Field surveying was then carried out to retrieve the accurate horizontal position and height of the obstacles. The results proved that the application of DSM could make considerable improvement in the efficiency of obstacle clearance surveying of aerodrome.

Dysregulation of Nutrient Sensing and CLEARance in Presenilin Deficiency

Directory of Open Access Journals (Sweden)

Kavya Reddy

2016-03-01

Full Text Available Attenuated auto-lysosomal system has been associated with Alzheimer disease (AD, yet all underlying molecular mechanisms leading to this impairment are unknown. We show that the amino acid sensing of mechanistic target of rapamycin complex 1 (mTORC1 is dysregulated in cells deficient in presenilin, a protein associated with AD. In these cells, mTORC1 is constitutively tethered to lysosomal membranes, unresponsive to starvation, and inhibitory to TFEB-mediated clearance due to a reduction in Sestrin2 expression. Normalization of Sestrin2 levels through overexpression or elevation of nuclear calcium rescued mTORC1 tethering and initiated clearance. While CLEAR network attenuation in vivo results in buildup of amyloid, phospho-Tau, and neurodegeneration, presenilin-knockout fibroblasts and iPSC-derived AD human neurons fail to effectively initiate autophagy. These results propose an altered mechanism for nutrient sensing in presenilin deficiency and underline an importance of clearance pathways in the onset of AD.

Effects of sustained exercise on pulmonary clearance of aerosolized 99mTc-DTPA

International Nuclear Information System (INIS)

Lorino, A.M.; Meignan, M.; Bouissou, P.; Atlan, G.

1989-01-01

The effects of intensive prolonged exercise on the pulmonary clearance rate of aerosolized 99m Tc-labeled diethylenetriaminepentaacetate ( 99m Tc-DTPA) and pulmonary mechanics were studied in seven healthy nonsmoking volunteers. 99m Tc-DTPA clearance and pulmonary mechanics (lung volumes and compliance) were assessed before and after 75 min of constant-load exercise performed on a treadmill, corresponding to 75% of maximal O 2 uptake. Because both clearance measurements were made in similar conditions of pulmonary blood flow, respiratory rate, and tidal volume, changes in clearance rate can be assumed to represent changes of alveolar epithelial permeability. After exercise, total, apical, and basal clearance were significantly increased (P less than 0.01, 0.05, and 0.05, respectively) and the increases in total clearance and tidal volume observed during exercise were significantly correlated (P less than 0.05). In contrast, no significant change was found in pulmonary mechanics. These results show that prolonged intensive exercise induces an increase in epithelial permeability, which appears to be related to the mechanical effects of sustained increased ventilation. Because no change was evidenced in pulmonary volumes or in lung elasticity, our results suggest that this increase may result from alteration of the intercellular tight junctions rather than from a surfactant deficiency

Higher Midazolam Clearance in Obese Adolescents Compared with Morbidly Obese Adults

NARCIS (Netherlands)

Rongen, van A.; Brill, M.J.E.; Vaughns, J.D.; Välitalo, P.A.J.; Dongen, van E.P.A.; Ramshorst, van B.; Barrett, J.S.; Anker, van den J.N.; Knibbe, C.A.J.

2017-01-01

The clearance of cytochrome P450 (CYP) 3A substrates is reported to be reduced with lower age, inflammation and obesity. As it is unknown what the overall influence is of these factors in the case of obese adolescents vs. morbidly obese adults, we studied covariates influencing the clearance of the

Navigation in Cross-cultural business relationships

DEFF Research Database (Denmark)

Andersen, Poul Houman

2001-01-01

Cross-cultural business navigation concerns the process of handling the complexity of several interacting cultural spheres of influence......Cross-cultural business navigation concerns the process of handling the complexity of several interacting cultural spheres of influence...

Comparative advantage between traditional and smart navigation systems

Science.gov (United States)

Shin, Jeongkyu; Kim, Pan-Jun; Kim, Seunghwan

2013-03-01

The smart navigation system that refers to real-time traffic data is believed to be superior to traditional navigation systems. To verify this belief, we created an agent-based traffic model and examined the effect of changing market share of the traditional shortest-travel-time algorithm based navigation and the smart navigation system. We tested our model on the grid and actual metropolitan road network structures. The result reveals that the traditional navigation system have better performance than the smart one as the market share of the smart navigation system exceeds a critical value, which is contrary to conventional expectation. We suggest that the superiority inversion between agent groups is strongly related to the traffic weight function form, and is general. We also found that the relationship of market share, traffic flow density and travel time is determined by the combination of congestion avoidance behavior of the smartly navigated agents and the inefficiency of shortest-travel-time based navigated agents. Our results can be interpreted with the minority game and extended to the diverse topics of opinion dynamics. This work was supported by the Original Technology Research Program for Brain Science through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology(No. 2010-0018847).

A fuzzy logic based navigation for mobile robot

International Nuclear Information System (INIS)

Adel Ali S Al-Jumaily; Shamsudin M Amin; Mohamed Khalil

1998-01-01

The main issue of intelligent robot is how to reach its goal safely in real time when it moves in unknown environment. The navigational planning is becoming the central issue in development of real-time autonomous mobile robots. Behaviour based robots have been successful in reacting with dynamic environment but still there are some complexity and challenging problems. Fuzzy based behaviours present as powerful method to solve the real time reactive navigation problems in unknown environment. We shall classify the navigation generation methods, five some characteristics of these methods, explain why fuzzy logic is suitable for the navigation of mobile robot and automated guided vehicle, and describe a reactive navigation that is flexible to react through their behaviours to the change of the environment. Some simulation results will be presented to show the navigation of the robot. (Author)

Axial compressor blade design for desensitization of aerodynamic performance and stability to tip clearance

Science.gov (United States)

Erler, Engin

Tip clearance flow is the flow through the clearance between the rotor blade tip and the shroud of a turbomachine, such as compressors and turbines. This flow is driven by the pressure difference across the blade (aerodynamic loading) in the tip region and is a major source of loss in performance and aerodynamic stability in axial compressors of modern aircraft engines. An increase in tip clearance, either temporary due to differential radial expansion between the blade and the shroud during transient operation or permanent due to engine wear or manufacturing tolerances on small blades, increases tip clearance flow and results in higher fuel consumption and higher risk of engine surge. A compressor design that can reduce the sensitivity of its performance and aerodynamic stability to tip clearance increase would have a major impact on short and long-term engine performance and operating envelope. While much research has been carried out on improving nominal compressor performance, little had been done on desensitization to tip clearance increase beyond isolated observations that certain blade designs such as forward chordwise sweep, seem to be less sensitive to tip clearance size increase. The current project aims to identify through a computational study the flow features and associated mechanisms that reduces sensitivity of axial compressor rotors to tip clearance size and propose blade design strategies that can exploit these results. The methodology starts with the design of a reference conventional axial compressor rotor followed by a parametric study with variations of this reference design through modification of the camber line and of the stacking line of blade profiles along the span. It is noted that a simple desensitization method would be to reduce the aerodynamic loading of the blade tip which would reduce the tip clearance flow and its proportional contribution to performance loss. However, with the larger part of the work on the flow done in this

Characterization and Clearance of m/s Sigyn

International Nuclear Information System (INIS)

Jiselmark, Jonatan; Vreede, Patrick

2016-01-01

M/s Sigyn was a 2044 ton ship that transported contaminated material between 1982 and 2013. Most of the transports were with spent nuclear fuel between Swedish nuclear power plants and the Swedish fuel repository, Clab. In addition to spent fuel, m/s Sigyn also transported big contaminated components, from nuclear power plants in Europe, to Studsvik for analysis or decontamination and melting. She also transported components from Swedish nuclear power plants to final disposal of short lived waste, SFR. Even though all transported items have been cleaned, checked and wrapped with plastics, some activity ended up as contamination onboard. In December 2013 it was decided that m/s Sigyn was subject for decommissioning due to her age. This Paper describes the method in which the activity onboard m/s Sigyn was characterized and clearance levels were calculated. This method for radiological characterization and clearance has recently been developed in Sweden, the method is efficient in that it does not need a big pre characterization survey. Only the nuclide distribution and history of the object, is needed to start the final survey. In the future there will be further development of the method, making it possible to reduce the number of measurements even more. This will further optimize the method and reduce the cost for final surveys and clearance. (authors)

Intelligent navigation to improve obstetrical sonography.

Science.gov (United States)

Yeo, Lami; Romero, Roberto

2016-04-01

'Manual navigation' by the operator is the standard method used to obtain information from two-dimensional and volumetric sonography. Two-dimensional sonography is highly operator dependent and requires extensive training and expertise to assess fetal anatomy properly. Most of the sonographic examination time is devoted to acquisition of images, while 'retrieval' and display of diagnostic planes occurs rapidly (essentially instantaneously). In contrast, volumetric sonography has a rapid acquisition phase, but the retrieval and display of relevant diagnostic planes is often time-consuming, tedious and challenging. We propose the term 'intelligent navigation' to refer to a new method of interrogation of a volume dataset whereby identification and selection of key anatomical landmarks allow the system to: 1) generate a geometrical reconstruction of the organ of interest; and 2) automatically navigate, find, extract and display specific diagnostic planes. This is accomplished using operator-independent algorithms that are both predictable and adaptive. Virtual Intelligent Sonographer Assistance (VIS-Assistance®) is a tool that allows operator-independent sonographic navigation and exploration of the surrounding structures in previously identified diagnostic planes. The advantage of intelligent (over manual) navigation in volumetric sonography is the short time required for both acquisition and retrieval and display of diagnostic planes. Intelligent navigation technology automatically realigns the volume, and reorients and standardizes the anatomical position, so that the fetus and the diagnostic planes are consistently displayed in the same manner each time, regardless of the fetal position or the initial orientation. Automatic labeling of anatomical structures, subject orientation and each of the diagnostic planes is also possible. Intelligent navigation technology can operate on conventional computers, and is not dependent on specific ultrasound platforms or on the

Ecodesign Navigator

DEFF Research Database (Denmark)

Simon, M; Evans, S.; McAloone, Timothy Charles

The Ecodesign Navigator is the product of a three-year research project called DEEDS - DEsign for Environment Decision Support. The initial partners were Manchester Metropolitan University, Cranfield University, Engineering 6 Physical Sciences Resaech Council, Electrolux, ICL, and the Industry...

A stochastic approach to the derivation of exemption and clearance levels

International Nuclear Information System (INIS)

Deckert, A.

1997-01-01

Deciding what clearance levels are appropriate for a particular waste stream inherently involves a number of uncertainties. Some of these uncertainties can be quantified using stochastic modeling techniques, which can aid the process of decision making. In this presentation the German approach to dealing with the uncertainties involved in setting clearance levels is addressed. (author)

Metrics for evaluating patient navigation during cancer diagnosis and treatment: crafting a policy-relevant research agenda for patient navigation in cancer care.

Science.gov (United States)

Guadagnolo, B Ashleigh; Dohan, Daniel; Raich, Peter

2011-08-01

Racial and ethnic minorities as well as other vulnerable populations experience disparate cancer-related health outcomes. Patient navigation is an emerging health care delivery innovation that offers promise in improving quality of cancer care delivery to these patients who experience unique health-access barriers. Metrics are needed to evaluate whether patient navigation can improve quality of care delivery, health outcomes, and overall value in health care during diagnosis and treatment of cancer. Information regarding the current state of the science examining patient navigation interventions was gathered via search of the published scientific literature. A focus group of providers, patient navigators, and health-policy experts was convened as part of the Patient Navigation Leadership Summit sponsored by the American Cancer Society. Key metrics were identified for assessing the efficacy of patient navigation in cancer diagnosis and treatment. Patient navigation data exist for all stages of cancer care; however, the literature is more robust for its implementation during prevention, screening, and early diagnostic workup of cancer. Relatively fewer data are reported for outcomes and efficacy of patient navigation during cancer treatment. Metrics are proposed for a policy-relevant research agenda to evaluate the efficacy of patient navigation in cancer diagnosis and treatment. Patient navigation is understudied with respect to its use in cancer diagnosis and treatment. Core metrics are defined to evaluate its efficacy in improving outcomes and mitigating health-access barriers. Copyright © 2011 American Cancer Society.

Shape Perception and Navigation in Blind Adults

Science.gov (United States)

Gori, Monica; Cappagli, Giulia; Baud-Bovy, Gabriel; Finocchietti, Sara

2017-01-01

Different sensory systems interact to generate a representation of space and to navigate. Vision plays a critical role in the representation of space development. During navigation, vision is integrated with auditory and mobility cues. In blind individuals, visual experience is not available and navigation therefore lacks this important sensory signal. In blind individuals, compensatory mechanisms can be adopted to improve spatial and navigation skills. On the other hand, the limitations of these compensatory mechanisms are not completely clear. Both enhanced and impaired reliance on auditory cues in blind individuals have been reported. Here, we develop a new paradigm to test both auditory perception and navigation skills in blind and sighted individuals and to investigate the effect that visual experience has on the ability to reproduce simple and complex paths. During the navigation task, early blind, late blind and sighted individuals were required first to listen to an audio shape and then to recognize and reproduce it by walking. After each audio shape was presented, a static sound was played and the participants were asked to reach it. Movements were recorded with a motion tracking system. Our results show three main impairments specific to early blind individuals. The first is the tendency to compress the shapes reproduced during navigation. The second is the difficulty to recognize complex audio stimuli, and finally, the third is the difficulty in reproducing the desired shape: early blind participants occasionally reported perceiving a square but they actually reproduced a circle during the navigation task. We discuss these results in terms of compromised spatial reference frames due to lack of visual input during the early period of development. PMID:28144226

A simultaneous navigation and radiation evasion algorithm (SNARE)

Energy Technology Data Exchange (ETDEWEB)

Khasawneh, Mohammed A., E-mail: mkha@ieee.org [Department of Electrical Engineering, Jordan University of Science and Technology, Irbid 221 10 (Jordan); Jaradat, Mohammad A., E-mail: majaradat@just.edu.jo [Department of Mechanical Engineering, Jordan University of Science and Technology, Irbid 221 10 (Jordan); Al-Shboul, Zeina Aman M., E-mail: xeinaaman@gmail.com [Department of Electrical Engineering, Jordan University of Science and Technology, Irbid 221 10 (Jordan)

2013-12-15

Highlights: • A new navigation algorithm for radiation evasion around nuclear facilities. • An optimization criteria minimized under algorithm operation. • A man-borne device guiding the occupational worker towards paths that warrant least radiation × time products. • Benefits of using localized navigation as opposed to global navigation schemas. • A path discrimination function for finding the navigational paths exhibiting the least amounts of radiation. - Abstract: In this paper, we address the issue of localization as pertains to indoor navigation under radiation contaminated environments. In this context, navigation, in the absence of any GPS signals, is guided by the location of the sensors that make up the entire wireless sensor network in a given locality within a nuclear facility. It, also, draws on the radiation levels as measured by the sensors around a given locale. Here, localization is inherently embedded into the algorithm presented in (Khasawneh et al., 2011a, 2011b) which was designed to provide navigational guidance to optimize any of two criteria: “Radiation Evasion” and “Nearest Exit”. As such, the algorithm can either be applied to setting a navigational “lowest” radiation exposure path from an initial point A to some other point B; a case typical of occupational workers performing maintenance operations around the facility; or providing a radiation-safe passage from point A to the nearest exit. Algorithm's navigational performance is tested under statistical reference, wherein for a given number of runs (trials) algorithm performance is evaluated as a function of the number of steps of look-ahead it uses to acquire navigational information, and is compared against the performance of the renowned Dijkstra global navigation algorithm. This is done with reference to the amount of (radiation × time) product and that of the time needed to reach an exit point, under the two optimization criteria. To evaluate algorithm

A simultaneous navigation and radiation evasion algorithm (SNARE)

International Nuclear Information System (INIS)

Khasawneh, Mohammed A.; Jaradat, Mohammad A.; Al-Shboul, Zeina Aman M.

2013-01-01

Highlights: • A new navigation algorithm for radiation evasion around nuclear facilities. • An optimization criteria minimized under algorithm operation. • A man-borne device guiding the occupational worker towards paths that warrant least radiation × time products. • Benefits of using localized navigation as opposed to global navigation schemas. • A path discrimination function for finding the navigational paths exhibiting the least amounts of radiation. - Abstract: In this paper, we address the issue of localization as pertains to indoor navigation under radiation contaminated environments. In this context, navigation, in the absence of any GPS signals, is guided by the location of the sensors that make up the entire wireless sensor network in a given locality within a nuclear facility. It, also, draws on the radiation levels as measured by the sensors around a given locale. Here, localization is inherently embedded into the algorithm presented in (Khasawneh et al., 2011a, 2011b) which was designed to provide navigational guidance to optimize any of two criteria: “Radiation Evasion” and “Nearest Exit”. As such, the algorithm can either be applied to setting a navigational “lowest” radiation exposure path from an initial point A to some other point B; a case typical of occupational workers performing maintenance operations around the facility; or providing a radiation-safe passage from point A to the nearest exit. Algorithm's navigational performance is tested under statistical reference, wherein for a given number of runs (trials) algorithm performance is evaluated as a function of the number of steps of look-ahead it uses to acquire navigational information, and is compared against the performance of the renowned Dijkstra global navigation algorithm. This is done with reference to the amount of (radiation × time) product and that of the time needed to reach an exit point, under the two optimization criteria. To evaluate algorithm

Off the Beaten tracks: Exploring Three Aspects of Web Navigation

NARCIS (Netherlands)

Weinreich, H.; Obendorf, H.; Herder, E.; Mayer, M.; Edmonds, H.; Hawkey, K.; Kellar, M.; Turnbull, D.

2006-01-01

This paper presents results of a long-term client-side Web usage study, updating previous studies that range in age from five to ten years. We focus on three aspects of Web navigation: changes in the distribution of navigation actions, speed of navigation and within-page navigation. “Navigation

Modelling of Outer and Inner Film Oil Pressure for Floating Ring Bearing Clearance in Turbochargers

International Nuclear Information System (INIS)

Zhang Hao; Shi Zhanqun; Gu Fengshou; Ball, Andrew

2011-01-01

Floating ring bearing is widely used in turbochargers to undertake the extreme condition of high rotating speed and high operating temperature. It is also the most concerned by the designers and users alike due to its high failure rate and high maintenance cost. Any little clearance change may result in oil leakage, which in turn cause blue smoke or black smoke according to leakage types. However, there is no condition monitoring of this bearing because it is almost impossible to measure the clearance especially the inner clearance, in which the inner oil film directly bears the high speed rotation. In stead of measuring clearance directly, this paper has proposed a method that uses film pressure as a measure to monitor the bearing clearance and its variation. A non-linear mathematical model is developed by using Reynolds equations with non-linear oil film pressure. A full description of the outer and inner film is provided along both axial and radial directions. A numerical simulation is immediately carried out. Variable clearance changes are investigated using the mathematical model. Results show the relationship between clearance and film pressure.

Comparison between total and renal plasma clearance of [51Cr]EDTA

International Nuclear Information System (INIS)

Broechner-Mortensen, J.; Roedbro, P.

1976-01-01

The total plasma (E 1 ) and renal plasma (E 2 ) clearances of [ 51 Cr]EDTA were measured simultaneously in 40 patients with a wide range of renal function. The regression equation was E 1 = 0.997E 2 + 4.1; the slope of the regression line was not significantly different from 1.00, and the intercept differed significantly from zero. The results suggest that [ 51 Cr]EDTA has a significant extrarenal clearance of approximately 4 ml/min, independent of renal function. The data are used to correct the total [ 51 Cr]EDTA plasma clearance, measured by a simplified method, to yield a rapid, accurate and precise measurement of glomerular filtration rate for routine clinical use. (Auth.)

Responsibility navigator

NARCIS (Netherlands)

Kuhlmann, Stefan; Edler, Jakob; Ordonez Matamoros, Hector Gonzalo; Randles, Sally; Walhout, Bart; Walhout, Bart; Gough, Clair; Lindner, Ralf; Lindner, Ralf; Kuhlmann, Stefan; Randles, Sally; Bedsted, Bjorn; Gorgoni, Guido; Griessler, Erich; Loconto, Allison; Mejlgaard, Niels

2016-01-01

Research and innovation activities need to become more responsive to societal challenges and concerns. The Responsibility Navigator, developed in the Res-AGorA project, supports decision-makers to govern such activities towards more conscious responsibility. What is considered “responsible” will

Traffic Incident Clearance Time and Arrival Time Prediction Based on Hazard Models

Directory of Open Access Journals (Sweden)

Yang beibei Ji

2014-01-01

Full Text Available Accurate prediction of incident duration is not only important information of Traffic Incident Management System, but also an effective input for travel time prediction. In this paper, the hazard based prediction models are developed for both incident clearance time and arrival time. The data are obtained from the Queensland Department of Transport and Main Roads’ STREAMS Incident Management System (SIMS for one year ending in November 2010. The best fitting distributions are drawn for both clearance and arrival time for 3 types of incident: crash, stationary vehicle, and hazard. The results show that Gamma, Log-logistic, and Weibull are the best fit for crash, stationary vehicle, and hazard incident, respectively. The obvious impact factors are given for crash clearance time and arrival time. The quantitative influences for crash and hazard incident are presented for both clearance and arrival. The model accuracy is analyzed at the end.

Production of plastic scintillation survey meter for clearance verification measurement

International Nuclear Information System (INIS)

Tachibana, Mitsuo; Shiraishi, Kunio; Ishigami, Tsutomu; Tomii, Hiroyuki

2008-03-01

In the Nuclear Science Research Institute, the decommissioning of various nuclear facilities is carried out according to the plan for meeting the midterm goal of the Japan Atomic Energy Agency (JAEA). An increase in the clearance verification measurement of concrete on buildings and the radiation measurement for releasing controlled areas will be expected along with the dismantlement of nuclear facilities in the future. The radiation measurement for releasing controlled areas has been carried out in small-scale nuclear facilities including the JPDR (Japan Power Demonstration Reactor). However, the radiation measurement with an existing measuring device was difficult in effects of radiation from radioactive materials that remains in buried piping. On the other hand, there is no experience that the clearance verification measurement is executed in the JAEA. The generation of a large amount of clearance object will be expected along with the decommissioning of the nuclear facilities in the future. The plastic scintillation survey meter (hereafter, 'PL measuring device') was produced to apply to the clearance verification measurement and the radiation measurement for releasing controlled areas. The basic characteristic test and the actual test were confirmed using the PL measuring device. As a result of these tests, it was found that the evaluation value of radioactivity with the PL measuring device was accuracy equal with the existing measuring device. The PL measuring device has feature of the existing measuring device with a light weight and easy operability. The PL measuring device can correct the gamma ray too. The PL measuring device is effective to the clearance verification measurement of concrete on buildings and the radiation measurement for releasing controlled areas. (author)

[Airway clearance techniques in chronic obstructive pulmonary syndrome : 2011 update].

Science.gov (United States)

Opdekamp, C

2011-09-01

For many years the airway clearance techniques used in chest physical therapy were assimilated with the singular technique of postural drainage, percussions and vibrations. However the side effects and counter indications and the lack of scientific proof regarding this technique have forced reflection and development of other techniques more comfortable and without deleterious effects. If all these techniques show a high efficiency in terms of improved mucociliary clearance, the literature is unanimous on how little effect these techniques have in the short and the long-term with regards to lung function and arterial blood gases. In view of the scientific literature, it is clear that the airway clearance techniques don't have the same recognition concerning their efficiency in all obstructive pulmonary diseases. As the cornerstone in the management of cystic fibrosis, the efficiency of the bronchial hygiene techniques are in general poorly documented in the management of the non-cystic fibrosis bronchiectasis, bronchitis or emphysema. The use of the chest physical therapy seems more to do with the interpretation of the imagery and symptomatology. The airway clearance techniques should be individualised according to symptoms, the amount of expectorated mucus and the objectives signs of secretions retention or subjective signs of difficulty expectorating secretions with progression of the disease.

Factors affecting lower calyceal stone clearance after Extracorporeal shock wave lithotripsy

Directory of Open Access Journals (Sweden)

S. Azab

2013-03-01

Conclusions: There is no statistically significant effect of stone size, anatomy of the lower calyx and BMI on stone clearance after ESWL of lower calyceal stones. However, small stone size (≤2 cm, a shorter and wider infundibulum and a larger lower-pole infundibulopelvic angle seem to promote a more rapid and more complete stone clearance.

Chromium-51-EDTA clearance in adults with a single-plasma sample.

Science.gov (United States)

Mårtensson, J; Groth, S; Rehling, M; Gref, M

1998-12-01

In 1996, a committee on renal clearance recommended a mean sojourn time-based methodology for single-sample determination of plasma clearance of 99mTc-diethylenetriamine pentaacetic acid (DTPA) to be used on adults if the patient's glomerular filtration rate (GFR) is suspected to be >30 ml/min. The main purpose of this study was to derive a mean sojourn time-based formula for calculation of 51Cr-ethylenediamine tetraacetic acid (EDTA) clearance in adults. Two groups of patients with 51Cr-EDTA clearance (Cl) between 16 and 172 ml/min were studied. In Group I (n = 46), reference Cl was determined as a multiplasma sample, single-injection method (ClSM). Sixteen blood samples were drawn from 0 until 5 hr after a single intravenous injection of 51Cr-EDTA. In Group II (n = 1046), reference Cl was determined by the Brøchner-Mortensen four-sample clearance method (ClBM). The plasma time-activity curves of Group I were used to derive two mean sojourn time-based formulas (Formulas 1 and 2) for calculation of a single-sample clearance. Formula 1 was derived from the entire time-activity curve, whereas the derivation of Formula 2 used only the final slope of the time-activity curve. The accuracy of the two formulas and the Christensen and Groth 99mTc-DTPA formula was tested on Group II. Chromium-51-EDTA Cl calculated by Formula 1 was almost identical to the Cl calculated by the reference Cl method (r = 0.982; SDdiff = 5.82 ml/min). Both 51Cr-EDTA Cl calculated by Formula 2 and by the 99mTc-DTPA formula showed close correlation with the reference method (r = 0.976, r = 0.985, respectively) but systematically overestimated GFR for the whole range of clearance values by 3.5 and 3.2 ml/min (ptime methodology. The determination is marginally more accurate (ptime-activity curve than from only the final slope. The single-sample formula derived for determination of 99mTc-DTPA Cl tends slightly to overestimate GFR if used to calculate 51Cr-EDTA Cl.

Clearance of material with negligible levels of radioactivity based on the amended German radiation protection ordinance

International Nuclear Information System (INIS)

Schaller, G.; Bayer, A.

2002-01-01

For the first time the modalities for the clearance of relevant materials have been laid down in the amended Radiation Protection Ordinance in a comprehensive form. A distinction is made between unconditional clearance and cases of clearance in which disposal, recycling, and re-use is prescribed. The focus of attention in the case of unconditional clearance consists in special consideration of large volumes of building rubble and excavated soil. Material can only be released from supervision under the Atomic Energy Act, when the radiation-related risk, and correspondingly, also the dose from material issued with clearance, are at negligible levels. In order to facilitate the practical application of clearance, values have been derived on the basis of scenarios which cover all radiation exposures which can reasonably be considered. (orig.) [de

Letting in-vehicle navigation lead the way: Older drivers' perceptions of and ability to follow a GPS navigation system.

Science.gov (United States)

Stinchcombe, Arne; Gagnon, Sylvain; Kateb, Matthew; Curtis, Meredith; Porter, Michelle M; Polgar, Jan; Bédard, Michel

2017-09-01

In-vehicle navigation systems have the potential to simplify the driving task by reducing the drivers' need to engage in wayfinding, especially in unfamiliar environments. This study sought to characterize older drivers' overall assessment of using in-vehicle GPS technology as part of a research study and to explore whether the use of this technology has an impact on participants' driving behaviour. Forty-seven older drivers completed an on-road evaluation where directions were provided by an in-vehicle GPS navigation system and their behaviour was recorded using video technology. They later completed a questionnaire to assess their perception of the navigation system. After the study, participants were grouped based on whether they were able to accurately follow the instructions provided by the navigation system. The results indicated that most drivers were satisfied with the navigation technology and found the directions it provided to be clear. There were no statistically significant differences in the number of on-road errors committed by drivers who did not follow the directions from the navigation system in comparison to drivers who did follow the directions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cloud Absorption Radiometer Autonomous Navigation System - CANS

Science.gov (United States)

Kahle, Duncan; Gatebe, Charles; McCune, Bill; Hellwig, Dustan

2013-01-01

CAR (cloud absorption radiometer) acquires spatial reference data from host aircraft navigation systems. This poses various problems during CAR data reduction, including navigation data format, accuracy of position data, accuracy of airframe inertial data, and navigation data rate. Incorporating its own navigation system, which included GPS (Global Positioning System), roll axis inertia and rates, and three axis acceleration, CANS expedites data reduction and increases the accuracy of the CAR end data product. CANS provides a self-contained navigation system for the CAR, using inertial reference and GPS positional information. The intent of the software application was to correct the sensor with respect to aircraft roll in real time based upon inputs from a precision navigation sensor. In addition, the navigation information (including GPS position), attitude data, and sensor position details are all streamed to a remote system for recording and later analysis. CANS comprises a commercially available inertial navigation system with integral GPS capability (Attitude Heading Reference System AHRS) integrated into the CAR support structure and data system. The unit is attached to the bottom of the tripod support structure. The related GPS antenna is located on the P-3 radome immediately above the CAR. The AHRS unit provides a RS-232 data stream containing global position and inertial attitude and velocity data to the CAR, which is recorded concurrently with the CAR data. This independence from aircraft navigation input provides for position and inertial state data that accounts for very small changes in aircraft attitude and position, sensed at the CAR location as opposed to aircraft state sensors typically installed close to the aircraft center of gravity. More accurate positional data enables quicker CAR data reduction with better resolution. The CANS software operates in two modes: initialization/calibration and operational. In the initialization/calibration mode

Transplacental clearance and blood flows of bovine gravid uterus at several stages of gestation

International Nuclear Information System (INIS)

Reynolds, L.P.; Ferrell, C.L.

1987-01-01

Rates of uterine and umbilical blood flows and transplacental clearance of deuterium oxide (D 2 O) were determined for cows on 137 +/- 1.0 (SE, n = 9), 180 +/- 0.5 (n = 8), 226 +/- 0.4 (n = 9), and 250 +/- 1.8 (n = 5) days of gestation. From days 137 to 250, rates increased 4.5-fold for uterine blood flow, 21-fold for umbilical blood flow, and 14-fold for clearance of D 2 O. Changes in rates of umbilical blood flow and D 2 O clearance paralleled increased rates of fetal growth and metabolism, which have previously been reported to occur during the last half of gestation. The regressions of D 2 O clearance on uterine and umbilical blood flows were significant (P less than 0.01) and explained 94-99% of the variation in placental clearance of D 2 O. Because the rate of D 2 O clearance was always less than that of uterine and umbilical blood flows, and because a relatively simple statistical model explained most of the variation in clearance, it was suggested that a concurrent or countercurrent arrangement of maternal and fetal placental microvasculatures is not adequate to explain clearance of highly diffusable substances across the bovine placenta. In addition, a placental exchange diagram of the data showed the existence of severe uneven distribution of maternal and fetal placental blood flows and/or significant shunting of maternal and fetal placental flows away from areas of exchange. Taken together, these data indicate that the placenta of the cow, like those of the sheep and goat, represents a relatively inefficient system of transplacental exchange

Limitations of regional myocardial thallium clearance for identification of disease in individual coronary arteries

International Nuclear Information System (INIS)

Becker, L.C.; Rogers, W.J. Jr.; Links, J.M.; Corn, C.

1989-01-01

The purpose of this study was to critically evaluate the usefulness of postexercise regional myocardial thallium-201 clearance for identifying disease in individual coronary arteries. Exercise and redistribution planar imaging studies were performed in 114 subjects, including 19 normal volunteers and 95 patients undergoing cardiac catheterization (70 with and 25 without greater than or equal to 50% narrowing in one or more coronary arteries). Thallium clearance was measured from predefined myocardial regions corresponding to the left anterior descending, left circumflex and right coronary arteries and was expressed as the percent decrease in activity at 4 h, assuming monoexponential clearance. In regions perfused by a normal or insignificantly diseased coronary artery, mean 4 h clearance was 58.9 +/- 9.4% for normal volunteers, 43.1 +/- 15.5% for catheterized patients without coronary artery disease and 36.3 +/- 24.9% for catheterized patients with coronary artery disease (p less than 0.001 patients with coronary artery disease versus normal volunteers). Clearance from normal regions was significantly associated with two measures of exercise performance: percent of predicted maximal heart rate achieved (r = 0.49) and exercise duration (r = 0.35). In regions perfused by a stenotic coronary artery, mean clearance was lower (31.1 +/- 19.8%) but was not significantly different from that in normal regions in the same patients. Clearance from diseased regions was also associated with maximal exercise heart rate (r = 0.28) and exercise duration (r = 0.41), but not with percent coronary artery stenosis (r = 0.02). After taking exercise performance into account, the number of diseased vessels or the presence or absence of disease in a given vessel had little influence on regional thallium clearance

Small solute clearance from the lungs of patients with cardiogenic and noncardiogenic pulmonary edema

International Nuclear Information System (INIS)

Mason, G.R.; Effros, R.M.; Uszler, J.M.; Mena, I.

1985-01-01

The regional clearance of /sup 99m/Tc-diethylenetriamine penta-acetate from the lungs was measured in 14 patients with noncardiogenic pulmonary edema, six patients with acute pulmonary edema secondary to heart failure, and 29 normal subjects. The radionuclide was delivered in an aerosol which was inhaled for 120 seconds, and the subsequent decline of radioactivity from the lungs was monitored for seven minutes over each of six peripheral regions of interest with a computerized scintillation camera. The average /sup 99m/Tc-DTPA clearance of these regions was accelerated above the 98 percent confidence limits in all but three of the patients with noncardiogenic edema. The mean clearance value in this group of patients was significantly greater than those in normal subjects or patients with cardiogenic pulmonary edema. Clearances returned toward normal in each of seven subjects who improved clinically. Only one of the patients with cardiogenic pulmonary edema had an elevated average clearance rate, and the mean clearance for this population was not statistically greater than normal. This procedure appears to detect increased epithelial permeability caused by lung injury and may help distinguish between cardiogenic and noncardiogenic pulmonary edema

Waste-clearance strategy for DOE waste processed at commercial facilities

International Nuclear Information System (INIS)

Chen, S.Y.; Pfingston, M.; LePoire, D.

1996-01-01

In May 1991, a moratorium was issued on shipping potentially mixed waste from DOE facilities nationwide to commercial treatment, storage, and disposal facilities. A potential waste-clearance strategy was developed to address the DOE mixed-waste moratorium issues, which had resulted from a lack of exisitng volume contamination regulations. This strategy also has important potential applications for establishing site clearance limits that ensure worker and public risks remain well below regulatory limits

Plasma clearance of noradrenaline does not change with age in normal subjects

DEFF Research Database (Denmark)

Hilsted, J; Christensen, N J; Larsen, S

1985-01-01

Noradrenaline kinetics (plasma concentrations, plasma clearance and appearance rates) were investigated in seven elderly healthy subjects and in six young healthy subjects. Forearm venous plasma noradrenaline concentrations were higher in the elderly subjects compared with the young subjects. Pla....... Plasma clearance of noradrenaline was identical in the two groups. The increase in plasma noradrenaline concentration, with age, probably reflects an increased sympathetic nervous activity.......Noradrenaline kinetics (plasma concentrations, plasma clearance and appearance rates) were investigated in seven elderly healthy subjects and in six young healthy subjects. Forearm venous plasma noradrenaline concentrations were higher in the elderly subjects compared with the young subjects...

Ballistic Aspects of Feasibility for Prospective Satellite Navigation Technologies

Directory of Open Access Journals (Sweden)

L. N. Lysenko

2015-01-01

Full Text Available When modeling the operating processes of ballistics and navigation support it is expedient to make decomposition of the general problem of coordinate-time and navigation support into the typical options of its engineering implementation.As the satellite navigation technologies the paper considers inter-satellite measurement and autonomous navigation mode of differential correction. It also assesses the possibility of their application to improve the accuracy of navigation determinations.Technologies using inter-satellite measurement tools such as GLONASS / GPS equipment, equipment of inter-satellite radio link, astro-optical space based devices are an independent class of navigation technologies.However, each of these options has both advantages and disadvantages that affect the eva luation of the appropriateness and feasibility of their use.The paper separately considers the problem of increasing survivability of space systems and conservation of ground control complex due to introduction of requirements to ensure the independent functioning of spacecraft and application of technologies of ballistics and navigation support, supposing to involve minimum means of automated ground control complex for these purposes.Currently, there is a completely developed theory of autonomous navigation based on astronomical positional gauges, which are used as onboard optical sensors of orientation and stabilization systems.To date, the differential navigation mode is, virtually, the only approach that can allow the olution of tasks in terms of increased accuracy, but with some restrictions.The implementation of differential mode of treatment is carried out through the creation of differential subsystems of the satellite navigation systems. These subsystems are usually divided into wide-range, regional and local ones.Analysis of ballistic aspects to implement discussed navigation technologies allowed us to identify constraints for improving accuracy to define

Surgical Navigation

DEFF Research Database (Denmark)

Azarmehr, Iman; Stokbro, Kasper; Bell, R. Bryan

2017-01-01

Purpose: This systematic review investigates the most common indications, treatments, and outcomes of surgical navigation (SN) published from 2010 to 2015. The evolution of SN and its application in oral and maxillofacial surgery have rapidly developed over recent years, and therapeutic indicatio...

The kidneys play a central role in the clearance of rhGH in rats

DEFF Research Database (Denmark)

Vestergaard, Bill; Thygesen, Peter; Kreilgaard, Mads

2016-01-01

at treatment of patients with growth hormone disorders. The purpose of this study was to investigate the relative importance of the kidneys in the clearance of rhGH. The study employed a newly validated nephrectomy rat model and a population based pharmacokinetic approach to assess renal clearance of rh...... that renal clearance plays a pivotal role in the elimination of rhGH in rats....

Computer Navigation-aided Resection of Sacral Chordomas

Directory of Open Access Journals (Sweden)

Yong-Kun Yang

2016-01-01

Full Text Available Background: Resection of sacral chordomas is challenging. The anatomy is complex, and there are often no bony landmarks to guide the resection. Achieving adequate surgical margins is, therefore, difficult, and the recurrence rate is high. Use of computer navigation may allow optimal preoperative planning and improve precision in tumor resection. The purpose of this study was to evaluate the safety and feasibility of computer navigation-aided resection of sacral chordomas. Methods: Between 2007 and 2013, a total of 26 patients with sacral chordoma underwent computer navigation-aided surgery were included and followed for a minimum of 18 months. There were 21 primary cases and 5 recurrent cases, with a mean age of 55.8 years old (range: 35-84 years old. Tumors were located above the level of the S3 neural foramen in 23 patients and below the level of the S3 neural foramen in 3 patients. Three-dimensional images were reconstructed with a computed tomography-based navigation system combined with the magnetic resonance images using the navigation software. Tumors were resected via a posterior approach assisted by the computer navigation. Mean follow-up was 38.6 months (range: 18-84 months. Results: Mean operative time was 307 min. Mean intraoperative blood loss was 3065 ml. For computer navigation, the mean registration deviation during surgery was 1.7 mm. There were 18 wide resections, 4 marginal resections, and 4 intralesional resections. All patients were alive at the final follow-up, with 2 (7.7% exhibiting tumor recurrence. The other 24 patients were tumor-free. The mean Musculoskeletal Tumor Society Score was 27.3 (range: 19-30. Conclusions: Computer-assisted navigation can be safely applied to the resection of the sacral chordomas, allowing execution of preoperative plans, and achieving good oncological outcomes. Nevertheless, this needs to be accomplished by surgeons with adequate experience and skill.

Clinical applications of virtual navigation bronchial intervention.

Science.gov (United States)

Kajiwara, Naohiro; Maehara, Sachio; Maeda, Junichi; Hagiwara, Masaru; Okano, Tetsuya; Kakihana, Masatoshi; Ohira, Tatsuo; Kawate, Norihiko; Ikeda, Norihiko

2018-01-01

In patients with bronchial tumors, we frequently consider endoscopic treatment as the first treatment of choice. All computed tomography (CT) must satisfy several conditions necessary to analyze images by Synapse Vincent. To select safer and more precise approaches for patients with bronchial tumors, we determined the indications and efficacy of virtual navigation intervention for the treatment of bronchial tumors. We examined the efficacy of virtual navigation bronchial intervention for the treatment of bronchial tumors located at a variety of sites in the tracheobronchial tree using a high-speed 3-dimensional (3D) image analysis system, Synapse Vincent. Constructed images can be utilized to decide on the simulation and interventional strategy as well as for navigation during interventional manipulation in two cases. Synapse Vincent was used to determine the optimal planning of virtual navigation bronchial intervention. Moreover, this system can detect tumor location and alsodepict surrounding tissues, quickly, accurately, and safely. The feasibility and safety of Synapse Vincent in performing useful preoperative simulation and navigation of surgical procedures can lead to safer, more precise, and less invasion for the patient, and makes it easy to construct an image, depending on the purpose, in 5-10 minutes using Synapse Vincent. Moreover, if the lesion is in the parenchyma or sub-bronchial lumen, it helps to perform simulation with virtual skeletal subtraction to estimate potential lesion movement. By using virtual navigation system for simulation, bronchial intervention was performed with no complications safely and precisely. Preoperative simulation using virtual navigation bronchial intervention reduces the surgeon's stress levels, particularly when highly skilled techniques are needed to operate on lesions. This task, including both preoperative simulation and intraoperative navigation, leads to greater safety and precision. These technological instruments

Low ground clearance vehicle detection and warning.

Science.gov (United States)

2015-06-01

A Low Ground Clearance Vehicle Detection : System (LGCVDS) determines if a commercial : motor vehicle can successfully clear a highwayrail : grade crossing and notifies the driver when : his or her vehicle cannot safely traverse the : crossing. That ...

The tribological behaviour of different clearance MOM hip joints with lubricants of physiological viscosities.

Science.gov (United States)

Hu, X Q; Wood, R J K; Taylor, A; Tuke, M A

2011-11-01

Clearance is one of the most influential parameters on the tribological performance of metal-on-metal (MOM) hip joints and its selection is a subject of considerable debate. The objective of this paper is to study the lubrication behaviour of different clearances for MOM hip joints within the range of human physiological and pathological fluid viscosities. The frictional torques developed by MOM hip joints with a 50 mm diameter were measured for both virgin surfaces and during a wear simulator test. Joints were manufactured with three different diametral clearances: 20, 100, and 200 microm. The fluid used for the friction measurements which contained different ratios of 25 percent newborn calf serum and carboxymethyl cellulose (CMC) with the obtained viscosities values ranging from 0.001 to 0.71 Pa s. The obtained results indicate that the frictional torque for the 20 microm clearance joint remains high over the whole range of the viscosity values. The frictional torque of the 100 microm clearance joint was low for the very low viscosity (0.001 Pa s) lubricant, but increased with increasing viscosity value. The frictional torque of the 200 microm clearance joint was high at very low viscosity levels, however, it reduced with increasing viscosity. It is concluded that a smaller clearance level can enhance the formation of an elastohydrodynamic lubrication (EHL) film, but this is at the cost of preventing fluid recovery between the bearing surfaces during the unloaded phase of walking. Larger clearance bearings allow a better recovery of lubricant during the unloaded phase, which is necessary for higher viscosity lubricants. The selection of the clearance value should therefore consider both the formation of the EHL film and the fluid recovery as a function of the physiological viscosity in order to get an optimal tribological performance for MOM hip joints. The application of either 25 per cent bovine serum or water in existing in vitro tribological study should

Requirements for e-Navigation Architectures

Directory of Open Access Journals (Sweden)

Axel Hahn

2016-12-01

Full Text Available Technology is changing the way of navigation. New technologies for communication and navigation can be found on virtually every vessel. System architectures define structure and cooperation of components and subsystems. IMO, IALA, costal authorities, technology provider and many more actually propose new architectures for e-Navigation. This paper looks at other transportation domains and technical as normative requirements for e-Navigation architectures. With the aim of identifying possible synergies in the research, development, certification and standardization, this paper sets out to compare requirements and approaches of these two domains with respect to safety and security aspects. Since from an autonomy perspective, the automotive domain has started earlier and therefore has achieved a higher degree of technical progress, we will start with an overview of the developments in this domain. After that, the paper discusses the requirements on automation and assistance systems in the maritime domain and gives an overview of the developments into this direction within the maritime domain. This then allows us to compare developments in both domains and to derive recommendations for further developments in the maritime domain at the end of this paper.

Mars rover local navigation and hazard avoidance

Science.gov (United States)

Wilcox, B. H.; Gennery, D. B.; Mishkin, A. H.

1989-01-01

A Mars rover sample return mission has been proposed for the late 1990's. Due to the long speed-of-light delays between earth and Mars, some autonomy on the rover is highly desirable. JPL has been conducting research in two possible modes of rover operation, Computer-Aided Remote Driving and Semiautonomous Navigation. A recently-completed research program used a half-scale testbed vehicle to explore several of the concepts in semiautonomous navigation. A new, full-scale vehicle with all computational and power resources on-board will be used in the coming year to demonstrate relatively fast semiautonomous navigation. The computational and power requirements for Mars rover local navigation and hazard avoidance are discussed.

Proficiency testing criteria for clearance level in solid waste gamma measurement in Taiwan.

Science.gov (United States)

Chen, Chun-Liang; Wang, Jeng-Jong; Chiu, Huang-Sheng

2013-11-01

To guarantee the measurement quality for clearance level in solid waste material, the Institute of Nuclear Energy Research (INER) established the criteria for proficiency testing of clearance level measurement. INER and the Taiwan Accreditation Foundation (TAF) organized the Technique Committee Meeting twice to discuss these criteria in 2011. The participating laboratories must completely conform to the ISO/IEC 17025, and they also must meet the requirements of the criteria. According to the criteria, the participating laboratories analyzed the minimum detectable amount (MDA) and that should be less than 20% of the clearance level (AMDA) given in the Atomic Energy Council's (AEC) "Regulations on Clearance Level for Radioactive Waste Management". The testing results should conform to the deviation and traceability requirements. Copyright © 2013 Elsevier Ltd. All rights reserved.

Not All Children with Cystic Fibrosis Have Abnormal Esophageal Neutralization during Chemical Clearance of Acid Reflux.

Science.gov (United States)

Woodley, Frederick W; Moore-Clingenpeel, Melissa; Machado, Rodrigo Strehl; Nemastil, Christopher J; Jadcherla, Sudarshan R; Hayes, Don; Kopp, Benjamin T; Kaul, Ajay; Di Lorenzo, Carlo; Mousa, Hayat

2017-09-01

Acid neutralization during chemical clearance is significantly prolonged in children with cystic fibrosis, compared to symptomatic children without cystic fibrosis. The absence of available reference values impeded identification of abnormal findings within individual patients with and without cystic fibrosis. The present study aimed to test the hypothesis that significantly more children with cystic fibrosis have acid neutralization durations during chemical clearance that fall outside the physiological range. Published reference value for acid neutralization duration during chemical clearance (determined using combined impedance/pH monitoring) was used to assess esophageal acid neutralization efficiency during chemical clearance in 16 children with cystic fibrosis (3 to chemical clearance exceeded the upper end of the physiological range in 9 of 16 (56.3%) children with and in 3 of 16 (18.8%) children without cystic fibrosis ( p =0.0412). The likelihood ratio for duration indicated that children with cystic fibrosis are 2.1-times more likely to have abnormal acid neutralization during chemical clearance, and children with abnormal acid neutralization during chemical clearance are 1.5-times more likely to have cystic fibrosis. Significantly more (but not all) children with cystic fibrosis have abnormally prolonged esophageal clearance of acid. Children with cystic fibrosis are more likely to have abnormal acid neutralization during chemical clearance. Additional studies involving larger sample sizes are needed to address the importance of genotype, esophageal motility, composition and volume of saliva, and gastric acidity on acid neutralization efficiency in cystic fibrosis children.

Technetium-99m mercaptoacetyltriglycine clearance values in children with minimal renal disease: can a normal range be determined?

International Nuclear Information System (INIS)

Meyer, G.; Hahn, K.; Piepsz, A.; Kolinska, J.; Lepej, J.; Sixt, R.

1998-01-01

Use of technetium-99m labelled mercaptoacetyltriglycine ( 99m Tc-MAG3) simplifies and improves the quantification of renal clearance in children by virtue of its permanent availability, good imaging properties and low radiation exposure. Due to the lack of reference values for 99m Tc-MAG3 clearance in children, the Paediatric Task Group of the EANM initiated a multicentre study to evaluate 99m Tc-MAG3 clearance values in children with minimal renal disease. One hundred and twenty-five children aged between 12 months and 17 years, classified as renally healthy using defined diagnostic criteria, were included in the study. 99m Tc-MAG3 clearance was calculated using an algorithm on the basis of a single blood sample taken at any time between 30 and 40 min after tracer injection. In addition, the absolute 99m -Tc-MAG3 clearance values were normalized to body surface area. For further evaluation the children were classified into several groups according to age. There was a continuous increase in non-corrected 99m Tc-MAG3 clearance values from the age of 1 year up to the age of 17 years (mean value 8 years: 208±66 ml/min). Normal clearance values for adults were achieved by the age of 8 years. Analysis of the relationship between non-corrected clearance and age yielded a correlation coefficient of r=0.7. When these absolute clearance values were normalized to body surface area, we found nearly constant clearance values for all age groups, with a mean clearance value of 315±114 ml/min x 1.73 m 2 . The correlation coefficient for the relationship between normalized clearance and age was r=0.28. In conclusion, the clearance of 99m Tc-MAG3 increases continuously throughout childhood into adolescence due to the maturation and growth of the kidney. After normalization of the absolute clearance to body surface area, no correlation between clearance and age could be proven. (orig.)

Dextran fractional clearance studies in acute dengue infection.

Directory of Open Access Journals (Sweden)

Julie Nguyen-Pouplin

2011-08-01

Full Text Available Although increased capillary permeability is the major clinical feature associated with severe dengue infections the mechanisms underlying this phenomenon remain unclear. Dextran clearance methodology has been used to investigate the molecular sieving properties of the microvasculature in clinical situations associated with altered permeability, including during pregnancy and in various renal disorders. In order to better understand the characteristics of the vascular leak associated with dengue we undertook formal dextran clearance studies in Vietnamese dengue patients and healthy volunteers.We carried out serial clearance studies in 15 young adult males with acute dengue and evidence of vascular leakage a during the phase of maximal leakage and b one and three months later, as well as in 16 healthy control subjects. Interestingly we found no difference in the clearance profiles of neutral dextran solutions among the dengue patients at any time-point or in comparison to the healthy volunteers.The surface glycocalyx layer, a fibre-matrix of proteoglycans, glycosaminoglycans, and plasma proteins, forms a complex with the underlying endothelial cells to regulate plasma volume within circumscribed limits. It is likely that during dengue infections loss of plasma proteins from this layer alters the permeability characteristics of the complex; physical and/or electrostatic interactions between the dextran molecules and the glycocalyx structure may temporarily restore normal function, rendering the technique unsuitable for assessing permeability in these patients. The implications for resuscitation of patients with dengue shock syndrome (DSS are potentially important. It is possible that continuous low-dose infusions of dextran may help to stabilize the permeability barrier in patients with profound or refractory shock, reducing the need for repeated boluses, limiting the total colloid volume required. Formal clinical studies should help to assess

Surface code—biophysical signals for apoptotic cell clearance

International Nuclear Information System (INIS)

Biermann, Mona; Maueröder, Christian; Brauner, Jan M; Chaurio, Ricardo; Herrmann, Martin; Muñoz, Luis E; Janko, Christina

2013-01-01

Apoptotic cell death and the clearance of dying cells play an important and physiological role in embryonic development and normal tissue turnover. In contrast to necrosis, apoptosis proceeds in an anti-inflammatory manner. It is orchestrated by the timed release and/or exposure of so-called ‘find-me’, ‘eat me’ and ‘tolerate me’ signals. Mononuclear phagocytes are attracted by various ‘find-me’ signals, including proteins, nucleotides, and phospholipids released by the dying cell, whereas the involvement of granulocytes is prevented via ‘stay away’ signals. The exposure of anionic phospholipids like phosphatidylserine (PS) by apoptotic cells on the outer leaflet of the plasma membrane is one of the main ‘eat me’ signals. PS is recognized by a number of innate receptors as well as by soluble bridging molecules on the surface of phagocytes. Importantly, phagocytes are able to discriminate between viable and apoptotic cells both exposing PS. Due to cytoskeleton remodeling PS has a higher lateral mobility on the surfaces of apoptotic cells thereby promoting receptor clustering on the phagocyte. PS not only plays an important role in the engulfment process, but also acts as ‘tolerate me’ signal inducing the release of anti-inflammatory cytokines by phagocytes. An efficient and fast clearance of apoptotic cells is required to prevent secondary necrosis and leakage of intracellular danger signals into the surrounding tissue. Failure or prolongation of the clearance process leads to the release of intracellular antigens into the periphery provoking inflammation and development of systemic inflammatory autoimmune disease like systemic lupus erythematosus. Here we review the current findings concerning apoptosis-inducing pathways, important players of apoptotic cell recognition and clearance as well as the role of membrane remodeling in the engulfment of apoptotic cells by phagocytes. (paper)

Trend of research and development on clearance system for CBRNE agents

International Nuclear Information System (INIS)

Ishihara, Masayuki; Fujita, Masanori; Ishida, Natsuko; Hattori, Hidemi; Tachibana, Shoich; Nakamura, Shingo; Kanatani, Yasuhiro

2013-01-01

In a field of disaster for a wide variety of Chemical, Biological, Radiological, Nuclear, Explosive (CBRNE) agents which are harmful and deadly poisonous, it is crucial to effectively clear those agents for prevention of expanded damages and retrieval from damage. The clearance technologies in the CBRNE disaster field require to be safe for human body and to be friendly for the environments. In addition, they need scientific data-based evidences for their effectiveness and safety. The aim of this article is to view the trend of research on clearances of N, B and c agents in terms of rapidity, simplicity and economic rationality, and to deliberate on effective clearance system using adequate equipments and materials for detoxification, decomposition and removal of each contamination. (author)

An Effective Terrain Aided Navigation for Low-Cost Autonomous Underwater Vehicles.

Science.gov (United States)

Zhou, Ling; Cheng, Xianghong; Zhu, Yixian; Dai, Chenxi; Fu, Jinbo

2017-03-25

Terrain-aided navigation is a potentially powerful solution for obtaining submerged position fixes for autonomous underwater vehicles. The application of terrain-aided navigation with high-accuracy inertial navigation systems has demonstrated meter-level navigation accuracy in sea trials. However, available sensors may be limited depending on the type of the mission. Such limitations, especially for low-grade navigation sensors, not only degrade the accuracy of traditional navigation systems, but further impact the ability to successfully employ terrain-aided navigation. To address this problem, a tightly-coupled navigation is presented to successfully estimate the critical sensor errors by incorporating raw sensor data directly into an augmented navigation system. Furthermore, three-dimensional distance errors are calculated, providing measurement updates through the particle filter for absolute and bounded position error. The development of the terrain aided navigation system is elaborated for a vehicle equipped with a non-inertial-grade strapdown inertial navigation system, a 4-beam Doppler Velocity Log range sensor and a sonar altimeter. Using experimental data for navigation performance evaluation in areas with different terrain characteristics, the experiment results further show that the proposed method can be successfully applied to the low-cost AUVs and significantly improves navigation performance.

Rate-Based Model Predictive Control of Turbofan Engine Clearance

Science.gov (United States)

DeCastro, Jonathan A.

2006-01-01

An innovative model predictive control strategy is developed for control of nonlinear aircraft propulsion systems and sub-systems. At the heart of the controller is a rate-based linear parameter-varying model that propagates the state derivatives across the prediction horizon, extending prediction fidelity to transient regimes where conventional models begin to lose validity. The new control law is applied to a demanding active clearance control application, where the objectives are to tightly regulate blade tip clearances and also anticipate and avoid detrimental blade-shroud rub occurrences by optimally maintaining a predefined minimum clearance. Simulation results verify that the rate-based controller is capable of satisfying the objectives during realistic flight scenarios where both a conventional Jacobian-based model predictive control law and an unconstrained linear-quadratic optimal controller are incapable of doing so. The controller is evaluated using a variety of different actuators, illustrating the efficacy and versatility of the control approach. It is concluded that the new strategy has promise for this and other nonlinear aerospace applications that place high importance on the attainment of control objectives during transient regimes.

A parameters optimization method for planar joint clearance model and its application for dynamics simulation of reciprocating compressor

Science.gov (United States)

Hai-yang, Zhao; Min-qiang, Xu; Jin-dong, Wang; Yong-bo, Li

2015-05-01

In order to improve the accuracy of dynamics response simulation for mechanism with joint clearance, a parameter optimization method for planar joint clearance contact force model was presented in this paper, and the optimized parameters were applied to the dynamics response simulation for mechanism with oversized joint clearance fault. By studying the effect of increased clearance on the parameters of joint clearance contact force model, the relation of model parameters between different clearances was concluded. Then the dynamic equation of a two-stage reciprocating compressor with four joint clearances was developed using Lagrange method, and a multi-body dynamic model built in ADAMS software was used to solve this equation. To obtain a simulated dynamic response much closer to that of experimental tests, the parameters of joint clearance model, instead of using the designed values, were optimized by genetic algorithms approach. Finally, the optimized parameters were applied to simulate the dynamics response of model with oversized joint clearance fault according to the concluded parameter relation. The dynamics response of experimental test verified the effectiveness of this application.

Navigation System of Marks Areas - USACE IENC

Data.gov (United States)

Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

Cerebrospinal fluid clearance in Alzheimer disease measured with dynamic PET

DEFF Research Database (Denmark)

De Leon, Mony J.; Li, Yi; Okamura, Nobuyuki

2017-01-01

Evidence supporting the hypothesis that reduced cerebrospinal fluid (CSF) clearance is involved in the pathophysiology of Alzheimer disease (AD) comes primarily from rodent models. However, unlike rodents, in which predominant extracranial CSF egress is via olfactory nerves traversing the cribrif......Evidence supporting the hypothesis that reduced cerebrospinal fluid (CSF) clearance is involved in the pathophysiology of Alzheimer disease (AD) comes primarily from rodent models. However, unlike rodents, in which predominant extracranial CSF egress is via olfactory nerves traversing...

Influence of tip clearance on flow behavior and noise generation of centrifugal compressors in near-surge conditions

International Nuclear Information System (INIS)

Galindo, J.; Tiseira, A.; Navarro, R.; López, M.A.

2015-01-01

Highlights: • Centrifugal compressor aeroacoustics sensitivity to tip clearance is investigated. • 3 different clearance ratios are set in accordance to expected operating values. • Pressure spectra do not depend on tip clearance ratio in near-surge conditions. • DES performs better than URANS in predicting compressor acoustic signature. • Flow field observation reveals that tip clearance is immersed in rotating backflow. - Abstract: CFD has become an essential tool for researchers to analyze centrifugal compressors. Tip leakage flow is usually considered one of the main mechanisms that dictate compressor flow field and stability. However, it is a common practice to rely on CAD tip clearance, even though the gap between blades and shroud changes when compressor is running. In this paper, sensitivity of centrifugal compressor flow field and noise prediction to tip clearance ratio is investigated. 3D CFD simulations are performed with three different tip clearance ratios in accordance to expected operating values, extracted from shaft motion measurements and FEM predictions of temperature and rotational deformation. Near-surge operating conditions are simulated with URANS and DES. DES shows superior performance for acoustic predictions. Cases with reduced tip clearance present higher pressure ratio and isentropic efficiency, but no significant changes in compressor acoustic signature are found when varying clearance. In this working point, tip clearance is immersed in a region of strongly swirling backflow. Therefore, tip leakage cannot establish any coherent noise source mechanism

Decreased insulin clearance in individuals with elevated 1-h post-load plasma glucose levels.

Directory of Open Access Journals (Sweden)

Maria Adelaide Marini

Full Text Available Reduced insulin clearance has been shown to predict the development of type 2 diabetes. Recently, it has been suggested that plasma glucose concentrations ≥ 8.6 mmol/l (155 mg/dl at 1 h during an oral glucose tolerance test (OGTT can identify individuals at high risk for type 2 diabetes among those who have normal glucose tolerance (NGT 1 h-high. The aim of this study was to examine whether NGT 1 h-high have a decrease in insulin clearance, as compared with NGT individuals with 1-h post-load glucose <8.6 mmol/l (l (155 mg/dl, NGT 1 h-low. To this end, 438 non-diabetic White individuals were subjected to OGTT and euglycemic-hyperinsulinemic clamp to evaluate insulin clearance and insulin sensitivity. As compared with NGT 1 h-low individuals, NGT 1 h-high had significantly higher 1-h and 2-h post-load plasma glucose and 2-h insulin levels as well as higher fasting glucose and insulin levels. NGT 1 h-high exhibited also a significant decrease in both insulin sensitivity (P<0.0001 and insulin clearance (P = 0.006 after adjusting for age, gender, adiposity measures, and insulin sensitivity. The differences in insulin clearance remained significant after adjustment for fasting glucose (P = 0.02 in addition to gender, age, and BMI. In univariate analyses adjusted for gender and age, insulin clearance was inversely correlated with body weight, body mass index, waist, fat mass, 1-h and 2-h post-load glucose levels, fasting, 1-h and 2-h post-load insulin levels, and insulin-stimulated glucose disposal. In conclusion, our data show that NGT 1 h-high have a reduction in insulin clearance as compared with NGT 1 h-low individuals; this suggests that impaired insulin clearance may contribute to sustained fasting and post-meal hyperinsulinemia.

Navigating in higher education

DEFF Research Database (Denmark)

Thingholm, Hanne Balsby; Reimer, David; Keiding, Tina Bering

Denne rapport er skrevet på baggrund af spørgeskemaundersøgelsen – Navigating in Higher Education (NiHE) – der rummer besvarelser fra 1410 bachelorstuderende og 283 undervisere fordelt på ni uddannelser fra Aarhus Universitet: Uddannelsesvidenskab, Historie, Nordisk sprog og litteratur, Informati......Denne rapport er skrevet på baggrund af spørgeskemaundersøgelsen – Navigating in Higher Education (NiHE) – der rummer besvarelser fra 1410 bachelorstuderende og 283 undervisere fordelt på ni uddannelser fra Aarhus Universitet: Uddannelsesvidenskab, Historie, Nordisk sprog og litteratur...

PRIVATE GRAPHS – ACCESS RIGHTS ON GRAPHS FOR SEAMLESS NAVIGATION

Directory of Open Access Journals (Sweden)

W. Dorner

2016-06-01

Full Text Available After the success of GNSS (Global Navigational Satellite Systems and navigation services for public streets, indoor seems to be the next big development in navigational services, relying on RTLS – Real Time Locating Services (e.g. WIFI and allowing seamless navigation. In contrast to navigation and routing services on public streets, seamless navigation will cause an additional challenge: how to make routing data accessible to defined users or restrict access rights for defined areas or only to parts of the graph to a defined user group? The paper will present case studies and data from literature, where seamless and especially indoor navigation solutions are presented (hospitals, industrial complexes, building sites, but the problem of restricted access rights was only touched from a real world, but not a technical perspective. The analysis of case studies will show, that the objective of navigation and the different target groups for navigation solutions will demand well defined access rights and require solutions, how to make only parts of a graph to a user or application available to solve a navigational task. The paper will therefore introduce the concept of private graphs, which is defined as a graph for navigational purposes covering the street, road or floor network of an area behind a public street and suggest different approaches how to make graph data for navigational purposes available considering access rights and data protection, privacy and security issues as well.

THE ROLE OF NAVIGATIONAL AIDS IN FLIGHT SAFETY MANAGEMENT WITHIN ICAO GLOBAL AIR NAVIGATION PLAN

Directory of Open Access Journals (Sweden)

Vadim V. Vurobyov

2017-01-01

Full Text Available The development of the global civil aviation is provided on the basis of the ICAO Communication and Surveillance/Air Traffic Management Concept, which has determined the basic strategy for further commercial flight management effectiveness improvement. On the basis of this concept a Global Air Navigation Plan has been developed by ICAO recently. The core strategies of CNS/ATM concept were specified and combined into so-called blocks. Thus the term Global Aviation System block upgrade has been introduced. At the same time, GANP states that the introduction of new procedures and flight management systems will inevitably affect flight safety. Accordingly, there is a task of flight safety management level maintaining, or even increasing within the Global Air Navigation Plan implementation. Various air navigational aids play a significant role in the process as they are directly associated with the new systems and structures introduction.This breeds the new global challenge of flight safety management level change assessment during the introduction of new procedures and systems connected with the use of both navigational aids and instruments. Some aspects of this problem solution are covered in the article.

The Swedish nuclear industry way to approach higher demands on characterisation prior to clearance

International Nuclear Information System (INIS)

Larsson, Arne; Hellsten, Erik; Berglund, Malin; Larsson, Lars

2012-01-01

The Swedish Radiation Safety Authority (SSM) has introduced new regulations for clearance SSMFS 2011:2 'Regulations concerning clearance of material, rooms, buildings and soil from activities with ionizing radiation'. The new regulations came into force January 1, 2012. Compared to the previous regulations these new regulations have a broader scope and have introduced new conditions such as nuclide specific clearance levels. Clearance is practiced to reduce the amount of radioactive waste generated. Cleared material can be reused, recycled or if these two possibilities are not available, disposed of as conventional waste. To be able to meet the requirements for clearance the Swedish nuclear industry has jointly developed guidance for clearance in the form of a handbook and a training course covering the competence requirements in the new regulations. The handbook was developed by a team of representatives from the Swedish nuclear license holders managed by Studsvik on behalf of Swedish Nuclear Fuel and Waste Management Company (SKB). The training program was developed in co-operation between Nuclear Safety and training Company (KSU) and Studsvik on behalf of the Swedish nuclear license holders. A major challenge in the adoption to the new regulations is how to provide robust yet cost effective characterisation data. This is especially difficult for mobile materials and equipment which cannot be fully tracked but also for other materials and areas where the nuclide fingerprint has varied over the years. To be able to deal with these issues a lot of attention has to be paid to the historical inventory records and traceability in the clearance process. Materials, rooms and buildings have been divided in four categories with different requirements on frequency and requirements of measurements. The categories are named 'extremely small risk', 'small risk', 'risk' and 'known contamination above clearance levels'. The two day training course is dived into seven parts

GPS Navigation and Tracking Device

Directory of Open Access Journals (Sweden)

Yahya Salameh Khraisat

2011-10-01

Full Text Available Since the introduction of GPS Navigation systems in the marketplace, consumers and businesses have been coming up with innovative ways to use the technology in their everyday life. GPS Navigation and Tracking systems keep us from getting lost when we are in strange locations, they monitor children when they are away from home, keep track of business vehicles and can even let us know where a philandering partner is at all times. Because of this we attend to build a GPS tracking device to solve the mentioned problems. Our work consists of the GPS module that collects data from satellites and calculates the position information before transmitting them to the user’s PC (of Navigation system or observers (of Tracking System using wireless technology (GSM.

Quantitative assessment of caffeine partial clearances in man.

Science.gov (United States)

Lelo, A; Miners, J O; Robson, R A; Birkett, D J

1986-01-01

Five subjects who participated in an earlier study (Lelo et al., 1986b) of the comparative pharmacokinetics of caffeine (CA) and its primary monodemethylated metabolites paraxanthine (PX), theobromine (TB) and theophylline (TP) were administered CA to steady-state. Using areas under the plasma concentration-time curves for each of the dimethylxanthines derived from CA in the steady-state study and individual plasma clearances of PX, TB and TP determined in the previous study, the fractional conversion of CA to PX, TB and TP and the individual partial clearances of CA have been defined. The mean (+/- s.d.) fractional conversion of CA to PX, TB and TP was 79.6 +/- 21.0%, 10.8 +/- 2.4% and 3.7 +/- 1.3%, respectively. When only demethylation pathways are considered PX, TB and TP accounted for 83.9 +/- 5.4%, 12.1 +/- 4.1% and 4.0 +/- 1.4%, respectively of the CA demethylations. The mean partial clearance of CA to PX was approximately 8-fold and 23-fold greater than those to TB and TP respectively. These data confirm earlier reports that PX is the major metabolite of CA in humans but suggest that PX formation is quantitatively more important than previously believed. PMID:3756066

A Qualitative Approach to Mobile Robot Navigation Using RFID

International Nuclear Information System (INIS)

Hossain, M; Rashid, M M; Bhuiyan, M M I; Ahmed, S; Akhtaruzzaman, M

2013-01-01

Radio Frequency Identification (RFID) system allows automatic identification of items with RFID tags using radio-waves. As the RFID tag has its unique identification number, it is also possible to detect a specific region where the RFID tag lies in. Recently it is widely been used in mobile robot navigation, localization, and mapping both in indoor and outdoor environment. This paper represents a navigation strategy for autonomous mobile robot using passive RFID system. Conventional approaches, such as landmark or dead-reckoning with excessive number of sensors, have complexities in establishing the navigation and localization process. The proposed method satisfies less complexity in navigation strategy as well as estimation of not only the position but also the orientation of the autonomous robot. In this research, polar coordinate system is adopted on the navigation surface where RFID tags are places in a grid with constant displacements. This paper also presents the performance comparisons among various grid architectures through simulation to establish a better solution of the navigation system. In addition, some stationary obstacles are introduced in the navigation environment to satisfy the viability of the navigation process of the autonomous mobile robot

Decision Assessment of Clearance Level on Radioactive Waste Management

International Nuclear Information System (INIS)

Zainus Salimin; Gunandjar

2007-01-01

Radioactive waste on the safe level activity containing very small radioactive material gives small radiology influence to the human, it is not necessary to control by regulatory body. The radioactive waste on the safe level activity is safe to release as the common waste. For exemption of the control, it is required the safe activity level limits in which the value of clearance level is fulfilled by regulatory body, however until now it is not decided yet. The exemption decision is obtained if its activity is lower than or same with clearance level based on the annual effective dose receiving by public on the value is lower than or same with 0,01 mSv. The exposure pathways of radioactive waste to the human have important role for determination of clearance level. The decision assessment of clearance level on the radioactive waste management has been done by analysis of radioactive exposure pathways to the human for activities of the disposal and the recycle of solid wastes, also the release of liquid and gas effluent. For solid waste disposal, the exposure pathway was evaluated since the transportation of packed waste from the treatment facility to the disposal facility and during its operation. Exposure pathways for solid waste recycle consist of the pathways for handling and transportation of cleared material to the recycling facility, the fabrication and the utilization of its product. Exposure pathways for liquid and gas releases occur since its releases to the environment up to the human (public) by specific traffic lane. (author)

Navigation in musculoskeletal oncology: An overview

Directory of Open Access Journals (Sweden)

Guy Vernon Morris

2018-01-01

Full Text Available Navigation in surgery has increasingly become more commonplace. The use of this technological advancement has enabled ever more complex and detailed surgery to be performed to the benefit of surgeons and patients alike. This is particularly so when applying the use of navigation within the field of orthopedic oncology. The developments in computer processing power coupled with the improvements in scanning technologies have permitted the incorporation of navigational procedures into day-to-day practice. A comprehensive search of PubMed using the search terms “navigation”, “orthopaedic” and “oncology” yielded 97 results. After filtering for English language papers, excluding spinal surgery and review articles, this resulted in 38 clinical studies and case reports. These were analyzed in detail by the authors (GM and JS and the most relevant papers reviewed. We have sought to provide an overview of the main types of navigation systems currently available within orthopedic oncology and to assess some of the evidence behind its use.

Bromsulphalein (BSP) clearance in ageing rats

NARCIS (Netherlands)

Hollander, C.F.; Leeuw-Israel, F.R. de; Arp-Neefjes, J.M.

1968-01-01

Liver function in ageing rats was studied, using the bromsulphalein (BSP) clearance test. The test was done on ultramicro scale. This made it possible to repeat the test several times in the same animal and to start a longitudinal study. In 3-month-old rats the BSP retentions, measured 15, 30 and 45

Non-destructive clearance measuring in closed joints

International Nuclear Information System (INIS)

Doucelance, C.; Manaranche, J.C.

1976-01-01

Two methods for clearance measuring in closed joints are described. The first one is based on the mechanical impedance concept, while the other one requires a shock test on shaker. Both are illustrated with an example of application [fr

Hyperinsulinism and polycystic ovary syndrome (PCOS): role of insulin clearance.

Science.gov (United States)

Amato, M C; Vesco, R; Vigneri, E; Ciresi, A; Giordano, C

2015-12-01

Insulin resistance and compensatory hyperinsulinism are the predominant metabolic defects in polycystic ovary syndrome (PCOS). However, hyperinsulinism, as well as being compensatory, can also express a condition of reduced insulin clearance. Our aim was to evaluate the differences in insulin action and metabolism between women with PCOS (with normal glucose tolerance) and age- and BMI-matched women with prediabetes (without hyperandrogenism and ovulatory disorders). 22 women with PCOS and 21 age/BMI-matched women with prediabetes were subjected to a Hyperinsulinemic-euglycemic clamp and an Oral Glucose tolerance Test (OGTT). Insulin sensitivity was assessed by the glucose infusion rate during clamp (M value); insulin secretion by Insulinogenic index, Oral Disposition Index (DIo) and AUC(2h-insulin) during OGTT; and insulin clearance by the metabolic clearance rate of insulin (MCRI) during clamp. Women with PCOS showed significantly higher levels of AUC(2h-insulin) (p PCOS [420 (IQR 227-588) vs. 743 (IQR 597-888) ml m(-2) min(-1): p PCOS group, a strong independent inverse correlation was only observed between MCRI and AUC(2h-insulin) (PCOS: β:-0.878; p PCOS there is peripheral insulin sensitivity similar to that of women with prediabetes. What sets PCOS apart is the hyperinsulinism, today still simplistically defined "compensatory"; actually this is mainly related to decreased insulin clearance whose specific causes and dynamics have yet to be clarified.

133 xenon muscle clearance as a test parameter in the diagnosis of peripheral diabetic angiopathies

International Nuclear Information System (INIS)

Kuhlmann, J.E.

1980-01-01

In 100 patients with manifest diabetes mellitus the irrigation in both legs at rest and in radioactive hyperemia after ischemic muscle work was measured by means of the 133-xenon muscle clearance. The clearance values measured ranged between 0.8 and 3.5 ml/100 g/60 s at rest and between 3.3 and 40.0 ml/100 gl/60 s during radioactive hyperemia. In 96 pc of the probands the irrigation of the legs was impaired. For the relation between glucose level and irrigation at rest a significant negative correlation was found. The difference between the clearance values for the right and left lower extremity was significant. For the relation between glucose level and reactive hyperemia, too, a significant negative correlation was found. The difference between the clearance values for the right and left lower extremities was significant. The measurement of the irrigation at rest showed no significant correlation between the period of manifestation of the diabetes and the clearance values. By contrast, the irrigation values during reactive hyperemia were shown to be in significantly negative correlation to the duration of the diabetes. No connection was found between the frequency of diabetic gangrene and impaired irrigation at rest. By contrast, there was a relation between decreasing hyperemia values and increased frequency of gangrene. A collection of case histories shows how the measuring results of the xenon clearance fit into the overall clinical picture. A comparison of xenon clearance with other methods of irrigation measurement confirmed obvious advantages of xenon clearance for the detection of diabetic microangiopathies. (orig./MG) [de

Serial thallium-201 imaging after dipyridamole for coronary disease detection: quantitative analysis using myocardial clearance

International Nuclear Information System (INIS)

Okada, R.D.; Dai, Y.H.; Boucher, C.A.; Pohost, G.M.

1984-01-01

After dipyridamole, canine studies have demonstrated a slower rate of myocardial thallium-201 clearance from zones distal to a coronary artery stenosis compared to normal zones. To determine if criteria based on canine myocardial thallium-201 clearance rates could be applied clinically, 40 patients with and 26 patients without coronary artery disease (CAD) had serial thallium-201 images obtained for 2 to 5 hours after dipyridamole. Regions of interest were manually placed over six left ventricular segments in two projections for each of three imaging times. The myocardial thallium-201 clearance rate was calculated for each of the six segments and, using the clearance rate criterion found in canine studies, was considered abnormal if less than 6.5%/hr. Using this criterion alone, 22 of 26 patients (85%) without CAD had normal and 30 of 40 patients (75%) with CAD had abnormal myocardial thallium-201 clearance rates. A quantitative analysis of regional inhomogeneity in tracer distribution (normal was greater than or equal to 25% difference between segments) was negative in 24 of 26 patients (92%) without CAD and positive in 20 of 40 patients (50%) with CAD. When both clearance rate and regional inhomogeneity were considered, 21 of 26 patients (81%) without CAD had negative and 36 of 40 patients (90%) with CAD had positive results. Thus, post-dipyridamole myocardial clearance rate criteria derived from canine studies can be applied to clinical thallium imaging. Quantitative analysis of serial thallium-201 images after dipyridamole is optimized by using myocardial thallium-201 clearance rates. Such an approach is independent of regional inhomogeneities in tracer distribution

A navigator-based rigid body motion correction for magnetic resonance imaging

International Nuclear Information System (INIS)

Ullisch, Marcus Goerge

2012-01-01

A novel three-dimensional navigator k-space trajectory for rigid body motion detection for Magnetic Resonance Imaging (MRI) - the Lissajous navigator - was developed and quantitatively compared to the existing spherical navigator trajectory [1]. The spherical navigator cannot sample the complete spherical surface due to slew rate limitations of the scanner hardware. By utilizing a two dimensional Lissajous figure which is projected onto the spherical surface, the Lissajous navigator overcomes this limitation. The complete sampling of the sphere consequently leads to rotation estimates with higher and more isotropic accuracy. Simulations and phantom measurements were performed for both navigators. Both simulations and measurements show a significantly higher overall accuracy of the Lissajous navigator and a higher isotropy of the rotation estimates. Measured under identical conditions with identical postprocessing, the measured mean absolute error of the rotation estimates for the Lissajous navigator was 38% lower (0.3 ) than for the spherical navigator (0.5 ). The maximum error of the Lissajous navigator was reduced by 48% relative to the spherical navigator. The Lissajous navigator delivers higher accuracy of rotation estimation and a higher degree of isotropy than the spherical navigator with no evident drawbacks; these are two decisive advantages, especially for high-resolution anatomical imaging.

A navigator-based rigid body motion correction for magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Ullisch, Marcus Goerge

2012-01-24

A novel three-dimensional navigator k-space trajectory for rigid body motion detection for Magnetic Resonance Imaging (MRI) - the Lissajous navigator - was developed and quantitatively compared to the existing spherical navigator trajectory [1]. The spherical navigator cannot sample the complete spherical surface due to slew rate limitations of the scanner hardware. By utilizing a two dimensional Lissajous figure which is projected onto the spherical surface, the Lissajous navigator overcomes this limitation. The complete sampling of the sphere consequently leads to rotation estimates with higher and more isotropic accuracy. Simulations and phantom measurements were performed for both navigators. Both simulations and measurements show a significantly higher overall accuracy of the Lissajous navigator and a higher isotropy of the rotation estimates. Measured under identical conditions with identical postprocessing, the measured mean absolute error of the rotation estimates for the Lissajous navigator was 38% lower (0.3 ) than for the spherical navigator (0.5 ). The maximum error of the Lissajous navigator was reduced by 48% relative to the spherical navigator. The Lissajous navigator delivers higher accuracy of rotation estimation and a higher degree of isotropy than the spherical navigator with no evident drawbacks; these are two decisive advantages, especially for high-resolution anatomical imaging.

TAM receptors in apoptotic cell clearance, autoimmunity, and cancer.

Science.gov (United States)

Nguyen, Khanh-Quynh; Tsou, Wen-I; Kotenko, Sergei; Birge, Raymond B

2013-08-01

Receptor tyrosine kinases, Tyro-3, Axl and Mer, collectively designated as TAM, are involved in the clearance of apoptotic cells. TAM ligands, Gas6 and Protein S, bind to the surfaces of apoptotic cells, and at the same time, interact directly with TAM expressed on phagocytes, impacting the engulfment and clearance of apoptotic cells and debris. The well-tuned and balanced actions of TAM may affect a variety of human pathologies including autoimmunity, retinal degeneration, and cancer. This article emphasizes some of the emerging findings and mechanistic insights into TAM functions that are clinically relevant and possibly therapeutically targeted.

Clearance of buildings for demolition: ways to clearance on the standing structure for covered surfaces and inaccessible areas

International Nuclear Information System (INIS)

Thraenert, S.; Riemann, T.

2014-01-01

In general terms, the TUV NORD Nuclear services encompass safety assessments, design reviews, documentation re-views and inspections. They reflect the full scope of a technical service provider in the nuclear field. In the domestic market, these services are provided for the regulator, whereas in the international market any party involved in a nuclear project is a potential customer of TUV NORD Nuclear. This implies that TUV NORD Nuclear is offering consultancy, engineering and inspection services. Regarding the clearance of buildings for demolition, there are two different possible ways for the radiological characterization. The first option is a characterization on the standing structure before demolition and the second option is the characterization of the building rubble after demolition. According to the German Radiation Protection Ordinance, buildings of decommissioned nuclear sites have to be preferentially cleared on the standing structure. If compliance with the surface specific clearance levels is achieved on the standing structure, usually the cleared buildings can be demolished and the resulting rubble may be used without any further radiological considerations. In the case of the former nuclear power plant Wuergassen the majority of the building rubble is scheduled to stay on site to serve as backfill for the building pit. As such a scenario was not considered in the radiological considerations of, e.g., the German Radiation Protection Ordinance, an additional dose calculation was carried out for Wuergassen NPP basing on its radiological characteristics to directly prove compliance with the de-minimis-concept. The radiation controlled area (RCA) of Wuergassen NPP comprises an area of about 140.000 m 2 . This area is more or less easily accessible to characterization and decontamination using, if necessary, scaffoldings or lifting platforms. Up to the beginning of 2013, compliance with the surface specific clearance levels was verified on the standing

Lithium clearance and renal tubular sodium handling during acute and long-term nifedipine treatment in essential hypertension

DEFF Research Database (Denmark)

Bruun, N E; Ibsen, H; Skøtt, P

1988-01-01

1. In two separate studies the lithium clearance method was used to evaluate the influence of acute and long-term nifedipine treatment on renal tubular sodium reabsorption. 2. In the acute study, after a 4 week placebo period two doses of 20 mg of nifedipine decreased supine blood pressure from 155...... were also unchanged, as were potassium clearance, urine flow and body weight. 3. In the long-term study, lithium clearance, glomerular filtration rate, sodium clearance, potassium clearance, urine flow and body fluid volumes were measured after a 4 weeks placebo period and after 6 and 12 weeks....../101 (20.6/13.5) +/- 11/4 (1.5/0.5) to 139/88 (18.5/11.7) +/- 16/9 (2.1/1.2) mmHg (kPa) (means +/- SD; P less than 0.01). Lithium clearance, glomerular filtration rate and sodium clearance did not change. Therefore the calculated values of absolute proximal and absolute distal sodium reabsorption rates...

Effect of tip clearance on performance of small axial hydraulic turbine

Science.gov (United States)

Boynton, J. L.; Rohlik, H. E.

1976-01-01

The first two stages of a six stage liquid oxygen turbine were tested in water. One and two stage performance was determined for one shrouded and two unshrouded blade end configurations over ranges of clearance and blade-jet speed ratio. First stage, two stage, and second stage efficiencies are included as well as the effect of clearance on mass flow for two stage operation.

Thickness and clearance visualization based on distance field of 3D objects

Directory of Open Access Journals (Sweden)

Masatomo Inui

2015-07-01

Full Text Available This paper proposes a novel method for visualizing the thickness and clearance of 3D objects in a polyhedral representation. The proposed method uses the distance field of the objects in the visualization. A parallel algorithm is developed for constructing the distance field of polyhedral objects using the GPU. The distance between a voxel and the surface polygons of the model is computed many times in the distance field construction. Similar sets of polygons are usually selected as close polygons for close voxels. By using this spatial coherence, a parallel algorithm is designed to compute the distances between a cluster of close voxels and the polygons selected by the culling operation so that the fast shared memory mechanism of the GPU can be fully utilized. The thickness/clearance of the objects is visualized by distributing points on the visible surfaces of the objects and painting them with a unique color corresponding to the thickness/clearance values at those points. A modified ray casting method is developed for computing the thickness/clearance using the distance field of the objects. A system based on these algorithms can compute the distance field of complex objects within a few minutes for most cases. After the distance field construction, thickness/clearance visualization at a near interactive rate is achieved.

Growing Homophilic Networks Are Natural Navigable Small Worlds.

Science.gov (United States)

Malkov, Yury A; Ponomarenko, Alexander

2016-01-01

Navigability, an ability to find a logarithmically short path between elements using only local information, is one of the most fascinating properties of real-life networks. However, the exact mechanism responsible for the formation of navigation properties remained unknown. We show that navigability can be achieved by using only two ingredients present in the majority of networks: network growth and local homophily, giving a persuasive answer how the navigation appears in real-life networks. A very simple algorithm produces hierarchical self-similar optimally wired navigable small world networks with exponential degree distribution by using only local information. Adding preferential attachment produces a scale-free network which has shorter greedy paths, but worse (power law) scaling of the information extraction locality (algorithmic complexity of a search). Introducing saturation of the preferential attachment leads to truncated scale-free degree distribution that offers a good tradeoff between these parameters and can be useful for practical applications. Several features of the model are observed in real-life networks, in particular in the brain neural networks, supporting the earlier suggestions that they are navigable.

Growing Homophilic Networks Are Natural Navigable Small Worlds.

Directory of Open Access Journals (Sweden)

Yury A Malkov

Full Text Available Navigability, an ability to find a logarithmically short path between elements using only local information, is one of the most fascinating properties of real-life networks. However, the exact mechanism responsible for the formation of navigation properties remained unknown. We show that navigability can be achieved by using only two ingredients present in the majority of networks: network growth and local homophily, giving a persuasive answer how the navigation appears in real-life networks. A very simple algorithm produces hierarchical self-similar optimally wired navigable small world networks with exponential degree distribution by using only local information. Adding preferential attachment produces a scale-free network which has shorter greedy paths, but worse (power law scaling of the information extraction locality (algorithmic complexity of a search. Introducing saturation of the preferential attachment leads to truncated scale-free degree distribution that offers a good tradeoff between these parameters and can be useful for practical applications. Several features of the model are observed in real-life networks, in particular in the brain neural networks, supporting the earlier suggestions that they are navigable.

SU-F-P-42: “To Navigate, Or Not to Navigate: HDR BT in Recurrent Spine Lesions”

Energy Technology Data Exchange (ETDEWEB)

Voros, L; Cohen, G; Zaider, M; Yamada, Y [Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2016-06-15

Purpose: We compare the accuracy of HDR catheter placement for paraspinal lesions using O-arm CBCT imaging combined with StealthStation navigation and traditional fluoroscopically guided catheter placement. Methods: CT and MRI scans were acquired pre-treatment to outline the lesions and design treatment plans (pre-plans) to meet dosimetric constrains. The pre-planned catheter trajectories were transferred into the StealthStation Navigation system prior to the surgery. The StealthStation is an infra red (IR) optical navigation system used for guidance of surgical instruments. An intraoperative CBCT scan (O-arm) was acquired with reference IR optical fiducials anchored onto the patient and registered with the preplan image study to guide surgical instruments in relation to the patients’ anatomy and to place the brachytherapy catheters along the pre-planned trajectories. The final treatment plan was generated based on a 2nd intraoperative CBCT scan reflecting achieved implant geometry. The 2nd CBCT was later registered with the initial CT scan to compare the preplanned dwell positions with actual dwell positions (catheter placements). Similar workflow was used in placement of 8 catheters (1 patient) without navigation, but under fluoroscopy guidance in an interventional radiology suite. Results: A total of 18 catheters (3 patients) were placed using navigation assisted surgery. Average displacement of 0.66 cm (STD=0.37cm) was observed between the pre-plan source positions and actual source positions in the 3 dimensional space. This translates into an average 0.38 cm positioning error in one direction including registration errors, digitization errors, and the surgeons ability to follow the planned trajectory. In comparison, average displacement of non-navigated catheters was 0.50 cm (STD=0.22cm). Conclusion: Spinal lesion HDR brachytherapy planning is a difficult task. Catheter placement has a direct impact on target coverage and dose to critical structures. While

Energy Performance and Radial Force of a Mixed-Flow Pump with Symmetrical and Unsymmetrical Tip Clearances

Directory of Open Access Journals (Sweden)

Yue Hao

2017-01-01

Full Text Available The energy performance and radial force of a mixed flow pump with symmetrical and unsymmetrical tip clearance are investigated in this paper. As the tip clearance increases, the pump head and efficiency both decrease. The center of the radial force on the principal axis is located at the coordinate origin when the tip clearance is symmetrical, and moves to the third quadrant when the tip clearance is unsymmetrical. Analysis results show that the total radial force on the principal axis is closely related to the fluctuation of mass flow rate in each single flow channel. Unsteady simulations show that the dominant frequencies of radial force on the hub and blade correspond to the blade number, vane number, or double blade number because of the rotor stator interaction. The radial force on the blade pressure side decreases with the tip clearance increase because of leakage flow. The unsymmetrical tip clearances in an impeller induce uneven leakage flow rate and then result in unsymmetrical work ability of each blade and flow pattern in each channel. Thus, the energy performance decreases and the total radial force increases for a mixed flow pump with unsymmetrical tip clearance.

76 FR 24920 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2011-05-03

... precision requirements or power calculations that justify the proposed sample size, the expected response... Collection; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on Agency Service... Information Collection Request (Generic ICR): ``Generic Clearance for the Collection of Qualitative Feedback...

76 FR 35069 - Agency Information Collection Activities; Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2011-06-15

... precision requirements or power calculations that justify the proposed sample size, the expected response...; Proposed Collection; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on... (Generic ICR): ``Generic Clearance for the Collection of Qualitative Feedback on Agency Service Delivery...

78 FR 74175 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2013-12-10

... precision requirements or power calculations that justify the proposed sample size, the expected response...: Proposed Collection; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on... Information Collection Request (Generic ICR): ``Generic Clearance for the Collection of Qualitative Feedback...

77 FR 52708 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2012-08-30

... calculations that justify the proposed sample size, the expected response rate, methods for assessing potential...: Proposed Collection; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on... Information Collection request (Generic ICR): ``Generic Clearance for the Collection of Qualitative Feedback...

76 FR 9819 - Agency Information Collection Activities: Proposed Collection; Generic Clearance for the...

Science.gov (United States)

2011-02-22

...; Generic Clearance for the Collection of Qualitative Feedback on Agency Service Delivery; Correction AGENCY...: Proposed Collection; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on... Regulatory Commission, Office of Personnel Management, Small Business Administration, and U.S. Agency for...

Turbine Engine Clearance Control Systems: Current Practices and Future Directions

Science.gov (United States)

Lattime, Scott B.; Steinetz, Bruce M.

2002-01-01

Improved blade tip sealing in the high pressure compressor (HPC) and high pressure turbine (HPT) can provide dramatic reductions in specific fuel consumption (SFC), time-on-wing, compressor stall margin, and engine efficiency as well as increased payload and mission range capabilities. Maintenance costs to overhaul large commercial gas turbine engines can easily exceed $1M. Engine removal from service is primarily due to spent exhaust gas temperature (EGT) margin caused mainly by the deterioration of HPT components. Increased blade tip clearance is a major factor in hot section component degradation. As engine designs continue to push the performance envelope with fewer parts and the market drives manufacturers to increase service life, the need for advanced sealing continues to grow. A review of aero gas turbine engine HPT performance degradation and the mechanisms that promote these losses are discussed. Benefits to the HPT due to improved clearance management are identified. Past and present sealing technologies are presented along with specifications for next generation engine clearance control systems.

Regulation Concepts for Clearance Level of Radionuclide in Solid Materials

International Nuclear Information System (INIS)

Nanang Triagung Edi Hermawan

2008-01-01

Practices of nuclear energy have expanded in some fields such as researches and development, educations, agricultures, medicines and industries. Every practice beside give much benefit, could generate residue or waste. Radioactive waste needs management to ensure the safety of workers, member of the public, and for the eternal of environment. The product of radioactive waste management, in generally, is some containment of radionuclide concentration in solid matrix material after immobilization or conditioning process. Some kind of processed radioactive wastes with short half live then decay faster to stabile condition. The decay will reach clearance level in sometimes, so from the radiation protection views is harmless. This materials above didn’t need control and must be cleared from all determinate and regulation aspects of radioactive material practices. There is clearance for harmless material off course will be simplify management task and efficiency of money. So the regulation about clearance levels will be important as law basic for technical practices in field. (author)

Dynamic Studies of Lung Fluid Clearance with Phase Contrast Imaging

International Nuclear Information System (INIS)

Kitchen, Marcus J.; Williams, Ivan; Irvine, Sarah C.; Morgan, Michael J.; Paganin, David M.; Lewis, Rob A.; Pavlov, Konstantin; Hooper, Stuart B.; Wallace, Megan J.; Siu, Karen K. W.; Yagi, Naoto; Uesugi, Kentaro

2007-01-01

Clearance of liquid from the airways at birth is a poorly understood process, partly due to the difficulties of observing and measuring the distribution of air within the lung. Imaging dynamic processes within the lung in vivo with high contrast and spatial resolution is therefore a major challenge. However, phase contrast X-ray imaging is able to exploit inhaled air as a contrast agent, rendering the lungs of small animals visible due to the large changes in the refractive index at air/tissue interfaces. In concert with the high spatial resolution afforded by X-ray imaging systems (<100 μm), propagation-based phase contrast imaging is ideal for studying lung development. To this end we have utilized intense, monochromatic synchrotron radiation, together with a fast readout CCD camera, to study fluid clearance from the lungs of rabbit pups at birth. Local rates of fluid clearance have been measured from the dynamic sequences using a single image phase retrieval algorithm

Understanding of the Interaction between Clearance Leakage Flow and Main Passage Flow in a VGT Turbine

Directory of Open Access Journals (Sweden)

Ben Zhao

2015-02-01

Full Text Available The clearance flow between the nozzle and endwall in a variable geometry turbine (VGT has been numerically investigated to understand the clearance effect on the VGT performance and internal flow. It was found that the flow rate through turbine increases but the turbine efficiency decreases with height of clearance. Detailed flow field analyses indicated that most of the efficiency loss resulting from the leakage flow occurs at the upstream of the rotor area, that is, in the nozzle endwall clearance and between the nozzle vanes. There are two main mechanisms associated with this efficiency loss. One is due to the formation of the local vortex flow structure between the clearance flow and the main flow. The other is due to the impact of the clearance flow on the main flow after the nozzle throat. This impact reduces the span of shockwave with increased shockwave magnitude by changing the trajectory of the main flow.

The effects of selected air pollutants on clearance of titanic oxide particles from the lungs of rats.

Science.gov (United States)

Ferin, J; Leach, L J

1975-09-01

A procedure utilizing the lung clearance kinetics of titanic oxide (TiO2) particles was used to determine the effects of inhaled sulphur dioxide (SO2) and nitrogen oxides (NO x) on particle clearance. The procedure is reproducible and mainly tests clearance mechanisms involving alveolar macrophages and the mucociliary transport system at the alveolobronchial clearance pathway. At low SO2 or NOx exposures enhanced particle clearance was observed. Lung clearance was depressed at 15 and 24 ppm of NO2 after 22 exposures as well as at 20 ppm of SO2 after 11 exposures, and also at 1 ppm of SO2 after 25 exposures. Dose-response curves for the SO2 and NOx exposures showed differences explainable by the routes by which these gases reach the alveolar macrophages.

Automated Real-Time Clearance Analyzer (ARCA), Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The Automated Real-Time Clearance Analyzer (ARCA) addresses the future safety need for Real-Time System-Wide Safety Assurance (RSSA) in aviation and progressively...

Ego-motion based on EM for bionic navigation

Science.gov (United States)

Yue, Xiaofeng; Wang, L. J.; Liu, J. G.

2015-12-01

Researches have proved that flying insects such as bees can achieve efficient and robust flight control, and biologists have explored some biomimetic principles regarding how they control flight. Based on those basic studies and principles acquired from the flying insects, this paper proposes a different solution of recovering ego-motion for low level navigation. Firstly, a new type of entropy flow is provided to calculate the motion parameters. Secondly, EKF, which has been used for navigation for some years to correct accumulated error, and estimation-Maximization, which is always used to estimate parameters, are put together to determine the ego-motion estimation of aerial vehicles. Numerical simulation on MATLAB has proved that this navigation system provides more accurate position and smaller mean absolute error than pure optical flow navigation. This paper has done pioneering work in bionic mechanism to space navigation.

Cancer Patient Navigator Tasks across the Cancer Care Continuum

Science.gov (United States)

Braun, Kathryn L.; Kagawa-Singer, Marjorie; Holden, Alan E. C.; Burhansstipanov, Linda; Tran, Jacqueline H.; Seals, Brenda F.; Corbie-Smith, Giselle; Tsark, JoAnn U.; Harjo, Lisa; Foo, Mary Anne; Ramirez, Amelie G.

2011-01-01

Cancer patient navigation (PN) programs have been shown to increase access to and utilization of cancer care for poor and underserved individuals. Despite mounting evidence of its value, cancer patient navigation is not universally understood or provided. We describe five PN programs and the range of tasks their navigators provide across the cancer care continuum (education and outreach, screening, diagnosis and staging, treatment, survivorship, and end-of-life). Tasks are organized by their potential to make cancer services understandable, available, accessible, affordable, appropriate, and accountable. Although navigators perform similar tasks across the five programs, their specific approaches reflect differences in community culture, context, program setting, and funding. Task lists can inform the development of programs, job descriptions, training, and evaluation. They also may be useful in the move to certify navigators and establish mechanisms for reimbursement for navigation services. PMID:22423178

75 FR 38775 - Proposed Information Collection; Comment Request; Generic Clearance for Customer Satisfaction...

Science.gov (United States)

2010-07-06

...; Generic Clearance for Customer Satisfaction Research AGENCY: U.S. Census Bureau. ACTION: Notice. SUMMARY... Bureau is requesting an extension of the generic clearance to conduct customer satisfaction research... on feedback from its various customer satisfaction research efforts. Each research design is reviewed...

75 FR 80542 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2010-12-22

... calculations that justify the proposed sample size, the expected response rate, methods for assessing potential...; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on Agency Service Delivery... Collection Request (Generic ICR): ``Generic Clearance for the Collection of Qualitative Feedback on Agency...

76 FR 12140 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2011-03-04

... calculations that justify the proposed sample size, the expected response rate, methods for assessing potential...; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on Agency Service Delivery... Information Collection Request (Generic ICR): ``Generic Clearance for the Collection of Qualitative Feedback...

76 FR 19826 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2011-04-08

... calculations that justify the proposed sample size, the expected response rate, methods for assessing potential... Request; Generic Clearance for the Collection of Qualitative Feedback on Agency Service Delivery AGENCY... (Generic ICR): ``Generic Clearance for the Collection of Qualitative Feedback on Agency Service Delivery...

76 FR 17861 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2011-03-31

... requirements or power calculations that justify the proposed sample size, the expected response rate, methods...; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on Agency Service Delivery... Information Collection Request (Generic ICR): ``Generic Clearance for the Collection of Qualitative Feedback...

76 FR 41280 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2011-07-13

... proposed sample size, the expected response rate, methods for assessing potential non-response bias, the... Activities: Proposed Collection; Comment Request; Generic Clearance for the Collection of Qualitative...): ``Generic Clearance for the Collection of Qualitative Feedback on Agency Service Delivery '' to OMB for...

76 FR 25693 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2011-05-05

... requirements or power calculations that justify the proposed sample size, the expected response rate, methods... Collection; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on Agency Service... Collection Request (Generic ICR): ``Generic Clearance for the Collection of Qualitative Feedback on Agency...

Rosetta Star Tracker and Navigation Camera

DEFF Research Database (Denmark)

Thuesen, Gøsta

1998-01-01

Proposal in response to the Invitation to Tender (ITT) issued by Matra Marconi Space (MSS) for the procurement of the ROSETTA Star Tracker and Navigation Camera.......Proposal in response to the Invitation to Tender (ITT) issued by Matra Marconi Space (MSS) for the procurement of the ROSETTA Star Tracker and Navigation Camera....

[Medical clearance for missions abroad (EEU): definitions, recommendations for use and performance].

Science.gov (United States)

Kollaritsch, Herwig; Wenisch, Christoph; Hatz, Christoph; von Laer, Gunther; Bauer, Bernd; Hollenstein, Ursula; Haditsch, Martin; Diridl, Gerhard; Malinowski, Waldemar; Jeschko, Eva; Payer-Neundlinger, Gabriela; Speiser-Remp, Nicole; Pichler, Hannes E T; Rumpold, Helmut; Stemberger, Heinrich; Eder, Gerald; Wiedermann, Gerhard; Wiedermann, Ursula

2007-01-01

Standards for medical clearance for private or business missions abroad are--at least in the German speaking countries--not clearly defined and mostly derived from the old terminus "Tropentauglichkeit" which means fit for mission in the tropics. The authors now define a new standard, called "Entsendungstauglichkeitsuntersuchung" which means clearance of fitness for all types of missions abroad, independent of distinct climatic zones. To meet the inhomogenous requirements of different institutions and different types of missions the medical examination proposed follows a modular structure to optimize economic and medical use of resources. Moreover, as Austria, Germany and Switzerland have different legal and economic postulates, the medical examination has to be adapted to the different premises. The definition and description of this special type of "medical clearance for missions abroad" is supplemented by recommendations for definitions of clients who should undergo such an investigation and the professionals who should perform this type of investigation. Additionally, results of this type of medical clearance are defined and prophylactic aspects in terms of pre-travel advice are mentioned.

Adalimumab Dose Tapering in Psoriasis: Predictive Factors for Maintenance of Complete Clearance.

Science.gov (United States)

Hansel, Katharina; Bianchi, Leonardo; Lanza, Francesco; Bini, Vittorio; Stingeni, Luca

2017-03-10

Psoriasis can be managed successfully with long-term biologics. Real-life clinical practice may require dose tapering as a therapeutic option to reduce the risk of drug-exposure and to increase cost-effectiveness. The responsiveness to extended intervals between adalimumab doses and the possible predictive factors of maintenance of complete clearance were studied in a retrospective 7-year single-centre analysis. Thirty patients who achieved complete clearance with adalimumab underwent dose tapering, progressively extending between-dose intervals (to 21-28 days). Sixty percent of subjects (group A) maintained complete clearance, whereas 40.0% (group B) relapsed and were switched back to the standard dosage to re-achieve complete clearance. Body mass index (BMI) and time to achieve Psoriasis Area Severity Index (PASI-100) with adalimumab standard treatment before dose tapering were significantly lower in group A than in group B (multi-variate Cox regression: p < 0.05, Kaplan-Meier analysis: p < 0.001, respectively). This study suggests that patients with lower BMI and shorter time to achieve PASI-100 with adalimumab standard dose were significantly more likely to be candidates for dose tapering.

Lithium clearance method and the renal response to low-dose dopamine in man

DEFF Research Database (Denmark)

Olsen, N V; Olsen, M H; Fogh-Andersen, N

1993-01-01

.00 hours on three different occasions. After an overnight fast, the subjects were water-loaded and clearance studies were started at 09.00 hours with a 1h baseline period and three 1h periods during dopamine infusion. 2. Baseline sodium clearance with placebo was 0.65 +/- 0.35 ml/min, but with lithium......-induced changes in effective renal plasma flow, glomerular filtration rate or osmolal clearance. Neither lithium nor dopamine influenced plasma concentrations of renin, aldosterone or atrial natriuretic peptide. 4. In conclusion, single test doses of lithium, as normally used in lithium clearance studies......1. The effect of a single dose of lithium on renal function before and during intravenous infusion of dopamine (3 micrograms min-1 kg-1) was investigated in 12 healthy males. In a double-blind and randomized design, 450mg or 600mg of lithium carbonate or placebo was administered orally at 22...

Lithium clearance method and the renal response to low-dose dopamine in man

DEFF Research Database (Denmark)

Olsen, Niels Vidiendal; Olsen, M H; Fogh-Andersen, N

1993-01-01

.00 hours on three different occasions. After an overnight fast, the subjects were water-loaded and clearance studies were started at 09.00 hours with a 1h baseline period and three 1h periods during dopamine infusion. 2. Baseline sodium clearance with placebo was 0.65 +/- 0.35 ml/min, but with lithium...... in effective renal plasma flow, glomerular filtration rate or osmolal clearance. Neither lithium nor dopamine influenced plasma concentrations of renin, aldosterone or atrial natriuretic peptide. 4. In conclusion, single test doses of lithium, as normally used in lithium clearance studies, increase baseline......1. The effect of a single dose of lithium on renal function before and during intravenous infusion of dopamine (3 micrograms min-1 kg-1) was investigated in 12 healthy males. In a double-blind and randomized design, 450mg or 600mg of lithium carbonate or placebo was administered orally at 22...

Turbine blade tip clearance measurement using a skewed dual-beam fiber optic sensor

Science.gov (United States)

Ye, De-chao; Duan, Fa-jie; Guo, Hao-tian; Li, Yangzong; Wang, Kai

2012-08-01

Optimization and active control of the tip clearance of turbine blades has been identified as a key to improve fuel efficiency, reduce emission, and increase service life of the engine. However, reliable and real-time tip clearance measurement is difficult due to the adverse environmental conditions that are typically found in a turbine. We describe a dual-beam fiber optic measurement system that can measure the tip timing and tip clearance simultaneously. Because the tip timing information is used to calculate the tip clearance, the method is insensitive to the signal intensity variation caused by fluctuations in environmental conditions such as light source instability, contamination, and blade tip imperfection. The system was calibrated and tested using experimental rotors. The test results indicated a high resolution of 4.5 μm and measurement accuracy of ±20 μm over the rotation speed range of 2000 to 10,000 rpm.

Visual navigation using edge curve matching for pinpoint planetary landing

Science.gov (United States)

Cui, Pingyuan; Gao, Xizhen; Zhu, Shengying; Shao, Wei

2018-05-01

Pinpoint landing is challenging for future Mars and asteroid exploration missions. Vision-based navigation scheme based on feature detection and matching is practical and can achieve the required precision. However, existing algorithms are computationally prohibitive and utilize poor-performance measurements, which pose great challenges for the application of visual navigation. This paper proposes an innovative visual navigation scheme using crater edge curves during descent and landing phase. In the algorithm, the edge curves of the craters tracked from two sequential images are utilized to determine the relative attitude and position of the lander through a normalized method. Then, considering error accumulation of relative navigation, a method is developed. That is to integrate the crater-based relative navigation method with crater-based absolute navigation method that identifies craters using a georeferenced database for continuous estimation of absolute states. In addition, expressions of the relative state estimate bias are derived. Novel necessary and sufficient observability criteria based on error analysis are provided to improve the navigation performance, which hold true for similar navigation systems. Simulation results demonstrate the effectiveness and high accuracy of the proposed navigation method.

Fuzzy Behavior Modulation with Threshold Activation for Autonomous Vehicle Navigation

Science.gov (United States)

Tunstel, Edward

2000-01-01

This paper describes fuzzy logic techniques used in a hierarchical behavior-based architecture for robot navigation. An architectural feature for threshold activation of fuzzy-behaviors is emphasized, which is potentially useful for tuning navigation performance in real world applications. The target application is autonomous local navigation of a small planetary rover. Threshold activation of low-level navigation behaviors is the primary focus. A preliminary assessment of its impact on local navigation performance is provided based on computer simulations.

Radioactive clearance discharge of effluent from nuclear and radiation facilities

International Nuclear Information System (INIS)

Liu Xinhua; Xu Chunyan

2013-01-01

On the basis of the basic concepts of radiation safety management system exemption, exclusion and clearance, we expound that the general industrial gaseous and liquid effluent discharges are exempted or excluded, gaseous and liquid effluent discharged from nuclear and radiation facilities are clearance, and non-radioactive. The main purpose of this paper is to clarify the concepts, reach a consensus that the gaseous and liquid effluent discharged from nuclear and radiation facilities are non-radioactive and have no hazard to human health and natural environment. (authors)

76 FR 27337 - Houston/Galveston Navigation Safety Advisory Committee

Science.gov (United States)

2011-05-11

... DEPARTMENT OF HOMELAND SECURITY Coast Guard [USCG-2010-1116] Houston/Galveston Navigation Safety...: The Houston/Galveston Navigation Safety Advisory Committee postponed its originally scheduled February... Houston Ship Channel, and various other navigation safety matters in the Galveston Bay area. The meeting...

Visual Guided Navigation

National Research Council Canada - National Science Library

Banks, Martin

1999-01-01

.... Similarly, the problem of visual navigation is the recovery of an observer's self-motion with respect to the environment from the moving pattern of light reaching the eyes and the complex of extra...

Effects and outcome of Tamsulosin more than just stone clearance after extracorporeal shock wave lithotripsy for renal calculi

International Nuclear Information System (INIS)

Qadri, S. S. U.; Khalid, S. E.; Mahmud, S. M.

2014-01-01

Objective: To determine the effect of Tamsulosin, as adjunctive medical therapy after Extracorporeal Shock Wave Lithotripsy for renal stones on rate of stone clearance, clearance time, pain intensity during stone clearance, steinstrasse formation and auxiliary surgical intervention required. Method: A prospective randomized controlled study was carried out in 120 patients who underwent ESWL for renal stones of 0.5-2.0 cm. They were randomized into study and control group in which Tamsulosin 0.4mg/day was given in former as an adjunctive medical therapy. All patients underwent ESWL every 2 weeks until complete stone clearance for 8 weeks. The parameters assessed were stone clearance, clearance time, pain intensity and effect on steinstrasse. Results: Of the 120 patients 60 were in each group. The stone clearance rate was greater in study than in control group, 58(96.7%) vs. 48(80%) respectively, (p<0.004). The mean stone clearance time was observed earlier in study group as compared to control group with significant statistical difference in stone size between 0.6-1.5 cm. The mean intensity of pain patients experienced according to Visual analogue scale (VAS) was significantly less in study group (p<0.002). The rate of steinstrasse formation was observed to be higher in control than in study group 15(25%) vs 6(10%) respectively(p<0.003), while its spontaneous clearance was higher in study group than in control group 83.3% vs 33.3% (p<0.03). Conclusion: Tamsulosin significantly increases stone clearance after shock wave lithotripsy for renal stones. It also appeared to facilitate earlier stone clearance, reduces severity of pain, reduces the incidence of steinstrasse formation and tends to facilitate its spontaneous clearance. (author)

Development of a Novel System to Measure a Clearance of a Passenger Platform

Science.gov (United States)

Shimizu, M.; Oizumi, J.; Matsuoka, R.; Takeda, H.; Okukura, H.; Ooya, A.; Koike, A.

2016-06-01

Clearances of a passenger platform at a railway station should be appropriately maintained for safety of both trains and passengers. In most Japanese railways clearances between a platform and a train car is measured precisely once or twice a year. Because current measurement systems operate on a track, the closure of the track is unavoidable. Since the procedure of the closure of a track is time-consuming and bothersome, we decided to develop a new system to measure clearances without the closure of a track. A new system is required to work on a platform and the required measurement accuracy is less than several millimetres. We have adopted a 3D laser scanner and stop-and-go operation for a new system. The current systems on a track measure clearances continuously at walking speed, while our system on a platform measures clearances at approximately ten metres intervals. The scanner controlled by a PC acquires a set of point data at each measuring station. Edge points of the platform, top and side points of two rails are detected from the acquired point data. Finally clearances of the platform are calculated by using the detected feature points of the platform and the rails. The results of an experiment using a prototype of our system show that the measurement accuracy by our system would be satisfactory, but our system would take more time than the current systems. Since our system requires no closure of a track, we conclude that our system would be convenient and effective.

Paediatric patient navigation models of care in Canada: An environmental scan.

Science.gov (United States)

Luke, Alison; Doucet, Shelley; Azar, Rima

2018-05-01

(1) To provide other organizations with useful information when implementing paediatric navigation programs and (2) to inform the implementation of a navigation care centre in New Brunswick for children with complex health conditions. This environmental scan consisted of a literature review of published and grey literature for paediatric patient navigation programs across Canada. Additional programs were found following discussions with program coordinators and navigators. Interviews were conducted with key staff from each program and included questions related to patient condition; target population and location; method delivery; navigator background; and navigator roles. Data analysis included analysis of interviews and identification of common themes across the different programs. We interviewed staff from 19 paediatric navigation programs across Canada. Programs varied across a number of different themes, including: condition and disease type, program location (e.g., hospital or clinic), navigator background (e.g., registered nurse or peer/lay navigator) and method of delivery (e.g., phone or face-to-face). Overall, navigator roles are similar across all programs, including advocacy, education, support and assistance in accessing resources from both within and outside the health care system. This scan offers a road map of Canadian paediatric navigation programs. Knowledge learned from this scan will inform stakeholders who are either involved in the delivery of paediatric patient navigation programs or planning to implement such a program. Specifically, our scan informed the development of a navigation centre for children with complex health conditions in New Brunswick.

Effects of a Nonuniform Tip Clearance Profile on the Performance and Flow Field in a Centrifugal Compressor

Directory of Open Access Journals (Sweden)

Yohan Jung

2012-01-01

Full Text Available This paper presents a numerical investigation of the effects of a nonuniform tip clearance profile on the performance and flow field in a centrifugal compressor with a vaneless diffuser. This study focuses in particular on the magnitude and location of the wake. Six impellers with different tip clearance profiles were tested in the flow simulations. The accuracy of the numerical simulations was assessed by comparing the experimental data with the computational results for a system characterized by the original tip clearance. Although the performance improved for low tip clearances, a low tip clearance at the trailing edge improved the compressor performance more significantly than a low tip clearance at the leading edge. The flow field calculated for a system characterized by a low tip clearance at the trailing edge produced a more uniform velocity distribution both in the circumferential and in the axial directions at the impeller exit because the wake magnitude was reduced. As a consequence, this impeller provided a better potential for diffusion processes inside a vaneless diffuser.

78 FR 69643 - Proposed Information Collection; Comment Request; Generic Clearance for Customer Satisfaction...

Science.gov (United States)

2013-11-20

... Clearance for Customer Satisfaction Research AGENCY: U.S. Census Bureau, Commerce. ACTION: Notice. SUMMARY... requesting an extension of the generic clearance to conduct customer satisfaction research which may be in... feedback from its various customer satisfaction research efforts. Each research design is reviewed for...

76 FR 63301 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2011-10-12

... requirements or power calculations that justify the proposed sample size, the expected response rate, methods... Collection; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on Agency Service... Clearance for the Collection of Qualitative Feedback on Agency Service Delivery'' to OMB for approval under...

76 FR 15027 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2011-03-18

... clustering), the precision requirements or power calculations that justify the proposed sample size, the...; Comment Request; Generic Clearance for the Collection of Qualitative Feedback on Agency Service Delivery... Clearance for the Collection of Qualitative Feedback on Agency Service Delivery'' to OMB for approval under...

Railway clearance intrusion detection method with binocular stereo vision

Science.gov (United States)

Zhou, Xingfang; Guo, Baoqing; Wei, Wei

2018-03-01

In the stage of railway construction and operation, objects intruding railway clearance greatly threaten the safety of railway operation. Real-time intrusion detection is of great importance. For the shortcomings of depth insensitive and shadow interference of single image method, an intrusion detection method with binocular stereo vision is proposed to reconstruct the 3D scene for locating the objects and judging clearance intrusion. The binocular cameras are calibrated with Zhang Zhengyou's method. In order to improve the 3D reconstruction speed, a suspicious region is firstly determined by background difference method of a single camera's image sequences. The image rectification, stereo matching and 3D reconstruction process are only executed when there is a suspicious region. A transformation matrix from Camera Coordinate System(CCS) to Track Coordinate System(TCS) is computed with gauge constant and used to transfer the 3D point clouds into the TCS, then the 3D point clouds are used to calculate the object position and intrusion in TCS. The experiments in railway scene show that the position precision is better than 10mm. It is an effective way for clearance intrusion detection and can satisfy the requirement of railway application.

Losses and blade tip clearance for a centrifugal compressor

Directory of Open Access Journals (Sweden)

Oana DUMITRESCU

2018-06-01

Full Text Available The present paper presents the numerical analysis for a transonic centrifugal compressor using steady state CFD. The blade tip clearance effect over the position of shock waves, tip losses and the performances of the impeller are studied. Numerical simulations have been performed using RANS modelling, with the k-omega SST turbulence model (Shear Stress Transport. Eight cases were taken into consideration for the impeller with the following blade tip clearances values: 0 mm, 0.1 mm, 0.3 mm, 0.4 mm, 0.5mm, 0.7 mm, 1 mm, 2 mm, at the same operating conditions. For the entire stage only seven cases were studied, without the value for 0.1 mm because of its abnormal behaviour, as can be seen in the case of the impeller simulations. Results showed that the position of the shock wave does not change with the increase of the tip clearance. Aerodynamic losses due to shock wave, secondary flow and turbulence can be seen in the polytropic efficiency of the centrifugal impeller and the difference between the two extreme cases is about 3.2 %.

The provision of clearances accuracy in piston - cylinder mating

Science.gov (United States)

Glukhov, V. I.; Shalay, V. V.

2017-08-01

The paper is aimed at increasing the quality of the pumping equipment in oil and gas industry. The main purpose of the study is to stabilize maximum values of productivity and durability of the pumping equipment based on the selective assembly of the cylinder-piston kinematic mating by optimization criterion. It is shown that the minimum clearance in the piston-cylinder mating is formed by maximum material dimensions. It is proved that maximum material dimensions are characterized by their own laws of distribution within the tolerance limits for the diameters of the cylinder internal mirror and the outer cylindrical surface of the piston. At that, their dispersion zones should be divided into size groups with a group tolerance equal to half the tolerance for the minimum clearance. The techniques for measuring the material dimensions - the smallest cylinder diameter and the largest piston diameter according to the envelope condition - are developed for sorting them into size groups. Reliable control of the dimensions precision ensures optimal minimum clearances of the piston-cylinder mating in all the size groups of the pumping equipment, necessary for increasing the equipment productivity and durability during the production, operation and repair processes.

Tinnitus Patient Navigator

Science.gov (United States)

... Cure About Us Initiatives News & Events Professional Resources Tinnitus Patient Navigator Want to get started on the ... unique and may require a different treatment workflow. Tinnitus Health-Care Providers If you, or someone you ...

Brain-wide pathway for waste clearance captured by contrast-enhanced MRI.

Science.gov (United States)

Iliff, Jeffrey J; Lee, Hedok; Yu, Mei; Feng, Tian; Logan, Jean; Nedergaard, Maiken; Benveniste, Helene

2013-03-01

The glymphatic system is a recently defined brain-wide paravascular pathway for cerebrospinal fluid (CSF) and interstitial fluid (ISF) exchange that facilitates efficient clearance of solutes and waste from the brain. CSF enters the brain along para-arterial channels to exchange with ISF, which is in turn cleared from the brain along para-venous pathways. Because soluble amyloid β clearance depends on glymphatic pathway function, we proposed that failure of this clearance system contributes to amyloid plaque deposition and Alzheimer's disease progression. Here we provide proof of concept that glymphatic pathway function can be measured using a clinically relevant imaging technique. Dynamic contrast-enhanced MRI was used to visualize CSF-ISF exchange across the rat brain following intrathecal paramagnetic contrast agent administration. Key features of glymphatic pathway function were confirmed, including visualization of para-arterial CSF influx and molecular size-dependent CSF-ISF exchange. Whole-brain imaging allowed the identification of two key influx nodes at the pituitary and pineal gland recesses, while dynamic MRI permitted the definition of simple kinetic parameters to characterize glymphatic CSF-ISF exchange and solute clearance from the brain. We propose that this MRI approach may provide the basis for a wholly new strategy to evaluate Alzheimer's disease susceptibility and progression in the live human brain.

Residual kidney function after donor nephrectomy. Assessment by 99mTc-MAG3-Clearance

International Nuclear Information System (INIS)

Hamscho, N.; Doebert, N.; Menzel, C.; Berner, U.; Zaplatnikov, K.; Gruenwald, F.; Wilhelm, A.; Gossmann, J.; Scheuermann, E.H.

2005-01-01

Aim: We evaluated the long-term residual renal function after donor nephrectomy using 99m Tc-mercaptoacetyltriglycin (MAG3)-clearance. Donors, methods: Altogether 49 kidney donors were examined using 99m Tc-MAG3-clearance after nephrectomy for donation to a relative (m:f=11.38; age 55±27 years). The donors were examined 16±8 years postoperatively (1.5-26 years). 42 donors (86%) showed normal creatinine values, whereas the other seven (14%) exhibited slightly elevated levels. 20 donors were examined pre- and postoperatively and compared intraindividually. The kidney function was compared to the age adapted normal values of healthy persons with two kidneys (67-133% of age related mean). Results: After nephrectomy all donors showed a normal perfusion, good secretion, merely physiological intrarenal transit and a normal elimination from the kidneys. The 99m Tc-MAG3-clearance was 69±15% of the normal mean value of healthy carriers of two kidneys regardless of the gender. 20 donors with a preoperative examination showed a significantly reduced total renal function from 84±15% of the mean normal value preoperatively to 60±15% postoperatively (p 99m Tc-MAG3-clearance measured prior to nephrectomy and the clearance levels after nephrectomy. Also, no correlation between the preoperative 99m Tc-MAG3-clearance and the postoperative serum creatinine values could be observed. Althogether, 22% of the donors (11/49) developed arterial hypertension 10±8 years after donation (1-23 years). This corresponds to the normal age prevalence of hypertension in the carriers of two kidneys. Three donors suffered from arterial hypertension prior to the operation. Conclusion: Kidney donors with normal or slightly elevated creatinine values postoperatively show a 99m Tc-MAG3 clearance value of 69% of the mean value of healthy carriers of two kidneys. This may serve as a reference value for healthy carriers of one kidney. In our study we demonstrated a good compensation of the contralateral

Design Issues for MEMS-Based Pedestrian Inertial Navigation Systems

Directory of Open Access Journals (Sweden)

P. S. Marinushkin

2015-01-01

Full Text Available The paper describes design issues for MEMS-based pedestrian inertial navigation systems. By now the algorithms to estimate navigation parameters for strap-down inertial navigation systems on the basis of plural observations have been already well developed. At the same time mathematical and software processing of information in the case of pedestrian inertial navigation systems has its specificity, due to the peculiarities of their functioning and exploitation. Therefore, there is an urgent task to enhance existing fusion algorithms for use in pedestrian navigation systems. For this purpose the article analyzes the characteristics of the hardware composition and configuration of existing systems of this class. The paper shows advantages of various technical solutions. Relying on their main features it justifies a choice of the navigation system architecture and hardware composition enabling improvement of the estimation accuracy of user position as compared to the systems using only inertial sensors. The next point concerns the development of algorithms for complex processing of heterogeneous information. To increase an accuracy of the free running pedestrian inertial navigation system we propose an adaptive algorithm for joint processing of heterogeneous information based on the fusion of inertial info rmation with magnetometer measurements using EKF approach. Modeling of the algorithm was carried out using a specially developed functional prototype of pedestrian inertial navigation system, implemented as a hardware/software complex in Matlab environment. The functional prototype tests of the developed system demonstrated an improvement of the navigation parameters estimation compared to the systems based on inertial sensors only. It enables to draw a conclusion that the synthesized algorithm provides satisfactory accuracy for calculating the trajectory of motion even when using low-grade inertial MEMS sensors. The developed algorithm can be

Ground-Based Global Navigation Satellite System GLONASS (GLObal NAvigation Satellite System) Combined Broadcast Ephemeris Data (daily files) from NASA CDDIS

Data.gov (United States)

National Aeronautics and Space Administration — This dataset consists of ground-based Global Navigation Satellite System (GNSS) GLONASS Combined Broadcast Ephemeris Data (daily files of all distinct navigation...

33 CFR 207.580 - Buffalo Harbor, N.Y.; use, administration, and navigation.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Buffalo Harbor, N.Y.; use, administration, and navigation. 207.580 Section 207.580 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.580 Buffalo Harbor, N.Y.; use...

Navigation system for interstitial brachytherapy

International Nuclear Information System (INIS)

Strassmann, G.; Kolotas, C.; Heyd, R.

2000-01-01

The purpose of the stud was to develop a computed tomography (CT) based electromagnetic navigation system for interstitial brachytherapy. This is especially designed for situations when needles have to be positioned adjacent to or within critical anatomical structures. In such instances interactive 3D visualisation of the needle positions is essential. The material consisted of a Polhemus electromagnetic 3D digitizer, a Pentium 200 MHz laptop and a voice recognition for continuous speech. In addition, we developed an external reference system constructed of Perspex which could be positioned above the tumour region and attached to the patient using a non-invasive fixation method. A specially designed needle holder and patient bed were also developed. Measurements were made on a series of phantoms in order to study the efficacy and accuracy of the navigation system. The mean navigation accuracy of positioning the 20.0 cm length metallic needles within the phantoms was in the range 2.0-4.1 mm with a maximum of 5.4 mm. This is an improvement on the accuracy of a CT-guided technique which was in the range 6.1-11.3 mm with a maximum of 19.4 mm. The mean reconstruction accuracy of the implant geometry was 3.2 mm within a non-ferromagnetic environment. We found that although the needles were metallic this did not have a significant influence. We also found for our experimental setups that the CT table and operation table non-ferromagnetic parts had no significant influence on the navigation accuracy. This navigation system will be a very useful clinical tool for interstitial brachytherapy applications, particularly when critical structures have to be avoided. It also should provide a significant improvement on our existing technique

Benefits of multisensory presentation on perception, memory and navigation

NARCIS (Netherlands)

Philippi, T.G.|info:eu-repo/dai/nl/313711577

2012-01-01

Navigation is the process of planning and following routes to travel from the current location to a target location. In comparison with real world navigation, we have considerable difficulty with navigation in virtual environments. An important cause is that less information is presented in a

Demonstration of a dynamic clearance seal in a rotating test facility.

OpenAIRE

Messenger, Andrew; Williams, Richard; Ingram, Grant; Hogg, Simon; Tibos, Stacie; Seaton, Jon; Charnley, Bernard

2017-01-01

The successful demonstration of the “Aerostatic Seal” in a half scale rotating facility is described in this paper. The Aerostatic seal is a novel dynamic clearance seal specifically designed for steam turbine secondary gas path applications. The seal responds to radial rotor excursions, so a reduced clearance can be maintained compared to conventional labyrinth seal without damage to the seal. This enables increased turbine performance through reduced leakage and increased tolerance of turbi...

Intra-operative colloid administration increases the clearance of a post-operative fluid load

DEFF Research Database (Denmark)

Borup, Tine; Hahn, Robert; Holte, K

2009-01-01

using volume kinetics based on the plasma dilution alone. The pre-operative plasma clearance was compared with the post-operative plasma clearance and patients served as their own control. RESULTS: The urinary excretion averaged 350 ml for the pre-operative infusion and 612 ml post-operatively, which...

76 FR 20967 - Agency Information Collection Activities: Proposed Collection; Comment Request; Generic Clearance...

Science.gov (United States)

2011-04-14

... requirements or power calculations that justify the proposed sample size, the expected response rate, methods... Request; Generic Clearance for the Collection of Qualitative Feedback on Agency Service Delivery AGENCY: U... Clearance for the Collection of Qualitative Feedback on Agency Service Delivery'' to OMB for approval under...

3D-navigation for interstitial stereotactic brachytherapy; 3D-Navigation in der interstitiellen stereotaktischen Brachytherapie

Energy Technology Data Exchange (ETDEWEB)

Auer, T.; Hensler, E.; Eichberger, P.; Bluhm, A.; Lukas, P. [Innsbruck Univ. (Austria). Klinik fuer Strahlentherapie und Radioonkologie; Gunkel, A.; Freysinger, W.; Bale, R.; Thumfart, W.F. [Innsbruck Univ. (Austria). Klinik fuer HNO-Krankheiten; Gaber, O. [Innsbruck Univ. (Austria). Inst. fuer Anatomie

1998-02-01

The aim of this paper is to describe the adaption of 3D-navigation for interstitial brachytherapy. The new method leads to prospective and therefore improved planning of the therapy (position of the needle and dose distribution) and to the possibility of a virtual simulation (control if vessels or nerves are on the pathway of the needle). The EasyGuide Neuro {sup trademark} navigation system (Philips) was adapted in the way, that needles for interstitial bracachytherapy were made connectable to the pointer and correctly displayed on the screen. To determine the positioning accuracy, several attempts were performed to hit defined targets on phantoms. Two methods were used: `Free navigation`, where the needle was under control of the navigation system, and the `guided navigation` where an aligned template was used additionally to lead the needle to the target. In addition a mask system was tested, whether it met the requirements of stable and reproducible positioning. The potential of applying this method is clinical practice was tested with an anatomical specimen. About 91% of all attempts lied within 5 mm. There were even better results on the more rigid table (94%<4 mm). No difference could be seen between both application methods (`free navigation` and `navigation with template`), they showed the same accuracy. (orig./MG) [Deutsch] Es war das Ziel dieser Arbeit, ein 3D-Infrarotnavigationssystem fuer die Anforderungen der interstitiellen stereotaktischen Brachytherapie zu adaptieren. Damit wird die Planung der Therapie verbessert (prospektive Planung der Nadelpositionen und der Dosisverteilung), und eine virtuelle Simulation wird realisierbar (Kontrolle des vorgeplanten Zugangs bezueglich Verletzungsmoeglichkeit von Gefaessen oder Nerven). Das EasyGuide-Neuro {sup trademark} -Navigagationssystem (Philips) wurde so veraendert, dass Nadeln, die in der Brachytherapie Verwendung finden, am Pointer befestigt werden konnten und am Bildschirm angezeigt wurden. Um die

Clearance rate of Mytilus edulis (L.) as a function of current velocity and mussel aggregation

DEFF Research Database (Denmark)

Nielsen, Pernille; Vismann, Bent

2014-01-01

by current velocities up to 1.4 m/sec, whereas experiments with 3 mussels showed that clearance of the mussels decreased progressively at current velocities greater than 0.2 m/sec, and reached 0 L/h per individual at current velocities greater than 0.6 m/sec. The constant feeding at all current velocities......The aim of the current study was to investigate the effect of water current velocities on the clearance rate of Mytilus edulis when different numbers of mussels were used in the experiments. An automatic setup, which controlled and monitored the algal concentration continually, was used to measure...... the effect of increasing current velocity (0.05-1.4 m/sec) on the M. edulis clearance rate. Clearance rate measurements were performed under constant food concentrations of 3,000 cells/mL of Rhodomonas salina on either 3 mussels or 20 mussels. We found that the clearance rate of 20 mussels was unaffected...

Survey of computer vision technology for UVA navigation

Science.gov (United States)

Xie, Bo; Fan, Xiang; Li, Sijian

2017-11-01

Navigation based on computer version technology, which has the characteristics of strong independence, high precision and is not susceptible to electrical interference, has attracted more and more attention in the filed of UAV navigation research. Early navigation project based on computer version technology mainly applied to autonomous ground robot. In recent years, the visual navigation system is widely applied to unmanned machine, deep space detector and underwater robot. That further stimulate the research of integrated navigation algorithm based on computer version technology. In China, with many types of UAV development and two lunar exploration, the three phase of the project started, there has been significant progress in the study of visual navigation. The paper expounds the development of navigation based on computer version technology in the filed of UAV navigation research and draw a conclusion that visual navigation is mainly applied to three aspects as follows.(1) Acquisition of UAV navigation parameters. The parameters, including UAV attitude, position and velocity information could be got according to the relationship between the images from sensors and carrier's attitude, the relationship between instant matching images and the reference images and the relationship between carrier's velocity and characteristics of sequential images.(2) Autonomous obstacle avoidance. There are many ways to achieve obstacle avoidance in UAV navigation. The methods based on computer version technology ,including feature matching, template matching, image frames and so on, are mainly introduced. (3) The target tracking, positioning. Using the obtained images, UAV position is calculated by using optical flow method, MeanShift algorithm, CamShift algorithm, Kalman filtering and particle filter algotithm. The paper expounds three kinds of mainstream visual system. (1) High speed visual system. It uses parallel structure, with which image detection and processing are

Effect of increased surface hydrophobicity via drug conjugation on the clearance of inhaled PEGylated polylysine dendrimers.

Science.gov (United States)

Haque, Shadabul; McLeod, Victoria M; Jones, Seth; Fung, Sandy; Whittaker, Michael; McIntosh, Michelle; Pouton, Colin; Owen, David J; Porter, Christopher J H; Kaminskas, Lisa M

2017-10-01

PEGylated polylysine dendrimers are attractive and well tolerated inhalable drug delivery platforms that have the potential to control the release, absorption kinetics and lung retention time of conjugated drugs. The clinical application of these systems though, would likely require partial substitution of surface PEG groups with drug molecules that are anticipated to alter their lung clearance kinetics and clearance pathways. In the current study, we therefore evaluated the impact of increased surface hydrophobicity via substitution of 50% surface PEG groups with a model hydrophobic drug (α-carboxyl OtButylated methotrexate) on the lung clearance of a Generation 5 PEGylated polylysine dendrimer in rats. PEG substitution with OtBu-methotrexate accelerated lung clearance of the dendrimer by increasing polylysine scaffold catabolism, improving systemic absorption of the intact dendrimer and low molecular weight products of scaffold catabolism, and enhancing mucociliary clearance. These results suggest that the conjugation of hydrophobic drug on the surface of a PEGylated dendrimer is likely to accelerate lung clearance when compared to a fully PEGylated dendrimer. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Navigation in space by X-ray pulsars

CERN Document Server

Emadzadeh, Amir Abbas

2011-01-01

This book covers modeling of X-ray pulsar signals and explains how X-ray pulsar signals can be used to solve the relative navigation problem. It formulates the problem, proposes a recursive solution and analyzes different aspects of the navigation system.

Using radioaerosols to monitor physiotherapy-enhanced mucus clearance at different levels of the bronchial tree

International Nuclear Information System (INIS)

Hasani, A.; Pavia, D.; Clarke, S.W.; Agnew, J.E.

1993-01-01

Patients with airways obstruction often find it difficult to clear excess lung secretions. Frequent coughing can clear the larger airways but may itself further damage the airways ciliated epithelium. Various physiotherapy regimes have been proposed yet objective evidence of their efficacy is sparse. Deposited aerosol particles - with an appropriate label for gamma imaging - can track clearance from different lung regions. Published reports have however tended to be equivocal in respect of clearance from the more distal conducting airways. Questions also arise as to coordination of transport rates at different levels of the bronchial tree. We therefore sought to re-assess requirements for effective analysis of physiotherapy-enhanced clearance to yield data on both peripheral and central airways clearance. (author)

Using radioaerosols to monitor physiotherapy-enhanced mucus clearance at different levels of the bronchial tree

Energy Technology Data Exchange (ETDEWEB)

Hasani, A.; Pavia, D.; Clarke, S.W.; Agnew, J.E. (Royal Free Hospital, London (United Kingdom))

1993-01-01

Patients with airways obstruction often find it difficult to clear excess lung secretions. Frequent coughing can clear the larger airways but may itself further damage the airways ciliated epithelium. Various physiotherapy regimes have been proposed yet objective evidence of their efficacy is sparse. Deposited aerosol particles - with an appropriate label for gamma imaging - can track clearance from different lung regions. Published reports have however tended to be equivocal in respect of clearance from the more distal conducting airways. Questions also arise as to coordination of transport rates at different levels of the bronchial tree. We therefore sought to re-assess requirements for effective analysis of physiotherapy-enhanced clearance to yield data on both peripheral and central airways clearance. (author).

Binding and clearance of Tc-99m pyrophosphate from the lungs of smokers and nonsmokers

International Nuclear Information System (INIS)

Isitman, A.T.; Effros, R.; Collier, B.D.; Palmer, D.W.; Krasnow, A.Z.; Hellman, R.S.; Hacker, A.; Berger, C.; Trembath, L.

1990-01-01

Both acute and chronic lung disorders that affect the alveolar epithelium increase the rate at which aerosolized Tc-99 m DTPA is cleared from the lungs. Transalveolar clearance of Tc-99 DTPA has been used to detect lung injury, but- because smokers have a much faster clearance rate of Tc-99m DTPA-this examination has been limited primarily to nonsmokers. The purpose of this paper is to determine if the clearance of a larger molecule, Tc-99m PYP (molecular weight by ultrafiltration between 1.000 and 3,000 daltons), is also accelerated by smoking. Clearances of each indicator were studies for 6 hours in eight normal nonsmoking subjects and seven (otherwise normal smokers)

Four hour creatinine clearance is better than plasma creatinine for monitoring renal function in critically ill patients

Science.gov (United States)

2012-01-01

Introduction Acute kidney injury (AKI) diagnosis is based on an increase in plasma creatinine, which is a slowly changing surrogate of decreased glomerular filtration rate. We investigated whether serial creatinine clearance, a direct measure of the glomerular filtration rate, provided more timely and accurate information on renal function than serial plasma creatinine in critically ill patients. Methods Serial plasma creatinine and 4-hour creatinine clearance were measured 12-hourly for 24 hours and then daily in 484 patients. AKI was defined either as > 50% increase in plasma creatinine from baseline, or > 33.3% decrease in creatinine clearance. The diagnostic and predictive performance of the two AKI definitions were compared. Results Creatinine clearance decrease diagnosed AKI in 24% of those not diagnosed by plasma creatinine increase on entry. These patients entered the ICU sooner after insult than those diagnosed with AKI by plasma creatinine elevation (P = 0.0041). Mortality and dialysis requirement increased with the change in creatinine clearance-acute kidney injury severity class (P = 0.0021). Amongst patients with plasma creatinine creatinine clearance improved the prediction of AKI considerably (Net Reclassification Improvement 83%, Integrated Discrimination Improvement 0.29). On-entry, creatinine clearance associated with AKI severity and duration (P 33.3% decrease in creatinine clearance over the first 12 hours was associated with a 2.0-fold increased relative risk of dialysis or death. Conclusions Repeated 4-hour creatinine clearance measurements in critically ill patients allow earlier detection of AKI, as well as progression and recovery compared to plasma creatinine. Trial Registration Australian New Zealand Clinical Trials Registry ACTRN012606000032550. PMID:22713519

SLS Navigation Model-Based Design Approach

Science.gov (United States)

Oliver, T. Emerson; Anzalone, Evan; Geohagan, Kevin; Bernard, Bill; Park, Thomas

2018-01-01

The SLS Program chose to implement a Model-based Design and Model-based Requirements approach for managing component design information and system requirements. This approach differs from previous large-scale design efforts at Marshall Space Flight Center where design documentation alone conveyed information required for vehicle design and analysis and where extensive requirements sets were used to scope and constrain the design. The SLS Navigation Team has been responsible for the Program-controlled Design Math Models (DMMs) which describe and represent the performance of the Inertial Navigation System (INS) and the Rate Gyro Assemblies (RGAs) used by Guidance, Navigation, and Controls (GN&C). The SLS Navigation Team is also responsible for the navigation algorithms. The navigation algorithms are delivered for implementation on the flight hardware as a DMM. For the SLS Block 1-B design, the additional GPS Receiver hardware is managed as a DMM at the vehicle design level. This paper provides a discussion of the processes and methods used to engineer, design, and coordinate engineering trades and performance assessments using SLS practices as applied to the GN&C system, with a particular focus on the Navigation components. These include composing system requirements, requirements verification, model development, model verification and validation, and modeling and analysis approaches. The Model-based Design and Requirements approach does not reduce the effort associated with the design process versus previous processes used at Marshall Space Flight Center. Instead, the approach takes advantage of overlap between the requirements development and management process, and the design and analysis process by efficiently combining the control (i.e. the requirement) and the design mechanisms. The design mechanism is the representation of the component behavior and performance in design and analysis tools. The focus in the early design process shifts from the development and

Identification of Clearance and Contact Stiffness in a Simplified Barrel-Cradle Structure of Artillery System

Directory of Open Access Journals (Sweden)

Bing Li

2015-02-01

Full Text Available In gun barrel-cradle structure, the presence of clearance usually changes the dynamic response of muzzle and results in shooting dispersion (under continuous firing condition. The parameter estimation of such clearance nonlinear system is the prerequisite for establishing quantitative relation between the clearance and muzzle disturbance. In this paper, the restoring force surface (RFS method and the nonlinear identification through feedback of outputs (NIFO method are first combined for parameter identification in a simplified barrel-cradle structure. With the RFS method, clearance value can be obtained by analyzing the restoring force plot. Then the contact stiffness can be identified by using NIFO method. This identification process is verified in a single-degree-of-freedom (SDOF system with clearance. To adapt to the rigid-flexible coupled beam system with clearances which is simplified from the barrel-cradle structure, a modification for the combined method mentioned above is proposed. The core idea of the modification is reducing the continuous system to multiple-degree-of-freedom (MDOF system to reserve the nonlinear characteristics through modal transformation matrix. The advantage of this transformation is that the linear parts of the MDOF systems are decoupled, which greatly reduces the difficulty of identification. The simulation results have shown the effectiveness of current method.

Comparative study of conventional PAH and inulin clearance and slope clearance of 131I-o-hippuric acid and 51Cr-EDTA

International Nuclear Information System (INIS)

Berghaeuser, H.

1981-01-01

''Classic'' PAH and inulin clearance were determined in 81 patients with renal anomalies or renal diseases of different genesis and severity. In addition, radioisotope nephrography was carried out after administration of I-131-o-hippuric acid, followed by administration of Cr-51-EDTA. The activity decrease was recorded by a sensor located over the patient's right shoulder; the activities of a serum sample and of the urine excreted after 21 or 31 min were measured, and the findings were compared with those of the classic method. The clearance data calculated on the basis of the soulder measurements were hardly compatible with those of the conventional method in the case of 131 I-o-hippuric acid (r=0.54) and totally incompatible in the case of 51 Cr-EDTA. This means that the method described by Oberhausen is the only accurate method available for a quantitative assessment of the renal function on the basis of measurements of the activity decrease in the body. The activity of urine excreted after 31 min ( 131 I-hippuric acid:r=0.992, 51 Cr-EDTA:r=0.79) is a sufficiently accurate parameter although it is inaccurate at PAH clearance, values > 130 ml/min and inulin clearance values > 30 ml/min. Of the many parameters of radioisotope nephrogram curves, in the case of 131 I-o-hippuric acid only the parameters related to the ascent between 48 and 120 sec or to the secant ascent yield sufficient quantitative information for certain functional regions (r=0.9 resp. r=0.93). In the case of 51 Cr-EDTA, semiquantitative information on the renal function can be obtained by constructing secants on the nephrogram curves (r=0.7 resp. r=0.72). Here as in the case of 131 I-hippuric acid, the contribution of each kidney can be determined individually from the functional analysis of both kidneys. (orig.) [de

The Navigation Metaphor in Security Economics

DEFF Research Database (Denmark)

Pieters, Wolter; Barendse, Jeroen; Ford, Margaret

2016-01-01

The navigation metaphor for cybersecurity merges security architecture models and security economics. By identifying the most efficient routes for gaining access to assets from an attacker's viewpoint, an organization can optimize its defenses along these routes. The well-understood concept of na...... of navigation makes it easier to motivate and explain security investment to a wide audience, encouraging strategic security decisions....

Navigational Strategies of Migrating Monarch Butterflies

Science.gov (United States)

2014-11-10

AFRL-OSR-VA-TR-2014-0339 NAVIGATIONAL STRATEGIES OF MIGRATING MONARCH BUTTERFLIES Steven Reppert UNIVERSITY OF MASSACHUSETTS Final Report 11/10/2014...Final Progress Statement to (Dr. Patrick Bradshaw) Contract/Grant Title: Navigational Strategies of Migrating Monarch Butterflies Contract...Grant #: FA9550-10-1-0480 Reporting Period: 01-Sept-10 to 31-Aug-14 Overview of accomplishments: Migrating monarch butterflies (Danaus

Control of internal packing seal clearances considering for shaft behavior during steam turbine operation

Energy Technology Data Exchange (ETDEWEB)

Pack, Min Sik; Lee, Si Yeon; Choi, Sung Choul; Lee, Jae Geun [Korea Plant Service and Engineering Co., Ltd., Seongnam (Korea, Republic of); Yang, Bo Suk [Pukyong National Univ., Busan (Korea, Republic of)

2004-07-01

This paper presents the characteristics of internal clearances for the interstage of blades and shaft gland seals on the steam turbine which are installed in tandem compound. Internal clearances was changed when the rotor turned in the cylindrical sleeve bearing due to the generation of oil film wedge. This presented concern is very useful to prevent the rubbing damage of seal edge between the fixed and moving parts in steam turbine due to the misalignment at the rotating and stationary parts. This method is applied for the unbalanced clearances distribution to the left and right sides in the turbine casing. A considerable amount of unbalanced clearances distribution trend is determined according to the rotating speed of rotor, size and type of journal bearing, oil viscosity, surface roughness of bearing and shaft, oil temperature, oil pressure and bearing load.

PERFORMANCE CHARACTERISTIC MEMS-BASED IMUs FOR UAVs NAVIGATION

Directory of Open Access Journals (Sweden)

H. A. Mohamed

2015-08-01

Full Text Available Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK, and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS signal outage.

Model-base visual navigation of a mobile robot

International Nuclear Information System (INIS)

Roening, J.

1992-08-01

The thesis considers the problems of visual guidance of a mobile robot. A visual navigation system is formalized consisting of four basic components: world modelling, navigation sensing, navigation and action. According to this formalization an experimental system is designed and realized enabling real-world navigation experiments. A priori knowledge of the world is used for global path finding, aiding scene analysis and providing feedback information to the close the control loop between planned and actual movements. Two world models were developed. The first approach was a map-based model especially designed for low-level description of indoor environments. The other was a higher level and more symbolic representation of the surroundings utilizing the spatial graph concept. Two passive vision approaches were developed to extract navigation information. With passive three- camera stereovision a sparse depth map of the scene was produced. Another approach employed a fish-eye lens to map the entire scene of the surroundings without camera scanning. The local path planning of the system is supported by three-dimensional scene interpreter providing a partial understanding of scene contents. The interpreter consists of data-driven low-level stages and a model-driven high-level stage. Experiments were carried out in a simulator and test vehicle constructed in the laboratory. The test vehicle successfully navigated indoors

Performance Characteristic Mems-Based IMUs for UAVs Navigation

Science.gov (United States)

Mohamed, H. A.; Hansen, J. M.; Elhabiby, M. M.; El-Sheimy, N.; Sesay, A. B.

2015-08-01

Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs) are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS) or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK), and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS) signal outage.

Effects of cigarette smoking on I-123 IMP clearance from the lung

International Nuclear Information System (INIS)

Katoh, Kunihiko; Takahashi, Tsuneo

1990-01-01

N-isopropyl-p-I-123-iodoamphetamine (I-123 IMP), originally developed as a brain scanning agent, is also taken up by the lung. To evaluate the cigarette smoking on the uptake of IMP by the lung, we studied I-123 IMP clearance from the lung on 14 volunteers; 5 non-smokers and 9 smokers. After the injection of 111 MBq (3mCi) of I-123 IMP into the medial cubital vein, the time-activity curve for 60 minutes and the regional activity using 1 frame per minute and a 64 x 64 matrix was obtained. I-123 IMP clearance curve was described as follows: C(t)=A 1 e -k1t +A 2 e -k2t (A 1 , A 2 : intercepts, and k 1 , k 2 : slopes of the exponential components). I-123 IMP clearance was delayed in smokers, and k 2 was smaller in smokers. Also a significant correlations between k 1 , k 2 , and the number of cigarettes smoked per day were found. In conclusion, this study suggests that the delayed clearance and retention of I-123 IMP in the lung indicate the lung metabolic disorders due to cigarette smoking. (author)

Effect of Guide Vane Clearance Gap on Francis Turbine Performance

Directory of Open Access Journals (Sweden)

Ravi Koirala

2016-04-01

Full Text Available Francis turbine guide vanes have pivoted support with external control mechanism, for conversion of pressure to kinetic energy and to direct them to runner vanes. This movement along the support is dependent on variation of load and flow (operating conditions. Small clearance gaps between facing plates and the upper and lower guide vane tips are available to aid this movement, through which leakage flow occurs. This secondary flow disturbs the main flow stream, resulting performance loss. Additionally, these increased horseshoe vortex, in presence of sand, when crosses through the gaps, both the surfaces are eroded. This causes further serious effect on performance and structural property by increasing gaps. This paper discusses the observation of the severity in hydropower plants and effect of clearance gaps on general performance of the Francis turbine through computational methods. It also relates the primary result with the empirical relation for leakage flow prediction. Additionally, a possible method to computationally estimate thickness depletion has also been presented. With increasing clearance gap, leakage increases, which lowers energy conversion and turbine efficiency along with larger secondary vortex.

Impairment of aminopyrine clearance in aspirin-damaged canine gastric mucosa

International Nuclear Information System (INIS)

Miller, T.A.; Henagan, J.M.; Loy, T.M.

1983-01-01

Using an in vivo canine chambered stomach preparation, the clearance of [ 14 C]aminopyrine across mucosa when intravenously infused and the back-diffusion of this substance from gastric lumen to mucosa when topically applied to gastric epithelium were evaluated in aspirin-damaged gastric epithelium. In mucosa damaged by either 20 mM or 40 mM aspirin, the recovery of [ 14 C]aminopyrine, when topically mixed with acid (pH . 1.1) perfusate solution, was not significantly different from nondamaged control mucosa. In addition, the degree of ''trapping'' of this substance from back-diffusion was not different in damaged mucosa from that observed in nondamaged epithelium. In contrast, when [ 14 C]aminopyrine was intravenously infused, its clearance was significantly impaired in aspirin-damaged mucosa when compared with control studies, as evidenced by the increased ''trapping'' of this substance in injured epithelium. These findings indicate that movement of aminopyrine from plasma to gastric lumen is impaired in damaged epithelium, making the aminopyrine clearance technique an unreliable method to accurately measure absolute gastric blood flow in this experimental setting

22 CFR 401.25 - Government brief regarding navigable waters.

Science.gov (United States)

2010-04-01

... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Government brief regarding navigable waters. 401... PROCEDURE Applications § 401.25 Government brief regarding navigable waters. When in the opinion of the Commission it is desirable that a decision should be rendered which affects navigable waters in a manner or...

Numerical investigation of tip clearance cavitation in Kaplan runners

Science.gov (United States)

Nikiforova, K.; Semenov, G.; Kuznetsov, I.; Spiridonov, E.

2016-11-01

There is a gap between the Kaplan runner blade and the shroud that makes for a special kind of cavitation: cavitation in the tip leakage flow. Two types of cavitation caused by the presence of clearance gap are known: tip vortex cavitation that appears at the core of the rolled up vortex on the blade suction side and tip clearance cavitation that appears precisely in the gap between the blade tip edge and the shroud. In the context of this work numerical investigation of the model Kaplan runner has been performed taking into account variable tip clearance for several cavitation regimes. The focus is put on investigation of structure and origination of mechanism of cavitation in the tip leakage flow. Calculations have been performed with the help of 3-D unsteady numerical model for two-phase medium. Modeling of turbulent flow in this work has been carried out using full equations of Navier-Stokes averaged by Reynolds with correction for streamline curvature and system rotation. For description of this medium (liquid-vapor) simplification of Euler approach is used; it is based on the model of interpenetrating continuums, within the bounds of this two- phase medium considered as a quasi-homogeneous mixture with the common velocity field and continuous distribution of density for both phases. As a result, engineering techniques for calculation of cavitation conditioned by existence of tip clearance in model turbine runner have been developed. The detailed visualization of the flow was carried out and vortex structure on the suction side of the blade was reproduced. The range of frequency with maximum value of pulsation was assigned and maximum energy frequency was defined; it is based on spectral analysis of the obtained data. Comparison between numerical computation results and experimental data has been also performed. The location of cavitation zone has a good agreement with experiment for all analyzed regimes.

14 CFR 99.17 - Deviation from flight plans and ATC clearances and instructions.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Deviation from flight plans and ATC clearances and instructions. 99.17 Section 99.17 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... TRAFFIC General § 99.17 Deviation from flight plans and ATC clearances and instructions. (a) No pilot may...

Mobile Robot Navigation

DEFF Research Database (Denmark)

Andersen, Jens Christian

2007-01-01

the current position to a desired destination. This thesis presents and experimentally validates solutions for road classification, obstacle avoidance and mission execution. The road classification is based on laser scanner measurements and supported at longer ranges by vision. The road classification...... is sufficiently sensitive to separate the road from flat roadsides, and to distinguish asphalt roads from gravelled roads. The vision-based road detection uses a combination of chromaticity and edge detection to outline the traversable part of the road based on a laser scanner classified sample area....... The perception of these two sensors are utilised by a path planner to allow a number of drive modes, and especially the ability to follow road edges are investigated. The navigation mission is controlled by a script language. The navigation script controls route sequencing, junction detection, junction crossing...

Frequency of stone clearance after extracorporeal shockwave ...

African Journals Online (AJOL)

Objective: To determine the rate of stone clearance after extracorporeal shockwave lithotripsy (ESWL) for renal stones in adult patients with renal insufficiency. Subjects and methods: This is a cross-sectional descriptive study of 117 adult patients who underwent ESWL. The indications for ESWL were determined by the ...

Correlates of spontaneous clearance of hepatitis C virus in a Danish human immunodeficiency virus type 1 cohort

DEFF Research Database (Denmark)

Clausen, Louise Nygaard; Weis, Nina; Schønning, Kristian

2011-01-01

) 18-28) had cleared their HCV infection and 251 (77%; 95% CI 72-82) had a chronic infection. The clearance rate in HBsAg-positive individuals was 65%. Being female, HBsAg-positive, or belonging to HIV exposure groups IDU and MSM predicted higher HCV clearance rates (adjusted odds ratio (aOR) 1.8, 95......% CI 1-3.2; aOR 7.6, 95% CI 2.7-21; aOR 5.2, 1.2-23.5; and aOR 10.2, 95% CI 1.8-58, respectively). Race, acquired immunodeficiency syndrome (AIDS), and antiretroviral therapy were not associated with HCV clearance. Conclusions: The HCV clearance rate in this HIV-1 cohort was 23%. MSM and IDUs may have......Abstract Background: Around a quarter of individuals infected with hepatitis C virus (HCV) are spontaneously able to clear the virus. Correlates of spontaneous HCV clearance are not well established and the aim of this study was to characterize factors associated with spontaneous HCV clearance...

A model of metabolism and clearance of organic compounds from the respiratory tract

International Nuclear Information System (INIS)

Gerde, P.; Dahl, A.R.

1994-01-01

In cases where inhalants induce toxicity in the airway epithelium, the mechanism of absorption is an important determinant of target dose. Absorption of organic solutes in the lungs occurs mainly by two consecutive mechanisms; molecular diffusion drives the chemicals into the tissues, and blood perfusion of the tissues removes the chemicals into the systemic circulation. Solutes having lipophilicities ranging from equally soluble in lipids and water to moderately more lipid-soluble are limited by the perfusion during clearance from the lungs. The perfusion-limited solute enters the blood circulation from all regions of the lungs within minutes and is distributed to other organs via the systemic circulation. In contrast, clearance of highly lipophilic toxicants, such as benzo(a)pyrene, from the lungs is diffusion-limited. The limiting process refers to the slowest transport mechanism of either perfusion or diffusion. Because of the short distance from the surface of the alveolar region to the capillary network, diffusion-limited clearance of highly lipophilic solutes occurs within minutes. In the thicker epithelium of the conducting airways, however, clearance may take hours. The purpose of the current modeling effort was to encompass both mechanisms of clearance in a single model in order to explore the influence of toxicant lipophilicity and local metabolism on the dosimetry at the airway portal-of-entry

Hepatic and muscle clearance of physostigmine in the rat after i.v. administration

International Nuclear Information System (INIS)

Somani, S.M.; Unni, L.K.

1986-01-01

This study presents a method to calculate the extraction ratio (ER) from in vivo time course of liver metabolism using the physiological and pharmacokinetic parameters such as plasma flow rate, partition coefficient of drug between tissue and plasma and the elimination rate constant from tissues. Rats were administered 3 H-physostigmine (Phy), 100 μg/kg i.v.; and were sacrificed at various times. Tissues were removed and Phy and its metabolites were determined by HPLC. Half-life of Phy in liver and muscle was 24 and 20 min, respectively. ER of Phy in liver was .71 which showed a slight decrease at 10 min. Muscle ER was found to be .347 up to 5 min. Hepatic clearance was calculated to be 23.08 ml/min/kg (34.9% of systemic clearance) and the intrinsic clearance was 83.73 ml/min/kg which indicates that the changes in blood flow to the liver can cause a variation in the systematic clearance. Percentage dose of Phy retained in muscle was maximum and the clearance was 5.2 ml/min/kg suggesting that muscle might be acting as a storage depot for Phy prolonging the pharmacological effects. About 30-40% of radioactivity in the liver could not be washed off by 10% TCA or organic solvents indicating the irreversible binding of drug or metabolite to liver macromolecule

Navigating nuclear science: Enhancing analysis through visualization

Energy Technology Data Exchange (ETDEWEB)

Irwin, N.H.; Berkel, J. van; Johnson, D.K.; Wylie, B.N.

1997-09-01

Data visualization is an emerging technology with high potential for addressing the information overload problem. This project extends the data visualization work of the Navigating Science project by coupling it with more traditional information retrieval methods. A citation-derived landscape was augmented with documents using a text-based similarity measure to show viability of extension into datasets where citation lists do not exist. Landscapes, showing hills where clusters of similar documents occur, can be navigated, manipulated and queried in this environment. The capabilities of this tool provide users with an intuitive explore-by-navigation method not currently available in today`s retrieval systems.

The Programmer's Guide to iSeries Navigator

CERN Document Server

Touhy, Paul

2012-01-01