Science.gov

Sample records for aerosol challenge tests

  1. Emery 3004 as a challenge aerosol for HEPA filter testing

    SciTech Connect

    Barber, J.D.; Gilles, D.A.

    1994-02-01

    HEPA filters are used in nuclear facilities for contamination control and air treatment and are constructed to be 99.97% efficient in trapping particles of 0.3 microns or larger in size. Prior to installation at Hanford facilities HEPA filters are tested against the manufacturer`s efficiency specifications by the Hanford Environmental Health Foundation using an aerosol with a monodispersed particle size of 0.3 microns. The oil or material used for generating the aerosol, has historically been Dioctl Phthalate (DOP). But, in 1980 DOP was classified as a suspected carcinogen, and the search for substitute materials was under way. Corn oil produced good quantities of the correct sized particles but it tended to clog the generating equipment; Polyethylene Glycol 400 (PEG) and Dioctl Sebacate (DOS) were also tried but failed for various reasons. Emery 304 was tested and produced a good quantity of correctly sized aerosol and did not clog or damage the equipment in any way. Upon further testing, in September 1992, the DOE Richland Operations authorized the use of Emery 304 for in situ HEPA filter testing on the Hanford site.

  2. Ice-condenser aerosol tests

    SciTech Connect

    Ligotke, M.W.; Eschbach, E.J.; Winegardner, W.K. )

    1991-09-01

    This report presents the results of an experimental investigation of aerosol particle transport and capture using a full-scale height and reduced-scale cross section test facility based on the design of the ice compartment of a pressurized water reactor (PWR) ice-condenser containment system. Results of 38 tests included thermal-hydraulic as well as aerosol particle data. Particle retention in the test section was greatly influenced by thermal-hydraulic and aerosol test parameters. Test-average decontamination factor (DF) ranged between 1.0 and 36 (retentions between {approximately}0 and 97.2%). The measured test-average particle retentions for tests without and with ice and steam ranged between DF = 1.0 and 2.2 and DF = 2.4 and 36, respectively. In order to apparent importance, parameters that caused particle retention in the test section in the presence of ice were steam mole fraction (SMF), noncondensible gas flow rate (residence time), particle solubility, and inlet particle size. Ice-basket section noncondensible flows greater than 0.1 m{sup 3}/s resulted in stable thermal stratification whereas flows less than 0.1 m{sup 3}/s resulted in thermal behavior termed meandering with frequent temperature crossovers between flow channels. 10 refs., 66 figs., 16 tabs.

  3. Test-Aerosol Generator For Calibrating Particle Counters

    NASA Technical Reports Server (NTRS)

    Mogan, Paul A.; Adams, Alois J.; Schwindt, Christian J.; Hodge, Timothy R.; Mallow, Tim J.; Duong, Anh A.; Bukauskas, Vyto V.

    1996-01-01

    Apparatus generates clean, stable aerosol stream for use in testing and calibrating laser-based aerosol-particle counter. Size and concentration of aerosol particles controlled to ensure accurate calibration. Cheap, widely available medical nebulizers used to generate aerosols.

  4. Concluding remarks: challenges for aerosols and climate.

    PubMed

    Murphy, D M

    2013-01-01

    We study aerosols for many reasons, including their effects on human health and climate. For climate, it is important to distinguish between the overall radiative effect of aerosols and the radiative forcing, which has been the anthropogenic change (after rapid atmospheric adjustments) since pre-industrial times. The radiative forcing is in principle much harder to observe than the overall effect because one must understand which particles are natural in today's atmosphere and what aerosols were like in the atmosphere before large-scale human influence. Because we cannot go back and measure the past, the only way to calculate radiative forcing may often require modeling detailed aerosol processes. This is a motivation for many of the processes studied at the Faraday Discussion 165. Other processes may need more attention by the aerosol climate community.

  5. Aerosol can puncture device test report

    SciTech Connect

    Leist, K.J.

    1994-10-01

    This test report documents the evaluation of an aerosol can puncture device to replace a system currently identified for use in the WRAP-1 facility. The new system is based upon a commercially available puncture device, as recommended by WHC Fire Protection. With modifications found necessary through the testing program, the Aerosol Can Puncture Device was found able to puncture and drain aerosol cans without incident. Modifications include the addition of a secondary collection bottle and the modification of the can puncture needle. In the course of testing, a variety of absorbents were tested to determine their performance in immobilizing drained fluids. The visibility of the puncture with Non-Destructive Examination techniques were also reviewed.

  6. The Multi-Dimensional Challenge of Validating Remote-Sensing Aerosol-Type Retrievals

    NASA Astrophysics Data System (ADS)

    Kahn, R. A.; Gaitley, B. J.; Limbacher, J.

    2014-12-01

    In addition to aerosol optical depth (AOD), aerosol type is required globally for climate-forcing calculations, constraining aerosol transport models, and other applications. However, validating satellite aerosol type retrievals is much more challenging than testing AOD results, because aerosol type is a more complex quantity, and ground-truth data are far less numerous and generally not as robust. We employ a combination of assessment relative to climatological expectation, statistical comparisons with surface-based observations, and near-coincident field campaign measurements, to evaluate MISR aerosol-type retrieval results. Although the retrievals are not constrained by a priori expectations, there is general regional coherence in the dominant retrieved aerosol types, indicating consistency in the retrieval process. Comparisons with expectation, on a regional, seasonal basis, demonstrate qualitative consistency with regard to particle size (three-to-five bins), shape (spherical vs. non-spherical), and single-scattering albedo (SSA; two-to-four bins) when mid-visible AOD exceeds about 0.15 or 0.2. Statistical comparisons with surface-based sun and sky-scanning photometer retrievals provide both qualitative and quantitative illustration of retrieval sensitivity, identifying strengths and limitations of the MISR Standard Version 22 aerosol product, and pointing to specific areas where improvements could be made. Field campaign results offer the most detailed and robust aerosol-type constraints. They allow us, with the help of the MISR Research aerosol retrieval algorithm, to test the limits of the MISR data information content, which in specific cases substantially exceeds the general sensitivity. This presentation will briefly review the statistical techniques employed and summarize the key MISR aerosol-type retrieval validation results of this work.

  7. Unique DNA-barcoded aerosol test particles for studying aerosol transport

    SciTech Connect

    Harding, Ruth N.; Hara, Christine A.; Hall, Sara B.; Vitalis, Elizabeth A.; Thomas, Cynthia B.; Jones, A. Daniel; Day, James A.; Tur-Rojas, Vincent R.; Jorgensen, Trond; Herchert, Edwin; Yoder, Richard; Wheeler, Elizabeth K.; Farquar, George R.

    2016-03-22

    Data are presented for the first use of novel DNA-barcoded aerosol test particles that have been developed to track the fate of airborne contaminants in populated environments. Until DNATrax (DNA Tagged Reagents for Aerosol eXperiments) particles were developed, there was no way to rapidly validate air transport models with realistic particles in the respirable range of 1–10 μm in diameter. The DNATrax particles, developed at Lawrence Livermore National Laboratory (LLNL) and tested with the assistance of the Pentagon Force Protection Agency, are the first safe and effective materials for aerosol transport studies that are identified by DNA molecules. The use of unique synthetic DNA barcodes overcomes the challenges of discerning the test material from pre-existing environmental or background contaminants (either naturally occurring or previously released). The DNATrax particle properties are demonstrated to have appropriate size range (approximately 1–4.5 μm in diameter) to accurately simulate bacterial spore transport. As a result, we describe details of the first field test of the DNATrax aerosol test particles in a large indoor facility.

  8. Unique DNA-barcoded aerosol test particles for studying aerosol transport

    DOE PAGES

    Harding, Ruth N.; Hara, Christine A.; Hall, Sara B.; ...

    2016-03-22

    Data are presented for the first use of novel DNA-barcoded aerosol test particles that have been developed to track the fate of airborne contaminants in populated environments. Until DNATrax (DNA Tagged Reagents for Aerosol eXperiments) particles were developed, there was no way to rapidly validate air transport models with realistic particles in the respirable range of 1–10 μm in diameter. The DNATrax particles, developed at Lawrence Livermore National Laboratory (LLNL) and tested with the assistance of the Pentagon Force Protection Agency, are the first safe and effective materials for aerosol transport studies that are identified by DNA molecules. The usemore » of unique synthetic DNA barcodes overcomes the challenges of discerning the test material from pre-existing environmental or background contaminants (either naturally occurring or previously released). The DNATrax particle properties are demonstrated to have appropriate size range (approximately 1–4.5 μm in diameter) to accurately simulate bacterial spore transport. As a result, we describe details of the first field test of the DNATrax aerosol test particles in a large indoor facility.« less

  9. Challenges in validating CFD-derived inhaled aerosol deposition predictions.

    PubMed

    Oldham, Michael J

    2006-09-01

    Computational fluid dynamic (CFD) techniques have provided unprecedented opportunity for investigating inhaled particle deposition in realistic human airway geometries. Several recent articles describing local aerosol deposition predictions based upon "validated" CFD models have highlighted the challenges in validating local aerosol deposition predictions. These challenges include: (1) defining what is meant by validation; (2) defining appropriate experimental data for validation; and (3) determining when the agreement is not fortuitous. The term validation has numerous meanings, depending on the field and context in which it is used. For example, in computer programming it means the code executes as intended, to the experimentalist it means predicted results agree with matched experimental measurements, and to the risk assessor it implies that predictions using new parameters can be trusted. Based on the current literature it is not clear that a consensus exists for what constitutes a validated CFD model. It is also not clear what types of experimental data are needed or how closely the CFD input values and experimental conditions should be matched (similar or identical airway geometries, entrance airflow, or aerosol profiles) to validate CFD derived predictions. Due to the complexity of CFD computer codes and the multiplicity of deposition mechanisms, it is possible that total aerosol deposition may be accurately predicted and the resulting local particle deposition patterns are incorrect, or vice versa. Specific examples and suggestions for several challenges to experimentalists and modelers are presented.

  10. High-efficiency particulate air filter test stand and aerosol generator for particle loading studies.

    PubMed

    Arunkumar, R; Hogancamp, Kristina U; Parsons, Michael S; Rogers, Donna M; Norton, Olin P; Nagel, Brian A; Alderman, Steven L; Waggoner, Charles A

    2007-08-01

    This manuscript describes the design, characterization, and operational range of a test stand and high-output aerosol generator developed to evaluate the performance of 30 x 30 x 29 cm(3) nuclear grade high-efficiency particulate air (HEPA) filters under variable, highly controlled conditions. The test stand system is operable at volumetric flow rates ranging from 1.5 to 12 standard m(3)/min. Relative humidity levels are controllable from 5%-90% and the temperature of the aerosol stream is variable from ambient to 150 degrees C. Test aerosols are produced through spray drying source material solutions that are introduced into a heated stainless steel evaporation chamber through an air-atomizing nozzle. Regulation of the particle size distribution of the aerosol challenge is achieved by varying source solution concentrations and through the use of a postgeneration cyclone. The aerosol generation system is unique in that it facilitates the testing of standard HEPA filters at and beyond rated media velocities by consistently providing, into a nominal flow of 7 standard m(3)/min, high mass concentrations (approximately 25 mg/m(3)) of dry aerosol streams having count mean diameters centered near the most penetrating particle size for HEPA filters (120-160 nm). Aerosol streams that have been generated and characterized include those derived from various concentrations of KCl, NaCl, and sucrose solutions. Additionally, a water insoluble aerosol stream in which the solid component is predominantly iron (III) has been produced. Multiple ports are available on the test stand for making simultaneous aerosol measurements upstream and downstream of the test filter. Types of filter performance related studies that can be performed using this test stand system include filter lifetime studies, filtering efficiency testing, media velocity testing, evaluations under high mass loading and high humidity conditions, and determination of the downstream particle size distributions.

  11. Spent fuel sabotage aerosol test program :FY 2005-06 testing and aerosol data summary.

    SciTech Connect

    Gregson, Michael Warren; Brockmann, John E.; Nolte, O. (Fraunhofer institut fur toxikologie und experimentelle Medizin, Germany); Loiseau, O. (Institut de radioprotection et de Surete Nucleaire, France); Koch, W. (Fraunhofer institut fur toxikologie und experimentelle Medizin, Germany); Molecke, Martin Alan; Autrusson, Bruno (Institut de radioprotection et de Surete Nucleaire, France); Pretzsch, Gunter Guido (Gesellschaft fur anlagen- und Reaktorsicherheit, Germany); Billone, M. C. (Argonne National Laboratory, USA); Lucero, Daniel A.; Burtseva, T.; Brucher, W (Gesellschaft fur anlagen- und Reaktorsicherheit, Germany); Steyskal, Michele D.

    2006-10-01

    This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program has been underway for several years. This program provides source-term data that are relevant to some sabotage scenarios in relation to spent fuel transport and storage casks, and associated risk assessments. This document focuses on an updated description of the test program and test components for all work and plans made, or revised, primarily during FY 2005 and about the first two-thirds of FY 2006. It also serves as a program status report as of the end of May 2006. We provide details on the significant findings on aerosol results and observations from the recently completed Phase 2 surrogate material tests using cerium oxide ceramic pellets in test rodlets plus non-radioactive fission product dopants. Results include: respirable fractions produced; amounts, nuclide content, and produced particle size distributions and morphology; status on determination of the spent fuel ratio, SFR (the ratio of respirable particles from real spent fuel/respirables from surrogate spent fuel, measured under closely matched test conditions, in a contained test chamber); and, measurements of enhanced volatile fission product species sorption onto respirable particles. We discuss progress and results for the first three, recently performed Phase 3 tests using depleted uranium oxide, DUO{sub 2}, test rodlets. We will also review the status of preparations and the final Phase 4 tests in this program, using short rodlets containing actual spent fuel from U.S. PWR reactors, with both high- and lower-burnup fuel. These data plus testing results and design are tailored to support and guide, follow-on computer modeling of aerosol dispersal hazards and radiological consequence

  12. Aerosol can puncture device operational test plan

    SciTech Connect

    Leist, K.J.

    1994-05-03

    Puncturing of aerosol cans is performed in the Waste Receiving and Processing Facility Module 1 (WRAP 1) process as a requirement of the waste disposal acceptance criteria for both transuranic (TRU) waste and low-level waste (LLW). These cans have contained such things as paints, lubricating oils, paint removers, insecticides, and cleaning supplies which were used in radioactive facilities. Due to Westinghouse Hanford Company (WHC) Fire Protection concerns of the baseline system`s fire/explosion proof characteristics, a study was undertaken to compare the baseline system`s design to commercially available puncturing devices. While the study found no areas which might indicate a risk of fire or explosion, WHC Fire Protection determined that the puncturing system must have a demonstrated record of safe operation. This could be obtained either by testing the baseline design by an independent laboratory, or by substituting a commercially available device. As a result of these efforts, the commercially available Aerosolv can puncturing device was chosen to replace the baseline design. Two concerns were raised with the system. Premature blinding of the coalescing/carbon filter, due to its proximity to the puncture and draining operation; and overpressurization of the collection bottle due to its small volume and by blinding of the filter assembly. As a result of these concerns, testing was deemed necessary. The objective of this report is to outline test procedures for the Aerosolv.

  13. Vesicular stomatitis virus-based vaccines protect nonhuman primates against aerosol challenge with Ebola and Marburg viruses.

    PubMed

    Geisbert, Thomas W; Daddario-Dicaprio, Kathleen M; Geisbert, Joan B; Reed, Douglas S; Feldmann, Friederike; Grolla, Allen; Ströher, Ute; Fritz, Elizabeth A; Hensley, Lisa E; Jones, Steven M; Feldmann, Heinz

    2008-12-09

    Considerable progress has been made over the last decade in developing candidate preventive vaccines that can protect nonhuman primates against Ebola and Marburg viruses. A vaccine based on recombinant vesicular stomatitis virus (VSV) seems to be particularly robust as it can also confer protection when administered as a postexposure treatment. While filoviruses are not thought to be transmitted by aerosol in nature the inhalation route is among the most likely portals of entry in the setting of a bioterrorist event. At present, all candidate filoviral vaccines have been evaluated against parenteral challenges but none have been tested against an aerosol exposure. Here, we evaluated our recombinant VSV-based Zaire ebolavirus (ZEBOV) and Marburg virus (MARV) vaccines against aerosol challenge in cynomolgus macaques. All monkeys vaccinated with a VSV vector expressing the glycoprotein of ZEBOV were completely protected against an aerosol exposure of ZEBOV. Likewise, all monkeys vaccinated with a VSV vector expressing the glycoprotein of MARV were completely protected against an aerosol exposure of MARV. All control animals challenged by the aerosol route with either ZEBOV or MARV succumbed. Interestingly, disease in control animals appeared to progress slower than previously seen in macaques exposed to comparable doses by intramuscular injection.

  14. Testing the efficiency of aerosol containment during cell sorting.

    PubMed

    Schmid, I; Hultin, L E; Ferbas, J

    2001-05-01

    Production of droplets and microdroplets (aerosols) is part of the normal operation of a cell sorter. These aerosols may contain toxic, carcinogenic, or teratogenic fluorophores or known or unknown pathogens from viable biological specimens. Most newer models of commercially available instruments incorporate features designed to reduce the production of aerosols and prevent their release into the room. This unit presents two protocols for assessment of aerosol containment on jet-in-air flow sorters. In both procedures, lytic T4 bacteriophage is run through the instrument at high concentrations to tag aerosol droplets. The instrument is tested in normal operating mode and in simulated failure mode. Aerosols are detected by plaque formation on susceptible E. coli lawns. With the continuing increase in the sorting of viable human cells, it is vital for cytometrists to be aware of the potential dangers.

  15. Challenges of CPAS Flight Testing

    NASA Technical Reports Server (NTRS)

    Ray, Eric S.; Morris, Aaron L.

    2011-01-01

    The Crew Exploration Vehicle Parachute Assembly System (CPAS) is being designed to land the Orion Crew Module (CM) at a safe rate of descent at splashdown via a series of Drogue, Pilot, and Main parachutes. Because Orion is considerably larger and heavier than Apollo, many of the flight test techniques developed during the Apollo program must be modified. The Apollo program had a dedicated C-133 aircraft, which was modified to allow a simple airdrop of "boilerplate" flight test vehicles. However, the CPAS program must use either commercial or military assets with minimal modifications to airframes or procedures. Conceptual envelopes from 2-Degree Of Freedom trajectories are presented for several existing and novel architectures. Ideally, the technique would deliver a representative capsule shape to the desired altitude and dynamic pressure at test initiation. However, compromises must be made on the characteristics of trajectories or the fidelity of test articles to production hardware. Most of the tests to date have used traditional pallet and weight tub or missile-shaped test vehicles. New test vehicles are being designed to better incorporate Orion structural components and deploy parachutes in a more representative fashion. The first attempt to test a capsule-shaped vehicle failed due to unexpected events while setting up the test condition through a series of complex procedures. In order to avoid the loss of another expensive test article which will delay the program, simpler deployment methods are being examined and more positive control of the vehicle will be maintained. Existing challenges include interfacing with parent aircraft, separating test vehicles, achieving test conditions, and landing within limited test ranges. All these challenges must be met within cost and schedule limits.

  16. Quantitative respirator fit testing: dynamic pressure versus aerosol measurement.

    PubMed

    Carpenter, D R; Willeke, K

    1988-10-01

    A noninvasive, fast, inexpensive new fit testing method has been invented which relates the slope of the pressure decay inside a respirator during breath-holding to the fit of the respirator on the wearer's face. The dynamic pressure test has been compared with the conventional aerosol test at different leakage levels. The results of this comparison show that the sensitivity of the dynamic pressure test is similar to that of the aerosol test. The pressure test, however, is independent of leak site and probe location and can be performed on respirators before and after their use.

  17. Intestinal infection following aerosol challenge of calves with Mycobacterium avium subspecies paratuberculosis

    PubMed Central

    2011-01-01

    A challenge experiment was performed to investigate whether administration of Mycobacterium avium subsp. paratuberculosis (MAP) via the respiratory route leads to MAP infection in calves. Eighteen calves from test negative dams were randomly allocated to four groups. Six calves were challenged with MAP nasally and six calves were challenged by transtracheal injection; three orally challenged calves served as positive controls, and three non challenged calves as negative controls. The challenge was performed as a nine-fold trickle dose, 107 CFU in total. Blood and faecal samples were collected frequently. Calves were euthanized three months post-challenge and extensively sampled. Blood samples were tested for the presence of antibodies and interferon gamma producing cells by ELISA. Faecal and tissue samples were cultured in a liquid culture system and the presence of MAP was confirmed by IS900 realtime PCR. Fourteen out of fifteen calves had no MAP antibody response. The negative controls remained negative; all positive controls became infected. Two nasally challenged calves showed a Purified Protein Derivative Avian (PPDA) specific interferon gamma response. In all nasally challenged calves, MAP positive intestinal samples were detected. In three calves of the nasal group MAP positive retropharyngeal lymph nodes or tonsils were detected. In all calves of the transtracheal group MAP positive intestinal tissues were detected as well and three had a MAP positive tracheobronchial lymph node. These findings indicate that inhalation of MAP aerosols can result in infection. These experimental results may be relevant for transmission under field conditions since viable MAP has been detected in dust on commercial dairy farms. PMID:22136728

  18. Determination of Antibiotic Efficacy against Bacillus anthracis in a Mouse Aerosol Challenge Model▿

    PubMed Central

    Heine, Henry S.; Bassett, Jennifer; Miller, Lynda; Hartings, Justin M.; Ivins, Bruce E.; Pitt, M. Louise; Fritz, David; Norris, Sarah L.; Byrne, W. Russell

    2007-01-01

    An anthrax spore aerosol infection mouse model was developed as a first test of in vivo efficacy of antibiotics identified as active against Bacillus anthracis. Whole-body, 50% lethal dose (LD50) aerosol challenge doses in a range of 1.9 × 103 to 3.4 × 104 CFU with spores of the fully virulent Ames strain were established for three inbred and one outbred mouse strain (A/J, BALB/c, C57BL, and Swiss Webster). The BALB/c strain was further developed as a model for antibiotic efficacy. Time course microbiological examinations of tissue burdens in mice after challenge showed that spores could remain dormant in the lungs while vegetative cells disseminated to the mediastinal lymph nodes and then to the spleen, accompanied by bacteremia. For antibiotic efficacy studies, BALB/c mice were challenged with 50 to 100 LD50 of spores followed by intraperitoneal injection of either ciprofloxacin at 30 mg/kg of body weight (every 12 h [q12h]) or doxycycline at 40 mg/kg (q6h). A control group was treated with phosphate-buffered saline (PBS) q6h. Treatment was begun 24 h after challenge with groups of 10 mice for 14 or 21 days. The PBS-treated control mice all succumbed (10/10) to inhalation anthrax infection within 72 h. Sixty-day survival rates for ciprofloxacin and doxycycline-treated groups were 8/10 and 9/10, respectively, for 14-day treatment and 10/10 and 7/10 for 21-day treatment. Delayed treatment with ciprofloxacin initiated 36 and 48 h postexposure resulted in 80% survival and was statistically no different than early (24 h) postexposure treatment. Results using this mouse model correlate closely with clinical observations of inhalational anthrax in humans and with earlier antibiotic studies in the nonhuman primate inhalational anthrax model. PMID:17296745

  19. An Aerosolized Brucella spp. Challenge Model for Laboratory Animals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To characterize the optimal aerosol dosage of Brucella abortus strain 2308 (S2308) and B. melitensis (S16M) in a laboratory animal model of brucellosis, dosages of 10**3 to 10**10 CFU were nebulized to mice. Although tissue weights were minimally influenced, total colony-forming units (CFU) per tis...

  20. Scientific Objectives, Measurement Needs, and Challenges Motivating the PARAGON Aerosol Initiative

    NASA Technical Reports Server (NTRS)

    Seinfeld, John H.; Kahn, Ralph A.; Anderson, Theodore L.; Charlson, Robert J.; Davies, Roger; Ogren, John A.; Diner, David J.; Schwartz, Stephen E.; Wielicki, Bruce A.

    2004-01-01

    Aerosols are involved in a complex set of processes that operate across many spatial and temporal scales. Understanding these processes, and ensuring their accurate representation in models of transport, radiation transfer, and climate, requires knowledge of aerosol physical, chemical, and optical properties and the distributions of these properties in space and time. To derive aerosol climate forcing, aerosol optical and microphysical properties and their spatial and temporal distributions, and aerosol interactions with clouds, need to be understood. Such data are also required in conjunction with size-resolved chemical composition in order to evaluate chemical transport models and to distinguish natural and anthropogenic forcing. Other basic parameters needed for modeling the radiative influences of aerosols are surface reflectivity and three-dimensional cloud fields. This large suite of parameters mandates an integrated observing and modeling system of commensurate scope. The Progressive Aerosol Retrieval and Assimilation Global Observing Network (PARAGON) concept, designed to meet this requirement, is motivated by the need to understand climate system sensitivity to changes in atmospheric constituents, to reduce climate model uncertainties, and to analyze diverse collections of data pertaining to aerosols. This paper highlights several challenges resulting from the complexity of the problem. Approaches for dealing with them are offered in the set of companion papers.

  1. Aerosol tests conducted at Aberdeen Proving Grounds MD.

    SciTech Connect

    Brockmann, John E.; Lucero, Daniel A.; Servantes, Brandon Lee; Hankins, Matthew Granholm

    2012-06-01

    Test data are reported that demonstrate the deposition from a spray dispersion system (Illinois Tool Works inductively charging rotary atomization nozzle) for application of decontamination solution to various surfaces in the passenger cabin of a Boeing 737 aircraft. The decontamination solution (EnviroTru) was tagged with a known concentration of fluorescein permitting determination of both airborne decontaminant concentration and surface deposited decontaminant solution so that the effective deposition rates and surface coverage could be determined and correlated with the amount of material sprayed. Six aerosol dispersion tests were conducted. In each test, aluminum foil deposition coupons were set out throughout the passenger area and the aerosol was dispersed. The aerosol concentration was measured with filter samplers as well as with optical techniques Average aerosol deposition ranged from 3 to 15 grams of decontamination solution per square meter. Some disagreement was observed between various instruments utilizing different measurement principles. These results demonstrate a potentially effective method to disperse decontaminant to interior surfaces of a passenger aircraft.

  2. Quantifying trace gas uptake to tropospheric aerosol: recent advances and remaining challenges.

    PubMed

    Abbatt, J P D; Lee, A K Y; Thornton, J A

    2012-10-07

    The interactions of trace gases with tropospheric aerosol can have significant effects on both gas phase and aerosol composition. In turn, this may affect the atmospheric oxidizing capacity, aerosol hygroscopicity and optical properties, and the lifetimes of trace aerosol species. Through the detailed description of specific reaction systems, this review article illustrates how detailed experimental studies of gas-particle interactions lead to both a comprehensive understanding of the underlying physical chemistry as well as accurate parameterizations for atmospheric modeling. The reaction systems studied illustrate the complexity in the field: (i) N(2)O(5) uptake, presented as a benchmark multiphase system, can lead to both NO(x) loss and halogen activation, (ii) loss of HO(2) on aqueous particles is surprisingly poorly studied given its potential importance for HO(x) loss, (iii) uptake of HNO(3) by marine aerosol and heterogeneous oxidation of organic-bearing particles are examples of how gas-particle interactions can lead to substantial alteration of aerosol composition, and (iv) the uptake of glyoxal to ammonium sulfate aerosol leads to highly complex particle-phase chemistry. In addition, for the first time, this article presents the challenges that must be addressed in the design and interpretation of atmospheric gas-to-particle uptake experiments.

  3. Interactions between biomass-burning aerosols and clouds over Southeast Asia: current status, challenges, and perspectives.

    PubMed

    Lin, Neng-Huei; Sayer, Andrew M; Wang, Sheng-Hsiang; Loftus, Adrian M; Hsiao, Ta-Chih; Sheu, Guey-Rong; Hsu, N Christina; Tsay, Si-Chee; Chantara, Somporn

    2014-12-01

    The interactions between aerosols, clouds, and precipitation remain among the largest sources of uncertainty in the Earth's energy budget. Biomass-burning aerosols are a key feature of the global aerosol system, with significant annually-repeating fires in several parts of the world, including Southeast Asia (SEA). SEA in particular provides a "natural laboratory" for these studies, as smoke travels from source regions downwind in which it is coupled to persistent stratocumulus decks. However, SEA has been under-exploited for these studies. This review summarizes previous related field campaigns in SEA, with a focus on the ongoing Seven South East Asian Studies (7-SEAS) and results from the most recent BASELInE deployment. Progress from remote sensing and modeling studies, along with the challenges faced for these studies, are also discussed. We suggest that improvements to our knowledge of these aerosol/cloud effects require the synergistic use of field measurements with remote sensing and modeling tools.

  4. Contaminated aerosol recovery from pulmonary function testing equipment.

    PubMed

    Hiebert, T; Miles, J; Okeson, G C

    1999-02-01

    Clinically, the spread of infectious agents between subjects undergoing spirometry is quite uncommon. There is almost no documentation in the medical literature on this subject. We studied the retrieval of nonpathogenic Escherichia coli after aerosolizing organisms into standard pulmonary function tubing of a type that is frequently used by volume-sensing spirometers. The arrival of the aerosol at the distal end of the tubing was documented by culture. After delays of 0, 1, 5, and 10 min, respectively, air was forcibly withdrawn from the proximal end of the tubing through a special petri plate assembly. The plates were cultured and the colonies were counted. Immediately after insufflation of organisms, air withdrawn from the proximal tubing had counts similar to the air sampled at the distal end. After a 1-min delay, the proximal samples contained only rare organisms. No organisms were recovered from proximal air samples after a delay of 5 or 10 min after insufflation of organisms. The absence of detectable aerosolized E. coli after delays of 5 and 10 min after insufflation of organisms into spirometry tubing supports the hypothesis that a significant transfer of aerosolized organisms does not occur during routine pulmonary function testing as long as an interval of 5 min or more is allowed between tests.

  5. Surrogate/spent fuel sabotage : aerosol ratio test program and Phase 2 test results.

    SciTech Connect

    Borek, Theodore Thaddeus III; Thompson, N. Slater; Sorenson, Ken Bryce; Hibbs, R.S.; Nolte, Oliver; Molecke, Martin Alan; Autrusson, Bruno; Young, F. I.; Koch, Wolfgang; Brochard, Didier; Pretzsch, Gunter Guido; Lange, Florentin

    2004-05-01

    A multinational test program is in progress to quantify the aerosol particulates produced when a high energy density device, HEDD, impacts surrogate material and actual spent fuel test rodlets. This program provides needed data that are relevant to some sabotage scenarios in relation to spent fuel transport and storage casks, and associated risk assessments; the program also provides significant political benefits in international cooperation. We are quantifying the spent fuel ratio, SFR, the ratio of the aerosol particles released from HEDD-impacted actual spent fuel to the aerosol particles produced from surrogate materials, measured under closely matched test conditions. In addition, we are measuring the amounts, nuclide content, size distribution of the released aerosol materials, and enhanced sorption of volatile fission product nuclides onto specific aerosol particle size fractions. These data are crucial for predicting radiological impacts. This document includes a thorough description of the test program, including the current, detailed test plan, concept and design, plus a description of all test components, and requirements for future components and related nuclear facility needs. It also serves as a program status report as of the end of FY 2003. All available test results, observations, and analyses - primarily for surrogate material Phase 2 tests using cerium oxide sintered ceramic pellets are included. This spent fuel sabotage - aerosol test program is coordinated with the international Working Group for Sabotage Concerns of Transport and Storage Casks, WGSTSC, and supported by both the U.S. Department of Energy and Nuclear Regulatory Commission.

  6. Efficiency tests of samplers for microbiological aerosols, a review

    NASA Technical Reports Server (NTRS)

    Henningson, E.; Faengmark, I.

    1984-01-01

    To obtain comparable results from studies using a variety of samplers of microbiological aerosols with different collection performances for various particle sizes, methods reported in the literature were surveyed, evaluated, and tabulated for testing the efficiency of the samplers. It is concluded that these samplers were not thoroughly tested, using reliable methods. Tests were conducted in static air chambers and in various outdoor and work environments. Results are not reliable as it is difficult to achieve stable and reproducible conditions in these test systems. Testing in a wind tunnel is recommended.

  7. SAM 2 balloon test (stratospheric aerosol measurement)

    NASA Technical Reports Server (NTRS)

    Pepin, T. J.

    1976-01-01

    As a parallel effort to the LACATE balloon experiment a small optical system was constructed to enable a balloon test of a diode filter system similar to the type planned for the Nimbus-G SAM II experiment. The system was called the SAM II Balloon Test. Results of the balloon flight are summarized.

  8. The Joint Aerosol-Monsoon Experiment: A New Challenge to Monsoon Climate Research

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.

    2008-01-01

    Aerosol and monsoon related droughts and floods are two of the most serious environmental hazards confronting more than 60% of the population of the world living in the Asian monsoon countries. In recent years, thanks to improved satellite and in-situ observations, and better models, great strides have been made in aerosol, and monsoon research respectively. There is now a growing body of evidence suggesting that interaction of aerosol forcing with water cycle dynamics in monsoon regions may substantially alter the redistribution of energy at the earth surface and in the atmosphere, and therefore significantly impact monsoon rainfall variability and long term trends. In this talk, I will describe issues related to societal needs, scientific background, and challenges in studies of aerosol-water cycle interaction in Asian monsoon regions. As a first step towards addressing these issues, the authors call for an integrated observation and modeling research approach aimed at the interactions between aerosol chemistry and radiative effects and monsoon dynamics of the coupled ocean-atmosphere-land system. A Joint Aerosol-Monsoon Experiment (JAMEX) is proposed for 2007-2011, with an enhanced observation period during 2008-09, encompassing diverse arrays of observations from surface, aircraft, unmanned aerial vehicles, and satellites of physical and chemical properties of aerosols, long range aerosol transport as well as meteorological and oceanographic parameters in the Indo-Pacific Asian monsoon region. JAMEX will leverage on coordination among many ongoing and planned national programs on aerosols and monsoon research in China, India, Japan, Nepal, Italy, US, as well as international research programs of the World Climate Research Program (WCRP) and the World Meteorological Organization (WMO).

  9. Aerosols

    Atmospheric Science Data Center

    2013-04-17

    ... article title:  Aerosols over Central and Eastern Europe     View Larger Image ... last weeks of March 2003, widespread aerosol pollution over Europe was detected by several satellite-borne instruments. The Multi-angle ...

  10. Aerosol-Water Cycle Interaction: A New Challenge in Monsoon Climate Research

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.

    2006-01-01

    Long recognized as a major environmental hazard, aerosol is now known to have strong impacts on both regional and global climate. It has been estimated that aerosol may reduce by up to 10% of the seasonal mean solar radiation reaching the earth surface, producing a global cooling effect that opposes global warming (Climate Change 2001). This means that the potential perils that humans have committed to global warming may be far greater than what we can detect at the present. As a key component of the Earth climate system, the water cycle is profoundly affected by the presence of aerosols in the atmosphere. Through the so-called direct effect , aerosol scatters and/or absorbs solar radiation, thus cooling the earth surface and changing the horizontal and vertical radiational heating contrast in the atmosphere. The heating contrast drives anomalous atmospheric circulation, resulting in changes in convection, clouds, and rainfall. Another way aerosol can affect the water cycle is through the so-called indirect effects, whereby aerosol increases the number of cloud condensation nuclei, prolongs life time of clouds, and inhibits the growth of cloud drops to raindrops. This leads to more clouds, and increased reflection of solar radiation, and further cooling at the earth surface. In monsoon regions, the response of the water cycle to aerosol forcing is especially complex, not only because of presence of diverse mix of aerosol species with vastly different radiative properties, but also because the monsoon is strongly influenced by ocean and land surface processes, land use, land change, as well as regional and global greenhouse warming effects. Thus, sorting out the impacts of aerosol forcing, and interaction with the monsoon water cycle is a very challenging problem. In this talk, I will offer some insights into how aerosols may impact the Asian monsoon based on preliminary results from satellite observations and climate model experiments. Specifically, I will discuss

  11. Aerosol-Water Cycle Interaction: A New Challenge in Monsoon Climate Research

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.

    2006-01-01

    Long recognized as a major environmental hazard, aerosol is now known to have strong impacts on both regional and global climate. It has been estimated that aerosol may reduce by up to 10% of the seasonal mean solar radiation reaching the earth surface, producing a global cooling effect that opposes global warming (Climate Change 2001). This means that the potential perils that humans have committed to global warming may be far greater than what we can detect at the present. As a key component of the Earth climate system, the water cycle is profoundly affected by the presence of aerosols in the atmosphere. Through the so-called "direct effect", aerosol scatters and/or absorbs solar radiation, thus cooling the earth surface and changing the horizontal and vertical radiational heating contrast in the atmosphere. The heating contrast drives anomalous atmospheric circulation, resulting in changes in convection, clouds, and rainfall. Another way aerosol can affect the water cycle is through the so-called "indirect effects", whereby aerosol increases the number of cloud condensation nuclei, prolongs life time of clouds, and inhibits the growth of cloud drops to raindrops. This leads to more clouds, and increased reflection of solar radiation, and further cooling at the earth surface. In monsoon regions, the response of the water cycle to aerosol forcing is especially complex, not only because of presence of diverse mix of aerosol species with vastly different radiative properties, but also because the monsoon is strongly influenced by ocean and land surface processes, land use, land change, as well as regional and global greenhouse warming effects. Thus, sorting out the impacts of aerosol forcing, and interaction with the monsoon water cycle is a very challenging problem. In this talk, I will offer some insights into how aerosols may impact the Asian monsoon based on preliminary results from satellite observations and climate model experiments. Specifically, I will

  12. An aerosol challenge model of tuberculosis in Mauritian cynomolgus macaques

    PubMed Central

    Sharpe, S. A.; White, A. D.; Sibley, L.; Gleeson, F.; Hall, G. A.; Basaraba, R. J.; McIntyre, A.; Clark, S. O.; Gooch, K.; Marsh, P. D.; Williams, A.; Dennis, M. J.

    2017-01-01

    Background New interventions for tuberculosis are urgently needed. Non-human primate (NHP) models provide the most relevant pre-clinical models of human disease and play a critical role in vaccine development. Models utilising Asian cynomolgus macaque populations are well established but the restricted genetic diversity of the Mauritian cynomolgus macaques may be of added value. Methods Mauritian cynomolgus macaques were exposed to a range of doses of M. tuberculosis delivered by aerosol, and the outcome was assessed using clinical, imaging and pathology-based measures. Results All macaques developed characteristic clinical signs and disease features of tuberculosis (TB). Disease burden and the ability to control disease were dependent on exposure dose. Mauritian cynomolgus macaques showed less variation in pulmonary disease burden and total gross pathology scores within exposure dose groups than either Indian rhesus macaques or Chinese cynomolgus macaques Conclusions The genetic homogeneity of Mauritian cynomolgus macaques makes them a potentially useful model of human tuberculosis. PMID:28273087

  13. Large-Scale Spray Releases: Additional Aerosol Test Results

    SciTech Connect

    Daniel, Richard C.; Gauglitz, Phillip A.; Burns, Carolyn A.; Fountain, Matthew S.; Shimskey, Rick W.; Billing, Justin M.; Bontha, Jagannadha R.; Kurath, Dean E.; Jenks, Jeromy WJ; MacFarlan, Paul J.; Mahoney, Lenna A.

    2013-08-01

    One of the events postulated in the hazard analysis for the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak event involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids that behave as a Newtonian fluid. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and in processing facilities across the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are mostly absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale testing. The small-scale testing and resultant data are described in Mahoney et al. (2012b), and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used

  14. Small-Scale Spray Releases: Additional Aerosol Test Results

    SciTech Connect

    Schonewill, Philip P.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, G. N.; Mahoney, Lenna A.; Tran, Diana N.; Burns, Carolyn A.; Kurath, Dean E.

    2013-08-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are largely absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale. The small-scale testing and resultant data are described in Mahoney et al. (2012b) and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used to mimic the

  15. Small-Scale Spray Releases: Initial Aerosol Test Results

    SciTech Connect

    Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

    2013-05-29

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and net generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of antifoam agents was assessed with most of the simulants. Orifices included round holes and

  16. Using global aerosol models and satellite data for air quality studies: Challenges and data needs

    NASA Technical Reports Server (NTRS)

    Chin, Mian

    2006-01-01

    Aerosol particles, also known as PM2.5 (particle diameter less than 2.5 pm) and PM10 (particle diameter less than 10 pm), are one of the key atmospheric components that determines air quality. Yet, air quality forecasts for PM are still in their infancy and remain a challenging task. It is difficult to simply relate PM levels to local meteorological conditions, and large uncertainties exist in regional air quality model emission inventories and initial and boundary conditions. Especially challenging are periods when a significant amount of aerosol comes from outside the regional modeling domain through long-range transport. In the past few years, NASA has launched several satellites with global aerosol measurement capabilities, providing large-scale chemical weather pictures. NASA has also supported development of global models which simulate atmospheric transport and transformation processes of important atmospheric gas and aerosol species. I will present the current modeling and satellite capabilities for PM2.5 studies, the possibilities and challenges in using satellite data for PM2.5 forecasts, and the needs of future remote sensing data for improving air quality monitoring and modeling.

  17. Small-Scale Spray Releases: Initial Aerosol Test Results

    SciTech Connect

    Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

    2012-11-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and

  18. Large-Scale Spray Releases: Initial Aerosol Test Results

    SciTech Connect

    Schonewill, Philip P.; Gauglitz, Phillip A.; Bontha, Jagannadha R.; Daniel, Richard C.; Kurath, Dean E.; Adkins, Harold E.; Billing, Justin M.; Burns, Carolyn A.; Davis, James M.; Enderlin, Carl W.; Fischer, Christopher M.; Jenks, Jeromy WJ; Lukins, Craig D.; MacFarlan, Paul J.; Shutthanandan, Janani I.; Smith, Dennese M.

    2012-12-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and

  19. Direct contact test for estimating the ecotoxicity of aerosol samples.

    PubMed

    Kováts, Nora; Acs, András; Kovács, Anikó; Ferincz, Arpád; Turóczi, Beatrix; Gelencsér, András

    2012-03-01

    Atmospheric particulate matter with aerodynamic diameter less than 10 μm (PM10) and 2.5 μm (PM2.5) is now identified as one of the most dangerous pollutants on human health by the EU new directive on air quality (2008/50/CE). Although these primary pollutants are monitored in cities, little information is available on their ecotoxicity. In this paper a 'whole-aerosol' testing protocol is suggested based on the kinetic version of the Vibrio fischeri bioluminescence inhibition test.

  20. Challenges of studying viral aerosol metagenomics and communities in comparison with bacterial and fungal aerosols.

    PubMed

    Prussin, Aaron J; Marr, Linsey C; Bibby, Kyle J

    2014-08-01

    Despite the obvious importance of viral transmission and ecology to medicine, epidemiology, ecology, agriculture, and microbiology, the study of viral bioaerosols and community structure has remained a vastly underexplored area, due to both unresolved technical challenges and unrecognized importance. High-throughput, culture-independent techniques such as viral metagenomics are beginning to revolutionize the study of viral ecology. With recent developments in viral metagenomics, characterization of viral bioaerosol communities provides an opportunity for high-impact future research. However, there remain significant challenges for the study of viral bioaerosols compared with viruses in other matrices, such as water, the human gut, and soil. Collecting enough biomass is essential for successful metagenomic analysis, but this is a challenge with viral bioaerosols. Herein, we provide a perspective on the importance of studying viral bioaerosols, the challenges of studying viral community structure, and the potential opportunities for improvements in methods to study viruses in indoor and outdoor air.

  1. Chimeric plantibody passively protects mice against aerosolized ricin challenge.

    PubMed

    Sully, Erin K; Whaley, Kevin J; Bohorova, Natasha; Bohorov, Ognian; Goodman, Charles; Kim, Do H; Pauly, Michael H; Velasco, Jesus; Hiatt, Ernie; Morton, Josh; Swope, Kelsi; Roy, Chad J; Zeitlin, Larry; Mantis, Nicholas J

    2014-05-01

    Recent incidents in the United States and abroad have heightened concerns about the use of ricin toxin as a bioterrorism agent. In this study, we produced, using a robust plant-based platform, four chimeric toxin-neutralizing monoclonal antibodies that were then evaluated for the ability to passively protect mice from a lethal-dose ricin challenge. The most effective antibody, c-PB10, was further evaluated in mice as a therapeutic following ricin exposure by injection and inhalation.

  2. Protection of MP-12-vaccinated rhesus macaques against parenteral and aerosol challenge with virulent rift valley fever virus.

    PubMed

    Morrill, John C; Peters, C J

    2011-07-15

    To test safety and efficacy of the Rift Valley fever MP-12 (RVF MP-12) vaccine, 9 healthy adult Rhesus macaques, weighing 5-10 kg, were inoculated intramuscularly with 6 × 10(3) plaque forming units (PFUs) of MP-12 vaccine. The monkeys developed neutralizing antibody responses with no adverse effects other than a transient, low-titer viremia in 3 monkeys. Four vaccinated animals challenged intravenously with 3 × 10(6) PFUs of virulent Rift Valley fever virus strain ZH-501 (RVFV ZH-501) at 126 days after vaccination were protected against infection. The remaining 5 vaccinated monkeys along with 2 monkeys that had been vaccinated 6 years prior were completely protected against a small particle aerosol challenge of 5 × 10(5) PFUs of RVFV ZH-501. The mutagen-attenuated RVF MP-12 vaccine was determined to be protective against intravenous and aerosol challenge with virulent RVFV in these macaques, which suggests further development as a vaccine for humans is warranted.

  3. Radiation Test Challenges for Scaled Commerical Memories

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.; Ladbury, Ray L.; Cohn, Lewis M.; Oldham, Timothy

    2007-01-01

    As sub-100nm CMOS technologies gather interest, the radiation effects performance of these technologies provide a significant challenge. In this talk, we shall discuss the radiation testing challenges as related to commercial memory devices. The focus will be on complex test and failure modes emerging in state-of-the-art Flash non-volatile memories (NVMs) and synchronous dynamic random access memories (SDRAMs), which are volatile. Due to their very high bit density, these device types are highly desirable for use in the natural space environment. In this presentation, we shall discuss these devices with emphasis on considerations for test and qualification methods required.

  4. Monoclonal Antibodies Passively Protect BALB/c Mice Against Burkholderia mallei Aerosol Challenge

    DTIC Science & Technology

    2006-03-01

    Infectious Diseases, 1425 Porter St., Fort Detrick, Frederick, MD 21702-5001. Phone: (301) 619-4893. Fax: (301) 619-2152. E -mail: david.waag@det.amedd.army.mil...negative control MAb ( E ) 18 h before an aerosol challenge with 20 LD50 of B. mallei strain China 7 (ATCC 23344) or challenged and then given per mouse 1... E ., S. Wong, D. E . Woods, D. A. B. Dance, and W. Chaowagul. 1994. Passive protection of diabetic rats with antisera specific for the poly

  5. Virus-Like Particle Vaccination Protects Nonhuman Primates from Lethal Aerosol Exposure with Marburgvirus (VLP Vaccination Protects Macaques against Aerosol Challenges).

    PubMed

    Dye, John M; Warfield, Kelly L; Wells, Jay B; Unfer, Robert C; Shulenin, Sergey; Vu, Hong; Nichols, Donald K; Aman, M Javad; Bavari, Sina

    2016-04-08

    Marburg virus (MARV) was the first filovirus to be identified following an outbreak of viral hemorrhagic fever disease in Marburg, Germany in 1967. Due to several factors inherent to filoviruses, they are considered a potential bioweapon that could be disseminated via an aerosol route. Previous studies demonstrated that MARV virus-like particles (VLPs) containing the glycoprotein (GP), matrix protein VP40 and nucleoprotein (NP) generated using a baculovirus/insect cell expression system could protect macaques from subcutaneous (SQ) challenge with multiple species of marburgviruses. In the current study, the protective efficacy of the MARV VLPs in conjunction with two different adjuvants: QS-21, a saponin derivative, and poly I:C against homologous aerosol challenge was assessed in cynomolgus macaques. Antibody responses against the GP antigen were equivalent in all groups receiving MARV VLPs irrespective of the adjuvant; adjuvant only-vaccinated macaques did not demonstrate appreciable antibody responses. All macaques were subsequently challenged with lethal doses of MARV via aerosol or SQ as a positive control. All MARV VLP-vaccinated macaques survived either aerosol or SQ challenge while animals administered adjuvant only exhibited clinical signs and lesions consistent with MARV disease and were euthanized after meeting the predetermined criteria. Therefore, MARV VLPs induce IgG antibodies recognizing MARV GP and VP40 and protect cynomolgus macaques from an otherwise lethal aerosol exposure with MARV.

  6. Why Is Improvement of Earth System Models So Elusive? Challenges and Strategies From Dust Aerosol Modeling

    NASA Astrophysics Data System (ADS)

    Miller, R. L.; Pérez García-Pando, C.; Perlwitz, J. P.; Ginoux, P. A.

    2015-12-01

    Past decades have seen an accelerating increase in computing efficiency,while climate models are representing a rapidly widening set ofphysical processes. Yet simulations of some fundamental aspects ofclimate like precipitation or aerosol forcing remain highly uncertainand resistent to progress. Dust aerosol modeling of soil particleslofted by wind erosion has seen a similar conflict between increasingmodel sophistication and remaining uncertainty. Dust aerosols perturbthe energy and water cycles by scattering radiation and acting as icenuclei, while mediating atmospheric chemistry and marinephotosynthesis (and thus the carbon cycle). These effects take placeacross scales from the dimensions of an ice crystal to theplanetary-scale circulation that disperses dust far downwind of itsparent soil. Representing this range leads to several modelingchallenges. Should we limit complexity in our model, which consumescomputer resources and inhibits interpretation? How do we decide if aprocess involving dust is worthy of inclusion within our model? Canwe identify a minimal representation of a complex process that isefficient yet retains the physics relevant to climate? Answeringthese questions about the appropriate degree of representation isguided by model evaluation, which presents several more challenges.How do we proceed if the available observations do not directlyconstrain our process of interest? (This could result from competingprocesses that influence the observed variable and obscure thesignature of our process of interest.) Examples will be presentedfrom dust modeling, with lessons that might be more broadlyapplicable. The end result will either be clinical depression or thereassuring promise of continued gainful employment as the communityconfronts these challenges.

  7. Measurements Of Sub- 3nm Aerosol Particles In Tropical Rainforest Conditions - Technical Challenges And Solutions

    NASA Astrophysics Data System (ADS)

    Wimmer, D.; Alessandro, F.; Backmann, J.; Manninen, H. E.; Lehtipalo, K.; Petäjä, T.; Kulmala, M. T.

    2014-12-01

    A Particle Size Magnifier (PSM; Vanhanen et al., 2011) was used for studying the sub-3 nm aerosol particles during the second intensive observation period of the GoAmazon campaign. The PSM is using diethylene glycol (DEG) as condensing liquid, which has a low saturation vapour pressure and is hygroscopic. The high supersaturation needed for activating sub-3 nm particles is reached by mixing the sample with clean air saturated with DEG. The measurements took place in Sept-Oct, when typical temperatures at the measurement site are around 303 K, and relative humidity (RH) around 90%. Due to these challenging conditions, in combination with the hygroscopicity of the DEG, careful design and testing of the instrument was required. We developed an inlet reducing the RH at the inlet of the PSM while keeping the diffusion losses of particles in the inlet as low as possible. The inlet design is based on a sintered tube, where dry, pressurized dilution flow is added. Downstream of the sintered tube, a core sampling probe is used. The core sampling allows to sample from the center of the tube, where the highest particle concentration is, while an additional make-up flow allows for a higher sample flow rate. The RH of the ambient, dilution flow and PSM inlet flow are monitored continuously. Tests in the laboratory have shown that the RH could be reduced down to less than 30%, while the ambient RH was 90-100%. The characterization of the inlet regarding diffusion losses lead to a cut off diameter of 1.6 nm, compared to 1.3 nm without inlet. Thus, this new inlet design allows measurements of sub-3 nm particles in tropical rainforest condition.

  8. Challenges to producing a long-term stratospheric aerosol climatology for chemistry and climate

    NASA Astrophysics Data System (ADS)

    Thomason, Larry; Vernier, Jean-Paul; Bourassa, Adam; Rieger, Landon; Luo, Beiping; Peter, Thomas; Arfeuille, Florian

    2016-04-01

    Stratospheric aerosol data sets are key inputs for climate models (GCMs, CCMs) particularly for understanding the role of volcanoes on climate and as a surrogate for understanding the potential of human-derived stratospheric aerosol as mitigation for global warming. In addition to supporting activities of individual climate models, the data sets also act as a historical input to the activities of SPARC's Chemistry-Climate Model Initiative (CCMI) and the World Climate Research Programme's Coupled Model Intercomparison Project (CMIP). One such data set was produced in 2004 as a part of the SPARC Assessment of Stratospheric Aerosol Properties (ASAP), extending from 1979 and 2004. It was primarily constructed from the Stratospheric Aerosol and Gas Experiment series of instruments but supplemented by data from other space-based sources and a number of ground-based and airborne instruments. Updates to this data set have expanded the timeframe to span from 1850 through 2014 through the inclusion of data from additional sources, such as photometer data and ice core analyses. Fundamentally, there are limitations to the reliability of the optical properties of aerosol inferred from even the most complete single instrument data sets. At the same time, the heterogeneous nature of the underlying data to this historical data set produces considerable challenges to the production of a climate data set which is both homogeneous and reliable throughout its timespan. In this presentation, we will discuss the impact of this heterogeneity showing specific examples such as the SAGE II to OSIRIS/CALIPSO transition in 2005. Potential solutions to these issues will also be discussed.

  9. In-place testing of tandem HEPA filter stages using fluorescent aerosols

    SciTech Connect

    Elder, J.C.; Kyle, T.G.; Tillery, M.I.; Ettinger, H.J.

    1980-01-01

    Fluorescent test aerosols were used in field testing of large multiple-stage HEPA filter systems. The technique excluded interference from non-fluorescent background particles known to leak into the plenum or ducting between the filters and the downstream sampling probe. This technique solved the problem of measuring extremely low concentrations of the test aerosol in the presence of background aerosol. The upstream fluorescent test aerosol was diluted with clean air and drawn into a single particle aerosol spectrometer capable of counting, sizing, and detecting fluorescence of each particle. The particle sizing function was performed on light scattered by the particle passing through the beam of a helium-cadmium laser. Concurrently the fluorescence excited by the laser illumination was detected at a longer wavelength. Since spectrometer response in the fluorescent mode was <2% of naturally occurring aerosols, background aerosols were insignificant as an interference to the downstream concentration measurement. Decontamination factors (DF) on the order of 10/sup 8/ were measured in the field studies on >9.4 m/sup 3//s (20,000 cfm) systems. Additional generator capacity and acceptably lower test aerosol to background aerosol concentraion ratios could be used to extend this capability to measure DF greater than 10/sup 8/. Dye-tagged DOP aerosols were generated either by gas-thermal or sonic nozzle generators. Experiments with the gas-thermal generator showed only 20% of fluorescence from the dye was degraded by the vaporization process. A single sonic nozzle was shown to aerosolize 0.7 to 1.0 L/h of dye-tagged DOP aerosol in the proper size range for HEPA filter testing. A multiple sonic nozzle generator is a practical consideration to provide greater capacity.

  10. Why Is Improvement of Earth System Models so Elusive? Challenges and Strategies from Dust Aerosol Modeling

    NASA Technical Reports Server (NTRS)

    Miller, Ronald L.; Garcia-Pando, Carlos Perez; Perlwitz, Jan; Ginoux, Paul

    2015-01-01

    Past decades have seen an accelerating increase in computing efficiency, while climate models are representing a rapidly widening set of physical processes. Yet simulations of some fundamental aspects of climate like precipitation or aerosol forcing remain highly uncertain and resistant to progress. Dust aerosol modeling of soil particles lofted by wind erosion has seen a similar conflict between increasing model sophistication and remaining uncertainty. Dust aerosols perturb the energy and water cycles by scattering radiation and acting as ice nuclei, while mediating atmospheric chemistry and marine photosynthesis (and thus the carbon cycle). These effects take place across scales from the dimensions of an ice crystal to the planetary-scale circulation that disperses dust far downwind of its parent soil. Representing this range leads to several modeling challenges. Should we limit complexity in our model, which consumes computer resources and inhibits interpretation? How do we decide if a process involving dust is worthy of inclusion within our model? Can we identify a minimal representation of a complex process that is efficient yet retains the physics relevant to climate? Answering these questions about the appropriate degree of representation is guided by model evaluation, which presents several more challenges. How do we proceed if the available observations do not directly constrain our process of interest? (This could result from competing processes that influence the observed variable and obscure the signature of our process of interest.) Examples will be presented from dust modeling, with lessons that might be more broadly applicable. The end result will either be clinical depression or there assuring promise of continued gainful employment as the community confronts these challenges.

  11. 1,5 iodonaphthyl Azide Inactivated V3526 Protects against Aerosol Challenge with Virulent Venezuelan Equine Encephalitis Virus.

    DTIC Science & Technology

    2016-06-02

    UNCLASSIFIED 2 Abstract: Venezuelan equine encephalitis virus (VEEV) is a New World alphavirus. There is no licensed vaccine for prophylaxis...against VEEV. VEEV is highly infectious in aerosolized form and has been identified as a bio-terrorism agent. The current IND vaccine is poorly...V3526 may be explored further for specific development as an effective vaccine candidate against aerosol challenge of virulent VEEV. Highlights

  12. [Testing of vaccines. The challenge of testing complex combination vaccines].

    PubMed

    Merkle, A; Lechner, H; Oppling, V; Meyer, H

    2014-10-01

    Vaccines are biologicals. This group of medicinal products is produced with a predefined variability based on the biological starting materials used. Vaccines are subject to official control authority batch release performed by the Paul-Ehrlich-Institut (PEI). To release batches to the market, experimental testing has to be conducted by an official medicines control laboratory as the PEI. It is the aim of this independent testing to demonstrate the conformity of quality criteria with conditions set in the marketing authorization for each lot produced. The testing is performed on the basis of vaccine specific batch release guideline and due to the difficult and time consuming testing procedures often run in parallel with manufacturers testing. If test results comply with the predefined criteria, the lot in question is released. This article describes the challenge of official control authority batch release testing of two complex combination vaccines.

  13. Reconstruction of the Tambora forcing with global aerosol models : Challenges and limitations

    NASA Astrophysics Data System (ADS)

    Khodri, Myriam; Zanchettin, Davide; Timmreck, Claudia

    2016-04-01

    climate models had been subject to a common experimental protocol for the 1815 Tambora eruption in order to assess the uncertainties in the derived volcanic forcing. Results indicate substantial differences among model regarding key aerosols optical properties for the Tambora eruption. In this contribution we will discuss current uncertainties regarding relevant microphysical processes possibly underlining these large differences and challenges for current global stratospheric aerosol models to derive consensual forcing for large tropical volcanic eruptions.

  14. MEMS performance challenges: packaging and shock tests

    NASA Astrophysics Data System (ADS)

    Chang, Jiyoung; Yang, Chen; Zhang, Bin; Lin, Liwei

    2011-06-01

    This paper describes recent advances in the MEMS performance challenges with emphases on packaging and shock tests. In the packaging area, metal to metal bonding processes have been developed to overcome limitations of the glass frit bonding by means of two specific methods: (1) pre-reflow of solder for enhanced bonding adhesion, and (2) the insertion of thin metal layer between parent metal bonding materials. In the shock test area, multiscale analysis for a MEMS package system has been developed with experimental verifications to investigate dynamic responses under drop-shock tests. Structural deformation and stress distribution data are extracted and predicted for device fracture and in-operation stiction analyses for micro mechanical components in various MEMS sensors, including accelerometers and gyroscopes.

  15. Developments of aerosol retrieval algorithm for Geostationary Environmental Monitoring Spectrometer (GEMS) and the retrieval accuracy test

    NASA Astrophysics Data System (ADS)

    KIM, M.; Kim, J.; Jeong, U.; Ahn, C.; Bhartia, P. K.; Torres, O.

    2013-12-01

    A scanning UV-Visible spectrometer, the GEMS (Geostationary Environment Monitoring Spectrometer) onboard the GEO-KOMPSAT2B (Geostationary Korea Multi-Purpose Satellite) is planned to be launched in geostationary orbit in 2018. The GEMS employs hyper-spectral imaging with 0.6 nm resolution to observe solar backscatter radiation in the UV and Visible range. In the UV range, the low surface contribution to the backscattered radiation and strong interaction between aerosol absorption and molecular scattering can be advantageous in retrieving aerosol optical properties such as aerosol optical depth (AOD) and single scattering albedo (SSA). By taking the advantage, the OMI UV aerosol algorithm has provided information on the absorbing aerosol (Torres et al., 2007; Ahn et al., 2008). This study presents a UV-VIS algorithm to retrieve AOD and SSA from GEMS. The algorithm is based on the general inversion method, which uses pre-calculated look-up table with assumed aerosol properties and measurement condition. To obtain the retrieval accuracy, the error of the look-up table method occurred by the interpolation of pre-calculated radiances is estimated by using the reference dataset, and the uncertainties about aerosol type and height are evaluated. Also, the GEMS aerosol algorithm is tested with measured normalized radiance from OMI, a provisional data set for GEMS measurement, and the results are compared with the values from AERONET measurements over Asia. Additionally, the method for simultaneous retrieve of the AOD and aerosol height is discussed.

  16. Hair Testing for Drugs - Challenges for Interpretation.

    PubMed

    Stout, P R

    2007-07-01

    While testing hair for drugs of abuse has become more widely used in the past 30 years, significant challenges still remain to the interpretation of the results from these tests. Of primary concern is the likelihood of unwitting contamination from the environment producing a result indicative of drug use. It is imperative that this possibility be controlled and understood so that results from hair testing can be appropriately interpreted. Presently, truly unique metabolites are needed for many drugs (THC-COOH being a notable exception) since the mechanisms of decontamination processes used for hair are still poorly understood. While there is evidence that many drugs preferentially bind to melanin and that darker hair contains more drug, it is unclear how this translates into the interpretation of results for a population. Cosmetic treatments likely reduce the amount of drug systemically incorporated into hair and thus present a challenge of inappropriately negative interpretation. In addition, hair damaged as a result of cosmetic treatment may be at increased risk for environmental contamination. The asynchronous nature of human hair growth can also complicate results by obscuring the timeline of drug deposition. Lastly, the analytical variation of quantitative values has been demonstrated by several proficiency testing systems throughout the world to be high and method specific. Thus, while hair testing may be able to provide information about exposure to drugs, it is difficult at present to obtain reproducible results that can be unquestionably related to drug ingestion or to infer that the absence of drug in a hair sample is positive proof of no drug usage. Many questions still remain to be addressed by mechanistic understanding of drug deposition and retention in hair.

  17. Natural History of Francisella tularensis in Aerosol-Challenged BALB/c Mice

    PubMed Central

    Chuvala, Lara; Riggins, Renaldo; Cirz, Ryan; Cass, Robert; Louie, Arnold; Drusano, G. L.

    2016-01-01

    The objective of this study was to evaluate the natural history and pathogenesis of Francisella tularensis in a murine model of inhalational tularemia with the SchuS4 strain. Before the efficacy of antimicrobials could be assessed in this model, further model development was required to determine the optimal time to start therapy. This study helped define the time course of infection after aerosol challenge by quantifying the presence of bacteria in lung, blood, and spleen at multiple harvest points. In this study, mice were infected via a targeted inhaled dose of 100 50% lethal doses (LD50s) (LD50 = 300 CFU) of F. tularensis by whole-body aerosol. At 1, 24, 36, 48, 60, 72, 75, 78, 81, 84, 87, and 90 h postchallenge, groups of 15 animals were sacrificed and blood, lung, and splenic tissue samples were harvested, homogenized, plated, and incubated to evaluate the bacterial load in those tissues. It was determined that of the 3 sample types harvested, splenic tissue provided the most consistent bacterial counts, which steadily increased with the progressing infection. Further, it was determined that lung samples from all (15/15) animals were positive for infection at 75 h postaerosolization and that 14/15 animals had positive splenic tissue counts. Bacterial levels in blood were not predictive of treatment initiation. For future therapeutic evaluation studies in this model using F. tularensis (SchuS4), it was determined that therapy should be initiated at 75 h postchallenge and validated by spleen involvement. PMID:26824958

  18. Natural History of Francisella tularensis in Aerosol-Challenged BALB/c Mice.

    PubMed

    Heine, Henry S; Chuvala, Lara; Riggins, Renaldo; Cirz, Ryan; Cass, Robert; Louie, Arnold; Drusano, G L

    2016-01-11

    The objective of this study was to evaluate the natural history and pathogenesis of Francisella tularensis in a murine model of inhalational tularemia with the SchuS4 strain. Before the efficacy of antimicrobials could be assessed in this model, further model development was required to determine the optimal time to start therapy. This study helped define the time course of infection after aerosol challenge by quantifying the presence of bacteria in lung, blood, and spleen at multiple harvest points. In this study, mice were infected via a targeted inhaled dose of 100 50% lethal doses (LD50s) (LD50 = 300 CFU) of F. tularensis by whole-body aerosol. At 1, 24, 36, 48, 60, 72, 75, 78, 81, 84, 87, and 90 h postchallenge, groups of 15 animals were sacrificed and blood, lung, and splenic tissue samples were harvested, homogenized, plated, and incubated to evaluate the bacterial load in those tissues. It was determined that of the 3 sample types harvested, splenic tissue provided the most consistent bacterial counts, which steadily increased with the progressing infection. Further, it was determined that lung samples from all (15/15) animals were positive for infection at 75 h postaerosolization and that 14/15 animals had positive splenic tissue counts. Bacterial levels in blood were not predictive of treatment initiation. For future therapeutic evaluation studies in this model using F. tularensis (SchuS4), it was determined that therapy should be initiated at 75 h postchallenge and validated by spleen involvement.

  19. The X-33 Flight Test Challenge

    NASA Technical Reports Server (NTRS)

    Borden, David; Ramiscal, Ermin; Howell, John

    1999-01-01

    Low cost access to space has eluded present launch system technologies. Our objective is to reduce the cost of putting a payload into space from $10,000 per pound to $1000 per pound. In July 1996, a cooperative agreement was initiated between the Lockheed Martin Skunk Works and NASA to help accomplish this goal. The X-33 is the first step in the process to make low cost space access a reality. The X-33 is a suborbital, hypersonic lifting body, proof of concept of a reusable launch vehicle. The X-33 flight test program will validate technologies such as a metallic thermal protection system, Linear Aerospike Engines, use of tanks and struts as fundamental structural elements, as well as quick turnaround time. Flight testing will begin in July 2000, with launches originating from Edwards Air Force Base and initial landings at Michael Army Airfield in Utah. Data collected from these flight tests will aid in the decision to build an economically viable single stage to orbit reusable launch vehicle. This paper will explore the technical challenges facing the X-33 Flight Test Team.

  20. Stimulation of interferons and endorphins/enkephalins by electro-aerosol inhalation? An experimental approach for testing an expanded hypothesis

    NASA Astrophysics Data System (ADS)

    Wehner, A. P.

    1984-03-01

    The biological effects of endorphins/enkephalins and of interferons closely resemble those attributed to air ions and electro-aerosols. Air ions/electro-aerosols have been reported to affect brain functions and feelings of “well-being”; to have sedative and analgesic effects; to be therapeutically effective in certain viral (e.g., upper respiratory) infections; and to have tumor-attenuating effects. It is, therefore, conceivable that endorphins/enkephalins and interferons might be the mediators of these air ion/electro-aerosol effects. An experimental approach for testing this hypothesis is described. It calls for mice to be challenged with a suitable agent and to be exposed under appropriate conditions to a negatively charged aerosol of physiological saline 6 hours/day for up to 3 weeks; for the serial sacrifice of subgroups of these mice; for collecting blood and brains of the sacrificed animals; for the bioassay of the sera for interferon; and for radioimmunoassays of brains for endorphins/enkephalins. Special considerations, necessitated by the nature of the experiment, are discussed.

  1. Spent fuel sabotage aerosol ratio program : FY 2004 test and data summary.

    SciTech Connect

    Brucher, Wenzel; Koch, Wolfgang; Pretzsch, Gunter Guido; Loiseau, Olivier; Mo, Tin; Billone, Michael C.; Autrusson, Bruno A.; Young, F. I.; Coats, Richard Lee; Burtseva, Tatiana; Luna, Robert Earl; Dickey, Roy R.; Sorenson, Ken Bryce; Nolte, Oliver; Thompson, Nancy Slater; Hibbs, Russell S.; Gregson, Michael Warren; Lange, Florentin; Molecke, Martin Alan; Tsai, Han-Chung

    2005-07-01

    This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program has been underway for several years. This program provides data that are relevant to some sabotage scenarios in relation to spent fuel transport and storage casks, and associated risk assessments. The program also provides significant technical and political benefits in international cooperation. We are quantifying the Spent Fuel Ratio (SFR), the ratio of the aerosol particles released from HEDD-impacted actual spent fuel to the aerosol particles produced from surrogate materials, measured under closely matched test conditions, in a contained test chamber. In addition, we are measuring the amounts, nuclide content, size distribution of the released aerosol materials, and enhanced sorption of volatile fission product nuclides onto specific aerosol particle size fractions. These data are the input for follow-on modeling studies to quantify respirable hazards, associated radiological risk assessments, vulnerability assessments, and potential cask physical protection design modifications. This document includes an updated description of the test program and test components for all work and plans made, or revised, during FY 2004. It also serves as a program status report as of the end of FY 2004. All available test results, observations, and aerosol analyses plus interpretations--primarily for surrogate material Phase 2 tests, series 2/5A through 2/9B, using cerium oxide sintered ceramic pellets are included. Advanced plans and progress are described for upcoming tests with unirradiated, depleted uranium oxide and actual spent fuel test rodlets. This spent fuel sabotage--aerosol test program is coordinated with the international Working Group for Sabotage Concerns of

  2. Laboratory Testing of Aerosol for Enclosure Air Sealing

    SciTech Connect

    Harrington, Curtis; Modera, Mark

    2012-05-01

    This report presents a process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage.

  3. Influenza A Virus Challenge Models in Cynomolgus Macaques Using the Authentic Inhaled Aerosol and Intra-Nasal Routes of Infection

    PubMed Central

    Marriott, Anthony C.; Dennis, Mike; Kane, Jennifer A.; Gooch, Karen E.; Hatch, Graham; Sharpe, Sally; Prevosto, Claudia; Leeming, Gail; Zekeng, Elsa-Gayle; Staples, Karl J.; Hall, Graham; Ryan, Kathryn A.; Bate, Simon; Moyo, Nathifa; Whittaker, Catherine J.; Hallis, Bassam; Silman, Nigel J.; Lalvani, Ajit; Wilkinson, Tom M.; Hiscox, Julian A.; Stewart, James P.; Carroll, Miles W.

    2016-01-01

    Non-human primates are the animals closest to humans for use in influenza A virus challenge studies, in terms of their phylogenetic relatedness, physiology and immune systems. Previous studies have shown that cynomolgus macaques (Macaca fascicularis) are permissive for infection with H1N1pdm influenza virus. These studies have typically used combined challenge routes, with the majority being intra-tracheal delivery, and high doses of virus (> 107 infectious units). This paper describes the outcome of novel challenge routes (inhaled aerosol, intra-nasal instillation) and low to moderate doses (103 to 106 plaque forming units) of H1N1pdm virus in cynomolgus macaques. Evidence of virus replication and sero-conversion were detected in all four challenge groups, although the disease was sub-clinical. Intra-nasal challenge led to an infection confined to the nasal cavity. A low dose (103 plaque forming units) did not lead to detectable infectious virus shedding, but a 1000-fold higher dose led to virus shedding in all intra-nasal challenged animals. In contrast, aerosol and intra-tracheal challenge routes led to infections throughout the respiratory tract, although shedding from the nasal cavity was less reproducible between animals compared to the high-dose intra-nasal challenge group. Intra-tracheal and aerosol challenges induced a transient lymphopaenia, similar to that observed in influenza-infected humans, and greater virus-specific cellular immune responses in the blood were observed in these groups in comparison to the intra-nasal challenge groups. Activation of lung macrophages and innate immune response genes was detected at days 5 to 7 post-challenge. The kinetics of infection, both virological and immunological, were broadly in line with human influenza A virus infections. These more authentic infection models will be valuable in the determination of anti-influenza efficacy of novel entities against less severe (and thus more common) influenza infections. PMID

  4. Influenza A Virus Challenge Models in Cynomolgus Macaques Using the Authentic Inhaled Aerosol and Intra-Nasal Routes of Infection.

    PubMed

    Marriott, Anthony C; Dennis, Mike; Kane, Jennifer A; Gooch, Karen E; Hatch, Graham; Sharpe, Sally; Prevosto, Claudia; Leeming, Gail; Zekeng, Elsa-Gayle; Staples, Karl J; Hall, Graham; Ryan, Kathryn A; Bate, Simon; Moyo, Nathifa; Whittaker, Catherine J; Hallis, Bassam; Silman, Nigel J; Lalvani, Ajit; Wilkinson, Tom M; Hiscox, Julian A; Stewart, James P; Carroll, Miles W

    2016-01-01

    Non-human primates are the animals closest to humans for use in influenza A virus challenge studies, in terms of their phylogenetic relatedness, physiology and immune systems. Previous studies have shown that cynomolgus macaques (Macaca fascicularis) are permissive for infection with H1N1pdm influenza virus. These studies have typically used combined challenge routes, with the majority being intra-tracheal delivery, and high doses of virus (> 107 infectious units). This paper describes the outcome of novel challenge routes (inhaled aerosol, intra-nasal instillation) and low to moderate doses (103 to 106 plaque forming units) of H1N1pdm virus in cynomolgus macaques. Evidence of virus replication and sero-conversion were detected in all four challenge groups, although the disease was sub-clinical. Intra-nasal challenge led to an infection confined to the nasal cavity. A low dose (103 plaque forming units) did not lead to detectable infectious virus shedding, but a 1000-fold higher dose led to virus shedding in all intra-nasal challenged animals. In contrast, aerosol and intra-tracheal challenge routes led to infections throughout the respiratory tract, although shedding from the nasal cavity was less reproducible between animals compared to the high-dose intra-nasal challenge group. Intra-tracheal and aerosol challenges induced a transient lymphopaenia, similar to that observed in influenza-infected humans, and greater virus-specific cellular immune responses in the blood were observed in these groups in comparison to the intra-nasal challenge groups. Activation of lung macrophages and innate immune response genes was detected at days 5 to 7 post-challenge. The kinetics of infection, both virological and immunological, were broadly in line with human influenza A virus infections. These more authentic infection models will be valuable in the determination of anti-influenza efficacy of novel entities against less severe (and thus more common) influenza infections.

  5. Experience and Challenges in Implementing Stratospheric Aerosol Gas Experiment on Meteor-3M Platform

    NASA Technical Reports Server (NTRS)

    Habib, Shahid; Newsom, Jerry; Rawls, Richard

    2001-01-01

    Implementation of Stratospheric Aerosol Gas Experiment (SAGE) is a joint science mission between the Rosavioskosmos, also called Russian Aviation and Space Agency (RASA) and the National Aeronautics and Space Administration (NASA). Under the global collaboration agreement established by President Clinton and Yeltsin in 1995 between the United States and Russia, space was one of the major areas identified for joint scientific collaboration. There were several collaborative projects identified under space, earth, human exploration of space and aeronautics. SAGE was one of the key Earth Science instruments selected common to both countries' interests in ozone research. SAGE has a long space heritage, and four earlier versions of this instrument have flown in space for the last 15-year period. It has provided a vital ozone and aerosol data in the mid latitudes and has contributed in the overall ozone depletion research. SAGE II, the fourth instrument has been flying in space on NASA's Earth Radiation Budget Satellite (ERBS) for the last 14 years. Ball Aerospace built the instrument under Langley Research Center's (LaRC) management. SAGE III for Russian Meteor-3M mission is a third generation design with more spectral bands, elaborate data gathering and storage and intelligent terrestrial software. The Russian collaboration required a complete integration of SAGE III on the Russian Meteor-3M satellite and a launch on a Zenit-2 launch vehicle manufactured in Ukraine. The whole complex is scheduled to be launched from Baikonur cosmodrome in early 2001. This cooperative mission has presented a number of management, technical and logistical challenges on both sides. This paper makes an attempt to review and document such experiences.

  6. Development and testing of an aerosol-stratus cloud parameterization scheme for middle and high latitudes

    SciTech Connect

    Olsson, P.Q.; Meyers, M.P.; Kreidenweis, S.; Cotton, W.R.

    1996-04-01

    The aim of this new project is to develop an aerosol/cloud microphysics parameterization of mixed-phase stratus and boundary layer clouds. Our approach is to create, test, and implement a bulk-microphysics/aerosol model using data from Atmospheric Radiation Measurement (ARM) Cloud and Radiation Testbed (CART) sites and large-eddy simulation (LES) explicit bin-resolving aerosol/microphysics models. The primary objectives of this work are twofold. First, we need the prediction of number concentrations of activated aerosol which are transferred to the droplet spectrum, so that the aerosol population directly affects the cloud formation and microphysics. Second, we plan to couple the aerosol model to the gas and aqueous-chemistry module that will drive the aerosol formation and growth. We begin by exploring the feasibility of performing cloud-resolving simulations of Arctic stratus clouds over the North Slope CART site. These simulations using Colorado State University`s regional atmospheric modeling system (RAMS) will be useful in designing the structure of the cloud-resolving model and in interpreting data acquired at the North Slope site.

  7. Laboratory Testing of Aerosol for Enclosure Air Sealing

    SciTech Connect

    Harrington, C.; Modera, M.

    2012-05-01

    Space conditioning energy use can be significantly reduced by addressing uncontrolled infiltration and exfiltration through the envelope of a building. A process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology is presented. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage.

  8. Biological Aerosol Test Method and Personal Protective Equipment (PPE) Decon

    DTIC Science & Technology

    2011-05-01

    technologies for disinfecting filtering facepiece respirators (FFRs) by aerosolizing, sampling, and analyzing viability of A/H5N1 virus on FFRs...personal respiratory protective devices. A component of that effort was to conduct a study of technologies for disinfecting filtering facepiece...flat-fold/three-panel, surgical , N95 respirator that is designed to resist splash and splatter of bodily fluids and infectious materials. These masks

  9. Surrogate/spent fuel sabotage aerosol ratio testing:phase 1 summary and results.

    SciTech Connect

    Vigil, Manuel Gilbert; Sorenson, Ken Bryce; Lange, F. , Germany); Nolte, O. (Fraunhofer Institut fur Toxikologie und Experimentelle Medizin, Germany); Koch, W. (Fraunhofer Institut fur Toxikologie und Experimentelle Medizin, Germany); Dickey, Roy R.; Yoshimura, Richard Hiroyuki; Molecke, Martin Alan; Autrusson, Bruno (Institut de Radioprotection et de Surete Nucleaire , France); Young, F. I.; Pretzsch, Gunter Guido (Gesellschaft fur Anlagen- und reaktorsicherheit , Germany)

    2005-10-01

    This multinational test program is quantifying the aerosol particulates produced when a high energy density device (HEDD) impacts surrogate material and actual spent fuel test rodlets. The experimental work, performed in four consecutive test phases, has been in progress for several years. The overall program provides needed data that are relevant to some sabotage scenarios in relation to spent fuel transport and storage casks, and associated risk assessments. This program also provides significant political benefits in international cooperation for nuclear security related evaluations. The spent fuel sabotage--aerosol test program is coordinated with the international Working Group for Sabotage Concerns of Transport and Storage Casks (WGSTSC), and supported by both the U.S. Department of Energy and Nuclear Regulatory Commission. This report summarizes the preliminary, Phase 1 work performed in 2001 and 2002 at Sandia National Laboratories and the Fraunhofer Institute, Germany, and documents the experimental results obtained, observations, and preliminary interpretations. Phase 1 testing included: performance quantifications of the HEDD devices; characterization of the HEDD or conical shaped charge (CSC) jet properties with multiple tests; refinement of the aerosol particle collection apparatus being used; and, CSC jet-aerosol tests using leaded glass plates and glass pellets, serving as representative brittle materials. Phase 1 testing was quite important for the design and performance of the following Phase 2 test program and test apparatus.

  10. Aerosol vaccination with AERAS-402 elicits robust cellular immune responses in the lungs of rhesus macaques but fails to protect against high-dose Mycobacterium tuberculosis challenge.

    PubMed

    Darrah, Patricia A; Bolton, Diane L; Lackner, Andrew A; Kaushal, Deepak; Aye, Pyone Pyone; Mehra, Smriti; Blanchard, James L; Didier, Peter J; Roy, Chad J; Rao, Srinivas S; Hokey, David A; Scanga, Charles A; Sizemore, Donata R; Sadoff, Jerald C; Roederer, Mario; Seder, Robert A

    2014-08-15

    Development of a vaccine against pulmonary tuberculosis may require immunization strategies that induce a high frequency of Ag-specific CD4 and CD8 T cells in the lung. The nonhuman primate model is essential for testing such approaches because it has predictive value for how vaccines elicit responses in humans. In this study, we used an aerosol vaccination strategy to administer AERAS-402, a replication-defective recombinant adenovirus (rAd) type 35 expressing Mycobacterium tuberculosis Ags Ag85A, Ag85B, and TB10.4, in bacillus Calmette-Guérin (BCG)-primed or unprimed rhesus macaques. Immunization with BCG generated low purified protein derivative-specific CD4 T cell responses in blood and bronchoalveolar lavage. In contrast, aerosolized AERAS-402 alone or following BCG induced potent and stable Ag85A/b-specific CD4 and CD8 effector T cells in bronchoalveolar lavage that largely produced IFN-γ, as well as TNF and IL-2. Such responses induced by BCG, AERAS-402, or both failed to confer overall protection following challenge with 275 CFUs M. tuberculosis Erdman, although vaccine-induced responses associated with reduced pathology were observed in some animals. Anamnestic T cell responses to Ag85A/b were not detected in blood of immunized animals after challenge. Overall, our data suggest that a high M. tuberculosis challenge dose may be a critical factor in limiting vaccine efficacy in this model. However, the ability of aerosol rAd immunization to generate potent cellular immunity in the lung suggests that using different or more immunogens, alternative rAd serotypes with enhanced immunogenicity, and a physiological challenge dose may achieve protection against M. tuberculosis.

  11. Evaluation of eight bioaerosol samplers challenged with aerosols of free bacteria.

    PubMed

    Jensen, P A; Todd, W F; Davis, G N; Scarpino, P V

    1992-10-01

    The need to quantify airborne microorganisms in the commercial microbiology industry (biotechnology) and during evaluations of indoor air quality, infectious disease outbreaks, and agriculture health investigations has shown there is a major technological void in bioaerosol sampling techniques to measure and identify viable and nonviable aerosols. As commercialization of microbiology increases and diversifies, it is increasingly necessary to assess occupational exposure to bioaerosols. Meaningful exposure estimates, by using area or environmental samplers, can only be ensured by the generation of data that are both precise and accurate. The Andersen six-stage viable (microbial) particle sizing sampler (6-STG) and the Ace Glass all-glass impinger-30 (AGI-30) have been suggested as the samplers of choice for the collection of viable microorganisms by the International Aerobiology Symposium and the American Conference of Governmental Industrial Hygienists. Some researchers consider these samplers inconvenient for evaluating industrial bioprocesses and indoor or outdoor environments. Alternative samplers for the collection of bioaerosols are available; however, limited information has been reported on their collection efficiencies. A study of the relative sampling efficiencies of eight bioaerosol samplers has been completed. Eight samplers were individually challenged with a bioaerosol, created with a Collison nebulizer, of either Bacillus subtilis or Escherichia coli. The samplers were evaluated under controlled conditions in a horizontal bioaerosol chamber. During each experimental run, simultaneous samples were collected with a reference AGI-30 to verify the concentration of microorganisms in the chamber from run to run and day to day.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. A CpG oligonucleotide can protect mice from a low aerosol challenge dose of Burkholderia mallei.

    PubMed

    Waag, David M; McCluskie, Michael J; Zhang, Ningli; Krieg, Arthur M

    2006-03-01

    Treatment with an oligodeoxynucleotide (ODN) containing CPG motifs (CpG ODN 7909) was found to protect BALB/c mice from lung infection or death after aerosol challenge with Burkholderia mallei. Protection was associated with enhanced levels of gamma interferon (IFN-gamma)-inducible protein 10, interleukin-12 (IL-12), IFN-gamma, and IL-6. Preexposure therapy with CpG ODNs may protect victims of a biological attack from glanders.

  13. Liquid rocket engine test facility engineering challenges

    NASA Astrophysics Data System (ADS)

    Ellerbrock, Hartwig; Ziegenhagen, Stefan

    2006-12-01

    Liquid rocket engines for launch vehicles and space crafts as well as their subsystems need to be verified and qualified during hot-runs. A high test cadence combined with a flexible test team helps to reduce the cost for test verification during development/qualification as well as during acceptance testing for production. Test facility intelligence allows to test subsystems in the same manner as during complete engine system tests and will therefore reduce development time and cost. This paper gives an overview of the maturing of test engineering know how for rocket engine test stands as well as high altitude test stands for small propulsion thrusters at EADS-ST in Ottobrunn and Lampoldshausen and is split into two parts: Part 1 gives a historical overview of the EADS-ST test stands at Ottobrunn and Lampoldshausen since the beginning of Rocket propulsion activities in the 1960s. Part 2 gives an overview of the actual test capabilities and the test engineering know-how for test stand construction/adaptation and their use during running programs. Examples of actual realised facility concepts are given to demonstrate cost saving potential for test programs in both cases for development/qualification issues as well as for production purposes.

  14. Aerosol Filter Loading Data for a Simulated Jet Engine Test Cell Aerosol.

    DTIC Science & Technology

    1979-08-01

    media. M SECTION II TEST PROGRAM I. TESTING PROCEDURE Sheets of the filter media were obtained from Owens - Corning Fiberglas Corporation. Ten centimeter...loading cycle. 2. TEST FILTERS The four following glass fiber filter medias were obtained from Owens - Corning Fiberglas Corporation (OCF) and tested both...shown in Table 22. Filters were washed from the back side. 5. ONCLUSIONS Four glass fiber filters, specified in the contract, were obtained from Owens

  15. Large Liquid Rocket Testing: Strategies and Challenges

    NASA Technical Reports Server (NTRS)

    Rahman, Shamim A.; Hebert, Bartt J.

    2005-01-01

    Rocket propulsion development is enabled by rigorous ground testing in order to mitigate the propulsion systems risks that are inherent in space flight. This is true for virtually all propulsive devices of a space vehicle including liquid and solid rocket propulsion, chemical and non-chemical propulsion, boost stage and in-space propulsion and so forth. In particular, large liquid rocket propulsion development and testing over the past five decades of human and robotic space flight has involved a combination of component-level testing and engine-level testing to first demonstrate that the propulsion devices were designed to meet the specified requirements for the Earth to Orbit launchers that they powered. This was followed by a vigorous test campaign to demonstrate the designed propulsion articles over the required operational envelope, and over robust margins, such that a sufficiently reliable propulsion system is delivered prior to first flight. It is possible that hundreds of tests, and on the order of a hundred thousand test seconds, are needed to achieve a high-reliability, flight-ready, liquid rocket engine system. This paper overviews aspects of earlier and recent experience of liquid rocket propulsion testing at NASA Stennis Space Center, where full scale flight engines and flight stages, as well as a significant amount of development testing has taken place in the past decade. The liquid rocket testing experience discussed includes testing of engine components (gas generators, preburners, thrust chambers, pumps, powerheads), as well as engine systems and complete stages. The number of tests, accumulated test seconds, and years of test stand occupancy needed to meet varying test objectives, will be selectively discussed and compared for the wide variety of ground test work that has been conducted at Stennis for subscale and full scale liquid rocket devices. Since rocket propulsion is a crucial long-lead element of any space system acquisition or

  16. Unique Challenges Testing SDRs for Space

    NASA Technical Reports Server (NTRS)

    Chelmins, David; Downey, Joseph A.; Johnson, Sandra K.; Nappier, Jennifer M.

    2013-01-01

    This paper describes the approach used by the Space Communication and Navigation (SCaN) Testbed team to qualify three Software Defined Radios (SDR) for operation in space and the characterization of the platform to enable upgrades on-orbit. The three SDRs represent a significant portion of the new technologies being studied on board the SCAN Testbed, which is operating on an external truss on the International Space Station (ISS). The SCaN Testbed provides experimenters an opportunity to develop and demonstrate experimental waveforms and applications for communication, networking, and navigation concepts and advance the understanding of developing and operating SDRs in space. Qualifying a Software Defined Radio for the space environment requires additional consideration versus a hardware radio. Tests that incorporate characterization of the platform to provide information necessary for future waveforms, which might exercise extended capabilities of the hardware, are needed. The development life cycle for the radio follows the software development life cycle, where changes can be incorporated at various stages of development and test. It also enables flexibility to be added with minor additional effort. Although this provides tremendous advantages, managing the complexity inherent in a software implementation requires a testing beyond the traditional hardware radio test plan. Due to schedule and resource limitations and parallel development activities, the subsystem testing of the SDRs at the vendor sites was primarily limited to typical fixed transceiver type of testing. NASA s Glenn Research Center (GRC) was responsible for the integration and testing of the SDRs into the SCaN Testbed system and conducting the investigation of the SDR to advance the technology to be accepted by missions. This paper will describe the unique tests that were conducted at both the subsystem and system level, including environmental testing, and present results. For example, test

  17. Unique Challenges Testing SDRs for Space

    NASA Technical Reports Server (NTRS)

    Johnson, Sandra; Chelmins, David; Downey, Joseph; Nappier, Jennifer

    2013-01-01

    This paper describes the approach used by the Space Communication and Navigation (SCaN) Testbed team to qualify three Software Defined Radios (SDR) for operation in space and the characterization of the platform to enable upgrades on-orbit. The three SDRs represent a significant portion of the new technologies being studied on board the SCAN Testbed, which is operating on an external truss on the International Space Station (ISS). The SCaN Testbed provides experimenters an opportunity to develop and demonstrate experimental waveforms and applications for communication, networking, and navigation concepts and advance the understanding of developing and operating SDRs in space. Qualifying a Software Defined Radio for the space environment requires additional consideration versus a hardware radio. Tests that incorporate characterization of the platform to provide information necessary for future waveforms, which might exercise extended capabilities of the hardware, are needed. The development life cycle for the radio follows the software development life cycle, where changes can be incorporated at various stages of development and test. It also enables flexibility to be added with minor additional effort. Although this provides tremendous advantages, managing the complexity inherent in a software implementation requires a testing beyond the traditional hardware radio test plan. Due to schedule and resource limitations and parallel development activities, the subsystem testing of the SDRs at the vendor sites was primarily limited to typical fixed transceiver type of testing. NASA's Glenn Research Center (GRC) was responsible for the integration and testing of the SDRs into the SCaN Testbed system and conducting the investigation of the SDR to advance the technology to be accepted by missions. This paper will describe the unique tests that were conducted at both the subsystem and system level, including environmental testing, and present results. For example, test

  18. 40 CFR 53.59 - Aerosol transport test for Class I equivalent method samplers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... air flow splitting components that may be used in a Class I candidate equivalent method sampler such... candidate samplers in which the aerosol flow path (the flow path through which sample air passes upstream of... through which sample air is flowing during performance of this test. (3) A no-flow filter is a...

  19. 40 CFR 53.59 - Aerosol transport test for Class I equivalent method samplers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... air flow splitting components that may be used in a Class I candidate equivalent method sampler such... candidate samplers in which the aerosol flow path (the flow path through which sample air passes upstream of... through which sample air is flowing during performance of this test. (3) A no-flow filter is a...

  20. 40 CFR 53.59 - Aerosol transport test for Class I equivalent method samplers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... air flow splitting components that may be used in a Class I candidate equivalent method sampler such... candidate samplers in which the aerosol flow path (the flow path through which sample air passes upstream of... through which sample air is flowing during performance of this test. (3) A no-flow filter is a...

  1. CO, O3, and aerosol measurements from NASA Global Tropospheric Experiment - Test flights 1981

    NASA Astrophysics Data System (ADS)

    Hinton, R. R.; Browell, E. V.; Gregory, G. L.; Harriss, R. C.

    1982-05-01

    A series of four instrument test flights was conducted during July 1981 in preparation for the NASA Global Tropospheric Experiment. The purpose of the flights was to demonstrate the feasibility and value of simultaneously measuring several specific atmospheric pollutants over a 25 deg latitudinal range. Carbon monoxide and methane grab samples were obtained simultaneously with nearly continuous in situ ozone and remote ozone and aerosol optical radar measurements. The sampling platform was a NASA Electra, a four engine turboprop aircraft. Attention is given to CO and CH4 sample collection and analysis, ozone measurement methods, the aerosol measurement method, an interpretation of the optical radar display, and a synergistic consideration of results.

  2. Spent fuel sabotage test program, characterization of aerosol dispersal : interim final report.

    SciTech Connect

    Gregson, Michael Warren; Brockmann, John E.; Loiseau, Olivier; Klennert, Lindsay A.; Nolte, Oliver; Molecke, Martin Alan; Autrusson, Bruno A.; Koch, Wolfgang; Pretzsch, Gunter Guido; Brucher, Wenzel; Steyskal, Michele D.

    2008-03-01

    This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program provides source-term data that are relevant to plausible sabotage scenarios in relation to spent fuel transport and storage casks and associated risk assessments. We present details and significant results obtained from this program from 2001 through 2007. Measured aerosol results include: respirable fractions produced; amounts, nuclide content, and produced particle size distributions and morphology; measurements of volatile fission product species enhanced sorption--enrichment factors onto respirable particles; and, status on determination of the spent fuel ratio, SFR, needed for scaling studies. Emphasis is provided on recent Phase 3 tests using depleted uranium oxide pellets plus non-radioactive fission product dopants in surrogate spent fuel test rodlets, plus the latest surrogate cerium oxide results and aerosol laboratory supporting calibration work. The DUO{sub 2}, CeO{sub 2}, plus fission product dopant aerosol particle results are compared with available historical data. We also provide a status review on continuing preparations for the final Phase 4 in this program, tests using individual short rodlets containing actual spent fuel from U.S. PWR reactors, with both high- and lower-burnup fuel. The source-term data, aerosol results, and program design have been tailored to support and guide follow-on computer modeling of aerosol dispersal hazards and radiological consequence assessments. This spent fuel sabotage, aerosol test program was performed primarily at Sandia National Laboratories, with support provided by both the U.S. Department of Energy and the Nuclear Regulatory Commission. This program has significant input from, and is cooperatively

  3. Spent fuel sabotage test program, characterization of aerosol dispersal : technical review and analysis supplement.

    SciTech Connect

    Durbin, Samuel G.; Lindgren, Eric Richard

    2009-07-01

    This project seeks to provide vital data required to assess the consequences of a terrorist attack on a spent fuel transportation cask. One such attack scenario involves the use of conical shaped charges (CSC), which are capable of damaging a spent fuel transportation cask. In the event of such an attack, the amount of radioactivity that may be released as respirable aerosols is not known with great certainty. Research to date has focused on measuring the aerosol release from single short surrogate fuel rodlets subjected to attack by a small CSC device in various aerosol chamber designs. The last series of three experiments tested surrogate fuel rodlets made with depleted uranium oxide ceramic pellets in a specially designed double chamber aerosol containment apparatus. This robust testing apparatus was designed to prevent any radioactive release and allow high level radioactive waste disposal of the entire apparatus following testing of actual spent fuel rodlets as proposed. DOE and Sandia reviews of the project to date identified a number of issues. The purpose of this supplemental report is to address and document the DOE review comments and to resolve the issues identified in the Sandia technical review.

  4. Open-Ended Test Items Pose Challenges

    ERIC Educational Resources Information Center

    Sawchuk, Stephen

    2010-01-01

    Most experts in the testing community have presumed that the $350 million promised by the U.S. Department of Education to support common assessments would promote those that made greater use of open-ended items capable of measuring higher-order critical-thinking skills. But as measurement experts consider the multitude of possibilities for an…

  5. Hall Effect Thruster Ground Testing Challenges

    DTIC Science & Technology

    2009-08-18

    high purity propellent to eliminate the risk of oxidation poisoning the thermionically emitting electron/neutralizer source drive the entire Hall effect...Mason, L., Jankovsky, R., Snyder, J. S., Malone , S., Haas, J., and Gallimore, A. D., “Spacecraft Interaction Test Results for the High Performance

  6. Genetic testing for melanoma predisposition: current challenges.

    PubMed

    Gerstenblith, Meg R; Goldstein, Alisa M; Tucker, Margaret A; Fraser, Mary C

    2007-01-01

    A complex interaction of genetic, host, and environmental factors results in cutaneous malignant melanoma, the fifth most common cancer among men and the sixth among women in the United States. Mortality rates for cutaneous malignant melanoma depend on stage at diagnosis; thus, efforts are aimed at early detection and identification of risk factors for melanoma to distinguish those individuals requiring close surveillance. Melanoma susceptibility genes CDKN2A and CDK4 play a role in the development of melanoma, especially among some familial melanoma kindreds. The functions of CDKN2A and CDK4 in melanoma development, however, are currently incompletely understood. Therefore, at this time, predictive genetic testing for CDKN2A mutations outside of defined research protocols is not recommended because of the low likelihood of detecting mutations even in high-risk groups, the present inadequacy of interpreting a test result due to variations in penetrance and unclear associations with other cancers, and the minimal influence knowledge of mutation status currently has on medical management. Oncology nurses have an important role in identifying individuals at high risk for melanoma regardless of CDKN2A mutation status, encouraging enrollment in skin surveillance programs, and providing patient education regarding sun protection, prevention and early detection of melanoma.

  7. Challenges in constraining anthropogenic aerosol effects on cloud radiative forcing using present-day spatiotemporal variability.

    PubMed

    Ghan, Steven; Wang, Minghuai; Zhang, Shipeng; Ferrachat, Sylvaine; Gettelman, Andrew; Griesfeller, Jan; Kipling, Zak; Lohmann, Ulrike; Morrison, Hugh; Neubauer, David; Partridge, Daniel G; Stier, Philip; Takemura, Toshihiko; Wang, Hailong; Zhang, Kai

    2016-05-24

    A large number of processes are involved in the chain from emissions of aerosol precursor gases and primary particles to impacts on cloud radiative forcing. Those processes are manifest in a number of relationships that can be expressed as factors dlnX/dlnY driving aerosol effects on cloud radiative forcing. These factors include the relationships between cloud condensation nuclei (CCN) concentration and emissions, droplet number and CCN concentration, cloud fraction and droplet number, cloud optical depth and droplet number, and cloud radiative forcing and cloud optical depth. The relationship between cloud optical depth and droplet number can be further decomposed into the sum of two terms involving the relationship of droplet effective radius and cloud liquid water path with droplet number. These relationships can be constrained using observations of recent spatial and temporal variability of these quantities. However, we are most interested in the radiative forcing since the preindustrial era. Because few relevant measurements are available from that era, relationships from recent variability have been assumed to be applicable to the preindustrial to present-day change. Our analysis of Aerosol Comparisons between Observations and Models (AeroCom) model simulations suggests that estimates of relationships from recent variability are poor constraints on relationships from anthropogenic change for some terms, with even the sign of some relationships differing in many regions. Proxies connecting recent spatial/temporal variability to anthropogenic change, or sustained measurements in regions where emissions have changed, are needed to constrain estimates of anthropogenic aerosol impacts on cloud radiative forcing.

  8. SEMI-VOLATILE SECONDARY AEROSOLS IN URBAN ATMOSPHERES: MEETING A MEASURED CHALLENGE

    EPA Science Inventory

    This presentation compares the results from various particle measurement methods as they relate to semi-volatile secondary aerosols in urban atmospheres. The methods include the PM2.5 Federal Reference Method; Particle Concentrator - BYU Organic Sampling System (PC-BOSS); the Re...

  9. Live Attenuated Mutants of Francisella tularensis Protect Rabbits against Aerosol Challenge with a Virulent Type A Strain

    PubMed Central

    Smith, Le'Kneitah P.; Cole, Kelly Stefano; Santiago, Araceli E.; Mann, Barbara J.; Barry, Eileen M.

    2014-01-01

    Francisella tularensis, a Gram-negative bacterium, is the causative agent of tularemia. No licensed vaccine is currently available for protection against tularemia, although an attenuated strain, dubbed the live vaccine strain (LVS), is given to at-risk laboratory personnel as an investigational new drug (IND). In an effort to develop a vaccine that offers better protection, recombinant attenuated derivatives of a virulent type A strain, SCHU S4, were evaluated in New Zealand White (NZW) rabbits. Rabbits vaccinated via scarification with the three attenuated derivatives (SCHU S4 ΔguaBA, ΔaroD, and ΔfipB strains) or with LVS developed a mild fever, but no weight loss was detected. Twenty-one days after vaccination, all vaccinated rabbits were seropositive for IgG to F. tularensis lipopolysaccharide (LPS). Thirty days after vaccination, all rabbits were challenged with aerosolized SCHU S4 at doses ranging from 50 to 500 50% lethal doses (LD50). All rabbits developed fevers and weight loss after challenge, but the severity was greater for mock-vaccinated rabbits. The ΔguaBA and ΔaroD SCHU S4 derivatives provided partial protection against death (27 to 36%) and a prolonged time to death compared to results for the mock-vaccinated group. In contrast, LVS and the ΔfipB strain both prolonged the time to death, but there were no survivors from the challenge. This is the first demonstration of vaccine efficacy against aerosol challenge with virulent type A F. tularensis in a species other than a rodent since the original work with LVS in the 1960s. The ΔguaBA and ΔaroD SCHU S4 derivatives warrant further evaluation and consideration as potential vaccines for tularemia and for identification of immunological correlates of protection. PMID:24614653

  10. Challenges in constraining anthropogenic aerosol effects on cloud radiative forcing using present-day spatiotemporal variability

    PubMed Central

    Ghan, Steven; Wang, Minghuai; Zhang, Shipeng; Ferrachat, Sylvaine; Gettelman, Andrew; Griesfeller, Jan; Kipling, Zak; Lohmann, Ulrike; Morrison, Hugh; Neubauer, David; Partridge, Daniel G.; Stier, Philip; Takemura, Toshihiko; Wang, Hailong; Zhang, Kai

    2016-01-01

    A large number of processes are involved in the chain from emissions of aerosol precursor gases and primary particles to impacts on cloud radiative forcing. Those processes are manifest in a number of relationships that can be expressed as factors dlnX/dlnY driving aerosol effects on cloud radiative forcing. These factors include the relationships between cloud condensation nuclei (CCN) concentration and emissions, droplet number and CCN concentration, cloud fraction and droplet number, cloud optical depth and droplet number, and cloud radiative forcing and cloud optical depth. The relationship between cloud optical depth and droplet number can be further decomposed into the sum of two terms involving the relationship of droplet effective radius and cloud liquid water path with droplet number. These relationships can be constrained using observations of recent spatial and temporal variability of these quantities. However, we are most interested in the radiative forcing since the preindustrial era. Because few relevant measurements are available from that era, relationships from recent variability have been assumed to be applicable to the preindustrial to present-day change. Our analysis of Aerosol Comparisons between Observations and Models (AeroCom) model simulations suggests that estimates of relationships from recent variability are poor constraints on relationships from anthropogenic change for some terms, with even the sign of some relationships differing in many regions. Proxies connecting recent spatial/temporal variability to anthropogenic change, or sustained measurements in regions where emissions have changed, are needed to constrain estimates of anthropogenic aerosol impacts on cloud radiative forcing. PMID:26921324

  11. A comparison of controlled negative pressure and aerosol quantitative respirator fit test systems by using fixed leaks.

    PubMed

    Crutchfield, C D; Murphy, R W; Van Ert, M D

    1991-06-01

    An automated version of a new method for quantitative respirator fit testing by controlled negative pressure was compared with a computerized aerosol fit test system. The controlled negative pressure technique eliminates many of the problems associated with aerosol and pressure decay fit test methods. A series of fixed leaks was used to compare the leak measurement capabilities of the controlled negative pressure system against a standard computerized aerosol fit test system. Negative pressure and aerosol fit factors determined for a series of fixed leaks through hypodermic needles were highly correlated with each other (r = 0.998) and with the cross-sectional areas of the leak needles (r greater than 0.995).

  12. Overview of the Capstone depleted uranium study of aerosols from impact with armored vehicles: test setup and aerosol generation, characterization, and application in assessing dose and risk.

    PubMed

    Parkhurst, Mary Ann; Guilmette, Raymond A

    2009-03-01

    The Capstone Depleted Uranium (DU) Aerosol Characterization and Risk Assessment Study was conducted to generate data about DU aerosols generated during the perforation of armored combat vehicles with large-caliber DU penetrators, and to apply the data in assessments of human health risks to personnel exposed to these aerosols, primarily through inhalation, during the 1991 Gulf War or in future military operations. The Capstone study consisted of two components: 1) generating, sampling, and characterizing DU aerosols by firing at and perforating combat vehicles, and 2) applying the source-term quantities and characteristics of the aerosols to the evaluation of doses and risks. This paper reviews the background of the study including the bases for the study, previous reviews of DU particles and health assessments from DU used by the U.S. military, the objectives of the study components, the participants and oversight teams, and the types of exposures it was intended to evaluate. It then discusses exposure scenarios used in the dose and risk assessment and provides an overview of how the field tests and dose and risk assessments were conducted.

  13. Overview of the Capstone Depleted Uranium Study of Aerosols from Impact with Armored Vehicles: Test Setup and Aerosol Generation, Characterization, and Application in Assessing Dose and Risk

    SciTech Connect

    Parkhurst, MaryAnn; Guilmette, Raymond A.

    2009-03-01

    The Capstone Depleted Uranium (DU) Aerosol Characterization and Risk Assessment Study was conducted to generate data about DU aerosols generated during the perforation of armored combat vehicles with large-caliber DU penetrators, and to apply the data in assessments of human health risks to personnel exposed to these aerosols, primarily through inhalation, during the 1991 Gulf War or in future military operations. The Capstone study consisted of two components: 1) generating, sampling and characterizing DU aerosols by firing at and perforating combat vehicles and 2) applying the source-term quantities and characteristics of the aerosols to the evaluation of doses and risks. This paper reviews the background of the study including the bases for the study, previous reviews of DU particles and health assessments from DU used by the U.S. military, the objectives of the study components, the participants and oversight teams, and the types of exposures it was intended to evaluate. It then discusses exposure scenarios used in the dose and risk assessment and provides an overview of how the field tests and dose and risk assessments were conducted.

  14. Correlation of in vitro challenge testing with consumer use testing for cosmetic products.

    PubMed Central

    Brannan, D K; Dille, J C; Kaufman, D J

    1987-01-01

    An in vitro microbial challenge test has been developed to predict the likelihood of consumer contamination of cosmetic products. The challenge test involved inoculating product at four concentrations (30, 50, 70, and 100%) with microorganisms known to contaminate cosmetics. Elimination of these microorganisms at each concentration was followed over a 28-day period. The test was used to classify products as poorly preserved, marginally preserved, or well preserved. Consumer use testing was then used to determine whether the test predicted the risk of actual consumer contamination. Products classified by the challenge test as poorly preserved returned 46 to 90% contaminated after use. Products classified by the challenge test as well preserved returned with no contamination. Marginally preserved products returned with 0 to 21% of the used units contaminated. As a result, the challenge test described can be accurately used to predict the risk of consumer contamination of cosmetic products. PMID:3662517

  15. The MESSy aerosol submodel MADE3 (v2.0b): description and a box model test

    NASA Astrophysics Data System (ADS)

    Kaiser, J. C.; Hendricks, J.; Righi, M.; Riemer, N.; Zaveri, R. A.; Metzger, S.; Aquila, V.

    2014-01-01

    We introduce MADE3 (Modal Aerosol Dynamics model for Europe, adapted for global applications, 3rd generation), an aerosol dynamics submodel for application within the MESSy framework (Modular Earth Submodel System). MADE3 builds on the predecessor aerosol submodels MADE and MADE-in. Its main new features are the explicit representation of coarse particle interactions both with other particles and with condensable gases, and the inclusion of hydrochloric acid (HCl)/chloride (Cl) partitioning between the gas and condensed phases. The aerosol size distribution is represented in the new submodel as a superposition of nine lognormal modes: one for fully soluble particles, one for insoluble particles, and one for mixed particles in each of three size ranges (Aitken, accumulation, and coarse mode size ranges). In order to assess the performance of MADE3 we compare it to its predecessor MADE and to the much more detailed particle-resolved aerosol model PartMC-MOSAIC in a box model simulation of an idealised marine boundary layer test case. MADE3 and MADE results are very similar, except in the coarse mode, where the aerosol is dominated by sea spray particles. Cl is reduced in MADE3 with respect to MADE due to the HCl/Cl partitioning that leads to Cl removal from the sea spray aerosol in our test case. Additionally, aerosol nitrate concentration is higher in MADE3 due to the condensation of nitric acid on coarse particles. MADE3 and PartMC-MOSAIC show substantial differences in the fine particle size distributions (sizes ≲ 2 μm) that could be relevant when simulating climate effects on a global scale. Nevertheless, the agreement between MADE3 and PartMC-MOSAIC is very good when it comes to coarse particle size distribution, and also in terms of aerosol composition. Considering these results and the well-established ability of MADE in reproducing observed aerosol loadings and composition, MADE3 seems suitable for application within a global model.

  16. The Messy Aerosol Submodel MADE3 (v2.0b): Description and a Box Model Test

    NASA Technical Reports Server (NTRS)

    Kaiser, J. C.; Hendricks, J.; Righi, M.; Riemer, N.; Zaveri, R. A.; Metzger, S.; Aquila, Valentina

    2014-01-01

    We introduce MADE3 (Modal Aerosol Dynamics model for Europe, adapted for global applications, 3rd generation), an aerosol dynamics submodel for application within the MESSy framework (Modular Earth Submodel System). MADE3 builds on the predecessor aerosol submodels MADE and MADE-in. Its main new features are the explicit representation of coarse particle interactions both with other particles and with condensable gases, and the inclusion of hydrochloric acid (HCl)chloride (Cl) partitioning between the gas and condensed phases. The aerosol size distribution is represented in the new submodel as a superposition of nine lognormal modes: one for fully soluble particles, one for insoluble particles, and one for mixed particles in each of three size ranges (Aitken, accumulation, and coarse mode size ranges). In order to assess the performance of MADE3 we compare it to its predecessor MADE and to the much more detailed particle-resolved aerosol model PartMC-MOSAIC in a box model simulation of an idealized marine boundary layer test case. MADE3 and MADE results are very similar, except in the coarse mode, where the aerosol is dominated by sea spray particles. Cl is reduced in MADE3 with respect to MADE due to the HClCl partitioning that leads to Cl removal from the sea spray aerosol in our test case. Additionally, aerosol nitrate concentration is higher in MADE3 due to the condensation of nitric acid on coarse particles. MADE3 and PartMC- MOSAIC show substantial differences in the fine particle size distributions (sizes about 2 micrometers) that could be relevant when simulating climate effects on a global scale. Nevertheless, the agreement between MADE3 and PartMC-MOSAIC is very good when it comes to coarse particle size distribution, and also in terms of aerosol composition. Considering these results and the well-established ability of MADE in reproducing observed aerosol loadings and composition, MADE3 seems suitable for application within a global model.

  17. Strain-dependent CNS dissemination in guinea pigs after Mycobacterium tuberculosis aerosol challenge.

    PubMed

    Be, Nicholas A; Klinkenberg, Lee G; Bishai, William R; Karakousis, Petros C; Jain, Sanjay K

    2011-09-01

    Clinical reports suggest an association of distinct Mycobacterium tuberculosis strains with CNS disease. We therefore examined CNS dissemination by different laboratory strains (two M. tuberculosis H37Rv, one CDC1551) in a guinea pig aerosol infection model. Although all strains grew exponentially in lungs, with similar bacterial burdens at the time of extrapulmonary dissemination, M. tuberculosis CDC1551 disseminated to the CNS significantly more than the H37Rv strains. No CNS lesions were observed throughout the study, with only a modest cytokine response. These data suggest that M. tuberculosis may have virulence factors that promote CNS dissemination, distinct from those required for pulmonary TB.

  18. Efficacy and immunogenicity of single-dose AdVAV intranasal anthrax vaccine compared to anthrax vaccine absorbed in an aerosolized spore rabbit challenge model.

    PubMed

    Krishnan, Vyjayanthi; Andersen, Bo H; Shoemaker, Christine; Sivko, Gloria S; Tordoff, Kevin P; Stark, Gregory V; Zhang, Jianfeng; Feng, Tsungwei; Duchars, Matthew; Roberts, M Scot

    2015-04-01

    AdVAV is a replication-deficient adenovirus type 5-vectored vaccine expressing the 83-kDa protective antigen (PA83) from Bacillus anthracis that is being developed for the prevention of disease caused by inhalation of aerosolized B. anthracis spores. A noninferiority study comparing the efficacy of AdVAV to the currently licensed Anthrax Vaccine Absorbed (AVA; BioThrax) was performed in New Zealand White rabbits using postchallenge survival as the study endpoint (20% noninferiority margin for survival). Three groups of 32 rabbits were vaccinated with a single intranasal dose of AdVAV (7.5 × 10(7), 1.5 × 10(9), or 3.5 × 10(10) viral particles). Three additional groups of 32 animals received two doses of either intranasal AdVAV (3.5 × 10(10) viral particles) or intramuscular AVA (diluted 1:16 or 1:64) 28 days apart. The placebo group of 16 rabbits received a single intranasal dose of AdVAV formulation buffer. All animals were challenged via the inhalation route with a targeted dose of 200 times the 50% lethal dose (LD50) of aerosolized B. anthracis Ames spores 70 days after the initial vaccination and were followed for 3 weeks. PA83 immunogenicity was evaluated by validated toxin neutralizing antibody and serum anti-PA83 IgG enzyme-linked immunosorbent assays (ELISAs). All animals in the placebo cohort died from the challenge. Three of the four AdVAV dose cohorts tested, including two single-dose cohorts, achieved statistical noninferiority relative to the AVA comparator group, with survival rates between 97% and 100%. Vaccination with AdVAV also produced antibody titers with earlier onset and greater persistence than vaccination with AVA.

  19. Drug-Free Schools: A National Challenge. Drug Testing.

    ERIC Educational Resources Information Center

    The ERIC Review, 1990

    1990-01-01

    "The ERIC Review" announces research results, publications, and new programs relevant to each issue's theme topic. This inaugural issue contains two principal articles: "Drug-Free Schools: A National Challenge," by Samuel Y. Fustukjian, and "Drug Testing," by Amy Klauke and Margaret Hadderman. In addition, the following major features concerned…

  20. Diffusive deposition of aerosols in Phebus containment during FPT-2 test

    SciTech Connect

    Kontautas, A.; Urbonavicius, E.

    2012-07-01

    At present the lumped-parameter codes is the main tool to investigate the complex response of the containment of Nuclear Power Plant in case of an accident. Continuous development and validation of the codes is required to perform realistic investigation of the processes that determine the possible source term of radioactive products to the environment. Validation of the codes is based on the comparison of the calculated results with the measurements performed in experimental facilities. The most extensive experimental program to investigate fission product release from the molten fuel, transport through the cooling circuit and deposition in the containment is performed in PHEBUS test facility. Test FPT-2 performed in this facility is considered for analysis of processes taking place in containment. Earlier performed investigations using COCOSYS code showed that the code could be successfully used for analysis of thermal-hydraulic processes and deposition of aerosols, but there was also noticed that diffusive deposition on the vertical walls does not fit well with the measured results. In the CPA module of ASTEC code there is implemented different model for diffusive deposition, therefore the PHEBUS containment model was transferred from COCOSYS code to ASTEC-CPA to investigate the influence of the diffusive deposition modelling. Analysis was performed using PHEBUS containment model of 16 nodes. The calculated thermal-hydraulic parameters are in good agreement with measured results, which gives basis for realistic simulation of aerosol transport and deposition processes. Performed investigations showed that diffusive deposition model has influence on the aerosol deposition distribution on different surfaces in the test facility. (authors)

  1. Performance of High Flow Rate Personal Respirable Samplers When Challenged with Mineral Aerosols of Different Particle Size Distributions

    PubMed Central

    Stacey, Peter; Thorpe, Andrew; Echt, Alan

    2016-01-01

    It is thought that the performance of respirable samplers may vary when exposed to dust aerosols with different particle sizes and wind speeds. This study investigated the performance of the GK 4.16 (RASCAL), GK 2.69, PPI 8, and FSP 10, high flow rate personal samplers when exposed to aerosols of mineral dust in a wind tunnel at two different wind speeds (1 and 2 m s−1) and orientations (towards and side-on to the source of emission). The mass median aerodynamic diameter of four aerosolized test dusts ranged from 8 to 25 µm with geometric standard deviations from 1.6 to 2 µm. The performance of each sampler type was compared with that of the SIMPEDS (Higgins–Dewell design) sampler. There was slight evidence to suggest that the performance of the FSP 10 is affected by the direction of the inlet relative to the air flow, although this was not significant when most respirable dust concentrations were compared, possibly due to the variability of paired dust concentration results. The GK 2.69, RASCAL, and PPI 8 samplers had similar performances, although the results when side-on to the emission source were generally slightly lower than the SIMPEDS. Despite slight differences between respirable dust concentrations the respirable crystalline silica values were not significantly different from the SIMPEDS. The GK family of cyclones obtained most precise results and more closely matched the SIMPEDS. A comparison with dust concentration results from previous calm air chamber studies (where wind speeds were < 0.4 m s−1) found that the relative performance between samplers was similar to those observed in this work indicating consistent performance relative to the SIMPEDS in both calm and moving air. PMID:26865560

  2. Improvement of the CULTEX(®) exposure technology by radial distribution of the test aerosol.

    PubMed

    Aufderheide, Michaela; Heller, Wolf-Dieter; Krischenowski, Olaf; Möhle, Niklas; Hochrainer, Dieter

    2017-03-02

    The exposure of cellular based systems cultivated on microporous membranes at the air-liquid interface (ALI) has been accepted as an appropriate approach to simulate the exposure of cells of the respiratory tract to native airborne substances. The efficiency of such an exposure procedure with regard to stability and reproducibility depends on the optimal design at the interface between the cellular test system and the exposure technique. The actual exposure systems favor the dynamic guidance of the airborne substances to the surface of the cells in specially designed exposure devices. Two module types, based on a linear or radial feed of the test atmosphere to the test system, were used for these studies. In our technical history, the development started with the linear designed version, the CULTEX(®) glass modules, fulfilling basic requirements for running ALI exposure studies (Mohr and Durst, 2005). The instability in the distribution of different atmospheres to the cells caused us to create a new exposure module, characterized by a stable and reproducible radial guidance of the aerosol to the cells. The outcome was the CULTEX(®) RFS (Mohr et al., 2010). In this study, we describe the differences between the two systems with regard to particle distribution and deposition clarifying the advantages and disadvantages of a radial to a linear aerosol distribution concept.

  3. Current challenges and opportunities in nonclinical safety testing of biologics.

    PubMed

    Kronenberg, Sven; Baumann, Andreas; de Haan, Lolke; Hinton, Heather J; Moggs, Jonathan; Theil, Frank-Peter; Wakefield, Ian; Singer, Thomas

    2013-12-01

    Nonclinical safety testing of new biotherapeutic entities represents its own challenges and opportunities in drug development. Hot topics in this field have been discussed recently at the 2nd Annual BioSafe European General Membership Meeting. In this feature article, discussions on the challenges surrounding the use of PEGylated therapeutic proteins, selection of cynomolgus monkey as preclinical species, unexpected pharmacokinetics of biologics and the safety implications thereof are summarized. In addition, new developments in immunosafety testing of biologics, the use of transgenic mouse models and PK and safety implications of multispecific targeting approaches are discussed. Overall, the increasing complexity of new biologic modalities and formats warrants tailor-made nonclinical development strategies and experimental testing.

  4. HIV and Hepatitis Testing: Global Progress, Challenges, and Future Directions.

    PubMed

    Easterbrook, Philippa; Johnson, Cheryl; Figueroa, Carmen; Baggaley, Rachel

    2016-01-01

    HIV infection and viral hepatitis due to HBV and HCV infection are major causes of chronic disease worldwide, and share some common routes of transmission, epidemiology, initial barriers faced in treatment access, and in strategies for a global public health response. Testing and diagnosis of HIV, HBV, and HCV infection is the gateway for access to both care and treatment and prevention services, and crucial for an effective HIV and hepatitis epidemic response. In this review article, we first summarize the common goals and guiding principles in a public health approach to HIV and hepatitis testing. We summarize the impressive global progress in HIV testing scale-up and evolution of approaches, with expansion of provider-initiated testing and counseling in clinical settings (particularly antenatal and tuberculosis clinics), the introduction of more community based testing services, and use of rapid diagnostic tests enabling provision of same-day test results. However, 46% of all people living with HIV are still unaware of their serostatus, and many continue to be diagnosed and start antiretroviral therapy late. As testing and treatment scale-up accelerates for an "treat all" approach, other challenges to address include how to better focus testing and reach those yet undiagnosed and most at risk, especially key populations, men, adolescents, and children. We summarize future directions in HIV testing to speed scale-up and close gaps that are addressed in the WHO 2015 consolidated HIV testing guidelines. In contrast to HIV, action in hepatitis testing and treatment has been fragmented and limited to a few countries, and there remains a large burden of undiagnosed cases globally. We summarize key challenges in the hepatitis testing response, including lack of simple, reliable, and low-cost diagnostic tests, laboratory capacity, and testing facilities; inadequate data to guide country specific hepatitis testing approaches and who to screen; stigmatization and social

  5. Caffeine challenge test and panic disorder: a systematic literature review.

    PubMed

    Vilarim, Marina Machado; Rocha Araujo, Daniele Marano; Nardi, Antonio Egidio

    2011-08-01

    This systematic review aimed to examine the results of studies that have investigated the induction of panic attacks and/or the anxiogenic effect of the caffeine challenge test in patients with panic disorder. The literature search was performed in PubMed, Biblioteca Virtual em Saúde and the ISI Web of Knowledge. The words used for the search were caffeine, caffeine challenge test, panic disorder, panic attacks and anxiety disorder. In total, we selected eight randomized, double-blind studies where caffeine was administered orally, and none of them controlled for confounding factors in the analysis. The percentage of loss during follow-up ranged between 14.3% and 73.1%. The eight studies all showed a positive association between caffeine and anxiogenic effects and/or panic disorder.

  6. Data Sharing and Reproducible Clinical Genetic Testing: Successes and Challenges

    PubMed Central

    Yang, Shan; Cline, Melissa; Zhang, Can; Paten, Benedict; Lincoln, Stephen e.

    2016-01-01

    Open sharing of clinical genetic data promises to both monitor and eventually improve the reproducibility of variant interpretation among clinical testing laboratories. A significant public data resource has been developed by the NIH ClinVar initiative, which includes submissions from hundreds of laboratories and clinics worldwide. We analyzed a subset of ClinVar data focused on specific clinical areas and we find high reproducibility (>90% concordance) among labs, although challenges for the community are clearly identified in this dataset. We further review results for the commonly tested BRCA1 and BRCA2 genes, which show even higher concordance, although the significant fragmentation of data into different silos presents an ongoing challenge now being addressed by the BRCA Exchange. We encourage all laboratories and clinics to contribute to these important resources. PMID:27896972

  7. Comparison of the immunological responses and efficacy of gamma-irradiated V3526 vaccine formulations against subcutaneous and aerosol challenge with Venezuelan equine encephalitis virus subtype IAB.

    PubMed

    Martin, Shannon S; Bakken, Russell R; Lind, Cathleen M; Garcia, Patricia; Jenkins, Erin; Glass, Pamela J; Parker, Michael D; Hart, Mary Kate; Fine, Donald L

    2010-01-22

    We recently developed a gamma-irradiation method to inactivate V3526, a live-attenuated Venezuelan equine encephalitis virus (VEEV) vaccine candidate. Dosage and schedule studies were conducted to evaluate the immunogenicity and efficacy of gamma-irradiated V3526 (gV3526). Subcutaneous (SC) and low dosage intramuscular (IM) administration of gV3526 were highly effective in protecting mice against a SC challenge with VEEV IA/B Trinidad Donkey strain, but not against an equivalent aerosol challenge. More robust immune responses and increased protective efficacy were noted when the IM dosage of gV3526 was increased. IM administration of gV3526 formulated with either CpG or CpG plus Alhydrogel further augmented the immune response in mice and resulted in 100% protection against aerosol challenge.

  8. The Bronchial Challenge Test: A New Direction in Asthmatic Management

    PubMed Central

    Dixon, Calvin

    1983-01-01

    Bronchial asthma can be diagnosed when a patient develops the clinical manifestations of bronchial reactivity: wheezing, cough, tachypnea, and dyspnea. Occasionally, despite immunotherapy, bronchodilator therapy, and avoidance of the provocative factors, some asthmatic patients do not respond to treatment. Bronchial inhalation challenge, a method to test airway reactivity after inhalation of a nonspecific drug, can be used to plan and assess different modes of treatment, as well as screen for bronchial hyperreactivity in an occupational setting. PMID:6827612

  9. CHANGES IN OPERATING PROCEDURES FOR AEROSOL CONCENTRATION UNIFORMITY FOR PM2.5 AND PM10 SAMPLER TESTING

    EPA Science Inventory

    This technical note documents changes in the standard operating procedures used at the Environmental Protection Agency's (U.S. EPA) aerosol testing wind tunnel facility for testing of particulate matter monitoring methods of PM2.5 and PM10. These changes are relative to the op...

  10. Challenges to Integrating Pharmacogenetic Testing into Medication Therapy Management

    PubMed Central

    Allen LaPointe, Nancy M.; Moaddeb, Jivan

    2015-01-01

    Background Some have proposed the integration of pharmacogenetic (PGx) testing into medication therapy management (MTM) to enable further refinement of treatment(s) to reduce risk of adverse responses and improve efficacy. PGx testing involves the analysis of genetic variants associated with therapeutic or adverse response and may be useful in enhancing the ability to identify ineffective and/or harmful drugs or drug combinations. This “enhanced” MTM might also reduce patient concerns about side effects and increase confidence that the medication is effective, addressing two key factors that impact patient adherence - concern and necessity. However, the feasibility and effectiveness of the integration of PGx testing into MTM in clinical practice has not yet been determined. Objectives In this paper, we consider some of the challenges to the integration and delivery of PGx testing in MTM services. What is already known about this subject While the addition of pharmacogenetic testing has been suggested, little literature exists exploring the challenges or feasibility of doing so. PMID:25803768

  11. Stability Testing of Herbal Drugs: Challenges, Regulatory Compliance and Perspectives.

    PubMed

    Bansal, Gulshan; Suthar, Nancy; Kaur, Jasmeen; Jain, Astha

    2016-07-01

    Stability testing is an important component of herbal drugs and products (HDPs) development process. Drugs regulatory agencies across the globe have recommended guidelines for the conduct of stability studies on HDPs, which require that stability data should be included in the product registration dossier. From the scientific viewpoint, numerous chemical constituents in an herbal drug are liable to varied chemical reactions under the influence of different conditions during its shelf life. These reactions can lead to altered chemical composition of HDP and consequently altered therapeutic profile. Many reports on stability testing of HDPs have appeared in literature since the last 10 years. A review of these reports reveals that there is wide variability in temperature (-80 to 100 °C), humidity (0-100%) and duration (a few hours-36 months) for stability assessment of HDPs. Of these, only 1% studies are conducted in compliance with the regulatory guidelines for stability testing. The present review is aimed at compiling all stability testing reports, understanding key challenges in stability testing of HDPs and suggesting possible solutions for these. The key challenges are classified as chemical complexity and biochemical composition variability in raw material, selection of marker(s) and influences of enzymes. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Laboratory Testing and Calibration of the Nuclei-Mode Aerosol Size Spectrometer

    NASA Technical Reports Server (NTRS)

    Brock, Charles A.

    1999-01-01

    This grant was awarded to complete testing and calibration of a new instrument, the nuclei-mode aerosol size spectrometer (N-MASS), following its use in the WB-57F Aerosol Measurement (WAM) campaign in early 1998. The N-MASS measures the size distribution of particles in the 4-60 nm diameter range with 1-Hz response at typical free tropospheric conditions. Specific tasks to have been completed under the auspices of this award were: 1) to experimentally determine the instrumental sampling efficiency; 2) to determine the effects of varying temperatures and flows on N-MASS performance; and 3) to calibrate the N-MASS at typical flight conditions as operated in WAM. The work outlined above has been completed, and a journal manuscript based on this work and that describes the performance of the N-MASS is in preparation. Following a brief description of the principles of operation of the instrument, the major findings of this study are described.

  13. Ability evaluation by binary tests: Problems, challenges & recent advances

    NASA Astrophysics Data System (ADS)

    Bashkansky, E.; Turetsky, V.

    2016-11-01

    Binary tests designed to measure abilities of objects under test (OUTs) are widely used in different fields of measurement theory and practice. The number of test items in such tests is usually very limited. The response to each test item provides only one bit of information per OUT. The problem of correct ability assessment is even more complicated, when the levels of difficulty of the test items are unknown beforehand. This fact makes the search for effective ways of planning and processing the results of such tests highly relevant. In recent years, there has been some progress in this direction, generated by both the development of computational tools and the emergence of new ideas. The latter are associated with the use of so-called “scale invariant item response models”. Together with maximum likelihood estimation (MLE) approach, they helped to solve some problems of engineering and proficiency testing. However, several issues related to the assessment of uncertainties, replications scheduling, the use of placebo, as well as evaluation of multidimensional abilities still present a challenge for researchers. The authors attempt to outline the ways to solve the above problems.

  14. The MESSy aerosol submodel MADE3 (v2.0b): description and a box model test

    NASA Astrophysics Data System (ADS)

    Kaiser, J. C.; Hendricks, J.; Righi, M.; Riemer, N.; Zaveri, R. A.; Metzger, S.; Aquila, V.

    2014-06-01

    We introduce MADE3 (Modal Aerosol Dynamics model for Europe, adapted for global applications, 3rd generation; version: MADE3v2.0b), an aerosol dynamics submodel for application within the MESSy framework (Modular Earth Submodel System). MADE3 builds on the predecessor aerosol submodels MADE and MADE-in. Its main new features are the explicit representation of coarse mode particle interactions both with other particles and with condensable gases, and the inclusion of hydrochloric acid (HCl) / chloride (Cl) partitioning between the gas and condensed phases. The aerosol size distribution is represented in the new submodel as a superposition of nine lognormal modes: one for fully soluble particles, one for insoluble particles, and one for mixed particles in each of three size ranges (Aitken, accumulation, and coarse mode size ranges). In order to assess the performance of MADE3 we compare it to its predecessor MADE and to the much more detailed particle-resolved aerosol model PartMC-MOSAIC in a box model simulation of an idealised marine boundary layer test case. MADE3 and MADE results are very similar, except in the coarse mode, where the aerosol is dominated by sea spray particles. Cl is reduced in MADE3 with respect to MADE due to the HCl / Cl partitioning that leads to Cl removal from the sea spray aerosol in our test case. Additionally, the aerosol nitrate concentration is higher in MADE3 due to the condensation of nitric acid on coarse mode particles. MADE3 and PartMC-MOSAIC show substantial differences in the fine particle size distributions (sizes ≲ 2 μm) that could be relevant when simulating climate effects on a global scale. Nevertheless, the agreement between MADE3 and PartMC-MOSAIC is very good when it comes to coarse particle size distributions (sizes ≳ 2 μm), and also in terms of aerosol composition. Considering these results and the well-established ability of MADE in reproducing observed aerosol loadings and composition, MADE3 seems suitable for

  15. The MESSy aerosol submodel MADE3 (v2.0b): description and a box model test

    SciTech Connect

    Kaiser, J. C.; Hendricks, J.; Righi, M.; Riemer, N.; Zaveri, R. A.; Metzger, S.; Aquila, V.

    2014-01-01

    We introduce MADE3 (Modal Aerosol Dynamics model for Europe, adapted for global applications, 3rd generation; version: MADE3v2.0b), an aerosol dynamics submodel for application within the MESSy framework (Modular Earth Submodel System). MADE3 builds on the predecessor aerosol submodels MADE and MADE-in. Its main new features are the explicit representation of coarse mode particle interactions both with other particles and with condensable gases, and the inclusion of hydrochloric acid (HCl) / chloride (Cl) partitioning between the gas and condensed phases. The aerosol size distribution is represented in the new submodel as a superposition of nine lognormal modes: one for fully soluble particles, one for insoluble particles, and one for mixed particles in each of three size ranges (Aitken, accumulation, and coarse mode size ranges). In order to assess the performance of MADE3 we compare it to its predecessor MADE and to the much more detailed particle-resolved aerosol model PartMC-MOSAIC in a box model simulation of an idealised marine boundary layer test case. MADE3 and MADE results are very similar, except in the coarse mode, where the aerosol is dominated by sea spray particles. Cl is reduced in MADE3 with respect to MADE due to the HCl / Cl partitioning that leads to Cl removal from the sea spray aerosol in our test case. Additionally, the aerosol nitrate concentration is higher in MADE3 due to the condensation of nitric acid on coarse mode particles. MADE3 and PartMC-MOSAIC show substantial differences in the fine particle size distributions (sizes ≲ 2 μm) that could be relevant when simulating climate effects on a global scale. Nevertheless, the agreement between MADE3 and PartMC-MOSAIC is very good when it comes to coarse particle size distributions (sizes ≳ 2 μm), and also in terms of aerosol composition. Finally, considering these results and the well-established ability of MADE in reproducing observed aerosol loadings and composition, MADE3 seems

  16. Heterogeneous uptake of NO2 on Arizona Test Dust under UV-A irradiation: An aerosol flow tube study

    NASA Astrophysics Data System (ADS)

    Dupart, Yoan; Fine, Ludovic; D'Anna, Barbara; George, Christian

    2014-12-01

    The uptake rate of NO2 on Arizona Test Dust aerosols was measured using an aerosol flow tube (AFT). While the uptake rate in the dark could not be measured, the uptake under UV-A irradiation was enhanced, with values in the range from (0.6 ± 0.3) × 10-8, (2.4 ± 0.4) × 10-8. The observed gas phase products were HONO and NO, with yields of at 30% and 9.6%, respectively. The difference between these measurements and those previously reported on macroscopic films are discussed and differences highlighted. Interestingly, a reasonable agreement is observed between the uptake kinetics of NO2 on Arizona Test Dust macroscopic films and aerosols, despite the different experimental approaches. The simplest approach i.e. thin films having a significant porosity, provides similar uptake kinetics to the more complex and realistic AFT approach.

  17. Verification Challenges of Dynamic Testing of Space Flight Hardware

    NASA Technical Reports Server (NTRS)

    Winnitoy, Susan

    2010-01-01

    The Six Degree-of-Freedom Dynamic Test System (SDTS) is a test facility at the National Aeronautics and Space Administration (NASA) Johnson Space Center in Houston, Texas for performing dynamic verification of space structures and hardware. Some examples of past and current tests include the verification of on-orbit robotic inspection systems, space vehicle assembly procedures and docking/berthing systems. The facility is able to integrate a dynamic simulation of on-orbit spacecraft mating or demating using flight-like mechanical interface hardware. A force moment sensor is utilized for input to the simulation during the contact phase, thus simulating the contact dynamics. While the verification of flight hardware presents many unique challenges, one particular area of interest is with respect to the use of external measurement systems to ensure accurate feedback of dynamic contact. There are many commercial off-the-shelf (COTS) measurement systems available on the market, and the test facility measurement systems have evolved over time to include two separate COTS systems. The first system incorporates infra-red sensing cameras, while the second system employs a laser interferometer to determine position and orientation data. The specific technical challenges with the measurement systems in a large dynamic environment include changing thermal and humidity levels, operational area and measurement volume, dynamic tracking, and data synchronization. The facility is located in an expansive high-bay area that is occasionally exposed to outside temperature when large retractable doors at each end of the building are opened. The laser interferometer system, in particular, is vulnerable to the environmental changes in the building. The operational area of the test facility itself is sizeable, ranging from seven meters wide and five meters deep to as much as seven meters high. Both facility measurement systems have desirable measurement volumes and the accuracies vary

  18. Penicillamine challenge test in the diagnosis of Wilson's disease.

    PubMed

    Mazumder, M W; Karim, M B; Rukunuzzaman, M

    2014-07-01

    Wilson's disease (WD) is one of the most common metabolic liver diseases encountered in children. Early diagnosis of the disease is essential because specific treatment can be offered, that will prevent further hepatocellular injury and neurologic complications. There is no single diagnostic test that can exclude or confirm the disease with certainty. Penicillamine challenge has proved itself to be a useful diagnostic test in the detection of WD. The main purpose of this study was to observe the reliability of penicillamine challenge test, in the diagnosis of WD. The cross sectional study was done with a case control design in the department of paediatric gastroenterology & Nutrition, BSMMU, Dhaka. The study was carried out on 60 patients of CLD. Along with other physical findings and laboratory investigations, 24 hours urinary copper excretions were estimated before and after penicillamine challenge. Study results were analyzed statistically. Thirty CLD patients who fulfilled the inclusion and exclusion criteria of WD were considered as cases (Group I) and remaining 30 CLD patients were considered as non-Wilsonian CLD and was labeled as control (Group II). Among the control group, 12 CLD patients were found to be HBsAg positive, 1 had hepatitis-C virus infection, 1 had autoimmune hepatitis and the remaining 16 CLD patients were Cryptogenic. The (mean±SD) age of WD patients was 9.90±28 years; male female ratio was 1.5:1. Most common presentation was ascites (70%). K-F ring was found in 86.7% cases. Serum ceruloplasmin level was found significantly lower in WD patients (mean±SD, 0.1197±23g/L, p<0.001). Baseline urinary copper excretion of WD patients differed significantly from controls (Median 219.0μg/24hour, range 35-2018μg/24hour, versus median 44μg/24hour, range 20-238μg/24hour, p<0.001). Baseline urinary copper excretion above 100μg/24hour was observed in 80% WD patients whereas it was 10% in controls. post penicillamine urinary copper excretion was

  19. Protective effect of two recombinant ricin subunit vaccines in the New Zealand white rabbit subjected to a lethal aerosolized ricin challenge: survival, immunological response, and histopathological findings.

    PubMed

    McLain, Daniel E; Lewis, Bridget S; Chapman, Jennifer L; Wannemacher, Robert W; Lindsey, Changhong Y; Smith, Leonard A

    2012-03-01

    Ricin, isolated from the castor bean plant Ricinus communis, is included on the Centers for Disease Control and Prevention Category B list of bioterrorism agents, indicating that the toxin is moderately easy to disseminate and could result in moderate morbidity rates. This study evaluated two promising recombinant ricin subunit vaccines, one made using an Escherichia coli codon-optimized gene and the other using a yeast codon-optimized gene in E. coli-based fermentations. Rabbits were vaccinated four times over a period of 6 months and challenged with ∼10 to 30 times the median lethal dose of aerosolized ricin. All unvaccinated control rabbits were either found dead or humanely euthanized within 30 h postchallenge, while the rabbits vaccinated with either vaccine survived the exposure without adverse clinical signs. When the protective antibody responses were analyzed, no significant difference was seen between the two vaccines. However, there was a significant difference in the immune response over time for both vaccines tested. Although clinical pathology was unremarkable, significant histological lesions in the control animals included fibrinonecrotic pneumonia, acute necrotizing lesions in the upper respiratory tract, and necrotizing lymphadenitis in the lymph nodes draining the upper and lower respiratory tract. Vaccine-treated rabbits exhibited resolving lesions associated with ricin exposure, namely chronic inflammation in the upper respiratory tract and lungs, fibrosis, type II pneumocyte hyperplasia, and bronchiolitis obliterans. This study confirmed the safety and efficacy of two recombinant ricin subunit vaccines in rabbits, offering potential protection to warfighters and select populations.

  20. Genetically Engineered, Live Attenuated Vaccines Protect Nonhuman Primates Against Aerosol Challenge with a Virulent IE Strain of Venezuelan Equine Encephalitis Virus

    DTIC Science & Technology

    2005-01-21

    Vaccine 23 (2005) 3139–3147 Genetically engineered, live, attenuated vaccines protect nonhuman primates against aerosol challenge with a virulent IE...Prattb, Michael D. Parkerb a Center for Aerobiological Sciences, U.S. Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort...Received 27 August 2004; received in revised form 22 December 2004; accepted 23 December 2004 Available online 21 January 2005 Abstract d w h o a w s f P

  1. Challenges

    ERIC Educational Resources Information Center

    Moore, Thomas R.

    1975-01-01

    Domestic and international challenges facing the National Society for the Prevention of Blindness are discussed; and U.S. and Russian programs in testing and correcting children's vision, developing eye safety programs in agriculture and industry, and disseminating information concerning the detection and treatment of cataracts are compared. (SB)

  2. Differences in aerosolization of Rift Valley fever virus resulting from choice of inhalation exposure chamber: implications for animal challenge studies

    PubMed Central

    Bethel, Laura M.; Powell, Diana S.; Caroline, Amy L.; Hartman, Amy L.

    2014-01-01

    Abstract The aerosol characteristics of Rift Valley fever virus (RVFV) were evaluated to achieve reproducible infection of experimental animals with aerosolized RVFV suitable for animal efficacy studies. Spray factor (SF), the ratio between the concentrations of the aerosolized agent to the agent in the aerosol generator, is used to compare performance differences between aerosol exposures. SF indicates the efficiency of the aerosolization process; a higher SF means a lower nebulizer concentration is needed to achieve a desired inhaled dose. Relative humidity levels as well as the duration of the exposure and choice of exposure chamber all impacted RVFV SF. Differences were also noted between actual and predicted minute volumes for different species of nonhuman primates. While NHP from Old World species (Macaca fascicularis, M. mulatta, Chlorocebus aethiops) generally had a lower actual minute volume than predicted, the actual minute volume for marmosets (Callithrix jacchus) was higher than predicted (150% for marmosets compared with an average of 35% for all other species examined). All of these factors (relative humidity, chamber, duration, and minute volume) impact the ability to reliably and reproducibly deliver a specific dose of aerosolized RVFV. The implications of these findings for future pivotal efficacy studies are discussed. PMID:24532259

  3. Genetic testing in nephrotic syndrome--challenges and opportunities.

    PubMed

    Gbadegesin, Rasheed A; Winn, Michelle P; Smoyer, William E

    2013-03-01

    Monogenic nephrotic syndrome (nephrotic syndrome caused by a single gene defect) is responsible for only a small percentage of cases of nephrotic syndrome, but information from studies of the unique cohort of patients with this form of the disease has dramatically improved our understanding of the disease pathogenesis. The use of genetic testing in the management of children and adults with nephrotic syndrome poses unique challenges for clinicians in terms of who to test and how to use the information obtained from testing in the clinical setting. In our view, not enough data exist at present to justify the routine genetic testing of all patients with nephrotic syndrome. Testing is warranted, however, in patients with congenital nephrotic syndrome (onset at 0-3 months), infantile nephrotic syndrome (onset at 3-12 months), a family history of nephrotic syndrome, and those in whom nephrotic syndrome is associated with other congenital malformations. The family and/or the patient should be given complete and unbiased information on the potential benefits and risks associated with therapy, including the reported outcomes of treatment in patients with similar mutations. Based on the data available in the literature so far, intensive immunosuppressive treatment is probably not indicated in monogenic nephrotic syndrome if complete or partial remission has not been achieved within 6 weeks of starting treatment. We advocate that family members of individuals with genetic forms of nephrotic syndrome undergo routine genetic testing prior to living-related kidney transplantation. Prospective, multicentre studies are needed to more completely determine the burden of disease caused by monogenic nephrotic syndrome, and randomized controlled trials are needed to clarify the presence or absence of clinical responses of monogenic nephrotic syndrome to available therapies.

  4. Air detoxification with nanosize TiO2 aerosol tested on mice.

    PubMed

    Besov, A S; Krivova, N A; Vorontsov, A V; Zaeva, O B; Kozlov, D V; Vorozhtsov, A B; Parmon, V N; Sakovich, G V; Komarov, V F; Smirniotis, P G; Eisenreich, N

    2010-01-15

    A method for fast air purification using high concentration aerosol of TiO(2) nanoparticles is evaluated in a model chemical catastrophe involving toxic vapors of diisopropyl fluorophosphate (DFP). Mice are used as human model in a closed 100 dm(3) chamber. Exposure of mice to 37 ppm of DFP vapor for 15 min resulted in acute poisoning. Spraying TiO(2) aerosol in 2 min after the start of exposure to DFP vapors resulted in quick removal of DFP vapors from the chamber's air. Animals did not show signs of poisoning after the decontamination experiment and exposure to TiO(2) aerosol alone. Reactive oxygen species (ROS) and antioxidant activity (AOA) of mice blood plasma were measured for animals exposed to sound of aerosol generator, DFP vapors, TiO(2) aerosol and DFP vapors+TiO(2) aerosol. Reduced ROS and increased AOA were found for mice exposure to sound, DFP and TiO(2) aerosol. Exposure to DFP and decontamination with TiO(2) nanoparticles resulted in decreased AOA in 48 h following the exposure. The results suggest that application of TiO(2) aerosol is a powerful method of air purification from toxic hydrolysable compounds with moderate health aftermaths and requires further study and optimization.

  5. Simulation test of aerosol generation from vessels in the pre-treatment system of fuel reprocessing

    SciTech Connect

    Fujine, Sachio; Kitamura, Koichiro; Kihara, Takehiro

    1997-08-01

    Aerosol concentration and droplet size are measured in off-gas of vessel under various conditions by changing off-gas flow rate, stirring air flow rate, salts concentration and temperature of nitrate solution. Aerosols are also measured under evaporation and air-lift operation. 4 refs., 6 figs.

  6. Organotypic liver culture models: Meeting current challenges in toxicity testing

    PubMed Central

    LeCluyse, Edward L.; Witek, Rafal P.; Andersen, Melvin E.; Powers, Mark J.

    2012-01-01

    Prediction of chemical-induced hepatotoxicity in humans from in vitro data continues to be a significant challenge for the pharmaceutical and chemical industries. Generally, conventional in vitro hepatic model systems (i.e. 2-D static monocultures of primary or immortalized hepatocytes) are limited by their inability to maintain histotypic and phenotypic characteristics over time in culture, including stable expression of clearance and bioactivation pathways, as well as complex adaptive responses to chemical exposure. These systems are less than ideal for longer-term toxicity evaluations and elucidation of key cellular and molecular events involved in primary and secondary adaptation to chemical exposure, or for identification of important mediators of inflammation, proliferation and apoptosis. Progress in implementing a more effective strategy for in vitro-in vivo extrapolation and human risk assessment depends on significant advances in tissue culture technology and increasing their level of biological complexity. This article describes the current and ongoing need for more relevant, organotypic in vitro surrogate systems of human liver and recent efforts to recreate the multicellular architecture and hemodynamic properties of the liver using novel culture platforms. As these systems become more widely used for chemical and drug toxicity testing, there will be a corresponding need to establish standardized testing conditions, endpoint analyses and acceptance criteria. In the future, a balanced approach between sample throughput and biological relevance should provide better in vitro tools that are complementary with animal testing and assist in conducting more predictive human risk assessment. PMID:22582993

  7. Aerosol Properties from Multi-spectral and Multi-angular Aircraft 4STAR Observations: Expected Advantages and Challenges

    SciTech Connect

    Kassianov, Evgueni I.; Flynn, Connor J.; Redemann, Jens; Schmid, Beat; Russell, P. B.; Sinyuk, Alexander

    2012-11-01

    The airborne Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) is developed to retrieve aerosol microphysical and optical properties from multi-angular and multi-spectral measurements of sky radiance and direct-beam sun transmittance. The necessarily compact design of the 4STAR may cause noticeable apparent enhancement of sky radiance at small scattering angles. We assess the sensitivity of expected 4STAR-based aerosol retrieval to such enhancement by applying the operational AERONET retrieval code and constructed synthetic 4STARlike data. Also, we assess the sensitivity of the broadband fluxes and the direct aerosol radiative forcing to uncertainties in aerosol retrievals associated with the sky radiance enhancement. Our sensitivity study results suggest that the 4STARbased aerosol retrieval has limitations in obtaining detailed information on particle size distribution and scattering phase function. However, these limitations have small impact on the retrieved bulk optical parameters, such as the asymmetry factor (up to 4%, or ±0.02) and single-scattering albedo (up to 2%, or ±0.02), and the calculated direct aerosol radiative forcing (up to 6%, or 2 Wm-2).

  8. Rapid HIV testing for developing countries: the challenge of false-negative tests

    NASA Astrophysics Data System (ADS)

    Yogev, Ram

    2012-06-01

    It is a common practice in resource-constrained countries to accept two positive rapid HIV antibody test results as diagnostic for HIV infection. Because these tests are inexpensive and results are obtained quickly, they are recommended by the WHO to "scale-up" HIV testing to increase the number of people tested. The negative predictive value of rapid HIV tests is so high that negative results are considered conclusive despite the fact that false-negative results can occur in several situations. While the specificity and sensitivity of rapid HIV tests in resource-rich countries is acceptable, there are only limited data about their performance in resource-constrained countries. The challenges of rapid HIV testing in these situations will be discussed.

  9. Challenges and Opportunities for Testing Students Who Are Deaf or Hard of Hearing: Information for Educators on Creating Test Equity. Test Equity Considerations: Schools

    ERIC Educational Resources Information Center

    PEPNet-West, 2010

    2010-01-01

    For most students, test taking is a challenge. For students who are deaf or hard of hearing, classroom quizzes, tests, and exams are even more challenging. Standardized tests--The SAT, ACT, state proficiency tests, No Child Left Behind annual tests, and psychoeducational evaluations--present additional challenges for students who are deaf or hard…

  10. A comparative assessment of cigarette smoke aerosols using an in vitro air–liquid interface cytotoxicity test

    PubMed Central

    Thorne, David; Dalrymple, Annette; Dillon, Deborah; Duke, Martin; Meredith, Clive

    2015-01-01

    Abstract This study describes the evaluation of a modified air-liquid interface BALB/c 3T3 cytotoxicity method for the assessment of smoke aerosols in vitro. The functionality and applicability of this modified protocol was assessed by comparing the cytotoxicity profiles from eight different cigarettes. Three reference cigarettes, 1R5F, 3R4F and CORESTA Monitor 7 were used to put the data into perspective and five bespoke experimental products were manufactured, ensuring a balanced and controlled study. Manufactured cigarettes were matched for key variables such as nicotine delivery, puff number, pressure drop, ventilation, carbon monoxide, nicotine free dry particulate matter and blend, but significantly modified for vapor phase delivery, via the addition of two different types and quantities of adsorptive carbon. Specifically manufacturing products ensures comparisons can be made in a consistent manner and allows the research to ask targeted questions, without confounding product variables. The results demonstrate vapor-phase associated cytotoxic effects and clear differences between the products tested and their cytotoxic profiles. This study has further characterized the in vitro vapor phase biological response relationship and confirmed that the biological response is directly proportional to the amount of available vapor phase toxicants in cigarette smoke, when using a Vitrocell® VC 10 exposure system. This study further supports and strengthens the use of aerosol based exposure options for the appropriate analysis of cigarette smoke induced responses in vitro and may be especially beneficial when comparing aerosols generated from alternative tobacco aerosol products. PMID:26339773

  11. New X-ray testing methods of aerosol products for industrial radiography

    NASA Astrophysics Data System (ADS)

    Bozydar Knyziak, Adrian; Rzodkiewicz, Witold; Kaczorowska, Ewa; Derlacinski, Michal

    2017-02-01

    An amount of product in e.g. an aerosol canister is not difficult to estimate by weighing a filled can and subtracting the tare of packaging. In this way, we can obtain the net weight of the ingredients present in the can. Although, this does not indicate the volumetric content. Therefore, in the paper, the fundamental (the weight method and given by FEICA) and new methods (given by authors) related to the determination of the volumetric content of canister filled with aeorosol products are presented. The new methods are based on direct digital radiography (DR) using X-ray radiation. For the needs of new methods, the X-ray CCD-DR imaging system was built and developed in our Laboratory in Department of Radiation and Vibration at the Central Office of Measures. For comparison purposes, with regard to the volumetric content, a lot of metal cans of capacities 140, 185, 450, 700 ml were inspected. In future, computed tomography (CT) for industrial radiography in our laboratory will be used. Currently, an algorithm for CT is being tested. It will give us possibility for very precise measurements to determine volumetric content of examined canisters.

  12. Aerosol distribution apparatus

    DOEpatents

    Hanson, W.D.

    An apparatus for uniformly distributing an aerosol to a plurality of filters mounted in a plenum, wherein the aerosol and air are forced through a manifold system by means of a jet pump and released into the plenum through orifices in the manifold. The apparatus allows for the simultaneous aerosol-testing of all the filters in the plenum.

  13. EDITORIAL: Aerosol cloud interactions—a challenge for measurements and modeling at the cutting edge of cloud climate interactions

    NASA Astrophysics Data System (ADS)

    Spichtinger, Peter; Cziczo, Daniel J.

    2008-04-01

    Research in aerosol properties and cloud characteristics have historically been considered two separate disciplines within the field of atmospheric science. As such, it has been uncommon for a single researcher, or even research group, to have considerable expertise in both subject areas. The recent attention paid to global climate change has shown that clouds can have a considerable effect on the Earth's climate and that one of the most uncertain aspects in their formation, persistence, and ultimate dissipation is the role played by aerosols. This highlights the need for researchers in both disciplines to interact more closely than they have in the past. This is the vision behind this focus issue of Environmental Research Letters. Certain interactions between aerosols and clouds are relatively well studied and understood. For example, it is known that an increase in the aerosol concentration will increase the number of droplets in warm clouds, decrease their average size, reduce the rate of precipitation, and extend the lifetime. Other effects are not as well known. For example, persistent ice super-saturated conditions are observed in the upper troposphere that appear to exceed our understanding of the conditions required for cirrus cloud formation. Further, the interplay of dynamics versus effects purely attributed to aerosols remains highly uncertain. The purpose of this focus issue is to consider the current state of knowledge of aerosol/cloud interactions, to define the contemporary uncertainties, and to outline research foci as we strive to better understand the Earth's climate system. This focus issue brings together laboratory experiments, field data, and model studies. The authors address issues associated with warm liquid water, cold ice, and intermediate temperature mixed-phase clouds. The topics include the uncertainty associated with the effect of black carbon and organics, aerosol types of anthropogenic interest, on droplet and ice formation. Phases

  14. Test Results of Level A Suits to Challenge by Chemical and Biological Warfare Agents and Simulants: Summary Report

    DTIC Science & Technology

    1998-06-01

    Agent Permeation of GB and HD Through 25-Mil Chemical Protective Glove 30 3.3 System Test (Aerosol Simulant) 3.3.1 System Test (Aerosol Simulant... Chemical Protective Glove GB Permeation 176 Appendix Q: Commander Brigade F91 Table Q - 3: Commander Brigade F91: System Test (Vapor Simulant) Results No...capability to protect in a chemical agent or biological agent environment. Each

  15. The MICROSCOPE mission: a challenging free fall test

    NASA Astrophysics Data System (ADS)

    Touboul, Pierre; Metris, Gilles; Robert, Alain; Levy, Agnes; Campergue, Gerard

    The electrostatic inertial sensors which compose the payload of the dedicated MICROSCOPE space mission include cylindrical test masses, made of different materials. Their orbital motion will be observed for the accurate test of the Universality of Free Fall, so performed with an ac-curacy of at least 10-15 . These Titanium and Platinum alloys concentric masses are maintained motion less at the center of a very accurate silica cage by means of electrostatic actuators which manage the electrical fields surrounding permanently the masses. Same gold coated electrodes are not only used for generating these electrical fields but also to measure any mass displace-ment with an accuracy better than 10-11 m by means of a well arranged set of capacitive sensors. The MICROSCOPE drag free satellite is controlled Earth pointing or rotating about the normal to the orbital plane with a very stable angular velocity. A very stringent control of the residual accelerations seen by the scientific payload itself is applied thanks to the drag free system, except the Earth common gravity field. At the selected circular orbit, with 810 km altitude and less than 5.10-3 eccentricity, the effects of the gravity gradients are carefully managed by mass centring and data corrections. On board thermal environment is also a key element of the detection of any violation of Einstein Equivalence Principle as most attempts of Grand Unification theories seem to conduct. An overview of the prepared mission is presented with the established strategies to deal with the space experiment specific challenges.

  16. Dopamine challenge tests as an indicator of psychological traits.

    PubMed

    Netter, P

    2006-03-01

    After discussing some introductory considerations about the value of challenge tests in general for discriminating personality dimensions which are considered extrapolations of psychopathological diseases, the present paper outlines the matter of responsivity to agonistic and antagonistic dopaminergic drugs or drugs of different mechanisms of action in the dopaminergic system, and elucidates that different hormones elicited by dopaminergic substances (prolactin, growth hormone) may indicate personality related differences in susceptibility of different brain areas. A further point was to demonstrate not only the well known relationship of dopaminergic hyperactivity with reward seeking and motivational factors associated with extraversion and novelty seeking, but also the relationship of dopaminergic hypofunction with the personality dimension of depression which had already been reported in studies on animals and psychiatric patients. A final point was to demonstrate that besides size of hormone responses additional parameters like time of response onset and initial prolactin increase can be used as biochemical indicators for identifying certain personality types, like highly depressive neurotic persons characterized by lower and later dopamine responses as compared to low depressives, and extraverted sensation-seeking types responding by an initial prolactin peak as opposed to low sensation seekers.

  17. Immunogenicity and efficacy against lethal aerosol staphylococcal enterotoxin B challenge in monkeys by intramuscular and respiratory delivery of proteosome-toxoid vaccines.

    PubMed Central

    Lowell, G H; Colleton, C; Frost, D; Kaminski, R W; Hughes, M; Hatch, J; Hooper, C; Estep, J; Pitt, L; Topper, M; Hunt, R E; Baker, W; Baze, W B

    1996-01-01

    Staphylococcal enterotoxin B (SEB), a primary cause of food poisoning, is also a superantigen that can cause toxic shock after traumatic or surgical staphylococcal wound [correction of would] infections or viral influenza-associated staphylococcal superinfections or when aerosolized for use as a potential biologic warfare threat agent. Intranasal or intramuscular (i.m.) immunization with formalinized SEB toxoid formulated with meningococcal outer membrane protein proteosomes has previously been shown to be immunogenic and protective against lethal respiratory or parenteral SEB challenge in murine models of SEB intoxication. Here, it is demonstrated that immunization of nonhuman primates with the proteosome-SEB toxoid vaccine is safe, immunogenic, and protective against lethal aerosol challenge with 15 50% lethal doses of SEB. Monkeys (10 per group) were primed i.m. and given booster injections by either the i.m. or intratracheal route without adverse side effects. Anamnestic anti-SEB serum immunoglobulin G (IgG) responses were elicited in all monkeys, but strong IgA responses in sera and bronchial secretions were elicited both pre- and post-SEB challenge only in monkeys given booster injections intratracheally. The proteosome-SEB toxoid vaccine was efficacious by both routes in protecting 100% of monkeys against severe symptomatology and death from aerosolized-SEB intoxication. These data confirm the safety, immunogenicity, and efficacy in monkeys of parenteral and respiratory vaccination with the proteosome-SEB toxoid, thereby supporting clinical trials of this vaccine in humans. The safety and enhancement of both bronchial and systemic IgA and IgG responses by the proteosome vaccine delivered by a respiratory route are also encouraging for the development of mucosally delivered proteosome vaccines to protect against SEB and other toxic or infectious respiratory pathogens. PMID:8890226

  18. [Inhalation therapy: inhaled corticosteroids in ENT, development and technical challenges of powder inhalers, nebulisers synchronized with breathing and aerosol size distribution. GAT aerosolstorming, Paris 2012].

    PubMed

    Le Guen, P; Peron, N; Durand, M; Pourchez, J; Cavaillon, P; Reychler, G; Vecellio, L; Dubus, J-C

    2013-10-01

    The working group on aerosol therapy (GAT) of the Société de Pneumologie de Langue Française (SPLF) has organized its third Aerosolstorming in 2012. During one single day, different aspects of inhaled therapies have been treated and are detailed in two articles, this one being the second. This text deals with the indications of inhaled corticosteroids in ENT, the development and technical challenges of powder inhalers, the advantages and disadvantages of each type of technologies to measure the particle sizes of inhaled treatments.

  19. Development and Testing of the New Surface LER Climatology for OMI UV Aerosol Retrievals

    NASA Technical Reports Server (NTRS)

    Gupta, Pawan; Torres, Omar; Jethva, Hiren; Ahn, Changwoo

    2014-01-01

    Ozone Monitoring Instrument (OMI) onboard Aura satellite retrieved aerosols properties using UV part of solar spectrum. The OMI near UV aerosol algorithm (OMAERUV) is a global inversion scheme which retrieves aerosol properties both over ocean and land. The current version of the algorithm makes use of TOMS derived Lambertian Equivalent Reflectance (LER) climatology. A new monthly climatology of surface LER at 354 and 388 nm have been developed. This will replace TOMS LER (380 nm and 354nm) climatology in OMI near UV aerosol retrieval algorithm. The main objectives of this study is to produce high resolution (quarter degree) surface LER sets as compared to existing one degree TOMS surface LERs, to product instrument and wavelength consistent surface climatology. Nine years of OMI observations have been used to derive monthly climatology of surface LER. MODIS derived aerosol optical depth (AOD) have been used to make aerosol corrections on OMI wavelengths. MODIS derived BRDF adjusted reflectance product has been also used to capture seasonal changes in the surface characteristics. Finally spatial and temporal averaging techniques have been used to fill the gaps around the globes, especially in the regions with consistent cloud cover such as Amazon. After implementation of new surface data in the research version of algorithm, comparisons of AOD and single scattering albedo (SSA) have been performed over global AERONET sites for year 2007. Preliminary results shows improvements in AOD retrievals globally but more significance improvement were observed over desert and bright locations. We will present methodology of deriving surface data sets and will discuss the observed changes in retrieved aerosol properties with respect to reference AERONET measurements.

  20. Aerosol delivery to ventilated infant and pediatric patients.

    PubMed

    Fink, James B

    2004-06-01

    Infants have low tidal volume, vital capacity, and functional residual capacity, and short respiratory cycles (low I:E ratio), which result in a low residence time for aerosol particles and, thus, low pulmonary deposition of aerosol particles (< 1% of the nominal dose), compared to adults (8-22%). Scintigraphy data suggest aerosol deposition of < 1% in both intubated and nonintubated infants. In vitro testing appears to overestimate pulmonary deposition, partly because in vitro testing does not account for exhaled aerosol. Animal models of infant ventilation tend to agree with data from human studies. However, though only a small percentage of the aerosol deposits in the lung, infants nevertheless receive considerably more aerosolized drug per kilogram of body weight than do adults. Efficient aerosol delivery to infants is challenging because of low deposition and high inter-patient and intra-patient variability, but existing systems can effectively delivery various aerosolized drugs, including bronchodilators, anti-inflammatories, and anti-infectives. Use of a nebulizer that has a low residual volume (of drug remaining in the device after nebulization) delivers up to 13%. Awareness of the variables that impact aerosol delivery efficiency can result in more effective treatment of mechanically ventilated infants.

  1. Word Families and Frequency Bands in Vocabulary Tests: Challenging Conventions

    ERIC Educational Resources Information Center

    Kremmel, Benjamin

    2016-01-01

    Vocabulary test development often appears to be based on the design principles of previous tests, without questioning or empirically examining the assumptions underlying those principles. Given the current proliferation of vocabulary tests, it seems timely for the field of vocabulary testing to problematize some of those traditionalised…

  2. EMC Test Challenges for NASA's James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    McCloskey, John

    2016-01-01

    This presentation describes the electromagnetic compatibility (EMC) tests performed on the Integrated Science Instrument Module (ISIM), the science payload of the James Webb Space Telescope (JWST), at NASAs Goddard Space Flight Center (GSFC) in August 2015. By its very nature of being an integrated payload, it could be treated as neither a unit level test nor an integrated spacecraft observatory test. Non-standard test criteria are described along with non-standard test methods that had to be developed in order to evaluate them. Results are presented to demonstrate that all test criteria were met in less than the time allocated.

  3. EMC Test Challenges for NASAs James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    McCloskey, John

    2016-01-01

    This presentation describes the electromagnetic compatibility (EMC) tests performed on the Integrated Science Instrument Module (ISIM), the science payload of the James Webb Space Telescope (JWST), at NASAs Goddard Space Flight Center (GSFC) in August 2015. By its very nature of being an integrated payload, it could be treated as neither a unit level test nor an integrated spacecraft observatory test. Non-standard test criteria are described along with non-standard test methods that had to be developed in order to evaluate them. Results are presented to demonstrate that all test criteria were met in less than the time allocated.

  4. Respirator Filter Efficiency Testing Against Particulate and Biological Aerosols Under Moderate to High Flow Rates

    DTIC Science & Technology

    2006-08-01

    stopped and the filter removed from the system for analysis. Polonium - 210 static eliminators were used to minimize particle loss during transport to...may provide a considerable overestimate of filter performance. Brosseau et al. (1990) compared the collection of silica and asbestos aerosols by DM...a half times as great as that measured under steady flow conditions, which is consistent with the results of Stafford et al. (1973). The asbestos

  5. Testing the MODIS Satellite Retrieval of Aerosol Fine-Mode Fraction

    NASA Technical Reports Server (NTRS)

    Anderson, Theodore L.; Wu, Yonghua; Chu, D. Allen; Schmid, Beat; Redemann, Jens; Dubovik, Oleg

    2005-01-01

    Satellite retrievals of the fine-mode fraction (FMF) of midvisible aerosol optical depth, tau, are potentially valuable for constraining chemical transport models and for assessing the global distribution of anthropogenic aerosols. Here we compare satellite retrievals of FMF from the Moderate Resolution Imaging Spectroradiometer (MODIS) to suborbital data on the submicrometer fraction (SMF) of tau. SMF is a closely related parameter that is directly measurable by in situ techniques. The primary suborbital method uses in situ profiling of SMF combined with airborne Sun photometry both to validate the in situ estimate of ambient extinction and to take into account the aerosol above the highest flight level. This method is independent of the satellite retrieval and has well-known accuracy but entails considerable logistical and technical difficulties. An alternate method uses Sun photometer measurements near the surface and an empirical relation between SMF and the Angstrom exponent, A, a measure of the wavelength dependence of optical depth or extinction. Eleven primary and fifteen alternate comparisons are examined involving varying mixtures of dust, sea salt, and pollution in the vicinity of Korea and Japan. MODIS ocean retrievals of FMF are shown to be systematically higher than suborbital estimates of SMF by about 0.2. The most significant cause of this discrepancy involves the relationship between 5 and fine-mode partitioning; in situ measurements indicate a systematically different relationship from what is assumed in the satellite retrievals. Based on these findings, we recommend: (1) satellite programs should concentrate on retrieving and validating since an excellent validation program is in place for doing this, and (2) suborbital measurements should be used to derive relationships between A and fine-mode partitioning to allow interpretation of the satellite data in terms of fine-mode aerosol optical depth.

  6. [Non-invasive prenatal testing: challenges for future implementation].

    PubMed

    Henneman, Lidewij; Page-Chrisiaens, G C M L Lieve; Oepkes, Dick

    2015-01-01

    The non-invasive prenatal test (NIPT) is an accurate and safe test in which blood from the pregnant woman is used to investigate if the unborn child possibly has trisomy 21 (Down's syndrome), trisomy 18 (Edwards' syndrome) or trisomy 13 (Patau syndrome). Since April 2014 the NIPT has been available in the Netherlands as part of the TRIDENT implementation project for those in whom the first trimester combined test showed an elevated risk (> 1:200) of trisomy, or on medical indication, as an alternative to chorionic villous sampling or amniocentesis. Since the introduction of the NIPT the use of these invasive tests, which are associated with a risk of miscarriage, has fallen steeply. The NIPT may replace the combined test. Also the number of conditions that is tested for can be increased. Modification of current prenatal screening will require extensive discussion, but whatever the modification, careful counseling remains essential to facilitate pregnant women's autonomous reproductive decision making.

  7. Environmental Technology Verification: Supplement to Test/QA Plan for Biological and Aerosol Testing of General Ventilation Air Cleaners; Bioaerosol Inactivation Efficiency by HVAC In-Duct Ultraviolet Light Air Cleaners

    EPA Science Inventory

    The Air Pollution Control Technology Verification Center has selected general ventilation air cleaners as a technology area. The Generic Verification Protocol for Biological and Aerosol Testing of General Ventilation Air Cleaners is on the Environmental Technology Verification we...

  8. Aerosol Delivery of a Candidate Universal Influenza Vaccine Reduces Viral Load in Pigs Challenged with Pandemic H1N1 Virus

    PubMed Central

    Morgan, Sophie B.; Hemmink, Johanneke D.; Porter, Emily; Harley, Ross; Shelton, Holly; Aramouni, Mario; Everett, Helen E.; Brookes, Sharon M.; Bailey, Michael; Townsend, Alain M.; Charleston, Bryan

    2016-01-01

    Influenza A viruses are a major health threat to livestock and humans, causing considerable mortality, morbidity, and economic loss. Current inactivated influenza vaccines are strain specific and new vaccines need to be produced at frequent intervals to combat newly arising influenza virus strains, so that a universal vaccine is highly desirable. We show that pandemic H1N1 influenza virus in which the hemagglutinin signal sequence has been suppressed (S-FLU), when administered to pigs by aerosol can induce CD4 and CD8 T cell immune responses in blood, bronchoalveolar lavage (BAL), and tracheobronchial lymph nodes. Neutralizing Ab was not produced. Detection of a BAL response correlated with a reduction in viral titer in nasal swabs and lungs, following challenge with H1N1 pandemic virus. Intratracheal immunization with a higher dose of a heterologous H5N1 S-FLU vaccine induced weaker BAL and stronger tracheobronchial lymph node responses and a lesser reduction in viral titer. We conclude that local cellular immune responses are important for protection against influenza A virus infection, that these can be most efficiently induced by aerosol immunization targeting the lower respiratory tract, and that S-FLU is a promising universal influenza vaccine candidate. PMID:27183611

  9. Design, Development and Test Challenges: Separation Mechanisms for the Orion Pad Abort-1 Flight Test

    NASA Technical Reports Server (NTRS)

    Dinsel, Alison; Morrey, Jeremy M.; OMalley, Patrick; Park, Samuel

    2011-01-01

    On May 6, 2010, NASA launched the first successful integrated flight test, Pad Abort-1, of the Orion Project from the White Sands Missile Range in Las Cruces, New Mexico. This test demonstrated the ability to perform an emergency pad abort of a full-scale 4.8 m diameter, 8200 kg crew capsule. During development of the critical separation mechanisms for this flight test, various challenges were overcome related to environments definition, installation complications, separation joint retraction speed, thruster ordnance development issues, load path validation and significant design loads increases. The Launch Abort System retention and release (LAS R&R) mechanism consisted of 6 discrete structural connections between the LAS and the crew module (CM) simulator, each of which had a preloaded tension tie, Superbolt torque-nut and frangible nut. During the flight test, the frangible nuts were pyrotechnically split, permitting the CM to separate from the LAS. The LAS separation event was the driving case in the shock environment for many co-located hardware items. During development testing, it was necessary to measure the source shock during the separation event so the predicted shock environment could be validated and used for certification testing of multiple hardware items. The Lockheed Martin test team measured the source separation shock due to the LAS R&R function, which dramatically decreased the predicted environment by 90% at 100 Hz. During development testing a hydraulic tensioner was used to preload the joint; however, the joint relaxation with the tensioner proved unsatisfactory so the design was modified to include a Superbolt torque-nut. The observed preload creep during lab testing was 4% after 30 days, with 2.5% occurring in the first 24 hours. The conversion of strain energy (preload) to kinetic energy (retraction) was measured to be 50-75%. Design features and careful monitoring of multiple strain gauges on each tension tie allowed a pure tensile load

  10. A Technical and Cost Perspective on Radiation Testing Challenges

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.; Cohen, Lewis M.

    2006-01-01

    A viewgraph presentation detailing costs and technical perspectives on radiation testing is shown. The topics include: 1) Introduction - a Changing Microelectronics World; 2) Sample Technology Changes and Related Impacts on Radiation Testing; 3) Perspective on the "New" Cost or Doing Business; and 4) Considerations.

  11. Characterizing particulate matter emissions from vehicles: chassis-dynamometer tests using a High-Resolution Aerosol Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Collier, S.; Zhang, Q.; Forestieri, S.; Kleeman, M.; Cappa, C. D.; Kuwayama, T.

    2012-12-01

    During September of 2011 a suite of real-time instruments was used to sample vehicle emissions at the California Air Resources Board Haagen-Schmidt facility in El Monte, CA. A representative fleet of 8 spark ignition gasoline vehicles, a diesel passenger vehicle, a gasoline direct-injection vehicle and an ultra-low emissions vehicle were tested on a chassis dynamometer. The emissions were sampled into the facility's standard CVS tunnel and diluted to atmospherically relevant levels (5-30 μg/m3) while controlling other factors such as relative humidity or background black carbon particulate loading concentrations. An Aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-MS) was among the real-time instruments used and sampled vehicle emissions at 10 second time resolution in order to characterize the non-refractory organic and inorganic particulate matter (PM). PM composition and concentration were tracked throughout the cold start driving cycle which included periods of fast acceleration and high velocity cruise control, meant to recreate typical commuter driving behavior. Variations in inorganic and organic PM composition for a given vehicle throughout the driving cycle as well as for various vehicles with differing emissions loading were characterized. Differences in PM composition for a given vehicle whose emissions are being exposed to differing experimental conditions such as varying relative humidity will also be reported. In conjunction with measurements from a Multi Wavelength Photoacoustic Black Carbon Spectrometer (MWPA-BC) and real-time gas measurements from the CARB facility, we determine the real-time emission ratios of primary organic aerosols (POA) with respect to BC and common combustion gas phase pollutants and compared to different vehicle driving conditions. The results of these tests offer the vehicle emissions community a first time glimpse at the real-time behavior of vehicle PM emissions for a variety of conditions and

  12. The Challenges of Meeting the "Standards": A Perspective from the Test Publishing Community

    ERIC Educational Resources Information Center

    Harris, William G.

    2006-01-01

    Some of the challenges that test publishers face in constructing educational assessments that meet high technical quality as prescribed in the "Standards for Educational and Psychological Testing" (AERA, APA, NCME, 1999) are examined. Federal educational initiatives are used to illustrate demands on technical quality that challenge the efforts of…

  13. FMIT test cell diagnostics3- A unique materials challenge

    NASA Astrophysics Data System (ADS)

    Cannon, C. P.; Fuller, J. L.

    Basic materials problems are discussed in instrumenting the FMIT test cell, which are applicable to fusion devices in general. Recent data on ceramic-to-metal seals, mineral insulated instrument cables, thermocouples, and optical components are reviewed. The data makes it clear that materials and instruments cannot be expected to behave in the FMIT test cell environment as they do in more familiar fission reactors and low power accelerators.

  14. Comparison of Controlled Field Test Aerosol Generation Devices to a Laboratory Device

    DTIC Science & Technology

    2013-11-01

    CHALLENGES WITH SIX PUFFERS........................................................ D-1 E . MAX COUNT READINGS REPORTED USING DETECTOR UNITS 1 AND 2 FOR...IJAG CHALLENGES .............................................. E -1 F. GRAPHICAL REPRESENTATION OF DETECTOR UNITS 1 AND 2 FOR IJAG CHALLENGES...detector, and it allows airflow through the region between its exhaust tube and the detector inlet tube. 2 The atomizer ( Aerogen ; Dangan, Galway

  15. Challenges in the Standardization of Autoantibody Testing: a Comprehensive Review.

    PubMed

    Tozzoli, Renato; Villalta, Danilo; Bizzaro, Nicola

    2016-08-08

    Standardization and harmonization are complementary tools to achieve higher testing quality in laboratory medicine. Both are of great relevance and are strongly needed in autoimmune diagnostics, due to the impressive advance in basic research and technological development observed in this diagnostic field in recent years that has led to the introduction of many new tests and new analytical methods. It is, therefore, essential that this strong innovative thrust is translated into clinical practice in a coordinated way to avoid confusion and the risk of potentially harmful errors for the patient. However, while standardization of antibody assays is a very complex task, harmonization of procedures and behaviors is a more feasible target and should necessarily include all the phases of the total testing process-in the pre-analytical phase, appropriateness of test requests, harmonization of autoantibody terminology, and adoption of uniform nomenclature for laboratory tests; in the analytical phase, harmonization of measurements, and sharing of test profiles and diagnostic algorithms; and in the post-analytical phase, harmonization of data reporting, and criteria for interpreting immunoserological results, especially harmonization of units, reference intervals, decision limits, and definition and notification of critical values. We here provide and discuss some examples of harmonization initiatives related to anti-nuclear antibodies, TSH receptor, and anti-thyroid peroxidase antibodies and to antibodies associated with autoimmune hepatitis and with celiac disease. These initiatives could be the starting steps to achieve a wider consensus and a closer interaction among stakeholders in the path of autoimmune diagnostics harmonization to enhance clinical effectiveness and provide greater patient safety.

  16. Cutaneous tuberculosis with nonreactive PPD skin test: a diagnostic challenge*

    PubMed Central

    Nassif, Priscila Wolf; Rosa, Ana Paula Zanatta; Gurgel, Ana Cristina Medeiros; Campanerut, Paula Aline Zanetti; Fillus Neto, José; Cardoso, Rosilene Fressatti

    2015-01-01

    The authors report a case of cutaneous tuberculosis in a 63-year-old female patient, who had an infiltrated, erythematous-ferruginous plaque of indurated aspect on her right leg and a nonreactive PPD skin test. Diagnosis was made by tissue culture and PCR of skin biopsy material. The treatment was performed with pyrazinamide, rifampicin, isoniazid and ethambutol, with good response. PMID:25672314

  17. Opting Out: Parents Creating Contested Spaces to Challenge Standardized Tests

    ERIC Educational Resources Information Center

    Mitra, Dana; Mann, Bryan; Hlavacik, Mark

    2016-01-01

    We explore how the opt-out movement has responded to the combination of a stringent federal policy with weak and often variable implementation among the states. Gaps between federal expectations and states' understandings of just how to make NCLB's demands a reality have created policy ambiguity. Parents who oppose standardized testing have…

  18. Promoting HIV testing proves to be a challenging subject.

    PubMed

    Herreria, J

    1998-01-01

    BGM, a Los Angeles-based advertising agency, has created a campaign for the Pediatrics AIDS Foundation to promote awareness of the importance of HIV testing of all pregnant women. The agency is taking a personal stake in the campaign by offering its services pro bono.

  19. SiO2 aerosol nanoparticle reactor for occupational health and safety studies.

    PubMed

    Ostraat, Michele L; Swain, Keith A; Krajewski, James J

    2008-06-01

    Important questions are emerging about potential occupational safety, toxicological, and ecotoxicological effects and occupational inhalation exposure risks to engineered aerosol nanoparticles. Although multiple avenues are available to synthesize nanoparticles, few tools are accessible to industrial hygienists and inhalation toxicologists to produce well-characterized aerosols of known aerosol size distribution and particle number concentration that are stable, simple, and robust to operate. This article describes a SiO(2) aerosol nanoparticle reactor that has been developed as a tool for the study of the safety, health, and environmental consequences of exposure to nanoparticle synthesis and processing. The SiO(2) aerosol nanoparticle reactor is capable of stable, long-term synthesis of amorphous SiO(2) aerosol nanoparticles from d(50) = 10-70 nm at particle concentrations approximately 10(4)-10(7)particles/cm(3) that does not produce halogen-containing byproducts and does not require daily monitoring of the particle size distribution. This reactor is designed to produce a well-characterized aerosol to enable subsequent testing with a continuous, stable supply of aerosol nanoparticles (i) to facilitate inhalation toxicology studies, (ii) to measure explosion characteristics of aerosol nanoparticles, (iii) to determine the barrier efficacy for respirator filtration, bag house exhaust, and personal protective garment media challenged with diverse aerosol nanoparticles, and (iv) to develop airborne monitoring technologies for verifying workplace safety protocols. This article details reactor design, synthesis parameters, and instruments available to characterize the resulting aerosol nanoparticle size distributions.

  20. PIP-II Injector Test: Challenges and Status

    SciTech Connect

    Derwent, P. F.; Carneiro, J. P.; Edelen, J.; Lebedev, V.; Prost, L.; Saini, A.; Shemyakin, A.; Steimel, J.

    2016-10-04

    The Proton Improvement Plan II (PIP-II) at Fermilab is a program of upgrades to the injection complex. At its core is the design and construction of a CW-compatible, pulsed H- superconducting RF linac. To validate the concept of the front-end of such machine, a test accelerator known as PIP-II Injector Test is under construction. It includes a 10mA DC, 30 keV H- ion source, a 2 m-long Low Energy Beam Transport (LEBT), a 2.1 MeV CW RFQ, followed by a Medium Energy Beam Transport (MEBT) that feeds the first of 2 cryomodules increasing the beam energy to about 25 MeV, and a High Energy Beam Transport section (HEBT) that takes the beam to a dump. The ion source, LEBT, RFQ, and initial version of the MEBT have been built, installed, and commissioned. This report presents the overall status of the Injector Test warm front end, including results of the beam commissioning through the installed components, and progress with SRF cryomodules and other systems.

  1. Design, fabrication and testing of ambient aerosol sampler inlets. Final report May 79-Oct 80

    SciTech Connect

    Wedding, J.B.; Weigand, M.A.

    1982-04-01

    Data are presented on the wind tunnel performances of two prototype Inhalable Particulate Matter (IPM) inlets designed for use with a dichotomous sampler. One was developed at the Aerosol Science Laboratory (ASL) Colorado State University, while the other was developed in an independent effort at the University of Minnesota (UM) and Lawrence Berkeley Laboratory (LBL). The ASL inlet is based on a unique omnidirectional cyclone fractionator, described in detail. Over the range of wind speeds from 0.5 - 24 km/hr, its measured 50% cutpoint was virtually invariant, 14.4 - 13.7 micrometers--well within the presently proposed IPM 50% cutpoint requirement. The UMLBL inlet results indicated near compliance with the IPM performance envelope, but there remain some small differences in data generated by UM and ASL personnel. Enrichment is apparent for both inlets in the 1 - 10 micrometers particle size range at the highest wind speed.

  2. Methodology for measuring exhaust aerosol size distributions using an engine test under transient operating conditions

    NASA Astrophysics Data System (ADS)

    María Desantes, José; Bermúdez, Vicente; Molina, Santiago; Linares, Waldemar G.

    2011-11-01

    A study on the sources of variability in the measurement of particle size distribution using a two-stage dilution system and an engine exhaust particle sizer was conducted to obtain a comprehensive and repeatable methodology that can be used to measure the particle size distribution of aerosols emitted by a light-duty diesel engine under transient operating conditions. The paper includes three experimental phases: an experimental validation of the measurement method; an evaluation of the influence of sampling factors, such as dilution system pre-conditioning; and a study of the effects of the dilution conditions, such as the dilution ratio and the dilution air temperature. An examination of the type and degree of influence of each studied factor is presented, recommendations for reducing variability are given and critical parameter values are identified to develop a highly reliable measurement methodology that could be applied to further studies on the effect of engine operating parameters on exhaust particle size distributions.

  3. Evaluation of antibiotic allergy: the role of skin tests and drug challenges.

    PubMed

    Solensky, Roland; Khan, David A

    2014-09-01

    Antibiotic allergies are frequently reported in both adult and pediatric populations. While a detailed drug history is essential in the evaluation of antibiotic allergy, the history is typically insufficient to determine the presence of a drug allergy. The most readily available diagnostic testing for evaluating antibiotic allergies are drug skin testing and drug challenges. This review will focus on updates in the evaluation of antibiotic allergy utilizing immediate skin tests, delayed intradermal testing, drug patch tests, and drug challenges for both adults and children with histories of antibiotic allergies.

  4. Effects of parabens and isothiazolinone on the microbiological quality of baby shampoo: the challenge test.

    PubMed

    Smaoui, Slim; Hlima, Hajer Ben

    2012-01-01

    An in vitro microbial challenge test has been developed to predict the likelihood of consumer contamination of baby shampoo. Four preservatives were tested in our study: the parbens Medcide D, Medcide PB, Sepicide HB. and isothiazolinone Methylisothiazolinone/Chloromethylisothiazolinone [MI/MCI]. These preservatives were tested separately and in combination. The challenge test involved inoculating the product with Micrococcus luteus, Staphylococcus aureus, Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Aspergillus brasiliensis and Candida albicans. Inhibition growth of these microorganisms at each preservative concentration was followed over a 28 d period. The test was used to classify products as poorly preserved, marginally preserved, or well-preserved. Interestingly, it was the combination (0.1% Isothiazolinone [MI/MCI] and 0.1% Sepicide HB) which inhibited most the microbial growth of microorganims while preserving the physicochemical properties of the product. As a result, the challenge test described can be accurately used to predict the risk of consumer contamination of cosmetic products.

  5. Challenger

    ERIC Educational Resources Information Center

    Allday, Jonathan

    2002-01-01

    The events that led to the spectacular destruction of the Space Shuttle "Challenger" in 1986 are detailed here. They show how NASA should have heeded engineers' worries over materials problems resulting from a launch in cold weather. Suggestions are made of how pupils could also learn from this tragedy. (Contains 4 figures and 2 footnotes.)

  6. Field test of a new instrument to measure UV/Vis (300-700 nm) ambient aerosol extinction spectra in Colorado during DISCOVER-AQ

    NASA Astrophysics Data System (ADS)

    Jordan, C. E.; Anderson, B. E.; Beyersdorf, A. J.; Dibb, J. E.; Greenslade, M. E.; Martin, R.; Scheuer, E. M.; Shook, M.; Thornhill, K. L., II; Troop, D.; Winstead, E.; Ziemba, L. D.

    2014-12-01

    An optical instrument has been developed to investigate aerosol extinction spectra in the ambient atmosphere. Based on a White-type cell design and using a differential optical approach, aerosol extinction spectra over the 300-700 nm ultraviolet and visible (UV/Vis) wavelength range are obtained. Laboratory tests conducted at NASA Langley Research Center (NASA LaRC) in March 2014 showed good agreement with Cavity Attenuated Phase Shift (CAPS PMex, Aerodyne Research) extinction measurements (at 450, 530, and 630 nm) for a variety of aerosols, e.g., scatterers such as polystyrene latex spheres and ammonium sulfate; absorbers such as dust (including pigmented minerals), smoke (generated in a miniCAST burning propane) and laboratory smoke analogs (e.g., fullerene soot and aquadag). The instrument was field tested in Colorado in July and August 2014 aboard the NASA mobile laboratory at various ground sites during the DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) field campaign. A description of the instrument, results from the laboratory tests, and summer field data will be presented. The instrument provides a new tool for probing in situ aerosol optical properties that may help inform remote sensing approaches well into the UV range.

  7. Increasing HIV testing among African immigrants in ireland: challenges and opportunities.

    PubMed

    Adedimeji, Adebola A; Asibon, Aba; O'Connor, Gerard; Carson, Richard; Cowan, Ethan; McKinley, Philip; Leider, Jason; Mallon, Patrick; Calderon, Yvette

    2015-02-01

    In 2012, immigrants constitute 63% of new cases of heterosexually transmitted HIV among individuals born outside Ireland. Current strategies to encourage testing can be ineffective if immigrants perceive them as culturally insensitive. We obtained qualitative data to explore challenges to voluntary HIV-testing for immigrants in Ireland. Content analysis was undertaken to identify and describe pertinent themes. Widespread beliefs that HIV is primarily a disease of African immigrants were identified as challenges that constrain access to testing and care. The organization and location of testing services, attitude of health workers, and beliefs regarding mandatory HIV-testing for immigrants seeking access to welfare benefits were also identified. Immigrants in Ireland encounter a variety of structural, cultural and personal constraints to HIV testing. Opportunities exist in the Irish Health system to increase testing among immigrants through greater acknowledgement of cultural sensitivities of immigrant groups.

  8. Challenges of Mating Disruption Using Aerosol-Emitting Pheromone Puffers in Red Clover Seed Production Fields to Control Coleophora deauratella (Lepidoptera: Coleophoridae).

    PubMed

    Mori, Boyd A; Evenden, Maya L

    2015-02-01

    Sex pheromone-mediated mating disruption using pheromone puffer dispensers was evaluated to control Coleophora deauratella (Lepidoptera: Coleophoridae) at three red clover seed production fields in Alberta, Canada. The objectives of the study were to determine aspects of the biology of C. deauratella which may affect successful mating disruption, evaluate the ability of aerosol-emitting pheromone puffers to reduce male moth catch in small-plot trials, and evaluate the ability of puffers to reduce male capture in traps, larval numbers and damage in large-plot trials. The median longevity of male and female C. deauratella was 6 d in the laboratory where males emerged in larger numbers earlier than females (protandry). Male response to pheromone peaked at sunrise; thus, puffers were programmed to dispense pheromone throughout this time period. Small-plot (0.25 ha) mating disruption trials indicated that pheromone released from puffers could reduce male C. deauratella orientation to traps by 60.7 ± 18.6% compared with that in untreated control plots. Reduction of male orientation to traps in large-plot (5 ha) trials over the course of the season was also successful (93.7 ± 1.6%). However, there was no corresponding decrease in larval numbers or increase in seed yield in pheromone-treated plots. Challenges of mating disruption of C. deauratella appear to be immigration of mated females combined with high population densities.

  9. Multifunctional, high-level cytokine-producing Th1 cells in the lung, but not spleen, correlate with protection against Mycobacterium tuberculosis aerosol challenge in mice.

    PubMed

    Forbes, Emily K; Sander, Clare; Ronan, Edward O; McShane, Helen; Hill, Adrian V S; Beverley, Peter C L; Tchilian, Elma Z

    2008-10-01

    Boosting bacillus Calmette-Guérin (BCG)-primed mice with a recombinant adenovirus expressing Mycobacterium tuberculosis Ag 85A by different administration routes has very different effects on protection against aerosol challenge with M. tuberculosis. Mice boosted intradermally make very strong splenic CD4 and CD8 Th1 cytokine responses to Ag 85A, but show no change in lung mycobacterial burden over BCG primed animals. In contrast, intranasally boosted mice show greatly reduced mycobacterial burden and make a much weaker splenic response but a very strong lung CD4 and CD8 response to Ag 85A and an increased response to purified protein derivative. This effect is associated with the presence in the lung of multifunctional T cells, with high median fluorescence intensity and integrated median fluorescence intensity for IFN-gamma, IL-2, and TNF. In contrast, mice immunized with BCG alone have few Ag-specific cells in the lung and a low proportion of multifunctional cells, although individual cells have high median fluorescence intensity. Successful immunization regimes appear to induce Ag-specific cells with abundant intracellular cytokine staining.

  10. Repeated Challenge Studies: A Comparison of Union-Intersection Testing with Linear Modeling.

    ERIC Educational Resources Information Center

    Levine, Richard A.; Ohman, Pamela A.

    1997-01-01

    Challenge studies can be used to see whether there is a causal relationship between an agent of interest and a response. An approach based on union-intersection testing is presented that allows researchers to examine observations on a single subject and test the hypothesis of interest. An application using psychological data is presented. (SLD)

  11. Advanced Electronics Technologies: Challenges for Radiation Effects Testing, Modeling, and Mitigation

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.; Cohn, Lewis M.

    2005-01-01

    Emerging Electronics Technologies include: 1) Changes in the commercial semiconductor world; 2) Radiation Effects Sources (A sample test constraint); and 3) Challenges to Radiation Testing and Modeling: a) IC Attributes-Radiation Effects Implication b) Fault Isolation c) Scaled Geometry d) Speed e) Modeling Shortfall f) Knowledge Status

  12. Radiation Testing on State-of-the-Art CMOS: Challenges, Plans, and Preliminary Results

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.; Cohn, Lewis M.

    2009-01-01

    At GOMAC 2007 and 2008, we discussed a variety of challenges for radiation testing of modern semiconductor devices and technologies [1, 2]. In this presentation, we provide more specific details in this on-going investigation focusing on out-of-the-box lessons observed for providing radiation effects assurances as well as preliminary test results.

  13. The challenge of developmentally appropriate care: predictive genetic testing in young people for familial adenomatous polyposis.

    PubMed

    Duncan, Rony E; Gillam, Lynn; Savulescu, Julian; Williamson, Robert; Rogers, John G; Delatycki, Martin B

    2010-03-01

    Predictive genetic tests for familial adenomatous polyposis (FAP) are routinely offered to young people during early adolescence. While this is not controversial, due to the medical benefit conferred by the test, it is nonetheless challenging as a consequence of the stage of life of the young people, and the simultaneous involvement of multiple family members. Despite these challenges, it is possible to ensure that the test is offered in such a way that it actively acknowledges and facilitates young people's developing autonomy and psychosocial well-being. In this paper we present findings from ten in-depth interviews with young people who have undergone predictive genetic testing for FAP (four male, six female; five gene-positive, five gene-negative; aged 10-17 years at the time of their predictive test; aged 12-25 years at the time of their research interview). We present five themes that emerged from the interviews which highlight key ethical challenges associated with such testing. These are: (1) the significance of the test; (2) young people's lack of involvement in the decision to be tested; (3) young people's limited understanding; (4) provision of the blood test at the first visit; and (5) group testing of family members. We draw on these themes to make eight recommendations for future practice. Together, these recommendations highlight the importance of providing developmentally appropriate care to young people undergoing predictive genetic testing for FAP.

  14. A TEST OF THERMODYNAMIC EQUILIBRIUM MODELS AND 3-D AIR QUALITY MODELS FOR PREDICTIONS OF AEROSOL NO3-

    EPA Science Inventory

    The inorganic species of sulfate, nitrate and ammonium constitute a major fraction of atmospheric aerosols. The behavior of nitrate is one of the most intriguing aspects of inorganic atmospheric aerosols because particulate nitrate concentrations depend not only on the amount of ...

  15. Measured In Situ Atmospheric Ambient Aerosol Size-Distributions, Particle Concentrations, and Turbulence Data for RSA TA-6 Test Range, Redstone Arsenal, AL, April-May 2015

    DTIC Science & Technology

    2015-09-01

    Concentrations, and Turbulence Data for RSA TA-6 Test Range, Redstone Arsenal , AL, April–May 2015 by Kristan Gurton, Stephanie Cunningham, and...Aerosol Size-Distributions, Particle Concentrations, and Turbulence Data for RSA TA-6 Test Range, Redstone Arsenal , AL, April–May 2015 by Kristan...Redstone Arsenal , AL Approved for public release; distribution unlimited. ii REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188

  16. Safety Testing of Dengue-1 and Dengue-3 Seeds for Human Challenges, Unattenuated

    DTIC Science & Technology

    1987-03-16

    62770A870 AC 029 11. TITL.E (Include Security Classiftcation) (U) Safety Testing of Dengue -1 and Dengue -𔃽 Seeds for Human Challenges, Unatteuad 12...safety testing of a lot of dengue virus type 3 designated as: Dengue Virus Type 3 (Non-Attenuated) Strain CH-53489 Utilizing the testing procedures...Virus Strain: Dengue Virus *rype 3 (Non-Attenuated) Strain: CH-53489 B. Live Virus Vaccine Pool Designation: MFG Date: April J.984, LOT No. 1 C

  17. Liposomal aerosols in the management of pulmonary infections.

    PubMed

    Gilbert, B E

    1996-01-01

    The combination of liposomes and aerosols has been utilized to directly target the lungs with chemotherapeutic agents that might not have been used because of low solubility or toxicity. There are a variety of antibacterials, antifungals, and antivirals that have good in vitro activity, but are not effective because of their systemic toxicity and/or poor penetration into the lungs. Incorporation of many lipophilic drugs into liposomes decreases their toxicity without affecting effectiveness, thus increasing the therapeutic index. We have focused on aerosol delivery of amphotericin B (ampB) for the treatment of pulmonary and systemic fungal diseases. We have tested a variety of ampB-lipid formulations for the optimal treatment regimen for Cryptococcus and Candida infections in mouse models. The AeroTech II nebulizer (MMADs of 1.8-2.2 microns) produced aerosols with the highest concentrations in the breathable range. Pharmacokinetic studies revealed that pulmonary drug was present for hours to weeks. AmBisome retained its anticryptococcal activity even when animals were challenged 14 days after aerosol treatment. Aerosols may also be effective in systemic diseases. In our Candida-mouse model, systemic candidiasis and mortality were reduced by aerosolized ampB-liposome treatment. The ability to utilize lipophilic drugs, to deliver high concentrations of drug directly to the site of infection, and to reduce toxicity makes aerosol liposomes an attractive, alternative route of administration.

  18. The Test Analysis Retrieval System (TARS): Meeting the challenges of the network's test processes

    NASA Technical Reports Server (NTRS)

    Stelmaszek, Robert L.; Lumsden, Douglas R.

    1993-01-01

    The Networks Systems Test Section (GSFC 531.4) is responsible for managing a variety of engineering and operational tests used to assess the status of the Network elements relative to readiness certification for new and ongoing mission support and for performance trending. To conduct analysis of data collected during these tests, to disseminate and share the information, and to catalog and create reports based on the analysis is currently a cumbersome and inefficient task due primarily to the manual handling of paper products and the inability to easily exchange information between the various Networks elements. The Test Analysis and Retrieval System (TARS) is being implemented to promote concise data analysis, intelligible reporting of test results, to minimize test duplication by fostering a broad sharing of test data, and perhaps most importantly, to provide significantly improved response to the Network's internal and external customers. This paper outlines the intended application, architecture, and benefits of the TARS.

  19. Organic aerosols

    SciTech Connect

    Penner, J.E.

    1994-01-01

    Organic aerosols scatter solar radiation. They may also either enhance or decrease concentrations of cloud condensation nuclei. This paper summarizes observed concentrations of aerosols in remote continental and marine locations and provides estimates for the sources of organic aerosol matter. The anthropogenic sources of organic aerosols may be as large as the anthropogenic sources of sulfate aerosols, implying a similar magnitude of direct forcing of climate. The source estimates are highly uncertain and subject to revision in the future. A slow secondary source of organic aerosols of unknown origin may contribute to the observed oceanic concentrations. The role of organic aerosols acting as cloud condensation nuclei (CCN) is described and it is concluded that they may either enhance or decrease the ability of anthropogenic sulfate aerosols to act as CCN.

  20. SUBMERGED GRAVEL SCRUBBER DEMONSTRATION AS A PASSIVE AIR CLEANER FOR CONTAINMENT VENTING AND PURGING WITH SODIUM AEROSOLS -- CSTF TESTS AC7 - AC10

    SciTech Connect

    HILLIARD, R K.; MCCORMACK, J D.; POSTMA, A K.

    1981-11-01

    Four large-scale air cleaning tests (AC7 - AC10) were performed in the Containment Systems Test Facility (CS'lF) to demonstrate the performance of a Submerged Gravel Scrubber for cleaning the effluent gas from a vented and purged breeder reactor containment vessel. The test article, comprised of a Submerged Gravel Scrubber (SGS) followed by a high efficiency fiber demister, had a design gas flow rate of 0.47 m{sup 3}/s (1000 ft{sup 3}/min) at a pressure drop of 9.0 kPa (36 in. H{sub 2}O). The test aerosol was sodium oxide, sodium hydroxide, or sodium carbonate generated in the 850-m{sup 3} CSTF vessel by continuously spraying sodium into the air-filled vessel while adding steam or carbon dioxide. Approximately 4500 kg (10,000 lb) of sodium was sprayed over a total period of 100 h during the tests. The SGS/Demister system was shown to be highly efficient (removing ~99.98% of the entering sodium aerosol mass), had a high mass loading capacity, and operated in a passive manner, with no electrical requirement. Models for predicting aerosol capture, gas cooling, and pressure drop are developed and compared with experimental results.

  1. 40 CFR 53.59 - Aerosol transport test for Class I equivalent method samplers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II... generator according to conventions specified in § 53.61(g). (ii) Check for the presence of satellites...

  2. Adenosine dry powder inhalation for bronchial challenge testing, part 2: proof of concept in asthmatic subjects.

    PubMed

    Lexmond, Anne J; van der Wiel, Erica; Hagedoorn, Paul; Bult, Wouter; Frijlink, Henderik W; ten Hacken, Nick H T; de Boer, Anne H

    2014-09-01

    Adenosine is an indirect stimulus to assess bronchial hyperresponsiveness (BHR(2)) in asthma. Bronchial challenge tests are usually performed with nebulised solutions of adenosine 5'-monophosphate (AMP(3)). The nebulised AMP test has several disadvantages, like long administration times and a restrictive maximum concentration that does not result in BHR in all patients. In this study, we investigated the applicability of dry powder adenosine for assessment of BHR in comparison to nebulised AMP. Dry powder adenosine was prepared in doubling doses (0.01-80 mg) derived from the nebulised AMP test with addition of two higher doses. Five asthmatic subjects performed two bronchial challenge tests, one with nebulised AMP following the 2-min tidal breathing method; the second with dry powder adenosine administered with an investigational inhaler and single slow inhalations (inspiratory flow rate 30-40 L/min). All subjects reached a 20% fall in FEV₁(4) with the new adenosine test (PD20(5)) compared to four subjects with the AMP test (PC₂₀(6)). Dry powder adenosine was well tolerated by all subjects and better appreciated than nebulised AMP. In conclusion, this new bronchial challenge test appears to be a safe and convenient alternative to the nebulised AMP test to assess BHR in asthmatic subjects.

  3. Phenols and hydroxy-PAHs (arylphenols) as tracers for coal smoke particulate matter: source tests and ambient aerosol assessments

    SciTech Connect

    Bernd R.T. Simoneit; Xinhui Bi; Daniel R. Oros; Patricia M. Medeiros; Guoying Sheng; Jiamo Fu

    2007-11-01

    Source tests were conducted to analyze and characterize diagnostic key tracers for emissions from burning of coals with various ranks. Coal samples included lignite from Germany, semibituminous coal from Arizona, USA, bituminous coal from Wales, UK and sample from briquettes of semibituminous coal, bituminous coal and anthracite from China. Ambient aerosol particulate matter was also collected in three areas of China and a background area in Corvallis, OR (U.S.) to confirm the presence of tracers specific for coal smoke. The results showed a series of aliphatic and aromatic hydrocarbons and phenolic compounds, including PAHs and hydroxy-PAHs as the major tracers, as well as a significant unresolved complex mixture (UCM) of compounds. The tracers that were found characteristic of coal combustion processes included hydroxy-PAHs and PAHs. Atmospheric ambient samples from Beijing and Taiyuan, cities where coal is burned in northern China, revealed that the hydroxy-PAH tracers were present during the wintertime, but not in cities where coal is not commonly used (e.g., Guangzhou, South China). Thus, the mass of hydroxy-PAHs can be apportioned to coal smoke and the source strength modeled by summing the proportional contents of EC (elemental carbon), PAHs, UCM and alkanes with the hydroxy-PAHs. 36 refs., 2 figs., 3 tabs.

  4. CONTINUED DEVELOPMENT AND TESTING OF A NEW THERMODYNAMIC AEROSOL MODULE FOR URBAN AND REGIONAL AIR QUALITY MODELS. (R824793)

    EPA Science Inventory

    A computationally efficient and rigorous thermodynamic model (ISORROPIA) that predicts the physical state and composition of inorganic atmospheric aerosol is presented. The advantages of this particular model render it suitable for incorporation into urban and regional air qualit...

  5. Evaluations of cirrus contamination and screening in ground aerosol observations using collocated lidar systems

    NASA Astrophysics Data System (ADS)

    Huang, Jingfeng; Hsu, N. Christina; Tsay, Si-Chee; Holben, Brent N.; Welton, Ellsworth J.; Smirnov, Alexander; Jeong, Myeong-Jae; Hansell, Richard A.; Berkoff, Timothy A.; Liu, Zhaoyan; Liu, Gin-Rong; Campbell, James R.; Liew, Soo Chin; Barnes, John E.

    2012-08-01

    Cirrus clouds, particularly subvisual high thin cirrus with low optical thickness, are difficult to screen in operational aerosol retrieval algorithms. Collocated aerosol and cirrus observations from ground measurements, such as the Aerosol Robotic Network (AERONET) and the Micro-Pulse Lidar Network (MPLNET), provide us with an unprecedented opportunity to systematically examine the susceptibility of operational aerosol products to cirrus contamination. Quality assured aerosol optical thickness (AOT) measurements were also tested against the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) vertical feature mask (VFM) and the Moderate Resolution Imaging Spectroradiometer (MODIS) thin cirrus screening parameters for the purpose of evaluating cirrus contamination. Key results of this study include: (1) quantitative evaluations of data uncertainties in AERONET AOT retrievals are conducted; although AERONET cirrus screening schemes are successful in removing most cirrus contamination, strong residuals displaying strong spatial and seasonal variability still exist, particularly over thin cirrus prevalent regions during cirrus peak seasons; (2) challenges in matching up different data for analysis are highlighted and corresponding solutions proposed; and (3) estimates of the relative contributions from cirrus contamination to aerosol retrievals are discussed. The results are valuable for better understanding and further improving ground aerosol measurements that are critical for aerosol-related climate research.

  6. New challenges for BRCA testing: a view from the diagnostic laboratory

    PubMed Central

    Wallace, Andrew J

    2016-01-01

    Increased demand for BRCA testing is placing pressures on diagnostic laboratories to raise their mutation screening capacity and handle the challenges associated with classifying BRCA sequence variants for clinical significance, for example interpretation of pathogenic mutations or variants of unknown significance, accurate determination of large genomic rearrangements and detection of somatic mutations in DNA extracted from formalin-fixed, paraffin-embedded tumour samples. Many diagnostic laboratories are adopting next-generation sequencing (NGS) technology to increase their screening capacity and reduce processing time and unit costs. However, migration to NGS introduces complexities arising from choice of components of the BRCA testing workflow, such as NGS platform, enrichment method and bioinformatics analysis process. An efficient, cost-effective accurate mutation detection strategy and a standardised, systematic approach to the reporting of BRCA test results is imperative for diagnostic laboratories. This review covers the challenges of BRCA testing from the perspective of a diagnostics laboratory. PMID:27514839

  7. Radiation Testing, Characterization and Qualification Challenges for Modern Microelectronics and Photonics Devices and Technologies

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.; Cohn, Lewis M.

    2008-01-01

    At an earlier conference we discussed a selection of the challenges for radiation testing of modern semiconductor devices focusing on state-of-the-art CMOS technologies. In this presentation, we extend this discussion focusing on the following areas: (1) Device packaging, (2) Evolving physical single even upset mechanisms, (3) Device complexity, and (4) the goal of understanding the limitations and interpretation of radiation testing results.

  8. Identifying System Patterns to Resolve Challenges in the Test and Evaluation Operation

    DTIC Science & Technology

    2013-03-01

    parameters, and determines whether systems are operationally effective , suitable, survivable, and safe for intended use. This directive mandates the... effectiveness and operational suitability of a system under realistic operational conditions, including joint combat operations; determines the...test plan and data collected and analyzed which leads to an assessment of system performance and effectiveness characteristics. Challenges

  9. Integration and Testing Challenges of Small, Multiple Satellite Missions: Experiences From The Space Technology 5 Project

    NASA Technical Reports Server (NTRS)

    Sauerwein, Timothy A.; Gostomski, Thomas

    2007-01-01

    This brief presentation describes the mechanical and electrical integration activities and environmental testing challenges of the Space Technology 5 (ST5) Project. Lessons learned during this process are highlighted, including performing mechanical activities serially to gain efficiency through repetition and performing electrical activities based on the level of subsystem expertise available.

  10. Inversion of the anomalous diffraction approximation for variable complex index of refraction near unity. [numerical tests for water-haze aerosol model

    NASA Technical Reports Server (NTRS)

    Smith, C. B.

    1982-01-01

    The Fymat analytic inversion method for retrieving a particle-area distribution function from anomalous diffraction multispectral extinction data and total area is generalized to the case of a variable complex refractive index m(lambda) near unity depending on spectral wavelength lambda. Inversion tests are presented for a water-haze aerosol model. An upper-phase shift limit of 5 pi/2 retrieved an accurate peak area distribution profile. Analytical corrections using both the total number and area improved the inversion.

  11. Direct-field acoustic testing of a flight system : logistics, challenges, and results.

    SciTech Connect

    Stasiunas, Eric Carl; Gurule, David Joseph; Babuska, Vit; Skousen, Troy J.

    2010-10-01

    Before a spacecraft can be considered for launch, it must first survive environmental testing that simulates the launch environment. Typically, these simulations include vibration testing performed using an electro-dynamic shaker. For some spacecraft however, acoustic excitation may provide a more severe loading environment than base shaker excitation. Because this was the case for a Sandia Flight System, it was necessary to perform an acoustic test prior to launch in order to verify survival due to an acoustic environment. Typically, acoustic tests are performed in acoustic chambers, but because of scheduling, transportation, and cleanliness concerns, this was not possible. Instead, the test was performed as a direct field acoustic test (DFAT). This type of test consists of surrounding a test article with a wall of speakers and controlling the acoustic input using control microphones placed around the test item, with a closed-loop control system. Obtaining the desired acoustic input environment - proto-flight random noise input with an overall sound pressure level (OASPL) of 146.7 dB-with this technique presented a challenge due to several factors. An acoustic profile with this high OASPL had not knowingly been obtained using the DFAT technique prior to this test. In addition, the test was performed in a high-bay, where floor space and existing equipment constrained the speaker circle diameter. And finally, the Flight System had to be tested without contamination of the unit, which required a contamination bag enclosure of the test unit. This paper describes in detail the logistics, challenges, and results encountered while performing a high-OASPL, direct-field acoustic test on a contamination-sensitive Flight System in a high-bay environment.

  12. Testing for Accountability: A Balancing Act That Challenges Current Testing Practices and Theories

    ERIC Educational Resources Information Center

    Brennan, Robert L.

    2015-01-01

    Koretz, in his article published in this issue, provides compelling arguments that the high stakes currently associated with accountability testing lead to behavioral changes in students, teachers, and other stakeholders that often have negative consequences, such as inflated scores. Koretz goes on to argue that these negative consequences require…

  13. Challenges of Cold Conditioning and Static Testing the Second Ares Demonstration Motor (DM-2)

    NASA Technical Reports Server (NTRS)

    Quinn, Shyla; Davis, Larry C.

    2011-01-01

    On August 31, 2010, a five-segment demonstration motor (DM) for the Ares program was successfully tested. A series of demonstration motors (DMs) will be tested in different conditioned environments to confirm they meet their design specifications. The second demonstration motor (DM-2) was the first cold motor. The motor needed to be subjected to sub-freezing temperatures for two months so that its internal propellant mean bulk temperature (PMBT) was approximately 40 F. Several challenges had to be overcome to make this a successful test. One challenge was to condition four field joints to get the O-rings approximately 32 F. This would be done by applying conditioning shrouds to externally cool each field joint after the test bay was pulled off. The purpose of this conditioning was to validate the new O-ring design and allow joint heaters to be eliminated. Another challenge was maintaining temperature requirements for components in the nozzle vectoring system. A separate heating system was used to warm these components during cold conditioning. There were 53 test objectives that required 764 channels of data to be recorded; 460 were specific to DM-2. This instrumentation had to be installed prior to conditioning, which meant the baseline process and timeline had to be modified to meet this time critical schedule.

  14. Modeling and design of challenge tests: Inflammatory and metabolic biomarker study examples.

    PubMed

    Gabrielsson, Johan; Hjorth, Stephan; Vogg, Barbara; Harlfinger, Stephanie; Gutierrez, Pablo Morentin; Peletier, Lambertus; Pehrson, Rikard; Davidsson, Pia

    2015-01-25

    Given the complexity of pharmacological challenge experiments, it is perhaps not surprising that design and analysis, and in turn interpretation and communication of results from a quantitative point of view, is often suboptimal. Here we report an inventory of common designs sampled from anti-inflammatory, respiratory and metabolic disease drug discovery studies, all of which are based on animal models of disease involving pharmacological and/or patho/physiological interaction challenges. The corresponding data are modeled and analyzed quantitatively, the merits of the respective approach discussed and inferences made with respect to future design improvements. Although our analysis is limited to these disease model examples, the challenge approach is generally applicable to the vast majority of pharmacological intervention studies. In the present five Case Studies results from pharmacodynamic effect models from different therapeutic areas were explored and analyzed according to five typical designs. Plasma exposures of test compounds were assayed by either liquid chromatography/mass spectrometry or ligand binding assays. To describe how drug intervention can regulate diverse processes, turnover models of test compound-challenger interaction, transduction processes, and biophase time courses were applied for biomarker response in eosinophil count, IL6 response, paw-swelling, TNFα response and glucose turnover in vivo. Case Study 1 shows results from intratracheal administration of Sephadex, which is a glucocorticoid-sensitive model of airway inflammation in rats. Eosinophils in bronchoalveolar fluid were obtained at different time points via destructive sampling and then regressed by the mixed-effects modeling. A biophase function of the Sephadex time course was inferred from the modeled eosinophil time courses. In Case Study 2, a mouse model showed that the time course of cytokine-induced IL1β challenge was altered with or without drug intervention. Anakinra

  15. ATI TDA 5A aerosol generator evaluation

    SciTech Connect

    Gilles, D.A.

    1998-07-27

    Oil based aerosol ``Smoke`` commonly used for testing the efficiency and penetration of High Efficiency Particulate Air filters (HEPA) and HEPA systems can produce flammability hazards that may not have been previously considered. A combustion incident involving an aerosol generator has caused an investigation into the hazards of the aerosol used to test HEPA systems at Hanford.

  16. Development of a national EUCAST challenge panel for antimicrobial susceptibility testing.

    PubMed

    Desmet, S; Verhaegen, J; Glupzcynski, Y; Van Eldere, J; Melin, P; Goossens, H; Piérard, D; Declercq, P; Lagrou, K; Boel, A; Cartuyvels, R; Denis, O; Vandewal, W; Saegeman, V

    2016-08-01

    A challenge panel of bacterial strains useful for clinical laboratories to validate their European Committee on Antimicrobial Susceptibility Testing (EUCAST) antimicrobial susceptibility test (AST) system was established. A total of 117 strains, obtained from Belgian Reference Centres (n = 57) and from routine clinical samples (n = 60) was selected based on resistance pattern. These strains were analysed in seven different laboratories by three different automated AST systems (Vitek (n = 2), Phoenix (n = 2) and Microscan (n = 2)) and by disc diffusion from five different manufacturers (Rosco (n = 2), Becton-Dickinson (n = 2), Biomérieux (n = 1), Bio-rad (n = 1) and i2a (n = 1)). To select the challenge panel, selection criteria were set for categorical agreement between the different systems and the number of very major errors, major errors and minor errors. Very major and major errors for at least two antibiotics were observed in 43% of all strains, leading to the exclusion of these strains from the selected panel. In only 10% of all tested strains was there 100% categorical agreement for all antibiotics. Finally, 28 strains (14 Gram-positive and 14 Gram-negative) covering a wide spectrum of resistance mechanisms were selected. Pilot-testing of this challenge panel in 20 laboratories mainly confirmed the results of the validation study. Only six strains withheld for the pilot study could not be used as challenge strain due to an overall (very) major error rate of >5% for a particular antibiotic (n = 5) or for two antibiotics (n = 1). To conclude, this challenge panel should facilitate the implementation and use of EUCAST breakpoints in laboratories.

  17. African American church-based HIV testing and linkage to care: assets, challenges and needs.

    PubMed

    Stewart, Jennifer M; Thompson, Keitra; Rogers, Christopher

    2016-01-01

    The US National HIV AIDS strategy promotes the use of faith communities to lessen the burden of HIV in African American communities. One specific strategy presented is the use of these non-traditional venues for HIV testing and co-location of services. African American churches can be at the forefront of this endeavour through the provision of HIV testing and linkage to care. However, there are few interventions to promote the churches' involvement in both HIV testing and linkage to care. We conducted 4 focus groups (n = 39 participants), 4 interviews and 116 surveys in a mixed-methods study to examine the feasibility of a church-based HIV testing and linkage to care intervention in Philadelphia, PA, USA. Our objectives were to examine: (1) available assets, (2) challenges and barriers and (3) needs associated with church-based HIV testing and linkage to care. Analyses revealed several factors of importance, including the role of the church as an access point for testing in low-income neighbourhoods, challenges in openly discussing the relationship between sexuality and HIV, and buy-in among church leadership. These findings can support intervention development and necessitate situating African American church-based HIV testing and linkage to care interventions within a multi-level framework.

  18. Advancing Models and Evaluation of Cumulus, Climate and Aerosol Interactions

    SciTech Connect

    Gettelman, Andrew

    2015-10-27

    This project was successfully able to meet its’ goals, but faced some serious challenges due to personnel issues. Nonetheless, it was largely successful. The Project Objectives were as follows: 1. Develop a unified representation of stratifom and cumulus cloud microphysics for NCAR/DOE global community models. 2. Examine the effects of aerosols on clouds and their impact on precipitation in stratiform and cumulus clouds. We will also explore the effects of clouds and precipitation on aerosols. 3. Test these new formulations using advanced evaluation techniques and observations and release

  19. Validation of Alternative In Vitro Methods to Animal Testing: Concepts, Challenges, Processes and Tools.

    PubMed

    Griesinger, Claudius; Desprez, Bertrand; Coecke, Sandra; Casey, Warren; Zuang, Valérie

    This chapter explores the concepts, processes, tools and challenges relating to the validation of alternative methods for toxicity and safety testing. In general terms, validation is the process of assessing the appropriateness and usefulness of a tool for its intended purpose. Validation is routinely used in various contexts in science, technology, the manufacturing and services sectors. It serves to assess the fitness-for-purpose of devices, systems, software up to entire methodologies. In the area of toxicity testing, validation plays an indispensable role: "alternative approaches" are increasingly replacing animal models as predictive tools and it needs to be demonstrated that these novel methods are fit for purpose. Alternative approaches include in vitro test methods, non-testing approaches such as predictive computer models up to entire testing and assessment strategies composed of method suites, data sources and decision-aiding tools. Data generated with alternative approaches are ultimately used for decision-making on public health and the protection of the environment. It is therefore essential that the underlying methods and methodologies are thoroughly characterised, assessed and transparently documented through validation studies involving impartial actors. Importantly, validation serves as a filter to ensure that only test methods able to produce data that help to address legislative requirements (e.g. EU's REACH legislation) are accepted as official testing tools and, owing to the globalisation of markets, recognised on international level (e.g. through inclusion in OECD test guidelines). Since validation creates a credible and transparent evidence base on test methods, it provides a quality stamp, supporting companies developing and marketing alternative methods and creating considerable business opportunities. Validation of alternative methods is conducted through scientific studies assessing two key hypotheses, reliability and relevance of the

  20. Inversion of solar extinction data from the Apollo-Soyuz Test Project Stratospheric Aerosol Measurement (ASTP/SAM) experiment

    NASA Technical Reports Server (NTRS)

    Pepin, T. J.

    1977-01-01

    The inversion methods are reported that have been used to determine the vertical profile of the extinction coefficient due to the stratospheric aerosols from data measured during the ASTP/SAM solar occultation experiment. Inversion methods include the onion skin peel technique and methods of solving the Fredholm equation for the problem subject to smoothing constraints. The latter of these approaches involves a double inversion scheme. Comparisons are made between the inverted results from the SAM experiment and near simultaneous measurements made by lidar and balloon born dustsonde. The results are used to demonstrate the assumptions required to perform the inversions for aerosols.

  1. Having Fun and Accepting Challenges Are Natural Instincts: Jigsaw Puzzles to Challenge Students and Test Their Abilities While Having Fun!

    ERIC Educational Resources Information Center

    Rodenbaugh, Hanna R.; Lujan, Heidi L.; Rodenbaugh, David W.; DiCarlo, Stephen E.

    2014-01-01

    Because jigsaw puzzles are fun, and challenging, students will endure and discover that persistence and grit are rewarded. Importantly, play and fun have a biological place just like sleep and dreams. Students also feel a sense of accomplishment when they have completed a puzzle. Importantly, the reward of mastering a challenge builds confidence…

  2. [Utility of challenge test in immediate hypersensitivity to hydrocortisone sodium succinate].

    PubMed

    Amaya-Mejía, Adela Sisy; Galindo-Pacheco, Lucy Vania; O'Farrill-Romanillos, Patricia María; Rodríguez-Mireles, Karen Alicia; Campos-Romero, Freya Helena; del Rivero-Hernández, Leonel

    2014-01-01

    Corticosteroid hypersensitivity is a complex phenomenon in which many factors interact, such as idiosyncrasy, intolerance or allergic reactions. The prevalence of immediate hypersensitivity reactions to corticosteroids is 0.2%-0.5%. Corticosteroids have major therapeutic implications; thus, when hypersensitivity is suspected, in-vitro and/or in-vivo testing can be performed to confirm diagnosis, being the drug challenge the gold standard. After definitive diagnosis, cross-reactivity among the different corticosteroid groups should be considered, to choose wisely if corticosteroid therapy is still required. In Coopman classification, steroids belonging to groups A, B and D2 have high cross-reactivity, however, more studies are needed to determine the degree of cross-reaction among these drugs. This paper presents the case of a woman, in who hypersensitivity to hydrocortisone succinate was confirmed by drug challenge test.

  3. Comparative antimicrobial activities of aerosolized sodium hypochlorite, chlorine dioxide, and electrochemically activated solutions evaluated using a novel standardized assay.

    PubMed

    Thorn, R M S; Robinson, G M; Reynolds, D M

    2013-05-01

    The main aim of this study was to develop a standardized experimental assay to enable differential antimicrobial comparisons of test biocidal aerosols. This study represents the first chlorine-matched comparative assessment of the antimicrobial activities of aerosolized sodium hypochlorite, chlorine dioxide, and electrochemically activated solution (ECAS) to determine their relative abilities to decontaminate various surface-associated health care-relevant microbial challenges. Standard microbiological challenges were developed by surface-associating typed Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis spores, or a clinical methicillin-resistant S. aureus (MRSA) strain on stainless steel, polypropylene, or fabric. All test coupons were subjected to 20-min biocidal aerosols of chlorine-matched (100 ppm) sodium hypochlorite, chlorine dioxide, or ECAS within a standard aerosolization chamber using a commercial humidifier under defined conditions. Biocidal treatment type and material surface had a significant effect on the number of microorganisms recovered from various material surfaces following treatment exposure. Under the conditions of the assay, the order of antimicrobial efficacy of biocidal aerosol treatment was as follows: ECAS > chlorine dioxide > sodium hypochlorite. For all biocides, greater antimicrobial reductions were seen when treating stainless steel and fabric than when treating plastic-associated microorganisms. The experimental fogging system and assay protocol designed within this study were shown capable of differentiating the comparative efficacies of multiple chlorine-matched biocidal aerosols against a spectrum of target organisms on a range of test surface materials and would be appropriate for testing other biocidal aerosol treatments or material surfaces.

  4. Comparative Antimicrobial Activities of Aerosolized Sodium Hypochlorite, Chlorine Dioxide, and Electrochemically Activated Solutions Evaluated Using a Novel Standardized Assay

    PubMed Central

    Thorn, R. M. S.; Robinson, G. M.

    2013-01-01

    The main aim of this study was to develop a standardized experimental assay to enable differential antimicrobial comparisons of test biocidal aerosols. This study represents the first chlorine-matched comparative assessment of the antimicrobial activities of aerosolized sodium hypochlorite, chlorine dioxide, and electrochemically activated solution (ECAS) to determine their relative abilities to decontaminate various surface-associated health care-relevant microbial challenges. Standard microbiological challenges were developed by surface-associating typed Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis spores, or a clinical methicillin-resistant S. aureus (MRSA) strain on stainless steel, polypropylene, or fabric. All test coupons were subjected to 20-min biocidal aerosols of chlorine-matched (100 ppm) sodium hypochlorite, chlorine dioxide, or ECAS within a standard aerosolization chamber using a commercial humidifier under defined conditions. Biocidal treatment type and material surface had a significant effect on the number of microorganisms recovered from various material surfaces following treatment exposure. Under the conditions of the assay, the order of antimicrobial efficacy of biocidal aerosol treatment was as follows: ECAS > chlorine dioxide > sodium hypochlorite. For all biocides, greater antimicrobial reductions were seen when treating stainless steel and fabric than when treating plastic-associated microorganisms. The experimental fogging system and assay protocol designed within this study were shown capable of differentiating the comparative efficacies of multiple chlorine-matched biocidal aerosols against a spectrum of target organisms on a range of test surface materials and would be appropriate for testing other biocidal aerosol treatments or material surfaces. PMID:23459480

  5. Effects of electroconvulsive therapy and desipramine on neuroendocrine responses to the clonidine challenge test.

    PubMed Central

    Coote, M; Wilkins, A; Werstiuk, E S; Steiner, M

    1998-01-01

    OBJECTIVE: To investigate responses to the clonidine challenge test in depression, and after electroconvulsive therapy (ECT) or desipramine treatment for depression, in order to determine the usefulness of noradrenergic responses to clonidine as a state or trait marker in depression. PATIENTS: Twenty-six patients with depression and 15 control subjects. SETTING: The psychiatric ward of St. Joseph's Hospital in Hamilton. INTERVENTIONS: In the patients with depression: clonidine challenge pre- and post-treatment with ECT or desipramine. In the controls: 2 clonidine challenge tests 4 to 8 weeks apart. OUTCOME MEASURES: The primary measure was the growth hormone response to the clonidine challenge. Plasma norepinephrine, 3-methoxy-4-hydroxyphenylglycol (MHPG), cortisol, blood pressure, pulse and sedation levels were examined in subgroups of participants as secondary measures. RESULTS: The pre-treatment growth hormone response to clonidine was significantly more blunted in patients than in controls (p = 0.02). This response improved in both treatment groups after therapy and, although it remained decreased, there was no longer a significant difference in response between the patients and the controls. In the patients, a decreased growth hormone response to clonidine at baseline was correlated with response to treatment. Of the secondary measures, patient baseline norepinephrine levels were significantly elevated pre- and post-treatment, although there were no significant group-by-time challenge effects. MHPG levels were not significantly different pre- and post-treatment between patients and controls. Baseline blood pressure and pulse were elevated in the patients pre- and post-treatment. These differences were not statistically significant and did not change after treatment. Sedation levels were not significantly different among the groups at baseline. Clonidine-induced sedation occurred significantly earlier in the patients pretreatment and improved to the range of

  6. Technical Challenges for a Comprehensive Test Ban: A historical perspective to frame the future (Invited)

    NASA Astrophysics Data System (ADS)

    Wallace, T. C.

    2013-12-01

    In the summer of 1958 scientists from the Soviet block and the US allies met in Geneva to discuss what it would take to monitor a forerunner to a Comprehensive Test Ban Treaty at the 'Conference of Experts to Study the Possibility of Detecting Violations of a Possible Agreement on Suspension of Nuclear Tests'. Although armed with a limited resume of observations, the conference recommended a multi-phenomenology approach (air sampling, acoustics, seismic and electromagnetic) deployed it a network of 170 sites scattered across the Northern Hemisphere, and hypothesized a detection threshold of 1kt for atmospheric tests and 5kt for underground explosions. The conference recommendations spurred vigorous debate, with strong disagreement with the stated detection hypothesis. Nevertheless, the technical challenges posed lead to a very focused effort to improve facilities, methodologies and, most importantly, research and development on event detection, location and identification. In the ensuing 50 years the various challenges arose and were eventually 'solved'; these included quantifying yield determination to enter a Limited Threshold Test Ban, monitoring broad areas of emerging nuclear nations, and after the mid-1990s lowering the global detection threshold to sub-kiloton levels for underground tests. Today there is both an international monitoring regime (ie, the International Monitoring System, or IMS) and a group of countries that have their own national technical means (NTM). The challenges for the international regime are evolving; the IMS has established itself as a very credible monitoring system, but the demand of a CTBT to detect and identify a 'nuclear test' of diminished size (zero yield) poses new technical hurdles. These include signal processing and understanding limits of resolution, location accuracy, integration of heterogeneous data, and accurately characterizing anomalous events. It is possible to extrapolate past technical advances to predict what

  7. Radiation Testing, Characterization and Qualification Challenges for Modern Microelectronics and Photonics Devices and Technologies

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.; Cohn, Lewis M.

    2008-01-01

    At GOMAC 2007, we discussed a selection of the challenges for radiation testing of modern semiconductor devices focusing on state-of-the-art memory technologies. This included FLASH non-volatile memories (NVMs) and synchronous dynamic random access memories (SDRAMs). In this presentation, we extend this discussion in device packaging and complexity as well as single event upset (SEU) mechanisms using several technology areas as examples including: system-on-a-chip (SOC) devices and photonic or fiber optic systems. The underlying goal is intended to provoke thought for understanding the limitations and interpretation of radiation testing results.

  8. Evaluating stress as a challenge is associated with superior attentional control and motor skill performance: testing the predictions of the biopsychosocial model of challenge and threat.

    PubMed

    Vine, Samuel J; Freeman, Paul; Moore, Lee J; Chandra-Ramanan, Roy; Wilson, Mark R

    2013-09-01

    The biopsychosocial model of challenge and threat (Blascovich, 2008) suggests that individuals who evaluate a performance situation as a challenge will perform better than those who evaluate it as a threat. However, limited research has examined (a) the influence of challenge and threat evaluations on learned motor performance under pressure and (b) the attentional processes by which this effect occurs. In the present study 52 novices performed a motor task (laparoscopic surgery), for which optimal visual attentional control has been established. Participants performed a Baseline trial (when the task was novel) and were then trained to proficiency before performing under pressurized conditions designed to increase anxiety (Pressure). At Baseline, regression analyses were performed to examine the relationship between challenge/threat evaluations and the outcome variables (performance, cardiovascular response, and visual attention). At Pressure, hierarchical regression analyses (controlling for the degree of learning) were performed to examine the relationship between challenge/threat evaluations and the outcome variables. At both Baseline and Pressure tests evaluating the task as more of a challenge was associated with more effective attentional control and superior performance. In the Baseline test, evaluating the task as more of a challenge was associated with differential cardiovascular responses. Although there is some support for an attentional explanation of differential performance effects, additional analyses did not reveal mediators of the relationship between challenge/threat evaluations and motor performance. The findings have implications for the training and performance of motor skills in pressurized environments (e.g., surgery, sport, aviation).

  9. Use of In Situ Cloud Condensation Nuclei, Extinction, and Aerosol Size Distribution Measurements to Test a Method for Retrieving Cloud Condensation Nuclei Profiles From Surface Measurements

    NASA Technical Reports Server (NTRS)

    Ghan, Stephen J.; Rissman, Tracey A.; Ellman, Robert; Ferrare, Richard A.; Turner, David; Flynn, Connor; Wang, Jian; Ogren, John; Hudson, James; Jonsson, Haflidi H.; VanReken, Timothy; Flagan, Richard C.; Seinfeld, John H.

    2006-01-01

    If the aerosol composition and size distribution below cloud are uniform, the vertical profile of cloud condensation nuclei (CCN) concentration can be retrieved entirely from surface measurements of CCN concentration and particle humidification function and surface-based retrievals of relative humidity and aerosol extinction or backscatter. This provides the potential for long-term measurements of CCN concentrations near cloud base. We have used a combination of aircraft, surface in situ, and surface remote sensing measurements to test various aspects of the retrieval scheme. Our analysis leads us to the following conclusions. The retrieval works better for supersaturations of 0.1% than for 1% because CCN concentrations at 0.1% are controlled by the same particles that control extinction and backscatter. If in situ measurements of extinction are used, the retrieval explains a majority of the CCN variance at high supersaturation for at least two and perhaps five of the eight flights examined. The retrieval of the vertical profile of the humidification factor is not the major limitation of the CCN retrieval scheme. Vertical structure in the aerosol size distribution and composition is the dominant source of error in the CCN retrieval, but this vertical structure is difficult to measure from remote sensing at visible wavelengths.

  10. Ares I-X Flight Test Development Challenges and Success Factors

    NASA Technical Reports Server (NTRS)

    Askins, Bruce; Davis, Steve; Olsen, Ronald; Taylor, James

    2010-01-01

    The NASA Constellation Program's Ares I-X rocket launched successfully on October 28, 2009 collecting valuable data and providing risk reduction for the Ares I project. The Ares I-X mission was formulated and implemented in less than four years commencing with the Exploration Systems Architecture Study in 2005. The test configuration was founded upon assets and processes from other rocket programs including Space Shuttle, Atlas, and Peacekeeper. For example, the test vehicle's propulsion element was a Shuttle Solid Rocket Motor. The Ares I-X rocket comprised a motor assembly, mass and outer mold line simulators of the Ares I Upper Stage, Orion Spacecraft and Launch Abort System, a roll control system, avionics, and other miscellaneous components. The vehicle was 327 feet tall and weighed approximately 1,800,000 pounds. During flight the rocket reached a maximum speed of Mach 4.8 and an altitude of 150,000 feet. The vehicle demonstrated staging at 130,000 feet, tested parachutes for recovery of the motor, and utilized approximately 900 sensors for data collection. Developing a new launch system and preparing for a safe flight presented many challenges. Specific challenges included designing a system to withstand the environments, manufacturing large structures, and re-qualifying heritage hardware. These and other challenges, if not mitigated, may have resulted in test cancellation. Ares I-X succeeded because the mission was founded on carefully derived objectives, led by decisive and flexible management, implemented by an exceptionally talented and dedicated workforce, and supported by a thorough independent review team. Other major success factors include the use of proven heritage hardware, a robust System Integration Laboratory, multi-NASA center and contractor team, concurrent operations, efficient vehicle assembly, effective risk management, and decentralized element development with a centralized control board. Ares I-X was a technically complex test that

  11. Evaluations of Thin Cirrus Contamination and Screening in Ground Aerosol Observations Using Collocated Lidar Systems

    NASA Technical Reports Server (NTRS)

    Huang, Jingfeng; Hsu, N. Christina; Tsay, Si-Chee; Holben, Brent N.; Welton, Ellsworth J.; Smirnov, Alexander; Jeong, Myeong-Jae; Hansell, Richard A.; Berkoff, Timothy A.

    2012-01-01

    Cirrus clouds, particularly sub visual high thin cirrus with low optical thickness, are difficult to be screened in operational aerosol retrieval algorithms. Collocated aerosol and cirrus observations from ground measurements, such as the Aerosol Robotic Network (AERONET) and the Micro-Pulse Lidar Network (MPLNET), provide us with an unprecedented opportunity to examine the susceptibility of operational aerosol products to thin cirrus contamination. Quality assured aerosol optical thickness (AOT) measurements were also tested against the CALIPSO vertical feature mask (VFM) and the MODIS-derived thin cirrus screening parameters for the purpose of evaluating thin cirrus contamination. Key results of this study include: (1) Quantitative evaluations of data uncertainties in AERONET AOT retrievals are conducted. Although AERONET cirrus screening schemes are successful in removing most cirrus contamination, strong residuals displaying strong spatial and seasonal variability still exist, particularly over thin cirrus prevalent regions during cirrus peak seasons, (2) Challenges in matching up different data for analysis are highlighted and corresponding solutions proposed, and (3) Estimation of the relative contributions from cirrus contamination to aerosol retrievals are discussed. The results are valuable for better understanding and further improving ground aerosol measurements that are critical for aerosol-related climate research.

  12. Testing of an automated online EA-IRMS method for fast and simultaneous carbon content and stable isotope measurement of aerosol samples

    NASA Astrophysics Data System (ADS)

    Major, István; Gyökös, Brigitta; Túri, Marianna; Futó, István; Filep, Ágnes; Hoffer, András; Molnár, Mihály

    2016-04-01

    Comprehensive atmospheric studies have demonstrated that carbonaceous aerosol is one of the main components of atmospheric particulate matter over Europe. Various methods, considering optical or thermal properties, have been developed for quantification of the accurate amount of both organic and elemental carbon constituents of atmospheric aerosol. The aim of our work was to develop an alternative fast and easy method for determination of the total carbon content of individual aerosol samples collected on prebaked quartz filters whereby the mass and surface concentration becomes simply computable. We applied the conventional "elemental analyzer (EA) coupled online with an isotope ratio mass spectrometer (IRMS)" technique which is ubiquitously used in mass spectrometry. Using this technique we are able to measure simultaneously the carbon stable isotope ratio of the samples, as well. During the developing process, we compared the EA-IRMS technique with an off-line catalytic combustion method worked out previously at Hertelendi Laboratory of Environmental Studies (HEKAL). We tested the combined online total carbon content and stable isotope ratio measurement both on standard materials and real aerosol samples. Regarding the test results the novel method assures, on the one hand, at least 95% of carbon recovery yield in a broad total carbon mass range (between 100 and 3000 ug) and, on the other hand, a good reproducibility of stable isotope measurements with an uncertainty of ± 0.2 per mill. Comparing the total carbon results obtained by the EA-IRMS and the off-line catalytic combustion method we found a very good correlation (R2=0.94) that proves the applicability of both preparation method. Advantages of the novel method are the fast and simplified sample preparation steps and the fully automated, simultaneous carbon stable isotope ratio measurement processes. Furthermore stable isotope ratio results can effectively be applied in the source apportionment

  13. International Cooperative for Aerosol Prediction Workshop on Aerosol Forecast Verification

    NASA Technical Reports Server (NTRS)

    Benedetti, Angela; Reid, Jeffrey S.; Colarco, Peter R.

    2011-01-01

    The purpose of this workshop was to reinforce the working partnership between centers who are actively involved in global aerosol forecasting, and to discuss issues related to forecast verification. Participants included representatives from operational centers with global aerosol forecasting requirements, a panel of experts on Numerical Weather Prediction and Air Quality forecast verification, data providers, and several observers from the research community. The presentations centered on a review of current NWP and AQ practices with subsequent discussion focused on the challenges in defining appropriate verification measures for the next generation of aerosol forecast systems.

  14. Final Report: Part 1. In-Place Filter Testing Instrument for Nuclear Material Containers. Part 2. Canister Filter Test Standards for Aerosol Capture Rates.

    SciTech Connect

    Brown, Austin Douglas; Runnels, Joel T.; Moore, Murray E.; Reeves, Kirk Patrick

    2014-11-02

    A portable instrument has been developed to assess the functionality of filter sand o-rings on nuclear material storage canisters, without requiring removal of the canister lid. Additionally, a set of fifteen filter standards were procured for verifying aerosol leakage and pressure drop measurements in the Los Alamos Filter Test System. The US Department of Energy uses several thousand canisters for storing nuclear material in different chemical and physical forms. Specialized filters are installed into canister lids to allow gases to escape, and to maintain an internal ambient pressure while containing radioactive contaminants. Diagnosing the condition of container filters and canister integrity is important to ensure worker and public safety and for determining the handling requirements of legacy apparatus. This report describes the In-Place-Filter-Tester, the Instrument Development Plan and the Instrument Operating Method that were developed at the Los Alamos National Laboratory to determine the “as found” condition of unopened storage canisters. The Instrument Operating Method provides instructions for future evaluations of as-found canisters packaged with nuclear material. Customized stainless steel canister interfaces were developed for pressure-port access and to apply a suction clamping force for the interface. These are compatible with selected Hagan-style and SAVY-4000 storage canisters that were purchased from NFT (Nuclear Filter Technology, Golden, CO). Two instruments were developed for this effort: an initial Los Alamos POC (Proof-of-Concept) unit and the final Los Alamos IPFT system. The Los Alamos POC was used to create the Instrument Development Plan: (1) to determine the air flow and pressure characteristics associated with canister filter clogging, and (2) to test simulated configurations that mimicked canister leakage paths. The canister leakage scenarios included quantifying: (A) air leakage due to foreign material (i.e. dust and hair

  15. Development of a bacterial challenge test for gnotobiotic Nile tilapia Oreochromis niloticus larvae.

    PubMed

    Situmorang, Magdalena Lenny; Dierckens, Kristof; Mlingi, Frank Thomas; Van Delsen, Bart; Bossier, Peter

    2014-04-23

    Gastrointestinal microbiota have an important impact on fish health and disease, stimulating interest in a better understanding of how these gastrointestinal microbial communities are composed and consequently affect host fitness. In this respect, probiotic microorganisms have been extensively used in recent aquaculture production. To study the use of probiotics in the treatment of infectious diseases, the establishment of a method of experimental infection to obtain consistent results for mortality and infection in challenge tests is important. In pathogen-screening tests, 4 candidate pathogenic bacteria strains (Edwardsiella ictaluri gly09, E. ictaluri gly10, E. tarda LMG2793 and Streptococcus agalactiae LMG15977) were individually tested on xenic Nile tilapia larvae. Only Edwardsiella strains delivered via Artemia nauplii, with or without additional pathogen delivery via the culture water, led to increased mortality in fish larvae. A gnotobiotic Nile tilapia larvae model system was developed to provide a research tool to investigate the effects and modes-of-action of probiotics under controlled conditions. A double disinfection procedure using hydrogen peroxide and sodium hypochlorite solution was applied to the fish eggs, which were subsequently incubated in a cocktail of antibiotic and antifungal agents. In the gnotobiotic challenge test, E. ictaluri gly09R was added to the model system via Artemia nauplii and culture water, resulting in a significant mortality of the gnotobiotic fish larvae. The developed gnotobiotic Nile tilapia model can be used as a tool to extend understanding of the mechanisms involved in host-microbe interactions and to evaluate new methods of disease control.

  16. Outpatient penicillin use after negative skin testing and drug challenge in a pediatric population.

    PubMed

    Picard, Matthieu; Paradis, Louis; Nguyen, Mélanie; Bégin, Philippe; Paradis, Jean; Des Roches, Anne

    2012-01-01

    The practice of elective penicillin skin testing could be compromised by the fact that patients, their parents, or their physicians remain reluctant to reuse penicillin-class antibiotics (PCAs) despite a negative evaluation by an allergist. This study addresses reuse of PCAs in a pediatric population after negative penicillin skin testing and drug challenge and factors associated with its reluctance. All children evaluated for a history of penicillin allergy at the CHU Sainte-Justine Allergy Clinic between January 1998 and June 2000 with negative skin testing and drug challenge were included in the study. A telephone survey was conducted between May and October 2002 to assess the perception of the initial reaction by the parents, subsequent use of antibiotics, and antibiotic-related adverse reactions. Among the 200 children selected, parents of 170 (85%) children completed the survey. Since the allergist evaluation, 130 (76%) children had received antibiotics. PCA was used in 59 (45%) children. Parents of 24 (18%) children refused PCAs because they still feared an adverse reaction. They were more likely to have been very frightened by their child's allergic reaction than other parents whose children had used PCAs (p = 0.008). Although elective penicillin skin testing is useful and safe in the pediatric population, a significant proportion of parents still refuse PCAs even though they are needed. Identification of parents that were very frightened by their children's allergic reactions and additional reassurance could improve this situation.

  17. Development of a BCG challenge model for the testing of vaccine candidates against tuberculosis in cattle.

    PubMed

    Villarreal-Ramos, Bernardo; Berg, Stefan; Chamberlain, Laura; McShane, Helen; Hewinson, R Glyn; Clifford, Derek; Vordermeier, Martin

    2014-09-29

    Vaccination is being considered as part of a sustainable strategy for the control of bovine tuberculosis (BTB) in the UK. The live attenuated Mycobacterium bovis bacillus Calmette-Guerin (BCG) has been used experimentally to vaccinate cattle against BTB. However, BCG confers partial protection against BTB and therefore, there is a need to develop improved vaccines. BTB vaccine efficacy experiments require the use of biosafety level 3 facilities which are expensive to maintain, generally oversubscribed and represent a bottle neck for the testing of vaccine candidates. One indicator of the induction of protective responses would be the ability of the host's immune response to control/kill mycobacteria. In this work we have evaluated an intranodal BCG challenge for the selection of vaccine candidates at biosafety level 2 which are capable of inducing mycobactericidal responses. To our knowledge, this is the first such report. Whilst BCG only confers partial protection, it is still the standard against which other vaccines are judged. Therefore we tested the BCG intranodal challenge in BCG (Danish strain) vaccinated cattle and showed that vaccinated cattle had lower BCG cfu counts than naïve cattle at 14 and 21 days after intranodal challenge with BCG (Tokyo strain). This model could help prioritize competing TB vaccine candidates and exploration of primary and secondary immune responses to mycobacteria.

  18. Design Challenges Encountered in a Propulsion-Controlled Aircraft Flight Test Program

    NASA Technical Reports Server (NTRS)

    Maine, Trindel; Burken, John; Burcham, Frank; Schaefer, Peter

    1994-01-01

    The NASA Dryden Flight Research Center conducted flight tests of a propulsion-controlled aircraft system on an F-15 airplane. This system was designed to explore the feasibility of providing safe emergency landing capability using only the engines to provide flight control in the event of a catastrophic loss of conventional flight controls. Control laws were designed to control the flightpath and bank angle using only commands to the throttles. Although the program was highly successful, this paper highlights some of the challenges associated with using engine thrust as a control effector. These challenges include slow engine response time, poorly modeled nonlinear engine dynamics, unmodeled inlet-airframe interactions, and difficulties with ground effect and gust rejection. Flight and simulation data illustrate these difficulties.

  19. Adaptive identification and interpretation of pressure transient tests of horizontal wells: challenges and perspectives

    NASA Astrophysics Data System (ADS)

    Sergeev, V. L.; Van Hoang, Dong

    2016-09-01

    The paper deals with a topical issue of defining oil reservoir properties during transient tests of horizontal wells equipped with information-measuring systems and reducing well downtime. The aim is to consider challenges and perspectives of developing models and algorithms for adaptive identification and interpretation of transient tests in horizontal wells with pressure buildup curve analysis. The models and algorithms should allow analyzing flow behavior, defining oil reservoir properties and determining well test completion time, as well as reducing well downtime. The present paper is based on the previous theoretical and practical findings in the spheres of transient well testing, systems analysis, system identification, function optimization and linear algebra. Field data and results of transient well tests with pressure buildup curve analysis have also been considered. The suggested models and algorithms for adaptive interpretation of transient tests conducted in horizontal wells with resulting pressure buildup curve make it possible to analyze flow behavior, as well as define the reservoir properties and determine well test completion time. The algorithms for adaptive interpretation are based on the integrated system of radial flow PBC models with time- dependent variables, account of additional a priori information and estimates of radial flow permeability. Optimization problems are solved with the case study of PBC interpretation for five horizontal wells of the Verkhnechonsk field.

  20. Diagnosis of food allergies: the impact of oral food challenge testing.

    PubMed

    Ito, Komei

    2013-01-01

    A diagnosis of food allergies should be made based on the observation of allergic symptoms following the intake of suspected foods and the presence of allergen-specific IgE antibodies. The oral food challenge (OFC) test is the most reliable clinical procedure for diagnosing food allergies. Specific IgE testing of allergen components as well as classical crude allergen extracts helps to make a more specific diagnosis of food allergies. The Japanese Society of Pediatric Allergy and Clinical Immunology issued the 'Japanese Pediatric Guideline for Food Allergy 2012' to provide information regarding the standardized diagnosis and management of food allergies. This review summarizes recent progress in the diagnosis of food allergies, focusing on the use of specific IgE tests and the OFC procedure in accordance with the Japanese guidelines.

  1. Design of challenge testing experiments to assess the variability of Listeria monocytogenes growth in foods.

    PubMed

    Augustin, Jean-Christophe; Bergis, Hélène; Midelet-Bourdin, Graziella; Cornu, Marie; Couvert, Olivier; Denis, Catherine; Huchet, Véronique; Lemonnier, Sabrina; Pinon, Anthony; Vialette, Michèle; Zuliani, Véronique; Stahl, Valérie

    2011-06-01

    The assessment of the evolution of micro-organisms naturally contaminating food must take into account the variability of biological factors, food characteristics and storage conditions. A research project involving eight French laboratories was conducted to quantify the variability of growth parameters of Listeria monocytogenes obtained by challenge testing in five food products. The residual variability corresponded to a coefficient of variation (CV) of approximately 20% for the growth rate (μ(max)) and 130% for the parameter K = μ(max) × lag. The between-batch and between-manufacturer variability of μ(max) was very dependent on the food tested and mean CV of approximately 20 and 35% were observed for these two sources of variability, respectively. The initial physiological state variability led to a CV of 100% for the parameter K. It appeared that repeating a limited number of three challenge tests with three different batches (or manufacturers) and with different initial physiological states seems often necessary and adequate to accurately assess the variability of the behavior of L. monocytogenes in a specific food produced by a given manufacturer (or for a more general food designation).

  2. Swatch Test Results of Phase 2 Commercial Chemical Protective Gloves to Challenge by Chemical Warfare Agents: Summary Report

    DTIC Science & Technology

    2001-01-01

    TEST RESULTS OF PHASE 2 COMMERCIAL CHEMICAL PROTECTIVE GLOVES TO CHALLENGE BY CHEMICAL WARFARE AGENTS : SUMMARY REPORT Robert S...Swatch testing Permeation testing GB Chemical protective gloves 15. NUMBER OF PAGES 53 16. PRICE CODE 17... warfare (CW) agent environment. Swatches of material from each glove design were tested for resistance to

  3. [Trends and Challenges of the Statutory Regulation of Molecular Genetic Tests].

    PubMed

    Nobori, Tsutomu

    2015-07-01

    Advances in basic science have made it possible to characterize tumors at molecular levels and exploit the differences in the genetic makeup of tumors for personalized cancer treatment. Biomarker tests are essential to stratify patients with the same tumor histology for appropriate treatment. Such tests are developed together with drugs, involving mainly molecular genetic tests at present, and are called companion diagnostics (CDx). Under the universal health care system in Japan, molecular genetic tests are permitted in clinics, and the fees are reimbursed only when approved diagnostic reagents or kits are used. However, new tests are developed so fast that the regulation cannot keep up with the pace. To fill this gap, the framework of advanced medical technologies was introduced in 1984. In 2012, this framework was amended to classify medical technology using unapproved diagnostics or home-brew assays as advanced medical technologies A. In my talk at this symposium, trends and challenges of the statutory regulation of molecular genetic tests in Japan were discussed, followed by personal proposals to advance the clinical application of novel medical technologies in the field of personalized cancer treatment.

  4. Gaia challenging performances verification: combination of spacecraft models and test results

    NASA Astrophysics Data System (ADS)

    Ecale, Eric; Faye, Frédéric; Chassat, François

    2016-08-01

    To achieve the ambitious scientific objectives of the Gaia mission, extremely stringent performance requirements have been given to the spacecraft contractor (Airbus Defence and Space). For a set of those key-performance requirements (e.g. end-of-mission parallax, maximum detectable magnitude, maximum sky density or attitude control system stability), this paper describes how they are engineered during the whole spacecraft development process, with a focus on the end-to-end performance verification. As far as possible, performances are usually verified by end-to-end tests onground (i.e. before launch). However, the challenging Gaia requirements are not verifiable by such a strategy, principally because no test facility exists to reproduce the expected flight conditions. The Gaia performance verification strategy is therefore based on a mix between analyses (based on spacecraft models) and tests (used to directly feed the models or to correlate them). Emphasis is placed on how to maximize the test contribution to performance verification while keeping the test feasible within an affordable effort. In particular, the paper highlights the contribution of the Gaia Payload Module Thermal Vacuum test to the performance verification before launch. Eventually, an overview of the in-flight payload calibration and in-flight performance verification is provided.

  5. [Expansion of HIV counseling and testing strategies: technical challenges and ethical-political tensions].

    PubMed

    Mora Cárdenas, Claudia Mercedes; Monteiro, Simone; Moreira, Carlos Otávio Fiúza

    2014-08-01

    Incentives to provide universal access to antiretroviral therapy in order to control the HIV/AIDS epidemic also encouraged the diversification of HIV testing strategies, as demonstrated by the simultaneous existence of Voluntary Counseling and Testing (VCT) and Provider-Initiated HIV Testing and Counseling (PITC). This paper analyzes the concepts, principles and implementation of the VCT and PITC models regarding counseling, confidentiality and informed consent in Brazil and other countries, based on a literature review of works in the Lilacs, Medline, Sociological Abstracts and Cochrane databases published between 2000 and 2013. According to the literature, PITC increases rates of testing in comparison with VCT, but reduces sexual and reproductive rights and the autonomy of users. These findings suggest technical challenges and ethical tensions between the paradigm of exceptionalism and the normalization of HIV testing. The necessity to reconcile increased access to HIV tests with the local capacity to offer comprehensive care for people living with HIV/AIDS is highlighted. It is recommended that interdisciplinary studies about the social effects of VCT and PITC be amplified.

  6. Safety Testing of Dengue-1 and Dengue-3 Seeds for Human Challenges, Unattenuated.

    DTIC Science & Technology

    1987-10-26

    Maryland 21701-5012 ELEMENT NO. NO. 3M1- NO0. CESSION NO. 11. TITLE (Inciude Security Clanafication) 627A 127A80I C E 09 (U) Safety Testing of Dengue -1...and Dengue -3 Seeds for Human Challenges, Unattenuated 12. PERSONAL AUrWOR(S) Potash, Loui.s 13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT...of necessary and identify by block number) FIELD GROUP SUB-GROUP 06 13 ngue-M- Dengue -3; Hepatitis A; Viral seeds; Vaccine no;’-- 03 I 19. ABSTRACI’ 4

  7. Behaviour of Listeria Monocytogenes in Artisanal Raw Milk Pecorino Umbro Cheese: A Microbiological Challenge Test

    PubMed Central

    Ortenzi, Roberta; Branciari, Raffaella; Primavilla, Sara; Valiani, Andrea

    2015-01-01

    In the present study, a microbiological challenge test in artificially contaminated raw milk Pecorino Umbro cheese during cheese-making was carried out. Raw ewe milk was contaminated by a suspension of particular Listeria monocytogenes strains. The number of L. monocytogenes and L. monocytogenes dynamic growth were evaluated during cheese-making and storage. A significant decrease of the viable count of L. monocytogenes was observed during ripening and L. monocytogenes viable count was below the limit of quantification during storage. The results show that the product is unable to support the growth of the pathogen. PMID:27800412

  8. Systematic review of acute levodopa and apomorphine challenge tests in the diagnosis of idiopathic Parkinson's disease

    PubMed Central

    Clarke, C; Davies, P

    2000-01-01

    OBJECTIVES—To perform a systematic review of studies examining the diagnostic accuracy of acute challenge tests with levodopa and/or apomorphine in parkinsonian syndromes to assess their value in the diagnosis of idiopathic Parkinson's disease.
METHODS—A literature search including Medline and the Cochrane Library was performed for studies published in any language comparing acute levodopa and/or apomorphine response with chronic levodopa therapy in parkinsonian syndromes. Abstracted sensitivity and specificity data were summarised using variance weighting and conditional logistic regression for studies comparing two challenge tests.
RESULTS—Thirteen studies were located: four examining de novo patients and nine examining patients with well established idiopathic Parkinson's disease and non-parkinsonian conditions. Despite the significant heterogeneity in the methodologies employed, the comparable results suggest that this had little effect on the accuracy of the tests. The sensitivity for the diagnosis of established idiopathic Parkinson's disease was: apomorphine 0.86 (95% confidence interval (95% CI) 0.78-0.94), acute levodopa 0.75 (95% CI 0.64-0.85), and chronic levodopa therapy 0.91 (95% CI 0.85-0.99). The specificity for the diagnosis of established idiopathic Parkinson's disease was: apomorphine 0.85 (95% CI 0.74-0.96), acute levodopa 0.87(95% CI 0.77-0.97), and chronic levodopa therapy 0.77 (95% CI 0.61-0.93). The number of patients positive for each test divided by the number with clinically diagnosed de novo disease was: apomorphine 0.63 (95% CI 0.56-0.70), acute levodopa 0.69 (95% CI 0.59-0.80), and chronic levodopa therapy 0.76 (95% CI 0.70-0.82).
CONCLUSIONS—The accuracy of the acute levodopa and apomorphine challenge tests is similar to, but not superior than, that of chronic levodopa therapy in the diagnosis of idiopathic Parkinson's disease. As most patients will be given chronic dopamimetic therapy, these tests add nothing while

  9. Spatio-temporal variability of aerosols in the tropics relationship with atmospheric and oceanic environments

    NASA Astrophysics Data System (ADS)

    Zuluaga-Arias, Manuel D.

    2011-12-01

    Earth's radiation budget is directly influenced by aerosols through the absorption of solar radiation and subsequent heating of the atmosphere. Aerosols modulate the hydrological cycle indirectly by modifying cloud properties, precipitation and ocean heat storage. In addition, polluting aerosols impose health risks in local, regional and global scales. In spite of recent advances in the study of aerosols variability, uncertainty in their spatio-temporal distributions still presents a challenge in the understanding of climate variability. For example, aerosol loading varies not only from year to year but also on higher frequency intraseasonal time scales producing strong variability on local and regional scales. An assessment of the impact of aerosol variability requires long period measurements of aerosols at both regional and global scales. The present dissertation compiles a large database of remotely sensed aerosol loading in order to analyze its spatio-temporal variability, and how this load interacts with different variables that characterize the dynamic and thermodynamic states of the environment. Aerosol Index (AI) and Aerosol Optical Depth (AOD) were used as measures of the atmospheric aerosol load. In addition, atmospheric and oceanic satellite observations, and reanalysis datasets is used in the analysis to investigate aerosol-environment interactions. A diagnostic study is conducted to produce global and regional aerosol satellite climatologies, and to analyze and compare the validity of aerosol retrievals. We find similarities and differences between the aerosol distributions over various regions of the globe when comparing the different satellite retrievals. A nonparametric approach is also used to examine the spatial distribution of the recent trends in aerosol concentration. A significant positive trend was found over the Middle East, Arabian Sea and South Asian regions strongly influenced by increases in dust events. Spectral and composite analyses

  10. Challenging the Accuracy of a Single-test Lactate Threshold Protocol in Collegiate Rowers

    PubMed Central

    SOMA, ERICA A.; LOCKARD, MICHAEL M.; STAVRIANEAS, STASINOS

    2010-01-01

    Elite rowers use lactate threshold (LT) estimates as a basis for training intensity in order to achieve the greatest training volume. For convenience, LT is usually determined in a maximal LT/VO2max test. This simultaneous test is problematic because it requires a large power increment, which may not give the most accurate LT. PURPOSE To challenge the validity of a simultaneous LT/VO2max test to estimate LT in rowers. METHODS Collegiate rowers (n=20, 16F and 4M, age 19.3±1.3 years, height 171.5±7.1 cm, weight 70±14 kg, VO2max 44.6±5.5 ml•kg−1•min−1) performed two LT tests. Participants completed an incremental VO2max test with 3-minute intervals increasing by 30W and 40W for women and men respectively. The second test consisted of five 6-minute stages of 10W increments starting from 20W below the estimated LT. For both tests, blood lactate was measured at the end of each stage and LT was determined by the lactate deflection point. The difference in intensity between the first deflection point and the LT was then calculated. RESULTS Average difference between LT1 and LT2 was 1.15 ± 13.4W, and were not statistically different (p=0.204). Average absolute difference was 9.95 ± 8.80W, and was different from the average (p=0.022). CONCLUSION A second incremental test should be performed for the most precise determination of LT. This is particularly important to rowers who rely on LT to determine training intensities. PMID:27182349

  11. Feasibility of HIV point-of-care tests for resource-limited settings: challenges and solutions.

    PubMed

    Stevens, Wendy; Gous, Natasha; Ford, Nathan; Scott, Lesley E

    2014-09-08

    Improved access to anti-retroviral therapy increases the need for affordable monitoring using assays such as CD4 and/or viral load in resource-limited settings. Barriers to accessing treatment, high rates of loss to initiation and poor retention in care are prompting the need to find alternatives to conventional centralized laboratory testing in certain countries. Strong advocacy has led to a rapidly expanding repertoire of point-of-care tests for HIV. point-of-care testing is not without its challenges: poor regulatory control, lack of guidelines, absence of quality monitoring and lack of industry standards for connectivity, to name a few. The management of HIV increasingly requires a multidisciplinary testing approach involving hematology, chemistry, and tests associated with the management of non-communicable diseases, thus added expertise is needed. This is further complicated by additional human resource requirements and the need for continuous training, a sustainable supply chain, and reimbursement strategies. It is clear that to ensure appropriate national implementation either in a tiered laboratory model or a total decentralized model, clear country-specific assessments need to be conducted.

  12. ENCAPSULATED AEROSOLS

    DTIC Science & Technology

    acetate, polymerized rapidly and produced some polymer film encapsulation of the aerosol droplets. A two-stage microcapsule generator was designed...encapsulating material, the generator also produced microcapsules of dibutyl phosphite in polyethylene, nitrocellulose, and natural rubber.

  13. Summary of longitudinal stability and control parameters as determined from Space Shuttle Challenger flight test data

    NASA Technical Reports Server (NTRS)

    Suit, William T.

    1989-01-01

    Estimates of longitudinal stability and control parameters for the space shuttle were determined by applying a maximum likelihood parameter estimation technique to Challenger flight test data. The parameters for pitching moment coefficient, C(m sub alpha), (at different angles of attack), pitching moment coefficient, C(m sub delta e), (at different elevator deflections) and the normal force coefficient, C(z sub alpha), (at different angles of attack) describe 90 percent of the response to longitudinal inputs during Space Shuttle Challenger flights with C(m sub delta e) being the dominant parameter. The values of C(z sub alpha) were found to be input dependent for these tests. However, when C(z sub alpha) was set at preflight predictions, the values determined for C(m sub delta e) changed less than 10 percent from the values obtained when C(z sub alpha) was estimated as well. The preflight predictions for C(z sub alpha) and C(m sub alpha) are acceptable values, while the values of C(z sub delta e) should be about 30 percent less negative than the preflight predictions near Mach 1, and 10 percent less negative, otherwise.

  14. Chemical and Biological Defense Test and Evaluation (T&E) Future Challenges

    DTIC Science & Technology

    2012-07-01

    the appropriate phase (e.g., vapor, droplet , particulates); and (3) overcoming problems of simulants accurately representing systems performance. Many...sensors for manikins, detection of NTA droplets , and aerosol sensors. As devices become smaller, sample handling and preparation become of paramount...a) Technologies: Photoionization; lab on a chip ( microfluidics , electrokinetics); functionalized microcantilevers; quantum dots (gene and aptimer

  15. AGONIST-MEDIATED AIRWAY CHALLENGE: CARDIOPULMONARY INTERACTIONS MODULATE GAS EXCHANGE AND RECOVERY

    EPA Science Inventory

    ABSTRACT
    To better understand the early phase response (0-60 minutes) to airway challenge, we examined cardiopulmonary reactions during ovalbumin (OVA), histamine, and methacholine aerosol challenge tests in guinea pigs. Propranolol and 100% O2 were used to modify the reacti...

  16. Non-invasive prenatal testing: a review of international implementation and challenges

    PubMed Central

    Allyse, Megan; Minear, Mollie A; Berson, Elisa; Sridhar, Shilpa; Rote, Margaret; Hung, Anthony; Chandrasekharan, Subhashini

    2015-01-01

    Noninvasive prenatal genetic testing (NIPT) is an advance in the detection of fetal chromosomal aneuploidies that analyzes cell-free fetal DNA in the blood of a pregnant woman. Since its introduction to clinical practice in Hong Kong in 2011, NIPT has quickly spread across the globe. While many professional societies currently recommend that NIPT be used as a screening method, not a diagnostic test, its high sensitivity (true positive rate) and specificity (true negative rate) make it an attractive alternative to the serum screens and invasive tests currently in use. Professional societies also recommend that NIPT be accompanied by genetic counseling so that families can make informed reproductive choices. If NIPT becomes more widely adopted, States will have to implement regulation and oversight to ensure it fits into existing legal frameworks, with particular attention to returning fetal sex information in areas where sex-based abortions are prevalent. Although there are additional challenges for NIPT uptake in the developing world, including the lack of health care professionals and infrastructure, the use of NIPT in low-resource settings could potentially reduce the need for skilled clinicians who perform invasive testing. Future advances in NIPT technology promise to expand the range of conditions that can be detected, including single gene disorders. With these advances come questions of how to handle incidental findings and variants of unknown significance. Moving forward, it is essential that all stakeholders have a voice in crafting policies to ensure the ethical and equitable use of NIPT across the world. PMID:25653560

  17. Mars Science Laboratory Sample Acquisition, Sample Processing and Handling: Subsystem Design and Test Challenges

    NASA Technical Reports Server (NTRS)

    Jandura, Louise

    2010-01-01

    The Sample Acquisition/Sample Processing and Handling subsystem for the Mars Science Laboratory is a highly-mechanized, Rover-based sampling system that acquires powdered rock and regolith samples from the Martian surface, sorts the samples into fine particles through sieving, and delivers small portions of the powder into two science instruments inside the Rover. SA/SPaH utilizes 17 actuated degrees-of-freedom to perform the functions needed to produce 5 sample pathways in support of the scientific investigation on Mars. Both hardware redundancy and functional redundancy are employed in configuring this sampling system so some functionality is retained even with the loss of a degree-of-freedom. Intentional dynamic environments are created to move sample while vibration isolators attenuate this environment at the sensitive instruments located near the dynamic sources. In addition to the typical flight hardware qualification test program, two additional types of testing are essential for this kind of sampling system: characterization of the intentionally-created dynamic environment and testing of the sample acquisition and processing hardware functions using Mars analog materials in a low pressure environment. The overall subsystem design and configuration are discussed along with some of the challenges, tradeoffs, and lessons learned in the areas of fault tolerance, intentional dynamic environments, and special testing

  18. Integrated Cognitive-neuroscience Architectures for Understanding Sensemaking (ICArUS): Phase 2 Challenge Problem Design and Test Specification

    DTIC Science & Technology

    2014-11-01

    Integrated Cognitive- neuroscience Architectures for Understanding Sensemaking (ICArUS): Phase 2 Challenge Problem Design and Test...SUBTITLE Integrated Cognitive- neuroscience Architectures for Understanding Sensemaking (ICArUS): A Computational Basis for ICArUS: Phase 2 Challenge...IARPA program ICArUS (Integrated Cognitive- neuroscience Architectures for Understanding Sensemaking) requires a research problem that poses cognitive

  19. United States Army Operational Test Command (USAOTC) Integrated Technologies Evolving to Meet New Challenges - A Study in Cross Command Collaboration

    DTIC Science & Technology

    2009-01-01

    Operations Rehearsal Model TBCC Threat Battle Command Capability TEC Topographic Engineering Center TENA Test and Training Enabling Architecture...1 Paper Title: United States Army Operational Test Command (USAOTC) Integrated Technologies Evolving to Meet New Challenges – A Study in Cross...and Integration Division John.Diem@us.army.mil USA Operational Test Command Transformation Technology Directorate ATTN: TEOT-TT 91012 Station

  20. Multiple roles of Myd88 in the immune response to the plague F1-V vaccine and in protection against an aerosol challenge of Yersinia pestis CO92 in mice.

    PubMed

    Dankmeyer, Jennifer L; Fast, Randy L; Cote, Christopher K; Worsham, Patricia L; Fritz, David; Fisher, Diana; Kern, Steven J; Merkel, Tod; Kirschning, Carsten J; Amemiya, Kei

    2014-01-01

    The current candidate vaccine against Yersinia pestis infection consists of two subunit proteins: the capsule protein or F1 protein and the low calcium response V protein or V-antigen. Little is known of the recognition of the vaccine by the host's innate immune system and how it affects the acquired immune response to the vaccine. Thus, we vaccinated Toll-like receptor (Tlr) 2, 4, and 2/4-double deficient, as well as signal adaptor protein Myd88-deficient mice. We found that Tlr4 and Myd88 appeared to be required for an optimal immune response to the F1-V vaccine but not Tlr2 when compared to wild-type mice. However, there was a difference between the requirement for Tlr4 and MyD88 in vaccinated animals. When F1-V vaccinated Tlr4 mutant (lipopolysaccharide tolerant) and Myd88-deficient mice were challenged by aerosol with Y. pestis CO92, all but one Tlr4 mutant mice survived the challenge, but no vaccinated Myd88-deficient mice survived the challenge. Spleens from these latter nonsurviving mice showed that Y. pestis was not cleared from the infected mice. Our results suggest that MyD88 appears to be important for both an optimal immune response to F1-V and in protection against a lethal challenge of Y. pestis CO92 in F1-V vaccinated mice.

  1. The Current Landscape of Genetic Testing in Cardiovascular Malformations: Opportunities and Challenges

    PubMed Central

    Landis, Benjamin J.; Ware, Stephanie M.

    2016-01-01

    Human cardiovascular malformations (CVMs) frequently have a genetic contribution. Through the application of novel technologies, such as next-generation sequencing, DNA sequence variants associated with CVMs are being identified at a rapid pace. While clinicians are now able to offer testing with NGS gene panels or whole exome sequencing to any patient with a CVM, the interpretation of genetic variation remains problematic. Variable phenotypic expression, reduced penetrance, inconsistent phenotyping methods, and the lack of high-throughput functional testing of variants contribute to these challenges. This article elaborates critical issues that impact the decision to broadly implement clinical molecular genetic testing in CVMs. Major benefits of testing include establishing a genetic diagnosis, facilitating cost-effective screening of family members who may have subclinical disease, predicting recurrence risk in offsprings, enabling early diagnosis and anticipatory management of CV and non-CV disease phenotypes, predicting long-term outcomes, and facilitating the development of novel therapies aimed at disease improvement or prevention. Limitations include financial cost, psychosocial cost, and ambiguity of interpretation of results. Multiplex families and patients with syndromic features are two groups where disease causation could potentially be firmly established. However, these account for the minority of the overall CVM population, and there is increasing recognition that genotypes previously associated with syndromes also exist in patients who lack non-CV findings. In all circumstances, ongoing dialog between cardiologists and clinical geneticists will be needed to accurately interpret genetic testing and improve these patients’ health. This may be most effectively implemented by the creation and support of CV genetics services at centers committed to pursuing testing for patients. PMID:27504451

  2. Testing the semi-explicit assembly model of aqueous solvation in the SAMPL4 challenge.

    PubMed

    Li, Libo; Dill, Ken A; Fennell, Christopher J

    2014-03-01

    Here, we test a method, called semi-explicit assembly (SEA), that computes the solvation free energies of molecules in water in the SAMPL4 blind test challenge. SEA was developed with the intention of being as accurate as explicit-solvent models, but much faster to compute. It is accurate because it uses pre-simulations of simple spheres in explicit solvent to obtain structural and thermodynamic quantities, and it is fast because it parses solute free energies into regionally additive quantities. SAMPL4 provided us the opportunity to make new tests of SEA. Our tests here lead us to the following conclusions: (1) The newest version, called Field-SEA, which gives improved predictions for highly charged ions, is shown here to perform as well as the earlier versions (dipolar and quadrupolar SEA) on this broad blind SAMPL4 test set. (2) We find that both the past and present SEA models give solvation free energies that are as accurate as TIP3P. (3) Using a new approach for force field parameter optimization, we developed improved hydroxyl parameters that ensure consistency with neat-solvent dielectric constants, and found that they led to improved solvation free energies for hydroxyl-containing compounds in SAMPL4. We also learned that these hydroxyl parameters are not just fixing solvent exposed oxygens in a general sense, and therefore do not improve predictions for carbonyl or carboxylic-acid groups. Other such functional groups will need their own independent optimizations for potential improvements. Overall, these tests in SAMPL4 indicate that SEA is an accurate, general and fast new approach to computing solvation free energies.

  3. Serological, intradermal and live flea challenge tests in the assessment of hypersensitivity to flea antigens in cats (Felis domesticus).

    PubMed

    Bond, Ross; Hutchinson, Melanie J; Loeffler, Anette

    2006-09-01

    The results of intradermal testing with three commercial flea antigens and a serological test for IgE antibodies to flea antigens were compared with live flea challenge in cats. Eight control cats with no prior flea exposure had negative serological test and flea challenge results. By contrast, 17 out of 27 cats with previous flea exposure showed immediate reactivity to flea challenge; reactivity at 6, 24 and 48 h after flea exposure was noted in 12, 16 and 21 cats, respectively. Seventeen of these cats had positive serological test results. Seven cats showed immediate intradermal test reactions to the ARTU allergen, six reacted to the Biophady allergen, and six reacted to the Greer allergen. Intradermal test reactivity was less frequent at the other time points. Using the results of the flea challenge as the 'gold standard' for the presence or absence of sensitisation to fleas, the sensitivity and specificity of the serological test was 0.88 and 0.77, respectively. Sensitivities of the intradermal tests at the four time points ranged from 0 to 0.33, whereas the specificities ranged from 0.78 to 1.0. Live flea challenge is better able to detect cats with hypersensitivity to fleas than either intradermal or serological testing.

  4. Addressing Challenges to the Design & Test of Operational Lighting Environments for the International Space Station

    NASA Technical Reports Server (NTRS)

    Clark, Toni A.

    2014-01-01

    In our day to day lives, the availability of light, with which to see our environment, is often taken for granted. The designers of land based lighting systems use sunlight and artificial light as their toolset. The availability of power, quantity of light sources, and variety of design options are often unlimited. The accessibility of most land based lighting systems makes it easy for the architect and engineer to verify and validate their design ideas. Failures with an implementation, while sometimes costly, can easily be addressed by renovation. Consider now, an architectural facility orbiting in space, 260 miles above the surface of the earth. This human rated architectural facility, the International Space Station (ISS) must maintain operations every day, including life support and appropriate human comforts without fail. The facility must also handle logistics of regular shipments of cargo, including new passengers. The ISS requires accommodations necessary for human control of machine systems. Additionally, the ISS is a research facility and supports investigations performed inside and outside its livable volume. Finally, the facility must support remote operations and observations by ground controllers. All of these architectural needs require a functional, safe, and even an aesthetic lighting environment. At Johnson Space Center, our Habitability and Human Factors team assists our diverse customers with their lighting environment challenges, via physical test and computer based analysis. Because of the complexity of ISS operational environment, our team has learned and developed processes that help ISS operate safely. Because of the dynamic exterior lighting environment, uses computational modeling to predict the lighting environment. The ISS' orbit exposes it to a sunrise every 90 minutes, causing work surfaces to quickly change from direct sunlight to earthshine to total darkness. Proper planning of vehicle approaches, robotics operations, and crewed

  5. Safety Testing of Dengue-1 and Dengue-3 Seeds for Human Challenges, Unattenuated. Dengue Virus Type 4

    DTIC Science & Technology

    1988-07-01

    o AD SAFETY TESTING OF DENGUE -1 AND DENGUE -3 SEEDS FOR HUMAN CHALLENGES, UNATTENUATED; DENGUE VIRUS TYPE 4 PHASE REPORT LOUIS POTASHELECTE - OCT 0...Classification) (U) Safety Testing of Dengue -] and Dengue -3 Seeds for Human Challenges, Unattenuated 12. PERSONAL AUTHOR(S) Potash, Louis 13a. TYPE OF REPORT...SUBJECT TERMS (Continue on reverse of necesary and identify by block number) FIELD GROUP SUB-GROUP,, \\" 06 13 Dengue -1; Dengue -3;’ epatitis A Viral

  6. Enhanced tolerability of the 5-hydroxytryptophane challenge test combined with granisetron.

    PubMed

    Jacobs, G E; Kamerling, I M C; de Kam, M L; Derijk, R H; van Pelt, J; Zitman, F G; van Gerven, J M A

    2010-01-01

    A recently developed oral serotonergic challenge test consisting of 5-Hydroxytryptophane (5-HTP, 200 mg) combined with carbidopa (CBD, 100 mg + 50 mg) exhibited dose-related neuroendocrine responsiveness and predictable pharmacokinetics. However, its applicability is limited by nausea and vomiting. A randomized, double-blind, placebo-controlled, four-way crossover trial was performed in 12 healthy male volunteers. The 5-HTP/CBD-challenge was combined with two oral anti-emetics (granisetron, 2 mg or domperidone, 10 mg) to investigate its reliability when side-effects are suppressed. The neuroendocrine response (serum cortisol and prolactin), the side-effect profile [Visual Analogue Scale Nausea (VAS)] and vomiting subjects per treatment were the main outcome measures. Compared to 5-HTP/CBD/placebo, 5-HTP/CBD/ granisetron had no impact on cortisol [% change with 95% confidence interval: -7.1% (18.9; 6.5)] or prolactin levels [-9.6% (-25.1; 9.1)]; 5-HTP/CBD/domperidone increased cortisol [+13.0% (-4.2; 33.4)], and increased prolactin extensively [+336.8% (245.7; 451.9)]. Compared to placebo, VAS Nausea increased non-significantly with granisetron [+7.6 mm (-1.3; 16.5)], as opposed to domperidone [+16.2 mm (7.2; 25.2)] and 5-HTP/CBD/placebo [+14.7 mm (5.5; 23.8)]. No subjects vomited with granisetron, compared to two subjects treated with 5-HTP/CBD/placebo and five subjects with domperidone. Compared with 5-HTP/CBD/placebo, granisetron addition decreased C(max) of 5-HTP statistically significantly different (from 1483 to 1272 ng/ml) without influencing AUC(0- infinity). Addition of granisetron to the combined 5-HTP/CBD challenge suppresses nausea and vomiting without influencing the neuroendocrine response or pharmacokinetics, enhancing its clinical applicability in future psychiatric research and drug development.

  7. [Interpretation and use of routine pulmonary function tests: Spirometry, static lung volumes, lung diffusion, arterial blood gas, methacholine challenge test and 6-minute walk test].

    PubMed

    Bokov, P; Delclaux, C

    2016-02-01

    Resting pulmonary function tests (PFT) include the assessment of ventilatory capacity: spirometry (forced expiratory flows and mobilisable volumes) and static volume assessment, notably using body plethysmography. Spirometry allows the potential definition of obstructive defect, while static volume assessment allows the potential definition of restrictive defect (decrease in total lung capacity) and thoracic hyperinflation (increase in static volumes). It must be kept in mind that this evaluation is incomplete and that an assessment of ventilatory demand is often warranted, especially when facing dyspnoea: evaluation of arterial blood gas (searching for respiratory insufficiency) and measurement of the transfer coefficient of the lung, allowing with the measurement of alveolar volume to calculate the diffusing capacity of the lung for CO (DLCO: assessment of alveolar-capillary wall and capillary blood volume). All these pulmonary function tests have been the subject of an Americano-European Task force (standardisation of lung function testing) published in 2005, and translated in French in 2007. Interpretative strategies for lung function tests have been recommended, which define abnormal lung function tests using the 5th and 95th percentiles of predicted values (lower and upper limits of normal values). Thus, these recommendations need to be implemented in all pulmonary function test units. A methacholine challenge test will only be performed in the presence of an intermediate pre-test probability for asthma (diagnostic uncertainty), which is an infrequent setting. The most convenient exertional test is the 6-minute walk test that allows the assessment of walking performance, the search for arterial desaturation and the quantification of dyspnoea complaint.

  8. Permeation Testing of Materials With Chemical Agents or Simulants (Swatch Testing)

    DTIC Science & Technology

    2013-08-05

    clothing or equipment that is new, with or without pretreatment (s), and/or material that was previously subjected to periods of wear under varying...V; liquid challenge/liquid permeation; L/L; swatch test; pretreatments ; static diffusion test; aerosol test; rain cabinet; mandrel 16. SECURITY...Simulants. ................................................................................. 18 4.6 Swatch Pretreatment

  9. Advantages and Challenges of Dried Blood Spot Analysis by Mass Spectrometry Across the Total Testing Process

    PubMed Central

    Zakaria, Rosita; Allen, Katrina J.; Koplin, Jennifer J.; Roche, Peter

    2016-01-01

    Introduction Through the introduction of advanced analytical techniques and improved throughput, the scope of dried blood spot testing utilising mass spectrometric methods, has broadly expanded. Clinicians and researchers have become very enthusiastic about the potential applications of dried blood spot based mass spectrometric applications. Analysts on the other hand face challenges of sensitivity, reproducibility and overall accuracy of dried blood spot quantification. In this review, we aim to bring together these two facets to discuss the advantages and current challenges of non-newborn screening applications of dried blood spot quantification by mass spectrometry. Methods To address these aims we performed a key word search of the PubMed and MEDLINE online databases in conjunction with individual manual searches to gather information. Keywords for the initial search included; “blood spot” and “mass spectrometry”; while excluding “newborn”; and “neonate”. In addition, databases were restricted to English language and human specific. There was no time period limit applied. Results As a result of these selection criteria, 194 references were identified for review. For presentation, this information is divided into: 1) clinical applications; and 2) analytical considerations across the total testing process; being pre-analytical, analytical and post-analytical considerations. Conclusions DBS analysis using MS applications is now broadly applied, with drug monitoring for both therapeutic and toxicological analysis being the most extensively reported. Several parameters can affect the accuracy of DBS measurement and further bridge experiments are required to develop adjustment rules for comparability between dried blood spot measures and the equivalent serum/plasma values. Likewise, the establishment of independent reference intervals for dried blood spot sample matrix is required. PMID:28149263

  10. Separating Cloud Forming Nuclei from Interstitial Aerosol

    SciTech Connect

    Kulkarni, Gourihar R.

    2012-09-12

    It has become important to characterize the physicochemical properties of aerosol that have initiated the warm and ice clouds. The data is urgently needed to better represent the aerosol-cloud interaction mechanisms in the climate models. The laboratory and in-situ techniques to separate precisely the aerosol particles that act as cloud condensation nuclei (CCN) and ice nuclei (IN), termed as cloud nuclei (CN) henceforth, have become imperative in studying aerosol effects on clouds and the environment. This review summarizes these techniques, design considerations, associated artifacts and challenges, and briefly discusses the need for improved designs to expand the CN measurement database.

  11. Tropospheric Aerosols

    NASA Astrophysics Data System (ADS)

    Buseck, P. R.; Schwartz, S. E.

    2003-12-01

    It is widely believed that "On a clear day you can see forever," as proclaimed in the 1965 Broadway musical of the same name. While an admittedly beautiful thought, we all know that this concept is only figurative. Aside from Earth's curvature and Rayleigh scattering by air molecules, aerosols - colloidal suspensions of solid or liquid particles in a gas - limit our vision. Even on the clearest day, there are billions of aerosol particles per cubic meter of air.Atmospheric aerosols are commonly referred to as smoke, dust, haze, and smog, terms that are loosely reflective of their origin and composition. Aerosol particles have arisen naturally for eons from sea spray, volcanic emissions, wind entrainment of mineral dust, wildfires, and gas-to-particle conversion of hydrocarbons from plants and dimethylsulfide from the oceans. However, over the industrial period, the natural background aerosol has been greatly augmented by anthropogenic contributions, i.e., those produced by human activities. One manifestation of this impact is reduced visibility (Figure 1). Thus, perhaps more than in other realms of geochemistry, when considering the composition of the troposphere one must consider the effects of these activities. The atmosphere has become a reservoir for vast quantities of anthropogenic emissions that exert important perturbations on it and on the planetary ecosystem in general. Consequently, much recent research focuses on the effects of human activities on the atmosphere and, through them, on the environment and Earth's climate. For these reasons consideration of the geochemistry of the atmosphere, and of atmospheric aerosols in particular, must include the effects of human activities. (201K)Figure 1. Impairment of visibility by aerosols. Photographs at Yosemite National Park, California, USA. (a) Low aerosol concentration (particulate matter of aerodynamic diameter less than 2.5 μm, PM2.5=0.3 μg m-3; particulate matter of aerodynamic diameter less than 10

  12. The Psychological Challenges of Replacing Conventional Karyotyping with Genomic SNP Array Analysis in Prenatal Testing.

    PubMed

    Riedijk, Sam; Diderich, Karin E M; van der Steen, Sanne L; Govaerts, Lutgarde C P; Joosten, Marieke; Knapen, Maarten F C M; de Vries, Femke A T; van Opstal, Diane; Tibben, Aad; Galjaard, Robert-Jan H

    2014-07-03

    Pregnant couples tend to prefer a maximum of information about the health of their fetus. Therefore, we implemented whole genome microarray instead of conventional karyotyping (CK) for all indications for prenatal diagnosis (PND). The array detects more clinically relevant anomalies, including early onset disorders, not related to the indication and more genetic anomalies of yet unquantifiable risk, so-called susceptibility loci (SL) for mainly neurodevelopmental disorders. This manuscript highlights the psychological challenges in prenatal genetic counselling when using the array and provides counselling suggestions. First, we suggest that pre-test decision counselling should emphasize deliberation about what pregnant couples wish to learn about the future health of their fetus more than information about possible outcomes. Second, pregnant couples need support in dealing with SL. Therefore, in order to consider the SL in a proportionate perspective, the presence of phenotypes associated with SL in the family, the incidence of a particular SL in control populations and in postnatally ascertained patients needs highlighting during post-test genetic counselling. Finally, the decision that couples need to make about the course of their pregnancy is more complicated when the expected phenotype is variable and not quantifiable. Therefore, during post-test psychological counseling, couples should concretize the options of continuing and ending their pregnancy; all underlying feelings and thoughts should be made explicit, as well as the couple's resources, in order to attain adequate decision-making. As such, pre- and post-test counselling aids pregnant couples in handling the uncertainties that may accompany offering a broader scope of genetic PND using the array.

  13. The Psychological Challenges of Replacing Conventional Karyotyping with Genomic SNP Array Analysis in Prenatal Testing

    PubMed Central

    Riedijk, Sam; Diderich, Karin E. M.; van der Steen, Sanne L.; Govaerts, Lutgarde C. P.; Joosten, Marieke; Knapen, Maarten F. C. M.; de Vries, Femke A. T.; van Opstal, Diane; Tibben, Aad; Galjaard, Robert-Jan H.

    2014-01-01

    Pregnant couples tend to prefer a maximum of information about the health of their fetus. Therefore, we implemented whole genome microarray instead of conventional karyotyping (CK) for all indications for prenatal diagnosis (PND). The array detects more clinically relevant anomalies, including early onset disorders, not related to the indication and more genetic anomalies of yet unquantifiable risk, so-called susceptibility loci (SL) for mainly neurodevelopmental disorders. This manuscript highlights the psychological challenges in prenatal genetic counselling when using the array and provides counselling suggestions. First, we suggest that pre-test decision counselling should emphasize deliberation about what pregnant couples wish to learn about the future health of their fetus more than information about possible outcomes. Second, pregnant couples need support in dealing with SL. Therefore, in order to consider the SL in a proportionate perspective, the presence of phenotypes associated with SL in the family, the incidence of a particular SL in control populations and in postnatally ascertained patients needs highlighting during post-test genetic counselling. Finally, the decision that couples need to make about the course of their pregnancy is more complicated when the expected phenotype is variable and not quantifiable. Therefore, during post-test psychological counseling, couples should concretize the options of continuing and ending their pregnancy; all underlying feelings and thoughts should be made explicit, as well as the couple’s resources, in order to attain adequate decision-making. As such, pre- and post-test counselling aids pregnant couples in handling the uncertainties that may accompany offering a broader scope of genetic PND using the array. PMID:26237473

  14. Mycobacterium tuberculosis drug-resistance testing: challenges, recent developments and perspectives.

    PubMed

    Schön, T; Miotto, P; Köser, C U; Viveiros, M; Böttger, E; Cambau, E

    2017-03-01

    Drug-resistance testing, or antimicrobial susceptibility testing (AST), is mandatory for Mycobacterium tuberculosis in cases of failure on standard therapy. We reviewed the different methods and techniques of phenotypic and genotypic approaches. Although multiresistant and extensively drug-resistant (MDR/XDR) tuberculosis is present worldwide, AST for M. tuberculosis (AST-MTB) is still mainly performed according to the resources available rather than the drug-resistance rates. Phenotypic methods, i.e. culture-based AST, are commonly used in high-income countries to confirm susceptibility of new cases of tuberculosis. They are also used to detect resistance in tuberculosis cases with risk factors, in combination with genotypic tests. In low-income countries, genotypic methods screening hot-spot mutations known to confer resistance were found to be easier to perform because they avoid the culture and biosafety constraint. Given that genotypic tests can rapidly detect the prominent mechanisms of resistance, such as the rpoB mutation for rifampicin resistance, we are facing new challenges with the observation of false-resistance (mutations not conferring resistance) and false-susceptibility (mutations different from the common mechanism) results. Phenotypic and genotypic approaches are therefore complementary for obtaining a high sensitivity and specificity for detecting drug resistances and susceptibilities to accurately predict MDR/XDR cure and to gather relevant data for resistance surveillance. Although AST-MTB was established in the 1960s, there is no consensus reference method for MIC determination against which the numerous AST-MTB techniques can be compared. This information is necessary for assessing in vitro activity and setting breakpoints for future anti-tuberculosis agents.

  15. Continued development and testing of a new thermodynamic aerosol module for urban and regional air quality models

    NASA Astrophysics Data System (ADS)

    Nenes, Athanasios; Pandis, Spyros N.; Pilinis, Christodoulos

    A computationally efficient and rigorous thermodynamic model (ISORROPIA) that predicts the physical state and composition of inorganic atmospheric aerosol is presented. The advantages of this particular model render it suitable for incorporation into urban and regional air quality models. The model is embodied into the UAM-AERO air quality model, and the performance is compared with two other thermodynamic modules currently in use, SEQUILIB 1.5 and SEQUILIB 2.1. The new model yields predictions that agree with experimental measurements and the results of the other models, but at the same time proves to be much faster and computationally efficient. Using ISORROPIA accelerates the thermodynamic calculations by more than a factor of six, while the overall speed-up of UAM-AERO is at least twofold. This speedup is possible by the optimal solution of the thermodynamic equations, and the usage of precalculated tables, whenever possible.

  16. Challenges During Microstructural Analysis and Mechanical Testing of Small-Scale Pseudoelastic NiTi Structures

    NASA Astrophysics Data System (ADS)

    Hahn, S.; Wagner, M. F.-X.

    2016-06-01

    Most investigations on NiTi-based shape memory alloys involve large-scale bulk material; knowledge about the martensitic transformation in small-scale NiTi structures is still limited. In this paper, we study the microstructures of thin NiTi layers and their mechanical properties, and we discuss typical challenges that arise when experiments are performed on small samples. A physical vapor deposition (PVD) process was used to deposit thin NiTi wires with a cross section of 15 × 15 μm2 and dogbone-shaped samples 5 × 500 μm2. Microstructural properties were characterized by X-ray diffraction, electron backscatter diffraction, and scanning electron microscopy. Moreover, tensile tests were performed using optical strain measurements in order to observe martensite band formation during cyclic loading. The surfaces of the crystalline wires reflect the columnar growth of NiTi during deposition. The wires exhibit pseudoelastic material behavior during tensile testing. Fracture typically occurs along the columns because the column growth direction is perpendicular to the straining direction. Electropolishing removes these local stress raisers and hence increases fracture strains. Our results demonstrate that the pseudoelastic properties of the PVD-processed materials agree well with those of conventional NiTi, and that they provide new opportunities to study the fundamentals of martensitic transformation in small-scale model systems.

  17. Challenges of Pre- and Post-Test Counseling for Orthodox Jewish Individuals in the Premarital Phase.

    PubMed

    Rose, E; Schreiber-Agus, N; Bajaj, K; Klugman, S; Goldwaser, T

    2016-02-01

    The Jewish community has traditionally taken ownership of its health, and has taken great strides to raise awareness about genetic issues that affect the community, such as Tay-Sachs disease and Hereditary Breast and Ovarian Cancer syndrome. Thanks in part to these heightened awareness efforts, many Orthodox Jewish individuals are now using genetics services as they begin to plan their families. Due to unique cultural and religious beliefs and perceptions, the Orthodox Jewish patients who seek genetic counseling face many barriers to a successful counseling session, and often seek the guidance of programs such as the Program for Jewish Genetic Health (PJGH). In this article, we present clinical vignettes from the PJGH's clinical affiliate, the Reproductive Genetics practice at the Montefiore Medical Center. These cases highlight unique features of contemporary premarital counseling and screening within the Orthodox Jewish Community, including concerns surrounding stigma, disclosure, "marriageability," the use of reproductive technologies, and the desire to include a third party in decision making. Our vignettes demonstrate the importance of culturally-sensitive counseling. We provide strategies and points to consider when addressing the challenges of pre- and post-test counseling as it relates to genetic testing in this population.

  18. An objective approach for Burkholderia pseudomallei strain selection as challenge material for medical countermeasures efficacy testing.

    PubMed

    Van Zandt, Kristopher E; Tuanyok, Apichai; Keim, Paul S; Warren, Richard L; Gelhaus, H Carl

    2012-01-01

    Burkholderia pseudomallei is the causative agent of melioidosis, a rare disease of biodefense concern with high mortality and extreme difficulty in treatment. No human vaccines are available that protect against B. pseudomallei infection, and with the current limitations of antibiotic treatment, the development of new preventative and therapeutic interventions is crucial. Although clinical trials could be used to test the efficacy of new medical countermeasures (MCMs), the high mortality rates associated with melioidosis raises significant ethical issues concerning treating individuals with new compounds with unknown efficacies. The US Food and Drug Administration (FDA) has formulated a set of guidelines for the licensure of new MCMs to treat diseases in which it would be unethical to test the efficacy of these drugs in humans. The FDA "Animal Rule" 21 CFR 314 calls for consistent, well-characterized B. pseudomallei strains to be used as challenge material in animal models. In order to facilitate the efficacy testing of new MCMs for melioidosis using animal models, we intend to develop a well-characterized panel of strains for use. This panel will comprise of strains that were isolated from human cases, have a low passage history, are virulent in animal models, and are well-characterized phenotypically and genotypically. We have reviewed published and unpublished data on various B. pseudomallei strains to establish an objective method for selecting the strains to be included in the panel of B. pseudomallei strains with attention to five categories: animal infection models, genetic characterization, clinical and passage history, and availability of the strain to the research community. We identified 109 strains with data in at least one of the five categories, scored each strain based on the gathered data and identified six strains as candidate for a B. pseudomallei strain panel.

  19. Applications of UV Scattering and Absorbing Aerosol Indices

    NASA Astrophysics Data System (ADS)

    Penning de Vries, M.; Beirle, S.; Wagner, T.

    2009-04-01

    Aerosols cause a substantial amount of radiative forcing, but quantifying this amount is difficult: determining aerosol concentrations in the atmosphere and, especially, characterizing their (optical) properties, has proved to be quite a challenge. A good way to monitor aerosol characteristics on a global scale is to perform satellite remote sensing. Most satellite aerosol retrieval algorithms are based on fitting of aerosol-induced changes in earth reflectance, which are usually subtle and have a smooth wavelength dependence. In such algorithms certain aerosol models are assumed, where optical parameters such as single scattering albedo, asymmetry parameter and size parameter (or Angstrom exponent) are defined. Another, semi-quantitative technique for detecting aerosols is the calculation of UV Aerosol Indices (UVAI). The Absorbing and Scattering Aerosol Indices detect "UV-absorbing" aerosols (most notably mineral dust, black and brown carbon particles) and "scattering" aerosols (sulfate and secondary organic aerosol particles), respectively. UVAI are essentially a measure of the contrast between two wavelengths in the UV range. The advantages of UVAI are: they can be determined in the presence of clouds, they are rather insensitive to surface type, and they are very sensitive to aerosols. The Absorbing Aerosol Index (AAI) has been in use for over a decade, and the Scattering Aerosol Index (SAI) was recently introduced by our group. Whereas the AAI is mainly used to detect desert dust and biomass burning plumes, the SAI can be used to study regions with high concentrations of non-absorbing aerosols, either anthropogenic (e.g. sulfate aerosols in eastern China) or biogenic (e.g. secondary organic aerosols formed from VOCs emitted by plants). Here we will present our recent UVAI results from SCIAMACHY: we will discuss the seasonal trend of SAI, and correlate our UVAI data with other datasets such as trace gases (HCHO, NO2, CO) and fire counts from the (A

  20. Detecting Lung Diseases from Exhaled Aerosols: Non-Invasive Lung Diagnosis Using Fractal Analysis and SVM Classification

    PubMed Central

    Xi, Jinxiang; Zhao, Weizhong; Yuan, Jiayao Eddie; Kim, JongWon; Si, Xiuhua; Xu, Xiaowei

    2015-01-01

    Background Each lung structure exhales a unique pattern of aerosols, which can be used to detect and monitor lung diseases non-invasively. The challenges are accurately interpreting the exhaled aerosol fingerprints and quantitatively correlating them to the lung diseases. Objective and Methods In this study, we presented a paradigm of an exhaled aerosol test that addresses the above two challenges and is promising to detect the site and severity of lung diseases. This paradigm consists of two steps: image feature extraction using sub-regional fractal analysis and data classification using a support vector machine (SVM). Numerical experiments were conducted to evaluate the feasibility of the breath test in four asthmatic lung models. A high-fidelity image-CFD approach was employed to compute the exhaled aerosol patterns under different disease conditions. Findings By employing the 10-fold cross-validation method, we achieved 100% classification accuracy among four asthmatic models using an ideal 108-sample dataset and 99.1% accuracy using a more realistic 324-sample dataset. The fractal-SVM classifier has been shown to be robust, highly sensitive to structural variations, and inherently suitable for investigating aerosol-disease correlations. Conclusion For the first time, this study quantitatively linked the exhaled aerosol patterns with their underlying diseases and set the stage for the development of a computer-aided diagnostic system for non-invasive detection of obstructive respiratory diseases. PMID:26422016

  1. The physiological consequences of crib-biting in horses in response to an ACTH challenge test.

    PubMed

    Briefer Freymond, S; Bardou, D; Briefer, E F; Bruckmaier, R; Fouché, N; Fleury, J; Maigrot, A-L; Ramseyer, A; Zuberbühler, K; Bachmann, I

    2015-11-01

    Stereotypies are repetitive and relatively invariant patterns of behavior, which are observed in a wide range of species in captivity. Stereotypic behavior occurs when environmental demands produce a physiological response that, if sustained for an extended period, exceeds the natural physiological regulatory capacity of the organism, particularly in situations that include unpredictability and uncontrollability. One hypothesis is that stereotypic behavior functions to cope with stressful environments, but the existing evidence is contradictory. To address the coping hypothesis of stereotypies, we triggered physiological reactions in 22 horses affected by stereotypic behavior (crib-biters) and 21 non-crib-biters (controls), using an ACTH challenge test. Following administration of an ACTH injection, we measured saliva cortisol every 30 min and heart rate (HR) continuously for a period of 3h. We did not find any differences in HR or HR variability between the two groups, but crib-biters (Group CB) had significantly higher cortisol responses than controls (Group C; mean ± SD: CB, 5.84 ± 2.62 ng/ml, C, 4.76 ± 3.04 ng/ml). Moreover, crib-biters that did not perform the stereotypic behavior during the 3-hour test period (Group B) had significantly higher cortisol levels than controls, which was not the case of crib-biters showing stereotypic behavior (Group A) (B, 6.44 ± 2.38 ng/ml A, 5.58 ± 2.69 ng/ml). Our results suggest that crib-biting is a coping strategy that helps stereotypic individuals to reduce cortisol levels caused by stressful situations. We conclude that preventing stereotypic horses from crib-biting could be an inappropriate strategy to control this abnormal behavior, as it prevents individuals from coping with situations that they perceive as stressful.

  2. Oxygen challenge test in septic shock patients: prognostic value and influence of respiratory status.

    PubMed

    Mari, Arnaud; Vallée, Fabrice; Bedel, Jérome; Riu, Béatrice; Ruiz, Jean; Sanchez-Verlaan, Pascale; Geeraerts, Thomas; Génestal, Michèle; Silva, Stein; Fourcade, Olivier

    2014-06-01

    Transcutaneous oxygen pressure (PtcO2) value in response to an increase of FiO2 or oxygen challenge test (OCT) in ventilated patients has been reported to be related to peripheral perfusion and outcome during septic shock. However, patients with sepsis-related acute respiratory distress syndrome could demonstrate compromised arterial oxygenation with OCT impairment decoupled to circulatory failure. The aims of this study were to confirm the prognostic value of OCT and to explore the influence of respiratory status on OCT results. This was a prospective study set in an intensive care unit of a tertiary teaching hospital. Fifty-six mechanically ventilated patients with septic shock criteria were studied. Transcutaneous oxygen pressure was measured at baseline and after OCT, at intensive care unit admittance (T0), and 24 h later (T24). Survival at day 28 and hemodynamic and respiratory parameters were analyzed and compared according to outcome and respiratory status. Central hemodynamic parameters or static transcutaneous data did not differ between survivors and nonsurvivors at enrollment. The OCT was statistically different at T24 according to outcome (P < 0.001), but sensitivity was low (53%). Moreover, patients with low OCT results at T24 exhibited more severe respiratory failure (P < 0.01). The OCT at T24 is related to outcome but is influenced by the severity of respiratory failure. Our results suggest considering with caution hemodynamic management based on OCT in septic shock patients with altered pulmonary function.

  3. Manufacturing and test of 2G-HTS coils for rotating machines: Challenges, conductor requirements, realization

    NASA Astrophysics Data System (ADS)

    Oomen, Marijn; Herkert, Werner; Bayer, Dietmar; Kummeth, Peter; Nick, Wolfgang; Arndt, Tabea

    2012-11-01

    We investigate the use of 2nd-generation High-Temperature Superconductors (2G-HTSs) in the rotors of electrical motors and generators. For these devices the conductor must be wound into robust impregnated coils, which are operated in vacuum at temperatures around 30 K, in strong magnetic fields of about 2T. Differences in thermal contraction between the coil former, conductor constituents, impregnation resin, bandage and heat-sink materials (assembled at room temperature) cause mechanical stresses at operating temperature. Rotating-machine operation adds Lorentz forces and challenging centripetal accelerations up to thousands of g. Second generation-HTS conductors withstand large tensile stresses in axial direction and compression in normal direction. However, shear stresses, axial compression, and tension normal to the conductor can cause degradation in superconducting properties. Such stresses can be mitigated by correct choice of materials, coil lay-out and manufacturing process. A certain stress level will remain, which the conductor must withstand. We have manufactured many impregnated round and race-track coils, using different 2G-HTS conductors, and tested them at temperatures from 25 K to 77 K. Degradation of the superconductor in early coils was traced to the mentioned differences in thermal contraction, and was completely avoided in coils produced later. We will discuss appropriate coil-winding techniques to assure robust and reliable superconductor performance.

  4. Breast cancer predictive factor testing: the challenges and importance of standardizing tissue handling.

    PubMed

    Hicks, David G; Kushner, LeeAnn; McCarthy, Kristin

    2011-01-01

    The introduction of breast biomarkers into clinical practice and their critically important role in adjuvant treatment decisions has created new challenges for the surgical pathology laboratory. In most institutions, the current standards for collection and preservation of clinical samples have been in place for decades and have focused on tissue preservation for morphologic examination, with little if any attention paid to preserving the quality of macromolecules that may be in the tissue. Because of the importance of these markers for determining the most appropriate treatments available for each patient, there is a need for standardizing pre-analytic variables, with the goal of developing standardized methods of tissue procurement and processing, and documenting how these variables affect the quality of tissue for biomarker testing and molecular analysis. By better defining specimen handling requirements and approaching diagnostic tissue samples as analytes, we can improve the quality of routine diagnostic samples, which in turn will enhance adjuvant treatment decisions when dealing with breast cancer and other solid tumor malignancies. The quality of archival tissue samples for future biomarker research will also benefit.

  5. Design challenges encountered in the F-15 PCA flight test program

    NASA Technical Reports Server (NTRS)

    Maine, Trindel A.; Burcham, Frank W., Jr.; Schaefer, Peter; Burken, John

    1995-01-01

    The NASA Dryden Flight Research Center conducted flight tests of a propulsion-controlled aircraft system on an F-15 airplane. This system was designed to explore the feasibility of providing safe emergency landing capability using only the engines to provide flight control in the event of a catastrophic loss of conventional flight controls. Control laws were designed to control the flight path and bank angle using only commands to the throttles. While the program was highly successful, this paper concentrates on the challenges encountered using engine thrust as the only control effector. Compared to conventional flight control surfaces, the engines are slow, nonlinear, and have limited control effectiveness. This increases the vulnerability of the system to outside disturbances and changes in aerodynamic conditions. As a result, the PCA system had problems with gust rejection. Cross coupling of the longitudinal and lateral axis also occured, primarily as a result of control saturation. The normally negligible effects of inlet airframe interactions became significant with the engines as the control effector. Flight and simulation data are used to illustrate these difficulties.

  6. Serological assays as alternatives to the Ph Eur challenge test for batch release of tetanus vaccines for human use.

    PubMed

    Winsnes, R; Hendriksen, C; Sesardic, D; Akkermans, A; Daas, A

    1999-01-01

    According to the European Pharmacopoeia (Ph Eur) monograph on Tetanus Vaccine (adsorbed) (1997: 0452), assessment of potency is based on a challenge test in guinea pigs or mice. The end-point is taken as paralysis or death. The test requires a large number of animals and causes severe distress. The aim of the present study was to refine the test, and reduce the number of animals needed, for batch release purposes. Serological assays having the potential of being internationally accepted, have been compared with Ph Eur assays. The study included five tetanus vaccines of various combinations and produced by different manufacturers. The results indicated an excellent correlation between enzyme-linked immunosorbent assay (ELISA) and the challenge test (about 93% predictive value), as well as between the toxin binding inhibition (ToBI) test and the challenge test (about 95% predictive value) and between ELISA and the ToBI test (r = 0.92). Antitoxin concentrations determined by ELISA and ToBI were generally in the same range. An overall good correlation was also seen for serum pools of the guinea pigs injected with equal vaccine doses, between toxin neutralisation test in mice (TNT) and ELISA (r = 0.93) as well as between TNT and ToBI (r = 0.97). The ultimate goal of this project was to determine whether serological assays can be used for testing combined vaccines, particularly for tetanus and diphtheria components, using sera from the same animals.

  7. Safety Testing of Dengue-1 and Dengue-3 Seeds for Human Challenges, Unattenuated; Hepatitis A Virus, Strain HM-175

    DTIC Science & Technology

    1989-06-01

    q j. AD 00 CSAFETY TESTING OF DENGUE -1 AND DENGUE -3 SEEDS FOR HUMAN CHALLENGES, UNATTENUATED; 0HEPATITIS A VIRUS, STRAIN HM-1750 FINAL REPORT By D...TITLE (Include Scurrty Classifcation)627A 27A8JC09 (U) Safety Testing of Dengue -1 and Dengue -3 Seeds for Human Challenges, Unattenuatei; Hepatitis A...necenary and identify by block number) 06EL GR3U Dengue -1; Dengue -3; Hepatitis A; Viral seeds; Vaccine; PA-1 06 03 I 1 ABSTRACT (Continue On reverse it

  8. Sensitization to Food Additives in Patients with Allergy: A Study Based on Skin Test and Open Oral Challenge.

    PubMed

    Moghtaderi, Mozhgan; Hejrati, Zinatosadat; Dehghani, Zahra; Dehghani, Faranak; Kolahi, Niloofar

    2016-06-01

    There has been a great increase in the consumption of various food additives in recent years. The purpose of this study was to identify the incidence of sensitization to food additives by using skin prick test in patients with allergy and to determine the concordance rate between positive skin tests and oral challenge in hypersensitivity to additives. This cross-sectional study included 125 (female 71, male 54) patients aged 2-76 years with allergy and 100 healthy individuals. Skin tests were performed in both patient and control groups with 25 fresh food additives. Among patients with allergy, 22.4% showed positive skin test at least to one of the applied materials. Skin test was negative to all tested food additives in control group. Oral food challenge was done in 28 patients with positive skin test, in whom 9 patients showed reaction to culprit (Concordance rate=32.1%). The present study suggested that about one-third of allergic patients with positive reaction to food additives showed positive oral challenge; it may be considered the potential utility of skin test to identify the role of food additives in patients with allergy.

  9. Development of algorithm for retrieving aerosols over land surfaces from NEMO-AM polarized measurements

    NASA Astrophysics Data System (ADS)

    Pandya, Mehul R.

    2016-04-01

    Atmospheric aerosols have a large effect on the Earth radiation budget through its direct and indirect effects. A systematic assessment of aerosol effects on Earth's climate requires global mapping of tropospheric aerosols through satellite remote sensing. However aerosol retrieval over land surface remains a challenging task due to bright background of the land surfaces. Polarized measurements can provide an improved aerosol sensing by providing a means of decoupling the surface and atmospheric contribution. The Indian Space Research Organisation has planned a Multi- Angle Dual-Polarization Instrument (MADPI) onboard a Nano satellite for Earth Monitoring & Observations for Aerosol Monitoring (NEMO-AM). MADPI has three spectral bands in blue, red and near infrared spectral regions with a nominal spatial resolution of 30 m from an altitude of 500 km polar orbit. A study has been taken up with the aim of development of an algorithm for retrieving aerosol optical thickness (AOT) over land surfaces from NEMO-AM polarized measurements. The study has three major components: (1) detailed theoretical modelling exercise for computing the atmospheric and surface polarized contributions, (2) modelling of total satellite-level polarized contribution, and (3) retrieval of aerosol optical thickness (AOT) by comparing the modelled and measured polarized signals. The algorithm has been developed for MADPI/NEMO-AM spectral bands and tested successfully on similar spectral bands of POLDER/PARASOL measurements to retrieve AOT over Indian landmass having diverse atmospheric conditions. POLDER-derived AOT fields were compared with MODIS-AOT products. Results showed a very good match (R2 0.69, RMSE 0.07). Initial results have provided encouraging results, however, comprehensive analysis and testing has to be carried out for establishing the proposed algorithm for retrieving AOT from NEMO-AM measurements.

  10. Up to the Challenge: SLA Commits to New Tools and Techniques to Ace Old Tests

    ERIC Educational Resources Information Center

    Blumenstein, Lynn

    2007-01-01

    According to conference co-chair Ty Webb, this year's Special Libraries Association (SLA) conference theme, "Climb to New Heights," challenges the info pro to "accept challenges by creating innovative solutions." To meet that need, conference programming, which runs June 3-6 in Denver, includes SYNERGY sessions, which are based on the…

  11. ENCAPSULATED AEROSOLS

    DTIC Science & Technology

    materials determine the range of applicability of each method. A useful microencapsulation method, based on coagulation by inertial force was developed...The generation apparatus, consisting of two aerosol generators in series, was utilized to produce many kinds of microcapsules . A fluid energy mill...was found useful for the production of some microcapsules . The permeability of microcapsule films and the effect of exposure time and humidity were

  12. The Water Framework Directive: The Challenges of Testing and Validation of Guidance Documents

    NASA Astrophysics Data System (ADS)

    Barth, F.; Bidoglio, G.; Murray, C. N.; Zaldivar, J.; Bouraoui, F.

    On the 23rd October 2000 the European Parliament and Council passed a Directive establishing a framework of community action in the field of water policy (Water Framework Directive- FWD). The Water Framework Directive (FWD) raises major challenges, these include an extremely demanding timetable, in particular in the nine preparatory years; the complexity of the text and the diversity of possible solutions to scientific, technical and practical questions. A further problem is that a common understanding and methodologies for the application of the different areas of the FWD do not necessarily exist. Member States have, historically, developed approaches to monitoring, impact assessment, economic analysis etc. that will need to be compared in order to be certain that they provide comparable level of results over the range of ecosystems covered in the European Union. Accession Countries will also have to start to adjust their environmental legislation to be compatible with EU Directives and standards. The Framework Water Directive imposes a series of deadlines for the reporting by Member States to the European Commission. In order to respond to this problem a Common Strategy on the Implementation of the Water Framework Directive is being developed by the European Commission and Member States. The aim of the development of this Common Strategy is to allow, as far as possible, a coherent and harmonious implementation of the Directive. Focus is on methodological questions related to a common understanding of the technical and scientific implications of the Directive. The aim is to clarify and develop, where appropriate, supporting technical and scientific information to assist in the practical implementation of the Directive. Guidance documents, advice for operational methods and other supporting documents will be developed for this purpose. A modular structure has been chosen for the overall strategy. The main modules are the key activities for the implementation

  13. A satellite view of the direct effect of aerosols on solar radiation at global scale

    NASA Astrophysics Data System (ADS)

    Hatzianastassiou, Nikolaos; Papadimas, Christos D.; Matsoukas, Christos; Fotiadi, Aggeliki; Benas, Nikolaos; Vardavas, Ilias

    2016-04-01

    Aerosols are a key parameter for better understanding and predicting current and future climate change. They are determining, apart from clouds, patterns of solar radiation through scattering and absorption processes. Especially, under cloud-free skies, aerosols are the major modulator of the solar radiation budget of the Earth-atmosphere system. Although significant improvement has been made as to better understanding the direct radiative effect (DRE) of aerosols, there is still a need for further improvement in our knowledge of the DRE spatial and temporal patterns, in particular with respect to extended spatial and temporal coverage of relevant information. In an ongoing rapidly evolving era of great satellite-based achievements, concerning the knowledge of solar radiation budget and its modulators, and with the great progress in obtaining significant information on key aerosol optical properties needed for modeling DRE, it is a great challenge to use all this new aerosol information and to see what is the new acquired scientific knowledge. The objective of this study is to obtain an improved view of global aerosol DRE effects using contemporary accurate data for the important atmospheric and surface parameters determining the solar radiation budget, with emphasis to state of the art aerosol data. Thus, a synergy is made of different datasets providing the necessary input data and of a detailed spectral radiative transfer model (RTM) to compute spectral globally distributed aerosol DREs. Emphasis is given on using highly accurate and well-tested aerosol optical properties. Spectral information on aerosol optical depth (AOD) is taken from retrieved products of the MODerate resolution Imaging Spectroradiometer (MODIS) instrument, while similar information is taken from MODIS for the aerosol asymmetry parameter (AP) over ocean. Information from MODIS is also taken for the aerosol single scattering albedo (SSA). All this information comes from the latest Collection

  14. Surface tension depression by low-solubility organic material in aqueous aerosol mimics

    NASA Astrophysics Data System (ADS)

    Schwier, Allison; Mitroo, Dhruv; McNeill, V. Faye

    2012-07-01

    Surface-active material, including long-chain fatty acids (LCFAs), comprises a significant fraction of organic aerosol mass. Surface-active species are thought to form a film at the gas-aerosol interface, with implications for aerosol heterogeneous chemistry and cloud formation. However, LCFA phase behavior and surface-bulk partitioning has not been characterized under most conditions typical of tropospheric aerosol water (i.e. acidic, high ionic content), making it challenging to predict surface film formation in aerosols. In this study, we present measurements of the surface tension of aqueous solutions containing the slightly soluble LCFAs oleic and stearic acid. The effect of varying pH, organic concentration, and inorganic salt content was tested for each system. We observe surface tension depression compared to water of up to ˜30 and 45% for aqueous solutions containing stearic or oleic acid at pH 0-8 and high inorganic salt concentrations (NaCl and (NH4)2SO4). This suggests that surface film formation is favorable for these species in atmospheric aerosols.

  15. Five myofibrillar lesion types in eccentrically challenged, unloaded rat adductor longus muscle--a test model

    NASA Technical Reports Server (NTRS)

    Thompson, J. L.; Balog, E. M.; Fitts, R. H.; Riley, D. A.

    1999-01-01

    Sarcomere disruptions are observed in the adductor longus (AL) muscles following voluntary reloading of spaceflown and hindlimb suspension unloaded (HSU) rat, which resemble lesions in eccentrically challenged muscle. We devised and tested an eccentric contraction (ECCON) test system for the 14-day HSU rat AL. Six to 7 hours following ECCON, ALs were fixed to allow immunostaining and electron microscopy (EM). Toluidine blue-stained histology semithin sections were screened for lesion density (#/mm2). Serial semithin sections from the ECCON group were characterized for myosin immunointensity of lesions. Five myofibrillar lesion types were identified in histological semithin sections: focal contractions; wide A-bands; opaque areas; missing A-bands; and hyperstretched sarcomeres. Lesion density by type was greater for ECCON than NonECCON ALs (P< or =0.05; focal contractions and opaque regions). Lesion density (#-of-all-five-types/mm2) was significantly different (ECCON: 23.91+/-10.58 vs. NonECCON: 5.48+/-1.28, P< or =0.05; ECCON vs. SHAM: 0.00+/-0.00; P< or = 0.025). PostECCON optimal tension decreased (Poi-drop, 17.84+/-4.22%) and was correlated to lesion density (R2=0.596), but prestretch tension demonstrated the highest correlation with lesion density (R2=0.994). In lesions, the darkly staining A-band lost the normally organized thick filament alignment to differing degrees across the different lesion types. Ranking the five lesion types by a measure of lesion length deformation (hypercontracted to hyperstretched) at the light microscopy level, related to the severity of thick filament registry loss across the lesion types at the electron microscopic level. This ranking suggested that the five lesion types seen in semithin sections at the light level represented a lesion progression sequence and paralleled myosin immunostaining loss as the distorted A-band filaments spread across the hyperlengthening lesion types. Lesion ultrastructure indicated damage involved

  16. Toxicity of atmospheric aerosols on marine phytoplankton

    PubMed Central

    Paytan, Adina; Mackey, Katherine R. M.; Chen, Ying; Lima, Ivan D.; Doney, Scott C.; Mahowald, Natalie; Labiosa, Rochelle; Post, Anton F.

    2009-01-01

    Atmospheric aerosol deposition is an important source of nutrients and trace metals to the open ocean that can enhance ocean productivity and carbon sequestration and thus influence atmospheric carbon dioxide concentrations and climate. Using aerosol samples from different back trajectories in incubation experiments with natural communities, we demonstrate that the response of phytoplankton growth to aerosol additions depends on specific components in aerosols and differs across phytoplankton species. Aerosol additions enhanced growth by releasing nitrogen and phosphorus, but not all aerosols stimulated growth. Toxic effects were observed with some aerosols, where the toxicity affected picoeukaryotes and Synechococcus but not Prochlorococcus. We suggest that the toxicity could be due to high copper concentrations in these aerosols and support this by laboratory copper toxicity tests preformed with Synechococcus cultures. However, it is possible that other elements present in the aerosols or unknown synergistic effects between these elements could have also contributed to the toxic effect. Anthropogenic emissions are increasing atmospheric copper deposition sharply, and based on coupled atmosphere–ocean calculations, we show that this deposition can potentially alter patterns of marine primary production and community structure in high aerosol, low chlorophyll areas, particularly in the Bay of Bengal and downwind of South and East Asia. PMID:19273845

  17. Toxicity of atmospheric aerosols on marine phytoplankton

    USGS Publications Warehouse

    Paytan, A.; Mackey, K.R.M.; Chen, Y.; Lima, I.D.; Doney, S.C.; Mahowald, N.; Labiosa, R.; Post, A.F.

    2009-01-01

    Atmospheric aerosol deposition is an important source of nutrients and trace metals to the open ocean that can enhance ocean productivity and carbon sequestration and thus influence atmospheric carbon dioxide concentrations and climate. Using aerosol samples from different back trajectories in incubation experiments with natural communities, we demonstrate that the response of phytoplankton growth to aerosol additions depends on specific components in aerosols and differs across phytoplankton species. Aerosol additions enhanced growth by releasing nitrogen and phosphorus, but not all aerosols stimulated growth. Toxic effects were observed with some aerosols, where the toxicity affected picoeukaryotes and Synechococcus but not Prochlorococcus.We suggest that the toxicity could be due to high copper concentrations in these aerosols and support this by laboratory copper toxicity tests preformed with Synechococcus cultures. However, it is possible that other elements present in the aerosols or unknown synergistic effects between these elements could have also contributed to the toxic effect. Anthropogenic emissions are increasing atmospheric copper deposition sharply, and based on coupled atmosphere-ocean calculations, we show that this deposition can potentially alter patterns of marine primary production and community structure in high aerosol, low chlorophyll areas, particularly in the Bay of Bengal and downwind of South and East Asia.

  18. Potency testing of veterinary rabies vaccines: replacement of challenge by in vitro testing: considerations for development of alternative assays.

    PubMed

    Lewis, C E; Fry, A M; Hermann, J R; Siev, D; Dusek, D M; Gatewood, D M

    2012-01-01

    Vaccination of domestic animals against rabies creates a critical barrier between wildlife reservoirs and the human population. Ensuring these vaccines are potent and effective is paramount in preventing human exposure to this deadly and costly disease. The National Institutes of Health (NIH) test is, at present, the most widely used and internationally recommended potency assay for batch testing inactivated rabies vaccines. This test has numerous inherent limitations and disadvantages, including a lack of precision. The NIH test requires a large number of animals and involves unrelieved pain and suffering. A relevant in vitro assay should provide a more accurate, reproducible, rapid, safe, and humane rabies vaccine potency test.

  19. Challenging Behavior in Smith-Lemli-Opitz Syndrome: Initial Test of Biobehavioral Influences

    PubMed Central

    Freeman, Kurt A.; Eagle, Rose; Merkens, Louise S.; Sikora, Darryn; Pettit-Kekel, Kersti; Nguyen-Driver, Mina; Steiner, Robert D.

    2013-01-01

    Objective To study challenging behavior (destruction, aggression, self-injury, stereotypy) in children with Smith-Lemli-Opitz syndrome (SLOS) using a biobehavioral model that helps distinguish biological from socially mediated variables influencing the behavior. Background SLOS is an autosomal-recessive syndrome of multiple malformations and intellectual disability resulting from a genetic error in cholesterol synthesis in all cells and tissues, including brain. The exact cause of the challenging behavior in SLOS is unclear, but defective brain cholesterol synthesis may contribute. Because the precise genetic and biochemical etiology of SLOS is known, this disorder is a good model for studying biological causes of challenging behavior. Method In a preliminary application of a biobehavioral model, we studied the association between cholesterol levels (as a biochemical indicator of disease severity) and behavior subtype (“biological” vs “learned”) in 13 children with SLOS. Parents completed a questionnaire that categorized challenging behavior as influenced primarily by social or nonsocial (thus, presumably biological) factors. Results The severity of the cholesterol synthesis defect correlated significantly with behavior subtype classification for 1 of 2 challenging behaviors. Greater severity of the cholesterol synthesis defect was associated with behavior being classified as primarily influenced by biological factors. Conclusion The interplay between challenging behavior and defective cholesterol synthesis in SLOS may help explain biological influences on the behavior. Our findings have implications for research on the effectiveness of behavioral and medical treatments for behavioral difficulties in SLOS and other neurodevelopmental disorders. PMID:23538569

  20. Remote Sensing of Aerosol and Non-Aerosol Absorption

    NASA Technical Reports Server (NTRS)

    Kaufman, Y. J.; Dubovik, O.; Holben, B. N.; Remer, L. A.; Tanre, D.; Lau, William K. M. (Technical Monitor)

    2001-01-01

    Remote sensing of aerosol from the new satellite instruments (e.g. MODIS from Terra) and ground based radiometers (e.g. the AERONET) provides the opportunity to measure the absorption characteristics of the ambient undisturbed aerosol in the entire atmospheric column. For example Landsat and AERONET data are used to measure spectral absorption of sunlight by dust from West Africa. Both Application of the Landsat and AERONET data demonstrate that Saharan dust absorption of solar radiation is several times smaller than the current international standards. This is due to difficulties of measuring dust absorption in situ, and due to the often contamination of dust properties by the presence of air pollution or smoke. We use the remotely sensed aerosol absorption properties described by the spectral sin le scattering albedo, together with statistics of the monthly optical thickness for the fine and coarse aerosol derived from the MODIS data. The result is an estimate of the flux of solar radiation absorbed by the aerosol layer in different regions around the globe where aerosol is prevalent. If this aerosol forcing through absorption is not included in global circulation models, it may be interpreted as anomalous absorption in these regions. In a preliminary exercise we also use the absorption measurements by AERONET, to derive the non-aerosol absorption of the atmosphere in cloud free conditions. The results are obtained for the atmospheric windows: 0.44 microns, 0.66 microns, 0.86 microns and 1.05 microns. In all the locations over the land and ocean that were tested no anomalous absorption in these wavelengths, was found within absorption optical thickness of +/- 0.005.

  1. Aerosol Modeling for the Global Model Initiative

    NASA Technical Reports Server (NTRS)

    Weisenstein, Debra K.; Ko, Malcolm K. W.

    2001-01-01

    The goal of this project is to develop an aerosol module to be used within the framework of the Global Modeling Initiative (GMI). The model development work will be preformed jointly by the University of Michigan and AER, using existing aerosol models at the two institutions as starting points. The GMI aerosol model will be tested, evaluated against observations, and then applied to assessment of the effects of aircraft sulfur emissions as needed by the NASA Subsonic Assessment in 2001. The work includes the following tasks: 1. Implementation of the sulfur cycle within GMI, including sources, sinks, and aqueous conversion of sulfur. Aerosol modules will be added as they are developed and the GMI schedule permits. 2. Addition of aerosol types other than sulfate particles, including dust, soot, organic carbon, and black carbon. 3. Development of new and more efficient parameterizations for treating sulfate aerosol nucleation, condensation, and coagulation among different particle sizes and types.

  2. Toll-like receptors are critical for clearance of Brucella and play different roles in development of adaptive immunity following aerosol challenge in mice.

    PubMed

    Pei, Jianwu; Ding, Xicheng; Fan, Yaping; Rice-Ficht, Allison; Ficht, Thomas A

    2012-01-01

    Brucella spp. cause undulant fever in humans and brucellosis in variety of other animals. Both innate and adaptive immunity have been shown to be important in controlling Brucella infection. Toll-like receptors (TLRs) represent a group of pattern recognition receptors (PRRs) that play critical roles in the host innate immune response, as well as development of adaptive immunity. In the current report, we investigated the role of TLR signaling in the clearance of Brucella and development of adaptive immunity in TLR2(-/-), TLR4(-/-), or MyD88(-/-) mice following aerosol exposure to B. melitensis 16 M. Consistent with previous reports, MyD88 is required for efficient clearance of Brucella from all three organs (lung, spleen, and liver). The results reveal Th2-skewed immune responses in TLR2(-/-) mice late in infection and support a TLR2 requirement for efficient clearance of Brucella from the lungs, but not from the spleen or liver. Similarly, TLR4 is required for efficient clearance of Brucella from the lung, but exhibits a minor contribution to clearance from the spleen and no demonstrable contribution to clearance from the liver. Lymphocyte proliferation assays suggest that the TLRs are not involved in the development of cell-mediated memory response to Brucella antigen. Antibody detection reveals that TLR2 and 4 are required to generate early antigen-specific IgG, but not during the late stages of infection. TLR2 and 4 are only transiently required for IgM production and not at all for IgA production. In contrast, MyD88 is essential for antigen specific IgG production late in infection, but is not required for IgM generation over the course of infection. Surprisingly, despite the prominent role for MyD88 in clearance from all tissues, MyD88-knockout mice express significantly higher levels of serum IgA. These results confirm the important role of MyD88 in controlling infection in the spleen while providing evidence of a prominent contribution to protection in

  3. Type of Aerosols Determination Over Malaysia by AERONET Data

    NASA Astrophysics Data System (ADS)

    Lim, H.; Tan, F.; Abdullah, K.; Holben, B. N.

    2013-12-01

    Aerosols are one of the most interesting studies by the researchers due to the complicated of their characteristic and are not yet well quantified. Besides that there still have huge uncertainties associated with changes in Earth's radiation budget. The previous study by other researchers shown a lot of difficulties and challenges in quantifying aerosol influences arise. As well as the heterogeneity from the aerosol loading and properties: spatial, temporal, size, and composition. In this study, we were investigated the aerosol characteristics over two regions with different environmental conditions and aerosol sources contributed. The study sites are Penang and Kuching, Malaysia where ground-based AErosol RObotic NETwork (AERONET) sun-photometer was deployed. The types of the aerosols for both study sites were identified by analyzing aerosol optical depth, angstrom parameter and spectral de-convolution algorithm product from sun-photometer. The analysis was carried out associated with the in-situ meteorological data of relative humidity, visibility and air pollution index. The major aerosol type over Penang found in this study was hydrophobic aerosols. Whereas the hydrophilic type of the aerosols was highly distributed in Kuching. The major aerosol size distributions for both regions were identified in this study. The result also shows that the aerosol optical properties were affected by the types and characteristic of aerosols. Therefore, in this study we generated an algorithm to determine the aerosols in Malaysia by considered the environmental factors. From this study we found that the source of aerosols should always being consider in to retrieve the accurate information of aerosol for air quality study.

  4. Aerosol polarization effects on atmospheric correction and aerosol retrievals in ocean color remote sensing.

    PubMed

    Wang, Menghua

    2006-12-10

    The current ocean color data processing system for the Sea-viewing Wide Field-of-View Sensor (SeaWiFS) and the moderate resolution imaging spectroradiometer (MODIS) uses the Rayleigh lookup tables that were generated using the vector radiative transfer theory with inclusion of the polarization effects. The polarization effects, however, are not accounted for in the aerosol lookup tables for the ocean color data processing. I describe a study of the aerosol polarization effects on the atmospheric correction and aerosol retrieval algorithms in the ocean color remote sensing. Using an efficient method for the multiple vector radiative transfer computations, aerosol lookup tables that include polarization effects are generated. Simulations have been carried out to evaluate the aerosol polarization effects on the derived ocean color and aerosol products for all possible solar-sensor geometries and the various aerosol optical properties. Furthermore, the new aerosol lookup tables have been implemented in the SeaWiFS data processing system and extensively tested and evaluated with SeaWiFS regional and global measurements. Results show that in open oceans (maritime environment), the aerosol polarization effects on the ocean color and aerosol products are usually negligible, while there are some noticeable effects on the derived products in the coastal regions with nonmaritime aerosols.

  5. Safety Testing of Dengue-1 and Dengue-3 Seeds for Human Challenges, Unattenuated; Hepatitis A Virus, Strain HM175

    DTIC Science & Technology

    1988-07-01

    AD SAFETY TESTING OF DENGUE -I AND DENGUE -3 SEEDS FOR HUMAN CHALLENGES, UNATrENUATED; HEPATITIS A VIRUS, STRAIN HM175 PHASE REPOR DTICcUUS PO.CASH{ I... Dengue -1 and Dengue -3 Seeds for Human Challenges, Unattenuated; Hepatitis A Virus. -Strain HM175 12. PERSONAL AUThOR(S) Potash, Louis 13&. TYPE OF...COSATI CODES ? B. SUBJECT TERMS (C~in0iU* an LIve i ec*ty arid identify by bdocir nunme) FIELD GROUP SU-GROUP 06 13 L Dengue -1; Dengue -3; Hepatitis A

  6. Characterization of aerosol events based on the column integrated optical aerosol properties and polarimetric measurements

    NASA Astrophysics Data System (ADS)

    Mandija, Florian; Markowicz, Krzysztof; Zawadzka, Olga

    2016-12-01

    Aerosol optical properties are very useful tools for analyzing their radiative effects, which are directly or indirectly related to the global radiation budget. Investigation of column-integrated aerosol optical properties is a worldwide and well-accepted method. The introduction of new methodologies, like those of operation with polarimetric measurements, represent a new challenge to interpret the measurement data and give more detailed information about the aerosol events and their characteristics. Aerosol optical properties during the period June - August 2015 in AERONET Strzyzow station in Poland were analyzed. The aerosol properties like aerosol optical depth, Ångström exponent, fine mode fraction, fine mode contribution on AOD, asymmetry parameter, single scattering angle are analyzed synergistically with the polarimetric measurements of the degree of polarization in different solar zenith and zenith viewing angles at several wavelengths. The overall results show that aerosol events in Strzyzow were characterized mostly by fine mode aerosols. Backward-trajectories suggest that the majority of air masses come from the west. The principal component of the aerosol load was urban/industrial contamination, especially from the inner part of the continent. Additionally, the maximal values of the degree of linear polarization were found to be dependent on the solar zenith and zenith viewing angles and aerosol optical properties like aerosol optical depth and Ångström exponent. These dependencies were further analyzed in a specific case with very high mean values of AOD500 (0.59) and AE440-870 (1.91). The diurnal variations of aerosol optical properties investigated during this special case, suggest that biomass burning products are the main cause of that aerosol load over the stations.

  7. Developments and Challenges in the Use of Computer-Based Testing for Assessing Second Language Ability

    ERIC Educational Resources Information Center

    Ockey, Gary J.

    2009-01-01

    Computer-based testing (CBT) to assess second language ability has undergone remarkable development since Garret (1991) described its purpose as "the computerized administration of conventional tests" in "The Modern Language Journal." For instance, CBT has made possible the delivery of more authentic tests than traditional paper-and-pencil tests.…

  8. Cross-institute evaluations of inhibitor-resistant PCR reagents for direct testing of aerosol and blood samples containing biological warfare agent DNA.

    PubMed

    Minogue, Timothy D; Rachwal, Phillip A; Trombley Hall, Adrienne; Koehler, Jeffery W; Weller, Simon A

    2014-02-01

    Rapid pathogen detection is crucial for the timely introduction of therapeutics. Two groups (one in the United Kingdom and one in the United States) independently evaluated inhibitor-resistant PCR reagents for the direct testing of substrates. In the United Kingdom, a multiplexed Bacillus anthracis (target) and Bacillus subtilis (internal-control) PCR was used to evaluate 4 reagents against 5 PCR inhibitors and down-selected the TaqMan Fast Virus 1-Step master mix (Life Technologies Inc.). In the United States, four real-time PCR assays (targeting B. anthracis, Brucella melitensis, Venezuelan equine encephalitis virus [VEEV], and Orthopoxvirus spp.) were used to evaluate 5 reagents (plus the Fast Virus master mix) against buffer, blood, and soil samples and down-selected the KAPA Blood Direct master mix (KAPA Biosystems Inc.) with added Platinum Taq (Life Technologies). The down-selected reagents underwent further testing. In the United Kingdom experiments, both reagents were tested against seven contrived aerosol collector samples containing B. anthracis Ames DNA and B. subtilis spores from a commercial formulation (BioBall). In PCR assays with reaction mixtures containing 40% crude sample, an airfield-collected sample induced inhibition of the B. subtilis PCR with the KAPA reagent and complete failure of both PCRs with the Fast Virus reagent. However, both reagents allowed successful PCR for all other samples-which inhibited PCRs with a non-inhibitor-resistant reagent. In the United States, a cross-assay limit-of-detection (LoD) study in blood was conducted. The KAPA Blood Direct reagent allowed the detection of agent DNA (by four PCRs) at higher concentrations of blood in the reaction mixture (2.5%) than the Fast Virus reagent (0.5%), although LoDs differed between assays and reagent combinations. Across both groups, the KAPA Blood Direct reagent was determined to be the optimal reagent for inhibition relief in PCR.

  9. Advanced Aerosol Sampling Technologies For Point Biodetection

    DTIC Science & Technology

    2004-11-17

    Impaction Aerosol Particle Behavior TAKE-HOME MESSAGE: Aerosols are NOT gases. Their inertia gives us a handle on them. Their inertia can confound...tubing to collector without wall losses0 25 50 75 100 0 2 4 6 8 10 Particle Size (m) S a m p l i n g E f f i c i e n c y , % Typical sampler ...efficiency data 10 Aerosol Sampler Technology Challenges Description Goals • High efficiency inlets for 1-10 micron particles and wind speeds

  10. Fluorescent biological aerosol particles measured with the Waveband Integrated Bioaerosol Sensor WIBS-4: laboratory tests combined with a one year field study

    NASA Astrophysics Data System (ADS)

    Toprak, E.; Schnaiter, M.

    2013-01-01

    In this paper bioaerosol measurements conducted with the Waveband Integrated Bioaerosol Sensor mark 4 (WIBS-4) are presented. The measurements comprise aerosol chamber characterization experiments and a one-year ambient measurement period at a semi-rural site in South Western Germany. This study aims to investigate the sensitivity of WIBS-4 to biological and non-biological aerosols and detection of biological particles in the ambient aerosol. Several types of biological and non-biological aerosol samples, including fungal spores, bacteria, mineral dust, ammonium sulphate, combustion soot, and fluorescent polystyrene spheres, were analyzed by WIBS-4 in the laboratory. The results confirm the sensitivity of the ultraviolet light-induced fluorescence (UV-LIF) method to biological fluorophores and show the good discrimination capabilities of the two excitation wavelengths/detection wavebands method applied in WIBS-4. However, a weak cross-sensitivity to non-biological fluorescent interferers remains and is discussed in this paper. All the laboratory studies have been undertaken in order to prepare WIBS-4 for ambient aerosol measurements. According to the one-year ambient aerosol study, number concentration of fluorescent biological aerosol particles (FBAP) show strong seasonal and diurnal variability. The highest number concentration of FBAP was measured during the summer term and decreased towards the winter period when colder and drier conditions prevail. Diurnal FBAP concentrations start to increase after sunset and reach maximum values during the late night and early morning hours. On the other hand, the total aerosol number concentration was almost always higher during daytime than during nighttime and a sharp decrease after sunset was observed. There was no correlation observed between the FBAP concentration and the meteorological parameters temperature, precipitation, wind direction and wind speed. However, a clear correlation was identified between the FBAP

  11. Global Atmospheric Aerosol Modeling

    NASA Technical Reports Server (NTRS)

    Hendricks, Johannes; Aquila, Valentina; Righi, Mattia

    2012-01-01

    Global aerosol models are used to study the distribution and properties of atmospheric aerosol particles as well as their effects on clouds, atmospheric chemistry, radiation, and climate. The present article provides an overview of the basic concepts of global atmospheric aerosol modeling and shows some examples from a global aerosol simulation. Particular emphasis is placed on the simulation of aerosol particles and their effects within global climate models.

  12. Challenges in defining a radiologic and hydrologic source term for underground nuclear test centers, Nevada Test Site, Nye County, Nevada

    SciTech Connect

    Smith, D.K.

    1995-06-01

    The compilation of a radionuclide inventory for long-lived radioactive contaminants residual from nuclear testing provides a partial measure of the radiologic source term at the Nevada Test Site. The radiologic source term also includes potentially mobile short-lived radionuclides excluded from the inventory. The radiologic source term for tritium is known with accuracy and is equivalent to the hydrologic source term within the saturated zone. Definition of the total hydrologic source term for fission and activation products that have high activities for decades following underground testing involves knowledge and assumptions which are presently unavailable. Systematic investigation of the behavior of fission products, activation products and actinides under saturated or Partially saturated conditions is imperative to define a representative total hydrologic source term. This is particularly important given the heterogeneous distribution of radionuclides within testing centers. Data quality objectives which emphasize a combination of measurements and credible estimates of the hydrologic source term are a priority for near-field investigations at the Nevada Test Site.

  13. Electronic cigarette solutions and resultant aerosol profiles.

    PubMed

    Herrington, Jason S; Myers, Colton

    2015-10-30

    Electronic cigarettes (e-cigarettes) are growing in popularity exponentially. Despite their ever-growing acceptance, their aerosol has not been fully characterized. The current study focused on evaluating e-cigarette solutions and their resultant aerosol for potential differences. A simple sampling device was developed to draw e-cigarette aerosol into a multi-sorbent thermal desorption (TD) tube, which was then thermally extracted and analyzed via a gas chromatography (GC) mass spectrometry (GC-MS) method. This novel application provided detectable levels of over one hundred fifteen volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) from a single 40mL puff. The aerosol profiles from four commercially available e-cigarettes were compared to their respective solution profiles with the same GC-MS method. Solution profiles produced upwards of sixty four unidentified and identified (some only tentatively) constituents and aerosol profiles produced upwards of eighty two compounds. Results demonstrated distinct analyte profiles between liquid and aerosol samples. Most notably, formaldehyde, acetaldehyde, acrolein, and siloxanes were found in the aerosol profiles; however, these compounds were never present in the solutions. These results implicate the aerosolization process in the formation of compounds not found in solutions; have potential implications for human health; and stress the need for an emphasis on electronic cigarette aerosol testing.

  14. A System to Create Stable Nanoparticle Aerosols from Nanopowders

    PubMed Central

    Ding, Yaobo; Riediker, Michael

    2016-01-01

    Nanoparticle aerosols released from nanopowders in workplaces are associated with human exposure and health risks. We developed a novel system, requiring minimal amounts of test materials (min. 200 mg), for studying powder aerosolization behavior and aerosol properties. The aerosolization procedure follows the concept of the fluidized-bed process, but occurs in the modified volume of a V-shaped aerosol generator. The airborne particle number concentration is adjustable by controlling the air flow rate. The system supplied stable aerosol generation rates and particle size distributions over long periods (0.5-2 hr and possibly longer), which are important, for example, to study aerosol behavior, but also for toxicological studies. Strict adherence to the operating procedures during the aerosolization experiments ensures the generation of reproducible test results. The critical steps in the standard protocol are the preparation of the material and setup, and the aerosolization operations themselves. The system can be used for experiments requiring stable aerosol concentrations and may also be an alternative method for testing dustiness. The controlled aerosolization made possible with this setup occurs using energy inputs (may be characterized by aerosolization air velocity) that are within the ranges commonly found in occupational environments where nanomaterial powders are handled. This setup and its operating protocol are thus helpful for human exposure and risk assessment. PMID:27501179

  15. A new test for evaluating Eighth Amendment challenges to lethal injections.

    PubMed

    2007-03-01

    An explosion of Eighth Amendment challenges to lethal injection protocols has struck the federal courts. The Supreme Court's recent decision in Hill v. McDonough,1 which empowered prisoners to bring challenges to lethal injection procedures under 42 U.S.C. para. 1983, has facilitated a flood of new lethal injection cases. In response, several courts have ordered states to alter their protocols, spurring other capital inmates to litigate such challenges. Distressingly, the courts evaluating these claims have almost no law to guide them. The last Supreme Court decision applying the Eighth Amendment to a method of execution was written in 1947; that case, Louisiana ex rel. Francis v. Resweber,2 occurred before the Eighth Amendment was applied to the states and resulted in a 4-1-4 split. Although lower courts have heard numerous challenges to execution methods, few have analyzed the constitutional validity of a method of execution in detail. Making matters worse, courts that find Eighth Amendment violations must craft equitable remedies that often amount to entirely new execution protocols. No clear precedent exists to guide courts in formulating such remedies. This Note proposes a legal standard for the administration of Eighth Amendment method-of-execution claims, focusing on lethal injection cases. Part I describes lethal injection procedures and summarizes recent litigation. Part II discusses the difficulty of evaluating lethal injection claims, analyzing both general difficulties in interpreting the Eighth Amendment and specific difficulties associated with lethal injection cases. Part III proposes a standard for addressing method-of-execution claims that attempts to balance a prisoner's interest in a painless execution with a state's interest in conducting executions efficiently. Part IV discusses remedies for unconstitutional procedures. Part V concludes.

  16. Assaying embryotoxicity in the test tube: current limitations of the embryonic stem cell test (EST) challenging its applicability domain.

    PubMed

    Riebeling, Christian; Hayess, Katrin; Peters, Annelieke K; Steemans, Margino; Spielmann, Horst; Luch, Andreas; Seiler, Andrea E M

    2012-05-01

    Testing for embryotoxicity in vitro is an attractive alternative to animal experimentation. The embryonic stem cell test (EST) is such a method, and it has been formally validated by the European Centre for the Validation of Alternative Methods. A number of recent studies have underscored the potential of this method. However, the EST performed well below the 78% accuracy expected from the validation study using a new set of chemicals and pharmaceutical compounds, and also of toxicity criteria, tested to enlarge the database of the validated EST as part of the Work Package III of the ReProTect Project funded within the 6th Framework Programme of the European Union. To assess the performance and applicability domain of the EST we present a detailed review of the substances and their effects in the EST being nitrofen, ochratoxin A, D-penicillamine, methylazoxymethanol, lovastatin, papaverine, warfarin, β-aminopropionitrile, dinoseb, furosemide, doxylamine, pravastatin, and metoclopramide. By delineation of the molecular mechanisms of the substances we identify six categories of reasons for misclassifications. Some of these limitations might also affect other in vitro methods assessing embryotoxicity. Substances that fall into these categories need to be included in future validation sets and in validation guidelines for embryotoxicity testing. Most importantly, we suggest conceivable improvements and additions to the EST which will resolve most of the limitations.

  17. Aerosol gels

    NASA Technical Reports Server (NTRS)

    Sorensen, Christopher M. (Inventor); Chakrabarti, Amitabha (Inventor); Dhaubhadel, Rajan (Inventor); Gerving, Corey (Inventor)

    2010-01-01

    An improved process for the production of ultralow density, high specific surface area gel products is provided which comprises providing, in an enclosed chamber, a mixture made up of small particles of material suspended in gas; the particles are then caused to aggregate in the chamber to form ramified fractal aggregate gels. The particles should have a radius (a) of up to about 50 nm and the aerosol should have a volume fraction (f.sub.v) of at least 10.sup.-4. In preferred practice, the mixture is created by a spark-induced explosion of a precursor material (e.g., a hydrocarbon) and oxygen within the chamber. New compositions of matter are disclosed having densities below 3.0 mg/cc.

  18. Public health genomics and genetic test evaluation: the challenge of conducting behavioural research on the utility of lifestyle-genetic tests.

    PubMed

    Sanderson, Saskia C; Wardle, Jane; Humphries, Steve E

    2008-01-01

    Human genetics research is increasingly concerned with multifactorial conditions such as diabetes and heart disease, which are influenced not only by genetic but also lifestyle factors such as diet and smoking. Although the results of 'lifestyle-genetic' tests using this information could conceivably motivate lifestyle changes in the future, companies are already selling such tests and related lifestyle advice commercially. Some academics and lobby groups have condemned the companies for selling these tests in advance of scientific support. Others are concerned that the tests may not motivate lifestyle improvements, instead causing distress in people receiving adverse test results and complacency in those receiving reassuring results. There is currently no regulatory oversight of genetic test utility, despite consensus in the Public Health Genomics community that clinical utility (including psychological and behavioural impact) of all emerging genetic tests should be evaluated before being introduced for individual use. Clearly, empirical data in this area is much needed, to inform understanding of the potential utility of these tests, and of whether stricter regulation of commercial exploitation is needed. In this article, we review the current situation regarding lifestyle-genetic tests, and discuss the challenges inherent in conducting this kind of behavioural research in the genomics era.

  19. Generation and characterization of biological aerosols for laser measurements

    SciTech Connect

    Cheng, Yung-Sung; Barr, E.B.

    1995-12-01

    Concerns for proliferation of biological weapons including bacteria, fungi, and viruses have prompted research and development on methods for the rapid detection of biological aerosols in the field. Real-time instruments that can distinguish biological aerosols from background dust would be especially useful. Sandia National Laboratories (SNL) is developing a laser-based, real-time instrument for rapid detection of biological aerosols, and ITRI is working with SNL scientists and engineers to evaluate this technology for a wide range of biological aerosols. This paper describes methods being used to generate the characterize the biological aerosols for these tests. In summary, a biosafe system has been developed for generating and characterizing biological aerosols and using those aerosols to test the SNL laser-based real-time instrument. Such tests are essential in studying methods for rapid detection of airborne biological materials.

  20. Challenging the Accuracy of a Single-test Lactate Threshold Protocol in Collegiate Rowers.

    PubMed

    Soma, Erica A; Lockard, Michael M; Stavrianeas, Stasinos

    Elite rowers use lactate threshold (LT) estimates as a basis for training intensity in order to achieve the greatest training volume. For convenience, LT is usually determined in a maximal LT/VO2max test. This simultaneous test is problematic because it requires a large power increment, which may not give the most accurate LT.

  1. Multidimensional Adaptive Testing in Educational and Psychological Measurement: Current State and Future Challenges

    ERIC Educational Resources Information Center

    Frey, Andreas; Seitz, Nicki-Nils

    2009-01-01

    The paper gives an overview of multidimensional adaptive testing (MAT) and evaluates its applicability in educational and psychological testing. The approach of Segall (1996) is described as a general framework for MAT. The main advantage of MAT is its capability to increase measurement efficiency. In simulation studies conceptualizing situations…

  2. "It Is Not Easy": Challenges for Provider-Initiated HIV Testing and Counseling in Flanders, Belgium

    ERIC Educational Resources Information Center

    Manirankunda, Lazare; Loos, Jasna; Debackaere, Pieterjan; Nostlinger, Christiana

    2012-01-01

    This study identified physicians' HIV testing practices and their barriers toward implementing provider-initiated HIV testing and counseling (PITC) for Sub-Saharan African migrants (SAM) in Flanders, Belgium. In-depth interviews were conducted on a purposive sample of 20 physicians (ten GPs and ten internists). GPs performed mainly…

  3. Aerosol typing - key information from aerosol studies

    NASA Astrophysics Data System (ADS)

    Mona, Lucia; Kahn, Ralph; Papagiannopoulos, Nikolaos; Holzer-Popp, Thomas; Pappalardo, Gelsomina

    2016-04-01

    Aerosol typing is a key source of aerosol information from ground-based and satellite-borne instruments. Depending on the specific measurement technique, aerosol typing can be used as input for retrievals or represents an output for other applications. Typically aerosol retrievals require some a priori or external aerosol type information. The accuracy of the derived aerosol products strongly depends on the reliability of these assumptions. Different sensors can make use of different aerosol type inputs. A critical review and harmonization of these procedures could significantly reduce related uncertainties. On the other hand, satellite measurements in recent years are providing valuable information about the global distribution of aerosol types, showing for example the main source regions and typical transport paths. Climatological studies of aerosol load at global and regional scales often rely on inferred aerosol type. There is still a high degree of inhomogeneity among satellite aerosol typing schemes, which makes the use different sensor datasets in a consistent way difficult. Knowledge of the 4d aerosol type distribution at these scales is essential for understanding the impact of different aerosol sources on climate, precipitation and air quality. All this information is needed for planning upcoming aerosol emissions policies. The exchange of expertise and the communication among satellite and ground-based measurement communities is fundamental for improving long-term dataset consistency, and for reducing aerosol type distribution uncertainties. Aerosol typing has been recognized as one of its high-priority activities of the AEROSAT (International Satellite Aerosol Science Network, http://aero-sat.org/) initiative. In the AEROSAT framework, a first critical review of aerosol typing procedures has been carried out. The review underlines the high heterogeneity in many aspects: approach, nomenclature, assumed number of components and parameters used for the

  4. Testing the Equivalence Principle in space with MICROSCOPE: the data analysis challenge

    NASA Astrophysics Data System (ADS)

    Bergé, Joel; Baghi, Quentin; Pires, Sandrine

    2014-05-01

    Theories beyond the Standard Model and General Relativity predict a violation of the Weak Equivalence Principle (WEP) just below the current best experimental upper limits. MICROSCOPE (Micro-Satellite à traînée Compensée pour l'Observation du Principe d'Equivalence) will allow us to lower them by two orders of magnitude, and maybe to detect a WEP violation. However, analyzing the MICROSCOPE data will be challenging, mostly because of missing data and a colored noise burrying the signal of interest. In this communication, we apply an inpainting technique to simulated MICROSCOPE data and show that inpainting will help detect a WEP violation signal.

  5. Fluorescent biological aerosol particles (FBAPs) measured with the Waveband Integrated Bioaerosol Sensor WIBS-4: laboratory tests combined with a one year field study

    NASA Astrophysics Data System (ADS)

    Toprak, E.; Schnaiter, M.

    2012-07-01

    In this paper bioaerosol measurements conducted with the Waveband Integrated Bioaerosol Sensor mark 4 (WIBS-4) are presented. The measurements comprise aerosol chamber characterization experiments and a one-year ambient measurement period at a semi-rural site in South Western Germany. This study aims to investigate the sensitivity of WIBS-4 to biological and non-biological aerosols, performance of WIBS-4 for discrimination of several types of aerosols, and the detection and identification of biological particles in the ambient aerosol. Several types of biological and non-biological aerosol samples including spores, bacteria, pollen, mineral dust, ammonium sulphate, combustion soot, and fluorescent polystyrene spheres were analysed by WIBS-4 in the laboratory. The results confirm the sensitivity of the Ultra Violet Light Induced Fluorescence (UV-LIF) method to biological fluorophores and show the good discrimination capabilities of the two wavelengths excitation/two wavebands detection method applied in WIBS-4. However, a weak cross-sensitivity to non-biological fluorescent interferers remains and is discussed in this paper. All the laboratory studies have been undertaken in order to prepare WIBS-4 for ambient aerosol measurements. According to the one year ambient aerosol study, number concentration of fluorescent biological aerosol particles (FBAP) show strong seasonal and diurnal variability. The highest number concentration of FBAP was measured during the summer term and it decreases towards the winter period when colder and drier conditions are prevailing. Diurnal FBAP concentrations start to increase after sunset and reach maximum values during the late night and early morning hours. On the other hand the total aerosol number concentration was always higher during day time than during night time and a sharp decrease after sunset was observed. There was no correlation observed between the FBAP concentration and the meteorological parameters temperature

  6. Aerosol Use in the Pulmonary Function Lab.

    PubMed

    Ruppel, Gregg L

    2015-06-01

    Aerosolized medications are frequently used in the pulmonary function laboratory. The 2 most common implementations are bronchodilators and bronchial challenge agents. Bronchodilator administration is not well standardized, largely because of the various methods of delivery available for clinical practice. Metered-dose inhalers used with spacer devices are the most common route for bronchodilator administration, but many laboratories use small-volume nebulizers. Interpretation of pre- and post-bronchodilator studies is confounded by the definitions of airway obstruction and bronchodilator responsiveness. Protocols for administering bronchial challenge aerosols (methacholine, mannitol, hypertonic saline) are well defined but are susceptible to some of the same problems that limit comparison of bronchodilator techniques. Bronchial challenges with inhaled aerosols are influenced not only by the delivery device but by the patient's breathing pattern, particularly in protocols that include deep inspiratory efforts.

  7. Generation of a monodispersed aerosol

    NASA Technical Reports Server (NTRS)

    Schenck, H.; Mikasa, M.; Devicariis, R.

    1974-01-01

    The identity and laboratory test methods for the generation of a monodispersed aerosol are reported on, and are subjected to the following constraints and parameters; (1) size distribution; (2) specific gravity; (3) scattering properties; (4) costs; (5) production. The procedure called for the collection of information from the literature, commercial available products, and experts working in the field. The following topics were investigated: (1) aerosols; (2) air pollution -- analysis; (3) atomizers; (4) dispersion; (5) particles -- optics, size analysis; (6) smoke -- generators, density measurements; (7) sprays; (8) wind tunnels -- visualization.

  8. A Novel Hypoxia Challenge Test Demonstrates Cardiovascular and Pulmonary Susceptibility to Acrolein Gas in Hypertensive Rats.

    EPA Science Inventory

    High levels of air pollution increase the risk of cardiovascular morbidity and mortality, especially in susceptible populations including those with hypertension. Stress tests are useful for manifesting latent effects of exposure, particularly at low concentrations, often when no...

  9. Particle-size dependence of immersion freezing: Investigation of INUIT test aerosol particles with freely suspended water drops.

    NASA Astrophysics Data System (ADS)

    Diehl, Karoline; Debertshäuser, Michael; Eppers, Oliver; Jantsch, Evelyn; Mitra, Subir K.

    2014-05-01

    One goal of the research group INUIT (Ice Nuclei research UnIT) is to investigate the efficiencies of several test ice nuclei under comparable conditions but with different experimental techniques. In the present studies, two methods are used: the Mainz vertical wind tunnel and an acoustic levitator placed inside a cold chamber. In both cases drops are freely levitated, either at their terminal velocity in the wind tunnel updraft or around the nodes of a standing ultrasonic wave in the acoustic levitator. Thus, heat transfer conditions are well approximated, and wall contact effects on freezing as well as electrical charges of the drops are avoided. Drop radii are 370 μm and 1 mm, respectively. In the wind tunnel, drops are investigated at constant temperatures within a certain time period and the onset of freezing is observed directly. In the acoustic levitator, the drop temperature decreases during the experiments and is measured by an in-situ calibrated Infrared thermometer. The onset of freezing is indicated by a rapid rise of the drop surface temperature because of the release of latent heat. Investigated test ice nuclei are Snomax® as a proxy of biological particles and illite NX as well as K-feldspar as represents of mineral dust. The particle concentrations are 1 × 10-12 to 3 × 10-6 g Snomax® per drop and 5 × 10-9 to 5 × 10-5 g mineral dust per drop. Freezing temperatures are between -2 and -18° C in case of Snomax® and between -14 and -26° C in case of mineral dust. The lower the particle masses per drop the lower are the freezing temperatures. For similar particle concentrations in the drops, the median freezing temperatures determined by the two techniques agree well within the measurement errors. With the knowledge of the specific particle surface area of the mineral dusts, the results are interpreted also in terms of particle surface area per drop. Results from the wind tunnel experiments which are performed at constant temperatures indicate

  10. Recombinant Mal d 1 facilitates sublingual challenge tests of birch pollen-allergic patients with apple allergy.

    PubMed

    Kinaciyan, T; Nagl, B; Faustmann, S; Kopp, S; Wolkersdorfer, M; Bohle, B

    2016-02-01

    It is still unclear whether allergen-specific immunotherapy (AIT) with birch pollen improves birch pollen-related food allergy. One reason for this may be the lack of standardized tests to assess clinical reactions to birch pollen-related foods, for example apple. We tested the applicability of recombinant (r) Mal d 1, the Bet v 1-homolog in apple, for oral challenge tests. Increasing concentrations of rMal d 1 in 0.9% NaCl were sublingually administered to 72 birch pollen-allergic patients with apple allergy. The dose of 1.6 μg induced oral allergy syndromes in 26.4%, 3.2 μg in 15.3%, 6.3 μg in 27.8%, 12.5 μg in 8.3%, 25 μg in 11.1%, and 50 μg in 4.2% of the patients. No severe reactions occurred. None of the patients reacted to 0.9% NaCl alone. Sublingual administration of 50 μg of rMal d 1 induced no reactions in three nonallergic individuals. Our approach allows straight forward, dose-defined sublingual challenge tests in a high number of birch pollen-allergic patients that inter alia can be applied to evaluate the therapeutic efficacy of birch pollen AIT on birch pollen-related food allergy.

  11. Challenges in the clinical utility of the serum test for HER2 ECD

    PubMed Central

    Lam, Lian; McAndrew, Nicholas; Yee, Marla; Fu, Ting; Tchou, Julia C.; Zhang, Hongtao

    2012-01-01

    Approximately 15–30% of breast cancers over-express the HER2/neu receptor. Historically, over-expression of HER2/neu has been identified using IHC or FISH, both of which are invasive approaches requiring tissue samples. Recent evidence has shown that some tumors identified as “negative” using these methods can respond to HER2/neu targeted therapy. Shedding of the extracellular domain (ECD) of the receptor into the circulation has led to the development of serum test of HER2 ECD as an additional approach to probe HER2/neu overexpression. The serum test will be able to monitor the dynamic changes of HER2 status over the course of disease progression. Some studies further suggest that the serum HER2 ECD level and its change may serve as a biomarker to reflect patients’ response to therapy. Yet more than 10 years after the first serum HER2 ECD test was approved by the FDA, serum HER2 testing has yet to be widely used in clinical practice. In this article we will review the progress of the serum HER2 ECD test and discuss some obstacles impeding its incorporation into broad clinical practice. We will also discuss recent improvements in the sensitivity and specificity of the assay that offer some hope for the future of serum HER2 test. PMID:22521738

  12. Stratospheric Aerosol--Observations, Processes, and Impact on Climate

    NASA Technical Reports Server (NTRS)

    Kresmer, Stefanie; Thomason, Larry W.; von Hobe, Marc; Hermann, Markus; Deshler, Terry; Timmreck, Claudia; Toohey, Matthew; Stenke, Andrea; Schwarz, Joshua P.; Weigel, Ralf; Fueglistaler, Stephan; Prata, Fred J.; Vernier, Jean-Paul; Schlager, Hans; Barnes, John E.; Antuna-Marrero, Juan-Carlos; Fairlie, Duncan; Palm, Mathias; Mahieu, Emmanuel; Notholt, Justus; Rex, Markus; Bingen, Christine; Vanhellemont, Filip; Bourassa, Adam; Plane, John M. C.; Klocke, Daniel; Carn, Simon A.; Clarisse, Lieven; Trickl, Thomas; Neeley, Ryan; James, Alexander D.; Rieger, Landon; Wilson, James C.; Meland, Brian

    2016-01-01

    Interest in stratospheric aerosol and its role in climate have increased over the last decade due to the observed increase in stratospheric aerosol since 2000 and the potential for changes in the sulfur cycle induced by climate change. This review provides an overview about the advances in stratospheric aerosol research since the last comprehensive assessment of stratospheric aerosol was published in 2006. A crucial development since 2006 is the substantial improvement in the agreement between in situ and space-based inferences of stratospheric aerosol properties during volcanically quiescent periods. Furthermore, new measurement systems and techniques, both in situ and space based, have been developed for measuring physical aerosol properties with greater accuracy and for characterizing aerosol composition. However, these changes induce challenges to constructing a long-term stratospheric aerosol climatology. Currently, changes in stratospheric aerosol levels less than 20% cannot be confidently quantified. The volcanic signals tend to mask any nonvolcanically driven change, making them difficult to understand. While the role of carbonyl sulfide as a substantial and relatively constant source of stratospheric sulfur has been confirmed by new observations and model simulations, large uncertainties remain with respect to the contribution from anthropogenic sulfur dioxide emissions. New evidence has been provided that stratospheric aerosol can also contain small amounts of nonsulfatematter such as black carbon and organics. Chemistry-climate models have substantially increased in quantity and sophistication. In many models the implementation of stratospheric aerosol processes is coupled to radiation and/or stratospheric chemistry modules to account for relevant feedback processes.

  13. Integration and Testing Challenges of Small Satellite Missions: Experiences from the Space Technology 5 Project

    NASA Technical Reports Server (NTRS)

    Sauerwein, Timothy A.; Gostomski, Tom

    2007-01-01

    The Space Technology 5(ST5) payload was successfully carried into orbit on an OSC Pegasus XL launch vehicle, which was carried aloft and dropped from the OSC Lockheed L-1011 from Vandenberg Air Force Base March 22,2006, at 9:03 am Eastern time, 6:03 am Pacific time. In order to reach the completion of the development and successful launch of ST 5, the systems integration and test(I&T) team determined that a different approach was required to meet the project requirements rather than the standard I&T approach used for single, room-sized satellites. The ST5 payload, part of NASA's New Millennium Program headquartered at JPL, consisted of three micro satellites (approximately 30 kg each) and the Pegasus Support Structure (PSS), the system that connected the spacecrafts to the launch vehicle and deployed the spacecrafts into orbit from the Pegasus XL launch vehicle. ST5 was a technology demonstration payload, intended to test six (6) new technologies for potential use for future space flights along with demonstrating the ability of small satellites to perform quality science. The main technology was a science grade magnetometer designed to take measurements of the earth's magnetic field. The three spacecraft were designed, integrated, and tested at NASA Goddard Space Flight Center with integration and environmental testing occurring in the Bldg. 7-1 0-15-29. The three spacecraft were integrated and tested by the same I&T team. The I&T Manager determined that there was insufficient time in the schedule to perform the three I&T spacecraft activities in series used standard approaches. The solution was for spacecraft #1 to undergo integration and test first, followed by spacecraft #2 and #3 simultaneously. This simultaneous integration was successful for several reasons. Each spacecraft had a Lead Test Conductor who planned and coordinated their spacecraft through its integration and test activities. One team of engineers and technicians executed the integration of all

  14. Retrieving Aerosol in a Cloudy Environment: Aerosol Availability as a Function of Spatial and Temporal Resolution

    NASA Technical Reports Server (NTRS)

    Remer, Lorraine A.; Mattoo, Shana; Levy, Robert C.; Heidinger, Andrew; Pierce, R. Bradley; Chin, Mian

    2011-01-01

    The challenge of using satellite observations to retrieve aerosol properties in a cloudy environment is to prevent contamination of the aerosol signal from clouds, while maintaining sufficient aerosol product yield to satisfy specific applications. We investigate aerosol retrieval availability at different instrument pixel resolutions, using the standard MODIS aerosol cloud mask applied to MODIS data and a new GOES-R cloud mask applied to GOES data for a domain covering North America and surrounding oceans. Aerosol availability is not the same as the cloud free fraction and takes into account the technqiues used in the MODIS algorithm to avoid clouds, reduce noise and maintain sufficient numbers of aerosol retrievals. The inherent spatial resolution of each instrument, 0.5x0.5 km for MODIS and 1x1 km for GOES, is systematically degraded to 1x1 km, 2x2 km, 4x4 km and 8x8 km resolutions and then analyzed as to how that degradation would affect the availability of an aerosol retrieval, assuming an aerosol product resolution at 8x8 km. The results show that as pixel size increases, availability decreases until at 8x8 km 70% to 85% of the retrievals available at 0.5 km have been lost. The diurnal pattern of aerosol retrieval availability examined for one day in the summer suggests that coarse resolution sensors (i.e., 4x4 km or 8x8 km) may be able to retrieve aerosol early in the morning that would otherwise be missed at the time of current polar orbiting satellites, but not the diurnal aerosol properties due to cloud cover developed during the day. In contrast finer resolution sensors (i.e., 1x1 km or 2x2 km) have much better opportunity to retrieve aerosols in the partly cloudy scenes and better chance of returning the diurnal aerosol properties. Large differences in the results of the two cloud masks designed for MODIS aerosol and GOES cloud products strongly reinforce that cloud masks must be developed with specific purposes in mind and that a generic cloud mask

  15. Development of unmanned aerial vehicle (UAV) based high altitude balloon (HAB) platform for active aerosol sampling

    NASA Astrophysics Data System (ADS)

    Lateran, S.; Sedan, M. F.; Harithuddin, A. S. M.; Azrad, S.

    2016-10-01

    The knowledge on the abundance and diversity of the minute particles or aerosols in the earth's stratosphere is still in its infancy as aerosol sampling at high-altitude still possess a lot of challenges. Thus far, high-altitude aerosol sampling has been conducted mostly using manned flights, which requires enormous financial and logistical resources. There had been researches for the utilisation of high altitude balloon (HAB) for active and passive aerosol samplings within the stratosphere. However, the gathered samples in the payload were either brought down by controlling the balloon air pressure or were just dropped with a parachute to slow the descend speed in order to reduce the impact upon landing. In most cases, the drop location of the sample are unfavorable such as in the middle of the sea, dense foliage, etc. Hence a system that can actively sample aerosols at high-altitude and improve the delivery method in terms of quality and reliability using unmanned aerial vehicle (UAV) is designed and tested in this study.

  16. Direct Aerosol Radiative Forcing Based on Combined A-Train Observations: Towards All-sky Estimates and Attribution to Aerosol Type

    NASA Technical Reports Server (NTRS)

    Redemann, Jens; Shinozuka, Y.; Kacenelenbogen, M.; Russell, P.; Vaughan, M.; Ferrare, R.; Hostetler, C.; Rogers, R.; Burton, S.; Livingston, J.; Torres, O.; Remer, L.

    2014-01-01

    We describe a technique for combining CALIOP aerosol backscatter, MODIS spectral AOD (aerosol optical depth), and OMI AAOD (absorption aerosol optical depth) measurements for the purpose of estimating full spectral sets of aerosol radiative properties, and ultimately for calculating the 3-D distribution of direct aerosol radiative forcing. We present results using one year of data collected in 2007 and show comparisons of the aerosol radiative property estimates to collocated AERONET retrievals. Initial calculations of seasonal clear-sky aerosol radiative forcing based on our multi-sensor aerosol retrievals compare well with over-ocean and top of the atmosphere IPCC-2007 model-based results, and with more recent assessments in the "Climate Change Science Program Report: Atmospheric Aerosol Properties and Climate Impacts" (2009). We discuss some of the challenges that exist in extending our clear-sky results to all-sky conditions. On the basis of comparisons to suborbital measurements, we present some of the limitations of the MODIS and CALIOP retrievals in the presence of adjacent or underlying clouds. Strategies for meeting these challenges are discussed. We also discuss a methodology for using the multi-sensor aerosol retrievals for aerosol type classification based on advanced clustering techniques. The combination of research results permits conclusions regarding the attribution of aerosol radiative forcing to aerosol type.

  17. Biologics industry challenges for developing diagnostic tests for the National Veterinary Stockpile.

    PubMed

    Hardham, J M; Lamichhane, C M

    2013-01-01

    Veterinary diagnostic products generated ~$3 billion US dollars in global sales in 2010. This industry is poised to undergo tremendous changes in the next decade as technological advances move diagnostic products from the traditional laboratory-based and handheld immunologic assays towards highly technical, point of care devices with increased sensitivity, specificity, and complexity. Despite these opportunities for advancing diagnostic products, the industry continues to face numerous challenges in developing diagnostic products for emerging and foreign animal diseases. Because of the need to deliver a return on the investment, research and development dollars continue to be focused on infectious diseases that have a negative impact on current domestic herd health, production systems, or companion animal health. Overcoming the administrative, legal, fiscal, and technological barriers to provide veterinary diagnostic products for the National Veterinary Stockpile will reduce the threat of natural or intentional spread of foreign diseases and increase the security of the food supply in the US.

  18. Addressing the ethical challenges in genetic testing and sequencing of children.

    PubMed

    Clayton, Ellen Wright; McCullough, Laurence B; Biesecker, Leslie G; Joffe, Steven; Ross, Lainie Friedman; Wolf, Susan M

    2014-01-01

    American Academy of Pediatrics (AAP) and American College of Medical Genetics (ACMG) recently provided two recommendations about predictive genetic testing of children. The Clinical Sequencing Exploratory Research Consortium's Pediatrics Working Group compared these recommendations, focusing on operational and ethical issues specific to decision making for children. Content analysis of the statements addresses two issues: (1) how these recommendations characterize and analyze locus of decision making, as well as the risks and benefits of testing, and (2) whether the guidelines conflict or come to different but compatible conclusions because they consider different testing scenarios. These statements differ in ethically significant ways. AAP/ACMG analyzes risks and benefits using best interests of the child and recommends that, absent ameliorative interventions available during childhood, clinicians should generally decline to order testing. Parents authorize focused tests. ACMG analyzes risks and benefits using the interests of the child and other family members and recommends that sequencing results be examined for additional variants that can lead to ameliorative interventions, regardless of age, which laboratories should report to clinicians who should contextualize the results. Parents must accept additional analysis. The ethical arguments in these statements appear to be in tension with each other.

  19. Decoding laboratory test names: a major challenge to appropriate patient care.

    PubMed

    Passiment, Elissa; Meisel, James L; Fontanesi, John; Fritsma, George; Aleryani, Samir; Marques, Marisa

    2013-03-01

    Clinical laboratory tests have no value if clinicians cannot quickly order and obtain the results they need. We found that efforts to obtain even the most commonly ordered tests are often derailed by excessively complex nomenclature. Ordering the right laboratory tests is critical to diagnosis and treatment, but existing mechanisms for entering lab orders actively interfere with physicians' efforts to provide good clinical care. Rather than simplifying lab orders, the advent of computerized physician order entry (CPOE) systems-generally programmed by non-clinicians-has introduced new and vexing practical problems. Medical laboratories have filled their test menus, whether paper or electronic, with bewildering nomenclature and abbreviations, and have failed to appreciate the dangers of assigning perilously similar names to different tests. The efficient and efficacious patient care demanded by the quality care initiative requires progress beyond traditional solutions, such as convening naming conventions, to the development of innovative software with intelligent, real-time, clinically driven search functions that will allow these programs to help rather than hinder physicians.

  20. The challenge of implementing genetic tests with clinical utility while avoiding unsound applications.

    PubMed

    Cornel, Martina C; van El, Carla G; Borry, Pascal

    2014-01-01

    Genetics and genomics have developed fast in the last decade, but have not revolutionized medicine, as some had expected. While translation of research findings to public health applications is lagging behind, direct-to-consumer (DTC) offers of genetic testing have become available, both for monogenic and severe genetic disorders and for genetic variants possibly associated with common complex diseases (susceptibility variants). The European Society of Human Genetics is concerned about the way in which commercial companies are currently introducing genetic tests into the market outside of the scope of the traditional health-care system. There is a sort of a paradox between the lagging implementation in health care of the few genetic tests with proven clinical utility, on the one hand, and the speedy DTC offer of tests, with or without clinical utility. To translate research findings into appropriate clinical applications, assessment of the clinical validity and utility is needed. Many of the parameters needed in assessment frameworks are not available yet. Clinically relevant associations between genetic variants and disease risks have been established, e.g., in oncogenetics and cardiogenetics, and can be used to reflect on the possibilities and obstacles in using the new genetics in public health. In the absence of sufficient information on clinical validity and clinical utility, introduction of genetic tests in common complex disorders is often premature. Priority should be given to settings where clinical utility is proven or likely, to gain additional information concerning diagnosis, prognosis, and disease management. Monitoring and evaluation are essential.

  1. Improvement of MODIS aerosol retrievals near clouds

    NASA Astrophysics Data System (ADS)

    Wen, Guoyong; Marshak, Alexander; Levy, Robert C.; Remer, Lorraine A.; Loeb, Norman G.; Várnai, Tamás.; Cahalan, Robert F.

    2013-08-01

    retrieval of aerosol properties near clouds from reflected sunlight is challenging. Sunlight reflected from clouds can effectively enhance the reflectance in nearby clear regions. Ignoring cloud 3-D radiative effects can lead to large biases in aerosol retrievals, risking an incorrect interpretation of satellite observations on aerosol-cloud interaction. Earlier, we developed a simple model to compute the cloud-induced clear-sky radiance enhancement that is due to radiative interaction between boundary layer clouds and the molecular layer above. This paper focuses on the application and implementation of the correction algorithm. This is the first time that this method is being applied to a full Moderate Resolution Imaging Spectroradiometer (MODIS) granule. The process of the correction includes converting Clouds and the Earth's Radiant Energy System broadband flux to visible narrowband flux, computing the clear-sky radiance enhancement, and retrieving aerosol properties. We find that the correction leads to smaller values in aerosol optical depth (AOD), Ångström exponent, and the small mode aerosol fraction of the total AOD. It also makes the average aerosol particle size larger near clouds than far away from clouds, which is more realistic than the opposite behavior observed in operational retrievals. We discuss issues in the current correction method as well as our plans to validate the algorithm.

  2. Asian Aerosols: A Geophysical Fluid Dynamics Laboratory general circulation model sensitivity study of model response to aerosol optical depth and aerosol absorption

    NASA Astrophysics Data System (ADS)

    Randles, C. A.; Ramaswamy, V.

    2007-12-01

    Atmospheric absorption by black carbon (BC) aerosol heats the atmosphere while simultaneously cooling the surface and reducing latent and sensible heat fluxes from the land. Recent studies have shown that absorbing BC aerosol can have a large impact on regional climates, including modification of the hydrological cycle. However, significant uncertainties remain with regards to (a) the total amount of all aerosol species and (b) the amount of aerosol absorption. Here we present a GCM sensitivity study focusing on the influences due to total aerosol amount and aerosol absorption in the south and east Asian regions. Six experiments are conducted to test the equilibrium response of the GFDL AM2 GCM (under conditions of prescribed, observed sea surface temperatures) to (i) changes in aerosol absorption caused by changes in BC aerosol amount, and (ii) aerosol extinction optical depth increases corresponding to the year 1990 relative to a control case of 1950. In order to systematically explore the uncertainties in aerosol loading and absorption, the sensitivity experiments are classified into four regimes: low extinction optical depth, low absorption; low extinction optical depth, high absorption; high extinction optical depth, low absorption; and high extinction optical depth, high absorption. Changes in surface temperature and changes in the hydrological cycle are generally insignificant when lower aerosol extinction optical depths are considered. For higher extinction optical depths, the change in the modeled regional circulation relative to the control circulation over south and east Asia is affected by the amount of aerosol absorption and contrasts sharply to the regional circulation change associated with increasing only scattering aerosols. When increasing absorbing aerosols over the region, low-level convergence and increases in vertical velocity overcome the stabilizing effects of the absorbing aerosol and enhance the monsoonal circulation and precipitation rate

  3. Clinical uncertainties, health service challenges, and ethical complexities of HIV "test-and-treat": a systematic review.

    PubMed

    Kulkarni, Sonali P; Shah, Kavita R; Sarma, Karthik V; Mahajan, Anish P

    2013-06-01

    Despite the HIV "test-and-treat" strategy's promise, questions about its clinical rationale, operational feasibility, and ethical appropriateness have led to vigorous debate in the global HIV community. We performed a systematic review of the literature published between January 2009 and May 2012 using PubMed, SCOPUS, Global Health, Web of Science, BIOSIS, Cochrane CENTRAL, EBSCO Africa-Wide Information, and EBSCO CINAHL Plus databases to summarize clinical uncertainties, health service challenges, and ethical complexities that may affect the test-and-treat strategy's success. A thoughtful approach to research and implementation to address clinical and health service questions and meaningful community engagement regarding ethical complexities may bring us closer to safe, feasible, and effective test-and-treat implementation.

  4. Developing a standardized test procedure for hybrid vehicles: The challenge of the SAE HEV task force

    NASA Astrophysics Data System (ADS)

    Penney, Terry; Christensen, David; Poulos, Stephen

    1994-11-01

    In 1992, the Society of Automotive Engineers (SAE) established a task force to develop a procedure for measuring electric energy consumption, all-electric range, fuel economy, and exhaust emissions for hybrid vehicles; the procedure will be submitted to regulatory agencies as representing the automotive industry's recommendations. The draft procedure is currently being tested on hybrid vehicles. The University of Maryland's parallel hybrid was tested in September 1994, and the University of California-Davis' parallel hybrid and the University of Illinois' series hybrid will be tested in November 1994 and January 1995, respectively. The procedure is being modified to incorporate any lessons learned, and the task force hopes to recommend the final procedure to the SAE by mid 1995.

  5. Integration and Testing Challenges of Small, Multiple Satellite Missions: Experiences from the Space Technology 5 Project

    NASA Technical Reports Server (NTRS)

    Sauerwein, Timothy A.; Gostomski, Thomas

    2008-01-01

    The ST5 technology demonstration mission led by GSFC of NASA's New Millennium Program managed by JPL consisted of three micro satellites (approximately 30 kg each) deployed into orbit from the Pegasus XL launch vehicle. In order to meet the launch date schedule of ST5, a different approach was required rather than the standard I&T approach used for single, room-sized satellites. The three spacecraft were designed, integrated, and tested at NASA Goddard Space Flight Center. It was determined that there was insufficient time in the schedule to perform three spacecraft I&T activities in series using standard approaches. The solution was for spacecraft #1 to undergo integration and test first, followed by spacecraft #2 and #3 simultaneously. This simultaneous integration was successful for several reasons. Each spacecraft had a Lead Test Conductor who planned and coordinated their spacecraft through its integration and test activities. One team of engineers and technicians executed the integration of all three spacecraft, learning and gaining knowledge and efficiency as spacecraft #1 integration and testing progressed. They became acutely familiar with the hardware, operation and processes for I&T, thus had the experience and knowledge to safely execute I&T for spacecraft #2 and #3. The integration team was extremely versatile; each member could perform many different activities or work any spacecraft, when needed. ST5 was successfully integrated, tested and shipped to the launch site per the I&T schedule that was planned three years previously. The I&T campaign was completed with ST5's successful launch on March 22, 2006.

  6. Noninvasive prenatal testing for trisomy 21: challenges for implementation in Australia.

    PubMed

    Hui, Lisa; Hyett, Jon

    2013-10-01

    The term 'Non invasive prenatal testing' is used to describe the rapidly emerging molecular technologies related to cell free DNA assessment that are being applied to prenatal screening for Down syndrome and other chromosomal abnormalities. This technology is now available to Australian women through a number of off-shore laboratories. We review the basis of this method of testing, the literature describing the effectiveness of NIPT in screening for trisomy 21 and the potential methods by which this tool could be incorporated into current screening strategies.

  7. Successful Completion of the JWST OGSE2 Cryogenic Test at JSC Chamber-A While Managing Numerous Challenges

    NASA Technical Reports Server (NTRS)

    Park, Sang C.; Brinckerhoff, Pamela; Franck, Randy; Schweickart, Rusty; Thomson, Shaun; Burt, Bill; Ousley, Wes

    2016-01-01

    The James Webb Space Telescope (JWST) Optical Telescope Element (OTE) assembly is the largest optically stable infrared-optimized telescope currently being manufactured and assembled, and scheduled for launch in 2018. The JWST OTE, including the primary mirrors, secondary mirror, and the Aft Optics Subsystems (AOS) are designed to be passively cooled and operate at near 45 degrees Kelvin. Due to the size of its large sunshield in relation to existing test facilities, JWST cannot be optically or thermally tested as a complete observatory-level system at flight temperatures. As a result, the telescope portion along with its instrument complement will be tested as a single unit very late in the program, and on the program schedule critical path. To mitigate schedule risks, a set of 'pathfinder' cryogenic tests will be performed to reduce program risks by demonstrating the optical testing capabilities of the facility, characterizing telescope thermal performance, and allowing project personnel to learn valuable testing lessons off-line. This paper describes the 'pathfinder' cryogenic test program, focusing on the recently completed second test in the series called the Optical Ground Support Equipment 2 (OGSE2) test. The JWST OGSE2 was successfully completed within the allocated project schedule while faced with numerous conflicting thermal requirements during cool-down to the final cryogenic operational temperatures, and during warm-up after the cryo-stable optical tests. The challenges include developing a pre-test cool-down and warm-up profiles without a reliable method to predict the thermal behaviors in a rarified helium environment, and managing the test article hardware safety driven by the project Limits and Constraints (L&C's). Furthermore, OGSE2 test included the time critical Aft Optics Subsystem (AOS), a part of the flight Optical Telescope Element that would need to be placed back in the overall telescope assembly integrations. The OGSE2 test requirements

  8. Hospital washbasin water: risk of Legionella-contaminated aerosol inhalation.

    PubMed

    Cassier, P; Landelle, C; Reyrolle, M; Nicolle, M C; Slimani, S; Etienne, J; Vanhems, P; Jarraud, S

    2013-12-01

    The contamination of aerosols by washbasin water colonized by Legionella in a hospital was evaluated. Aerosol samples were collected by two impingement technologies. Legionella was never detected by culture in all the (aerosol) samples. However, 45% (18/40) of aerosol samples were positive for Legionella spp. by polymerase chain reaction, with measurable concentrations in 10% of samples (4/40). Moreover, immunoassay detected Legionella pneumophila serogroup 1 and L. anisa, and potentially viable bacteria were seen on viability testing. These data suggest that colonized hospital washbasins could represent risks of exposure to Legionella aerosol inhalation, especially by immunocompromised patients.

  9. Introduction and Overview of High Stakes Testing: New Challenges and Opportunities for School Psychology

    ERIC Educational Resources Information Center

    Shriberg, David; Kruger, Louis J.

    2007-01-01

    This overview article addresses the different meanings of high takes testing, which takes into consideration accountability at different levels, such as teacher, school, and state. In this regard, "high-stakes" may mean different things in different states or countries. We will advance an argument for why school psychologists should (a) be…

  10. The Introduction of Standardized External Testing in Ukraine: Challenges and Successes

    ERIC Educational Resources Information Center

    Kovalchuk, Serhiy; Koroliuk, Svitlana

    2012-01-01

    Standardized external testing (SET) began to be implemented in Ukraine in 2008 as an instrument for combating corruption in higher education and ensuring fair university admission. This article examines the conditions and processes that led to the introduction of SET, overviews its implementation over three years (2008-10), analyzes SET and…

  11. Recycled poly(ethylene terephthalate) for direct food contact applications: challenge test of an inline recycling process.

    PubMed

    Franz, R; Welle, F

    2002-05-01

    Of all the plastics used for packaging, due to its low diffusivity and chemical inertness, poly(ethylene terephthalate) (PET) is one of the favoured candidate plastics for closed-loop recycling for new packaging applications. In the work reported here, a PET-recycling process was investigated with respect to its cleaning efficiency and compliance of the PET recyclate with food law. The key technology of the investigated PET-recycling process to remove contaminants consists of a predecontamination-extruder combination. At the end of the recycling process, there is either a pelletizing system or downstream equipment to produce preforms or flat sheets. Therefore, the process has two process options, an inline production of PET preforms and a batch option producing PET pellets. In the case of possible misuse of PET bottles by the consumer, the inline process produces higher concentrations in the bottle wall of the recyclate containing preforms. Owing to the dilution of the PET output material by large amounts of uncontaminated PET, the batch option is the less critical process in terms of consumer protection. Regarding an appropriate testing procedure for the evaluation of a bottle-to-bottle recycling process, both process options have their own specific requirements with respect to the design of a challenge test. A novel challenge test approach to the inline mode of a recycling process is presented here.

  12. Simulations of Aerosol Microphysics in the NASA GEOS-5 Model

    NASA Technical Reports Server (NTRS)

    Colarco, Peter; Smith; Randles; daSilva

    2010-01-01

    Aerosol-cloud-chemistry interactions have potentially large but uncertain impacts on Earth's climate. One path to addressing these uncertainties is to construct models that incorporate various components of the Earth system and to test these models against data. To that end, we have previously incorporated the Goddard Chemistry, Aerosol, Radiation, and Transport (GOCART) module online in the NASA Goddard Earth Observing System model (GEOS-5). GEOS-5 provides a platform for Earth system modeling, incorporating atmospheric and ocean general circulation models, a land surface model, a data assimilation system, and treatments of atmospheric chemistry and hydrologic cycle. Including GOCART online in this framework has provided a path for interactive aerosol-climate studies; however, GOCART only tracks the mass of aerosols as external mixtures and does not include the detailed treatments of aerosol size distribution and composition (internal mixtures) needed for aerosol-cloud-chemistry-climate studies. To address that need we have incorporated the Community Aerosol and Radiation Model for Atmospheres (CARMA) online in GEOS-5. CARMA is a sectional aerosol-cloud microphysical model, capable of treating both aerosol size and composition explicitly be resolving the aerosol distribution into a variable number of size and composition groupings. Here we present first simulations of dust, sea salt, and smoke aerosols in GEOS-5 as treated by CARMA. These simulations are compared to available aerosol satellite, ground, and aircraft data and as well compared to the simulated distributions in our current GOCART based system.

  13. AEROSOL AND GAS MEASUREMENT

    EPA Science Inventory

    Measurements provide fundamental information for evaluating and managing the impact of aerosols on air quality. Specific measurements of aerosol concentration and their physical and chemical properties are required by different users to meet different user-community needs. Befo...

  14. Workshop Summary: International Cooperative for Aerosol Prediction Workshop On Aerosol Forecast Verification

    NASA Technical Reports Server (NTRS)

    Benedetti, Angela; Reid, Jeffrey S.; Colarco, Peter R.

    2011-01-01

    The purpose of this workshop was to reinforce the working partnership between centers who are actively involved in global aerosol forecasting, and to discuss issues related to forecast verification. Participants included representatives from operational centers with global aerosol forecasting requirements, a panel of experts on Numerical Weather Prediction and Air Quality forecast verification, data providers, and several observers from the research community. The presentations centered on a review of current NWP and AQ practices with subsequent discussion focused on the challenges in defining appropriate verification measures for the next generation of aerosol forecast systems.

  15. Assessment of the Interactions Among Tropospheric Aerosol Loading, Radiative Balance and Clouds Through Examination of Their Multi-decadal Trends

    EPA Science Inventory

    While aerosol radiative effects have been recognized as some of the largest sources of uncertainty among the forcers of climate change, the verification of the spatial and temporal variability of aerosol radiative forcing has remained challenging. Anthropogenic emissions of prima...

  16. Antiphospholipid antibody testing for the antiphospholipid syndrome: a comprehensive practical review including a synopsis of challenges and recent guidelines.

    PubMed

    Favaloro, Emmanuel J; Wong, Richard C W

    2014-10-01

    The antiphospholipid (antibody) syndrome (APS) is an autoimmune condition characterised by a wide range of clinical features, but primarily identified as thrombotic and/or obstetric related adverse events. APS is associated with the presence of antiphospholipid antibodies (aPL), including the so-called lupus anticoagulant (LA). These aPL are heterogeneous in nature, detected with varying sensitivity and specificity by a diverse range of laboratory tests. All these tests are unfortunately imperfect, suffer from poor assay reproducibility (inter-method and inter-laboratory) and a lack of standardisation and harmonisation. Clinicians and laboratory personnel may struggle to keep abreast of these factors, as well as the expanding range of available aPL tests, and consequent result interpretation. Therefore, APS remains a significant diagnostic challenge for many clinicians across a wide range of clinical specialities, due to these issues related to laboratory testing as well as the ever-expanding range of reported clinical manifestations. This review is primarily focussed on issues related to laboratory testing for APS in regards to the currently available assays, and summarises recent international consensus guidelines for aPL testing, both for the liquid phase functional LA assays and the solid phase assays (anticardiolipin and anti-beta-2-Glycoprotein-I).

  17. Standards for Radiation Effects Testing: Ensuring Scientific Rigor in the Face of Budget Realities and Modern Device Challenges

    NASA Technical Reports Server (NTRS)

    Lauenstein, J M.

    2015-01-01

    An overview is presented of the space radiation environment and its effects on electrical, electronic, and electromechanical parts. Relevant test standards and guidelines are listed. Test standards and guidelines are necessary to ensure best practices, minimize and bound systematic and random errors, and to ensure comparable results from different testers and vendors. Test standards are by their nature static but exist in a dynamic environment of advancing technology and radiation effects research. New technologies, failure mechanisms, and advancement in our understanding of known failure mechanisms drive the revision or development of test standards. Changes to standards must be weighed against their impact on cost and existing part qualifications. There must be consensus on new best practices. The complexity of some new technologies exceeds the scope of existing test standards and may require development of a guideline specific to the technology. Examples are given to illuminate the value and limitations of key radiation test standards as well as the challenges in keeping these standards up to date.

  18. Microbial challenge-testing of treatment processes for quantifying stormwater recycling risks and management.

    PubMed

    Davies, C M; Mitchell, V G; Petterson, S M; Taylor, G D; Lewis, J; Kaucner, C; Ashbolt, N J

    2008-01-01

    Pathogenic microorganisms have been identified as the main human health risks associated with the reuse of treated urban stormwater (runoff from paved and unpaved urban areas). As part of the Smart Water initiative (Victorian Government, Australia), a collaborative evaluation of three existing integrated stormwater recycling systems, and the risks involved in non-potable reuse of treated urban stormwater is being undertaken. Three stormwater recycling systems were selected at urban locations to provide a range of barriers including biofiltration, storage tanks, UV disinfection, a constructed wetland, and retention ponds. Recycled water from each of the systems is used for open space irrigation. In order to adequately undertake exposure assessments, it was necessary to quantify the efficacy of key barriers in each exposure pathway. Given that none of the selected treatment systems had previously been evaluated for their treatment efficiency, experimental work was carried out comprising dry and wet weather monitoring of each system (for a period of 12 months), as well as challenging the barriers with model microbes (for viruses, bacteria and parasitic protozoa) to provide input data for use in Quantitative Microbial Risk Assessment.

  19. Satellite assisted aerosol correlation in a sequestered CO2 leakage controlled site

    NASA Astrophysics Data System (ADS)

    Landulfo, Eduardo; da Silva Lopes, Fábio J.; Nakaema, Walter M.; de Medeiros, José A. G.; Moreira, Andrea

    2014-10-01

    Currently one of the main challenges in CO2 storage research is to grant the development, testing and validation of accurate and efficient Measuring, Monitoring and Verification (MMV) techniques to be deployed at the final storage site, targeting maximum storage efficiency at the minimal leakage risk levels. For such task a mimetic sequestration site has been deployed in Florianopolis, Brazil, in order to verify the performance of monitoring plataforms to detect and quantify leakages of ground injected CO2, namely a Cavity Ring Down System (CRDS) - Los Gatos Research - an Eddy Covariance System (Campbell Scientific and Irgason) and meteorological tower for wind, humidity, precipitation and temperature monitoring onsite. The measurement strategy for detecting CO2 leakages can be very challenging since environmental and phytogenic influence can be very severe and play a role on determining if the values measured are unambiguous or not. One external factor to be considered is the amount of incoming solar radiation which will be the driving force for the whole experimental setup and following this reasoning the amount of aerosols in the atmospheric column can be a determinant factor influencing the experimental results. Thus the investigation of measured fluxes CO2 and its concentration with the aforementioned experimental instruments and their correlation with the aerosol data should be taken into account by means of satellite borne systems dedicated to measure aerosol vertical distribution and its optical properties, in this study we have selected CALIPSO and MODIS instrumentation to help on deriving the aerosol properties and CO2 measurements.

  20. Testing Together Challenges the Relationship’: Consequences of HIV Testing as a Couple in a High HIV Prevalence Setting in Rural South Africa

    PubMed Central

    Tabana, Hanani; Doherty, Tanya; Rubenson, Birgitta; Jackson, Debra; Ekström, Anna Mia; Thorson, Anna

    2013-01-01

    Objective We conducted qualitative individual and combined interviews with couples to explore their experiences since the time of taking an HIV test and receiving the test result together, as part of a home-based HIV counselling and testing intervention. Methods This study was conducted in October 2011 in rural KwaZulu-Natal, South Africa, about 2 years after couples tested and received results together. Fourteen couples were purposively sampled: discordant, concordant negative and concordant positive couples. Findings Learning about each other’s status together challenged relationships of the couples in different ways depending on HIV status and gender. The mutual information confirmed suspected infidelity that had not been discussed before. Negative women in discordant partnerships remained with their positive partner due to social pressure and struggled to maintain their HIV negative status. Most of the couple relationships were characterized by silence and mistrust. Knowledge of sero-status also led to loss of sexual intimacy in some couples especially the discordant. For most men in concordant negative couples, knowledge of status was an awakening of the importance of fidelity and an opportunity for behaviour change, while for concordant positive and discordant couples, it was seen as proof of infidelity. Although positive HIV status was perceived as confirmation of infidelity, couples continued their relationship and offered some support for each other, living and managing life together. Sexual life in these couples was characterized by conflict and sometimes violence. In the concordant negative couples, trust was enhanced and behaviour change was promised. Conclusions Findings suggest that testing together as couples challenged relationships in both negative and positive ways. Further, knowledge of HIV status indicated potential to influence behaviour change especially among concordant negatives. In the discordant and concordant positive couples

  1. Chloe’s Law: A Powerful Legislative Movement Challenging a Core Ethical Norm of Genetic Testing

    PubMed Central

    Caplan, Arthur L.

    2015-01-01

    Since the early 1970s, the ethical norm governing counselors involved in testing and screening for genetic conditions related to reproduction has been strict neutrality. Counseling about reproductive genetics was to be patient centered but nondirective. Many advocates for people with Down syndrome believe that high abortion rates following a diagnosis of this condition show an unfounded bias against those with Down syndrome. These advocates have succeeded in enacting federal and state legislation that requires women who receive a prenatal diagnosis of Down syndrome to receive positive information about the condition, thereby ending the nominal goal of value-neutral counseling and setting the stage for further normative shifts in clinical reproductive genetics as counseling expands because of cell-free testing. PMID:26247743

  2. Experimental aerosolized guinea pig-adapted Zaire ebolavirus (variant: Mayinga) causes lethal pneumonia in guinea pigs.

    PubMed

    Twenhafel, N A; Shaia, C I; Bunton, T E; Shamblin, J D; Wollen, S E; Pitt, L M; Sizemore, D R; Ogg, M M; Johnston, S C

    2015-01-01

    Eight guinea pigs were aerosolized with guinea pig-adapted Zaire ebolavirus (variant: Mayinga) and developed lethal interstitial pneumonia that was distinct from lesions described in guinea pigs challenged subcutaneously, nonhuman primates challenged by the aerosol route, and natural infection in humans. Guinea pigs succumbed with significant pathologic changes primarily restricted to the lungs. Intracytoplasmic inclusion bodies were observed in many alveolar macrophages. Perivasculitis was noted within the lungs. These changes are unlike those of documented subcutaneously challenged guinea pigs and aerosolized filoviral infections in nonhuman primates and human cases. Similar to findings in subcutaneously challenged guinea pigs, there were only mild lesions in the liver and spleen. To our knowledge, this is the first report of aerosol challenge of guinea pigs with guinea pig-adapted Zaire ebolavirus (variant: Mayinga). Before choosing this model for use in aerosolized ebolavirus studies, scientists and pathologists should be aware that aerosolized guinea pig-adapted Zaire ebolavirus (variant: Mayinga) causes lethal pneumonia in guinea pigs.

  3. Challenges in testing genetically modified crops for potential increases in endogenous allergen expression for safety.

    PubMed

    Panda, R; Ariyarathna, H; Amnuaycheewa, P; Tetteh, A; Pramod, S N; Taylor, S L; Ballmer-Weber, B K; Goodman, R E

    2013-02-01

    Premarket, genetically modified (GM) plants are assessed for potential risks of food allergy. The major risk would be transfer of a gene encoding an allergen or protein nearly identical to an allergen into a different food source, which can be assessed by specific serum testing. The potential that a newly expressed protein might become an allergen is evaluated based on resistance to digestion in pepsin and abundance in food fractions. If the modified plant is a common allergenic source (e.g. soybean), regulatory guidelines suggest testing for increases in the expression of endogenous allergens. Some regulators request evaluating endogenous allergens for rarely allergenic plants (e.g. maize and rice). Since allergic individuals must avoid foods containing their allergen (e.g. peanut, soybean, maize, or rice), the relevance of the tests is unclear. Furthermore, no acceptance criteria are established and little is known about the natural variation in allergen concentrations in these crops. Our results demonstrate a 15-fold difference in the major maize allergen, lipid transfer protein between nine varieties, and complex variation in IgE binding to various soybean varieties. We question the value of evaluating endogenous allergens in GM plants unless the intent of the modification was production of a hypoallergenic crop.

  4. Integration and Testing Challenges of Small, Multiple Satellite Missions: Experiences from the Space Technology 5 Project

    NASA Technical Reports Server (NTRS)

    Sauerwein, Timothy A.; Gostomski, Thomas

    2007-01-01

    The ST5 payload, part of NASA s New Millennium Program headquartered at JPL, consisted of three micro satellites (approx. 30 kg each) deployed into orbit from the Pegasus XL launch. ST5 was a technology demonstration mission, intended to test new technologies for potential use for future missions. In order to meet the launch date schedule of ST 5, a different approach was required rather than the standard I&T approach used for single, room-sized satellites. The I&T phase was planned for spacecraft #1 to undergo integration and test first, followed by spacecraft #2 and #3 in tandem. A team of engineers and technicians planned and executed the integration of all three spacecraft emphasizing versatility and commonality. They increased their knowledge and efficiency through spacecraft #1 integration and testing and utilized their experience and knowledge to safely execute I&T for spacecraft #2 and #3. Each integration team member could perform many different roles and functions and thus better support activities on any of the three spacecraft. The I&T campaign was completed with STS s successful launch on March 22,2006

  5. Balloon profiles of stratospheric NO2 and HNO3 for testing the heterogeneous hydrolysis of N2O5 on sulfate aerosols

    NASA Technical Reports Server (NTRS)

    Webster, C. R.; May, R. D.; Allen, M.; Jaegle, L.; Mccormick, M. P.

    1994-01-01

    Simultaneous in situ measurements of stratospheric NO2, HNO3, HCl, and CH4 from 34 to 24 km were made in August 1992 from Palestine, Texas, using the Balloon-borne Laser In-Situ Sensor (BLISS) tunable diode laser spectrometer. Although the measurements of NO2, HNO3, and NO2/HNO3 agree well with gas-phase model calculations near 34 km where Stratospheric Aerosol and Gas Experiment (SAGE) 2 data show little sulfate aerosol, this is not true at the lower altitudes where SAGE 2 shows high aerosol loadings. At 24 km the BLISS NO2 and HNO3 measurements are 70% lower and 50% higher, respectively, than the gas phase model predictions, with a measured NO2/HNO3 ratio 5 times smaller. When the heterogeneous hydrolysis of N2O5 and ClONO2 on sulfate aerosol of surface area densities matching the SAGE 2 measurements is added to the model, good agreement with the BLISS measurements is found over the whole altitude range.

  6. Allergy to betalactam antibiotics in children: results of a 20-year study based on clinical history, skin and challenge tests.

    PubMed

    Ponvert, C; Perrin, Y; Bados-Albiero, A; Le Bourgeois, M; Karila, C; Delacourt, C; Scheinmann, P; De Blic, J

    2011-06-01

    Studies based on skin and challenge tests have shown that 12-60% of children with suspected betalactam hypersensitivity were allergic to betalactams. Responses in skin and challenge tests were studied in 1865 children with suspected betalactam allergy (i) to confirm or rule out the suspected diagnosis; (ii) to evaluate diagnostic value of immediate and non-immediate responses in skin and challenge tests; (iii) to determine frequency of betalactam allergy in those children, and (iv) to determine potential risk factors for betalactam allergy. The work-up was completed in 1431 children, of whom 227 (15.9%) were diagnosed allergic to betalactams. Betalactam hypersensitivity was diagnosed in 50 of the 162 (30.9%) children reporting immediate reactions and in 177 of the 1087 (16.7%) children reporting non-immediate reactions (p<0.001). The likelihood of betalactam hypersensitivity was also significantly higher in children reporting anaphylaxis, serum sickness-like reactions, and (potentially) severe skin reactions such as acute generalized exanthematic pustulosis, Stevens-Johnson syndrome, and drug reaction with systemic symptoms than in other children (p<0.001). Skin tests diagnosed 86% of immediate and 31.6% of non-immediate sensitizations. Cross-reactivity and/or cosensitization among betalactams was diagnosed in 76% and 14.7% of the children with immediate and non-immediate hypersensitivity, respectively. The number of children diagnosed allergic to betalactams decreased with time between the reaction and the work-up, probably because the majority of children with severe and worrying reactions were referred for allergological work-up more promptly than the other children. Sex, age, and atopy were not risk factors for betalactam hypersensitivity. In conclusion, we confirm in numerous children that (i) only a few children with suspected betalactam hypersensitivity are allergic to betalactams; (ii) the likelihood of betalactam allergy increases with earliness and

  7. Improved solid aerosol generator

    DOEpatents

    Prescott, D.S.; Schober, R.K.; Beller, J.

    1988-07-19

    An improved solid aerosol generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration. The improved solid aerosol generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated aerosol in a grounded, conical heating chamber, achieving high recovery and flow rates. 2 figs.

  8. Solid aerosol generator

    DOEpatents

    Prescott, Donald S.; Schober, Robert K.; Beller, John

    1992-01-01

    An improved solid aerosol generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration. The improved solid aerosol generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated aerosol in a grounded, conical heating chamber, achieving high recovery and flow rates.

  9. Solid aerosol generator

    DOEpatents

    Prescott, D.S.; Schober, R.K.; Beller, J.

    1992-03-17

    An improved solid aerosol generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration is disclosed. The improved solid aerosol generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated aerosol in a grounded, conical heating chamber, achieving high recovery and flow rates. 2 figs.

  10. The detailed aerosol properties derived using GRASP Algorithm from multi-angular polarimetric POLDER/PARASOL observations

    NASA Astrophysics Data System (ADS)

    Dubovik, Oleg; Litvinov, Pavel; Lapyonok, Tatyana; Ducos, Fabrice; Fuertes, David; Huang, Xin; Derimian, Yevgeny; Ovigneur, Bertrand; Descloitres, Jacques

    2015-04-01

    The presentation introduces a new aerosol product derived from multi-angular polarimetric POLDER/PARASOL observations using recently developed GRASP algorithm The GRASP (Generalized Retrieval of Aerosol and Surface Properties) algorithm described by Dubovik et al. (2011, 2014) derives an extended set of aerosol parameters including detailed particle size distribution, spectral refractive index, single scattering albedo and the fraction of non-spherical particles. Over land GRASP simultaneously retrieves properties of both aerosol and underlying surface. The robust performance of algorithm was illustrated in a series of numerical tests and real data case studies. However, the algorithm is significantly slower than conventional look-up-table retrievals because it performs all radiative transfer calculations on-line. This is why the application of the algorithm for processing large volumes of satellite data was considered as unacceptably challenging task. During two last years GRASP algorithm and its operational retrieval environment has been significantly optimized, improved and adapted for processing extended set of observational data. Hence, here we demonstrate the first results of GRASP aerosol products obtained from large data sets of PARASOL/POLDER observations. It should be noted that in addition the core retrieved aerosol and surface parameters GRASP output may include a variety of user-oriented products including values of daily fluxes and aerosol radiative forcing. 1. Dubovik, O., M. Herman, A. Holdak, T. Lapyonok, D. Tanré, J. L. Deuzé, F. Ducos, A. Sinyuk, and A. Lopatin, "Statistically optimized inversion algorithm for enhanced retrieval of aerosol properties from spectral multi-angle polarimetric satellite observations", Atmos. Meas. Tech., 4, 975-1018, 2011. 2. Dubovik, O., T. Lapyonok, P. Litvinov, M. Herman, D. Fuertes, F. Ducos, A. Lopatin, A. Chaikovsky, B. Torres, Y. Derimian, X. Huang, M. Aspetsberger, and C. Federspiel "GRASP: a versatile

  11. Current practices and challenges in the standardization and harmonization of clinical laboratory tests.

    PubMed

    Vesper, Hubert W; Myers, Gary L; Miller, W Greg

    2016-09-01

    Effective patient care, clinical research, and public health efforts require comparability of laboratory results independent of time, place, and measurement procedure. Comparability is achieved by establishing metrological traceability, which ensures that measurement procedures measure the same quantity and that the calibration of measurement procedures is traceable to a common reference system consisting of reference methods and materials. Whereas standardization ensures traceability to the International System of Units, harmonization ensures traceability to a reference system agreed on by convention. This article provides an overview of standardization and harmonization with an emphasis on commutability as an important variable that affects testing accuracy. Commutability of reference materials is required to ensure that traceability is established appropriately and that laboratory results are comparable. The use of noncommutable reference materials leads to inaccurate results. Whereas procedures and protocols for standardizing measurements are established and have been successfully applied in efforts such as the Hormones Standardization Program of the CDC, harmonization activities require new, more complex procedures and approaches. The American Association for Clinical Chemistry, together with its domestic and international partners, formed the International Consortium for Harmonization of Clinical Laboratory Results to coordinate harmonization efforts. Reference systems, as well as procedures and protocols to establish traceability of clinical laboratory tests, have been established and continue to be developed by national and international groups and organizations. Serum tests of thyroid function, including those for the thyroid hormones thyroxine and triiodothyronine, are among the clinical procedures for which standardization efforts are well under way. Approaches to the harmonization of measurement procedures for serum concentrations of thyroid

  12. Challenges of Cold Conditioning and Static Testing the Ares Demonstration Motor (DM-2)

    NASA Technical Reports Server (NTRS)

    Quinn, Shyla; Davis, Larry C.

    2011-01-01

    The Ares first stage rocket is a "human-rated" motor capable of producing and sustaining 3.5 million pounds of thrust throughout it s two-minute burn period. A series of demonstration motors (DM) will be tested in different conditioned environments to confirm they meet all design specifications. The second demonstration motor (DM-2) was designated to be a "cold motor", this means the internal propellant mean bulk temperature (PMBT) was 40 +5\\-3 F. The motor was subjected to subfreezing temperatures for two months.

  13. Safety Testing of Dengue-2 and Dengue-4 Viruses for Use in Human Challenge Experiments

    DTIC Science & Technology

    1988-04-01

    16.6 IIJI 2 N ,RSLIO JS ’, %AN -T N ," 1 0 % :.i. AD Ln MC.tILE (UiO Safety Testinq of Dengue -2 and Denque-4 Viruses for Use in Human Chal, nqe...ELEMENT NO. NO. 3M16 NO. ACCESSION NO. 62770A 2770A871 AA 110 11. TITLE (Include Security Classification) Safety Testing of Dengue -2 and Dengue -4 Viruses...if necessary and identify by block number) FIELD GROUP SUB-GROUP Dengue Fever, Viruses, Mice, Rabbits, Guinea Pig, 06 13 Tropical Medicine, Virology

  14. Challenges of implementing digital technology in motion picture distribution and exhibition: testing and evaluation methodology

    NASA Astrophysics Data System (ADS)

    Swartz, Charles S.

    2003-05-01

    The process of distributing and exhibiting a motion picture has changed little since the Lumière brothers presented the first motion picture to an audience in 1895. While this analog photochemical process is capable of producing screen images of great beauty and expressive power, more often the consumer experience is diminished by third generation prints and by the wear and tear of the mechanical process. Furthermore, the film industry globally spends approximately $1B annually manufacturing and shipping prints. Alternatively, distributing digital files would theoretically yield great benefits in terms of image clarity and quality, lower cost, greater security, and more flexibility in the cinema (e.g., multiple language versions). In order to understand the components of the digital cinema chain and evaluate the proposed technical solutions, the Entertainment Technology Center at USC in 2000 established the Digital Cinema Laboratory as a critical viewing environment, with the highest quality film and digital projection equipment. The presentation describes the infrastructure of the Lab, test materials, and testing methodologies developed for compression evaluation, and lessons learned up to the present. In addition to compression, the Digital Cinema Laboratory plans to evaluate other components of the digital cinema process as well.

  15. Aerosol Climate Time Series in ESA Aerosol_cci

    NASA Astrophysics Data System (ADS)

    Popp, Thomas; de Leeuw, Gerrit; Pinnock, Simon

    2016-04-01

    Within the ESA Climate Change Initiative (CCI) Aerosol_cci (2010 - 2017) conducts intensive work to improve algorithms for the retrieval of aerosol information from European sensors. Meanwhile, full mission time series of 2 GCOS-required aerosol parameters are completely validated and released: Aerosol Optical Depth (AOD) from dual view ATSR-2 / AATSR radiometers (3 algorithms, 1995 - 2012), and stratospheric extinction profiles from star occultation GOMOS spectrometer (2002 - 2012). Additionally, a 35-year multi-sensor time series of the qualitative Absorbing Aerosol Index (AAI) together with sensitivity information and an AAI model simulator is available. Complementary aerosol properties requested by GCOS are in a "round robin" phase, where various algorithms are inter-compared: fine mode AOD, mineral dust AOD (from the thermal IASI spectrometer, but also from ATSR instruments and the POLDER sensor), absorption information and aerosol layer height. As a quasi-reference for validation in few selected regions with sparse ground-based observations the multi-pixel GRASP algorithm for the POLDER instrument is used. Validation of first dataset versions (vs. AERONET, MAN) and inter-comparison to other satellite datasets (MODIS, MISR, SeaWIFS) proved the high quality of the available datasets comparable to other satellite retrievals and revealed needs for algorithm improvement (for example for higher AOD values) which were taken into account for a reprocessing. The datasets contain pixel level uncertainty estimates which were also validated and improved in the reprocessing. For the three ATSR algorithms the use of an ensemble method was tested. The paper will summarize and discuss the status of dataset reprocessing and validation. The focus will be on the ATSR, GOMOS and IASI datasets. Pixel level uncertainties validation will be summarized and discussed including unknown components and their potential usefulness and limitations. Opportunities for time series extension

  16. Small-scale Rainfall Challenges Tested with Semi-distributed and Distributed Hydrological Models

    NASA Astrophysics Data System (ADS)

    Ichiba, Abdellah; Tchiguirinskaia, Ioulia; Gires, Auguste; Schertzer, Daniel; Bompard, Philippe

    2016-04-01

    Nowadays, there is a growing interest on small-scale rainfall information, provided by weather radars, to be used in urban water management and decision-making. Indeed, it helps to better understand the essential interactions between natural and man-made urban environments, both being complex systems. However the integration of this information in hydrological models remains a big challenge. In fact, urban water managers often rely on lumped or semi-distributed models with much coarser data resolution. The scope of this work is to investigate the sensitivity of two hydrological models to small-scale rainfall, and their potential improvements to integrate wholly the small-scale information. The case study selected to perform this study is a small urban catchment (245 ha), located at Val-de-Marne county (southeast of Paris, France). Investigations were conducted using either CANOE model, a semi-distributed conceptual model that is widely used in France for urban modeling, or a fully distributed and physically based model, Multi-Hydro, developed at Ecole des Ponts ParisTech (www hmco-dev.enpc.fr/Tools-Training/Tools/Multi-Hydro.php). Initially, in CANOE model the catchment was divided into 9 sub-catchments with size ranging from 1ha to 76ha. A refinement process was conduced in the framework of this investigation in order to improve the model resolution by considering higher number of smaller sub-catchments. The new configuration consists of 44 sub-catchments with size ranging from 1ha-14ha. The Multi-Hydro modeling approach consists on rasterizing the catchment information to a regular spatial grid of a resolution chosen by the user. Each pixel is then affected by specific information, e.g., a unique land type per pixel, for which hydrological and physical properties are set. First of all, both models were validated with respect to real flow measurements using three types of rainfall data: (1) point measurement data coming form the Sucy-en-Brie rain gauge; (2) Meteo

  17. Transitioning to Low-GWP Alternatives in Aerosols

    EPA Pesticide Factsheets

    This fact sheet provides information on low-GWP alternatives for non-medical commercial aerosols, relevant to the Montreal Protocol. It discusses HFC alternatives, market trends, and challenges to market entry for alternatives and potential solutions.

  18. Aerosol algorithm evaluation within aerosol-CCI

    NASA Astrophysics Data System (ADS)

    Kinne, Stefan; Schulz, Michael; Griesfeller, Jan

    Properties of aerosol retrievals from space are difficult. Even data from dedicated satellite sensors face contaminations which limit the accuracy of aerosol retrieval products. Issues are the identification of complete cloud-free scenes, the need to assume aerosol compositional features in an underdetermined solution space and the requirement to characterize the background at high accuracy. Usually the development of aerosol is a slow process, requiring continuous feedback from evaluations. To demonstrate maturity, these evaluations need to cover different regions and seasons and many different aerosol properties, because aerosol composition is quite diverse and highly variable in space and time, as atmospheric aerosol lifetimes are only a few days. Three years ago the ESA Climate Change Initiative started to support aerosol retrieval efforts in order to develop aerosol retrieval products for the climate community from underutilized ESA satellite sensors. The initial focus was on retrievals of AOD (a measure for the atmospheric column amount) and of Angstrom (a proxy for aerosol size) from the ATSR and MERIS sensors on ENVISAT. The goal was to offer retrieval products that are comparable or better in accuracy than commonly used NASA products of MODIS or MISR. Fortunately, accurate reference data of ground based sun-/sky-photometry networks exist. Thus, retrieval assessments could and were conducted independently by different evaluation groups. Here, results of these evaluations for the year 2008 are summarized. The capability of these newly developed retrievals is analyzed and quantified in scores. These scores allowed a ranking of competing efforts and also allow skill comparisons of these new retrievals against existing and commonly used retrievals.

  19. Pharmacokinetics and pharmacodynamics of oral mecamylamine - development of a nicotinic acetylcholine receptor antagonist cognitive challenge test using modelling and simulation.

    PubMed

    Alvarez-Jimenez, Ricardo; Baakman, Anne Catrien; Stevens, Jasper; Goulooze, Sebastiaan C; Hart, Ellen P; Rissmann, Robert; van Gerven, Joop Ma; Groeneveld, Geert Jan

    2017-02-01

    A pharmacologic challenge model with a nicotinic antagonist could be an important tool not only to understand the complex role of the nicotinic cholinergic system in cognition, but also to develop novel compounds acting on the nicotinic acetylcholine receptor. The objective was to develop a pharmacokinetic-pharmacodynamic (PKPD) model using nonlinear mixed effects (NLME) methods to quantitate the pharmacokinetics of three oral mecamylamine doses (10, 20 and 30 mg) and correlate the plasma concentrations to the pharmacodynamic effects on a cognitive and neurophysiologic battery of tests in healthy subjects. A one-compartment linear kinetic model best described the plasma concentrations of mecamylamine. Mecamylamine's estimated clearance was 0.28 ± 0.015 L min(-1). The peripheral volume of distribution (291 ± 5.15 L) was directly related to total body weight. Mecamylamine impaired the accuracy and increased the reaction time in tests evaluating short term working memory with a steep increase in the concentration-effect relationship at plasma concentrations below 100 μg L(-1). On the other hand, mecamylamine induced a decrease in performance of tests evaluating visual and fine motor coordination at higher plasma concentrations (EC50 97 μg L(-1)). Systolic and diastolic blood pressure decreased exponentially after a plasma mecamylamine concentration of 80 μg L(-1), a known effect previously poorly studied in healthy subjects. The developed mecamylamine PKPD model was used to quantify the effects of nicotinic blockade in a set of neurophysiological tests in humans with the goal to provide insight into the physiology and pharmacology of the nicotinic system in humans and the possibility to optimize future trials that use mecamylamine as a pharmacological challenge.

  20. Potential sources of 2-aminoacetophenone to confound the Pseudomonas aeruginosa breath test, including analysis of a food challenge study.

    PubMed

    Scott-Thomas, Amy; Pearson, John; Chambers, Stephen

    2011-12-01

    2-Aminoacetophenone can be detected in the breath of Pseudomonas aeruginosa colonized cystic fibrosis patients; however, low levels were also detected in a small proportion of healthy subjects. It was hypothesized that food, beverages, cosmetics or medications could be a source of contamination of 2-aminoacetophenone in breath. To determine the potential confounding of these products on 2-aminoacetophenone breath analysis, screening for this volatile was performed in the laboratory by gas chromatography/mass spectrometry and a food challenge study carried out. 2-Aminoacetophenone was detected in four of the 78 samples tested in vitro: corn chips and canned tuna (high pmol mol(-1)) and egg white and one of the three beers (low pmol mol(-1)). No 2-aminoacetophenone was detected in the CF medication or cosmetics tested. Twenty-eight out of 30 environmental air samples were negative for 2-aminoacetophenone (below 50 pmol mol(-1)). A challenge study with ten healthy subjects was performed to determine if 2-aminoacetophenone from corn chips was detectable on the breath after consumption. Analysis of mixed breath samples reported that the levels of 2-aminoacetophenone were immediately elevated after corn chip consumption, but after 2 h the level of 2-aminoacetophenone had reduced back to the 'baseline' for each subject.

  1. Non-invasive prenatal testing for aneuploidy and beyond: challenges of responsible innovation in prenatal screening

    PubMed Central

    Dondorp, Wybo; de Wert, Guido; Bombard, Yvonne; Bianchi, Diana W; Bergmann, Carsten; Borry, Pascal; Chitty, Lyn S; Fellmann, Florence; Forzano, Francesca; Hall, Alison; Henneman, Lidewij; Howard, Heidi C; Lucassen, Anneke; Ormond, Kelly; Peterlin, Borut; Radojkovic, Dragica; Rogowski, Wolf; Soller, Maria; Tibben, Aad; Tranebjærg, Lisbeth; van El, Carla G; Cornel, Martina C

    2015-01-01

    This paper contains a joint ESHG/ASHG position document with recommendations regarding responsible innovation in prenatal screening with non-invasive prenatal testing (NIPT). By virtue of its greater accuracy and safety with respect to prenatal screening for common autosomal aneuploidies, NIPT has the potential of helping the practice better achieve its aim of facilitating autonomous reproductive choices, provided that balanced pretest information and non-directive counseling are available as part of the screening offer. Depending on the health-care setting, different scenarios for NIPT-based screening for common autosomal aneuploidies are possible. The trade-offs involved in these scenarios should be assessed in light of the aim of screening, the balance of benefits and burdens for pregnant women and their partners and considerations of cost-effectiveness and justice. With improving screening technologies and decreasing costs of sequencing and analysis, it will become possible in the near future to significantly expand the scope of prenatal screening beyond common autosomal aneuploidies. Commercial providers have already begun expanding their tests to include sex-chromosomal abnormalities and microdeletions. However, multiple false positives may undermine the main achievement of NIPT in the context of prenatal screening: the significant reduction of the invasive testing rate. This document argues for a cautious expansion of the scope of prenatal screening to serious congenital and childhood disorders, only following sound validation studies and a comprehensive evaluation of all relevant aspects. A further core message of this document is that in countries where prenatal screening is offered as a public health programme, governments and public health authorities should adopt an active role to ensure the responsible innovation of prenatal screening on the basis of ethical principles. Crucial elements are the quality of the screening process as a whole (including non

  2. Non-invasive prenatal testing for aneuploidy and beyond: challenges of responsible innovation in prenatal screening.

    PubMed

    Dondorp, Wybo; de Wert, Guido; Bombard, Yvonne; Bianchi, Diana W; Bergmann, Carsten; Borry, Pascal; Chitty, Lyn S; Fellmann, Florence; Forzano, Francesca; Hall, Alison; Henneman, Lidewij; Howard, Heidi C; Lucassen, Anneke; Ormond, Kelly; Peterlin, Borut; Radojkovic, Dragica; Rogowski, Wolf; Soller, Maria; Tibben, Aad; Tranebjærg, Lisbeth; van El, Carla G; Cornel, Martina C

    2015-11-01

    This paper contains a joint ESHG/ASHG position document with recommendations regarding responsible innovation in prenatal screening with non-invasive prenatal testing (NIPT). By virtue of its greater accuracy and safety with respect to prenatal screening for common autosomal aneuploidies, NIPT has the potential of helping the practice better achieve its aim of facilitating autonomous reproductive choices, provided that balanced pretest information and non-directive counseling are available as part of the screening offer. Depending on the health-care setting, different scenarios for NIPT-based screening for common autosomal aneuploidies are possible. The trade-offs involved in these scenarios should be assessed in light of the aim of screening, the balance of benefits and burdens for pregnant women and their partners and considerations of cost-effectiveness and justice. With improving screening technologies and decreasing costs of sequencing and analysis, it will become possible in the near future to significantly expand the scope of prenatal screening beyond common autosomal aneuploidies. Commercial providers have already begun expanding their tests to include sex-chromosomal abnormalities and microdeletions. However, multiple false positives may undermine the main achievement of NIPT in the context of prenatal screening: the significant reduction of the invasive testing rate. This document argues for a cautious expansion of the scope of prenatal screening to serious congenital and childhood disorders, only following sound validation studies and a comprehensive evaluation of all relevant aspects. A further core message of this document is that in countries where prenatal screening is offered as a public health programme, governments and public health authorities should adopt an active role to ensure the responsible innovation of prenatal screening on the basis of ethical principles. Crucial elements are the quality of the screening process as a whole (including non

  3. HDR Opportunities and Challenges Beyond the Long-Term Flow Test

    SciTech Connect

    Duchane, David

    1992-03-24

    The long term flow test (LTFT) of the worlds largest, deepest, and hottest hot dry rock (HDR) reservoir currently underway at Fenton Hill, NM, is expected to demonstrate that thermal energy can be mined from hot rock within the earth on a sustainable basis with minimal water consumption. This test will simulate the operations of a commercial facility in some ways, but it will not show that energy from HDR can be produced at a variety of locations with different geological settings. Since the Fenton Hill system was designed as a research facility rather than strictly for production purposes, it will also not demonstrate economic viability, although it may well give indications of system modifications needed for economic HDR operations. A second production site must be constructed, ideally under the direction of the private geothermal community, to begin the process of proving that the vast HDR resources can be accessed on a worldwide scale. This facility should be designed and engineered to produce and market energy at competitive prices. At the same time, a wide variety of techniques to advance the state-of-the-art of HDR technology must be pursued to develop this infant technology rapidly to its maximum potential. A number of design and operational techniques have been conceived which may lead to improved economics in HDR systems. After careful technical and economic scrutiny, those showing merit should be vigorously pursued. Finally, research and development work in areas such as reservoir interrogation, and system modeling must be accelerated to increase the competitiveness and geographical applications of HDR and the geothermal industry in general. This paper addresses the above issues in detail and outlines possible paths to future prosperity for the commercial geothermal industry.

  4. PD-L1 testing for lung cancer in the UK: recognizing the challenges for implementation.

    PubMed

    Cree, Ian A; Booton, Richard; Cane, Paul; Gosney, John; Ibrahim, Merdol; Kerr, Keith; Lal, Rohit; Lewanski, Conrad; Navani, Neal; Nicholson, Andrew G; Nicolson, Marianne; Summers, Yvonne

    2016-08-01

    A new approach to the management of non-small-cell lung cancer (NSCLC) has recently emerged that works by manipulating the immune checkpoint controlled by programmed death receptor 1 (PD-1) and its ligand programmed death ligand 1 (PD-L1). Several drugs targeting PD-1 (pembrolizumab and nivolumab) or PD-L1 (atezolizumab, durvalumab, and avelumab) have been approved or are in the late stages of development. Inevitably, the introduction of these drugs will put pressure on healthcare systems, and there is a need to stratify patients to identify those who are most likely to benefit from such treatment. There is evidence that responsiveness to PD-1 inhibitors may be predicted by expression of PD-L1 on neoplastic cells. Hence, there is considerable interest in using PD-L1 immunohistochemical staining to guide the use of PD-1-targeted treatments in patients with NSCLC. This article reviews the current knowledge about PD-L1 testing, and identifies current research requirements. Key factors to consider include the source and timing of sample collection, pre-analytical steps (sample tracking, fixation, tissue processing, sectioning, and tissue prioritization), analytical decisions (choice of biomarker assay/kit and automated staining platform, with verification of standardized assays or validation of laboratory-devised techniques, internal and external quality assurance, and audit), and reporting and interpretation of the results. This review addresses the need for integration of PD-L1 immunohistochemistry with other tests as part of locally agreed pathways and protocols. There remain areas of uncertainty, and guidance should be updated regularly as new information becomes available.

  5. False-positive diatom test: a real challenge? A post-mortem study using standardized protocols.

    PubMed

    Lunetta, Philippe; Miettinen, Arto; Spilling, Kristian; Sajantila, Antti

    2013-09-01

    The main criticism of the validity of the diatom test for the diagnosis of drowning is based on the potential ante- and post-mortem penetration of diatoms and the finding of diatoms in bodies of non-drowned human beings. However, qualitative and quantitative studies on diatoms in organs of the non-drowned have yielded both conflicting and contradictory results. In the present study, we have analysed under standardised methods the diatom content in several organs of 14 non-drowned human bodies. Overall, only 9 diatoms (6 entire, 3 fragmented) were disclosed in 6 of the 14 non-drowned bodies. Each of these 6 cadavers had only a single "positive" organ. Six diatoms were found in the bone marrow, 2 in the lung, and one in the pleural liquid. No diatoms were recovered from the brain, liver, kidney, or blood samples of any of these 14 bodies. Moreover, in five additional cadavers, whose lungs were injected, prior autopsy, with a 3.5L solution containing a bi-cellulate diatom culture (Thalassiosira baltica, Thalassiosira levanderi) via tracheostomy, a few diatoms appeared in the pleural cavity and in the blood from the left heart chamber, but none in any other internal organs investigated. The results of the presented study demonstrate that the issue of the false-positive diatom test should not be a logical impediment to the performance of the diatom method. However, strict and standardized protocols aimed at avoiding contamination during sample preparation must be used, appropriate separation values set and taxonomic analysis of all diatoms performed.

  6. Emission factors of fine particles, carbonaceous aerosols and traces gases from road vehicles: Recent tests in an urban tunnel in the Pearl River Delta, China

    NASA Astrophysics Data System (ADS)

    Zhang, Yanli; Wang, Xinming; Li, Guanghui; Yang, Weiqiang; Huang, Zhonghui; Zhang, Zhou; Huang, Xinyu; Deng, Wei; Liu, Tengyu; Huang, Zuzhao; Zhang, Zhanyi

    2015-12-01

    Motor vehicles contribute primarily and secondarily to air quality problems due to fine particle (PM2.5) and ozone (O3) pollution in China's megacities. Characterizing vehicle emission with the rapid change of vehicle numbers and fleet compositions is vital for both bottom-up emission survey and top-down source apportioning. To obtain emission factors (EFs) of PM2.5, carbonaceous aerosols and trace gases for road vehicles, in urban Guangzhou we conducted a field campaign in 2014 in the Zhujiang Tunnel, a heavily burdened tunnel with about 40,000 motor vehicles passing through each of its two separated bores per day. PM2.5 and volatile organic compounds (VOCs) were sampled for offline analysis while trace gases including SO2, NOx and CO were measured online and in situ. An eddy covariance system with an integrated 3-D sonic anemometer was also adopted to measure CO2 and winds inside the tunnel. We recorded an average fleet composition of 61% light-duty gasoline vehicles (LDVs) + 12% heavy-duty diesel vehicles (HDVs) + 27% liquefied petroleum gas vehicles (LPGVs), and EFs of 82.7 ± 28.3, 19.3 ± 4.7 and 13.3 ± 3.3 mg veh-1 km-1, respectively, for PM2.5, organic carbon (OC) and elemental carbon (EC). These EFs were respectively 23.4%, 18.3% and 72.3% lower when compared to that measured in the same tunnel in 2004. EFs of PM2.5, OC and EC were higher at night time (148 ± 126, 29 ± 24 and 21 ± 18 mg veh-1 km-1, respectively) due to significantly elevated fractions of HDVs in the traffic fleets. An average ratio of OC to EC 1.45 from this tunnel study was much higher than that of ∼0.5 in previous tunnel studies. The EFs of SO2, NOx, CO, CO2 and NMHCs for road traffic were also obtained from our tunnel tests, and they were 20.7 ± 2.9, (1.29 ± 0.2)E+03, (3.10 ± 0.68)E+03, (3.90 ± 0.49)E+05, and 448 ± 39 mg veh-1 km-1, respectively.

  7. Implementation of the Missing Aerosol Physics into LLNL IMPACT

    SciTech Connect

    Chuang, C

    2005-02-09

    characteristics and composition of aerosols. These processes, together with other physical properties (i.e., size, density, and refractive index), determine the atmospheric lifetime of aerosols and their radiative forcing. To better represent physical properties of aerosols, we adapted an aerosol microphysics model that simulates aerosol size distribution. Work toward this goal was done in collaboration with Professor Anthony Wexler of University of California at Davis. Professor Wexler's group has developed sectional models of atmospheric aerosol dynamics that include an arbitrary number of size sections and chemical compounds or compound classes. The model, AIM (Aerosol Inorganic Model), is designed to predict the mass distribution and composition of urban and regional particulate matter (''Sun and Wexler'', 1998a, b). This model is currently incorporated into EPA's Models-3 air quality modeling platform/CMAQ (Community Multiscale Air Quality) to test its performance with previous simulations of CMAQ over the continental US.

  8. Implementation challenges for designing integrated in vitro testing strategies (ITS) aiming at reducing and replacing animal experimentation.

    PubMed

    De Wever, Bart; Fuchs, Horst W; Gaca, Marianna; Krul, Cyrille; Mikulowski, Stan; Poth, Albrecht; Roggen, Erwin L; Vilà, Maya R

    2012-04-01

    At the IVTIP (in vitro testing industrial platform) meeting of November 26th 2009 entitled 'Toxicology in the 21st century ('21C')--working our way towards a visionary reality' all delegates endorsed the emerging concept of the '21C' vision as the way forward to enable a thorough, reliable and systematic approach to future toxicity testing without the use of animals. One of the emerging concepts focused on integrating a defined number of tests modelling in vivo-relevant and well-characterised toxicity pathways representing mechanistic endpoints. At this meeting the importance of Integrated Testing Strategies (ITS) as tools towards reduction and eventually replacement of the animals currently used for hazard identification and risk assessment was recognised. A follow-up IVTIP Spring 2010 meeting entitled 'Integrated In Vitro Testing Strategies (ITS)--Implementation Challenges' was organised to address pending questions about ITS. This report is not a review of the ITS literature, but a summary of the discussions triggered by presented examples on how to develop and implement ITS. Contrasts between pharmaceutical and chemical industry, as well as a list of general but practical aspects to be considered while developing an ITS emerged from the discussions. In addition, current recommendations on the validation of ITS were discussed. In conclusion, the outcome of this workshop improved the understanding of the participants of some important factors that may impact the design of an ITS in function of its purpose (e.g., screening, or early decision making versus regulatory), the context in which they need to be applied (e.g., ICH guidelines, REACH) and the status and quality of the available tools. A set of recommendations of best practices was established and the importance of the applicability of the individual tests as well as the testing strategy itself was highlighted.

  9. Prenatal molecular testing for Beckwith-Wiedemann and Silver-Russell syndromes: a challenge for molecular analysis and genetic counseling.

    PubMed

    Eggermann, Thomas; Brioude, Frédéric; Russo, Silvia; Lombardi, Maria P; Bliek, Jet; Maher, Eamonn R; Larizza, Lidia; Prawitt, Dirk; Netchine, Irène; Gonzales, Marie; Grønskov, Karen; Tümer, Zeynep; Monk, David; Mannens, Marcel; Chrzanowska, Krystyna; Walasek, Malgorzata K; Begemann, Matthias; Soellner, Lukas; Eggermann, Katja; Tenorio, Jair; Nevado, Julián; Moore, Gudrun E; Mackay, Deborah Jg; Temple, Karen; Gillessen-Kaesbach, Gabriele; Ogata, Tsutomu; Weksberg, Rosanna; Algar, Elizabeth; Lapunzina, Pablo

    2016-06-01

    Beckwith-Wiedemann and Silver-Russell syndromes (BWS/SRS) are two imprinting disorders (IDs) associated with disturbances of the 11p15.5 chromosomal region. In BWS, epimutations and genomic alterations within 11p15.5 are observed in >70% of patients, whereas in SRS they are observed in about 60% of the cases. In addition, 10% of the SRS patients carry a maternal uniparental disomy of chromosome 7 11p15.5. There is an increasing demand for prenatal testing of these disorders owing to family history, indicative prenatal ultrasound findings or aberrations involving chromosomes 7 and 11. The complex molecular findings underlying these disorders are a challenge not only for laboratories offering these tests but also for geneticists counseling affected families. The scope of counseling must consider the range of detectable disturbances and their origin, the lack of precise quantitative knowledge concerning the inheritance and recurrence risks for the epigenetic abnormalities, which are hallmarks of these developmental disorders. In this paper, experts in the field of BWS and SRS, including members of the European network of congenital IDs (EUCID.net; www.imprinting-disorders.eu), put together their experience and work in the field of 11p15.5-associated IDs with a focus on prenatal testing. Altogether, prenatal tests of 160 fetuses (122 referred for BWS, 38 for SRS testing) from 5 centers were analyzed and reviewed. We summarize the current knowledge on BWS and SRS with respect to diagnostic testing, the consequences for prenatal genetic testing and counseling and our cumulative experience in dealing with these disorders.

  10. Evaluation of the discmini personal aerosol monitor for submicrometer sodium chloride and metal aerosols

    NASA Astrophysics Data System (ADS)

    Mills, Jessica Breyan

    This work evaluated the robust, lightweight DiSCmini (DM) aerosol monitor for its ability to measure the concentration and mean diameter of submicrometer aerosols. Tests were conducted with monodispersed and polydispersed aerosols composed of two particle types (sodium chloride, NaCl, and spark generated metal particles, which simulate particles found in welding fume) at three different steady-state concentration ranges (Low, <103; Medium, 103-104; and High, >104 particles/cm3). Particle number concentration, lung deposited surface area (LDSA) concentration, and mean size measured with the DM were compared to those measured with reference instruments, a scanning mobility particle sizer (SMPS) and a handheld condensation particle counter (CPC). Particle number concentrations measured with the DM were within 16% of those measured by the CPC for polydispersed aerosols. Poorer agreement was observed for monodispersed aerosols (+/-35% for most tests and +101% for 300-nm NaCl). LDSA concentrations measured by the DM were 96% to 155% of those estimated with the SMPS. The geometric mean diameters measured with the DM were within 30% of those measured with the SMPS for monodispersed aerosols and within 25% for polydispersed aerosols (except for the case when the aerosol contained a substantial number of particles larger than 300 nm). The accuracy of the DM is reasonable for particles smaller than 300 nm but caution should be exercised when particles larger than 300 nm are present.

  11. Moving towards a reliable HIV incidence test - current status, resources available, future directions and challenges ahead.

    PubMed

    Murphy, G; Pilcher, C D; Keating, S M; Kassanjee, R; Facente, S N; Welte, A; Grebe, E; Marson, K; Busch, M P; Dailey, P; Parkin, N; Osborn, J; Ongarello, S; Marsh, K; Garcia-Calleja, J M

    2017-04-01

    In 2011 the Incidence Assay Critical Path Working Group reviewed the current state of HIV incidence assays and helped to determine a critical path to the introduction of an HIV incidence assay. At that time the Consortium for Evaluation and Performance of HIV Incidence Assays (CEPHIA) was formed to spur progress and raise standards among assay developers, scientists and laboratories involved in HIV incidence measurement and to structure and conduct a direct independent comparative evaluation of the performance of 10 existing HIV incidence assays, to be considered singly and in combinations as recent infection test algorithms. In this paper we report on a new framework for HIV incidence assay evaluation that has emerged from this effort over the past 5 years, which includes a preliminary target product profile for an incidence assay, a consensus around key performance metrics along with analytical tools and deployment of a standardized approach for incidence assay evaluation. The specimen panels for this evaluation have been collected in large volumes, characterized using a novel approach for infection dating rules and assembled into panels designed to assess the impact of important sources of measurement error with incidence assays such as viral subtype, elite host control of viraemia and antiretroviral treatment. We present the specific rationale for several of these innovations, and discuss important resources for assay developers and researchers that have recently become available. Finally, we summarize the key remaining steps on the path to development and implementation of reliable assays for monitoring HIV incidence at a population level.

  12. Flight Test Evaluation of Synthetic Vision Concepts at a Terrain Challenged Airport

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Prince, Lawrence J., III; Bailey, Randell E.; Arthur, Jarvis J., III; Parrish, Russell V.

    2004-01-01

    NASA's Synthetic Vision Systems (SVS) Project is striving to eliminate poor visibility as a causal factor in aircraft accidents as well as enhance operational capabilities of all aircraft through the display of computer generated imagery derived from an onboard database of terrain, obstacle, and airport information. To achieve these objectives, NASA 757 flight test research was conducted at the Eagle-Vail, Colorado airport to evaluate three SVS display types (Head-up Display, Head-Down Size A, Head-Down Size X) and two terrain texture methods (photo-realistic, generic) in comparison to the simulated Baseline Boeing-757 Electronic Attitude Direction Indicator and Navigation/Terrain Awareness and Warning System displays. The results of the experiment showed significantly improved situation awareness, performance, and workload for SVS concepts compared to the Baseline displays and confirmed the retrofit capability of the Head-Up Display and Size A SVS concepts. The research also demonstrated that the tunnel guidance display concept used within the SVS concepts achieved required navigation performance (RNP) criteria.

  13. Asbestos penetration test system for clothing materials

    SciTech Connect

    Bradley, O.D.; Stampfer, J.F.; Sandoval, A.N.; Heath, C.A.; Cooper, M.H.

    1997-04-01

    For hazardous work such as asbestos abatement, there is a need to assess protective clothing fabrics and seam constructions to assure an adequate barrier against hazardous material. The penetration of aerosols through fabrics usually is measured by challenging fabric samples with an aerosol stream at a constant specified airflow. To produce the specified airflow, pressure differentials across the samples often are higher than exist in a work environment. This higher airflow results in higher aerosol velocities through the fabric and, possibly, measured penetration values not representative of those actually experienced in the field. The objective of the reported work was to develop a test method that does not require these higher airflows. The authors have designed and fabricated a new system that tests fabric samples under a low, constant, specified pressure differential across the samples. This differential is adjustable from tenths of a mm Water Gauge (hundredths of an in WG) to over 25-mm WG (1-in WG). The system operates at a pressure slightly lower than its surroundings. Although designed primarily for asbestos, the system is equally applicable to the testing of other aerosols by changing the aerosol generator and detector. Through simple modification of the sample holders, the test apparatus would be capable of evaluating seam and closure constructions.

  14. Technological advances in diagnostic testing for von Willebrand disease: new approaches and challenges.

    PubMed

    Hayward, C P M; Moffat, K A; Graf, L

    2014-06-01

    Diagnostic tests for von Willebrand disease (VWD) are important for the assessment of VWD, which is a commonly encountered bleeding disorder worldwide. Technical innovations have been applied to improve the precision and lower limit of detection of von Willebrand factor (VWF) assays, including the ristocetin cofactor activity assay (VWF:RCo) that uses the antibiotic ristocetin to induce plasma VWF binding to glycoprotein (GP) IbIXV on target platelets. VWF-collagen-binding assays, depending on the type of collagen used, can improve the detection of forms of VWD with high molecular weight VWF multimer loss, although the best method is debatable. A number of innovations have been applied to VWF:RCo (which is commonly performed on an aggregometer), including replacing the target platelets with immobilized GPIbα, and quantification by an enzyme-linked immunosorbent assay (ELISA), immunoturbidimetric, or chemiluminescent end-point. Some common polymorphisms in the VWF gene that do not cause bleeding are associated with falsely low VWF activity by ristocetin-dependent methods. To overcome the need for ristocetin, some new VWF activity assays use gain-of-function GPIbα mutants that bind VWF without the need for ristocetin, with an improved precision and lower limit of detection than measuring VWF:RCo by aggregometry. ELISA of VWF binding to mutated GPIbα shows promise as a method to identify gain-of-function defects from type 2B VWD. The performance characteristics of many new VWF activity assays suggest that the detection of VWD, and monitoring of VWD therapy, by clinical laboratories could be improved through adopting newer generation VWF assays.

  15. Serotonin transporter genotype modulates HPA axis output during stress: effect of stress, dexamethasone test and ACTH challenge

    PubMed Central

    Sorenson, Andrea N.; Sullivan, Erin C.; Mendoza, Sally P.; Capitanio, John P.; Higley, J. Dee

    2014-01-01

    Background Studies show that the hypothalamic–pituitary–adrenal (HPA) axis is dysregulated in depression. Some studies suggest that variation in the serotonin transporter genotype (hereafter 5HTT) modulates both risk for depression and psychopathological HPA axis responsiveness. Rhesus monkeys are well suited to model such relationships. Rhesus macaque models of human psychopathology have assessed the effect of the serotonin transporter (rh5HTT) on levels of cortisol in stressed subjects. These studies show that that under conditions of stress, heterozygous females (Ls) reared under adversity exhibit high levels of cortisol. Studies have not to our knowledge, however, assessed the potential additive effect on the cortisol response in a number of macaque subjects homozygous for the serotonin transporter short allele (ss). Moreover, little is known about the level of the central or peripheral nervous system at which the 5HTT genotype acts to modulate the cortisol response. Methods This study assesses a relatively large number of subjects homozygous and heterozygous for the rh5HTT short and long alleles (a) during stress; (b) following a dexamethasone suppression test; and (c) following an adrenocorticotropic hormone (ACTH) challenge. Subjects included 190 infant rhesus macaques (Macaca mulatta – 84 males and 106 females; 118 LL, 60 Ls, and 12 ss subjects), obtaining two blood plasma samples during the stress of separation from their mothers. Then on the following day, we obtained a blood sample following a dexamethasone test, and later that day we obtained a blood sample after an ACTH challenge test. Subjects ranged in age between 90 and 128 days, with a mean age of 107 days. Results Subjects homozygous for the short allele had significantly higher levels of cortisol across all test conditions, when compared to those homozygous for the long allele, or those heterozygous with Ls alleles. Subsequent analyses showed a high correlation between individual cortisol

  16. Overview of ACE-Asia Spring 2001 Investigations on Aerosol Radiative Effects and Related Aerosol Properties

    NASA Technical Reports Server (NTRS)

    Russell, Philip B.; Valero, F. P. J.; Flatau, P. J.; Bergin, M.; Holben, B.; Nakajima, T.; Pilewskie, P.; Bergstrom, R.; Hipskind, R. Stephen (Technical Monitor)

    2001-01-01

    A primary, ACE-Asia objective was to quantify the interactions between aerosols and radiation in the Asia-Pacific region. Toward this end, radiometric and related aerosol measurements were made from ocean, land, air and space platforms. Models that predict aerosol fields guided the measurements and are helping integrate and interpret results. Companion overview's survey these measurement and modeling components. Here we illustrate how these components were combined to determine aerosol radiative. impacts and their relation to aerosol properties. Because clouds can obscure or change aerosol direct radiative effects, aircraft and ship sorties to measure these effects depended on predicting and finding cloud-free areas and times with interesting aerosols present. Pre-experiment satellite cloud climatologies, pre-flight aerosol and cloud forecasts, and in-flight guidance from satellite imagery all helped achieve this. Assessments of aerosol regional radiative impacts benefit from the spatiotemporal coverage of satellites, provided satellite-retrieved aerosol properties are accurate. Therefore, ACE-Asia included satellite retrieval tests, as part of many comparisons to judge the consistency (closure) among, diverse measurements. Early results include: (1) Solar spectrally resolved and broadband irradiances and optical depth measurements from the C-130 aircraft and at Kosan, Korea yielded aerosol radiative forcing efficiencies, permitting comparisons between efficiencies of ACE-Asia and INDOEX aerosols, and between dust and "pollution" aerosols. Detailed results will be presented in separate papers. (2) Based on measurements of wavelength dependent aerosol optical depth (AOD) and single scattering albedo the estimated 24-h a average aerosol radiative forcing efficiency at the surface for photosynthetically active radiation (400 - 700 nm) in Yulin, China is approx. 30 W sq m per AOD(500 nm). (3) The R/V Brown cruise from Honolulu to Sea of Japan sampled an aerosol optical

  17. LES of Laminar-to-Turbulent Particle-Fluid Dynamics in Human and Nonhuman Primate Airways: Applications to Aerosolized Drug Delivery Animal Testing

    NASA Astrophysics Data System (ADS)

    Geisler, Taylor; Padhy, Sourav; Shaqfeh, Eric; Iaccarino, Gianluca

    2016-11-01

    Both the human health benefit and risk from the inhalation of aerosolized medications is often predicted by extrapolating experimental data taken using nonhuman primates to human inhalation. In this study, we employ Large Eddy Simulation to simulate particle-fluid dynamics in realistic upper airway models of both humans and rhesus monkeys. We report laminar-to-turbulent flow transitions triggered by constrictions in the upper trachea and the persistence of unsteadiness into the low Reynolds number bifurcating lower airway. Micro-particle deposition fraction and locations are shown to depend significantly on particle size. In particular, particle filtration in the nasal airways is shown to approach unity for large aerosols (8 microns) or high-rate breathing. We validate the accuracy of LES mean flow predictions using MRV imaging results. Additionally, particle deposition fractions are validated against experiments in 3 model airways.

  18. Aerosol retrieval experiments in the ESA Aerosol_cci project

    NASA Astrophysics Data System (ADS)

    Holzer-Popp, T.; de Leeuw, G.; Griesfeller, J.; Martynenko, D.; Klüser, L.; Bevan, S.; Davies, W.; Ducos, F.; Deuzé, J. L.; Graigner, R. G.; Heckel, A.; von Hoyningen-Hüne, W.; Kolmonen, P.; Litvinov, P.; North, P.; Poulsen, C. A.; Ramon, D.; Siddans, R.; Sogacheva, L.; Tanre, D.; Thomas, G. E.; Vountas, M.; Descloitres, J.; Griesfeller, J.; Kinne, S.; Schulz, M.; Pinnock, S.

    2013-08-01

    Within the ESA Climate Change Initiative (CCI) project Aerosol_cci (2010-2013), algorithms for the production of long-term total column aerosol optical depth (AOD) datasets from European Earth Observation sensors are developed. Starting with eight existing pre-cursor algorithms three analysis steps are conducted to improve and qualify the algorithms: (1) a series of experiments applied to one month of global data to understand several major sensitivities to assumptions needed due to the ill-posed nature of the underlying inversion problem, (2) a round robin exercise of "best" versions of each of these algorithms (defined using the step 1 outcome) applied to four months of global data to identify mature algorithms, and (3) a comprehensive validation exercise applied to one complete year of global data produced by the algorithms selected as mature based on the round robin exercise. The algorithms tested included four using AATSR, three using MERIS and one using PARASOL. This paper summarizes the first step. Three experiments were conducted to assess the potential impact of major assumptions in the various aerosol retrieval algorithms. In the first experiment a common set of four aerosol components was used to provide all algorithms with the same assumptions. The second experiment introduced an aerosol property climatology, derived from a combination of model and sun photometer observations, as a priori information in the retrievals on the occurrence of the common aerosol components. The third experiment assessed the impact of using a common nadir cloud mask for AATSR and MERIS algorithms in order to characterize the sensitivity to remaining cloud contamination in the retrievals against the baseline dataset versions. The impact of the algorithm changes was assessed for one month (September 2008) of data: qualitatively by inspection of monthly mean AOD maps and quantitatively by comparing daily gridded satellite data against daily averaged AERONET sun photometer

  19. iPads at Field Camp: A First Test of the Challenges and Opportunities

    NASA Astrophysics Data System (ADS)

    Hurst, S. D.; Stewart, M. A.

    2011-12-01

    traditional tools. We are addressing some aspects of software limitations and future technology improvements by the industry will naturally reduce other limitations. We will continue testing iPads during field trips and courses for the foreseeable future. As we begin to deal with these limitations and students become more accustomed to their use in the field, we expect our students to more fully embrace iPads as a convenient field and mapping tool.

  20. GCM Simulations of the Aerosol Indirect Effect: Sensitivity to Cloud Parameterization and Aerosol Burden

    NASA Technical Reports Server (NTRS)

    Menon, Surabi; DelGenio, Anthony D.; Koch, Dorothy; Tselioudis, George; Hansen, James E. (Technical Monitor)

    2001-01-01

    We describe the coupling of the Goddard Institute for Space Studies (GISS) general circulation model (GCM) to an online sulfur chemistry model and source models for organic matter and sea-salt that is used to estimate the aerosol indirect effect. The cloud droplet number concentration is diagnosed empirically from field experiment datasets over land and ocean that observe droplet number and all three aerosol types simultaneously; corrections are made for implied variations in cloud turbulence levels. The resulting cloud droplet number is used to calculate variations in droplet effective radius, which in turn allows us to predict aerosol effects on cloud optical thickness and microphysical process rates. We calculate the aerosol indirect effect by differencing the top-of-the-atmosphere net cloud radiative forcing for simulations with present-day vs. pre-industrial emissions. Both the first (radiative) and second (microphysical) indirect effects are explored. We test the sensitivity of our results to cloud parameterization assumptions that control the vertical distribution of cloud occurrence, the autoconversion rate, and the aerosol scavenging rate, each of which feeds back significantly on the model aerosol burden. The global mean aerosol indirect effect for all three aerosol types ranges from -1.55 to -4.36 W m(exp -2) in our simulations. The results are quite sensitive to the pre-industrial background aerosol burden, with low pre-industrial burdens giving strong indirect effects, and to a lesser extent to the anthropogenic aerosol burden, with large burdens giving somewhat larger indirect effects. Because of this dependence on the background aerosol, model diagnostics such as albedo-particle size correlations and column cloud susceptibility, for which satellite validation products are available, are not good predictors of the resulting indirect effect.

  1. Anthropogenic Aerosol Effects on Sea Surface Temperatures: Mixed-Layer Ocean Experiments with Explicit Aerosol Representation

    NASA Astrophysics Data System (ADS)

    Dallafior, Tanja; Folini, Doris; Wild, Martin; Knutti, Reto

    2014-05-01

    Anthropogenic aerosols affect the Earth's radiative balance both through direct and indirect effects. These effects can lead to a reduction of the incoming solar radiation at the surface, i.e. dimming, which may lead to a change in sea surface temperatures (SST) or SST pattern. This, in turn, may affect precipitation patterns. The goal of the present work is to achieve an estimate of the equilibrium SST changes under anthropogenic aerosol forcing since industrialisation. We show preliminary results from mixed-layer ocean (MLO) experiments with explicit aerosol representation performed with ECHAM6-HAM. The (fixed) MLO heat flux into the deep ocean was derived from atmosphere only runs with fixed climatological SSTs (1961-1990 average) and present day (year 2000) aerosols and GHG burdens. Some experiments we repeated with an alternative MLO deep ocean heat flux (based on pre-industrial conditions) to test the robustness of our results with regard to this boundary condition. The maximum surface temperature responses towards anthropogenic aerosol and GHG forcing (separately and combined) were derived on a global and regional scale. The same set of experiments was performed with aerosol and GHG forcings representative of different decades over the past one and a half centuries. This allows to assess how SST patterns at equilibrium changed with changing aerosol (and GHG) forcing. Correlating SST responses with the change in downward clear-sky and all-sky shortwave radiation provides a first estimate of the response to anthropogenic aerosols. Our results show a clear contrast in hemispheric surface temperature response, as expected from the inter-hemispheric asymmetry of aerosol forcing The presented work is part of a project aiming at quantifying the effect of anthropogenic aerosol forcing on SSTs and the consequences for global precipitation patterns. Results from this study will serve as a starting point for further experiments involving a dynamic ocean model, which

  2. GCM Simulations of the Aerosol Indirect Effect: Sensitivity to Cloud Parameterization and Aerosol Burden

    NASA Technical Reports Server (NTRS)

    Menon, Surabi; DelGenio, Anthony D.; Koch, Dorothy; Tselioudis, George; Hansen, James E. (Technical Monitor)

    2001-01-01

    We describe the coupling of the Goddard Institute for Space Studies (GISS) general circulation model (GCM) to an online sulfur chemistry model and source models for organic matter and sea-salt that is used to estimate the aerosol indirect effect. The cloud droplet number concentration is diagnosed empirically from field experiment datasets over land and ocean that observe droplet number and all three aerosol types simultaneously; corrections are made for implied variations in cloud turbulence levels. The resulting cloud droplet number is used to calculate variations in droplet effective radius, which in turn allows us to predict aerosol effects on cloud optical thickness and microphysical process rates. We calculate the aerosol indirect effect by differencing the top-of-the-atmosphere net cloud radiative forcing for simulations with present-day vs. pre-industrial emissions. Both the first (radiative) and second (microphysical) indirect effects are explored. We test the sensitivity of our results to cloud parameterization assumptions that control the vertical distribution of cloud occurrence, the autoconversion rate, and the aerosol scavenging rate, each of which feeds back significantly on the model aerosol burden. The global mean aerosol indirect effect for all three aerosol types ranges from -1.55 to -4.36 W/sq m in our simulations. The results are quite sensitive to the pre-industrial background aerosol burden, with low pre-industrial burdens giving strong indirect effects, and to a lesser extent to the anthropogenic aerosol burden, with large burdens giving somewhat larger indirect effects. Because of this dependence on the background aerosol, model diagnostics such as albedo-particle size correlations and column cloud susceptibility, for which satellite validation products are available, are not good predictors of the resulting indirect effect.

  3. Condensing Organic Aerosols in a Microphysical Model

    NASA Astrophysics Data System (ADS)

    Gao, Y.; Tsigaridis, K.; Bauer, S.

    2015-12-01

    The condensation of organic aerosols is represented in a newly developed box-model scheme, where its effect on the growth and composition of particles are examined. We implemented the volatility-basis set (VBS) framework into the aerosol mixing state resolving microphysical scheme Multiconfiguration Aerosol TRacker of mIXing state (MATRIX). This new scheme is unique and advances the representation of organic aerosols in models in that, contrary to the traditional treatment of organic aerosols as non-volatile in most climate models and in the original version of MATRIX, this new scheme treats them as semi-volatile. Such treatment is important because low-volatility organics contribute significantly to the growth of particles. The new scheme includes several classes of semi-volatile organic compounds from the VBS framework that can partition among aerosol populations in MATRIX, thus representing the growth of particles via condensation of low volatility organic vapors. Results from test cases representing Mexico City and a Finish forrest condistions show good representation of the time evolutions of concentration for VBS species in the gas phase and in the condensed particulate phase. Emitted semi-volatile primary organic aerosols evaporate almost completely in the high volatile range, and they condense more efficiently in the low volatility range.

  4. Ultrasonic/sonic gopher for subsurface ice and brine sampling: analysis and fabrication challenges and testing results

    NASA Astrophysics Data System (ADS)

    Badescu, M.; Sherrit, S.; Olorunsola, A.; Aldrich, J.; Bao, X.; Bar-Cohen, Y.; Chang, Z.; Doran, P. T.; Fritsen, C. H.; Kenig, F.; McKay, C. P.; Murray, A.; Du, S.; Peterson, T.; Song, T.

    2006-03-01

    Rock, soil, and ice penetration by coring, drilling or abrading is of great importance to a large number of space and earth applications. Proven techniques to sample Mars subsurface will be critical for future NASA astrobiology missions that will search for records of past and present life on the planet. An Ultrasonic/Sonic Drill/Corer (USDC) has been developed as an adaptable tool for many of these applications [Bar-Cohen et al., 2001]. The USDC uses a novel drive mechanism to transform the ultrasonic or sonic vibrations of the tip of a horn into a sonic hammering of a drill bit through an intermediate free-flying mass. The USDC design was modified to fabricate an Ultrasonic/Sonic Ice Gopher that is designed to core down to meters depth for in situ analysis and sample collection. This technology was demonstrated at Lake Vida in the Dry Valleys, Antarctica. Coring ice at -20°C as in Lake Vida has been a challenge and efforts were made to develop the required ice core cutting, ice chip handling and potential ice melting (and refreezing) during drilling. The analysis and fabrication challenges and testing results are presented in this paper.

  5. Scale-up of Routine Viral Load Testing in Resource-Poor Settings: Current and Future Implementation Challenges

    PubMed Central

    Roberts, Teri; Cohn, Jennifer; Bonner, Kimberly; Hargreaves, Sally

    2016-01-01

    Despite immense progress in antiretroviral therapy (ART) scale-up, many people still lack access to basic standards of care, with our ability to meet the Joint United Nations Programme on HIV/AIDS 90-90-90 treatment targets for HIV/AIDS dependent on dramatic improvements in diagnostics. The World Health Organization recommends routine monitoring of ART effectiveness using viral load (VL) testing at 6 months and every 12 months, to monitor treatment adherence and minimize failure, and will publish its VL toolkit later this year. However, the cost and complexity of VL is preventing scale-up beyond developed countries and there is a lack of awareness among clinicians as to the long-term patient benefits and its role in prolonging the longevity of treatment programs. With developments in this diagnostic field rapidly evolving—including the recent improvements for accurately using dried blood spots and the imminent appearance to the market of point-of-care technologies offering decentralized diagnosis—we describe current barriers to VL testing in resource-limited settings. Effective scale-up can be achieved through health system and laboratory system strengthening and test price reductions, as well as tackling multiple programmatic and funding challenges. PMID:26743094

  6. Antimicrobial activity of zinc oxide particles on five micro-organisms of the Challenge Tests related to their physicochemical properties.

    PubMed

    Pasquet, Julia; Chevalier, Yves; Couval, Emmanuelle; Bouvier, Dominique; Noizet, Gaëlle; Morlière, Cécile; Bolzinger, Marie-Alexandrine

    2014-01-02

    Zinc oxide is commonly used in pharmaceutical products to prevent or treat topical or systemic diseases owing to its antimicrobial properties, but it is scarcely used as preservative in topical formulations. The aim of this work was to investigate the antimicrobial activity of zinc oxide (ZnO) powders on the five microbial strains used for Challenge Tests in order to evaluate this inorganic compound as a preservative in topical formulation and assess relationships between the structural parameters of ZnO particles and their antimicrobial activity. For this purpose, the physicochemical characteristics of three ZnO grades were measured and their antimicrobial efficacy against the following micro-organisms - Escherichia coli; Staphylococcus aureus; Pseudomonas aeruginosa; Candida albicans; Aspergillus brasiliensis - was assessed using disc diffusion susceptibility tests and a broth dilution method. The comprehensive dataset of physicochemical characteristics and antimicrobial activities (MIC and MBC) is discussed regarding methodological issues related to the particulate nature of ZnO and structure-activity relationships. Every ZnO grade showed bactericidal and antifungal activity against the five tested micro-organisms in a concentration dependent manner. ZnO particles with smaller size, larger specific area and higher porosity exhibit higher antimicrobial activity. Such trends are related to their mechanisms of antimicrobial activity.

  7. [Selection of drugs suitable for the treatment of intractable chronic pain patients by using drug challenge tests].

    PubMed

    Hanaoka, Kazuo; Arita, Hideko; Nagase, Masaki; Ide, Yasuo; Tagami, Megumi; Hayashida, Masakazu

    2008-05-01

    Intractable chronic pain is very difficult to treat. Nowadays, small amounts of drugs, that have different actions on the mechanism of pain relief are administered intravenously, and the effects of the test drugs on individual chronic pain patients are investigated by using the evaluation method of the visual analogue scale (VAS). This will enable elucidation of the mechanisms of pain in each chronic pain patient. Based on this information, drugs that are effective for the treatment of individual chronic pain patients can be prescribed. Drugs that are used for the drug challenge tests are phentolamine, barbiturate, morphine, lidocaine, ketamine, benzodiazepine, adenosine-3-phosphate (ATP), neurotropine, and prostaglandine E1. Phentolamine is effective for the management of sympathetically maintained pain. Barbiturate and morphine are effective for the treatment of deafferentation pain and nociceptive pain, respectively. Lidocaine is effective for the treatment of neuropathic pain; ketamine, for allodynia; and benzodiazepine, for anxiety-related pain. ATP exerts a positive effect in total pain management. Neurotropine and prostaglandine E1 are effective for the management of neuropathic pain and ischemic pain, respectively. These tests aid in the selection of drugs that maybe useful for the treatment of intractable chronic pain in patients.

  8. Coordinating research and practice: challenges testing messages to increase medical reserve corps participation in local health department activities.

    PubMed

    Klaiman, Tamar; Higdon, Melissa; Galarce, Ezequiel

    2013-04-01

    Local health departments (LHDs) increasingly depend on volunteers, often Medical Reserve Corps (MRC) volunteers, to assist with a variety of functions. While LHDs have extensive lists of volunteers, only about 10 % are actively involved in LHD activities. Psychological literature has shown that well-designed messages can motivate behavior among individuals. Key to this theory is the concept of "framing," defined as the influence the characterization of an issue can have on its understanding. Research has been conducted on how to frame and disseminate both political and public health messages to alter individual behavior. We aimed to design and test appropriate evidence-based messages to increase volunteer participation rates in LHD flu clinics. After inviting over 900 MRC units to participate during the 2011-2012 influenza season, five were able to collect and report data to the research team. Using a randomized trial design, we tested messages among the five participating MRC units consisting of a total of 2,020 volunteers. Chi Square analysis showed no difference in attendance between those who received either of the test messages versus the control message (p = .305). Our small sample size of MRC units likely biased our sample and reduced the external validity of our study. Our experience in conducting research with MRC coordinators and volunteers highlights the challenges of conducting research with practitioners who lack the time, infrastructure and resources necessary to work with researchers. There is a strong need for more supportive infrastructure for conducting research with practitioners.

  9. Virus removal retention challenge tests performed at lab scale and pilot scale during operation of membrane units.

    PubMed

    Humbert, H; Machinal, C; Labaye, Ivan; Schrotter, J C

    2011-01-01

    The determination of the virus retention capabilities of UF units during operation is essential for the operators of drinking water treatment facilities in order to guarantee an efficient and stable removal of viruses through time. In previous studies, an effective method (MS2-phage challenge tests) was developed by the Water Research Center of Veolia Environnement for the measurement of the virus retention rates (Log Removal Rate, LRV) of commercially available hollow fiber membranes at lab scale. In the present work, the protocol for monitoring membrane performance was transferred from lab scale to pilot scale. Membrane performances were evaluated during pilot trial and compared to the results obtained at lab scale with fibers taken from the pilot plant modules. PFU culture method was compared to RT-PCR method for the calculation of LRV in both cases. Preliminary tests at lab scale showed that both methods can be used interchangeably. For tests conducted on virgin membrane, a good consistency was observed between lab and pilot scale results with the two analytical methods used. This work intends to show that a reliable determination of the membranes performances based on RT-PCR analytical method can be achieved during the operation of the UF units.

  10. Study of the Population Dynamics of Listeria Monocytogenes and Pseudomonas Fluorescens in Buffalo Mozzarella by Means of Challenge Testing.

    PubMed

    Nava, Donatella; Capo, Salvatore; Caligiuri, Vincenzo; Giaccone, Valerio; Biondi, Loredana; Vaccaro, Gerardo Francesco; Guarino, Achille; Capuano, Federico

    2016-06-03

    Campania's buffalo mozzarella is a greatly appreciated cheese in Italy and worldwide. From a microbiological standpoint, it is a highly perishable food and potentially at risk of contamination by pathogens such as Listeria monocytogenes (L. monocytogenes). The present paper reports the results of a challenge test carried out to assess the population dynamics of L. monocytogenes, alone and in presence of Pseudomonas fluorescens (P. fluorescens), in buffalo mozzarella. For this purpose buffalo mozzarella samples were contaminated with L. monocytogenes alone or combined with P. fluorescens. In samples where L. monocytogenes was inoculated alone, the bacterial load remained unchanged. On the contrary, in samples contaminated with L. monocytogenes and P. fluorescens, the growth of L. monocytogenes increased.

  11. Study of the Population Dynamics of Listeria Monocytogenes and Pseudomonas Fluorescens in Buffalo Mozzarella by Means of Challenge Testing

    PubMed Central

    Nava, Donatella; Capo, Salvatore; Caligiuri, Vincenzo; Giaccone, Valerio; Biondi, Loredana; Vaccaro, Gerardo Francesco; Guarino, Achille; Capuano, Federico

    2016-01-01

    Campania’s buffalo mozzarella is a greatly appreciated cheese in Italy and worldwide. From a microbiological standpoint, it is a highly perishable food and potentially at risk of contamination by pathogens such as Listeria monocytogenes (L. monocytogenes). The present paper reports the results of a challenge test carried out to assess the population dynamics of L. monocytogenes, alone and in presence of Pseudomonas fluorescens (P. fluorescens), in buffalo mozzarella. For this purpose buffalo mozzarella samples were contaminated with L. monocytogenes alone or combined with P. fluorescens. In samples where L. monocytogenes was inoculated alone, the bacterial load remained unchanged. On the contrary, in samples contaminated with L. monocytogenes and P. fluorescens, the growth of L. monocytogenes increased. PMID:27853707

  12. Evaluating Aerosol Process Modules within the Framework of the Aerosol Modeling Testbed

    NASA Astrophysics Data System (ADS)

    Fast, J. D.; Velu, V.; Gustafson, W. I.; Chapman, E.; Easter, R. C.; Shrivastava, M.; Singh, B.

    2012-12-01

    Factors that influence predictions of aerosol direct and indirect forcing, such as aerosol mass, composition, size distribution, hygroscopicity, and optical properties, still contain large uncertainties in both regional and global models. New aerosol treatments are usually implemented into a 3-D atmospheric model and evaluated using a limited number of measurements from a specific case study. Under this modeling paradigm, the performance and computational efficiency of several treatments for a specific aerosol process cannot be adequately quantified because many other processes among various modeling studies (e.g. grid configuration, meteorology, emission rates) are different as well. The scientific community needs to know the advantages and disadvantages of specific aerosol treatments when the meteorology, chemistry, and other aerosol processes are identical in order to reduce the uncertainties associated with aerosols predictions. To address these issues, an Aerosol Modeling Testbed (AMT) has been developed that systematically and objectively evaluates new aerosol treatments for use in regional and global models. The AMT consists of the modular Weather Research and Forecasting (WRF) model, a series testbed cases for which extensive in situ and remote sensing measurements of meteorological, trace gas, and aerosol properties are available, and a suite of tools to evaluate the performance of meteorological, chemical, aerosol process modules. WRF contains various parameterizations of meteorological, chemical, and aerosol processes and includes interactive aerosol-cloud-radiation treatments similar to those employed by climate models. In addition, the physics suite from the Community Atmosphere Model version 5 (CAM5) have also been ported to WRF so that they can be tested at various spatial scales and compared directly with field campaign data and other parameterizations commonly used by the mesoscale modeling community. Data from several campaigns, including the 2006

  13. Challenging Pneumatic Requirements for Acoustic Testing of the Cryogenic Second Stage for the New Delta 3 Rocket

    NASA Technical Reports Server (NTRS)

    Webb, Andrew T.

    1998-01-01

    The paper describes the unique pneumatic test requirements for the acoustic and shock separation testing of the Second Stage for the new Delta III Rocket at the Goddard Space Flight Center in Greenbelt, Maryland. The testing was conducted in the 45,000 cu ft (25-feet wide by 30-feet deep by 50-foot high) Acoustic Facility. The acoustic testing required that the liquid oxygen (LOX) and liquid hydrogen (LH2) tanks be filled with enough liquid nitrogen (LN2) to simulate launch fuel masses during testing. The challenge for this test dealt with designing, procuring, and fabricating the pneumatic supply systems for quick assembly while maintaining the purity requirements and minimizing costs. The pneumatic systems were designed to fill and drain the both LOX and LH2 tanks as well as to operate the fill/drain and vent valves for each of the tanks. The test criteria for the pneumatic sub-systems consisted of function, cleanliness, availability, and cost. The first criteria, function, required the tanks to be filled and drained in an efficient manner while preventing them from seeing pressures greater than 9 psig which would add a pressure cycle to the tank. An LN2 tanker, borrowed from another NASA facility, served as the pre-cool and drain tanker. Pre-cooling the tanks allowed for more efficient and cost effective transfer from the LN2 delivery tankers. Helium gas, supplied from a high purity tube trailer, was used to pressurize the vapor space above the LN2 pushing it into the drain tanker. The tube trailer also supplied high pressure helium to the vehicle for valve control and component purges. Cleanliness was maintained by proper component selection, end-use particle filtration, and any on-site cleaning determined necessary by testing. In order to meet the availability/cost juggling act, products designed for LOX delivery systems were procured to ensure system compatibility while off the shelf valves and tubing designed for the semiconductor industry were procured for

  14. Effect of Aerosol Size and Hygroscopicity on Aerosol Optical Depth in the Southeastern United States

    NASA Astrophysics Data System (ADS)

    Brock, Charles; Wagner, Nick; Gordon, Timothy

    2016-04-01

    Aerosol optical depth (AOD) is affected by the size, optical characteristics, and hygroscopicity of particles, confounding attempts to link remote sensing observations of AOD to measured or modeled aerosol mass concentrations. In situ airborne observations of aerosol optical, chemical, microphysical and hygroscopic properties were made in the southeastern United States in the daytime in summer 2013. We use these observations to constrain a simple model that is used to test the sensitivity of AOD to the various measured parameters. As expected, the AOD was found to be most sensitive to aerosol mass concentration and to aerosol water content, which is controlled by aerosol hygroscopicity and the ambient relative humidity. However, AOD was also fairly sensitive to the mean particle diameter and the width of the size distribution. These parameters are often prescribed in global models that use simplified modal parameterizations to describe the aerosol, suggesting that the values chosen could substantially bias the calculated relationship between aerosol mass and optical extinction, AOD, and radiative forcing.

  15. Unified Aerosol Microphysics for NWP

    DTIC Science & Technology

    2012-09-30

    prediction is now integrated, for example, with the COAMPS two- moment cloud microphysics scheme where it serves as a source of cloud droplet nuclei. The dust ...behavior. To evaluate the new handling of aerosol dust and its interaction with COAMPS microphysics, an operational test case has been developed...Sahara Air Layer (SAL) and Hurricane Nadine off of West Africa. Dust is seen wrapping around the north side of the storm on Sep 11 in Figure 2. We

  16. Overview of Aerosol Distribution

    NASA Technical Reports Server (NTRS)

    Kaufman, Yoram

    2005-01-01

    Our knowledge of atmospheric aerosols (smoke, pollution, dust or sea salt particles, small enough to be suspended in the air), their evolution, composition, variability in space and time and interaction with clouds and precipitation is still lacking despite decades of research. Understanding the global aerosol system is fundamental for progress in climate change and hydrological cycle research. While a single instrument was used to demonstrate 50 years ago that the global CO2 levels are rising, posing threat of global warming, we need an array of satellites and field measurements coupled with chemical transport models to understand the global aerosol system. This complexity of the aerosol problem results from their short lifetime (1 week) and variable chemical composition. A new generation of satellites provides exciting opportunities to measure the global distribution of aerosols, distinguishing natural from anthropogenic aerosol and measuring their interaction with clouds and climate. I shall discuss these topics and application of the data to air quality monitoring.

  17. Rewards and challenges of providing HIV testing and counselling services: health worker perspectives from Burkina Faso, Kenya and Uganda.

    PubMed

    Bott, Sarah; Neuman, Melissa; Helleringer, Stephane; Desclaux, Alice; Asmar, Khalil El; Obermeyer, Carla Makhlouf

    2015-10-01

    The rapid scale-up of human immunodeficiency virus (HIV) testing, counselling and treatment throughout sub-Saharan Africa has raised questions about how to protect patients' rights to consent, confidentiality, counselling and care in resource-constrained settings. The Multi-country African Testing and Counselling for HIV (MATCH) study investigated client and provider experiences with different modes of testing in sub-Saharan Africa. One component of that study was a survey of 275 HIV service providers in Burkina Faso, Kenya and Uganda that gathered quantifiable indicators and qualitative descriptions using a standardized instrument. This article presents provider perspectives on the challenges of obtaining consent, protecting confidentiality, providing counselling and helping clients manage disclosure. It also explores health workers' fear of infection within the workplace and their reports on discrimination against HIV clients within health facilities. HIV care providers in Burkina Faso, Kenya and Uganda experienced substantial rewards from their work, including satisfaction from saving lives and gaining professional skills. They also faced serious resource constraints, including staff shortages, high workloads, lack of supplies and inadequate infrastructure, and they expressed concerns about accidental exposure. Health workers described heavy emotional demands from observing clients suffer emotional, social and health consequences of being diagnosed with HIV, and also from difficult ethical dilemmas related to clients who do not disclose their HIV status to those around them, including partners. These findings suggest that providers of HIV testing and counselling need more resources and support, including better protections against HIV exposure in the workplace. The findings also suggest that health facilities could improve care by increasing attention to consent, privacy and confidentiality and that health policy makers and ethicists need to address some

  18. The Challenge of Producing Skin Test Antigens with Minimal Resources Suitable for Human Application against a Neglected Tropical Disease; Leprosy

    PubMed Central

    Rivoire, Becky L.; TerLouw, Stephen; Groathouse, Nathan A.; Brennan, Patrick J.

    2014-01-01

    True incidence of leprosy and its impact on transmission will not be understood until a tool is available to measure pre-symptomatic infection. Diagnosis of leprosy disease is currently based on clinical symptoms, which on average take 3–10 years to manifest. The fact that incidence, as defined by new case detection, equates with prevalence, i.e., registered cases, suggests that the cycle of transmission has not been fully intercepted by implementation of multiple drug therapy. This is supported by a high incidence of childhood leprosy. Epidemiological screening for pre-symptomatic leprosy in large endemic populations is required to facilitate targeted chemoprophylactic interventions. Such a test must be sensitive, specific, simple to administer, cost-effective, and easy to interpret. The intradermal skin test method that measures cell-mediated immunity was explored as the best option. Prior knowledge on skin testing of healthy subjects and leprosy patients with whole or partially fractionated Mycobacterium leprae bacilli, such as Lepromin or the Rees' or Convit' antigens, has established an acceptable safety and potency profile of these antigens. These data, along with immunoreactivity data, laid the foundation for two new leprosy skin test antigens, MLSA-LAM (M. leprae soluble antigen devoid of mycobacterial lipoglycans, primarily lipoarabinomannan) and MLCwA (M. leprae cell wall antigens). In the absence of commercial interest, the challenge was to develop these antigens under current good manufacturing practices in an acceptable local pilot facility and submit an Investigational New Drug to the Food and Drug Administration to allow a first-in-human phase I clinical trial. PMID:24874086

  19. Domestic Preparedness Program: Phase 2 Sarin (GB) and Distilled Sulfur Mustard (HD) Vapor Challenge Testing of Commercial Self-Contained Breathing Apparatus Facepieces

    DTIC Science & Technology

    2005-03-01

    GB Mustard HD Self-Contained Breathing Apparatus Sarin Chemical Agent Breakthrough SCBA Agent Challenge Testing ...emergency escape breathing apparatus. 3. CHEMICAL AGENT TESTING 3.1 Chemical Agent Testing Equipment. 3.1.1 Vapor Generator. The GB and HD vapors were... agent seeped inside the other two within 4 min. For all three tests , the North Model 821 resisted HD for 60 min and GB for 25, 28, and 32 min.

  20. Aerosol, radiation, and climate

    NASA Technical Reports Server (NTRS)

    Pollack, J. B.

    1983-01-01

    Airborne, spaceborne, and ground-based measurements are used to study the radiative and climatic effects of aerosols. The data, which are modelled with a hierarchy of radiation and climate models, and their implications are summarized. Consideration is given to volcanic aerosols, polar stratospheric clouds, and the Arctic haze. It is shown that several types of aerosols (volcanic particles and the Arctic haze) cause significant alterations to the radiation budget of the regions where they are located.

  1. Influence of Aerosols on Monsoon Circulation and Hydroclimate

    NASA Technical Reports Server (NTRS)

    Lau, William K.

    2006-01-01

    Long recognized as a major environmental hazard, aerosol is now known to have strong impacts on both regional and global water cycles and climate change. In the Asian monsoon regions, the response of the regional water cycle and climate to aerosol forcing is very complex, not only because of presence of diverse mix of aerosol species with vastly different radiative properties, but also because the monsoon is strongly influenced by ocean and land surface processes, land use, land change, as well as regional and global greenhouse warming effects. Thus, sorting out the impacts of aerosol forcing, and interaction with the monsoon water cycle is a very challenging problem. Up to now, besides the general notion that aerosols may significantly impact monsoon through altering large scale radiative heating gradients, there has been very little information regarding the specific signatures, and mechanisms of aerosol-monsoon water cycle interaction. In this talk, based on preliminary results from observations and climate model experiments, I will offer some insights into how aerosols may impact the Asian monsoon water cycle, in particular the effects of absorbing aerosols (dust and black carbon), and the role of the Tibetan Plateau. The influence of aerosol forcing relative to those due to sea surface temperature and land surface processes, and impact on potential predictability of the monsoon climate system will also be discussed.

  2. Influence of Aerosols on Monsoon Circulation and Hydroclimate

    NASA Technical Reports Server (NTRS)

    Lau, William K.M.

    2007-01-01

    Long recognized as a major environmental hazard, aerosol is now known to have strong impacts on both regional and global water cycles and climate change. In the Asian monsoon regions, the response of the regional water cycle and climate to aerosol forcing is very complex, not only because of presence of diverse mix of aerosol species with vastly different radiative properties, but also because the monsoon is strongly influenced by ocean and land surface processes, land use, land change, as well as regional and global greenhouse warming effects. Thus, sorting out the impacts of aerosol forcing, and interaction with the monsoon water cycle is a very challenging problem. Up to now, besides the general notion that aerosols may significantly impact monsoon through altering large scale radiative heating gradients, there has been very little information regarding the specific signatures, and mechanisms of aerosol-monsoon water cycle interaction. In this talk, based on preliminary results from observations and climate model experiments, I will offer some insights into how aerosols may impact the Asian monsoon water cycle, in particular the effects of absorbing aerosols (dust and black carbon), and the role of the Tibetan Plateau. The influence of aerosol forcing relative to those due to sea surface temperature and land surface processes, and impact on potential predictability of the monsoon climate system will also be discussed.

  3. Radiative Effects of Aerosols

    NASA Technical Reports Server (NTRS)

    Valero, Francisco P. J.

    1997-01-01

    During the Atlantic Stratocumulus Transition Experiment (ASTEX) in June 1992, two descents in cloud-free regions allowed comparison of the change in aerosol optical depth as determined by an onboard total-direct-diffuse radiometer (TDDR) to the change calculated from measured size resolved aerosol microphysics and chemistry. Both profiles included pollution haze layer from Europe but the second also included the effect of a Saharan dust layer above the haze. The separate contributions of supermicrometer (coarse) and submicrometer (fine) aerosol were determined and thermal analysis of the pollution haze indicated that the fine aerosol was composed primarily of a sulfate/water mixture with a refractory soot-like core.

  4. Placebo-controlled comparison of three dose-regimens of 5-hydroxytryptophan challenge test in healthy volunteers.

    PubMed

    Gijsman, Harm J; van Gerven, Joop M A; de Kam, Marieke L; Schoemaker, Rik C; Pieters, Monique S M; Weemaes, Margo; de Rijk, Roel; van der Post, Jeroen; Cohen, Adam F

    2002-04-01

    Single-dose administration of 5-hydroxytryptophan (5-HTP) is regularly used as a challenge test of the serotonergic system. The use of 5-HTP has been limited by an apparent small window between the occurrence of neuroendocrine endpoints and the occurrence of side effects. Therefore, many dosing strategies have been tried with and without concurrent administration of carbidopa, a peripheral inhibitor of the decarboxylation from 5-HTP to serotonin. The aim of the current study was to assess the relation between pharmacokinetics and pharmacodynamics of 5-HTP. Twelve healthy male volunteers were included in a placebo-controlled, randomized, four-way crossover, double-blind, single-dose investigation of oral 5-HTP with or without coadministration of carbidopa. The four dose regimens were placebo, 5-HTP 100 mg, 5-HTP 200 mg, and 5-HTP 100 mg with coadministration of carbidopa 100 mg and 50 mg at 3 hours before and 3 hours after the administration of 5-HTP, respectively. The last regimen resulted in a doubling of the elimination half-life, an apparent clearance at least 14 times smaller, and a 15.4 times greater area under the curve compared with 5-HTP 100 mg without carbidopa. Furthermore, it was the only regimen to induce a significant change in cortisol and prolactin. It did not induce any change in subjective psychologic symptoms or cardiovascular parameters, but it was the only regimen to induce some nausea in three participants. The authors conclude that this regimen of 5-HTP 100 mg plus carbidopa is a relatively simple, effective, and tolerable challenge of the presynaptic serotonergic system. Further increase of the dose of 5-HTP might improve the size of the effect on endpoints as long as the tolerability remains good.

  5. An Analysis of AERONET Aerosol Absorption Properties and Classifications Representative of Aerosol Source Regions

    NASA Technical Reports Server (NTRS)

    Giles, David M.; Holben, Brent N.; Eck, Thomas F.; Sinyuk, Aliaksandr; Smirnov, Alexander; Slutsker, Ilya; Dickerson, R. R.; Thompson, A. M.; Schafer, J. S.

    2012-01-01

    Partitioning of mineral dust, pollution, smoke, and mixtures using remote sensing techniques can help improve accuracy of satellite retrievals and assessments of the aerosol radiative impact on climate. Spectral aerosol optical depth (tau) and single scattering albedo (omega (sub 0) ) from Aerosol Robotic Network (AERONET) measurements are used to form absorption [i.e., omega (sub 0) and absorption Angstrom exponent (alpha(sub abs))] and size [i.e., extinction Angstrom exponent (alpha(sub ext)) and fine mode fraction of tau] relationships to infer dominant aerosol types. Using the long-term AERONET data set (1999-2010), 19 sites are grouped by aerosol type based on known source regions to: (1) determine the average omega (sub 0) and alpha(sub abs) at each site (expanding upon previous work); (2) perform a sensitivity study on alpha(sub abs) by varying the spectral omega (sub 0); and (3) test the ability of each absorption and size relationship to distinguish aerosol types. The spectral omega (sub 0) averages indicate slightly more aerosol absorption (i.e., a 0.0 < delta omega (sub 0) <= 0.02 decrease) than in previous work and optical mixtures of pollution and smoke with dust show stronger absorption than dust alone. Frequency distributions of alpha(sub abs) show significant overlap among aerosol type categories and at least 10% of the alpha(sub abs) retrievals in each category are below 1.0. Perturbing the spectral omega (sub 0) by +/- 0.03 induces significant alpha(sub abs) changes from the unperturbed value by at least approx. +/- 0.6 for Dust, approx. +/-0.2 for Mixed, and approx. +/-0.1 for Urban/Industrial and Biomass Burning. The omega (sub 0)440nm and alpha(sub ext) 440-870nm relationship shows the best separation among aerosol type clusters, providing a simple technique for determining aerosol type from surface- and future space-based instrumentation.

  6. Effects of mineral dust on the semivolatile inorganic aerosol components in a polluted Megacity

    NASA Astrophysics Data System (ADS)

    Karydis, V. A.; Tsimpidi, A. P.; Fountoukis, C.; Nenes, A.; Zavala, M.; Lei, W.; Molina, L. T.; Pandis, S. N.

    2009-04-01

    Aerosols play a significant role in the atmosphere having adverse impacts on human health and directly affecting air quality, visibility and climate change. One of the most challenging tasks for models is the prediction of the partitioning of the semivolatile inorganic aerosol components (ammonia, nitric acid, hydrochloric acid, etc) between the gas and particulate phases. Moreover, the effects of mineral aerosols in the atmosphere remain largely uncertain. As a result, most current models have serious difficulties in reproducing the observed particulate nitrate and chloride concentrations. The improved aerosol thermodynamic model ISORROPIA II (Fountoukis and Nenes, 2007) simulating explicitly the chemistry of Ca, Mg, and K salts has been linked to the regional chemical transport model PMCAMx (Gaydos et al., 2007). PMCAMx also includes the CMU inorganic aerosol growth module (Gaydos et al., 2003; Koo et al., 2003a) and the VSRM aqueous-phase chemistry module (Fahey and Pandis, 2001). The hybrid approach (Koo et al., 2003b) for modeling aerosol dynamics is applied in order to accurately simulate the inorganic components in the coarse mode. This approach assumes that the smallest particles are in equilibrium, while the condensation/evaporation equation is solved for the larger ones. PMCAMx is applied to the Mexico City Metropolitan Area (MCMA). The emission inventory has been improved and now includes more accurate dust and NaCl emissions. The April 2003 (MCMA Campaign) and the March 2006 (MILAGRO campaign) datasets are used to evaluate the inorganic aerosol module of PMCAMx in order to test our understanding of inorganic aerosol. The results from the new modeling framework are also compared with the results from the previous version of PMCAMx in order to investigate the influence of each of the added features to the formation of the semivolatile inorganic components. References Fountoukis, C. and Nenes, A., (2007). ISORROPIA II: a computationally efficient

  7. Development and testing of an aerosol/stratus cloud parameterization scheme for middle and high latitudes. Final technical progress report, November 1, 1994--October 31, 1998

    SciTech Connect

    Kreidenweis, S.M.; Cotton, W.R.

    1999-05-20

    At the present time, general circulation models (GCMs) poorly represent clouds, to the extent that they cannot be relied upon to simulate the climatic effects of increasing concentrations of greenhouse gases, or of anthropogenic perturbations to concentrations of cloud condensation nuclei (CCN) or ice nuclei (IN). The long-term objective of this research was the development of an aerosol/cloud microphysics parameterization of mixed-phase stratus and boundary-layer clouds which responds to variations in CCN and IN. The work plan was to perform simulations of these cloud systems to gain understanding of their dynamics and microphysics, especially how aerosols affect cloud development and properties, that cold then be used to guide parameterizations. Several versions of the CSU RAMS (Regional Atmospheric Modeling System), modified to treat Arctic clouds, have been used during the course of this work. The authors also developed a new modeling system, the Trajectory Ensemble Model, to perform detailed chemical and microphysical simulations off-line from the host LES model. The increased understanding of the cloud systems investigated in this research can be applied to a single-column cloud model, designed as an adaptive grid model which can interface into a GCM vertical grid through distinct layers of the troposphere where the presence of layer clouds is expected.

  8. Aerosol penetration through filtering facepieces and respirator cartridges.

    PubMed

    Chen, C C; Lehtimäki, M; Willeke, K

    1992-09-01

    Air-purifying respirators must be certified following the National Institute for Occupational Safety and Health (NIOSH) filter test criteria (30 CFR 11). The criteria specify a range for the mean particle size and the measure of spread permissible for the test aerosol. The authors' experiments have shown that aerosol penetration as a function of particle size differs considerably among certified respirators of the same type. Filtering facepieces (disposable respirators) and cartridges of the dust-mist, dust-mist-fume, and high-efficiency particulate air type were tested. The respirators were sealed to mannequins in a test chamber. The aerosol concentrations inside and outside the respirator were measured by an aerodynamic particle sizer and a laser aerosol spectrometer over a particle size range of 0.1 to 15 microns. Five flow rates ranging from 5 to 100 L/min were used to study flow dependency. The aerosol penetration through the filters is presented as a function of particle size. Aerosol penetration and pressure drop are combined to express the performance of each filter in terms of "quality factor." Under the same test conditions, the quality factor of one respirator may be as much as 6.6 times more than that of another respirator of the same type. The filter quality factor has a greater aerosol size dependency as airflow and aerosol size increase. In general, cartridges have a larger surface area than filtering facepieces but not necessarily lower filter penetration or higher filter quality.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. DMPS (DIMAVAL) as a challenge test to assess the mercury and arsenic body/kidney load in humans and as a treatment of mercury toxicity

    SciTech Connect

    Aposhian, H.V.; Maiorino, R.M.; Aposhian, M.M.; Hurlbut, K.M.

    1996-12-31

    Mercury is an element which, with its compounds, is hazardous and is found in hazardous wastes. In Order to develop suitable diagnostic and therapeutic agents for mercury exposure, we have sought alternative test systems. We have used the chelating agent 2,3-dimercaptopropane-1-sulfonate (DMPS, DIMAVAL{reg_sign}) for estimating the body burden of mercury in normal humans and in dental personnel in a developing country, and for detoxifying humans with mercurous chloride exposure. Use of the DMPS-mercury challenge test has shown that two-thirds of the mercury excreted in the urine of volunteers with dental amalgams appears to be derived from the mercury vapor released from their amalgams. The DMPS challenge test (300 mg, by mouth, after an 11 hr fast) was useful for monitoring dental personnel for mercury vapor exposure. The DMPS challenge test was given to 11 factory workers who make a skin lotion that contains mercurous chloride, 8 users of the skin lotion, and 9 controls. The increases in urinary Hg resulting from the DMPS challenge were 45, 87, and 38-fold, respectively. The results demonstrate that in humans exposed to mercurous chloride, the DMPS-mercury challenge test is of value for a more realistic estimation of mobilizable Hg. DMPS should be considered for use to determine mercury body burdens and to treat humans exposed to mercury and its compounds via exposure to hazardous wastes. 42 refs., 2 figs., 5 tabs.

  10. Direct Aerosol Forcing Uncertainty

    DOE Data Explorer

    Mccomiskey, Allison

    2008-01-15

    Understanding sources of uncertainty in aerosol direct radiative forcing (DRF), the difference in a given radiative flux component with and without aerosol, is essential to quantifying changes in Earth's radiation budget. We examine the uncertainty in DRF due to measurement uncertainty in the quantities on which it depends: aerosol optical depth, single scattering albedo, asymmetry parameter, solar geometry, and surface albedo. Direct radiative forcing at the top of the atmosphere and at the surface as well as sensitivities, the changes in DRF in response to unit changes in individual aerosol or surface properties, are calculated at three locations representing distinct aerosol types and radiative environments. The uncertainty in DRF associated with a given property is computed as the product of the sensitivity and typical measurement uncertainty in the respective aerosol or surface property. Sensitivity and uncertainty values permit estimation of total uncertainty in calculated DRF and identification of properties that most limit accuracy in estimating forcing. Total uncertainties in modeled local diurnally averaged forcing range from 0.2 to 1.3 W m-2 (42 to 20%) depending on location (from tropical to polar sites), solar zenith angle, surface reflectance, aerosol type, and aerosol optical depth. The largest contributor to total uncertainty in DRF is usually single scattering albedo; however decreasing measurement uncertainties for any property would increase accuracy in DRF. Comparison of two radiative transfer models suggests the contribution of modeling error is small compared to the total uncertainty although comparable to uncertainty arising from some individual properties.

  11. Global Aerosol Observations

    Atmospheric Science Data Center

    2013-04-19

    ... atmosphere, directly influencing global climate and human health. Ground-based networks that accurately measure column aerosol amount and ... being used to improve Air Quality Models and for regional health studies. To assess the human-health impact of chronic aerosol exposure, ...

  12. Portable Aerosol Contaminant Extractor

    DOEpatents

    Carlson, Duane C.; DeGange, John J.; Cable-Dunlap, Paula

    2005-11-15

    A compact, portable, aerosol contaminant extractor having ionization and collection sections through which ambient air may be drawn at a nominal rate so that aerosol particles ionized in the ionization section may be collected on charged plate in the collection section, the charged plate being readily removed for analyses of the particles collected thereon.

  13. Ganges valley aerosol experiment.

    SciTech Connect

    Kotamarthi, V.R.; Satheesh, S.K.

    2011-08-01

    In June 2011, the Ganges Valley Aerosol Experiment (GVAX) began in the Ganges Valley region of India. The objective of this field campaign is to obtain measurements of clouds, precipitation, and complex aerosols to study their impact on cloud formation and monsoon activity in the region.

  14. MISR Level 2 Aerosol and Land Versioning

    Atmospheric Science Data Center

    2016-11-04

    ... 3.94E-6 3.94E-6 (unchanged) Add brightness test to aerosol retrieval applicability logic. This should eliminate many cloud ... instead of using a surface contrast threshold, a new test is used which is based on a weighted mean equivalent reflectance ...

  15. Temporal evolution of aerosol derived from N2-Raman lidar at a Mediterranean coastal site

    NASA Astrophysics Data System (ADS)

    Shang, Xiaoxia; Chazette, Patrick; Totems, Julien

    2016-04-01

    Following the temporal variability of the aerosols in the atmospheric column on coastal areas is challenging. In situ ground-based or integrated column properties are not enough to understand the sea-continent exchange processes and identify the sources of particles. Now classical approach using the synergy between passive (e.g. sunphotometer) and active (e.g. backscatter lidar) instruments gives only a partial view of the aerosol properties, because they could be highly heterogeneous in the lower and middle troposphere. On June-July 2014, an automatic N2-Raman lidar (355 nm) was installed at a coastal site close to Toulon in the South of France. Using the coupling between cross-polarized elastic and N2-Raman channels, various aerosol natures are identified all along the time and against the altitude. Specific regularization algorithms have been tested to improve the aerosol classification. The results of these tests will be presented in terms of sensitivity studies based on the Monte Carlo approach. Selecting the most appropriate inversion method of the lidar profiles, the aerosol types encountered during the field campaign will be presented. We will also discuss their origin and the sea-continent exchanges including the sea breeze effect. We will see that a proper identification of particles passes through analyses coupling satellite observations and air mass trajectory studies. Acknowledgments: The experiments have been funded by the Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), the Centre National d'Etudes Spatiales (CNES), and the Centre national de la recherchescientifique (CNRS). We thank Université de Toulon (SeaTech Engineering School) for their hosts. The Institut Pierre Simon Laplace (IPSL), Labex IPSL, is also acknowledged for its support in the data simulations and analyses.

  16. Aerosol fluxes in the marine boundary layer

    NASA Astrophysics Data System (ADS)

    Petelski, Tomasz; Zieliński, Tymon; Makuch, Przemysław; Kowalczyk, Jakub; Ponczkowska, Agnieszka; Drozdowska, Violetta; Piskozub, Jacek

    2010-05-01

    We present aerosol emission fluxes and concentrations calculated from in-situ measurement in the Nordic Sea from R/V Oceania. We compare vertical fluxes calculated with the eddy correlation and gradient methods. We use the results to test the hypothesis that marine aerosol emitted from the sea surface helps to clear the boundary layer from other aerosol particles. As the emitted droplets do not dry out in the highly humid surface layer air and because of their sizes most of them are deposited quickly at the sea surface. Therefore marine aerosol has many features of rain meaning that the deposition in the marine boundary layer in high wind events is controlled not only by the "dry" processes but also by the "wet" scavenging. We have estimated the effectiveness of the process using our own measurements of vertical aerosol fluxes in the Nordic Seas. This process could explain observed phenomenon of lower Arctic aerosol optical thickness (AOT) when the air masses moved over open sea than over sea-ice. We show a negative correlation between the sea-ice coverage in the seas adjacent to Svalbard and monthly AOT values in Ny Alesund.

  17. Total serum IgE level influences oral food challenge tests for IgE-mediated food allergies.

    PubMed

    Horimukai, K; Hayashi, K; Tsumura, Y; Nomura, I; Narita, M; Ohya, Y; Saito, H; Matsumoto, K

    2015-03-01

    Probability curves predicting oral food challenge test (OFC) results based on specific IgE levels are widely used to prevent serious allergic reactions. Although several confounding factors are known to affect probability curves, the main factors that affect OFC outcomes are currently unclear. We hypothesized that an increased total IgE level would reduce allergic reactivity. Medical records of 337 and 266 patients who underwent OFCs for 3.5 g boiled hen's egg white and 3.1 ml raw cow's milk, respectively, were examined retrospectively. We subdivided the patients into three groups based on total IgE levels and age by percentile (<25th, 25-75th, and >75th percentiles), and logistic regression analyses were performed on each group. Patients with higher total IgE levels were significantly less responsive. In addition, age did not significantly affect the OFC results. Therefore, total IgE levels should be taken into account when predicting OFC results based on food-specific IgE levels.

  18. Analytical techniques for ambient sulfate aerosols

    SciTech Connect

    Johnson, S.A.; Graczyk, D.G.; Kumar, R.; Cunningham, P.T.

    1981-06-01

    Work done to further develop the infrared spectroscopic analytical method for the analysis of atmospheric aerosol particles, as well as some exploratory work on a new procedure for determining proton acidity in aerosol samples is described. Earlier work had led to the successful use of infrared (ir) spectrophotometry for the analysis of nitrate, ammonium, and neutral and acidic sulfates in aerosol samples collected by an impactor on a Mylar-film substrate. In this work, a filter-extraction method was developed to prepare filter-collected aerosol samples for ir analysis. A study was made comparing the ir analytical results on filter-collected samples with impactor-collected samples. Also, the infrared analytical technique was compared in field studies with light-scattering techniques for aerosol analysis. A highly sensitive instrument for aerosol analysis using attenuated total internal reflection (ATR) infrared spectroscopy was designed, built, and tested. This instrument provides a measurement sensitivity much greater (by a factor of 6 for SO/sub 4//sup 2 -/) than that obtainable using the KBr-pellet method. This instrument collect size- and time-resolved samples and is potentially capable of providing automated, near real-time aerosol analysis. Exploratory work on a novel approach to the determination of proton acidity in filter- or impactor-collected aerosol samples is also described. In this technique, the acidic sample is reacted with an access of a tagged, vapor-phase base. The unreacted base is flushed off and the amount of the tag retained by the sample is a direct measure of the proton acidity of the sample. The base was tagged with Ge, which can be conveniently determined by the x-ray fluorescence technique.

  19. Radiative Effects of Aerosols

    NASA Technical Reports Server (NTRS)

    Valero, Francisco P. J.

    1996-01-01

    During the Atlantic Stratocumulus Transition Experiment (ASTEX) in June 1992, two descents in cloud-free regions allowed comparison of the change in aerosol optical depth as determined by an onboard total-direct-diffuse radiometer (TDDR) to the change calculated from measured size-resolved aerosol microphysics and chemistry. Both profiles included a pollution haze from Europe but the second also included the effect of a Saharan dust layer above the haze. The separate contributions of supermicrometer (coarse) and submicrometer (fine) aerosol were determined and thermal analysis of the pollution haze indicated that the fine aerosol was composed primarily of a sulfate/water mixture with a refractory soot-like core. The soot core increased the calculated extinction by about 10% in the most polluted drier layer relative to a pure sulfate aerosol but had significantly less effect at higher humidities. A 3 km descent through a boundary layer air mass dominated by pollutant aerosol with relative humidities (RH) 10-77% yielded a close agreement between the measured and calculated aerosol optical depths (550 nm) of 0.160 (+/- 0.07) and 0. 157 (+/- 0.034) respectively. During descent the aerosol mass scattering coefficient per unit sulfate mass varied from about 5 to 16 m(exp 2)/g and primarily dependent upon ambient RH. However, the total scattering coefficient per total fine mass was far less variable at about 4+/- 0.7 m(exp 2)/g. A subsequent descent through a Saharan dust layer located above the pollution aerosol layer revealed that both layers contributed similarly to aerosol optical depth. The scattering per unit mass of the coarse aged dust was estimated at 1.1 +/- 0.2 m(exp 2)/g. The large difference (50%) in measured and calculated optical depth for the dust layer exceeded measurements.

  20. Prevalence and challenge tests of Listeria monocytogenes in Belgian produced and retailed mayonnaise-based deli-salads, cooked meat products and smoked fish between 2005 and 2007.

    PubMed

    Uyttendaele, M; Busschaert, P; Valero, A; Geeraerd, A H; Vermeulen, A; Jacxsens, L; Goh, K K; De Loy, A; Van Impe, J F; Devlieghere, F

    2009-07-31

    Processed ready-to-eat (RTE) foods with a prolonged shelf-life under refrigeration are at risk products for listeriosis. This manuscript provides an overview of prevalence data (n=1974) and challenge tests (n=299) related to Listeria monocytogenes for three categories of RTE food i) mayonnaise-based deli-salads (1187 presence/absence tests and 182 challenge tests), ii) cooked meat products (639 presence/absence tests and 92 challenge tests), and iii) smoked fish (90 presence/absence tests and 25 challenge tests), based on data records obtained from various food business operators in Belgium in the frame of the validation and verification of their HACCP plans over the period 2005-2007. Overall, the prevalence of L. monocytogenes in these RTE foods in the present study was lower compared to former studies in Belgium. For mayonnaise-based deli-salads, in 80 out of 1187 samples (6.7%) the pathogen was detected in 25 g. L. monocytogenes positive samples were often associated with smoked fish deli-salads. Cooked meat products showed a 1.1% (n=639) prevalence of the pathogen. For both food categories, numbers per gram never exceeded 100 CFU. L. monocytogenes was detected in 27.8% (25/90) smoked fish samples, while 4/25 positive samples failed to comply to the 100 CFU/g limit set out in EU Regulation 2073/2005. Challenge testing showed growth potential in 18/182 (9.9%) deli-salads and 61/92 (66%) cooked meat products. Nevertheless, both for deli-salads and cooked meat products, appropriate product formulation and storage conditions based upon hurdle technology could guarantee no growth of L. monocytogenes throughout the shelf-life as specified by the food business operator. Challenge testing of smoked fish showed growth of L. monocytogenes in 12/25 samples stored for 3-4 weeks at 4 degrees C. Of 45 (non-inoculated) smoked fish samples (13 of which were initially positive in 25 g) which were subjected to shelf-life testing, numbers exceeded 100 CFU/g in only one sample

  1. MATRIX-VBS Condensing Organic Aerosols in an Aerosol Microphysics Model

    NASA Technical Reports Server (NTRS)

    Gao, Chloe Y.; Tsigaridis, Konstas; Bauer, Susanne E.

    2015-01-01

    The condensation of organic aerosols is represented in a newly developed box-model scheme, where its effect on the growth and composition of particles are examined. We implemented the volatility-basis set (VBS) framework into the aerosol mixing state resolving microphysical scheme Multiconfiguration Aerosol TRacker of mIXing state (MATRIX). This new scheme is unique and advances the representation of organic aerosols in models in that, contrary to the traditional treatment of organic aerosols as non-volatile in most climate models and in the original version of MATRIX, this new scheme treats them as semi-volatile. Such treatment is important because low-volatility organics contribute significantly to the growth of particles. The new scheme includes several classes of semi-volatile organic compounds from the VBS framework that can partition among aerosol populations in MATRIX, thus representing the growth of particles via condensation of low volatility organic vapors. Results from test cases representing Mexico City and a Finish forrest condistions show good representation of the time evolutions of concentration for VBS species in the gas phase and in the condensed particulate phase. Emitted semi-volatile primary organic aerosols evaporate almost completely in the high volatile range, and they condense more efficiently in the low volatility range.

  2. A Cough Aerosol Simulator for the Study of Disease Transmission by Human Cough-Generated Aerosols

    PubMed Central

    Lindsley, William G.; Reynolds, Jeffrey S.; Szalajda, Jonathan V.; Noti, John D.; Beezhold, Donald H.

    2015-01-01

    Aerosol particles expelled during human coughs are a potential pathway for infectious disease transmission. However, the importance of airborne transmission is unclear for many diseases. To better understand the role of cough aerosol particles in the spread of disease and the efficacy of different types of protective measures, we constructed a cough aerosol simulator that produces a humanlike cough in a controlled environment. The simulated cough has a 4.2 l volume and is based on coughs recorded from influenza patients. In one configuration, the simulator produces a cough aerosol containing particles from 0.1 to 100 µm in diameter with a volume median diameter (VMD) of 8.5 µm and a geometric standard deviation (GSD) of 2.9. In a second configuration, the cough aerosol has a size range of 0.1–30 µm, a VMD of 3.4 µm, and a GSD of 2.3. The total aerosol volume expelled during each cough is 68 µl. By generating a controlled and reproducible artificial cough, the simulator allows us to test different ventilation, disinfection, and personal protection scenarios. The system can be used with live pathogens, including influenza virus, which allows isolation precautions used in the healthcare field to be tested without risk of exposure for workers or patients. The information gained from tests with the simulator will help to better understand the transmission of infectious diseases, develop improved techniques for infection control, and improve safety for healthcare workers and patients. PMID:26500387

  3. Development and testing of an aerosol/stratus cloud parameterization scheme for middle and high latitudes. Year 3 technical progress report, November 1, 1996--August 31, 1997

    SciTech Connect

    Kreidenweis, S.M.; Cotton, W.R.

    1997-09-02

    At the present time, general circulation models (GCMs) poorly represent clouds, to the extent that they cannot be relied upon to simulate the climatic effects of increasing concentrations of greenhouse gases, or of anthropogenic perturbations to concentrations of cloud condensation nuclei (CCN) or ice nuclei (IN). The net radiative forcing of clouds varies strongly with latitude. Poleward of 30 degrees in both hemispheres, low-level clouds create a net cooling effect corresponding to radiative divergences of {minus}50 to {minus}100 W/m{sup 2}. It is likely that a combination of fogs, boundary-layer stratocumulus, and stratus clouds are the main contributors to this forcing. Models of the response of the microphysical and radiative properties of clouds to changes in aerosol abundance, for a variety of large-scale meteorological forcings, are important additions to GCMs used for the study of the role of Arctic systems in global climate. The overall objective of this research is the development of an aerosol/cloud microphysics parameterization of mixed-phase stratus and boundary-layer clouds which responds to variations in CCN and IN. The parameterization is to be designed for ultimate use in GCM simulations as a tool in understanding the role of CCN, IN, and Arctic clouds in radiation budgets. Several versions of the CSU RAMS (Regional Atmospheric Modeling System) will be used during the course of this work. The parameterizations developed in this research are intended for application in a single-column cloud model, designed as an adaptive grid model which can interface into a GCM vertical grid through distinct layers of the troposphere where the presence of layer clouds is expected.

  4. The Retrieval of Aerosol Optical Thickness Using the MERIS Instrument

    NASA Astrophysics Data System (ADS)

    Mei, L.; Rozanov, V. V.; Vountas, M.; Burrows, J. P.; Levy, R. C.; Lotz, W.

    2015-12-01

    Retrieval of aerosol properties for satellite instruments without shortwave-IR spectral information, multi-viewing, polarization and/or high-temporal observation ability is a challenging problem for spaceborne aerosol remote sensing. However, space based instruments like the MEdium Resolution Imaging Spectrometer (MERIS) and the successor, Ocean and Land Colour Instrument (OLCI) with high calibration accuracy and high spatial resolution provide unique abilities for obtaining valuable aerosol information for a better understanding of the impact of aerosols on climate, which is still one of the largest uncertainties of global climate change evaluation. In this study, a new Aerosol Optical Thickness (AOT) retrieval algorithm (XBAER: eXtensible Bremen AErosol Retrieval) is presented. XBAER utilizes the global surface spectral library database for the determination of surface properties while the MODIS collection 6 aerosol type treatment is adapted for the aerosol type selection. In order to take the surface Bidirectional Reflectance Distribution Function (BRDF) effect into account for the MERIS reduce resolution (1km) retrieval, a modified Ross-Li mode is used. The AOT is determined in the algorithm using lookup tables including polarization created using Radiative Transfer Model SCIATRAN3.4, by minimizing the difference between atmospheric corrected surface reflectance with given AOT and the surface reflectance calculated from the spectral library. The global comparison with operational MODIS C6 product, Multi-angle Imaging SpectroRadiometer (MISR) product, Advanced Along-Track Scanning Radiometer (AATSR) aerosol product and the validation using AErosol RObotic NETwork (AERONET) show promising results. The current XBAER algorithm is only valid for aerosol remote sensing over land and a similar method will be extended to ocean later.

  5. Radiative Impacts of Elevated Aerosol Layers from Different Origins

    NASA Astrophysics Data System (ADS)

    Sauer, D. N.; Weinzierl, B.; Gasteiger, J.; Heimerl, K.

    2014-12-01

    Aerosol particles are omnipresent in the Earth's atmosphere and have important impacts on weather and climate by their effects on the atmospheric radiative balance. With the advent of more and more sophisticated representations of atmospheric processes in earth system models, the lack of reliable input data on aerosols leads to significant uncertainties in the prediction of future climate scenarios. In recent years large discrepancies in radiative forcing estimates from aerosol layers in modeling studies have been revealed emphasizing the need for detailed and systematic observations of aerosols. Airborne in-situ measurements represent an important pillar for validating both model results and retrievals of aerosol distributions and properties from remote sensing methods on global scales. However, detailed observations are challenging and therefore are subject to substantial uncertainties themselves. Here we use data from airborne in-situ measurements of elevated aerosol layers from various field experiments in different regions of the world. The data set includes Saharan mineral dust layers over Africa, the Atlantic Ocean and the Caribbean from the SALTRACE and the SAMUM campaigns as well as long-range transported biomass burning aerosol layers from wild fires in the Sahel region and North America measured over the tropical Atlantic Ocean, Europe and the Arctic detected during SAMUM2, CONCERT2011, DC3 and ACCESS 2012. We aim to characterize the effects of the measured aerosol layers, in particular with respect to ageing, mixing state and vertical structure, on the overall atmospheric radiation budget as well as local heating and cooling rates. We use radiative transfer simulations of short and long-wave radiation and aerosol optical properties derived in a consistent way from the in-situ observations of microphysical properties using T-matrix calculations. The results of this characterization will help to improve the parameterization of the effects of elevated

  6. Aqueous aerosol SOA formation: impact on aerosol physical properties.

    PubMed

    Woo, Joseph L; Kim, Derek D; Schwier, Allison N; Li, Ruizhi; McNeill, V Faye

    2013-01-01

    Organic chemistry in aerosol water has recently been recognized as a potentially important source of secondary organic aerosol (SOA) material. This SOA material may be surface-active, therefore potentially affecting aerosol heterogeneous activity, ice nucleation, and CCN activity. Aqueous aerosol chemistry has also been shown to be a potential source of light-absorbing products ("brown carbon"). We present results on the formation of secondary organic aerosol material in aerosol water and the associated changes in aerosol physical properties from GAMMA (Gas-Aerosol Model for Mechanism Analysis), a photochemical box model with coupled gas and detailed aqueous aerosol chemistry. The detailed aerosol composition output from GAMMA was coupled with two recently developed modules for predicting a) aerosol surface tension and b) the UV-Vis absorption spectrum of the aerosol, based on our previous laboratory observations. The simulation results suggest that the formation of oligomers and organic acids in bulk aerosol water is unlikely to perturb aerosol surface tension significantly. Isoprene-derived organosulfates are formed in high concentrations in acidic aerosols under low-NO(x) conditions, but more experimental data are needed before the potential impact of these species on aerosol surface tension may be evaluated. Adsorption of surfactants from the gas phase may further suppress aerosol surface tension. Light absorption by aqueous aerosol SOA material is driven by dark glyoxal chemistry and is highest under high-NO(x) conditions, at high relative humidity, in the early morning hours. The wavelength dependence of the predicted absorption spectra is comparable to field observations and the predicted mass absorption efficiencies suggest that aqueous aerosol chemistry can be a significant source of aerosol brown carbon under urban conditions.

  7. Steps Toward an Aerosol-Type Global Climate Data Record

    NASA Astrophysics Data System (ADS)

    Kahn, R. A.

    2015-12-01

    Earth-observing satellites have produced a global record of aerosol optical depth approaching two decades in length. However a global record of aerosol properties at the level-of-detail required for constraining aerosol radiative forcing, aerosol-cloud interaction assessments, and many air quality applications is as yet lacking. Some aerosol-type information is derived from surface-based photometers, and qualitative classification is possible under favorable conditions from MISR, POLDER, and CALIPSO. More detailed particle microphysical properties are obtained from in situ measurements, but sampling is poor, and the suite of coincident measurements required for many applications is rarely acquired. Aerosol transport models can connect remote-sensing and in situ observations to specific aerosol sources, and extrapolate limited observational sampling in space and time. The biggest challenges to producing a global aerosol-type data record are filling gaps in detailed observations, maintaining global observing capabilities, and putting the pieces together. Obtaining detailed particle properties is probably the leading observational gap. One simplifying factor is that, for a given aerosol source and season, aerosol amounts can vary, but the particle properties tend to be repeatable. So an aircraft payload designed and deployed frequently enough to acquire the PDFs of the key variables could fill this gap; the SAM-CAAM (Systematic Aircraft Measurements to Characterize Aerosol Air Masses) concept aims at meeting this objective. Such data would add value to the entire satellite data record, improving the aerosol property assumptions in retrievals, and providing quantitative mass extinction efficiencies to translate between remote-sensing optical constraints and the aerosol mass book-kept in climate models. This will also help putting the pieces together in other ways, by improving the connection between remote-sensing particle types and those defined in models. The

  8. Remote Sensing of Spectral Aerosol Properties: A Classroom Experience

    NASA Technical Reports Server (NTRS)

    Levy, Robert C.; Pinker, Rachel T.

    2006-01-01

    Bridging the gap between current research and the classroom is a major challenge to today s instructor, especially in the sciences where progress happens quickly. NASA Goddard Space Flight Center and the University of Maryland teamed up in designing a graduate class project intended to provide a hands-on introduction to the physical basis for the retrieval of aerosol properties from state-of-the-art MODIS observations. Students learned to recognize spectral signatures of atmospheric aerosols and to perform spectral inversions. They became acquainted with the operational MODIS aerosol retrieval algorithm over oceans, and methods for its evaluation, including comparisons with groundbased AERONET sun-photometer data.

  9. A wind tunnel test of newly developed personal bioaerosol samplers.

    PubMed

    Su, Wei-Chung; Tolchinsky, Alexander D; Sigaev, Vladimir I; Cheng, Yung Sung

    2012-07-01

    In this study the performance of two newly developed personal bioaerosol samplers was evaluated. The two test samplers are cyclone-based personal samplers that incorporate a recirculating liquid film. The performance evaluations focused on the physical efficiencies that a personal bioaerosol sampler could provide, including aspiration, collection, and capture efficiencies. The evaluation tests were carried out in a wind tunnel, and the test personal samplers were mounted on the chest of a full-size manikin placed in the test chamber of the wind tunnel. Monodisperse fluorescent aerosols ranging from 0.5 to 20 microm were used to challenge the samplers. Two wind speeds of 0.5 and 2.0 m/sec were employed as the test wind speeds in this study. The test results indicated that the aspiration efficiency of the two test samplers closely agreed with the ACGIH inhalable convention within the size range of the test aerosols. The aspiration efficiency was found to be independent of the sampling orientation. The collection efficiency acquired from these two samplers showed that the 50% cutoff diameters were both around 0.6 microm. However the wall loss of these two test samplers increased as the aerosol size increased, and the wall loss of PAS-4 was considerably higher than that of PAS-5, especially in the aerosol size larger than 5 microm, which resulted in PAS-4 having a relatively lower capture efficiency than PAS-5. Overall, the PAS-5 is considered a better personal bioaerosol sampler than the PAS-4.

  10. Sugars in Antarctic aerosol

    NASA Astrophysics Data System (ADS)

    Barbaro, Elena; Kirchgeorg, Torben; Zangrando, Roberta; Vecchiato, Marco; Piazza, Rossano; Barbante, Carlo; Gambaro, Andrea

    2015-10-01

    The processes and transformations occurring in the Antarctic aerosol during atmospheric transport were described using selected sugars as source tracers. Monosaccharides (arabinose, fructose, galactose, glucose, mannose, ribose, xylose), disaccharides (sucrose, lactose, maltose, lactulose), alcohol-sugars (erythritol, mannitol, ribitol, sorbitol, xylitol, maltitol, galactitol) and anhydrosugars (levoglucosan, mannosan and galactosan) were measured in the Antarctic aerosol collected during four different sampling campaigns. For quantification, a sensitive high-pressure anion exchange chromatography was coupled with a single quadrupole mass spectrometer. The method was validated, showing good accuracy and low method quantification limits. This study describes the first determination of sugars in the Antarctic aerosol. The total mean concentration of sugars in the aerosol collected at the "Mario Zucchelli" coastal station was 140 pg m-3; as for the aerosol collected over the Antarctic plateau during two consecutive sampling campaigns, the concentration amounted to 440 and 438 pg m-3. The study of particle-size distribution allowed us to identify the natural emission from spores or from sea-spray as the main sources of sugars in the coastal area. The enrichment of sugars in the fine fraction of the aerosol collected on the Antarctic plateau is due to the degradation of particles during long-range atmospheric transport. The composition of sugars in the coarse fraction was also investigated in the aerosol collected during the oceanographic cruise.

  11. The economics and ethics of aerosol geoengineering strategies

    NASA Astrophysics Data System (ADS)

    Goes, Marlos; Keller, Klaus; Tuana, Nancy

    2010-05-01

    Anthropogenic greenhouse gas emissions are changing the Earth's climate and impose substantial risks for current and future generations. What are scientifically sound, economically viable, and ethically defendable strategies to manage these climate risks? Ratified international agreements call for a reduction of greenhouse gas emissions to avoid dangerous anthropogenic interference with the climate system. Recent proposals, however, call for a different approach: geoengineering climate by injecting aerosol precursors into the stratosphere. Published economic studies typically neglect the risks of aerosol geoengineering due to (i) a potential failure to sustain the aerosol forcing and (ii) due to potential negative impacts associated with aerosol forcings. Here we use a simple integrated assessment model of climate change to analyze potential economic impacts of aerosol geoengineering strategies over a wide range of uncertain parameters such as climate sensitivity, the economic damages due to climate change, and the economic damages due to aerosol geoengineering forcings. The simplicity of the model provides the advantages of parsimony and transparency, but it also imposes considerable caveats. For example, the analysis is based on a globally aggregated model and is hence silent on intragenerational distribution of costs and benefits. In addition, the analysis neglects the effects of future learning and is based on a simple representation of climate change impacts. We use this integrated assessment model to show three main points. First, substituting aerosol geoengineering for the reduction of greenhouse gas emissions can fail the test of economic efficiency. One key to this finding is that a failure to sustain the aerosol forcing can lead to sizeable and abrupt climatic changes. The monetary damages due to such a discontinuous aerosol geoengineering can dominate the cost-benefit analysis because the monetary damages of climate change are expected to increase with

  12. Infrared spectroscopy of aerosols

    NASA Astrophysics Data System (ADS)

    Mentel, Th.; Sebald, H.

    2003-04-01

    In our large Aerosol Chamber at the FZ Jülich we apply HR FTIR absorption spectroscopy for the determination of trace gases. In the FTIR spectra we also observe broad absorptions of several 10 to a few 100 cm-1 widths that arise from species in the condensed aerosol phase: liquid H_2O, NO_3^-, SO_42-, HSO_4^-, or dicarboxylic acids. Moreover, the aerosol droplets caused extinctions over several 1000 cm-1 by IR scattering. This allows for in-situ observation of changes in the condensed aerosol phase e.g. on HNO_3 uptake, like the shift of the sulfate/bisulfate equilibrium or the growth by water condensation. The IR absorptions of the condensed aerosol phase provide useful extra information in process studies, if they can be quantified. Therefore the absorption cross section, respective, the absorption index which is the imaginary part of the complex refractive index is needed. We set up an aerosol flow tube in which IR spectroscopy on a 8 m light path and aerosol size distribution measurements in the range from 20 nm - 10 μm can be performed simultaneously. We measured sulfate aerosols at several relative humidities (dry, metastable, deliquescent). We will demonstrate an iterative procedure based on Mie calculations and Kramers Kronig transformation to retrieve the absorption index from the observed IR spectra and the corresponding size distribution (for dry ammonium sulfate). We will compare resulting absorption indices for aqueous sodium bisulfate aerosols at several relative humidties with thermodynamic model calculations for the Na^+/H^+/HSO_4^-/SO_42-/H_2O system.

  13. Determining the Effects and Challenges of Incorporating Genetic Testing into Primary Care Management of Hypertensive Patients with African Ancestry

    PubMed Central

    Abul-Husn, NS; Ellis, S; Ramos, MA; Negron, R; Suprun, M; Zinberg, RE; Sabin, T; Hauser, D; Calman, N; Bagiella, E; Bottinger, EP

    2016-01-01

    People of African ancestry (Blacks) have increased risk of kidney failure due to numerous socioeconomic, environmental, and clinical factors. Two variants in the APOL1 gene are now thought to account for much of the racial disparity associated with hypertensive kidney failure in Blacks. However, this knowledge has not been translated into clinical care to help improve patient outcomes and address disparities. GUARDD is a randomized trial to evaluate the effects and challenges of incorporating genetic risk information into primary care. Hypertensive, non-diabetic, adults with self-reported African ancestry, without kidney dysfunction, are recruited from diverse clinical settings and randomized to undergo APOL1 genetic testing at baseline (intervention) or at one year (waitlist control). Providers are educated about genomics and APOL1. Guided by a genetic counselor, trained staff return APOL1 results to patients and provide low-literacy educational materials. Real-time clinical decision support tools alert clinicians of their patients’ APOL1 results and associated risk status at the point of care. Our academic-community-clinical partnership designed a study to generate information about the impact of genetic risk information on patient care (blood pressure and renal surveillance) and on patient and provider knowledge, attitudes, beliefs, and behaviors. GUARDD will help establish the effective implementation of APOL1 risk-informed management of hypertensive patients at high risk of CKD, and will provide a robust framework for future endeavors to implement genomic medicine in diverse clinical practices. It will also add to the important dialogue about factors that contribute to and may help eliminate racial disparities in kidney disease. PMID:26747051

  14. Diagnostic Differentiation of von Willebrand Disease Types 1 and 2 by von Willebrand Factor Multimer Analysis and DDAVP Challenge Test.

    PubMed

    Michiels, Jan Jacques; Smejkal, Petr; Penka, Miroslav; Batorova, Angelika; Pricangova, Tatiana; Budde, Ulrich; Vangenechten, Inge; Gadisseur, Alain

    2016-01-01

    The European Clinical Laboratory and Molecular (ECLM) classification of von Willebrand disease (vWD) is based on the splitting approach which uses sensitive and specific von Willebrand factor (vWF) assays with regard to the updated molecular data on structure and function of vWF gene and protein defects. A complete set of FVIII:C and vWF ristocetine cofactor, collagen binding, and antigen, vWF multimeric analysis in low- and medium-resolution gels, and responses to desmopressin (DDAVP) of FVIII:C and vWF parameters are mandatory. The ECLM classification distinguishes recessive types 1 and 3 vWD from recessive vWD 2C due to mutations in the D1 and D2 domains and vWD 2N due to mutations in the D'-FVIII-binding domain of vWF. The ECLM classification differentiates between mild vWD type 1 with variable penetrance of bleedings from symptomatic dominant type 1 vWD secretion defect and/or clearance defect with normal vWF multimers versus vWD 1M and 2M with normal or smeary vWF multimers in low- and medium-resolution gels. High-quality multimeric analysis of vWF in medium-resolution gels based on a DDAVP challenge test clearly delineates and distinguishes each of the dominant type 2 vWDs 1/2E, 2M, 2B, 2A, and 2D caused by vWF gene mutations in the D3 multimerization domain, loss or gain-of-function mutations in the glycoprotein Ib receptor A1 domain, gene mutations in the A2 proteolytic domain, and the C-terminal dimerization domain, respectively.

  15. Behavior of aerosols in a steam-air environment

    SciTech Connect

    Adams, R.E.; Tobias, M.L.; Longest, A.W.

    1985-01-01

    The behavior of aerosols assumed to be characteristic of those generated during light water reactor (LWR) accident sequences and released into containment is being studied in the Nuclear Safety Pilot Plant (NSPP) which is located at the Oak Ridge National Laboratory (ORNL). The program plan for the NSPP aerosol project provides for the study of the behavior, within containment, of simulated LWR accident aerosols emanating from fuel, reactor core structural materials, and from concrete-molten core materials interactions. The aerodynamic behavior of each of these aerosols was studied individually to establish its characteristics; current experiments involve mixtures of these aerosols to establish their interaction and collective behavior within containment. Tests have been conducted with U/sub 3/O/sub 8/ aerosols, Fe/sub 2/O/sub 3/ aerosols, and concrete aerosols in an environment of either dry air (relative humidity (RH) less than 20%) or steam-air (relative humidity (RH) approximately 100%) with aerosol mass concentration being the primary experimental variable.

  16. Testing the discrimination and detection limits of WorldView-2 imagery on a challenging invasive plant target

    NASA Astrophysics Data System (ADS)

    Robinson, T. P.; Wardell-Johnson, G. W.; Pracilio, G.; Brown, C.; Corner, R.; van Klinken, R. D.

    2016-02-01

    Invasive plants pose significant threats to biodiversity and ecosystem function globally, leading to costly monitoring and management effort. While remote sensing promises cost-effective, robust and repeatable monitoring tools to support intervention, it has been largely restricted to airborne platforms that have higher spatial and spectral resolutions, but which lack the coverage and versatility of satellite-based platforms. This study tests the ability of the WorldView-2 (WV2) eight-band satellite sensor for detecting the invasive shrub mesquite (Prosopis spp.) in the north-west Pilbara region of Australia. Detectability was challenged by the target taxa being largely defoliated by a leaf-tying biological control agent (Gelechiidae: Evippe sp. #1) and the presence of other shrubs and trees. Variable importance in the projection (VIP) scores identified bands offering greatest capacity for discrimination were those covering the near-infrared, red, and red-edge wavelengths. Wavelengths between 400 nm and 630 nm (coastal blue, blue, green, yellow) were not useful for species level discrimination in this case. Classification accuracy was tested on three band sets (simulated standard multispectral, all bands, and bands with VIP scores ≥1). Overall accuracies were comparable amongst all band-sets (Kappa = 0.71-0.77). However, mesquite omission rates were unacceptably high (21.3%) when using all eight bands relative to the simulated standard multispectral band-set (9.5%) and the band-set informed by VIP scores (11.9%). An incremental cover evaluation on the latter identified most omissions to be for objects <16 m2. Mesquite omissions reduced to 2.6% and overall accuracy significantly improved (Kappa = 0.88) when these objects were left out of the confusion matrix calculations. Very high mapping accuracy of objects >16 m2 allows application for mapping mesquite shrubs and coalesced stands, the former not previously possible, even with 3 m resolution hyperspectral

  17. Vertical profiles of cloud condensation nuclei, aerosol hygroscopicity, water uptake, and scattering across the United States

    NASA Astrophysics Data System (ADS)

    Lin, J. J.; Bougiatioti, A.; Nenes, A.; Anderson, B. E.; Beyersdorf, A. J.; Brock, C. A.; Gordon, T. D.; Lack, D.; Law, D. C.; Liao, J.; Middlebrook, A. M.; Richardson, M.; Thornhill, K. L., II; Winstead, E.; Wagner, N. L.; Welti, A.; Ziemba, L. D.

    2014-12-01

    The evolutions of vertical distributions of aerosol chemical, microphysical, hygroscopic, and optical properties present fundamental challenges to the understanding of ground-level air quality and radiative transfer, and few datasets exist to date for evaluation of atmospheric models. Data collected from recent NASA and NOAA field campaigns in the California Central Valley (DISCOVER-AQ), southeast United States (SENEX, SEAC4RS) and Texas (DISCOVER-AQ) allow for a unique opportunity to constrain vertical profiles of climate-relevant aerosol properties. This work presents in-situ aircraft measurements of cloud condensation nuclei (CCN) concentration and derivations of aerosol hygroscopicity, water uptake, and light scattering. Aerosol hygroscopicity is derived from CCN and aerosol measurements. Inorganic water uptake is calculated from aerosol composition using ISORROPIA, a chemical thermodynamic model, while organic water uptake is calculated from organic hygroscopicity. Aerosol scattering closure is performed between scattering from water uptake calculations and in-situ scattering measurements.

  18. Characterisation of non-toxigenic Clostridium spp. strains, to use as surrogates for non-proteolytic Clostridium botulinum in chilled food challenge testing.

    PubMed

    Parker, M D; Barrett, P I; Shepherd, J; Price, L J; Bull, S D

    2015-01-01

    Under many of the conditions studied, a two-strain cocktail of non-toxigenic Clostridium spp. was found to be suitable as a surrogate for non-proteolytic Clostridium botulinum, and has the potential for use in chilled food challenge tests measuring growth. Non-toxigenic surrogates could also be used in thermal process screening studies.

  19. Aerosol-cloud interaction using AATSR

    NASA Astrophysics Data System (ADS)

    Sogacheva, Larisa; Kolmonen, Pekka; Virtanen, Timo H.; Saponaro, Giulia; Kokhanovsky, Alexander; de Leeuw, Gerrit

    2014-05-01

    Aerosols and clouds play an important role in terrestrial atmospheric dynamics, thermodynamics, chemistry, and radiative transfer and are key elements of the water and energy cycles. The interactions between aerosol particles and cloud drops is critical to identifying how much they reflect solar radiation. Accurate evaluation of the effects of aerosols and clouds on climate requires global information on aerosol properties. Such global information can only be provided using satellite remote sensing. Among the satellite instruments used for aerosol and cloud retrieval is the Advanced Along-Track Scanning Radiometer (AATSR) on board the European Space Agency (ESA) satellite ENVISAT. Many instruments and retrieval techniques have been developed and applied to satellite data to derive cloud data products (Kokhanonsky et al., 2009). However, many problems still remain to be solved. They are mostly related to the usage of homogeneous, single-layered cloud model. Further issues exist for studies of thin clouds, where both cloud inhomogeniety, cloud fraction and the underlying surface bi-directional reflectance must be accounted for in the retrieval process. The aerosol retrieval algorithm (dual-view over land and single-view over ocean) was constructed for ATSR-2 data (e.g. Veefkind et al. 1998). The most recent version of ADV (AATSR Dual View) is described in Kolmenen et al. (2013). The ATSR dual-view allows retrieval without prior information about land surface reflectance. A semi-analytical cloud retrieval algorithm using backscattered radiation in 0.4-2.4 μm spectral region has been implemented to ADV for the determination of the optical thickness, the liquid water path, and the effective size of droplets from spectral measurements of the intensity of light reflected from water clouds with large optical thickness. In AacDV (AATSR aerosol and cloud Dual View) aerosol and cloud retrievals are combined. Cloud retrieval starts when cloud tests for aerosol retrieval show

  20. Parameter sensitivity study of Arctic aerosol vertical distribution in CAM5

    NASA Astrophysics Data System (ADS)

    Jiao, C.; Flanner, M.

    2015-12-01

    Arctic surface temperature response to light-absorbing aerosols (black carbon, brown carbon and dust) depends strongly on their vertical distributions. Improving model simulations of three dimensional aerosol fields in the remote Arctic region will therefore lead to improved projections of the climate change caused by aerosol emissions. In this study, we investigate how different physical parameterizations in the Community Atmosphere Model version 5 (CAM5) influence the simulated vertical distribution of Arctic aerosols. We design experiments to test the sensitivity of the simulated aerosol fields to perturbations of selected aerosol process-related parameters in the Modal Aerosol Module with seven lognormal modes (MAM7), such as those govern aerosol aging, in-cloud and below-cloud scavenging, aerosol hygroscopicity and so on. The simulations are compared with observed aerosol vertical distributions and total optical depth to assess model performance and quantify uncertainties associated with these model parameterizations. Observations applied here include Arctic aircraft measurements of black carbon and sulfate vertical profiles, along with Aerosol Robotic Network (AERONET) optical depth measurements. We also assess the utility of using High Spectral Resolution Lidar (HSRL) measurements from the ARM Barrow site to infer vertical profiles of aerosol extinction. The sensitivity study explored here will provide guidance for optimizing global aerosol simulations.

  1. A Search for Correlations Between Four Different Atmospheric Aerosol Measurement Systems Atop Rattlesnake Mountain, Washington

    NASA Astrophysics Data System (ADS)

    Milbrath, Brian

    2004-05-01

    Accurate atmospheric aerosol transport measurements are important to international nuclear test monitoring, emergency response, health and ecosystem toxicology, and climate change. An International Monitoring System (IMS) is being established which will include a suite of aerosol radionuclide sensors. To explore the possibility of using the IMS sites to improve the understanding of global atmospheric aerosol transport, four state-of-the-art aerosol measurement systems were placed atop Rattlesnake Mountain at Pacific Northwest National Laboratory. The Radionuclide Aerosol Sampler/Analyzer measures radionuclide concentration via gamma-ray spectroscopy. The Cascade Impactor Beam Analyzer Technique measures 30 elements in three aerosol sizes using PNNLâ's Ion Beams Materials Analysis Laboratory. The Tapered Element Oscillating Microbalance provides time-averaged aerosol mass concentrations for a range of sizes. The Multi-Filter Rotating Shadowband Radiometer measures the solar irradiance to derive an aerosol optical depth. Results and correlations from the four different detectors will be presented.

  2. Volcanic Aerosol Radiative Properties

    NASA Technical Reports Server (NTRS)

    Lacis, Andrew

    2015-01-01

    Large sporadic volcanic eruptions inject large amounts of sulfur bearing gases into the stratosphere which then get photochemically converted to sulfuric acid aerosol droplets that exert a radiative cooling effect on the global climate system lasting for several years.

  3. Palaeoclimate: Aerosols and rainfall

    NASA Astrophysics Data System (ADS)

    Partin, Jud

    2015-03-01

    Instrumental records have hinted that aerosol emissions may be shifting rainfall over Central America southwards. A 450-year-long precipitation reconstruction indicates that this shift began shortly after the Industrial Revolution.

  4. Development and evaluation of an ultrasonic personal aerosol sampler.

    PubMed

    Volckens, J; Quinn, C; Leith, D; Mehaffy, J; Henry, C S; Miller-Lionberg, D

    2017-03-01

    Assessing personal exposure to air pollution has long proven challenging due to technological limitations posed by the samplers themselves. Historically, wearable aerosol monitors have proven to be expensive, noisy, and burdensome. The objective of this work was to develop a new type of wearable monitor, an ultrasonic personal aerosol sampler (UPAS), to overcome many of the technological limitations in personal exposure assessment. The UPAS is a time-integrated monitor that features a novel micropump that is virtually silent during operation. A suite of onboard environmental sensors integrated with this pump measure and record mass airflow (0.5-3.0 L/min, accurate within 5%), temperature, pressure, relative humidity, light intensity, and acceleration. Rapid development of the UPAS was made possible through recent advances in low-cost electronics, open-source programming platforms, and additive manufacturing for rapid prototyping. Interchangeable cyclone inlets provided a close match to the EPA PM2.5 mass criterion (within 5%) for device flows at either 1.0 or 2.0 L/min. Battery life varied from 23 to 45 hours depending on sample flow rate and selected filter media. Laboratory tests of the UPAS prototype demonstrate excellent agreement with equivalent federal reference method samplers for gravimetric analysis of PM2.5 across a broad range of concentrations.

  5. Emergency Protection from Aerosols

    SciTech Connect

    Cristy, G.A.

    2001-11-13

    Expedient methods were developed that could be used by an average person, using only materials readily available, to protect himself and his family from injury by toxic (e.g., radioactive) aerosols. The most effective means of protection was the use of a household vacuum cleaner to maintain a small positive pressure on a closed house during passage of the aerosol cloud. Protection factors of 800 and above were achieved.

  6. Monodisperse aerosol generator

    DOEpatents

    Ortiz, Lawrence W.; Soderholm, Sidney C.

    1990-01-01

    An aerosol generator is described which is capable of producing a monodisperse aerosol within narrow limits utilizing an aqueous solution capable of providing a high population of seed nuclei and an organic solution having a low vapor pressure. The two solutions are cold nebulized, mixed, vaporized, and cooled. During cooling, particles of the organic vapor condense onto the excess seed nuclei, and grow to a uniform particle size.

  7. Recent Rainfall and Aerosol Chemistry From Bermuda

    NASA Astrophysics Data System (ADS)

    Landing, W. M.; Shelley, R.; Kadko, D. C.

    2014-12-01

    This project was devoted to testing the use of Be-7 as a tracer for quantifying trace element fluxes from the atmosphere to the oceans. Rainfall and aerosol samples were collected between June 15, 2011 and July 27, 2013 at the Bermuda Institute of Ocean Sciences (BIOS) located near the eastern end of the island of Bermuda. Collectors were situated near ground level, clear of surrounding vegetation, at a meteorological monitoring station in front of the BIOS laboratory, about 10 m above sea level. This is a Bermuda Air Quality Program site used for ambient air quality monitoring. To quantify the atmospheric deposition of Be-7, plastic buckets were deployed for collection of fallout over ~3 week periods. Wet deposition was collected for trace element analysis using a specially modified "GEOTRACES" N-CON automated wet deposition collector. Aerosol samples were collected with a Tisch TE-5170V-BL high volume aerosol sampler, modified to collect 12 replicate samples on acid-washed 47mm diameter Whatman-41 filters, using procedures identical to those used for the US GEOTRACES aerosol program (Morton et al., 2013). Aerosol and rainfall samples were analyzed for total Na, Mg, Al, P, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Rb, Sr, Zr, Cd, Sb, Ba, La, Ce, Nd, Pb, Th, and U using ICPMS. Confirming earlier data from Bermuda, strong seasonality in rainfall and aerosol loading and chemistry was observed, particularly for aerosol and rainfall Fe concentrations when Saharan dust arrives in July/August with SE trajectories.

  8. Aerosol Deposition and Solar Panel Performance

    NASA Astrophysics Data System (ADS)

    Arnott, W. P.; Rollings, A.; Taylor, S. J.; Parks, J.; Barnard, J.; Holmes, H.

    2015-12-01

    Passive and active solar collector farms are often located in relatively dry desert regions where cloudiness impacts are minimized. These farms may be susceptible to reduced performance due to routine or episodic aerosol deposition on collector surfaces. Intense episodes of wind blown dust deposition may negatively impact farm performance, and trigger need to clean collector surfaces. Aerosol deposition rate depends on size, morphology, and local meteorological conditions. We have developed a system for solar panel performance testing under real world conditions. Two identical 0.74 square meter solar panels are deployed, with one kept clean while the other receives various doses of aerosol deposition or other treatments. A variable load is used with automation to record solar panel maximum output power every 10 minutes. A collocated sonic anemometer measures wind at 10 Hz, allowing for both steady and turbulent characterization to establish a link between wind patterns and particle distribution on the cells. Multispectral photoacoustic instruments measure aerosol light scattering and absorption. An MFRSR quantifies incoming solar radiation. Solar panel albedo is measured along with the transmission spectra of particles collected on the panel surface. Key questions are: At what concentration does aerosol deposition become a problem for solar panel performance? What are the meteorological conditions that most strongly favor aerosol deposition, and are these predictable from current models? Is it feasible to use the outflow from an unmanned aerial vehicle hovering over solar panels to adequately clean their surface? Does aerosol deposition from episodes of nearby forest fires impact performance? The outlook of this research is to build a model that describes environmental effects on solar panel performance. Measurements from summer and fall 2015 will be presented along with insights gleaned from them.

  9. Development and Characterization of a Thermodenuder for Aerosol Volatility Measurements

    SciTech Connect

    Dr. Timothy Onasch

    2009-09-09

    This SBIR Phase I project addressed the critical need for improved characterization of carbonaceous aerosol species in the atmosphere. The proposed work focused on the development of a thermodenuder (TD) system capable of systematically measuring volatility profiles of primary and secondary organic aerosol species and providing insight into the effects of absorbing and nonabsorbing organic coatings on particle absorption properties. This work provided the fundamental framework for the generation of essential information needed for improved predictions of ambient aerosol loadings and radiative properties by atmospheric chemistry models. As part of this work, Aerodyne Research, Inc. (ARI) continued to develop and test, with the final objective of commercialization, an improved thermodenuder system that can be used in series with any aerosol instrument or suite of instruments (e.g., aerosol mass spectrometers-AMS, scanning mobility particle sizers-SMPS, photoacoustic absorption spectrometers-PAS, etc.) to obtain aerosol chemical, physical, and optical properties as a function of particle volatility. In particular, we provided the proof of concept for the direct coupling of our improved TD design with a full microphysical model to obtain volatility profiles for different organic aerosol components and to allow for meaningful comparisons between different TD-derived aerosol measurements. In a TD, particles are passed through a heated zone and a denuding (activated charcoal) zone to remove semi-volatile material. Changes in particle size, number concentration, optical absorption, and chemical composition are subsequently detected with aerosol instrumentation. The aerosol volatility profiles provided by the TD will strengthen organic aerosol emission inventories, provide further insight into secondary aerosol formation mechanisms, and provide an important measure of particle absorption (including brown carbon contributions and identification, and absorption enhancements

  10. RACORO aerosol data processing

    SciTech Connect

    Elisabeth Andrews

    2011-10-31

    The RACORO aerosol data (cloud condensation nuclei (CCN), condensation nuclei (CN) and aerosol size distributions) need further processing to be useful for model evaluation (e.g., GCM droplet nucleation parameterizations) and other investigations. These tasks include: (1) Identification and flagging of 'splash' contaminated Twin Otter aerosol data. (2) Calculation of actual supersaturation (SS) values in the two CCN columns flown on the Twin Otter. (3) Interpolation of CCN spectra from SGP and Twin Otter to 0.2% SS. (4) Process data for spatial variability studies. (5) Provide calculated light scattering from measured aerosol size distributions. Below we first briefly describe the measurements and then describe the results of several data processing tasks that which have been completed, paving the way for the scientific analyses for which the campaign was designed. The end result of this research will be several aerosol data sets which can be used to achieve some of the goals of the RACORO mission including the enhanced understanding of cloud-aerosol interactions and improved cloud simulations in climate models.

  11. A rotating bluff-body disc for reduced variability in wind tunnel aerosol studies.

    PubMed

    Koehler, Kirsten A; Anthony, T Renee; van Dyke, Michael; Volckens, John

    2011-01-01

    A rotating bluff-body disc (RBD) was developed to reduce spatiotemporal variability associated with sampling supermicron aerosol in low-velocity wind tunnels. The RBD is designed to rotate eight personal aerosol samplers around a circular path in a forward-facing plane aligned with the wind tunnel cross section. Rotation of the RBD allows each sampler to traverse an identical path about the wind tunnel cross section, which reduces the effects of spatial heterogeneity associated with dispersing supermicron aerosol in low-velocity wind tunnels. Samplers are positioned on the face of the RBD via sampling ports, which connect to an air manifold on the back of the disc. Flow through each sampler was controlled with a critical orifice or needle valve, allowing air to be drawn through the manifold with a single pump. A metal tube, attached to this manifold, serves as both the axis of rotation and the flow conduction path (between the samplers and the vacuum source). Validation of the RBD was performed with isokinetic samplers and 37-mm cassettes. For facing-the-wind tests, the rotation of the RBD significantly decreased intra-sampler variability when challenged with particle diameters from 1 to 100 μm. The RBD was then employed to determine the aspiration efficiency of Institute of Occupational Medicine (IOM) personal samplers under a facing-the-wind condition. Operation of IOM samplers on the RBD reduced the between-sampler variability for all particle sizes tested.

  12. PD-FiTE - an efficient method for calculating gas / liquid equilibria in atmospheric aerosol particles

    NASA Astrophysics Data System (ADS)

    Topping, D.; Lowe, D.; McFiggans, G.; Barley, M.

    2009-04-01

    Assessing the impact of atmospheric aerosol particles on the environment requires adequate representation of appropriate key processes within large scale models. In the absence of primary particulate material, interactions between the atmospheric gaseous components and particles means that the chemical nature of the particles is largely determined by the availability of condensable gaseous material, such as sulphuric and nitric acids, and by the ambient environmental conditions. Gas to particle mass transfer of semi-volatile components,driven by a difference in equilibrium and actual partial pressures above an aerosol particle, is an important factor in determining the evolving chemical composition of the particle and is necessary for predicting aerosol loading and composition. The design of an appropriate framework required for parameterizations of key variables is challenging. These thermodynamic frameworks are often numerically very complex, resulting in significant computational expense. Three dimensional chemical and aerosol transport models demand that computational expense be kept at a minimum,resulting in a trade-off between accuracy and efficiency. To calculate the equilibrium vapour pressure above a solution requires treatment of solution nonideality. This is manifest through activity coefficients of components pertinent to each condensing specie. However, activity coefficients are complex functions of the solution composition. Parameterisation of activity coefficients provides the main focus of this work largely because reducing the numerical complexity whilst retaining a good level of accuracy is very challenging. The approach presented here, the hybrid Partial Derivative Fitted Taylor Expansion (PDFiTE) (Topping et al 2008), builds on previously reported work, with an aim to derive parameters for an accurate and computationally efficient framework through coupling with a complex thermodynamic model. Such a reduction in complexity is important as it is

  13. Quantifying phenotypic flexibility as the response to a high-fat challenge test in different states of metabolic health.

    PubMed

    Kardinaal, Alwine F M; van Erk, Marjan J; Dutman, Alice E; Stroeve, Johanna H M; van de Steeg, Evita; Bijlsma, Sabina; Kooistra, Teake; van Ommen, Ben; Wopereis, Suzan

    2015-11-01

    Metabolism maintains homeostasis at chronic hypercaloric conditions, activating postprandial response mechanisms, which come at the cost of adaptation processes such as energy storage, eventually with negative health consequences. This study quantified the metabolic adaptation capacity by studying challenge response curves. After a high-fat challenge, the 8 h response curves of 61 biomarkers related to adipose tissue mass and function, systemic stress, metabolic flexibility, vascular health, and glucose metabolism was compared between 3 metabolic health stages: 10 healthy men, before and after 4 wk of high-fat, high-calorie diet (1300 kcal/d extra), and 9 men with metabolic syndrome (MetS). The MetS subjects had increased fasting concentrations of biomarkers representing the 3 core processes, glucose, TG, and inflammation control, and the challenge response curves of most biomarkers were altered. After the 4 wk hypercaloric dietary intervention, these 3 processes were not changed, as compared with the preintervention state in the healthy subjects, whereas the challenge response curves of almost all endocrine, metabolic, and inflammatory processes regulating these core processes were altered, demonstrating major molecular physiologic efforts to maintain homeostasis. This study thus demonstrates that change in challenge response is a more sensitive biomarker of metabolic resilience than are changes in fasting concentrations.

  14. Instrumentation for Aerosol and Gas Speciation

    NASA Technical Reports Server (NTRS)

    Coggiola, Michael J.

    1998-01-01

    Using support from NASA Grant No. NAG 2-963, SRI International successfully completed the project, entitled, 'Instrumentation for Aerosol and Gas Speciation.' This effort (SRI Project 7383) covered the design, fabrication, testing, and deployment of a real-time aerosol speciation instrument in NASA's DC-8 aircraft during the Spring 1996 SUbsonic aircraft: Contrail and Cloud Effects Special Study (SUCCESS) mission. This final technical report describes the pertinent details of the instrument design, its abilities, its deployment during SUCCESS and the data acquired from the mission, and the post-mission calibration, data reduction, and analysis.

  15. Super-droplet method as a versatile numerical approach for representing aerosol-cloud-aerosol interactions.

    NASA Astrophysics Data System (ADS)

    Jaruga, Anna; Arabas, Sylwester; Pawlowska, Hanna

    2013-04-01

    Aerosol interacts with clouds by serving as cloud condensation nuclei (CCN). Its physical and chemical properties are one of the factors defining cloud droplet size distribution. On the other hand, clouds process atmospheric aerosol taking part in its wet deposition and CCN regeneration through evaporation of cloud droplets and drizzle. Physical and chemical properties of the regenerated CCN may be altered if the evaporated droplets go through collisional growth or irreversible chemical reactions. The main challenge of representing these aerosol-cloud interactions in a numerical cloud model stems from the need to track the properties of the drop nuclei throughout the cloud lifecycle. A class of methods allowing such studies is the Lagrangian particle-based simulation technique. In a simulation of cloud, each modeled particle represents a multiplicity of particles of the same nucleus type, position and size. During the simulation particle sizes change in a continuous way from CCN-sized to rain drop particles. Tracking microphysical properties of modeled particles is an inherent feature of the particle-based frameworks, making them suitable for studying aerosol-cloud-aerosol interactions. Super-droplet method is a Lagrangian technique introduced by Shima et al. (2009) featuring an efficient Monte-Carlo type solver for particle coalescence. In this study a new implementation of the super-droplet method, using the kappa-Koehler parametrisation of aerosol composition and an aqueous chemistry module for representing irreversible oxidation, will be presented. Components of the developed model will be discussed using a single-eddy prescribed-flow framework, focusing solely on the microphysical aspects of simulations. Example case will mimic a Stratocumulus cloud and depict cloud-aerosol interactions resolved by the model.

  16. Organic Aerosols from SÃO Paulo and its Relationship with Aerosol Absorption and Scattering Properties

    NASA Astrophysics Data System (ADS)

    Artaxo, P.; Brito, J. F.; Rizzo, L. V.

    2012-12-01

    The megacity of São Paulo with its 19 million people and 7 million cars is a challenge from the point of view of air pollution. High levels of organic aerosols, PM10, black carbon and ozone and the peculiar situation of the large scale use of ethanol fuel makes it a special case. Little is known about the impact of ethanol on air quality and human health and the increase of ethanol as vehicle fuel is rising worldwide An experiment was designed to physico-chemical properties of aerosols in São Paulo, as well as their optical properties. Aerosol size distribution in the size range of 1nm to 10 micrometers is being measured with a Helsinki University SMPS (Scanning Mobility Particle Sizer), an NAIS (Neutral ion Spectrometer) and a GRIMM OPC (Optical Particle Counter). Optical properties are being measured with a TSI Nephelometer and a Thermo MAAP (Multi Angle Absorption Photometer). A CIMEL sunphotometer from the AERONET network measure the aerosol optical depth. Furthermore, a Proton-Transfer-Reaction Mass Spectrometer (PTR-MS) and an Aerosol Chemical Speciation Monitor (ACSM) are used to real-time VOC analysis and aerosol composition, respectively. The ACSM was operated for 3 months continuosly during teh wintertime of 2012. The measured total particle concentration typically varies between 10,000 and 30,000 cm-3 being the lowest late in the night and highest around noon and frequently exceeding 50,000 cm-3. Clear diurnal patterns in aerosol optical properties were observed. Scattering and absorption coefficients typically range between 20 and 100 Mm-1 at 450 nm, and between 10 to 40 Mm-1 at 637 nm, respectively, both of them peaking at 7:00 local time, the morning rush hour. The corresponding single scattering albedo varies between 0.50 and 0.85, indicating a significant contribution of primary absorbing particles to the aerosol population. During the first month a total of seven new particle formation events were observed with growth rates ranging from 9 to 25

  17. Intercomparison of aerosol instruments: number concentration

    SciTech Connect

    Knutson, E O; Sinclair, D; Tu, K W; Hinchliffe, L; Franklin, H

    1982-05-01

    An intercomparison of aerosol instruments conducted February 23-27, 1981, at the Environmental Measurements Laboratory (EML) focused on five instruments: the Pollak and TSI condensation nucleus counters; the Active Scattering Aerosol Spectrometer (ASAS-X); and two aerosol electrometers. Test aerosols of sodium chloride and ammonium fluorescein generated by nebulization/electrostatic classification were used to obtain 195 lines of comparison data. Concentrations measured by the ASAS-X and the TSI aerosol electrometer averaged respectively 1.388 and 1.581 times that measured by the Pollak. These ratios were very stable during the week and there was little effect of particle size or material. Most other comparisons were equally stable. However, a review of past work at EML and elsewhere led to the disturbing conclusion that these ratios may change from year to year, or from season to season. A filter sample was taken from microscopy, concurrent with readings from the ASAS-X and the TSI condensation nucleus counters. In this sample, the two instruments differed by 20%. Within its 20% uncertainty, the filter result matched both the TSI and ASAS-X readings.

  18. Evolution of ozone, particulates, and aerosol direct radiative forcing in the vicinity of Houston using a fully coupled meteorology-chemistry-aerosol model

    NASA Astrophysics Data System (ADS)

    Fast, Jerome D.; Gustafson, William I.; Easter, Richard C.; Zaveri, Rahul A.; Barnard, James C.; Chapman, Elaine G.; Grell, Georg A.; Peckham, Steven E.

    2006-11-01

    A new fully coupled meteorology-chemistry-aerosol model is used to simulate the urban- to regional-scale variations in trace gases, particulates, and aerosol direct radiative forcing in the vicinity of Houston over a 5 day summer period. Model performance is evaluated using a wide range of meteorological, chemistry, and particulate measurements obtained during the 2000 Texas Air Quality Study. The predicted trace gas and particulate distributions were qualitatively similar to the surface and aircraft measurements with considerable spatial variations resulting from urban, power plant, and industrial sources of primary pollutants. Sulfate, organic carbon, and other inorganics were the largest constituents of the predicted particulates. The predicted shortwave radiation was 30 to 40 W m-2 closer to the observations when the aerosol optical properties were incorporated into the shortwave radiation scheme; however, the predicted hourly aerosol radiative forcing was still underestimated by 10 to 50 W m-2. The predicted aerosol radiative forcing was larger over Houston and the industrial ship channel than over the rural areas, consistent with surface measurements. The differences between the observed and simulated aerosol radiative forcing resulted from transport errors, relative humidity errors in the upper convective boundary layer that affect aerosol water content, secondary organic aerosols that were not yet included in the model, and uncertainties in the primary particulate emission rates. The current model was run in a predictive mode and demonstrates the challenges of accurately simulating all of the meteorological, chemical, and aerosol parameters over urban to regional scales that can affect aerosol radiative forcing.

  19. Steady generation of aerosols with an improved constant output atomizer

    NASA Technical Reports Server (NTRS)

    Dea, J. Y.; Katz, U.

    1981-01-01

    It is common practice to generate laboratory aerosols of soluble materials with pneumatic atomizers. In a typical device, a solution of the substance to be aerosolized is injected into a jet of air and the liquid is broken up into very small droplets. After forced evaporation, a dry aerosol of the solute is produced. A number of commercially available devices were tested, and despite differences in design, all the atomizers tested suffered from short- and/or long-term fluctuations of their output particle number concentrations. The mechanisms responsible for atomizer instabilities are discussed and methods for alleviating these problems are considered.

  20. Aerosol absorption measurement with a sinusoidal phase modulating fiber optic photo thermal interferometer

    NASA Astrophysics Data System (ADS)

    Li, Shuwang; Shao, Shiyong; Mei, Haiping; Rao, Ruizhong

    2016-10-01

    Aerosol light absorption plays an important role in the earth's atmosphere direct and semi-direct radiate forcing, simultaneously, it also has a huge influence on the visibility impairment and laser engineering application. Although various methods have been developed for measuring aerosol light absorption, huge challenge still remains in precision, accuracy and temporal resolution. The main reason is that, as a part of aerosol light extinction, aerosol light absorption always generates synchronously with aerosol light scattering, and unfortunately aerosol light scattering is much stronger in most cases. Here, a novel photo-thermal interferometry is proposed only for aerosol absorption measurement without disturbance from aerosol scattering. The photo-thermal interferometry consists of a sinusoidal phase-modulating single mode fiber-optic interferometer. The thermal dissipation, caused by aerosol energy from photo-thermal conversion when irritated by pump laser through interferometer, is detected. This approach is completely insensitive to aerosol scattering, and the single mode fiber-optic interferometer is compact, low-cost and insensitive to the polarization shading. The theory of this technique is illustrated, followed by the basic structure of the sinusoidal phase-modulating fiber-optic interferometer and demodulation algorithms. Qualitative and quantitative analysis results show that the new photo-thermal interference is a potential approach for aerosol absorption detection and environmental pollution detection.

  1. Preliminary results of the aerosol optical depth retrieval in Johor, Malaysia

    NASA Astrophysics Data System (ADS)

    Lim, H. Q.; Kanniah, K. D.; Lau, A. M. S.

    2014-02-01

    Monitoring of atmospheric aerosols over the urban area is important as tremendous amounts of pollutants are released by industrial activities and heavy traffic flow. Air quality monitoring by satellite observation provides better spatial coverage, however, detailed aerosol properties retrieval remains a challenge. This is due to the limitation of aerosol retrieval algorithm on high reflectance (bright surface) areas. The aim of this study is to retrieve aerosol optical depth over urban areas of Iskandar Malaysia; the main southern development zone in Johor state, using Moderate Resolution Imaging Spectroradiometer (MODIS) 500 m resolution data. One of the important steps is the aerosol optical depth retrieval is to characterise different types of aerosols in the study area. This information will be used to construct a Look Up Table containing the simulated aerosol reflectance and corresponding aerosol optical depth. Thus, in this study we have characterised different aerosol types in the study area using Aerosol Robotic Network (AERONET) data. These data were processed using cluster analysis and the preliminary results show that the area is consisting of coastal urban (65%), polluted urban (27.5%), dust particles (6%) and heavy pollution (1.5%) aerosols.

  2. Contact ice nucleation by submicron atmospheric aerosols

    NASA Technical Reports Server (NTRS)

    Deshler, T.

    1982-01-01

    An apparatus designed to measure the concentrations of submicron contact ice nuclei is described. Here, natural forces transfer nuclei to supercooled sample drops suspended in an aerosol stream. Experimental measurements of the scavenging rate of the sample drops for several humidities and aerosol sizes are found to be in agreement with theory to within a factor of two. This fact, together with the statistical tests showing a difference between the data and control samples, is seen as indicating that a reliable measurement of the concentrations of submicron contact ice nuclei has been effected. A figure is included showing the ice nucleus concentrations as a function of temperature and assumed aerosol radius. For a 0.01 micron radius, the average is 1/liter at -15 C and 3/liter at -18 C. It is noted that the measurements are in fair agreement with ice crystal concentrations in stable winter clouds measured over Elk Mountain, WY (Vali et al., 1982).

  3. The Aerosol Modeling Testbed: A community tool to objectively evaluate aerosol process modules

    SciTech Connect

    Fast, Jerome D.; Gustafson, William I.; Chapman, Elaine G.; Easter, Richard C.; Rishel, Jeremy P.; Zaveri, Rahul A.; Grell, Georg; Barth, Mary

    2011-03-02

    This study describes a new modeling paradigm that significantly advances how the third activity is conducted while also fully exploiting data and findings from the first two activities. The Aerosol Modeling Testbed (AMT) is a computational framework for the atmospheric sciences community that streamlines the process of testing and evaluating aerosol process modules over a wide range of spatial and temporal scales. The AMT consists of a fully-coupled meteorology-chemistry-aerosol model, and a suite of tools to evaluate the performance of aerosol process modules via comparison with a wide range of field measurements. The philosophy of the AMT is to systematically and objectively evaluate aerosol process modules over local to regional spatial scales that are compatible with most field campaigns measurement strategies. The performance of new treatments can then be quantified and compared to existing treatments before they are incorporated into regional and global climate models. Since the AMT is a community tool, it also provides a means of enhancing collaboration and coordination among aerosol modelers.

  4. Particle-Resolved Modeling of Aerosol Mixing State in an Evolving Ship Plume

    NASA Astrophysics Data System (ADS)

    Riemer, N. S.; Tian, J.; Pfaffenberger, L.; Schlager, H.; Petzold, A.

    2011-12-01

    The aerosol mixing state is important since it impacts the particles' optical and CCN properties and thereby their climate impact. It evolves continuously during the particles' residence time in the atmosphere as a result of coagulation with other particles and condensation of secondary aerosol species. This evolution is challenging to represent in traditional aerosol models since they require the representation of a multi-dimensional particle distribution. While modal or sectional aerosol representations cannot practically resolve the aerosol mixing state for more than a few species, particle-resolved models store the composition of many individual aerosol particles directly. They thus sample the high-dimensional composition state space very efficiently and so can deal with tens of species, fully resolving the mixing state. Here we use the capabilities of the particle-resolved model PartMC-MOSAIC to simulate the evolution of particulate matter emitted from marine diesel engines and compare the results to aircraft measurements made in the English Channel in 2007 as part of the European campaign QUANTIFY. The model was initialized with values of gas concentrations and particle size distributions and compositions representing fresh ship emissions. These values were obtained from a test rig study in the European project HERCULES in 2006 using a serial four-stroke marine diesel engine operating on high-sulfur heavy fuel oil. The freshly emitted particles consisted of sulfate, black carbon, organic carbon and ash. We then tracked the particle population for several hours as it evolved undergoing coagulation, dilution with the background air, and chemical transformations in the aerosol and gas phase. This simulation was used to compute the evolution of CCN properties and optical properties of the plume on a per-particle basis. We compared our results to size-resolved data of aged ship plumes from the QUANTIFY Study in 2007 and showed that the model was able to reproduce

  5. The Influence of Volcanic Aerosols on Planetary Habitability

    NASA Astrophysics Data System (ADS)

    Chen, Howard; Horton, Daniel Ethan

    2017-01-01

    On rocky planetary bodies such as Proxima Centuri b, the detection of sulphate aerosols may indicate volcanism and tectonic activity; ingredients hypothesized to be necessary for planetary habitability. However, due to the effect of atmospheric aerosols on a planet’s energy balance, coupled with eruption constituent and frequency uncertainties, the potential impact of volcanic activity on planetary habitability remains unresolved. Here, we employ multi-column climate models in conjunction with a parameter space approach to test the effect of volcanic aerosols on planetary climate with various climate sensitivities. Preliminary results indicate that volcanic activity could provide a means of extending the inner edge of the habitable zone (IHZ), depending on eruption constituents and frequency. Previous work using transit spectra simulations have demonstrated the possibility of detecting transient aerosols of volcanic origin. Our work investigates the range of habitability implications detection of such aerosols would imply.

  6. Secondary Ion Mass Spectrometry of Environmental Aerosols

    SciTech Connect

    Gaspar, Daniel J.; Cliff, John B.

    2010-08-01

    Atmospheric particles influence many aspects of climate, air quality and human health. Understanding the composition, chemistry and behavior of atmospheric aerosols is a key remaining challenge in improving climate models. Furthermore, particles may be traced back to a particular source based on composition, stable isotope ratios, or the presence of particular surface chemistries. Finally, the characterization of atmospheric particles in the workplace plays an important role in understanding the potential for exposure and environmental and human health effects to engineered and natural nanoscale particles. Secondary ion mass spectrometry (SIMS) is a useful tool in determining any of several aspects of the structure, composition and chemistry of these particles. Often used in conjunction with other surface analysis and electron microscopy methods, SIMS has been used to determine or confirm reactions on and in particles, the presence of particular organic species on the surface of atmospheric aerosols and several other interesting and relevant findings. Various versions of SIMS instruments – dynamic SIMS, time of flight secondary ion mass spectrometry or TOF-SIMS, nanoSIMS – have been used to determine specific aspects of aerosol structure and chemistry. This article describes the strengths of each type of SIMS instrument in the characterization of aerosols, along with guidance on sample preparation, specific characterization specific to the particular information sought in the analysis. Examples and guidance are given for each type of SIMS analysis.

  7. Artificial ultra-fine aerosol tracers for highway transect studies

    NASA Astrophysics Data System (ADS)

    Cahill, Thomas A.; Barnes, David E.; Wuest, Leann; Gribble, David; Buscho, David; Miller, Roger S.; De la Croix, Camille

    2016-07-01

    The persistent evidence of health impacts of roadway aerosols requires extensive information for urban planning to avoid putting populations at risk, especially in-fill projects. The required information must cover both highway aerosol sources as well as transport into residential areas under a variety of roadway configurations, traffic conditions, downwind vegetation, and meteorology. Such studies are difficult and expensive to do, but were easier in the past when there was a robust fine aerosol tracer uniquely tied to traffic - lead. In this report we propose and test a modern alternative, highway safety flare aerosols. Roadway safety flares on vehicles in traffic can provide very fine and ultra-fine aerosols of unique composition that can be detected quantitatively far downwind of roadways due to a lack of upwind interferences. The collection method uses inexpensive portable aerosol collection hardware and x-ray analysis protocols. The time required for each transect is typically 1 h. Side by side tests showed precision at ± 4%. We have evaluated this technique both by aerosol removal in vegetation in a wind tunnel and by tracking aerosols downwind of freeways as a function of season, highway configuration and vegetation coverage. The results show that sound walls for at-grade freeways cause freeway pollution to extend much farther downwind than standard models predict. The elevated or fill section freeway on a berm projected essentially undiluted roadway aerosols at distances well beyond 325 m, deep into residential neighborhoods. Canopy vegetation with roughly 70% cover reduced very fine and ultra-fine aerosols by up to a factor of 2 at distances up to 200 m downwind.

  8. Stratospheric Aerosol and Gas Experiment (SAGE) II and III Aerosol Extinction Measurements in the Arctic Middle and Upper Troposphere

    NASA Technical Reports Server (NTRS)

    Treffeisen, R. E.; Thomason, L. W.; Strom, J.; Herber, A. B.; Burton, S. P.; Yamanouchi, T.

    2006-01-01

    In recent years, substantial effort has been expended toward understanding the impact of tropospheric aerosols on Arctic climate and chemistry. A significant part of this effort has been the collection and documentation of extensive aerosol physical and optical property data sets. However, the data sets present significant interpretive challenges because of the diverse nature of these measurements. Among the longest continuous records is that by the spaceborne Stratospheric Aerosol and Gas Experiment (SAGE) II. Although SAGE tropospheric measurements are restricted to the middle and upper troposphere, they may be able to provide significant insight into the nature and variability of tropospheric aerosol, particularly when combined with ground and airborne observations. This paper demonstrates the capacity of aerosol products from SAGE II and its follow-on experiment SAGE III to describe the temporal and vertical variations of Arctic aerosol characteristics. We find that the measurements from both instruments are consistent enough to be combined. Using this combined data set, we detect a clear annual cycle in the aerosol extinction for the middle and upper Arctic troposphere.

  9. Atmospheric Chemistry: Nature's plasticized aerosols

    NASA Astrophysics Data System (ADS)

    Ziemann, Paul J.

    2016-01-01

    The structure of atmospheric aerosol particles affects their reactivity and growth rates. Measurements of aerosol properties over the Amazon rainforest indicate that organic particles above tropical rainforests are simple liquid drops.

  10. Palaeoclimate: Aerosols shift lake ecosystem

    NASA Astrophysics Data System (ADS)

    Dowsett, Harry J.

    2017-02-01

    Anthropogenic aerosols over the Chinese Loess Plateau have diminished monsoon precipitation and concomitant soil erosion that plagues the region. Now, a reconstruction documents the differences between historical warming events and the present, highlighting the paradoxical implications of decreasing atmospheric aerosols.

  11. Generation of aerosolized drugs.

    PubMed

    Wolff, R K; Niven, R W

    1994-01-01

    The expanding use of inhalation therapy has placed demands on current aerosol generation systems that are difficult to meet with current inhalers. The desire to deliver novel drug entities such as proteins and peptides, as well as complex formulations including liposomes and microspheres, requires delivery systems of improved efficiency that will target the lung in a reproducible manner. These efforts have also been spurred by the phase out of chlorofluorocarbons (CFCs) and this has included a directed search for alternative propellants. Consequently, a variety of new aerosol devices and methods of generating aerosols are being studied. This includes the use of freon replacement propellants, dry powder generation systems, aqueous unit spray systems and microprocessor controlled technologies. Each approach has advantages and disadvantages depending upon each principle of action and s