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Sample records for cber 510k clearances

  1. 76 FR 45825 - Center for Devices and Radiological Health 510(k) Clearance Process; Institute of Medicine Report...

    Science.gov (United States)

    2011-08-01

    ...] Center for Devices and Radiological Health 510(k) Clearance Process; Institute of Medicine Report... Drug Administration (FDA) is requesting comments on the Institute of Medicine (IOM) report entitled... conclusions or recommendations contained within the report. FDA may, in the future, take additional measures...

  2. Center for Biologics Evaluation and Research (CBER)

    Data.gov (United States)

    Federal Laboratory Consortium — CBER is the Center within FDA that regulates biological products for human use under applicable federal laws, including the Public Health Service Act and the Federal...

  3. 76 FR 50230 - Center for Devices and Radiological Health 510(k) Clearance Process; Recommendations Proposed in...

    Science.gov (United States)

    2011-08-12

    ..., from 8:30 a.m. to 5 p.m. Submit electronic and written comments by September 30, 2011. Location: The public meeting will be held at the Silver Spring Hilton Hotel, 8727 Colesville Rd., Silver Spring, MD...

  4. 21 CFR 807.92 - Content and format of a 510(k) summary.

    Science.gov (United States)

    2010-04-01

    ... Section 807.92 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... time as FDA issues a determination of substantial equivalence. All 510(k) summaries shall contain the... description, where appropriate, of the patient population for which the device is intended. If the indication...

  5. 76 FR 44935 - Draft Guidance for Industry and Food and Drug Administration Staff; 510(k) Device Modifications...

    Science.gov (United States)

    2011-07-27

    ...] Draft Guidance for Industry and Food and Drug Administration Staff; 510(k) Device Modifications: Deciding When To Submit a 510(k) for a Change to an Existing Device; Availability AGENCY: Food and Drug... technologies, and to provide greater clarity about changes that do not trigger the need for a new premarket...

  6. 78 FR 14097 - Pulse Oximeters-Premarket Notification Submissions [510(k)s]; Guidance for Industry and Food and...

    Science.gov (United States)

    2013-03-04

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2007-D-0205 (Formerly 2007D-0252)] Pulse Oximeters--Premarket Notification Submissions [510(k)s]; Guidance for Industry and Food and Drug Administration Staff; Availability AGENCY: Food and Drug Administration, HHS. ACTION...

  7. Next generation hyper resolution wide swath and multi-channel optical payload for CBERS series

    Science.gov (United States)

    Wang, Weigang

    2017-11-01

    The China-Brazilian Earth Resources Satellite (CBERS) program, (also called ZY-1) the result of a space technology agreement between China and Brazil, was officially signed in 1988 after the first joint work report produced by National Institute for Space Research (INPE) and the Chinese Academy of Space Technology (CAST). During the 26 years of its existence, the program of cooperation between China and Brazil in space has achieved the successful launch of three satellites. It has become a unique example of cooperation in cutting edge technology between emerging nations. CBERS satellite is the first generation data-transferring remote sensing satellite developed by China. CBERS satellite data are widely applied to crop yield estimation, exploration of land and resources, urban planning, environmental protection and monitoring, disaster reduction, and other fields. CBERS series is just like Landsat series of USA and SPOT series of France.

  8. Exterior orientation of CBERS-2B imagery using multi-feature control and orbital data

    Science.gov (United States)

    Marcato Junior, J.; Tommaselli, A. M. G.

    2013-05-01

    The major contribution of this paper relates to the practical advantages of combining Ground Control Points (GCPs), Ground Control Lines (GCLs) and orbital data to estimate the exterior orientation parameters of images collected by CBERS-2B (China-Brazil Earth Resources Satellite) HRC (High-resolution Camera) and CCD (High-resolution CCD Camera) sensors. Although the CBERS-2B is no longer operational, its images are still being used in Brazil, and the next generations of the CBERS satellite will have sensors with similar technical features, which motivates the study presented in this paper. The mathematical models that relate the object and image spaces are based on collinearity (for points) and coplanarity (for lines) conditions. These models were created in an in-house developed software package called TMS (Triangulation with Multiple Sensors) with multi-feature control (GCPs and GCLs). Experiments on a block of four CBERS-2B HRC images and on one CBERS-2B CCD image were performed using both models. It was observed that the combination of GCPs and GCLs provided better bundle block adjustment results than conventional bundle adjustment using only GCPs. The results also demonstrate the advantages of using primarily orbital data when the number of control entities is reduced.

  9. 78 FR 100 - Guidance for Industry and Food and Drug Administration Staff; Refuse To Accept Policy for 510(k)s...

    Science.gov (United States)

    2013-01-02

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2012-D-0523] Guidance for Industry and Food and Drug Administration Staff; Refuse To Accept Policy for 510(k)s; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug...

  10. First in-Flight Radiometric Calibration of MUX and WFI on-Board CBERS-4

    Directory of Open Access Journals (Sweden)

    Cibele Pinto

    2016-05-01

    Full Text Available Brazil and China have a long-term joint space based sensor program called China-Brazil Earth Resources Satellite (CBERS. The most recent satellite of this program (CBERS-4 was successfully launched on 7 December 2014. This work describes a complete procedure, along with the associated uncertainties, used to calculate the in-flight absolute calibration coefficients for the sensors Multispectral Camera (MUX and Wide-Field Imager (WFI on-board CBERS-4. Two absolute radiometric calibration techniques were applied: (i reflectance-based approach and (ii cross-calibration method. A specific site at Algodones Dunes region located in the southwestern portion of the United States of America was used as a reference surface. Radiometric ground and atmospheric measurements were carried out on 9 March 2015, when CBERS-4 passed over the region. In addition, a cross-calibration between both MUX and WFI on-board CBERS-4 and the Operational Land Imager (OLI on-board Landsat-8 was performed using the Libya-4 Pseudo Invariant Calibration Site. The gain coefficients are now available: 1.68, 1.62, 1.59 and 1.42 for MUX and 0.379, 0.498, 0.360 and 0.351 for WFI spectral bands blue, green, red and NIR, respectively, in units of (W/(m2·sr·μm/DN. These coefficients were determined with uncertainties lower than 3.5%. As a validation of these radiometric coefficients, cross-calibration was also undertaken. An evaluation of radiometric consistency was performed between the two instruments (MUX and WFI on-board CBERS-4 and with the well calibrated Landsat-7 ETM+. Results show that the reflectance values match in all the analogous spectral bands within the specified calibration uncertainties.

  11. Discriminação de variedades de citros em imagens CCD/CBERS-2 Discrimination of citrus varieties using CCD/CBERS-2 satellite imagery

    Directory of Open Access Journals (Sweden)

    Ieda Del'Arco Sanches

    2008-02-01

    Full Text Available O presente trabalho teve o objetivo de avaliar as imagens CCD/CBERS-2 quanto à possibilidade de discriminarem variedades de citros. A área de estudo localiza-se em Itirapina (SP e, para este estudo, foram utilizadas imagens CCD de três datas (30/05/2004, 16/08/2004 e 11/09/2004. Um modelo que integra os elementos componentes da cena citrícola sensoriada é proposto com o objetivo de explicar a variabilidade das respostas das parcelas de citros em imagens orbitais do tipo CCD/CBERS-2. Foram feitas classificações pelos algoritmos Isoseg e Maxver e, de acordo com o índice kappa, concluiu-se que é possível obterem-se exatidões qualificadas como muito boas, sendo que as melhores classificações foram conseguidas com imagens da estação seca.This paper was aimed at evaluating the possibility of discriminating citrus varieties in CCD imageries from CBERS-2 satellite ("China-Brazil Earth Resouces Satellite". The study area is located in Itirapina, São Paulo State. For this study, three CCD images from 2004 were acquired (May 30, August 16, and September 11. In order to acquire a better understanding and for explaining the variability of the spectral behavior of the citrus areas in orbital images (like as the CCD/CBERS-2 images a model that integrates the elements of the citrus scene is proposed and discussed. The images were classified by Isoseg and MaxVer classifiers. According to kappa index, it was possible to obtain classifications qualified as 'very good'. The best results were obtained with the images from the dry season.

  12. Deviations in CBERS-4 Satellite Direction Components From The Electromagnetic Disturbance of Communication Antennas

    Science.gov (United States)

    Heilmann, A.; Fernandes, C.

    2017-10-01

    The CBERS-4 is a low Earth orbit satellite, with a set of antennas S-band/UHF for communication almost omni-direcional. For the electromagnetic radiation from transmission antennas, was developed a model of electromagnetic disturbance considering the antennas theory and the laws of the conservation energy-momentum. Was propagated the orbit of the CBERS-4 satellite considering your state vector from the March 14, 2016, at 11h 14m 15.23s using the equation of motion in the form of cartesian components. From the state vector of the CBERS-4 satellite was possible to propagate the orbit for different periods, without disturbance (considering just the problem of two bodies) and with a disturbance of electromagnetic origin. The model of reaction of electromagnetic acceleration on the satellite depends on only the type of antenna. Quadrifilar and parabolic propeller antennas were considered in this paper. Using the equation of motion of the satellite based on the method of Runge-Kutta of fourth and fifth degree, the effect disturber this modeling was applied on the CBERS-4 considering the mass of satellite, characteristics of antenna, power irradiated and gain maximum of antenna. The final analysis discusses the values of components in the direction (radial, cross and normal) and the coordinates X-Y-Z considering the case disturbed to both antennas.

  13. Evaluation of land use classification accuracy based upon TM and CBERS-02B HR data fusion

    Science.gov (United States)

    Liu, Guifang; Lu, Heli

    2010-11-01

    Data fusions from SAR and TM, SPOT and TM, ASTER and TM, MODIS and ETM, etc are the common methods. But that from TM and CBERS-02B is rare. With HR camera working in September 19th 2007, Chinese-Brazil Earth Resources Satellite 02B (CBERS-02B) became the first civilian high-resolution satellite in China. It could provide 2.36m panchromatic image which is better to Landsat TM. Meanwhile the spectral resolution of TM is better than CBERS-02B. So it's a good idea to take advantage of benefits from CBERS-02B HR and TM through data fusion. In this study, images of TM and CBERS-02B HR in 2007 were used as data sources. After image registration and noiseremoval process, data fusion methods of IHS and PCA were adopted. Then unsupervised classification and supervised classification were used for land use classification. Finally, classification accuracy between original image and fusion image was compared and evaluated. The result shows: (1) Compared with original TM or CBERS-02B HR image, the fusion image not only retains abundance spectrum but also enhances the object details. Residential texture, lake morphological, the relative position between roads, industrial and mining sites, etc, was identified easily. (2) Results from IHS and PCA are different. IHS image had higher spatial resolution but more spectral distortion. Spectral differences between some objects became smaller and classification accuracy was lower. Supervised classification accuracy assessment shows that overall Kappa index and overall land use classification accuracy decreased by 0.237 and 11% respectively. Meanwhile PCA image not only had high spatial resolution, but also smaller spectral distortion. Different land use / cover types can be better distinguished. (3) Disadvantages of low spatial resolution in TM and single color in CBERS-02B HR image are overcome in PCA fusion image to a certain extent. In this research under supervised classification in PCA image Kappa index of farm land, forest land and

  14. Assessing the Relative Ecological Importance and Deforestation Risks of Unprotected Areas in Western Brazil Using Landsat, CBERS and Quantum GIS

    Science.gov (United States)

    Smith, A.; Sevilla, C.; Lanclos, A.; Carson, C.; Larson, J.; Sankaran, M.; Saad, M.

    2012-12-01

    In addition to understanding Brazilian policies and currently utilized methodologies, the measurement of the impacts of deforestation is essential for enhancing techniques to reduce deforestation in the future. Adverse impacts of deforestation include biodiversity loss, increased carbon dioxide emissions, and a reduced rate of evapotranspiration, all of which contribute directly or indirectly to global warming. With the continual growth in population in developing countries such as Brazil, increased demands are placed on infrastructural development and food production. As a result, forested areas are cleared for agricultural production. Recently, exploration for hydrocarbons in Western Brazil has also intensified as a means to stimulate the economy, as abundant oil and gas is believed to be found in these regions. Unfortunately, hydrocarbon-rich regions of Western Brazil are also home to thousands of species. Many of these regions are as of yet untapped but are at risk of ecological disruption as a result of impending human activity. This project utilized Landsat 5 TM to monitor deforestation in a subsection of the Brazilian states of Rondônia and Amazonas. A risk map identifying areas susceptible to future deforestation, based on factors such as proximity to roads, bodies of water, cities, and proposed hydrocarbon activities such as pipeline construction, was created. Areas at higher risk of clearance were recommended to be a target for enhanced monitoring and law enforcement. In addition, an importance map was created based on biodiversity and location of endangered species. This map was used to identify potential areas for future protection. A Chinese-Brazilian satellite, CBERS 2B CCD was also utilized for comparison. The NDVI model was additionally replicated in Quantum GIS, an open source software, so that local communities and policymakers could benefit without having to pay for expensive ArcGIS software. The capabilities of VIIRS were also investigated to

  15. The "déjà vu effect:" evaluation of United States medical device legislation, regulation, and the Food and Drug Administration's contentious 510(k) program.

    Science.gov (United States)

    Bauman, Jordan

    2012-01-01

    With the Medical Device Amendments of 1976, Congress granted FDA authority to regulate medical devices by implementing a risk-based regulatory framework. Several years prior to this legislation, the Cooper Committee reviewed the medical device regulatory landscape and uncovered weaknesses that could be detrimental to public health. However, only after several high-profile incidents involving unsafe medical devices did Congress respond with strong legislation. Since 1976, additional medical device legislative revisions have been enacted to address deficiencies highlighted by various groups representing Congress, FDA, and industry. A repetitive conclusion from these groups has been that the 510(k) program is incapable of serving as a premarket evaluation of safety and effectiveness under the existing statutory framework. However, these legislative revisions did not change the statutory framework despite these repeated findings. In 2009, CDRH convened separate groups to again review the 510(k) program. While more comprehensive than previous initiatives, the observed deficiencies and the proposed recommendations are remarkably similar to those identified by their predecessors. This cyclical review of the medical device regulatory landscape whereby the same observations and recommendations are repeated yet the output of such review does not yield major legislative revision of the existing statutory framework can be described as the "déjà vu effect." This will continue unless Congress enacts legislation that implements a new statutory framework with a different standard other than substantial equivalence. In the past, Congress has implemented major legislation only after a public health crisis. Hopefully this will not be the driving force in the future.

  16. Mucociliary clearance

    DEFF Research Database (Denmark)

    Munkholm, Mathias; Mortensen, Jann

    2014-01-01

    Mucociliary clearance has long been known to be a significant innate defence mechanism against inhaled microbes and irritants. Important knowledge has been gathered regarding the anatomy and physiology of this system, and in recent years, extensive studies of the pathophysiology related to lung...... pharmacological interventions on clearance rate, to study the importance of defective mucus clearance in different lung diseases or as a diagnostic tool in the work-up of patients with recurrent airway diseases. The aim of this review is to provide an overview of the anatomy, physiology, pathophysiology...... diseases characterized by defective mucus clearance have resulted in a variety of therapies, which might be able to enhance clearance from the lungs. In addition, ways to study in vivo mucociliary clearance in humans have been developed. This can be used as a means to assess the effect of different...

  17. STRIPING NOISE REMOVAL OF IMAGES ACQUIRED BY CBERS 2 CCD CAMERA SENSOR

    Directory of Open Access Journals (Sweden)

    E. Amraei

    2014-10-01

    Full Text Available CCD Camera is a multi-spectral sensor that is carried by CBERS 2 satellite. Imaging technique in this sensor is push broom. In images acquired by the CCD Camera, some vertical striping noise can be seen. This is due to the detectors mismatch, inter detector variability, improper calibration of detectors and low signal-to-noise ratio. These noises are more profound in images acquired from the homogeneous surfaces, which are processed at level 2. However, the existence of these noises render the interpretation of the data and extracting information from these images difficult. In this work, spatial moment matching method is proposed to modify these images. In this method, the statistical moments such as mean and standard deviation of columns in each band are used to balance the statistical specifications of the detector array to those of reference values. After the removal of the noise, some periodic diagonal stripes remain in the image where their removal by using the aforementioned method seems impossible. Therefore, to omit them, frequency domain Butterworth notch filter was applied. Finally to evaluate the results, the image statistical moments such as the mean and standard deviation were deployed. The study proves the effectiveness of the method in noise removal.

  18. Orientação de imagens CBERS-2B usando o modelo rigoroso de colinearidade com dados orbitais

    Directory of Open Access Journals (Sweden)

    José Marcato Junior

    Full Text Available Atualmente, o imageamento orbital é uma das principais técnicas de coleta de informações geoespaciais. Embora os sistemas orbitais sejam equipados com sensores de orientação direta (GNSS, giroscópios, sensores de estrelas, dentre outros, nem sempre as imagens corrigidas a partir dos dados (efemérides e atitude provenientes destes sensores apresentam a acurácia requerida para certas aplicações. Uma das alternativas para solucionar este problema é a orientação dessas imagens considerando as informações de órbita (efemérides e atitude com o uso adicional de pontos de apoio. O objetivo principal deste trabalho consiste em avaliar experimentalmente o modelo de colinearidade com dados orbitais no processo de orientação de imagens CBERS-2B. Este modelo foi implementado no programa TMS (Triangulação MultiSsensor, seguindo a abordagem de triangulação multissensor. Foram realizados experimentos com imagens do nível 1 (com apenas correção radiométrica coletadas pelos sensores CCD e HRC. Nos casos estudados verificou-se que a utilização das informações de órbita possibilita a orientação de imagens CBERS-2B com um número reduzido de pontos de apoio.

  19. AVALIAÇÃO DAS IMAGENS CBERS/CCD PARA O MAPEAMENTO DE AREAIS NO SUDOESTE DE GOIÁS

    Directory of Open Access Journals (Sweden)

    Marluce Silva Sousa

    2007-06-01

    Full Text Available O objetivo deste trabalho foi o de aplicar diferentes técnicasde transformação em duas imagens CBERS, dosperíodos seco e chuvoso, que permitissem realçar emapear as manchas de Neossolos Quartzarênicos, semcobertura vegetal (areais, da bacia do Ribeirão Sujo,município de Serranópolis/GO. Revisaram-se bibliografiassobre comportamento espectral de solos arenosose trabalhos relacionados à avaliação de áreas degradadas.Utilizaram-se três métodos de transformaçãode imagens para os dois períodos com a finalidade demapear os areais: o modelo linear de mistura espectral,o índice de vegetação da diferença normalizada (NDVI ea análise por componentes principais. Verificou-se queas imagens do período chuvoso ressaltaram melhor osareais em relação aos vários tipos de cobertura da terrae que a técnica que apresentou o melhor resultado para omapeamento dos areais foi a classificação supervisionadadas bandas 2, 3 e 4 do sensor CDD/CBERS.

  20. Creatinine clearance test

    Science.gov (United States)

    Serum creatinine clearance; Kidney function - creatinine clearance; Renal function - creatinine clearance ... Chernecky CC, Berger BJ. Creatinine clearance - serum and urine. ... Diagnostic Procedures . 6th ed. St Louis, MO: Elsevier Saunders; ...

  1. CCD CBERS and ASTER data in dasometric characterization of Pinus radiata D. Don (north-western Spain

    Directory of Open Access Journals (Sweden)

    Eva Sevillano-Marco

    2013-03-01

    Full Text Available A Chinese-Brazilian Earth Resources Satellite (CBERS and an Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER scenes coupled with ancillary georeferenced data and field survey were employed to examine the potential of the remote sensing data in stand basal area, volume and aboveground biomass assessment over large areas of Pinus radiata D. Don plantations in Northwestern Spain. Statistical analysis proved that the near infrared band and the shade fraction image showed significant correlation coefficients with all stand variables considered. Predictive models were accordingly selected and utilized to undertake the spatial distribution of stand variables in radiata stands delimited by the National Forestry Map. The study reinforces the potentiality of remote sensing techniques in a cost-effective assessment of forest systems.

  2. Identifying Spatial Units of Human Occupation in the Brazilian Amazon Using Landsat and CBERS Multi-Resolution Imagery

    Directory of Open Access Journals (Sweden)

    Maria Isabel Sobral Escada

    2012-01-01

    Full Text Available Every spatial unit of human occupation is part of a network structuring an extensive process of urbanization in the Amazon territory. Multi-resolution remote sensing data were used to identify and map human presence and activities in the Sustainable Forest District of Cuiabá-Santarém highway (BR-163, west of Pará, Brazil. The limits of spatial units of human occupation were mapped based on digital classification of Landsat-TM5 (Thematic Mapper 5 image (30m spatial resolution. High-spatial-resolution CBERS-HRC (China-Brazil Earth Resources Satellite-High-Resolution Camera images (5 m merged with CBERS-CCD (Charge Coupled Device images (20 m were used to map spatial arrangements inside each populated unit, describing intra-urban characteristics. Fieldwork data validated and refined the classification maps that supported the categorization of the units. A total of 133 spatial units were individualized, comprising population centers as municipal seats, villages and communities, and units of human activities, such as sawmills, farmhouses, landing strips, etc. From the high-resolution analysis, 32 population centers were grouped in four categories, described according to their level of urbanization and spatial organization as: structured, recent, established and dependent on connectivity. This multi-resolution approach provided spatial information about the urbanization process and organization of the territory. It may be extended into other areas or be further used to devise a monitoring system, contributing to the discussion of public policy priorities for sustainable development in the Amazon.

  3. Airway Clearance Techniques (ACTs)

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  5. Análise de mapas de represas publicados na web usando imagens orbitais CCD/CBERS no estado de Minas Gerais Analysis of dams maps published on the web by using orbital CCD/CBERS images in Minas Gerais State, Brazil

    Directory of Open Access Journals (Sweden)

    Elizabeth Ferreira

    2010-02-01

    Full Text Available Neste trabalho, bancos de dados públicos e gratuitos disponíveis na World Wide Web (WEB foram utilizados para avaliar as áreas das superfícies dos espelhos d'água das represas de Furnas e do Funil, no Estado de Minas Gerais. O objetivo foi comparar as informações obtidas nos bancos da WEB com os valores das áreas calculadas a partir de imagens do sensor CCD a bordo dos satélites CBERS2 e CBERS2B. A área da represa de Furnas obtida a partir das imagens CCD/CBERS2B, ano 2008, foi de 1.138 km², mas nos bancos de dados consultados esta área estava entre 1.182 e 1.503 km². A represa do Funil, construída em 2003, com superfície de espelho d'água de 29,37 km² e uma ilha com área de 1,93 km² não aparecem nos bancos Atlas, Geominas, IGAM e IBGE. Os resultados mostraram algumas discrepâncias nos bancos de dados publicados na WEB, tais como diferenças em áreas e supressão ou extrapolação de limites do espelho d'água. Concluiu-se que, até o momento, os responsáveis por algumas publicações de bancos de dados no Estado de Minas Gerais não tiveram rigor suficiente com as atualizações. As imagens CCD/CBERS, que também são dados públicos disponíveis na WEB, mostraram ser produtos adequados para verificar, atualizar e melhorar as informações publicadas.In this work some public databases from the World Wide Web (WEB were used to find the area of the Furnas and Funil Dams in Minas Gerais State. The purpose of this work was to compare the WEB public databases values and the real values obtained from the CCD camera images on board CBERS2 and CBERS2B satellites. The Furnas Dam area obtained from CCD/ CBERS2B images, in 2008, was 1.138 km², but in the consulted databases this area ranged from 1.182 to 1.503 km². The dam of the Funil, built in 2003, with a water surface of 29.37 km² and an island with 1.93 km² area, did not appear in Atlas, Geominas, IGAM and IBGE databases. The results revealed some problems in the WEB public

  6. The use of CBERS (China-Brazil Earth Resources Satellite to trace the dynamics of total suspended matter at an urbanized coastal area

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Colo Giannini

    Full Text Available ABSTRACT The distribution of organic and inorganic particles in the water column, or the total suspended matter (TSM, responds to local and remote oceanographic and meteorological processes, potentially impacting biogeochemical cycles. In shallow coastal areas, where particles have distinct origins and compositions and vary in different time scales, the use of remote sensing tools for monitoring and tracing this material is highly encouraged due to the high temporal and spatial data resolution. The objective of this work was to understand the variability of in situ TSM at Santos Bay (Southeastern Brazil and its response to oceanographic and meteorological conditions. We also aimed to verify the applicability of the satellite data from CBERS-2 sensor in order to map the dynamics of TSM in this region. Our results have shown that the distribution of TSM in Santos Bay varied consistently with winds, currents and tidal cycles, with significant relationships emphasizing the role of south-western winds and spring tides. Neap tides and eastern winds, along with rainfall, play an important role in the input of organic matter into the bay. In conclusion, our analyses showed that the main patterns observed in situ regarding the responses of TSM to the ocean-meteorological processes could be reproduced in the CBERS-2 satellite data, after simple and standard methods of images processing. TSM data retrieval from CBERS-2 or other satellite sensors were shown to be feasible, becoming an essential tool for synoptic observations of the composition and quality of water, especially at urbanized and impacted coastal areas.

  7. Airway Clearance Techniques (ACTs)

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  11. Security Clearance Tracking System

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

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  1. Airway Clearance Techniques (ACTs)

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    Full Text Available ... CFTR Modulator Therapies Mucus Thinners Nebulizer Care at Home Vascular Access Devices PICCs and Ports Partnerships for ... Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With CF Treatments and Therapies Airway Clearance ...

  2. Airway Clearance Techniques (ACTs)

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    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 ...

  3. Airway Clearance Techniques (ACTs)

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    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 ...

  4. Airway Clearance Techniques (ACTs)

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  5. Airway Clearance Techniques (ACTs)

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  6. Airway Clearance Techniques (ACTs)

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    Full Text Available ... Beall Therapeutics Development Award Patient Registry Care Center Data CF Patient Registry Reports Research Consortia CF Biomarker Consortium CFTR 3-D Structure Consortium CFTR Folding Consortium Mucociliary Clearance Consortium SUCCESS ...

  7. Airway Clearance Techniques (ACTs)

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    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 ...

  8. Generic Clearance Values

    International Nuclear Information System (INIS)

    Bossio, M.C.; Muniz, C.C.

    2010-01-01

    This paper analyzes the Generic Clearance Values established for natural and artificial radionuclides with the objective of evaluating their degree of conservatism in views of adopting them into the regulatory body. Generic clearance values for natural radionuclides have been chosen by experts judgments as the optimum boundary between, on the one hand, the ubiquitous unmodified soil concentrations and, on the other hand, activity concentrations in ores, mineral sands, industrial residues and wastes. For artificial radionuclides the clearance levels have been derived from the scenarios postulated in the document Safety Reports Series 44 of the IAEA considering quantitative exemption criteria. A set of 8 scenarios were postulated covering external, ingestion and inhalation exposure pathways. For each radionuclide, the generic clearance level was derived as the more restrictive value obtained from the scenarios, that is the lowest ratio between the applicable individual dose and the dose per unit activity concentration (Bq/g). The individual dose was calculated by a formula depending on each scenario and pathway, with different parameters, such as exposure time, dosimetric factors, dilution factor, density of the material, geometric factors, etc. It was concluded that the basis and parameters used for the derivation of the generic clearance levels are quite conservative and therefore its the adoption in Argentina has been recommended. It is expected that their implementation will contribute to optimize the regulatory management system. (authors) [es

  9. Generic clearance values

    International Nuclear Information System (INIS)

    Bossio, M.C.; Muniz, C.C.

    2009-01-01

    This paper analyzes the Generic Clearance Values established for natural and artificial radionuclides with the objective of evaluating their degree of conservatism in views of adopting them into the regulatory body. Generic clearance values for natural radionuclides have been chosen by experts judgments as the optimum boundary between, on one hand, the ubiquitous unmodified soil concentrations and, on the other hand, activity concentrations in ores, mineral sands, industrial residues and wastes. For artificial radionuclides the clearance levels have been derived from the scenarios postulated in the document 'Safety Reports Series Nr 44' of the IAEA considering quantitative exemption criteria. A set of 8 scenarios were postulated covering external, ingestion and inhalation exposure pathways. For each radionuclide, the generic clearance level was derived as the more restrictive value obtained from the scenarios, that is the lowest ratio between the applicable individual dose and the dose per unit activity concentration (Bq/g). The individual dose was calculated by a formula depending on each scenario and pathway, with different parameters, such as exposure time, dosimetric factors, dilution factor, density of the material, geometric factors, etc. It was concluded that the basis and parameters used for the derivation of the generic clearance levels are quite conservative and therefore its the adoption in Argentina has been recommended. It is expected that their implementation will contribute to optimize the regulatory management system. (author)

  10. 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 ...

  11. Airway Clearance Techniques (ACTs)

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    Full Text Available ... center. Carrier Testing for Cystic Fibrosis CFTR-Related Metabolic Syndrome (CRMS) How Babies Are Screened in IRT-Only ... Nutrition in Children and Adults Clinical Care Guidelines Nutrition in Pediatrics Clinical ... Airway Clearance Therapies Clinical Care Guidelines Chronic Medications to Maintain Lung ...

  12. Isotope determinations of renal clearance equivalent with physiological clearance measurements

    International Nuclear Information System (INIS)

    Junges, R.

    1983-01-01

    The concept of renal clearance in nuclear medicine describes the tubular secretion and glomerular filtration of a substance being removed from the blood plasma. The concept of clearance as used physiologically is rather wider and includes consideration of the outflow of the substances remained back in the kidneys. The present paper discusses clearance measurements as seen from a thermodynamic point of view, in which isotope clearances become equivalent with the physiological concept of clearance. In addition, it is possible to quantify each single step of the excretory function of each kidney separately. (orig.) [de

  13. Focus adjustment method for CBERS 3 and 4 satellites Mux camera to be performed in air condition and its experimental verification for best performance in orbital vacuum condition

    Science.gov (United States)

    Scaduto, Lucimara C. N.; Malavolta, Alexandre T.; Modugno, Rodrigo G.; Vales, Luiz F.; Carvalho, Erica G.; Evangelista, Sérgio; Stefani, Mario A.; de Castro Neto, Jarbas C.

    2017-11-01

    The first Brazilian remote sensing multispectral camera (MUX) is currently under development at Opto Eletronica S.A. It consists of a four-spectral-band sensor covering a 450nm to 890nm wavelength range. This camera will provide images within a 20m ground resolution at nadir. The MUX camera is part of the payload of the upcoming Sino-Brazilian satellites CBERS 3&4 (China-Brazil Earth Resource Satellite). The preliminary alignment between the optical system and the CCD sensor, which is located at the focal plane assembly, was obtained in air condition, clean room environment. A collimator was used for the performance evaluation of the camera. The preliminary performance evaluation of the optical channel was registered by compensating the collimator focus position due to changes in the test environment, as an air-to-vacuum environment transition leads to a defocus process in this camera. Therefore, it is necessary to confirm that the alignment of the camera must always be attained ensuring that its best performance is reached for an orbital vacuum condition. For this reason and as a further step on the development process, the MUX camera Qualification Model was tested and evaluated inside a thermo-vacuum chamber and submitted to an as-orbit vacuum environment. In this study, the influence of temperature fields was neglected. This paper reports on the performance evaluation and discusses the results for this camera when operating within those mentioned test conditions. The overall optical tests and results show that the "in air" adjustment method was suitable to be performed, as a critical activity, to guarantee the equipment according to its design requirements.

  14. Some Practical Payments Clearance Algorithms

    Science.gov (United States)

    Kumlander, Deniss

    The globalisation of corporations' operations has produced a huge volume of inter-company invoices. Optimisation of those known as payment clearance can produce a significant saving in costs associated with those transfers and handling. The paper revises some common and so practical approaches to the payment clearance problem and proposes some novel algorithms based on graphs theory and heuristic totals' distribution.

  15. 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.

  16. Aerial Refueling Clearance Process Guide

    Science.gov (United States)

    2014-08-21

    R. 4.9.3 Ball Valve/Leakage R. dhkARSAG DOC dtd. 6dec. 13; rev.21jan.14 Aerial Refueling Tanker/Receiver Clearance Compatibility Assessment Checklist...Clearance 9.6 Receiver Canopy/Boom Clearance 9.7 Lightning /Static Discharge Impact 10. Standards Compliance 10.1 STANAG 7191 Boom/ Recp. 10.2 AR...Type R. 4.9.1 Gate/Leakage R. 4.9.2 Poppet/Leakage R. 4.9.3 Ball Valve/Leakage R. 4.9.4 Other Leakage Source R. 4.10 Fuel Ingestion Hazard……... R. 5.0

  17. 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...... clearance data were independent of whether renal disease was of primarily glomerular or tubular origin and, further, were not influenced by long-term conventional antihypertensive treatment. 6. It is concluded that, even with a reduced kidney function, the data are compatible with the suggestion...... 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...

  18. 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...

  19. 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)

  20. Comparison of the endogenous creatinine clearance, the creatinin clearance calculated without urine collection and the isotope clearance

    International Nuclear Information System (INIS)

    Mohacsi, Gabor; Lang, Jenoe; Csernay, Laszlo; Sonkodi, Sandor; Orvostudomanyi Egyetem, Szeged

    1987-01-01

    Observations are reported relating to the endogenous creatinine clearance, the Tc-99m-EDTA-complex clearance and the creatinine clearance estimated via a selected mathematical formula, with special regard to the problems of renal insufficiency and the nephrotic syndrome. The activity applied was in the range of 3.7-7.4 MBq. It was observed that measurement of the isotope clearance can also be applied to determine the endogeneous creatinine clearance in otherwise less suitable patients. A reliable result is obtained even if the renal function is restricted, but the accuracy of the method may be reduced in nephrotic syndrome cases. (author) 24 refs

  1. Removal - An alternative to clearance

    International Nuclear Information System (INIS)

    Feinhals, J.; Kelch, A.; Kunze, V.

    2007-01-01

    This presentation shows the differences between the application of clearance and removal, both being procedures for materials leaving radiation protection areas permanently. The differentiation will be done on the basis of the German legislation but may be also applicable for other national legislation. For clearance in Germany two basic requirements must be given, i.e. that the materials are activated or contaminated and that they result from the licensed use or can be assigned to the scope of the license. Clearance needs not to be applied to objects in Germany which are to be removed only temporarily from controlled areas with the purpose of repair or reuse in other controlled areas. In these cases only the requirements of contamination control apply. In the case of removal it must either be proved by measurements that the relevant materials are neither activated nor contaminated or that the materials result from areas where activation or contamination is impossible due to the operational history considering operational procedures and events. If the material is considered neither activated nor contaminated there is no need for a clearance procedure. Therefore, these materials can be removed from radiation protection areas and the removal is in the responsibility of the licensee. Nevertheless, the removal procedure and the measuring techniques to be applied for the different types of materials need an agreement from the competent authority. In Germany a maximum value of 10% of the clearance values has been established in different licenses as a criterion for the application of removal. As approximately 2/3 of the total mass of a nuclear power plant is not expected to be contaminated or activated there is a need for such a procedure of removal for this non contaminated material without any regulatory control especially in the case of decommissioning. A remarkable example is NPP Stade where in the last three years more than 8600 Mg were disposed of by removal and

  2. 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...

  3. 31 CFR 205.20 - What is a clearance pattern?

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false What is a clearance pattern? 205.20... Agreement § 205.20 What is a clearance pattern? States use clearance patterns to project when funds are paid... patterns meet the following standards: (a) A clearance pattern must be auditable. (b) A clearance pattern...

  4. 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 ...

  5. 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.

  6. 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

  7. 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.)

  8. 78 FR 26786 - 510(k) Device Modifications: Deciding When To Submit a 510(k) for a Change to an Existing Device...

    Science.gov (United States)

    2013-05-08

    ...) is through Building 1 where routine security check procedures will be performed. For parking and... time and space permits, onsite registration on the day of the meeting will be provided beginning at 8 a...? F. Other Policy Proposals FDA acknowledges that any one of the above options may be insufficient on...

  9. Continuous measurement of DTPA-clearance in extracorporeal detoxification circuits.

    Science.gov (United States)

    Falkenhagen, D; Ahrenholz, P; Roy, T; Esther, G; Kiencke, H; Klinkmann, H

    1981-01-01

    A new method for investigating clearances is described. DTPA labelled with technetium 99m (MW: 496 daltons) is used as an agent to be measured. Continuous determination of the DTPA-clearance is possible in extracorporeal detoxification circuits including dialyzers, hemofilters and hemoperfusion columns. As an example, DTPA-clearances are given for two different dialyzers. In comparison to clearance measurements of peak 7, DTPA-clearance was very similar to that obtained for peak 7.

  10. Continuous measurement of DTPA-clearance in extracorporeal detoxification circuits

    Energy Technology Data Exchange (ETDEWEB)

    Falkenhagen, D.; Ahrenholz, P.; Roy, T.; Esther, G.; Kiencke, H.; Klinkmann, H.

    1981-01-01

    A new method for investigating clearances is described. DTPA labelled with technetium 99m (MW: 496 daltons) is used as an agent to be measured. Continuous determination of the DTPA-clearance is possible in extracorporeal detoxification circuits including dialyzers, hemofilters and hemoperfusion columns. As an example, DTPA-clearances are given for two different dialyzers. In comparison to clearance measurements of peak 7, DTPA-clearance was very similar to that obtained for peak 7.

  11. Recent activities on clearance in IAEA and clearance automatic laser inspection system (CLALIS)

    International Nuclear Information System (INIS)

    Hattori, Takatoshi; Sasaki, Michiya

    2005-01-01

    Exemption levels for bulk amounts of materials have been described in RS-G-1.7 published as a safety guide in IAEA on August 2004. In Japan, the Nuclear Safety Commission adopted the RS-G-1.7 values as Japanese clearance levels after the careful review of dose assessment results. After completing revises of regulatory laws in relation to clearance level, solid wastes from decommissioning and operating nuclear power plants will be targets of clearance inspection. In CRIEPI, Clearance Automatic Laser Inspection System (CLALIS) has been developed, which can give high reliability and objectivity to the measurement data. The CLALIS is a new monitoring system coupling with 3D laser shape measurement, Monte-Carlo calculation and gamma measurement techniques, which can keep a high accuracy in the measurement data using an automatic correction technique for self-shielding effects of metal waste itself and is expected to apply as a practical use in actual clearance inspections. (author)

  12. 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)

  13. Bronchographic and radioisotopic studies of bronchial clearance

    International Nuclear Information System (INIS)

    Ducousso, R.; Girerd, E.; Nolibe, D.; Metivier, H.; Masse, R.

    1974-01-01

    Bronchograms were performed on monkeys and rats after insufflation of iodinated contrast powders. The clearance kinetics of the contrast media were followed radiographically and by radioisotopic whole body and excreta counting. Because of the product's solubility their elimination through the kidney is augmented with increasing deposition in the peripheral airways. Our attempts to slow down clearance by inducing experimental bronchitis or by previous inhalation of plutonium oxide were unsuccessful. Only insufflation of particles with wounding edges was followed by much longer retention than usual. As opposed to tantalum, the slight solubility of the product allows their elimination with time [fr

  14. 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

  15. Clearance of seborrhoeic keratoses with topical dobesilate

    Science.gov (United States)

    Cuevas, Pedro; Angulo, Javier; Salgüero, Irene; Giménez-Gallego, Guillermo

    2012-01-01

    A patient with two seborrhoeic keratoses in the face received a single daily application of dobesilate cream during 6 months. Dobesilate achieved complete clearance of the seborrhoeic keratosis lesions with good cosmoses, suggesting that this compound is a safe and efficient candidate in the treatment of seborrhoeic keratoses. PMID:22729328

  16. Mechanisms of viral clearance and persistence.

    Science.gov (United States)

    Borrow, P

    1997-01-01

    Using examples predominantly drawn from study of the lymphocytic choriomeningitis virus (LCMV) model system, this review describes the mechanisms involved in control of virus infections by the cell-mediated immune response, and some of the different strategies viruses have evolved to evade such immune clearance so that they can persist in their hosts. The important role played by the CD8+ cytotoxic lymphocyte (CTL) response in clearance of many systemic virus infections is discussed; and it is emphasized that although CD8+ CTL are classically thought of as lymphocytes which mediate lysis of virus-infected target cells, the principal mechanism by which CD8+ T cells effect clearance of persistent and many acute virus infections via production of antiviral cytokines such as tumour necrosis factor-alpha and interferon-gamma, not via destruction of virus-producing cells. To avoid immune-mediated clearance, viruses frequently use a combination of several different strategies. These can be grouped into mechanisms for avoiding recognition by the immune response (such as establishing latent infections, replicating in immune-privileged sites, down-regulating the expression of immune recognition signals on the surface of infected cells, or undergoing antigenic variation); and mechanisms for suppressing the immune response. The latter include generalized immune suppression mechanisms, and strategies for more precisely disabling the specific immune response such as inducing tolerance or exhaustion of virus-specific CTL. The value of understanding both immune clearance mechanisms and viral evasion strategies in the rational design of immune-based therapies to combat persistent virus infections is discussed.

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. The clearance of albumin microspheres from an intramuscular injection site

    International Nuclear Information System (INIS)

    Mills, S.N.; Davis, S.S.; Frier, M.; Hardy, J.G.; Wilson, C.G.

    1982-01-01

    Human serum albumin microspheres of three different diameters were radiolabelled with indium-111, and a suspension injected into rabbit thigh muscle. Clearance from the intramuscular site was monitored for 2 weeks using gamma scintigraphy. The clearance rates were compared with the injection site clearance of non-biodegradable polystyrene microspheres. (U.K.)

  2. 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.

  3. Pipeline dynamics subject to restraints with clearance

    International Nuclear Information System (INIS)

    Loula, A.F.D.; Guerreiro, J.N.C.

    1980-12-01

    The principle of virtual works at its incremental form, is utilized for the formulation of flat pipeline vibration problems, of elastic-plastic behavior, submitted to restraints with clearance (also with elastic-plastic behavior) and with viscous damping. The possibility of uniform movement of the support, that simulates the seismic action is also considered. The finite element method and an integration time algorithm, are utilized for the problem resolution. Some examples ilustrate the application of the development program. (Author) [pt

  4. UGT polymorphisms and lamotrigine clearance during pregnancy

    DEFF Research Database (Denmark)

    Petrenaite, Vaiva; Öhman, Inger; Ekström, Lena

    2018-01-01

    OBJECTIVE: To evaluate the impact of maternal UGT1A4 and UGT2B7 genetic polymorphisms and sex of foetus on gestation-induced changes in lamotrigine (LTG) clearance during pregnancy and post-partum (PP). METHODS: Single nucleotide polymorphisms UGT1A4 142T > G, L48V (*3), UGT1A4 70C > A, P24T (*2)...

  5. 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.)

  6. 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)

  7. 75 FR 4402 - Strengthening the Center for Devices and Radiological Health's 510(k) Review Process; Public...

    Science.gov (United States)

    2010-01-27

    ... of the program and, if necessary, to recommend administrative, regulatory, and/or statutory changes... different ``intended uses'' and explain your reasoning. b. What are the advantages and disadvantages of... the advantages and disadvantages of combining these concepts into one term? B. Issues Related to New...

  8. 76 FR 14028 - Center for Devices and Radiological Health 510(k) Implementation: Online Repository of Medical...

    Science.gov (United States)

    2011-03-15

    ...) Implementation: Online Repository of Medical Device Labeling, Including Photographs; Public Meeting AGENCY: Food... of an Online Repository of Medical Device Labeling and of Making Device Photographs Available in a... public comment on the following topics: FDA's plans to establish an online public repository of medical...

  9. 21 CFR 807.93 - Content and format of a 510(k) statement.

    Science.gov (United States)

    2010-04-01

    ... certify that, in my capacity as (the position held in company by person required to submit the premarket... notification submission, including any adverse safety and effectiveness information, but excluding all patient..., whose name will be published by FDA on the list of premarket notification submissions for which...

  10. Glial K(+) Clearance and Cell Swelling

    DEFF Research Database (Denmark)

    Macaulay, Nanna; Zeuthen, Thomas

    2012-01-01

    An important feature of neuronal signalling is the increased concentration of K(+) in the extracellular space. The K(+) concentration is restored to its original basal level primarily by uptake into nearby glial cells. The molecular mechanisms by which K(+) is transferred from the extracellular...... space into the glial cell are debated. Although spatial buffer currents may occur, their quantitative contribution to K(+) clearance is uncertain. The concept of spatial buffering of K(+) precludes intracellular K(+) accumulation and is therefore (i) difficult to reconcile with the K(+) accumulation...

  11. Study of blade clearance effects on centrifugal pumps

    Science.gov (United States)

    Hoshide, R. K.; Nielson, C. E.

    1972-01-01

    A program of analysis, design, fabrication, and testing has been conducted to develop and experimentally verify analytical models to predict the effects of impeller blade clearance on centrifugal pumps. The effect of tip clearance on pump efficiency, and the relationship between the head coefficient and torque loss with tip clearance was established. Analysis were performed to determine the cost variation in design, manufacture, and test that would occur between unshrouded and shrouded impellers. An impeller, representative of typical rocket engine impellers, was modified by removing its front shroud to permit variation of its blade clearances. It was tested in water with special instrumentation to provide measurements of blade surface pressures during operation. Pump performance data were obtained from tests at various impeller tip clearances. Blade pressure data were obtained at the nominal tip clearance. Comparisons of predicted and measured data are given.

  12. 76 FR 47917 - Lead; Clearance and Clearance Testing Requirements for the Renovation, Repair, and Painting Program

    Science.gov (United States)

    2011-08-05

    ... clearance is the only method to ensure that no lead hazards remain upon the completion of a renovation job... rule that established accreditation, training, certification, and recordkeeping requirements as well as... training program accreditation application process, standards for e-learning in accredited training...

  13. 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.

  14. Mine Clearance Industry: Background, Geography, Funding, Analysis and Future Projections

    Science.gov (United States)

    2007-12-01

    Ingegneria dei Sistemi SpA Corporate Multi-sensor, Radar Spain 136 Ingenieria de Sistemas y de Software SA Corporate Data Fusion Spain 137...resources. 15. NUMBER OF PAGES 369 14. SUBJECT TERMS: Mine clearance Industry, Mine Clearance Firm, Mine Clearance Company, De -mining Industry...Demining Industry, Demining Company, De -mining Company, Commercial Demining Firm, Commercial De -mining Firm, Commercial Demining Company, Commercial

  15. Surfactant secretion and clearance in the newborn

    International Nuclear Information System (INIS)

    Stevens, P.A.; Wright, J.R.; Clements, J.A.

    1989-01-01

    Pregnant rabbits (30 days) were injected intravenously with [3H]choline 8 h before delivery. The fetuses were delivered, and lung lavage and lamellar body phospholipids (PL) were analyzed. Some newborns also received radioactively labeled surfactant intratracheally on delivery and were permitted to breathe. With time, intratracheal label decreased in lavage and appeared in the lamellar body fraction, and intravenous label accumulated in both pools. Using a tracer analysis for non-steady state, we calculated surfactant secretion and clearance rates for the newborn period. Before birth, both rates rose slightly from 1.8 micrograms PL.g body wt-1.h-1 at 6 h before birth to 7.3 at birth. Immediately after birth, secretion rate rose to 37.7 micrograms PL.g body wt-1.h-1. Between 1.5 and 2 h after birth it fell to a minimum of 1.8 micrograms PL.g body wt-1.h-1 and then rose slowly to 6.0 at 12 h. After birth, clearance rate increased less than secretion rate (maximum 24.7 micrograms PL.g body wt-1.h-1 shortly after birth) then followed the same pattern but did not balance secretion rate in the 1st day

  16. 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.

  17. 77 FR 44641 - Critical Infrastructure Private Sector Clearance Program Request

    Science.gov (United States)

    2012-07-30

    ... SECURITY Critical Infrastructure Private Sector Clearance Program Request AGENCY: National Protection and... Infrastructure Private Sector Clearance Program (PSCP). DHS previously published this ICR in the Federal Register... utility; 2. Evaluate the accuracy of the agency's estimate of the burden of the proposed collection of...

  18. 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...

  19. 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...

  20. 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...

  1. Blood flow and clearance in tendons. Studies with dogs.

    Science.gov (United States)

    Hooper, G; Davies, R; Tothill, P

    1984-05-01

    Blood flow in intact tendons in dogs was measured using 57Co-labelled microspheres and compared with the simultaneous clearance of a diffusible radionuclide, 85Sr, by the same tendons. Clearance was significantly greater than flow in all tendons, indicating that diffusion from surrounding tissues may be important in the nutrition of normal tendons.

  2. 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.

  3. 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

  4. 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

  5. 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

  6. Radioaerosol delivery and clearance in patients with respiratory failure

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, M.P.; Tennenberg, S.D.; Baughman, R.P.

    1987-12-01

    A technique for radioaerosol delivery to patients requiring mechanical ventilation is described. Ventilation images and pulmonary radioaerosol clearance rates were successfully obtained in 35 patients regardless of ventilator type or level of positive end-expiratory pressure (PEEP). Those patients with noncardiogenic pulmonary edema (NPE) had significantly increased clearance rates relative to those patients in whom NPE was not present.

  7. 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 ...

  8. 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

  9. [Determination of clearance for urea-controlled hemodialysis].

    Science.gov (United States)

    Ahrenholz, P; Holtz, M; Falkenhagen, D; Klinkmann, H

    1988-07-01

    Through a simple variant of the urea model the qualitative influence of the dialyzer-clearance on the individual dialysis guidance is elucidated. Realization of the respective Kdtd/V-value require an exact knowledge of the in-vivo-urea-clearance of all available dialyzer types and their manipulation with the aid of blood flow. The theoretical connections are explained and possible parameters affecting the in-vivo-clearance are discussed. The results concerning the dependence of urea-clearance on the blood flow are presented in an urea-guided dialysis patient pool for all in the GDR customary in the trade or temporary available dialyzers. It is shown, that in MLW-dialyzers an influence on the urea-clearance about the blood flow is small because of their relatively thick-walled membrane. Therefore, the development of dialysis membranes with superior diffusible permeability is necessary.

  10. 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

  11. 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

  12. 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.

  13. Numerical simulation of tip clearance impact on a pumpjet propulsor

    Directory of Open Access Journals (Sweden)

    Lin Lu

    2016-05-01

    Full Text Available Numerical simulation based on the Reynolds Averaged Navier–Stokes (RANS Computational Fluid Dynamics (CFD method had been carried out with the commercial code ANSYS CFX. The structured grid and SST k–ω turbulence model had been adopted. The impact of non-condensable gas (NCG on cavitation performance had been introduced into the Schnerr and Sauer cavitation model. The numerical investigation of cavitating flow of marine propeller E779A was carried out with different advance ratios and cavitation numbers to verify the numerical simulation method. Tip clearance effects on the performance of pumpjet propulsor had been investigated. Results showed that the structure and characteristics of the tip leakage vortex and the efficiency of the propulsor dropped more sharply with the increase of the tip clearance size. Furthermore, the numerical simulation of tip clearance cavitation of pumpjet propulsor had been presented with different rotational speed and tip clearance size. The mechanism of tip clearance cavitation causing a further loss of the efficiency had been studied. The influence of rotational speed and tip clearance size on tip clearance cavitation had been investigated.

  14. 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

  15. 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

  16. Mine-field clearance by nuclear weapons

    Energy Technology Data Exchange (ETDEWEB)

    Deeds, F.E.; Fleming, F.W.; Stump, R.K.

    1960-08-16

    The objective of the project was to investigate the behavior of pressure-activated antitank mines under air-blast loading from a nuclear detonation. Of particular interest were the reliability of current methods for predicting probability of land-mine actuation from nuclear detonations, the effect of burial depth on mine actuation, and the effect of sympathetic actuation in extending the range of mine clearance. In addition, a study was initiated to determine if special methods were needed for prediction of mine actuation at particular ranges of transition in the pressure-wave shape. Fifteen mine types, both United States and foreign, were employed. Test results indicated: (1) the procedures for predicting mine actuation under nuclear detonations were reasonably accurate; (2) in the live mine fields, sympathetic actuation occurred among mines; (3) the response of the Universal Indicator Mines (UIM) increased with burial depths to a maximum value between 6 and 9 in.; and (4) the reliability of the actuation curves can be improved by laboratory testing of adequate sampling mines.

  17. Automobile wheel clearance estimation using magnetism

    Science.gov (United States)

    Le Goff, A.; Lacoume, J.-L.; Blanpain, R.; Dauvé, S.; Serviere, C.

    2012-01-01

    With development and miniaturization of magnetic sensors for several years, it is now possible to imagine new applications using magnetic measures for monitoring and diagnostics. In this article this new way of research and development is presented with a concrete example concerning monitoring of wheels in an automobile. Our approach consists in using the low magnetic field created by the metallic elements of the wheel in order to localize them with low-cost high-sensitivity miniature magnetic sensors. The measures are made via a sensor network set up on a vehicle around the wheel. Then we use a physical model of the wheel in order to interpret the signals we get from the sensors. This method shows the interest of the magnetic measurement for monitoring in automobile. In this paper we present the magnetic signal created by a wheel, the mechanical model of the wheel and we present how we use them for an application: the real-time estimation of the distance between wheels and chassis (wheel clearance).

  18. 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

  19. Antibody-Mediated Clearance of Alphavirus Infection from Neurons

    Science.gov (United States)

    Levine, Beth; Hardwick, J. Marie; Trapp, Bruce D.; Crawford, Thomas O.; Bollinger, Robert C.; Griffin, Diane E.

    1991-11-01

    Humoral immunity is important for protection against viral infection and neutralization of extracellular virus, but clearance of virus from infected tissues is thought to be mediated solely by cellular immunity. However, in a SCID mouse model of persistent alphavirus encephalomyelitis, adoptive transfer of hyperimmune serum resulted in clearance of infectious virus and viral RNA from the nervous system, whereas adoptive transfer of sensitized T lymphocytes had no effect on viral replication. Three monoclonal antibodies to two different epitopes on the E2 envelope glycoprotein mediated viral clearance. Treatment of alphavirus-infected primary cultured rat neurons with these monoclonal antibodies to E2 resulted in decreased viral protein synthesis, followed by gradual termination of mature infectious virion production. Thus, antibody can mediate clearance of alphavirus infection from neurons by restricting viral gene expression.

  20. IFNL4 affects clearance of hepatitis C virus

    Science.gov (United States)

    Scientists have discovered a new human interferon gene, Interferon Lambda 4 (IFNL4), that affects clearance of the hepatitis C virus. They also identified an inherited genetic variant within IFNL4 that predicts how people respond to treatment for hepatit

  1. 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)

  2. Holistic approach to flutter clearance using classical methods

    CSIR Research Space (South Africa)

    Van Zyl, Lourens H

    2006-09-01

    Full Text Available Flutter clearance is usually regarded as a two step process: flutter analysis (including ground vibration testing, aerodynamic analysis and equation of motion solution), and flutter flight testing. The problem with this approach...

  3. 49 CFR 229.71 - Clearance above top of rail.

    Science.gov (United States)

    2010-10-01

    ....71 Clearance above top of rail. No part or appliance of a locomotive except the wheels, flexible nonmetallic sand pipe extension tips, and trip cock arms may be less than 21/2 inches above the top of rail. ...

  4. High Temperature Evaluation of an Active Clearance Control System Concept

    Science.gov (United States)

    Taylor, Shawn C.; Steinetz, Bruce M.; Oswald, Jay J.

    2006-01-01

    A mechanically actuated blade tip clearance control concept was evaluated in a nonrotating test rig to quantify secondary seal leakage at elevated temperatures. These tests were conducted to further investigate the feasibility of actively controlling the clearance between the rotor blade tips and the surrounding shroud seal in the high pressure turbine (HPT) section of a turbine engine. The test environment simulates the state of the back side of the HPT shroud seal with pressure differentials as high as 120 psig and temperatures up to 1000 F. As expected, static secondary seal leakage decreased with increasing temperature. At 1000 F, the test rig's calculated effective clearance (at 120 psig test pressure) was 0.0003 in., well within the industry specified effective clearance goal.

  5. 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...

  6. 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

  7. DOD Personnel Clearances: Preliminary Observations about Timeliness and Quality

    National Research Council Canada - National Science Library

    2008-01-01

    ...) personnel security clearance program. These findings are based on an ongoing engagement that we have been conducting since February 2008 under the Comptroller General's authority to conduct evaluations on his own initiative...

  8. Radioaerosol clearance to monitor effects of ozone on lung permeability

    International Nuclear Information System (INIS)

    Webb, D.A.; Utell, M.J.; Bauer, M.A.; Banko, T.M.; Waldman, D.L.; Morrow, P.E.; Hyde, R.W.

    1985-01-01

    The Tc-99m DTPA aerosol clearance procedure was used to investigate the effects of low level ozone inhalation on lung permeability. Total and regional lung clearance was determined by scintillation camera imaging of 15 adult subjects presenting no history of lung disease using a radioaerosol with an aerodynamic diameter 0.5 μm(σg=1.50). Pulmonary function measurements and the radioaerosol procedure were conducted in each patient on at least two separate occasions. FVC, FEVl and airway resistance was measured pre and post monitored breathing of room air (30 min) and a subsequent aerosol clearance procedure was conducted as a baseline study; the same procedures were repeated after three or more days with 0.5 ppm ozone substituted for room air. The major observations from the clearance studies and the pulmonary function tests include: 1) no significant changes were detected between the baseline and ozone pulmonary function tests, 2) ROI analyses of the 30 min clearance data show no significant changes in the average Tc-99m DTPA clearance between the baseline room air (t1/2=85+-30 min) and ozone (t1/2=83+-24min) inhalation studies, and, 3) despite consistent average clearance rates, 7/15 subjects showed large changes in clearance (Δ=24-72 min) and functional mapping showed major shifts in distribution in 5/15 subjects after ozone inhalation. The apparent high sensitivity, yet somewhat disparate observations, support the need of further investigation of factors influencing radioaerosol for the study of lung epithelial permeability

  9. 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...

  10. 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)

  11. Bronchoscintigraphy and pulmonary clearance of 99mTc-albumin colloid in study of mucociliary clearance

    International Nuclear Information System (INIS)

    Mortensen, Jann

    1998-01-01

    A radioaerosol based method for measuring MC was introduced. It included an inhalation protocol that resulted in a predominant deposition of radioaerosol in the central bronchi and two simple procedures of evaluation: 1) a visual semi-quantitative bronchoscintigraphic analysis, and 2) a quantitative analysis of the retention of the radioactivity at different points after the inhalation. The results showed that bronchoscintigraphy was a simple technique that may be used to visualize a stimulation of mucociliary transport in the central airways of individuals that do not suffer from too much mucus hypersecretion. Comparison of the MC between individuals, however, should preferably be performed by the method of quantitative analysis of the radioactivity disappearance. A change of MC was found to be one of the first detectable effects on lung function of tobacco smoking. It could be effectively detected by measurement of radioaerosol clearance both by bronchoscintigraphy and simple quantification of the MC. The MC may be either acutely enhanced, reduced or not changed by smoking. Long-term smoking impairs MC. The enhancement of MC by β 2 -agonists was very limited in most patients with CF. In the hope of increasing mucus transport in patients with CF, these are treated with various chest physiotherapy techniques. The radioaerosol based method of measurement of MC could assess mucus clearance by chest physiotherapy and cough. (au)

  12. 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.

  13. 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.

  14. Salicylate clearance, the resultant of protein binding and metabolism.

    Science.gov (United States)

    Furst, D E; Tozer, T N; Melmon, K L

    1979-09-01

    Steady-state plasma salicylate concentrations and protein binding were examined in 9 normal subjects to determine relationships among daily dose, total and unbound salicylate concentrations, and total and unbound clearances. Aspirin doses ranging from 0.66 to 4.0 mg/kg/hr were given to steady state. Free and total salicylate concentrations were measured with spectrophotometric, fluorimetric, and equilibrium dialysis techniques. Although unbound clearance decreased over the therapeutic range, total clearance was unchanged. The former is a consequence of saturable metabolism; the latter, of saturable plasma protein binding as well as saturable metabolism. The fraction unbound increased linearly with unbound concentration. Clearance determined at 1.8 mg/kg/hr was used to predict levels obtained at higher aspirin doses. Analysis of residuals was used to ascertain the accuracy of the prediction. The coefficient of variation from prediction among subjects was found to be +/- 14%. It is concluded that, in normal subjects, salicylate clearance changes relatively little over the therapeutic range because the increasing fraction unbound compensates for decreasing clearance of unbound drug.

  15. Urinary and metabolic clearances of arginine vasopressin in normal subjects

    International Nuclear Information System (INIS)

    Moses, A.M.; Steciak, E.

    1986-01-01

    Synthetic arginine vasopressin (AVP) was infused into 11 hydrated normal subjects at five different infusion rates ranging from 10 to 350 μU kg -1 min -1 . Each infusion rate was continued for 1 h, and urinary determinations were made on the 30- to 60-min specimens during which time there was no further rise in plasma AVP. Urinary AVP concentrations (μU/ml) and excretion rates (μU/min) increased linearly with increasing infusion rates, and the concentration of AVP in urine increased 120 times more rapid than plasma. Urinary and metabolic clearances of AVP also increased linearly with the maximum urinary clearance being 60.6% of the creatinine clearance. The total metabolic clearance of AVP (including urinary clearance) was 17.8 times that of the urinary clearance of AVP alone. These data clarify the relationships between plasma and urinary AVP in normal hydrated subjects during AVP infusion under steady-state conditions and emphasize the potential advantage of measuring urinary AVP as a monitor of endogenous AVP secretion. AVP was measured by radioimmunoassay

  16. Alcohol consumption decreases lactate clearance in acutely injured patients☆

    Science.gov (United States)

    Dezman, Zachary D.W.; Comer, Angela C.; Narayan, Mayur; Scalea, Thomas M.; Hirshon, Jon Mark; Smith, Gordon S.

    2017-01-01

    Introduction Alcohol, a common risk factor for injury, has direct toxic effects on the liver. The use of lactate clearance has been well described as an indicator of the adequacy of resuscitation in injured patients. We investigated whether acutely injured patients with positive blood alcohol content (+BAC) had less lactate clearance than sober patients. Methods We conducted a retrospective cohort study of acutely injured patients treated at an urban Level 1 trauma centre between January 2010 and December 2012. Blood alcohol and venous lactate levels were measured on all patients at the time of arrival. Study subjects were patients transported directly from the scene of injury, who had an elevated lactate concentration on arrival (≥3.0 mmol/L) and at least one subsequent lactate measurement within 24 h after admission. Lactate clearance ([Lactate1 − Lactate2]/Lactate1) was calculated for all patients. Chi-squared tests were used to compare values from sober and intoxicated subjects. Lactate clearance was plotted against alcohol levels and stratified by age and Injury Severity Score (ISS). Results Serial lactate concentration measurements were obtained in 3910 patients; 1674 of them had +BAC. Patients with +BAC were younger (mean age: 36.6 [SD 14.7] vs 41.0 [SD 19.9] years [p = 0.0001]), were more often male (83.4% vs 75.9% [p = 0.0001]), had more minor injuries (ISS 400 (23.5 [SD 6.5]). Lactate clearance decreased with increasing BAC irrespective of age and ISS. Conclusions In a large group of acutely injured patients, a dose-dependent decrease in lactate clearance was seen in those with elevated BAC. This relationship will cause a falsely elevated lactate reading or prolong lactate clearance and should be taken into account when evaluating patients with +BAC. PMID:27025567

  17. Alcohol consumption decreases lactate clearance in acutely injured patients.

    Science.gov (United States)

    Dezman, Zachary D W; Comer, Angela C; Narayan, Mayur; Scalea, Thomas M; Hirshon, Jon Mark; Smith, Gordon S

    2016-09-01

    Alcohol, a common risk factor for injury, has direct toxic effects on the liver. The use of lactate clearance has been well described as an indicator of the adequacy of resuscitation in injured patients. We investigated whether acutely injured patients with positive blood alcohol content (+BAC) had less lactate clearance than sober patients. We conducted a retrospective cohort study of acutely injured patients treated at an urban Level 1 trauma centre between January 2010 and December 2012. Blood alcohol and venous lactate levels were measured on all patients at the time of arrival. Study subjects were patients transported directly from the scene of injury, who had an elevated lactate concentration on arrival (≥3.0mmol/L) and at least one subsequent lactate measurement within 24h after admission. Lactate clearance ([Lactate1-Lactate2]/Lactate1) was calculated for all patients. Chi-squared tests were used to compare values from sober and intoxicated subjects. Lactate clearance was plotted against alcohol levels and stratified by age and Injury Severity Score (ISS). Serial lactate concentration measurements were obtained in 3910 patients; 1674 of them had +BAC. Patients with +BAC were younger (mean age: 36.6 [SD 14.7] vs 41.0 [SD 19.9] years [p=0.0001]), were more often male (83.4% vs 75.9% [p=0.0001]), had more minor injuries (ISS400 (23.5 [SD 6.5]). Lactate clearance decreased with increasing BAC irrespective of age and ISS. In a large group of acutely injured patients, a dose-dependent decrease in lactate clearance was seen in those with elevated BAC. This relationship will cause a falsely elevated lactate reading or prolong lactate clearance and should be taken into account when evaluating patients with +BAC. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Pulmonary function and clearance after prolonged sulfuric acid aerosol exposure

    Energy Technology Data Exchange (ETDEWEB)

    Ives, P.J. (ABB Environmental, Chapel Hill, NC (United States)); Gerrity, T.R.; DeWitt, P.; Folinsbee, L.J. (Environmental Protection Agency, Chapel Hill, NC (United States))

    1991-03-15

    The authors studied pulmonary function and clearance responses after a 4 H exposure to 75-100 {mu}g/m{sup 3} sulfuric acid aerosol (SAA). Healthy subjects, who exercised for 30 min/H at ventilation of about 25 L/min, were exposed once to clean air and once to SAA. Oral hygiene and acidic juice gargle were used to minimize oral ammonia. Lung function tests, including spirometry, plethysmography, and partial flow-volume (PEFV) curves were performed before and after exposure. Clearance of 99m-Technetium labeled iron oxide was assessed after each exposure. The first moment of fractional tracheobronchial retention (M1TBR), after correcting for 24 H retention and normalizing to time zero, was used as an index of clearance. There were no significant changes in lung volumes, airways resistance, or maximum expiratory flows after SAA exposure. Flow at 40% of total lung capacity on PEFV curves decreased 17% (NS) after SAA exposure. Tracheobronchial clearance was accelerated after a single exposure to SAA; M1TBR decreased from 73 {plus minus} 5 min (air) to 69 {plus minus} 5 min (SAA). These results suggest that acute prolonged exposure to low levels of SAA has minimal effects on lung mechanics in healthy subjects but does produce a modest acceleration of particle clearance.

  19. 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)

  20. The clinicalsignificance of chromium-51-EDTA-clearance

    International Nuclear Information System (INIS)

    Anger, G.; Senf, L.; Schmidt, U.; Macheleidt, S.

    1976-01-01

    In routine diagnostics the glomerular filtration rate was in most cases determined by endogenic creatinine clearance. Possibilities of errors in this method are unreliable accumulation of urine, influencibility of the creatinine values by the muscular mass and various exogenic factors. The chromium-51-EDTA-clearance is to be regarded as a more exact method. After single intravenous injection of about 150 μCi Cr-51-EDTA (single-shot-method) the impulse rates in the serum are measured after 60, 100, 140 and 180 min in the bore-hole-crystal. Up to now the number of patients examined is about 300, additionally 6 persons who underwent binephrectomy. Elaboration of a computer programme for the calculation of the clearance values. The best approach is achieved by non-linear regression. There exists a reciprocal connection between serum creatinine and Cr-51-EDTA-clearance. Values lower than 90 ml/min must be regarded as pathological. The Cr-51-EDTA-clearance is particularly valuable in the so-called creatinine-blind region, in which it gives a more reliable information about the beginning reduction of the glomerular filtration rate, as calculation of the correlation and repeated examinations show. The method can be recommended for the clinical routine diagnostics. (author)

  1. Renal clearance and degradation of glutathione-coated copper nanoparticles.

    Science.gov (United States)

    Yang, Shengyang; Sun, Shasha; Zhou, Chen; Hao, Guiyang; Liu, Jinbin; Ramezani, Saleh; Yu, Mengxiao; Sun, Xiankai; Zheng, Jie

    2015-03-18

    Degradation of inorganic nanoparticles (NPs) into small molecular complexes is often observed in the physiological environment; however, how this process influences renal clearance of inorganic NPs is largely unknown. By systematically comparing renal clearance of degradable luminescent glutathione coated copper NPs (GS-CuNPs) and their dissociated products, Cu(II)-glutathione disulfide (GSSG) complexes (Cu(II)-GSSG), we found that GS-CuNPs were eliminated through the urinary system surprisingly faster and accumulated in the liver much less than their smaller dissociation counterparts. With assistance of radiochemistry and positron emission tomography (PET) imaging, we found that the observed "nano size" effect in enhancing renal clearance is attributed to the fact that GS-CuNPs are more resistant to serum protein adsorption than Cu(II)-GSSG. In addition, since dissociation of GS-CuNPs follows zero-order chemical kinetics, their renal clearance and biodistribution also depend on initial injection doses and their dissociation processes. Quantitative understanding of size effect and other factors involved in renal clearance and biodistribution of degradable inorganic NPs will lay down a foundation for further development of renal-clearable inorganic NPs with minimized nanotoxicity.

  2. Using the Golden Triangle to optimize clearance and oral absorption.

    Science.gov (United States)

    Johnson, Ted W; Dress, Klaus R; Edwards, Martin

    2009-10-01

    The Golden Triangle is a visualization tool developed from in vitro permeability, in vitro clearance and computational data designed to aid medicinal chemists in achieving metabolically stable, permeable and potent drug candidates. Classifying compounds as permeable and stable and plotting molecular weight (MW) versus octanol:buffer (pH 7.4) distribution coefficients (logD) or estimated octanol:buffer (pH 7.4) distribution coefficients (elogD) reveals useful trends. Analysis of at least two orthogonal trends, such as permeability and clearance, can be extremely effective in balancing and optimizing multiple properties. In addition, molecular weight and logD impact potency-efficiency calculations, allowing potency, clearance and permeability to be optimized simultaneously.

  3. 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)

  4. 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)

  5. 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.

  6. 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.

  7. Clearance (free release) of slightly radioactive material in ARC Seibersdorf

    International Nuclear Information System (INIS)

    Lexa, D.

    2003-01-01

    A new radiation protection law designed to implement the recommendations of the 29/96/EURATOM directive has recently been adopted in Austria. Austrian Research Centers GmbH - ARC, Seibersdorf, is in the process of adapting its clearance operations accordingly. The conditions to be fulfilled prior to clearance derive from the 10 Sv/a additional dose concept. Activity concentration limits for each radionuclide result. In order to assure compliance with the rather restrictive values sophisticated free release measurements are called for. International experience has shown that acceptable results in terms of quality, throughput, and price, are practically only achievable by using a purpose built automated measurement unit, working on the principle of total counting. Calibration and measurement protocol play a key role in obtaining reliable results. The issue of homogeneity plays a central role in the clearance of objects exceeding regulatory mass (surface) limits. Experience with installation and operation of a free release measurement unit in ARC Seibersdorf are discussed. (authors)

  8. ITER waste management: The recycling and clearance option

    International Nuclear Information System (INIS)

    Rocco, P.; Zucchetti, M.

    1996-01-01

    To minimize the amount of radioactive waste requiring permanent disposal may strongly influence the environmental acceptability of fusion power. The waste management strategy applied here to the activated waste of ITER achieves this goal by maximizing recycling (reuse of the material) and clearance (declassification to non active waste). Limits of the surface dose rates of the waste after an interim storage of 50 years define various recycling procedures. The possibility of clearance is assessed from limits of the specific activity of the waste. These limits depend on the relative hazard of the radionuclides contained in the waste. It turns out that only a small part of ITER materials have such a radioactivity as to prevent its recycling or clearance (namely, first wall and front blanket). Most of the blanket and all the vessel may be recycled by remote handling. All the other components can be cleared or 'hands-on' recycled. 12 refs., 3 tabs

  9. 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)

  10. 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.

  11. 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

  12. In vitro investigations of citrate clearance with different dialysis filters.

    Science.gov (United States)

    Hartmann, Jens; Strobl, Karin; Fichtinger, Ute; Schildböck, Claudia; Falkenhagen, Dieter

    2012-05-01

    In extracorporeal blood purification, citrate anticoagulation offers several substantial advantages over conventional heparin anticoagulation. However, there is still a lack of information on citrate kinetics, especially on the citrate clearance of conventional hemodialyzers. The aim of this study was to investigate the citrate clearance for different hemodialysis filters as a basis for the development of an intelligent citrate-calcium infusion algorithm. For our experiments, the Fresenius 4008H dialysis machine and the dialysis filters FX 60, F6 HPS, F8 HPS (Fresenius Medical Care, Bad Homburg, Germany), Polyflux 140H and 14L (Gambro Holding, Stockholm, Sweden), Xenium 130 (Baxter AG, Vienna, Austria) and APS-650 (ASAHI Kasei Kuraray Medical, Chiyoda-ku, Japan) were used. Clearance calculations were performed based on plasma/blood flow rate and the citrate concentrations at filter inlet and outlet. All experiments were carried out in vitro with fresh frozen plasma (FFP) or whole blood. The results prove that citrate clearance is significantly higher with high-flux filters than with low-flux filters. Higher dialysate flow rates cause a more effective removal of citrate. The citrate clearance for low-flux and high-flux filters was 71 ± 7 and 86 ± 1% of the urea clearance, respectively. Citrate can efficiently be removed with standard hemodialysis. However, depending on the infused amounts as well as on the patient - especially in patients with impaired liver function - the use of a high-flux dialysis filter and a high dialysate flow rate should be considered to minimize the risk of citrate accumulation.

  13. 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.

  14. 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.

  15. 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)

  16. 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

  17. Antipyrine clearance during experimental and occupational exposure to toluene

    DEFF Research Database (Denmark)

    Døssing, M; Bælum, Jesper; Lundqvist, G R

    1983-01-01

    Exposure to toluene vapour enhances hepatic microsomal enzyme function in animals as assessed by the metabolism of the test drug antipyrine. Thirty six printing trade workers with long term occupational exposure to a mixture of organic solvents and 39 matched controls were randomly allocated...... clearance 12 printing trade workers with 17 years (median) of occupational exposure to toluene vapour at concentrations of about 100 ppm were investigated before and four weeks after cessation of exposure. No difference in antipyrine clearance was found either within the groups or between the groups at any...

  18. 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....

  19. Mucociliary Clearance Time in Patients with and without Rhinitis ...

    African Journals Online (AJOL)

    While rhinitis is not a life-threatening condition, complications may occur and the condition can significantly impair quality of life. In order to measure the mucociliary clearance time in patients with and without rhinitis a study was conducted in the ENT, H&N, and orthopedic departments at KNH. Methods: 130 cases between ...

  20. 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 fall in the sitting position, and fell significantly to 26 +/- 5 ml/min (p less than 0.025) in walking subjects. Absolute proximal tubular reabsorption rate of fluid correspondingly rose from 83 +/- 16 to 92 +/- 15 ml/min (p less than 0.005) and sodium clearance fell from 1.52 +/- 0.81 to 1.00 +/- 0...

  1. 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...

  2. [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.

  3. 75 FR 52798 - State-07, Cryptographic Clearance Records

    Science.gov (United States)

    2010-08-27

    ... Information Programs and Services, A/GIS/ IPS, Department of State, SA-2, 515 22nd Street, NW., Washington, DC... Department of State and Agency for International Development who have applied for cryptographic clearances as... that apply to all of its Privacy Act systems of records. These notices appear in the form of a...

  4. Effect of lindane on the clearance rate of Daphnia magna

    NARCIS (Netherlands)

    Hartgers, E.M.; Heugens, E.W.; Deneer, J.W.

    1999-01-01

    The impact of the insecticide lindane (%-hexachlorocyclohexane) on the clearance rate (CR) of Daphnia magna was investigated using artificial beads. CR (24-h EC50: 65 7g Lm1) was found to be a more sensitive endpoint than acute lethality for D. magna (48-h LC50: 516 7g Lm1). The onset of the effect

  5. 77 FR 22831 - Agency Information Collection Activities: Emergency Clearance Request

    Science.gov (United States)

    2012-04-17

    ... requiring clearance by the Office of Management and Budget (OMB) in compliance with Public Law 104-13, the... Operational Effectiveness (RIN 0960-AH35), Regulation 3729F--20 CFR 422.905, 422.906--0960-NEW Background When members of the public demonstrate disruptive, violent, or threatening actions or behavior toward SSA...

  6. Noncoding RNAs in protein clearance pathways: implications in ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 96; Issue 1. Noncoding RNAs in protein clearance pathways: implications in ... A class of small ncRNAs and miRNAs has gained much importance because of its involvement in human diseases such as cancer. Involvement of long ncRNAs have also been acknowledged in ...

  7. Spinal clearance guideline for out-of hospital providers

    Directory of Open Access Journals (Sweden)

    M. McCaul*

    2013-12-01

    Conclusion: An out-of hospital spinal clearance guideline was developed with evaluation and implementation strategies for the out-of hospital context. The author would like to acknowledge the South African Cochrane Centre and Dr Tamara Kredo for their support.

  8. Urea and Creatinine Clearances in the Three Trimesters of Pregnancy

    African Journals Online (AJOL)

    Abstract. The aim of this study was to determine the creatinine and urea clearances, as indices of glomerular filtration rate (GFR) during the three trimesters of pregnancy. A total of 108 healthy subjects between the ages of 18 and 37years were divided into non-pregnant women (28+5years, n=30), 1st trimester of pregnancy ...

  9. 76 FR 17978 - Agency Information Collection Activities: Emergency Clearance Request

    Science.gov (United States)

    2011-03-31

    ... requiring clearance by the Office of Management and Budget (OMB) in compliance with Public Law 104-13, the... Management and Budget, Attn: Desk Officer for SSA, Fax: 202-395-6974, E-mail address: [email protected] earnings for those years from their earnings records, ultimately reducing their Social Security benefits...

  10. 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.

  11. Mucociliary and cough clearance as a biomarker for therapeutic development

    DEFF Research Database (Denmark)

    Bennett, William D; Daviskas, Evangelia; Hasani, Amir

    2010-01-01

    A workshop/symposium on “Mucociliary and Cough Clearance (MCC/CC) as a Biomarker for Therapeutic Development” was held on October 21–22, 2008, in Research Triangle Park, NC, to discuss the methods for measurement of MCC/CC and how they may be optimized for assessing new therapies designed...

  12. 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.

  13. 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.

  14. 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.

  15. 46 CFR 61.20-23 - Tailshaft clearance; bearing weardown.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Tailshaft clearance; bearing weardown. 61.20-23 Section...; bearing weardown. (a) Water lubricated bearings, other than rubber, must be rebushed as follows: (1) Where the propelling machinery is located amidship, the after stern tube bearing must be rebushed when it is...

  16. Influence of clearance model on numerical simulation of centrifugal pump

    Science.gov (United States)

    Wang, Z.; Gao, B.; Yang, L.; Du, W. Q.

    2016-05-01

    Computing models are always simplified to save the computing resources and time. Particularly, the clearance that between impeller and pump casing is always ignored. But the completer model is, the more precise result of numerical simulation is in theory. This paper study the influence of clearance model on numerical simulation of centrifugal pump. We present such influence via comparing performance, flow characteristic and pressure pulsation of two cases that the one of two cases is the model pump with clearance and the other is not. And the results show that the head decreases and power increases so that efficiency decreases after computing with front and back cavities. Then no-leakage model would improve absolute velocity magnitude in order to reach the rated flow rate. Finally, more disturbance induced by front cavity flow and wear-ring flow would change the pressure pulsation of impeller and volute. The performance of clearance flow is important for the whole pump in performance, flow characteristic, pressure pulsation and other respects.

  17. Measuring Clearance Mechanics Based on Dynamic Leg Length

    Science.gov (United States)

    Khamis, Sam; Danino, Barry; Hayek, Shlomo; Carmeli, Eli

    2018-01-01

    The aim of this study was to quantify clearance mechanics during gait. Seventeen children diagnosed with hemiplegic cerebral palsy underwent a three-dimensional gait analysis evaluation. Dynamic leg lengths were measured from the hip joint center to the heel, to the ankle joint center and to the forefoot throughout the gait cycle. Significant…

  18. 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.

  19. Association of serum cytokines with oral HPV clearance.

    Science.gov (United States)

    Lam, Jennifer O; Bream, Jay H; Sugar, Elizabeth A; Coles, Christian L; Weber, Kathleen M; Burk, Robert D; Wiley, Dorothy J; Cranston, Ross D; Reddy, Susheel; Margolick, Joseph B; Strickler, Howard D; Wentz, Alicia; Jacobson, Lisa; Guo, Yingshi; Xiao, Weihong; Gillison, Maura L; D'Souza, Gypsyamber

    2016-07-01

    Initial studies suggest higher serum levels of some pro-inflammatory cytokines may be associated with decreased cervical human papillomavirus (HPV) clearance. However, the relationship of cytokines with oral HPV clearance has not been explored. From 2010 to 2014, oral rinse and serum samples were collected semi-annually from 1601 adults. Oral rinse samples were tested for HPV DNA using PCR. Based on oral HPV results, 931 serum samples were selected for cytokine evaluation to include a roughly equal number of prevalent (n=307), incident (n=313), and no oral HPV infections (n=311). Electrochemiluminescence multiplex assays were used to determine the concentrations of IL-6, IL-8, TNF-α, IFN-γ, IL-1β, IL-2, IL-4, IL-10, IL-12 and IL-13. The relationship between serum cytokine concentrations (categorized into quartiles) and oral HPV clearance was evaluated with Wei-Lin-Weissfeld regression models, adjusting for HPV infection type (prevalent vs. incident), age, HIV status, and CD4 T cell count. Higher TNF-α concentration was associated with decreased clearance in men (highest vs. lowest quartile, adjusted hazard ratio [aHR]=0.52, 95% CI=0.34-0.79) and women (aHR=0.76, 95% confidence interval [CI]=0.55-1.04), with stronger associations in men than women (p-interaction=0.049). Higher IL-2 concentration was associated with reduced clearance in men (aHR=0.69, 95% CI=0.50-0.95), but not women (p-interaction=0.058). Results were similar within CD4 T cell strata (CD4⩾500 or CD4oral HPV infection. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. 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)

  1. 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)

  2. 77 FR 28625 - Comment Request for Information Collection for the Agricultural and Food Processing Clearance...

    Science.gov (United States)

    2012-05-15

    ... DEPARTMENT OF LABOR Employment and Training Administration Comment Request for Information Collection for the Agricultural and Food Processing Clearance Order, ETA Form 790, Extension With Revisions, and the Agricultural and Food Processing Clearance Memorandum, ETA Form 795, Extension Without...

  3. A comparison of analytic procedures for measurement of fractional dextran clearances

    NARCIS (Netherlands)

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

    1998-01-01

    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

  4. Wartime Distribution Operations: Roles of Focused Logistics, Velocity Management, Strategic Distribution Policy and Air Clearance Policy

    National Research Council Canada - National Science Library

    Gardner, Mark

    2004-01-01

    ...) and service policies on materiel consolidation and air clearance authority. The paper argues that developing common DoD and services policies for materiel consolidation and air clearance will result in a more effective joint distribution system...

  5. 77 FR 15139 - Agency Information Collection Activities: Comment Request; Generic Survey Clearance for the...

    Science.gov (United States)

    2012-03-14

    ... workforce. NSF funds grants, contracts, and cooperative agreements to colleges, universities, and other..., 2005, 2008, and 2011 OMB Terms of Clearances, NSF requests separate stand-alone clearance (and...

  6. 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

    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...

  7. 10 CFR 110.121 - Security clearances and access to classified information.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Security clearances and access to classified information... clearances and access to classified information. (a) No person without a security clearance will have access to classified information. (b) Only the Commission will act upon an application for access to...

  8. 76 FR 27741 - 60-Day Notice of Proposed Information Collection: Technology Security/Clearance Plans, Screening...

    Science.gov (United States)

    2011-05-12

    ...: Technology Security/Clearance Plans, Screening Records, and Non-Disclosure Agreements ACTION: Notice of...: Technology Security/ Clearance Plans, Screening Records, and Non-Disclosure Agreements Pursuant to 22 CFR 126... by the consignee or end-user. Section 126.18 also provides that the technology security/clearance...

  9. 76 FR 45645 - 10-Day Notice of Proposed Information Collection: Technology Security/Clearance Plans, Screening...

    Science.gov (United States)

    2011-07-29

    ...: Technology Security/Clearance Plans, Screening Records, and Non-Disclosure Agreements ACTION: Notice of... Information Collection: Technology Security/ Clearance Plans, Screening Records, and Non-Disclosure Agreements... consignee or end-user. Section 126.18 also provides that the technology security/clearance plan, screening...

  10. Railway Tunnel Clearance Inspection Method Based on 3D Point Cloud from Mobile Laser Scanning

    Science.gov (United States)

    Zhou, Yuhui; Wang, Shaohua; Mei, Xi; Yin, Wangling; Lin, Chunfeng; Mao, Qingzhou

    2017-01-01

    Railway tunnel clearance is directly related to the safe operation of trains and upgrading of freight capacity. As more and more railway are put into operation and the operation is continuously becoming faster, the railway tunnel clearance inspection should be more precise and efficient. In view of the problems existing in traditional tunnel clearance inspection methods, such as low density, slow speed and a lot of manual operations, this paper proposes a tunnel clearance inspection approach based on 3D point clouds obtained by a mobile laser scanning system (MLS). First, a dynamic coordinate system for railway tunnel clearance inspection has been proposed. A rail line extraction algorithm based on 3D linear fitting is implemented from the segmented point cloud to establish a dynamic clearance coordinate system. Second, a method to seamlessly connect all rail segments based on the railway clearance restrictions, and a seamless rail alignment is formed sequentially from the middle tunnel section to both ends. Finally, based on the rail alignment and the track clearance coordinate system, different types of clearance frames are introduced for intrusion operation with the tunnel section to realize the tunnel clearance inspection. By taking the Shuanghekou Tunnel of the Chengdu–Kunming Railway as an example, when the clearance inspection is carried out by the method mentioned herein, its precision can reach 0.03 m, and difference types of clearances can be effectively calculated. This method has a wide application prospects. PMID:28880232

  11. 76 FR 59379 - Proposed Information Collection; Comment Request; Generic Clearance for Research in Development...

    Science.gov (United States)

    2011-09-26

    ... Proposed Information Collection; Comment Request; Generic Clearance for Research in Development of... submit a Generic Information Collection Request (Generic ICR): ``Generic Clearance for Research in Development of Disclosure Forms'' to OMB for review and clearance under the Paperwork Reduction Act of 1995...

  12. 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

    The kidneys are thought to play an important role in the clearance of recombinant human growth hormone (rhGH), but the relative importance is not clear. Obtaining knowledge of clearance pathway is an important prerequisite for the development of new long acting growth hormone analogues targeted...... that renal clearance plays a pivotal role in the elimination of rhGH in rats....

  13. 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.

  14. Railway Tunnel Clearance Inspection Method Based on 3D Point Cloud from Mobile Laser Scanning.

    Science.gov (United States)

    Zhou, Yuhui; Wang, Shaohua; Mei, Xi; Yin, Wangling; Lin, Chunfeng; Hu, Qingwu; Mao, Qingzhou

    2017-09-07

    Railway tunnel clearance is directly related to the safe operation of trains and upgrading of freight capacity. As more and more railway are put into operation and the operation is continuously becoming faster, the railway tunnel clearance inspection should be more precise and efficient. In view of the problems existing in traditional tunnel clearance inspection methods, such as low density, slow speed and a lot of manual operations, this paper proposes a tunnel clearance inspection approach based on 3D point clouds obtained by a mobile laser scanning system (MLS). First, a dynamic coordinate system for railway tunnel clearance inspection has been proposed. A rail line extraction algorithm based on 3D linear fitting is implemented from the segmented point cloud to establish a dynamic clearance coordinate system. Second, a method to seamlessly connect all rail segments based on the railway clearance restrictions, and a seamless rail alignment is formed sequentially from the middle tunnel section to both ends. Finally, based on the rail alignment and the track clearance coordinate system, different types of clearance frames are introduced for intrusion operation with the tunnel section to realize the tunnel clearance inspection. By taking the Shuanghekou Tunnel of the Chengdu-Kunming Railway as an example, when the clearance inspection is carried out by the method mentioned herein, its precision can reach 0.03 m, and difference types of clearances can be effectively calculated. This method has a wide application prospects.

  15. Preparation of iodine-125-labeled iothalamate for renal clearance measurements

    International Nuclear Information System (INIS)

    Rao, S.A.; Herold, T.J.; Dewanjee, M.K.

    1983-01-01

    Iothalamate, a derivative of benzoic acid, is used as a contrast medium for renal function studies, particularly for measurement of glomerular filtration rate. Its chemical composition and clearance properties are similar to those of diatrizoate. The structural differences between these groups of iodinated benzoic acid derivatives are dependent on the groups attached at the 3- and 5-positions of 2,4,6-tri-iodobenzoic acid. The renal clearance of sodium iothalamate in humans closely approximates that of inulin, and it is used as a replacement for inulin in determining glomerular filtration rate. /sup 125/I-labeled iothalamate sodium can be prepared by the exchange-labeling method at pH 4.0. Iothalamate must first be isolated from the contrast medium preparation and purified before radioiodination. After radioiodination, the product is purified by means of precipitation and is then converted to the sodium salt

  16. Diesel Engine Valve Clearance Detection Using Acoustic Emission

    Directory of Open Access Journals (Sweden)

    Fathi Elamin

    2010-01-01

    Full Text Available This paper investigated, using experimental method, the suitability of acoustic emission (AE technique for the condition monitoring of diesel engine valve faults. The clearance fault was adjusted experimentally in an exhaust valve and successfully detected and diagnosed in a Ford FSD 425 four-cylinder, four-stroke, in-line OHV, direct injection diesel engine. The effect of faulty exhaust valve clearance on engine performance was monitored and the difference between the healthy and faulty engine was observed from the recorded AE signals. The measured results from this technique show that using only time domain and frequency domain analysis of acoustic emission signals can give a superior measure of engine condition. This concludes that acoustic emission is a powerful and reliable method of detection and diagnosis of the faults in diesel engines and this is considered to be a unique approach to condition monitoring of valve performance.

  17. Robotic Range Clearance Competition (R2C2)

    Science.gov (United States)

    2011-10-01

    distribution unlimited. 88ABW-2012-5009, 19 September 2012. • Command & control needs: Wifi Aircards, name tags, clocks, lightning detectors...all the events they competed in. To accommodate the demonstration, 3 previously felled trees were “ planted ” for each of the vegetation clearance...a concrete monument has been planted at each localization point to allow competitors to calibrate their GPS readings to the values measured by the

  18. 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

  19. Prognostic value of lactate clearance in severe community acquired pneumonia

    OpenAIRE

    Mohamed, Kamel Abd Elaziz; Ahmed, Dief Abd Elgalil

    2014-01-01

    Introduction: Severe community acquired pneumonia (SCAP) occurs in approximately 18–36% of all CAP and the mortality rate could be as high as 67% in patients with SCAP. Several studies have described a correlation between baseline lactate concentration and mortality of ICU patients. Aim of the work: To follow lactate clearance after admission for 24 h which could be an indicator of outcome in severe community acquired pneumonia. Patients and methods: Forty-six consecutively admitted adu...

  20. 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.

  1. Effect of oral activated charcoal on tobramycin clearance.

    Science.gov (United States)

    Davis, R L; Koup, J R; Roon, R A; Opheim, K E; Smith, A N

    1988-01-01

    To evaluate the effect of activated charcoal on aminoglycoside pharmacokinetics, six healthy volunteers received tobramycin intravenously with and without multiple oral doses of activated charcoal. Activated charcoal did not have a statistically significant effect on any pharmacokinetic parameter. We conclude that activated charcoal does not enhance tobramycin clearance in subjects with normal renal function when concentrations in serum are within the therapeutic range. PMID:3364947

  2. 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)

  3. Lung clearance of aerosolized 99mTc erythromycin lactobionate in rabbits

    International Nuclear Information System (INIS)

    Durak, Hatice; Ertay, Tuerkan; Sayit, Elvan; Aktogu, Serir; Kut, Oezlem; Gueven, Huelya; Guere, Ataman

    1996-01-01

    In order to assess the lung clearance of aerosolized 99m Tc Erythromycin Lactobionate (EL), 99m Tc EL was administered to 9 New Zealand rabbits by inhalation. 5 rabbits inhaled cigarette smoke before 99m Tc EL. Clearance half times were 3.0 ± 0.9 hours in normals, 5.5 ± 1.0 hours after smoke exposure. Clearance was not affected after destroying the surfactant layer. Slower clearance after smoke exposure may be due to the inhibition of mucociliary clearance. 99m Tc EL can be considered as an alternative radioaerosol for ventilation imaging

  4. 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.

  5. Active Piezoelectric Structures for Tip Clearance Management Assessed

    Science.gov (United States)

    1995-01-01

    Managing blade tip clearance in turbomachinery stages is critical to developing advanced subsonic propulsion systems. Active casing structures with embedded piezoelectric actuators appear to be a promising solution. They can control static and dynamic tip clearance, compensate for uneven deflections, and accomplish electromechanical coupling at the material level. In addition, they have a compact design. To assess the feasibility of this concept and assist the development of these novel structures, the NASA Lewis Research Center developed in-house computational capabilities for composite structures with piezoelectric actuators and sensors, and subsequently used them to simulate candidate active casing structures. The simulations indicated the potential of active casings to modify the blade tip clearance enough to improve stage efficiency. They also provided valuable design information, such as preliminary actuator configurations (number and location) and the corresponding voltage patterns required to compensate for uneven casing deformations. An active ovalization of a casing with four discrete piezoceramic actuators attached on the outer surface is shown. The center figure shows the predicted radial displacements along the hoop direction that are induced when electrostatic voltage is applied at the piezoceramic actuators. This work, which has demonstrated the capabilities of in-house computational models to analyze and design active casing structures, is expected to contribute toward the development of advanced subsonic engines.

  6. Nonpharmacologic airway clearance techniques in hospitalized patients: a systematic review.

    Science.gov (United States)

    Andrews, Jeff; Sathe, Nila A; Krishnaswami, Shanthi; McPheeters, Melissa L

    2013-12-01

    Nonpharmacologic airway clearance techniques are used to reduce the sequelae of obstructive secretions. We systematically reviewed comparative studies of nonpharmacologic interventions that health professionals can employ to achieve mucus clearance in hospitalized or postoperative patients without cystic fibrosis, over the age of 12 months. We searched MEDLINE and other databases from 1990 to 2012 to identify relevant literature. Two reviewers independently assessed each study against predetermined inclusion/exclusion criteria. Two reviewers also independently extracted data regarding subject and intervention characteristics and outcomes, and assigned overall quality ratings. The 32 studies meeting the review criteria included 24 randomized controlled trials, 7 crossover randomized controlled trials, and one prospective cohort study. Studies were typically small and together included a total of 2,453 subjects (mean 76/study). Studies generally examined chest physical therapy/physiotherapy modalities in postoperative or critically ill subjects or those with COPD. Interventions, comparators, and populations varied considerably across studies, hampering our ability to draw firm conclusions. Interventions, including conventional chest physical therapy/physiotherapy, intrapulmonary percussive ventilation, and positive expiratory pressure, typically provided small benefits in pulmonary function, gas exchange, oxygenation, and need for/duration of ventilation, among other outcomes, but differences between groups were generally small and not significant. Harms of the techniques were not consistently reported, though airway clearance techniques were generally considered safe in studies that did comment on adverse effects. Further research with clearly characterized populations and interventions is needed to understand the potential benefits and harms of these techniques.

  7. 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.

  8. Smoking produced mucus and clearance of particulates in the lung

    Energy Technology Data Exchange (ETDEWEB)

    Sterling, T.D. [Simon Fraser Univ., Burnaby, British Columbia (Canada); Poland, T.M. [Theodor D. Sterling and Associates Ltd., Vancouver, British Columbia (Canada)

    1992-12-31

    Some studies of miners have shown a lesser relative lung-cancer risk for smokers than for nonsmokers. For example, experiments by Cross and associates with dogs have shown an apparent protective effect of cigarette smoke against radon-daughter and dust exposure. One reason for these changes may be the thickened mucus layer in the tracheobronchial region of smokers. Physiological changes in the lung due to smoking may decrease the effects of radioactive particles in cancers in the bronchial region by apparently promoting faster clearance, in that region, of radioactive particles and by decreasing the radiation dose through reduced penetration to the sensitive basal epithelial cells. Because of the short half-life of radon daughters, even if there is possible tobacco-related delay of particle clearance from the alveolar region it cannot affect radon clearance. Therefore, the possible mitigating effect of tobacco on radon-produced cancer appears to be limited to the tracheobronchial region. It would be of value to a number of occupations if the same changes in the lungs due to smoking could be produced in exposed workers in the absence of cigarette-smoking. Beta-carotene and vitamin A, which affect maintenance and secretion of the mucosal lining, appear to thicken mucus, thereby providing protection against radon-induced lung cancers that is similar to smoking-related changes in the lung.

  9. Reducing prescribing errors through creatinine clearance alert redesign.

    Science.gov (United States)

    Melton, Brittany L; Zillich, Alan J; Russell, Scott A; Weiner, Michael; McManus, M Sue; Spina, Jeffrey R; Russ, Alissa L

    2015-10-01

    Literature has shown that computerized creatinine clearance alerts reduce errors during prescribing, and applying human factors principles may further reduce errors. Our objective was to apply human factors principles to creatinine clearance alert design and assess whether the redesigned alerts increase usability and reduce prescribing errors compared with the original alerts. Twenty Veterans Affairs (VA) outpatient providers (14 physicians, 2 nurse practitioners, and 4 clinical pharmacists) completed 2 usability sessions in a counterbalanced study to evaluate original and redesigned alerts. Each session consisted of fictional patient scenarios with 3 medications that warranted prescribing changes because of renal impairment, each associated with creatinine clearance alerts. Quantitative and qualitative data were collected to assess alert usability and the occurrence of prescribing errors. There were 43% fewer prescribing errors with the redesigned alerts compared with the original alerts (P = .001). Compared with the original alerts, redesigned alerts significantly reduced prescribing errors for allopurinol and ibuprofen (85% vs 40% and 65% vs 25%, P = .012 and P = .008, respectively), but not for spironolactone (85% vs 65%). Nine providers (45%) voiced confusion about why the alert was appearing when they encountered the original alert design. When laboratory links were presented on the redesigned alert, laboratory information was accessed 3.5 times more frequently. Although prescribing errors were high with both alert designs, the redesigned alerts significantly improved prescribing outcomes. This investigation provides some of the first evidence on how alerts may be designed to support safer prescribing for patients with renal impairment. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. 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.

  11. Capreomycin kinetics in renal impairment and clearance by hemodialysis.

    Science.gov (United States)

    Lehmann, C R; Garrett, L E; Winn, R E; Springberg, P D; Vicks, S; Porter, D K; Pierson, W P; Wolny, J D; Brier, G L; Black, H R

    1988-11-01

    The single-dose kinetics of capreomycin are described for 12 renal patients and seven healthy control subjects. Creatinine clearances (CrCl) ranged from zero to 121 ml/min. After single-dose intravenous infusions, mean +/- SD capreomycin clearance values (L/kg/h x 10(-2)) were 0.558 +/- 0.160 for the dialysis group (n = 4, CrCl = 1.4 +/- 1.9), 1.77 +/- 0.45 for the moderate renal group (n = 3, CrCl = 25 +/- 5), 2.82 +/- 1.52 for the mild renal group (n = 4, CrCl = 46 +/- 5), and 5.73 +/- 1.54 for the normal renal group (n = 7, CrCl = 109 +/- 11); p less than 0.01, using analysis of variance. The correlation between capreomycin clearance and CrCl was r = 0.90. Hemodialysis cleared clinically significant amounts of capreomycin. These data imply that capreomycin maintenance doses need to be reduced for renal patients.

  12. Smoking produced mucus and clearance of particulates in the lung

    International Nuclear Information System (INIS)

    Sterling, T.D.; Poland, T.M.

    1992-01-01

    Some studies of miners have shown a lesser relative lung-cancer risk for smokers than for nonsmokers. For example, experiments by Cross and associates with dogs have shown an apparent protective effect of cigarette smoke against radon-daughter and dust exposure. One reason for these changes may be the thickened mucus layer in the tracheobronchial region of smokers. Physiological changes in the lung due to smoking may decrease the effects of radioactive particles in cancers in the bronchial region by apparently promoting faster clearance, in that region, of radioactive particles and by decreasing the radiation dose through reduced penetration to the sensitive basal epithelial cells. Because of the short half-life of radon daughters, even if there is possible tobacco-related delay of particle clearance from the alveolar region it cannot affect radon clearance. Therefore, the possible mitigating effect of tobacco on radon-produced cancer appears to be limited to the tracheobronchial region. It would be of value to a number of occupations if the same changes in the lungs due to smoking could be produced in exposed workers in the absence of cigarette-smoking. Beta-carotene and vitamin A, which affect maintenance and secretion of the mucosal lining, appear to thicken mucus, thereby providing protection against radon-induced lung cancers that is similar to smoking-related changes in the lung

  13. Numerical investigation of tip clearance effects on the performance of ducted propeller

    Directory of Open Access Journals (Sweden)

    Ding Yongle

    2015-09-01

    Full Text Available Tip clearance loss is a limitation of the improvement of turbomachine performance. Previous studies show the Tip clearance loss is generated by the leakage flow through the tip clearance, and is roughly linearly proportional to the gap size. This study investigates the tip clearance effects on the performance of ducted propeller. The investigation was carried out by solving the Navier-Stokes equations with the commercial Computational Fluid Dynamic (CFD code CFX14.5. These simulations were carried out to determine the underlying mechanisms of the tip clearance effects. The calculations were performed at three different chosen advance ratios. Simulation results showed that the tip loss slope was not linearly at high advance due to the reversed pressure at the leading edge. Three type of vortical structures were observed in the tip clearance at different clearance size.

  14. Land clearance and hydrological change in the Sahel: SW Niger

    Science.gov (United States)

    Leblanc, Marc J.; Favreau, Guillaume; Massuel, Sylvain; Tweed, Sarah O.; Loireau, Maud; Cappelaere, Bernard

    2008-04-01

    In the West African semiarid belt of the Sahel, for the second half of the XXth century, lasting droughts (1970s-1980s) and one of the World's highest population growths have resulted in major land cover and hydrological changes that can be quantified using aerial photographs. This paper aims to provide one of the longest combined observations of land cover and hydrological changes for semiarid areas using a time series of normalised mosaics of aerial photographs dating back from 1950, field inquiries, and updated groundwater data. The 500 km 2 study area in southwest Niger was chosen (i) for its rural environment representative of the rain-fed agriculture belt of the Sahel and (ii) to encompass the main hydrological study sites investigated in this region over the past two decades (Hapex-Sahel and AMMA experiments, 1990-2000s). Results have significant implications for future freshwater availability and food security in the Sahel. Between 1950 and 1992, ˜ 80% of the study area has been cleared, firstly to open new areas for agriculture and secondly for firewood supply (59% of the plateaux, 42% of the valley bottoms, and 87% of the hillslopes). Intermediate aerial photograph surveys (1960, 1975) attest an accelerated loss in the woody savannah that could not be recovered on the short term. A strong, indirect impact of land clearance is observed on the water resources. Land clearance has resulted in a modification of the soil properties and infiltration capacity and has led to an increase in Hortonian runoff collected in numerous gullies and ponds. Between 1950 and 1992, aerial photographs show a ˜ 2.5 fold increase of the drainage density with the development of large drainage systems and new ponds. Groundwater data also indicate a continuous rise in the water table, mostly noticeable since the 1980s with a mean groundwater level rise of ˜ 4 m for the 1963-2005 period (+ 15% in aquifer reserves). The relatively short ˜ 30 year time-lag between the onset of land

  15. Beta2-microglobulin and phosphate clearances using a wearable artificial kidney: a pilot study.

    Science.gov (United States)

    Gura, Victor; Davenport, Andrew; Beizai, Masoud; Ezon, Carlos; Ronco, Claudio

    2009-07-01

    Additional small-solute clearances during standard thrice-weekly hemodialysis treatments have not improved patient survival. However, these treatments have limited middle-molecule clearances. Thus, newer therapies designed to increase middle-molecule clearances need to be developed and evaluated. Pilot clinical trial to measure beta(2)-microglobulin and phosphate clearances with a wearable hemodialysis device. 8 regular hemodialysis patients under the care of a university teaching hospital. Patients were fitted with a wearable hemodialysis device for 4 to 8 hours. All patients tolerated the treatment. Average amount of beta(2)-microglobulin removed was 99.8 +/- 63.1 mg, with mean clearance of 11.3 +/- 2.3 mL/min, and an average of 445.2 +/- 326 mg of phosphate was removed, with mean plasma phosphate clearance of 21.7 +/- 4.5 mL/min. These clearances compared favorably with mean urea and creatinine plasma clearances (21.8 +/- 1.6 and 20.0 +/- 0.8 mL/min, respectively). Proof-of-concept preliminary trial. Additional studies are warranted to confirm these positive preliminary data. This wearable artificial kidney potentially provides effective beta(2)-microglobulin and phosphate clearances and, by analogy, middle-molecule clearances.

  16. RGS21, A Regulator of Taste and Mucociliary Clearance?

    Science.gov (United States)

    Kimple, Adam J.; Garland, Alaina L.; Cohen, Staci P.; Setola, Vincent; Willard, Francis S.; Zielinski, Thomas; Lowery, Robert G.; Tarran, Robert; Siderovski, David P.

    2014-01-01

    Objectives/Hypothesis: Motile cilia of airway epithelial cells help to expel harmful inhaled material. Activation of bitterant-responsive G protein-coupled receptors (GPCRs) is believed to potentiate cilia beat frequency and mucociliary clearance. In this study, we investigated whether regulator of G protein signaling-21 (RGS21) has the potential to modulate signaling pathways connected to airway mucociliary clearance, given that RGS proteins modulate GPCR signaling by acting as GTPase-accelerating proteins (GAPs) for the Gα subunits of heterotrimeric G proteins. Study Design: This is a pilot investigation to determine if RGS21, a potential tastant specific RGS gene, is expressed in sinonasal mucosa, and to determine its specific Gα substrate using in vitro biochemical assays with purified proteins. Methods: Rgs21 expression in sinonasal mucosa was determined using quantitative, real-time PCR and a transgenic mouse expressing RFP from the Rgs21 promoter. Rgs21 was cloned, over-expressed, and purified using multistep protein chromatography. Biochemical and biophysical assays were used to determine if RGS21 could bind and accelerate the hydrolysis of GTP on heterotrimeric Gα subunits. Results: Rgs21 was expressed in sinonasal mucosa and lingual epithelium. Purified recombinant protein directly bound and accelerated GTP hydrolysis on Gα subunits. Conclusions: Rgs21 is expressed in sinonasal mucosa, is amenable to purification as a recombinant protein, and can bind to Gαi/o/q subunits. Furthermore, RGS21 can accelerate the hydrolysis rate of GTP on Gαi subunits. This provides evidence that RGS21 may be a negative regulator of bitterant responses. Future studies will be needed to determine the physiological role of this protein in mucociliary clearance. PMID:23908053

  17. SOIL QUALITY CHANGES FOLLOWING FOREST CLEARANCE IN BENGKULU, SUMATRA

    Directory of Open Access Journals (Sweden)

    I.P. HANDAYANI

    2004-01-01

    Full Text Available Intense destruction and degradation of tropical forests is recognized as one of the environmental threats and tragedies. These have increased the need to assess the effects of subsequent land-use following forest extraction on soil quality. Therefore, the objective of this study is to evaluate the impacts of land-use type on soil quality properties in Bengkulu Province, Sumatra. Soil samples were collected from adjacent sites including natural secondary forest, bare land, cultivated land and grassland. The results show that land-use following forest clearance lowered saturated hydraulic conductivity (85%, porosity (10.50%, soil water content at field capacity (34%,C organic (27%, N total (26%, inorganic N (37%, soil microbial biomass C (32%, mineralizable C (22%, and particulate organic matter (50%, but slightly increased water soluble organic C. Specific respiration activi ty rates increased about 14% in cultivated soils compared to natural forest soils, indicating greater C turnover per labile C pool in the form of soil microbial biomass, thus decreased biologically active soil organic matter. Forest conversion tends to reduce the C,ffg/Crer for all deforested sites. All of deforested areas relatively have infertile soil, with the worst case found in cultivated field. The C^g/Crd of cultivated field s was about 24% less than that of remnant fo rest (1.07. Grassland apparently mainta ins only slightly higher soil C levels than the bare land. On average, degradation index of so il following forest clearance was 35% with the highest deterioration occurred in the bare land (38%. Fallowing the fields by naturally growth of Imperata cylindrica for about 15 yr in abandoned land after 3-5 years of cultivation did not improve the soil quality. Moreover, forest clearance has an impact on soil quality as resulted in the loss of a physically protected organic matter and reduction in some labile C pools, thus declined biological activity at disturbed

  18. Dual clearance squeeze film damper for high load conditions

    Science.gov (United States)

    Fleming, D. P.

    1985-01-01

    Squeeze film dampers are widely used to control vibrations in aircraft turbine engines and other rotating machinery. However, if shaft unbalance rises appreciably above the design value (e.g., due to a turbine blade loss), a conventional squeeze film becomes overloaded, and is no longer effective in controlling vibration amplitudes and bearing forces. A damper concept characterized by two oil films is described. Under normal conditions, only one low-clearance film is active, allowing precise location of the shaft centerline. Under high unbalance conditions, both films are active, controlling shaft vibration in a near-optimum manner, and allowing continued operation until a safe shutdown can be made.

  19. 133Xe clearance as a diagnostic method in periodontology

    International Nuclear Information System (INIS)

    Schmidt, H.; Drauschke, M.; Vollmer, P.; Dumtzlaff, H.

    1988-01-01

    By means of tissue clearance no sex difference was stated in the regions of maxillary and mandibular front teeth in the gingiva of 35 males with generally good health and healthy periodontium and 41 females. A comparison between the age groups 17 to 20 years, 21 to 28 years and 30 to 44, resp., years did not result in a ascertained difference of the gingival circulation index under the same clinical conditions. But there is a significant difference between the circulation index of maxilla and mandible. (author)

  20. Mucociliary and cough clearance as a biomarker for therapeutic development

    DEFF Research Database (Denmark)

    Bennett, William D; Daviskas, Evangelia; Hasani, Amir

    2010-01-01

    or therapeutic evaluation presented details of their methodologies. Attendees participating in the workshop discussions included those interested in the physiology of MCC/CC, some of who use in vitro or animal methods for its study, pharmaceutical companies developing muco-active therapies, and many who were......A workshop/symposium on “Mucociliary and Cough Clearance (MCC/CC) as a Biomarker for Therapeutic Development” was held on October 21–22, 2008, in Research Triangle Park, NC, to discuss the methods for measurement of MCC/CC and how they may be optimized for assessing new therapies designed...

  1. Lung clearance of polydispersed colloidal 198Au particles

    International Nuclear Information System (INIS)

    D'Addabbo, A.; Fanfani, G.

    1975-01-01

    Lung clearance was studied on a group of subjects over 65 years old and on subjects aged between 30 and 40. A slowing down of material deposited in the bronchial tubes (polydispersed colloidal 198 Au particles) was observed in the senile subjects. This phenomenon is apparently related not only to a reduced activity of the vibratile ciliae, in connection with the frequent metaplasia of the bronchial cylindrical epithelium, but also to a quantitative and qualitative change in the mucopolysaccharides forming the mucus secretion [fr

  2. Lung clearance of inhaled cobalt oxide in man

    International Nuclear Information System (INIS)

    Pearman, I.; Foster, P.P.; Ramsden, D.; Bains, M.E.D.

    1989-01-01

    Winfrith AEE has contributed to the interspecies comparison of lung clearance co-ordinated by the European Late Effects Projects Group (EULEP). This study reported in the Journal of Aerosol Science March 1989, used a moderate amount of 57 Co material. It concentrated on inter-species comparisons for the first 200 days after inhalation. Winfrith conducted inhalation studies on four human volunteers. This paper reports a continuation of these studies for a further 500 days. Retention and excretion data for this extended period is compared to ICRP 30 models and to the earlier conclusion formed from the first 200 day experience. (author)

  3. Clearance, recycling and disposal of fusion activated material

    International Nuclear Information System (INIS)

    Zucchetti, M.; Forrest, R.; Forty, C.; Gulden, W.; Rocco, P.; Rosanvallon, S.

    2001-01-01

    The SEAFP-99 waste management studies include further explorations in the direction of activated materials management, adopting a more realistic approach in order to consolidate and refine the previous encouraging findings of SEAFP waste management studies performed till 1998. The main results were obtained in the following topics, impact of materials/components optimisation on waste management issues; integrated approach to recycling and clearance; analysis of the potential for fusion specific repositories and hazard-relevant nuclides/processes; materials detritiation. The overall conclusion is that the adoption of a more realistic approach for the analysis has been beneficial. The results further confirmed the potential for waste minimisation and hazard reduction

  4. Bacterial clearance after total splenectomy and splenic autotransplantation in rats

    Energy Technology Data Exchange (ETDEWEB)

    Marques, R.G. E-mail: rmarques@uerj.br; Petroianu, Andy; Oliveira, M.B.N. de; Bernardo-Filho, M.; Boasquevisque, E.M.; Portela, M.C

    2002-12-01

    Wistar rats submitted to isolated total splenectomy or total splenectomy combined with splenic autotransplantation were inoculated with {sup 99m}technetium-labeled Escherichia coli. Measurement of isotope uptake in the organs of the mononuclear phagocytic system showed a greater bacterial bloodstream clearance in rats with splenic autotransplantation. Although uptake of bacteria in the spleen was higher in the control group, the number of bacteria remaining in the bloodstream did not differ between groups. These results indicate that splenic autotransplantation preserves the phagocytic function of the spleen.

  5. Bacterial clearance after total splenectomy and splenic autotransplantation in rats

    International Nuclear Information System (INIS)

    Marques, R.G.; Petroianu, Andy; Oliveira, M.B.N. de; Bernardo-Filho, M.; Boasquevisque, E.M.; Portela, M.C.

    2002-01-01

    Wistar rats submitted to isolated total splenectomy or total splenectomy combined with splenic autotransplantation were inoculated with 99m technetium-labeled Escherichia coli. Measurement of isotope uptake in the organs of the mononuclear phagocytic system showed a greater bacterial bloodstream clearance in rats with splenic autotransplantation. Although uptake of bacteria in the spleen was higher in the control group, the number of bacteria remaining in the bloodstream did not differ between groups. These results indicate that splenic autotransplantation preserves the phagocytic function of the spleen

  6. Autophagic clearance of bacterial pathogens: molecular recognition of intracellular microorganisms.

    Science.gov (United States)

    Pareja, Maria Eugenia Mansilla; Colombo, Maria I

    2013-01-01

    Autophagy is involved in several physiological and pathological processes. One of the key roles of the autophagic pathway is to participate in the first line of defense against the invasion of pathogens, as part of the innate immune response. Targeting of intracellular bacteria by the autophagic machinery, either in the cytoplasm or within vacuolar compartments, helps to control bacterial proliferation in the host cell, controlling also the spreading of the infection. In this review we will describe the means used by diverse bacterial pathogens to survive intracellularly and how they are recognized by the autophagic molecular machinery, as well as the mechanisms used to avoid autophagic clearance.

  7. 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

  8. 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.

  9. 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...

  10. 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

  11. Clearance of HCV RNA following acute hepatitis A superinfection.

    Science.gov (United States)

    Cacopardo, B; Nunnari, G; Nigro, L

    2009-05-01

    A transient reduction of hepatitis C virus replication during the course of acute hepatitis A virus infection has already been reported in the literature. The present study reports the case study of a subject with chronic hepatitis due to hepatitis C virus who went on to develop an acute hepatitis A. From the early onset of acute disease, hepatitis C virus ribonucleic acid became undetectable. Following recovery from acute hepatitis, alanine amino-transferase levels became persistently normal and liver biopsy revealed a reduction in the Knodell histological activity index score. Hepatitis C virus ribonucleic acid clearance was maintained up to 4 years after the onset of acute hepatitis A. During the course of the acute disease, a sharp increase in interferon gamma levels was detected in serum and in the supernatant of both unstimulated and phytoemagglutinin/lipopolysaccharide-stimulated peripheral blood mononuclear cells. Interferon gamma levels were still high 3 months later. We hypothesize that acute hepatitis A virus superinfection during the course of chronic hepatitis C may lead to hepatitis C virus ribonucleic acid clearance through an immunological mechanism related to interferon gamma production.

  12. Biliary clearance of bromosulfophthalein in healthy and ketotic Holstein cows

    Directory of Open Access Journals (Sweden)

    Danijela Kirovski

    2013-09-01

    Full Text Available Ketosis is a metabolic disorder closely associated with liver lipidosis. Numerous tests have been developed to detect hepatic dysfunction in dairy cows. Bromosulfophthalein (BSP clearance is established as a sensitive index of hepatic function. The objective of this study was to examine the difference of biliary excretion of BSP between ketotic and healthy Holstein cows and to correlate this excretion with other indicators of liver dysfunction. Twenty puerperal Holstein cows divided in two groups (10 cows each were involved in the study. The first group included healthy and the second group ketotic cows. Blood samples were taken 10 days after parturition. Concentrations of total protein, albumin, total bilirubin, Ca, P, total lipids, urea and glucose were determined. Immediately after blood sampling, BSP test was performed. Blood samples were taken 5 and 45 minutes after injection, and the percentage of retained pigment in the sample obtained at minute 45 was calculated. Blood albumin and glucose concentrations were significantly higher in healthy then ketotic cows. Total bilirubin concentration was significantly higher in ketotic than healthy cows. BSP excretion was significantly higher in ketotic compared to healthy cows. There was a significant positive correlation between BSP values and total bilirubin concentrartions in both healthy and ketotic cows and a significant negative correlation between BSP values and glucose concentrartions in both healthy and ketotic cows. In conclusion, biliary clearance of BSP may be used as a reliable method for the detection of hepatic dysfunction associated with clinical symptoms of ketosis in dairy cows.

  13. Clearance of refractory bile duct stones with extracorporeal shockwave lithotripsy.

    Science.gov (United States)

    Ellis, R D; Jenkins, A P; Thompson, R P; Ede, R J

    2000-11-01

    Extracorporeal shockwave lithotripsy (ESWL) has been used since the mid-1980s to fragment bile duct stones which cannot be removed endoscopically. Early machines required general anaesthesia and immersion in a waterbath. To investigate the effectiveness of the third generation Storz Modulith SL20 lithotriptor in fragmenting bile duct stones that could not be cleared by mechanical lithotripsy. Eighty three patients with retained bile duct stones were treated. All patients received intravenous benzodiazepine sedation and pethidine analgesia. Stones were targeted by fluoroscopy following injection of contrast via a nasobiliary drain or T tube. Residual fragments were cleared at endoscopic retrograde cholangiopancreatography. Complete stone clearance was achieved in 69 (83%) patients and in 18 of 24 patients (75%) who required more than one ESWL treatment. Stone clearance was achieved in all nine patients (100%) with intrahepatic stones and also in nine patients (100%) referred following surgical exploration of the bile duct. Complications included six cases of cholangitis and one perinephric haematoma which resolved spontaneously. Using the Storz Modulith, 83% of refractory bile duct calculi were cleared with a low rate of complications. These results confirm that ESWL is an excellent alternative to surgery in those patients in whom endoscopic techniques have failed.

  14. Histamine Clearance Through Polyspecific Transporters in the Brain.

    Science.gov (United States)

    Yoshikawa, Takeo; Yanai, Kazuhiko

    2017-01-01

    Histamine plays an important role as a neurotransmitter in diverse brain functions, and clearance of histamine is essential to avoid excessive histaminergic neuronal activity. Histamine N-methyltransferase, which is an enzyme in the central nervous system that metabolizes histamine, is localized to the cytosol. This suggests that a histamine transport process is essential to inactivate histamine. Previous reports have shown the importance of astrocytes for histamine transport, although neuronal histamine transport could not be ruled out. High-affinity and selective histamine transporters have not yet been discovered, although it has been reported that the following three polyspecific transporters transport histamine: organic cation transporter (OCT) 2, OCT3, and plasma membrane monoamine transporter (PMAT). The K m values of human OCT2, OCT3, and PMAT are 0.54, 0.64, and 4.4 mM, respectively. The three transporters are expressed in the brain, and their regional distribution is different. Recent studies revealed the contribution of OCT3 and PMAT to histamine transport by primary human astrocytes. Several investigations using mice supported the importance of OCT3 for histamine clearance in the brain. However, further studies are required to elucidate the detailed mechanism of histamine transport in the brain.

  15. Semen amyloids participate in spermatozoa selection and clearance

    Science.gov (United States)

    Roan, Nadia R; Sandi-Monroy, Nathallie; Kohgadai, Nargis; Usmani, Shariq M; Hamil, Katherine G; Neidleman, Jason; Montano, Mauricio; Ständker, Ludger; Röcker, Annika; Cavrois, Marielle; Rosen, Jared; Marson, Kara; Smith, James F; Pilcher, Christopher D; Gagsteiger, Friedrich; Sakk, Olena; O’Rand, Michael; Lishko, Polina V; Kirchhoff, Frank

    2017-01-01

    Unlike other human biological fluids, semen contains multiple types of amyloid fibrils in the absence of disease. These fibrils enhance HIV infection by promoting viral fusion to cellular targets, but their natural function remained unknown. The similarities shared between HIV fusion to host cell and sperm fusion to oocyte led us to examine whether these fibrils promote fertilization. Surprisingly, the fibrils inhibited fertilization by immobilizing sperm. Interestingly, however, this immobilization facilitated uptake and clearance of sperm by macrophages, which are known to infiltrate the female reproductive tract (FRT) following semen exposure. In the presence of semen fibrils, damaged and apoptotic sperm were more rapidly phagocytosed than healthy ones, suggesting that deposition of semen fibrils in the lower FRT facilitates clearance of poor-quality sperm. Our findings suggest that amyloid fibrils in semen may play a role in reproduction by participating in sperm selection and facilitating the rapid removal of sperm antigens. DOI: http://dx.doi.org/10.7554/eLife.24888.001 PMID:28653619

  16. Reduction in slow intercompartmental clearance of urea during dialysis

    International Nuclear Information System (INIS)

    Bowsher, D.J.; Krejcie, T.C.; Avram, M.J.; Chow, M.J.; Del Greco, F.; Atkinson, A.J. Jr.

    1985-01-01

    The kinetics of urea and inulin were analyzed in five anesthetized dogs during sequential 2-hour periods before, during, and after hemodialysis. The distribution of both compounds after simultaneous intravenous injection was characterized by three-compartment models, and the total volumes of urea (0.66 +/- 0.05 L/kg) and inulin (0.19 +/- 0.01 L/kg) distribution were similar to expected values for total body water and extravascular space, respectively. Intercompartmental clearances calculated before dialysis were used to estimate blood flows to the fast and slow equilibrating compartments. In agreement with previous results, the sum of these flows was similar to cardiac output, averaging 101% of cardiac output measured before dialysis (range 72% to 135%). Dialysis was accompanied by reductions in the slow intercompartmental clearances of urea (81%) and inulin (47%), which reflected a 90% attenuation in blood flow supplying the slow equilibrating compartments. This was estimated to result in a 10% average reduction in the efficiency with which urea was removed by dialysis (range 2.0% to 16.4%). Mean arterial pressure fell by less than 5% during dialysis, but total peripheral resistance increased by 47% and cardiac output fell by 35%. In the postdialysis period, total peripheral resistance and cardiac output returned toward predialysis values, but blood flow to the slow equilibrating peripheral compartment was still reduced by 80%. These changes parallel activation of the renin-angiotensin system, but further studies are required to establish causality

  17. Robotic Mounted Detection System: robotics for route clearance

    Science.gov (United States)

    Hutchison, John; Klager, Gene; McCoy, Edward; Fite, David; Frederick, Brian

    2010-04-01

    Robotic Mounted Detection System (RMDS) is a government program to enable robotic control of a Husky route clearance vehicle with a mine detection sensor payload. The goal is for the operator to control the Husky and mine detection sensor from another vehicle. This program will provide the user with standard tele-operation control of the vehicle as well as semi-autonomous modes including cruise control, precision waypoint navigation with operator error correction and a visual mode allowing the operator to enter waypoints in the current video feed. The use of autonomy will be tailored to give the operator maximum control of the robotic vehicle's path while minimizing the effort required to maintain the desired route. Autonomous alterations of the path would conflict with the goal of route clearance, so waypoint navigation will allow the operator to supply offsets to counteract location errors. While following a waypoint path, the Husky will be capable of controlling its speed to maintain an operator specified distance from the control vehicle. Obstacle avoidance will be limited to protecting the mine detection sensor, leaving any decision to leave the path up to the operator. Video will be the primary navigational sensor feed to the operator, who will use an augmented steering wheel controller and computer display to control the Husky. A LADAR system will be used to detect obstacles that could damage the mine sensor and to maintain the optimal sensor orientation while the vehicle is moving. Practical issues and lessons learned during integration will be presented.

  18. Two-phase deep-lung clearance in man

    International Nuclear Information System (INIS)

    Bohning, D.E.; Cohn, S.H.; Lee, H.D.; Atkins, H.L.

    1980-01-01

    For toxicological as well as physiological considerations, it is important to determine whether the long-term clearance of particles from the lungs of man takes place in more than one temporal subphase. Although long-term retention can be characterized with a single exponential, the existence of two distinct components would significantly alter estimates of overall residence times and hence potential effects of inhaled particulates. Physiological interpretations of the mechanisms of long-term particle clearance depend on the identification and quantification of such temporal subphases. A highly sensitive whole-body counter was used to measure the long-term retention of inhaled particles in man. After inhalation of 85 Sr, lung retention was monitored in eight volunteers for periods ranging from 197 to 399 days. Their pulmonary-function values fell within normal limits, and they reported no symptoms of lung disease. Four of the individuals had never smoked, and four had not smoked for a minimum of 5 years. Single exponential representation half-times for the long-term retention were comparable between the two groups and were combined to give a mean half-time of 197 +- 32 days

  19. Effectiveness of small barriers as means to reduce clearance distances

    Energy Technology Data Exchange (ETDEWEB)

    Tchouvelev, Andrei V.; Cheng, Zhong [A.V.Tchouvelev and Associates, 6591 Spinnaker Circle, Mississauga, Ont. (Canada); Agranat, Vladimir M. [Hydrogenics Corp., 5985 McLaughlin Road, Mississauga, Ont. (Canada); Zhubrin, Serguei V. [Flowsolve Limited, 130 Arthur Road, London SW19 8AA (United Kingdom)

    2007-07-15

    Hydrogen clearance or safety distance can be defined as the minimum distance between a hydrogen leak source and surrounding equipment, property or personnel beyond which the risk to the said recipients associated with existing hydrogen hazards is deemed acceptable. The same principal is applied to determine clearances to ignition sources and air intakes only the criteria in this case are the risk of ignition or the risk of intaking a flammable mixture. The study of effects of small barriers as means to reduce clearance distances for compressed hydrogen releases is important for the development of installation codes and risk mitigation requirements. In this paper, computational fluid dynamics (CFD) modeling techniques were applied to the numerical simulation of the effects of a protective wall of 1 m by 1 m on reducing the size of hydrogen cloud. The protective wall was 1 m away from a 70 MPa (700 bar) 60 L tank, from which an incidental hydrogen release impinged horizontally onto the wall, causing a complicated 3D dispersion of hydrogen cloud. In-house CFD codes first accurately estimated the non-linear hydrogen mass release rate decreasing with time. Then the effects of the wall on the propagation speed of the hydrogen cloud moving behind the wall were investigated using the PHOENICS software package, provided with both the ideal gas law and the real gas law expressed by the Abel-Nobel equation of state (AN-EOS). The distributions of lower flammability limit (LFL) and 50% of LFL hydrogen clouds were described in detail based on the numerical results. It was found that the 50% of LFL hydrogen clouds (2% vol) could propagate behind the wall in less than 0.2 s after the onset of the release. The horizontal extents corresponding to 50% of LFL hydrogen cloud on the central vertical plane are 9.6 m at 5 s when they are predicted using the ideal gas law. When using the real gas law, the predicted extents decrease to 6.3 m at 5 s. The ideal gas law significantly

  20. In vitro-in vivo correlation for intrinsic clearance for drugs metabolized by human aldehyde oxidase.

    Science.gov (United States)

    Zientek, Michael; Jiang, Ying; Youdim, Kuresh; Obach, R Scott

    2010-08-01

    The ability to predict in vivo clearance from in vitro intrinsic clearance for compounds metabolized by aldehyde oxidase has not been demonstrated. To date, there is no established scaling method for predicting aldehyde oxidase-mediated clearance using in vitro or animal data. This challenge is exacerbated by the fact that rats and dogs, two of the laboratory animal species commonly used to develop in vitro-in vivo correlations of clearance, differ from humans with regard to expression of aldehyde oxidase. The objective of this investigation was to develop an in vitro-in vivo correlation of intrinsic clearance for aldehyde oxidase, using 11 drugs known to be metabolized by this enzyme. The set consisted of methotrexate, XK-469, (+/-)-4-(4-cyanoanilino)-5,6-dihydro-7-hydroxy-7H-cyclopenta[d]pyrimidine (RS-8359), zaleplon, 6-deoxypenciclovir, zoniporide, O(6)-benzylguanine, N-[(2'-dimethylamino)ethyl]acridine-4-carboxamide (DACA), carbazeran, PF-4217903, and PF-945863. These compounds were assayed using two in vitro systems (pooled human liver cytosol and liver S-9 fractions) to calculate scaled unbound intrinsic clearance, and they were then compared with calculated in vivo unbound intrinsic clearance. The investigation provided a relative scale that can be used for in vitro-in vivo correlation of aldehyde oxidase clearance and suggests limits as to when a potential new drug candidate that is metabolized by this enzyme will possess acceptable human clearance, or when structural modification is required to reduce aldehyde oxidase catalyzed metabolism.

  1. 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 cystic fibrosis. Duration of acid neutralization during 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.

  2. 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

    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...... similar in the two groups and decreased during exercise. Intracellular nonphosphorylated 2DG was present in tissues with high glucose clearances. In conclusions, 42 h of immobilization markedly impairs glucose clearance of resting red muscle fibers in vivo. Apparently, physical inactivity in particular...

  3. 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)

  4. 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

  5. Bronchoscintigraphy and pulmonary clearance of {sup 99{sup m}}Tc-albumin colloid in study of mucociliary clearance

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, Jann

    1998-12-31

    A radioaerosol based method for measuring MC was introduced. It included an inhalation protocol that resulted in a predominant deposition of radioaerosol in the central bronchi and two simple procedures of evaluation: 1) a visual semi-quantitative bronchoscintigraphic analysis, and 2) a quantitative analysis of the retention of the radioactivity at different points after the inhalation. The results showed that bronchoscintigraphy was a simple technique that may be used to visualize a stimulation of mucociliary transport in the central airways of individuals that do not suffer from too much mucus hypersecretion. Comparison of the MC between individuals, however, should preferably be performed by the method of quantitative analysis of the radioactivity disappearance. A change of MC was found to be one of the first detectable effects on lung function of tobacco smoking. It could be effectively detected by measurement of radioaerosol clearance both by bronchoscintigraphy and simple quantification of the MC. The MC may be either acutely enhanced, reduced or not changed by smoking. Long-term smoking impairs MC. The enhancement of MC by {beta}{sub 2}-agonists was very limited in most patients with CF. In the hope of increasing mucus transport in patients with CF, these are treated with various chest physiotherapy techniques. The radioaerosol based method of measurement of MC could assess mucus clearance by chest physiotherapy and cough. (au) 141 refs.

  6. Lactate Clearance Predicts Survival Among Patients in the Emergency Department with Severe Sepsis

    Directory of Open Access Journals (Sweden)

    Sundeep R. Bhat

    2015-12-01

    Full Text Available Introduction: Lactate clearance has been implicated as a predictor of mortality among emergency department (ED patients with severe sepsis or septic shock. We aimed to validate prior studies showing that lactate clearance during the ED stay is associated with decreased mortality. Methods: Retrospective dual-centered cross-sectional study using patients identified in the YaleNew Haven Hospital Emergency Medicine sepsis registry with severe sepsis or septic shock who had initial lactate levels measured in the ED and upon arrival (<24 hours to the hospital floor. Lactate clearance was calculated as percent of serum lactate change from ED to floor measurement. We compared mortality and hospital interventions between patients who cleared lactate and those who did not. Results: 207 patients (110 male; 63.17±17.9 years were included. Two reviewers extracted data with 95% agreement. One hundred thirty-six patients (65.7% had severe sepsis and 71 patients (34.3% had septic shock. There were 171 patients in the clearance group and 36 patients in the non-clearance group. The 28-day mortality rates were 15.2% in the lactate clearance group and 36.1% in the non-clearance group (p<0.01. Vasopressor support was initiated more often in the nonclearance group (61.1% than in the clearance group (36.8%, p<0.01 and mechanical ventilation was used in 66.7% of the non-clearance group and 36.3% of the clearance group (p=0.001. Conclusion: Patients who do not clear their lactate in the ED have significantly higher mortality than those with decreasing lactate levels. Our results are confirmatory of other literature supporting that lactate clearance may be used to stratify mortality-risk among patients with severe sepsis or septic shock.

  7. Factors effective on peritoneal phosphorus transport and clearance in peritoneal dialysis patients
.

    Science.gov (United States)

    Cebeci, Egemen; Gursu, Meltem; Uzun, Sami; Karadag, Serhat; Kazancioglu, Rumeyza; Ozturk, Savas

    2017-02-01

    Transport characteristics of phosphorus are different from other small solutes that are evaluated in routine peritoneal equilibration test (PET) in peritoneal dialysis (PD) patients. We aimed to evaluate peritoneal phosphorus clearance and permeability, and their relationship with peritoneal membrane transport type and creatinine clearance as well as factors affecting peritoneal phosphorus clearance. 70 adult patients on a PD program were included in our study. Phosphorus transport status was classified according to dialysate/plasma (D/P) phosphorus at the 4th hour of PET as slow transporter ( 0.67). We evaluated the relationship of peritoneal phosphorus clearance and transport type with PD regime, phosphorus level, and presence of residual renal function in addition to investigating factors that are effective on peritoneal phosphorus clearance. D/P phosphorus and peritoneal phosphorus clearance were positively correlated with D/P creatinine and peritoneal creatinine clearance, respectively. Automated PD and continuous ambulatory PD patients were similar regarding phosphorus and creatinine clearances and transport status based on D/P phosphorus. The major determinant of peritoneal phosphorus clearance was anuria status. Anuric patients had higher dialysate volume (11.6 ± 3.0 L vs. 8.4 ± 2.1 L, p peritoneal phosphorus clearance (61.7 ± 15.1 L/week/1.73 m2 vs. 48.4 ± 14.0 L/week/1.73 m2, p = 0.001). Hyperphosphatemia was present in 40% and 11% of anuric patients and those with residual renal function, respectively (p = 0.005). Peritoneal phosphorus transport characteristics are similar to that of creatinine. Although increased dialysis dose may increase peritoneal phosphorus clearance, it may be insufficient to prevent hyperphosphatemia in anuric patients.
.

  8. NRPB volunteer study: deposition and clearance of inhaled particles

    International Nuclear Information System (INIS)

    Etherington, G.; Smith, J.

    1996-01-01

    At the Board Meeting of the National Radiological Protection Board held on 15 February 1996, approval was given for an experimental study of the deposition and clearance of inhaled particles in the human nasal passage. This is the latest in a series of volunteer biokinetic studies that have been conducted at NRPB since its formation. This article explains the purpose of the study, how ethical approval was obtained, how the study will be performed, what volunteers will be asked to do, and what doses they will receive. Doses will of course be carefully controlled, and will be well below the annual limits set for such experiments. The success of the study is of course crucially dependent on recruitment of a sufficient number of volunteers. The aim of this article is to provide information to anyone who might be interested in volunteering. (UK)

  9. Techniques for blade tip clearance measurements with capacitive probes

    Science.gov (United States)

    Steiner, Alexander

    2000-07-01

    This article presents a proven but advantageous concept for blade tip clearance evaluation in turbomachinery. The system is based on heavy duty probes and a high frequency (HF) and amplifying electronic unit followed by a signal processing unit. Measurements are taken under high temperature and other severe conditions such as ionization. Every single blade can be observed. The signals are digitally filtered and linearized in real time. The electronic set-up is highly integrated. Miniaturized versions of the electronic units exist. The small and robust units can be used in turbo engines in flight. With several probes at different angles in one radial plane further information is available. Shaft eccentricity or blade oscillations can be calculated.

  10. Macrophage Clearance of Apoptotic Cells: A Critical Assessment

    Directory of Open Access Journals (Sweden)

    Siamon Gordon

    2018-01-01

    Full Text Available As the body continues to grow and age, it becomes essential to maintain a balance between living and dying cells. Macrophages and dendritic cells play a central role in discriminating among viable, apoptotic, and necrotic cells, as selective and efficient phagocytes, without inducing inappropriate inflammation or immune responses. A great deal has been learnt concerning clearance receptors for modified and non-self-ligands on potential targets, mediating their eventual uptake, disposal, and replacement. In this essay, we assess current understanding of the phagocytic recognition of apoptotic cells within their tissue environment; we conclude that efferocytosis constitutes a more complex process than simply removal of corpses, with regulatory interactions between the target and effector cells, which determine the outcome of this homeostatic process.

  11. Latency reversal and viral clearance to cure HIV-1.

    Science.gov (United States)

    Margolis, David M; Garcia, J Victor; Hazuda, Daria J; Haynes, Barton F

    2016-07-22

    Research toward a cure for human immunodeficiency virus type 1 (HIV-1) infection has joined prevention and treatment efforts in the global public health agenda. A major approach to HIV eradication envisions antiretroviral suppression, paired with targeted therapies to enforce the expression of viral antigen from quiescent HIV-1 genomes, and immunotherapies to clear latent infection. These strategies are targeted to lead to viral eradication--a cure for AIDS. Paired testing of latency reversal and clearance strategies has begun, but additional obstacles to HIV eradication may emerge. Nevertheless, there is reason for optimism that advances in long-acting antiretroviral therapy and HIV prevention strategies will contribute to efforts in HIV cure research and that the implementation of these efforts will synergize to markedly blunt the effect of the HIV pandemic on society. Copyright © 2016, American Association for the Advancement of Science.

  12. Impaired theophylline clearance in patients with cor pulmonale.

    Science.gov (United States)

    Vicuna, N; McNay, J L; Ludden, T M; Schwertner, H

    1979-01-01

    1 The relationship between serum theophylline concentration and daily dose was studied in 45 patients receiving aminophylline orally and in 36 patients receiving it by constant intravenous infusion. 2 Patients were categorized as uncomplicated chronic obstructive pulmonary disease (COPD) or COPD with cor pulmonale (CP). 3 Serum theophylline concentration relative to daily theophylline dose was significantly higher in patients with COPD plus CP than in patients with COPD alone. 4 Total body clearance of theophylline estimated from data obtained during constant intravenous infusion was significantly lower in COPD plus CP than in patients with COPD alone. 5 We conclude that reduced maintenance doses of theophylline are indicated in patients with COPD when complicated with CP. PMID:760740

  13. 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

  14. Thoracolumbar spine clearance: Clinical examination for patients with distracting injuries.

    Science.gov (United States)

    Cason, Ben; Rostas, Jack; Simmons, Jon; Frotan, Mohammed A; Brevard, Sidney B; Gonzalez, Richard P

    2016-01-01

    The purpose of this study was to prospectively assess the sensitivity of clinical examination to screen for thoracolumbar spine (TLS) injury in awake and alert blunt trauma patients with distracting injuries. From December 2012 to June 2014, all blunt trauma patients older than 13 years were prospectively evaluated as per standard TLS examination protocol at a Level 1 trauma center. Awake and alert patients with Glasgow Coma Scale (GCS) score of 14 or greater underwent clinical examination of the TLS. Clinical examination was performed regardless of distracting injuries. Patients with no complaints of pain or tenderness on examination of the TLS were considered clinically cleared of injury. Patients with distracting injuries, including those clinically cleared and those with complaints of TLS pain or tenderness, underwent computed tomographic scan of the entire TLS. Patients with minor distracting injuries were not considered to have a distracting injury. A total of 950 blunt trauma patients were entered, 530 (56%) of whom had at least one distracting injury. Two hundred nine patients (40%) with distracting injuries had a positive TLS clinical examination result, of whom 50 (25%) were diagnosed with TLS injury. Three hundred twenty-one patients (60%) with distracting injuries were initially clinically cleared, in whom 17 (5%) TLS injuries were diagnosed. There were no missed injuries that required surgical intervention, with only four injuries receiving TLS orthotic bracing. This yielded an overall clinical clearance sensitivity for injury of 75% and sensitivity for clinically significant injury of 89%. In awake and alert blunt trauma patients with distracting injuries, clinical examination is a sensitive screening method for significant TLS injury. Radiologic assessment may be unnecessary for safe clearance of the asymptomatic TLS in patients with distracting injuries. These findings suggest significant potential reduction of both health care cost and patient

  15. Update on macrophage clearance of inhaled micro- and nanoparticles.

    Science.gov (United States)

    Geiser, Marianne

    2010-08-01

    Lung macrophages, that is, the intravascular, interstitial, pleural, and surface macrophages, are part of the mononuclear phagocyte system. They are derived from the hematopoietic stem cell in the bone marrow with the monocytes as their putative precursors. Macrophages residing on the inner surfaces of the lungs and immersed within the lung lining layer, that is, the alveolar and the airway macrophages, are constantly exposed to the environment; it is those cells that are recognized as first line of cellular host defense. Phagocytic uptake of inhaled and deposited particles is the main mechanism to remove insoluble micrometer-sized particles from the lung surfaces, where mucociliary transport, cough, or sneezing fail or are absent. Phagocytosis requires an intact cytoskeleton and is most efficient when mediated by Fc-receptors, but complement and scavenger receptors like MARCO and CD206 are just as important. The main pathway for the clearance of macrophage-associated particles is by mucociliary transport; to a lesser degree and species specific, particle-containing macrophages may reenter into the interstitium and go from there to the lymphatics. Inhaled nanometer-sized particles that deposit along the entire respiratory tract, however, are not efficiently phagocytosed by surface macrophages. Uptake by spontaneous or stimulated (macro-) pinocytosis or electrokinetic's phenomena may become more important. In addition, translocation of nanometer-sized particles into the interstitium and to the blood circulation brings them into contact with other fluids; altered particle properties may influence particle uptake. Moreover, translocated particles may interact with lung macrophage populations that were previously not considered of great significance for the clearance of inhaled particles.

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

    Energy Technology Data Exchange (ETDEWEB)

    Piepsz, A. (Dept. of Radioisotopes, Academic Hospital, VUB Brussels (Belgium) Dept. of Radioisotopes, Hopital Saint-Pierre, Brussels (Belgium)); Pintelon, H. (Dept. of Radioisotopes, Academic Hospital, VUB Brussels (Belgium)); Ham, H.R. (Dept. of Radioisotopes, Hopital Saint-Pierre, Brussels (Belgium))

    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[sup 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[sup 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 [sup 51]Cr-EDTA clearance values. (orig.)

  17. 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

  18. 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...

  19. 12 CFR 220.9 - Clearance of securities, options, and futures.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Clearance of securities, options, and futures..., options, and futures. (a) Credit for clearance of securities. The provisions of this part shall not apply... an option or futures clearing agency for the purpose of meeting the deposit requirements of the...

  20. 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)

  1. 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...

  2. 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.

  3. 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.

  4. Assessments of risk following the inhalation of plutonium oxide using observed lung clearance patterns

    International Nuclear Information System (INIS)

    Ramsden, D.

    1977-10-01

    Dose commitments and risk estimates for the inhalation of plutonium oxide are calculated using the lung clearance patterns observed at AEE Winfrith. These risks are compared with published data on risks arising from a lung clearance based on the ICRP Lung Model. (author)

  5. 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.

  6. 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....

  7. Dopamine plasma clearance is increased in piglets compared to neonates during continuous dopamine infusion

    DEFF Research Database (Denmark)

    Rasmussen, Martin B.; Gramsbergen, Jan Bert; Eriksen, Vibeke R.

    2018-01-01

    clearance was 627.9 mL/kg/minute (interquartile range 452.6–1914.4). Both piglets and neonates showed large interindividual variations in plasma clearance, but the median tended to be lower in neonates (384.9, interquartile range 114.2–480.2 mL/kg/minute). Conclusion: Our results suggest...

  8. 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...

  9. 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...

  10. 77 FR 34391 - Submission for OMB Review; Comment Request Generic Clearance to Conduct Voluntary Customer...

    Science.gov (United States)

    2012-06-11

    ...; Comment Request Generic Clearance to Conduct Voluntary Customer/Partner Surveys SUMMARY: Under the... valid OMB control number. Proposed Collection: Title: Generic Clearance to Conduct Voluntary Customer... customers to determine the kind and quality of services they want and their level of satisfaction with...

  11. Oral human papillomavirus infection incidence and clearance: a systematic review of the literature.

    Science.gov (United States)

    Wood, Zoe C; Bain, Christopher J; Smith, David D; Whiteman, David C; Antonsson, Annika

    2017-04-01

    Subclinical oral human papillomavirus (HPV) infection that persists for decades is likely to precede an HPV-driven squamous cell carcinoma of the head and neck, but little is known about the natural history of oral HPV. We systematically reviewed and abstracted data from nine manuscripts that examined human immunodeficiency virus-negative and cancer-free subjects for oral HPV DNA to determine the pooled baseline prevalence and incidence of newly acquired oral HPV infections, and specifically for HPV-16. We also documented the clearance rate and the median time to clearance, where data existed. Of 3762 individuals, 7.5 % had an oral infection with any HPV type (1.6 % for HPV-16). Meta-regression analysis estimated the 12-month cumulative incidence to be 4.8 % (95 % confidence interval 3.2-7.3 %). The overall oral HPV clearance was reported to be 0-80 % between studies, and the median time to clearance from 6.5 to 18 months. Oral HPV-16 clearance was 43-83 %, and median time to clearance for HPV-16 was 7-22 months. Oral HPV prevalence, incidence and clearance vary considerably between published studies from different geographical regions. Further research is required to identify predictors of persistent oral HPV infection. Measurable baseline prevalence was observed in all studies, as well as non-trivial incidence of newly acquired oral HPV infections and incomplete clearance.

  12. 78 FR 67344 - Highly Qualified Teachers Clearance; Extension of Public Comment Period; Correction

    Science.gov (United States)

    2013-11-12

    ... DEPARTMENT OF EDUCATION Highly Qualified Teachers Clearance; Extension of Public Comment Period....S. Department of Education published a 60-day comment period notice in the Federal Register (Page... Teachers Clearance,'' ED-2013-ICCD-0121. The comment period for this information collection request has...

  13. 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

  14. 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

  15. Effects of ramp negotiation, paving type and shoe sole geometry on toe clearance in young adults.

    Science.gov (United States)

    Thies, S B; Jones, R K; Kenney, L P J; Howard, D; Baker, R

    2011-10-13

    Trips are a major cause of falls and result from involuntary contact of the foot with the ground during the swing phase of gait. Adequate toe clearance during swing is therefore crucial for safe locomotion. To date, little is known about the effects of environmental factors and footwear on toe clearance. This study reports on modulation of toe clearance and toe clearance variability in response to changes in ground inclination, paving type, and shoe sole geometry. Toe clearance and toe clearance variability for ten healthy young adults were calculated two-fold: a) for the commonly-used position on the foremost part of the sole of the shoe and b) for the lowest of a total of 7 sole positions, located between the metatarsals and the toe tip across the entire width of the sole. Utilizing a full-factorial design we found that toe clearance was affected by ground inclination, paving type, and sole geometry regardless of the computational method used (with p-valuesimportance of considering footwear and environmental factors when assessing the risk of tripping. Future work needs to investigate to which extent the same factors affect toe clearance in more vulnerable parts of the population. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Effect of surface-active substance on nasal mucociliary clearance time

    DEFF Research Database (Denmark)

    Outzen, K E; Svane-Knudsen, V

    1993-01-01

    Mucociliary clearance measured by saccharin clearance time is depending on ciliary function and on the physiological characteristics of mucus. The aim of this study was to determine whether the application of surface-active substances changed the mucociliary transport time. Twenty healthy persons...

  17. 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

  18. 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.

  19. 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)

  20. Vest Chest Physiotherapy Airway Clearance is Associated with Nitric Oxide Metabolism

    Directory of Open Access Journals (Sweden)

    Joseph H. Sisson

    2013-01-01

    Full Text Available Background. Vest chest physiotherapy (VCPT enhances airway clearance in cystic fibrosis (CF by an unknown mechanism. Because cilia are sensitive to nitric oxide (NO, we hypothesized that VCPT enhances clearance by changing NO metabolism. Methods. Both normal subjects and stable CF subjects had pre- and post-VCPT airway clearance assessed using nasal saccharin transit time (NSTT followed by a collection of exhaled breath condensate (EBC analyzed for NO metabolites (. Results. VCPT shorted NSTT by 35% in normal and stable CF subjects with no difference observed between the groups. EBC concentrations decreased 68% in control subjects after VCPT (before = 115 ± 32 μM versus after = 37 ± 17 μM; . CF subjects had a trend toward lower EBC . Conclusion. We found an association between VCPT-stimulated clearance and exhaled levels in human subjects. We speculate that VCPT stimulates clearance via increased NO metabolism.

  1. Physiological stability and renal clearance of ultrasmall zwitterionic gold nanoparticles: Ligand length matters

    Directory of Open Access Journals (Sweden)

    Xuhui Ning

    2017-05-01

    Full Text Available Efficient renal clearance has been observed from ultrasmall zwitterionic glutathione-coated gold nanoparticles (GS-AuNPs, which have broad preclinical applications in cancer diagnosis and kidney functional imaging. However, origin of such efficient renal clearance is still not clear. Herein, we conducted head-to-head comparison on physiological stability and renal clearance of two zwitterionic luminescent AuNPs coated with cysteine and glycine-cysteine (Cys-AuNPs and Gly-Cys-AuNPs, respectively. While both of them exhibited similar surface charges and the same core sizes, additional glycine slightly increased the hydrodynamic diameter of the AuNPs by 0.4 nm but significantly enhanced physiological stability of the AuNPs as well as altered their clearance pathways. These studies indicate that the ligand length, in addition to surface charges and size, also plays a key role in the physiological stability and renal clearance of ultrasmall zwitterionic inorganic NPs.

  2. Numerical Analysis of the Influence of Clearance on Stress State and Contact Pressure in Plain Bearings

    Directory of Open Access Journals (Sweden)

    Vasile Cojocaru

    2017-12-01

    Full Text Available In the analysis of plain bearings by finite element method it is important to model as closely to real state the aspects that influence the stress and contact pressure: the loading mode, the properties of the materials, the lubrication system, the clearance between the shaft and the bearing body, the evolution in time of clearance correlated with the wear, etc. In order to study the effect of the clearance on the stress state, a plain bearing with nominal diameter d=40 mm was modeled. The contact pressure and the equivalent stress were computed for six discrete values of clearance, range from c=0 to c=0.3 mm. It has been shown that the increase of clearance generates an increase of the equivalent stress and contact pressure. The growth rate is higher for contact pressure, due to the decrease of the contact surface between the shaft and the bearing body

  3. Physiological stability and renal clearance of ultrasmall zwitterionic gold nanoparticles: Ligand length matters

    Science.gov (United States)

    Ning, Xuhui; Peng, Chuanqi; Li, Eric S.; Xu, Jing; Vinluan, Rodrigo D.; Yu, Mengxiao; Zheng, Jie

    2017-05-01

    Efficient renal clearance has been observed from ultrasmall zwitterionic glutathione-coated gold nanoparticles (GS-AuNPs), which have broad preclinical applications in cancer diagnosis and kidney functional imaging. However, origin of such efficient renal clearance is still not clear. Herein, we conducted head-to-head comparison on physiological stability and renal clearance of two zwitterionic luminescent AuNPs coated with cysteine and glycine-cysteine (Cys-AuNPs and Gly-Cys-AuNPs), respectively. While both of them exhibited similar surface charges and the same core sizes, additional glycine slightly increased the hydrodynamic diameter of the AuNPs by 0.4 nm but significantly enhanced physiological stability of the AuNPs as well as altered their clearance pathways. These studies indicate that the ligand length, in addition to surface charges and size, also plays a key role in the physiological stability and renal clearance of ultrasmall zwitterionic inorganic NPs.

  4. Research on the effect of wear-ring clearances to the performance of centrifugal pump

    International Nuclear Information System (INIS)

    Zhao, W G; Li, Y B; Wang, X Y; Sun, J P; Wu, G X

    2012-01-01

    In order to study the effect of wear-ring clearance on the performance of centrifugal pump, based on the Reynolds Time-Averaged N-S equations and RNG k-ε turbulence model, a centrifugal pump was simulated with three variable styles of the wear-rings: Only the clearance of the front wear-ring was changed, only the clearance of the back wear-ring was changed and both were changed. Numerical results agree well with the experimental results. In the three changing styles of the clearance, the variable of the clearance of front wear-ring has the most influence on the performance of centrifugal pump. The existence of wear-ring not only has an effect on the volumetric loss of the centrifugal pump, but also on the performance of the centrifugal pump. Relative to the experimental studies, numerical simulation methods have some advantages, such as low cost, fast and efficient, and easy to get the detailed structure of the internal flow characteristics, so it has been widely used in the fluid machinery study. In order to study the effect of wear-ring clearance on the performance of centrifugal pump, based on the Reynolds Time-Averaged N-S equations and RNG k-ε turbulence model, a centrifugal pump was simulated with three variable styles of the wear-rings: Only the clearance of the front wear-ring was changed, only the clearance of the back wear-ring was changed and both were changed. Numerical results agree well with the experimental results. In the three changing styles of the clearance, the variable of the clearance of front wear-ring has the most influence on the performance of centrifugal pump.

  5. 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

  6. 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

  7. Airway clearance techniques used by people with cystic fibrosis in the UK.

    Science.gov (United States)

    Hoo, Z H; Daniels, T; Wildman, M J; Teare, M D; Bradley, J M

    2015-12-01

    To describe the current use of airway clearance techniques among people with cystic fibrosis (CF) in the UK, and the baseline characteristics for users of different airway clearance techniques. Analysis of the UK CF Registry 2011 data. All people with CF in the UK aged ≥11 years (n=6372). Of the 6372 people on the UK CF registry in 2011, 89% used airway clearance techniques. The most commonly used primary techniques were forced expiratory techniques (28%) and oscillating positive expiratory pressure (PEP) (23%). Postural drainage and high-frequency chest wall oscillation were used by 4% and 1% of people with CF, respectively. The male:female ratio of individuals who used exercise as their primary airway clearance technique was 2:1, compared with 1:1 for other techniques. Individuals with more severe lung disease tended to use devices such as non-invasive ventilation or high-frequency chest wall oscillation. Forced expiratory techniques and oscillating PEP are the most common airway clearance techniques used by people with CF in the UK, and postural drainage and high-frequency chest wall oscillation are the least common techniques. This is significant in terms of planning airway clearance technique trials, where postural drainage has been used traditionally as the comparator. The use of airway clearance techniques varies between countries, but the reasons for these differences are unknown. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  8. 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.

  9. Effect of off-bottom clearance on properties of pellets produced by melt pelletization.

    Science.gov (United States)

    Heng, P W; Wan, L S; Wong, T W

    1999-01-01

    This study examines the influence of off-bottom clearance on size and size distribution of pellets produced during melt pelletization at different postmelt impeller speeds and binder concentrations using lactose and polyethylene glycol. Melt pelletization of lactose powder 450 M in an 8-liter highshear mixer, the floor of which was made of polytetrafluoroethylene (PTFE), was carried out with polyethylene glycol 3000 as the meltable binder. Erosion of the PTFE floor of the mixer occurred with time of use and this caused a change in the off-bottom clearance. The findings showed that with a wider clearance, the size distribution of pellets was wider and pellets were much larger. These changes were the results of changes in the mixing intensity and impact frequency of the mass in relation to the eddies formed within the off-bottom clearance. The changes were not associated with the reduction in the circulating material load by entrapment into the off-bottom clearance. In the melt pelletization process, the quality of product was higher if the clearance was kept to a minimum. The off-bottom clearance was best measured at the beginning of each pelletization run because the PTFE floor of the mixer was prone to erosion.

  10. A bodyweight-dependent allometric exponent for scaling clearance across the human life-span.

    Science.gov (United States)

    Wang, Chenguang; Peeters, Mariska Y M; Allegaert, Karel; Blussé van Oud-Alblas, Heleen J; Krekels, Elke H J; Tibboel, Dick; Danhof, Meindert; Knibbe, Catherijne A J

    2012-06-01

    To explore different allometric equations for scaling clearance across the human life-span using propofol as a model drug. Data from seven previously published propofol studies ((pre)term neonates, infants, toddlers, children, adolescents and adults) were analysed using NONMEM VI. To scale clearance, a bodyweight-based exponential equation with four different structures for the exponent was used: (I) 3/4 allometric scaling model; (II) mixture model; (III) bodyweight-cut-point separated model; (IV) bodyweight-dependent exponent model. Model I adequately described clearance in adults and older children, but overestimated clearance of neonates and underestimated clearance of infants. Use of two different exponents in Model II and Model III showed significantly improved performance, but yielded ambiguities on the boundaries of the two subpopulations. This discontinuity was overcome in Model IV, in which the exponent changed sigmoidally from 1.35 at a hypothetical bodyweight of 0 kg to a value of 0.56 from 10 kg onwards, thereby describing clearance of all individuals best. A model was developed for scaling clearance over the entire human life-span with a single continuous equation, in which the exponent of the bodyweight-based exponential equation varied with bodyweight.

  11. The steady state: is it a neglectable or a compulsory condition for determining renal clearance

    International Nuclear Information System (INIS)

    Bongartz, W.; Kuni, H.; Ridder, H.W.; Naber, K.

    1975-01-01

    The first part of the paper reviews critically the whole-body counter technique with falling blood activity level for measuring renal clearance. It is proved that the methodological assumption that the classic clearance formula in its differential mode can be applied is not fulfilled under routine conditions for several reasons. Therefore, that procedure has to be judged as a ''clearance-equivalent'' method. The second part describes the development of a steady-state clearance procedure to a practicable method. By using a subcutaneous (s.c.) autogenous blood depot of 51 Cr-EDTA the authors achieve a quasi constant level of blood activity which is nearly equivalent to that achievable by means of a continuous infusion technique. The third part describes a further development of this method into a ''total clearance'' method by means of a new and quantitative two-compartment analysis. The authors discuss the conditions under which the main criterion of a steady state (input equal to output) is realized and show that (1) the steady state is a condition absolutely necessary for the exact determination of renal clearance, and (2) the standard condition of constant blood level is neither sufficient to prove a steady state nor essential for a mass balance. This conception of determining renal clearance indirectly by means of a complete two-compartment analysis seems to have advantages over competitive procedures. At a reasonable expense of hardware and personnel this method involves minimal discomfort to the patient. (author)

  12. 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.

  13. 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

  14. Relationship between phosphorus and creatinine clearance in peritoneal dialysis: clinical implications.

    Science.gov (United States)

    Sedlacek, M; Dimaano, F; Uribarri, J

    2000-11-01

    Elevated serum phosphorus levels are associated with increased morbidity and mortality in dialysis patients. To study the determinants of serum phosphorus levels and phosphorus clearance, we measured phosphorus concentrations in 24-hour collections of dialysate and residual urine output during routine urea kinetics in 56 peritoneal dialysis patients. Dietary records were used to estimate oral phosphorus intake, and the net gastrointestinal absorption of phosphorus was determined measuring the amount of phosphorus excreted in 24 hours. Dialysate to plasma ratios of phosphorus and creatinine were very similar, and the peritoneal clearances of phosphorus and creatinine correlated well and were of the same magnitude. High transporters in the peritoneal equilibration test had greater phosphorus and creatinine clearances than low transporters. In patients with residual urine output, the renal clearances of phosphorus and creatinine also correlated well. Comparing two groups of patients with a similar Kt/V of 2 and greater but different levels of creatinine clearance, either greater or less than 60 L/wk, the patients with the greater creatinine clearance also had a greater phosphorus clearance (7.0 +/- 2.2 versus 4.3 +/- 0.7 mL/min/1.73 m(2)) and significantly lower serum phosphorus levels (4.8 +/- 0.9 versus 5.9 +/- 1.4 mg/dL) despite a greater daily amount of phosphorus absorption (490 +/- 190 versus 336 +/- 100 mg/d). In summary, creatinine clearance measurements provide a good estimate of phosphorus clearance and how much dietary phosphorus and therefore protein can be tolerated.

  15. Clearance of inhaled particles from the human nose

    Energy Technology Data Exchange (ETDEWEB)

    Proctor, D.F.; Andersen, I.; Lundqvist, G.

    1973-01-01

    Nasal mucus flow transports particles at a rate of 5 mm/min (albeit much slower rates have been recorded). Transport is not affected by humidity. Anatomy of the nose shows air passage decreases to approx. 0.3 cm/sup 2/ in the anterior nares. This point has the highest air velocity (highest impaction) of entire respiratory tract. Immediately posterior (main nasal passage), the stream cross-section widens while the stream remains narrow. Opportunity for adsorption of gases is greatest in this low-velocity, high surface air passage (mucus passes through here). Subsequent bending and narrowing of airway toward nasopharnyx offers a second impaction area. Resistance could not predict gas absorption, as this absorption occurs mostly in low-resistance passages. The nasal mucus stream ends on the posterior aspect of the soft palate where wiping action of swallowing clears it. The anterior spot with highest air velocity is not ciliated. Clearance is possibly by anterior motion (e.g., sneezing) rather than by swallowing which would take longer.

  16. Harnessing Apoptotic Cell Clearance to Treat Autoimmune Arthritis

    Directory of Open Access Journals (Sweden)

    Philippe Saas

    2017-10-01

    Full Text Available Early-stage apoptotic cells possess immunomodulatory properties. Proper apoptotic cell clearance during homeostasis has been shown to limit subsequent immune responses. Based on these observations, early-stage apoptotic cell infusion has been used to prevent unwanted inflammatory responses in different experimental models of autoimmune diseases or transplantation. Moreover, this approach has been shown to be feasible without any toxicity in patients undergoing allogeneic hematopoietic cell transplantation to prevent graft-versus-host disease. However, whether early-stage apoptotic cell infusion can be used to treat ongoing inflammatory disorders has not been reported extensively. Recently, we have provided evidence that early-stage apoptotic cell infusion is able to control, at least transiently, ongoing collagen-induced arthritis. This beneficial therapeutic effect is associated with the modulation of antigen-presenting cell functions mainly of macrophages and plasmacytoid dendritic cells, as well as the induction of collagen-specific regulatory CD4+ T cells (Treg. Furthermore, the efficacy of this approach is not altered by the association with two standard treatments of rheumatoid arthritis (RA, methotrexate and tumor necrosis factor (TNF inhibition. Here, in the light of these observations and recent data of the literature, we discuss the mechanisms of early-stage apoptotic cell infusion and how this therapeutic approach can be transposed to patients with RA.

  17. Evaluation of terrain geomorphometric characteristics for ground clearance charts production

    Directory of Open Access Journals (Sweden)

    Mirko A. Borisov

    2011-01-01

    Full Text Available Geomorphometric exploration applied in the military terrain analysis is based on the GIS methodology of spatial analyses and is related primarily to military terrain analyses. It includes relief assessment aiming at producing ground clearance charts for the analysis of terrain maneuverability and its deployment, cover and concealment possibilities. An evaluation analysis of geomorphological parameters was performed for the Avala test area using a few terrain parameters (visibility, terrain aspect and slope as well as some terrain qualitative categories (e.g. vegetation density. Terrain slope Slope and aspect are morphometric terrain parameters that can be derived directly from the DTM using some GIS operations. Slope is the first derivative of a surface and has both magnitude and direction. Slope is perhaps the most important aspect of the surface form, since surfaces are formed completely of slopes, and slope angles control the gravitational force available for geomorphic work. Mathematically, the tangent of the slope angle is the first derivative of altitude, and it is a tangent or percent slope as this surface parameter is generally referred to. Slope is defined at each point as the slope of a plane tangent to the surface at that point. In practice, however, slope is generally measured over a finite distance, especially when data are obtained from a contour map. Terrain aspect Aspect is also the first derivative of a surface and has both magnitude and direction. The term aspect is defined as the direction of the biggest slope vector on the tangent plane projected onto the horizontal plane. Aspect is the bearing (or azimuth of the slope direction, and its angle ranges from 0 to 360°. Analyses of terrain slope and ground clearance for military forces The analysis of land assessment of the Avala test area included the definition of relief categories in relation to cover and concealment purposes with the aim to include the geomorphological basis

  18. Modeling bacterial clearance using stochastic-differential equations.

    Science.gov (United States)

    Atalla, Ashraf; Jeremic, Aleksandar

    2010-01-01

    Capillary - tissue fluid exchange is controlled by the blood pressure in the capillary and the osmotic pressure of blood (pressure of the tissue fluid outside the capillaries). In this paper, we develop a mathematical model to simulate the movement of bacteria into and within a capillary segment. The model is based on Fokker-Planck equation and Navier-Stocks equations that accounts for different boundary conditions. Also, we model the transportation through capillary walls by means of anisotropic diffusivity that depends on the pressure difference across the capillary walls. By solving the model with a numerical method, it was possible to predict the concentration of bacteria at points within the capillary. However, numerical analysis consumes computational time and resources. To efficiently simulate the bacterial clearance, we propose a segmentation model that is based on breaking the capillary network into smaller sections with pre-defined properties in order to reduce the overall computational time. The proposed model shows a great reduction in computational time and provides accurate results when compared to the numerical analysis.

  19. Effect of Cilia Beat Frequency on Mucociliary Clearance

    Directory of Open Access Journals (Sweden)

    Sedaghat M. H.

    2016-12-01

    Full Text Available Background: The airway surface liquid (ASL, which is a fluid layer coating the interior epithelial surface of the bronchi and bronchiolesis, plays an important defensive role against foreign particles and chemicals entering lungs. Objective: Numerical investigation has been employed to solve two-layer model consisting of mucus layer as a viscoelastic fluid and periciliary liquid layer as a Newtonian fluid to study the effects of cilia beat frequency (CBF at various amounts of mucus properties on muco-ciliary transport problem. Methods: Hybrid finite difference-lattice Boltzmann-method (FB-LBM has been used to solve the momentum equations and to simulate cilia forces, and also the PCLmucus interface more accurately, immersed boundary method (IBM has been employed. The main contribution of the current study is to use an Oldroyd-B model as the constitutive equation of mucus. Results: Our results show that increasing CBF and decreasing mucus viscosity ratio have great effects on mucus flow, but the effect of viscosity ratio is more significant. The results also illustrate that the relation between cilia beat frequency and mean mucus velocity is almost linear and it has similar behavior at different values of viscosity ratio. Conclusion: Numerical investigation based on hybrid IB-FD-LBM has been used to study the effect of CBF at various mounts of mucus viscosity ratio on the muco-ciliary clearance. The results showed that the effect of viscosity ratio on the muco-ciliary transport process is more significant compared with CBF.

  20. Nonlinear Dynamics Response of a Planar Mechanism with Two Driving Links and Prismatic Pair Clearance

    Directory of Open Access Journals (Sweden)

    Lijuan Wu

    2017-01-01

    Full Text Available The influence of the joint clearance on the dynamic response of a planar mechanism with two driving links and prismatic pair clearance is investigated under variable input speeds of the system. The simulation model was built with a nonlinear impact model. The normal contact force is characterized by Hertz contact theory and an energy dissipation term. A tangential friction force is involved in the simulation model based on Coulomb’s friction law. The simulation results indicate that the largest Lyapunov exponents are dependent on the clearance size and the input speed.

  1. 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)

  2. Long-term follow-up of patients with spontaneous clearance of hepatitis C: does viral clearance mean cure?

    LENUS (Irish Health Repository)

    Iqbal, M

    2017-06-01

    Up to 40% of patients with hepatitis C virus (HCV) antibodies are negative for HCV RNA at initial evaluation. If there is a risk of viral re-activation, long term follow-up is required with attendant financial, psychological and medical implications. We investigated the risk of re-activation in the Irish anti-D cohort. Information was obtained from the national hepatitis C database which includes data on patients infected by anti-D immunoglobulin in two large outbreaks, 1977-9 and 1991-94. As part of a screening programme, starting in 1994, 64,907 females exposed to anti-D immunoglobulin were evaluated. Three hundred and forty-seven were found to be antibody positive but HCV RNA negative at initial assessment. 93% had subsequent RNA tests. There was no evidence of HCV recurrence in patients whose infection resolved spontaneously. It appears that two initial sequential negative results for HCV RNA are sufficient to confirm spontaneous viral clearance and probable cure of hepatitis C virus infection.

  3. Sulfadoxine-pyrimethamine monotherapy in Tanzanian children gives rapid parasite clearance but slow fever clearance that is improved by chloroquine in combination therapy

    DEFF Research Database (Denmark)

    Tarimo, D S; Minjas, J N; Bygbjerg, I C

    2002-01-01

    paracetamol (PCM) (n=38) in children with uncomplicated malaria. Over 72 h, there were eight (20.5%) treatment failures in the CQ group but none in the other groups. Although not significant (P > 0.1), irrespective of resistance CQ alone had a shorter median survival time to fever clearance than SP alone (54...... vs. 60 h). SP plus CQ had a highly significantly shorter median survival time to fever clearance than SP alone (48 vs. 60 h) (P PCM (72 h) than SP alone (48 h). Irrespective...

  4. Measurement of the plasma clearance of urographic contrast media for the determination of glomerular filtration rate

    International Nuclear Information System (INIS)

    O'Reilly, P.H.; Jones, D.A.; Farah, N.B.

    1988-01-01

    Further experience with a new method to determine glomerular filtration rate is presented. The method depends on measurement by an x-ray fluorescence technique of the plasma disappearance of the injected iodine in standard nonionic radiographic contrast media used during excretory urography. The results of comparison of contrast clearance with /sup 99m/technetium-diethylenetriaminepentaacetic acid clearance in 33 cases showed excellent agreement with a correlation coefficient of 0.95. Reproducibility of the contrast clearance method was confirmed by repeated examination of 10 plasma samples at weekly intervals for 6 weeks, the results of which showed no significant differences. The contrast clearance technique for the measurement of glomerular filtration rate during excretory urography is simple, quick and accurate, and merits further development

  5. Optical Method for Real-Time Turbine Blade Tip Clearance Measurement, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Monitoring and controlling blade tip clearance of high pressure turbines are important for maintaining the integrity of the engine during its operating points and...

  6. 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).

  7. 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)

  8. Increased Hepatic Insulin Clearance After Roux-en-Y Gastric Bypass

    DEFF Research Database (Denmark)

    Bojsen-Møller, Kirstine N; Dirksen, Carsten; Jørgensen, Nils B

    2013-01-01

    Context:Roux-en-Y gastric bypass (RYGB) improves glucose tolerance and ameliorates fasting hyperinsulinemia within days after surgery. Improvements in hepatic insulin sensitivity and insulin clearance could contribute importantly to these effects.Objective:The objective of the investigation...... was to study changes in insulin clearance after RYGB.Design:This was a prospective study of fasting hepatic insulin clearance and, in a subgroup of patients, postprandial insulin clearance after a meal test before and 1 week, 3 months, and 1 year after RYGB.Setting:The study was conducted at Hvidovre Hospital...... (Hvidovre, Denmark).Patients:Patients included 2 groups of obese RYGB-patients: 1) type 2 diabetes (T2D) group: 32 patients with T2D (meal test, n = 13), 2) normal glucose tolerance (NGT) group: 32 patients with NGT (meal test, n = 12).Intervention:The intervention was RYGB.Main Outcome Measure...

  9. 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.

  10. Anatomical factors predicting lower calyceal stone clearance after extracorporeal shockwave lithotripsy

    Directory of Open Access Journals (Sweden)

    M. Khan

    2016-06-01

    Conclusions: This study shows that lower infundibular length and width are significant anatomical factors in determining stone clearance following ESWL treatment of lower calyceal stones and these should be assessed before planning the treatment for lower calyceal stones.

  11. Dual roles for hepatic lectin receptors in the clearance of chilled platelets

    DEFF Research Database (Denmark)

    Rumjantseva, Viktoria; Grewal, Prabhjit K; Wandall, Hans H

    2009-01-01

    Rapid chilling causes glycoprotein-Ib (GPIb) receptors to cluster on blood platelets. Hepatic macrophage beta(2) integrin binding to beta-N-acetylglucosamine (beta-GlcNAc) residues in the clusters leads to rapid clearance of acutely chilled platelets after transfusion. Although capping the beta-G...... transfusion. Inhibition of chilled platelet clearance by both beta(2) integrin and Ashwell-Morell receptors may afford a potentially simple method for storing platelets in the cold.......Rapid chilling causes glycoprotein-Ib (GPIb) receptors to cluster on blood platelets. Hepatic macrophage beta(2) integrin binding to beta-N-acetylglucosamine (beta-GlcNAc) residues in the clusters leads to rapid clearance of acutely chilled platelets after transfusion. Although capping the beta......-Morell receptor binding, become increasingly involved in platelet removal. Macrophages rapidly removed a large fraction of transfused platelets independent of their storage conditions. With prolonged platelet chilling, hepatocyte-dependent clearance further diminishes platelet recovery and survival after...

  12. 75 FR 52803 - Agency Information Collection Activities: Requests for Comments; Clearance of Renewed Approval of...

    Science.gov (United States)

    2010-08-27

    ... 87,769 certified mechanics, repair stations, and air carriers authorized to perform maintenance... Activities: Requests for Comments; Clearance of Renewed Approval of Information Collection: Maintenance, Preventative Maintenance, Rebuilding and Alteration AGENCY: Federal Aviation Administration (FAA), DOT. ACTION...

  13. NUMERICAL SIMULATIONS FOR THE CASE OF RIGID ROTATING KINEMATIC COUPLING WITH BIG CLEARANCE

    Directory of Open Access Journals (Sweden)

    Jan-Cristian GRIGORE

    2010-10-01

    Full Text Available In this paper an algorithm based on [1] [2] are numerical simulations, achieving generalized coordinates of motion, positions, speeds of a rigid rotating kinematic coupling with big clearance in joint, case without friction

  14. 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

    observed in the experiments with 20 mussels was most likely a result of a combination of reduced current velocity within the aggregated mussels, a current velocity-dependent change of siphon orientation, and attachment of the mussels at current velocities less than 1.2 m/sec, whereas in experiments with 3......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...

  15. Hepatitis C Virus Reinfection and Spontaneous Clearance of Reinfection--the InC3 Study

    NARCIS (Netherlands)

    Sacks-Davis, Rachel; Grebely, Jason; Dore, Gregory J.; Osburn, William; Cox, Andrea L.; Rice, Thomas M.; Spelman, Timothy; Bruneau, Julie; Prins, Maria; Kim, Arthur Y.; McGovern, Barbara H.; Shoukry, Naglaa H.; Schinkel, Janke; Allen, Todd M.; Morris, Meghan; Hajarizadeh, Behzad; Maher, Lisa; Lloyd, Andrew R.; Page, Kimberly; Hellard, Margaret; Lauer, Georg; Hahn, Judy; Alavi, Maryam; Bouchard, Rachel; Evans, Jennifer; Grady, Bart; Aneja, Jasneet; Teutsch, Suzy; White, Bethany; Wells, Brittany; Zang, Geng; Applegate, Tanya; Matthews, Gail; Yeung, Barbara; van de Laar, Thijs; Erin Prince, Leslie; Roy, Elise; Bates, Anna; Enriquez, Jarliene; Chow, Sammy; Park, Ju; McCredie, Luke; Aitken, Campbell; Bowden, Scott; Higgs, Peter; Tracy, Lilly; Briceno, Alya

    2015-01-01

    We aimed to characterize the natural history of hepatitis C virus (HCV) reinfection and spontaneous clearance following reinfection (reclearance), including predictors of HCV reclearance. Data were synthesized from the 9 prospective cohorts of the International Collaboration of Incident Human

  16. 75 FR 68829 - Agency Information Collection Activities: Comment Request; Generic Survey Clearance for the...

    Science.gov (United States)

    2010-11-09

    ... and STEM workforce. NSF funds grants, contracts, and cooperative agreements to colleges, universities... accordance with the 2001, 2005, and 2008 OMB TOCs, NSF requests separate stand-alone clearance (and...

  17. 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...

  18. 77 FR 27486 - Notice of Continuance for General Clearance for Guidelines, Applications and Reporting Forms

    Science.gov (United States)

    2012-05-10

    ... NATIONAL FOUNDATION FOR THE ARTS AND HUMANITIES Notice of Continuance for General Clearance for... Foundation for the Arts and Humanities. ACTION: Notice, request for comments, collection of information... Agencies, museums, libraries, institutions of higher education, library and museum professional...

  19. 75 FR 22631 - Notice of Continuance for General Clearance for Guidelines, Applications, and Reporting Forms

    Science.gov (United States)

    2010-04-29

    ... NATIONAL FOUNDATION FOR THE ARTS AND HUMANITIES Notice of Continuance for General Clearance for Guidelines, Applications, and Reporting Forms AGENCY: Institute of Museum and Library Services. ACTION... of higher education, library and museum professional associations, and museum and library...

  20. Correlation of Cystatin-C with Glomerular Filtration Rate by Inulin Clearance in Pregnancy

    Science.gov (United States)

    Saxena, Aditi R.; Karumanchi, S. Ananth; Fan, Shu-Ling; Horowitz, Gary L.; Seely, Ellen W.

    2012-01-01

    Objective To test utility of cystatin-C as a marker of glomerular filtration rate during pregnancy, we performed serial correlations with inulin clearance during pregnancy and postpartum. Methods Twelve subjects received inulin infusions and serum cystatin-C at three time points. Pearson's correlation coefficient was calculated. Results Cystatin-C levels ranged 0.66 to 1.48 mg/L during pregnancy, and 0.72 to 1.26 mg/L postpartum. Inulin clearance ranged 130 to 188 ml/min during pregnancy, and 110 to 167 ml/min postpartum. Cystatin-C did not correlate with inulin clearance at any time point. Conclusion Serum cystatin-C did not correlate with inulin clearance during pregnancy or postpartum. PMID:22008011

  1. 77 FR 36330 - Agency Information Collection Activities: Requests for Comments; Clearance of Renewed Approval of...

    Science.gov (United States)

    2012-06-18

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Agency Information Collection Activities: Requests for Comments; Clearance of Renewed Approval of Information Collection: Pilot Schools AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice and request for comments. SUMMARY: In...

  2. 77 FR 20093 - Agency Information Collection Activities: Requests for Comments; Clearance of Renewed Approval of...

    Science.gov (United States)

    2012-04-03

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Agency Information Collection Activities: Requests for Comments; Clearance of Renewed Approval of Information Collection: Pilot Schools AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice and request for comments. SUMMARY: In...

  3. Lactate production and clearance in exercise. Effects of training. A mini-review

    DEFF Research Database (Denmark)

    Stallknecht, B; Vissing, J; Galbo, H

    1998-01-01

    conditions. Due to influence on hormonal response, mitochondrial oxidative capacity and fiber recruitment, training diminishes glycogenolysis and lactate production. Training also increases lactate clearance. This reflects increased hepatic capacity for gluconeogenesis as well as increased lactate transport...

  4. Clearance of Sclerostin, Osteocalcin, Fibroblast Growth Factor 23, and Osteoprotegerin by Dialysis

    DEFF Research Database (Denmark)

    Carlson, Nicholas; Mortensen, Ole H.; Axelsen, Mette

    2017-01-01

    Introduction: Fibroblast growth factor (FGF23), sclerostin, osteocalcin, and osteoprotegerin are important factors that control mineral bone metabolism. End-stage renal disease is associated with the pronounced dysregulation of mineral bone metabolism; however, the impact and clearance of mineral...... bone metabolism factors during dialysis remain largely undescribed. Methods: In a cross-sectional study, 10 chronic hemodialysis patients were treated with hemodialysis for 8 h using a high-flux filter and a dialysate bath of 50% calculated total body water continuously recycled at a rate of 500 m...... mineral bone metabolism factors were observed. Conclusions: The intradialytic clearance of osteocalcin, FGF23, sclerostin, and osteoprotegerin occurs; however, only clearance of FGF23 is directly correlated with the ultrafiltration rate. The effects of dialytic clearance on mineral bone metabolism are...

  5. Evaluating photonuclear activation for clearance of decommissioned medical linear accelerators

    International Nuclear Information System (INIS)

    Shida, Koichi; Isobe, Tomonori; Takada, Kenta

    2012-01-01

    assigned as 40 K, 208 T1, 214 Pb, 214 Bi and 228 Ac; the short half-life nuclides can be assigned as 59 Fe, 58 Co, 185 W and 196 Au; and the long half-life nuclides can be assigned as 54 Mn and 60 Co. These results show that photonuclear activation of parts is important in regard to clearance. Currently, there are no regulations that specify criteria for evaluating radioactivation. Such criteria are needed to establish suitable protocols for the clearance of radioactivated materials. (author)

  6. 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

  7. Error modelling and experimental validation of a planar 3-PPR parallel manipulator with joint clearances

    DEFF Research Database (Denmark)

    Wu, Guanglei; Bai, Shaoping; Kepler, Jørgen Asbøl

    2012-01-01

    This paper deals with the error modelling and analysis of a 3-PPR planar parallel manipulator with joint clearances. The kinematics and the Cartesian workspace of the manipulator are analyzed. An error model is established with considerations of both configuration errors and joint clearances. Using...... this model, the upper bounds and distributions of the pose errors for this manipulator are established. The results are compared with experimental measurements and show the effectiveness of the error prediction model....

  8. 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

  9. Effects of lung volume on clearance of solutes from the air spaces of lungs

    International Nuclear Information System (INIS)

    Peterson, B.T.; James, H.L.; McLarty, J.W.

    1988-01-01

    Several investigators have shown that the clearance rate of aerosolized 99mTc-labeled diethylenetriamine pentaacetate (DTPA, mol wt = 492, radius = 0.6 nm) from the air spaces of the lungs of humans and experimental animals increases with lung volume. To further investigate this phenomenon we performed a compartmental analysis of the 2-h clearance of DTPA from the lungs of anesthetized sheep using a new method to more accurately correct for the effects of DTPA recirculation. This analysis showed that the DTPA clearance in eight sheep ventilated with zero end-expired pressure was best described by a one-compartment model with a clearance rate of 0.42 +/- 0.15%/min. Ventilating eight sheep with an end-expired pressure of 10 cmH 2 O throughout the study increased the end-expired volume 0.4 +/- 0.1 liter BTPS and created a clearance curve that was best described by a two-compartment model. In these sheep 56 +/- 16% of the DTPA cleared from the lungs at a rate of 7.9 +/- 2.9%/min. The remainder cleared at a rate similar to that measured in the sheep ventilated with zero end-expired pressure (0.35 +/- 0.18%/min). Additional control and lung inflation experiments were performed using /sup 99m/Tc-labeled human serum albumin (mol wt = 66,000, radius = 3.6 nm). In six control sheep ventilated with zero end-expired pressure the albumin clearance was best described by a one-compartment model with a clearance rate of 0.06 +/- 0.02%/min. The clearance rate in six sheep with increased lung volume was slightly larger (0.09 +/- 0.02, P less than 0.05) but was well described by a one-compartment model

  10. Solute clearance measurement in the assessment of dialysis adequacy among African continuous ambulatory peritoneal dialysis patients

    Directory of Open Access Journals (Sweden)

    Aliyu Abdu

    2015-01-01

    Full Text Available Solute clearance measurement is an objective means of quantifying the dose of peritoneal dialysis (PD. Despite continued debate on the interpretation and precise prognostic value of small solute clearance in PD patients, guidelines based on solute clearance values are common in clinical practice. There is limited information on the solute clearance indices and PD adequacy parameters among this predominantly low socioeconomic status PD population. We investigated the solute clearance among continuous ambulatory peritoneal dialysis (CAPD patients at the Charlotte Maxeke Johannesburg Academic Hospital and its relationship with other parameters of PD adequacy. Seventy patients on CAPD were studied in this cross-sectional study. Solute clearance was assessed using urea clearance (Kt/V. Linear regression analysis was used to determine factors associated with solute clearance, while analysis of variance was used to test the influence of weekly Kt/V on blood pressure (BP, hemoglobin (Hb and other biochemical parameters. The mean age of the study population was 37.9 ± 12.4 years, 43% were females and 86% were black Africans. The mean duration on CAPD was 19.7 ± 20.8 months. Mean systolic and diastolic BP were 144 ± 28 and 92 ± 17 mm Hg, respectively. The mean Hb was 11.1 ± 2.2 g/dL and the mean weekly Kt/V was 1.7 ± 0.3. Factors like systolic BP, Hb level, serum levels of cholesterol, calcium, phosphate, parathyroid hormone and albumin were not significantly associated with the weekly Kt/V. We conclude that the dose of PD received by the majority of our patients in terms of the weekly Kt/V is within the recommended values and that this finding is significant considering the low socioeconomic background of our patients. There is no significant association between Kt/V and other indices of dialysis adequacy.

  11. 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)

  12. 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)

  13. Effects of irradiation on nasal mucociliary clearance in head and neck cancer patients

    OpenAIRE

    Gupta, S. C.; Chandra, S.; Singh, M.

    2006-01-01

    A prospective longitudinal study was conducted on fifty patients of histopathologically confirmed head and neck cancer with the main aim to assess the nasal mucociliary clearance, pre-and post-irradiation; and to compare the findings with the healthy non-irradiated age and sex-matched controls. All the patients underwent saccharin particle test for nasal mucociliary clearance before commencement of radiation therapy and again within 6 months of completion of radiation therapy. The difference ...

  14. 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...

  15. 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

  16. MO-F-16A-08: Have An Impact On More Patients From Your Ideas And Inventions

    International Nuclear Information System (INIS)

    Morton, R

    2014-01-01

    Purpose: To inform physicists how to obtain an FDA 510(k) clearance for the innovations they use in their facility and to make those ideas widely available to patients throughout the U.S. Methods: Give advice from 20 years experience of assisting in well over 100 successful 510(k) clearances. Results: Learn how to develop a 510(k) submission. Conclusion: Many physicists, physicians and radiation therapists have developed innovations that that are helpful to the patients in their institution. But, many of these innovations deserve to be made available to patients throughout the United States. The author, a Certified Radiological Physicist and former FDA employee, has consulted for over twenty years for inventors, start-ups and established medical device manufacturers to bring new devices to market in the U.S. and to assist them to established FDA compliant quality systems for manufacturing. In this presentation the audience will learn the important points for deciding to go forward with obtaining a Premarket Notification clearance [also known as a 510(k) clearance] to legally market a medical device in the United States. The FDA has published guidelines for submitting a 510(k) application. However, the methods used to efficiently develop the documentation for submission and to obtain clearance in the shortest possible time comes from the author's experience in assisting well over one hundred successful 510(k) clearances.Whether you want to start your own company or to market your idea to an established medical device manufacturer, the value of your innovation increases with a documented 510(k) clearance from FDA

  17. Effect of Turbine Axial Nozzle-Wheel Clearance on Performance of Mark 25 Torpedo Power Plant

    Science.gov (United States)

    Hoyt, Jack W.; Kottas, Harry

    1948-01-01

    Investigations were made of the turbine from a Mark 25 torpedo to determine the performance of the unit with three different turbine nozzles at various axial nozzle-wheel clearances. Turbine efficiency with a reamed nondivergent nozzle that uses the axial clearance space for gas expansion was little affected by increasing the axial running clearance from 0.030 to 0.150 inch. Turbine efficiency with cast nozzles that expanded the gas inside the nozzle passage was found to be sensitive to increased axial nozzle-wheel clearance. A cast nozzle giving a turbine brake efficiency of 0.525 at an axial running clearance of 0.035 inch gave a brake efficiency of 0.475 when the clearance was increased to 0.095 inch for the same inlet-gas conditions and blade-jet speed ratio. If the basis for computing the isentropic power available to the turbine is the temperature inside the nozzle rather then the temperature in the inlet-gas pipe, an increase in turbine efficiency of about 0.01 is indicated.

  18. 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.

  19. Dynamic analysis of planar mechanical systems with clearance joints using a new nonlinear contact force model

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xupeng; Liu, Geng; Ma, Shangjun [Northwestern Polytechnical University, Xi' an (China)

    2016-04-15

    We investigated the dynamic behavior of planar mechanical systems with clearance joints. First, the contact effect in clearance joint was studied using a new nonlinear contact force model, and the rationality of this model was verified by the results of numerical simulations, which are based on a journal and bearing contact model. Then, the dynamic characteristics of a planar slider-crank mechanism with clearance were analyzed based on the new nonlinear contact force model, and the friction effect of clearance joint was also considered using modified Coulomb friction model. Finally, the numerical results of the influence of clearance size on the acceleration of slider are presented, and compared with the published experimental results. The numerical and experimental results show that the new nonlinear contact force model presented in this paper is an effective method to predict the dynamic behavior of planar mechanical system with clearance joints, and appears to be suitable for a wide range of impact situations, especially with low coefficient of restitution.

  20. 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

    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...... 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...

  1. 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

  2. Metabolism of oxycodone in human hepatocytes from different age groups and prediction of hepatic plasma clearance

    Directory of Open Access Journals (Sweden)

    Timo eKorjamo

    2012-01-01

    Full Text Available Oxycodone is commonly used to treat severe pain in adults and children. It is extensively metabolized in the liver in adults, but the maturation of metabolism is not well understood. Our aim was to study the metabolism of oxycodone in cryopreserved human hepatocytes from different age groups (3 days, 2 and 5 months, 4 years, adult pool and predict hepatic plasma clearance of oxycodone using these data. Oxycodone (0.1, 1 and 10 µM was incubated with hepatocytes for 4 hours, and 1 µM oxycodone also with CYP3A inhibitor ketoconazole (1 µM. Oxycodone and noroxycodone concentrations were determined at several time points with liquid chromatography-mass spectrometry. In vitro clearance of oxycodone was used to predict hepatic plasma clearance, using the well-stirred model and published physiological parameters. Noroxycodone was the major metabolite in all batches and ketoconazole inhibited the metabolism markedly in most cases. A clear correlation between in vitro oxycodone clearance and CYP3A4 activity was observed. The predicted hepatic plasma clearances were typically much lower than the published median total plasma clearance from pharmacokinetic studies. In general, this in vitro to in vivo extrapolation method provides valuable information on the maturation of oxycodone metabolism that can be utilized in the design of clinical pharmacokinetic studies in infants and young children.

  3. Decreasing Radiation Exposure in Pediatric Trauma Related to Cervical Spine Clearance: A Quality Improvement Project.

    Science.gov (United States)

    Waddell, Valerie Ann; Connelly, Susan

    Quality improvement project. Reduce the amount of radiation exposure in the pediatric trauma population 5 years of age and older in relation to cervical spine clearance. The evaluation of pediatric cervical spine injuries must be accurate and timely to avoid missed injuries. The difficult clinical examination in pediatric trauma patients necessitates the use of radiologic examinations to avoid missing catastrophic injuries. However, exposure to radiation at an early age increases the pediatric patients' risk of developing cancer (R. A. ). A retrospective chart review was conducted to assess radiation exposure in pediatric patients requiring evaluation for cervical spine clearance. Surgical staff and emergency department physicians received education on the risks related to pediatric radiation exposure and information related to the institution's diagnostic trends for cervical spine clearance. An algorithm was then developed to assist with determining the necessary imaging study for cervical spine clearance. Radiation exposure was monitored following initial education and use of the algorithm to determine its effect on radiation exposure. The retrospective chart review identified cervical spine computed tomography (CT) in 34%, with an average radiation exposure of 3.5 mSv. Following education and introduction of an algorithm, 18% of patients underwent CT for cervical spine clearance with an average radiation exposure of 3.2 mSv, representing a 47% decrease in the use of CT. Staff education and the use of an algorithm show promise in the reduction of radiation exposure and provide safe, effective clearance of the cervical spine in pediatric trauma.

  4. 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

  5. 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.

  6. Four Decades of Forest Persistence, Clearance and Logging on Borneo

    Science.gov (United States)

    Gaveau, David L. A.; Sloan, Sean; Molidena, Elis; Yaen, Husna; Sheil, Doug; Abram, Nicola K.; Ancrenaz, Marc; Nasi, Robert; Quinones, Marcela; Wielaard, Niels; Meijaard, Erik

    2014-01-01

    The native forests of Borneo have been impacted by selective logging, fire, and conversion to plantations at unprecedented scales since industrial-scale extractive industries began in the early 1970s. There is no island-wide documentation of forest clearance or logging since the 1970s. This creates an information gap for conservation planning, especially with regard to selectively logged forests that maintain high conservation potential. Analysing LANDSAT images, we estimate that 75.7% (558,060 km2) of Borneo's area (737,188 km2) was forested around 1973. Based upon a forest cover map for 2010 derived using ALOS-PALSAR and visually reviewing LANDSAT images, we estimate that the 1973 forest area had declined by 168,493 km2 (30.2%) in 2010. The highest losses were recorded in Sabah and Kalimantan with 39.5% and 30.7% of their total forest area in 1973 becoming non-forest in 2010, and the lowest in Brunei and Sarawak (8.4%, and 23.1%). We estimate that the combined area planted in industrial oil palm and timber plantations in 2010 was 75,480 km2, representing 10% of Borneo. We mapped 271,819 km of primary logging roads that were created between 1973 and 2010. The greatest density of logging roads was found in Sarawak, at 0.89 km km−2, and the lowest density in Brunei, at 0.18 km km−2. Analyzing MODIS-based tree cover maps, we estimate that logging operated within 700 m of primary logging roads. Using this distance, we estimate that 266,257 km2 of 1973 forest cover has been logged. With 389,566 km2 (52.8%) of the island remaining forested, of which 209,649 km2 remains intact. There is still hope for biodiversity conservation in Borneo. Protecting logged forests from fire and conversion to plantations is an urgent priority for reducing rates of deforestation in Borneo. PMID:25029192

  7. 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

  8. Four decades of forest persistence, clearance and logging on Borneo.

    Directory of Open Access Journals (Sweden)

    David L A Gaveau

    Full Text Available The native forests of Borneo have been impacted by selective logging, fire, and conversion to plantations at unprecedented scales since industrial-scale extractive industries began in the early 1970s. There is no island-wide documentation of forest clearance or logging since the 1970s. This creates an information gap for conservation planning, especially with regard to selectively logged forests that maintain high conservation potential. Analysing LANDSAT images, we estimate that 75.7% (558,060 km2 of Borneo's area (737,188 km2 was forested around 1973. Based upon a forest cover map for 2010 derived using ALOS-PALSAR and visually reviewing LANDSAT images, we estimate that the 1973 forest area had declined by 168,493 km2 (30.2% in 2010. The highest losses were recorded in Sabah and Kalimantan with 39.5% and 30.7% of their total forest area in 1973 becoming non-forest in 2010, and the lowest in Brunei and Sarawak (8.4%, and 23.1%. We estimate that the combined area planted in industrial oil palm and timber plantations in 2010 was 75,480 km2, representing 10% of Borneo. We mapped 271,819 km of primary logging roads that were created between 1973 and 2010. The greatest density of logging roads was found in Sarawak, at 0.89 km km-2, and the lowest density in Brunei, at 0.18 km km-2. Analyzing MODIS-based tree cover maps, we estimate that logging operated within 700 m of primary logging roads. Using this distance, we estimate that 266,257 km2 of 1973 forest cover has been logged. With 389,566 km2 (52.8% of the island remaining forested, of which 209,649 km2 remains intact. There is still hope for biodiversity conservation in Borneo. Protecting logged forests from fire and conversion to plantations is an urgent priority for reducing rates of deforestation in Borneo.

  9. 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

  10. 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

  11. Prediction of metabolic drug clearance in humans: in vitro-in vivo extrapolation vs allometric scaling.

    Science.gov (United States)

    Shiran, M R; Proctor, N J; Howgate, E M; Rowland-Yeo, K; Tucker, G T; Rostami-Hodjegan, A

    2006-07-01

    Previously in vitro-in vivo extrapolation (IVIVE) with the Simcyp Clearance and Interaction Simulator has been used to predict the clearance of 15 clinically used drugs in humans. The criteria for the selection of the drugs were that they are used as probes for the activity of specific cytochromes P450 (CYPs) or have a single CYP isoform as the major or sole contributor to their metabolism and that they do not exhibit non-linear kinetics in vivo. Where data were available for the clearance of the drugs in at least three animal species, the predictions from IVIVE have now been compared with those based on allometric scaling (AS). Adequate data were available for estimating oral clearance (CLp.o.) in 9 cases (alprazolam, sildenafil, caffeine, clozapine, cyclosporine, dextromethorphan, midazolam, omeprazole and tolbutamide) and intravenous clearance in 6 cases (CLi.v.) (cyclosporine, diclofenac, midazolam, omeprazole, theophylline and tolterodine). AS predictions were based on five different methods: (1) simple allometry (clearance versus body weight); (2) correction for maximum life-span potential (CL x MLP); (3) correction for brain weight (CL x BrW); (4) the use of body surface area; and (5) the rule of exponents. A prediction accuracy was indicated by mean-fold error and the Pearson product moment correlation coefficient. Predictions were considered successful if the mean-fold error was error range: 1.02-4.00). All five AS methods were accurate in 13, 11, 10, 10 and 14 cases, respectively. However, in some cases the error of AS exceeded fivefold. On the basis of the current results, IVIVE is more reliable than AS in predicting human clearance values for drugs mainly metabolized by CYP450 enzymes. This suggests that the place of AS methods in pre-clinical drug development warrants further scrutiny.

  12. Mucociliary and long-term particle clearance in airways of patients with immotile cilia

    Directory of Open Access Journals (Sweden)

    Ziegler-Heitbrock Löms

    2006-01-01

    Full Text Available Abstract Spherical monodisperse ferromagnetic iron oxide particles of 1.9 μm geometric and 4.2 μm aerodynamic diameter were inhaled by seven patients with primary ciliary dyskinesia (PCD using the shallow bolus technique, and compared to 13 healthy non-smokers (NS from a previous study. The bolus penetration front depth was limiting to the phase1 dead space volume. In PCD patients deposition was 58+/-8 % after 8 s breath holding time. Particle retention was measured by the magnetopneumographic method over a period of nine months. Particle clearance from the airways showed a fast and a slow phase. In PCD patients airway clearance was retarded and prolonged, 42+/-12 % followed the fast phase with a mean half time of 16.8+/-8.6 hours. The remaining fraction was cleared slowly with a half time of 121+/-25 days. In healthy NS 49+/-9 % of particles were cleared in the fast phase with a mean half time of 3.0+/-1.6 hours, characteristic of an intact mucociliary clearance. There was no difference in the slow clearance phase between PCD patients and healthy NS. Despite non-functioning cilia the effectiveness of airway clearance in PCD patients is comparable to healthy NS, with a prolonged kinetics of one week, which may primarily reflect the effectiveness of cough clearance. This prolonged airway clearance allows longer residence times of bacteria and viruses in the airways and may be one reason for increased frequency of infections in PCD patients.

  13. Influence of Tip Clearance on Forced Convection Heat Transfer of a Finned Plate in a Duct

    International Nuclear Information System (INIS)

    Park, Haekyun; Chung, Bumjin

    2014-01-01

    Optimizations are required for a proper enhancement of cooling capability. An important phenomenological consideration is to be reveals for a finned plate in a duct. Due to the high friction near the fin region and low friction near the wall region, the forced flow tends to bypass from fin region to wall region. The bypass flow increases the net flow and enhances the heat transfer for a moderate tip clearance which is defined by the distance from the tip of the fin and the wall. Meanwhile for a large tip clearance, most of the flow bypasses and does not contribute the heat transfer and impairs the heat transfer. This study is a preliminary numerical study on the influence of the tip clearance on the heat transfer of the finned plate in a duct. The study aimed at supporting an experimental research exploring the phenomena for a very small tip clearance. Thus material properties and test conditions were chosen to meet the experimental conditions. It investigated the phenomena at Pr of 2,014 and ReS of 58.3. In order to investigate the small tip clearance phenomena, a simple numerical scheme was developed using a commercial CFD code. A case with the same experimental condition was tested using the numerical scheme and the error was about 12%. The results show the clear evidence of the flow bypass from the fin region to wall region, which impair the heat removal capacity of the finned plate in a duct. The study has the relevance with the reactor cavity cooling system performance enhancement activities in the VHTR. The numerical scheme will be tested for narrower and wider tip clearances and find an optimal tip clearance

  14. 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

  15. The effects of walking speed on minimum toe clearance and on the temporal relationship between minimum clearance and peak swing-foot velocity in unilateral trans-tibial amputees.

    Science.gov (United States)

    De Asha, Alan R; Buckley, John G

    2015-04-01

    Minimum toe clearance is a critical gait event because it coincides with peak forward velocity of the swing foot, and thus, there is an increased risk of tripping and falling. Trans-tibial amputees have increased risk of tripping compared to able-bodied individuals. Assessment of toe clearance during gait is thus clinically relevant. In able-bodied gait, minimum toe clearance increases with faster walking speeds, and it is widely reported that there is synchronicity between when peak swing-foot velocity and minimum toe clearance occur. There are no such studies involving lower-limb amputees. To determine the effects of walking speed on minimum toe clearance and on the temporal relationship between clearance and peak swing-foot velocity in unilateral trans-tibial amputees. Cross-sectional. A total of 10 trans-tibial participants walked at slow, customary and fast speeds. Minimum toe clearance and the timings of minimum toe clearance and peak swing-foot velocity were determined and compared between intact and prosthetic sides. Minimum toe clearance was reduced on the prosthetic side and, unlike on the intact side, did not increase with walking speed increase. Peak swing-foot velocity consistently occurred (~0.014 s) after point of minimum toe clearance on both limbs across all walking speeds, but there was no significant difference in the toe-ground clearance between the two events. The absence of speed related increases in minimum toe clearance on the prosthetic side suggests that speed related modulation of toe clearance for an intact limb typically occurs at the swing-limb ankle. The temporal consistency between peak foot velocity and minimum toe clearance on each limb suggests that swing-phase inter-segmental coordination is unaffected by trans-tibial amputation. The lack of increase in minimum toe clearance on the prosthetic side at higher walking speeds may potentially increase risk of tripping. Findings indicate that determining the instant of peak swing

  16. Reduced Postvasectomy Semen Analysis Testing With the Implementation of Special Clearance Parameters.

    Science.gov (United States)

    Bieniek, Jared M; Fleming, Tyler B; Clark, Joseph Y

    2015-09-01

    To determine the applicability of postvasectomy special clearance parameters (<100,000 nonmotile sperm/mL on semen analysis) suggested by the American Urological Association and to define the associated cost savings with avoidance of further testing. We retrospectively reviewed the cohort of men undergoing vasectomy from December 2009 to August 2012 at a single institution. Patient demographics and postvasectomy semen analysis (PVSA) results were collected for clearance parameter comparisons. During the study period, 230 patients underwent vasectomy with a mean ± SD age of 36.4 ± 6.5 years. Among the cohort, 83.5% were married and 95.2% had one or more children. The initial PVSA was completed by 111 (48.3%) patients at a mean of 17.8 weeks (range 4-45) following vasectomy. Sperm was identified on initial PVSA in 40 patients (36.0%); 1 patient was found to have motile sperm. Of 39 patients, 38 (97.4%) with nonmotile sperm on PVSA could be cleared to cease other contraceptives based on the most recent clearance guidelines. For those completing an initial PVSA, postvasectomy clearance increased from 64.0% to 98.2% representing a potential cost savings of $2356 in repeat semen testing. Postvasectomy contraceptive clearance can be greatly increased when rare nonmotile sperm parameters are included although postvasectomy semen testing compliance remains poor. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. The influence of annular seal clearance to the critical speed of the multistage pump

    International Nuclear Information System (INIS)

    Wang, J; Shen, H P; Ye, X Y; Hu, J N; Feng, Y N

    2013-01-01

    In the multistage pump of high head, pressure difference in two ends of annular seal clearance and rotor eccentric would produce the sealing fluid force, the effect of which can be expressed by a damping and stiffness coefficient. It has a great influence on the critical speed of the rotor system. In order to research the influence of the annular seal to the rotor system, this paper used CFD method to conduct the numerical simulation for the flow field of annular seal clearance. The radial and tangential forces were obtained to calculate the annular dynamic coefficients. Also dynamic coefficient were obtained by Matlab. The rotor system was modeled using ANSYS finite software and the critical speed with and without annular seal clearance were calculated. The result shows: annular seal's fluid field is under the comprehensive effect of pressure difference and rotor entrainment. Due to the huge pressure difference in front annular seal, fluid flows under pressure difference; the low pressure difference results in the more obvious effect on the clearance field in back annular seal. The first order critical speed increases greatly with the annular seal clearance; while the average growth rate of the second order critical speed is only 3.2%; the third and fourth critical speed decreases little. Based on the above result, the annular seal has great influence to the first order speed, while has little influence on the rest

  18. Clearance of aerosolized 99mTc-diethylenetriaminepentacetate before and after smoke inhalation

    International Nuclear Information System (INIS)

    Clark, W.R.; Grossman, Z.D.; Ritter-Hrncirik, C.; Warner, F.

    1988-01-01

    The pulmonary clearance of aerosolized /sup 99m/Tc-diethylenetriaminepentacetate (DTPA) was studied in mongrel dogs immediately after exposure to wood smoke to see if a sensitive, objective way of assessing the degree of pulmonary injury might be found. Animals were studied in four groups as follows: control, following five minutes, two minutes, and 15 seconds of smoke exposure. Chest roentgenograms and 133 Xe scans were taken before and after smoke exposure. The DTPA clearance was more sensitive in detecting injury than either of these imaging techniques. The DTPA clearance rates increased in a dose responsive way following smoke inhalation: 2.4 percent and 12.1 percent excreted per minute for control animals and those exposed to five minutes of smoke, respectively. Seven patients in a clinical trial of DTPA following smoke exposure are described; their DTPA clearance rates were all normal, although five were active cigarette smokers. Despite encouraging results in animal experiments, DTPA clearance studies may be of little practical value in the clinical setting of acute inhalation injury

  19. 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.

  20. 51Cr-EDTA plasma clearance in severe renal failure determined by one plasma sample

    DEFF Research Database (Denmark)

    Kamper, A L; Nielsen, S L

    1989-01-01

    Two hundred and thirty-four measurements of standard 51Cr-EDTA plasma clearance were made in 50 patients with severe chronic renal failure. Based on these data two calculation methods were attempted using one plasma sample drawn 24 h after injection of 51Cr-EDTA. One of the methods used the 'one...... sample clearance' formulas disregarding exact time of plasma sampling. This method might provide values 3.1 ml/min below or 2.9 ml/min above the established method of total 51Cr-EDTA plasma clearance, and would thus provide insufficient agreement. In the other method an estimate of plasma activity...... at zero-time was derived from injected dose and body surface area. This method might provide values 1.5 ml/min below or 0.8 ml/min above the established method of 51Cr-EDTA plasma clearance, which would be acceptable for clinical purposes. It is concluded that exact plasma clearance of 51Cr-EDTA in severe...

  1. Subcellular clearance and accumulation of Huntington disease protein: A mini-review

    Directory of Open Access Journals (Sweden)

    Ting eZhao

    2016-04-01

    Full Text Available Huntington’s disease (HD is an autosomal dominant, progressive neurodegenerative disease caused by an expanded polyglutamine (polyQ tract in the N-terminal region of mutant huntingtin (mHtt. As a result, mHtt forms aggregates that are abundant in the nuclei and processes of neuronal cells. Although the roles of mHtt aggregates are still debated, the formation of aggregates points to deficient clearance of mHtt in brain cells. Since the accumulation of mHtt is a prerequisite for its neurotoxicity, exploring the mechanisms for mHtt accumulation and clearance would advance our understanding of HD pathogenesis and help us develop treatments for HD. We know that the ubiquitin-proteasome system and autophagy play important roles in clearing mHtt; however, how mHtt preferentially accumulates in neuronal nuclei and processes remains unclear. Studying the clearance of mHtt in neuronal cells is a challenge because neurons are morphologically and functionally polarized, which means the turnover of mHtt may be distinct in different cellular compartments. In this review, we discuss our current knowledge about the clearance and accumulation of mHtt and strategies of examining mHtt clearance and accumulation in different subcellular regions

  2. Stone clearance in lower pole nephrolithiasis after extra corporeal shock wave lithotripsy – the controversy continues

    Directory of Open Access Journals (Sweden)

    Akhtar Sobia

    2003-01-01

    Full Text Available Abstract Background To determine factors influencing the clearance of fragments after extra-corporeal shock wave lithotripsy (ESWL for lower pole calyceal (LPC stones. Methods In the period between July 1998 and Oct 2001, 100 patients with isolated lower polar calyceal calculi ≤ 20 mm, in patients aged ≥ 14 years, were included in the study. Intravenous urograms (IVU were reviewed to define the LPC anatomy (width of the infundibulum and pelvicalyceal angle. Study end points i.e. stone free status; number of shock waves used and number of sessions were correlated with variables like LPC anatomy, body mass index and stone size. Results At three months follow up the clearance for stone size ≤ 10 mm, 11–15 mm and 16–20 mm were 95, 96 and 90% respectively. Patients with acute LPC (90° had stone clearance of 94 and 100% respectively. For the infundibular width of 4 mm, it was 100%. For body mass index (BMI less than and > 30 kg/m2, the stone clearance was 92 and 95% respectively. Conclusions There is a trend towards more ESWL sessions and shock wave requirement in patients with acute pelvi-calyceal angle and narrow infundibulum but it is not statistically significant. Size (≤ 20 mm and BMI has no relation with stone clearance. With modern lithotripter, stones up to 20 mm could primarily be treated by ESWL, irrespective of an un-favorable lower polar calyceal anatomy and body habitus.

  3. Persistence or Clearance of Human Papillomavirus Infections in Women in Ouro Preto, Brazil

    Science.gov (United States)

    Miranda, P. M.; Silva, N. N. T.; Pitol, B. C. V.; Silva, I. D. C. G.; Lima-Filho, J. L.; Carvalho, R. F.; Stocco, R. C.; Beçak, W.; Lima, A. A.

    2013-01-01

    Persistent high-risk (HR) human papillomavirus (HPV) infection is necessary for development of precursor lesions and cervical cancer. We investigate persistence and clearance of HPV infections and cofactors in unvaccinated women. Cervical samples of 569 women (18–75 years), received for routine evaluation in the Health Department of Ouro Preto, Brazil, were collected and subjected to PCR (MY09/11 or GP5+/6+ primers), followed by RFLP or sequencing. All women were interviewed to collect sociodemographic and behavioral information. Viral infection persistence or clearance was reevaluated after 24 months and was observed in 59.6% and 40.4% of women, respectively. HPVs 16, 33, 59, 66, 69, and 83 (HR) were the most persistent types whereas HPVs 31, 45, and 58 were less persistent. Clearance or persistence did not differ between groups infected by HPVs 18, 53, and 67. In low-risk (LR) types, HPV 6 infected samples were associated with clearance, while HPV 11, 61, 72, or 81 infected samples were persistent in the follow-up. No statistically significant association was detected between persistent HPV infections and sociodemographic and behavioral characteristics analyzed. To study persistence or clearance in HPV infection allows the identification of risk groups, cofactors, and strategies for prevention of cervical cancer. PMID:24298551

  4. Rotating coherent flow structures as a source for narrowband tip clearance noise from axial fans

    Science.gov (United States)

    Zhu, Tao; Lallier-Daniels, Dominic; Sanjosé, Marlène; Moreau, Stéphane; Carolus, Thomas

    2018-03-01

    Noise from axial fans typically increases significantly as the tip clearance is increased. In addition to the broadband tip clearance noise at the design flow rate, narrowband humps also associated with the tip flow are observed in the far-field acoustic spectra at lower flow rate. In this study, both experimental and numerical methods are used to shed more light on the noise generation mechanism of this narrowband tip clearance noise and provide a unified description of this source. Unsteady aeroacoustic predictions with the Lattice-Boltzmann Method (LBM) are successfully compared with experiment. Such a validation allows using LBM data to conduct a detailed modal analysis of the pressure field for detecting rotating coherent flow structures which might be considered as noise sources. As previously found in ring fans the narrowband humps in the far-field noise spectra are found to be related to the tip clearance noise that is generated by an interaction of coherent flow structures present in the tip region with the leading edge of the impeller blades. The visualization of the coherent structures shows that they are indeed part of the unsteady tip clearance vortex structures. They are hidden in a complex, spatially and temporally inhomogeneous flow field, but can be recovered by means of appropriate filtering techniques. Their pressure trace corresponds to the so-called rotational instability identified in previous turbomachinery studies, which brings a unified picture of this tip-noise phenomenon for the first time.

  5. Planar rigid-flexible coupling spacecraft modeling and control considering solar array deployment and joint clearance

    Science.gov (United States)

    Li, Yuanyuan; Wang, Zilu; Wang, Cong; Huang, Wenhu

    2018-01-01

    Based on Nodal Coordinate Formulation (NCF) and Absolute Nodal Coordinate Formulation (ANCF), this paper establishes rigid-flexible coupling dynamic model of the spacecraft with large deployable solar arrays and multiple clearance joints to analyze and control the satellite attitude under deployment disturbance. Considering torque spring, close cable loop (CCL) configuration and latch mechanisms, a typical spacecraft composed of a rigid main-body described by NCF and two flexible panels described by ANCF is used as a demonstration case. Nonlinear contact force model and modified Coulomb friction model are selected to establish normal contact force and tangential friction model, respectively. Generalized elastic force are derived and all generalized forces are defined in the NCF-ANCF frame. The Newmark-β method is used to solve system equations of motion. The availability and superiority of the proposed model is verified through comparing with numerical co-simulations of Patran and ADAMS software. The numerical results reveal the effects of panel flexibility, joint clearance and their coupling on satellite attitude. The effects of clearance number, clearance size and clearance stiffness on satellite attitude are investigated. Furthermore, a proportional-differential (PD) attitude controller of spacecraft is designed to discuss the effect of attitude control on the dynamic responses of the whole system.

  6. 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.

  7. Persistence or clearance of human papillomavirus infections in women in Ouro Preto, Brazil.

    Science.gov (United States)

    Miranda, P M; Silva, N N T; Pitol, B C V; Silva, I D C G; Lima-Filho, J L; Carvalho, R F; Stocco, R C; Beçak, W; Lima, A A

    2013-01-01

    Persistent high-risk (HR) human papillomavirus (HPV) infection is necessary for development of precursor lesions and cervical cancer. We investigate persistence and clearance of HPV infections and cofactors in unvaccinated women. Cervical samples of 569 women (18-75 years), received for routine evaluation in the Health Department of Ouro Preto, Brazil, were collected and subjected to PCR (MY09/11 or GP5+/6+ primers), followed by RFLP or sequencing. All women were interviewed to collect sociodemographic and behavioral information. Viral infection persistence or clearance was reevaluated after 24 months and was observed in 59.6% and 40.4% of women, respectively. HPVs 16, 33, 59, 66, 69, and 83 (HR) were the most persistent types whereas HPVs 31, 45, and 58 were less persistent. Clearance or persistence did not differ between groups infected by HPVs 18, 53, and 67. In low-risk (LR) types, HPV 6 infected samples were associated with clearance, while HPV 11, 61, 72, or 81 infected samples were persistent in the follow-up. No statistically significant association was detected between persistent HPV infections and sociodemographic and behavioral characteristics analyzed. To study persistence or clearance in HPV infection allows the identification of risk groups, cofactors, and strategies for prevention of cervical cancer.

  8. Decrease in xenon clearance during response to cold, dry air: Problems of interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Naclerio, R.M.; Fisher, C.; Civelek, C.A.; Bartenfelder, D.; Koller, D.; La France, N.D. (Johns Hopkins Univ. School of Medicine, Baltimore, MD (USA))

    1990-02-01

    In order to increase our understanding of the nasal response to cold, dry air (CDA), we studied changes in xenon clearance as an indicator of nasal blood flow. Eight individuals previously shown to respond to CDA had measurements of xenon clearance made in the left inferior turbinate before, during, and after a 15-minute exposure to either CDA (-7 degrees C to 0 degrees C, less than 10% relative humidity) or room air. The half-life in seconds for xenon clearance on the day when CDA was inhaled was 56 +/- 6, 41 +/- 5, and 110 +/- 31, before, during, and 10 minutes after challenge, respectively. On the control day, with subjects breathing room air, the equivalent measurements of half-life in seconds were 54 +/- 8, 41 +/- 6, and 42 +/- 4, respectively. Xenon clearance was prolonged significantly (p less than .01) after exposure to CDA during the clinical response. The interpretation of the change in xenon clearance as an indicator of nasal blood flow is discussed.

  9. Effect of increases in lung volume on clearance of aerosolized solute from human lungs

    International Nuclear Information System (INIS)

    Marks, J.D.; Luce, J.M.; Lazar, N.M.; Wu, J.N.; Lipavsky, A.; Murray, J.F.

    1985-01-01

    To study the effect of increases in lung volume on solute uptake, we measured clearance of /sup 99m/Tc-diethylenetriaminepentaacetic acid (Tc-DTPA) at different lung volumes in 19 healthy humans. Seven subjects inhaled aerosols (1 micron activity median aerodynamic diam) at ambient pressure; clearance and functional residual capacity (FRC) were measured at ambient pressure (control) and at increased lung volume produced by positive pressure [12 cmH 2 O continuous positive airway pressure (CPAP)] or negative pressure (voluntary breathing). Six different subjects inhaled aerosol at ambient pressure; clearance and FRC were measured at ambient pressure and CPAP of 6, 12, and 18 cmH 2 O pressure. Six additional subjects inhaled aerosol at ambient pressure or at CPAP of 12 cmH 2 O; clearance and FRC were determined at CPAP of 12 cmH 2 O. According to the results, Tc-DTPA clearance from human lungs is accelerated exponentially by increases in lung volume, this effect occurs whether lung volume is increased by positive or negative pressure breathing, and the effect is the same whether lung volume is increased during or after aerosol administration. The effect of lung volume must be recognized when interpreting the results of this method

  10. Clearance of materials resulting from the use of radionuclides in medicine, industry and research

    International Nuclear Information System (INIS)

    1998-02-01

    It has long been recognized that the use of sources of radiation should be regulated. The recommended regulatory approach is based on a system of notification and authorization exemplified by the IAEA International Basic Safety Standards for Protection Against Ionizing Radiation and for the Safety of Radiation Sources (BSS). However, some types of radiation source do not meet to be subject to regulatory control because they can only give rise to trivial radiation hazards. Such sources may be exempted or cleared from the requirements of regulatory control. Exemption applies to radiation sources which do not enter the regulatory control regime, while clearance is relevant to radiation sources which were within the regulatory regime but can be released because they present an insignificant risk to health. It is the latter situation which is the subject of this publication. While the emphasis of the report is on providing guidance on the clearance process and on methods for determining clearance leaves, taking account of site specific factors as appropriate, a set of conservatively derived generic clearance levels is also presented. These are expected to be of considerable help to users of small quantities of radionuclides in laboratories and hospitals and their regulators. They can be used, taking due account of the associated notes of caution, as reference levels for determining when clearance is the appropriate option for disposing of the materials

  11. 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

  12. Endurance training inhibits insulin clearance and IDE expression in Swiss mice.

    Directory of Open Access Journals (Sweden)

    José M Costa-Júnior

    Full Text Available Endurance training improves peripheral insulin sensitivity in the liver and the skeletal muscle, but the mechanism for this effect is poorly understood. Recently, it was proposed that insulin clearance plays a major role in both glucose homeostasis and insulin sensitivity. Therefore, our goal was to determine the mechanism by which endurance training improves insulin sensitivity and how it regulates insulin clearance in mice.Mice were treadmill-trained for 4 weeks at 70-80% of maximal oxygen consumption (VO2 max for 60 min, 5 days a week. The glucose tolerance and the insulin resistance were determined using an IPGTT and an IPITT, respectively, and the insulin decay rate was calculated from the insulin clearance. Protein expression and phosphorylation in the liver and the skeletal muscle were ascertained by Western blot.Trained mice exhibited an increased VO2 max, time to exhaustion, glucose tolerance and insulin sensitivity. They had smaller fat pads and lower plasma concentrations of insulin and glucose. Endurance training inhibited insulin clearance and reduced expression of IDE in the liver, while also inhibiting insulin secretion by pancreatic islets. There was increased phosphorylation of both the canonical (IR-AKT and the non-canonical (CaMKII-AMPK-ACC insulin pathways in the liver of trained mice, whereas only the CaMKII-AMPK pathway was increased in the skeletal muscle.Endurance training improved glucose homeostasis not only by increasing peripheral insulin sensitivity but also by decreasing insulin clearance and reducing IDE expression in the liver.

  13. 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.

  14. 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 sepsis and septic shock patients is 7.5%.

  15. Impaired mucociliary clearance in allergic rhinitis patients is related to a predisposition to rhinosinusitis.

    Science.gov (United States)

    Vlastos, Ioannis; Athanasopoulos, Ioannis; Mastronikolis, Nicholas S; Panogeorgou, Theodora; Margaritis, Vassilios; Naxakis, Stefanos; Goumas, Panos D

    2009-04-01

    Although mucociliary clearance has been shown to be impaired in patients with allergic rhinitis and chronic rhinosinusitis, its exact role in relation to a predisposition to rhinosinusitis is unknown. To investigate this possible association, we conducted a prospective study of 125 patients with allergic rhinitis. Of this group, 23 patients were classified as being sinusitis-prone based on their history of antibiotic consumption for the treatment of rhinosinusitis; the remaining 102 patients were deemed to be not sinusitis-prone. The saccharine test was used to evaluate mucociliary clearance in all patients. Several variables-age, sex, smoking habits, rhinitis severity, and medication history-were examined. We found that the sinusitis-prone patients had a significantly greater mucociliary clearance time than did those who were not prone (median: 15 and 12 min, respectively; p = 0.02). No other statistically significant differences were seen between the 2 groups with respect to any other variables that might have affected mucociliary clearance. We conclude that impaired mucociliary clearance in allergic rhinitis patients is associated with a predisposition to rhinosinusitis.

  16. Fault Diagnosis of Internal Combustion Engine Valve Clearance Using the Impact Commencement Detection Method

    Science.gov (United States)

    Jiang, Zhinong; Wang, Zijia; Zhang, Jinjie

    2017-01-01

    Internal combustion engines (ICEs) are widely used in many important fields. The valve train clearance of an ICE usually exceeds the normal value due to wear or faulty adjustment. This work aims at diagnosing the valve clearance fault based on the vibration signals measured on the engine cylinder heads. The non-stationarity of the ICE operating condition makes it difficult to obtain the nominal baseline, which is always an awkward problem for fault diagnosis. This paper overcomes the problem by inspecting the timing of valve closing impacts, of which the referenced baseline can be obtained by referencing design parameters rather than extraction during healthy conditions. To accurately detect the timing of valve closing impact from vibration signals, we carry out a new method to detect and extract the commencement of the impacts. The results of experiments conducted on a twelve-cylinder ICE test rig show that the approach is capable of extracting the commencement of valve closing impact accurately and using only one feature can give a superior monitoring of valve clearance. With the help of this technique, the valve clearance fault becomes detectable even without the comparison to the baseline, and the changing trend of the clearance could be trackable. PMID:29244722

  17. Fault Diagnosis of Internal Combustion Engine Valve Clearance Using the Impact Commencement Detection Method.

    Science.gov (United States)

    Jiang, Zhinong; Mao, Zhiwei; Wang, Zijia; Zhang, Jinjie

    2017-12-15

    Internal combustion engines (ICEs) are widely used in many important fields. The valve train clearance of an ICE usually exceeds the normal value due to wear or faulty adjustment. This work aims at diagnosing the valve clearance fault based on the vibration signals measured on the engine cylinder heads. The non-stationarity of the ICE operating condition makes it difficult to obtain the nominal baseline, which is always an awkward problem for fault diagnosis. This paper overcomes the problem by inspecting the timing of valve closing impacts, of which the referenced baseline can be obtained by referencing design parameters rather than extraction during healthy conditions. To accurately detect the timing of valve closing impact from vibration signals, we carry out a new method to detect and extract the commencement of the impacts. The results of experiments conducted on a twelve-cylinder ICE test rig show that the approach is capable of extracting the commencement of valve closing impact accurately and using only one feature can give a superior monitoring of valve clearance. With the help of this technique, the valve clearance fault becomes detectable even without the comparison to the baseline, and the changing trend of the clearance could be trackable.

  18. 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)

  19. Design optimization of dual-axis driving mechanism for satellite antenna with two planar revolute clearance joints

    Science.gov (United States)

    Bai, Zheng Feng; Zhao, Ji Jun; Chen, Jun; Zhao, Yang

    2018-03-01

    In the dynamic analysis of satellite antenna dual-axis driving mechanism, it is usually assumed that the joints are ideal or perfect without clearances. However, in reality, clearances in joints are unavoidable due to assemblage, manufacturing errors and wear. When clearance is introduced to the mechanism, it will lead to poor dynamic performances and undesirable vibrations due to impact forces in clearance joint. In this paper, a design optimization method is presented to reduce the undesirable vibrations of satellite antenna considering clearance joints in dual-axis driving mechanism. The contact force model in clearance joint is established using a nonlinear spring-damper model and the friction effect is considered using a modified Coulomb friction model. Firstly, the effects of clearances on dynamic responses of satellite antenna are investigated. Then the optimization method for dynamic design of the dual-axis driving mechanism with clearance is presented. The objective of the optimization is to minimize the maximum absolute vibration peak of antenna acceleration by reducing the impact forces in clearance joint. The main consideration here is to optimize the contact parameters of the joint elements. The contact stiffness coefficient, damping coefficient and the dynamic friction coefficient for clearance joint elements are taken as the optimization variables. A Generalized Reduced Gradient (GRG) algorithm is used to solve this highly nonlinear optimization problem for dual-axis driving mechanism with clearance joints. The results show that the acceleration peaks of satellite antenna and contact forces in clearance joints are reduced obviously after design optimization, which contributes to a better performance of the satellite antenna. Also, the application and limitation of the proposed optimization method are discussed.

  20. [Conservative calibration of a clearance monitor system for waste material from nuclear medicine].

    Science.gov (United States)

    Wanke, Carsten; Geworski, Lilli

    2014-09-01

    Clearance monitor systems are used for gross gamma measurements of waste potentially contaminated with radioactivity. These measurements are to make sure that legal requirements, e.g. clearance criteria according to the german radiation protection ordinance, are met. This means that measurement results may overestimate, but must not underestimate the true values. This paper describes a pragmatic way using a calibrated Cs-137 point source to generate a conservative calibration for the clearance monitor system used in the Medizinische Hochschule Hannover (MHH). The most important nuclides used in nuclear medicine are considered. The measurement result reliably overestimates the true value of the activity present in the waste. The calibration is compliant with the demands for conservativity and traceability to national standards. Copyright © 2014. Published by Elsevier GmbH.

  1. The Development and Implementation of the Kennedy Space Center Umbilical Clearance Tool

    Science.gov (United States)

    Chesnutt, David

    2016-01-01

    In preparation for NASAs upcoming Space Launch System program, the Kennedy Space Center is currently developing subsystems to provide fuel, purges and communications to the flight vehicle, known as umbilicals. It is vital to the crew and mission that these umbilicals release at T-0 without re-contacting the vehicle as it is accelerating from the launch pad. To help ensure this requirement is met by the program, a methodology of evaluating the moving bodies was developed and implemented into a tool using MATLAB. The tool, known as the KSC Umbilical Clearance Tool, takes a given elevation of interest and an umbilical retract profile within the plane to evaluate the clearance between the umbilical arm and thousands of independent flight vehicle drift profiles from a Monte Carlo analysis. The presentation will delve into the challenges associated with developing and implementing the tool framed in the context of evaluating the clearance for one of the SLS umbilicals.

  2. Optimization Based Clearance of Flight Control Laws A Civil Aircraft Application

    CERN Document Server

    Hansson, Anders; Puyou, Guilhem

    2012-01-01

    This book summarizes the main achievements of the EC funded 6th Framework Program project COFCLUO – Clearance of Flight Control Laws Using Optimization. This project successfully contributed to the achievement of a top-level objective to meet society’s needs for a more efficient, safer and environmentally friendly air transport by providing new techniques and tools for the clearance of flight control laws. This is an important part of the certification and qualification process of an aircraft – a costly and time-consuming process for the aeronautical industry.   The overall objective of the COFCLUO project was to develop and apply optimization techniques to the clearance of flight control laws in order to improve efficiency and reliability. In the book, the new techniques are explained and benchmarked against traditional techniques currently used by the industry. The new techniques build on mathematical criteria derived from the certification and qualification requirements together with suitable models...

  3. Robust Optimization Design for Turbine Blade-Tip Radial Running Clearance using Hierarchically Response Surface Method

    Science.gov (United States)

    Zhiying, Chen; Ping, Zhou

    2017-11-01

    Considering the robust optimization computational precision and efficiency for complex mechanical assembly relationship like turbine blade-tip radial running clearance, a hierarchically response surface robust optimization algorithm is proposed. The distribute collaborative response surface method is used to generate assembly system level approximation model of overall parameters and blade-tip clearance, and then a set samples of design parameters and objective response mean and/or standard deviation is generated by using system approximation model and design of experiment method. Finally, a new response surface approximation model is constructed by using those samples, and this approximation model is used for robust optimization process. The analyses results demonstrate the proposed method can dramatic reduce the computational cost and ensure the computational precision. The presented research offers an effective way for the robust optimization design of turbine blade-tip radial running clearance.

  4. Comparison of two lung clearance models based on the dissolution rates of oxidized depleted uranium

    International Nuclear Information System (INIS)

    Crist, K.C.

    1984-10-01

    An in-vitro dissolution study was conducted on two respirable oxidized depleted uranium samples. The dissolution rates generated from this study were then utilized in the International Commission on Radiological Protection Task Group lung clearance model and a lung clearance model proposed by Cuddihy. Predictions from both models based on the dissolution rates of the amount of oxidized depleted uranium that would be cleared to blood from the pulmonary region following an inhalation exposure were compared. It was found that the predictions made by both models differed considerably. The difference between the predictions was attributed to the differences in the way each model perceives the clearance from the pulmonary region. 33 references, 11 figures, 9 tables

  5. Comparison of two lung clearance models based on the dissolution rates of oxidized depleted uranium

    Energy Technology Data Exchange (ETDEWEB)

    Crist, K.C.

    1984-10-01

    An in-vitro dissolution study was conducted on two respirable oxidized depleted uranium samples. The dissolution rates generated from this study were then utilized in the International Commission on Radiological Protection Task Group lung clearance model and a lung clearance model proposed by Cuddihy. Predictions from both models based on the dissolution rates of the amount of oxidized depleted uranium that would be cleared to blood from the pulmonary region following an inhalation exposure were compared. It was found that the predictions made by both models differed considerably. The difference between the predictions was attributed to the differences in the way each model perceives the clearance from the pulmonary region. 33 references, 11 figures, 9 tables.

  6. U.S. nuclear fuel cycle regulatory issues on exclusion, exemption, and clearance

    International Nuclear Information System (INIS)

    Meck, R.A.

    1997-01-01

    The U.S. Nuclear Regulatory Commission is considering the use of exclusion and clearance in connection with the nuclear fuel cycle regulations. Clearance of licensed lands, buildings, structures, materials, and equipment could expose members of the public to radiation in addition to background. Establishing and implementing dose criteria for allowed concentrations of radioactivity in the various media raise challenging issues for the regulator. Clearance also raises significant regulatory issues, and these issues reflect trade-offs between concerns for protecting public health and safety, as well as other socioeconomic values and concerns. At the heart of the issues are the adequacy of risk analyses, acceptability of risks, underlying rationales, feasibility and cost of implementation, and exposures of the public to man-made radiation in relation to natural sources of radiation. (author)

  7. Effect of tip clearance on wall shear stress of an axial LVAD

    Science.gov (United States)

    Sarath, S.; Vikas, R.

    2017-09-01

    Wall shear stress is a crucial parameter used for blood damage analysis, and typically a value of 400 Pa is set as a limit. Tip clearance is a major factor contributing to hemolysis and pump efficiency. In this study, different tip gap configurations are used to analyse the wall shear stress developed on the blade surface of a constant thickness blade design, and a varying thickness blade design using CFD analysis. It was found that, for a particular geometry, as the clearance gap reduces, flow rate over the high wall shear stress area decreases even though the high wall shear stress span is found to extend. For each design, the optimum clearance gap is iteratively attained, keeping the maximum WSS as a limiting factor. Thus a better pump designs is obtained, whose leakage flow patterns are lower than that of the initial design, hence also leading to higher pump efficiency.

  8. Factors associated with early mycological clearance in HIV-associated cryptococcal meningitis.

    Science.gov (United States)

    Concha-Velasco, Fátima; González-Lagos, Elsa; Seas, Carlos; Bustamante, Beatriz

    2017-01-01

    The first-line combination therapy for HIV-associated cryptococcal meningitis (CM), a condition of high mortality particularly in the first two weeks of treatment, consists of amphotericin B plus flucytosine (5-FC). Given that 5-FC remains unavailable in many countries, the knowledge of factors influencing mycological clearance in patients treated with second-line therapy could contribute to effective management. To determine the factors associated with the clearance of Cryptococcus sp. from the cerebrospinal fluid by the second week of effective antifungal therapy (early mycological clearance) in HIV-associated CM. Retrospective cohort study based on secondary data corresponding to HIV-associated CM cases hospitalized at a tertiary health care center in Lima, Peru where 5-FC remains unavailable. Risk factors associated with early mycological clearance were analyzed by generalized linear regression models. From January 2000 to December 2013, 234 individuals were discharged with a diagnosis of HIV-associated CM; in 215 we retrieved the required data. The inpatient mortality was 20% (43/215), 15 of them in the first two weeks of treatment. In the final model (157 cases), adjusted for age, previous episode of CM, ART use, type of antifungal treatment, raised intracranial pressure, frequency of therapeutic lumbar punctures, baseline fungal burden and treatment period, the factors associated with early mycological clearance were: Amphotericin B deoxycholate plus fluconazole as combination therapy (RR, 1.56; 95% CI, 1.14-2.14); severe baseline intracranial pressure (≥35 cm H2O) (RR, 0.57; 95% CI, 0.33-0.99); and baseline fungal burden over 4.5 log10 CFU/mL (RR, 0.61 95% CI: 0.39-0.95). In a setting without access to first-line therapy for CM, the combination therapy with amphotericin B deoxycholate plus fluconazole was positively associated with early mycological clearance, while high fungal burden and severe baseline intracranial pressure were negatively associated

  9. Immune modulation with sulfasalazine attenuates immunopathogenesis but enhances macrophage-mediated fungal clearance during Pneumocystis pneumonia.

    Directory of Open Access Journals (Sweden)

    Jing Wang

    2010-08-01

    Full Text Available Although T cells are critical for host defense against respiratory fungal infections, they also contribute to the immunopathogenesis of Pneumocystis pneumonia (PcP. However, the precise downstream effector mechanisms by which T cells mediate these diverse processes are undefined. In the current study the effects of immune modulation with sulfasalazine were evaluated in a mouse model of PcP-related Immune Reconstitution Inflammatory Syndrome (PcP-IRIS. Recovery of T cell-mediated immunity in Pneumocystis-infected immunodeficient mice restored host defense, but also initiated the marked pulmonary inflammation and severe pulmonary function deficits characteristic of IRIS. Sulfasalazine produced a profound attenuation of IRIS, with the unexpected consequence of accelerated fungal clearance. To determine whether macrophage phagocytosis is an effector mechanism of T cell-mediated Pneumocystis clearance and whether sulfasalazine enhances clearance by altering alveolar macrophage phagocytic activity, a novel multispectral imaging flow cytometer-based method was developed to quantify the phagocytosis of Pneumocystis in vivo. Following immune reconstitution, alveolar macrophages from PcP-IRIS mice exhibited a dramatic increase in their ability to actively phagocytose Pneumocystis. Increased phagocytosis correlated temporally with fungal clearance, and required the presence of CD4(+ T cells. Sulfasalazine accelerated the onset of the CD4(+ T cell-dependent alveolar macrophage phagocytic response in PcP-IRIS mice, resulting in enhanced fungal clearance. Furthermore, sulfasalazine promoted a TH2-polarized cytokine environment in the lung, and sulfasalazine-enhanced phagocytosis of Pneumocystis was associated with an alternatively activated alveolar macrophage phenotype. These results provide evidence that macrophage phagocytosis is an important in vivo effector mechanism for T cell-mediated Pneumocystis clearance, and that macrophage phenotype can be altered

  10. Estimation of technetium 99m mercaptoacetyltriglycine plasma clearance by use of one single plasma sample

    International Nuclear Information System (INIS)

    Mueller-Suur, R.; Magnusson, G.; Karolinska Inst., Stockholm; Bois-Svensson, I.; Jansson, B.

    1991-01-01

    Recent studies have shown that technetium 99m mercaptoacetyltriglycine (MAG-3) is a suitable replacement for iodine 131 or 123 hippurate in gamma-camera renography. Also, the determination of its clearance is of value, since it correlates well with that of hippurate and thus may be an indirect measure of renal plasma flow. In order to simplify the clearance method we developed formulas for the estimation of plasma clearance of MAG-3 based on a single plasma sample and compared them with the multiple sample method based on 7 plasma samples. The correlation to effective renal plasma flow (ERPF) (according to Tauxe's method, using iodine 123 hippurate), which ranged from 75 to 654 ml/min per 1.73 m 2 , was determined in these patients. Using the developed regression equations the error of estimate for the simplified clearance method was acceptably low (18-14 ml/min), when the single plasma sample was taken 44-64 min post-injection. Formulas for different sampling times at 44, 48, 52, 56, 60 and 64 min are given, and we recommend 60 min as optimal, with an error of estimate of 15.5 ml/min. The correlation between the MAG-3 clearances and ERPF was high (r=0.90). Since normal values for MAG-3 clearance are not yet available, transformation to estimated ERPF values by the regression equation (ERPF=1.86xC MAG-3 +4.6) could be of clinical value in order to compare it with the normal values for ERPF given in the literature. (orig.)

  11. Effects of Karenia brevis on clearance rates and bioaccumulation of brevetoxins in benthic suspension feeding invertebrates.

    Science.gov (United States)

    Echevarria, Michael; Naar, Jerome P; Tomas, Carmelo; Pawlik, Joseph R

    2012-01-15

    Blooms of the toxic alga Karenia brevis occur along coastlines where sessile suspension feeding invertebrates are common components of benthic communities. We studied the effects of K. brevis on four benthic suspension feeding invertebrates common to the coast of the SE United States: the sponge Haliclona tubifera, the bryozoan Bugula neritina, the bivalve Mercenaria mercenaria, and the tunicate Styela plicata. In controlled laboratory experiments, we determined the rate at which K. brevis was cleared from the seawater by these invertebrates, the effect of K. brevis on clearance rates of a non-toxic phytoplankton species, Rhodomonas sp., and the extent to which brevetoxins bioaccumulated in tissues of invertebrates using an enzyme-linked immunosorbent assay (ELISA). All four invertebrate species cleared significant quantities of K. brevis from seawater, with mean clearance rates ranging from 2.27 to 6.71 L g h⁻¹ for H. tubifera and S. plicata, respectively. In the presence of K. brevis, clearance rates of Rhodomonas sp. by B. neritina and S. plicata were depressed by 75% and 69%, respectively, while clearance rates by H. tubifera and M. mercenaria were unaffected. Negative effects of K. brevis were impermanent; after a recovery period of 13 h, B. neritina and S. plicata regained normal clearance rates. All four invertebrates accumulated high concentrations of brevetoxin after a 4h exposure to K. brevis, but when animals were transferred to filtered seawater for 15 h after exposure, brevetoxin concentrations in the tissues of H. tubifera and B. neritina decreased by ∼80%, while there was no change in toxin concentration in the tissues of S. plicata and M. mercenaria. High cell concentrations of K. brevis may cause a suppression of clearance rates in benthic suspension feeding invertebrates, resulting in a positive feedback for bloom formation. Also, high concentrations of toxin may accumulate in the tissues of benthic suspension feeding invertebrates that may

  12. Biomechanical factors behind toe clearance during the swing phase in hemiparetic patients.

    Science.gov (United States)

    Matsuda, Fumihiro; Mukaino, Masahiko; Ohtsuka, Kei; Tanikawa, Hiroki; Tsuchiyama, Kazuhiro; Teranishi, Toshio; Kanada, Yoshikiyo; Kagaya, Hitoshi; Saitoh, Eiichi

    2017-04-01

    The toe clearance of a paretic limb in the swing phase of gait is related to tripping, which is considered a major cause of falls. The biomechanical factors for obtaining toe clearance are more complicated in hemiparetic gait than that in normal gait because of the compensatory movements during swing phase. Understanding the biomechanical factors should help in targeting the point for rehabilitative interventions. To clarify the biomechanical factors behind toe clearance during swing phase in hemiparetic gait. Fifty patients with hemiparesis after a stroke participated in this study. Three-dimensional motion analysis was used for the kinematic analysis of the hemiparetic gait. The correlation coefficients between limb shortening and angle changes and between limb shortening and hip elevation and foot lateral shift were calculated. Limb shortening was defined as the shortening of the hip-toe distance. The significant factors that determine toe clearance were examined by multiple regression analysis. Independent variables were limb shortening, hip elevation, and foot lateral shift. Limb shortening was negatively correlated with hip elevation (r = -0.75) and foot lateral shift (r = -0.41). Multiple regression analysis showed a significant contribution of limb shortening and hip elevation to toe clearance. The coefficient of determination was 0.95. Toe clearance was mainly determined by limb shortening and hip elevation, which were found to be in a trade-off relationship. These results warrant further investigation into the use of three-dimensional motion analysis in the rehabilitation clinic to facilitate targeted rehabilitative training to restore gait ability.

  13. Changes in glomerular filtration rate, lithium clearance and plasma protein clearances in the early phase after unilateral nephrectomy in living healthy renal transplant donors

    DEFF Research Database (Denmark)

    Strandgaard, S; Kamper, A; Skaarup, P

    1988-01-01

    1. Glomerular and tubular function was studied before and 2 months after unilateral nephrectomy in 14 healthy kidney donors by measurement of the clearances of 51Cr-labelled ethylenediaminetetra-acetate, lithium, beta 2-microglobulin, albumin and immunoglobulin G. 2. The glomerular filtration rate...... APR and a fall in FPR. The proximal tubules thus initially handle the increased filtrate load by passing it on to more distal nephron segments.(ABSTRACT TRUNCATED AT 250 WORDS)...

  14. 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

  15. Clearance Rate of the Mussel Anodonta Californiensis Exposed to Nannochloropsis Algae

    Science.gov (United States)

    Castañeda, G. R.; Luthy, R. G.; Ismail, N.

    2012-12-01

    Bivalves such as mussels and clams are filter feeding organisms that can be utilized to remove particulate matter from water. The native mussel species Anodonta californiensis is being studied for use as a potential natural treatment mechanism to filter water within treatment wetlands. Quantifying the ability of these mussels to remove particulate matter is important information necessary to understand their potential to purify water. Results from clearance rate experiments will be discussed. Information obtained from these clearance rate experiments can potentially be extrapolated to understand the capability of mussels to remove other particulate matter or contaminants.

  16. Relating minimum toe clearance to prospective, self-reported, trip-related stumbles in the community.

    Science.gov (United States)

    Rosenblatt, Noah J; Bauer, Angela; Grabiner, Mark D

    2017-08-01

    Individuals with transtibial amputation are at increase risk of falling. The absence of an ankle joint and the associated musculature in these individuals can reduce clearance between the prosthetic foot and ground during the swing phase of gait, which may increase the risk of stumbling and in turn falling. To associate minimum toe clearance during gait in the laboratory with community-based, trip-related stumbles by individuals with transtibial amputation using conventional feet. Prospective cohort design; following quantitative gait analysis, participants completed electronic surveys to prospectively report stumbles and falls for 1 year thereafter. General community with gait analysis conducted within a motion analysis laboratory and prospective tracking of stumbles occurring in the community. A volunteer sample of eight unilateral, transtibial amputees that were K3 or K4 level ambulators and current patients at a local prosthetic clinic. All participants completed the entire 1-year follow-up study. Prosthetic-side minimum toe clearance while walking on a level treadmill at self-selected speed and self-reported trip-related stumbles in the community. Minimum toe clearance was defined as a local minimum of the vertical displacement of the toe from toe-off to heelstrike relative to its position during midstance. Prosthetic-side minimum toe clearance was more than 50% lower for participants who reported one or more trip-related stumbles on that side compared with participants who reported zero trip-related stumbles on the prosthetic side (minimum toe clearance = 12.3 ± 0.8 mm vs 25.6 ± 5.4 mm, respectively; p = 0.036). This is the first study relating laboratory-based measures to prospective stumbles by prosthesis users. The results suggest that prosthesis users with low minimum toe clearance may be at increased risk of experiencing a trip-related stumble in the community. Given that frequent stumbling increases the risk of falling, future work

  17. Colloid clearance rate changes in children with homozygous-β-thalassemia in relation to blood transfusion

    International Nuclear Information System (INIS)

    Dimitriou, P.A.; Karpathios, T.E.; Antipas, S.E.; Fretzayias, A.M.; Kasfiki, A.G.; Melissinos, K.G.; Matsaniotis, N.S.

    1980-01-01

    The plasma clearance rate of heat denatured human serum albumin (DHAI-125, 5 mg/kg body weight) was studied in 20 children with homozygous-β-thalassemia before and 7-10 days after blood transfusion. A significant increase of the DHAI-125 clearance rate (P < 0.02) was found 7-10 days after blood transfusion while the spleen presented its minimum size. This finding may be relevant to the improved intrasplenic blood circulation after blood transfusion due to the release of the blood trapped within the spleen. (orig.)

  18. A proposal for identifying the low renal uric acid clearance phenotype.

    Science.gov (United States)

    Indraratna, Praveen L; Stocker, Sophie L; Williams, Kenneth M; Graham, Garry G; Jones, Graham; Day, Richard O

    2010-01-01

    Investigation of the genetic basis of hyperuricaemia is a subject of intense interest. However, clinical studies commonly include hyperuricaemic patients without distinguishing between 'over-producers' or 'under-excretors' of urate. The statistical power of studies of genetic polymorphisms of genes encoding renal urate transporters is diluted if 'over-producers' of uric acid are included. We propose that lower than normal fractional renal clearance of urate is a better inclusion criterion for these studies. We also propose that a single daytime spot urine sample for calculation of fractional renal clearance of urate should be preferred to calculation from 24-hour urine collections.

  19. 51Cr-EDTA plasma clearance in severe renal failure determined by one plasma sample

    DEFF Research Database (Denmark)

    Kamper, A L; Nielsen, S L

    1989-01-01

    Two hundred and thirty-four measurements of standard 51Cr-EDTA plasma clearance were made in 50 patients with severe chronic renal failure. Based on these data two calculation methods were attempted using one plasma sample drawn 24 h after injection of 51Cr-EDTA. One of the methods used the 'one...... renal dysfunction (estimated clearance values below 21 ml/min) may be determined with adequate precision by one plasma sample drawn at 24 h after injection of the tracer without sampling at 5 h. This appears to be a very practical simplification....

  20. Effect of Albumin on the Biliary Clearance of Compounds in Sandwich-Cultured Rat Hepatocytes

    OpenAIRE

    Wolf, Kristina K.; Brouwer, Kenneth R.; Pollack, Gary M.; Brouwer, Kim L.R.

    2008-01-01

    The purpose of the present study was to evaluate the effects of bovine serum albumin (BSA) and essentially fatty acid-free BSA (BSA-FAF) on the biliary clearance of compounds in sandwich-cultured rat hepatocytes. Unbound fraction (fu), biliary excretion index (BEI), and unbound intrinsic biliary clearance (intrinsic Cl’biliary) were determined for digoxin, pravastatin, and taurocholate in the absence or presence of BSA or BSA-FAF. BSA had little effect on the BEI or intrinsic Cl’biliary of th...

  1. The kidneys play an important role in the clearance of rFVIIa in rats

    DEFF Research Database (Denmark)

    Vestergaard, Bill; Appa, Rupa S.; Lykkesfeldt, Jens

    2014-01-01

    study was to evaluate the importance of the kidneys in the clearance process of rFVIIa after iv administration to rats using a nephrectomy model. MATERIALS AND METHODS: A nephrectomized rat model was established and validated using inulin, a compound primarily cleared by the kidneys, as a test substance...... of mixed effects methods, where a pharmacokinetic model was used to simultaneously model all data from healthy, sham operated, and nephrectomized rats. RESULTS: Nephrectomized animals showed stable rectal temperature, SpO2 and pulse and as expected, clearance of inulin was essentially abolished compared...

  2. How I do it: Simple and effortless approach to identify thoracodorsal nerve on axillary clearance procedure.

    Science.gov (United States)

    Zin, T; Maw, M; Oo, Sm; Pai, Dr; Paijan, Rb; Kyi, M

    2012-01-01

    Breast cancer surgery frequently involves an axillary clearance procedure for nodal metastases. Injury to the thoracodorsal nerve is one of the complications related to the axillary dissection. The thoracodorsal nerve innervates the latissimus dorsi muscle which facilitates in certain movements of the arm. Moreover, it can be used as a nerve graft in long thoracic nerve injury whether in trauma or surgery. Understanding the anatomy structures and good surgical technique in the axillary clearance procedure can identify and prevent such an injury to the thoracodorsal nerve. Here, we demonstrate a simple and effortless technique for identification of the thoracodorsal nerve during axillary surgery.

  3. Robust Foot Clearance Estimation Based on the Integration of Foot-Mounted IMU Acceleration Data.

    Science.gov (United States)

    Benoussaad, Mourad; Sijobert, Benoît; Mombaur, Katja; Coste, Christine Azevedo

    2015-12-23

    This paper introduces a method for the robust estimation of foot clearance during walking, using a single inertial measurement unit (IMU) placed on the subject's foot. The proposed solution is based on double integration and drift cancellation of foot acceleration signals. The method is insensitive to misalignment of IMU axes with respect to foot axes. Details are provided regarding calibration and signal processing procedures. Experimental validation was performed on 10 healthy subjects under three walking conditions: normal, fast and with obstacles. Foot clearance estimation results were compared to measurements from an optical motion capture system. The mean error between them is significantly less than 15 % under the various walking conditions.

  4. 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.)

  5. 21 CFR 884.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... existing or reasonably foreseeable characteristics of commercially distributed devices within that generic...) The modified device operates using a different fundamental scientific technology than a legally... qualitative, or are used to determine immunity, or the assay is intended for use in matrices other than serum...

  6. 21 CFR 874.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... reasonably foreseeable characteristics of commercially distributed devices within that generic type or, in... device operates using a different fundamental scientific technology than a legally marketed device in... immunoglobulin G (IgG) or IgG assays when the results are not qualitative, or are used to determine immunity, or...

  7. 21 CFR 870.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... reasonably foreseeable characteristics of commercially distributed devices within that generic type or, in... device operates using a different fundamental scientific technology than a legally marketed device in... immunoglobulin G (IgG) or IgG assays when the results are not qualitative, or are used to determine immunity, or...

  8. 21 CFR 890.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... reasonably foreseeable characteristics of commercially distributed devices within that generic type or, in... device operates using a different fundamental scientific technology than a legally marketed device in... immunoglobulin G (IgG) or IgG assays when the results are not qualitative, or are used to determine immunity, or...

  9. 21 CFR 866.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... existing or reasonably foreseeable characteristics of commercially distributed devices within that generic...) The modified device operates using a different fundamental scientific technology than a legally... qualitative, or are used to determine immunity, or the assay is intended for use in matrices other than serum...

  10. 21 CFR 862.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... the device has existing or reasonably foreseeable characteristics of commercially distributed devices... professionals only; (b) The modified device operates using a different fundamental scientific technology than a... are not qualitative, or are used to determine immunity, or the assay is intended for use in matrices...

  11. 21 CFR 872.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... reasonably foreseeable characteristics of commercially distributed devices within that generic type or, in... device operates using a different fundamental scientific technology than a legally marketed device in... immunoglobulin G (IgG) or IgG assays when the results are not qualitative, or are used to determine immunity, or...

  12. 21 CFR 864.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... existing or reasonably foreseeable characteristics of commercially distributed devices within that generic...) The modified device operates using a different fundamental scientific technology than a legally... qualitative, or are used to determine immunity, or the assay is intended for use in matrices other than serum...

  13. 21 CFR 878.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... existing or reasonably foreseeable characteristics of commercially distributed devices within that generic...) The modified device operates using a different fundamental scientific technology than a legally... qualitative, or are used to determine immunity, or the assay is intended for use in matrices other than serum...

  14. 21 CFR 888.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... reasonably foreseeable characteristics of commercially distributed devices within that generic type or, in... device operates using a different fundamental scientific technology than a legally marketed device in... immunoglobulin G (IgG) or IgG assays when the results are not qualitative, or are used to determine immunity, or...

  15. 21 CFR 892.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... reasonably foreseeable characteristics of commercially distributed devices within that generic type or, in... device operates using a different fundamental scientific technology than a legally marketed device in... immunoglobulin G (IgG) or IgG assays when the results are not qualitative, or are used to determine immunity, or...

  16. 21 CFR 882.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... reasonably foreseeable characteristics of commercially distributed devices within that generic type or, in... device operates using a different fundamental scientific technology than a legally marketed device in... immunoglobulin G (IgG) or IgG assays when the results are not qualitative, or are used to determine immunity, or...

  17. 21 CFR 880.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... device has existing or reasonably foreseeable characteristics of commercially distributed devices within...) The modified device operates using a different fundamental scientific technology than a legally... qualitative, or are used to determine immunity, or the assay is intended for use in matrices other than serum...

  18. 21 CFR 868.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... reasonably foreseeable characteristics of commercially distributed devices within that generic type or, in... device operates using a different fundamental scientific technology than a legally marketed device in... immunoglobulin G (IgG) or IgG assays when the results are not qualitative, or are used to determine immunity, or...

  19. 21 CFR 876.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... existing or reasonably foreseeable characteristics of commercially distributed devices within that generic...) The modified device operates using a different fundamental scientific technology than a legally... qualitative, or are used to determine immunity, or the assay is intended for use in matrices other than serum...

  20. 21 CFR 886.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... reasonably foreseeable characteristics of commercially distributed devices within that generic type or, in... device operates using a different fundamental scientific technology than a legally marketed device in... immunoglobulin G (IgG) or IgG assays when the results are not qualitative, or are used to determine immunity, or...

  1. Role of calculated glomerular filtration rate using percutaneous nephrostomy creatinine clearance in the era of radionuclide scintigraphy

    Directory of Open Access Journals (Sweden)

    Sunil Raghunath Patil

    2017-01-01

    Conclusions: GFR based on radionuclide scintigraphy may be insufficient for evaluation of residual renal function to determine the management of obstructed kidney with borderline function. For adequate decision-making, other factors including creatinine clearance via PCN should also be considered. Gates method tends to overestimate GFR as compared to calculated creatinine clearance at low GFR levels.

  2. Liver volume, portal vein flow, and clearance of indocyanine green and antipyrine in hyperthyroidism before and after antithyroid treatment

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Sonne, J; Court-Payen, M

    1999-01-01

    The aim of the study was to examine liver volume, portal vein flow, and indocyanine green (ICG) and antipyrine clearance in hyperthyroidism before and after antithyroid drug treatment.......The aim of the study was to examine liver volume, portal vein flow, and indocyanine green (ICG) and antipyrine clearance in hyperthyroidism before and after antithyroid drug treatment....

  3. The clearance concept with special reference to determination of glomerular filtration rate in patients with fluid retention

    DEFF Research Database (Denmark)

    Henriksen, Ulrik L; Henriksen, Jens H

    2014-01-01

    In subjects without fluid retention, the total plasma clearance of a renal filtration indicator (inulin, (99m) Tc-DTPA, (51) Cr-EDTA) is close to the urinary plasma clearance. Conversely, in patients with fluid retention (oedema, pleural effusions, ascites), there is a substantial discrepancy...

  4. 10 CFR 2.905 - Access to restricted data and national security information for parties; security clearances.

    Science.gov (United States)

    2010-01-01

    ... information for parties; security clearances. 2.905 Section 2.905 Energy NUCLEAR REGULATORY COMMISSION RULES... to Adjudicatory Proceedings Involving Restricted Data and/or National Security Information § 2.905 Access to restricted data and national security information for parties; security clearances. (a) Access...

  5. Clearance of yellow pigments lutein and zeathanxin in channel catfish reared at different water temperatures

    Science.gov (United States)

    A study was conducted to determine clearance time of yellow pigments lutein and zeaxanthin in channel catfish at various temperatures. Fish of initial weight of 13.4 g were stocked into flow-through aquaria and fed once daily with a yellow pigment enhanced diet for 11 weeks when the yellow color be...

  6. Experimental and computational investigation of the tip clearance flow in a transonic axial compressor rotor

    Energy Technology Data Exchange (ETDEWEB)

    Suder, K.L. [NASA-Lewis Research Center, Cleveland, OH (United States); Celestina, M.L. [Sverdrup Technology Inc., Cleveland, OH (United States). Lewis Research Center Group

    1996-04-01

    Experimental and computational techniques are used to investigate tip clearance flows in a transonic axial compressor rotor at design and part-speed conditions. Laser anemometer data acquired in the endwall region are presented for operating conditions near peak efficiency and near stall at 100 percent design speed and at near peak efficiency at 60 percent design speed. The role of the passage shock/leakage vortex interaction at design speed, the radial influence of the tip clearance flow extends to 20 times the physical tip clearance height. At part speed, in the absence of the shock, the radial extent is only five times the tip clearance height. Both measurements and analysis indicate that under part-speed operating conditions a second vortex, which does not originate from the tip leakage flow, forms in the end-wall region within the blade passage and exits the passage near midpitch. Mixing of the leakage vortex with the primary flow downstream of the rotor at both design and part-speed conditions is also discussed.

  7. Experimental and Computational Investigation of the Tip Clearance Flow in a Transonic Axial Compressor Rotor

    Science.gov (United States)

    Suder, Kenneth L.; Celestina, Mark L.

    1995-01-01

    Experimental and computational techniques are used to investigate tip clearance flows in a transonic axial compressor rotor at design and part speed conditions. Laser anemometer data acquired in the endwall region are presented for operating conditions near peak efficiency and near stall at 100% design speed and at near peak efficiency at 60% design speed. The role of the passage shock/leakage vortex interaction in generating endwall blockage is discussed. As a result of the shock/vortex interaction at design speed, the radial influence of the tip clearance flow extends to 20 times the physical tip clearance height. At part speed, in the absence of the shock, the radial extent is only 5 times the tip clearance height. Both measurements and analysis indicate that under part-speed operating conditions a second vortex, which does not originate from the tip leakage flow, forms in the endwall region within the blade passage and exits the passage near midpitch. Mixing of the leakage vortex with primary flow downstream of the rotor at both design and part speed conditions is also discussed.

  8. Effect of raised thoracic pressure and volume on 99mTc-DTPA clearance in humans

    Energy Technology Data Exchange (ETDEWEB)

    Nolop, K.B.; Maxwell, D.L.; Royston, D.; Hughes, J.M.

    1986-05-01

    Although positive airway pressure is often used to treat acute pulmonary edema, the effects on epithelial solute flux are not well known. We measured independently the effect of 1) positive pressure and 2) voluntary hyperinflation on the clearance of inhaled technetium-99m-labeled diethylenetriaminepentaacetic acid (/sup 99m/Tc-DTPA) in six nonsmokers and six smokers. Lung volumes were monitored by inductance plethysmography. Each subject was studied in four situations: 1) low end-expiratory volume (LO-), 2) low volume plus 9 cmH2O continuous positive airway pressure (LO+), 3) high end-expiratory volume (HI-), and 4) high volume plus continuous positive airway pressure (HI+). The clearance half time of 99mTc-DTPA for the nonsmokers decreased from 64.8 +/- 7.0 min (mean +/- SE) at LO- to 23.2 +/- 5.3 min at HI- (P less than 0.05). Positive pressure had no synergistic effect. The mean clearance half time for the smokers was faster than nonsmokers at base line but unaffected by similar changes in thoracic volume and pressure. We conclude that, in nonsmokers, positive airway pressure increases /sup 99m/Tc-DTPA clearance primarily through an increase in lung volume and that smokers are immune to these effects.

  9. Measurement of glomerular filtration rate in adults: accuracy of five single-sample plasma clearance methods

    DEFF Research Database (Denmark)

    Rehling, M; Rabøl, A

    1989-01-01

    After an intravenous injection of a tracer that is removed from the body solely by filtration in the kidneys, the glomerular filtration rate (GFR) can be determined from its plasma clearance. The method requires a great number of blood samples but collection of urine is not needed. In the present...

  10. 78 FR 48076 - Facility Security Clearance and Safeguarding of National Security Information and Restricted Data

    Science.gov (United States)

    2013-08-07

    ... required security education training for employees of NRC licensees possessing security clearances so that... and methods for providing this training. This action would establish uniformity in the frequency of... education. All cleared employees must be provided with security training and briefings commensurate with...

  11. 78 FR 5858 - Agency Information Collection Activities: Requests for Comments; Clearance of Renewed Approval of...

    Science.gov (United States)

    2013-01-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Agency Information Collection Activities: Requests for Comments; Clearance... assure the foreign air carrier's ability to navigate and communicate safely within the U.S. National...

  12. Self-clearance of Pestivirus in a Pyrenean Chamois ( Rupicapra pyrenaica) Population.

    Science.gov (United States)

    Gilot-Fromont, Emmanuelle; Garel, Mathieu; Gibert, Philippe; Lambert, Sébastien; Menaut, Pierre; Bonetti, Brigitte; Game, Yvette; Reynaud, Gaël; Foulché, Kévin

    2018-04-01

      Understanding the dynamics of host-pathogen interaction is key to the management of epidemics. A pestivirus belonging to the border disease virus group 4 emerged around 2001 in Pyrenean chamois ( Rupicapra pyrenaica) in Spain and France. The virus had significant demographic impact in some populations, but it was less harmful and more endemic in other places. The determinants of these local variations are still unclear. Here, we documented empirical evidence of self-clearance of the virus in a chamois population in France. This population has regularly been counted, and chamois were trapped and harvested each year, providing unique demographic and epidemiologic surveys of the population since 1984 and 1994, respectively. The virus was detected using direct (PCR) and indirect (antibody) testing. We showed that virus transmission declined in 2011-12 and likely ceased in 2013, leading to a decline in antibody prevalence since 2014. Self-clearance may be due to limited exchanges with other populations, decrease in population size after an epizootic, and herd immunity. The age structure of captured animals shifted to younger age classes after virus self-clearance, suggesting a return to a colonizing population structure. The possible consequences of virus re-entry are discussed. This observation suggests that pestivirus dynamics occurs at the scale of the metapopulation of Pyrenean chamois. Local self-clearance and re-emergence may help explain the variation of virus dynamics at the local scale.

  13. 76 FR 61132 - Privacy Act; System of Records: State-77, Country Clearance Records

    Science.gov (United States)

    2011-10-03

    .... Department of State. STATE-77 SYSTEM NAME: Country Clearance Records. SECURITY CLASSIFICATION: Unclassified. SYSTEM LOCATION: Office of Management Policy, Rightsizing and Innovation (M/PRI), Department of State... MANAGER AND ADDRESS: Director, Office of Management Policy, Rightsizing and Innovation (M/PRI), 2201 C...

  14. 76 FR 63680 - Public Roundtable on Execution, Clearance and Settlement of Microcap Securities

    Science.gov (United States)

    2011-10-13

    ... Doc No: 2011-26440] SECURITIES AND EXCHANGE COMMISSION [Release No. 34-65511; File No. 4-639] Public Roundtable on Execution, Clearance and Settlement of Microcap Securities AGENCY: Securities and Exchange..., 2011, commencing at 1 p.m. and ending at 5 p.m., staff of the Securities and Exchange Commission (``SEC...

  15. Optimal sampling strategies to assess inulin clearance in children by the inulin single-injection method

    NARCIS (Netherlands)

    van Rossum, Lyonne K.; Mathot, Ron A. A.; Cransberg, Karlien; Vulto, Arnold G.

    2003-01-01

    Glomerular filtration rate in patients can be determined by estimating the plasma clearance of inulin with the single-injection method. In this method, a single bolus injection of inulin is administered and several blood samples are collected. For practical and convenient application of this method

  16. Glucose clearance in aged trained skeletal muscle during maximal insulin with superimposed exercise

    DEFF Research Database (Denmark)

    Dela, Flemming; Mikines, K J; Larsen, J J

    1999-01-01

    Insulin and muscle contractions are major stimuli for glucose uptake in skeletal muscle and have in young healthy people been shown to be additive. We studied the effect of superimposed exercise during a maximal insulin stimulus on glucose uptake and clearance in trained (T) (1-legged bicycle tra...

  17. [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.

  18. Degradability and Clearance of Silicon, Organosilica, Silsesquioxane, Silica Mixed Oxide, and Mesoporous Silica Nanoparticles

    KAUST Repository

    Croissant, Jonas G.

    2017-01-13

    The biorelated degradability and clearance of siliceous nanomaterials have been questioned worldwide, since they are crucial prerequisites for the successful translation in clinics. Typically, the degradability and biocompatibility of mesoporous silica nanoparticles (MSNs) have been an ongoing discussion in research circles. The reason for such a concern is that approved pharmaceutical products must not accumulate in the human body, to prevent severe and unpredictable side-effects. Here, the biorelated degradability and clearance of silicon and silica nanoparticles (NPs) are comprehensively summarized. The influence of the size, morphology, surface area, pore size, and surface functional groups, to name a few, on the degradability of silicon and silica NPs is described. The noncovalent organic doping of silica and the covalent incorporation of either hydrolytically stable or redox- and enzymatically cleavable silsesquioxanes is then described for organosilica, bridged silsesquioxane (BS), and periodic mesoporous organosilica (PMO) NPs. Inorganically doped silica particles such as calcium-, iron-, manganese-, and zirconium-doped NPs, also have radically different hydrolytic stabilities. To conclude, the degradability and clearance timelines of various siliceous nanomaterials are compared and it is highlighted that researchers can select a specific nanomaterial in this large family according to the targeted applications and the required clearance kinetics.

  19. Antipyrine, oxazepam, and indocyanine green clearance in patients with chronic pancreatitis and healthy subjects

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Sonne, J; Larsen, S

    1999-01-01

    Hepatic drug metabolism was examined in patients with chronic pancreatitis and healthy controls by using a cocktail design with three different model compounds: antipyrine to express phase-I oxidation, oxazepam to express phase-II conjugation, and indocyanine green (ICG), a high-clearance compound....

  20. Association between swallow perception and esophageal bolus clearance in patients with globus sensation.

    Science.gov (United States)

    Chen, Chien-Lin; Yi, Chih-Hsun; Liu, Tso-Tsai

    2013-04-01

    Globus sensation is common, but its pathogenesis is not yet clear. Our purpose was to investigate subjective perception of swallowing and esophageal motility by combined multichannel intraluminal impedance and manometry (MII-EM) for patients with globus sensation. Combined MII-EM was performed for 25 globus patients and 15 healthy controls. Swallows were abnormal if hypocontractivity or simultaneous contractions occurred. Esophageal bolus transit was incomplete if bolus exit was not found at one or more of all measurement sites. Perception of each swallow was assessed by use of a standardized scoring system, and was enhanced if the score was >1. Few globus patients reported enhanced perception during viscous or solid swallows. Incomplete bolus transit and enhanced perception occurred similarly between viscous and solid boluses. Agreement between enhanced perception and proximal bolus clearance was greater during solid swallows (κ = 0.45, 95 % CI: 0.32-0.58) than during viscous swallows (κ = 0.13, 95 % CI: 0-0.25) (P perception and total bolus clearance was greater during solid swallows (κ = 0.46, 95 % CI: 0.34-0.58) than during viscous swallows (κ = 0.11, 95 % CI: 0-0.22) (P perception is uncommon in patients with globus sensation, although there is a significant association between enhanced esophageal perception and solid bolus clearance. Application of a solid bolus may help better delineation of the interrelationship between the subjective perception of bolus passage and the objective measurement of bolus clearance.

  1. The detailed measurement of foot clearance by young adults during stair descent.

    Science.gov (United States)

    Telonio, A; Blanchet, S; Maganaris, C N; Baltzopoulos, V; McFadyen, B J

    2013-04-26

    Foot clearance is an important variable for understanding safe stair negotiation, but few studies have provided detailed measures of it. This paper presents a new method to calculate minimal shoe clearance during stair descent and compares it to previous literature. Seventeen healthy young subjects descended a five step staircase with step treads of 300 mm and step heights of 188 mm. Kinematic data were collected with an Optotrak system (model 3020) and three non-colinear infrared markers on the feet. Ninety points were digitized on the foot sole prior to data collection using a 6 marker probe and related to the triad of markers on the foot. The foot sole was reconstructed using the Matlab (version 7.0) "meshgrid" function and minimal distance to each step edge was calculated for the heel, toe and foot sole. Results showed significant differences in minimum clearance between sole, heel and toe, with the shoe sole being the closest and the toe the furthest. While the hind foot sole was closest for 69% of the time, the actual minimum clearance point on the sole did vary across subjects and staircase steps. This new method, and the findings on healthy young subjects, can be applied to future studies of other populations and staircase dimensions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Impact of Lower Pole Anatomy on Stone Clearance After Shock Wave Lithotripsy

    Directory of Open Access Journals (Sweden)

    Yung-Shun Juan

    2005-08-01

    Full Text Available This study retrospectively analyzed patients treated with shock wave ithotripsy (SWL for lower calyceal stones, to determine the influence of the lower pole anatomy and stone size in predicting the clearance of fragments. Between June 2000 and March 2002, we reviewed excretory urography (IVU of 59 patients with isolated lower pole stones treated with SWL. A total of 44 men and 15 women, with an age ranging between 23 and 78 years (mean, 55 years, were included in the study. The patients were divided into two groups, either a stone-free group or residual-stone group. After SWL, overall stone rate was 57.6%, and clearance for stones less than 10 mm in diameter was 64.5%, whereas clearance was 50% for stones between 10 and 20 mm in diameter. Intrarenal anatomy on IVU, such as infundibular width and infundibulopelvi-ureteric angle showed no significant difference between the stone-free and residual-stone groups. Our analysis showed that three significant variables were relevant to stone clearance: infundibular length, stone size and stone burden. We conclude that SWL is the best treatment for lower pole kidney stones 10 mm or less in diameter, showing lower complication and acceptable stone-free rates.

  3. Formation, Clearance and Mouthfeel Perception of Oral Coatings Formed by Emulsion-Filled Gels

    NARCIS (Netherlands)

    Camacho, Sara; Liu, Kun; Linden, Van Der Anoek; Stieger, Markus; De Velde, Van Fred

    2015-01-01

    Four emulsion-filled gelatin gels varying in fat content (5 and 15%) and type of emulsifier (whey protein isolate: fat droplets bound to matrix; Tween 20: fat droplets unbound to matrix) were studied. We investigated (1) the formation and clearance dynamics of fat deposition on the tongue using in

  4. Impact of IL28B polymorphism on treatment induced viral clearance ...

    African Journals Online (AJOL)

    Impact of IL28B polymorphism on treatment induced viral clearance in HCV infected Egyptian patients. ... All patients were treated with PEG-IFN-α/ribavirin; and they were classified according to their response to treatment. Genotyping of IL28B rs12979860 was performed on peripheral blood DNA using polymerase chain ...

  5. Slow late myocardial clearance of thallium: a characteristic phenomenon in coronary artery disease

    International Nuclear Information System (INIS)

    Sklar, J.; Kirch, D.; Johnson, T.; Hasegawa, B.; Peck, S.; Steele, P.

    1982-01-01

    Researchers extended the quantitative seven-pinhole method to follow the dynamics of thallium redistribution after exercise. Researchers observed a pattern of slow late thallium clearance that appears to be characteristic of myocardium supplied by obstructed coronary arteries. In 28 subjects, quantitative thallium scintigrams and blood samples for thallium concentration were taken immediately, 2 hours and 4 hours after maximal treadmill exercise. Twenty subjects had coronary artery disease (CAD) and eight were normal. The rate of thallium clearance from the blood (TCB) was compared with the rate of thallium clearance from each segmental region of myocardium between the 2- and 4-hour images. In seven of the eight normal subjects, TCM exceeded TCB in all regions of all images. Seventeen of the 20 CAD patients had at least one region where TCM was less than TCB. Of the 13 patients with multivessel CAD 11 had multiple regions with TCM less than TCB. Using this criterion, we detected 31 of 39 obstructed coronary arteries. Of the 37 regions that were abnormal by this analysis, 30 corresponded to obstructed coronary arteries. In contrast, while conventional circumferential count profile analysis also was abnormal in 17 of the 20 CAD patients, it diagnosed multivessel CAD in only five of the 13 patients that had it. These results show that slow late thallium clearance from myocardium is characteristic of regions of myocardium supplied by diseased coronary arteries and that observation of this phenomenon may improve diagnostic sensitivity for the presence of multivessel CAD

  6. Servo-control of water and sodium homeostasis during renal clearance measurements in conscious rats

    DEFF Research Database (Denmark)

    Thomsen, Klaus; Shirley, David G

    2007-01-01

    Servo-controlled fluid and sodium replacement during clearance studies is used in order to prevent loss of body fluid and sodium following diuretic/natriuretic procedures. However, even under control conditions, the use of this technique is sometimes associated with increases in proximal tubular...

  7. A new Kupffer cell receptor mediating plasma clearance of carcinoembryonic antigen by the rat.

    Science.gov (United States)

    Toth, C A; Thomas, P; Broitman, S A; Zamcheck, N

    1982-01-01

    Native human carcinoembryonic antigen is rapidly removed from the circulation by the rat liver Kupffer cell after intravenous injection. The molecule is subsequently transferred to the hepatocyte in an immunologically identifiable form. Carcinoembryonic antigen has a circulatory half-life of 3.7 (+/- 0.8) min, and cellular entry is by receptor-mediated endocytosis. Non-specific fluid pinocytosis and phagocytosis can be excluded as possible mechanisms by the kinetics of clearance and failure of colloidal carbon to inhibit uptake. Substances with known affinity for the hepatic receptors for mannose, N-acetylglucosamine, fucose and galactose all fail to inhibit carcinoembryonic antigen clearance. After two cycles of the Smith degradation, carcinoembryonic antigen is still able to inhibit clearance of the native molecule. Receptor specificity is apparently not dependent on those non-reducing terminal sugars of the native molecule. Performic acid-oxidized carcinoembryonic antigen also inhibits clearance of carcinoembryonic antigen in vivo. Receptor binding is not dependent on tertiary protein conformation. Non-specific cross-reacting antigen, a glycoprotein structurally similar to carcinoembryonic antigen, is cleared by the same mechanism. PMID:6896821

  8. Foot clearance strategy for step-over-step stair climbing in transfemoral amputees.

    Science.gov (United States)

    Hobara, Hiroaki; Kobayashi, Yoshiyuki; Nakamura, Takashi; Yamasaki, Nobuya; Ogata, Toru

    2014-08-01

    Stair ascent is a particularly challenging task for transfemoral amputees. The aim of this clinical note was to describe the kinematic features of foot clearance in transfemoral amputee who can ascend stairs using a step-over-step strategy. The marker trajectories of the first metatarsophalangeal joint (Mt1) and clearance height were measured in two transfemoral amputees who could (TF1) and could not (TF2) climb stairs using a step-over-step strategy. The Mt1 marker trajectories of the TF1 moved backward in the early swing phase, and the trajectory followed an off-centered parabolic arc to achieve a similar clearance height as able-bodied subjects. TF2 could not climb the stairs without tripping in each step. An effective compensatory strategy to avoid tripping during stair climbing may be to use the hip joint for a backward extension and rapid flexion of the prosthetic leg during the early swing phase. The foot clearance strategy in transfemoral amputees who can climb stairs using a step-over-step strategy will help us better understand adaptive prosthetic control and thus develop more effective gait rehabilitation programs. © The International Society for Prosthetics and Orthotics 2013.

  9. Implementation of an Interorganizational System: The Case of Medical Insurance E-Clearance

    Science.gov (United States)

    Bose, Indranil; Liu, Han; Ye, Alex

    2012-01-01

    The patients receiving treatment from a hospital need to interact with multiple entities when claiming reimbursements. The complexities of the medical service supply chain can be simplified with an electronic clearance management system that allows hospitals, medical insurance bureau, bank, and patients to interact in a seamless and cashless…

  10. Improving nuclear envelope dynamics by EBV BFRF1 facilitates intranuclear component clearance through autophagy.

    Science.gov (United States)

    Liu, Guan-Ting; Kung, Hsiu-Ni; Chen, Chung-Kuan; Huang, Cheng; Wang, Yung-Li; Yu, Cheng-Pu; Lee, Chung-Pei

    2018-02-26

    Although a vesicular nucleocytoplasmic transport system is believed to exist in eukaryotic cells, the features of this pathway are mostly unknown. Here, we report that the BFRF1 protein of the Epstein-Barr virus improves vesicular transport of nuclear envelope (NE) to facilitate the translocation and clearance of nuclear components. BFRF1 expression induces vesicles that selectively transport nuclear components to the cytoplasm. With the use of aggregation-prone proteins as tools, we found that aggregated nuclear proteins are dispersed when these BFRF1-induced vesicles are formed. BFRF1-containing vesicles engulf the NE-associated aggregates, exit through from the NE, and putatively fuse with autophagic vacuoles. Chemical treatment and genetic ablation of autophagy-related factors indicate that autophagosome formation and autophagy-linked FYVE protein-mediated autophagic proteolysis are involved in this selective clearance of nuclear proteins. Remarkably, vesicular transport, elicited by BFRF1, also attenuated nuclear aggregates accumulated in neuroblastoma cells. Accordingly, induction of NE-derived vesicles by BFRF1 facilitates nuclear protein translocation and clearance, suggesting that autophagy-coupled transport of nucleus-derived vesicles can be elicited for nuclear component catabolism in mammalian cells.-Liu, G.-T., Kung, H.-N., Chen, C.-K., Huang, C., Wang, Y.-L., Yu, C.-P., Lee, C.-P. Improving nuclear envelope dynamics by EBV BFRF1 facilitates intranuclear component clearance through autophagy.

  11. Site of deposition and factors affecting clearance of aerosolized solute from canine lungs

    International Nuclear Information System (INIS)

    Rizk, N.W.; Luce, J.M.; Hoeffel, J.M.; Price, D.C.; Murray, J.F.

    1984-01-01

    The influence of several factors on lung solute clearance using aerosolized /sup 99m/Tc-diethylenetriaminepentaacetate was determined. The authors used a jet nebulizer-plate separator-balloon system to generate particles with an activity median aerodynamic diameter of 1.1 μm, administered the aerosol in a standard fashion, and determined clearance half times (t/sub 1/2/) with a gamma-scintillation camera. The following serial studies were performed in five anesthetized, paralyzed, intubated, mechanically ventilated dogs: (1) control, with ventilatory frequency (f) = 15 breaths/min and tidal volume (V/sub T/) = 15 ml/kg during solute clearance; (2) repeat control, for reproducibility; (3) increased frequency, with f = 25 breaths/min and V/sub T/ = 10 ml/kg; (4) positive end-expiratory pressure (PEEP) of 10 cmH 2 O; (5) unilateral pulmonary arterial occlusion (PAO); and (6) bronchial arterial occlusion (BAO). Control t/sub 1/2/ was 25 +/- 5 min and did not change in the repeat control, increased frequency, or BAO experiments. PEEP markedly decreased t/sub 1/2/ to 13 +/- 3 min (P < 0.01), and PAO increased it to 37 +/- 6 min (P < 0.05). We conclude that clearance from the lungs by our method is uninfluenced by increased frequency, increases markedly with PEEP, and depends on pulmonary, not bronchial, blood flow

  12. Allometric Scaling of Clearance in Paediatric Patients: When Does the Magic of 0.75 Fade?

    NARCIS (Netherlands)

    Calvier, E.A.M. (Elisa A. M.); E.H.J. Krekels (Elke); P.A.J. Välitalo (Pyry A. J.); A. Rostami-Hodjegan; D. Tibboel (Dick); M. Danhof (Meindert); C.A.J. Knibbe (Catherijne)

    2017-01-01

    textabstractAllometric scaling on the basis of bodyweight raised to the power of 0.75 (AS0.75) is frequently used to scale size-related changes in plasma clearance (CLp) from adults to children. A systematic assessment of its applicability is undertaken for scenarios considering size-related changes

  13. Allometric Scaling of Clearance in Paediatric Patients : When Does the Magic of 0.75 Fade?

    NARCIS (Netherlands)

    Calvier, E.A.M.; Krekels, E.H.J.; Välitalo, P.A.J.; Rostami-Hodjegan, A.; Tibboel, D.; Danhof, M.; Knibbe, C.A.J.

    2016-01-01

    Allometric scaling on the basis of bodyweight raised to the power of 0.75 (AS0.75) is frequently used to scale size-related changes in plasma clearance (CLp) from adults to children. A systematic assessment of its applicability is undertaken for scenarios considering size-related changes with and

  14. Duodenal acid clearance in humans : Observations made with intraluminal impedance recording

    NARCIS (Netherlands)

    Savoye, G; Oors, J; Smout, A

    Duodenal acid clearance appears to be involved not only in the pathogenesis of duodenal ulcer disease but also in functional dyspepsia. Duodenal contractile activity can help to maintain neutral pH in the duodenum by mixing acid with bicarbonate or by aborally transporting the acid load.

  15. Duodenal acid clearance in humans: observations made with intraluminal impedance recording

    NARCIS (Netherlands)

    Savoye, Guillaume; Oors, Jac; Smout, André

    2005-01-01

    Duodenal acid clearance appears to be involved not only in the pathogenesis of duodenal ulcer disease but also in functional dyspepsia. Duodenal contractile activity can help to maintain neutral pH in the duodenum by mixing acid with bicarbonate or by aborally transporting the acid load.

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  18. Endogenous versus exogenous lithium clearance for evaluation of dopamine-induced changes in renal tubular function

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal; Fogh-Andersen, N; Strandgaard, S

    1996-01-01

    1. The present randomized, double-blind cross-over study compared endogenous and exogenous lithium clearance (CLi) for estimation of the effect of dopamine on tubular sodium reabsorption. Twelve normal, salt-repleted male subjects were investigated on three different occasions with either placebo...... that the two methods are interchangeable for estimation of dopamine-induced changes in tubular function....

  19. Analysis of grease contamination influence on the internal radial clearance of ball bearings by thermographic inspection

    Directory of Open Access Journals (Sweden)

    Mišković Žarko Z.

    2016-01-01

    Full Text Available One of the most important factors influencing ball bearings service life is its internal radial clearance. However, this parameter is also very complex because it depends on applied radial load and ball bearings dimensions, surface finish and manufacturing materials. Thermal condition of ball bearings also significantly affects internal radial clearance. Despite many researches performed in order to find out relevant facts about different aspects of ball bearings thermal behaviour, only few of them are dealing with the real working conditions, where high concentration of solid contaminant particles is present. That’s why the main goal of research presented in this paper was to establish statistically significant correlation between ball bearings temperatures, their working time and concentration of contaminant particles in their grease. Because of especially difficult working conditions, the typical conveyor idlers bearings were selected as representative test samples and appropriate solid particles from open pit coal mines were used as artificial contaminants. Applied experimental methodology included thermographic inspection, as well as usage of custom designed test rig for ball bearings service life testing. Finally, by obtained experimental data processing in advanced software, statistically significant mathematical correlation between mentioned bearings characteristics was determined and applied in commonly used internal radial clearance equation. That is the most important contribution of performed research - the new equation and methodology for ball bearings internal clearance determination which could be used for eventual improvement of existing bearings service life equations. [Projekat Ministarstva nauke Republike Srbije, br. TR35029 i br. TR14033

  20. 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

    The whole body clearance of noradrenaline (NA) was measured in seven patients pre- and postoperatively. L-3H-NA was infused intravenously for 90 min and steady-state concentrations of L-3H-NA were measured in both arterial and peripheral venous blood. Preoperatively, in the resting supine position...

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  3. Anti-beta2 glycoprotein I antibodies cause inflammation and recruit dendritic cells in platelet clearance.

    Science.gov (United States)

    Bondanza, A; Manfredi, A A; Zimmermann, V S; Iannacone, M; Tincani, A; Balestrieri, G; Sabbadini, M G; Querini, P R

    2001-11-01

    Scavenger phagocytes are mostly responsible for the in vivo clearance of activated or senescent platelets. In contrast to other particulate substrates, the phagocytosis of platelets does not incite proinflammatory responses in vivo. This study assessed the contribution of macrophages and dendritic cells (DCs) to the clearance of activated platelets. Furthermore, we verified whether antibodies against the beta2 Glycoprotein I (beta2GPI), which bind to activated platelets, influence the phenomenon. DCs did not per se intemalise activated platelets. In contrast, macrophages efficiently phagocytosed platelets. In agreement with the uneventful nature of the clearance of platelets in vivo, phagocytosing macrophages did not release IL-1beta, TNF-alpha, or IL-10, beta2GPI bound to activated platelets and was required for their recognition by anti-beta2GPI antibodies. DCs internalised platelets opsonised by anti-beta2GPI antibodies. The phagocytosis of opsonised platelets determined the release of TNF-alpha and IL-1beta by DCs and macrophages. Phagocytosing macrophages, but not DCs, secreted the antiinflammatory cytokine IL-10. We conclude that anti-beta2GPI antibodies cause inflammation during platelet clearance and shuttle platelet antigens to antigen presenting DCs.

  4. A bodyweight-dependent allometric exponent for scaling clearance across the human life-span

    NARCIS (Netherlands)

    C. Wang (Chenguang); M.Y. Peeters (Mariska); K.M. Allegaert (Karel); H.J. Blussé van Oud-Alblas (Heleen); E.H.J. Krekels (Elke); D. Tibboel (Dick); M. Danhof (Meindert); C.A.J. Knibbe (Catherijne)

    2012-01-01

    textabstractPurpose: To explore different allometric equations for scaling clearance across the human life-span using propofol as a model drug. Methods: Data from seven previously published propofol studies ((pre)term neonates, infants, toddlers, children, adolescents and adults) were analysed using

  5. Glucose clearance in aged trained skeletal muscle during maximal insulin with superimposed exercise

    DEFF Research Database (Denmark)

    Dela, Flemming; Mikines, K J; Larsen, J J

    1999-01-01

    Insulin and muscle contractions are major stimuli for glucose uptake in skeletal muscle and have in young healthy people been shown to be additive. We studied the effect of superimposed exercise during a maximal insulin stimulus on glucose uptake and clearance in trained (T) (1-legged bicycle...

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    2011-06-28

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  7. Megalin and cubilin are endocytic receptors involved in renal clearance of hemoglobin

    DEFF Research Database (Denmark)

    Gburek, Jakub; Verroust, Pierre J; Willnow, Thomas E

    2002-01-01

    The kidney is the main site of hemoglobin clearance and degradation in conditions of severe hemolysis. Herein it is reported that megalin and cubilin, two epithelial endocytic receptors, mediate the uptake of hemoglobin in renal proximal tubules. Both receptors were purified by use of hemoglobin...

  8. Influence of chest background on pulmonary 99m Tc-DTPA clearance in interstitial lung disease

    International Nuclear Information System (INIS)

    Ishizaka, Akitoshi; Kanazawa, Minoru; Suzuki, Yukio; Hasegawa, Naoki; Kubo, Atsushi; Kawashiro, Takeo

    1992-01-01

    The authors examined the effect of chest extracellular 99m T c -diethylenetriamine pentaacetate (DTPA) as a background in the measurement of pulmonary 99m T c -DTPA clearance in patients with interstitial lung disease (ILD). Eight healthy nonsmokers (HN) and eight patients with ILD were studied. They monitored changes in gamma counts after the inhalation of 99m T c -DTPA aerosol by using a gamma camera placed over the anterior chest. The rate constant of pulmonary 99m T c -DTPA clearance (k; %/min) was assessed by calculating the slope of the decrease in the gamma counts. The chest background, estimated by 99m T c -DTPA intravenous injection, was subtracted from the original data to obtain the corrected DTPA clearance (k c ; %/min). In patients with ILD, k was significantly greater [2.19 ± 1.03 (SD) %/min; n = 8] compared with HN (0.86 ± 0.17%/min; n = 8; P c was also greater (2.80 ± 1.15%/min; n = 8; P c among all subjects (r = 0.987, P 99m T c -DTPA clearance. 16 refs., 2 figs., 2 tabs

  9. Clearance of the rodent retrovirus, XMuLV, by protein A chromatography.

    Science.gov (United States)

    Bach, Julia; Connell-Crowley, Lisa

    2015-04-01

    Protein A chromatography is the most common unit operation used in the manufacture of therapeutic monoclonal antibodies (mAbs) due to its high affinity and specificity for the IgG Fc domain. However, protein A chromatography is often not effective for viral clearance. Typical log reduction values (LRV) for the model retrovirus XMuLV range between 1 and 4 logs, while effective steps such as viral filtration can achieve 5-7 logs of clearance. XMuLV LRVs obtained on protein A are reproducible for a given mAb, but can vary widely for different mAbs, even with the same operating conditions. In order to understand the mechanism of XMuLV clearance on protein A, we have investigated its partitioning on Mabselect SuRe protein A resin and explored how the virus interacts with resin, product, and impurities. The results show that XMuLV has some interaction with the resin backbone and ligand, but also appears to bind to and coelute with the mAb. The interaction with product was further examined by evaluating the effect of feed conditions, loading, and different washes on XMuLV partitioning on the column. Understanding the mechanism of XMuLV removal on a protein A, resin provides insight into the variability and low viral clearance of this step and suggests ways in which the removal of virus by this step can be improved. © 2015 Wiley Periodicals, Inc.

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    2012-05-18

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  11. Use of Fluorescently Labeled Algae to Measure the Clearance Rate of the Rotifer Keratella-Cochlearis

    NARCIS (Netherlands)

    Telesh, I.V.; Ooms-Wilms, A.L.; Gulati, R.D.

    1995-01-01

    1. Fluorescently labelled algae (FLA) were used to measure clearance rates of the rotifer Keratella cochlearis. The freshwater algae Chlorella vulgaris and Stichococcus bacillaris were labelled with a fluorescent dye, 5-(4,6-dichlorotriazin-2- yl) aminofluorescein (DTAF), following a modified

  12. Impact of CYP2C8*3 on paclitaxel clearance

    DEFF Research Database (Denmark)

    Bergmann, T K; Brasch-Andersen, C; Gréen, H

    2011-01-01

    ; the explanation is probably the advantage of using both unbound paclitaxel clearance and a population of patients of same gender. No significant association was found for the ABCB1 variants C1236T, G2677T/A and C3435T. Secondarily, other candidate single-nucleotide polymorphisms were explored with possible...

  13. Renal I-131-hippurate clearance overestimates true renal blood flow in the instrumented conscious dog

    NARCIS (Netherlands)

    Visscher, CA; DeZeeuw, D; Navis, G; VanZanten, AK; DeJong, PE; Huisman, RM

    We evaluated renal I-131-hippurate clearance (ERPF(hip)) as a measure of renal blood flow (RBF) in chronically instrumented conscious dogs. When adjusted for renal hippurate extraction (E(hip), 0.77 +/- 0.01) and hematocrit (Hct, 39.7 +/- 1%), calculated RBF(hip) (656 +/- 37 ml/min) markedly

  14. Influence of a low-frequency magnetic field on the 133Xe clearance of the gastrocnemius

    International Nuclear Information System (INIS)

    Stroehmann, F.; Strangfeld, D.; Conradi, E.

    1985-01-01

    In 14 patients with disturbances of the arterial blood supply the influence of a 50 Hz changing magnetic field of 24 mT on the microcirculation of the musculature was tested by means of 133 Xe clearance. An influence of the magnetic field could not be proved. (author)

  15. Vegetation clearance distances to prevent wildland fire caused damage to telecommunication and power transmission infrastructure (2)

    Science.gov (United States)

    B. W. Butler; T. Wallace; J. Hogge

    2015-01-01

    Towers and poles supporting power transmission and telecommunication lines have collapsed due to heating from wildland fires. Such occurrences have led to interruptions in power or communication in large municipal areas with associated social and political implications as well as increased immediate danger to humans. Vegetation clearance standards for overhead...

  16. Computational Parametric Study of the Axial and Radial Clearances in a Centrifugal Rotary Blood Pump.

    Science.gov (United States)

    Rezaienia, Mohammad Amin; Paul, Gordon; Avital, Eldad; Rothman, Martin T; Korakianitis, Theodosios

    2017-10-23

    In centrifugal rotary blood pumps (RBP), clearances are a critical parameter in determining blood trauma. This study investigates the effect of axial clearance (Cax) and radial clearance (Crad) on the hydrodynamic and hemolytic performance of a centrifugal RBP. A centrifugal pump was parameterized so that it could be defined by geometric variables Cax and Crad. Optimal Latin hypercube sampling was used to determine design points based on Cax, Crad, and rotor speed (ω). For each design point, a computational simulation was conducted to determine efficiency (η) and normalized index of hemolysis (NIH). Next, a response surface (RS) was created to estimate these performance parameters based on the design variables. The results show that for a given Cax, when Crad is decreased, η increases until Crad = 0.15 mm, beyond which η deceases. For a given Crad, Cax has a unimodal relationship with η. The NIH has a unimodal relationship with both Cax and Crad. The mechanisms behind these relationships were investigated by various analytical methods. It was found that vortices in the secondary flow paths were a critical factor in determining efficiency and hemolysis. The optimal clearance values discerned in this study are only valid for the specific impeller geometry and operating conditions analyzed.

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  20. 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.

  1. Impact of Food on Hepatic Clearance of Patients After Endoscopic Sphincterotomy

    Directory of Open Access Journals (Sweden)

    Hoi-Hung Chan

    2009-01-01

    Conclusion: Both fatty and low-fat meals improved hepatic clearance in most of the patients with CBDS after ES, but the response to meals was individualized. Therefore, there is no need to restrict the amount of fat intake for patients who have undergone ES.

  2. Clearance rates of jellyfish and their potential predation impact on zooplankton and fish larvae in a neritic ecosystem (Limfjorden, Denmark)

    DEFF Research Database (Denmark)

    Hansson, L. J.; Moeslund, O.; Kiørboe, Thomas

    2005-01-01

    comparatively low. These data were used to assess the impact of jellyfish predation upon zooplankton and fish larvae in Limfjorden, Denmark. Repeated sampling of zooplankton, fish larvae and medusae was undertaken during the first half of 2003. Nine taxa of hydromedusae and 4 taxa of scyphomedusae were...... identified. Abundance estimates were combined with estimated clearance rates of individual medusae to calculate potential jellyfish-induced mortality on prey in Limfjorden. Copepoda was used as a model prey group to estimate the collective predation impact by all medusae. Medusa species with unknown...... clearance potential were given assumed clearance rate values, but the collective predation potential by these species was evaluated to be small. Hydromedusae dominated numerically and had their highest potential clearance impact in spring, but overall jellyfish clearance potential on copepods was low during...

  3. A multi-compartment model for slow bronchial clearance of insoluble particles - Extension of the ICRP human respiratory tract models

    International Nuclear Information System (INIS)

    Sturm, R.; Hofmann, W.

    2006-01-01

    To incorporate the various mechanisms that are presently assumed to be responsible for the experimentally observed slow bronchial clearance into the HRTM, a multi-compartment model was developed to simulate the clearance of insoluble particles in the tracheobronchial tree of the human lung. The new model considers specific mass transfer paths that may play an important role for slow bronchial clearance. These include the accumulation of particulate mass in the peri-ciliary sol layer, phagocytosis of stored particles by airway macrophages and uptake of deposited mass by epithelial cells. Besides the gel layer representing fast mucociliary clearance, all cellular and non-cellular units involved in the slow clearance process are described by respective compartments that are connected by specific transfer rates. The gastrointestinal tract and lymph nodes are included into the model as final accumulation compartments, to which mass is transferred via the airway route and the transepithelial path. Predicted retention curves correspond well with previously published data. (authors)

  4. Reduced erythrocyte susceptibility and increased host clearance of young parasites slows Plasmodium growth in a murine model of severe malaria

    Science.gov (United States)

    Khoury, David S.; Cromer, Deborah; Best, Shannon E.; James, Kylie R.; Sebina, Ismail; Haque, Ashraful; Davenport, Miles P.

    2015-05-01

    The best correlate of malaria severity in human Plasmodium falciparum (Pf) infection is the total parasite load. Pf-infected humans could control parasite loads by two mechanisms, either decreasing parasite multiplication, or increasing parasite clearance. However, few studies have directly measured these two mechanisms in vivo. Here, we have directly quantified host clearance of parasites during Plasmodium infection in mice. We transferred labelled red blood cells (RBCs) from Plasmodium infected donors into uninfected and infected recipients, and tracked the fate of donor parasites by frequent blood sampling. We then applied age-based mathematical models to characterise parasite clearance in the recipient mice. Our analyses revealed an increased clearance of parasites in infected animals, particularly parasites of a younger developmental stage. However, the major decrease in parasite multiplication in infected mice was not mediated by increased clearance alone, but was accompanied by a significant reduction in the susceptibility of RBCs to parasitisation.

  5. 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.

  6. The value of level III clearance in patients with axillary and sentinel node positive breast cancer.

    LENUS (Irish Health Repository)

    Dillon, Mary F

    2012-02-01

    BACKGROUND: The value of level III axillary clearance is contentious, with great variance worldwide in the extent and levels of clearance performed. OBJECTIVE: To determine rates of level III positivity in patients undergoing level I-III axillary clearance, and identify which patients are at highest risk of involved level III nodes. METHODS: From a database of 2850 patients derived from symptomatic and population-based screening service, 1179 patients who underwent level I-III clearance between the years 1999-2007 were identified. The pathology, surgical details, and prior sentinel nodes biopsies of patients were recorded. RESULTS: Eleven hundred seventy nine patients had level I-III axillary clearance. Of the patients, 63% (n = 747) were node positive. Of patients with node positive disease, 23% (n = 168) were level II positive and 19% (n = 141) were level III positive. Two hundred fifty patients had positive sentinel node biopsies prior to axillary clearance. Of these, 12% (n = 30) and 9% (n = 22) were level II and level III positive, respectively. On multivariate analysis, factors predictive of level III involvement in patients with node positive disease were tumor size (P < 0.001, OR = 1.36; 95% CI: 1.2-1.5), invasive lobular disease (P < 0.001, OR = 3.6; 95% CI: 1.9-6.95), extranodal extension (P < 0.001, OR = 0.27; 95% CI: 0.18-0.4), and lymphovascular invasion (P = 0.04, OR = 0.58; 95% CI: 0.35-1). Lobular invasive disease (P = 0.049, OR = 4.1; 95% CI: 1-16.8), extranodal spread (P = 0.003, OR = 0.18; 95% CI: 0.06-0.57), and having more than one positive sentinel node (P = 0.009, OR = 4.9; 95% CI: 1.5-16.1) were predictive of level III involvement in patients with sentinel node positive disease. CONCLUSION: Level III clearance has a selective but definite role to play in patients who have node positive breast carcinoma. Pathological characteristics of the primary tumor are of particular use in identifying those who are at various risk of level III nodal

  7. Methadone pharmacogenetics: CYP2B6 polymorphisms determine plasma concentrations, clearance and metabolism

    Science.gov (United States)

    Kharasch, Evan D.; Regina, Karen J.; Blood, Jane; Friedel, Christina

    2015-01-01

    Background Interindividual variability in methadone disposition remains unexplained, and methadone accidental overdose in pain therapy is a significant public health problem. Cytochrome P4502B6 (CYP2B6) is the principle determinant of clinical methadone elimination. The CYP2B6 gene is highly polymorphic, with several variant alleles. CYP2B6.6, the protein encoded by the CYP2B6*6 polymorphism, deficiently catalyzes methadone metabolism in vitro. This investigation determined the influence of CYP2B6*6, and other allelic variants encountered, on methadone concentrations, clearance, and metabolism. Methods Healthy volunteers in genotype cohorts CYP2B6*1/*1 (n=21), CYP2B6*1/*6 (n=20), and CYP2B6*6/*6 (n=17), and also CYP2B6*1/*4 (n=1), CYP2B6*4/*6 (n=3), CYP2B6*5/*5 (n=2) subjects received single doses of intravenous and oral methadone. Plasma and urine methadone and metabolite concentrations were determined by tandem mass spectrometry. Results Average S-methadone apparent oral clearance was 35 and 45% lower in CYP2B6*1/*6 and CYP2B6*6/*6 genotypes, respectively, compared with CYP2B6*1/*1, and R-methadone apparent oral clearance was 25 and 30% lower. R- and S-methadone apparent oral clearance was 3- and 4-fold greater in CYP2B6*4 carriers. Intravenous and oral R- and S-methadone metabolism was significantly lower in CYP2B6*6 carriers compared with CYP2B6*1 homozygotes, and greater in CYP2B6*4 carriers. Methadone metabolism and clearance were lower in African-Americans due to the CYP2B6*6 genetic polymorphism. Conclusions CYP2B6 polymorphisms influence methadone plasma concentrations, due to altered methadone metabolism and thus clearance. Genetic influence is greater for oral than intravenous, and S- than R-methadone. CYP2B6 pharmacogenetics explains, in part, interindividual variability in methadone elimination. CYP2B6 genetic effects on methadone metabolism and clearance may identify subjects at risk for methadone toxicity and drug interactions. PMID:26389554

  8. The association of medication use with clearance or persistence of oral HPV infection.

    Science.gov (United States)

    Lam, Jennifer O; Sugar, Elizabeth A; Cranston, Ross D; Weber, Kathleen M; Burk, Robert D; Wiley, Dorothy J; Reddy, Susheel; Margolick, Joseph B; Strickler, Howard D; Wentz, Alicia; Jacobson, Lisa; Coles, Christian L; Bream, Jay H; Rositch, Anne F; Guo, Yingshi; Xiao, Weihong; Gillison, Maura L; D'Souza, Gypsyamber

    2016-12-01

    Persistent oral human papillomavirus (HPV) infection increases risk for oropharyngeal carcinoma, and people living with HIV have higher rates of oral HPV infection and related cancers. Some prescription medications have immunomodulatory effects, but the impact of medication use on oral HPV natural history is unknown. Scope ® oral rinse-and-gargle samples were collected semi-annually from 1,666 participants and tested for 37 types of oral HPV DNA using PCR; 594 HPV-infected participants with 1,358 type-specific oral HPV infections were identified. Data were collected on recent (past 6 months) use of medications. The relationship between medication use and oral HPV clearance was evaluated using Wei-Lin-Weissfeld regression, adjusting for biologic sex, prevalent versus incident infection, age, HIV status and CD4+ T cell count. Out of 11 medications examined, oral HPV clearance was significantly reduced in participants reporting recent use of antipsychotics (HR 0.75, 95% CI 0.57-0.99), anxiolytics/sedatives (HR 0.78, 95% CI 0.63-0.96) and antidepressants (HR 0.82, 95% CI 0.67-0.999). Among antipsychotics users, effect modification by HIV status was observed, with reduced clearance in HIV-infected (HR 0.67, 95% CI 0.49-0.91), but not HIV-uninfected participants (p-interaction = 0.009). After adjusted analysis, antipsychotic use remained significantly associated with reduced oral HPV clearance overall (aHR 0.75, 95% CI 0.57-0.99), and when restricted to only HIV-infected participants (aHR 0.66, 95% CI 0.48-0.90). After adjustment, anxiolytic/sedative use and antidepressant use were no longer significantly associated with reduced oral HPV clearance. Some medications were associated with decreased oral HPV clearance, most notably antipsychotic medications. These medications are prescribed for conditions that may have immunomodulating effects, so characteristics of underlying illness may have partially contributed to reduced oral HPV clearance.

  9. 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

  10. Analysis of conservativity analysis for clearance levels. Final report; Konservativitaetsanalysen bei Freigabegrenzwerten. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    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 (the reference). This means that the clearance levels for gamma emitting nuclides are not overly restrictive. The radiological model for the exposure via the groundwater pathway is much more conservative (concerning mainly beta emitting nuclides). Although radiologically justified

  11. The UK Nuclear Industry Code of Practice on Clearances and Exemptions

    International Nuclear Information System (INIS)

    Owen, D.

    2004-01-01

    In 2001, the major nuclear organisations in the United Kingdom started development of a document that would identify and facilitate consistent the application of good practice within the industry for clearing and sentencing of articles, substances and wastes which may be clean, or radioactive at very low levels below thresholds of regulatory control. The document includes: (i) Clarification of the industry's interpretation of legislation associated with the clearance and sentencing of articles, substances and wastes which are or have the potential to have been contaminated by radioactivity or activated by nuclear radiations; (ii) Industry agreement on what is considered to be the good practice where legislation is imprecise or unclear, (iii) A standard management framework, adopted by all organisations within the nuclear industry, that should justify safe and efficient clearance of potentially radioactive articles, substances and wastes; and (IV) Agreed guidance on the principles, processes and practices which should be followed for clearances and sentencing The Document mandates a system that allows articles and substances to be released from further control, where this is appropriate, using robust radiological protection principles. The need to avoid sentencing of clean materials as radioactive waste where this is not appropriate, the primacy of bulk, rather than surface radioactivity clearance criteria, and the need to disallow such clearances until all relevant legislation has been satisfied, are all clear principles contained within the document. An interim issue of the Code of Practice was issued in May 2003. This version has been formally adopted by all of the major users of radioactive material in the United Kingdom, and has two main objectives: -Trial use of the concepts at the working level, and - As a basis for further discussion with interested stakeholders. The paper summarises: - How the interim version of the Code of Practice was developed; - The

  12. Serum albumin and creatinine clearance rate among smear positive pulmonary tuberculosis patients in Bangladesh.

    Science.gov (United States)

    Hoque, M R; Chakraborty, P K; Paul, U K; Sarkar, S; Akhter, S; Shahidullah, S M; Gautam, B; Sultana, S; Ferdous, N; Samsunnahar, M

    2014-07-01

    This case control study was carried out in the Department of Biochemistry, Mymensingh Medical College in cooperation with the Outpatient Department and Medicine Units of Mymensingh Medical College Hospital, Fulbaria Upazilla Health Complex, Mymensingh and some DOTS centers of BRAC, a non-government organization during the period of July 2006 to June 2007. The aim of the study was to explore the status of serum albumin & creatinine clearance levels in smear positive Bangladeshi pulmonary tuberculosis patients as a means to monitor the possibility of management of these patients as these levels decrease significantly. Serum albumin level was investigated in TB patients for monitoring the nutritional status of TB patients and also for the adjustment of serum calcium level. Creatinine clearance rate was investigated in TB patients for monitoring the impairment of renal function and nutritional depletion in tuberculosis patients. A total of 120 people of different age groups were included in this study. Subjects were divided into two groups- Group I (Control; n=60) - apparently healthy people selected matching by age, sex and socioeconomic status with the cases and Group II (Case; n=60) - people with smear positive pulmonary tuberculosis. Serum albumin was estimated by colorimetric principle. Serum creatinine was also estimated by colorimetric principle & creatinine clearance rate was estimated from serum creatinine by Cockcroft- Gault equation. Statistical analysis was done by using SPSS windows package. Among the groups, mean±SD of serum albumin in Group II (3.74±0.44gm/dl) was significantly lower (pcreatinine clearance rate in Group II (35.36±8.29ml/min) was also significantly lower than that in Group I (84.16±20.20ml/min). It is evident from the study that serum albumin & creatinine clearance rate levels significantly decrease in smear positive Bangladeshi pulmonary tuberculosis patients.

  13. The metabolic clearance rate of corticosterone in lean and obese male Zucker rats

    International Nuclear Information System (INIS)

    White, B.D.; Corll, C.B.; Porter, J.R.

    1989-01-01

    The obese Zucker rat is an animal model of human juvenile-onset obesity. These rats exhibit numerous endocrine and metabolic abnormalities. Adrenalectomy of obese rats has been shown to reduce or reverse several of these abnormalities, thereby implying that corticosterone may contribute to the expression of obesity in this animal. Furthermore, it has been shown that the circadian rhythm of plasma corticosterone is disturbed in obese Zucker rats resulting in elevated morning plasma corticosterone concentrations in obese rats as compared to lean rats. In a effort to better elucidate the mechanism of the elevated morning levels of plasma corticosterone, the metabolic clearance rate of corticosterone was determined in the morning for lean and obese male Zucker rats (12 to 20 weeks). Additionally, the biliary and urinary excretion of labeled corticosterone and/or its metabolites were determined. The metabolic clearance rate of corticosterone was significantly greater in obese rats than in their lean counterparts. Both the metabolic clearance rate and the volume of compartments significantly correlated with body weight. No correlation was found between body weight and the elimination rate constant. The increased metabolic clearance rate of obese rats appeared to be due to an increase in the physiologic distribution of corticosterone and not to an alteration in the enzymes responsible for corticosterone metabolism. It appears that the metabolic clearance rate of corticosterone in obese Zucker rats does not contribute to elevated morning concentrations of plasma corticosterone previously observed in these animals. It suggests that the adrenal corticosterone secretion rate must actually be greater than one would expect from the plasma corticosterone concentrations alone

  14. Spontaneous pharyngeal Chlamydia trachomatis RNA clearance. A cross-sectional study followed by a cohort study of untreated STI clinic patients in Amsterdam, The Netherlands

    NARCIS (Netherlands)

    van Rooijen, Martijn S.; van der Loeff, Maarten F. Schim; Morré, Servaas A.; van Dam, Alje P.; Speksnijder, Arjen G. C. L.; de Vries, Henry J. C.

    2015-01-01

    Objectives Pharyngeal Chlamydia trachomatis (chlamydia) might contribute to ongoing chlamydia transmission, yet data on spontaneous clearance duration are rare. We examined the prevalence, spontaneous clearance, chlamydial DNA concentration and genotypes of pharyngeal chlamydia among clinic patients

  15. Replication and clearance of respiratory syncytial virus - Apoptosis is an important pathway of virus clearance after experimental infection with bovine respiratory syncytial virus

    DEFF Research Database (Denmark)

    Viuff, B.; Tjørnehøj, Kirsten; Larsen, Lars Erik

    2002-01-01

    and the infections with human respiratory syncytial. virus and BRSV have similar clinical, pathological, and epidemiological characteristics. In this study we used experimental BRSV infection in calves as a model of respiratory syncytial virus infection to demonstrate important aspects of viral replication...... and clearance in a natural target animal. Replication of BRSV was demonstrated in the luminal part of the respiratory epithelial cells and replication in the upper respiratory tract preceded the replication in the lower respiratory tract. Virus excreted to the lumen of the respiratory tract was cleared...

  16. The effects of female sex, viral genotype, and IL28B genotype on spontaneous clearance of acute hepatitis C virus infection

    NARCIS (Netherlands)

    Grebely, Jason; Page, Kimberly; Sacks-Davis, Rachel; van der Loeff, Maarten Schim; Rice, Thomas M.; Bruneau, Julie; Morris, Meghan D.; Hajarizadeh, Behzad; Amin, Janaki; Cox, Andrea L.; Kim, Arthur Y.; McGovern, Barbara H.; Schinkel, Janke; George, Jacob; Shoukry, Naglaa H.; Lauer, Georg M.; Maher, Lisa; Lloyd, Andrew R.; Hellard, Margaret; Dore, Gregory J.; Prins, Maria; Lauer, Georg; Morris, Meghan; Hahn, Judy; Rilla, Megan; Alavi, Maryam; Bouchard, Rachel; Evans, Jennifer; Grady, Bart; Aneja, Jasneet; Teutsch, Suzy; White, Bethany; Wells, Brittany; Zang, Geng; Applegate, Tanya; Matthews, Gail; Yeung, Barbara; Prince, Leslie Erin; Roy, Elise; Bates, Anna; Enriquez, Jarliene; Chow, Sammy; McCredie, Luke; Aitken, Campbell; Doyle, Joseph; Spelman, Tim

    2014-01-01

    Although 20%-40% of persons with acute hepatitis C virus (HCV) infection demonstrate spontaneous clearance, the time course and factors associated with clearance remain poorly understood. We investigated the time to spontaneous clearance and predictors among participants with acute HCV using Cox

  17. Comparison of myocardial 201Tl clearance after maximal and submaximal exercise: implications for diagnosis of coronary disease: concise communication

    International Nuclear Information System (INIS)

    Massie, B.M.; Wisneski, J.; Kramer, B.; Hollenberg, M.; Gertz, E.; Stern, D.

    1982-01-01

    Recently the quantitation of regional 201 Tl clearance has been shown to increase the sensitivity of the scintigraphic detection of coronary disease. Although 201 Tl clearance rates might be expected to vary with the degree of exercise, this relationship has not been explored. We therefore evaluated the rate of decrease in myocardial 201 Tl activity following maximal and submaximal stress in seven normal subjects and 21 patients with chest pain, using the seven-pinhole tomographic reconstruction technique. In normals, the mean 201 Tl clearance rate declined from 41% +/- 7 over a 3-hr period with maximal exercise to 25% +/- 5 after 3 hr at a submaximal level (p less than 0.001). Similar differences in clearance rates were found in the normally perfused regions of the left ventricle in patients with chest pain, depending on whether or not a maximal end point (defined as either the appearance of ischemia or reaching 85% of age-predicted heart rate) was achieved. In five patients who did not reach these end points, 3-hr clearance rates in uninvolved regions averaged 25% +/- 2, in contrast to a mean of 38% +/- 5 for such regions in 15 patients who exercised to ischemia or an adequate heart rate. These findings indicate that clearance criteria derived from normals can be applied to patients who are stressed maximally, even if the duration of exercise is limited, but that caution must be used in interpreting clearance rates in those who do not exercise to an accepted end point

  18. Dynamic clearance measure to evaluate locomotor and perceptuo-motor strategies used for obstacle circumvention in a virtual environment.

    Science.gov (United States)

    Darekar, Anuja; Lamontagne, Anouk; Fung, Joyce

    2015-04-01

    Circumvention around an obstacle entails a dynamic interaction with the obstacle to maintain a safe clearance. We used a novel mathematical interpolation method based on the modified Shepard's method of Inverse Distance Weighting to compute dynamic clearance that reflected this interaction as well as minimal clearance. This proof-of-principle study included seven young healthy, four post-stroke and four healthy age-matched individuals. A virtual environment designed to assess obstacle circumvention was used to administer a locomotor (walking) and a perceptuo-motor (navigation with a joystick) task. In both tasks, participants were asked to navigate towards a target while avoiding collision with a moving obstacle that approached from either head-on, or 30° left or right. Among young individuals, dynamic clearance did not differ significantly between obstacle approach directions in both tasks. Post-stroke individuals maintained larger and smaller dynamic clearance during the locomotor and the perceptuo-motor task respectively as compared to age-matched controls. Dynamic clearance was larger than minimal distance from the obstacle irrespective of the group, task and obstacle approach direction. Also, in contrast to minimal distance, dynamic clearance can respond differently to different avoidance behaviors. Such a measure can be beneficial in contrasting obstacle avoidance behaviors in different populations with mobility problems. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Factors associated with early mycological clearance in HIV-associated cryptococcal meningitis.

    Directory of Open Access Journals (Sweden)

    Fátima Concha-Velasco

    Full Text Available The first-line combination therapy for HIV-associated cryptococcal meningitis (CM, a condition of high mortality particularly in the first two weeks of treatment, consists of amphotericin B plus flucytosine (5-FC. Given that 5-FC remains unavailable in many countries, the knowledge of factors influencing mycological clearance in patients treated with second-line therapy could contribute to effective management.To determine the factors associated with the clearance of Cryptococcus sp. from the cerebrospinal fluid by the second week of effective antifungal therapy (early mycological clearance in HIV-associated CM.Retrospective cohort study based on secondary data corresponding to HIV-associated CM cases hospitalized at a tertiary health care center in Lima, Peru where 5-FC remains unavailable. Risk factors associated with early mycological clearance were analyzed by generalized linear regression models.From January 2000 to December 2013, 234 individuals were discharged with a diagnosis of HIV-associated CM; in 215 we retrieved the required data. The inpatient mortality was 20% (43/215, 15 of them in the first two weeks of treatment. In the final model (157 cases, adjusted for age, previous episode of CM, ART use, type of antifungal treatment, raised intracranial pressure, frequency of therapeutic lumbar punctures, baseline fungal burden and treatment period, the factors associated with early mycological clearance were: Amphotericin B deoxycholate plus fluconazole as combination therapy (RR, 1.56; 95% CI, 1.14-2.14; severe baseline intracranial pressure (≥35 cm H2O (RR, 0.57; 95% CI, 0.33-0.99; and baseline fungal burden over 4.5 log10 CFU/mL (RR, 0.61 95% CI: 0.39-0.95.In a setting without access to first-line therapy for CM, the combination therapy with amphotericin B deoxycholate plus fluconazole was positively associated with early mycological clearance, while high fungal burden and severe baseline intracranial pressure were negatively

  20. Environmental aspects of recent trend in managing fusion radwaste: Recycling and clearance, avoiding disposal

    International Nuclear Information System (INIS)

    El-Guebaly, L.

    2007-01-01

    Full text: Since the inception of the fusion projects in the early 1970s, the majority of power plant designs have focused on the disposal of the low-level waste in geological repositories as the main option for handling the replaceable and life-of-plant components, adopting the preferred fission waste management approach. It is timely to develop a new radwaste management framework that takes into account the lessons learned from numerous studies and the environmental, political, and present reality. Along with the political difficulty of constructing new repositories worldwide, the current reality suggests reshaping all aspects of handling the continual stream of fusion radwaste, replacing the disposal option with more environmentally attractive approaches, such as recycling and clearance. These approaches became more technically feasible in recent years with the development of radiation-hardened remote handling (RH) tools and the introduction of the clearance category for slightly radioactive materials by IAEA and national nuclear agencies. We applied all scenarios to selected U.S. fusion studies. While recycling and clearance appeared technically attractive and judged, in some cases, a must requirement to control the radwaste stream, the disposal scheme emerged as the preferred option for a specific IFE component for economic reasons. This suggests that the technical and economic aspects, along with the environmental and safety related concerns, must all be addressed during the selection process of the most suitable waste management approach. To make fusion a viable energy source with minimal environmental impact, we highly recommend recycling and clearing all fusion components, if economically and technologically feasible, avoiding the geological burial approach. Additional tasks should be investigated to enhance prospects for a successful fusion management scheme. These include the key issues and challenges for disposal, recycling, and clearance, the limited