29 CFR 1910.134 - Respiratory protection.

Code of Federal Regulations, 2013 CFR

2013-07-01

... impact and penetration. High efficiency particulate air (HEPA) filter means a filter that is at least 99... as a high efficiency particulate air (HEPA) filter, or an air-purifying respirator equipped with a... frequency of respirator use (including use for rescue and escape); (C) The expected physical work effort; (D...

Institute for Clean Energy Technology Mississippi State University NSR&D Aged HEPA Filter Study Final Report

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

Jacks, Robert; Stormo, Julie; Rose, Coralie

Data have demonstrated that filter media lose tensile strength and the ability to resist the effects of moisture as a function of age. Testing of new and aged filters needs to be conducted to correlate reduction of physical strength of HEPA media to the ability of filters to withstand upset conditions. Appendix C of the Nuclear Air Cleaning Handbook provides the basis for DOE’s HEPA filter service life guidance. However, this appendix also points out the variability of data, and it does not correlate performance of aged filters to degradation of media due to age. Funding awarded by NSR&D tomore » initiate full-scale testing of aged HEPA filters addresses the issue of correlating media degradation due to age with testing of new and aged HEPA filters under a generic design basis event set of conditions. This funding has accelerated the process of describing this study via: (1) establishment of a Technical Working Group of all stakeholders, (2) development and approval of a test plan, (3) development of testing and autopsy procedures, (4) acquiring an initial set of aged filters, (5) testing the initial set of aged filters, and (6) developing the filter test report content for each filter tested. This funding was very timely and has moved the project forward by at least three years. Activities have been correlated with testing conducted under DOE-EM funding for evaluating performance envelopes for AG-1 Section FC Separator and Separatorless filters. This coordination allows correlation of results from the NSR&D Aged Filter Study with results from testing new filters of the Separator and Separatorless Filter Study. DOE-EM efforts have identified approximately 100 more filters of various ages that have been stored under Level B conditions. NSR&D funded work allows a time for rigorous review among subject matter experts before moving forward with development of the testing matrix that will be used for additional filters. The NSR&D data sets are extremely valuable in as much as establishing a selfimproving, NQA-1 program capable of advancing the service lifetime study of HEPA filters. The data and reports are available for careful and critical review by subject matter experts before the next set of filters is tested and can be found in the appendices of this final report. NSR&D funds have not only initiated the Aged HEPA Filter Study alluded to in Appendix C of the NACH, but have also enhanced the technical integrity and effectiveness of all of the follow-on testing for this long-term study.« less

Comparison of MERV 16 and HEPA filters for cab filtration of underground mining equipment.

PubMed

Cecala, A B; Organiscak, J A; Noll, J D; Zimmer, J A

2016-08-01

Significant strides have been made in optimizing the design of filtration and pressurization systems used on the enclosed cabs of mobile mining equipment to reduce respirable dust and provide the best air quality to the equipment operators. Considering all of the advances made in this area, one aspect that still needed to be evaluated was a comparison of the efficiencies of the different filters used in these systems. As high-efficiency particulate arrestance (HEPA) filters provide the highest filtering efficiency, the general assumption would be that they would also provide the greatest level of protection to workers. Researchers for the U.S. National Institute for Occupational Safety and Health (NIOSH) speculated, based upon a previous laboratory study, that filters with minimum efficiency reporting value, or MERV rating, of 16 may be a more appropriate choice than HEPA filters in most cases for the mining industry. A study was therefore performed comparing HEPA and MERV 16 filters on two kinds of underground limestone mining equipment, a roof bolter and a face drill, to evaluate this theory. Testing showed that, at the 95-percent confidence level, there was no statistical difference between the efficiencies of the two types of filters on the two kinds of mining equipment. As the MERV 16 filters were less restrictive, provided greater airflow and cab pressurization, cost less and required less-frequent replacement than the HEPA filters, the MERV 16 filters were concluded to be the optimal choice for both the roof bolter and the face drill in this comparative-analysis case study. Another key finding of this study is the substantial improvement in the effectiveness of filtration and pressurization systems when using a final filter design.

Comparison of MERV 16 and HEPA filters for cab filtration of underground mining equipment

PubMed Central

Cecala, A.B.; Organiscak, J.A.; Noll, J.D.; Zimmer, J.A.

2016-01-01

Significant strides have been made in optimizing the design of filtration and pressurization systems used on the enclosed cabs of mobile mining equipment to reduce respirable dust and provide the best air quality to the equipment operators. Considering all of the advances made in this area, one aspect that still needed to be evaluated was a comparison of the efficiencies of the different filters used in these systems. As high-efficiency particulate arrestance (HEPA) filters provide the highest filtering efficiency, the general assumption would be that they would also provide the greatest level of protection to workers. Researchers for the U.S. National Institute for Occupational Safety and Health (NIOSH) speculated, based upon a previous laboratory study, that filters with minimum efficiency reporting value, or MERV rating, of 16 may be a more appropriate choice than HEPA filters in most cases for the mining industry. A study was therefore performed comparing HEPA and MERV 16 filters on two kinds of underground limestone mining equipment, a roof bolter and a face drill, to evaluate this theory. Testing showed that, at the 95-percent confidence level, there was no statistical difference between the efficiencies of the two types of filters on the two kinds of mining equipment. As the MERV 16 filters were less restrictive, provided greater airflow and cab pressurization, cost less and required less-frequent replacement than the HEPA filters, the MERV 16 filters were concluded to be the optimal choice for both the roof bolter and the face drill in this comparative-analysis case study. Another key finding of this study is the substantial improvement in the effectiveness of filtration and pressurization systems when using a final filter design. PMID:27524838

40 CFR 721.10411 - Alkanenitrile, bis(cyanoalkyl)amino (generic) (P-07-537).

Code of Federal Regulations, 2012 CFR

2012-07-01

... with N100 (if oil aerosols absent), R100, or P100 filters; NIOSH-certified powered air-purifying respirator equipped with a loose- fitting hood or helmet and high efficiency particulate air (HEPA) filters... HEPA filters; or NIOSH-certified supplied-air respirator operated in pressure demand or continuous flow...

40 CFR 721.10411 - Alkanenitrile, bis(cyanoalkyl)amino (generic) (P-07-537).

Code of Federal Regulations, 2013 CFR

2013-07-01

... with N100 (if oil aerosols absent), R100, or P100 filters; NIOSH-certified powered air-purifying respirator equipped with a loose- fitting hood or helmet and high efficiency particulate air (HEPA) filters... HEPA filters; or NIOSH-certified supplied-air respirator operated in pressure demand or continuous flow...

40 CFR 721.10411 - Alkanenitrile, bis(cyanoalkyl)amino (generic) (P-07-537).

Code of Federal Regulations, 2014 CFR

2014-07-01

... with N100 (if oil aerosols absent), R100, or P100 filters; NIOSH-certified powered air-purifying respirator equipped with a loose- fitting hood or helmet and high efficiency particulate air (HEPA) filters... HEPA filters; or NIOSH-certified supplied-air respirator operated in pressure demand or continuous flow...

Summary of efficiency testing of standard and high-capacity high-efficiency particulate air filters subjected to simulated tornado depressurization and explosive shock waves

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

Smith, P.R.; Gregory, W.S.

1985-04-01

Pressure transients in nuclear facility air cleaning systems can originate from natural phenomena such as tornadoes or from accident-induced explosive blast waves. This study was concerned with the effective efficiency of high-efficiency particulate air (HEPA) filters during pressure surges resulting from simulated tornado and explosion transients. The primary objective of the study was to examine filter efficiencies at pressure levels below the point of structural failure. Both standard and high-capacity 0.61-m by 0.61-m HEPA filters were evaluated, as were several 0.2-m by 0.2-m HEPA filters. For a particular manufacturer, the material release when subjected to tornado transients is the samemore » (per unit area) for both the 0.2-m by 0.2-m and the 0.61-m by 0.61-m filters. For tornado transients, the material release was on the order of micrograms per square meter. When subjecting clean HEPA filters to simulated tornado transients with aerosol entrained in the pressure pulse, all filters tested showed a degradation of filter efficiency. For explosive transients, the material release from preloaded high-capacity filters was as much as 340 g. When preloaded high-capacity filters were subjected to shock waves approximately 50% of the structural limit level, 1 to 2 mg of particulate was released.« less

40 CFR 721.10077 - 3H-1,2,4-Triazol-3-one, 1,2-dihydro-.

Code of Federal Regulations, 2011 CFR

2011-07-01

...-fitting respirator equipped with N100 (if aerosols absent), R100, or P100 filters (either half- or full... Efficiency Particulate Air (HEPA) filters; powered air-purifying respirator equipped with a tight-fitting facepiece (either half- or full-face) and HEPA filters; and supplied-air respirator operated in pressure...

40 CFR 721.10077 - 3H-1,2,4-Triazol-3-one, 1,2-dihydro-.

Code of Federal Regulations, 2013 CFR

2013-07-01

...-fitting respirator equipped with N100 (if aerosols absent), R100, or P100 filters (either half- or full... Efficiency Particulate Air (HEPA) filters; powered air-purifying respirator equipped with a tight-fitting facepiece (either half- or full-face) and HEPA filters; and supplied-air respirator operated in pressure...

40 CFR 721.10077 - 3H-1,2,4-Triazol-3-one, 1,2-dihydro-.

Code of Federal Regulations, 2012 CFR

2012-07-01

...-fitting respirator equipped with N100 (if aerosols absent), R100, or P100 filters (either half- or full... Efficiency Particulate Air (HEPA) filters; powered air-purifying respirator equipped with a tight-fitting facepiece (either half- or full-face) and HEPA filters; and supplied-air respirator operated in pressure...

40 CFR 721.10077 - 3H-1,2,4-Triazol-3-one, 1,2-dihydro-.

Code of Federal Regulations, 2014 CFR

2014-07-01

...-fitting respirator equipped with N100 (if aerosols absent), R100, or P100 filters (either half- or full... Efficiency Particulate Air (HEPA) filters; powered air-purifying respirator equipped with a tight-fitting facepiece (either half- or full-face) and HEPA filters; and supplied-air respirator operated in pressure...

Survey of HEPA filter experience

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

Carbaugh, E.H.

1982-07-01

A survey of high efficiency particulate air (HEPA) filter applications and experience at Department of Energy (DOE) sites was conducted to provide an overview of the reasons and magnitude of HEPA filter changeouts and failures. Results indicated that approximately 58% of the filters surveyed were changed out in the three year study period, and some 18% of all filters were changed out more than once. Most changeouts (63%) were due to the existence of a high pressure drop across the filter, indicative of filter plugging. Other reasons for changeout included leak-test failure (15%), preventive maintenance service life limit (13%), suspectedmore » damage (5%) and radiation buildup (4%). Filter failures occurred with approximately 12% of all installed filters. Of these failures, most (64%) occurred for unknown or unreported reasons. Handling or installation damage accounted for an additional 19% of reported failures. Media ruptures, filter-frame failures and seal failures each accounted for approximately 5 to 6% of the reported failures.« less

ASME AG-1 Section FC Qualified HEPA Filters; a Particle Loading Comparison - 13435

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

Stillo, Andrew; Ricketts, Craig I.

High Efficiency Particulate Air (HEPA) Filters used to protect personnel, the public and the environment from airborne radioactive materials are designed, manufactured and qualified in accordance with ASME AG-1 Code section FC (HEPA Filters) [1]. The qualification process requires that filters manufactured in accordance with this ASME AG-1 code section must meet several performance requirements. These requirements include performance specifications for resistance to airflow, aerosol penetration, resistance to rough handling, resistance to pressure (includes high humidity and water droplet exposure), resistance to heated air, spot flame resistance and a visual/dimensional inspection. None of these requirements evaluate the particle loading capacitymore » of a HEPA filter design. Concerns, over the particle loading capacity, of the different designs included within the ASME AG-1 section FC code[1], have been voiced in the recent past. Additionally, the ability of a filter to maintain its integrity, if subjected to severe operating conditions such as elevated relative humidity, fog conditions or elevated temperature, after loading in use over long service intervals is also a major concern. Although currently qualified HEPA filter media are likely to have similar loading characteristics when evaluated independently, filter pleat geometry can have a significant impact on the in-situ particle loading capacity of filter packs. Aerosol particle characteristics, such as size and composition, may also have a significant impact on filter loading capacity. Test results comparing filter loading capacities for three different aerosol particles and three different filter pack configurations are reviewed. The information presented represents an empirical performance comparison among the filter designs tested. The results may serve as a basis for further discussion toward the possible development of a particle loading test to be included in the qualification requirements of ASME AG-1 Code sections FC and FK[1]. (authors)« less

Health hazards associated with the use of di-(2-ethylhexyl) phthalate (commonly referred to as DOP) in HEPA filter test

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

NONE

1995-01-01

Di-(2-ethylhexyl) phthalate (DEHP), commonly referred to as di-octyl phthalate, is an important production chemical in the US. In addition to its major use as an additive in plastics, DEHP is widely used to evaluate the effectiveness of high efficiency particulate air (HEPA) filters. Historically, DEHP was also used in quantitative fit testing for respirators. Evaluations of this compound a decade ago showed that it can induce hepatocellular carcinomas in laboratory animals. Although most Department of Energy (DOE) facilities have since discontinued using DEHP in respirator fit testing, DEHP continues to be used for evaluating HEPA filters. This report summarizes availablemore » information on the toxicity, mutagenicity, carcinogenicity, and other hazards and problems posed by DEHP, specifically with reference to HEPA filter testing. Information on work practice improvements as well as the availability and suitability of DEHP substitutes are also presented. This material should assist the DOE in the safe use of this material.« less

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

NASA Astrophysics Data System (ADS)

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 30×30×29cm3 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 1.5to12standardm3/min. Relative humidity levels are controllable from 5%-90% and the temperature of the aerosol stream is variable from ambient to 150°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 7standardm3/min, high mass concentrations (˜25mg/m3) of dry aerosol streams having count mean diameters centered near the most penetrating particle size for HEPA filters (120-160nm). 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.

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.

Further evaluation of alternative air-filtration systems for reducing the transmission of Porcine reproductive and respiratory syndrome virus by aerosol

PubMed Central

Deen, John; Cano, Jean Paul; Batista, Laura; Pijoan, Carlos

2006-01-01

Abstract The purpose of this study was to compare 4 methods for the reduction of aerosol transmission of Porcine reproductive and respiratory syndrome virus (PRRSV): high-efficiency particulate air (HEPA) filtration, 2×-low-cost filtration, bag filtration, and use of a filter tested against particles derived from dioctylphthalate (DOP). The HEPA-filtration system used a prefilter screen, a bag filter (Eurovent [EU] 8 rating), and a HEPA filter (EU13 rating). The low-cost-filtration system contained mosquito netting (prefilter), 2 fiberglass furnace filters, and 2 electrostatic furnace filters. Bag filtration involved the use of a filter rated EU8 and a minimum efficiency reporting value (MERV) of 14. The 95%-DOP, 0.3-μm-filtration system involved a pleat-in-pleat V-bank disposable filter with a 95% efficiency rating for particles 0.3 μm or greater in diameter and ratings of EU9 and MERV 15. No form of intervention was used in the control group. The experimental facilities consisted of 2 chambers connected by a 1.3-m-long duct containing the treatments. Recipient pigs, housed in chamber 2, were exposed to artificial aerosols created by a mechanically operated mister containing modified live PRRSV vaccine located in chamber 1. Aerosol transmission of PRRSV occurred in 0 of the 10 HEPA-filtration replicates, 2 of the 10 bag-filtration replicates, 4 of the 10 low-cost-filtration replicates, 0 of the 10 95%-DOP, 0.3-μm-filtration replicates, and all 10 of the control replicates. Using a similar approach, we further evaluated the HEPA- and 95%-DOP, 0.3-μm-filtration systems. Infection was not observed in any of the 76 HEPA-filtration replicates but was observed in 2 of the 76 95%-DOP, 0.3-μm replicates and 42 of the 50 control replicates. Although the difference between the 95%-DOP, 0.3-μm and control replicates was significant (P < 0.0005), so was the level of failure of the 95%-DOP, 0.3-μm system (P = 0.02). In conclusion, under the conditions of this study, some methods of air filtration were significantly better than others in reducing aerosol transmission of PRRSV, and HEPA filtration was the only system that completely prevented transmission. PMID:16850938

Submicron and Nanoparticulate Matter Removal by HEPA-Rated Media Filters and Packed Beds of Granular Materials

NASA Technical Reports Server (NTRS)

Perry, J. L.; Agui, J. H.; Vijayakimar, R

2016-01-01

Contaminants generated aboard crewed spacecraft by diverse sources consist of both gaseous chemical contaminants and particulate matter. Both HEPA media filters and packed beds of granular material, such as activated carbon, which are both commonly employed for cabin atmosphere purification purposes have efficacy for removing nanoparticulate contaminants from the cabin atmosphere. The phenomena associated with particulate matter removal by HEPA media filters and packed beds of granular material are reviewed relative to their efficacy for removing fine (less than 2.5 micrometers) and ultrafine (less than 0.01 micrometers) sized particulate matter. Considerations are discussed for using these methods in an appropriate configuration to provide the most effective performance for a broad range of particle sizes including nanoparticulates.

Method of treating contaminated HEPA filter media in pulp process

DOEpatents

Hu, Jian S.; Argyle, Mark D.; Demmer, Ricky L.; Mondok, Emilio P.

2003-07-29

A method for reducing contamination of HEPA filters with radioactive and/or hazardous materials is described. The method includes pre-processing of the filter for removing loose particles. Next, the filter medium is removed from the housing, and the housing is decontaminated. Finally, the filter medium is processed as pulp for removing contaminated particles by physical and/or chemical methods, including gravity, flotation, and dissolution of the particles. The decontaminated filter medium is then disposed of as non-RCRA waste; the particles are collected, stabilized, and disposed of according to well known methods of handling such materials; and the liquid medium in which the pulp was processed is recycled.

Impact of humidification and nebulization during expiratory limb protection: an experimental bench study.

PubMed

Tonnelier, Alexandre; Lellouche, François; Bouchard, Pierre Alexandre; L'Her, Erwan

2013-08-01

Different filtering devices are used during mechanical ventilation to avoid dysfunction of flow and pressure transducers or for airborne microorganisms containment. Water condensates, resulting from the use of humidifiers, but also residual nebulization particles may have a major influence on expiratory limb resistance. To evaluate the influence of nebulization and active humidification on the resistance of expiratory filters. A respiratory system analog was constructed using a test lung, an ICU ventilator, heated humidifiers, and a piezoelectric nebulizer. Humidifiers were connected to different types of circuits (unheated, mono-heated, new-generation and old-generation bi-heated). Five filter types were evaluated: electrostatic, heat-and-moisture exchanger, standard, specific, and internal heated high-efficiency particulate air [HEPA] filter. Baseline characteristics were obtained from each dry filter. Differential pressure measurements were carried out after 24 hours of continuous in vitro use for each condition, and after 24 hours of use with an old-generation bi-heated circuit without nebulization. While using unheated circuits, measurements had to be interrupted before 24 hours for all the filtering devices except the internal heated HEPA filter. The heat-and-moisture exchangers occluded before 24 hours with the unheated and mono-heated circuits. The circuit type, nebulization practice, and duration of use did not influence the internal heated HEPA filter resistance. Expiratory limb filtration is likely to induce several major adverse events. Expiratory filter resistance increase is due mainly to the humidification circuit type, rather than to nebulization. If filtration is mandatory while using an unheated circuit, a dedicated filter should be used for ≤ 24 hours, or a heated HEPA for a longer duration.

Flowrate testing of the bag filter LANCS-BOP 6CPVC-1.5-2SPVC (LANCS Industries) at 1 psig

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

Moore, Murray E.; Currie, Karissa Lyn; Berg, Charlotte Katherine

2016-09-13

The air flowrate through a flexible HEPA grade filter (Part LANCS-BOP 6CPVC-1.5-2SPVC www.lancsindustries.com) was measured at 48 ALPM for a differential pressure drop of 1.0 psig (28 inWC, 7.0 kPa). These filters are rated by the manufacturer to have a flowrate of 3 ALPM at a differential pressure drop of 1 inWC (0.25 kPa). The Los Alamos National Laboratory Aerosol Engineering Facility used one of their test rigs (originally developed to measure the pressure drop in capsule HEPA filters) to measure the airflow through the LANCS bag filter.

Combined use of an electrostatic precipitator and a high-efficiency particulate air filter in building ventilation systems: Effects on cardiorespiratory health indicators in healthy adults.

PubMed

Day, D B; Xiang, J; Mo, J; Clyde, M A; Weschler, C J; Li, F; Gong, J; Chung, M; Zhang, Y; Zhang, J

2018-05-01

High-efficiency particulate air (HEPA) filtration in combination with an electrostatic precipitator (ESP) can be a cost-effective approach to reducing indoor particulate exposure, but ESPs produce ozone. The health effect of combined ESP-HEPA filtration has not been examined. We conducted an intervention study in 89 volunteers. At baseline, the air-handling units of offices and residences for all subjects were comprised of coarse, ESP, and HEPA filtration. During the 5-week long intervention, the subjects were split into 2 groups, 1 with just the ESP removed and the other with both the ESP and HEPA removed. Each subject was measured for cardiopulmonary risk indicators once at baseline, twice during the intervention, and once 2 weeks after baseline conditions were restored. Measured indoor and outdoor PM 2.5 and ozone concentrations, coupled with time-activity data, were used to calculate exposures. Removal of HEPA filters increased 24-hour mean PM 2.5 exposure by 38 (95% CI: 31, 45) μg/m 3 . Removal of ESPs decreased 24-hour mean ozone exposure by 2.2 (2.0, 2.5) ppb. No biomarkers were significantly associated with HEPA filter removal. In contrast, ESP removal was associated with a -16.1% (-21.5%, -10.4%) change in plasma-soluble P-selectin and a -3.0% (-5.1%, -0.8%) change in systolic blood pressure, suggesting reduced cardiovascular risks. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Results from Evaluation of Representative ASME AG-1 Section FK Radial Flow Dimple Pleated HEPA Filters Under Elevated Conditions - 12002

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

Giffin, Paxton K.; Parsons, Michael S.; Rickert, Jaime G.

The American Society of Mechanical Engineers (ASME) has recently added Section FK establishing requirements for radial flow HEPA filters to the Code on Nuclear Air and Gas Treatment (AG-1). Section FK filters are expected to be a major element in the HEPA filtration systems across the US Department of Energy (DOE) complex. Radial flow filters have been used in Europe for some time, however a limited amount of performance evaluation data exists with respect to these new AG-1 Section FK units. In consultation with a technical working group, the Institute for Clean Energy Technology (ICET) at Mississippi State University (MSU)hasmore » evaluated a series of representative AG-1 Section FK dimple pleated radial flow HEPA filters. The effects of elevated relative humidity and temperature conditions on these filters are particularly concerning. Results from the evaluation of Section FK filters under ambient conditions have been presented at the 2011 waste management conference. Additions to the previous test stand to enable high temperature and high humidity testing, a review of the equipment used, the steps taken to characterize the new additions, and the filter test results are presented in this study. Test filters were evaluated at a volumetric flow rate of 56.6 m{sup 3}/min (2000 cfm) and were challenged under ambient conditions with Alumina, Al(OH){sub 3}, until reaching a differential pressure of 1 kPa (4 in. w.c.), at which time the filters were tested, unchallenged with aerosol, at 54 deg. C (130 deg. F) for approximately 1 hour. At the end of that hour water was sprayed near the heat source to maximize vaporization exposing the filter to an elevated relative humidity up to 95%. Collected data include differential pressure, temperature, relative humidity, and volumetric flow rate versus time. (authors)« less

Performance Evaluation of Axial Flow AG-1 FC and Prototype FM (High Strength) HEPA Filters - 13123

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

Giffin, Paxton K.; Parsons, Michael S.; Wilson, John A.

High efficiency particulate air (HEPA) filters are routinely used in DOE nuclear containment activities. The Nuclear Air Cleaning Handbook (NACH) stipulates that air cleaning devices and equipment used in DOE nuclear applications must meet the American Society of Mechanical Engineers (ASME) Code on Nuclear Air and Gas Treatment (AG-1) standard. This testing activity evaluates two different axial flow HEPA filters, those from AG-1 Sections FC and FM. Section FM is under development and has not yet been added to AG-1 due to a lack of qualification data available for these filters. Section FC filters are axial flow units that utilizemore » a fibrous glass filtering medium. The section FM filters utilize a similar fibrous glass medium, but also have scrim backing. The scrim-backed filters have demonstrated the ability to endure pressure impulses capable of completely destroying FC filters. The testing activities presented herein will examine the total lifetime loading for both FC and FM filters under ambient conditions and at elevated conditions of temperature and relative humidity. Results will include loading curves, penetration curves, and testing condition parameters. These testing activities have been developed through collaborations with representatives from the National Nuclear Security Administration (NNSA), DOE Office of Environmental Management (DOE-EM), New Mexico State University, and Mississippi State University. (authors)« less

Particulate generation and control in the PREPP (Process Experimental Pilot Plant) incinerator

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

Stermer, D.L.; Gale, L.G.

1989-03-01

Particulate emissions in radioactive incineration systems using a wet scrubbing system are generally ultimately controlled by flowing the process offgas stream through a high-efficiency filter, such as a High Efficient Particulate Air (HEPA) filter. Because HEPA filters are capable of reducing particulate emissions over an order of magnitude below regulatory limits, they consequently are vulnerable to high loading rates. This becomes a serious handicap in radioactive systems when filter change-out is required at an unacceptably high rate. The Process Experimental Pilot Plant (PREPP) incineration system is designed for processing retrieved low level mixed hazardous waste. It has a wet offgasmore » treatment system consisting of a Quencher, Venturi Scrubber, Entrainment Eliminator, Mist Eliminator, two stages of HEPA filters, and induced draft fans. During previous tests, it was noted that the offgas filters loaded with particulate at a rate requiring replacement as often as every four hours. During 1988, PREPP conducted a series of tests which included an investigation of the causes of heavy particulate accumulation on the offgas filters in relation to various operating parameters. This was done by measuring the particulate concentrations in the offgas system, primarily as a function of scrub solution salt concentration, waste feed rate, and offgas flow rate. 2 figs., 9 tabs.« less

Infiltration of forest fire and residential wood smoke: an evaluation of air cleaner effectiveness.

PubMed

Barn, Prabjit; Larson, Timothy; Noullett, Melanie; Kennedy, Susan; Copes, Ray; Brauer, Michael

2008-09-01

Communities impacted by fine-particle air pollution (particles with an aerodynamic diameter less than 2.5 microm; PM(2.5)) from forest fires and residential wood burning require effective, evidence-based exposure-reduction strategies. Public health recommendations during smoke episodes typically include advising community members to remain indoors and the use of air cleaners, yet little information is available on the effectiveness of these measures. Our study attempted to address the following objectives: to measure indoor infiltration factor (F(inf)) of PM(2.5) from forest fires/wood smoke, to determine the effectiveness of high-efficiency particulate air (HEPA) filter air cleaners in reducing indoor PM(2.5), and to analyze the home determinants of F(inf) and air cleaner effectiveness (ACE). We collected indoor/outdoor 1-min PM(2.5) averages and 48-h outdoor PM(2.5) filter samples for 21 winter and 17 summer homes impacted by wood burning and forest fire smoke, respectively, during 2004-2005. A portable HEPA filter air cleaner was operated indoors with the filter removed for one of two sampling days. Particle F(inf) and ACE were calculated for each home using a recursive model. We found mean F(inf)+/-SD was 0.27+/-0.18 and 0.61+/-0.27 in winter (n=19) and summer (n=13), respectively, for days when HEPA filters were not used. Lower F(inf)+/-SD values of 0.10+/-0.08 and 0.19+/-0.20 were found on corresponding days when HEPA filters were in place. Mean+/-SD ACE ([F(inf) without filter-F(inf) with filter]/F(inf) without filter) in winter and summer were 55+/-38% and 65+/-35%, respectively. Number of windows and season predicted F(inf) (P<0.001). No significant predictors of ACE were identified. Our findings show that remaining indoors combined with use of air cleaner can effectively reduce PM(2.5) exposure during forest fires and residential wood burning.

Efficacy of photocatalytic HEPA filter on microorganism removal.

PubMed

Chuaybamroong, P; Chotigawin, R; Supothina, S; Sribenjalux, P; Larpkiattaworn, S; Wu, C-Y

2010-06-01

This study assessed the application of photocatalytic oxidation (PCO) to the high efficiency particulate air (HEPA) filter for disinfection of airborne microorganisms. Experiments were conducted at two TiO2 loadings (1870 +/- 169 and 3140 +/- 67 mg/m(2)) on the HEPA filter irradiated with UV-A at the intensity of 0.85 +/- 0.18 or 4.85 +/- 0.09 mW/cm(2) under two relative humidity conditions (45 +/- 5% and 75 +/- 5%). Inactivation and penetration of four microorganisms were tested, including Aspergillus niger, Penicillium citrinum, Staphylococcus epidermidis, and Bacillus subtilis. It was found that microorganisms retained on a photocatalytic filter were inactivated around 60-80% and even 100% for S. epidermidis when the PCO reactions occurred. Lower penetration was also found from the photocatalytic filter for all airborne microorganisms. High humidity decreased photocatalysis efficacy. Increasing TiO2 loading or irradiance intensity did not substantially affect its disinfection capability. The high efficiency particulate air filter is used widely to remove particulates and microorganisms from the air stream. However, the filter may become a source of microbes if those retained microorganisms proliferate and re-entrain back into the filtered air. This study demonstrates that such a problem can be handled effectively by using photocatalytic reactions to inactivate those confined microorganisms. A 60-100% microbe reduction can be achieved for a wide variety of microorganisms to provide better indoor air quality for hospitals, offices, and domestic applications.

A Feasibility Study for the Laboratory Reduction of Low Level Radioactive Wastes

DTIC Science & Technology

1988-04-01

the Los Alamos National Laboratory), pass the off-gases through a quench column, venturi scrubber , packed column. cordenser, de-mi ste-, re-heater...treatment of the off-gas. In addition to HEPA filters, all of the fully developed systems used sore type of scrubber in the exhaust system to remove...considerations shown in the table and the desired use of a muffle furnace with just a HEPA filter for the off-gas (no scrubbers ), only the slow burn ashing

HEPA Help

ERIC Educational Resources Information Center

Rathey, Allen

2006-01-01

Poor indoor air quality in school facilities can detract from the health and productivity of students, teachers and other employees. Asthma--often triggered or aggravated by dust--is the No. 1 cause of chronic absenteeism in schools. Using vacuum cleaners equipped with high-efficiency particulate air (HEPA) filters to clean education institutions…

Transient Heating and Thermomechanical Stress Modeling of Ceramic HEPA Filters

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

Bogle, Brandon; Kelly, James; Haslam, Jeffrey

The purpose of this report is to showcase an initial finite-element analysis model of a ceramic High-Efficiency Particulate (HEPA) Air filter design. Next generation HEPA filter assemblies are being developed at LLNL to withstand high-temperature fire scenarios by use of ceramics and advanced materials. The filters are meant for use in radiological and nuclear facilities, and are required to survive 500°C fires over an hour duration. During such conditions, however, collecting data under varying parameters can be challenging; therefore, a Finite Element Analysis model of the filter was conducted using COMSOL ® Multiphysics to analyze the effects of fire. Finitemore » Element Analysis (FEA) modelling offers several opportunities: researchers can quickly and easily consider impacts of potential design changes, material selection, and flow characterization on filter performance. Specifically, this model provides stress references for the sealant at high temperatures. Modeling of full filter assemblies was deemed inefficient given the computational requirements, so a section of three tubes from the assembly was modeled. The model looked at the transient heating and thermomechanical stress development during a 500°C air flow at 6 CFM. Significant stresses were found at the ceramic-metal interfaces of the filter, and conservative temperature profiles at locations of interest were plotted. The model can be used for the development of sealants that minimize stresses at the ceramic-metal interface. Further work on the model would include the full filter assembly and consider heat losses to make more accurate predictions.« less

Sintered composite medium and filter

DOEpatents

Bergman, Werner

1987-01-01

A particulate filter medium is formed of a sintered composite of 0.5 micron diameter quartz fibers and 2 micron diameter stainless steel fibers. A preferred composition is about 40 vol. % quartz and about 60 vol. % stainless steel fibers. The media is sintered at about 1100.degree. C. to bond the stainless steel fibers into a cage network which holds the quartz fibers. High filter efficiency and low flow resistance are provided by the smaller quartz fibers. High strength is provided by the stainless steel fibers. The resulting media has a high efficiency and low pressure drop similar to the standard HEPA media, with tensile strength at least four times greater, and a maximum operating temperature of about 550.degree. C. The invention also includes methods to form the composite media and a HEPA filter utilizing the composite media. The filter media can be used to filter particles in both liquids and gases.

Sintered composite filter

DOEpatents

Bergman, W.

1986-05-02

A particulate filter medium formed of a sintered composite of 0.5 micron diameter quartz fibers and 2 micron diameter stainless steel fibers is described. Preferred composition is about 40 vol.% quartz and about 60 vol.% stainless steel fibers. The media is sintered at about 1100/sup 0/C to bond the stainless steel fibers into a cage network which holds the quartz fibers. High filter efficiency and low flow resistance are provided by the smaller quartz fibers. High strength is provided by the stainless steel fibers. The resulting media has a high efficiency and low pressure drop similar to the standard HEPA media, with tensile strength at least four times greater, and a maximum operating temperature of about 550/sup 0/C. The invention also includes methods to form the composite media and a HEPA filter utilizing the composite media. The filter media can be used to filter particles in both liquids and gases.

40 CFR 63.11423 - What are the standards and compliance requirements for new and existing sources?

Code of Federal Regulations, 2012 CFR

2012-07-01

... Lead Acid Battery Manufacturing Area Sources Standards and Compliance Requirements § 63.11423 What are.... Fabric filters equipped with a high efficiency particulate air (HEPA) filter or other secondary filter...

40 CFR 63.11423 - What are the standards and compliance requirements for new and existing sources?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Lead Acid Battery Manufacturing Area Sources Standards and Compliance Requirements § 63.11423 What are.... Fabric filters equipped with a high efficiency particulate air (HEPA) filter or other secondary filter...

40 CFR 63.11423 - What are the standards and compliance requirements for new and existing sources?

Code of Federal Regulations, 2011 CFR

2011-07-01

... Lead Acid Battery Manufacturing Area Sources Standards and Compliance Requirements § 63.11423 What are.... Fabric filters equipped with a high efficiency particulate air (HEPA) filter or other secondary filter...

40 CFR 63.11423 - What are the standards and compliance requirements for new and existing sources?

Code of Federal Regulations, 2013 CFR

2013-07-01

... Lead Acid Battery Manufacturing Area Sources Standards and Compliance Requirements § 63.11423 What are.... Fabric filters equipped with a high efficiency particulate air (HEPA) filter or other secondary filter...

40 CFR 63.11423 - What are the standards and compliance requirements for new and existing sources?

Code of Federal Regulations, 2014 CFR

2014-07-01

... Lead Acid Battery Manufacturing Area Sources Standards and Compliance Requirements § 63.11423 What are.... Fabric filters equipped with a high efficiency particulate air (HEPA) filter or other secondary filter...

Fire tests to evaluate the potential fire threat and its effects on HEPA filter integrity in cell ventilation at the Oak Ridge National Laboratory, Building 7920

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

Hasegawa, H.K.; Staggs, K.J.; Doughty, S.M.

1992-12-01

As a result of a DOE (Tiger Team) Technical Safety Appraisal (November 1990) of the Radiochemical Engineering Development Center (REDC), ORNL Building 7920, a number of fire protection concerns were identified. The primary concern was the perceived loss of ventilation system containment due to the thermal destruction and/or breaching of the prefilters and/or high-efficiency particulate air filters (HEPA `s) and the resultant radioactive release to the external environment. The following report describes the results of an extensive fire test program performed by the Fire Research Discipline (FRD) of the Special Projects Division of Lawrence Livermore National Lab (LLNL) and fundedmore » by ORNL to address these concerns. Full scale mock-ups of a REDC hot cell tank pit, adjacent cubicle pit, and associated ventilation system were constructed at LLNL and 13 fire experiments were conducted to specifically answer the questions raised by the Tiger Team. Our primary test plan was to characterize the burning of a catastrophic solvent spill (kerosene) of 40 liters and its effect on the containment ventilation system prefilters and HEPA filters. In conjunction with ORNL and Lockwood Greene we developed a test matrix that assessed the fire performance of the prefilters and HEPA filters; evaluated the fire response of the fiber reinforced plastic (FRP) epoxy ventilation duct work; the response and effectiveness of the fire protection system, the effect of fire in a cubicle on the vessel off-gas (VOG) elbow, and other fire safety questions.« less

Fungal spore concentrations in two haematopoietic stem cell transplantation (HSCT) units containing distinct air control systems.

PubMed

Brun, C P; Miron, D; Silla, L M R; Pasqualotto, A C

2013-04-01

Invasive fungal diseases have emerged as important causes of morbidity and mortality in haematological patients. In this study air samples were collected in two haematopoietic stem cell transplantation (HSCT) units, in which distinct air-control systems were in place. In hospital 1 no high-efficiency particulate air (HEPA) filter was available whereas in hospital 2 HSCT rooms were equipped with HEPA filters, with positive air pressure in relation to the corridor. A total of 117 samples from rooms, toilets and corridors were obtained during December 2009 to January 2011, using a six-stage Andersen sampler. In both hospitals, the concentration of potentially pathogenic fungi in the air was reduced in patients' rooms compared to corridors (P < 0·0001). Despite the presence of a HEPA filter in hospital 2, rooms in both hospitals showed similar concentrations of potentially pathogenic fungi (P = 0·714). These findings may be explained by the implementation of additional protective measures in hospital 1, emphasizing the importance of such measures in protected environments.

HEPA Filter Disposal Write-Up 10/19/16

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

Loll, C.

Process knowledge (PK) collection on HEPA filters is handled via the same process as other waste streams at LLNL. The Field technician or Characterization point of contact creates an information gathering document (IGD) in the IGD database, with input provided from the generator, and submits it for electronic approval. This document is essentially a waste generation profile, detailing the physical, chemical as well as radiological characteristics, and hazards, of a waste stream. It will typically contain a general, but sometimes detailed, description of the work processes which generated the waste. It will contain PK as well as radiological and industrialmore » hygiene analytical swipe results, and any other analytical or other supporting knowledge related to characterization. The IGD goes through an electronic approval process to formalize the characterization and to ensure the waste has an appropriate disposal path. The waste generator is responsible for providing initial process knowledge information, and approves the IGD before it routed to chemical and radiological waste characterization professionals. This is the standard characterization process for LLNL-generated HEPA Filters.« less

Survey of HEPA filter applications and experience at Department of Energy sites

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

Carbaugh, E.H.

1981-11-01

Results indicated that approximately 58% of the filters surveyed were changed out in the 1977 to 1979 study period and some 18% of all filters were changed out more than once. Most changeouts (60%) were due to the existence of a high pressure drop across the filter, indicative of filter plugging. The next most recurrent reasons for changeout and their percentage changeouts were leak test failure (15%) and preventive maintenance service life limit (12%). An average filter service life was calculated to be 3.0 years with a 2.0-year standard deviation. The labor required for filter changeout was calculated as 1.5more » manhours per filter changed. Filter failures occurred with approximately 12% of all installed filters. Most failures (60%) occurred for unknown reasons and handling or installation damage accounted for an additional 20% of all failures. Media ruptures, filter frame failures and seal failures occurred with approximately equal frequency at 5 to 6% each. Subjective responses to the questionnaire indicate problems are: need for improved acid and moisture resistant filters; filters more readily disposable as radioactive waste; improved personnel training in filter handling and installation; and need for pretreatment of air prior to HEPA filtration.« less

CBR/TIC Filter Design and Evaluation

DTIC Science & Technology

2006-12-29

CBR/TIC Filters Aged CK Filter Life Predicitions.................................................................. 29 Figure 30. CBR/TIC Filters...potting adhesive. Neoprene rubber face gaskets are adhered to each end of the particulate filter for airtight sealing. Figure 16. CBR/TIC HEPA...attached with adhesive to the bottom end cover and is spaced by the compression pads on the top end. EPDM foam compression pads are placed on top

A Pollen Primer | NIH MedlinePlus the Magazine

MedlinePlus

... air filters (HEPA) or an electrostatic air filter. Tree Pollen Trees produce pollen earliest, as soon as January in ... distributed miles away. Fewer than 100 kinds of trees cause allergies. Some common ones are catalpa, elm, ...

40 CFR 63.11507 - What are my standards and management practices?

Code of Federal Regulations, 2011 CFR

2011-07-01

... distilled/de-ionized water, water filtration, pre-cleaning of parts to be plated, and thorough rinsing of... emissions from the thermal spraying process and transports the emissions to a water curtain, fabric filter... and transports the emissions to a water curtain, fabric filter, cartridge, or HEPA filter, according...

A Randomized Cross-over Air Filtration Intervention Trial for Reducing Cardiovascular Health Risks in Residents of Public Housing near a Highway

PubMed Central

Padró-Martínez, Luz T.; Owusu, Emmanuel; Reisner, Ellen; Zamore, Wig; Simon, Matthew C.; Mwamburi, Mkaya; Brown, Carrie A.; Chung, Mei; Brugge, Doug; Durant, John L.

2015-01-01

Exposure to traffic-generated ultrafine particles (UFP; particles <100 nm) is likely a risk factor for cardiovascular disease. We conducted a trial of high-efficiency particulate arrestance (HEPA) filtration in public housing near a highway. Twenty residents in 19 apartments living <200 m from the highway participated in a randomized, double-blind crossover trial. A HEPA filter unit and a particle counter (measuring particle number concentration (PNC), a proxy for UFP) were installed in living rooms. Participants were exposed to filtered air for 21 days and unfiltered air for 21 days. Blood samples were collected and blood pressure measured at days 0, 21 and 42 after a 12-hour fasting period. Plasma was analyzed for high sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), tumor necrosis factor alpha-receptor II (TNF-RII) and fibrinogen. PNC reductions ranging from 21% to 68% were recorded in 15 of the apartments. We observed no significant differences in blood pressure or three of the four biomarkers (hsCRP, fibrinogen, and TNF-RII) measured in participants after 21-day exposure to HEPA-filtered air compared to measurements after 21-day exposure to sham-filtered air. In contrast, IL-6 concentrations were significantly higher following HEPA filtration (0.668 pg/mL; CI = 0.465–0.959) compared to sham filtration. Likewise, PNC adjusted for time activity were associated with increasing IL-6 in 14- and 21-day moving averages, and PNC was associated with decreasing blood pressure in Lags 0, 1 and 2, and in a 3-day moving average. These negative associations were unexpected and could be due to a combination of factors including exposure misclassification, unsuccessful randomization (i.e., IL-6 and use of anti-inflammatory medicines), or uncontrolled confounding. Studies with greater reduction in UFP levels and larger sample sizes are needed. There also needs to be more complete assessment of resident time activity and of outdoor vs. indoor source contributions to UFP exposure. HEPA filtration remains a promising, but not fully realized intervention. PMID:26184257

A Randomized Cross-over Air Filtration Intervention Trial for Reducing Cardiovascular Health Risks in Residents of Public Housing near a Highway.

PubMed

Padró-Martínez, Luz T; Owusu, Emmanuel; Reisner, Ellen; Zamore, Wig; Simon, Matthew C; Mwamburi, Mkaya; Brown, Carrie A; Chung, Mei; Brugge, Doug; Durant, John L

2015-07-10

Exposure to traffic-generated ultrafine particles (UFP; particles <100 nm) is likely a risk factor for cardiovascular disease. We conducted a trial of high-efficiency particulate arrestance (HEPA) filtration in public housing near a highway. Twenty residents in 19 apartments living <200 m from the highway participated in a randomized, double-blind crossover trial. A HEPA filter unit and a particle counter (measuring particle number concentration (PNC), a proxy for UFP) were installed in living rooms. Participants were exposed to filtered air for 21 days and unfiltered air for 21 days. Blood samples were collected and blood pressure measured at days 0, 21 and 42 after a 12-hour fasting period. Plasma was analyzed for high sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), tumor necrosis factor alpha-receptor II (TNF-RII) and fibrinogen. PNC reductions ranging from 21% to 68% were recorded in 15 of the apartments. We observed no significant differences in blood pressure or three of the four biomarkers (hsCRP, fibrinogen, and TNF-RII) measured in participants after 21-day exposure to HEPA-filtered air compared to measurements after 21-day exposure to sham-filtered air. In contrast, IL-6 concentrations were significantly higher following HEPA filtration (0.668 pg/mL; CI = 0.465-0.959) compared to sham filtration. Likewise, PNC adjusted for time activity were associated with increasing IL-6 in 14- and 21-day moving averages, and PNC was associated with decreasing blood pressure in Lags 0, 1 and 2, and in a 3-day moving average. These negative associations were unexpected and could be due to a combination of factors including exposure misclassification, unsuccessful randomization (i.e., IL-6 and use of anti-inflammatory medicines), or uncontrolled confounding. Studies with greater reduction in UFP levels and larger sample sizes are needed. There also needs to be more complete assessment of resident time activity and of outdoor vs. indoor source contributions to UFP exposure. HEPA filtration remains a promising, but not fully realized intervention.

Evaluation of the ICET Test Stand to Assess the Performance of a Range of Ceramic Media Filter Elements in Support of ASME AG-1 Subsection FO

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

Schemmel, A.

High Efficiency Particulate Air (HEPA) filters are defined as extended-medium, dry-type filters with: (1) a minimum particle removal efficiency of no less than 99.97 percent for 0.3 micrometer particles, (2) a maximum, clean resistance of 1.0 inch water column (in. WC) when operated at 1,000 cubic feet per minute (CFM), and (3) a rigid casing that extends the full depth of the medium. Specifically, ceramic media HEPA filters provide better performance at elevated temperatures, are moisture resistant and nonflammable, can perform their function if wetted and exposed to greater pressures, and can be cleaned and reused. This paper describes themore » modification and design of a large scale test stand which properly evaluates the filtration characteristics of a range of ceramic media filters challenged with a nuclear aerosol agent in order to develop Section FO of ASME AG-1.« less

40 CFR 63.542 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... to monitor relative particulate matter loadings. Battery breaking area means the plant location at which lead-acid batteries are broken, crushed, or disassembled and separated into components. Blast...) Casting operations occur. High efficiency particulate air (HEPA) filter means a filter that has been...

40 CFR 63.542 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... to monitor relative particulate matter loadings. Battery breaking area means the plant location at which lead-acid batteries are broken, crushed, or disassembled and separated into components. Blast...) Casting operations occur. High efficiency particulate air (HEPA) filter means a filter that has been...

Method of concurrently filtering particles and collecting gases

DOEpatents

Mitchell, Mark A; Meike, Annemarie; Anderson, Brian L

2015-04-28

A system for concurrently filtering particles and collecting gases. Materials are be added (e.g., via coating the ceramic substrate, use of loose powder(s), or other means) to a HEPA filter (ceramic, metal, or otherwise) to collect gases (e.g., radioactive gases such as iodine). The gases could be radioactive, hazardous, or valuable gases.

29 CFR 1926.1127 - Cadmium.

Code of Federal Regulations, 2010 CFR

2010-07-01

... from that process. High-efficiency Particulate Air [HEPA] filter means a filter capable of trapping and...) expected to have the highest cadmium exposures. (2) Specific. (i) Initial monitoring. Except as provided... 1926.354, where applicable. (3) Prohibitions. (i) High speed abrasive disc saws and similar abrasive...

29 CFR 1926.1127 - Cadmium.

Code of Federal Regulations, 2013 CFR

2013-07-01

... from that process. High-efficiency Particulate Air [HEPA] filter means a filter capable of trapping and...) expected to have the highest cadmium exposures. (2) Specific. (i) Initial monitoring. Except as provided... 1926.354, where applicable. (3) Prohibitions. (i) High speed abrasive disc saws and similar abrasive...

29 CFR 1926.1127 - Cadmium.

Code of Federal Regulations, 2014 CFR

2014-07-01

... from that process. High-efficiency Particulate Air [HEPA] filter means a filter capable of trapping and...) expected to have the highest cadmium exposures. (2) Specific. (i) Initial monitoring. Except as provided... 1926.354, where applicable. (3) Prohibitions. (i) High speed abrasive disc saws and similar abrasive...

29 CFR 1926.1127 - Cadmium.

Code of Federal Regulations, 2012 CFR

2012-07-01

... from that process. High-efficiency Particulate Air [HEPA] filter means a filter capable of trapping and...) expected to have the highest cadmium exposures. (2) Specific. (i) Initial monitoring. Except as provided... 1926.354, where applicable. (3) Prohibitions. (i) High speed abrasive disc saws and similar abrasive...

40 CFR 721.10583 - Benzenamine, 4,4′-[1,3-phenylenebis(1-methylethylidene)]bis-.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., tight-fitting half-face respirator equipped with N100 (if oil aerosols absent), R100, or P100 filters... aerosols absent), R100, or P100 filters. (C) NIOSH-certified powered air-purifying respirator equipped with a loose-fitting hood or helmet and high efficiency particulate air (HEPA) filters. (D) NIOSH...

40 CFR 721.10583 - Benzenamine, 4,4′-[1,3-phenylenebis(1-methylethylidene)]bis-.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., tight-fitting half-face respirator equipped with N100 (if oil aerosols absent), R100, or P100 filters... aerosols absent), R100, or P100 filters. (C) NIOSH-certified powered air-purifying respirator equipped with a loose-fitting hood or helmet and high efficiency particulate air (HEPA) filters. (D) NIOSH...

Bacterial communities in commercial aircraft high-efficiency particulate air (HEPA) filters assessed by PhyloChip analysis.

PubMed

Korves, T M; Piceno, Y M; Tom, L M; Desantis, T Z; Jones, B W; Andersen, G L; Hwang, G M

2013-02-01

Air travel can rapidly transport infectious diseases globally. To facilitate the design of biosensors for infectious organisms in commercial aircraft, we characterized bacterial diversity in aircraft air. Samples from 61 aircraft high-efficiency particulate air (HEPA) filters were analyzed with a custom microarray of 16S rRNA gene sequences (PhyloChip), representing bacterial lineages. A total of 606 subfamilies from 41 phyla were detected. The most abundant bacterial subfamilies included bacteria associated with humans, especially skin, gastrointestinal and respiratory tracts, and with water and soil habitats. Operational taxonomic units that contain important human pathogens as well as their close, more benign relatives were detected. When compared to 43 samples of urban outdoor air, aircraft samples differed in composition, with higher relative abundance of Firmicutes and Gammaproteobacteria lineages in aircraft samples, and higher relative abundance of Actinobacteria and Betaproteobacteria lineages in outdoor air samples. In addition, aircraft and outdoor air samples differed in the incidence of taxa containing human pathogens. Overall, these results demonstrate that HEPA filter samples can be used to deeply characterize bacterial diversity in aircraft air and suggest that the presence of close relatives of certain pathogens must be taken into account in probe design for aircraft biosensors. A biosensor that could be deployed in commercial aircraft would be required to function at an extremely low false alarm rate, making an understanding of microbial background important. This study reveals a diverse bacterial background present on aircraft, including bacteria closely related to pathogens of public health concern. Furthermore, this aircraft background is different from outdoor air, suggesting different probes may be needed to detect airborne contaminants to achieve minimal false alarm rates. This study also indicates that aircraft HEPA filters could be used with other molecular techniques to further characterize background bacteria and in investigations in the wake of a disease outbreak. © 2012 John Wiley & Sons A/S.

High Efficiency Particulate Air (HEPA) Filter Generation, Characterization, and Disposal Experiences at the Oak Ridge National Laboratory

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

Coffey, D. E.

2002-02-28

High Efficiency Particulate Air filtration is an essential component of the containment and ventilation systems supporting the research and development activities at the Oak Ridge National Laboratory. High Efficiency Particulate Air filters range in size from 7.6cm (3 inch) by 10.2 cm (4 inch) cylindrical shape filters to filter array assemblies up to 2.1 m (7 feet) high by 1.5 m (5 feet) wide. Spent filters are grouped by contaminates trapped in the filter media and become one of the components in the respective waste stream. Waste minimization and pollution prevention efforts are applied for both radiological and non-radiological applications.more » Radiological applications include laboratory hoods, glove boxes, and hot cells. High Efficiency Particulate Air filters also are generated from intake or pre-filtering applications, decontamination activities, and asbestos abatement applications. The disposal avenues include sanitary/industrial waste, Resource Conservation and Recovery Act and Toxic Substance Control Act, regulated waste, solid low-level waste, contact handled transuranic, and remote handled transuranic waste. This paper discusses characterization and operational experiences associated with the disposal of the spent filters across multiple applications.« less

Protective environment for hematopoietic cell transplant (HSCT) recipients: The Infectious Diseases Working Party EBMT analysis of global recommendations on health-care facilities.

PubMed

Styczynski, Jan; Tridello, Gloria; Donnelly, J Peter; Iacobelli, Simona; Hoek, Jennifer; Mikulska, Malgorzata; Aljurf, Mahmoud; Gil, Lidia; Cesaro, Simone

2018-03-13

International guidelines on protective environment for HSCT recipients proposed a set of 10 global recommendations in 2009 on protective environment (GRPE) concerning hospital room design and ventilation. The EBMT Infectious Diseases Working Party undertook a survey on the status on protective environment for HSCT recipients with the aim of surveying current practices and their agreement with GRPE recommendations. The questionnaire consisted of 37 questions divided into 5 sections about filtration, air changes, maintenance, and the protective environment in rooms and the surrounding unit. Overall, 177 centres (response rate 33%) from 36 countries responded, indicating that 99.4% of patient rooms were equipped with HEPA filters, but only 48.6% of the centre's staff were aware of, and could confirm, regular replacement of filters based on manufacturers' recommendations. Well-sealed rooms were used in terms of windows (70.6%), ceilings (35%), and plumbing pipes (51.4%). The sensor monitors in the patient room used to determine when the HEPA filters require changing were installed only in 18.1% of centres. Only 1 centre fulfilled all 10 GRPE recommendations, while 62 centres fulfilled the 3 level "A" recommendations. In conclusion, HEPA-filtered rooms are available in almost all centres, while fewer centres fulfilled other requirements. Knowledge on the details and maintenance of protective environments in the HSCT setting was inadequate, reflecting a lack of communication between the health personnel involved, hospital infection control and the hospital maintenance services.

Nuclear air cleaning: the need for a change in emphasis

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

Carbaugh, E.H.

1982-11-01

The nuclear industry now has over 35 years of experience in nuclear air cleaning. This experience covers technology development, system design, operations, and maintenance. Much of the past experience has been directed towards technology development with particular emphasis on high efficiency particulate air (HEPA) filters. Implementation of this technology has lagged its development by a number of years. A recent study examines the cause and frequencies of HEPA filter changeouts and failures. These data lead to a conclusion that a shift in emphasis from technology development to the training of personnel and the designing and maintaining of such systems ismore » needed. Some highlights of the data and a discussion of topics which should be addressed in training will be presented.« less

40 CFR 721.10575 - 1-Propanone, 1,1'-(oxydi-4,1-phenylene)bis[2-hydroxy-2-methyl-.

Code of Federal Regulations, 2013 CFR

2013-07-01

...), R100, or P100 filters. (B) NIOSH-certified air-purifying, tight-fitting full-face respirator equipped with N100 (if oil aerosols absent), R100, or P100 filters. (C) NIOSH-certified powered air-purifying respirator equipped with a loose-fitting hood or helmet and high efficiency particulate air (HEPA) filters...

40 CFR 721.10575 - 1-Propanone, 1,1'-(oxydi-4,1-phenylene)bis[2-hydroxy-2-methyl-.

Code of Federal Regulations, 2014 CFR

2014-07-01

...), R100, or P100 filters. (B) NIOSH-certified air-purifying, tight-fitting full-face respirator equipped with N100 (if oil aerosols absent), R100, or P100 filters. (C) NIOSH-certified powered air-purifying respirator equipped with a loose-fitting hood or helmet and high efficiency particulate air (HEPA) filters...

Comparison of home lead dust reduction techniques on hard surfaces: the New Jersey assessment of cleaning techniques trial.

PubMed Central

Rich, David Q; Rhoads, George G; Yiin, Lih-Ming; Zhang, Junfeng; Bai, Zhipeng; Adgate, John L; Ashley, Peter J; Lioy, Paul J

2002-01-01

High efficiency particulate air filter (HEPA) vacuums, which collect particles > 0.3 micro m, and trisodium phosphate (TSP), a detergent claimed to selectively remove lead, have been included in the HUD Guidelines for the Evaluation and Control of Lead Based Paint Hazards in Housing without systematic validation of their effectiveness. At the time the study was initiated, both HEPA vacuums and TSP were relatively expensive, they were not readily found in urban retail centers, and there were environmental concerns about the use and disposal of high-phosphate detergents. A randomized, controlled trial was conducted in urban high-risk homes in northern New Jersey to determine whether a more readily available and less expensive low-phosphate, non-TSP detergent and non-HEPA vacuum could perform as well as TSP and a HEPA vacuum in a cleaning protocol. Homes were randomized to one of three cleaning methods: TSP/HEPA vacuum, TSP/non-HEPA vacuum, or non-TSP/non-HEPA vacuum. Change in log-transformed lead loading was used in mixed models to compare the efficacy of the three cleaning techniques separately for uncarpeted floors, window sills, and window troughs. After we adjusted for baseline lead loading, the non-HEPA vacuum produced larger reductions on hard floors [19%; 95% confidence interval (CI), 3-38%], but the HEPA vacuum produced larger reductions on window sills (22%; 95% CI, 11-32%) and larger reductions on window troughs (16%; 95% CI, -4 to 33%). The non-TSP produced larger reductions on window troughs (21%; 95% CI, -2 to 50%), but TSP produced larger reductions on hard floors (5%; 95% CI, -12 to 19%) and window sills (8%; 95% CI, -5 to 20%). TSP/HEPA produced larger reductions on window sills (28%; 95% CI, 18-37%) and larger reductions on window troughs (2%; 95% CI, -24 to 23%), whereas the non-TSP/non-HEPA method produced larger reductions on hard floors (13%; 95% CI, -5 to 34%). Because neither vacuum nor detergent produced consistent results across surface types, the use of low-phosphate detergents and non-HEPA vacuums in a temporary control measure is supported. PMID:12204823

Comparison of home lead dust reduction techniques on hard surfaces: the New Jersey assessment of cleaning techniques trial.

PubMed

Rich, David Q; Rhoads, George G; Yiin, Lih-Ming; Zhang, Junfeng; Bai, Zhipeng; Adgate, John L; Ashley, Peter J; Lioy, Paul J

2002-09-01

High efficiency particulate air filter (HEPA) vacuums, which collect particles > 0.3 micro m, and trisodium phosphate (TSP), a detergent claimed to selectively remove lead, have been included in the HUD Guidelines for the Evaluation and Control of Lead Based Paint Hazards in Housing without systematic validation of their effectiveness. At the time the study was initiated, both HEPA vacuums and TSP were relatively expensive, they were not readily found in urban retail centers, and there were environmental concerns about the use and disposal of high-phosphate detergents. A randomized, controlled trial was conducted in urban high-risk homes in northern New Jersey to determine whether a more readily available and less expensive low-phosphate, non-TSP detergent and non-HEPA vacuum could perform as well as TSP and a HEPA vacuum in a cleaning protocol. Homes were randomized to one of three cleaning methods: TSP/HEPA vacuum, TSP/non-HEPA vacuum, or non-TSP/non-HEPA vacuum. Change in log-transformed lead loading was used in mixed models to compare the efficacy of the three cleaning techniques separately for uncarpeted floors, window sills, and window troughs. After we adjusted for baseline lead loading, the non-HEPA vacuum produced larger reductions on hard floors [19%; 95% confidence interval (CI), 3-38%], but the HEPA vacuum produced larger reductions on window sills (22%; 95% CI, 11-32%) and larger reductions on window troughs (16%; 95% CI, -4 to 33%). The non-TSP produced larger reductions on window troughs (21%; 95% CI, -2 to 50%), but TSP produced larger reductions on hard floors (5%; 95% CI, -12 to 19%) and window sills (8%; 95% CI, -5 to 20%). TSP/HEPA produced larger reductions on window sills (28%; 95% CI, 18-37%) and larger reductions on window troughs (2%; 95% CI, -24 to 23%), whereas the non-TSP/non-HEPA method produced larger reductions on hard floors (13%; 95% CI, -5 to 34%). Because neither vacuum nor detergent produced consistent results across surface types, the use of low-phosphate detergents and non-HEPA vacuums in a temporary control measure is supported.

Particulate matter concentrations in residences: an intervention study evaluating stand-alone filters and air conditioners

PubMed Central

Batterman, S.; Du, L.; Mentz, G.; Mukherjee, B.; Parker, E.; Godwin, C.; Chin, J.-Y.; O'Toole, A.; Robins, T.; Rowe, Z.; Lewis, T.

2014-01-01

This study, a randomized controlled trial, evaluated the effectiveness of free-standing air filters and window air conditioners (ACs) in 126 low-income households of children with asthma. Households were randomized into a control group, a group receiving a free-standing HEPA filter placed in the child's sleeping area, and a group receiving the filter and a window-mounted AC. Indoor air quality (IAQ) was monitored for week-long periods over three to four seasons. High concentrations of particulate matter (PM) and carbon dioxide were frequently seen. When IAQ was monitored, filters reduced PM levels in the child's bedroom by an average of 50%. Filter use varied greatly among households and declined over time, for example, during weeks when pollutants were monitored, filter use was initially high, averaging 84 ± 27%, but dropped to 63 ± 33% in subsequent seasons. In months when households were not visited, use averaged only 34 ± 30%. Filter effectiveness did not vary in homes with central or room ACs. The study shows that measurements over multiple seasons are needed to characterize air quality and filter performance. The effectiveness of interventions using free-standing air filters depends on occupant behavior, and strategies to ensure filter use should be an integral part of interventions. PMID:22145709

Preparing cytotoxic agents in an isolator.

PubMed

Favier, M; Hansel, S; Bressolle, F

1993-11-01

The design of an isolator and its use by an oncology satellite pharmacy for preparing cytotoxic drugs are described. The isolator (Iso Concept, Boulogne, France) is a totally enclosed ventilated biological-safety cabinet of class III polyvinyl chloride (PVC) with positive air pressure, a half-suit with a rotating seal, and attached neoprene gloves. There are three work-stations, one for the half-suit and two along one side of the isolator. The ventilation and air filtration system consists of one entry pipe with a full ventilation-filtration box fitted with one prefilter, one blower, one ball valve, one high-efficiency particulate air (HEPA) filter, one airtight nipple connected to an automatic sterilizer, alarms, and one exhaust pipe protected by a HEPA filter. The air lock consists of a rigid, transparent Plexiglas pass-through. The chamber is sterilized with heated compressed air mixed with 3.5% peracetic acid. Maintenance includes regular changing of gloves and HEPA filters; checking of the integrity of the PVC, half-suit, and gloves; and washing and decontamination procedures. Preparation of cytotoxics is planned in advance with prescription data and manufacturing sheets. In the half-suit, a pharmacy technician reads the label, supervises preparation of the sterile admixture, and writes a label. The operators on the side of the unit read the manufacturing sheet and prepare the dose identified by the label.(ABSTRACT TRUNCATED AT 250 WORDS)

Advanced Filter Technology For Nuclear Thermal Propulsion

NASA Technical Reports Server (NTRS)

Castillon, Erick

2015-01-01

The Scrubber System focuses on using HEPA filters and carbon filtration to purify the exhaust of a Nuclear Thermal Propulsion engine of its aerosols and radioactive particles; however, new technology may lend itself to alternate filtration options, which may lead to reduction in cost while at the same time have the same filtering, if not greater, filtering capabilities, as its predecessors. Extensive research on various types of filtration methods was conducted with only four showing real promise: ionization, cyclonic separation, classic filtration, and host molecules. With the four methods defined, more research was needed to find the devices suitable for each method. Each filtration option was matched with a device: cyclonic separators for the method of the same name, electrostatic separators for ionization, HEGA filters, and carcerands for the host molecule method. Through many hours of research, the best alternative for aerosol filtration was determined to be the electrostatic precipitator because of its high durability against flow rate and its ability to cleanse up to 99.99% of contaminants as small as 0.001 micron. Carcerands, which are the only alternative to filtering radioactive particles, were found to be non-existent commercially because of their status as a "work in progress" at research institutions. Nevertheless, the conclusions after the research were that HEPA filters is recommended as the best option for filtering aerosols and carbon filtration is best for filtering radioactive particles.

40 CFR 721.10002 - 2-Thiazolidinone.

Code of Federal Regulations, 2011 CFR

2011-07-01

... HEPA filters; and supplied-air respirator operated in pressure demand or continuous flow mode and... substance may cause internal organ effects (blood, liver, and kidney). The substance may cause developmental...

40 CFR 721.10002 - 2-Thiazolidinone.

Code of Federal Regulations, 2010 CFR

2010-07-01

... HEPA filters; and supplied-air respirator operated in pressure demand or continuous flow mode and... substance may cause internal organ effects (blood, liver, and kidney). The substance may cause developmental...

The effectiveness of stand alone air cleaners for shelter-in-place.

PubMed

Ward, M; Siegel, J A; Corsi, R L

2005-04-01

Stand-alone air cleaners may be efficient for rapid removal of indoor fine particles and have potential use for shelter-in-place (SIP) strategies following acts of bioterrorism. A screening model was employed to ascertain the potential significance of size-resolved particle (0.1-2 microm) removal using portable high efficiency particle arresting (HEPA) air cleaners in residential buildings following an outdoor release of particles. The number of stand-alone air cleaners, air exchange rate, volumetric flow rate through the heating, ventilating and air-conditioning (HVAC) system, and size-resolved particle removal efficiency in the HVAC filter were varied. The effectiveness of air cleaners for SIP was evaluated in terms of the outdoor and the indoor particle concentration with air cleaner(s) relative to the indoor concentration without air cleaners. Through transient and steady-state analysis of the model it was determined that one to three portable HEPA air cleaners can be effective for SIP following outdoor bioaerosol releases, with maximum reductions in particle concentrations as high as 90% relative to conditions in which an air cleaner is not employed. The relative effectiveness of HEPA air cleaners vs. other removal mechanisms was predicted to decrease with increasing particle size, because of increasing competition by particle deposition with indoor surfaces and removal to HVAC filters. However, the effect of particle size was relatively small for most scenarios considered here. The results of a screening analysis suggest that stand-alone (portable) air cleaners that contain high efficiency particle arresting (HEPA) filters can be effective for reducing indoor fine particle concentrations in residential dwellings during outdoor releases of biological warfare agents. The relative effectiveness of stand-alone air cleaners for reducing occupants' exposure to particles of outdoor origin depends on several factors, including the type of heating, ventilating and air-conditioning (HVAC) filter, HVAC operation, building air exchange rate, particle size, and duration of elevated outdoor particle concentration. Maximum particle reductions, relative to no stand-alone air cleaners, of 90% are predicted when three stand-alone air cleaners are employed.

Development of Test Protocols for International Space Station Particulate Filters

NASA Technical Reports Server (NTRS)

Green, Robert D.; Vijayakumar, R.; Agui, Juan H.

2014-01-01

Air quality control on the International Space Station (ISS) is a vital requirement for maintaining a clean environment for the crew and the hardware. This becomes a serious challenge in pressurized space compartments since no outside air ventilation is possible, and a larger particulate load is imposed on the filtration system due to lack of gravitational settling. The ISS Environmental Control and Life Support System (ECLSS) uses a filtration system that has been in use for over 14 years and has proven to meet this challenge. The heart of this system is a traditional High- Efficiency Particulate Air (HEPA) filter configured to interface with the rest of the life support elements and provide effective cabin filtration. Over the years, the service life of these filters has been re-evaluated based on limited post-flight tests of returned filters and risk factors. On earth, a well designed and installed HEPA filter will last for several years, e.g. in industrial and research clean room applications. Test methods for evaluating these filters are being developed on the basis of established test protocols used by the industry and the military. This paper will discuss the test methods adopted and test results on prototypes of the ISS filters. The results will assist in establishing whether the service life can be extended for these filters. Results from unused filters that have been in storage will also be presented to ascertain the shelf life and performance deterioration, if any and determine if the shelf life may be extended.

Results from Evaluation of Proposed ASME AG-1 Section FI Metal Media Filters - 13063

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

Wilson, John A.; Giffin, Paxton K.; Parsons, Michael S.

High efficiency particulate air (HEPA) filtration technology is commonly used in Department of Energy (DOE) facilities that require control of radioactive particulate matter (PM) emissions due to treatment or management of radioactive materials. Although HEPA technology typically makes use of glass fiber media, metal and ceramic media filters are also capable of filtering efficiencies beyond the required 99.97%. Sintered metal fiber filters are good candidates for use in DOE facilities due to their resistance to corrosive environments and resilience at high temperature and elevated levels of relative humidity. Their strength can protect them from high differential pressure or pressure spikesmore » and allow for back pulse cleaning, extending filter lifetime. Use of these filters has the potential to reduce the cost of filtration in DOE facilities due to life cycle cost savings. ASME AG-1 section FI has not been approved due to a lack of protocols and performance criteria for qualifying section FI filters. The Institute for Clean Energy Technology (ICET) with the aid of the FI project team has developed a Section FI test stand and test plan capable of assisting in the qualification ASME AG-1 section FI filters. Testing done at ICET using the FI test stand evaluates resistance to rated air flow, test aerosol penetration and resistance to heated air of the section FI filters. Data collected during this testing consists of temperature, relative humidity, differential pressure, flow rate, upstream particle concentration, and downstream particle concentration. (authors)« less

Effectiveness of in-room air filtration and dilution ventilation for tuberculosis infection control.

PubMed

Miller-Leiden, S; Lobascio, C; Nazaroff, W W; Macher, J M

1996-09-01

Tuberculosis (TB) is a public health problem that may pose substantial risks to health care workers and others. TB infection occurs by inhalation of airborne bacteria emitted by persons with active disease. We experimentally evaluated the effectiveness of in-room air filtration systems, specifically portable air filters (PAFs) and ceiling-mounted air filters (CMAFs), in conjunction with dilution ventilation, for controlling TB exposure in high-risk settings. For each experiment, a test aerosol was continuously generated and released into a full-sized room. With the in-room air filter and room ventilation system operating, time-averaged airborne particle concentrations were measured at several points. The effectiveness of in-room air filtration plus ventilation was determined by comparing particle concentrations with and without device operation. The four PAFs and three CMAFs we evaluated reduced room-average particle concentrations, typically by 30% to 90%, relative to a baseline scenario with two air-changes per hour of ventilation (outside air) only. Increasing the rate of air flow recirculating through the filter and/or air flow from the ventilation did not always increase effectiveness. Concentrations were generally higher near the emission source than elsewhere in the room. Both the air flow configuration of the filter and its placement within the room were important, influencing room air flow patterns and the spatial distribution of concentrations. Air filters containing efficient, but non-high efficiency particulate air (HEPA) filter media were as effective as air filters containing HEPA filter media.

Effectiveness of In-Room Air Filtration and Dilution Ventilation for Tuberculosis Infection Control.

PubMed

Miller-Leiden, S; Lohascio, C; Nazaroff, W W; Macher, J M

1996-09-01

Tuberculosis (TB) is a public health problem that may pose substantial risks to health care workers and others. TB infection occurs by inhalation of airborne bacteria emitted by persons with active disease. We experimentally evaluated the effectiveness of in-room air filtration systems, specifically portable air filters (PAFs) and ceiling-mounted air filters (CMAFs), in conjunction with dilution ventilation, for controlling TB exposure in high-risk settings. For each experiment, a test aerosol was continuously generated and released into a full-sized room. With the in-room air filter and room ventilation system operating, time-averaged airborne particle concentrations were measured at several points. The effectiveness of in-room air filtration plus ventilation was determined by comparing particle concentrations with and without device operation. The four PAFs and three CMAFs we evaluated reduced room-average particle concentrations, typically by 30% to 90%, relative to a baseline scenario with two air-changes per hour of ventilation (outside air) only. Increasing the rate of air flow recirculating through the filter and/or air flow from the ventilation did not always increase effectiveness. Concentrations were generally higher near the emission source than elsewhere in the room. Both the air flow configuration of the filter and its placement within the room were important, influencing room air flow patterns and the spatial distribution of concentrations. Air filters containing efficient, but non-high efficiency particulate air (HEPA) filter media were as effective as air filters containing HEPA filter media.

Effects of MERV 16 filters and routine work practices on enclosed cabs for reducing respirable dust and DPM exposures in an underground limestone mine

PubMed Central

Noll, J.D.; Cecala, A.B.; J.A.Organiscak; Rider, J.P.

2015-01-01

An effective technique to minimize miners’ respirable dust and diesel exposure on mobile mining equipment is to place mine operators in enclosed cabs with designed filtration and pressurization systems. Many factors affect the performance of these enclosed cab systems, and one of the most significant factors is the effectiveness of the filtration system. High-efficiency particulate air (HEPA)-type filters are typically used because they are highly efficient at capturing all types and sizes of particles, including those in the submicron range such as diesel particulate matter (DPM). However, in laboratory tests, minimum efficiency reporting value (MERV) 16 filters have proven to be highly efficient for capturing DPM and respirable dust. Also, MERV 16 filters can be less restrictive to cab airflow and less expensive than HEPA filters. To verify their effectiveness in the field, MERV 16 filters were used in the enclosed cab filtration system on a face drill and roof bolting mining machine and tested at an underground limestone mine. Test results showed that DPM and respirable dust concentrations were reduced by more than 90% when the cabs were properly sealed. However, when the cab door was opened periodically throughout the shift, the reduction efficiency of the MERV 16 filters was reduced to 80% on average. PMID:26236044

Air filtration in the free molecular flow regime: a review of high-efficiency particulate air filters based on carbon nanotubes.

PubMed

Li, Peng; Wang, Chunya; Zhang, Yingying; Wei, Fei

2014-11-01

Air filtration in the free molecular flow (FMF) regime is important and challenging because a higher filtration efficiency and lower pressure drop are obtained when the fiber diameter is smaller than the gas mean free path in the FMF regime. In previous studies, FMF conditions have been obtained by increasing the gas mean free path through reducing the pressure and increasing the temperature. In the case of carbon nanotubes (CNTs) with nanoscale diameters, it is possible to filtrate in the FMF regime under normal conditions. This paper reviews recent progress in theoretical and experimental studies of air filtration in the FMF regime. Typical structure models of high-efficiency particulate (HEPA) air filters based on CNTs are introduced. The pressure drop in air filters operated in the FMF regime is less than that predicted by the conventional air filtration theory. The thinnest HEPA filters fabricated from single-walled CNT films have an extremely low pressure drop. CNT air filters with a gradient nanostructure are shown to give a much better filtration performance in dynamic filtration. CNT air filters with a hierarchical structure and an agglomerated CNT fluidized bed air filter are also introduced. Finally, the challenges and opportunities for the application of CNTs in air filtration are discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of ceiling-mounted HEPA-UV air filters on airborne bacteria concentrations in an indoor therapy pool building.

PubMed

Kujundzic, Elmira; Zander, David A; Hernandez, Mark; Angenent, Largus T; Henderson, David E; Miller, Shelly L

2005-02-01

The purpose of this study was to assess the effectiveness of a new generation of high-volume, ceiling-mounted high-efficiency particulate air (HEPA)-ultraviolet (UV) air filters (HUVAFs) for their ability to remove or inactivate bacterial aerosol. In an environmentally controlled full-scale laboratory chamber (87 m3), and an indoor therapy pool building, the mitigation ability of air filters was assessed by comparing concentrations of total bacteria, culturable bacteria, and airborne endotoxin with and without the air filters operating under otherwise similar conditions. Controlled chamber tests with pure cultures of aerosolized Mycobacterium parafortuitum cells showed that the HUVAF unit tested provided an equivalent air-exchange rate of 11 hr(-1). Using this equivalent air-exchange rate as a design basis, three HUVAFs were installed in an indoor therapy pool building for bioaerosol mitigation, and their effectiveness was studied over a 2-year period. The HUVAFs reduced concentrations of culturable bacteria by 69 and 80% during monitoring periods executed in respective years. The HUVAFs reduced concentrations of total bacteria by 12 and 76% during the same monitoring period, respectively. Airborne endotoxin concentrations were not affected by the HUVAF operation.

40 CFR 721.10279 - Multi-walled carbon nanotubes (generic) (P-10-246).

Code of Federal Regulations, 2014 CFR

2014-07-01

... a loose-fitting hood or helmet and high efficiency particulate air (HEPA) filters; or (C) NIOSH... in § 721.80(f), (k) (conductivity additive to resins, rubber, and to battery electrodes), and (q...

International Space Station (ISS) Bacterial Filter Elements (BFEs): Filter Efficiency and Pressure Testing of Returned Units

NASA Technical Reports Server (NTRS)

Green, Robert D.; Agui, Juan H.; Vijayakumar, R.

2017-01-01

The air revitalization system aboard the International Space Station (ISS) provides the vital function of maintaining a clean cabin environment for the crew and the hardware. This becomes a serious challenge in pressurized space compartments since no outside air ventilation is possible, and a larger particulate load is imposed on the filtration system due to lack of sedimentation due to the microgravity environment in Low Earth Orbit (LEO). The ISS Environmental Control and Life Support (ECLS) system architecture in the U.S. Segment uses a distributed particulate filtration approach consisting of traditional High-Efficiency Particulate Adsorption (HEPA) media filters deployed at multiple locations in each U.S. Segment module; these filters are referred to as Bacterial Filter Elements, or BFEs. These filters see a replacement interval, as part of maintenance, of 2-5 years dependent on location in the ISS. In this work, we present particulate removal efficiency, pressure drop, and leak test results for a sample set of 8 BFEs returned from the ISS after filter replacement. The results can potentially be utilized by the ISS Program to ascertain whether the present replacement interval can be maintained or extended to balance the on-ground filter inventory with extension of the lifetime of ISS beyond 2024. These results can also provide meaningful guidance for particulate filter designs under consideration for future deep space exploration missions.

Advantageous use of HepaRG cells for the screening and mechanistic study of drug-induced steatosis

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

Tolosa, Laia

Only a few in vitro assays have been proposed to evaluate the steatotic potential of new drugs. The present study examines the utility of HepaRG cells as a cell-based assay system for screening drug-induced liver steatosis. A high-content screening assay was run to evaluate multiple toxicity-related cell parameters in HepaRG cells exposed to 28 compounds, including drugs reported to cause steatosis through different mechanisms and non-steatotic compounds. Lipid content was the most sensitive parameter for all the steatotic drugs, whereas no effects on lipid levels were produced by non-steatotic compounds. Apart from fat accumulation, increased ROS production and altered mitochondrialmore » membrane potential were also found in the cells exposed to steatotic drugs, which indicates that all these cellular events contributed to drug-induced hepatotoxicity. These findings are of clinical relevance as most effects were observed at drug concentrations under 100-fold of the therapeutic peak plasmatic concentration. HepaRG cells showed increased lipid overaccumulation vs. HepG2 cells, which suggests greater sensitivity to drug-induced steatosis. An altered expression profile of transcription factors and the genes that code key proteins in lipid metabolism was also found in the cells exposed to drugs capable of inducing liver steatosis. Our results generally indicate the value of HepaRG cells for assessing the risk of liver damage associated with steatogenic compounds and for investigating the molecular mechanisms involved in drug-induced steatosis. - Highlights: • HepaRG cells were explored as an in vitro model to detect steatogenic potential. • Multiple toxicity-related endpoints were analysed by HCS. • HepaRG showed a greater sensitivity to drug-induced steatosis than HepG2 cells. • Changes in the expression of genes related to lipid metabolism were revealed. • HepaRG allow mechanistic understanding of liver damage induced by steatogenic drugs.« less

Factors affecting ozone removal rates in a simulated aircraft cabin environment

NASA Astrophysics Data System (ADS)

Tamás, Gyöngyi; Weschler, Charles J.; Bakó-Biró, Zsolt; Wyon, David P.; Strøm-Tejsen, Peter

Ozone concentrations were measured concurrently inside a simulated aircraft cabin and in the airstream providing ventilation air to the cabin. Ozone decay rates were also measured after cessation of ozone injection into the supply airstream. By systematically varying the presence or absence of people, soiled T-shirts, aircraft seats and a used HEPA filter, we have been able in the course of 24 experiments to isolate the contributions of these and other factors to the removal of ozone from the cabin air. In the case of this simulated aircraft, people were responsible for almost 60% of the ozone removal occurring within the cabin and recirculation system; respiration can only have been responsible for about 4% of this removal. The aircraft seats removed about 25% of the ozone; the loaded HEPA filter, 7%; and the other surfaces, 10%. A T-shirt that had been slept in overnight removed roughly 70% as much ozone as a person, indicating the importance of skin oils in ozone removal. The presence of the used HEPA filter in the recirculated airstream reduced the perceived air quality. Over a 5-h period, the overall ozone removal rate by cabin surfaces decreased at ˜3% h -1. With people present, the measured ratio of ozone's concentration in the cabin versus that outside the cabin was 0.15-0.21, smaller than levels reported in the literature. The results reinforce the conclusion that the optimal way to reduce people's exposure to both ozone and ozone oxidation products is to efficiently remove ozone from the air supply system of an aircraft.

Detection and removal of impurities in nitric oxide generated from air by pulsed electrical discharge.

PubMed

Yu, Binglan; Blaesi, Aron H; Casey, Noel; Raykhtsaum, Grigory; Zazzeron, Luca; Jones, Rosemary; Morrese, Alexander; Dobrynin, Danil; Malhotra, Rajeev; Bloch, Donald B; Goldstein, Lee E; Zapol, Warren M

2016-11-30

Inhalation of nitric oxide (NO) produces selective pulmonary vasodilation without dilating the systemic circulation. However, the current NO/N 2 cylinder delivery system is cumbersome and expensive. We developed a lightweight, portable, and economical device to generate NO from air by pulsed electrical discharge. The objective of this study was to investigate and optimize the purity and safety of NO generated by this device. By using low temperature streamer discharges in the plasma generator, we produced therapeutic levels of NO with very low levels of nitrogen dioxide (NO 2 ) and ozone. Despite the low temperature, spark generation eroded the surface of the electrodes, contaminating the gas stream with metal particles. During prolonged NO generation there was gradual loss of the iridium high-voltage tip (-90 μg/day) and the platinum-nickel ground electrode (-55 μg/day). Metal particles released from the electrodes were trapped by a high-efficiency particulate air (HEPA) filter. Quadrupole mass spectroscopy measurements of effluent gas during plasma NO generation showed that a single HEPA filter removed all of the metal particles. Mice were exposed to breathing 50 parts per million of electrically generated NO in air for 28 days with only a scavenger and no HEPA filter; the mice did not develop pulmonary inflammation or structural changes and iridium and platinum particles were not detected in the lungs of these mice. In conclusion, an electric plasma generator produced therapeutic levels of NO from air; scavenging and filtration effectively eliminated metallic impurities from the effluent gas. Copyright © 2016 Elsevier Inc. All rights reserved.

Detection and Removal of Impurities in Nitric Oxide Generated from Air by Pulsed Electrical Discharge

PubMed Central

Yu, Binglan; Blaesi, Aron H.; Casey, Noel; Raykhtsaum, Grigory; Zazzeron, Luca; Jones, Rosemary; Morrese, Alexander; Dobrynin, Danil; Malhotra, Rajeev; Bloch, Donald B.; Goldstein, Lee E.; Zapol, Warren M.

2016-01-01

Inhalation of nitric oxide (NO) produces selective pulmonary vasodilation without dilating the systemic circulation. However, the current NO/N2 cylinder delivery system is cumbersome and expensive. We developed a lightweight, portable, and economical device to generate NO from air by pulsed electrical discharge. The objective of this study was to investigate and optimize the purity and safety of NO generated by this device. By using low temperature streamer discharges in the plasma generator, we produced therapeutic levels of NO with very low levels of nitrogen dioxide (NO2) and ozone. Despite the low temperature, spark generation eroded the surface of the electrodes, contaminating the gas stream with metal particles. During prolonged NO generation there was gradual loss of the iridium high-voltage tip (−90 µg/day) and the platinum-nickel ground electrode (−55 µg/day). Metal particles released from the electrodes were trapped by a high-efficiency particulate air (HEPA) filter. Quadrupole mass spectroscopy measurements of effluent gas during plasma NO generation showed that a single HEPA filter removed all of the metal particles. Mice were exposed to breathing 50 parts per million of electrically generated NO in air for 28 days with only a scavenger and no HEPA filter; the mice did not develop pulmonary inflammation or structural changes and iridium and platinum particles were not detected in the lungs of these mice. In conclusion, an electric plasma generator produced therapeutic levels of NO from air; scavenging and filtration effectively eliminated metallic impurities from the effluent gas. PMID:27592386

Evaluation of HEPA vacuum cleaning and dry steam cleaning in reducing levels of polycyclic aromatic hydrocarbons and house dust mite allergens in carpets

PubMed Central

Yu, Chang Ho; Yiin, Lih-Ming; Fan, Zhi-Hua (Tina); Rhoads, George G.

2014-01-01

Dry steam cleaning, which has gained recent attention as an effective method to reduce house dust mite (HDM) allergen concentration and loading in carpets, was evaluated in this study for its efficacy in lowering levels of polycyclic aromatic hydrocarbons (PAHs) as well as HDM allergens. Fifty urban homes with wail-to-wall carpets, mostly low-income and with known lead contamination, were studied in 2003 and 2004. Two carpet-cleaning interventions were compared: Repeated HEPA (High Efficiency Particulate Air filtered) vacuuming alone and repeated HEPA vacuuming supplemented with dry steam cleaning. Vacuum samples were collected to measure carpet loading of dust and contaminants immediately before and after cleaning. Paired comparisons were conducted to evaluate the effectiveness of the cleaning protocols in reducing the levels of PAHs and HDM allergens in carpets. The results indicated that both cleaning methods substantially reduced the loading of PAHs and HDM allergens as well as dust in carpets (p < 0.0001). The reductions in loading of dust (64.4%), PAHs (69.1%), and HDM allergens (85.5%), by dry steam cleaning plus repetitive HEPA vacuuming were larger than the reductions by regular HEPA vacuuming alone: dust (55.5%), PAHs (58.6%), and HDM allergens (80.8%), although the difference was statistically significant only for dust and PAHs. We conclude that intensive HEPA vacuum cleaning substantially reduced the loading of PAHs and HDM allergens in carpets in these urban homes and that dry steam cleaning added modestly to cleaning effectiveness. PMID:19137159

Development of an approach to correcting MicroPEM baseline drift.

PubMed

Zhang, Ting; Chillrud, Steven N; Pitiranggon, Masha; Ross, James; Ji, Junfeng; Yan, Beizhan

2018-07-01

Fine particulate matter (PM 2.5 ) is associated with various adverse health outcomes. The MicroPEM (RTI, NC), a miniaturized real-time portable particulate sensor with an integrated filter for collecting particles, has been widely used for personal PM 2.5 exposure assessment. Five-day deployments were targeted on a total of 142 deployments (personal or residential) to obtain real-time PM 2.5 levels from children living in New York City and Baltimore. Among these 142 deployments, 79 applied high-efficiency particulate air (HEPA) filters in the field at the beginning and end of each deployment to adjust the zero level of the nephelometer. However, unacceptable baseline drift was observed in a large fraction (> 40%) of acquisitions in this study even after HEPA correction. This drift issue has been observed in several other studies as well. The purpose of the present study is to develop an algorithm to correct the baseline drift in MicroPEM based on central site ambient data during inactive time periods. A running baseline & gravimetric correction (RBGC) method was developed based on the comparison of MicroPEM readings during inactive periods to ambient PM 2.5 levels provided by fixed monitoring sites and the gravimetric weight of PM 2.5 collected on the MicroPEM filters. The results after RBGC correction were compared with those using HEPA approach and gravimetric correction alone. Seven pairs of duplicate acquisitions were used to validate the RBGC method. The percentages of acquisitions with baseline drift problems were 42%, 53% and 10% for raw, HEPA corrected, and RBGC corrected data, respectively. Pearson correlation analysis of duplicates showed an increase in the coefficient of determination from 0.75 for raw data to 0.97 after RBGC correction. In addition, the slope of the regression line increased from 0.60 for raw data to 1.00 after RBGC correction. The RBGC approach corrected the baseline drift issue associated with MicroPEM data. The algorithm developed has the potential for use with data generated from other types of PM sensors that contain a filter for weighing as well. In addition, this approach can be applied in many other regions, given widely available ambient PM data from monitoring networks, especially in urban areas. Copyright © 2018 Elsevier Inc. All rights reserved.

The use of high-efficiency particulate air-filter respirators to protect hospital workers from tuberculosis. A cost-effectiveness analysis.

PubMed

Adal, K A; Anglim, A M; Palumbo, C L; Titus, M G; Coyner, B J; Farr, B M

1994-07-21

After outbreaks of multidrug-resistant tuberculosis, the Centers for Disease Control and Prevention proposed the use of respirators with high-efficiency particulate air filters (HEPA respirators) as part of isolation precautions against tuberculosis, along with a respiratory-protection program for health care workers that includes medical evaluation, training, and tests of the fit of the respirators. Each HEPA respirator costs between $7.51 and $9.08, about 10 times the cost of respirators currently used. We conducted a cost-effectiveness analysis using data from the University of Virginia Hospital on exposure to patients with tuberculosis and rates at which the purified-protein-derivative (PPD) skin test became positive in hospital workers. The costs of a respiratory-protection program were based on those of an existing program for workers dealing with hazardous substances. During 1992, 11 patients with documented tuberculosis were admitted to our hospital. Eight of 3852 workers (0.2 percent) had PPD tests that became positive. Five of these conversions were believed to be due to the booster phenomenon; one followed unprotected exposure to a patient not yet in isolation; the other two occurred in workers who had never entered a tuberculosis isolation room. These data suggest that it will take more than one year for the use of HEPA respirators to prevent a single conversion of the PPD test. Assuming that one conversion is prevented per year, however, it would take 41 years at out hospital to prevent one case of occupationally acquired tuberculosis, at a cost of $1.3 million to $18.5 million. Given the effectiveness of currently recommended measures to prevent nosocomial transmission of tuberculosis, the addition of HEPA respirators would offer negligible protective efficacy at great cost.

Expression and chromatin structures of cellulolytic enzyme gene regulated by heterochromatin protein 1.

PubMed

Zhang, Xiujun; Qu, Yinbo; Qin, Yuqi

2016-01-01

Heterochromatin protein 1 (HP1, homologue HepA in Penicillium oxalicum ) binding is associated with a highly compact chromatin state accompanied by gene silencing or repression. HP1 loss leads to the derepression of gene expression. We investigated HepA roles in regulating cellulolytic enzyme gene expression, as an increasingly number of studies have suggested that cellulolytic enzyme gene expression is not only regulated by transcription factors, but is also affected by the chromatin status. Among the genes that exhibited significant differences between the hepA deletion strain (Δ hepA ) and the wild type (WT), most (95.0 %) were upregulated in Δ hepA compared with WT. The expression of the key transcription factor for cellulolytic enzyme gene (e.g., repressor CreA and activator ClrB) increased significantly. However, the deletion of hepA led to downregulation of prominent extracellular cellulolytic enzyme genes. Among the top 10 extracellular glycoside hydrolases (Amy15A, Amy13A, Cel7A/CBHI, Cel61A, Chi18A, Cel3A/BGLI, Xyn10A, Cel7B/EGI, Cel5B/EGII, and Cel6A/CBHII), in which secretion amount is from the highest to the tenth in P . oxalicum secretome, eight genes, including two amylase genes ( amy15A and amy13A ), all five cellulase genes ( cel7A / cbh1 , cel6A / cbh2 , cel7B / eg1 , cel5B / eg2 , and cel3A / bgl1 ), and the cellulose-active LPMO gene ( cel61A ) expression were downregulated. Results of chromatin accessibility real-time PCR (CHART-PCR) showed that the chromatin of all three tested upstream regions opened specifically because of the deletion of hepA in the case of two prominent cellulase genes cel7A/cbh1 and cel7B/eg1 . However, the open chromatin status did not occur along with the activation of cellulolytic enzyme gene expression. The overexpression of hepA upregulated the cellulolytic enzyme gene expression without chromatin modification. The overexpression of hepA remarkably activated the cellulolytic enzyme synthesis, not only in WT (~150 % filter paper activity (FPA) increase), but also in the industry strain RE-10 (~20-30 % FPA increase). HepA is required for chromatin condensation of prominent cellulase genes. However, the opening of chromatin mediated by the deletion of hepA was not positively correlated with cellulolytic enzyme gene activation. HepA is actually a positive regulator for cellulolytic enzyme gene expression and could be a promising target for genetic modification to improve cellulolytic enzyme synthesis.

Air filtration systems and restrictive access conditions improve indoor air quality in clinical units: Penicillium as a general indicator of hospital indoor fungal levels.

PubMed

Araujo, Ricardo; Cabral, João Paulo; Rodrigues, Acácio Gonçalves

2008-03-01

High-efficiency particulate air (HEPA) filters do not completely prevent nosocomial fungal infections. The first aim of this study was to evaluate the impact of different filters and access conditions upon airborne fungi in hospital facilities. Additionally, this study identified fungal indicators of indoor air concentrations. Eighteen rooms and wards equipped with different air filter systems, and access conditions were sampled weekly, during 16 weeks. Tap water samples were simultaneously collected. The overall mean concentration of atmospheric fungi for all wards was 100 colony forming units/m(3). We found a direct proportionality between the levels of the different fungi in the studied atmospheres. Wards with HEPA filters at positive air flow yielded lower fungal levels. Also, the existence of an anteroom and the use of protective clothes were associated to the lowest fungal levels. Principal component analysis showed that penicillia afforded the best separation between wards' air fungal levels. Fungal strains were rarely recovered from tap water samples. In addition to air filtration systems, some access conditions to hospital units, like presence of anteroom and use of protective clothes, may prevent high fungal air load. Penicillia can be used as a general indicator of indoor air fungal levels at Hospital S. João.

International Space Station (ISS) Bacterial Filter Elements (BFEs): Filter Efficiency and Pressure Drop Testing of Returned Units

NASA Technical Reports Server (NTRS)

Green, Robert D.; Agui, Juan H.; Vijayakumar, R.; Berger, Gordon M.; Perry, Jay L.

2017-01-01

The air quality control equipment aboard the International Space Station (ISS) and future deep space exploration vehicles provide the vital function of maintaining a clean cabin environment for the crew and the hardware. This becomes a serious challenge in pressurized space compartments since no outside air ventilation is possible, and a larger particulate load is imposed on the filtration system due to lack of sedimentation. The ISS Environmental Control and Life Support (ECLS) system architecture in the U.S. Segment uses a distributed particulate filtration approach consisting of traditional High-Efficiency Particulate Air (HEPA) filters deployed at multiple locations in each U.S. Seg-ment module; these filters are referred to as Bacterial Filter Elements, or BFEs. In our previous work, we presented results of efficiency and pressure drop measurements for a sample set of two returned BFEs with a service life of 2.5 years. In this follow-on work, we present similar efficiency, pressure drop, and leak tests results for a larger sample set of six returned BFEs. The results of this work can aid the ISS Program in managing BFE logistics inventory through the stations planned lifetime as well as provide insight for managing filter element logistics for future exploration missions. These results also can provide meaningful guidance for particulate filter designs under consideration for future deep space exploration missions.

Filter Efficiency and Pressure Testing of Returned ISS Bacterial Filter Elements (BFEs)

NASA Technical Reports Server (NTRS)

Green, Robert D.; Agui, Juan H.; Berger, Gordon M.; Vijayakumar, R.; Perry, Jay L.

2017-01-01

The air quality control equipment aboard the International Space Station (ISS) and future deep space exploration vehicles provide the vital function of maintaining a clean cabin environment for the crew and the hardware. This becomes a serious challenge in pressurized space compartments since no outside air ventilation is possible, and a larger particulate load is imposed on the filtration system due to lack of sedimentation. The ISS Environmental Control and Life Support (ECLS) system architecture in the U.S. Segment uses a distributed particulate filtration approach consisting of traditional High-Efficiency Particulate Air (HEPA) filters deployed at multiple locations in each U.S. Seg-ment module; these filters are referred to as Bacterial Filter Elements, or BFEs. In our previous work, we presented results of efficiency and pressure drop measurements for a sample set of two returned BFEs with a service life of 2.5 years. In this follow-on work, we present similar efficiency, pressure drop, and leak tests results for a larger sample set of six returned BFEs. The results of this work can aid the ISS Program in managing BFE logistics inventory through the stations planned lifetime as well as provide insight for managing filter element logistics for future exploration missions. These results also can provide meaningful guidance for particulate filter designs under consideration for future deep space exploration missions.

Engineering study for a melting, casting, rolling and fabrication facility for recycled contaminated stainless steel

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

NONE

This Preliminary Report is prepared to study the facilities required for recycling contaminated stainless steel scrap into plate which will be fabricated into boxes suitable for the storage of contaminated wastes and rubble. The study is based upon the underlying premise that the most cost effective way to produce stainless steel is to use the same processes employed by companies now in production of high quality stainless steel. Therefore, the method selected for this study for the production of stainless steel plate from scrap is conventional process using an Electric Arc Furnace for meltdown to hot metal, a Continuous Castermore » for production of cast slabs, and a Reversing Hot Mill for rolling the slabs into plate. The fabrication of boxes from the plate utilizes standard Shears, Punch Presses and welding equipment with Robotic Manipulators. This Study presumes that all process fumes, building dusts and vapors will be cycled through a baghouse and a nuclear grade HEPA filter facility prior to discharge. Also, all process waste water will be evaporated into the hot flue gas stream from the furnace utilizing a quench tank; so there will be no liquid discharges from the facility and all vapors will be processed through a HEPA filter. Even though HEPA filters are used today in controlling radioactive contamination from nuclear facilities there is a sparsity of data concerning radioactivity levels and composition of waste that may be collected from contaminated scrap steel processing. This report suggests some solutions to these problems but it is recommended that additional study must be given to these environmental problems.« less

Particulate matter triggers depressive-like response associated with modulation of inflammatory cytokine homeostasis and brain-derived neurotrophic factor signaling pathway in mice.

PubMed

Liu, Xuemei; Qian, Xin; Xing, Jing; Wang, Jinhua; Sun, Yixuan; Wang, Qin'geng; Li, Huiming

2018-04-23

Particulate matter (PM) exposure may contribute to depressive-like response in mice. However, few studies have evaluated the adaptive impacts of long-term PM exposure on depressive-like response associated with systemic inflammation and brain-derived neurotrophic factor (BDNF) signaling pathway. We studied the association among depressive-like behaviors, mRNA levels of pro- and anti-inflammatory cytokines, and the expression of BDNF signaling pathway in mice by long-term PM exposure. C57BL/6 male mice were exposed to ambient air alongside control mice breathing air filtered through a high-efficiency air PM (HEPA) filter. Depressive-like behaviors were assessed together with pro-inflammatory, anti-inflammatory cytokine mRNA levels and the modulation of BDNF pathway in hippocampus and olfactory-bulb of mice exposed to PM for 4, 8, and 12 weeks. Exposure to HEPA filtered air for 4 weeks may exert antidepressant like effects in mice. Pro-inflammatory cytokines were up-regulated while the expression of BDNF, its high-affinity receptor tropomyosin-related kinase B (TrkB), and the transcription factor cAMP-response-element binding protein (CREB) were down-regulated in ambient air mice. However, after 8 weeks, there was no significant difference in the rate of depressive-like behaviors between the two groups. After 12 weeks, mice exposed to ambient air again had a higher rate of depressive-like behaviors, significant up-regulation of pro-inflammatory cytokines, down-regulation of interleukin-10 (IL-10), BDNF, TrkB, and CREB than HEPA mice. Ultrafine PM in brain tissues of mice exposed to ambient air was observed. Our results suggest continuous high-level PM exposure alters the depressive-like response in mice and induces a damage-repair-imbalance reaction.

Pilot-scale tests of HEME and HEPA dissolution process

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

Qureshi, Z.H.; Strege, D.K.

A series of pilot-scale demonstration tests for the dissolution of High Efficiency Mist Eliminators (HEME`s) and High Efficiency Particulate Airfilters (HEPA) were performed on a 1/5th linear scale. These fiberglass filters are to be used in the Defense Waste Processing Facility (DWPF) to decontaminate the effluents from the off-gases generated during the feed preparation process and vitrification. When removed, these filters will be dissolved in the Decontamination Waste Treatment Tank (DWTT) using 5 wt% NaOH solution. The contaminated fiberglass is converted to an aqueous stream which will be transferred to the waste tanks. The filter metal structure will be rinsedmore » with process water before its disposal as low-level solid waste. The pilot-scale study reported here successfully demonstrated a simple one step process using 5 wt% NaOH solution. The proposed process requires the installation of a new water spray ring with 30 nozzles. In addition to the reduced waste generated, the total process time is reduced to 48 hours only (66% saving in time). The pilot-scale tests clearly demonstrated that the dissolution process of HEMEs has two stages - chemical digestion of the filter and mechanical erosion of the digested filter. The digestion is achieved by a boiling 5 wt% caustic solutions, whereas the mechanical break down of the digested filter is successfully achieved by spraying process water on the digested filter. An alternate method of breaking down the digested filter by increased air sparging of the solution was found to be marginally successful are best. The pilot-scale tests also demonstrated that the products of dissolution are easily pumpable by a centrifugal pump.« less

10 CFR 850.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

..., that has end-use functions that depend in whole or in part on its shape or design during end use, and... Element delegates his or her functions under this part. High-efficiency particulate air (HEPA) filter... in this part: Action level means the level of airborne concentration of beryllium established...

10 CFR 850.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

..., that has end-use functions that depend in whole or in part on its shape or design during end use, and... Element delegates his or her functions under this part. High-efficiency particulate air (HEPA) filter... in this part: Action level means the level of airborne concentration of beryllium established...

10 CFR 850.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

..., that has end-use functions that depend in whole or in part on its shape or design during end use, and... Element delegates his or her functions under this part. High-efficiency particulate air (HEPA) filter... in this part: Action level means the level of airborne concentration of beryllium established...

Critically safe vacuum pickup for use in wet or dry cleanup of radioactive materials

DOEpatents

Zeren, Joseph D.

1994-01-01

A vacuum pickup of critically safe quantity and geometric shape is used in cleanup of radioactive materials. Collected radioactive material is accumulated in four vertical, parallel, equally spaced canisters arranged in a cylinder configuration. Each canister contains a filter bag. An upper intake manifold includes four 90 degree spaced, downward facing nipples. Each nipple communicates with the top of a canister. The bottom of each canister communicates with an exhaust manifold comprising four radially extending tubes that meet at the bottom of a centrally located vertical cylinder. The top of the central cylinder terminates at a motor/fan power head. A removable HEPA filter is located intermediate the top of the central cylinder and the power head. Four horizontal bypass tubes connect the top of the central cylinder to the top of each of the canisters. Air enters the vacuum cleaner via a hose connected to the intake manifold. Air then travels down the canisters, where particulate material is accumulated in generally equal quantities in each filter bag. Four air paths of bag filtered air then pass radially inward to the bottom of the central cylinder. Air moves up the central cylinder, through the HEPA filter, through a vacuum fan compartment, and exits the vacuum cleaner. A float air flow valve is mounted at the top of the central cylinder. When liquid accumulates to a given level within the central cylinder, the four bypass tubes, and the four canisters, suction is terminated by operation of the float valve.

METAL MEDIA FILTERS, AG-1 SECTION FI

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

Adamson, D.

One application of metal media filters is in various nuclear air cleaning processes including applications for protecting workers, the public and the environment from hazardous and radioactive particles. To support this application the development of the ASME AG-1 FI Standard on Metal Media has been under way for more than ten years. Development of the proposed section has required resolving several difficult issues associated with operating conditions (media velocity, pressure drop, etc.), qualification testing, and quality acceptance testing. Performance characteristics of metal media are dramatically different than the glass fiber media with respect to parameters like differential pressures, operating temperatures,more » media strength, etc. These differences make existing data for a glass fiber media inadequate for qualifying a metal media filter for AG-1. In the past much work has been conducted on metal media filters at facilities such as Lawrence Livermore National Laboratory (LLNL) and Savannah River National Laboratory (SRNL) to qualify the media as High Efficiency Particulate Air (HEPA) Filters. Particle retention testing has been conducted at Oak Ridge Filter Test Facility and at Air Techniques International (ATI) to prove that the metal media meets or exceeds the 99.97% particle retention required for a HEPA Filter. Even with his testing, data was lacking to complete an AG-1 FI Standard on metal media. With funding secured by Mississippi State University (MSU) from National Nuclear Security Administration (NNSA), a research test stand is being designed and fabricated at MSU's Institute for Clean Energy Technology (ICET) Facility to obtain qualification data on metal media. This in turn will support required data needed for the FI Standard. The paper will discuss in detail how the test stand at MSU will obtain the necessary data to complete the FI Standard.« less

TEST METHODS TO CHARACTERIZE PARTICULATE MATTER EMISSIONS AND DEPOSITION RATES IN A RESEARCH HOUSE

EPA Science Inventory

The paper discusses test methods to characterize particulate matter (PM) emissions and deposition rates in a research house. In a room in the research house, specially configured for PM source testing, a high-efficiency particulate air (HEPA)-filtered air supply system, used for...

Achieving 'excellent' indoor air quality in commercial offices equipped with air-handling unit--respirable suspended particulate.

PubMed

Lam, K S; Chan, F S; Fung, W Y; Lui, B S S; Lau, L W L

2006-04-01

A study was carried out to investigate the feasibility of achieving ultra low respirable suspended particulates (RSP) in commercial offices without major modification of existing ventilation systems by enhancing the particulates removal efficiency of existing central ventilation systems. Four types of filters which include pre-filters, cartridge filters, bag filters and high efficiency particulates air (HEPA) filters were tested in a commercial building in Causeway Bay. The results show that an RSP objective of <20 microg/m3 could be met by removing RSP from both the return air and outdoor air supply simultaneously. This level of performance is classed as 'excellent' by the Hong Kong Government, Environmental Protection Department. Filters with efficiency that exceed 80% placed both in the return air and outdoor air were sufficient to meet the objective. It is not necessary to install HEPA filters to achieve the 'excellent' class. The outdoor air filter has great influence on the steady state indoor RSP concentration while the effective cleaning rate is governed by the return air filter. Higher efficiency filters increased the static drop but the volume flow of the air fan was not affected significantly. The additional cost incurred was <5% of the existing operation cost. This paper reports a field study of RSP control for an indoor office environment. The results are directly applicable to building service engineering in the design of ventilation systems using air-handling units. Field observations indicated that indoor RSP in an office environment could be suppressed below 20 microg/m3 within 1 h by the simultaneous filtration of outdoor air and return air. Outdoor air filtration has a great influence on the steady state indoor concentration and return air filtration governs the cleaning rate. It is believed that the results of this study could be extended to the cleaning of other indoor pollutants such as volatile organic compounds.

Air Cleaning Technologies

PubMed Central

2005-01-01

Executive Summary Objective This health technology policy assessment will answer the following questions: When should in-room air cleaners be used? How effective are in-room air cleaners? Are in-room air cleaners that use combined HEPA and UVGI air cleaning technology more effective than those that use HEPA filtration alone? What is the Plasmacluster ion air purifier in the pandemic influenza preparation plan? The experience of severe acute respiratory syndrome (SARS) locally, nationally, and internationally underscored the importance of administrative, environmental, and personal protective infection control measures in health care facilities. In the aftermath of the SARS crisis, there was a need for a clearer understanding of Ontario’s capacity to manage suspected or confirmed cases of airborne infectious diseases. In so doing, the Walker Commission thought that more attention should be paid to the potential use of new technologies such as in-room air cleaning units. It recommended that the Medical Advisory Secretariat of the Ontario Ministry of Health and Long-Term Care evaluate the appropriate use and effectiveness of such new technologies. Accordingly, the Ontario Health Technology Advisory Committee asked the Medical Advisory Secretariat to review the literature on the effectiveness and utility of in-room air cleaners that use high-efficiency particle air (HEPA) filters and ultraviolet germicidal irradiation (UVGI) air cleaning technology. Additionally, the Ontario Health Technology Advisory Committee prioritized a request from the ministry’s Emergency Management Unit to investigate the possible role of the Plasmacluster ion air purifier manufactured by Sharp Electronics Corporation, in the pandemic influenza preparation plan. Clinical Need Airborne transmission of infectious diseases depends in part on the concentration of breathable infectious pathogens (germs) in room air. Infection control is achieved by a combination of administrative, engineering, and personal protection methods. Engineering methods that are usually carried out by the building’s heating, ventilation, and air conditioning (HVAC) system function to prevent the spread of airborne infectious pathogens by diluting (dilution ventilation) and removing (exhaust ventilation) contaminated air from a room, controlling the direction of airflow and the air flow patterns in a building. However, general wear and tear over time may compromise the HVAC system’s effectiveness to maintain adequate indoor air quality. Likewise, economic issues may curtail the completion of necessary renovations to increase its effectiveness. Therefore, when exposure to airborne infectious pathogens is a risk, the use of an in-room air cleaner to reduce the concentration of airborne pathogens and prevent the spread of airborne infectious diseases has been proposed as an alternative to renovating a HVAC system. Airborne transmission is the spread of infectious pathogens over large distances through the air. Infectious pathogens, which may include fungi, bacteria, and viruses, vary in size and can be dispersed into the air in drops of moisture after coughing or sneezing. Small drops of moisture carrying infectious pathogens are called droplet nuclei. Droplet nuclei are about 1 to 5μm in diameter. This small size in part allows them to remain suspended in the air for several hours and be carried by air currents over considerable distances. Large drops of moisture carrying infectious pathogens are called droplets. Droplets being larger than droplet nuclei, travel shorter distances (about 1 metre) before rapidly falling out of the air to the ground. Because droplet nuclei remain airborne for longer periods than do droplets, they are more amenable to engineering infection control methods than are droplets. Droplet nuclei are responsible for the airborne transmission of infectious diseases such as tuberculosis, chicken pox (varicella), measles (rubeola), and dessiminated herpes zoster, whereas close contact is required for the direct transmission of infectious diseases transmitted by droplets, such as influenza (the flu) and SARS. The Technology In-room air cleaners are supplied as portable or fixed devices. Fixed devices can be attached to either a wall or ceiling and are preferred over portable units because they have a greater degree of reliability (if installed properly) for achieving adequate room air mixing and airflow patterns, which are important for optimal effectiveness. Through a method of air recirculation, an in-room air cleaner can be used to increase room ventilation rates and if used to exhaust air out of the room it can create a negative-pressure room for airborne infection isolation (AII) when the building’s HVAC system cannot do so. A negative-pressure room is one where clean air flows into the room but contaminated air does not flow out of it. Contaminated room air is pulled into the in-room air cleaner and cleaned by passing through a series of filters, which remove the airborne infectious pathogens. The cleaned air is either recirculated into the room or exhausted outside the building. By filtering contaminated room air and then recirculating the cleaned air into the room, an in-room air cleaner can improve the room’s ventilation. By exhausting the filtered air to the outside the unit can create a negative-pressure room. There are many types of in-room air cleaners. They vary widely in the airflow rates through the unit, the type of air cleaning technology used, and the technical design. Crucial to maximizing the efficiency of any in-room air cleaner is its strategic placement and set-up within a room, which should be done in consultation with ventilation engineers, infection control experts, and/or industrial hygienists. A poorly positioned air cleaner may disrupt airflow patterns within the room and through the air cleaner, thereby compromising its air cleaning efficiency. The effectiveness of an in-room air cleaner to remove airborne pathogens from room air depends on several factors, including the airflow rate through the unit’s filter and the airflow patterns in the room. Tested under a variety of conditions, in-room air cleaners, including portable or ceiling mounted units with either a HEPA or a non-HEPA filter, portable units with UVGI lights only, or ceiling mounted units with combined HEPA filtration and UVGI lights, have been estimated to be between 30% and 90%, 99% and 12% and 80% effective, respectively. However, and although their effectiveness is variable, the United States Centers for Disease Control and Prevention has acknowledged in-room air cleaners as alternative technology for increasing room ventilation when this cannot be achieved by the building’s HVAC system with preference given to fixed recirculating systems over portable ones. Importantly, the use of an in-room air cleaner does not preclude either the need for health care workers and visitors to use personal protective equipment (N95 mask or equivalent) when entering AII rooms or health care facilities from meeting current regulatory requirements for airflow rates (ventilation rates) in buildings and airflow differentials for effective negative-pressure rooms. The Plasmacluster ion technology, developed in 2000, is an air purification technology. Its manufacturer, Sharp Electronics Corporation, says that it can disable airborne microorganisms through the generation of both positive and negative ions. (1) The functional unit is the hydroxyl, which is a molecule comprised of one oxygen molecule and one hydrogen atom. Plasmacluster ion air purifier uses a multilayer filter system composed of a prefilter, a carbon filter, an antibacterial filter, and a HEPA filter, combined with an ion generator to purify the air. The ion generator uses an alternating plasma discharge to split water molecules into positively and negatively charged ions. When these ions are emitted into the air, they are surrounded by water molecules and form cluster ions which are attracted to airborne particles. The cluster ion surrounds the airborne particle, and the positive and negative ions react to form hydroxyls. These hydroxyls steal the airborne particle’s hydrogen atom, which creates a hole in the particle’s outer protein membrane, thereby rendering it inactive. Because influenza is primarily acquired by large droplets and direct and indirect contact with an infectious person, any in-room air cleaner will have little benefit in controlling and preventing its spread. Therefore, there is no role for the Plasmacluster ion air purifier or any other in-room air cleaner in the control of the spread of influenza. Accordingly, for purposes of this review, the Medical Advisory Secretariat presents no further analysis of the Plasmacluster. Review Strategy The objective of the systematic review was to determine the effectiveness of in-room air cleaners with built in UVGI lights and HEPA filtration compared with those using HEPA filtration only. The Medical Advisory Secretariat searched the databases of MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, INAHATA (International Network of Agencies for Health Technology Assessment), Biosis Previews, Bacteriology Abstracts, Web of Science, Dissertation Abstracts, and NIOSHTIC 2. A meta-analysis was conducted if adequate data was available from 2 or more studies and where statistical and clinical heterogeneity among studies was not an issue. Otherwise, a qualitative review was completed. The GRADE system was used to summarize the quality of the body of evidence comprised of 1 or more studies. Summary of Findings There were no existing health technology assessments on air cleaning technology located during the literature review. The literature search yielded 59 citations of which none were retained. One study was retrieved from a reference list of a guidance document from the United States Centers for Disease Control and Prevention, which evaluated an in-room air cleaner with combined UVGI lights and HEPA filtration under 2 conditions: UVGI lights on and UVGI lights off. Experiments were performed using different ventilation rates and using an aerosolized pathogen comprised of Mycobaterium parafortuitum, a surrogate for the bacterium that causes tuberculosis. Effectiveness was measured as equivalent air changes per hour (eACH). This single study formed the body of evidence for our systematic review research question. Experimental Results The eACH rate for the HEPA-UVGI in-room air cleaner was statistically significantly greater when the UV lights were on compared with when the UV lights were off. (P < .05). However, subsequent experiments could not attribute this to the UVGI. Consequently, the results are inconclusive and an estimate of effect (benefit) is uncertain. The study was reviewed by a scientific expert and rated moderate for quality. Further analysis determined that there was some uncertainty in the directness of the outcome measure (eACH); thus, the GRADE level for the quality of the evidence was low indicating that an estimate of effect is very uncertain. There is uncertainty in the benefits of using in-room air cleaners with combined UVGI lights and HEPA filtration over systems that use HEPA filtration alone. However, there are no known risks to using systems with combined UVGI and HEPA technology compared with those with HEPA alone. There is an increase in the burden of cost including capital costs (cost of the device), operating costs (electricity usage), and maintenance costs (cleaning and replacement of UVGI lights) to using an in-room air cleaner with combined UVGI and HEPA technology compared with those with HEPA alone. Given the uncertainty of the estimate of benefits, an in-room air cleaner with HEPA technology only may be an equally reasonable alternative to using one with combined UVGI and HEPA technology Conclusions In-room air cleaners may be used to protect health care staff from air borne infectious pathogens such as tuberculosis, chicken pox, measles, and dessiminated herpes zoster. In addition, and although in-room air cleaners are not effective at protecting staff and preventing the spread of droplet-transmitted diseases such as influenza and SARS, they may be deployed in situations with a novel/emerging infectious agent whose epidemiology is not yet defined and where airborne transmission is suspected. It is preferable that in-room air cleaners be used with a fixed and permanent room placement when ventilation requirements must be improved and the HVAC system cannot be used. However, for acute (temporary) situations where a novel/emerging infectious agent presents whose epidemiology is not yet defined and where airborne transmission is suspected it may be prudent to use the in room air cleaner as a portable device until mode of transmission is confirmed. To maximize effectiveness, consultation with an environmental engineer and infection control expert should be undertaken before using an in-room air cleaner and protocols for maintenance and monitoring of these devices should be in place. If properly installed and maintained, in room air cleaners with HEPA or combined HEPA and UVGI air cleaning technology are effective in removing airborne pathogens. However, there is only weak evidence available at this time regarding the benefit of using an in-room air cleaner with combined HEPA and UVGI air cleaner technology instead of those with HEPA filter technology only. PMID:23074468

Interfacial Studies of Whisker and Coated Fiber Reinforced Ceramic Matrix Composites

DTIC Science & Technology

1990-05-31

well as BN coated small diameter (ɘ.7jtm) ARCO whiskers. Tha carbon coated TWS- 400C whiskers were received as-coated from Textron, Inc., Lowell, MA...under negative pressure by means of a Nilfisk filtering system equipped with a Hepa filter. With the health hazards of small whiskers being of utmost...Both of these platelet types were analyzed in the scanning Auger multiprobe (SAM) and found to be very close to stoichiometric SiC with a small amount

Viral Penetration of High Efficiency Particulate Air (HEPA) Filters (PREPRINT)

DTIC Science & Technology

2009-09-01

US Plastics, Lima , 155 Ohio). Each path runs through a test article and thence through one AGI-30 all-glass 156 impinger (Chemglass, Vineland, N.J...rotameter (Blue–White 400, Huntington Beach , California, or PMR1-159 101346, Cole–Parmer, Vernon Hills, Illinois). At the end of the sampling path...fibrous Filters." J. Air Pollution Control Assoc. 30 [4]: 501 377–381. 502 Leenders, G.J.M, A.C. Bolle, and J. Stadhouders. 1984. “A Study of the

U-235 Holdup Measurements in the 321-M Lathe HEPA Banks

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

Salaymeh, S.R.

The Analytical Development Section of Savannah River Technology Center (SRTC) was requested by the Facilities Decommissioning Division (FDD) to determine the holdup of enriched uranium in the 321-M facility as part of an overall deactivation project of the facility. The results of the holdup assays are essential for determining compliance with the Waste Acceptance Criteria, Material Control and Accountability, and to meet criticality safety controls. This report covers holdup measurements of uranium residue in six high efficiency particulate air (HEPA) filter banks of the A-lathe and B-lathe exhaust systems of the 321-M facility. This report discusses the non-destructive assay measurements,more » assumptions, calculations, and results of the uranium holdup in these six items.« less

Evaluation of two cleaning methods for the removal of asbestos fibers from carpet

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

Kominsky, J.R.; Freyberg, R.W.; Chesson, J.

The research study examined the effectiveness of dry vacuuming and wet cleaning for the removal of asbestos fibers from carpet, and evaluated the potential for fiber reentrainment during carpet cleaning activities. Routine carpet cleaning operations using high-efficiency particulate air (HEPA) filtered dry vacuum cleaners and HEPA-filtered hot-water extraction cleaners were simulated on carpet artificially contaminated with asbestos fibers. Overall, wet cleaning the carpet with a hot-water extraction cleaner reduced the level of asbestos contamination by approximately 70 percent. There was no significant evidence of either an increase or a decrease in the asbestos concentration after dry vacuuming. The level ofmore » asbestos contamination had no significant effect on the difference between the carpet asbestos concentrations before and after cleaning. Airborne asbestos concentrations were between two and four times greater during the carpet cleaning activities. The level of asbestos contamination in the carpet cleaning activities. The level of asbestos contamination in the carpet and the type of cleaning method used had no statistically significant effect on the difference between the airborne asbestos concentrations before and during cleaning.« less

In situ fabrication of depth-type hierarchical CNT/quartz fiber filters for high efficiency filtration of sub-micron aerosols and high water repellency

NASA Astrophysics Data System (ADS)

Li, Peng; Zong, Yichen; Zhang, Yingying; Yang, Mengmeng; Zhang, Rufan; Li, Shuiqing; Wei, Fei

2013-03-01

We fabricated depth-type hierarchical CNT/quartz fiber (QF) filters through in situ growth of CNTs upon quartz fiber (QF) filters using a floating catalyst chemical vapor deposition (CVD) method. The filter specific area of the CNT/QF filters is more than 12 times higher than that of the pristine QF filters. As a result, the penetration of sub-micron aerosols for CNT/QF filters is reduced by two orders of magnitude, which reaches the standard of high-efficiency particulate air (HEPA) filters. Simultaneously, due to the fluffy brush-like hierarchical structure of CNTs on QFs, the pore size of the hybrid filters only has a small increment. The pressure drop across the CNT/QF filters only increases about 50% with respect to that of the pristine QF filters, leading to an obvious increased quality factor of the CNT/QF filters. Scanning electron microscope images reveal that CNTs are very efficient in capturing sub-micron aerosols. Moreover, the CNT/QF filters show high water repellency, implying their superiority for applications in humid conditions.We fabricated depth-type hierarchical CNT/quartz fiber (QF) filters through in situ growth of CNTs upon quartz fiber (QF) filters using a floating catalyst chemical vapor deposition (CVD) method. The filter specific area of the CNT/QF filters is more than 12 times higher than that of the pristine QF filters. As a result, the penetration of sub-micron aerosols for CNT/QF filters is reduced by two orders of magnitude, which reaches the standard of high-efficiency particulate air (HEPA) filters. Simultaneously, due to the fluffy brush-like hierarchical structure of CNTs on QFs, the pore size of the hybrid filters only has a small increment. The pressure drop across the CNT/QF filters only increases about 50% with respect to that of the pristine QF filters, leading to an obvious increased quality factor of the CNT/QF filters. Scanning electron microscope images reveal that CNTs are very efficient in capturing sub-micron aerosols. Moreover, the CNT/QF filters show high water repellency, implying their superiority for applications in humid conditions. Electronic supplementary information (ESI) available: Schematic of the synthesis process of the CNT/QF filter; typical size distribution of atomized polydisperse NaCl aerosols used for air filtration testing; images of a QF filter and a CNT/QF filter; SEM image of a CNT/QF filter after 5 minutes of sonication in ethanol; calculation of porosity and filter specific area. See DOI: 10.1039/c3nr34325a

Mold Species in Dust from the International Space Station Identified and Quantified by Mold Specific Quantitative PCR - MCEARD

EPA Science Inventory

Dust was collected over a period of several weeks in 2007 from HEPA filters in the U.S. Laboratory Module of the International Space Station (ISS). The dust was returned on the Space Shuttle Atlantis, mixed, sieved, and the DNA was extracted. Using a DNA-based method called mo...

Mold Species in Dust from the International Space Station Identified and Quantified by Mold Specific Quantitative PCR

EPA Science Inventory

Dust was collected over a period of several weeks in 2007 from HEPA filters in the U.S. Laboratory Module of the International Space Station (ISS). The dust was returned on the Space Shuttle Atlantis, mixed, sieved, and the DNA was extracted. Using a DNA-based method called mol...

40 CFR 721.10572 - Benzamide, N-[[4- [(cyclopropylamino)carbonyl] phenyl]sulfonyl]-2-methoxy-.

Code of Federal Regulations, 2014 CFR

2014-07-01

...-fitting half-face respirator equipped with N100 (if oil aerosols absent), R100, or P100 filters. (B) NIOSH-certified air-purifying, tight-fitting full-face respirator equipped with N100 (if oil aerosols absent...-purifying respirator equipped with a tight-fitting facepiece (either half-face or full-face) and HEPA...

Strategies to Increase After-School Program Staff Skills to Promote Healthy Eating and Physical Activity.

PubMed

Weaver, R Glenn; Beets, Michael W; Beighle, Aaron; Webster, Collin; Huberty, Jennifer; Moore, Justin B

2016-01-01

Standards targeting children's healthy eating and physical activity (HEPA) in after-school programs call for staff to display or refrain from HEPA-promoting or -discouraging behaviors that are linked to children's HEPA. This study evaluated strategies to align staff behaviors with HEPA Standards. Staff at four after-school programs serving approximately 500 children participated in professional development training from January 2012 to May 2013. Site leaders also attended workshops and received technical support during the same time frame. Changes in staff behaviors were evaluated using the System for Observing Staff Promotion of Activity and Nutrition in a pre- (fall 2011) multiple-post (spring 2012, fall 2012, and spring 2013), no-control group study design. A total of 8,949 scans were completed across the four measurement periods. Of the 19 behaviors measured, 14 changed in the appropriate direction. For example, staff engaging in physical activity with children increased from 27% to 40% of scans and staff eating unhealthy foods decreased from 56% to 14% of days. Ongoing training and technical assistance can have a measureable impact on staff behaviors linked to child-level HEPA outcomes. Future research should explore the feasibility of disseminating ongoing trainings to after-school program staff on a large scale. © 2015 Society for Public Health Education.

DEVELOPMENT OF AG-1 SECTION FI ON METAL MEDIA FILTERS - 9061

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

Adamson, D; Charles A. Waggoner, C

Development of a metal media standard (FI) for ASME AG-1 (Code on Nuclear Air and Gas Treatment) has been under way for almost ten years. This paper will provide a brief history of the development process of this section and a detailed overview of its current content/status. There have been at least two points when dramatic changes have been made in the scope of the document due to feedback from the full Committee on Nuclear Air and Gas Treatment (CONAGT). Development of the proposed section has required resolving several difficult issues associated with scope; namely, filtering efficiency, operating conditions (mediamore » velocity, pressure drop, etc.), qualification testing, and quality control/acceptance testing. A proposed version of Section FI is currently undergoing final revisions prior to being submitted for balloting. The section covers metal media filters of filtering efficiencies ranging from medium (less than 99.97%) to high (99.97% and greater). Two different types of high efficiency filters are addressed; those units intended to be a direct replacement of Section FC fibrous glass HEPA filters and those that will be placed into newly designed systems capable of supporting greater static pressures and differential pressures across the filter elements. Direct replacements of FC HEPA filters in existing systems will be required to meet equivalent qualification and testing requirements to those contained in Section FC. A series of qualification and quality assurance test methods have been identified for the range of filtering efficiencies covered by this proposed standard. Performance characteristics of sintered metal powder vs. sintered metal fiber media are dramatically different with respect to parameters like differential pressures and rigidity of the media. Wide latitude will be allowed for owner specification of performance criteria for filtration units that will be placed into newly designed systems. Such allowances will permit use of the most appropriate metal media for a system as specified by the owner with respect to material of manufacture, media velocity, system maximum static pressure, maximum differential pressure across the filter, and similar parameters.« less

Bio-Defense Now: 56 Suggestions for Immediate Improvements

DTIC Science & Technology

2005-05-01

Air Education and Training Command HVAC Heating, Ventilation and Air Conditioning ICAM Improved Chemical Agent Monitor ICD-9-CM Internal...conditioning ( HVAC ) system capabilities, making a big difference in removal of many BW agents. High Efficiency Particulate Air (HEPA) filters are also...agents. This program has developed biological sensor-activated heating, ventilation, and air conditioning ( HVAC ) control sys- tems, high efficiency

Facilities Management Guide for Asbestos and Lead

DTIC Science & Technology

2004-11-01

equipment such as HEPA filtered power tools, portable welding exhaust systems, and paint removal equipment when work disturbs lead. Do not dry sweep ...sampling and analysis of [______] paint bulk and wipe samples by atomic absorption spectrophotometry (AA) or anodic stripping voltametry (ASV...analysis. e. All bulk (destructive) collected for lead shall be analyzed by atomic absorption spectrophotometry (AA) or anodic stripping voltametry

Protection of the vehicle cab environment against bacteria, fungi and endotoxins in composting facilities.

PubMed

Schlosser, O; Huyard, A; Rybacki, D; Do Quang, Z

2012-06-01

Microbial quality of air inside vehicle cabs is a major occupational health risk management issue in composting facilities. Large differences and discrepancies in protection factors between vehicles and between biological agents have been reported. This study aimed at estimating the mean protection efficiency of the vehicle cab environment against bioaerosols with higher precision. In-cab measurement results were also analysed to ascertain whether or not these protection systems reduce workers' exposure to tolerable levels. Five front-end loaders, one mobile mixer and two agricultural tractors pulling windrow turners were investigated. Four vehicles were fitted with a pressurisation and high efficiency particulate air (HEPA) filtration system. The four others were only equipped with pleated paper filter without pressurisation. Bacteria, fungi and endotoxins were measured in 72 pairs of air samples, simultaneously collected inside the cab and on the outside of the cab with a CIP 10-M sampler. A front-end loader, purchased a few weeks previously, fitted with a pressurisation and high efficiency particulate air (HEPA) filtration system, and with a clean cab, exhibited a mean protection efficiency of between 99.47% CI 95% [98.58-99.97%] and 99.91% [99.78-99.98%] depending on the biological agent. It is likely that the lower protection efficiency demonstrated in other vehicles was caused by penetration through the only moderately efficient filters, by the absence of pressurisation, by leakage in the filter-sealing system, and by re-suspension of particles which accumulated in dirty cabs. Mean protection efficiency in regards to bacteria and endotoxins ranged between 92.64% [81.87-97.89%] and 98.61% [97.41-99.38%], and between 92.68% [88.11-96.08%] and 98.43% [97.44-99.22%], respectively. The mean protection efficiency was the lowest when confronted with fungal spores, from 59.76% [4.19-90.75%] to 94.71% [91.07-97.37%]. The probability that in-cab exposure to fungi exceeded the benchmark value for short-term respiratory effects suggests that front-end loaders and mobile mixers in composting facilities should be fitted with a pressurisation and HEPA filtration system, regardless of whether or not the facility is indoors or outdoors. Regarding the tractors, exposure inside the cabs was not significantly reduced. However, in this study, there was a less than 0.01% risk of exceeding the bench mark value associated with fungi related short-term respiratory effects during an 1-h per day windrow turning operation. Pressurisation and a HEPA filtration system can provide safe working conditions inside loaders and mobile mixer with regard to airborne bacteria, fungi and endotoxins in composting facilities. However, regular thorough cleaning of the vehicle cab, as well as overalls and shoes cleaning, and mitigation of leakage in the filter-sealing system are necessary to achieve high levels of protection efficiency. Copyright © 2012 Elsevier Ltd. All rights reserved.

Filter Efficiency and Leak Testing of Returned ISS Bacterial Filter Elements After 2.5 Years of Continuous Operation

NASA Technical Reports Server (NTRS)

Green, Robert D.; Agui, Juan H.; Berger, Gordon M.; Vijayakumar, R.; Perry, Jay L.

2016-01-01

The atmosphere revitalization equipment aboard the International Space Station (ISS) and future deep space exploration vehicles provides the vital functions of maintaining a habitable environment for the crew as well as protecting the hardware from fouling by suspended particulate matter. Providing these functions are challenging in pressurized spacecraft cabins because no outside air ventilation is possible and a larger particulate load is imposed on the filtration system due to lack of sedimentation in reduced gravity conditions. The ISS Environmental Control and Life Support (ECLS) system architecture in the U.S. Segment uses a distributed particulate filtration approach consisting of traditional High-Efficiency Particulate Adsorption (HEPA) filters deployed at multiple locations in each module. These filters are referred to as Bacteria Filter Elements (BFEs). As more experience has been gained with ISS operations, the BFE service life, which was initially one year, has been extended to two to five years, dependent on the location in the U.S. Segment. In previous work we developed a test facility and test protocol for leak testing the ISS BFEs. For this work, we present results of leak testing a sample set of returned BFEs with a service life of 2.5 years, along with particulate removal efficiency and pressure drop measurements. The results can potentially be utilized by the ISS Program to ascertain whether the present replacement interval can be maintained or extended to balance the on-ground filter inventory with extension of the lifetime of ISS to 2024. These results can also provide meaningful guidance for particulate filter designs under consideration for future deep space exploration missions.

Mercury Vacuum Cleaner, Operational Test and Evaluation

DTIC Science & Technology

1981-03-01

Indirect readings were obtained by air sampling with hopcalite tubes and subsequent analysis by the USAF OEHL Analytical Services Division. - r...during the operational and storage modes of the MRS-3 vacuum. During the operational mode, indirect ( hopcalite ) air sampling was periodically taken at...from the top and bottom sides of the HEPA and charcoal filter. During the storage mode, indirect ( hopcalite and dosimeter coil) air sampling was

Home interventions are effective at decreasing indoor nitrogen dioxide concentrations.

PubMed

Paulin, L M; Diette, G B; Scott, M; McCormack, M C; Matsui, E C; Curtin-Brosnan, J; Williams, D L; Kidd-Taylor, A; Shea, M; Breysse, P N; Hansel, N N

2014-08-01

Nitrogen dioxide (NO2 ), a by-product of combustion produced by indoor gas appliances such as cooking stoves, is associated with respiratory symptoms in those with obstructive airways disease. We conducted a three-armed randomized trial to evaluate the efficacy of interventions aimed at reducing indoor NO2 concentrations in homes with unvented gas stoves: (i) replacement of existing gas stove with electric stove; (ii) installation of ventilation hood over existing gas stove; and (iii) placement of air purifiers with high-efficiency particulate air (HEPA) and carbon filters. Home inspection and NO2 monitoring were conducted at 1 week pre-intervention and at 1 week and 3 months post-intervention. Stove replacement resulted in a 51% and 42% decrease in median NO2 concentration at 3 months of follow-up in the kitchen and bedroom, respectively (P = 0.01, P = 0.01); air purifier placement resulted in an immediate decrease in median NO2 concentration in the kitchen (27%, P < 0.01) and bedroom (22%, P = 0.02), but at 3 months, a significant reduction was seen only in the kitchen (20%, P = 0.05). NO2 concentrations in the kitchen and bedroom did not significantly change following ventilation hood installation. Replacing unvented gas stoves with electric stoves or placement of air purifiers with HEPA and carbon filters can decrease indoor NO2 concentrations in urban homes. Several combustion sources unique to the residential indoor environment, including gas stoves, produce nitrogen dioxide (NO2), and higher NO2 concentrations, are associated with worse respiratory morbidity in people with obstructive lung disease. A handful of studies have modified the indoor environment by replacing unvented gas heaters; this study, to our knowledge, is the first randomized study to target unvented gas stoves. The results of this study show that simple home interventions, including replacement of an unvented gas stove with an electric stove or placement of HEPA air purifiers with carbon filters, can significantly decrease indoor NO2 concentrations. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Murine precision-cut lung slices exhibit acute responses following exposure to gasoline direct injection engine emissions.

PubMed

Maikawa, Caitlin L; Zimmerman, Naomi; Rais, Khaled; Shah, Mittal; Hawley, Brie; Pant, Pallavi; Jeong, Cheol-Heon; Delgado-Saborit, Juana Maria; Volckens, John; Evans, Greg; Wallace, James S; Godri Pollitt, Krystal J

2016-10-15

Gasoline direct injection (GDI) engines are increasingly prevalent in the global vehicle fleet. Particulate matter emissions from GDI engines are elevated compared to conventional gasoline engines. The pulmonary effects of these higher particulate emissions are unclear. This study investigated the pulmonary responses induced by GDI engine exhaust using an ex vivo model. The physiochemical properties of GDI engine exhaust were assessed. Precision cut lung slices were prepared using Balb/c mice to evaluate the pulmonary response induced by one-hour exposure to engine-out exhaust from a laboratory GDI engine operated at conditions equivalent to vehicle highway cruise conditions. Lung slices were exposed at an air-liquid interface using an electrostatic aerosol in vitro exposure system. Particulate and gaseous exhaust was fractionated to contrast mRNA production related to polycyclic aromatic hydrocarbon (PAH) metabolism and oxidative stress. Exposure to GDI engine exhaust upregulated genes involved in PAH metabolism, including Cyp1a1 (2.71, SE=0.22), and Cyp1b1 (3.24, SE=0.12) compared to HEPA filtered air (p<0.05). GDI engine exhaust further increased Cyp1b1 expression compared to filtered GDI engine exhaust (i.e., gas fraction only), suggesting this response was associated with the particulate fraction. Exhaust particulate was dominated by high molecular weight PAHs. Hmox1, an oxidative stress marker, exhibited increased expression after exposure to GDI (1.63, SE=0.03) and filtered GDI (1.55, SE=0.04) engine exhaust compared to HEPA filtered air (p<0.05), likely attributable to a combination of the gas and particulate fractions. Exposure to GDI engine exhaust contributes to upregulation of genes related to the metabolism of PAHs and oxidative stress. Copyright © 2016 Elsevier B.V. All rights reserved.

International Space Station Bacteria Filter Element Post-Flight Testing and Service Life Prediction

NASA Technical Reports Server (NTRS)

Perry, J. L.; von Jouanne, R. G.; Turner, E. H.

2003-01-01

The International Space Station uses high efficiency particulate air (HEPA) filters to remove particulate matter from the cabin atmosphere. Known as Bacteria Filter Elements (BFEs), there are 13 elements deployed on board the ISS's U.S. Segment. The pre-flight service life prediction of 1 year for the BFEs is based upon performance engineering analysis of data collected during developmental testing that used a synthetic dust challenge. While this challenge is considered reasonable and conservative from a design perspective, an understanding of the actual filter loading is required to best manage the critical ISS Program resources. Thus testing was conducted on BFEs returned from the ISS to refine the service life prediction. Results from this testing and implications to ISS resource management are discussed. Recommendations for realizing significant savings to the ISS Program are presented.

Contamination Impact of Station Brush Fire on Cleanroom Facilities

NASA Technical Reports Server (NTRS)

Carey, Phil; Blakkolb, Brian

2010-01-01

Brush and forest fires, both naturally occurring and anthropogenic in origin, in proximity to space flight hardware processing facilities raise concerns about the threat of contamination resulting from airborne particulate and molecular components of smoke. Perceptions of the severity of the threat are possibly heightened by the high sensitivity of the human sense of smell to some components present in the smoke of burning vegetation.On August 26th, 2009, a brushfire broke out north of Pasadena, California, two miles from the Jet Propulsion Laboratory. The Station Fire destroyed over 160,000 acres, coming within a few hundred yards of JPL. Smoke concentrations on Lab were very heavy over several days. All Lab operations were halted, and measures were taken to protect personnel, critical hardware, and facilities. Evaluation of real-time cleanroom monitoring data, visualinspection of facilities, filter systems, and analysis of surface cleanliness samples revealed facility environments andhardware were minimally effected.Outside air quality easily exceeded Class Ten Million. Prefilters captured most large ash and soot; multi-stage filtration greatly minimized the impact on the HEPA/ULPA filters. Air quality in HEPA filtered spacecraft assembly cleanrooms remained within Class 10,000 specification throughout. Surface cleanliness was inimally affected, as large particles were effectively removed from the airstream, and sub-micron particles have extremely long settling rates. Approximate particulate fallout within facilities was 0.00011% area coverage/day compared to 0.00038% area coverage/day during normal operations. Deposition of condensable airborne components, as measured in real time, peaked at approximately1.0 ng/cm2/day compared to 0.05 ng/cm2/day nominal.

Contamination impact of station brush fire on cleanroom facilities

NASA Astrophysics Data System (ADS)

Carey, Philip A.; Blakkolb, Brian K.

2010-08-01

Brush and forest fires, both naturally occurring and anthropogenic in origin, in proximity to space flight hardware processing facilities raise concerns about the threat of contamination resulting from airborne particulate and molecular components of smoke. Perceptions of the severity of the threat are possibly heightened by the high sensitivity of the human sense of smell to some components present in the smoke of burning vegetation. On August 26th, 2009, a brushfire broke out north of Pasadena, California, two miles from the Jet Propulsion Laboratory. The Station Fire destroyed over 160,000 acres, coming within a few hundred yards of JPL. Smoke concentrations on Lab were very heavy over several days. All Lab operations were halted, and measures were taken to protect personnel, critical hardware, and facilities. Evaluation of real-time cleanroom monitoring data, visual inspection of facilities, filter systems, and analysis of surface cleanliness samples revealed facility environments and hardware were minimally effected. Outside air quality easily exceeded Class Ten Million. Prefilters captured most large ash and soot; multi-stage filtration greatly minimized the impact on the HEPA/ULPA filters. Air quality in HEPA filtered spacecraft assembly cleanrooms remained within Class 10,000 specification throughout. Surface cleanliness was minimally affected, as large particles were effectively removed from the airstream, and sub-micron particles have extremely long settling rates. Approximate particulate fallout within facilities was 0.00011% area coverage/day compared to 0.00038% area coverage/day during normal operations. Deposition of condensable airborne components, as measured in real time, peaked at approximately 1.0 ng/cm2/day compared to 0.05 ng/cm2/day nominal.

Selecting Cells for Bioartificial Liver Devices and the Importance of a 3D Culture Environment: A Functional Comparison between the HepaRG and C3A Cell Lines.

PubMed

van Wenum, Martien; Adam, Aziza A A; Hakvoort, Theodorus B M; Hendriks, Erik J; Shevchenko, Valery; van Gulik, Thomas M; Chamuleau, Robert A F M; Hoekstra, Ruurdtje

2016-01-01

Recently, the first clinical trials on Bioartificial Livers (BALs) loaded with a proliferative human hepatocyte cell source have started. There are two cell lines that are currently in an advanced state of BAL development; HepaRG and HepG2/C3A. In this study we aimed to compare both cell lines on applicability in BALs and to identify possible strategies for further improvement. We tested both cell lines in monolayer- and BAL cultures on growth characteristics, hepatic differentiation, nitrogen-, carbohydrate-, amino acid- and xenobiotic metabolism. Interestingly, both cell lines adapted the hepatocyte phenotype more closely when cultured in BALs; e.g. monolayer cultures produced lactate, while BAL cultures showed diminished lactate production (C3A) or conversion to elimination (HepaRG), and urea cycle activity increased upon BAL culturing in both cell lines. HepaRG-BALs outperformed C3A-BALs on xenobiotic metabolism, ammonia elimination and lactate elimination, while protein synthesis was comparable. In BAL cultures of both cell lines ammonia elimination correlated positively with glutamine production and glutamate consumption, suggesting ammonia elimination was mainly driven by the balance between glutaminase and glutamine synthetase activity. Both cell lines lacked significant urea cycle activity and both required multiple culture weeks before reaching optimal differentiation in BALs. In conclusion, culturing in BALs enhanced hepatic functionality of both cell lines and from these, the HepaRG cells are the most promising proliferative cell source for BAL application.

Calibration and use of filter test facility orifice plates

NASA Astrophysics Data System (ADS)

Fain, D. E.; Selby, T. W.

1984-07-01

There are three official DOE filter test facilities. These test facilities are used by the DOE, and others, to test nuclear grade HEPA filters to provide Quality Assurance that the filters meet the required specifications. The filters are tested for both filter efficiency and pressure drop. In the test equipment, standard orifice plates are used to set the specified flow rates for the tests. There has existed a need to calibrate the orifice plates from the three facilities with a common calibration source to assure that the facilities have comparable tests. A project has been undertaken to calibrate these orifice plates. In addition to reporting the results of the calibrations of the orifice plates, the means for using the calibration results will be discussed. A comparison of the orifice discharge coefficients for the orifice plates used at the seven facilities will be given. The pros and cons for the use of mass flow or volume flow rates for testing will be discussed. It is recommended that volume flow rates be used as a more practical and comparable means of testing filters. The rationale for this recommendation will be discussed.

Workplace Exposure to Titanium Dioxide Nanopowder Released from a Bag Filter System

PubMed Central

Ji, Jun Ho; Kim, Jong Bum; Lee, Gwangjae; Noh, Jung-Hun; Yook, Se-Jin; Cho, So-Hye; Bae, Gwi-Nam

2015-01-01

Many researchers who use laboratory-scale synthesis systems to manufacture nanomaterials could be easily exposed to airborne nanomaterials during the research and development stage. This study used various real-time aerosol detectors to investigate the presence of nanoaerosols in a laboratory used to manufacture titanium dioxide (TiO2). The TiO2 nanopowders were produced via flame synthesis and collected by a bag filter system for subsequent harvesting. Highly concentrated nanopowders were released from the outlet of the bag filter system into the laboratory. The fractional particle collection efficiency of the bag filter system was only 20% at particle diameter of 100 nm, which is much lower than the performance of a high-efficiency particulate air (HEPA) filter. Furthermore, the laboratory hood system was inadequate to fully exhaust the air discharged from the bag filter system. Unbalanced air flow rates between bag filter and laboratory hood systems could result in high exposure to nanopowder in laboratory settings. Finally, we simulated behavior of nanopowders released in the laboratory using computational fluid dynamics (CFD). PMID:26125024

Particulate matter concentrations in residences: an intervention study evaluating stand-alone filters and air conditioners.

PubMed

Batterman, S; Du, L; Mentz, G; Mukherjee, B; Parker, E; Godwin, C; Chin, J-Y; O'Toole, A; Robins, T; Rowe, Z; Lewis, T

2012-06-01

This study, a randomized controlled trial, evaluated the effectiveness of free-standing air filters and window air conditioners (ACs) in 126 low-income households of children with asthma. Households were randomized into a control group, a group receiving a free-standing HEPA filter placed in the child's sleeping area, and a group receiving the filter and a window-mounted AC. Indoor air quality (IAQ) was monitored for week-long periods over three to four seasons. High concentrations of particulate matter (PM) and carbon dioxide were frequently seen. When IAQ was monitored, filters reduced PM levels in the child's bedroom by an average of 50%. Filter use varied greatly among households and declined over time, for example, during weeks when pollutants were monitored, filter use was initially high, averaging 84±27%, but dropped to 63±33% in subsequent seasons. In months when households were not visited, use averaged only 34±30%. Filter effectiveness did not vary in homes with central or room ACs. The study shows that measurements over multiple seasons are needed to characterize air quality and filter performance. The effectiveness of interventions using free-standing air filters depends on occupant behavior, and strategies to ensure filter use should be an integral part of interventions. Environmental tobacco smoke (ETS) increased particulate matter (PM) levels by about 14 μg/m3 and was often detected using ETS-specific tracers despite restrictions on smoking in the house as reported on questionnaires administered to caregivers. PM concentrations depended on season, filter usage, relative humidity, air exchange ratios, number of children, outdoor PM levels, sweeping/dusting, and presence of a central air conditioner (AC). Free-standing air filters can be an effective intervention that provides substantial reductions in PM concentrations if the filters are used. However, filter use was variable across the study population and declined over the study duration, and thus strategies are needed to encourage and maintain use of filters. The variability in filter use suggests that exposure misclassification is a potential problem in intervention studies using filters. The installation of a room AC in the bedroom, intended to limit air exchange ratios, along with an air filter, did not lower PM levels more than the filter alone. © 2011 John Wiley & Sons A/S.

Whole house particle removal and clean air delivery rates for in-duct and portable ventilation systems.

PubMed

Macintosh, David L; Myatt, Theodore A; Ludwig, Jerry F; Baker, Brian J; Suh, Helen H; Spengler, John D

2008-11-01

A novel method for determining whole house particle removal and clean air delivery rates attributable to central and portable ventilation/air cleaning systems is described. The method is used to characterize total and air-cleaner-specific particle removal rates during operation of four in-duct air cleaners and two portable air-cleaning devices in a fully instrumented test home. Operation of in-duct and portable air cleaners typically increased particle removal rates over the baseline rates determined in the absence of operating a central fan or an indoor air cleaner. Removal rates of 0.3- to 0.5-microm particles ranged from 1.5 hr(-1) during operation of an in-duct, 5-in. pleated media filter to 7.2 hr(-1) for an in-duct electrostatic air cleaner in comparison to a baseline rate of 0 hr(-1) when the air handler was operating without a filter. Removal rates for total particulate matter less than 2.5 microm in aerodynamic diameter (PM2.5) mass concentrations were 0.5 hr(-1) under baseline conditions, 0.5 hr(-1) during operation of three portable ionic air cleaners, 1 hr(-1) for an in-duct 1-in. media filter, 2.4 hr(-1) for a single high-efficiency particle arrestance (HEPA) portable air cleaner, 4.6 hr(-1) for an in-duct 5-in. media filter, 4.7 hr(-1) during operation of five portable HEPA filters, 6.1 hr(-1) for a conventional in-duct electronic air cleaner, and 7.5 hr(-1) for a high efficiency in-duct electrostatic air cleaner. Corresponding whole house clean air delivery rates for PM2.5 attributable to the air cleaner independent of losses within the central ventilation system ranged from 2 m3/min for the conventional media filter to 32 m3/min for the high efficiency in-duct electrostatic device. Except for the portable ionic air cleaner, the devices considered here increased particle removal indoors over baseline deposition rates.

Overexpression of HepaCAM inhibits cell viability and motility through suppressing nucleus translocation of androgen receptor and ERK signaling in prostate cancer.

PubMed

Song, Xuedong; Wang, Yin; Du, Hongfei; Fan, Yanru; Yang, Xue; Wang, Xiaorong; Wu, Xiaohou; Luo, Chunli

2014-07-01

HepaCAM is suppressed in a variety of human cancers, and involved in cell adhesion, growth, migration, invasion, and survival. However, the expression and function of HepaCAM in prostate cancer are still unknown. HepaCAM expression has been detected by RT-PCR, Western blotting and immunohistochemistry staining in prostate cell lines RWPE-1, LNCap, DU145, PC3, and in 75 human prostate tissue specimens, respectively. Meanwhile, the cell proliferation ability was detected by WST-8 assay. The role of HepaCAM in prostate cancer cell migration and invasion was examined by wound healing and transwell assay. And flow cytometry was used to observe the apoptosis of prostate cancer cells. Then we detected changes of Androgen Receptor translocation and ERK signaling using immunofluorescence staining and western blot after overexpression of HepaCAM. The HepaCAM expression was significantly down-regulated in prostate cancer tissues and undetected in prostate cancer cells. However, the low HepaCAM expression was not statistically associated with clinicopathological characteristics of prostate cancer. Overexpression of HepaCAM in prostate cancer cells decreased the cell proliferation, migration and invasion, and induced the cell apoptosis. Meanwhile, HepaCAM prevented the androgen receptor translocation from the cytoplasm to the nucleus and down-regulated the MAPK/ERK signaling. Our results suggested that HepaCAM acted as a tumor suppressor in prostate cancer. HepaCAM inhibited cell viability and motility which might be through suppressing the nuclear translocation of Androgen Receptor and down-regulating the ERK signaling. Therefore, it was indicated that HepaCAM may be a potential therapeutic target for prostate cancer. © 2014 Wiley Periodicals, Inc.

Home interventions are effective at decreasing indoor nitrogen dioxide concentrations

PubMed Central

Paulin, L. M.; Diette, G. B.; Scott, M.; McCormack, M. C.; Matsui, E. C.; Curtin-Brosnan, J.; Williams, D. L.; Kidd-Taylor, A.; Shea, M.; Breysse, P. N.; Hansel, N. N.

2016-01-01

Nitrogen dioxide (NO2), a by-product of combustion produced by indoor gas appliances such as cooking stoves, is associated with respiratory symptoms in those with obstructive airways disease. We conducted a three-armed randomized trial to evaluate the efficacy of interventions aimed at reducing indoor NO2 concentrations in homes with unvented gas stoves: (i) replacement of existing gas stove with electric stove; (ii) installation of ventilation hood over existing gas stove; and (iii) placement of air purifiers with high-efficiency particulate air (HEPA) and carbon filters. Home inspection and NO2 monitoring were conducted at 1 week pre-intervention and at 1 week and 3 months post-intervention. Stove replacement resulted in a 51% and 42% decrease in median NO2 concentration at 3 months of follow-up in the kitchen and bedroom, respectively (P = 0.01, P = 0.01); air purifier placement resulted in an immediate decrease in median NO2 concentration in the kitchen (27%, P < 0.01) and bedroom (22%, P = 0.02), but at 3 months, a significant reduction was seen only in the kitchen (20%, P = 0.05). NO2 concentrations in the kitchen and bedroom did not significantly change following ventilation hood installation. Replacing unvented gas stoves with electric stoves or placement of air purifiers with HEPA and carbon filters can decrease indoor NO2 concentrations in urban homes. PMID:24329966

Method for contamination control and barrier apparatus with filter for containing waste materials that include dangerous particulate matter

DOEpatents

Pinson, Paul A.

1998-01-01

A container for hazardous waste materials that includes air or other gas carrying dangerous particulate matter has incorporated in barrier material, preferably in the form of a flexible sheet, one or more filters for the dangerous particulate matter sealably attached to such barrier material. The filter is preferably a HEPA type filter and is preferably chemically bonded to the barrier materials. The filter or filters are preferably flexibly bonded to the barrier material marginally and peripherally of the filter or marginally and peripherally of air or other gas outlet openings in the barrier material, which may be a plastic bag. The filter may be provided with a backing panel of barrier material having an opening or openings for the passage of air or other gas into the filter or filters. Such backing panel is bonded marginally and peripherally thereof to the barrier material or to both it and the filter or filters. A coupling or couplings for deflating and inflating the container may be incorporated. Confining a hazardous waste material in such a container, rapidly deflating the container and disposing of the container, constitutes one aspect of the method of the invention. The chemical bonding procedure for producing the container constitutes another aspect of the method of the invention.

Method for contamination control and barrier apparatus with filter for containing waste materials that include dangerous particulate matter

DOEpatents

Pinson, P.A.

1998-02-24

A container for hazardous waste materials that includes air or other gas carrying dangerous particulate matter has incorporated barrier material, preferably in the form of a flexible sheet, and one or more filters for the dangerous particulate matter sealably attached to such barrier material. The filter is preferably a HEPA type filter and is preferably chemically bonded to the barrier materials. The filter or filters are preferably flexibly bonded to the barrier material marginally and peripherally of the filter or marginally and peripherally of air or other gas outlet openings in the barrier material, which may be a plastic bag. The filter may be provided with a backing panel of barrier material having an opening or openings for the passage of air or other gas into the filter or filters. Such backing panel is bonded marginally and peripherally thereof to the barrier material or to both it and the filter or filters. A coupling or couplings for deflating and inflating the container may be incorporated. Confining a hazardous waste material in such a container, rapidly deflating the container and disposing of the container, constitutes one aspect of the method of the invention. The chemical bonding procedure for producing the container constitutes another aspect of the method of the invention. 3 figs.

Hepa1-6-FLuc cell line with the stable expression of firefly luciferase retains its primary properties with promising bioluminescence imaging ability.

PubMed

Li, Yasha; Liu, Mengnan; Cui, Jiejie; Yang, Ke; Zhao, Li; Gong, Mengjia; Wang, Yi; He, Yun; He, Tongchuan; Bi, Yang

2018-05-01

Reliable animal models are required for the in vivo study of the molecular mechanisms and effects of chemotherapeutic drugs in hepatocarcinoma. In vivo tracing techniques based on firefly luciferase (FLuc) may optimize the non-invasive monitoring of experimental animals. The present study established a murine Hepa1-6-FLuc cell line that stably expressed a retrovirus-delivered FLuc protein gene. The cell morphology, proliferation, migration and invasion ability of Hepa1-6-FLuc cells were the same as that of the Hepa1-6 cells, and thus is suitable to replace Hepa1-6 cells in the construction of hepatocarcinoma animal models. No differences in subcutaneous tumor mass and its pathomorphology from implanted Hepa1-6-FLuc cells were observed compared with Hepa1-6 control tumors. Bioluminescence imaging indicated that the Luc signal of the Hepa1-6-FLuc cells was consistently strengthened with increases in tumor mass; however, the Luc signal of Hepa1-6-AdFLuc became weaker and eventually disappeared during tumor development. Therefore, compared with the transient expression by adenovirus, stable expression of the FLuc gene in Hepa1-6 cells may better reflect cell proliferation and survival in vivo , and provide a reliable source for the establishment of hepatocarcinoma models.

The Air Pollution Exposure Laboratory (APEL) for controlled human exposure to diesel exhaust and other inhalants: characterization and comparison to existing facilities.

PubMed

Birger, Nicholas; Gould, Timothy; Stewart, James; Miller, Mark R; Larson, Timothy; Carlsten, Chris

2011-03-01

The Air Pollution Exposure Laboratory (APEL) was designed for the controlled inhalation of human subjects to aged and diluted diesel exhaust (DE) to mimic "real-world" occupational and environmental conditions. An EPA Tier 3-compliant, 6.0 kW diesel generator is operated under discrete cyclic loads to simulate diesel on-road emissions. The engine accepts standard ultra-low sulfur diesel or a variety of alternative fuels (such as biodiesel) via a partitioned tank. A portion of raw exhaust is drawn into the primary dilution system and is diluted 9:1 with compressed air at standard temperature (20°C) and humidity (40%) levels. The exhaust is further diluted approximately 25:1 by high efficiency particulate air (HEPA)-filtered air (FA) and then aged for 4 min before entering the 4 × 6 × 7-foot exposure booth. An optional HEPA filter path immediately proximal to the booth can generate a particle-reduced (gas-enriched) exposure. In-booth particulate is read by a nephelometer to provide an instantaneous light scattering coefficient for closed-loop system control. A Scanning Mobility Particle Sizer and multi-stage impactor measures particle size distribution. Filter sampling allows determination of sessional average concentrations of size-fractionated and unfractionated particulate oxidative potential, elemental carbon, organic carbon and trace elements. Approximately 300 μg/m(3) PM(2.5) is routinely achievable at APEL and is well characterized in terms of oxidative potential and elemental components. APEL efficiently creates fresh DE, appropriately aged and diluted for human experimentation at safe yet realistic concentrations. Description of exposure characteristics allows comparison to other international efforts to deepen the current evidence base regarding the health effects of DE.

ANALYSIS OF VAPORS FROM METHYLENE CHLORIDE EXTRACTS OF NUCLEAR GRADE HEPA FILTER FIBERGLASS SAMPLES

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

FRYE JM; ANASTOS HL; GUTIERREZ FC

2012-06-07

While several organic compounds were detected in the vapor samples used in the reenactment of the preparation of mounts from the extracts of nuclear grade high-efficiency particulate air filter fiberglass samples, the most significant species present in the samples were methylene chloride, phenol, phenol-d6, and 2-fluorophenol. These species were all known to be present in the extracts, but were expected to have evaporated during the preparation of the mounts, as the mounts appeared to be dry before any vapor was collected. These species were present at the following percentages of their respective occupational exposure limits: methylene chloride, 2%; phenol, 0.4%;more » and phenol-d6, 0.6%. However, there is no established limit for 2-fluorophenol. Several other compounds were detected at low levels for which, as in the case of 2-fluorophenol, there are no established permissible exposure limits. These compounds include 2-chlorophenol; N-nitroso-1-propanamine; 2-fluoro-1,1{prime}-biphenyl; 1,2-dihydroacenaphthylene; 2,5-cyclohexadiene-1,4-dione,2,6-bis(1,1-dimethylethyl); trimethyl oxirane; n-propylpropanamine; 2-(Propylamino)ethanol; 4-methoxy-1-butene; 6-methyl-5-hepten-2-one; and 3,4-dimethylpyridine. Some of these were among those added as surrogates or spike standards as part ofthe Advanced Technologies and Laboratories International, Inc. preparation ofthe extract of the HEPA filter media and are indicated as such in the data tables in Section 2, Results; other compounds found were not previously known to be present. The main inorganic species detected (sulfate, sodium, and sulfur) are also consistent with species added in the preparation of the methylene chloride extract of the high-efficiency particulate air sample.« less

Promotion of health-enhancing physical activity in rheumatoid arthritis: a comparative study on healthcare providers in Italy, The Netherlands and Sweden.

PubMed

Brodin, Nina; Hurkmans, Emalie; DiMatteo, Luigi; Nava, Tiziana; Vliet Vlieland, Thea; Opava, Christina H

2015-10-01

The objectives of this study were to compare attitudes, practice of advice, perceived competencies and educational needs related to health-enhancing physical activity (HEPA) in rheumatoid arthritis (RA) among Dutch, Italian and Swedish healthcare providers (HCP) and to explore associations between these factors and age, gender and HEPA levels of HCP. Questionnaires were sent to 2939 HCP, members of their national rheumatology organizations. HEPA was assessed with the Short Questionnaire to Assess Health-Enhancing Physical Activity or the International Physical Activity Questionnaire; attitudes, practice of advice, perceived competencies and educational needs with a 23-item questionnaire. Overall response rate was 33 %. Ninety-five percent of HCP agreed that HEPA is an important health goal in RA. More Swedish HCP had positive attitudes to the attainability and safety of HEPA in RA. There were no differences between countries in practice of advice on HEPA to patients with RA in general or to those with recent onset disease, but more Italian HCP were reluctant to advise HEPA to patients with established disease. Of the total HCP, 36 to 60 % used public health guidelines to advise on HEPA, with Dutch HCP taking less advantage. Still they estimated a higher proportion of patients with RA to follow such advice. Italian HCP perceived their competencies the highest, but were also more interested in education to promote HEPA. Gender, age and HEPA performance had no association with attitudes toward HEPA, while a number of associations were found between these factors and practice of advice and perceived competencies. The differences found between HCP in the three countries might indicate the need for educational initiatives to improve HEPA promotion.

Contextualizing Hepatocyte Functionality of Cryopreserved HepaRG Cell Cultures

PubMed Central

Jackson, Jonathan P.; Li, Linhou; Chamberlain, Erica D.; Wang, Hongbing

2016-01-01

Over the last decade HepaRG cells have emerged as a promising alternative to primary human hepatocytes (PHH) and have been featured in over 300 research publications. Most of these reports employed freshly differentiated HepaRG cells that require time-consuming culture (∼28 days) for full differentiation. Recently, a cryopreserved, predifferentiated format of HepaRG cells (termed here “cryo-HepaRG”) has emerged as a new model that improves global availability and experimental flexibility; however, it is largely unknown whether HepaRG cells in this format fully retain their hepatic characteristics. Therefore, we systematically investigated the hepatocyte functionality of cryo-HepaRG cultures in context with the range of interindividual variation observed with PHH in both sandwich-culture and suspension formats. These evaluations uncovered a novel adaptation period for the cryo-HepaRG format and demonstrated the impact of extracellular matrix on cryo-HepaRG functionality. Pharmacologically important drug-metabolizing alleles were genotyped in HepaRG cells and poor metabolizer alleles for CYP2D6, CYP2C9, and CYP3A5 were identified and consistent with higher frequency alleles found in individuals of Caucasian decent. We observed liver enzyme inducibility with aryl hydrocarbon receptor, constitutive androstane receptor (CAR), and pregnane X receptor activators comparable to that of sandwich-cultured PHH. Finally, we show for the first time that cryo-HepaRG supports proper CAR cytosolic sequestration and translocation to hepatocyte nuclei in response to phenobarbital treatment. Taken together, these data reveal important considerations for the use of this cell model and demonstrate that cryo-HepaRG are suitable for metabolism and toxicology screening. PMID:27338863

Tank 241-Z-361 Sludge Retrieval and Treatment Alternatives

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

HAMPTON, B.K.

2000-05-24

The Plutonium Finishing Plant (PFP) Tank 241-Z-361 (Z-361) contains legacy sludge resulting from waste discharges from past missions at PFP. A sketch of the tank is shown in Figure 1. In this view various risers and penetrations are shown along with the sludge level depicted by the horizontal line halfway up the tank, and the ground level depicted by the horizontal line above the tank. The HEPA filter installed for breathing is also shown on one of the risers.

7. VIEW LOOKING WEST DOWN CENTRAL AVENUE AT THE INTERSECTION ...

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

7. VIEW LOOKING WEST DOWN CENTRAL AVENUE AT THE INTERSECTION WITH SEVENTH STREET. THE PLANT WAS BUILT ON THE SITE WITH FOUR SEPARATE PRODUCTION AREAS, AND AN ADMINISTRATION AND SUPPORT AREA. THIS PHOTOGRAPH SHOWS THE EASTERN EDGE OF THE CORE ADMINSTRATION AND SUPPORT AREA, BUILT IN THE EARLY 1950S. IN THE LEFT FOREGROUND OF THE PHOTOGRAPH IS BUILDING 442, USED TO TEST ALL HEPA FILTERS ON SITE. - Rocky Flats Plant, Bounded by Indiana Street & Routes 93, 128 & 72, Golden, Jefferson County, CO

235U Holdup Measurements in Three 321-M Exhaust HEPA Banks

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

Dewberry, R

2005-02-24

The Analytical Development Section of Savannah River National Laboratory (SRNL) was requested by the Facilities Disposition Division to determine the holdup of enriched uranium in the 321-M facility as part of an overall deactivation project of the facility. The 321-M facility was used to fabricate enriched uranium fuel assemblies, lithium-aluminum target tubes, neptunium assemblies, and miscellaneous components for the production reactors. The results of the holdup assays are essential for determining compliance with the Waste Acceptance Criteria, Material Control & Accountability, and to meet criticality safety controls. This report covers holdup measurements of uranium residue in three HEPA filter exhaustmore » banks of the 321-M facility. Each of the exhaust banks has dimensions near 7' x 14' x 4' and represents a complex holdup problem. A portable HPGe detector and EG&G Dart system that contains the high voltage power supply and signal processing electronics were used to determine highly enriched uranium (HEU) holdup. A personal computer with Gamma-Vision software was used to control the Dart MCA and to provide space to store and manipulate multiple 4096-channel {gamma}-ray spectra. Some acquisitions were performed with the portable detector configured to a Canberra Inspector using NDA2000 acquisition and analysis software. Our results for each component uses a mixture of redundant point source and area source acquisitions that yielded HEU contents in the range of 2-10 grams. This report discusses the methodology, non-destructive assay (NDA) measurements, assumptions, and results of the uranium holdup in these items. This report includes use of transmission-corrected assay as well as correction for contributions from secondary area sources.« less

Simple Freeze-Drying Procedure for Producing Nanocellulose Aerogel-Containing, High-Performance Air Filters.

PubMed

Nemoto, Junji; Saito, Tsuguyuki; Isogai, Akira

2015-09-09

Simple freeze-drying of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibril (TOCN) dispersions in water/tert-butyl alcohol (TBA) mixtures was conducted to prepare TOCN aerogels as high-performance air filter components. The dispersibility of the TOCNs in the water/TBA mixtures, and the specific surface area (SSA) of the resulting TOCN aerogels, was investigated as a function of the TBA concentration in the mixtures. The TOCNs were homogeneously dispersed in the water/TBA mixtures at TBA concentrations up to 40% w/w. The SSAs of the TOCN aerogels exceeded 300 m2/g when the TBA concentration in the aqueous mixtures was in the range from 20% to 50% w/w. When a commercially available, high-efficiency particulate air (HEPA) filter was combined with TOCN/water/TBA dispersions prepared using 30% TBA, and the product was freeze-dried, the resulting TOCN aerogel-containing filters showed superior filtration properties. This was because nanoscale, spider-web-like networks of the TOCNs with large SSAs were formed within the filter.

Isolation, Purification, and Characterization of Five Active Diketopiperazine Derivatives from Endophytic Streptomyces SUK 25 with Antimicrobial and Cytotoxic Activities.

PubMed

Alshaibani, Muhanna; Zin, Noraziah; Jalil, Juriyati; Sidik, Nik; Ahmad, Siti Junaidah; Kamal, Nurkhalida; Edrada-Ebel, Ruangelie

2017-07-28

In our search for new sources of bioactive secondary metabolites from Streptomyces sp., the ethyl acetate extracts from endophytic Streptomyces SUK 25 afforded five active diketopiperazine (DKP) compounds. The aim of this study was to characterize the bioactive compounds isolated from endophytic Streptomyces SUK 25 and evaluate their bioactivity against multiple drug resistance (MDR) bacteria such as Enterococcus raffinosus, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter spp., and their cytotoxic activities against the human hepatoma (HepaRG) cell line. The production of secondary metabolites by this strain was optimized through Thornton's medium. Isolation, purification, and identification of the bioactive compounds were carried out using high-performance liquid chromatography, high-resolution mass liquid chromatography-mass spectrometry, Fourier transform infrared spectroscopy, and nuclear magnetic resonance, and cryopreserved HepaRG cells were selected to test the cytotoxicity. The results showed that endophytic Streptomyces SUK 25 produces four active DKP compounds and an acetamide derivative, which were elucidated as cyclo -( L -Val- L -Pro), cyclo -( L -Leu- L -Pro), cyclo -( L -Phe- L -Pro), cyclo -( L -Val- L -Phe), and N -(7-hydroxy-6-methyl-octyl)-acetamide. These active compounds exhibited activity against methicillin-resistant S. aureus ATCC 43300 and Enterococcus raffinosus , with low toxicity against human hepatoma HepaRG cells. Endophytic Streptomyces SUK 25 has the ability to produce DKP derivatives biologically active against some MDR bacteria with relatively low toxicity against HepaRG cells line.

A pilot study to investigate the effects of combined dehumidification and HEPA filtration on dew point and airborne mold spore counts in day care centers.

PubMed

Bernstein, J A; Levin, L; Crandall, M S; Perez, A; Lanphear, B

2005-12-01

Meteorological factors such as relative humidity directly correlate with airborne fungal levels outdoors and indoors. While dehumidification alone is effective at reducing moisture necessary for mold growth, it is inadequate as a single intervention as it does not remove viable and non-viable fungal spores that are potentially allergenic. The purpose of this pilot study was to investigate whether dehumidification in combination with high-efficiency particulate arrestance (HEPA) filtration is effective at reducing airborne mold spore levels in day care centers. Two day care centers within a 2-mile radius of each other were selected. Day care center A was 2 years old with eight rooms while day care center B was 15 years old with six rooms. A high efficiency Santa Fe dehumidification unit equipped with a HEPA filter was installed in half the rooms (intervention) of each day care facility. Electronic HOBO data loggers continuously measured outdoor and indoor room dew point and temperature every 2 h throughout the study. Dew point and airborne fungal spore measurements from selected rooms with controlled air conditions were analyzed by comparing baseline measurements to those obtained at subsequent time periods over 1 year. Regression models accounted for correlations between measurements in the same room over time. Intervention resulted in a lowered average dew point from baseline by 8.8 degrees C compared with a decrease of 7.1 degrees C in non-intervention rooms across all time periods in both facilities (P<0.001). Fungal analyses demonstrated lower baseline (P=0.06) and follow-up means in intervention rooms (P<0.05), however the change from baseline to end of follow-up differed between intervention and non-intervention rooms in the two facilities. Log transformation was applied to approximate normality of fungal measurements. Dehumidification with HEPA filtration was effective at controlling indoor dew point in both facilities and at reducing airborne culturable fungal spore levels in one of the two facilities. These preliminary results provide a scientific rationale for using this intervention in future studies designed to investigate the impact of indoor mold exposure on health outcomes. Poor indoor air quality is a recognized cause or contributing factor to health effects. Dampness and humidity have been linked to upper and lower respiratory symptoms in children and adults. This study indicates that reducing indoor relative humidity and airborne mold spore levels using high-efficiency dehumidification units equipped with HEPA filtration is feasible even in work facilities such as day care centers where traffic in and out of the building is difficult to regulate. Clinicians should emphasize to their patients the importance of dehumidification and HEPA filtration to improve indoor air quality in the home and workplace.

Summary of Martian Dust Filtering Challenges and Current Filter Development

NASA Technical Reports Server (NTRS)

O'Hara, William J., IV

2017-01-01

Traditional air particulate filtering in manned spaceflight (Apollo, Shuttle, ISS, etc.) has used cleanable or replaceable catch filters such as screens and High-Efficiency Particulate Arrestance (HEPA) filters. However, the human mission to Mars architecture will require a new approach. It is Martian dust that is the particulate of concern but the need also applies to particulates generated by crew. The Mars Exploration Program Analysis Group (MEPAG) high-lighted this concern in its Mars Science, Goals, Objectives, Investigations and Priorities document [7], by saying specifically that one high priority investigation will be to "Test ISRU atmospheric processing systems to measure resilience with respect to dust and other environmental challenge performance parameters that are critical to the design of a full-scale system." By stating this as high priority the MEPAG is acknowledging that developing and adequately verifying this capability is critical to success of a human mission to Mars. This architecture will require filtering capabilities that are highly reliable, will not restrict the flow path with clogging, and require little to no maintenance. This paper will summarize why this is the case, the general requirements for developing the technology, and the status of the progress made in this area.

Physician Knowledge and Attitudes About Hepatitis A and Current Practices Regarding Hepatitis A Vaccination Delivery.

PubMed

Nelson, Noele P; Allison, Mandy A; Lindley, Megan C; Brtnikova, Michaela; Crane, Lori A; Beaty, Brenda L; Hurley, Laura P; Kempe, Allison

2017-07-01

To assess physicians': 1) knowledge and attitudes about hepatitis A disease and hepatitis A (HepA) vaccine, 2) child care and school HepA vaccine mandates, 3) practices related to HepA vaccine delivery, 4) factors associated with strongly recommending HepA vaccine to all 1- to 2-year-olds, and 5) feasibility of implementing HepA catch-up vaccination at health maintenance visits. A national survey was conducted among representative networks of pediatricians and family medicine physicians (FMs) from March to June, 2014 via e-mail or mail on the basis of provider preference. Response rates were 81% (356 of 440) among pediatricians and 75% (348 of 464) among FMs. Less than 50% correctly identified that hepatitis A virus (HAV) infection is usually asymptomatic in young children and that morbidity from HAV disease increases with age. Ninety-two percent of pediatricians and 59% of FMs strongly recommend HepA vaccine for all 1- to 2-year-olds. In addition to practice specialty, belief that HepA vaccine is required for kindergarten enrollment was the most robust predictor of strong physician recommendation. Gaps in knowledge regarding HAV infection and hepatitis A recommendations and lack of a strong recommendation for routine HepA vaccination of young children among FMs likely contribute to suboptimal coverage. Closing knowledge gaps and addressing barriers that prevent all physicians from strongly recommending HepA vaccine to 1- to 2-year-olds could help increase HepA vaccine coverage and ultimately improve population protection against HAV infection. Published by Elsevier Inc.

Current and maintained health-enhancing physical activity in rheumatoid arthritis: a cross-sectional study.

PubMed

Demmelmaier, Ingrid; Bergman, Patrick; Nordgren, Birgitta; Jensen, Irene; Opava, Christina H

2013-07-01

To describe and identify the explanatory factors of variation in current and maintained health-enhancing physical activity (HEPA) in persons with rheumatoid arthritis (RA). In this cross-sectional study, current HEPA was assessed with the International Physical Activity Questionnaire and maintained HEPA with the Exercise Stage Assessment Instrument, the latter explicitly focusing on both aerobic physical activity and muscle strength training. Sociodemographic, disease-related, and psychosocial data were retrieved from the Swedish Rheumatology Quality (SRQ) registers and a postal questionnaire. The explained variations in the respective HEPA behaviors were analyzed with logistic regression. In all, 3,152 (58.5%) of 5,391 persons identified as eligible from the SRQ registers responded to the questionnaire. Current HEPA was reported by 69%, and maintained HEPA by 11% of the respondents. The most salient and consistent factors explaining variation in both current and maintained HEPA were self-efficacy, social support, and outcome expectations related to physical activity. To our knowledge, this is the first study exploring maintained physical activity in a large well-defined sample of persons with RA. Our results indicate that a minority perform maintained HEPA, including both aerobic physical activity and muscle strength training, and that psychosocial factors are the most salient and consistent in the explanation of HEPA variation. Copyright © 2013 by the American College of Rheumatology.

Photodynamic efficiency of a chlorophyll-a derivative in vitro and in vivo.

PubMed

Zhang, Xiang-Hua; Zhang, Li-Jun; Sun, Jing-Jian; Yan, Yi-Jia; Zhang, Li-Xin; Chen, Na; Chen, Zhi-Long

2016-07-01

This paper reports the antitumor activity of a chlorophyll-a derivative, 2-[1-hydroxyethyl]-2-devinylpyropheophorbide-a (HEPa). Photophysical characteristics of HEPa were measured. And its cytotoxicity, intracellular localization, biodistribution, efficiency of photodynamic therapy (PDT), histological analysis were investigated using human bile duct carcinoma cells (QBC-939) and QBC-939 tumor bearing BABL/c nude mice as animal model. The results showed that HEPa was localized mainly within the cytoplasmic region and partially in lysosome. Biodistribution of HEPa in QBC-939 tumor bearing BABL/c nude mice showed its fast rate of clearance and high tumor selectivity. In vitro, HEPa had low dark toxicity and high photoxicity against QBC-939 cells. The inhibition rate of QBC-939 tumor could increase up to 92.3%, and H&E staining confirmed that HEPa could cause serious damage to the tumor with light dose of 100J/cm(2), implying that HEPa has potential to be a new antitumor candidate for photodynamic therapy (PDT). Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Ceramic High Efficiency Particulate Air (HEPA) Filter Final Report CRADA No. TC02102.0

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

Mitchell, M.; Morse, T.

This was a collaborative effort between Lawrence Livermore National Security, LLC (formerly The Regents of the University of California)/Lawrence Livermor e National Laboratory (LLNL) and Flanders-Precisionaire (Flanders), to develop ceramic HEP A filters under a Thrust II Initiative for Proliferation Prevention (IPP) project. The research was conducted via the IPP Program at Commonwe alth of Independent States (CIS) Institutes, which are handled under a separate agreement. The institutes (collectively referred to as "CIS Institutes") involved with this project were: Bochvar: Federal State Unitarian Enterprise All-Russia Scientific and Research Institute of Inorganic Materials (FSUE VNIINM); Radium Khlopin: Federal State Unitarian Enterprisemore » NPO Radium Institute named (FSUE NPO Radium Institute); and Bakor: Science and Technology Center Bakor (STC Bakor).« less

Viral Penetration of High Efficiency Particulate Air (HEPA) Filters

DTIC Science & Technology

2007-02-01

ml. For aerosol studies the MS2 coli phage was either diluted in sterile distilled water or 0.5% tryptone to a concentration ~108 PFU/mL. Collison...increased to 38%; an increase of 30.5% over MS2 suspended in water . The mass curve is not complete, and thus the fraction of particles in the 100–300 nm...a decrease of 14% over what is observed for MS2 suspended in water . The overall number of particles generated by MS2 + 0.5% tryptone and MS2 in

Air cleaning technologies: an evidence-based analysis.

PubMed

2005-01-01

This health technology policy assessment will answer the following questions: When should in-room air cleaners be used?How effective are in-room air cleaners?Are in-room air cleaners that use combined HEPA and UVGI air cleaning technology more effective than those that use HEPA filtration alone?What is the Plasmacluster ion air purifier in the pandemic influenza preparation plan?The experience of severe acute respiratory syndrome (SARS) locally, nationally, and internationally underscored the importance of administrative, environmental, and personal protective infection control measures in health care facilities. In the aftermath of the SARS crisis, there was a need for a clearer understanding of Ontario's capacity to manage suspected or confirmed cases of airborne infectious diseases. In so doing, the Walker Commission thought that more attention should be paid to the potential use of new technologies such as in-room air cleaning units. It recommended that the Medical Advisory Secretariat of the Ontario Ministry of Health and Long-Term Care evaluate the appropriate use and effectiveness of such new technologies. Accordingly, the Ontario Health Technology Advisory Committee asked the Medical Advisory Secretariat to review the literature on the effectiveness and utility of in-room air cleaners that use high-efficiency particle air (HEPA) filters and ultraviolet germicidal irradiation (UVGI) air cleaning technology. Additionally, the Ontario Health Technology Advisory Committee prioritized a request from the ministry's Emergency Management Unit to investigate the possible role of the Plasmacluster ion air purifier manufactured by Sharp Electronics Corporation, in the pandemic influenza preparation plan. Airborne transmission of infectious diseases depends in part on the concentration of breathable infectious pathogens (germs) in room air. Infection control is achieved by a combination of administrative, engineering, and personal protection methods. Engineering methods that are usually carried out by the building's heating, ventilation, and air conditioning (HVAC) system function to prevent the spread of airborne infectious pathogens by diluting (dilution ventilation) and removing (exhaust ventilation) contaminated air from a room, controlling the direction of airflow and the air flow patterns in a building. However, general wear and tear over time may compromise the HVAC system's effectiveness to maintain adequate indoor air quality. Likewise, economic issues may curtail the completion of necessary renovations to increase its effectiveness. Therefore, when exposure to airborne infectious pathogens is a risk, the use of an in-room air cleaner to reduce the concentration of airborne pathogens and prevent the spread of airborne infectious diseases has been proposed as an alternative to renovating a HVAC system. Airborne transmission is the spread of infectious pathogens over large distances through the air. Infectious pathogens, which may include fungi, bacteria, and viruses, vary in size and can be dispersed into the air in drops of moisture after coughing or sneezing. Small drops of moisture carrying infectious pathogens are called droplet nuclei. Droplet nuclei are about 1 to 5μm in diameter. This small size in part allows them to remain suspended in the air for several hours and be carried by air currents over considerable distances. Large drops of moisture carrying infectious pathogens are called droplets. Droplets being larger than droplet nuclei, travel shorter distances (about 1 metre) before rapidly falling out of the air to the ground. Because droplet nuclei remain airborne for longer periods than do droplets, they are more amenable to engineering infection control methods than are droplets. Droplet nuclei are responsible for the airborne transmission of infectious diseases such as tuberculosis, chicken pox (varicella), measles (rubeola), and dessiminated herpes zoster, whereas close contact is required for the direct transmission of infectious diseases transmitted by droplets, such as influenza (the flu) and SARS. In-room air cleaners are supplied as portable or fixed devices. Fixed devices can be attached to either a wall or ceiling and are preferred over portable units because they have a greater degree of reliability (if installed properly) for achieving adequate room air mixing and airflow patterns, which are important for optimal effectiveness. Through a method of air recirculation, an in-room air cleaner can be used to increase room ventilation rates and if used to exhaust air out of the room it can create a negative-pressure room for airborne infection isolation (AII) when the building's HVAC system cannot do so. A negative-pressure room is one where clean air flows into the room but contaminated air does not flow out of it. Contaminated room air is pulled into the in-room air cleaner and cleaned by passing through a series of filters, which remove the airborne infectious pathogens. The cleaned air is either recirculated into the room or exhausted outside the building. By filtering contaminated room air and then recirculating the cleaned air into the room, an in-room air cleaner can improve the room's ventilation. By exhausting the filtered air to the outside the unit can create a negative-pressure room. There are many types of in-room air cleaners. They vary widely in the airflow rates through the unit, the type of air cleaning technology used, and the technical design. Crucial to maximizing the efficiency of any in-room air cleaner is its strategic placement and set-up within a room, which should be done in consultation with ventilation engineers, infection control experts, and/or industrial hygienists. A poorly positioned air cleaner may disrupt airflow patterns within the room and through the air cleaner, thereby compromising its air cleaning efficiency. The effectiveness of an in-room air cleaner to remove airborne pathogens from room air depends on several factors, including the airflow rate through the unit's filter and the airflow patterns in the room. Tested under a variety of conditions, in-room air cleaners, including portable or ceiling mounted units with either a HEPA or a non-HEPA filter, portable units with UVGI lights only, or ceiling mounted units with combined HEPA filtration and UVGI lights, have been estimated to be between 30% and 90%, 99% and 12% and 80% effective, respectively. However, and although their effectiveness is variable, the United States Centers for Disease Control and Prevention has acknowledged in-room air cleaners as alternative technology for increasing room ventilation when this cannot be achieved by the building's HVAC system with preference given to fixed recirculating systems over portable ones. Importantly, the use of an in-room air cleaner does not preclude either the need for health care workers and visitors to use personal protective equipment (N95 mask or equivalent) when entering AII rooms or health care facilities from meeting current regulatory requirements for airflow rates (ventilation rates) in buildings and airflow differentials for effective negative-pressure rooms. The Plasmacluster ion technology, developed in 2000, is an air purification technology. Its manufacturer, Sharp Electronics Corporation, says that it can disable airborne microorganisms through the generation of both positive and negative ions. (1) The functional unit is the hydroxyl, which is a molecule comprised of one oxygen molecule and one hydrogen atom. Plasmacluster ion air purifier uses a multilayer filter system composed of a prefilter, a carbon filter, an antibacterial filter, and a HEPA filter, combined with an ion generator to purify the air. The ion generator uses an alternating plasma discharge to split water molecules into positively and negatively charged ions. When these ions are emitted into the air, they are surrounded by water molecules and form cluster ions which are attracted to airborne particles. The cluster ion surrounds the airborne particle, and the positive and negative ions react to form hydroxyls. These hydroxyls steal the airborne particle's hydrogen atom, which creates a hole in the particle's outer protein membrane, thereby rendering it inactive. Because influenza is primarily acquired by large droplets and direct and indirect contact with an infectious person, any in-room air cleaner will have little benefit in controlling and preventing its spread. Therefore, there is no role for the Plasmacluster ion air purifier or any other in-room air cleaner in the control of the spread of influenza. Accordingly, for purposes of this review, the Medical Advisory Secretariat presents no further analysis of the Plasmacluster. The objective of the systematic review was to determine the effectiveness of in-room air cleaners with built in UVGI lights and HEPA filtration compared with those using HEPA filtration only. The Medical Advisory Secretariat searched the databases of MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, INAHATA (International Network of Agencies for Health Technology Assessment), Biosis Previews, Bacteriology Abstracts, Web of Science, Dissertation Abstracts, and NIOSHTIC 2. A meta-analysis was conducted if adequate data was available from 2 or more studies and where statistical and clinical heterogeneity among studies was not an issue. Otherwise, a qualitative review was completed. The GRADE system was used to summarize the quality of the body of evidence comprised of 1 or more studies. There were no existing health technology assessments on air cleaning technology located during the literature review. The literature search yielded 59 citations of which none were retained. (ABSTRACT TRUNCATED)

Xenobiotic metabolism in the fish hepatic cell lines Hepa-E1 and RTH-149, and the gill cell lines RTgill-W1 and G1B: Biomarkers of CYP450 activity and oxidative stress.

PubMed

Franco, Marco E; Sutherland, Grace E; Lavado, Ramon

2018-04-01

The use of fish cell cultures has proven to be an effective tool in the study of environmental and aquatic toxicology. Valuable information can be obtained from comparisons between cell lines from different species and organs. In the present study, specific chemicals were used and biomarkers (e.g. 7-Ethoxyresorufin-O-deethylase (EROD) activity and reactive oxygen species (ROS)) were measured to assess the metabolic capabilities and cytotoxicity of the fish hepatic cell lines Hepa-E1 and RTH-149, and the fish gill cell lines RTgill-W1 and G1B. These cell lines were exposed to β-naphthoflavone (BNF) and benzo[a]pyrene (BaP), the pharmaceutical tamoxifen (TMX), and the organic peroxide tert-butylhydroperoxide (tBHP). Cytotoxicity in gill cell lines was significantly higher than in hepatic cells, with BNF and TMX being the most toxic compounds. CYP1-like associated activity, measured through EROD activity, was only detected in hepatic cells; Hepa-E1 cells showed the highest activity after exposure to both BNF and BaP. Significantly higher levels of CYP3A-like activity were also observed in Hepa-E1 cells exposed to TMX, while gill cell lines presented the lowest levels. Measurements of ROS and antioxidant enzymes indicated that peroxide levels were higher in gill cell lines in general. However, levels of superoxide were significantly higher in RTH-149 cells, where no distinctive increase of superoxide-related antioxidants was observed. The present study demonstrates the importance of selecting adequate cell lines in measuring specific metabolic parameters and provides strong evidence for the fish hepatocarcinoma Hepa-E1 cells to be an excellent alternative in assessing metabolism of xenobiotics, and in expanding the applicability of fish cell lines for in vitro studies. Copyright © 2018 Elsevier Inc. All rights reserved.

Hepatic tissue environment in NEMO-deficient mice critically regulates positive selection of donor cells after hepatocyte transplantation.

PubMed

Kaldenbach, Michaela; Cubero, Francisco Javier; Erschfeld, Stephanie; Liedtke, Christian; Trautwein, Christian; Streetz, Konrad

2014-01-01

Hepatocyte transplantation (HT) is a promising alternative treatment strategy for end-stage liver diseases compared with orthotopic liver transplantation. A limitation for this approach is the low engraftment of donor cells. The deletion of the I-kappa B kinase-regulatory subunit IKKγ/NEMO in hepatocytes prevents nuclear factor (NF)-kB activation and triggers spontaneous liver apoptosis, chronic hepatitis and the development of liver fibrosis and hepatocellular carcinoma. We hypothesized that NEMOΔhepa mice may therefore serve as an experimental model to study HT. Pre-conditioned NEMOΔhepa mice were transplanted with donor-hepatocytes from wildtype (WT) and mice deficient for the pro-apoptotic mediator Caspase-8 (Casp8Δhepa). Transplantation of isolated WT-hepatocytes into pre-conditioned NEMOΔhepa mice resulted in a 6-7 fold increase of donor cells 12 weeks after HT, while WT-recipients showed no liver repopulation. The use of apoptosis-resistant Casp8Δhepa-derived donor cells further enhanced the selection 3-fold after 12-weeks and up to 10-fold increase after 52 weeks compared with WT donors. While analysis of NEMOΔhepa mice revealed strong liver injury, HT-recipient NEMOΔhepa mice showed improved liver morphology and decrease in serum transaminases. Concomitant with these findings, the histological examination elicited an improved liver tissue architecture associated with significantly lower levels of apoptosis, decreased proliferation and a lesser amount of liver fibrogenesis. Altogether, our data clearly support the therapeutic benefit of the HT procedure into NEMOΔhepa mice. This study demonstrates the feasibility of the NEMOΔhepa mouse as an in vivo tool to study liver repopulation after HT. The improvement of the characteristic phenotype of chronic liver injury in NEMOΔhepa mice after HT suggests the therapeutic potential of HT in liver diseases with a chronic inflammatory phenotype and opens a new door for the applicability of this technique to combat liver disease in the human clinic.

Hepatic Tissue Environment in NEMO-Deficient Mice Critically Regulates Positive Selection of Donor Cells after Hepatocyte Transplantation

PubMed Central

Kaldenbach, Michaela; Cubero, Francisco Javier; Erschfeld, Stephanie; Liedtke, Christian; Trautwein, Christian; Streetz, Konrad

2014-01-01

Background Hepatocyte transplantation (HT) is a promising alternative treatment strategy for end-stage liver diseases compared with orthotopic liver transplantation. A limitation for this approach is the low engraftment of donor cells. The deletion of the I-kappa B kinase-regulatory subunit IKKγ/NEMO in hepatocytes prevents nuclear factor (NF)-kB activation and triggers spontaneous liver apoptosis, chronic hepatitis and the development of liver fibrosis and hepatocellular carcinoma. We hypothesized that NEMOΔhepa mice may therefore serve as an experimental model to study HT. Methods Pre-conditioned NEMOΔhepa mice were transplanted with donor-hepatocytes from wildtype (WT) and mice deficient for the pro-apoptotic mediator Caspase-8 (Casp8Δhepa). Results Transplantation of isolated WT-hepatocytes into pre-conditioned NEMOΔhepa mice resulted in a 6-7 fold increase of donor cells 12 weeks after HT, while WT-recipients showed no liver repopulation. The use of apoptosis-resistant Casp8Δhepa-derived donor cells further enhanced the selection 3-fold after 12-weeks and up to 10-fold increase after 52 weeks compared with WT donors. While analysis of NEMOΔhepa mice revealed strong liver injury, HT-recipient NEMOΔhepa mice showed improved liver morphology and decrease in serum transaminases. Concomitant with these findings, the histological examination elicited an improved liver tissue architecture associated with significantly lower levels of apoptosis, decreased proliferation and a lesser amount of liver fibrogenesis. Altogether, our data clearly support the therapeutic benefit of the HT procedure into NEMOΔhepa mice. Conclusion This study demonstrates the feasibility of the NEMOΔhepa mouse as an in vivo tool to study liver repopulation after HT. The improvement of the characteristic phenotype of chronic liver injury in NEMOΔhepa mice after HT suggests the therapeutic potential of HT in liver diseases with a chronic inflammatory phenotype and opens a new door for the applicability of this technique to combat liver disease in the human clinic. PMID:24979756

Evaluation of environmental filtration control of engineered nanoparticles using the Harvard Versatile Engineered Nanomaterial Generation System (VENGES)

NASA Astrophysics Data System (ADS)

Tsai, Candace S.-J.; Echevarría-Vega, Manuel E.; Sotiriou, Georgios A.; Santeufemio, Christopher; Schmidt, Daniel; Demokritou, Philip; Ellenbecker, Michael

2012-05-01

Applying engineering controls to airborne engineered nanoparticles (ENPs) is critical to prevent environmental releases and worker exposure. This study evaluated the effectiveness of two air sampling and six air cleaning fabric filters at collecting ENPs using industrially relevant flame-made engineered nanoparticles generated using a versatile engineered nanomaterial generation system (VENGES), recently designed and constructed at Harvard University. VENGES has the ability to generate metal and metal oxide exposure atmospheres while controlling important particle properties such as primary particle size, aerosol size distribution, and agglomeration state. For this study, amorphous SiO2 ENPs with a 15.4 nm primary particle size were generated and diluted with HEPA-filtered air. The aerosol was passed through the filter samples at two different filtration face velocities (2.3 and 3.5 m/min). Particle concentrations as a function of particle size were measured upstream and downstream of the filters using a specially designed filter test system to evaluate filtration efficiency. Real time instruments (FMPS and APS) were used to measure particle concentration for diameters from 5 to 20,000 nm. Membrane-coated fabric filters were found to have enhanced nanoparticle collection efficiency by 20-46 % points compared to non-coated fabric and could provide collection efficiency above 95 %.

Evaluation of environmental filtration control of engineered nanoparticles using the Harvard Versatile Engineered Nanomaterial Generation System (VENGES)

PubMed Central

Echevarría-Vega, Manuel E.; Sotiriou, Georgios A.; Santeufemio, Christopher; Schmidt, Daniel; Demokritou, Philip; Ellenbecker, Michael

2013-01-01

Applying engineering controls to airborne engineered nanoparticles (ENPs) is critical to prevent environmental releases and worker exposure. This study evaluated the effectiveness of two air sampling and six air cleaning fabric filters at collecting ENPs using industrially relevant flame-made engineered nanoparticles generated using a versatile engineered nanomaterial generation system (VENGES), recently designed and constructed at Harvard University. VENGES has the ability to generate metal and metal oxide exposure atmospheres while controlling important particle properties such as primary particle size, aerosol size distribution, and agglomeration state. For this study, amorphous SiO2 ENPs with a 15.4 nm primary particle size were generated and diluted with HEPA-filtered air. The aerosol was passed through the filter samples at two different filtration face velocities (2.3 and 3.5 m/min). Particle concentrations as a function of particle size were measured upstream and downstream of the filters using a specially designed filter test system to evaluate filtration efficiency. Real time instruments (FMPS and APS) were used to measure particle concentration for diameters from 5 to 20,000 nm. Membrane-coated fabric filters were found to have enhanced nanoparticle collection efficiency by 20–46 % points compared to non-coated fabric and could provide collection efficiency above 95 %. PMID:23412707

Women's Health-Enhancing Physical Activity and Eudaimonic Well Being

ERIC Educational Resources Information Center

Ferguson, Leah J.; Kowalski, Kent C.; Mack, Diane E.; Wilson, Philip M.; Crocker, Peter R. E.

2012-01-01

In this study, we explored the role of health-enhancing physical activity (HEPA; Miilunpalo, 2001) in women's eudaimonic well being (i.e., psychological flourishing at one's maximal potential; Ryff, 1989). We used a quantitative approach (N = 349) to explore the relationship between HEPA and eudaimonic well being. While HEPA was not related to…

Altered Hepa1-6 cells by dimethyl sulfoxide (DMSO)-treatment induce anti-tumor immunity in vivo.

PubMed

Jiang, Zhengyu; Zhang, Hongxia; Wang, Ye; Yu, Bin; Wang, Chen; Liu, Changcheng; Lu, Juan; Chen, Fei; Wang, Minjun; Yu, Xinlu; Lin, Jiahao; Pan, Xinghua; Wang, Pin; Zhu, Haiying

2016-02-23

Cancer immunotherapy is the use of the immune system to treat cancer. Our current research proposed an optional strategy of activating immune system involving in cancer immunotherapy. When being treated with 2% DMSO in culture medium, Hepa1-6 cells showed depressed proliferation with no significant apoptosis or decreased viability. D-hep cells, Hepa1-6 cells treated with DMSO for 7 days, could restore to the higher proliferation rate in DMSO-free medium, but alteration of gene expression profile was irreversible. Interestingly, tumors from D-hep cells, not Hepa1-6 cells, regressed in wild-type C57BL/6 mice whereas D-hep cells exhibited similar tumorigenesis as Hep1-6 cells in immunodeficient mice. As expected, additional Hepa1-6 cells failed to form tumors in the D-hep-C57 mice in which D-hep cells were eliminated. Further research confirmed that D-hep-C57 mice established anti-tumor immunity against Hepa1-6 cells. Our research proposed viable tumor cells with altered biological features by DMSO-treatment could induce anti-tumor immunity in vivo.

Hepatocyte specific deletion of c-Met leads to the development of severe non-alcoholic steatohepatitis in mice.

PubMed

Kroy, Daniela C; Schumacher, Fabienne; Ramadori, Pierluigi; Hatting, Maximilian; Bergheim, Ina; Gassler, Nikolaus; Boekschoten, Mark V; Müller, Michael; Streetz, Konrad L; Trautwein, Christian

2014-10-01

Non-alcoholic-fatty-liver disease (NAFLD) is part of the metabolic syndrome. The spectrum of NAFLD includes NASH (non-alcoholic steatohepatitis), which is characterised by progressive inflammation associated with oxidative stress and apoptosis, finally triggering liver cirrhosis and hepatocellular carcinoma. HGF (hepatocyte growth factor)/mesenchymal-epithelial transition factor (c-Met) receptor signalling is known to activate distinct intracellular pathways mediating among others anti-apoptotic properties to hepatocytes. Therefore, the aim was to characterise the role of c-Met during NASH development. Hepatocyte specific c-Met knockout mice (c-MetΔ(hepa)) using the cre-loxP system and wild type controls (c-Met(loxP/loxP)) were fed a methionine-choline deficient (MCD) diet. MCD feeding triggered massive steatosis, decreased survival and higher transaminases in c-MetΔ(hepa) livers compared to c-Met(loxP/loxP). Gene array analysis demonstrated that genes involved in fatty acid metabolism were strongly upregulated in c-MetΔ(hepa) livers correlating with higher amounts of hepatic free fatty acids. Consequently, c-MetΔ(hepa) mice showed significantly more TUNEL positive cells and more superoxide anion production than c-Met(loxPloxP) animals. Additionally, c-MetΔ(hepa) livers showed significantly larger fractions of infiltrating neutrophils, macrophages, and cytotoxic T cells. These changes correlated with an enhanced progression of liver fibrosis as evidenced by higher collagen deposition in c-MetΔ(hepa) livers. As increased apoptosis was a prominent feature in c-MetΔ(hepa) livers, we generated c-Met/Casp8Δ(hepa) double knockout mice. In these animals compared to c-MetΔ(hepa) animals the increase in apoptosis could be reverted. c-Met deletion in hepatocytes triggers NASH progression. A prominent mechanism is higher fatty acid accumulation and increased apoptosis, which in part can be reverted by blocking caspase 8. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

The Start2Bike program is effective in increasing health-enhancing physical activity: a controlled study.

PubMed

Ooms, Linda; Veenhof, Cindy; de Bakker, Dinny H

2017-06-29

The sports club is seen as a new relevant setting to promote health-enhancing physical activity (HEPA) among inactive population groups. Little is known about the effectiveness of strategies and activities implemented in the sports club setting on increasing HEPA levels. This study investigated the effects of Start2Bike, a six-week training program for inactive adults and adult novice cyclers, on HEPA levels of participants in the Netherlands. To measure physical activity, the Short QUestionnaire to ASsess Health-enhancing physical activity was used (SQUASH). Start2Bike participants were measured at baseline, six weeks and six months. A matched control group was measured at baseline and six months. The main outcome measure was whether participants met the Dutch Norm for Health-enhancing Physical Activity (DNHPA: 30 min of moderate-intensity activity on five days a week); Fit-norm (20 min of vigorous-intensity activity on three days a week); and Combi-norm (meeting the DNHPA and/or Fit-norm). Other outcome measures included: total minutes of physical activity per week; and minutes of physical activity per week per domain and intensity category. Statistical analyses consisted of McNemar tests and paired t-tests (within-group changes); and multiple logistic and linear regression analyses (between-group changes). In the Start2Bike group, compliance with Dutch physical activity norms increased significantly, both after six weeks and six months. Control group members did not alter their physical activity behavior. Between-group analyses showed that participants in the Start2Bike group were more likely to meet the Fit-norm at the six-month measurement compared to the control group (odds ratio = 2.5; 95% confidence interval (CI) = 1.1-5.8, p = 0.03). This was due to the Start2Bike participants spending on average 193 min/week more in vigorous-intensity activities (b = 193; 95% CI = 94-293, p < 0.001) and 130 min/week more in sports activities (b = 130; 95% CI = 82-178, p < 0.001) than control group members. Start2Bike positively influences HEPA levels of participants by increasing participation in sport. A relatively short sporting program, offered by a sports club, can be used to encourage less active people to engage in and continue sport at HEPA levels. Overall, sport can contribute to health through increased HEPA and the sports club can serve as a setting to stimulate this.

Organophosphates in aircraft cabin and cockpit air--method development and measurements of contaminants.

PubMed

Solbu, Kasper; Daae, Hanne Line; Olsen, Raymond; Thorud, Syvert; Ellingsen, Dag Gunnar; Lindgren, Torsten; Bakke, Berit; Lundanes, Elsa; Molander, Paal

2011-05-01

Methods for measurements and the potential for occupational exposure to organophosphates (OPs) originating from turbine and hydraulic oils among flying personnel in the aviation industry are described. Different sampling methods were applied, including active within-day methods for OPs and VOCs, newly developed passive long-term sample methods (deposition of OPs to wipe surface areas and to activated charcoal cloths), and measurements of OPs in high-efficiency particulate air (HEPA) recirculation filters (n = 6). In total, 95 and 72 within-day OP and VOC samples, respectively, have been collected during 47 flights in six different models of turbine jet engine, propeller and helicopter aircrafts (n = 40). In general, the OP air levels from the within-day samples were low. The most relevant OP in this regard originating from turbine and engine oils, tricresyl phosphate (TCP), was detected in only 4% of the samples (min-max

Method for dissolution and stabilization of silica-rich fibers

DOEpatents

Jantzen, Carol M.

1997-01-01

A method for dissolving silica-rich fibers such as borosilicate fibers, fiberglass and asbestos to stabilize them for disposal. The method comprises (1) immersing the fibers in hot, five-weight-percent sodium hydroxide solution until the concentration of dissolved silica reaches equilibrium and a only a residue is left (about 48 hours), then immersing the residue in hot, five-weight-percent nitric acid until the residue dissolves (about 96 hours). After adjusting the pH of the dissolved fibers to be caustic, the solution can then be added to a waste vitrification stream for safe disposal. The method is useful in disposing contaminated HEME and HEPA filters.

Hepatitis A vaccination coverage among adults 18-49 years traveling to a country of high or intermediate endemicity, United States.

PubMed

Lu, Peng-Jun; Byrd, Kathy K; Murphy, Trudy V

2013-05-01

Since 1996, hepatitis A vaccine (HepA) has been recommended for adults at increased risk for infection including travelers to high or intermediate hepatitis A endemic countries. In 2009, travel outside the United States and Canada was the most common exposure nationally reported for persons with hepatitis A virus (HAV) infection. To assess HepA vaccination coverage among adults 18-49 years traveling to a country of high or intermediate endemicity in the United States. We analyzed data from the 2010 National Health Interview Survey (NHIS), to determine self-reported HepA vaccination coverage (≥1 dose) and series completion (≥2 dose) among persons 18-49 years who traveled, since 1995, to a country of high or intermediate HAV endemicity. Multivariable logistic regression and predictive marginal analyses were conducted to identify factors independently associated with HepA vaccine receipt. In 2010, approximately 36.6% of adults 18-49 years reported traveling to high or intermediate hepatitis A endemic countries; among this group unadjusted HepA vaccination coverage was 26.6% compared to 12.7% among non-travelers (P-values<0.001) and series completion were 16.9% and 7.6%, respectively (P-values<0.001). On multivariable analysis among all respondents, travel status was an independent predictor of HepA coverage and series completion (both P-values<0.001). Among travelers, HepA coverage and series completion (≥2 doses) were higher for travelers 18-25 years (prevalence ratios 2.3, 2.8, respectively, P-values<0.001) and for travelers 26-39 years (prevalence ratios 1.5, 1.5, respectively, P-value<0.001, P-value=0.002, respectively) compared to travelers 40-49 years. Other characteristics independently associated with a higher likelihood of HepA receipt among travelers included Asian race/ethnicity, male sex, never having been married, having a high school or higher education, living in the western United States, having greater number of physician contacts or receipt of influenza vaccination in the previous year. HepB vaccination was excluded from the model because of the significant correlation between receipt of HepA vaccination and HepB vaccination could distort the model. Although travel to a country of high or intermediate hepatitis A endemicity was associated with higher likelihood of HepA vaccination in 2010 among adults 18-49 years, self-reported HepA vaccination coverage was low among adult travelers to these areas. Healthcare providers should ask their patients' upcoming travel plans and recommend and offer travel related vaccinations to their patients. Published by Elsevier Ltd.

Hepatitis A vaccination coverage among adults 18–49 years traveling to a country of high or intermediate endemicity, United States

PubMed Central

Lu, Peng-jun; Byrd, Kathy K.; Murphy, Trudy V.

2018-01-01

Background Since 1996, hepatitis A vaccine (HepA) has been recommended for adults at increased risk for infection including travelers to high or intermediate hepatitis A endemic countries. In 2009, travel outside the United States and Canada was the most common exposure nationally reported for persons with hepatitis A virus (HAV) infection. Objective To assess HepA vaccination coverage among adults 18–49 years traveling to a country of high or intermediate endemicity in the United States. Methods We analyzed data from the 2010 National Health Interview Survey (NHIS), to determine self-reported HepA vaccination coverage (≥1 dose) and series completion (≥2 dose) among persons 18–49 years who traveled, since 1995, to a country of high or intermediate HAV endemicity. Multivariable logistic regression and predictive marginal analyses were conducted to identify factors independently associated with HepA vaccine receipt. Results In 2010, approximately 36.6% of adults 18–49 years reported traveling to high or intermediate hepatitis A endemic countries; among this group unadjusted HepA vaccination coverage was 26.6% compared to 12.7% among non-travelers (P-values < 0.001) and series completion were 16.9% and 7.6%, respectively (P-values < 0.001). On multivariable analysis among all respondents, travel status was an independent predictor of HepA coverage and series completion (both P-values < 0.001). Among travelers, HepA coverage and series completion (≥2 doses) were higher for travelers 18–25 years (prevalence ratios 2.3, 2.8, respectively, P-values < 0.001) and for travelers 26–39 years (prevalence ratios 1.5, 1.5, respectively, P-value < 0.001, P-value = 0.002, respectively) compared to travelers 40–49 years. Other characteristics independently associated with a higher likelihood of HepA receipt among travelers included Asian race/ethnicity, male sex, never having been married, having a high school or higher education, living in the western United States, having greater number of physician contacts or receipt of influenza vaccination in the previous year. HepB vaccination was excluded from the model because of the significant correlation between receipt of HepA vaccination and HepB vaccination could distort the model. Conclusions Although travel to a country of high or intermediate hepatitis A endemicity was associated with higher likelihood of HepA vaccination in 2010 among adults 18–49 years, self-reported HepA vaccination coverage was low among adult travelers to these areas. Healthcare providers should ask their patients’ upcoming travel plans and recommend and offer travel related vaccinations to their patients. PMID:23523408

Evidence of Coal-Fly-Ash Toxic Chemical Geoengineering in the Troposphere: Consequences for Public Health.

PubMed

Herndon, J Marvin

2015-08-11

The widespread, intentional and increasingly frequent chemical emplacement in the troposphere has gone unidentified and unremarked in the scientific literature for years. The author presents evidence that toxic coal combustion fly ash is the most likely aerosolized particulate sprayed by tanker-jets for geoengineering, weather-modification and climate-modification purposes and describes some of the multifold consequences on public health. Two methods are employed: (1) Comparison of 8 elements analyzed in rainwater, leached from aerosolized particulates, with corresponding elements leached into water from coal fly ash in published laboratory experiments, and (2) Comparison of 14 elements analyzed in dust collected outdoors on a high-efficiency particulate air (HEPA) filter with corresponding elements analyzed in un-leached coal fly ash material. The results show: (1) the assemblage of elements in rainwater and in the corresponding experimental leachate are essentially identical. At a 99% confidence interval, they have identical means (T-test) and identical variances (F-test); and (2) the assemblage of elements in the HEPA dust and in the corresponding average un-leached coal fly ash are likewise essentially identical. The consequences on public health are profound, including exposure to a variety of toxic heavy metals, radioactive elements, and neurologically-implicated chemically mobile aluminum released by body moisture in situ after inhalation or through transdermal induction.

Nor-ursodeoxycholic acid reverses hepatocyte-specific nemo-dependent steatohepatitis.

PubMed

Beraza, Naiara; Ofner-Ziegenfuss, Lisa; Ehedego, Haksier; Boekschoten, Mark; Bischoff, Stephan C; Mueller, Michael; Trauner, Michael; Trautwein, Christian

2011-03-01

Hepatocyte-specific NEMO/NF-κB deleted mice (NEMO(Δhepa)) develop spontaneous non-alcoholic steatohepatitis (NASH). Free fatty acids and bile acids promote DR5 expression. TRAIL/NK cell-mediated activation of TRAIL-R2/DR5 plays an important role during acute injury in NEMO(Δhepa) mice. To inhibit the progression of NASH in the absence of hepatocyte-NEMO/NF-kB signaling. NEMOf/f and NEMO(Δhepa) mice were fed with a low-fat diet, and with two anticholestatic diets; UDCA and NorUDCA. The impact of these treatments on the progression of NASH was evaluated. We show that high expression of DR5 in livers from NEMO(Δhepa) mice is accompanied by an abundant presence of bile acids (BAs), misregulation of BA transporters and significant alteration of lipid metabolism-related genes. Additionally, mice lacking NEMO in hepatocytes spontaneously showed ductular response at young age. Unexpectedly, feeding of NEMO(Δhepa) mice with low-fat diet failed to improve chronic liver injury. Conversely, anti-cholestatic treatment with nor-ursodeoxycholic acid (NorUDCA), but not with ursodeoxycholic acid (UDCA), led to a significant attenuation of liver damage in NEMO(Δhepa) mice. The strong therapeutic effect of NorUDCA relied on a significant downregulation of LXR-dependent lipogenesis and the normalisation of BA metabolism through mechanisms involving cross-talk between Cyp7a1 and SHP. This was associated with the significant improvement of liver histology, NEMO(Δhepa)/NorUDCA-treated mice showed lower apoptosis and reduced CyclinD1 expression, indicating attenuation of the compensatory proliferative response to hepatocellular damage. Finally, fibrosis and ductular reaction markers were significantly reduced in NorUDCA-treated NEMO(Δhepa) mice. Overall, our work demonstrates the contribution of bile acids metabolism to the progression of NASH in the absence of hepatocyte-NF-kB through mechanisms involving DR5-apoptosis, inflammation and fibrosis. Our work suggests a potential therapeutic effect of NorUDCA in attenuating the progression of NASH.

Stable Overexpression of the Constitutive Androstane Receptor Reduces the Requirement for Culture with Dimethyl Sulfoxide for High Drug Metabolism in HepaRG Cells.

PubMed

van der Mark, Vincent A; Rudi de Waart, D; Shevchenko, Valery; Elferink, Ronald P J Oude; Chamuleau, Robert A F M; Hoekstra, Ruurdtje

2017-01-01

Dimethylsulfoxide (DMSO) induces cellular differentiation and expression of drug metabolic enzymes in the human liver cell line HepaRG; however, DMSO also induces cell death and interferes with cellular activities. The aim of this study was to examine whether overexpression of the constitutive androstane receptor (CAR, NR1I3), the nuclear receptor controlling various drug metabolism genes, would sufficiently promote differentiation and drug metabolism in HepaRG cells, optionally without using DMSO. By stable lentiviral overexpression of CAR, HepaRG cultures were less affected by DMSO in total protein content and obtained increased resistance to acetaminophen- and amiodarone-induced cell death. Transcript levels of CAR target genes were significantly increased in HepaRG-CAR cultures without DMSO, resulting in increased activities of cytochrome P450 (P450) enzymes and bilirubin conjugation to levels equal or surpassing those of HepaRG cells cultured with DMSO. Unexpectedly, CAR overexpression also increased the activities of non-CAR target P450s, as well as albumin production. In combination with DMSO treatment, CAR overexpression further increased transcript levels and activities of CAR targets. Induction of CYP1A2 and CYP2B6 remained unchanged, whereas CYP3A4 was reduced. Moreover, the metabolism of low-clearance compounds warfarin and prednisolone was increased. In conclusion, CAR overexpression creates a more physiologically relevant environment for studies on hepatic (drug) metabolism and differentiation in HepaRG cells without the utilization of DMSO. DMSO still may be applied to accomplish higher drug metabolism, required for sensitive assays, such as low-clearance studies and identification of (rare) metabolites, whereas reduced total protein content after DMSO culture is diminished by CAR overexpression. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Identifying Strategies Programs Adopt to Meet Healthy Eating and Physical Activity Standards in Afterschool Programs.

PubMed

Weaver, Robert G; Moore, Justin B; Turner-McGrievy, Brie; Saunders, Ruth; Beighle, Aaron; Khan, M Mahmud; Chandler, Jessica; Brazendale, Keith; Randell, Allison; Webster, Collin; Beets, Michael W

2017-08-01

The YMCA of USA has adopted Healthy Eating and Physical Activity (HEPA) Standards for its afterschool programs (ASPs). Little is known about strategies YMCA ASPs are implementing to achieve Standards and these strategies' effectiveness. (1) Identify strategies implemented in YMCA ASPs and (2) evaluate the relationship between strategy implementation and meeting Standards. HEPA was measured via accelerometer (moderate-to-vigorous-physical-activity [MVPA]) and direct observation (snacks served) in 20 ASPs. Strategies were identified and mapped onto a capacity building framework ( Strategies To Enhance Practice [STEPs]). Mixed-effects regression estimated increases in HEPA outcomes as implementation increased. Model-implied estimates were calculated for high (i.e., highest implementation score achieved), moderate (median implementation score across programs), and low (lowest implementation score achieved) implementation for both HEPA separately. Programs implemented a variety of strategies identified in STEPs. For every 1-point increase in implementation score 1.45% (95% confidence interval = 0.33% to 2.55%, p ≤ .001) more girls accumulated 30 min/day of MVPA and fruits and/or vegetables were served on 0.11 more days (95% confidence interval = 0.11-0.45, p ≤ .01). Relationships between implementation and other HEPA outcomes did not reach statistical significance. Still regression estimates indicated that desserts are served on 1.94 fewer days (i.e., 0.40 vs. 2.34) in the highest implementing program than the lowest implementing program and water is served 0.73 more days (i.e., 2.37 vs. 1.64). Adopting HEPA Standards at the national level does not lead to changes in routine practice in all programs. Practical strategies that programs could adopt to more fully comply with the HEPA Standards are identified.

Comparative Proteomics Reveals Novel Components at the Plasma Membrane of Differentiated HepaRG Cells and Different Distribution in Hepatocyte- and Biliary-Like Cells

PubMed Central

Woods, Alisa G.; Lazar, Catalin; Radu, Gabriel L.; Darie, Costel C.; Branza-Nichita, Norica

2013-01-01

Hepatitis B virus (HBV) is a human pathogen causing severe liver disease and eventually death. Despite important progress in deciphering HBV internalization, the early virus-cell interactions leading to infection are not known. HepaRG is a human bipotent liver cell line bearing the unique ability to differentiate towards a mixture of hepatocyte- and biliary-like cells. In addition to expressing metabolic functions normally found in liver, differentiated HepaRG cells support HBV infection in vitro, thus resembling cultured primary hepatocytes more than other hepatoma cells. Therefore, extensive characterization of the plasma membrane proteome from HepaRG cells would allow the identification of new cellular factors potentially involved in infection. Here we analyzed the plasma membranes of non-differentiated and differentiated HepaRG cells using nanoliquid chromatography-tandem mass spectrometry to identify the differences between the proteomes and the changes that lead to differentiation of these cells. We followed up on differentially-regulated proteins in hepatocytes- and biliary-like cells, focusing on Cathepsins D and K, Cyclophilin A, Annexin 1/A1, PDI and PDI A4/ERp72. Major differences between the two proteomes were found, including differentially regulated proteins, protein-protein interactions and intracellular localizations following differentiation. The results advance our current understanding of HepaRG differentiation and the unique properties of these cells. PMID:23977166

Comparative proteomics reveals novel components at the plasma membrane of differentiated HepaRG cells and different distribution in hepatocyte- and biliary-like cells.

PubMed

Petrareanu, Catalina; Macovei, Alina; Sokolowska, Izabela; Woods, Alisa G; Lazar, Catalin; Radu, Gabriel L; Darie, Costel C; Branza-Nichita, Norica

2013-01-01

Hepatitis B virus (HBV) is a human pathogen causing severe liver disease and eventually death. Despite important progress in deciphering HBV internalization, the early virus-cell interactions leading to infection are not known. HepaRG is a human bipotent liver cell line bearing the unique ability to differentiate towards a mixture of hepatocyte- and biliary-like cells. In addition to expressing metabolic functions normally found in liver, differentiated HepaRG cells support HBV infection in vitro, thus resembling cultured primary hepatocytes more than other hepatoma cells. Therefore, extensive characterization of the plasma membrane proteome from HepaRG cells would allow the identification of new cellular factors potentially involved in infection. Here we analyzed the plasma membranes of non-differentiated and differentiated HepaRG cells using nanoliquid chromatography-tandem mass spectrometry to identify the differences between the proteomes and the changes that lead to differentiation of these cells. We followed up on differentially-regulated proteins in hepatocytes- and biliary-like cells, focusing on Cathepsins D and K, Cyclophilin A, Annexin 1/A1, PDI and PDI A4/ERp72. Major differences between the two proteomes were found, including differentially regulated proteins, protein-protein interactions and intracellular localizations following differentiation. The results advance our current understanding of HepaRG differentiation and the unique properties of these cells.

Invasive aspergillosis in severely neutropenic patients over 18 years: impact of intranasal amphotericin B and HEPA filtration.

PubMed

Withington, S; Chambers, S T; Beard, M E; Inder, A; Allen, J R; Ikram, R B; Schousboe, M I; Heaton, D C; Spearing, R I; Hart, D N

1998-01-01

The impact of intranasal amphotericin B and high-efficiency particulate air (HEPA) filtration on the incidence of invasive aspergillosis was reviewed in patients from 1977 to 1994 undergoing intensive chemotherapy. Overall, the incidence of proven invasive aspergillosis was reduced from 24.4% (1977-1984) to 7.1% (1985-1991) (P < 0.001) following the introduction of intranasal prophylaxis, but when probable cases of aspergillosis were included and lymphoma cases excluded, there was no change in incidence. Following the introduction of HEPA filtration, patient exposure to aspergillus spores as measured by air sampling was markedly reduced and there were no new cases of invasive aspergillosis. HEPA filtration proved effective in reducing invasive aspergillosis and has allowed increasingly aggressive treatment regimens to be introduced.

Loading and unloading of freeze-dryers: airborne contamination risks for aseptically manufactured sterile drug products.

PubMed

Ljungqvist, Bengt; Reinmüller, Berit

2007-01-01

In pharmaceutical manufacturing, freeze-drying processes can be adversely affected by temperature differences relative to the surrounding air. Loading and unloading of freeze-dryers are performed either without or with temperature differences between the cleanroom and the chamber of the freeze-dryer. This operation can cause a flow of room air through the opening, creating a contamination risk, especially when manual handling of material is performed in this area. To minimize this risk, a high-efficiency particulate air (HEPA) filter unit should be installed above the opening to provide clean air and protect the opening. Here the theoretical relationships are discussed and design criteria are presented.

Method for dissolution and stabilization of silica-rich fibers

DOEpatents

Jantzen, C.M.

1997-11-11

A method is described for dissolving silica-rich fibers such as borosilicate fibers, fiberglass and asbestos to stabilize them for disposal. The method comprises (1) immersing the fibers in hot, five-weight-percent sodium hydroxide solution until the concentration of dissolved silica reaches equilibrium and a only a residue is left (about 48 hours), then immersing the residue in hot, five-weight-percent nitric acid until the residue dissolves (about 96 hours). After adjusting the pH of the dissolved fibers to be caustic, the solution can then be added to a waste vitrification stream for safe disposal. The method is useful in disposing contaminated HEME and HEPA filters. 1 fig.

Mold Species in Dust from the International Space Station Identified and Quantified by Mold Specific Quantitative PCR

NASA Technical Reports Server (NTRS)

Vesper, Stephen J.; Wong, Wing; Kuo, C. Mike; Pierson, Duane L.

2008-01-01

Dust was collected over a period of several weeks in 2007 from various HEPA filters in the U.S. Laboratory Module of the International Space Station (ISS). The dust was returned on the Space Shuttle Atlantis, mixed, sieved, and the DNA was extracted. Using a DNA-based method called mold specific quantitative PCR (MSQPCR), 39 molds were measured in the dust. Opportunistic pathogens Aspergillus flavus and A. niger and toxin producers Penicillium chrysogenum and P. brevicompactum were found at relatively high concentrations (compared to U.S. homes). No cells of the opportunistic pathogens A. fumigatus, A. terreus, Fusarium solani or Candida albicans were detected.

Hybrid Filter Membrane

NASA Technical Reports Server (NTRS)

Laicer, Castro; Rasimick, Brian; Green, Zachary

2012-01-01

Cabin environmental control is an important issue for a successful Moon mission. Due to the unique environment of the Moon, lunar dust control is one of the main problems that significantly diminishes the air quality inside spacecraft cabins. Therefore, this innovation was motivated by NASA s need to minimize the negative health impact that air-suspended lunar dust particles have on astronauts in spacecraft cabins. It is based on fabrication of a hybrid filter comprising nanofiber nonwoven layers coated on porous polymer membranes with uniform cylindrical pores. This design results in a high-efficiency gas particulate filter with low pressure drop and the ability to be easily regenerated to restore filtration performance. A hybrid filter was developed consisting of a porous membrane with uniform, micron-sized, cylindrical pore channels coated with a thin nanofiber layer. Compared to conventional filter media such as a high-efficiency particulate air (HEPA) filter, this filter is designed to provide high particle efficiency, low pressure drop, and the ability to be regenerated. These membranes have well-defined micron-sized pores and can be used independently as air filters with discreet particle size cut-off, or coated with nanofiber layers for filtration of ultrafine nanoscale particles. The filter consists of a thin design intended to facilitate filter regeneration by localized air pulsing. The two main features of this invention are the concept of combining a micro-engineered straight-pore membrane with nanofibers. The micro-engineered straight pore membrane can be prepared with extremely high precision. Because the resulting membrane pores are straight and not tortuous like those found in conventional filters, the pressure drop across the filter is significantly reduced. The nanofiber layer is applied as a very thin coating to enhance filtration efficiency for fine nanoscale particles. Additionally, the thin nanofiber coating is designed to promote capture of dust particles on the filter surface and to facilitate dust removal with pulse or back airflow.

HepaRG human hepatic cell line utility as a surrogate for primary human hepatocytes in drug metabolism assessment in vitro.

PubMed

Lübberstedt, Marc; Müller-Vieira, Ursula; Mayer, Manuela; Biemel, Klaus M; Knöspel, Fanny; Knobeloch, Daniel; Nüssler, Andreas K; Gerlach, Jörg C; Zeilinger, Katrin

2011-01-01

Primary human hepatocytes are considered as a highly predictive in vitro model for preclinical drug metabolism studies. Due to the limited availability of human liver tissue for cell isolation, there is a need of alternative cell sources for pharmaceutical research. In this study, the metabolic activity and long-term stability of the human hepatoma cell line HepaRG were investigated in comparison to primary human hepatocytes (pHH). Hepatocyte-specific parameters (albumin and urea synthesis, galactose and sorbitol elimination) and the activity of human-relevant cytochrome P450 (CYP) enzymes (CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4) were assayed in both groups over a period of 14 days subsequently to a two week culture period in differentiated state in case of the HepaRG cells, and compared with those of cryopreserved hepatocytes in suspension. In addition, the inducibility of CYP enzymes and the intrinsic clearances of eleven reference drugs were determined. The results show overall stable metabolic activity of HepaRG cells over the monitored time period. Higher albumin production and galactose/sorbitol elimination rates were observed compared with pHH, while urea production was not detected. CYP enzyme-dependent drug metabolic capacities were shown to be stable over the cultivation time in HepaRG cells and were comparable or even higher (CYP2C9, CYP2D6, CYP3A4) than in pHH, whereas commercially available hepatocytes showed a different pattern The intrinsic clearance rates of reference drugs and enzyme induction of most CYP enzymes were similar in HepaRG cells and pHH. CYP1A2 activity was highly inducible in HepaRG by β-naphthoflavone. In conclusion, the results from this study indicate that HepaRG cells could provide a suitable alternative to pHH in pharmaceutical research and development for metabolism studies such as CYP induction or sub-chronic to chronic hepatotoxicity studies. Copyright © 2010 Elsevier Inc. All rights reserved.

Development of a Repeatable Protocol to Uniformly Coat Internal Complex Geometries of Fine Featured 3D Printed Objects with Ceramic Material, including Determination of Viscosity Limits to Properly Coat Certain Pore Sizes

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

Rogers, A.

HEPA filters are commonly used in air filtration systems ranging in application from simple home systems to the more advanced networks used in research and development. Currently, these filters are most often composed of glass fibers with diameter on the order of one micron with polymer binders. These fibers, as well as the polymers used, are known to be fragile and can degrade or become extremely brittle with heat, severely limiting their use in high temperature applications. Ceramics are one promising alternative and can enhance the filtration capabilities compared to the current technology. Because ceramic materials are more thermally resistantmore » and chemically stable, there is great interest in developing a repeatable protocol to uniformly coat fine featured polymer objects with ceramic material for use as a filter. The purpose of this experiment is to determine viscosity limits that are able to properly coat certain pore sizes in 3D printed objects, and additionally to characterize the coatings themselves. Latex paint was used as a surrogate because it is specifically designed to produce uniform coatings.« less

Evidence of Coal-Fly-Ash Toxic Chemical Geoengineering in the Troposphere: Consequences for Public Health

PubMed Central

Herndon, J. Marvin

2015-01-01

The widespread, intentional and increasingly frequent chemical emplacement in the troposphere has gone unidentified and unremarked in the scientific literature for years. The author presents evidence that toxic coal combustion fly ash is the most likely aerosolized particulate sprayed by tanker-jets for geoengineering, weather-modification and climate-modification purposes and describes some of the multifold consequences on public health. Two methods are employed: (1) Comparison of 8 elements analyzed in rainwater, leached from aerosolized particulates, with corresponding elements leached into water from coal fly ash in published laboratory experiments, and (2) Comparison of 14 elements analyzed in dust collected outdoors on a high-efficiency particulate air (HEPA) filter with corresponding elements analyzed in un-leached coal fly ash material. The results show: (1) the assemblage of elements in rainwater and in the corresponding experimental leachate are essentially identical. At a 99% confidence interval, they have identical means (T-test) and identical variances (F-test); and (2) the assemblage of elements in the HEPA dust and in the corresponding average un-leached coal fly ash are likewise essentially identical. The consequences on public health are profound, including exposure to a variety of toxic heavy metals, radioactive elements, and neurologically-implicated chemically mobile aluminum released by body moisture in situ after inhalation or through transdermal induction. PMID:26270671

Rapid fabricating technique for multi-layered human hepatic cell sheets by forceful contraction of the fibroblast monolayer.

PubMed

Sakai, Yusuke; Koike, Makiko; Hasegawa, Hideko; Yamanouchi, Kosho; Soyama, Akihiko; Takatsuki, Mitsuhisa; Kuroki, Tamotsu; Ohashi, Kazuo; Okano, Teruo; Eguchi, Susumu

2013-01-01

Cell sheet engineering is attracting attention from investigators in various fields, from basic research scientists to clinicians focused on regenerative medicine. However, hepatocytes have a limited proliferation potential in vitro, and it generally takes a several days to form a sheet morphology and multi-layered sheets. We herein report our rapid and efficient technique for generating multi-layered human hepatic cell (HepaRG® cell) sheets using pre-cultured fibroblast monolayers derived from human skin (TIG-118 cells) as a feeder layer on a temperature-responsive culture dish. Multi-layered TIG-118/HepaRG cell sheets with a thick morphology were harvested on day 4 of culturing HepaRG cells by forceful contraction of the TIG-118 cells, and the resulting sheet could be easily handled. In addition, the human albumin and alpha 1-antitrypsin synthesis activities of TIG-118/HepaRG cells were approximately 1.2 and 1.3 times higher than those of HepaRG cells, respectively. Therefore, this technique is considered to be a promising modality for rapidly fabricating multi-layered human hepatocyte sheets from cells with limited proliferation potential, and the engineered cell sheet could be used for cell transplantation with highly specific functions.

Mitigation of radon and thoron decay products by filtration.

PubMed

Wang, Jin; Meisenberg, Oliver; Chen, Yongheng; Karg, Erwin; Tschiersch, Jochen

2011-09-01

Inhalation of indoor radon ((222)Rn) and thoron ((220)Rn) decay products is the most important source of exposure to ionizing radiation for the human respiratory tract. Decreasing ventilation rates due to energy saving reasons in new buildings suggest additional active mitigation techniques to reduce the exposure in homes with high radon and thoron concentrations but poor ventilation. Filtration techniques with HEPA filters and simple surgical mask material have been tested for their potential to reduce the indoor exposure in terms of the total effective dose for mixed radon and thoron indoor atmospheres. The tests were performed inside an experimental room providing stable conditions. Filtration (at filtration rates of 0.2 h(-1) and larger) removes attached radon and thoron decay products effectively but indoor aerosol as well. Therefore the concentration of unattached decay products (which have a higher dose coefficient) may increase. The decrease of the attached decay product concentrations could be theoretically described by a slowly decreasing exponential process. For attached radon decay products, it exhibited a faster but weaker removal process compared to attached thoron decay products (-70% for attached radon decay products and -80% for attached thoron decay products at a filtration rate of 0.5 h(-1) with an HEPA filter). The concentration of unattached thoron decay products increased distinctly during the filtration process (+300%) while that of unattached radon decay products rose only slightly though at a much higher level (+17%). In the theoretical description these observed differences could be attributed to the different half-lives of the nuclides. Considering both effects, reduced attached and increased unattached decay product concentrations, filtration could significantly decrease the total effective dose from thoron whereas the overall effect on radon dose is small. A permanent filtration is recommended because of the slow decrease of the thoron decay product concentrations. Copyright © 2011 Elsevier B.V. All rights reserved.

The impact of onsite workplace health-enhancing physical activity interventions on worker productivity: a systematic review.

PubMed

Pereira, Michelle Jessica; Coombes, Brooke Kaye; Comans, Tracy Anne; Johnston, Venerina

2015-06-01

The aim of this study is to investigate the effects of onsite workplace health-enhancing physical activity (HEPA) programmes on worker productivity. The PROSPERO registration number is CRD42014008750. A search for controlled trials or randomised controlled trials (RCTs) that investigated the effects of onsite workplace HEPA programmes on productivity levels of working adults was performed. Risk of bias of included studies was assessed, and the inter-rater reliability of the quality assessment was analysed. Qualitative synthesis of available evidence is presented. Eight studies were included in the review. There is consistent evidence that onsite workplace HEPA programmes do not reduce levels of sick leave. There appears to be inconsistent evidence of the impact of onsite workplace HEPA programmes on worker productivity. A high-quality study of an onsite combination (aerobic, strengthening and flexibility) HEPA regime and a moderate-quality study of a Tai Chi programme improved worker productivity measured with questionnaires in female laundry workers and older female nurses, respectively. Two high-quality studies and four moderate-quality studies did not show benefit. Studies that showed benefit were mainly those designed with productivity measures as primary outcomes, delivered to occupations involved with higher physical loads, and had higher compliance and programme intensity. The small number of studies and the lack of consistency among studies limited further analyses. There is inconsistent evidence that onsite workplace HEPA programmes improve self-reported worker productivity. Future high-quality RCTs of onsite workplace HEPA programmes should be designed around productivity outcomes, target at-risk groups and investigate interventions of sufficient intensity. High attendance with improved recording is needed to achieve significant results in augmenting worker productivity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Synergistic anticancer effects of curcumin and resveratrol in Hepa1-6 hepatocellular carcinoma cells.

PubMed

Du, Qin; Hu, Bing; An, Hong-Mei; Shen, Ke-Ping; Xu, Ling; Deng, Shan; Wei, Meng-Meng

2013-05-01

Hepatocellular carcinoma remains one of the most prevalent malignancies worldwide. Curcuma aromatica and Polygonum cuspidatum are one of the commonly used paired-herbs for liver cancer treatment. Curcumin and resveratrol are the major anticancer constituents of Curcuma aromatica and Polygonum cuspidatum, respectively. Curcumin and resveratrol have been found to exhibit a synergistic anticancer effect in colon cancer. However, the combined effect of curcumin and resveratrol against hepatocellular carcinoma remains unknown. In the present study, we evaluated the combined effects of curcumin and resveratrol in hepatocellular carcinoma Hepa1-6 cells. The results showed that curcumin and resveratrol significantly inhibited the proliferation of Hepa1-6 cells in a dose- and time-dependent manner. The combination treatment of curcumin and resveratrol elicited a synergistic antiproliferative effect in Hepa1-6 cells. The apoptosis of Hepa1-6 cells induced by the combination treatment with curcumin and resveratrol was accompanied by caspase-3, -8 and -9 activation, which was completely abrogated by a pan caspase inhibitor, Z-VAD-FMK. Combination of curcumin and resveratrol upregulated intracellular reactive oxygen species (ROS) levels in Hepa1-6 cells. The ROS scavenger, NAC, partially attenuated the apoptosis and caspase activation induced by the combination treatment of curcumin and resveratrol. In addition, the combination of curcumin and resveratrol downregulated XIAP and survivin expression. These data suggest that the combination treatment of curcumin and resveratrol is a promising novel anticancer strategy for liver cancer. The present study also provides new insights into the effective mechanism of paired-herbs in traditional Chinese medicine.

Applied patent RFID systems for building reacting HEPA air ventilation system in hospital operation rooms.

PubMed

Lin, Jesun; Pai, Jar-Yuan; Chen, Chih-Cheng

2012-12-01

RFID technology, an automatic identification and data capture technology to provide identification, tracing, security and so on, was widely applied to healthcare industry in these years. Employing HEPA ventilation system in hospital is a way to ensure healthful indoor air quality to protect patients and healthcare workers against hospital-acquired infections. However, the system consumes lots of electricity which cost a lot. This study aims to apply the RFID technology to offer a unique medical staff and patient identification, and reacting HEPA air ventilation system in order to reduce the cost, save energy and prevent the prevalence of hospital-acquired infection. The system, reacting HEPA air ventilation system, contains RFID tags (for medical staffs and patients), sensor, and reacting system which receives the information regarding the number of medical staff and the status of the surgery, and controls the air volume of the HEPA air ventilation system accordingly. A pilot program was carried out in a unit of operation rooms of a medical center with 1,500 beds located in central Taiwan from Jan to Aug 2010. The results found the air ventilation system was able to function much more efficiently with less energy consumed. Furthermore, the indoor air quality could still keep qualified and hospital-acquired infection or other occupational diseases could be prevented.

Rapid Fabricating Technique for Multi-Layered Human Hepatic Cell Sheets by Forceful Contraction of the Fibroblast Monolayer

PubMed Central

Sakai, Yusuke; Koike, Makiko; Hasegawa, Hideko; Yamanouchi, Kosho; Soyama, Akihiko; Takatsuki, Mitsuhisa; Kuroki, Tamotsu; Ohashi, Kazuo; Okano, Teruo; Eguchi, Susumu

2013-01-01

Cell sheet engineering is attracting attention from investigators in various fields, from basic research scientists to clinicians focused on regenerative medicine. However, hepatocytes have a limited proliferation potential in vitro, and it generally takes a several days to form a sheet morphology and multi-layered sheets. We herein report our rapid and efficient technique for generating multi-layered human hepatic cell (HepaRG® cell) sheets using pre-cultured fibroblast monolayers derived from human skin (TIG-118 cells) as a feeder layer on a temperature-responsive culture dish. Multi-layered TIG-118/HepaRG cell sheets with a thick morphology were harvested on day 4 of culturing HepaRG cells by forceful contraction of the TIG-118 cells, and the resulting sheet could be easily handled. In addition, the human albumin and alpha 1-antitrypsin synthesis activities of TIG-118/HepaRG cells were approximately 1.2 and 1.3 times higher than those of HepaRG cells, respectively. Therefore, this technique is considered to be a promising modality for rapidly fabricating multi-layered human hepatocyte sheets from cells with limited proliferation potential, and the engineered cell sheet could be used for cell transplantation with highly specific functions. PMID:23923035

A novel multiplex real-time PCR assay for the concurrent detection of hepatitis A, B and C viruses in patients with acute hepatitis.

PubMed

Park, Yongjung; Kim, Beom Seok; Choi, Kyu Hun; Shin, Dong Ho; Lee, Mi Jung; Cho, Yonggeun; Kim, Hyon-Suk

2012-01-01

A novel multiplex real-time PCR assay for concurrent detection of hepatitis viruses was evaluated for its clinical performance in screening patients with acute hepatitis. A total of 648 serum samples were collected from patients with acute symptoms of hepatitis. Concurrent detection of nucleic acids of HAV, HBV and HCV was performed using the Magicplex™ HepaTrio Real-time Detection test. Serum nucleic acid levels of HBV and HCV were also quantified by the Cobas® AmpliPrep/Cobas® TaqMan® (CAP/CTM) HBV and HCV tests. Patients' medical records were also reviewed. Concordance rates between the results from the HepaTrio and the CAP/CTM tests for the detection of HBV and HCV were 94.9% (k = 0.88) and 99.2% (k = 0.98), respectively. The cycle threshold values with the HepaTrio test were also correlated well with the levels of HBV DNA (r = -0.9230) and HCV RNA (r = -0.8458). The sensitivity and specificity of the HepaTrio test were 93.8% and 98.2%, respectively, for detecting HBV infection, and 99.1% and 100.0%, respectively, for HCV infection. For the HepaTrio test, 21 (3.2%) cases were positive for both HBV and HCV. Among the positive cases, 6 (0.9%) were true coinfections. This test also detected 18 (2.8%) HAV positives. The HepaTrio test demonstrated good clinical performance and produced results that agreed well with those of the CAP/CTM assays, especially for the detection of HCV. This assay was also able to detect HAV RNA from anti-HAV IgM-positive individuals. Therefore, this new multiplex PCR assay could be useful for the concurrent detection of the three hepatitis viruses.

Turning the tide: national policy approaches to increasing physical activity in seven European countries.

PubMed

Bull, Fiona; Milton, Karen; Kahlmeier, Sonja; Arlotti, Alberto; Juričan, Andrea Backović; Belander, Olov; Martin, Brian; Martin-Diener, Eva; Marques, Ana; Mota, Jorge; Vasankari, Tommi; Vlasveld, Anita

2015-06-01

Physical inactivity is one of the four leading behavioural risk factors for non-communicable disease (NCD). Like tobacco control, increasing levels of health-enhancing physical activity (HEPA) will require a national policy framework providing direction and a clear set of actions. Despite frequent calls, there has been insufficient progress on policy development in the majority of countries around the world. This study sought and summarised national HEPA policy in seven European countries (Finland, Italy, the Netherlands, Norway, Portugal, Slovenia and Switzerland). Data collection used a policy audit tool (PAT), a 27-item instrument structured into four sections. All countries reported some legislation or policy across the sectors of education, sport and health. Only some countries reported supportive policy in the transport and environment sectors. Five countries reported a stand-alone HEPA policy and six countries reported national recommendations. HEPA prevalence targets varied in magnitude and specificity and the presence of other relevant goals from different sectors highlighted the opportunity for joint action. Evaluation and the use of scientific evidence were endorsed but described as weak in practice. Only two countries reported a national multisector coordinating committee and most countries reported challenges with partnerships on different levels of policy implementation. Bringing together the key components for success within a national HEPA policy framework is not simple. This in-depth policy audit and country comparison highlighted similarities and differences and revealed new opportunities for consideration by other countries. These examples can inform countries within and beyond Europe and guide the development of national HEPA policy within the NCD prevention agenda. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Hepatitis A and Hepatitis B vaccination coverage among adults with chronic liver disease

PubMed Central

Yue, Xin; Black, Carla L.; O’Halloran, Alissa; Lu, Peng-Jun; Williams, Walter W.; Nelson, Noele P.

2018-01-01

Background Infection with hepatitis A and hepatitis B virus can increase the risk of morbidity and mortality in persons with chronic liver disease (CLD). The Advisory Committee on Immunization Practices recommends hepatitis A (HepA) and hepatitis B (HepB) vaccination for persons with CLD. Methods Data from the 2014 and 2015 National Health Interview Surveys (NHIS), nationally representative, in-person interview surveys of the non-institutionalized US civilian population, were used to assess self-reported HepA (≥1 and ≥2 doses) and HepB vaccination (≥1 and ≥3 doses) coverage among adults who reported a chronic or long-term liver condition. Multivariable logistic regression was used to identify factors independently associated with HepA and HepB vaccination among adults with CLD. Results Overall, 19.4% and 11.5% of adults aged ≥18 years with CLD reported receiving ≥1 dose and ≥2 doses of HepA vaccine, respectively, compared with 14.7% and 9.1% of adults without CLD (p<0.05 comparing those with and without CLD, ≥1dose). Age, education, geographic region, and international travel were associated with receipt of ≥2 doses HepA vaccine among adults with CLD. Overall, 35.7% and 29.1% of adults with CLD reported receiving ≥1 dose and ≥3 doses of HepB vaccine, respectively, compared with 30.2% and 24.7% of adults without CLD (p<0.05 comparing those with and without CLD, ≥1 dose). Age, education, and receipt of influenza vaccination in the past 12 months were associated with receipt of ≥3 doses HepB vaccine among adults with CLD. Among adults with CLD and ≥10 provider visits, only 13.8% and 35.3% had received ≥2 doses HepA and ≥3 doses HepB vaccine, respectively. Conclusions HepA and HepB vaccination among adults with CLD is suboptimal and missed opportunities to vaccinate occurred. Providers should adhere to recommendations to vaccinate persons with CLD to increase vaccination among this population. PMID:29395521

Hepatitis A and hepatitis B vaccination coverage among adults with chronic liver disease.

PubMed

Yue, Xin; Black, Carla L; O'Halloran, Alissa; Lu, Peng-Jun; Williams, Walter W; Nelson, Noele P

2018-02-21

Infection with hepatitis A and hepatitis B virus can increase the risk of morbidity and mortality in persons with chronic liver disease (CLD). The Advisory Committee on Immunization Practices recommends hepatitis A (HepA) and hepatitis B (HepB) vaccination for persons with CLD. Data from the 2014 and 2015 National Health Interview Surveys (NHIS), nationally representative, in-person interview surveys of the non-institutionalized US civilian population, were used to assess self-reported HepA (≥1 and ≥2 doses) and HepB vaccination (≥1 and ≥3 doses) coverage among adults who reported a chronic or long-term liver condition. Multivariable logistic regression was used to identify factors independently associated with HepA and HepB vaccination among adults with CLD. Overall, 19.4% and 11.5% of adults aged ≥ 18 years with CLD reported receiving ≥1 dose and ≥2 doses of HepA vaccine, respectively, compared with 14.7% and 9.1% of adults without CLD (p < .05 comparing those with and without CLD, ≥1dose). Age, education, geographic region, and international travel were associated with receipt of ≥2 doses HepA vaccine among adults with CLD. Overall, 35.7% and 29.1% of adults with CLD reported receiving ≥1 dose and ≥3 doses of HepB vaccine, respectively, compared with 30.2% and 24.7% of adults without CLD (p < .05 comparing those with and without CLD, ≥1 dose). Age, education, and receipt of influenza vaccination in the past 12 months were associated with receipt of ≥3 doses HepB vaccine among adults with CLD. Among adults with CLD and ≥10 provider visits, only 13.8% and 35.3% had received ≥2 doses HepA and ≥3 doses HepB vaccine, respectively. HepA and HepB vaccination among adults with CLD is suboptimal and missed opportunities to vaccinate occurred. Providers should adhere to recommendations to vaccinate persons with CLD to increase vaccination among this population. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

Poppiti, James; Nelson, Roger; MacMillan, Walter J.

The Waste Isolation Pilot Plant (WIPP) is a 655-meter deep mine near Carlsbad, New Mexico, used to dispose the nation’s defense transuranic waste. Limited airborne radioactivity was released from a container of radioactive waste in WIPP on 14 February, 2014. As designed, a mine ventilation filtration system prevented the large scale release of contamination from the underground. However, isolation dampers leaked, which allowed the release of low levels of contaminants after the event until they were sealed. None of the exposed individuals received any recordable dose. While surface contamination was limited, contamination in the ventilation system and portions of themore » underground was substantial. High efficiency particulate air (HEPA) filters in the operating ventilation system ensure continued containment during recovery and resumption of disposal operations. However, ventilation flow is restricted since the incident, with all exhaust air directed through the filters. Decontamination and natural fixation by the hygroscopic nature of the salt host rock has reduced the likelihood of further contamination spread. Contamination control and ventilation system operability are crucial for resumption of operations. This article provides an operational assessment and evaluation of these two key areas.« less

24 CFR 35.140 - Prohibited methods of paint removal.

Code of Federal Regulations, 2011 CFR

2011-04-01

... air (HEPA) local exhaust control. (c) Abrasive blasting or sandblasting without HEPA local exhaust control. (d) Heat guns operating above 1100 degrees Fahrenheit or charring the paint. (e) Dry sanding or dry scraping, except dry scraping in conjunction with heat guns or within 1.0 ft. (0.30 m.) of...

24 CFR 35.140 - Prohibited methods of paint removal.

Code of Federal Regulations, 2013 CFR

2013-04-01

... air (HEPA) local exhaust control. (c) Abrasive blasting or sandblasting without HEPA local exhaust control. (d) Heat guns operating above 1100 degrees Fahrenheit or charring the paint. (e) Dry sanding or dry scraping, except dry scraping in conjunction with heat guns or within 1.0 ft. (0.30 m.) of...

24 CFR 35.140 - Prohibited methods of paint removal.

Code of Federal Regulations, 2012 CFR

2012-04-01

... air (HEPA) local exhaust control. (c) Abrasive blasting or sandblasting without HEPA local exhaust control. (d) Heat guns operating above 1100 degrees Fahrenheit or charring the paint. (e) Dry sanding or dry scraping, except dry scraping in conjunction with heat guns or within 1.0 ft. (0.30 m.) of...

24 CFR 35.140 - Prohibited methods of paint removal.

Code of Federal Regulations, 2014 CFR

2014-04-01

... air (HEPA) local exhaust control. (c) Abrasive blasting or sandblasting without HEPA local exhaust control. (d) Heat guns operating above 1100 degrees Fahrenheit or charring the paint. (e) Dry sanding or dry scraping, except dry scraping in conjunction with heat guns or within 1.0 ft. (0.30 m.) of...

Compliance with the Aerospace MACT Standard at Lockheed Martin

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

Kurucz, K.L.; Vicars, S.; Fetter, S.

1997-12-31

Actions taken and planned at four Lockheed Martin Corporation (LMC) facilities to comply with the Aerospace MACT Standard are reviewed. Many LMC sites have taken proactive steps to reduce emissions and implement low VOC coating technology. Significant administrative, facility, and material challenges remain to achieve compliance with the upcoming NESHAP and Control Technology Guideline (CTG) standards. The facilities discussed herein set up programs to develop and implement compliance strategies. These facilities manufacture military aircraft, missiles, satellites, rockets, and electronic guidance and communications systems. Some of the facilities are gearing up for new production lines subject to new source MACT standards.more » At this time the facilities are reviewing compliance status of all primers, topcoats, maskants and solvents subject to the standard. Facility personnel are searching for the most efficient methods of satisfying the recordkeeping, reporting and monitoring, sections of the standards while simultaneously preparing or reviewing their Title V permit applications. Facility decisions on paint booths are the next highest priority. Existing dry filter paint booths will be subject to the filtration standard for existing paint booths which requires the use of two-stage filters. Planned paint booths for the F-22 program, and other new booths must comply with the standard for new and rebuilt booths which requires three stage or HEPA filters. Facilities looking to replace existing water wash paint booths, and those required to retrofit the air handling equipment to accommodate the two-stage filters, are reviewing issues surrounding the rebuilt source definition.« less

Use of the HepaRG Cell Line to Assess Potential Human Hepatotoxicity of ToxCast™ Chemicals

EPA Science Inventory

The HepaRG cell line is a promising model system for predicting human hepatotoxicity in part because of the greater capacity to metabolize chemicals than other cell models. We hypothesized that this cell line would be a relevant model for toxicity testing of industrial chemicals....

MicroRNA Responses to the Genotoxic Carcinogens Aflatoxin B1 and Benzo[a]pyrene in Human HepaRG Cells.

PubMed

Marrone, April K; Tryndyak, Volodymyr; Beland, Frederick A; Pogribny, Igor P

2016-02-01

Recent advances in toxicogenomics present an opportunity to develop new in vitro testing methodologies to identify human carcinogens. We have investigated microRNA expression responses to the treatment of human liver HepaRG cells with the human genotoxic carcinogens aflatoxin B1 (AFB1) and benzo[a]pyrene (B[a]P), and the structurally similar compounds aflatoxin B2 (AFB2) and benzo[e]pyrene (B[e]P) that exhibit minimal carcinogenic potential. We demonstrate that treatment of HepaRG cells with AFB1 or B[a]P resulted in specific changes in the expression of miRNAs as compared with their non-carcinogenic analogues, particularly in a marked over-expression of miR-410. An additional novel finding is the dose- and time-dependent inhibition of miR-122 in AFB1-treated HepaRG cells. Mechanistically, the AFB1-induced down-regulation of miR-122 was attributed to inhibition of the HNF4A/miR-122 regulatory pathway. These results demonstrate that HepaRG cells can be used to investigate miRNA responses to xenobiotic exposure, and illustrate the existence of early non-genotoxic events, in addition to a well-established genotoxic mode of action changes, in the mechanism of AFB1 and B[a]P carcinogenicity. Published by Oxford University Press on behalf of the Society of Toxicology 2015. This work is written by US Government employees and is in the public domain in the US.

Unravelling networks in local public health policymaking in three European countries - a systems analysis.

PubMed

Spitters, Hilde P E M; Lau, Cathrine J; Sandu, Petru; Quanjel, Marcel; Dulf, Diana; Glümer, Charlotte; van Oers, Hans A M; van de Goor, Ien A M

2017-02-03

Facilitating and enhancing interaction between stakeholders involved in the policymaking process to stimulate collaboration and use of evidence, is important to foster the development of effective Health Enhancing Physical Activity (HEPA) policies. Performing an analysis of real-world policymaking processes will help reveal the complexity of a network of stakeholders. Therefore, the main objectives were to unravel the stakeholder network in the policy process by conducting three systems analyses, and to increase insight into the similarities and differences in the policy processes of these European country cases. A systems analysis of the local HEPA policymaking process was performed in three European countries involved in the 'REsearch into POlicy to enhance Physical Activity' (REPOPA) project, resulting in three schematic models showing the main stakeholders and their relationships. The models were used to compare the systems, focusing on implications with respect to collaboration and use of evidence in local HEPA policymaking. Policy documents and relevant webpages were examined and main stakeholders were interviewed. The systems analysis in each country identified the main stakeholders involved and their position and relations in the policymaking process. The Netherlands and Denmark were the most similar and both differed most from Romania, especially at the level of accountability of the local public authorities for local HEPA policymaking. The categories of driving forces underlying the relations between stakeholders were formal relations, informal interaction and knowledge exchange. A systems analysis providing detailed descriptions of positions and relations in the stakeholder network in local level HEPA policymaking is rather unique in this area. The analyses are useful when a need arises for increased interaction, collaboration and use of knowledge between stakeholders in the local HEPA network, as they provide an overview of the stakeholders involved and their mutual relations. This information can be an important starting point to enhance the uptake of evidence and build more effective public health policies.

Evaluation of organic anion-transporting polypeptide 1B1 and CYP3A4 activities in primary human hepatocytes and HepaRG cells cultured in a dynamic three-dimensional bioreactor system.

PubMed

Ulvestad, Maria; Darnell, Malin; Molden, Espen; Ellis, Ewa; Åsberg, Anders; Andersson, Tommy B

2012-10-01

The long-term stability of liver cell functions is a major challenge when studying hepatic drug transport, metabolism, and toxicity in vitro. The aim of the present study was to investigate organic anion-transporting polypeptide (OATP) 1B1 and CYP3A4 activities in fresh primary human hepatocytes and differentiated cryopreserved HepaRG cells when cultured in a three-dimensional (3D) bioreactor system. OATP1B1 activity was determined by loss from media experiments of [(3)H]estradiol-17β-D-glucuronide and atorvastatin acid (ATA) for up to 7 days in culture. ATA metabolite formation was determined at days 3 to 4 to evaluate CYP3A4 activity. Overall, the results showed that freshly isolated human hepatocytes inoculated in the bioreactor retained OATP1B1 activity for at least 7 days, whereas in HepaRG cells no OATP1B1 activity was observed beyond day 2. The activity data were in agreement with immunohistochemical stainings, which showed that OATP1B1 protein expression was preserved for at least 9 days in fresh human hepatocytes, whereas OATP1B1 was expressed markedly lower in HepaRG cells after 9 days in culture. Fresh human hepatocytes and HepaRG cells exhibited similar CYP3A4 activity in bioreactor culture, and immunohistochemical stainings supported these findings. Activity and mRNA expression of OATP1B1 and CYP3A4 in primary human hepatocytes compared with HepaRG cells in fresh suspensions were in agreement with data obtained in bioreactor culture. In conclusion, freshly isolated human hepatocytes cultured in a 3D bioreactor system preserve both OATP1B1 and CYP3A4 activities, allowing long-term in vitro studies on drug disposition and toxicity.

HBV Bypasses the Innate Immune Response and Does Not Protect HCV From Antiviral Activity of Interferon.

PubMed

Mutz, Pascal; Metz, Philippe; Lempp, Florian A; Bender, Silke; Qu, Bingqian; Schöneweis, Katrin; Seitz, Stefan; Tu, Thomas; Restuccia, Agnese; Frankish, Jamie; Dächert, Christopher; Schusser, Benjamin; Koschny, Ronald; Polychronidis, Georgios; Schemmer, Peter; Hoffmann, Katrin; Baumert, Thomas F; Binder, Marco; Urban, Stephan; Bartenschlager, Ralf

2018-05-01

Hepatitis C virus (HCV) infection is sensitive to interferon (IFN)-based therapy, whereas hepatitis B virus (HBV) infection is not. It is unclear whether HBV escapes detection by the IFN-mediated immune response or actively suppresses it. Moreover, little is known on how HBV and HCV influence each other in coinfected cells. We investigated interactions between HBV and the IFN-mediated immune response using HepaRG cells and primary human hepatocytes (PHHs). We analyzed the effects of HBV on HCV replication, and vice versa, at the single-cell level. PHHs were isolated from liver resection tissues from HBV-, HCV-, and human immunodeficiency virus-negative patients. Differentiated HepaRG cells overexpressing the HBV receptor sodium taurocholate cotransporting polypeptide (dHepaRGNTCP) and PHHs were infected with HBV. Huh7.5 cells were transfected with circular HBV DNA genomes resembling viral covalently closed circular DNA (cccDNA), and subsequently infected with HCV; this served as a model of HBV and HCV coinfection. Cells were incubated with IFN inducers, or IFNs, and antiviral response and viral replication were analyzed by immune fluorescence, reverse-transcription quantitative polymerase chain reaction, enzyme-linked immunosorbent assays, and flow cytometry. HBV infection of dHepaRGNTCP cells and PHHs neither activated nor inhibited signaling via pattern recognition receptors. Incubation of dHepaRGNTCP cells and PHHs with IFN had little effect on HBV replication or levels of cccDNA. HBV infection of these cells did not inhibit JAK-STAT signaling or up-regulation of IFN-stimulated genes. In coinfected cells, HBV did not prevent IFN-induced suppression of HCV replication. In dHepaRGNTCP cells and PHHs, HBV evades the induction of IFN and IFN-induced antiviral effects. HBV infection does not rescue HCV from the IFN-mediated response. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

Evaluating the Long-Term Health and Economic Impacts of Central Residential Air Filtration for Reducing Premature Mortality Associated with Indoor Fine Particulate Matter (PM2.5) of Outdoor Origin

PubMed Central

Zhao, Dan; Azimi, Parham; Stephens, Brent

2015-01-01

Much of human exposure to fine particulate matter (PM2.5) of outdoor origin occurs in residences. High-efficiency particle air filtration in central heating, ventilating, and air-conditioning (HVAC) systems is increasingly being used to reduce concentrations of particulate matter inside homes. However, questions remain about the effectiveness of filtration for reducing exposures to PM2.5 of outdoor origin and adverse health outcomes. Here we integrate epidemiology functions and mass balance modeling to estimate the long-term health and economic impacts of HVAC filtration for reducing premature mortality associated with indoor PM2.5 of outdoor origin in residences. We evaluate 11 classifications of filters (MERV 5 through HEPA) using six case studies of single-family home vintages and ventilation system combinations located in 22 U.S. cities. We estimate that widespread use of higher efficiency filters would reduce premature mortality by 0.002–2.5% and increase life expectancy by 0.02–1.6 months, yielding annual monetary benefits ranging from $1 to $1348 per person in the homes and locations modeled herein. Large differences in the magnitude of health and economic impacts are driven largely by differences in rated filter efficiency and building and ventilation system characteristics that govern particle infiltration and persistence, with smaller influences attributable to geographic location. PMID:26197328

Evaluating the Long-Term Health and Economic Impacts of Central Residential Air Filtration for Reducing Premature Mortality Associated with Indoor Fine Particulate Matter (PM2.5) of Outdoor Origin.

PubMed

Zhao, Dan; Azimi, Parham; Stephens, Brent

2015-07-21

Much of human exposure to fine particulate matter (PM2.5) of outdoor origin occurs in residences. High-efficiency particle air filtration in central heating, ventilating, and air-conditioning (HVAC) systems is increasingly being used to reduce concentrations of particulate matter inside homes. However, questions remain about the effectiveness of filtration for reducing exposures to PM2.5 of outdoor origin and adverse health outcomes. Here we integrate epidemiology functions and mass balance modeling to estimate the long-term health and economic impacts of HVAC filtration for reducing premature mortality associated with indoor PM2.5 of outdoor origin in residences. We evaluate 11 classifications of filters (MERV 5 through HEPA) using six case studies of single-family home vintages and ventilation system combinations located in 22 U.S. cities. We estimate that widespread use of higher efficiency filters would reduce premature mortality by 0.002-2.5% and increase life expectancy by 0.02-1.6 months, yielding annual monetary benefits ranging from $1 to $1348 per person in the homes and locations modeled herein. Large differences in the magnitude of health and economic impacts are driven largely by differences in rated filter efficiency and building and ventilation system characteristics that govern particle infiltration and persistence, with smaller influences attributable to geographic location.

Health-enhancing physical activity and health-related risk in a sample of north Mexican, office-based employees.

PubMed

Gilson, Nicholas David

2007-01-01

Levels of hypertension, obesity and raised total cholesterol are increasing in Mexico. Mexicans employed within sedentary occupations may be particularly at risk of developing one, or a clustering of these health-related risk factors, due to lack of participation in health enhancing physical activity (HEPA). The purpose of this study is to examine: (a) prevalence rates of hypertension, obesity and raised total cholesterol, and (b) the link between these variables and HEPA, in a sample of North Mexican, office-based employees. Methods include an assessment of systolic/diastolic blood pressure, % body fat, total cholesterol and HEPA (7-day self-report) in 47 men (33 +/- 10 years) and 43 women (28 +/- 7 years) from Monterrey, a large industrial city in the Northeast of Mexico. Values were compared against recognised health-related thresholds to determine prevalence rates of individual health-related risk factors, along with clustering of two or more risk factors. Relationships between variables were analysed using Pearson product moment correlation. The results show Men had a high prevalence of obesity (32%) and raised total cholesterol (44%), while women's rates were lower (7% and 10% respectively). More men (59%) than women (17%) demonstrated a clustering of two or more risk factors. HEPA participation was low in both men (9%) and women (16%). A significant relationship was found between men's HEPA and % body fat (r = -0.31; p < 0.05). The high levels of inactivity found in both men and women were cause for concern, suggesting the need for innovative intervention approaches, which aim to integrate physical activity into busy working lives.

Protective effects of an ethanol extract of Angelica keiskei against acetaminophen-induced hepatotoxicity in HepG2 and HepaRG cells

PubMed Central

Choi, Yoon-Hee; Lee, Hyun Sook; Chung, Cha-Kwon

2017-01-01

BACKGROUND/OBJECTIVE Although Angelica keiskei (AK) has widely been utilized for the purpose of general health improvement among Asian, its functionality and mechanism of action. The aim of this study was to determine the protective effect of ethanol extract of AK (AK-Ex) on acute hepatotoxicity induced by acetaminophen (AAP) in HepG2 human hepatocellular liver carcinoma cells and HepaRG human hepatic progenitor cells. MATERIALS/METHODS AK-Ex was prepared HepG2 and HepaRG cells were cultured with various concentrations and 30 mM AAP. The protective effects of AK-Ex against AAP-induced hepatotoxicity in HepG2 and HepaRG cells were evaluated using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide, lactate dehydrogenase (LDH) assay, flow cytometry, and Western blotting. RESULTS AK-Ex, when administered prior to AAP, increased cell growth and decreased leakage of LDH in a dose-dependent manner in HepG2 and HepaRG cells against AAP-induced hepatotoxicity. AK-Ex increased the level of Bcl-2 and decreased the levels of Bax, Bok and Bik decreased the permeability of the mitochondrial membrane in HepG2 cells intoxicated with AAP. AK-Ex decreased the cleavage of poly (ADP-ribose) polymerase (PARP) and the activation of caspase-9, -7, and -3. CONCLUSIONS These results demonstrate that AK-Ex downregulates apoptosis via intrinsic and extrinsic pathways against AAP-induced hepatotoxicity. We suggest that AK could be a useful preventive agent against AAP-induced apoptosis in hepatocytes. PMID:28386382

Testing the performance of microbiological safety cabinets used in microbiology laboratories in South Korea.

PubMed

Hwang, S H; Yi, T W; Cho, K H; Lee, I M; Yoon, C S

2011-09-01

To test a performance of the microbiological safety cabinets (MSCs) according to the type of MSCs in microbial laboratories. Tests were carried out to assess the performance of 31 MSCs in 14 different facilities, including six different biological test laboratories in six hospitals and eight different laboratories in three universities. The following tests were performed on the MSCs: the downflow test, intake velocity test, high-efficiency particulate air filter leak test and the airflow smoke pattern test. These performance tests were carried out in accordance with the standard procedures. Only 23% of Class II A1 (8), A2 (19) and unknown MSCs (4) passed these performance tests. The main reasons for the failure of MSCs were inappropriate intake velocity (65%), leakage in the HEPA filter sealing (50%), unbalanced airflow smoke pattern in the cabinets (39%) and inappropriate downflow (27%). This study showed that routine checks of MSCs are important to detect and strengthen the weak spots that frequently develop, as observed during the evaluation of the MSCs of various institutions. Routine evaluation and maintenance of MSCs are critical for optimizing performance. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

Effectiveness and cost of reducing particle-related mortality with particle filtration

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

Fisk, W. J.; Chan, W. R.

This study evaluates the mortality-related benefits and costs of improvements in particle filtration in U.S. homes and commercial buildings based on models with empirical inputs. The models account for time spent in various environments as well as activity levels and associated breathing rates. The scenarios evaluated include improvements in filter efficiencies in both forced-air heating and cooling systems of homes and heating, ventilating, and air conditioning systems of workplaces as well as use of portable air cleaners in homes. The predicted reductions in mortality range from approximately 0.25 to 2.4 per 10 000 population. The largest reductions in mortality were frommore » interventions with continuously operating portable air cleaners in homes because, given our scenarios, these portable air cleaners with HEPA filters most reduced particle exposures. For some interventions, predicted annual mortality-related economic benefits exceed $1000 per person. Economic benefits always exceed costs with benefit-to-cost ratios ranging from approximately 3.9 to 133. In conclusion, restricting interventions to homes of the elderly further increases the mortality reductions per unit population and the benefit-to-cost ratios.« less

Comparison of aryl hydrocarbon hydroxylase and acetanilide 4-hydroxylase induction by polycyclic aromatic compounds in human and mouse cell lines.

PubMed

Jaiswal, A K; Nebert, D W; Eisen, H W

1985-08-01

The human MCF-7 and the mouse Hepa-1 cell culture lines were compared for aryl hydrocarbon hydroxylase and acetanilide 4-hydroxylase inducibility by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and benzo[a]anthracene (BA) and TCDD- and BA-specific binding in the cytosol and nucleus. The effective concentration of BA in the growth medium required to induce either enzyme to 50% of its maximally inducible activity (EC50) was the same (5-11 microM) in both MCF-7 and Hepa-1 cells. On the other hand, the EC50 for TCDD in MCF-7 cells (5-25 nM) was more than 40-fold greater than that in Hepa-1 cells (0.4 to 0.6 nM). P1-450- and P3-450-specific mouse cDNA probes were used to quantitate mRNA induction in the Hepa-1 cell line. P1-450 mRNA was induced markedly by TCDD and benzo[a] anthracene, whereas P3-450 mRNA was induced negligibly. A P1-450-specific human cDNA probe was used to quantitate P1-450 mRNA induction in the MCF-7 cell line. Aryl hydrocarbon hydroxylase inducibility by TCDD or BA always paralleled P1-450 mRNA inducibility in either the mouse or human line. Although the cytosolic Ah receptor in Hepa-1 cells was easily detected by sucrose density gradient centrifugation, gel permeation chromatography, and anion-exchange high-performance liquid chromatography, the cytosolic receptor cannot be detected in MCF-7 cells. Following in vivo exposure of cultures to radiolabeled TCDD, the intranuclear concentration of inducer-receptor complex was at least fifty times greater in Hepa-1 than MCF-7 cultures. The complete lack of measurable cytosolic receptor and almost totally absent inducer-receptor complex in the nucleus of MCF-7 cells was, therefore, out of proportion to its capacity for aryl hydrocarbon hydroxylase and acetanilide 4-hydroxylase inducibility. This MCF-7 line should provide an interesting model for a better understanding of the mechanisms of drug-metabolizing enzyme induction by polycyclic aromatic compounds, including the Ah receptor-mediated mechanism.

A practice-changing culture method relying on shaking substantially increases mitochondrial energy metabolism and functionality of human liver cell lines.

PubMed

Adam, Aziza A A; van der Mark, Vincent A; Donkers, Joanne M; Wildenberg, Manon E; Oude Elferink, Ronald P J; Chamuleau, Robert A F M; Hoekstra, Ruurdtje

2018-01-01

Practice-changing culturing techniques of hepatocytes are highly required to increase their differentiation. Previously, we found that human liver cell lines HepaRG and C3A acquire higher functionality and increased mitochondrial biogenesis when cultured in the AMC-Bioartificial liver (BAL). Dynamic medium flow (DMF) is one of the major contributors to this stimulatory effect. Recently, we found that DMF-culturing by shaking of HepaRG monolayers resulted in higher mitochondrial biogenesis. Here we further investigated the effect of DMF-culturing on energy metabolism and hepatic functionality of HepaRG and C3A monolayers. HepaRG and C3A DMF-monolayers were incubated with orbital shaking at 60 rpm during the differentiation phase, while control monolayers were maintained statically. Subsequently, energy metabolism and hepatic functionality were compared between static and DMF-cultures. DMF-culturing of HepaRG cells substantially increased hepatic differentiation; transcript levels of hepatic structural genes and hepatic transcription regulators were increased up to 15-fold (Cytochrome P450 3A4) and nuclear translocation of hepatic transcription factor CEBPα was stimulated. Accordingly, hepatic functions were positively affected, including ammonia elimination, urea production, bile acid production, and CYP3A4 activity. DMF-culturing shifted energy metabolism from aerobic glycolysis towards oxidative phosphorylation, as indicated by a decline in lactate production and glucose consumption, and an increase in oxygen consumption. Similarly, DMF-culturing increased mitochondrial energy metabolism and hepatic functionality of C3A cells. In conclusion, simple shaking of monolayer cultures substantially improves mitochondrial energy metabolism and hepatic differentiation of human liver cell lines. This practice-changing culture method may prove to prolong the in-vitro maintenance of primary hepatocytes and increase hepatic differentiation of stem cells.

"A gift from heaven" or "This was not for me". A mixed methods approach to describe experiences of participation in an outsourced physical activity program for persons with rheumatoid arthritis.

PubMed

Demmelmaier, Ingrid; Lindkvist, Åsa; Nordgren, Birgitta; Opava, Christina H

2015-03-01

Most persons with rheumatoid arthritis (RA) do not perform health-enhancing physical activity (HEPA). Evaluations of innovative HEPA programs need to be complemented with descriptive and qualitative data from the users. The aim of this mixed methods study was to explore and describe how a subgroup of the RA population perceives participation during the first year of an outsourced 2-year HEPA program. Data were collected by a study-specific postal survey to 220 program participants (response rate 87%, n = 191) and by interviews with a purposefully selected subsample of 35, including completers and dropouts. The survey data were analyzed by descriptive statistics and the interviews by qualitative content analysis.The survey demonstrated increased self-reported physical activity in 165 participants (86%). After the first year of the program, participants reported having performed "regular" or "periodical" circuit training (78%) and physical activity in daily life (92%). The most valued program components were circuit training and physical activity in daily life, both rated median 5/5. Coach support, prompts by text messages, and expert lectures were rated median 4/5. Five categories emerged from the interviews describing expectations, facilitators, gains, maintenance, and obstacles/suggestions for improvement of the program. The results demonstrate that HEPA outside health care is highly appreciated by a subgroup of the RA population. Professional coaching and prompts by text messages seem to be particularly useful facilitators. Individual preferences emphasize the need to tailor settings, exercise formats, and behavioral support for HEPA even in a narrow, self-selected group with RA.

Reliability and Validity of the SE-HEPA: Examining Physical Activity- and Healthy Eating-Specific Self-Efficacy among a Sample of Preadolescents

ERIC Educational Resources Information Center

Steele, Michael M.; Burns, Leonard G.; Whitaker, Brandi N.

2013-01-01

Objective. The purpose of this study was to examine the psychometric properties of the self-efficacy for healthy eating and physical activity measure (SE-HEPA) for preadolescents. Method. The reliability of the measure was examined to determine if the internal consistency of the measure was adequate (i.e., [alpha]s greater than 0.70). Next, in an…

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

Nichols, Ralph L.; Seitz, Roger R.; Dixon, Kenneth L.

The Waste Treatment and Immobilization Plant (WTP) at Hanford is being constructed to treat 56 million gallons of radioactive waste currently stored in underground tanks at the Hanford site. Operation of the WTP will generate several solid secondary waste (SSW) streams including used process equipment, contaminated tools and instruments, decontamination wastes, high-efficiency particulate air filters (HEPA), carbon adsorption beds, silver mordenite iodine sorbent beds, and spent ion exchange resins (IXr) all of which are to be disposed in the Integrated Disposal Facility (IDF). An applied research and development program was developed using a phased approach to incrementally develop the informationmore » necessary to support the IDF PA with each phase of the testing building on results from the previous set of tests and considering new information from the IDF PA calculations. This report contains the results from the exploratory phase, Phase 1 and preliminary results from Phase 2. Phase 3 is expected to begin in the fourth quarter of FY17.« less

The Influence of Microbiology on Spacecraft Design and Controls: A Historical Perspective of the Shuttle and International Space Station Programs

NASA Technical Reports Server (NTRS)

Castro, Victoria A.; Bruce, Rebekah J.; Ott, C. Mark; Pierson, D. L.

2006-01-01

For over 40 years, NASA has been putting humans safely into space in part by minimizing microbial risks to crew members. Success of the program to minimize such risks has resulted from a combination of engineering and design controls as well as active monitoring of the crew, food, water, hardware, and spacecraft interior. The evolution of engineering and design controls is exemplified by the implementation of HEPA filters for air treatment, antimicrobial surface materials, and the disinfection regimen currently used on board the International Space Station. Data from spaceflight missions confirm the effectiveness of current measures; however, fluctuations in microbial concentrations and trends in contamination events suggest the need for continued diligence in monitoring and evaluation as well as further improvements in engineering systems. The knowledge of microbial controls and monitoring from assessments of past missions will be critical in driving the design of future spacecraft.

Seismic analyses of equipment in 2736-Z complex. Revision 1

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

Ocoma, E.C.

1995-04-01

This report documents the structural qualification for the existing equipment when subjected to seismic loading in the Plutonium Storage Complex. It replaces in entirety Revision 0 and reconciles the U.S. Department of Energy (DOE) comments on Revision 0. The Complex consists of 2736-Z Building (plutonium storage vault), 2736-ZA Building (vault ventilation equipment building), and 2736-ZB Building (shipping/receiving, repackaging activities). The existing equipment structurally qualified in this report are the metal storage racks for 7 inch and lard cans in room 2 of Building 2736-Z; the cubicles, can holders and pedestals in rooms 1, 3, and 4 of Building 2736-Z; themore » ventilation duct including exhaust fans/motors, emergency diesel generator, and HEPA filter housing in Building 2736-ZA; the repackaging glovebox in Building 2736-ZB; and the interface duct between Buildings 2736-Z and 2736-ZA.« less

Development of Test Protocols for International Space Station Particulate Filters

NASA Technical Reports Server (NTRS)

Vijayakumar, R.; Green, Robert D.; Agui, Juan H.

2015-01-01

Air quality control on the International Space Station (ISS) is a vital requirement for maintaining a clean environment for the crew and the hardware. This becomes a serious challenge in pressurized space compartments since no outside air ventilation is possible, and a larger particulate load is imposed on the filtration system due to lack of gravitational settling. The ISS Environmental Control and Life Support System (ECLSS) uses a filtration system that has been in use for over 14 years and has proven to meet this challenge. The heart of this system is a traditional High-Efficiency Particulate Air (HEPA) filter configured to interface with the rest of the life support elements and provide effective cabin filtration. The filter element for this system has a non-standard cross-section with a length-to-width ratio (LW) of 6.6. A filter test setup was designed and built to meet industry testing standards. A CFD analysis was performed to initially determine the optimal duct geometry and flow configuration. Both a screen and flow straighter were added to the test duct design to improve flow uniformity and face velocity profiles were subsequently measured to confirm. Flow quality and aerosol mixing assessments show that the duct flow is satisfactory for the intended leak testing. Preliminary leak testing was performed on two different ISS filters, one with known perforations and one with limited use, and results confirmed that the testing methods and photometer instrument are sensitive enough to detect and locate compromised sections of an ISS BFE.Given the engineering constraints in designing spacecraft life support systems, it is anticipated that non-industry standard filters will be required in future designs. This work is focused on developing test protocols for testing the ISS BFE filters, but the methodology is general enough to be extended to other present and future spacecraft filters. These techniques for characterizing the test duct and perform leak testing can be applied to conducting acceptance testing and inventory testing for future manned exploration programs with air revitalization filtration needs, possibly even for in-situ filter element integrity testing for extensively long-duration missions. We plan to address the unique needs for test protocols for crewed spacecraft particulate filters by preparing the initial version of a standard, to be documented as a NASA Technical Memorandum (TM).

Comparison of Liver Cell Models Using the Basel Phenotyping Cocktail.

PubMed

Berger, Benjamin; Donzelli, Massimiliano; Maseneni, Swarna; Boess, Franziska; Roth, Adrian; Krähenbühl, Stephan; Haschke, Manuel

2016-01-01

Currently used hepatocyte cell systems for in vitro assessment of drug metabolism include hepatoma cell lines and primary human hepatocyte (PHH) cultures. We investigated the suitability of the validated in vivo Basel phenotyping cocktail (caffeine [CYP1A2], efavirenz [CYP2B6], losartan [CYP2C9], omeprazole [CYP2C19], metoprolol [CYP2D6], midazolam [CYP3A4]) in vitro and characterized four hepatocyte cell systems (HepG2 cells, HepaRG cells, and primary cryopreserved human hepatocytes in 2-dimensional [2D] culture or in 3D-spheroid co-culture) regarding basal metabolism and CYP inducibility. Under non-induced conditions, all CYP activities could be determined in 3D-PHH, CYP2B6, CYP2C19, CYP2D6, and CYP3A4 in 2D-PHH and HepaRG, and CYP2C19 and CYP3A4 in HepG2 cells. The highest non-induced CYP activities were observed in 3D-PHH and HepaRG cells. mRNA expression was at least four-fold higher for all CYPs in 3D-PHH compared to the other cell systems. After treatment with 20 μM rifampicin, mRNA increased 3- to 50-fold for all CYPs except CYP1A2 and 2D6 for HepaRG and 3D-PHH, 4-fold (CYP2B6) and 17-fold (CYP3A4) for 2D-PHH and four-fold (CYP3A4) for HepG2. In 3D-PHH at least a two-fold increase in CYP activity was observed for all inducible CYP isoforms while CYP1A2 and CYP2C9 activity did not increase in 2D-PHH and HepaRG. CYP inducibility assessed in vivo using the same phenotyping probes was also best reflected by the 3D-PHH model. Our studies show that 3D-PHH and (with some limitations) HepaRG are suitable cell systems for assessing drug metabolism and CYP induction in vitro . HepG2 cells are less suited to assess CYP induction of the 2C and 3A family. The Basel phenotyping cocktail is suitable for the assessment of CYP activity and induction also in vitro .

A cellular model to study drug-induced liver injury in nonalcoholic fatty liver disease: Application to acetaminophen

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

Michaut, Anaïs; Le Guillou, Dounia; Moreau, Caroline

Obesity and nonalcoholic fatty liver disease (NAFLD) can increase susceptibility to hepatotoxicity induced by some xenobiotics including drugs, but the involved mechanisms are poorly understood. For acetaminophen (APAP), a role of hepatic cytochrome P450 2E1 (CYP2E1) is suspected since the activity of this enzyme is consistently enhanced during NAFLD. The first aim of our study was to set up a cellular model of NAFLD characterized not only by triglyceride accumulation but also by higher CYP2E1 activity. To this end, human HepaRG cells were incubated for one week with stearic acid or oleic acid, in the presence of different concentrations ofmore » insulin. Although cellular triglycerides and the expression of lipid-responsive genes were similar with both fatty acids, CYP2E1 activity was significantly increased only by stearic acid. CYP2E1 activity was reduced by insulin and this effect was reproduced in cultured primary human hepatocytes. Next, APAP cytotoxicity was assessed in HepaRG cells with or without lipid accretion and CYP2E1 induction. Experiments with a large range of APAP concentrations showed that the loss of ATP and glutathione was almost always greater in the presence of stearic acid. In cells pretreated with the CYP2E1 inhibitor chlormethiazole, recovery of ATP was significantly higher in the presence of stearate with low (2.5 mM) or high (20 mM) concentrations of APAP. Levels of APAP-glucuronide were significantly enhanced by insulin. Hence, HepaRG cells can be used as a valuable model of NAFLD to unveil important metabolic and hormonal factors which can increase susceptibility to drug-induced hepatotoxicity. - Highlights: • Nonalcoholic fatty liver disease (NAFLD) is frequent in obese individuals. • NAFLD can favor hepatotoxicity induced by some drugs including acetaminophen (APAP). • A model of NAFLD was set up by using HepaRG cells incubated with stearate or oleate. • Stearate-loaded HepaRG cells presented higher cytochrome P450 2E1 (CYP2E1) activity. • APAP cytotoxicity was stronger in steatotic HepaRG cells with higher CYP2E1 activity.« less

Comparison of Liver Cell Models Using the Basel Phenotyping Cocktail

PubMed Central

Berger, Benjamin; Donzelli, Massimiliano; Maseneni, Swarna; Boess, Franziska; Roth, Adrian; Krähenbühl, Stephan; Haschke, Manuel

2016-01-01

Currently used hepatocyte cell systems for in vitro assessment of drug metabolism include hepatoma cell lines and primary human hepatocyte (PHH) cultures. We investigated the suitability of the validated in vivo Basel phenotyping cocktail (caffeine [CYP1A2], efavirenz [CYP2B6], losartan [CYP2C9], omeprazole [CYP2C19], metoprolol [CYP2D6], midazolam [CYP3A4]) in vitro and characterized four hepatocyte cell systems (HepG2 cells, HepaRG cells, and primary cryopreserved human hepatocytes in 2-dimensional [2D] culture or in 3D-spheroid co-culture) regarding basal metabolism and CYP inducibility. Under non-induced conditions, all CYP activities could be determined in 3D-PHH, CYP2B6, CYP2C19, CYP2D6, and CYP3A4 in 2D-PHH and HepaRG, and CYP2C19 and CYP3A4 in HepG2 cells. The highest non-induced CYP activities were observed in 3D-PHH and HepaRG cells. mRNA expression was at least four-fold higher for all CYPs in 3D-PHH compared to the other cell systems. After treatment with 20 μM rifampicin, mRNA increased 3- to 50-fold for all CYPs except CYP1A2 and 2D6 for HepaRG and 3D-PHH, 4-fold (CYP2B6) and 17-fold (CYP3A4) for 2D-PHH and four-fold (CYP3A4) for HepG2. In 3D-PHH at least a two-fold increase in CYP activity was observed for all inducible CYP isoforms while CYP1A2 and CYP2C9 activity did not increase in 2D-PHH and HepaRG. CYP inducibility assessed in vivo using the same phenotyping probes was also best reflected by the 3D-PHH model. Our studies show that 3D-PHH and (with some limitations) HepaRG are suitable cell systems for assessing drug metabolism and CYP induction in vitro. HepG2 cells are less suited to assess CYP induction of the 2C and 3A family. The Basel phenotyping cocktail is suitable for the assessment of CYP activity and induction also in vitro. PMID:27917125

Growth-inhibitory effects of the red alga Gelidium amansii on cultured cells.

PubMed

Chen, Yue-Hwa; Tu, Ching-Jung; Wu, Hsiao-Ting

2004-02-01

The objective of this study was to investigate the effects of Gelidium amansii, an edible red agar cultivated off the northeast coast of Taiwan, on the growth of two lines of cancer cells, murine hepatoma (Hepa-1) and human leukemia (HL-60) cells, as well as a normal cell line, murine embryo fibroblast cells (NIH-3T3). The potential role of G. amansii on the induction of apoptosis was also examined. The results indicated that all extracts from G. amansii, including phosphate-buffered saline (PBS) and methanol extracts from dried algae as well as the dimethyl sulfoxide (DMSO) extract from freeze-dried G. amansii agar, inhibited the growth of Hepa-1 and NIH-3T3 cells, but not the growth of HL-60 cells. Annexin V-positive cells were observed in methanol and DMSO extract-treated, but not PBS extract-treated Hepa-1 and NIH-3T3 cells, suggesting that the lipid-soluble extracts of G. amansii induced apoptosis. In summary, extracts of G. amansii from various preparations exhibited antiproliferative effects on Hepa-1 and NIH-3T3 cells, and apoptosis may play a role in the methanol and DMSO extract-induced inhibitory effects. However, the antiproliferative effects of PBS extracts was not through apoptosis. Moreover, the growth-inhibitory effects of G. amansii were not specific to cancer cells.

Metronidazole reduces the expression of cytochrome P450 enzymes in HepaRG cells and cryopreserved human hepatocytes.

PubMed

Kudo, Toshiyuki; Endo, Yumiko; Taguchi, Rina; Yatsu, Masami; Ito, Kiyomi

2015-05-01

1. Blood levels of S-warfarin have been reported to be increased by concomitant administration of metronidazole (MTZ), an antiprotozoal imidazole derivative. 2. To elucidate the mechanism of this interaction and to identify other possible drug-drug interactions, we conducted an in vitro study with the human hepatoma HepaRG cells and cryopreserved human hepatocytes on the ability of MTZ to reduce the expression of cytochrome P450 (CYP) as well as nuclear receptors that regulate the expression of these enzymes. 3. HepaRG cells and cryopreserved human hepatocytes were treated with MTZ (20 to 500 µM) and were then analyzed by real-time RT-PCR to determine mRNA levels of drug-metabolizing enzymes and nuclear receptors. 4. In both cells, the expressions of CYP2C8, CYP2C9, CYP3A4 and constitutive androstane receptor (CAR) were decreased by MTZ treatment. Particularly, in HepaRG cells, their mRNA levels were decreased by MTZ treatment in a concentration-dependent manner. 5. Our findings suggest that the interaction between MTZ and S-warfarin may be due to the MTZ-induced down-regulation of CYP2C9, the primary enzyme responsible for S-warfarin hydroxylation, and CAR, which regulates CYP2C9 expression. We also found that MTZ use may alter the disposition of drugs metabolized by the CYP isozymes investigated.

Proteomic analysis of plasma membranes isolated from undifferentiated and differentiated HepaRG cells

PubMed Central

2012-01-01

Liver infection with hepatitis B virus (HBV), a DNA virus of the Hepadnaviridae family, leads to severe disease, such as fibrosis, cirrhosis and hepatocellular carcinoma. The early steps of the viral life cycle are largely obscure and the host cell plasma membrane receptors are not known. HepaRG is the only proliferating cell line supporting HBV infection in vitro, following specific differentiation, allowing for investigation of new host host-cell factors involved in viral entry, within a more robust and reproducible environment. Viral infection generally begins with receptor recognition at the host cell surface, following highly specific cell-virus interactions. Most of these interactions are expected to take place at the plasma membrane of the HepaRG cells. In the present study, we used this cell line to explore changes between the plasma membrane of undifferentiated (−) and differentiated (+) cells and to identify differentially-regulated proteins or signaling networks that might potentially be involved in HBV entry. Our initial study identified a series of proteins that are differentially expressed in the plasma membrane of (−) and (+) cells and are good candidates for potential cell-virus interactions. To our knowledge, this is the first study using functional proteomics to study plasma membrane proteins from HepaRG cells, providing a platform for future experiments that will allow us to understand the cell-virus interaction and mechanism of HBV viral infection. PMID:22857383

Refinements of environmental assessment during an outbreak investigation of invasive aspergillosis in a leukemia and bone marrow transplant unit.

PubMed

Thio, C L; Smith, D; Merz, W G; Streifel, A J; Bova, G; Gay, L; Miller, C B; Perl, T M

2000-01-01

To investigate an outbreak of aspergillosis in a leukemia and bone marrow transplant (BMT) unit and to improve environmental assessment strategies to detect Aspergillus. Epidemiological investigation and detailed environmental assessment. A tertiary-care university hospital with a 37-bed leukemia and BMT unit Leukemic or BMT patients with invasive aspergillosis identified through prospective surveillance and confirmed by chart review. We verified the diagnosis of invasive fungal infection by reviewing medical charts of at-risk patients, performing a case-control study to determine risk factors for infection, instituting wet mopping to clean all floors, providing N95 masks to protect patients outside high-efficiency particulate air (HEPA)-filtered areas, altering traffic patterns into the unit, and performing molecular typing of selected Aspergillus flavus isolates. To assess the environment, we verified pressure relationships between the rooms and hallway and between buildings, and we compared the ability of large-volume (1,200 L) and small-volume (160 L) air samplers to detect Aspergillus spores. Of 29 potential invasive aspergillosis cases, 21 were confirmed by medical chart review. Risk factors for developing invasive aspergillosis included the length of time since malignancy was diagnosed (odds ratio [OR], 1.0; P=.05) and hospitalization in a patient room located near a stairwell door (OR, 3.7; P=.05). Two of five A. flavus patient isolates were identical to one of the environmental isolates. The pressure in most of the rooms was higher than in the corridors, but the pressure in the oncology unit was negative with respect to the physically adjacent hospital; consequently, the unit acted essentially as a vacuum that siphoned non-HEPA-filtered air from the main hospital. Of the 78 samples obtained with a small-volume air sampler, none grew an Aspergillus species, whereas 10 of 40 cultures obtained with a large-volume air sampler did. During active construction, Aspergillus spores may have entered the oncology unit from the physically adjacent hospital because the air pressure differed. Guidelines that establish the minimum acceptable pressures and specify which pressure relationships to test in healthcare settings are needed. Our data show that large-volume air samples are superior to small-volume samples to assess for Aspergillus in the healthcare environment.

Incomplete lung recovery following sub-acute inhalation of combustion-derived ultrafine particles in mice.

PubMed

Noël, A; Xiao, R; Perveen, Z; Zaman, H M; Rouse, R L; Paulsen, D B; Penn, A L

2016-02-24

Particulate matter (PM) is one of the six criteria pollutant classes for which National Ambient Air Quality Standards have been set by the United States Environmental Protection Agency. Exposures to PM have been correlated with increased cardio-pulmonary morbidity and mortality. Butadiene soot (BDS), generated from the incomplete combustion of 1,3-butadiene (BD), is both a model PM mixture and a real-life example of a petrochemical product of incomplete combustion. There are numerous events, including wildfires, accidents at refineries and tank car explosions that result in sub-acute exposure to high levels of airborne particles, with the people exposed facing serious health problems. These real-life events highlight the need to investigate the health effects induced by short-term exposure to elevated levels of PM, as well as to assess whether, and if so, how well these adverse effects are resolved over time. In the present study, we investigated the extent of recovery of mouse lungs 10 days after inhalation exposures to environmentally-relevant levels of BDS aerosols had ended. Female BALB/c mice exposed to either HEPA-filtered air or to BDS (5 mg/m(3) in HEPA filtered air, 4 h/day, 21 consecutive days) were sacrificed immediately, or 10 days after the final BDS exposure. Bronchoalveolar lavage fluid (BALF) was collected for cytology and cytokine analysis. Lung proteins and RNA were extracted for protein and gene expression analysis. Lung histopathology evaluation also was performed. Sub-acute exposures of mice to hydrocarbon-rich ultrafine particles induced: (1) BALF neutrophil elevation; (2) lung mucosal inflammation, and (3) increased BALF IL-1β concentration; with all three outcomes returning to baseline levels 10 days post-exposure. In contrast, (4) lung connective tissue inflammation persisted 10 days post-exposure; (5) we detected time-dependent up-regulation of biotransformation and oxidative stress genes, with incomplete return to baseline levels; and (6) we observed persistent particle alveolar load following 10 days of recovery. These data show that 10 days after a 21-day exposure to 5 mg/m(3) of BDS has ended, incomplete lung recovery promotes a pro-biotransformation, pro-oxidant, and pro-inflammatory milieu, which may be a starting point for potential long-term cardio-pulmonary effects.

Dual-Color Fluorescence Imaging to Monitor CYP3A4 and CYP3A7 Expression in Human Hepatic Carcinoma HepG2 and HepaRG Cells

PubMed Central

Kubiura, Musashi; Hayashi, Ayaka; Ohbayashi, Tetsuya; Kazuki, Yasuhiro; Chesné, Christophe; Oshimura, Mitsuo; Tada, Masako

2014-01-01

Human adult hepatocytes expressing CYP3A4, a major cytochrome P450 enzyme, are required for cell-based assays to evaluate the potential risk of drug-drug interactions caused by transcriptional induction of P450 enzymes in early-phase drug discovery and development. However, CYP3A7 is preferentially expressed in premature hepatoblasts and major hepatic carcinoma cell lines. The human hepatocellular carcinoma cell line HepaRG possesses a high self-renewal capacity and can differentiate into hepatic cells similar to human adult hepatocytes in vitro. Transgenic HepaRG cells, in which the expression of fluorescent reporters is regulated by 35 kb regulatory elements of CYP3A4, have a distinct advantage over human hepatocytes isolated by collagenase perfusion, which are unstable in culture. Thus, we created transgenic HepaRG and HepG2 cells by replacing the protein-coding regions of human CYP3A4 and CYP3A7 with enhanced green fluorescent protein (EGFP) and DsRed reporters, respectively, in a bacterial artificial chromosome vector that included whole regulatory elements. The intensity of DsRed fluorescence was initially high during the proliferation of transgenic HepaRG cells. However, most EGFP-positive cells were derived from those in which DsRed fluorescence was extinguished. Comparative analyses in these transgenic clones showed that changes in the total fluorescence intensity of EGFP reflected fold changes in the mRNA level of endogenous CYP3A4. Moreover, CYP3A4 induction was monitored by the increase in EGFP fluorescence. Thus, this assay provides a real-time evaluation system for quality assurance of hepatic differentiation into CYP3A4-expressing cells, unfavourable CYP3A4 induction, and fluorescence-activated cell sorting-mediated enrichment of CYP3A4-expressing hepatocytes based on the total fluorescence intensities of fluorescent reporters, without the need for many time-consuming steps. PMID:25101946

Lack of gp130 expression in hepatocytes attenuates tumor progression in the DEN model.

PubMed

Hatting, M; Spannbauer, M; Peng, J; Al Masaoudi, M; Sellge, G; Nevzorova, Y A; Gassler, N; Liedtke, C; Cubero, F J; Trautwein, C

2015-03-05

Chronic liver inflammation is a crucial event in the development and growth of hepatocellular carcinoma (HCC). Compelling evidence has shown that interleukin-6 (IL-6)/gp130-dependent signaling has a fundamental role in liver carcinogenesis. Thus, in the present study we aimed to investigate the role of gp130 in hepatocytes for the initiation and progression of HCC. Hepatocyte-specific gp130 knockout mice (gp130(Δhepa)) and control animals (gp130(f/f)) were treated with diethylnitrosamine (DEN). The role of gp130 for acute injury (0-144 h post treatment), tumor initiation (24 weeks) and progression (40 weeks) was analyzed. After acute DEN-induced liver injury we observed a reduction in the inflammatory response in gp130(Δhepa) animals as reflected by decreased levels of IL-6 and oncostatin M. The loss of gp130 slightly attenuated the initiation of HCC 24 weeks after DEN treatment. In contrast, 40 weeks after DEN treatment, male and female gp130(Δhepa) mice showed smaller tumors and reduced tumor burden, indicating a role for hepatocyte-specific gp130 expression during HCC progression. Oxidative stress and DNA damage were substantially and similarly increased by DEN in both gp130(f/f) and gp130(Δhepa) animals. However, gp130(Δhepa) livers revealed aberrant STAT5 activation and decreased levels of transforming growth factor-β (TGFβ), pSMAD2/3 and SMAD2, whereas phosphorylation of STAT3 at Tyr705 and Ser727 was absent. Our results indicate that gp130 deletion in hepatocytes reduces progression, but not HCC initiation in the DEN model. Gp130 deletion resulted in STAT3 inhibition but increased STAT5 activation and diminished TGF-dependent signaling. Hence, blocking gp130 in hepatocytes might be an interesting therapeutic target to inhibit the growth of HCC.

Human HepaRG Cells can be Cultured in Hanging-drop Plates for Cytochrome P450 Induction and Function Assays.

PubMed

Murayama, Norie; Usui, Takashi; Slawny, Nicky; Chesné, Christophe; Yamazaki, Hiroshi

2015-01-01

Recent guidance/guidelines for industry recommend that cytochrome P450 induction can be assessed using human hepatocyte enzyme activity and/or mRNA levels to evaluate potential drug- drug interactions. To evaluate time-dependent cytochrome P450 induction precisely, induction of CYP1A2, CYP2B6, and CYP3A4 mRNA was confirmed (>2-fold) by the treatment with omeprazole, phenobarbital, and rifampicin, respectively, for 24 or 48 h on day 3 from the start of culture. After 24 h, the fold induction of CYP1A2 with 3.6 and 1.8x10(4) HepaRG cells per well was lower than that for 7.2x10(4) cells. CYP1A2 induction levels at 24 h were higher than those after 48 h. In contrast, higher CYP2B6 inductions were confirmed after 48 h exposure than after 24 h, independent of the number of cells per well. To help reduce the use of human cryopreserved hepatocytes, typical P450-dependent enzyme activities were investigated in human HepaRG cells cultured in commercial hanging-drop plates. Newly designed 96-well hanging-drop plates were capable of maintaining human CYP3A-dependent midazolam hydroxylation activities for up to 4 days using only 10% of the recommended initial 7.2x10(4) cells per well. Favorable HepaRG function using hanging-drop plates was confirmed by detecting 1'- hydroxymidazolam O-glucuronide on day 3, suggesting an improvement over traditional control plates in which this metabolite can be detected for 24-well plates. These results suggest that the catalytic function and/or induction of CYP1A2, CYP2B6, and CYP3A4 can be readily assessed with reduced numbers of starting HepaRG cells cultured in three-dimensional cultures in drops prepared with hanging-drop plates.

Dual-color fluorescence imaging to monitor CYP3A4 and CYP3A7 expression in human hepatic carcinoma HepG2 and HepaRG cells.

PubMed

Tsuji, Saori; Kawamura, Fumihiko; Kubiura, Musashi; Hayashi, Ayaka; Ohbayashi, Tetsuya; Kazuki, Yasuhiro; Chesné, Christophe; Oshimura, Mitsuo; Tada, Masako

2014-01-01

Human adult hepatocytes expressing CYP3A4, a major cytochrome P450 enzyme, are required for cell-based assays to evaluate the potential risk of drug-drug interactions caused by transcriptional induction of P450 enzymes in early-phase drug discovery and development. However, CYP3A7 is preferentially expressed in premature hepatoblasts and major hepatic carcinoma cell lines. The human hepatocellular carcinoma cell line HepaRG possesses a high self-renewal capacity and can differentiate into hepatic cells similar to human adult hepatocytes in vitro. Transgenic HepaRG cells, in which the expression of fluorescent reporters is regulated by 35 kb regulatory elements of CYP3A4, have a distinct advantage over human hepatocytes isolated by collagenase perfusion, which are unstable in culture. Thus, we created transgenic HepaRG and HepG2 cells by replacing the protein-coding regions of human CYP3A4 and CYP3A7 with enhanced green fluorescent protein (EGFP) and DsRed reporters, respectively, in a bacterial artificial chromosome vector that included whole regulatory elements. The intensity of DsRed fluorescence was initially high during the proliferation of transgenic HepaRG cells. However, most EGFP-positive cells were derived from those in which DsRed fluorescence was extinguished. Comparative analyses in these transgenic clones showed that changes in the total fluorescence intensity of EGFP reflected fold changes in the mRNA level of endogenous CYP3A4. Moreover, CYP3A4 induction was monitored by the increase in EGFP fluorescence. Thus, this assay provides a real-time evaluation system for quality assurance of hepatic differentiation into CYP3A4-expressing cells, unfavourable CYP3A4 induction, and fluorescence-activated cell sorting-mediated enrichment of CYP3A4-expressing hepatocytes based on the total fluorescence intensities of fluorescent reporters, without the need for many time-consuming steps.

Self-Assembled Lipid Nanoparticles for Oral Delivery of Heparin-Coated Iron Oxide Nanoparticles for Theranostic Purposes.

PubMed

Truzzi, Eleonora; Bongio, Chiara; Sacchetti, Francesca; Maretti, Eleonora; Montanari, Monica; Iannuccelli, Valentina; Vismara, Elena; Leo, Eliana

2017-06-09

Recently, solid lipid nanoparticles (SLNs) have attracted increasing attention owing to their potential as an oral delivery system, promoting intestinal absorption in the lymphatic circulation which plays a role in disseminating metastatic cancer cells and infectious agents throughout the body. SLN features can be exploited for the oral delivery of theranostics. Therefore, the aim of this work was to design and characterise self-assembled lipid nanoparticles (SALNs) to encapsulate and stabilise iron oxide nanoparticles non-covalently coated with heparin (Fe@hepa) as a model of a theranostic tool. SALNs were characterised for physico-chemical properties (particle size, surface charge, encapsulation efficiency, in vitro stability, and heparin leakage), as well as in vitro cytotoxicity by methyl thiazole tetrazolium (MTT) assay and cell internalisation in CaCo-2, a cell line model used as an indirect indication of intestinal lymphatic absorption. SALNs of about 180 nm, which are stable in suspension and have a high encapsulation efficiency (>90%) were obtained. SALNs were able to stabilise the heparin coating of Fe@hepa, which are typically unstable in physiological environments. Moreover, SALNs-Fe@hepa showed no cytotoxicity, although their ability to be internalised into CaCo-2 cells was highlighted by confocal microscopy analysis. Therefore, the results indicated that SALNs can be considered as a promising tool to orally deliver theranostic Fe@hepa into the lymphatic circulation, although further in vivo studies are needed to comprehend further potential applications.

Characteristics of insufficiently active participants that benefit from health-enhancing physical activity (HEPA) promotion programs implemented in the sports club setting.

PubMed

Ooms, Linda; Leemrijse, Chantal; Collard, Dorine; Schipper-van Veldhoven, Nicolette; Veenhof, Cindy

2018-06-01

Health-enhancing physical activity (HEPA) promotion programs are implemented in sports clubs. The purpose of this study was to examine the characteristics of the insufficiently active participants that benefit from these programs. Data of three sporting programs, developed for insufficiently active adults, were used for this study. These sporting programs were implemented in different sports clubs in the Netherlands. Participants completed an online questionnaire at baseline and after six months (n = 458). Of this sample, 35.1% (n = 161) was insufficiently active (i.e. not meeting HEPA levels) at baseline. Accordingly, two groups were compared: participants who were insufficiently active at baseline, but increased their physical activity to HEPA levels after six months (activated group, n = 86) versus participants who were insufficiently active both at baseline and after six months (non-activated group, n = 75). Potential associated characteristics (demographic, social, sport history, physical activity) were included as independent variables in bivariate and multivariate logistic regression analyses. The percentage of active participants increased significantly from baseline to six months (from 64.9 to 76.9%, p < 0.05). The bivariate logistic regression analyses showed that participants in the activated group were more likely to receive support from family members with regard to their sport participation (62.8% vs. 42.7%, p = 0.02) and spent more time in moderate-intensity physical activity (128 ± 191 min/week vs. 70 ± 106 min/week, p = 0.02) at baseline compared with participants in the non-activated group. These results were confirmed in the multivariate logistic regression analyses: when receiving support from most family members, there is a 216% increase in the odds of being in the activated group (OR = 2.155; 95% CI: 1.118-4.154, p = 0.02) and for each additional 1 min/week spent in moderate-intensity physical activity, the odds increases with 0.3% (OR = 1.003; 95% CI: 1.001-1.006, p = 0.02). The results suggest that HEPA sporting programs can be used to increase HEPA levels of insufficiently active people, but it seems a challenge to reach the least active ones. It is important that promotional strategies and channels are tailored to the target group. Furthermore, strategies that promote family support may enhance the impact of the programs.

Interacting Multiple Model (IMM) Fifth-Degree Spherical Simplex-Radial Cubature Kalman Filter for Maneuvering Target Tracking

PubMed Central

Liu, Hua; Wu, Wen

2017-01-01

For improving the tracking accuracy and model switching speed of maneuvering target tracking in nonlinear systems, a new algorithm named the interacting multiple model fifth-degree spherical simplex-radial cubature Kalman filter (IMM5thSSRCKF) is proposed in this paper. The new algorithm is a combination of the interacting multiple model (IMM) filter and the fifth-degree spherical simplex-radial cubature Kalman filter (5thSSRCKF). The proposed algorithm makes use of Markov process to describe the switching probability among the models, and uses 5thSSRCKF to deal with the state estimation of each model. The 5thSSRCKF is an improved filter algorithm, which utilizes the fifth-degree spherical simplex-radial rule to improve the filtering accuracy. Finally, the tracking performance of the IMM5thSSRCKF is evaluated by simulation in a typical maneuvering target tracking scenario. Simulation results show that the proposed algorithm has better tracking performance and quicker model switching speed when disposing maneuver models compared with the interacting multiple model unscented Kalman filter (IMMUKF), the interacting multiple model cubature Kalman filter (IMMCKF) and the interacting multiple model fifth-degree cubature Kalman filter (IMM5thCKF). PMID:28608843

Interacting Multiple Model (IMM) Fifth-Degree Spherical Simplex-Radial Cubature Kalman Filter for Maneuvering Target Tracking.

PubMed

Liu, Hua; Wu, Wen

2017-06-13

For improving the tracking accuracy and model switching speed of maneuvering target tracking in nonlinear systems, a new algorithm named the interacting multiple model fifth-degree spherical simplex-radial cubature Kalman filter (IMM5thSSRCKF) is proposed in this paper. The new algorithm is a combination of the interacting multiple model (IMM) filter and the fifth-degree spherical simplex-radial cubature Kalman filter (5thSSRCKF). The proposed algorithm makes use of Markov process to describe the switching probability among the models, and uses 5thSSRCKF to deal with the state estimation of each model. The 5thSSRCKF is an improved filter algorithm, which utilizes the fifth-degree spherical simplex-radial rule to improve the filtering accuracy. Finally, the tracking performance of the IMM5thSSRCKF is evaluated by simulation in a typical maneuvering target tracking scenario. Simulation results show that the proposed algorithm has better tracking performance and quicker model switching speed when disposing maneuver models compared with the interacting multiple model unscented Kalman filter (IMMUKF), the interacting multiple model cubature Kalman filter (IMMCKF) and the interacting multiple model fifth-degree cubature Kalman filter (IMM5thCKF).

Robust Lee local statistic filter for removal of mixed multiplicative and impulse noise

NASA Astrophysics Data System (ADS)

Ponomarenko, Nikolay N.; Lukin, Vladimir V.; Egiazarian, Karen O.; Astola, Jaakko T.

2004-05-01

A robust version of Lee local statistic filter able to effectively suppress the mixed multiplicative and impulse noise in images is proposed. The performance of the proposed modification is studied for a set of test images, several values of multiplicative noise variance, Gaussian and Rayleigh probability density functions of speckle, and different characteris-tics of impulse noise. The advantages of the designed filter in comparison to the conventional Lee local statistic filter and some other filters able to cope with mixed multiplicative+impulse noise are demonstrated.

Multiple Bloch surface waves in visible region of light at the interfaces between rugate filter/rugate filter and rugate filter/dielectric slab/rugate filter

NASA Astrophysics Data System (ADS)

Ullah Manzoor, Habib; Manzoor, Tareq; Hussain, Masroor; Manzoor, Sanaullah; Nazar, Kashif

2018-04-01

Surface electromagnetic waves are the solution of Maxwell’s frequency domain equations at the interface of two dissimilar materials. In this article, two canonical boundary-value problems have been formulated to analyze the multiplicity of electromagnetic surface waves at the interface between two dissimilar materials in the visible region of light. In the first problem, the interface between two semi-infinite rugate filters having symmetric refractive index profiles is considered and in the second problem, to enhance the multiplicity of surface electromagnetic waves, a homogeneous dielectric slab of 400 nm is included between two semi-infinite symmetric rugate filters. Numerical results show that multiple Bloch surface waves of different phase speeds, different polarization states, different degrees of localization and different field profiles are propagated at the interface between two semi-infinite rugate filters. Having two interfaces when a homogeneous dielectric layer is placed between two semi-infinite rugate filters has increased the multiplicity of electromagnetic surface waves.

Combined adaptive multiple subtraction based on optimized event tracing and extended wiener filtering

NASA Astrophysics Data System (ADS)

Tan, Jun; Song, Peng; Li, Jinshan; Wang, Lei; Zhong, Mengxuan; Zhang, Xiaobo

2017-06-01

The surface-related multiple elimination (SRME) method is based on feedback formulation and has become one of the most preferred multiple suppression methods used. However, some differences are apparent between the predicted multiples and those in the source seismic records, which may result in conventional adaptive multiple subtraction methods being barely able to effectively suppress multiples in actual production. This paper introduces a combined adaptive multiple attenuation method based on the optimized event tracing technique and extended Wiener filtering. The method firstly uses multiple records predicted by SRME to generate a multiple velocity spectrum, then separates the original record to an approximate primary record and an approximate multiple record by applying the optimized event tracing method and short-time window FK filtering method. After applying the extended Wiener filtering method, residual multiples in the approximate primary record can then be eliminated and the damaged primary can be restored from the approximate multiple record. This method combines the advantages of multiple elimination based on the optimized event tracing method and the extended Wiener filtering technique. It is an ideal method for suppressing typical hyperbolic and other types of multiples, with the advantage of minimizing damage of the primary. Synthetic and field data tests show that this method produces better multiple elimination results than the traditional multi-channel Wiener filter method and is more suitable for multiple elimination in complicated geological areas.

p65 down-regulates DEPTOR expression in response to LPS stimulation in hepatocytes.

PubMed

Yu, Xiaoling; Jin, Dan; Yu, An; Sun, Jun; Chen, Xiaodong; Yang, Zaiqing

2016-09-01

DEPTOR, a novel endogenous inhibitor of mTOR, plays an important role in regulating the inflammatory response in vascular endothelial cells (ECs) and in mouse skeletal muscle. However, the regulatory mechanism of DEPTOR transcription and its effects on liver inflammation are unknown presently. Here we reported the role of DEPTOR in regulating inflammatory response in mouse liver-derived Hepa1-6 cells and in a mouse model with LPS-induced hepatic inflammation. The results revealed that DEPTOR over-expression in Hepa1-6 liver cells increased the mRNA levels of the pro-inflammatory cytokines interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1). Contrasting results were observed in Hepa1-6 cells with DEPTOR interference. Treatment Hepa1-6 cells with rapamycin, a specific inhibitor of mTORC1, increased MCP-1 mRNA, but have no significant effect on IL-6 mRNA. DEPTOR expression was down-regulated in Hepa1-6 cells with the treatment of inflammatory stimuli LPS or the over-expression of p65/NF-κB, a key inflammatory transcription factor. NF-κB antagonist (PDTC) and inhibitor (IκBα) blocked the effect of LPS on DEPTOR expression. The study in vivo showed that DEPTOR mRNA and protein were significantly reduced in a mouse model with LPS-induced hepatic inflammation, which was accompanied by a concurrent activation of the mTOR signaling pathway. Further, the transcriptional regulation of DEPTOR was explored, which revealed that DEPTOR promoter activity was significantly down-regulated by NF-κB. The progressive deletions and mutations demonstrated that the NF-κB binding motif situated at -145/-127 region is an essential component required for the DEPTOR promoter activity. Chromatin immunoprecipitation (ChIP) assays determined that p65 can directly interact with the DEPTOR promoter DNA. Those results indicate DEPTOR regulates liver inflammation at least partially via mTORC1 pathway, and is down-regulated by LPS through p65. Copyright © 2016 Elsevier B.V. All rights reserved.

Shielded multi-stage EMI noise filter

DOEpatents

Kisner, Roger Allen; Fugate, David Lee

2016-11-08

Electromagnetic interference (EMI) noise filter embodiments and methods for filtering are provided herein. EMI noise filters include multiple signal exclusion enclosures. The multiple signal exclusion enclosures contain filter circuit stages. The signal exclusion enclosures can attenuate noise generated external to the enclosures and/or isolate noise currents generated by the corresponding filter circuits within the enclosures. In certain embodiments, an output of one filter circuit stage is connected to an input of the next filter circuit stage. The multiple signal exclusion enclosures can be chambers formed using conductive partitions to divide an outer signal exclusion enclosure. EMI noise filters can also include mechanisms to maintain the components of the filter circuit stages at a consistent temperature. For example, a metal base plate can distribute heat among filter components, and an insulating material can be positioned inside signal exclusion enclosures.

Treatment with Parkinsonia aculeata combats insulin resistance-induced oxidative stress through the increase in PPARγ/CuZn-SOD axis expression in diet-induced obesity mice.

PubMed

Araújo, Tiago Gomes; Oliveira, Alexandre Gabarra; Vecina, Juliana Falcato; Marin, Rodrigo Miguel; Franco, Eryvelton Souza; Abdalla Saad, Mario J; de Sousa Maia, Maria Bernadete

2016-08-01

Parkinsonia aculeata L. (Caesalpiniaceae) is a traditional ethnomedicine and has been used for the empiric treatment of hyperglycemia, without scientific background. Mechanistic analyses at molecular level from the antioxidant mechanism observed by P. aculeata are required. Herein the effects of the treatment by hydroethanolic extract partitioned with ethyl acetate of P. aculeata aerial parts (HEPa/EtOAc) in mice fed a high-fat diet that share many obesity phenotypes with humans were evaluated. The animals were treated orally with HEPa/EtOAc (125 and 250 mg/kg/day) and pioglitazone (5 mg/kg/day), for 16 days. After the treatment, HEPa/EtOAc reduced fasting serum glucose and insulin levels, as well as homeostasis model assessment for insulin resistance. In addition, an improvement in glucose intolerance was also observed. Indeed, a reduction in the circulating levels of TNF-α and IL-6 was also observed. Furthermore, at molecular level, it was demonstrated that the HEPa/EtOAc treatment was able to improve these physiological parameters, through the activation of peroxisome proliferator-activated receptor γ (PPARγ) per si, as well as the enhancement of antioxidant mechanism by an increase in PPARγ/Cu(2+), Zn(2+)-superoxide dismutase (CuZn-SOD) axis expression in liver and adipose tissue. In sum, P. aculeata is effective to improve insulin resistance in a mouse model of obesity and this effect seems to involve the antioxidant and anti-inflammatory mechanisms through the increase in PPARγ/CuZn-SOD axis expression.

Recombinant Escherichia coli Trx-JZTX-III represses the proliferation of mouse hepatocellular carcinoma cells through induction of cell cycle arrest.

PubMed

Sun, Mei-Na; Zhao, Xue-Jiao; Zhao, Han-Dong; Zhang, Wei-Guang; Li, Feng-Lan; Chen, Ming-Zi; Li, Hui; Li, Guangchao

2013-06-01

The aim of the present study was to investigate the effects of recombinant Escherichia coli (E. coli) Trx-jingzhaotoxin (JZTX)-III on cell growth in the mouse hepatocellular carcinoma (HCC) cell line Hepa1-6. The JZTX-III gene sequence was synthesized and cloned into the pET-32a(+) vector to construct the recombinant fusion protein Trx-JZTX-III, which was subsequently purified. Hepa1-6 cells were treated with 0 to 1,000-µg/ml concentrations of Trx-JZTX-III; this was demonstrated to affect cell viability, as determined by the 3-(4,5-dimethylthiazol‑2-yl)-2,5-diphenyltetra-zolium bromide (MTT) assay. The expression of the proliferating cell nuclear antigen (PCNA) protein was investigated using western blot analysis. A colony formation assay was used to determine Hepa1-6 cell proliferation, and the migration ability of cells was determined using a wound‑healing assay. Additionally, flow cytometry was employed to observe changes in the cell cycle. The MTT assay and quantification of PCNA expression indicated that recombinant E. coli Trx-JZTX-III significantly repressed the proliferation of Hepa1-6 cells. Colony formation and the migration of malignant cells was inhibited following treatment with recombinant E. coli Trx-JZTX-III. Flow cytometry showed that recombinant E. coli Trx-JZTX-III induced G0/G1 cell cycle arrest. In conclusion, recombinant E. coli Trx-JZTX-III functions as a tumor suppressor drug in mouse HCC and its underlying mechanism may involve the induction of G0/G1 cell cycle arrest.

Three-dimensional HepaRG model as an attractive tool for toxicity testing.

PubMed

Leite, Sofia B; Wilk-Zasadna, Iwona; Zaldivar, Jose M; Airola, Elodie; Reis-Fernandes, Marcos A; Mennecozzi, Milena; Guguen-Guillouzo, Christiane; Chesne, Christopher; Guillou, Claude; Alves, Paula M; Coecke, Sandra

2012-11-01

The culture of HepaRG cells as three dimensional (3D) structures in the spinner-bioreactor may represent added value as a hepatic system for toxicological purposes. The use of a cost-effective commercially available bioreactor, which is compatible with high-throughput cell analysis, constitutes an attractive approach for routine use in the drug testing industry. In order to assess specific aspects of the biotransformation capacity of the bioreactor-based HepaRG system, the induction of CYP450 enzymes (i.e., CYP1A2, 2B6, 2C9, and 3A4) and the activity of the phase II enzyme, uridine diphosphate glucuronoltransferase (UGT), were tested. The long-term functionality of the system was demonstrated by 7-week stable profiles of albumin secretion, CYP3A4 induction, and UGT activities. Immunofluorescence-based staining showed formation of tissue-like arrangements including bile canaliculi-like structures and polar distribution of transporters. The use of in silico models to analyze the in vitro data related to hepatotoxic activity of acetaminophen (APAP) demonstrated the advantage of the integration of kinetic and dynamic aspects for a better understanding of the in vitro cell behavior. The bioactivation of APAP and its related cytotoxicity was assessed in a system compatible to high-throughput screening. The approach also proved to be a good strategy to reduce the time necessary to obtain fully differentiated cell cultures. In conclusion, HepaRG cells cultured in 3D spinner-bioreactors are an attractive tool for toxicological studies, showing a liver-like performance and demonstrating a practical applicability for toxicodynamic approaches.

The HepaRG cell line: biological properties and relevance as a tool for cell biology, drug metabolism, and virology studies.

PubMed

Marion, Marie-Jeanne; Hantz, Olivier; Durantel, David

2010-01-01

Liver progenitor cells may play an important role in carcinogenesis in vivo and represent therefore useful cellular materials for in vitro studies. The HepaRG cell line, which is a human bipotent progenitor cell line capable to differentiate toward two different cell phenotypes (i.e., biliary-like and hepatocyte-like cells), has been established from a liver tumor associated with chronic hepatitis C. This cell line represents a valuable alternative to ex vivo cultivated primary human hepatocytes (PHH), as HepaRG cells share some features and properties with adult hepatocytes. The cell line is particularly useful to evaluate drugs and perform drug metabolism studies, as many detoxifying enzymes are expressed and functional. It is also an interesting tool to study some aspect of progenitor biology (e.g., differentiation process), carcinogenesis, and the infection by some pathogens for which the cell line is permissive (e.g., HBV infection). Overall, this chapter gives a concise overview of the biological properties and potential applications of this cell line.

3D spheroid cultures improve the metabolic gene expression profiles of HepaRG cells.

PubMed

Takahashi, Yu; Hori, Yuji; Yamamoto, Tomohisa; Urashima, Toshiki; Ohara, Yasunori; Tanaka, Hideo

2015-05-07

3D (three-dimensional) cultures are considered to be an effective method for toxicological studies; however, little evidence has been reported whether 3D cultures have an impact on hepatocellular physiology regarding lipid or glucose metabolism. In the present study, we conducted physiological characterization of hepatoma cell lines HepG2 and HepaRG cells cultured in 3D conditions using a hanging drop method to verify the effect of culture environment on cellular responses. Apo (Apolipoprotein)B as well as albumin secretion was augmented by 3D cultures. Expression of genes related to not only drug, but also glucose and lipid metabolism were significantly enhanced in 3D cultured HepaRG spheroids. Furthermore, mRNA levels of CYP (cytochrome P450) enzymes following exposure to corresponding inducers increased under the 3D condition. These data suggest that this simple 3D culture system without any special biomaterials can improve liver-specific characteristics including lipid metabolism. Considering that the system enables high-throughput assay, it may become a powerful tool for compound screening concerning hepatocellular responses in order to identify potential drugs. © 2015 Authors.

Testing chemical carcinogenicity by using a transcriptomics HepaRG-based model?

PubMed Central

Doktorova, T. Y.; Yildirimman, Reha; Ceelen, Liesbeth; Vilardell, Mireia; Vanhaecke, Tamara; Vinken, Mathieu; Ates, Gamze; Heymans, Anja; Gmuender, Hans; Bort, Roque; Corvi, Raffaella; Phrakonkham, Pascal; Li, Ruoya; Mouchet, Nicolas; Chesne, Christophe; van Delft, Joost; Kleinjans, Jos; Castell, Jose; Herwig, Ralf; Rogiers, Vera

2014-01-01

The EU FP6 project carcinoGENOMICS explored the combination of toxicogenomics and in vitro cell culture models for identifying organotypical genotoxic- and non-genotoxic carcinogen-specific gene signatures. Here the performance of its gene classifier, derived from exposure of metabolically competent human HepaRG cells to prototypical non-carcinogens (10 compounds) and hepatocarcinogens (20 compounds), is reported. Analysis of the data at the gene and the pathway level by using independent biostatistical approaches showed a distinct separation of genotoxic from non-genotoxic hepatocarcinogens and non-carcinogens (up to 88 % correct prediction). The most characteristic pathway responding to genotoxic exposure was DNA damage. Interlaboratory reproducibility was assessed by blindly testing of three compounds, from the set of 30 compounds, by three independent laboratories. Subsequent classification of these compounds resulted in correct prediction of the genotoxicants. As expected, results on the non-genotoxic carcinogens and the non-carcinogens were less predictive. In conclusion, the combination of transcriptomics with the HepaRG in vitro cell model provides a potential weight of evidence approach for the evaluation of the genotoxic potential of chemical substances. PMID:26417288

A problem of hospital hygiene: the presence of aspergilli in hospital wards with different air-conditioning features.

PubMed

Perdelli, Fernanda; Sartini, Marina; Spagnolo, Anna Maria; Dallera, Maurizio; Lombardi, Roberto; Cristina, Maria Luisa

2006-06-01

A total of 1,030 microbiological samples were taken in 3 hospital wards with different air-conditioning features: no conditioning system (ward A), a conditioning system equipped with minimum efficiency reporting value (MERV) filters (ward B), and a conditioning system thoroughly maintained and equipped with high-efficiency particulate air (HEPA) filters (absolute) (ward C). The air in each ward was sampled, and the bacterial and fungal concentrations were determined by active and passive methods. The concentration of fungi on surfaces was also determined. Active sampling showed positive samples in wards A and B only, with average values of 0.50 colony-forming units (CFU)/m(3) (95% CI, 0.30 to 0.70) in A and 0.16 CFU/m(3) (95% CI, 0.13 to 0.20) in B. Passive sampling was positive only in ward A (mean, 0.14 CFU/cm(2)/h; 95% CI, 0.13 to 0.15). Aspergillus was found in 27% and 22% of sampled surfaces in wards A and B, respectively, but in no samples from ward C. The most commonly found species was A. fumigatus (76% of cases in A and 34% of cases in B). The results show that the use of air-conditioning systems markedly reduces the concentration of aspergilli in the environment. Proper maintenance of these systems is clearly fundamental if their efficacy is to be ensured.

PubMed Central

SPAGNOLO, A.M.; OTTRIA, G.; AMICIZIA, D.; PERDELLI, F.

2013-01-01

Summary Surgical site infections (SSI) account for 14% to 17% of all hospital-acquired infections and 38% of nosocomial infections in surgical patients. SSI remain a substantial cause of morbidity and death, possibly because of the larger numbers of elderly surgical patients or those with a variety of chronic and immunocompromising conditions, and emergence of antibiotic-resistant microorganisms. Factors causing surgical site infection are multifarious. Several studies have identified the main patient-related (endogenous risk factors) and procedure-related (external risk factors) factors that influence the risk of SSI. The rate of surgical wound infections is strongly influenced by operating theatre quality, too. A safe and salubrious operating theatre is an environment in which all sources of pollution and any micro-environmental alterations are kept strictly under control. This can be achieved only through careful planning, maintenance and periodic checks, as well as proper ongoing training for staff. Many international scientific societies have produced guidelines regarding the environmental features of operating theatres (positive pressure, exchanges of filtered air per hour, air-conditioning systems with HEPA filters, etc.) and issued recommendations on healthcare-associated infection, including SSI, concerning surveillance methods, intervention to actively prevent SSI and approaches to monitoring the implementation of such strategies. Therefore, the prevention of SSI requires a multidisciplinary approach and the commitment of all concerned, including that of those who are responsible for the design, layout and functioning of operating theatres. PMID:24783890

An Improved Interacting Multiple Model Filtering Algorithm Based on the Cubature Kalman Filter for Maneuvering Target Tracking.

PubMed

Zhu, Wei; Wang, Wei; Yuan, Gannan

2016-06-01

In order to improve the tracking accuracy, model estimation accuracy and quick response of multiple model maneuvering target tracking, the interacting multiple models five degree cubature Kalman filter (IMM5CKF) is proposed in this paper. In the proposed algorithm, the interacting multiple models (IMM) algorithm processes all the models through a Markov Chain to simultaneously enhance the model tracking accuracy of target tracking. Then a five degree cubature Kalman filter (5CKF) evaluates the surface integral by a higher but deterministic odd ordered spherical cubature rule to improve the tracking accuracy and the model switch sensitivity of the IMM algorithm. Finally, the simulation results demonstrate that the proposed algorithm exhibits quick and smooth switching when disposing different maneuver models, and it also performs better than the interacting multiple models cubature Kalman filter (IMMCKF), interacting multiple models unscented Kalman filter (IMMUKF), 5CKF and the optimal mode transition matrix IMM (OMTM-IMM).

Stereological Analysis of Liver Biopsy Histology Sections as a Reference Standard for Validating Non-Invasive Liver Fat Fraction Measurements by MRI

PubMed Central

St. Pierre, Tim G.; House, Michael J.; Bangma, Sander J.; Pang, Wenjie; Bathgate, Andrew; Gan, Eng K.; Ayonrinde, Oyekoya T.; Bhathal, Prithi S.; Clouston, Andrew; Olynyk, John K.; Adams, Leon A.

2016-01-01

Background and Aims Validation of non-invasive methods of liver fat quantification requires a reference standard. However, using standard histopathology assessment of liver biopsies is problematical because of poor repeatability. We aimed to assess a stereological method of measuring volumetric liver fat fraction (VLFF) in liver biopsies and to use the method to validate a magnetic resonance imaging method for measurement of VLFF. Methods VLFFs were measured in 59 subjects (1) by three independent analysts using a stereological point counting technique combined with the Delesse principle on liver biopsy histological sections and (2) by three independent analysts using the HepaFat-Scan® technique on magnetic resonance images of the liver. Bland Altman statistics and intraclass correlation (IC) were used to assess the repeatability of each method and the bias between the methods of liver fat fraction measurement. Results Inter-analyst repeatability coefficients for the stereology and HepaFat-Scan® methods were 8.2 (95% CI 7.7–8.8)% and 2.4 (95% CI 2.2–2.5)% VLFF respectively. IC coefficients were 0.86 (95% CI 0.69–0.93) and 0.990 (95% CI 0.985–0.994) respectively. Small biases (≤3.4%) were observable between two pairs of analysts using stereology while no significant biases were observable between any of the three pairs of analysts using HepaFat-Scan®. A bias of 1.4±0.5% VLFF was observed between the HepaFat-Scan® method and the stereological method. Conclusions Repeatability of the stereological method is superior to the previously reported performance of assessment of hepatic steatosis by histopathologists and is a suitable reference standard for validating non-invasive methods of measurement of VLFF. PMID:27501242

Characterizing the mechanism of thiazolidinedione-induced hepatotoxicity: An in vitro model in mitochondria

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

Hu, Dan; Wu, Chun-qi; Li, Ze-jun

Objective: To characterize the mechanism of action of thiazolidinedione (TZD)-induced liver mitochondrial toxicity caused by troglitazone, rosiglitazone, and pioglitazone in HepaRG cells. Methods: Human hepatoma cells (HepaRG) were treated with troglitazone, rosiglitazone, or pioglitazone (12.5, 25, and 50 μM) for 48 h. The Seahorse Biosciences XF24 Flux Analyzer was used to measure mitochondrial oxygen consumption. The effect of TZDs on reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were detected by flow cytometry. The mitochondrial ultrastructure of HepaRG cells was observed under a transmission electrical microscope (TEM). mtDNA content was evaluated by real-time PCR, and ATP content and mitochondrialmore » respiratory chain (MRC) complex I, II, III, IV activity were measured via chemiluminescence. Results were considered statistically significant at p < 0.05. Results: Among the three drugs, troglitazone exhibited the highest potency, followed by rosiglitazone, and then pioglitazone. The TZDs caused varying degrees of mitochondrial respiratory function disorders including decreases in oxygen consumption, MRC activity, and ATP level, and an elevation in ROS level. TZD treatment resulted in mtDNA content decline, reduction in MMP, and alterations of mitochondrial structure. Conclusion: All investigated TZDs show a certain degree of mitochondrial toxicity, with troglitazone exhibiting the highest potency. The underlying mechanism of TZD-induced hepatotoxicity may be associated with alterations in mitochondrial respiratory function disorders, oxidative stress, and changes in membrane permeability. These parameters may be used early in drug development to further optimize risk:benefit profiles. - Highlights: • We compared three TZD mitochondrial toxicity characteristics in HepaRG cells. • TZD induced respiratory disorders and mitochondrial structural damage. • Mitochondrial toxicity evaluation presents guidance value for hepatotoxicity.« less

Metabotropic glutamate receptor 5 mediates the suppressive effect of 6-OHDA-induced model of Parkinson's disease on liver cancer.

PubMed

Xi, Shao-Song; Bai, Xiao-Xu; Gu, Li; Bao, Li-Hui; Yang, Hui-Min; An, Wei; Wang, Xiao-Min; Zhang, Hong

2017-07-01

Numerous epidemiological studies suggested that there is a variable cancer risk in patients with Parkinson's disease (PD). However, the underlying mechanisms remain unclear. In the present study, the role of metabotropic glutamate receptor 5 (mGluR5) has been investigated in 6-hydroxydopamine (6-OHDA)-induced PD combined with liver cancer both in vitro and in vivo. We found that PD cellular model from 6-OHDA-lesioned MN9D cells suppressed the growth, migration, and invasion of Hepa1-6 cells via down-regulation of mGluR5-mediated ERK and Akt pathway. The application of 2-methyl-6-(phenylethyl)-pyridine and knockdown of mGluR5 further decreased the effect on Hepa-1-6 cells when co-cultured with conditioned media. The effect was increased by (S)-3,5-dihydroxyphenylglycine and overexpression of mGluR5. Moreover, more release of glutamate from 6-OHDA-lesioned MN9D cells suppressed mGluR5-mediated effect of Hepa1-6 cells. Application of riluzole eliminated the increased glutamate release induced by 6-OHDA in MN9D cells and aggravated the suppressive effect on Hepa-1-6 cells. In addition, the growth of implanted liver cancer was inhibited in 6-OHDA induced PD-like rats, and was associated with increased glutamate release in the serum and down-regulation of mGluR5 in tumor tissue. Collectively, these results indicate that selective antagonism of glutamate and mGluR5 has a potentially beneficial effect in both liver cancer and PD, and thus may provide more understanding for the clinical investigation and further an additional therapeutic target for these two diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Financial Burden of Public Health Responses to Hepatitis A Cases Among Food Handlers, 2012-2014.

PubMed

Morey, Rebecca J; Collier, Melissa G; Nelson, Noele P

When food handlers become ill with hepatitis A virus (HAV) infection, state and local health departments must assess the risk of HAV transmission through prepared food and recommend or provide postexposure prophylaxis (PEP) for those at risk for HAV infection. Providing PEP (eg, hepatitis A [HepA] vaccine or immunoglobulin), however, is costly. To describe the burden of these responses on state and local health departments, we determined the number of public health responses to HAV infections among food handlers by reviewing public internet sources of media articles. We then contacted each health department to collect data on whether PEP was recommended to food handlers or restaurant patrons, the number of PEP doses given, the number of HepA vaccine or immunoglobulin doses given as PEP, and the mean number of health department person-hours required for the response. Of 32 public health responses identified from Twitter, HealthMap, and Google alerts from January 1, 2012, to December 31, 2014, a total of 27 (84%) recommended PEP for other food handlers or restaurant patrons or both. Per public health response, the mean cost per dose of the HepA vaccine or immunoglobulin was $34 139; the mean personnel cost per response was $7329; and the total mean cost of each response was $41 468. PEP is expensive. Less aggressive approaches to PEP, such as limiting PEP to fellow food handlers in nonoutbreak situations, should be considered in the postvaccination era. HepA vaccine for PEP provides long-term immunity and can be used when immunoglobulin is unavailable or cannot be administered within 14 days of exposure to HAV.

Multiple attenuation to reflection seismic data using Radon filter and Wave Equation Multiple Rejection (WEMR) method

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

Erlangga, Mokhammad Puput

Separation between signal and noise, incoherent or coherent, is important in seismic data processing. Although we have processed the seismic data, the coherent noise is still mixing with the primary signal. Multiple reflections are a kind of coherent noise. In this research, we processed seismic data to attenuate multiple reflections in the both synthetic and real seismic data of Mentawai. There are several methods to attenuate multiple reflection, one of them is Radon filter method that discriminates between primary reflection and multiple reflection in the τ-p domain based on move out difference between primary reflection and multiple reflection. However, inmore » case where the move out difference is too small, the Radon filter method is not enough to attenuate the multiple reflections. The Radon filter also produces the artifacts on the gathers data. Except the Radon filter method, we also use the Wave Equation Multiple Elimination (WEMR) method to attenuate the long period multiple reflection. The WEMR method can attenuate the long period multiple reflection based on wave equation inversion. Refer to the inversion of wave equation and the magnitude of the seismic wave amplitude that observed on the free surface, we get the water bottom reflectivity which is used to eliminate the multiple reflections. The WEMR method does not depend on the move out difference to attenuate the long period multiple reflection. Therefore, the WEMR method can be applied to the seismic data which has small move out difference as the Mentawai seismic data. The small move out difference on the Mentawai seismic data is caused by the restrictiveness of far offset, which is only 705 meter. We compared the real free multiple stacking data after processing with Radon filter and WEMR process. The conclusion is the WEMR method can more attenuate the long period multiple reflection than the Radon filter method on the real (Mentawai) seismic data.« less

Effect of heat and moisture exchanger (HME) positioning on inspiratory gas humidification.

PubMed

Inui, Daisuke; Oto, Jun; Nishimura, Masaji

2006-08-08

In mechanically ventilated patients, we investigated how positioning the heat and moisture exchanger (HME) at different places on the ventilator circuit affected inspiratory gas humidification. Absolute humidity (AH) and temperature (TEMP) at the proximal end of endotracheal tube (ETT) were measured in ten mechanically ventilated patients. The HME was connected either directly proximal to the ETT (Site 1) or at before the circuit Y-piece (Site 2: distance from proximal end of ETT and Site 2 was about 19 cm) (Figure. 1). Two devices, Hygrobac S (Mallinckrodt Dar, Mirandola, Italy) and Thermovent HEPA (Smiths Medical International Ltd., Kent, UK) were tested. AH and TEMP were measured with a hygrometer (Moiscope, MERA Co., Ltd., Tokyo, Japan). Hygrobac S provided significantly higher AH and TEMP at both sites than Thermovent HEPA. Both Hygrobac S and with Thermovent HEPA provided significantly higher AH and TEMP when placed proximally to the ETT. Although placement proximal to the ETT improved both AH and TEMP in both HMEs tested, one HME performed better in the distal position than the other HME in the proximal position. We conclude the both the type and placement of HME can make a significant difference in maintaining AH and TEMP during adult ventilation.

Chemoembolization of Hepatocellular Carcinoma with Hepasphere 30–60 μm. Safety and Efficacy Study

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

Malagari, Katerina, E-mail: kmalag@otenet.gr; Pomoni, Maria, E-mail: mpomoni@mail.gr; Moschouris, Hippokratis, E-mail: hipmosch@gmail.com

2013-11-22

Background: This study examined the safety, pharmacokinetics, and efficacy of transarterial chemoembolization of hepatocellular carcinoma (HCC) using a newly developed size of a superabsorbent polymer drug-eluting embolic material.MethodsForty-five patients with documented HCC (Child–Pugh score A/B: 55.5 %/44.5 %) were embolized with HepaSphere microspheres 30–60 μm with escalation of lesion, dose, and frequency of re-embolization. Local response was evaluated with modified response evaluation criteria in solid tumors (mRECIST). Plasma levels of doxorubicin were measured in 24 patients at baseline and at 5, 20, 40, 60, and 120 min, at 6, 24, and 48 h, and at 7 days, respectively, to determine doxorubicin in plasma (Cmax) and areamore » under the curve (AUC). Measurements of three patients who underwent lipiodol-based conventional chemoembolization (c-TACE) were also performed.ResultsTACE with HepaSphere was well tolerated with an acceptable safety profile and no 30-day mortality. Response rates were calculated on intention-to-treat basis with complete response (CR) in 17.8 % reaching 22.2 % for the target lesion. Overall partial response (PR) was seen in 51.1 %, stable disease in 20 %, and progressive disease in 11.1 % of patients. Overall objective response (CR + PR), including patients treated at all dosages of doxorubicin, was seen in 68.9 % of cases. After a median follow-up of 15.6 months, 1-year survival is 100 %. Doxorubicin AUC was significantly lower in patients with HepaSphere 30–60 μm (35,195 ± 27,873 ng × min/ml) than in patients with conventional TACE (103,960 ± 16,652 ng × min/ml; p = 0.009). Cmax was also significantly lower with HepaSphere 30–60 μm (83.9 ± 32.1 ng/ml) compared with c-TACE (761.3 ± 58.8 ng/ml; p = 0.002).ConclusionHepaSphere 30–60 μm is an effective drug-eluting embolic material with a favourable pharmacokinetic profile.« less

Self-reported hepatitis A vaccination as a predictor of hepatitis A virus antibody protection in U.S. adults: National Health and Nutrition Examination Survey 2007-2012.

PubMed

Denniston, Maxine M; Monina Klevens, R; Jiles, Ruth B; Murphy, Trudy V

2015-07-31

To estimate the predictive value of self-reported hepatitis A vaccine (HepA) receipt for the presence of hepatitis A virus (HAV) antibody (anti-HAV) from either past infection or vaccination, as an indicator of HAV protection. Using 2007-2012 National Health and Nutrition Examination Survey data, we assigned participants to 4 groups based on self-reported HepA receipt and anti-HAV results. We compared characteristics across groups and calculated three measures of agreement between self-report and serologic status (anti-HAV): percentage concordance, and positive (PPV) and negative (NPV) predictive values. Using logistic regression we investigated factors associated with agreement between self-reported vaccination status and serological results. Demographic and other characteristics varied significantly across the 4 groups. Overall agreement between self-reported HepA receipt and serological results was 63.6% (95% confidence interval [CI] 61.9-65.2); PPV and NPV of self-reported vaccination status for serological result were 47.0% (95% CI 44.2-49.8) and 69.4% (95% CI 67.0-71.8), respectively. Mexican American and foreign-born adults had the highest PPVs (71.5% [95% CI 65.9-76.5], and 75.8% [95% CI 71.4-79.7]) and the lowest NPVs (21.8% [95% CI 18.5-25.4], and 20.0% [95% CI 17.2-23.1]), respectively. Young (ages 20-29 years), US-born, and non-Hispanic White adults had the lowest PPVs (37.9% [95% CI 34.5-41.5], 39.1% [95% CI, 36.0-42.3], and 39.8% [36.1-43.7]), and the highest NPVs (76.9% [95% CI 72.2-81.0, 78.5% [95% CI 76.5-80.4)], and 80.6% [95% CI 78.2-82.8), respectively. Multivariate logistic analyses found age, race/ethnicity, education, place of birth and income to be significantly associated with agreement between self-reported vaccination status and serological results. When assessing hepatitis A protection, self-report of not having received HepA was most likely to identify persons at risk for hepatitis A infection (no anti-HAV) among young, US-born and non-Hispanic White adults, and self-report of HepA receipt was least likely to be reliable among adults with the same characteristics. Copyright © 2015. Published by Elsevier Ltd.

Changes in hepatitis A and B vaccination rates in adult patients with chronic liver diseases and diabetes in the U.S. population.

PubMed

Younossi, Zobair M; Stepanova, Maria

2011-10-01

Professional societies recommend hepatitis A and hepatitis B immunization for individuals with chronic liver disease (CLD), but the degree of implementation is unknown. Data were obtained from the National Health and Nutrition Examination Surveys (NHANES) conducted in 1999-2008. For the entire study population and for those with CLD and diabetes, we determined the rates and independent predictors of history of hepatitis A and hepatitis B (HepA and HepB) vaccinations, of their effectiveness, and of seroprevalence of hepatitis A antibody and anti-HB surface antibody. In total, 24,871 participants from NHANES were included: 14,886 (1999-2004) and 9,985 (2005-2008). Of these individuals, 14.0% had CLD and 8.6% had diabetes. During the study period, HepA vaccination in CLD increased from 13.3% ± 1.0% to 20.0% ± 1.5%, HepB vaccination increased from 23.4% ± 1.2% to 32.1% ± 1.5%. Of subtypes of CLD, HepA vaccination rates increased only in nonalcoholic fatty liver disease (NAFLD), whereas HepB vaccination increased for patients with hepatitis C and nonalcoholic fatty liver disease. In the diabetic cohort, HepA vaccination rates increased from 9.3% ± 1.1% to 15.4% ± 1.7% and HepB rates increased from 15.2% ± 1.5% to 22.4% ± 1.7%. All changes were similar to those observed in the general population. The quality measure (QM) for HepA in the general population decreased from 44.4% ± 1.2% in 1999-2004 to 41.7% ± 1.9% in 2005-2008, and similar changes were noted for all subcohorts. On the other hand, QM for HepB increased from 31.7% ± 0.9% to 40.7% ± 1.0% in the population, whereas no changes in QM were noted in any diagnostic cohort except for NAFLD. Although vaccination rates in CLD and diabetic cohorts are increasing, they remain low. Given the public health implications of acute hepatitis A and hepatitis B in patients with CLD, better implementation of the vaccination recommendations for these populations is warranted. Copyright © 2011 American Association for the Study of Liver Diseases.

Economical Implementation of a Filter Engine in an FPGA

NASA Technical Reports Server (NTRS)

Kowalski, James E.

2009-01-01

A logic design has been conceived for a field-programmable gate array (FPGA) that would implement a complex system of multiple digital state-space filters. The main innovative aspect of this design lies in providing for reuse of parts of the FPGA hardware to perform different parts of the filter computations at different times, in such a manner as to enable the timely performance of all required computations in the face of limitations on available FPGA hardware resources. The implementation of the digital state-space filter involves matrix vector multiplications, which, in the absence of the present innovation, would ordinarily necessitate some multiplexing of vector elements and/or routing of data flows along multiple paths. The design concept calls for implementing vector registers as shift registers to simplify operand access to multipliers and accumulators, obviating both multiplexing and routing of data along multiple paths. Each vector register would be reused for different parts of a calculation. Outputs would always be drawn from the same register, and inputs would always be loaded into the same register. A simple state machine would control each filter. The output of a given filter would be passed to the next filter, accompanied by a "valid" signal, which would start the state machine of the next filter. Multiple filter modules would share a multiplication/accumulation arithmetic unit. The filter computations would be timed by use of a clock having a frequency high enough, relative to the input and output data rate, to provide enough cycles for matrix and vector arithmetic operations. This design concept could prove beneficial in numerous applications in which digital filters are used and/or vectors are multiplied by coefficient matrices. Examples of such applications include general signal processing, filtering of signals in control systems, processing of geophysical measurements, and medical imaging. For these and other applications, it could be advantageous to combine compact FPGA digital filter implementations with other application-specific logic implementations on single integrated-circuit chips. An FPGA could readily be tailored to implement a variety of filters because the filter coefficients would be loaded into memory at startup.

Mechanical degradation temperature of waste storage materials

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

Fink, M.C.; Meyer, M.L.

1993-05-13

Heat loading analysis of the Solid Waste Disposal Facility (SWDF) waste storage configurations show the containers may exceed 90{degrees}C without any radioactive decay heat contribution. Contamination containment is primarily controlled in TRU waste packaging by using multiple bag layers of polyvinyl chloride and polyethylene. Since literature values indicate that these thermoplastic materials can begin mechanical degradation at 66{degrees}C, there was concern that the containment layers could be breached by heating. To better define the mechanical degradation temperature limits for the materials, a series of heating tests were conducted over a fifteen and thirty minute time interval. Samples of a low-densitymore » polyethylene (LDPE) bag, a high-density polyethylene (HDPE) high efficiency particulate air filter (HEPA) container, PVC bag and sealing tape were heated in a convection oven to temperatures ranging from 90 to 185{degrees}C. The following temperature limits are recommended for each of the tested materials: (1) low-density polyethylene -- 110{degrees}C; (2) polyvinyl chloride -- 130{degrees}C; (3) high-density polyethylene -- 140{degrees}C; (4) sealing tape -- 140{degrees}C. Testing with LDPE and PVC at temperatures ranging from 110 to 130{degrees}C for 60 and 120 minutes also showed no observable differences between the samples exposed at 15 and 30 minute intervals. Although these observed temperature limits differ from the literature values, the trend of HDPE having a higher temperature than LDPE is consistent with the reference literature. Experimental observations indicate that the HDPE softens at elevated temperatures, but will retain its shape upon cooling. In SWDF storage practices, this might indicate some distortion of the waste container, but catastrophic failure of the liner due to elevated temperatures (<185{degrees}C) is not anticipated.« less

An accelerated non-Gaussianity based multichannel predictive deconvolution method with the limited supporting region of filters

NASA Astrophysics Data System (ADS)

Li, Zhong-xiao; Li, Zhen-chun

2016-09-01

The multichannel predictive deconvolution can be conducted in overlapping temporal and spatial data windows to solve the 2D predictive filter for multiple removal. Generally, the 2D predictive filter can better remove multiples at the cost of more computation time compared with the 1D predictive filter. In this paper we first use the cross-correlation strategy to determine the limited supporting region of filters where the coefficients play a major role for multiple removal in the filter coefficient space. To solve the 2D predictive filter the traditional multichannel predictive deconvolution uses the least squares (LS) algorithm, which requires primaries and multiples are orthogonal. To relax the orthogonality assumption the iterative reweighted least squares (IRLS) algorithm and the fast iterative shrinkage thresholding (FIST) algorithm have been used to solve the 2D predictive filter in the multichannel predictive deconvolution with the non-Gaussian maximization (L1 norm minimization) constraint of primaries. The FIST algorithm has been demonstrated as a faster alternative to the IRLS algorithm. In this paper we introduce the FIST algorithm to solve the filter coefficients in the limited supporting region of filters. Compared with the FIST based multichannel predictive deconvolution without the limited supporting region of filters the proposed method can reduce the computation burden effectively while achieving a similar accuracy. Additionally, the proposed method can better balance multiple removal and primary preservation than the traditional LS based multichannel predictive deconvolution and FIST based single channel predictive deconvolution. Synthetic and field data sets demonstrate the effectiveness of the proposed method.

Low Complexity Track Initialization and Fusion for Multi-Modal Sensor Networks

DTIC Science & Technology

2012-11-08

feature was demonstrated via the simulations. Aerospace 2011work further documents our investigation of multiple target tracking filters in...bounds that determine how well a sensor network can resolve and localize multiple targets as a function of the operating parameters such as sensor...probability density (PHD) filter for binary measurements using proximity sensors. 15. SUBJECT TERMS proximity sensors, PHD filter, multiple

Design and fabrication of a glovebox for the Plasma Hearth Process radioactive bench-scale system

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

Wahlquist, D.R.

This paper presents some of the design considerations and fabrication techniques for building a glovebox for the Plasma Hearth Process (PHP) radioactive bench-scale system. The PHP radioactive bench-scale system uses a plasma torch to process a variety of radioactive materials into a final vitrified waste form. The processed waste will contain plutonium and trace amounts of other radioactive materials. The glovebox used in this system is located directly below the plasma chamber and is called the Hearth Handling Enclosure (HHE). The HHE is designed to maintain a confinement boundary between the processed waste and the operator. Operations that take placemore » inside the HHE include raising and lowering the hearth using a hydraulic lift table, transporting the hearth within the HHE using an overhead monorail and hoist system, sampling and disassembly of the processed waste and hearth, weighing the hearth, rebuilding a hearth, and sampling HEPA filters. The PHP radioactive bench-scale system is located at the TREAT facility at Argonne National Laboratory-West in Idaho Falls, Idaho.« less

Adaptive Estimation of Multiple Fading Factors for GPS/INS Integrated Navigation Systems.

PubMed

Jiang, Chen; Zhang, Shu-Bi; Zhang, Qiu-Zhao

2017-06-01

The Kalman filter has been widely applied in the field of dynamic navigation and positioning. However, its performance will be degraded in the presence of significant model errors and uncertain interferences. In the literature, the fading filter was proposed to control the influences of the model errors, and the H-infinity filter can be adopted to address the uncertainties by minimizing the estimation error in the worst case. In this paper, a new multiple fading factor, suitable for the Global Positioning System (GPS) and the Inertial Navigation System (INS) integrated navigation system, is proposed based on the optimization of the filter, and a comprehensive filtering algorithm is constructed by integrating the advantages of the H-infinity filter and the proposed multiple fading filter. Measurement data of the GPS/INS integrated navigation system are collected under actual conditions. Stability and robustness of the proposed filtering algorithm are tested with various experiments and contrastive analysis are performed with the measurement data. Results demonstrate that both the filter divergence and the influences of outliers are restrained effectively with the proposed filtering algorithm, and precision of the filtering results are improved simultaneously.

An approach for fixed coefficient RNS-based FIR filter

NASA Astrophysics Data System (ADS)

Srinivasa Reddy, Kotha; Sahoo, Subhendu Kumar

2017-08-01

In this work, an efficient new modular multiplication method for {2k-1, 2k, 2k+1-1} moduli set is proposed to implement a residue number system (RNS)-based fixed coefficient finite impulse response filter. The new multiplication approach reduces the number of partial products by using pre-loaded product block. The reduction in partial products with the proposed modular multiplication improves the clock frequency and reduces the area and power as compared with the conventional modular multiplication. Further, the present approach eliminates a binary number to residue number converter circuit, which is usually needed at the front end of RNS-based system. In this work, two fixed coefficient filter architectures with the new modular multiplication approach are proposed. The filters are implemented using Verilog hardware description language. The United Microelectronics Corporation 90 nm technology library has been used for synthesis and the results area, power and delay are obtained with the help of Cadence register transfer level compiler. The power delay product (PDP) is also considered for performance comparison among the proposed filters. One of the proposed architecture is found to improve PDP gain by 60.83% as compared with the filter implemented with conventional modular multiplier. The filters functionality is validated with the help of Altera DSP Builder.

Effect of heat and moisture exchanger (HME) positioning on inspiratory gas humidification

PubMed Central

Inui, Daisuke; Oto, Jun; Nishimura, Masaji

2006-01-01

Background In mechanically ventilated patients, we investigated how positioning the heat and moisture exchanger (HME) at different places on the ventilator circuit affected inspiratory gas humidification. Methods Absolute humidity (AH) and temperature (TEMP) at the proximal end of endotracheal tube (ETT) were measured in ten mechanically ventilated patients. The HME was connected either directly proximal to the ETT (Site 1) or at before the circuit Y-piece (Site 2: distance from proximal end of ETT and Site 2 was about 19 cm) (Figure. 1). Two devices, Hygrobac S (Mallinckrodt Dar, Mirandola, Italy) and Thermovent HEPA (Smiths Medical International Ltd., Kent, UK) were tested. AH and TEMP were measured with a hygrometer (Moiscope, MERA Co., Ltd., Tokyo, Japan). Results Hygrobac S provided significantly higher AH and TEMP at both sites than Thermovent HEPA. Both Hygrobac S and with Thermovent HEPA provided significantly higher AH and TEMP when placed proximally to the ETT. Conclusion Although placement proximal to the ETT improved both AH and TEMP in both HMEs tested, one HME performed better in the distal position than the other HME in the proximal position. We conclude the both the type and placement of HME can make a significant difference in maintaining AH and TEMP during adult ventilation. PMID:16895607

Physical activity and other lifestyle behaviors in a Portuguese sample of adults: results from the Azorean Physical Activity and Health Study.

PubMed

Santos, Rute; Santos, Maria Paula; Ribeiro, José Carlos; Mota, Jorge

2009-11-01

The aims of this study were to describe physical activity (PA) prevalence and compare it with other countries and to investigate possible associations between PA and other lifestyle behaviors in Azorean adults. 9991 adults (5723 women), aged 37.8 +/- 9.5 years, of the 2004 Azorean Physical Activity and Health Study. IPAQ assessed PA. All other lifestyle behaviors (age, gender, education level, income, employment, marital status, number of children, meal frequency, sleep time, sitting time, body mass index and alcohol and tobacco consumptions) were also self-reported. 57.1% of the participants met current PA recommendations and 32.2% were categorized as Health Enhancing PA (HEPA). Women were less likely to achieve PA recommendations, as well as the HEPA level. In both genders, higher education level, employment status, higher income, and sitting for more than 3h/day were negative predictors of HEPA; and, having at least 5 meals/day was positive predictor for the same PA level. There is a significant proportion of Azoreans, particularly women, that does not do enough PA. Targeted programs for Azoreans aimed to increase PA levels should pay special attention on women, and consider a multifactorial approach, once several lifestyle behaviors seem to interact with PA levels, in this population.

Walking in the high-rise city: a Health Enhancement and Pedometer-determined Ambulatory (HEPA) program in Hong Kong

PubMed Central

Leung, Angela YM; Cheung, Mike KT; Tse, Michael A; Shum, Wai Chuen; Lancaster, BJ; Lam, Cindy LK

2014-01-01

Due to the lack of good infrastructure in the public estates, many older adults in urban areas are sedentary. The Health Enhancement and Pedometer-Determined Ambulatory (HEPA) program was developed to assist older adults with diabetes and/or hypertension to acquire walking exercise habits and to build social support, while engaged in regular physical activity. This study aimed to describe the HEPA program and to report changes in participants’ walking capacity and body strength after 10-week walking sessions. A pre- and postintervention design was used. Pedometers were used to measure the number of steps taken per day before and after the 10-week intervention. Upper and lower body strength, lower body flexibility, and quality of life were assessed. A total of 205 older adults completed the program and all health assessments. After the 10-week intervention, the average number of steps per day increased by 36%, from 6,591 to 8,934. Lower body strength, upper body strength, and aerobic fitness increased significantly after 10 weeks, along with improvement in the 12-item Short Form Health Survey (SF™-12) physical and mental health component summary scores. A social support network was built in the neighborhood, and the local environment was utilized to make walking possible and enjoyable. PMID:25170259

CD147 stimulates hepatoma cells escaping from immune surveillance of T cells by interaction with Cyclophilin A.

PubMed

Ren, Yi-Xin; Wang, Shu-Jing; Fan, Jian-Hui; Sun, Shi-Jie; Li, Xia; Padhiar, Arshad Ahmed; Zhang, Jia-Ning

2016-05-01

T cells play an important role in tumor immune surveillance. CD147 is a member of immunoglobulin superfamily present on the surface of many tumor cells and mediates malignant cell behaviors. Cyclophilin A (CypA) is an intracellular protein promoting inflammation when released from cells. CypA is a natural ligand for CD147. In this study, CD147 specific short hairpin RNAs (shRNA) were transfected into murine hepatocellular carcinoma Hepa1-6 cells to assess the effects of CD147 on hepatoma cells escaping from immune surveillance of T cells. We found extracellular CypA stimulated cell proliferation through CD147 by activating ERK1/2 signaling pathway. Downregulation of CD147 expression on Hepa1-6 cells significantly suppressed tumor progression in vivo, and decreased cell viability when co-cultured with T cells in vitro. Importantly, knockdown of CD147 on Hepa1-6 cells resulted in significantly increased T cells chemotaxis induced by CypA both in vivo and in vitro. These findings provide novel mechanisms how tumor cells escaping from immune surveillance of T cells. We provide a potential therapy for hepatocellular carcinoma by targeting CD147 or CD147-CypA interactions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Transfer functions of double- and multiple-cavity Fabry-Perot filters driven by Lorentzian sources.

PubMed

Marti, J; Capmany, J

1996-12-20

We derive expressions for the transfer functions of double- and multiple-cavity Fabry-Perot filters driven by laser sources with Lorentzian spectrum. These are of interest because of their applications in sensing and channel filtering in optical frequency-division multiplexing networks.

Transfer functions of double- and multiple-cavity Fabry Perot filters driven by Lorentzian sources

NASA Astrophysics Data System (ADS)

Marti, Javier; Capmany, Jose

1996-12-01

We derive expressions for the transfer functions of double- and multiple-cavity Fabry Perot filters driven by laser sources with Lorentzian spectrum. These are of interest because of their applications in sensing and channel filtering in optical frequency-division multiplexing networks.

THE EFFECT OF SAMe AND BETAINE ON HEPA 1-6, C34 AND E47 LIVER CELL SURVIVAL IN VITRO

PubMed Central

Oliva, Joan; Zhong, Jin; Buslon, Virgil S.; French, Samuel W.

2011-01-01

In recent years, methyl one-carbon metabolism has received a great deal of attention because the disruption of methyl balance in a variety of genetically modified mice is associated with the development of various forms of liver injury, namely fatty liverdisease and hepatocellular carcinoma (HCC). In addition, patients with liver disease often have an abnormal expression of key genes involved in methionine metabolism as well as elevated serum levels of methionine and homocysteine (Hcy). S-adenosylmethionine (SAMe) has rapidly moved from being a methyl donor to a key metabolite that regulates hepatocyte proliferation, necrosis and differentiation. Biosynthesis of SAMe occurs in all mammalian cells as the first step in methionine catabolism in a reaction catalyzed by methionine adenosyltransferase (MAT). Decreased hepatic SAMe biosynthesis is a consequence of numerous forms of chronic liver injury. In an animal model of chronic liver SAMe deficiency, the liver is predisposed to further injury and develops spontaneous steatohepatitis and HCC. SAMe treatment in experimental animal models of liver injury shows that its hepatoprotective properties. Meta-analyses also showed that it is effective in the treatment of patients with cholestatic liver diseases. We studied the survival of liver cells treated with SAMe and betaine using Hepa 1–6 and E47/C34 cell lines. We showed that exogenous SAMe decreased the number of Hepa 1–6 and E47/C34 cells, and increased the number of dead cells in vitro. Betaine had no significant effect on the number of surviving cells and the number of dead cells. The combination of both methyl donors significantly increased the survival of liver cells and reduced necrosis, compare to SAMe alone. This study showed the inhibition of the proliferatino and increased necrosis in response to SAMe on liver cancer cell lines Hepa 1–6 and C34. PMID:22032937

PPAR agonists reduce steatosis in oleic acid-overloaded HepaRG cells

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

Rogue, Alexandra; Université de Rennes 1, Faculté des Sciences Pharmaceutiques et Biologiques, 35043 Rennes Cedex; Biologie Servier, Gidy

2014-04-01

Although non-alcoholic fatty liver disease (NAFLD) is currently the most common form of chronic liver disease there is no pharmacological agent approved for its treatment. Since peroxisome proliferator-activated receptors (PPARs) are closely associated with hepatic lipid metabolism, they seem to play important roles in NAFLD. However, the effects of PPAR agonists on steatosis that is a common pathology associated with NAFLD, remain largely controversial. In this study, the effects of various PPAR agonists, i.e. fenofibrate, bezafibrate, troglitazone, rosiglitazone, muraglitazar and tesaglitazar on oleic acid-induced steatotic HepaRG cells were investigated after a single 24-hour or 2-week repeat treatment. Lipid vesicles stainedmore » by Oil-Red O and triglycerides accumulation caused by oleic acid overload, were decreased, by up to 50%, while fatty acid oxidation was induced after 2-week co-treatment with PPAR agonists. The greatest effects on reduction of steatosis were obtained with the dual PPARα/γ agonist muraglitazar. Such improvement of steatosis was associated with up-regulation of genes related to fatty acid oxidation activity and down-regulation of many genes involved in lipogenesis. Moreover, modulation of expression of some nuclear receptor genes, such as FXR, LXRα and CAR, which are potent actors in the control of lipogenesis, was observed and might explain repression of de novo lipogenesis. Conclusion: Altogether, our in vitro data on steatotic HepaRG cells treated with PPAR agonists correlated well with clinical investigations, bringing a proof of concept that drug-induced reversal of steatosis in human can be evaluated in in vitro before conducting long-term and costly in vivo studies in animals and patients. - Highlights: • There is no pharmacological agent approved for the treatment of NAFLD. • This study demonstrates that PPAR agonists can reduce fatty acid-induced steatosis. • Some nuclear receptors appear to be potent actors in the control of lipogenesis. • A proof of concept that reversal of steatosis can be evaluated in human HepaRG cells.« less

Cost-effectiveness analysis of catch-up hepatitis A vaccination among unvaccinated/partially-vaccinated children

PubMed Central

Hankin-Wei, Abigail; Rein, David B.; Hernandez-Romieu, Alfonso; Kennedy, Mallory J.; Bulkow, Lisa; Rosenberg, Eli; Trigg, Monica; Nelson, Noele P.

2017-01-01

Background Since 2006, the US Centers for Disease Control and Prevention has recommended hepatitis A (HepA) vaccination routinely for children aged 12–23 months to prevent hepatitis A virus (HAV) infection. However, a substantial proportion of US children are unvaccinated and susceptible to infection. We present results of economic modeling to assess whether a one-time catch-up HepA vaccination recommendation would be cost-effective. Methods We developed a Markov model of HAV infection that followed a single cohort from birth through death (birth to age 95 years). The model compared the health and economic outcomes from catch-up vaccination interventions for children at target ages from two through 17 years vs. outcomes resulting from maintaining the current recommendation of routine vaccination at age one year with no catch-up intervention. Results Over the lifetime of the cohort, catch-up vaccination would reduce the total number of infections relative to the baseline by 741 while increasing doses of vaccine by 556,989. Catch-up vaccination would increase net costs by $10.2 million, or $2.38 per person. The incremental cost of HepA vaccine catch-up intervention at age 10 years, the midpoint of the ages modeled, was $452,239 per QALY gained. Across age-cohorts, the cost-effectiveness of catch-up vaccination is most favorable at age 12 years, resulting in an Incremental Cost-Effectiveness Ratio of $189,000 per QALY gained. Conclusions Given the low baseline of HAV disease incidence achieved by current vaccination recommendations, our economic model suggests that a catch-up vaccination recommendation would be less cost-effective than many other vaccine interventions, and that HepA catch-up vaccination would become cost effective at a threshold of $50,000 per QALY only when incidence of HAV rises about 5.0 cases per 100,000 population. PMID:27317459

Cost-effectiveness analysis of catch-up hepatitis A vaccination among unvaccinated/partially-vaccinated children.

PubMed

Hankin-Wei, Abigail; Rein, David B; Hernandez-Romieu, Alfonso; Kennedy, Mallory J; Bulkow, Lisa; Rosenberg, Eli; Trigg, Monica; Nelson, Noele P

2016-07-29

Since 2006, the US Centers for Disease Control and Prevention has recommended hepatitis A (HepA) vaccination routinely for children aged 12-23months to prevent hepatitis A virus (HAV) infection. However, a substantial proportion of US children are unvaccinated and susceptible to infection. We present results of economic modeling to assess whether a one-time catch-up HepA vaccination recommendation would be cost-effective. We developed a Markov model of HAV infection that followed a single cohort from birth through death (birth to age 95years). The model compared the health and economic outcomes from catch-up vaccination interventions for children at target ages from two through 17years vs. outcomes resulting from maintaining the current recommendation of routine vaccination at age one year with no catch-up intervention. Over the lifetime of the cohort, catch-up vaccination would reduce the total number of infections relative to the baseline by 741 while increasing doses of vaccine by 556,989. Catch-up vaccination would increase net costs by $10.2million, or $2.38 per person. The incremental cost of HepA vaccine catch-up intervention at age 10years, the midpoint of the ages modeled, was $452,239 per QALY gained. Across age-cohorts, the cost-effectiveness of catch-up vaccination is most favorable at age 12years, resulting in an Incremental Cost-Effectiveness Ratio of $189,000 per QALY gained. Given the low baseline of HAV disease incidence achieved by current vaccination recommendations, our economic model suggests that a catch-up vaccination recommendation would be less cost-effective than many other vaccine interventions, and that HepA catch-up vaccination would become cost effective at a threshold of $50,000 per QALY only when incidence of HAV rises about 5.0 cases per 100,000 population. Copyright © 2016 Elsevier Ltd. All rights reserved.

Introducing passive acoustic filter in acoustic based condition monitoring: Motor bike piston-bore fault identification

NASA Astrophysics Data System (ADS)

Jena, D. P.; Panigrahi, S. N.

2016-03-01

Requirement of designing a sophisticated digital band-pass filter in acoustic based condition monitoring has been eliminated by introducing a passive acoustic filter in the present work. So far, no one has attempted to explore the possibility of implementing passive acoustic filters in acoustic based condition monitoring as a pre-conditioner. In order to enhance the acoustic based condition monitoring, a passive acoustic band-pass filter has been designed and deployed. Towards achieving an efficient band-pass acoustic filter, a generalized design methodology has been proposed to design and optimize the desired acoustic filter using multiple filter components in series. An appropriate objective function has been identified for genetic algorithm (GA) based optimization technique with multiple design constraints. In addition, the sturdiness of the proposed method has been demonstrated in designing a band-pass filter by using an n-branch Quincke tube, a high pass filter and multiple Helmholtz resonators. The performance of the designed acoustic band-pass filter has been shown by investigating the piston-bore defect of a motor-bike using engine noise signature. On the introducing a passive acoustic filter in acoustic based condition monitoring reveals the enhancement in machine learning based fault identification practice significantly. This is also a first attempt of its own kind.

Self-reported hepatitis A vaccination as a predictor of hepatitis A virus antibody protection in U.S. adults: National Health and Nutrition Examination Survey 2007–2012

PubMed Central

Denniston, Maxine M.; Klevens, R. Monina; Jiles, Ruth B.; Murphy, Trudy V.

2015-01-01

Objectives To estimate the predictive value of self-reported hepatitis A vaccine (HepA) receipt for the presence of hepatitis A virus (HAV) antibody (anti-HAV) from either past infection or vaccination, as an indicator of HAV protection. Methods Using 2007–2012 National Health and Nutrition Examination Survey data, we assigned participants to 4 groups based on self-reported HepA receipt and anti-HAV results. We compared characteristics across groups and calculated three measures of agreement between self-report and serologic status (anti- HAV): percentage concordance, and positive (PPV) and negative (NPV) predictive values. Using logistic regression we investigated factors associated with agreement between self-reported vaccination status and serological results. Results Demographic and other characteristics varied significantly across the 4 groups. Overall agreement between self-reported HepA receipt and serological results was 63.6% (95% confidence interval [CI] 61.9–65.2); PPV and NPV of self-reported vaccination status for serological result were 47.0% (95% CI 44.2–49.8) and 69.4% (95% CI 67.0–71.8), respectively. Mexican American and foreign-born adults had the highest PPVs (71.5% [95% CI 65.9–76.5], and 75.8% [95% CI 71.4–79.7]) and the lowest NPVs (21.8% [95% CI 18.5–25.4], and 20.0% [95% CI 17.2–23.1]), respectively. Young (ages 20–29 years), US-born, and non-Hispanic White adults had the lowest PPVs (37.9% [95% CI 34.5–41.5], 39.1% [95% CI, 36.0–42.3], and 39.8% [36.1–43.7]), and the highest NPVs (76.9% [95% CI 72.2–81.0, 78.5% [95% CI 76.5–80.4)], and 80.6% [95% CI 78.2–82.8), respectively. Multivariate logistic analyses found age, race/ethnicity, education, place of birth and income to be significantly associated with agreement between self-reported vaccination status and serological results. Conclusions When assessing hepatitis A protection, self-report of not having received HepA was most likely to identify persons at risk for hepatitis A infection (no anti-HAV) among young, US-born and non-Hispanic White adults, and self-report of HepA receipt was least likely to be reliable among adults with the same characteristics. PMID:26116252

Multiple stage multiple filter hydrate store

DOEpatents

Bjorkman, H.K. Jr.

1983-05-31

An improved hydrate store for a metal halogen battery system is disclosed which employs a multiple stage, multiple filter means for separating the halogen hydrate from the liquid used in forming the hydrate. The filter means is constructed in the form of three separate sections which combine to substantially cover the interior surface of the store container. Exit conduit means is provided in association with the filter means for transmitting liquid passing through the filter means to a hydrate former subsystem. The hydrate former subsystem combines the halogen gas generated during the charging of the battery system with the liquid to form the hydrate in association with the store. Relief valve means is interposed in the exit conduit means for controlling the operation of the separate sections of the filter means, such that the liquid flow through the exit conduit means from each of the separate sections is controlled in a predetermined sequence. The three separate sections of the filter means operate in three discrete stages to provide a substantially uniform liquid flow to the hydrate former subsystem during the charging of the battery system. The separation of the liquid from the hydrate causes an increase in the density of the hydrate by concentrating the hydrate along the filter means. 7 figs.

Multiple stage multiple filter hydrate store

DOEpatents

Bjorkman, Jr., Harry K.

1983-05-31

An improved hydrate store for a metal halogen battery system is disclosed which employs a multiple stage, multiple filter means or separating the halogen hydrate from the liquid used in forming the hydrate. The filter means is constructed in the form of three separate sections which combine to substantially cover the interior surface of the store container. Exit conduit means is provided in association with the filter means for transmitting liquid passing through the filter means to a hydrate former subsystem. The hydrate former subsystem combines the halogen gas generated during the charging of the battery system with the liquid to form the hydrate in association with the store. Relief valve means is interposed in the exit conduit means for controlling the operation of the separate sections of the filter means, such that the liquid flow through the exit conduit means from each of the separate sections is controlled in a predetermined sequence. The three separate sections of the filter means operate in three discrete stages to provide a substantially uniform liquid flow to the hydrate former subsystem during the charging of the battery system. The separation of the liquid from the hydrate causes an increase in the density of the hydrate by concentrating the hydrate along the filter means.

Design of multi-wavelength tunable filter based on Lithium Niobate

NASA Astrophysics Data System (ADS)

Zhang, Ailing; Yao, Yuan; Zhang, Yue; Song, Hongyun

2018-05-01

A multi-wavelength tunable filter is designed. It consists of multiple waveguides among multiple waveguide gratings. A pair of electrodes were placed on both sides of each waveguide. The tunable filter uses the electro-optic effect of Lithium Niobate to tune the phase caused by each waveguide. Consequently, the wavelength and wavelength spacing of the filter are tuned by changing external voltages added on the electrode pairs. The tunable property of the filter is analyzed by phase matching condition and transfer-matrix method. Numerical results show that not only multiple wavelengths with narrow bandwidth are tuned with nearly equal spacing by synchronously changing the voltages added on all electrode pairs, but also the number of wavelengths is determined by the number of phase shifts caused by electrode pairs. Furthermore, due to the electro-optic effect of Lithium Niobate, the tuning speed of the filter can reach the order of ns.

Tunable high-channel-count bandstop graphene plasmonic filters based on plasmon induced transparency

NASA Astrophysics Data System (ADS)

Zhang, Zhengren; Long, Yang; Ma, Pengyu; Li, Hongqiang

2017-11-01

A high-channel-count bandstop graphene plasmonic filter based on ultracompact plasmonic structure is proposed in this paper. It consists of graphene waveguide side-coupled with a series of graphene filtering units. The study shows that the waveguide-resonator system performs a multiple plasmon induced transparency (PIT) phenomenon. By carefully adjusting the Fermi level of the filtering units, any two adjacent transmitted dips which belong to different PIT units can produce coherent coupling superposition enhancement. This property prevents the attenuation of the high-frequency transmission dips of multiple PIT and leads to an excellent bandstop filter with multiple channels. Specifically, the bandwidth and modulation depth of the filters can be flexibly adjusted by tuning the Fermi energy of the graphene waveguide. This ultracompact plasmonic structure contributes to the achievement of frequency division multiplexing systems for optical computing and communications in highly integrated optical circuits.

Differential BPFs with Multiple Transmission Zeros Based on Terminated Coupled Lines

NASA Astrophysics Data System (ADS)

Niu, Yiming; Yang, Guo; Wu, Wen

2018-04-01

Differential bandpass filters (BPFs) named Filter A and Filter B based on Terminated Coupled Lines (TCLs) are proposed in this letter. The TCLs contributes to not only three poles in differential-mode (DM) for wideband filtering response but also multiple zeros in both DM and common-mode (CM) offering wide DM out-of-band rejection and good CM suppression. Fabricated filters centred at 3.5 GHz with wide DM passband and wideband CM suppression have been designed and measured. The filters improved the noise suppression capability of the communication and radiometer systems. The simulated and measured results are in good agreement.

Quantum filtering for multiple diffusive and Poissonian measurements

NASA Astrophysics Data System (ADS)

Emzir, Muhammad F.; Woolley, Matthew J.; Petersen, Ian R.

2015-09-01

We provide a rigorous derivation of a quantum filter for the case of multiple measurements being made on a quantum system. We consider a class of measurement processes which are functions of bosonic field operators, including combinations of diffusive and Poissonian processes. This covers the standard cases from quantum optics, where homodyne detection may be described as a diffusive process and photon counting may be described as a Poissonian process. We obtain a necessary and sufficient condition for any pair of such measurements taken at different output channels to satisfy a commutation relationship. Then, we derive a general, multiple-measurement quantum filter as an extension of a single-measurement quantum filter. As an application we explicitly obtain the quantum filter corresponding to homodyne detection and photon counting at the output ports of a beam splitter.

Multiple model cardinalized probability hypothesis density filter

NASA Astrophysics Data System (ADS)

Georgescu, Ramona; Willett, Peter

2011-09-01

The Probability Hypothesis Density (PHD) filter propagates the first-moment approximation to the multi-target Bayesian posterior distribution while the Cardinalized PHD (CPHD) filter propagates both the posterior likelihood of (an unlabeled) target state and the posterior probability mass function of the number of targets. Extensions of the PHD filter to the multiple model (MM) framework have been published and were implemented either with a Sequential Monte Carlo or a Gaussian Mixture approach. In this work, we introduce the multiple model version of the more elaborate CPHD filter. We present the derivation of the prediction and update steps of the MMCPHD particularized for the case of two target motion models and proceed to show that in the case of a single model, the new MMCPHD equations reduce to the original CPHD equations.

Modified-hybrid optical neural network filter for multiple object recognition within cluttered scenes

NASA Astrophysics Data System (ADS)

Kypraios, Ioannis; Young, Rupert C. D.; Chatwin, Chris R.

2009-08-01

Motivated by the non-linear interpolation and generalization abilities of the hybrid optical neural network filter between the reference and non-reference images of the true-class object we designed the modifiedhybrid optical neural network filter. We applied an optical mask to the hybrid optical neural network's filter input. The mask was built with the constant weight connections of a randomly chosen image included in the training set. The resulted design of the modified-hybrid optical neural network filter is optimized for performing best in cluttered scenes of the true-class object. Due to the shift invariance properties inherited by its correlator unit the filter can accommodate multiple objects of the same class to be detected within an input cluttered image. Additionally, the architecture of the neural network unit of the general hybrid optical neural network filter allows the recognition of multiple objects of different classes within the input cluttered image by modifying the output layer of the unit. We test the modified-hybrid optical neural network filter for multiple objects of the same and of different classes' recognition within cluttered input images and video sequences of cluttered scenes. The filter is shown to exhibit with a single pass over the input data simultaneously out-of-plane rotation, shift invariance and good clutter tolerance. It is able to successfully detect and classify correctly the true-class objects within background clutter for which there has been no previous training.

Hepatic protection and anticancer activity of curcuma: a potential chemopreventive strategy against hepatocellular carcinoma.

PubMed

Li, Yan; Shi, Xue; Zhang, Jingwen; Zhang, Xiang; Martin, Robert C G

2014-02-01

Malignant transformation of hepatocellular carcinoma (HCC) occurs through repetitive liver injury in a context of inflammation and oxidative DNA damage. A spectrum of natural sesquiterpenoids from curcuma oil has displayed antioxidant, anti-inflammatory and anti-carcinogenic properties. The aim of the study was to investigate the hepatoprotective and anti-HCC effects of curcuma oil in vivo and in vitro. Mice were pretreated with curcuma oil (100 mg/kg) for 3 days, then treated with Concanavalin A (30 mg/kg). The hepatic tissue was evaluated for histology, CD4+ cell, interferon-γ, apoptosis, lipid peroxidation, 8-hydroxy-deoxyguanosine and MnSOD. C57L/J mice were treated with curcuma oil and 107 Hepa1-6 cells directly inoculated into liver lobes. The effects of curcuma oil on cell growth and cell death were evaluated. In addition, MnSOD, HSP60, catalase, NF-κB and caspase-3 were also investigated in the Hepa1-6 cells treated with curcuma oil. Pretreatment with curcuma oil significantly attenuates inflammation and oxidative damage by Concanavalin A. Treatment with curcuma oil can decrease the incidence of HCC. Curcuma oil inhibits cell growth and induces cell death in Hepa1-6 cells. Curcuma protected mice with hepatic injury from inflammatory and oxidative stress. Curcuma oil can inhibit hepatoma cell growth in vivo and in vitro.

Hepatic protection and anticancer activity of curcuma: A potential chemopreventive strategy against hepatocellular carcinoma

PubMed Central

LI, YAN; SHI, XUE; ZHANG, JINGWEN; ZHANG, XIANG; MARTIN, ROBERT C.G.

2014-01-01

Malignant transformation of hepatocellular carcinoma (HCC) occurs through repetitive liver injury in a context of inflammation and oxidative DNA damage. A spectrum of natural sesquiterpenoids from curcuma oil has displayed anti-oxidant, anti-inflammatory and anti-carcinogenic properties. The aim of the study was to investigate the hepatoprotective and anti-HCC effects of curcuma oil in vivo and in vitro. Mice were pretreated with curcuma oil (100 mg/kg) for 3 days, then treated with Concanavalin A (30 mg/kg). The hepatic tissue was evaluated for histology, CD4+ cell, interferon-γ, apoptosis, lipid peroxidation, 8-hydroxy-deoxyguanosine and MnSOD. C57L/J mice were treated with curcuma oil and 107 Hepa1-6 cells directly inoculated into liver lobes. The effects of curcuma oil on cell growth and cell death were evaluated. In addition, MnSOD, HSP60, catalase, NF-κB and caspase-3 were also investigated in the Hepa1-6 cells treated with curcuma oil. Pretreatment with curcuma oil significantly attenuates inflammation and oxidative damage by Concanavalin A. Treatment with curcuma oil can decrease the incidence of HCC. Curcuma oil inhibits cell growth and induces cell death in Hepa1-6 cells. Curcuma protected mice with hepatic injury from inflammatory and oxidative stress. Curcuma oil can inhibit hepatoma cell growth in vivo and in vitro. PMID:24270742

Multiple-hypothesis multiple-model line tracking

NASA Astrophysics Data System (ADS)

Pace, Donald W.; Owen, Mark W.; Cox, Henry

2000-07-01

Passive sonar signal processing generally includes tracking of narrowband and/or broadband signature components observed on a Lofargram or on a Bearing-Time-Record (BTR) display. Fielded line tracking approaches to date have been recursive and single-hypthesis-oriented Kalman- or alpha-beta filters, with no mechanism for considering tracking alternatives beyond the most recent scan of measurements. While adaptivity is often built into the filter to handle changing track dynamics, these approaches are still extensions of single target tracking solutions to multiple target tracking environment. This paper describes an application of multiple-hypothesis, multiple target tracking technology to the sonar line tracking problem. A Multiple Hypothesis Line Tracker (MHLT) is developed which retains the recursive minimum-mean-square-error tracking behavior of a Kalman Filter in a maximum-a-posteriori delayed-decision multiple hypothesis context. Multiple line track filter states are developed and maintained using the interacting multiple model (IMM) state representation. Further, the data association and assignment problem is enhanced by considering line attribute information (line bandwidth and SNR) in addition to beam/bearing and frequency fit. MHLT results on real sonar data are presented to demonstrate the benefits of the multiple hypothesis approach. The utility of the system in cluttered environments and particularly in crossing line situations is shown.

Strategies for the prevention of a successful biological warfare aerosol attack.

PubMed

Wiener, S L

1996-05-01

Biological warfare (BW) aerosol attacks are different from chemical attacks in that they may provide no warning/all clear signals that allow the soldier to put on or remove his M17/M40 protective mask. Methods are now being perfected to detect a BW aerosol cloud using an airborne (helicopter) pulsed laser system to scan the lower altitudes upwind from a troop concentration of corps size, and to sample and analyze the nature of the aerosol within a brief time interval. This system has certain limitations and vulnerabilities, since it is designed specifically to detect a line-type aerosol attack. Provision of, training with, and field use of a lightweight dust mist or HEPA filter respirator for each soldier is proposed for protection against undetected aerosol attacks. This particulate filter respirator would be issued in addition to the M17/M40 mask. Such a BW respirator will be able to purify the soldier's air by removing particles in the 0.3- to 15-micro m-diameter range with an efficiency of 98 to 100%. Particle size of BW aerosols is in the same range, with an optimum size for high-efficiency casualty production of 1 to 5 micro m mass median diameter. The proposed BW respirator will be lightweight; will require low inhalation pressures; will be comfortable to wear for prolonged periods; will not interfere with vision, hearing, and communication; and will not degrade overall effectiveness and performance to the degree observed with the M17/M40 masks. Such respirators would be worn as part of a contingency defense against an enemy likely to use BW agents. This respirator could be worn for prolonged periods when under threat of an undetectable BW attack during weather conditions favorable to the success of such an attack (i.e., low wind velocity and temperature inversion in the target area). In addition, tactically important assets such as command and control centers and missile batteries can also be protected continuously by air filtration systems powered by electricity (modular collective protection equipment). Vaccinations against anthrax, botulism, Q fever, plague, and tularemia are now available and immune protection against ricin and staphylococcal toxins appears feasible in the near future. Chemotherapy can also be provided for prophylaxis of infectious agents released on the battlefield. The vaccines and antibiotics can provide back-up protection against an unexpected BW attack during a period when the BW respirator is not in use or malfunctions due to a poor seal or filter leak. Enemy sites of biological weapon production, assembly, testing, and storage, and delivery vehicles can be targeted for destruction by bombs and/or missiles. An integrated, well-planned, BW defense with multiple components can decrease the likelihood of a successful enemy BW aerosol attack.

Effects on the efficiency of activated carbon on exposure to welding fumes

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

Ghosh, D.

1995-02-01

It is the intention of this paper to document that certain types of welding fumes have little or no effect on the effectiveness of the carbon filter air filtration efficiency when directly exposed to a controlled amount of welding fumes for a short-term period. The welding processes studied were restricted to shielded metal arc welding (SMAW), flux cored arc welding (FCAW), gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW) processes. Contrary to the SMAW and FCAW processes, the GTAW (or TIG) and the GMAW (or MIG) welding processes do not require the use of flux as partmore » of the overall process. Credit was taken for these processes occurring in inert gas environments and producing minimal amount of smoke. It was concluded that a study involving the SMAW process would also envelop the effects of the TIG and MIG welding processes. The quantity of welding fumes generated during the arc welding process is a function of the particular process, the size and type of electrode, welding machine amperage, and operator proficiency. For this study, the amount of welding for specific testing was equated to the amount of welding normally conducted during plant unit outages. Different welding electrodes were also evaluated, and the subsequent testing was limited to an E7018 electrode which was judged to be representative of all carbon and stainless steel electrodes commonly used at the site. The effect of welding fumes on activated charcoal was tested using a filtration unit complete with prefilters, upstream and downstream high efficiency particulate air (HEPA) filters, and a carbon adsorber section. The complete system was field tested in accordance with ANSI N510 standards prior to exposing the filters and the adsorber bed to welding fumes. The carbon samples were tested at an established laboratory using ASTM D3803-1989 standards.« less

A regularization of the Burgers equation using a filtered convective velocity

NASA Astrophysics Data System (ADS)

Norgard, Greg; Mohseni, Kamran

2008-08-01

This paper examines the properties of a regularization of the Burgers equation in one and multiple dimensions using a filtered convective velocity, which we have dubbed as the convectively filtered Burgers (CFB) equation. A physical motivation behind the filtering technique is presented. An existence and uniqueness theorem for multiple dimensions and a general class of filters is proven. Multiple invariants of motion are found for the CFB equation which are shown to be shared with the viscous and inviscid Burgers equations. Traveling wave solutions are found for a general class of filters and are shown to converge to weak solutions of the inviscid Burgers equation with the correct wave speed. Numerical simulations are conducted in 1D and 2D cases where the shock behavior, shock thickness and kinetic energy decay are examined. Energy spectra are also examined and are shown to be related to the smoothness of the solutions. This approach is presented with the hope of being extended to shock regularization of compressible Euler equations.

Sporting programs for inactive population groups: factors influencing implementation in the organized sports setting.

PubMed

Ooms, Linda; Veenhof, Cindy; Schipper-van Veldhoven, Nicolette; de Bakker, Dinny H

2015-01-01

The organized sports sector has received increased attention as a setting to promote health-enhancing physical activity (HEPA) to the general population. For significant public health impact, it is important that successful HEPA programs are widely adopted, implemented and continued as ongoing practice. The importance of evaluating the context in which programs are implemented has been identified as critical. However, little research has focused on understanding the organized sports implementation context, including factors facilitating and impeding implementation. In this study, the main factors influencing implementation of HEPA programs in the organized sports setting were studied. Fourteen sporting programs in the Netherlands aimed at increasing participation in sports by inactive population groups and funded within the National Action Plan for Sport and Exercise (NAPSE) were investigated. The programs were developed by ten Dutch National Sports Federations (NSFs) and implemented by different sports clubs in the Netherlands over a 3-year implementation period (June 2008-June 2011). The qualitative research component involved yearly face-to-face interviews (i.e. fourteen interviews each year, n = 12 program coordinators) and a group meeting with the program coordinators of the NSFs (n = 8). Cross-case comparisons and thematic analyses were performed to identify and categorize important facilitating and impeding factors respectively. The quantitative research component, used to identify the most important facilitating and impeding factors across all sporting programs, consisted of ranking of factors according to importance by the program coordinators (n = 12). Different factors act during six identified (implementation) phases. When comparing factors across phases, several key learnings were evident. Successful implementation relied, for example, on program design and enthusiastic individuals within sporting organizations. On the other hand, inactive people were hard to reach and participation of sports clubs was not self-evident. The findings were discussed in a broader context. This study adds to the knowledge base concerning the implementation of sporting programs, aimed at inactive people, in the organized sports setting. The main factors facilitating and impeding implementation were identified. The results of this study can be used by sports practitioners and policy makers when developing and implementing HEPA programs in this setting.

A Transcriptional Regulatory Network Containing Nuclear Receptors and Long Noncoding RNAs Controls Basal and Drug-Induced Expression of Cytochrome P450s in HepaRG Cells.

PubMed

Chen, Liming; Bao, Yifan; Piekos, Stephanie C; Zhu, Kexin; Zhang, Lirong; Zhong, Xiao-Bo

2018-07-01

Cytochrome P450 (P450) enzymes are responsible for metabolizing drugs. Expression of P450s can directly affect drug metabolism, resulting in various outcomes in therapeutic efficacy and adverse effects. Several nuclear receptors are transcription factors that can regulate expression of P450s at both basal and drug-induced levels. Some long noncoding RNAs (lncRNAs) near a transcription factor are found to participate in the regulatory functions of the transcription factors. The aim of this study is to determine whether there is a transcriptional regulatory network containing nuclear receptors and lncRNAs controlling both basal and drug-induced expression of P450s in HepaRG cells. Small interfering RNAs or small hairpin RNAs were applied to knock down four nuclear receptors [hepatocyte nuclear factor 1 α (HNF1 α ), hepatocyte nuclear factor 4 α (HNF4 α ), pregnane X receptor (PXR), and constitutive androstane receptor (CAR)] as well as two lncRNAs [HNF1 α antisense RNA 1 (HNF1 α -AS1) and HNF4 α antisense RNA 1 (HNF4 α -AS1)] in HepaRG cells with or without treatment of phenobarbital or rifampicin. Expression of eight P450 enzymes was examined in both basal and drug-induced levels. CAR and PXR mainly regulated expression of specific P450s. HNF1 α and HNF4 α affected expression of a wide range of P450s as well as other transcription factors. HNF1 α and HNF4 α controlled the expression of their neighborhood lncRNAs, HNF1 α -AS1 and HNF4 α -AS1, respectively. HNF1 α -AS1 and HNF4 α -AS1 was also involved in the regulation of P450s and transcription factors in diverse manners. Altogether, our study concludes that a transcription regulatory network containing the nuclear receptors and lncRNAs controls both basal and drug-induced expression of P450s in HepaRG cells. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

Synergistic effect of interleukin-17 and tumour necrosis factor-α on inflammatory response in hepatocytes through interleukin-6-dependent and independent pathways.

PubMed

Beringer, A; Thiam, N; Molle, J; Bartosch, B; Miossec, P

2018-04-20

The proinflammatory cytokines interleukin (IL)-17 and tumour necrosis factor (TNF)-α are targets for treatment in many chronic inflammatory diseases. Here, we examined their role in liver inflammatory response compared to that of IL-6. Human hepatoma cells (HepaRG, Huh7.5 and HepG2 cells) and primary human hepatocytes (PHH) were cultured with IL-6, IL-17 and/or TNF-α. To determine the contribution of the IL-6 pathway in the IL-17/TNF-α-mediated effect, an anti-IL-6 receptor antibody was used. IL-17 and TNF-α increased in synergy IL-6 secretion by HepaRG cells and PHH but not by Huh7.5 and HepG2 cells. This IL-17/TNF-α synergistic cooperation enhanced the levels of C-reactive protein (CRP) and aspartate aminotransferase (ASAT) in HepaRG cell and PHH cultures through the induction of IL-6. IL-17/TNF-α also up-regulated IL-8, monocyte chemoattractant protein (MCP)-1 and chemokine (C-C motif) ligand 20 (CCL20) chemokines in synergy through an IL-6-independent pathway. Interestingly, first exposure to IL-17, but not to TNF-α, was crucial for the initiation of the IL-17/TNF-α synergistic effect on IL-6 and IL-8 production. In HepaRG cells, IL-17 enhanced IL-6 mRNA stability resulting in increased IL-6 protein levels. The IL-17A/TNF-α synergistic effect on IL-6 and IL-8 induction was mediated through the activation of extracellular signal-regulated kinase (ERK)-mitogen-activated protein kinase, nuclear factor-κB and/or protein kinase B (Akt)-phosphatidylinositol 3-kinase signalling pathways. Therefore, the IL-17/TNF-α synergistic interaction mediates systemic inflammation and cell damage in hepatocytes mainly through IL-6 for CRP and ASAT induction. Independently of IL-6, the IL-17A/TNF-α combination may also induce immune cell recruitment by chemokine up-regulation. IL-17 and/or TNF-α neutralization can be a promising therapeutic strategy to control both systemic inflammation and liver cell attraction. © 2018 British Society for Immunology.

Physical activity in adults with congenital heart disease and associations with functional outcomes.

PubMed

Müller, Jan; Amberger, Tamara; Berg, Anika; Goeder, Daniel; Remmele, Julia; Oberhoffer, Renate; Ewert, Peter; Hager, Alfred

2017-07-01

Improved survival has yielded to growing importance of functional outcome measures in patients with congenital heart disease (CHD). This study applied the International Physical Activity Questionnaire (IPAQ) to assess self-reported physical activity (PA) in patients with CHD and their association with exercise capacity and health-related quality of life (HrQoL). Prior to cardiopulmonary exercise testing (CPET), 786 consecutive patients (335 female, 31.1±11.6 years) with CHD filled in the short form of the IPAQ and the HrQoL questionnaire 36-Item Short Form. In total, 393 (50.0%) patients reported health-enhancing physical activity (HEPA), 237 (30.2%) minimal activity and 156 (19.8%) inactivity. In comparison with the HEPA group, the inactive group had significant lower peak oxygen uptake (74.2%±20.7% vs 86.8%±22.3%; p<0.001) as well as lower physical (91.0%±16.9% vs 97.4%±13.6%; p<0.001) and mental (97.1%±22.2% vs 104.1%±15.6%; p<0.001) HrQoL. Independent of severity class, surgery, age, beta-blocker, pacemaker and oxygen saturation, the HEPA group in comparison with the inactive group showed significantly less probability for impairments in mental (OR: 0.21, 95% CI: 0.10 to 0.45; p<0.001) and physical (OR: 0.46, 95% CI: 0.23 to 0.92; p=0.027) HrQoL and exercise capacity (OR: 0.36, 95% CI: 0.22 to 0.59; p<0.001). Categorisation of patientswith CHD with the IPAQ quickly provides clinical information as HEPA patients have a less probability for impaired HrQoL and diminished exercise capacity. Nevertheless, the IPAQ cannot substitute an accelerometer-based assessment for PA, nor a CPET for exercise capacity. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Logarithmic r-θ mapping for hybrid optical neural network filter for multiple objects recognition within cluttered scenes

NASA Astrophysics Data System (ADS)

Kypraios, Ioannis; Young, Rupert C. D.; Chatwin, Chris R.; Birch, Phil M.

2009-04-01

θThe window unit in the design of the complex logarithmic r-θ mapping for hybrid optical neural network filter can allow multiple objects of the same class to be detected within the input image. Additionally, the architecture of the neural network unit of the complex logarithmic r-θ mapping for hybrid optical neural network filter becomes attractive for accommodating the recognition of multiple objects of different classes within the input image by modifying the output layer of the unit. We test the overall filter for multiple objects of the same and of different classes' recognition within cluttered input images and video sequences of cluttered scenes. Logarithmic r-θ mapping for hybrid optical neural network filter is shown to exhibit with a single pass over the input data simultaneously in-plane rotation, out-of-plane rotation, scale, log r-θ map translation and shift invariance, and good clutter tolerance by recognizing correctly the different objects within the cluttered scenes. We record in our results additional extracted information from the cluttered scenes about the objects' relative position, scale and in-plane rotation.

The Ground-Based Transmission Spectrum of HD 189733b as Generated Through Multiple Broadband Filter Observations

NASA Astrophysics Data System (ADS)

Kasper, David; Cole, Jackson L.; Gardner, Cristilyn N.; Garver, Bethany; Jarka, Kyla L.; Kar, Aman; McGough, Aylin M.; PeQueen, David J.; Rivera, Daniel Ivan; Jang-Condell, Hannah; Kobulnicky, Henry A.; Dale, Daniel A.

2018-06-01

We present new multi-broadband transit photometry of HD 189733b observed with the Wyoming Infrared Observatory. With an ensemble of Sloan filter observations across multiple transits we have created an ultra-low resolution transmission spectrum to discern the nature of the exoplanet atmosphere. This data set exemplifies the capabilities of the 2.3 m observatory. The analysis was performed with a Markov-Chain Monte-Carlo method assisted by a Gaussian-processes regression model. These observations were taken as part of the University of Wyoming's 2017 Research Experience for Undergraduates (REU) and represent one of multiple hot Jupiter exoplanet targets for which we have transit event observations in multiple broadband filters.

Surgical practices in total knee arthroplasty in Turkey.

PubMed

Erduran, Mehmet; Akseki, Devrim; Araç, Sükrü

2012-01-01

The aim of this study was to determine the current practices in the total knee arthroplasty (TKA) and the differences of practice among the orthopedic surgeons in Turkey. Data in this cross-sectional and descriptive study was collected through a questionnaire from 76 orthopaedic surgeons performing TKA. The questionnaire form contained 57 questions under four main headings, covering the professional properties of the surgeon, pre-surgery approach, surgical technique applied for TKA and the surgical details peculiar to the technique with solutions applied for complication scenarios, and finally the postoperative approach. It was determined that 39.7% of the TKA applications were performed in operating theatres without laminar airflow or HEPA filters. Nearly 1/5 of the surgeons used more than one antibiotic for prophylaxis, and more than 85% continued prophylaxis use over 3 days. Low-molecular-weight heparin was the most commonly used method for thromboprophylaxis. 94.67% of the surgeons used only the cemented technique in primary TKA. 44% indicated that they performed simultaneous bilateral arthroplasty, 89% did not use any scoring system and 72.37% preferred fixed-bearing and posterior-cruciate-retaining type prosthesis. Results showed no standardization in TKA surgery among surgeons in Turkey, and important educational deficiencies were noted.

77 FR 48967 - Marine Mammals; File No. 17350

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-15

... permit has been issued to the North Slope Borough Department of Wildlife Management, P.O. Box 69, Barrow, AK 99723 [Taqulik Hepa, Responsible Party; Dr. John C. George, Principal Investigator] to collect...

77 FR 37000 - Marine Mammals; File No. 814-1899

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-20

... hereby given that the North Slope Borough Department of Wildlife Management, P.O. Box 69, Barrow, AK 99723 [Taqulik Hepa, Responsible Party; Dr. John C. George, Principal Investigator], has been issued a...

Metabolomics analysis of the toxicity pathways of triphenyl phosphate in HepaRG cells and comparison to oxidative stress mechanisms caused by acetaminophen.

PubMed

Van den Eede, Nele; Cuykx, Matthias; Rodrigues, Robim M; Laukens, Kris; Neels, Hugo; Covaci, Adrian; Vanhaecke, Tamara

2015-12-01

Since the publication of REACH guidelines, the need for in vitro tools for toxicity testing has increased. We present here the development of a hepatotoxicity testing tool using human HepaRG cell cultures and metabolomics. HepaRG cells were exposed to either 4mM acetaminophen (APAP) as reference toxicant for oxidative stress or 50 μM triphenyl phosphate (TPHP) as toxicant with unknown toxicity pathways (TPs). After 72 h exposure, cells were subjected to quenching and liquid-liquid extraction which resulted in a polar and an apolar fraction. Analysis of fractions was performed by ultrahigh performance liquid chromatography-high resolution tandem mass spectrometry (UHPLC-QTOF-MS). Significantly up or down regulated metabolites were selected by univariate statistics prior to identification. In order to obtain robust and specific TP biomarkers, the experiment was also repeated using a different culture medium composition to assess which metabolites show consistent changes. Potential biomarkers belonging to different TPs were found for APAP and TPHP. For APAP, the biomarkers were related to a decrease in unsaturated phospholipids, and for TPHP to an accumulation of phosphoglycerolipids and increase of palmitoyl lysophosphatidylcholine. This first proof-of-concept opens new perspectives for the analysis of other (reference) toxicants with different TPs and it can be used to expand the in vitro tool for hepatotoxicity screening of various compounds. Copyright © 2015 Elsevier B.V. All rights reserved.

The Chinese Herbal Medicine Sophora flavescens Activates Pregnane X Receptor

PubMed Central

Wang, Laiyou; Li, Feng; Lu, Jie; Li, Guodong; Li, Dan; Zhong, Xiao-bo; Guo, Grace L.

2010-01-01

Sophora flavescens (SF) is an herbal medicine widely used for the treatment of viral hepatitis, cancer, viral myocarditis, gastrointestinal hemorrhage, and skin diseases. It was recently reported that SF up-regulates CYP3A expression. The mechanism of SF-induced CYP3A expression is unknown. In the current study, we tested the hypothesis that SF-induced CYP3A expression is mediated by the activation of pregnane X receptor (PXR). We used two cell lines, DPX2 and HepaRG, to investigate the role of PXR in SF-induced CYP3A expression. The DPX2 cell line is derived from HepG2 cells with the stable transfection of human PXR and a luciferase reporter gene linked with a human PXR response element identified in the CYP3A4 gene promoter. In DPX2 cells, SF activated PXR in a concentration-dependent manner. We used a metabolomic approach to identify the chemical constituents in SF, which were further analyzed for their effect on PXR activation and CYP3A regulation. One chemical in SF, N-methylcytisine, was identified as an individual chemical that activated PXR. HepaRG is a highly differentiated hepatoma cell line that mimics human hepatocytes. In HepaRG cells, N-methylcytisine significantly induced CYP3A4 expression, and this induction was suppressed by the PXR antagonist sulforaphane. These results suggest that SF induces CYP3A expression via the activation of PXR. PMID:20736322

Multiple wavelengths filtering of light through inner resonances.

PubMed

Felbacq, Didier; Larciprete, Maria Cristina; Sibilia, Concita; Bertolotti, Mario; Scalora, Michael

2005-12-01

We show that by using the internal resonances of a grating, it is possible to design a filter working for multiple wavelengths. We study the characteristics of the device with respect to the constituting parameters and we propose a realization process.

Multiple feature extraction by using simultaneous wavelet transforms

NASA Astrophysics Data System (ADS)

Mazzaferri, Javier; Ledesma, Silvia; Iemmi, Claudio

2003-07-01

We propose here a method to optically perform multiple feature extraction by using wavelet transforms. The method is based on obtaining the optical correlation by means of a Vander Lugt architecture, where the scene and the filter are displayed on spatial light modulators (SLMs). Multiple phase filters containing the information about the features that we are interested in extracting are designed and then displayed on an SLM working in phase mostly mode. We have designed filters to simultaneously detect edges and corners or different characteristic frequencies contained in the input scene. Simulated and experimental results are shown.

Polarization-independent optical wavelength filter for channel dropping applications

DOEpatents

Deri, R.J.; Patterson, F.

1996-05-07

The polarization dependence of optical wavelength filters is eliminated by using waveguide directional couplers. Material birefringence is used to compensate for the waveguide (electromagnetic) birefringence which is the original cause of the polarization dependence. Material birefringence is introduced in a controllable fashion by replacing bulk waveguide layers by finely layered composites, such as multiple quantum wells using III-V semiconductor materials. The filter has use in wavelength-division multiplexed fiber optic communication systems. This filter has broad application for wavelength-tunable receivers in fiber optic communication links, which may be used for telecommunications, optical computer interconnect links, or fiber optic sensor systems. Since multiple-wavelength systems are increasingly being used for all of these applications, the filter is useable whenever a rapidly tunable, wavelength-filtering receiver is required. 14 figs.

Polarization-independent optical wavelength filter for channel dropping applications

DOEpatents

Deri, Robert J.; Patterson, Frank

1996-01-01

The polarization dependence of optical wavelength filters is eliminated by using waveguide directional couplers. Material birefringence is used to compensate for the waveguide (electromagnetic) birefringence which is the original cause of the polarization dependence. Material birefringence is introduced in a controllable fashion by replacing bulk waveguide layers by finely layered composites, such as multiple quantum wells using III-V semiconductor materials. The filter has use in wavelength-division-multiplexed fiber optic communication systems. This filter has broad application for wavelength-tunable receivers in fiber optic communication links, which may be used for telecommunications, optical computer interconnect links, or fiber optic sensor systems. Since multiple-wavelength systems are increasingly being used for all of these applications, the filter is useable whenever a rapidly tunable, wavelength-filtering receiver is required.

Labeled RFS-Based Track-Before-Detect for Multiple Maneuvering Targets in the Infrared Focal Plane Array.

PubMed

Li, Miao; Li, Jun; Zhou, Yiyu

2015-12-08

The problem of jointly detecting and tracking multiple targets from the raw observations of an infrared focal plane array is a challenging task, especially for the case with uncertain target dynamics. In this paper a multi-model labeled multi-Bernoulli (MM-LMB) track-before-detect method is proposed within the labeled random finite sets (RFS) framework. The proposed track-before-detect method consists of two parts-MM-LMB filter and MM-LMB smoother. For the MM-LMB filter, original LMB filter is applied to track-before-detect based on target and measurement models, and is integrated with the interacting multiple models (IMM) approach to accommodate the uncertainty of target dynamics. For the MM-LMB smoother, taking advantage of the track labels and posterior model transition probability, the single-model single-target smoother is extended to a multi-model multi-target smoother. A Sequential Monte Carlo approach is also presented to implement the proposed method. Simulation results show the proposed method can effectively achieve tracking continuity for multiple maneuvering targets. In addition, compared with the forward filtering alone, our method is more robust due to its combination of forward filtering and backward smoothing.

Labeled RFS-Based Track-Before-Detect for Multiple Maneuvering Targets in the Infrared Focal Plane Array

PubMed Central

Li, Miao; Li, Jun; Zhou, Yiyu

2015-01-01

The problem of jointly detecting and tracking multiple targets from the raw observations of an infrared focal plane array is a challenging task, especially for the case with uncertain target dynamics. In this paper a multi-model labeled multi-Bernoulli (MM-LMB) track-before-detect method is proposed within the labeled random finite sets (RFS) framework. The proposed track-before-detect method consists of two parts—MM-LMB filter and MM-LMB smoother. For the MM-LMB filter, original LMB filter is applied to track-before-detect based on target and measurement models, and is integrated with the interacting multiple models (IMM) approach to accommodate the uncertainty of target dynamics. For the MM-LMB smoother, taking advantage of the track labels and posterior model transition probability, the single-model single-target smoother is extended to a multi-model multi-target smoother. A Sequential Monte Carlo approach is also presented to implement the proposed method. Simulation results show the proposed method can effectively achieve tracking continuity for multiple maneuvering targets. In addition, compared with the forward filtering alone, our method is more robust due to its combination of forward filtering and backward smoothing. PMID:26670234

Filtering for networked control systems with single/multiple measurement packets subject to multiple-step measurement delays and multiple packet dropouts

NASA Astrophysics Data System (ADS)

Moayedi, Maryam; Foo, Yung Kuan; Chai Soh, Yeng

2011-03-01

The minimum-variance filtering problem in networked control systems, where both random measurement transmission delays and packet dropouts may occur, is investigated in this article. Instead of following the many existing results that solve the problem by using probabilistic approaches based on the probabilities of the uncertainties occurring between the sensor and the filter, we propose a non-probabilistic approach by time-stamping the measurement packets. Both single-measurement and multiple measurement packets are studied. We also consider the case of burst arrivals, where more than one packet may arrive between the receiver's previous and current sampling times; the scenario where the control input is non-zero and subject to delays and packet dropouts is examined as well. It is shown that, in such a situation, the optimal state estimate would generally be dependent on the possible control input. Simulations are presented to demonstrate the performance of the various proposed filters.

Tunable filters for multispectral imaging of aeronomical features

NASA Astrophysics Data System (ADS)

Goenka, C.; Semeter, J. L.; Noto, J.; Dahlgren, H.; Marshall, R.; Baumgardner, J.; Riccobono, J.; Migliozzi, M.

2013-10-01

Multispectral imaging of optical emissions in the Earth's upper atmosphere unravels vital information about dynamic phenomena in the Earth-space environment. Wavelength tunable filters allow us to accomplish this without using filter wheels or multiple imaging setups, but with identifiable caveats and trade-offs. We evaluate one such filter, a liquid crystal Fabry-Perot etalon, as a potential candidate for the next generation of imagers for aeronomy. The tunability of such a filter can be exploited in imaging features such as the 6300-6364 Å oxygen emission doublet, or studying the rotational temperature of N2+ in the 4200-4300 Å range, observations which typically require multiple instruments. We further discuss the use of this filter in an optical instrument, called the Liquid Crystal Hyperspectral Imager (LiCHI), which will be developed to make simultaneous measurements in various wavelength ranges.

Demodulation of moire fringes in digital holographic interferometry using an extended Kalman filter.

PubMed

Ramaiah, Jagadesh; Rastogi, Pramod; Rajshekhar, Gannavarpu

2018-03-10

This paper presents a method for extracting multiple phases from a single moire fringe pattern in digital holographic interferometry. The method relies on component separation using singular value decomposition and an extended Kalman filter for demodulating the moire fringes. The Kalman filter is applied by modeling the interference field locally as a multi-component polynomial phase signal and extracting the associated multiple polynomial coefficients using the state space approach. In addition to phase, the corresponding multiple phase derivatives can be simultaneously extracted using the proposed method. The applicability of the proposed method is demonstrated using simulation and experimental results.

Ultrasound image filtering using the mutiplicative model

NASA Astrophysics Data System (ADS)

Navarrete, Hugo; Frery, Alejandro C.; Sanchez, Fermin; Anto, Joan

2002-04-01

Ultrasound images, as a special case of coherent images, are normally corrupted with multiplicative noise i.e. speckle noise. Speckle noise reduction is a difficult task due to its multiplicative nature, but good statistical models of speckle formation are useful to design adaptive speckle reduction filters. In this article a new statistical model, emerging from the Multiplicative Model framework, is presented and compared to previous models (Rayleigh, Rice and K laws). It is shown that the proposed model gives the best performance when modeling the statistics of ultrasound images. Finally, the parameters of the model can be used to quantify the extent of speckle formation; this quantification is applied to adaptive speckle reduction filter design. The effectiveness of the filter is demonstrated on typical in-vivo log-compressed B-scan images obtained by a clinical ultrasound system.

Vaccinations for Adults with Hepatitis C Infection

MedlinePlus

... up to date. Vaccine Do you need it? Hepatitis A (HepA) Yes! Your chronic liver disease puts you ... serious complications if you get infected with the hepatitis A virus. If you’ve never been vaccinated against ...

Vaccinations for Preteens and Teens, Age 11-19 Years

MedlinePlus

... Vaccine Do you need it? Chickenpox (varicella; Var) Yes! If you haven’t been vaccinated and haven’ ... should get a second dose. Hepatitis A (HepA) Yes! You need 2 doses of hepatitis A vaccine ...

Günther Tulip and Celect IVC filters in multiple-trauma patients.

PubMed

Rosenthal, David; Kochupura, Paul V; Wellons, Eric D; Burkett, Allison B; Methodius-Rayford, Walaya C

2009-08-01

To evaluate results with the retrievable Günther Tulip (GT) and Celect inferior vena cava filters (IVCFs) placed at the intensive care unit (ICU) bedside under "real-time" intravascular ultrasound (IVUS) guidance in multiple-trauma patients. Between December 2004 and December 2008, 187 multiple-trauma patients (109 men; mean age 44+/-2 years, range 17-71) with contraindications to low-dose anticoagulation therapy or sequential compression devices had Günther Tulip (n = 97) or Celect (n = 90) retrievable IVCFs placed under real-time IVUS guidance. Günther Tulip filters were inserted using a "double-puncture" technique. The Celect IVCFs were placed with a simplified single-puncture technique in which the filter introducer sheath was advanced until the radiopaque tip "covered" the IVUS image of the renal vein, indicating that the filter sheath was in position for filter deployment. The 2 filter groups were compared on the endpoints of technical implantation success, retrievability, prevention of PE, and procedure-related deep vein thrombosis (DVT). As verified by abdominal radiography, 93.1% (174/187) of IVCFs were placed without complications; 6 IVCFs (all GT; p = 0.03 versus Celect) were misplaced in the iliac vein but uneventfully retrieved and replaced in the IVC within 24 hours. Two insertion site femoral vein DVTs (both in the dual puncture group; p>0.2) and 5 groin hematomas occurred during follow-up. GT filters were in place a mean of 107 days and Celect 97 days. In this time, 2 pulmonary embolisms occurred (1 in each group; p>0.2). Of the 115 filters scheduled for retrieval (50 Günther Tulip, 65 Celect), 33 (23 Günther Tulip, 10 Celect) could not be retrieved (p = 0.0004). Vena cavography identified filter tilting (>20 degrees ) in 21 cases (15 GT, 6 Celect), while 12 filters (8 GT, 4 Celect) had extended indwell times (mean 187 days) and excessive tissue ingrowth covering the retrieval hook. Subjectively, the Celect filters were clinically "easier" to retrieve; they also had fewer cases of significant tilt (>20%) than the GT filters, but the difference was not statistically significant. GT and Celect IVCFs placed at the ICU bedside under IVUS guidance in multiple-trauma patients was simple, safe, and avoided transporting critically ill patients out of the ICU. Further investigation of the single sheath IVUS technique and the role of retrievable IVCFs in multi-trauma patients is warranted.

Combating speckle in SAR images - Vector filtering and sequential classification based on a multiplicative noise model

NASA Technical Reports Server (NTRS)

Lin, Qian; Allebach, Jan P.

1990-01-01

An adaptive vector linear minimum mean-squared error (LMMSE) filter for multichannel images with multiplicative noise is presented. It is shown theoretically that the mean-squared error in the filter output is reduced by making use of the correlation between image bands. The vector and conventional scalar LMMSE filters are applied to a three-band SIR-B SAR, and their performance is compared. Based on a mutliplicative noise model, the per-pel maximum likelihood classifier was derived. The authors extend this to the design of sequential and robust classifiers. These classifiers are also applied to the three-band SIR-B SAR image.

Implementation of a Parameterized Interacting Multiple Model Filter on an FPGA for Satellite Communications

NASA Technical Reports Server (NTRS)

Hackett, Timothy M.; Bilen, Sven G.; Ferreira, Paulo Victor R.; Wyglinski, Alexander M.; Reinhart, Richard C.

2016-01-01

In a communications channel, the space environment between a spacecraft and an Earth ground station can potentially cause the loss of a data link or at least degrade its performance due to atmospheric effects, shadowing, multipath, or other impairments. In adaptive and coded modulation, the signal power level at the receiver can be used in order to choose a modulation-coding technique that maximizes throughput while meeting bit error rate (BER) and other performance requirements. It is the goal of this research to implement a generalized interacting multiple model (IMM) filter based on Kalman filters for improved received power estimation on software-dened radio (SDR) technology for satellite communications applications. The IMM filter has been implemented in Verilog consisting of a customizable bank of Kalman filters for choosing between performance and resource utilization. Each Kalman filter can be implemented using either solely a Schur complement module (for high area efficiency) or with Schur complement, matrix multiplication, and matrix addition modules (for high performance). These modules were simulated and synthesized for the Virtex II platform on the JPL Radio Experimenter Development System (EDS) at NASA Glenn Research Center. The results for simulation, synthesis, and hardware testing are presented.

The effect of high-efficiency particulate air respirator design on occupational health: a pilot study balancing risks in the real world.

PubMed

Eck, E K; Vannier, A

1997-02-01

To quantify specific factors believed to increase healthcare worker (HCW) risk for contaminated sharps injuries (eg, visibility, communication, and range of motion); to quantify the degree to which respirators of various designs impacted those same factors; and to assess HCW opinions about the suitability of selected respirators with respect to patient care and user compliance criteria. Sharps injury data from seven hospitals were analyzed to determine the potential contribution of visibility, communication, and range of motion to reported injuries. Healthcare workers representing various clinical specialties and physical characteristics were examined at baseline and while wearing five different respirators to quantify the impact of respirator design on visibility, communication, and range of motion. Healthcare workers were interviewed and completed a survey assessing each respirator. Hospital and ambulatory-care settings. Population-based and convenience sample. Communication, visibility, and range of motion were found to affect contaminated sharps injuries significantly. Selected high-efficiency particulate air (HEPA) respirators were found to have a negative impact on each of these variables. Healthcare workers involved in the study also reported compliance criteria problems with selected HEPA respirators, which may effect implementation of respiratory precautions adversely. Current HEPA respirators, because of their design, potentially increase the risk of bloodborne pathogen exposure through sharps injuries. We conclude that mandating respirators without regard to the potential impact of their design to the sharps injuries may be counterproductive to HCW safety, because they may increase, rather than decrease, overall occupational risk to HCWs.

Effect of methapyrilene hydrochloride on hepatic intracellular iron metabolism in vivo and in vitro.

PubMed

Kindrat, Iryna; Dreval, Kostiantyn; Shpyleva, Svitlana; Tryndyak, Volodymyr; de Conti, Aline; Mudalige, Thilak K; Chen, Tao; Erstenyuk, Anna M; Beland, Frederick A; Pogribny, Igor P

2017-11-05

The liver, a central detoxification organ and main regulator of systemic iron homeostasis, is prone to damage by xenobiotics. In the present study, we investigated the effect of the hepatotoxicant and hepatocarcinogen methapyrilene hydrochloride on iron metabolism in rat liver in a repeat-dose in vivo toxicity study and in human HepaRG cells in vitro. Treatment of male Fischer 344 (F344) rats with methapyrilene at doses 40 and 80mg/kg body weight (bw)/day by gavage for 6 weeks resulted in changes in the expression of classic hepatotoxicity-related marker genes and iron homeostasis-related genes, especially a prominent, dose-dependent down-regulation of the transferrin (Tf) gene and an up-regulation of the ferritin, light chain (Ftl) gene. A decrease in the level of TF and an increase in the level of FTL also occurred in methapyrilene-treated differentiated HepaRG cells, indicating the existence of interspecies and in vitro-in vivo similarities in the disturbance of cellular iron homeostasis upon liver injury. In contrast, there was minimal overlap in the expression of liver toxicity-marker genes in the livers of rats and in HepaRG cells treated with methapyrilene. Importantly, the decrease of transferrin at mRNA and protein levels occurred after the treatment with a low dose of methapyrilene that exhibited minimal cytotoxicity. These results demonstrate the significance of the dysregulation of hepatic iron metabolism in the pathogenesis and mechanism of chemical-induced liver toxicity and suggest that these changes may be sensitive and useful indicators of potentially hepatotoxic chemicals. Published by Elsevier B.V.

Adaptation to HIF-1 deficiency by upregulation of the AMP/ATP ratio and phosphofructokinase activation in hepatomas.

PubMed

Golinska, Monika; Troy, Helen; Chung, Yuen-Li; McSheehy, Paul M; Mayr, Manuel; Yin, Xiaoke; Ly, Lucy; Williams, Kaye J; Airley, Rachel E; Harris, Adrian L; Latigo, John; Perumal, Meg; Aboagye, Eric O; Perrett, David; Stubbs, Marion; Griffiths, John R

2011-05-25

HIF-1 deficiency has marked effects on tumour glycolysis and growth. We therefore investigated the consequences of HIF-1 deficiency in mice, using the well established Hepa-1 wild-type (WT) and HIF-1β-deficient (c4) model. These mechanisms could be clinically relevant, since HIF-1 is now a therapeutic target. Hepa-1 WT and c4 tumours grown in vivo were analysed by 18FDG-PET and 19FDG Magnetic Resonance Spectroscopy for glucose uptake; by HPLC for adenine nucleotides; by immunohistochemistry for GLUTs; by immunoblotting and by DIGE followed by tandem mass spectrometry for protein expression; and by classical enzymatic methods for enzyme activity. HIF-1β deficient Hepa-1 c4 tumours grew significantly more slowly than WT tumours, and (as expected) showed significantly lower expression of many glycolytic enzymes. However, HIF-1β deficiency caused no significant change in the rate of glucose uptake in c4 tumours compared to WT when assessed in vivo by measuring fluoro-deoxyglucose (FDG) uptake. Immunohistochemistry demonstrated less GLUT-1 in c4 tumours, whereas GLUT-2 (liver type) was similar to WT. Factors that might upregulate glucose uptake independently of HIF-1 (phospho-Akt, c-Myc) were shown to have either lower or similar expression in c4 compared to WT tumours. However the AMP/ATP ratio was 4.5 fold higher (p < 0.01) in c4 tumours, and phosphofructokinase-1 (PFK-1) activity, measured at prevailing cellular ATP and AMP concentrations, was up to two-fold higher in homogenates of the deficient c4 cells and tumours compared to WT (p < 0.001), suggesting that allosteric PFK activation could explain their normal level of glycolysis. Phospho AMP-Kinase was also higher in the c4 tumours. Despite their defective HIF-1 and consequent down-regulation of glycolytic enzyme expression, Hepa-1 c4 tumours maintain glucose uptake and glycolysis because the resulting low [ATP] high [AMP] allosterically activate PFK-1. This mechanism of resistance would keep glycolysis functioning and also result in activation of AMP-Kinase and growth inhibition; it may have major implications for the therapeutic activity of HIF inhibitors in vivo. Interestingly, this control mechanism does not involve transcriptional control or proteomics, but rather the classical activation and inhibition mechanisms of glycolytic enzymes.

[Distribution diversity of integrins and calcium channels on major human and mouse host cells of Leptospira species].

PubMed

Li, Cheng-xue; Zhao, Xin; Qian, Jing; Yan, Jie

2012-07-01

To determine the distribution of integrins and calcium channels on major human and mouse host cells of Leptospira species. The expression of β1, β2 and β3 integrins was detected with immunofluorescence assay on the surface of human monocyte line THP-1, mouse mononuclear-macrophage-like cell line J774A.1, human vascular endothelial cell line HUVEC, mouse vascular endothelial cell EOMA, human hepatocyte line L-02, mouse hepatocyte line Hepa1-6, human renal tubular epithelial cell line HEK-293, mouse glomerular membrane epithelial cell line SV40-MES13, mouse collagen blast line NIH/3T3, human and mouse platelets. The distribution of voltage gate control calcium channels Cav3.1, Cav3.2, Cav3.3 and Cav2.3, and receptor gate calcium channels P(2)X(1), P(2)2X(2), P(2)X(3), P(2)X(4), P(2)X(5), P(2)X(6) and P(2)X(7) were determined with Western blot assay. β1 integrin proteins were positively expressed on the membrane surface of J774A.1, THP-1, HUVEC, EOMA, L-02, Hepa1-6 and HEK-239 cells as well as human and mouse platelets. β2 integrin proteins were expressed on the membrane surface of J774A.1, THP-1, HUVEC, EOMA, and NIH/3T3 cells. β3 integrin proteins were expressed on the membrane surface of J774A.1, THP-1, HUVEC, EOMA, Hepa1-6, HEK-239 and NIH/3T3 cells as well as human and mouse platelets. P(2)X(1) receptor gate calcium channel was expressed on the membrane surface of human and mouse platelets, while P(2)X(5) receptor gate calcium channel was expressed on the membrane surface of J774A.1, THP-1, L-02, Hepa1-6, HEK-239 and HUVEC cells. However, the other calcium channels were not detected on the tested cell lines or platelets. There is a large distribution diversity of integrins and calcium channel proteins on the major human and mouse host cells of Leptospira species, which may be associated with the differences of leptospira-induced injury in different host cells.

Potential antitumor activity of novel DODAC/PHO-S liposomes

PubMed Central

Luna, Arthur Cássio de Lima; Saraiva, Greice Kelle Viegas; Filho, Otaviano Mendonça Ribeiro; Chierice, Gilberto Orivaldo; Neto, Salvador Claro; Cuccovia, Iolanda Midea; Maria, Durvanei Augusto

2016-01-01

In recent studies, we showed that synthetic phosphoethanolamine (PHO-S) has a great potential for inducing cell death in several tumor cell lines without damage to normal cells. However, its cytotoxic effect and selectivity against tumor cells could increase with encapsulation in cationic liposomes, such as dioctadecyldimethylammonium chloride (DODAC), due to electrostatic interactions between these liposomes and tumor cell membranes. Our aim was to use cationic liposomes to deliver PHO-S and to furthermore maximize the therapeutic effect of this compound. DODAC liposomes containing PHO-S (DODAC/PHO-S), at concentrations of 0.3–2.0 mM, prepared by ultrasonication, were analyzed by scanning electron microscopy (SEM) and dynamic light scattering. The cytotoxic effect of DODAC/PHO-S on B16F10 cells, Hepa1c1c7 cells, and human umbilical vein endothelial cells (HUVECs) was assessed by MTT assay. Cell cycle phases of B16F10 cells were analyzed by flow cytometry and the morphological changes by SEM, after treatment. The liposomes were spherical and polydisperse in solution. The liposomes were stable, presenting an average of ∼50% of PHO-S encapsulation, with a small reduction after 40 days. DODAC demonstrated efficient PHO-S delivery, with the lowest values of IC50% (concentration that inhibits 50% of the growth of cells) for tumor cells, compared with PHO-S alone, with an IC50% value of 0.8 mM for B16F10 cells and 0.2 mM for Hepa1c1c7 cells, and without significant effects on endothelial cells. The Hepa1c1c7 cells showed greater sensitivity to the DODAC/PHO-S formulation when compared to B16F10 cells and HUVECs. The use of DODAC/PHO-S on B16F10 cells induced G2/M-phase cell cycle arrest, with the proportion significantly greater than that treated with PHO-S alone. The morphological analysis of B16F10 cells by SEM showed changes such as “bleb” formation, cell detachment, cytoplasmic retraction, and apoptotic bodies after DODAC/PHO-S treatment. Cationic liposomal formulation for PHO-S delivery promoted cytotoxicity more selectively and effectively against B16F10 and Hepa1c1c7 cells. Thus, the DODAC/PHO-S liposomal formulation presents great potential for preclinical studies. PMID:27143880

Effectiveness of dust control methods for crystalline silica and respirable suspended particulate matter exposure during manual concrete surface grinding.

PubMed

Akbar-Khanzadeh, Farhang; Milz, Sheryl A; Wagner, Cynthia D; Bisesi, Michael S; Ames, April L; Khuder, Sadik; Susi, Pam; Akbar-Khanzadeh, Mahboubeh

2010-12-01

Concrete grinding exposes workers to unacceptable levels of crystalline silica dust, known to cause diseases such as silicosis and possibly lung cancer. This study examined the influence of major factors of exposure and effectiveness of existing dust control methods by simulating field concrete grinding in an enclosed workplace laboratory. Air was monitored during 201 concrete grinding sessions while using a variety of grinders, accessories, and existing dust control methods, including general ventilation (GV), local exhaust ventilation (LEV), and wet grinding. Task-specific geometric mean (GM) of respirable crystalline silica dust concentrations (mg/m³ for LEV:HEPA-, LEV:Shop-vac-, wet-, and uncontrolled-grinding, while GV was off/on, were 0.17/0.09, 0.57/0.13, 1.11/0.44, and 23.1/6.80, respectively. Silica dust concentrations (mg/m³ using 100-125 mm (4-5 inch) and 180 mm (7 inch) grinding cups were 0.53/0.22 and 2.43/0.56, respectively. GM concentrations of silica dust were significantly lower for (1) GV on (66.0%) vs. off, and (2) LEV:HEPA- (99.0%), LEV:Shop-vac- (98.1%) or wet- (94.4%) vs. uncontrolled-grinding. Task-specific GM of respirable suspended particulate matter (RSP) concentrations (mg/m³ for LEV:HEPA-, LEV:Shop-vac-, wet-, and uncontrolled grinding, while GV was off/on, were 1.58/0.63, 7.20/1.15, 9.52/4.13, and 152/47.8, respectively. GM concentrations of RSP using 100-125 mm and 180 mm grinding cups were 4.78/1.62 and 22.2/5.06, respectively. GM concentrations of RSP were significantly lower for (1) GV on (70.2%) vs. off, and (2) LEV:HEPA- (98.9%), LEV:Shop-vac- (96.9%) or wet- (92.6%) vs. uncontrolled grinding. Silica dust and RSP were not significantly affected by (1) orientation of grinding surfaces (vertical vs. inclined); (2) water flow rates for wet grinding; (3) length of task-specific sampling time; or, (4) among cup sizes of 100, 115 or 125 mm. No combination of factors or control methods reduced an 8-hr exposure level to below the recommended criterion of 0.025 mg/m³ for crystalline silica, requiring further refinement in engineering controls, administrative controls, or the use of respirators.

Murine hepatic aldehyde dehydrogenase 1a1 is a major contributor to oxidation of aldehydes formed by lipid peroxidation

PubMed Central

Makia, Ngome L.; Bojang, Pasano; Falkner, K. Cameron; Conklin, Daniel J.; Prough, Russell A.

2015-01-01

Reactive lipid aldehydes are implicated in the pathogenesis of various oxidative stress-mediated diseases, including non-alcoholic steatohepatitis, atherosclerosis, Alzheimer’s and cataract. In the present study, we sought to define which hepatic Aldh isoform plays a major role in detoxification of lipid-derived aldehydes, such as acrolein and HNE by enzyme kinetic and gene expression studies. The catalytic efficiencies for metabolism of acrolein by Aldh1a1 was comparable to that of Aldh3a1 (Vmax/Km = 23). However, Aldh1a1 exhibits far higher affinity for acrolein (Km = 23.2 μM) compared to Aldh3a1 (Km = 464 μM). Aldh1a1 displays a 3-fold higher catalytic efficiency for HNE than Aldh3a1 (218 vs 69 ml/min/mg). The endogenous Aldh1a1 gene was highly expressed in mouse liver and a liver-derived cell line (Hepa-1c1c7) compared to Aldh2, Aldh1b1 and Aldh3a1. Aldh1a1 mRNA levels was 34-fold and 73-fold higher than Aldh2 in mouse liver and Hepa-1c1c7 cells respectively. Aldh3a1 gene was absent in mouse liver, but moderately expressed in Hepa-1c1c7 cells compared to Aldh1a1. We demonstrated that knockdown of Aldh1a1 expression by siRNA caused Hepa-1c1c7 cells to be more sensitive to acrolein-induced cell death and resulted in increased accumulation of acrolein-protein adducts and caspase 3 activation. These results indicate that Aldh1a1 plays a major role in cellular defense against oxidative damage induced by reactive lipid aldehydes in mouse liver. We also noted that hepatic Aldh1a1 mRNA levels were significantly increased (≈ 3 fold) in acrolein-fed mice compared to control. In addition, hepatic cytosolic ALDH activity was induced by acrolein when 1 mM NAD+ was used as cofactor, suggesting an Aldh1a1-protective mechanism against acrolein toxicity in mice liver. Thus, mechanisms to induce Aldh1a1 gene expression may provide a useful rationale for therapeutic protection against oxidative stress-induced pathologies. PMID:21256123

High exhaust temperature, zoned, electrically-heated particulate matter filter

DOEpatents

Gonze, Eugene V.; Paratore, Jr., Michael J.; Bhatia, Garima

2015-09-22

A system includes a particulate matter (PM) filter, an electric heater, and a control circuit. The electric heater includes multiple zones, which each correspond to longitudinal zones along a length of the PM filter. A first zone includes multiple discontinuous sub-zones. The control circuit determines whether regeneration is needed based on an estimated level of loading of the PM filter and an exhaust flow rate. In response to a determination that regeneration is needed, the control circuit: controls an operating parameter of an engine to increase an exhaust temperature to a first temperature during a first period; after the first period, activates the first zone; deactivates the first zone in response to a minimum filter face temperature being reached; subsequent to deactivating the first zone, activates a second zone; and deactivates the second zone in response to the minimum filter face temperature being reached.

Optimization of OT-MACH Filter Generation for Target Recognition

NASA Technical Reports Server (NTRS)

Johnson, Oliver C.; Edens, Weston; Lu, Thomas T.; Chao, Tien-Hsin

2009-01-01

An automatic Optimum Trade-off Maximum Average Correlation Height (OT-MACH) filter generator for use in a gray-scale optical correlator (GOC) has been developed for improved target detection at JPL. While the OT-MACH filter has been shown to be an optimal filter for target detection, actually solving for the optimum is too computationally intensive for multiple targets. Instead, an adaptive step gradient descent method was tested to iteratively optimize the three OT-MACH parameters, alpha, beta, and gamma. The feedback for the gradient descent method was a composite of the performance measures, correlation peak height and peak to side lobe ratio. The automated method generated and tested multiple filters in order to approach the optimal filter quicker and more reliably than the current manual method. Initial usage and testing has shown preliminary success at finding an approximation of the optimal filter, in terms of alpha, beta, gamma values. This corresponded to a substantial improvement in detection performance where the true positive rate increased for the same average false positives per image.

Fabrication and characterization of multi-stopband Fabry-Pérot filter array for nanospectrometers in the VIS range using SCIL nanoimprint technology

NASA Astrophysics Data System (ADS)

Shen, Yannan; Istock, André; Zaman, Anik; Woidt, Carsten; Hillmer, Hartmut

2018-05-01

Miniaturization of optical spectrometers can be achieved by Fabry-Pérot (FP) filter arrays. Each FP filter consists of two parallel highly reflecting mirrors and a resonance cavity in between. Originating from different individual cavity heights, each filter transmits a narrow spectral band (transmission line) with different wavelengths. Considering the fabrication efficiency, plasma enhanced chemical vapor deposition (PECVD) technology is applied to implement the high-optical-quality distributed Bragg reflectors (DBRs), while substrate conformal imprint lithography (one type of nanoimprint technology) is utilized to achieve the multiple cavities in just a single step. The FP filter array fabricated by nanoimprint combined with corresponding detector array builds a so-called "nanospectrometer". However, the silicon nitride and silicon dioxide stacks deposited by PECVD result in a limited stopband width of DBR (i.e., < 100 nm), which then limits the sensing range of filter arrays. However, an extension of the spectral range of filter arrays is desired and the topic of this investigation. In this work, multiple DBRs with different central wavelengths (λ c) are structured, deposited, and combined on a single substrate to enlarge the entire stopband. Cavity arrays are successfully aligned and imprinted over such terrace like surface in a single step. With this method, small chip size of filter arrays can be preserved, and the fabrication procedure of multiple resonance cavities is kept efficient as well. The detecting range of filter arrays is increased from roughly 50 nm with single DBR to 163 nm with three different DBRs.

Successful Training of Filtering Mechanisms in Multiple Object Tracking Does Not Transfer to Filtering Mechanisms in a Visual Working Memory Task: Behavioral and Electrophysiological Evidence

ERIC Educational Resources Information Center

Arend, Anna M.; Zimmer, Hubert D.

2012-01-01

In this training study, we aimed to selectively train participants' filtering mechanisms to enhance visual working memory (WM) efficiency. The highly restricted nature of visual WM capacity renders efficient filtering mechanisms crucial for its successful functioning. Filtering efficiency in visual WM can be measured via the lateralized change…

Real-time optical multiple object recognition and tracking system and method

NASA Technical Reports Server (NTRS)

Chao, Tien-Hsin (Inventor); Liu, Hua Kuang (Inventor)

1987-01-01

The invention relates to an apparatus and associated methods for the optical recognition and tracking of multiple objects in real time. Multiple point spatial filters are employed that pre-define the objects to be recognized at run-time. The system takes the basic technology of a Vander Lugt filter and adds a hololens. The technique replaces time, space and cost-intensive digital techniques. In place of multiple objects, the system can also recognize multiple orientations of a single object. This later capability has potential for space applications where space and weight are at a premium.

Triple-Quantum Filtered NMR Imaging of Sodium -23 in the Human Brain

NASA Astrophysics Data System (ADS)

Keltner, John Robinson

In the past multiple-quantum filtered imaging of biexponential relaxation sodium-23 nuclei in the human brain has been limited by low signal to noise ratios; this thesis demonstrates that such imaging is feasible when using a modified gradient-selected triple-quantum filter at a repetition time which maximizes the signal to noise ratio. Nuclear magnetic resonance imaging of biexponential relaxation sodium-23 (^{23}Na) nuclei in the human brain may be useful for detecting ischemia, cancer, and pathophysiology related to manic-depression. Multiple -quantum filters may be used to selectively image biexponential relaxation ^{23}Na signals since these filters suppress single-exponential relaxation ^{23}Na signals. In this thesis, the typical repetition times (200 -300 ms) used for in vivo multiple-quantum filtered ^{23}Na experiments are shown to be approximately 5 times greater than the optimal repetition time which maximizes multiple-quantum filtered SNR. Calculations and experimental verification show that the gradient-selected triple-quantum (GS3Q) filtered SNR for ^ {23}Na in a 4% agarose gel increases by a factor of two as the repetition time decreases from 300 ms to 55 ms. It is observed that a simple reduction of repetition time also increases spurious single-quantum signals from GS3Q filtered experiments. Irreducible superoperator calculations have been used to design a modified GS3Q filter which more effectively suppresses the spurious single-quantum signals. The modified GS3Q filter includes a preparatory crusher gradient and two-step-phase cycling. Using the modified GS3Q filter and a repetition time of 70 ms, a three dimensional triple-quantum filtered image of a phantom modelling ^{23} Na in the brain was obtained. The phantom consisted of two 4 cm diameter spheres inside of a 8.5 cm x 7 cm ellipsoid. The two spheres contained 0.012 and 0.024 M ^{23}Na in 4% agarose gel. Surrounding the spheres and inside the ellipsoid was 0.03 M aqueous ^{23}Na. The image dimensions were 16 x 16 x 16 voxels with the dimension of a voxel being 1.5 x 1.5 x 1.5 cm^3. The signal to noise ratio for the GS3Q filtered ^ {23}Na signal from the 0.012 and 0.024 M ^{23}Na spheres was 17 and 30 for a 54 minute experiment at 2.35 T. (Abstract shortened by UMI.).

National policy on physical activity: the development of a policy audit tool.

PubMed

Bull, Fiona C; Milton, Karen; Kahlmeier, Sonja

2014-02-01

Physical inactivity is a leading risk factor for noncommunicable disease worldwide. Increasing physical activity requires large scale actions and relevant, supportive national policy across multiple sectors. The policy audit tool (PAT) was developed to provide a standardized instrument to assess national policy approaches to physical activity. A draft tool, based on earlier work, was developed and pilot-tested in 7 countries. After several rounds of revisions, the final PAT comprises 27 items and collects information on 1) government structure, 2) development and content of identified key policies across multiple sectors, 3) the experience of policy implementation at both the national and local level, and 4) a summary of the PAT completion process. PAT provides a standardized instrument for assessing progress of national policy on physical activity. Engaging a diverse international group of countries in the development helped ensure PAT has applicability across a wide range of countries and contexts. Experiences from the development of the PAT suggests that undertaking an audit of health enhancing physical activity (HEPA) policy can stimulate greater awareness of current policy opportunities and gaps, promote critical debate across sectors, and provide a catalyst for collaboration on policy level actions. The final tool is available online.

Using focused plenoptic cameras for rich image capture.

PubMed

Georgiev, T; Lumsdaine, A; Chunev, G

2011-01-01

This approach uses a focused plenoptic camera to capture the plenoptic function's rich "non 3D" structure. It employs two techniques. The first simultaneously captures multiple exposures (or other aspects) based on a microlens array having an interleaved set of different filters. The second places multiple filters at the main lens aperture.

Passive fetal heart rate monitoring apparatus and method with enhanced fetal heart beat discrimination

NASA Technical Reports Server (NTRS)

Zahorian, Stephen A. (Inventor); Livingston, David L. (Inventor); Pretlow, III, Robert A. (Inventor)

1996-01-01

An apparatus for acquiring signals emitted by a fetus, identifying fetal heart beats and determining a fetal heart rate. Multiple sensor signals are outputted by a passive fetal heart rate monitoring sensor. Multiple parallel nonlinear filters filter these multiple sensor signals to identify fetal heart beats in the signal data. A processor determines a fetal heart rate based on these identified fetal heart beats. The processor includes the use of a figure of merit weighting of heart rate estimates based on the identified heart beats from each filter for each signal. The fetal heart rate thus determined is outputted to a display, storage, or communications channel. A method for enhanced fetal heart beat discrimination includes acquiring signals from a fetus, identifying fetal heart beats from the signals by multiple parallel nonlinear filtering, and determining a fetal heart rate based on the identified fetal heart beats. A figure of merit operation in this method provides for weighting a plurality of fetal heart rate estimates based on the identified fetal heart beats and selecting the highest ranking fetal heart rate estimate.

Passive fetal heart rate monitoring apparatus and method with enhanced fetal heart beat discrimination

NASA Technical Reports Server (NTRS)

Zahorian, Stephen A. (Inventor); Livingston, David L. (Inventor); Pretlow, Robert A., III (Inventor)

1994-01-01

An apparatus for acquiring signals emitted by a fetus, identifying fetal heart beats and determining a fetal heart rate is presented. Multiple sensor signals are outputted by a passive fetal heart rate monitoring sensor. Multiple parallel nonlinear filters filter these multiple sensor signals to identify fetal heart beats in the signal data. A processor determines a fetal heart rate based on these identified fetal heart beats. The processor includes the use of a figure of merit weighting of heart rate estimates based on the identified heart beats from each filter for each signal. The fetal heart rate thus determined is outputted to a display, storage, or communications channel. A method for enhanced fetal heart beat discrimination includes acquiring signals from a fetus, identifying fetal heart beats from the signals by multiple parallel nonlinear filtering, and determining a fetal heart rate based on the identified fetal heart beats. A figure of merit operation in this method provides for weighting a plurality of fetal heart rate estimates based on the identified fetal heart beats and selecting the highest ranking fetal heart rate estimate.

Universal filtered multi-carrier system for asynchronous uplink transmission in optical access network

NASA Astrophysics Data System (ADS)

Kang, Soo-Min; Kim, Chang-Hun; Han, Sang-Kook

2016-02-01

In passive optical network (PON), orthogonal frequency division multiplexing (OFDM) has been studied actively due to its advantages such as high spectra efficiency (SE), dynamic resource allocation in time or frequency domain, and dispersion robustness. However, orthogonal frequency division multiple access (OFDMA)-PON requires tight synchronization among multiple access signals. If not, frequency orthogonality could not be maintained. Also its sidelobe causes inter-channel interference (ICI) to adjacent channel. To prevent ICI caused by high sidelobes, guard band (GB) is usually used which degrades SE. Thus, OFDMA-PON is not suitable for asynchronous uplink transmission in optical access network. In this paper, we propose intensity modulation/direct detection (IM/DD) based universal filtered multi-carrier (UFMC) PON for asynchronous multiple access. The UFMC uses subband filtering to subsets of subcarriers. Since it reduces sidelobe of each subband by applying subband filtering, it could achieve better performance compared to OFDM. For the experimental demonstration, different sample delay was applied to subbands to implement asynchronous transmission condition. As a result, time synchronization robustness of UFMC was verified in asynchronous multiple access system.

Multiple microRNAs function as self-protective modules in acetaminophen-induced hepatotoxicity in humans.

PubMed

Yu, Dianke; Wu, Leihong; Gill, Pritmohinder; Tolleson, William H; Chen, Si; Sun, Jinchun; Knox, Bridgett; Jin, Yaqiong; Xiao, Wenming; Hong, Huixiao; Wang, Yong; Ren, Zhen; Guo, Lei; Mei, Nan; Guo, Yongli; Yang, Xi; Shi, Leming; Chen, Yinting; Zeng, Linjuan; Dreval, Kostiantyn; Tryndyak, Volodymyr; Pogribny, Igor; Fang, Hong; Shi, Tieliu; McCullough, Sandra; Bhattacharyya, Sudeepa; Schnackenberg, Laura; Mattes, William; Beger, Richard D; James, Laura; Tong, Weida; Ning, Baitang

2018-02-01

Acetaminophen (APAP) overdose is the leading cause of acute liver failure. Yet the mechanisms underlying adaptive tolerance toward APAP-induced liver injury are not fully understood. To better understand molecular mechanisms contributing to adaptive tolerance to APAP is an underpinning foundation for APAP-related precision medicine. In the current study, the mRNA and microRNA (miRNA) expression profiles derived from next generation sequencing data for APAP-treated (5 and 10 mM) HepaRG cells and controls were analyzed systematically. Putative miRNAs targeting key dysregulated genes involved in APAP hepatotoxicity were selected using in silico prediction algorithms, un-biased gene ontology, and network analyses. Luciferase reporter assays, RNA electrophoresis mobility shift assays, and miRNA pull-down assays were performed to investigate the role of miRNAs affecting the expression of dysregulated genes. Levels of selected miRNAs were measured in serum samples obtained from children with APAP overdose (58.6-559.4 mg/kg) and from healthy controls. As results, 2758 differentially expressed genes and 47 miRNAs were identified. Four of these miRNAs (hsa-miR-224-5p, hsa-miR-320a, hsa-miR-449a, and hsa-miR-877-5p) suppressed drug metabolizing enzyme (DME) levels involved in APAP-induced liver injury by downregulating HNF1A, HNF4A and NR1I2 expression. Exogenous transfection of these miRNAs into HepaRG cells effectively rescued them from APAP toxicity, as indicated by decreased alanine aminotransferase levels. Importantly, hsa-miR-320a and hsa-miR-877-5p levels were significantly elevated in serum samples obtained from children with APAP overdose compared to health controls. Collectively, these data indicate that hsa-miR-224-5p, hsa-miR-320a, hsa-miR-449a, and hsa-miR-877-5p suppress DME expression involved in APAP-induced hepatotoxicity and they contribute to an adaptive response in hepatocytes.

Two-Microphone Spatial Filtering Improves Speech Reception for Cochlear-Implant Users in Reverberant Conditions With Multiple Noise Sources

PubMed Central

2014-01-01

This study evaluates a spatial-filtering algorithm as a method to improve speech reception for cochlear-implant (CI) users in reverberant environments with multiple noise sources. The algorithm was designed to filter sounds using phase differences between two microphones situated 1 cm apart in a behind-the-ear hearing-aid capsule. Speech reception thresholds (SRTs) were measured using a Coordinate Response Measure for six CI users in 27 listening conditions including each combination of reverberation level (T60 = 0, 270, and 540 ms), number of noise sources (1, 4, and 11), and signal-processing algorithm (omnidirectional response, dipole-directional response, and spatial-filtering algorithm). Noise sources were time-reversed speech segments randomly drawn from the Institute of Electrical and Electronics Engineers sentence recordings. Target speech and noise sources were processed using a room simulation method allowing precise control over reverberation times and sound-source locations. The spatial-filtering algorithm was found to provide improvements in SRTs on the order of 6.5 to 11.0 dB across listening conditions compared with the omnidirectional response. This result indicates that such phase-based spatial filtering can improve speech reception for CI users even in highly reverberant conditions with multiple noise sources. PMID:25330772

A multi-reference filtered-x-Newton narrowband algorithm for active isolation of vibration and experimental investigations

NASA Astrophysics Data System (ADS)

Wang, Chun-yu; He, Lin; Li, Yan; Shuai, Chang-geng

2018-01-01

In engineering applications, ship machinery vibration may be induced by multiple rotational machines sharing a common vibration isolation platform and operating at the same time, and multiple sinusoidal components may be excited. These components may be located at frequencies with large differences or at very close frequencies. A multi-reference filtered-x Newton narrowband (MRFx-Newton) algorithm is proposed to control these multiple sinusoidal components in an MIMO (multiple input and multiple output) system, especially for those located at very close frequencies. The proposed MRFx-Newton algorithm can decouple and suppress multiple sinusoidal components located in the same narrow frequency band even though such components cannot be separated from each other by a narrowband-pass filter. Like the Fx-Newton algorithm, good real-time performance is also achieved by the faster convergence speed brought by the 2nd-order inverse secondary-path filter in the time domain. Experiments are also conducted to verify the feasibility and test the performance of the proposed algorithm installed in an active-passive vibration isolation system in suppressing the vibration excited by an artificial source and air compressor/s. The results show that the proposed algorithm not only has comparable convergence rate as the Fx-Newton algorithm but also has better real-time performance and robustness than the Fx-Newton algorithm in active control of the vibration induced by multiple sound sources/rotational machines working on a shared platform.

A new fault diagnosis algorithm for AUV cooperative localization system

NASA Astrophysics Data System (ADS)

Shi, Hongyang; Miao, Zhiyong; Zhang, Yi

2017-10-01

Multiple AUVs cooperative localization as a new kind of underwater positioning technology, not only can improve the positioning accuracy, but also has many advantages the single AUV does not have. It is necessary to detect and isolate the fault to increase the reliability and availability of the AUVs cooperative localization system. In this paper, the Extended Multiple Model Adaptive Cubature Kalmam Filter (EMMACKF) method is presented to detect the fault. The sensor failures are simulated based on the off-line experimental data. Experimental results have shown that the faulty apparatus can be diagnosed effectively using the proposed method. Compared with Multiple Model Adaptive Extended Kalman Filter and Multi-Model Adaptive Unscented Kalman Filter, both accuracy and timelines have been improved to some extent.

Invasive fungal infection following chemotherapy for acute myeloid leukaemia-Experience from a developing country.

PubMed

Korula, Anu; Abraham, Aby; Abubacker, Fouzia N; Viswabandya, Auro; Lakshmi, Kavitha M; Abraham, O C; Rupali, Priscilla; Varghese, George M; Michael, Joy S; Srivastava, Alok; Mathews, Vikram; George, Biju

2017-10-01

The incidence of invasive fungal infections (IFI) is believed to be higher in patients with acute myeloid leukaemia (AML) undergoing chemotherapy in non-HEPA-filtered rooms. The aim of this study is to review the incidence of IFI in a large cohort of patients with AML treated at a single centre in India. Two hundred and twenty-two patients with AML treated with either induction chemotherapy or salvage chemotherapy between 2008 and 2013 were studied retrospectively. IFI was defined as per the revised EORTC-MSG criteria. Data on type of chemotherapy, prophylactic strategies, engraftment (ANC>500), the presence of IFI and survival were collected. IFI was diagnosed in 86 patients (38.7%) with proven IFI in 12 (5.4%). Use of posaconazole prophylaxis (P=.001) was the only factor associated with reduced incidence of IFI. Survival in patients with proven IFI was lower than those without proven IFI, but not statistically significant (59.4% vs 78.5%; P=.139). There is a high incidence of IFI during induction chemotherapy for acute myeloid leukaemia in developing countries. Posaconazole prophylaxis was associated with a significantly lower incidence of IFI. Optimal yet cost-effective strategies for prevention and early diagnosis of IFI are required to improve survival in patients undergoing chemotherapy for AML. © 2017 Blackwell Verlag GmbH.

Airborne Dust in Space Vehicles and Habitats

NASA Technical Reports Server (NTRS)

James, John

2006-01-01

Airborne dust, suspended inside a space vehicle or in future celestial habitats, can present a serious threat to crew health if it is not controlled. During the Apollo missions to the moon, lunar dust brought inside the capsule caused eye irritation and breathing difficulty to the crew when they launched from the moon and re-acquired "microgravity." During Shuttle flights reactive and toxic dusts such as lithium hydroxide have created a risk to crew health, and fine particles from combustion events can be especially worrisome. Under nominal spaceflight conditions, airborne dusts and particles tend to be larger than on earth because of the absence of gravity settling. Aboard the ISS, dusts are effectively managed by HEPA filters, although floating dust in newly-arrived modules can be a nuisance. Future missions to the moon and to Mars will present additional challenges because of the possibility that external dust will enter the breathing atmosphere of the habitat and reach the crew's respiratory system. Testing with simulated lunar and Martian dust has shown that these materials are toxic when placed into the lungs of test animals. Defining and evaluating the physical and chemical properties of Martian dusts through robotic missions will challenge our ability to prepare better dust simulants and to determine the risk to crew health from exposure to such dusts.

Performance analysis of air conditioning system and airflow simulation in an operating theater

NASA Astrophysics Data System (ADS)

Alhamid, Muhammad Idrus; Budihardjo, Rahmat

2018-02-01

The importance of maintaining performance of a hospital operating theater is to establish an adequate circulation of clean air within the room. The parameter of air distribution in a space should be based on Air Changes per Hour (ACH) to maintain a positive room pressure. The dispersion of airborne particles in the operating theater was governed by regulating the air distribution so that the operating theater meets clean room standards ie ISO 14664 and ASHRAE 170. Here, we introduced several input parameters in a simulation environment to observe the pressure distribution in the room. Input parameters were air temperature, air velocity and volumetric flow rate entering and leaving room for existing and designed condition. In the existing operating theatre, several observations were found. It was found that the outlet air velocity at the HEPA filter above the operating table was too high thus causing a turbulent airflow pattern. Moreover, the setting temperature at 19°C was found to be too low. The supply of air into the room was observed at lower than 20 ACH which is under the standard requirement. Our simulation using FloVent 8.2™ program showed that not only airflow turbulence could be reduced but also the amount of particle contamination could also be minimized.

Safety Precautions and Operating Procedures in an (A)BSL-4 Laboratory: 3. Aerobiology.

PubMed

Bohannon, J Kyle; Janosko, Krisztina; Holbrook, Michael R; Barr, Jason; Pusl, Daniela; Bollinger, Laura; Coe, Linda; Hensley, Lisa E; Jahrling, Peter B; Wada, Jiro; Kuhn, Jens H; Lackemeyer, Matthew G

2016-10-03

Aerosol or inhalational studies of high-consequence pathogens have recently been increasing in number due to the perceived threat of intentional aerosol releases or unexpected natural aerosol transmission. Specific laboratories designed to perform these experiments require tremendous engineering controls to provide a safe and secure working environment and constant systems maintenance to sustain functionality. Class III biosafety cabinets, also referred to as gloveboxes, are gas-tight enclosures with non-opening windows. These cabinets are maintained under negative pressure by double high-efficiency-particulate-air (HEPA)-filtered exhaust systems and are the ideal primary containment for housing aerosolization equipment. A well planned workflow between staff members within high containment from, for instance, an animal biosafety level-4 (ABSL-4) suit laboratory to the ABSL-4 cabinet laboratory is a crucial component for successful experimentation. For smooth study execution, establishing a communication network, moving equipment and subjects, and setting up and placing equipment, requires staff members to meticulously plan procedures prior to study initiation. Here, we provide an overview and a visual representation of how aerobiology research is conducted at the National Institutes of Health, National Institute of Allergy and Infectious Diseases Integrated Research Facility at Fort Detrick, Maryland, USA, within an ABSL-4 environment.

Assessment of Nanoparticle Exposure in Nanosilica Handling Process: Including Characteristics of Nanoparticles Leaking from a Vacuum Cleaner

PubMed Central

KIM, Boowook; KIM, Hyunwook; YU, Il Je

2013-01-01

Nanosilica is one of the most widely used nanomaterials across the world. However, their assessment data on the occupational exposure to nanoparticles is insufficient. The present study performed an exposure monitoring in workplace environments where synthetic powders are prepared using fumed nanosilica. Furthermore, after it was observed during exposure monitoring that nanoparticles were emitted through leakage in a vacuum cleaner (even with a HEPA-filter installed in it), the properties of the leaked nanoparticles were also investigated. Workers were exposed to high-concentration nanosilica emitted into the air while pouring it into a container or transferring the container. The use of a vacuum cleaner with a leak (caused by an inadequate sealing) was found to be the origin of nanosilica dispersion in the indoor air. While the particle size of the nanosilica that emitted into the air (during the handling of nanosilica by a worker) was mostly over 100 nm or several microns (µm) due to the coagulation of particles, the size of nanosilica that leaked out of vacuum cleaner was almost similar to the primary size (mode diameter 11.5 nm). Analysis of area samples resulted in 20% (60% in terms of peak concentration) less than the analysis of the personals sample. PMID:24366536

Assessment of nanoparticle exposure in nanosilica handling process: including characteristics of nanoparticles leaking from a vacuum cleaner.

PubMed

Kim, Boowook; Kim, Hyunwook; Yu, Il Je

2014-01-01

Nanosilica is one of the most widely used nanomaterials across the world. However, their assessment data on the occupational exposure to nanoparticles is insufficient. The present study performed an exposure monitoring in workplace environments where synthetic powders are prepared using fumed nanosilica. Furthermore, after it was observed during exposure monitoring that nanoparticles were emitted through leakage in a vacuum cleaner (even with a HEPA-filter installed in it), the properties of the leaked nanoparticles were also investigated. Workers were exposed to high-concentration nanosilica emitted into the air while pouring it into a container or transferring the container. The use of a vacuum cleaner with a leak (caused by an inadequate sealing) was found to be the origin of nanosilica dispersion in the indoor air. While the particle size of the nanosilica that emitted into the air (during the handling of nanosilica by a worker) was mostly over 100 nm or several microns (µm) due to the coagulation of particles, the size of nanosilica that leaked out of vacuum cleaner was almost similar to the primary size (mode diameter 11.5 nm). Analysis of area samples resulted in 20% (60% in terms of peak concentration) less than the analysis of the personals sample.

Gold cleaning methods for preparation of cell culture surfaces for self-assembled monolayers of zwitterionic oligopeptides.

PubMed

Enomoto, Junko; Kageyama, Tatsuto; Myasnikova, Dina; Onishi, Kisaki; Kobayashi, Yuka; Taruno, Yoko; Kanai, Takahiro; Fukuda, Junji

2018-05-01

Self-assembled monolayers (SAMs) have been used to elucidate interactions between cells and material surface chemistry. Gold surfaces modified with oligopeptide SAMs exhibit several unique characteristics, such as cell-repulsive surfaces, micropatterns of cell adhesion and non-adhesion regions for control over cell microenvironments, and dynamic release of cells upon external stimuli under culture conditions. However, basic procedures for the preparation of oligopeptide SAMs, including appropriate cleaning methods of the gold surface before modification, have not been fully established. Because gold surfaces are readily contaminated with organic compounds in the air, cleaning methods may be critical for SAM formation. In this study, we examined the effects of four gold cleaning methods: dilute aqua regia, an ozone water, atmospheric plasma, and UV irradiation. Among the methods, UV irradiation most significantly improved the formation of oligopeptide SAMs in terms of repulsion of cells on the surfaces. We fabricated an apparatus with a UV light source, a rotation table, and HEPA filter, to treat a number of gold substrates simultaneously. Furthermore, UV-cleaned gold substrates were capable of detaching cell sheets without serious cell injury. This may potentially provide a stable and robust approach to oligopeptide SAM-based experiments for biomedical studies. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Industrial-hygiene survey report, Wabash Magnetic Company, Huntington, Indiana, May 24-26, 1988. [4,4'-methylenedianiline

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

Boeniger, M.F.

1989-01-01

A walk-through survey was made at Wabash Magnetic Company, located in Huntington, Indiana for the purpose of determining the extent of worker exposure to 4,4'-methylenedianiline (MDA) in a batch type mixing operation and user of B-stage resins. At this site the chemical was used as a hardening agent to produce the resins used to make transfer-molded parts. Air, wipe, bulk, and urine samples were taken to determine exposure levels. In both the formulating and molding departments, evidence was found for the possible inhalation of and dermal contact with MDA. Air concentrations were detectable, but were below the permissible exposure levelmore » of 10 parts per billion (ppb) proposed by OSHA. Of seven workers monitored by urinalysis, two were excreting detectable amounts of MDA with the higher concentration being 16 ppb. The author recommends a combination of modified work practices and alternative personal protection to reduce exposures. A vacuum installed with a HEPA filter should be used in the dry cleanup processes in the mixing and formulating departments and workers should wear a glove more resistant to permeation than the cotton ones now in use at the site. Gloves made of polyvinylchloride or natural latex are suggested.« less

Making healthy eating and physical activity policy practice: the design and overview of a group randomized controlled trial in afterschool programs.

PubMed

Beets, Michael W; Glenn Weaver, R; Turner-McGrievy, Gabrielle; Huberty, Jennifer; Ward, Dianne S; Freedman, Darcy A; Saunders, Ruth; Pate, Russell R; Beighle, Aaron; Hutto, Brent; Moore, Justin B

2014-07-01

National and state organizations have developed policies calling upon afterschool programs (ASPs, 3-6 pm) to serve a fruit or vegetable (FV) each day for snack, while eliminating foods and beverages high in added-sugars, and to ensure children accumulate a minimum of 30 min/d of moderate-to-vigorous physical activity (MVPA). Few efficacious and cost-effective strategies exist to assist ASP providers in achieving these important public health goals. This paper reports on the design and conceptual framework of Making Healthy Eating and Physical Activity (HEPA) Policy Practice in ASPs, a 3-year group randomized controlled trial testing the effectiveness of strategies designed to improve snacks served and increase MVPA in children attending community-based ASPs. Twenty ASPs, serving over 1800 children (6-12 years) will be enrolled and match-paired based on enrollment size, average daily min/d MVPA, and days/week FV served, with ASPs randomized after baseline data collection to immediate intervention or a 1-year delayed group. The framework employed, STEPs (Strategies To Enhance Practice), focuses on intentional programming of HEPA in each ASPs' daily schedule, and includes a grocery store partnership to reduce price barriers to purchasing FV, professional development training to promote physical activity to develop core physical activity competencies, as well as ongoing technical support/assistance. Primary outcome measures include children's accelerometry-derived MVPA and time spend sedentary while attending an ASP, direct observation of staff HEPA promoting and inhibiting behaviors, types of snacks served, and child consumption of snacks, as well as, cost of snacks via receipts and detailed accounting of intervention delivery costs to estimate cost-effectiveness. Copyright © 2014 Elsevier Inc. All rights reserved.

Genome-wide analysis of human constitutive androstane receptor (CAR) transcriptome in wild-type and CAR-knockout HepaRG cells.

PubMed

Li, Daochuan; Mackowiak, Bryan; Brayman, Timothy G; Mitchell, Michael; Zhang, Lei; Huang, Shiew-Mei; Wang, Hongbing

2015-11-01

The constitutive androstane receptor (CAR) modulates the transcription of numerous genes involving drug metabolism, energy homeostasis, and cell proliferation. Most functions of CAR however were defined from animal studies. Given the known species difference of CAR and the significant cross-talk between CAR and the pregnane X receptor (PXR), it is extremely difficult to decipher the exact role of human CAR (hCAR) in gene regulation, relying predominantly on pharmacological manipulations. Here, utilizing a newly generated hCAR-knockout (KO) HepaRG cell line, we carried out RNA-seq analysis of the global transcriptomes in wild-type (WT) and hCAR-KO HepaRG cells treated with CITCO, a selective hCAR agonist, phenobarbital (PB), a dual activator of hCAR and hPXR, or vehicle control. Real-time PCR assays in separate experiments were used to validate RNA-seq findings. Our results indicate that genes encoding drug-metabolizing enzymes are among the main clusters altered by both CITCO and PB. Specifically, CITCO significantly changed the expression of 135 genes in an hCAR-dependent manner, while PB altered the expression of 227 genes in WT cells of which 94 were simultaneously modulated in both cell lines reflecting dual effects of PB on hCAR/PXR. Notably, we found that many genes promoting cell proliferation and tumorigenesis were up-regulated in hCAR-KO cells, suggesting that hCAR may play an important role in cell growth that differs from mouse CAR. Together, our results reveal both novel and known targets of hCAR and support the role of hCAR in maintaining the homeostasis of metabolism and cell proliferation in the liver. Copyright © 2015 Elsevier Inc. All rights reserved.

A novel genotoxin-specific qPCR array based on the metabolically competent human HepaRG™ cell line as a rapid and reliable tool for improved in vitro hazard assessment.

PubMed

Ates, Gamze; Mertens, Birgit; Heymans, Anja; Verschaeve, Luc; Milushev, Dimiter; Vanparys, Philippe; Roosens, Nancy H C; De Keersmaecker, Sigrid C J; Rogiers, Vera; Doktorova, Tatyana Y

2018-04-01

Although the value of the regulatory accepted batteries for in vitro genotoxicity testing is recognized, they result in a high number of false positives. This has a major impact on society and industries developing novel compounds for pharmaceutical, chemical, and consumer products, as afflicted compounds have to be (prematurely) abandoned or further tested on animals. Using the metabolically competent human HepaRG ™ cell line and toxicogenomics approaches, we have developed an upgraded, innovative, and proprietary gene classifier. This gene classifier is based on transcriptomic changes induced by 12 genotoxic and 12 non-genotoxic reference compounds tested at sub-cytotoxic concentrations, i.e., IC10 concentrations as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The resulting gene classifier was translated into an easy-to-handle qPCR array that, as shown by pathway analysis, covers several different cellular processes related to genotoxicity. To further assess the predictivity of the tool, a set of 5 known positive and 5 known negative test compounds for genotoxicity was evaluated. In addition, 2 compounds with debatable genotoxicity data were tested to explore how the qPCR array would classify these. With an accuracy of 100%, when equivocal results were considered positive, the results showed that combining HepaRG ™ cells with a genotoxin-specific qPCR array can improve (geno)toxicological hazard assessment. In addition, the developed qPCR array was able to provide additional information on compounds for which so far debatable genotoxicity data are available. The results indicate that the new in vitro tool can improve human safety assessment of chemicals in general by basing predictions on mechanistic toxicogenomics information.

Making Healthy Eating and Physical Activity Policy Practice: The Design and Overview of a Group Randomized Controlled Trial in Afterschool Programs

PubMed Central

Beets, Michael W.; Weaver, R. Glenn; Turner-McGrievy, Gabrielle; Huberty, Jennifer; Ward, Dianne S.; Freedman, Darcy A.; Saunders, Ruth; Pate, Russell R.; Beighle, Aaron; Moore, Justin B.

2014-01-01

National and state organizations have developed policies calling upon afterschool programs (ASPs, 3-6pm) to serve a fruit or vegetable (FV) each day for snack, while eliminating foods and beverages high in added-sugars, and to ensure children accumulate a minimum of 30 min/d of moderate-to-vigorous physical activity (MVPA). Few efficacious and cost-effective strategies exist to assist ASP providers in achieving these important public health goals. This paper reports on the design and conceptual framework of Making Healthy Eating and Physical Activity (HEPA) Policy Practice in ASPs, a 3-year group randomized controlled trial testing the effectiveness of strategies designed to improve snacks served and increase MVPA in children attending community-based ASPs. Twenty ASPs, serving over 1,800 children (6-12yrs) will be enrolled and match-paired based on enrollment size, average daily min/d MVPA, and days/week FV served, with ASPs randomized after baseline data collection to immediate intervention or a 1-year delayed group. The framework employed, STEPs (Strategies To Enhance Practice), focuses on intentional programming of HEPA in each ASPs’ daily schedule, and includes a grocery store partnership to reduce price barriers to purchasing FV, professional development training to promote physical activity to develop core physical activity competencies, as well as ongoing technical support/assistance. Primary outcome measures include children’s accelerometry-derived MVPA and time spend sedentary while attending an ASP, direct observation of staff HEPA promoting and inhibiting behaviors, types of snacks served, and child consumption of snacks, as well as, cost of snacks via receipts and detailed accounting of intervention delivery costs to estimate cost-effectiveness. PMID:24893225

Project Report: Reducing Color Rivalry in Imagery for Conjugated Multiple Bandpass Filter Based Stereo Endoscopy

NASA Technical Reports Server (NTRS)

Ream, Allen

2011-01-01

A pair of conjugated multiple bandpass filters (CMBF) can be used to create spatially separated pupils in a traditional lens and imaging sensor system allowing for the passive capture of stereo video. This method is especially useful for surgical endoscopy where smaller cameras are needed to provide ample room for manipulating tools while also granting improved visualizations of scene depth. The significant issue in this process is that, due to the complimentary nature of the filters, the colors seen through each filter do not match each other, and also differ from colors as seen under a white illumination source. A color correction model was implemented that included optimized filter selection, such that the degree of necessary post-processing correction was minimized, and a chromatic adaptation transformation that attempted to fix the imaged colors tristimulus indices based on the principle of color constancy. Due to fabrication constraints, only dual bandpass filters were feasible. The theoretical average color error after correction between these filters was still above the fusion limit meaning that rivalry conditions are possible during viewing. This error can be minimized further by designing the filters for a subset of colors corresponding to specific working environments.

Improving signal-to-noise ratios of liquid chromatography-tandem mass spectrometry peaks using noise frequency spectrum modification between two consecutive matched-filtering procedures.

PubMed

Wang, Shau-Chun; Huang, Chih-Min; Chiang, Shu-Min

2007-08-17

This paper reports a simple chemometric technique to alter the noise spectrum of liquid chromatography-tandem mass spectrometry (LC-MS-MS) chromatogram between two consecutive matched filter procedures to improve the peak signal-to-noise (S/N) ratio enhancement. This technique is to multiply one match-filtered LC-MS-MS chromatogram with another artificial chromatogram added with thermal noises prior to the second matched filter. Because matched filter cannot eliminate low-frequency components inherent in the flicker noises of spike-like sharp peaks randomly riding on LC-MS-MS chromatograms, efficient peak S/N ratio improvement cannot be accomplished using one-step or consecutive matched filter procedures to process LC-MS-MS chromatograms. In contrast, when the match-filtered LC-MS-MS chromatogram is conditioned with the multiplication alteration prior to the second matched filter, much better efficient ratio improvement is achieved. The noise frequency spectrum of match-filtered chromatogram, which originally contains only low-frequency components, is altered to span a boarder range with multiplication operation. When the frequency range of this modified noise spectrum shifts toward higher frequency regime, the second matched filter, working as a low-pass filter, is able to provide better filtering efficiency to obtain higher peak S/N ratios. Real LC-MS-MS chromatograms containing random spike-like peaks, of which peak S/N ratio improvement is less than four times with two consecutive matched filters typically, are remedied to accomplish much better ratio enhancement approximately 16-folds when the noise frequency spectrum is modified between two matched filters.

Nonlocal variational model and filter algorithm to remove multiplicative noise

NASA Astrophysics Data System (ADS)

Chen, Dai-Qiang; Zhang, Hui; Cheng, Li-Zhi

2010-07-01

The nonlocal (NL) means filter proposed by Buades, Coll, and Morel (SIAM Multiscale Model. Simul. 4(2), 490-530, 2005), which makes full use of the redundancy information in images, has shown to be very efficient for image denoising with Gauss noise added. On the basis of the NL method and a striver to minimize the conditional mean-square error, we design a NL means filter to remove multiplicative noise, and combining the NL filter to regularity method, we propose a NL total variational (TV) model and present a fast iterated algorithm for it. Experiments demonstrate that our algorithm is better than TV method; it is superior in preserving small structures and textures and can obtain an improvement in peak signal-to-noise ratio.

Multiple sound source localization using gammatone auditory filtering and direct sound componence detection

NASA Astrophysics Data System (ADS)

Chen, Huaiyu; Cao, Li

2017-06-01

In order to research multiple sound source localization with room reverberation and background noise, we analyze the shortcomings of traditional broadband MUSIC and ordinary auditory filtering based broadband MUSIC method, then a new broadband MUSIC algorithm with gammatone auditory filtering of frequency component selection control and detection of ascending segment of direct sound componence is proposed. The proposed algorithm controls frequency component within the interested frequency band in multichannel bandpass filter stage. Detecting the direct sound componence of the sound source for suppressing room reverberation interference is also proposed, whose merits are fast calculation and avoiding using more complex de-reverberation processing algorithm. Besides, the pseudo-spectrum of different frequency channels is weighted by their maximum amplitude for every speech frame. Through the simulation and real room reverberation environment experiments, the proposed method has good performance. Dynamic multiple sound source localization experimental results indicate that the average absolute error of azimuth estimated by the proposed algorithm is less and the histogram result has higher angle resolution.

Implementation of High Time Delay Accuracy of Ultrasonic Phased Array Based on Interpolation CIC Filter.

PubMed

Liu, Peilu; Li, Xinghua; Li, Haopeng; Su, Zhikun; Zhang, Hongxu

2017-10-12

In order to improve the accuracy of ultrasonic phased array focusing time delay, analyzing the original interpolation Cascade-Integrator-Comb (CIC) filter, an 8× interpolation CIC filter parallel algorithm was proposed, so that interpolation and multichannel decomposition can simultaneously process. Moreover, we summarized the general formula of arbitrary multiple interpolation CIC filter parallel algorithm and established an ultrasonic phased array focusing time delay system based on 8× interpolation CIC filter parallel algorithm. Improving the algorithmic structure, 12.5% of addition and 29.2% of multiplication was reduced, meanwhile the speed of computation is still very fast. Considering the existing problems of the CIC filter, we compensated the CIC filter; the compensated CIC filter's pass band is flatter, the transition band becomes steep, and the stop band attenuation increases. Finally, we verified the feasibility of this algorithm on Field Programming Gate Array (FPGA). In the case of system clock is 125 MHz, after 8× interpolation filtering and decomposition, time delay accuracy of the defect echo becomes 1 ns. Simulation and experimental results both show that the algorithm we proposed has strong feasibility. Because of the fast calculation, small computational amount and high resolution, this algorithm is especially suitable for applications with high time delay accuracy and fast detection.

Tailoring noise frequency spectrum to improve NIR determinations.

PubMed

Xie, Shaofei; Xiang, Bingren; Yu, Liyan; Deng, Haishan

2009-12-15

Near infrared spectroscopy (NIR) contains excessive background noise and weak analytical signals caused by near infrared overtones and combinations. That makes it difficult to achieve quantitative determinations of low concentration samples by NIR. A simple chemometric approach has been established to modify the noise frequency spectrum to improve NIR determinations. The proposed method is to multiply one Savitzky-Golay filtered NIR spectrum with another reference spectrum added with thermal noises before the other Savitzky-Golay filter. Since Savitzky-Golay filter is a kind of low-pass filter and cannot eliminate low frequency components of NIR spectrum, using one step or two consecutive Savitzky-Golay filter procedures cannot improve the determination of NIR greatly. Meanwhile, significant improvement is achieved via the Savitzky-Golay filtered NIR spectrum processed with the multiplication alteration before the other Savitzky-Golay filter. The frequency range of the modified noise spectrum shifts toward higher frequency regime via multiplication operation. So the second Savitzky-Golay filter is able to provide better filtering efficiency to obtain satisfied result. The improvement of NIR determination with tailoring noise frequency spectrum technique was demonstrated by both simulated dataset and two measured NIR spectral datasets. It is expected that noise frequency spectrum technique will be adopted mostly in applications where quantitative determination of low concentration sample is crucial.

Nicotine, cotinine, and β-nicotyrine inhibit NNK-induced DNA-strand break in the hepatic cell line HepaRG.

PubMed

Ordonez, Patricia; Sierra, Ana Belen; Camacho, Oscar M; Baxter, Andrew; Banerjee, Anisha; Waters, David; Minet, Emmanuel

2014-07-15

Recent in vitro work using purified enzymes demonstrated that nicotine and/or a nicotine metabolite could inhibit CYPs (CYP2A6, 2A13, 2E1) involved in the metabolism of the genotoxic tobacco nitrosamine NNK. This observation raises the possibility of nicotine interaction with the mechanism of NNK bioactivation. Therefore, we hypothesized that nicotine or a nicotine metabolite such as cotinine might contribute to the inhibition of NNK-induced DNA strand breaks by interfering with CYP enzymes. The effect of nicotine and cotinine on DNA strand breaks was evaluated using the COMET assay in CYP competent HepaRG cells incubated with bioactive CYP-dependent NNK and CYP-independent NNKOAc (4-(acetoxymethylnitrosoamino)-1-(3-pyridyl)-1-butanone). We report a dose-dependent reduction in DNA damage in hepatic-derived cell lines in the presence of nicotine and cotinine. Those results are discussed in the context of the in vitro model selected. Copyright © 2014. Published by Elsevier Ltd.

Fuzzy adaptive interacting multiple model nonlinear filter for integrated navigation sensor fusion.

PubMed

Tseng, Chien-Hao; Chang, Chih-Wen; Jwo, Dah-Jing

2011-01-01

In this paper, the application of the fuzzy interacting multiple model unscented Kalman filter (FUZZY-IMMUKF) approach to integrated navigation processing for the maneuvering vehicle is presented. The unscented Kalman filter (UKF) employs a set of sigma points through deterministic sampling, such that a linearization process is not necessary, and therefore the errors caused by linearization as in the traditional extended Kalman filter (EKF) can be avoided. The nonlinear filters naturally suffer, to some extent, the same problem as the EKF for which the uncertainty of the process noise and measurement noise will degrade the performance. As a structural adaptation (model switching) mechanism, the interacting multiple model (IMM), which describes a set of switching models, can be utilized for determining the adequate value of process noise covariance. The fuzzy logic adaptive system (FLAS) is employed to determine the lower and upper bounds of the system noise through the fuzzy inference system (FIS). The resulting sensor fusion strategy can efficiently deal with the nonlinear problem for the vehicle navigation. The proposed FUZZY-IMMUKF algorithm shows remarkable improvement in the navigation estimation accuracy as compared to the relatively conventional approaches such as the UKF and IMMUKF.

Tailoring noise frequency spectrum between two consecutive second derivative filtering procedures to improve liquid chromatography-mass spectrometry determinations.

PubMed

Wang, Shau-Chun; Lin, Chiao-Juan; Chiang, Shu-Min; Yu, Sung-Nien

2008-03-15

This paper reports a simple chemometric technique to alter the noise spectrum of a liquid chromatography-mass spectrometry (LC-MS) chromatogram between two consecutive second-derivative filter procedures to improve the peak signal-to-noise (S/N) ratio enhancement. This technique is to multiply one second-derivative filtered LC-MS chromatogram with another artificial chromatogram added with thermal noises prior to the other second-derivative filter. Because the second-derivative filter cannot eliminate frequency components within its own filter bandwidth, more efficient peak S/N ratio improvement cannot be accomplished using consecutive second-derivative filter procedures to process LC-MS chromatograms. In contrast, when the second-derivative filtered LC-MS chromatogram is conditioned with the multiplication alteration prior to the other second-derivative filter, much better ratio improvement is achieved. The noise frequency spectrum of the second-derivative filtered chromatogram, which originally contains frequency components within the filter bandwidth, is altered to span a broader range with multiplication operation. When the frequency range of this modified noise spectrum shifts toward the other regimes, the other second-derivative filter, working as a band-pass filter, is able to provide better filtering efficiency to obtain higher peak S/N ratios. Real LC-MS chromatograms, of which 5-fold peak S/N ratio improvement achieved with two consecutive second-derivative filters remains the same S/N ratio improvement using a one-step second-derivative filter, are improved to accomplish much better ratio enhancement, approximately 25-fold or higher when the noise frequency spectrum is modified between two matched filters. The linear standard curve using the filtered LC-MS signals is validated. The filtered LC-MS signals are also more reproducible. The more accurate determinations of very low-concentration samples (S/N ratio about 5-7) are obtained via standard addition procedures using the filtered signals rather than the determinations using the original signals.

Fluence-field modulated x-ray CT using multiple aperture devices

NASA Astrophysics Data System (ADS)

Stayman, J. Webster; Mathews, Aswin; Zbijewski, Wojciech; Gang, Grace; Siewerdsen, Jeffrey; Kawamoto, Satomi; Blevis, Ira; Levinson, Reuven

2016-03-01

We introduce a novel strategy for fluence field modulation (FFM) in x-ray CT using multiple aperture devices (MADs). MAD filters permit FFM by blocking or transmitting the x-ray beam on a fine (0.1-1 mm) scale. The filters have a number of potential advantages over other beam modulation strategies including the potential for a highly compact design, modest actuation speed and acceleration requirements, and spectrally neutral filtration due to their essentially binary action. In this work, we present the underlying MAD filtration concept including a design process to achieve a specific class of FFM patterns. A set of MAD filters is fabricated using a tungsten laser sintering process and integrated into an x-ray CT test bench. A characterization of the MAD filters is conducted and compared to traditional attenuating bowtie filters and the ability to flatten the fluence profile for a 32 cm acrylic phantom is demonstrated. MAD-filtered tomographic data was acquired on the CT test bench and reconstructed without artifacts associated with the MAD filter. These initial studies suggest that MAD-based FFM is appropriate for integration in clinical CT system to create patient-specific fluence field profile and reduce radiation exposures.

Implementation of High Time Delay Accuracy of Ultrasonic Phased Array Based on Interpolation CIC Filter

PubMed Central

Liu, Peilu; Li, Xinghua; Li, Haopeng; Su, Zhikun; Zhang, Hongxu

2017-01-01

In order to improve the accuracy of ultrasonic phased array focusing time delay, analyzing the original interpolation Cascade-Integrator-Comb (CIC) filter, an 8× interpolation CIC filter parallel algorithm was proposed, so that interpolation and multichannel decomposition can simultaneously process. Moreover, we summarized the general formula of arbitrary multiple interpolation CIC filter parallel algorithm and established an ultrasonic phased array focusing time delay system based on 8× interpolation CIC filter parallel algorithm. Improving the algorithmic structure, 12.5% of addition and 29.2% of multiplication was reduced, meanwhile the speed of computation is still very fast. Considering the existing problems of the CIC filter, we compensated the CIC filter; the compensated CIC filter’s pass band is flatter, the transition band becomes steep, and the stop band attenuation increases. Finally, we verified the feasibility of this algorithm on Field Programming Gate Array (FPGA). In the case of system clock is 125 MHz, after 8× interpolation filtering and decomposition, time delay accuracy of the defect echo becomes 1 ns. Simulation and experimental results both show that the algorithm we proposed has strong feasibility. Because of the fast calculation, small computational amount and high resolution, this algorithm is especially suitable for applications with high time delay accuracy and fast detection. PMID:29023385

Comparative Biochemistry and Metabolism. Part 2. Naphthalene Lung Toxicity.

DTIC Science & Technology

1985-11-01

Metabolites to Intra- and Extracellular Proteins .............. ........ 18 Thiol Status in Isolated Hepatocytes Incubated with Naphthalene or Menadione ...Viabilities of isolated hepatocytes incubated with menadione and varying concentrations of n aphthalene...23 15 Intracellular reduced glutathione levels in hepa- tocytes incubated in the presence of menadione or varying concentrations of naphthalene

29 CFR 1926.1101 - Asbestos.

Code of Federal Regulations, 2010 CFR

2010-07-01

... circuit interrupters. (ii) Glove bag systems may be used to remove PACM and/or ACM from straight runs of.... (2) The HEPA vacuum cleaner or other device used to prevent collapse of bag during removal shall run... PACM from pipe runs with the following specifications and work practices. (A) Specifications: (1) Glove...

29 CFR 1926.1101 - Asbestos.

Code of Federal Regulations, 2013 CFR

2013-07-01

... circuit interrupters. (ii) Glove bag systems may be used to remove PACM and/or ACM from straight runs of.... (2) The HEPA vacuum cleaner or other device used to prevent collapse of bag during removal shall run... PACM from pipe runs with the following specifications and work practices. (A) Specifications: (1) Glove...

29 CFR 1926.1101 - Asbestos.

Code of Federal Regulations, 2012 CFR

2012-07-01

... circuit interrupters. (ii) Glove bag systems may be used to remove PACM and/or ACM from straight runs of.... (2) The HEPA vacuum cleaner or other device used to prevent collapse of bag during removal shall run... PACM from pipe runs with the following specifications and work practices. (A) Specifications: (1) Glove...

29 CFR 1926.1101 - Asbestos.

Code of Federal Regulations, 2014 CFR

2014-07-01

... circuit interrupters. (ii) Glove bag systems may be used to remove PACM and/or ACM from straight runs of.... (2) The HEPA vacuum cleaner or other device used to prevent collapse of bag during removal shall run... PACM from pipe runs with the following specifications and work practices. (A) Specifications: (1) Glove...

29 CFR 1926.1101 - Asbestos.

Code of Federal Regulations, 2011 CFR

2011-07-01

... circuit interrupters. (ii) Glove bag systems may be used to remove PACM and/or ACM from straight runs of.... (2) The HEPA vacuum cleaner or other device used to prevent collapse of bag during removal shall run... PACM from pipe runs with the following specifications and work practices. (A) Specifications: (1) Glove...

Working in a Vacuum

ERIC Educational Resources Information Center

Rathey, Allen

2005-01-01

In this article, the author discusses several myths about vacuum cleaners and offers tips on evaluating and purchasing this essential maintenance tool. These myths are: (1) Amps mean performance; (2) Everyone needs high-efficiency particulate air (HEPA): (3) Picking up a "bowling ball" shows cleaning power; (4) All vacuum bags are the same; (5)…

Arbitrary frequency tunable radio frequency bandpass filter based on nano-patterned Permalloy coplanar waveguide (invited)

NASA Astrophysics Data System (ADS)

Wang, Tengxing; Rahman, B. M. Farid; Peng, Yujia; Xia, Tian; Wang, Guoan

2015-05-01

A well designed coplanar waveguide (CPW) based center frequency tunable bandpass filter (BPF) at 4 GHz enabled with patterned Permalloy (Py) thin film has been implemented. The operating frequency of BPF is tunable with only DC current without the use of any external magnetic field. Electromagnetic bandgap resonators structure is adopted in the BPF and thus external DC current can be applied between the input and output of the filter for tuning of Py permeability. Special configurations of resonators with multiple narrow parallel sections have been considered for larger inductance tenability; the tunability of CPW transmission lines of different widths with patterned Py thin film on the top of the signal lines is compared and measured. Py thin film patterned as bars is deposited on the top of the multiple narrow parallel sections of the designed filter. No extra area is required for the designed filter configuration. Filter is measured and results show that its center frequency could be tuned from 4 GHz to 4.02 GHz when the DC current is applied from 0 mA to 400 mA.

Multiple point least squares equalization in a room

NASA Technical Reports Server (NTRS)

Elliott, S. J.; Nelson, P. A.

1988-01-01

Equalization filters designed to minimize the mean square error between a delayed version of the original electrical signal and the equalized response at a point in a room have previously been investigated. In general, such a strategy degrades the response at positions in a room away from the equalization point. A method is presented for designing an equalization filter by adjusting the filter coefficients to minimize the sum of the squares of the errors between the equalized responses at multiple points in the room and delayed versions of the original, electrical signal. Such an equalization filter can give a more uniform frequency response over a greater volume of the enclosure than can the single point equalizer above. Computer simulation results are presented of equalizing the frequency responses from a loudspeaker to various typical ear positions, in a room with dimensions and acoustic damping typical of a car interior, using the two approaches outlined above. Adaptive filter algorithms, which can automatically adjust the coefficients of a digital equalization filter to achieve this minimization, will also be discussed.

Endobronchial Forceps-Assisted and Excimer Laser-Assisted Inferior Vena Cava Filter Removal: The Data, Where We Are, and How It Is Done.

PubMed

Chen, James X; Montgomery, Jennifer; McLennan, Gordon; Stavropoulos, S William

2018-06-01

The recognition of inferior vena cava filter related complications has motivated increased attentiveness in clinical follow-up of patients with inferior vena cava filters and has led to development of multiple approaches for retrieving filters that are challenging or impossible to remove using conventional techniques. Endobronchial forceps and excimer lasers are tools for designed to aid in complex inferior vena cava filter removals. This article discusses endobronchial forceps-assisted and excimer laser-assisted inferior vena cava filter retrievals. Copyright © 2018 Elsevier Inc. All rights reserved.

VizieR Online Data Catalog: Photometry of multiple stars at NAOR&ASV in 2015 (Cvetkovic+, 2017)

NASA Astrophysics Data System (ADS)

Cvetkovic, Z.; Pavlovic, R.; Boeva, S.

2018-05-01

This is the ninth series of CCD observations of double and multiple stars, obtained at the Bulgarian National Astronomical Observatory at Rozhen (NAOR) over five nights. As previously, the CCD camera VersArray 1300B was used, which was attached to the 2 m telescope. For each double or multiple star, five CCD frames in the Johnson B filter and five frames in the Johnson V filter were taken, which enabled us to determine the magnitude difference for these filters. In 2015 at the Astronomical Station at Vidojevica (ASV), over a total of 23 nights, observations were carried out by using the 60 cm telescope with a Cassegrain optical system. This is the fourth observational series at ASV since the work started there in 2011. In the observations we used the Apogee Alta U42 CCD camera whose characteristics can be found in the paper by Cvetkovic et al. (2016, J/AJ/151/58). Every pair was observed five times in the Cousins/Bessel B filter and five times in the Cousins/Bessel V one. (3 data files).

SME filter approach to multiple target tracking with false and missing measurements

NASA Astrophysics Data System (ADS)

Lee, Yong J.; Kamen, Edward W.

1993-10-01

The symmetric measurement equation (SME) filter for track maintenance in multiple target tracking is extended to the general case when there are an arbitrary unknown number of false and missing position measurements in the measurement set at any time point. It is assumed that the number N of targets is known a priori and that the target motions consist of random perturbations of constant-velocity trajectories. The key idea in the paper is to generate a new measurement vector from sums-of-products of the elements of 'feasible' N-element data vectors that pass a thresholding operation in the sums-of-products framework. Via this construction, the data association problem is completely avoided, and in addition, there is no need to identify which target measurements may correspond to false returns or which target measurements may be missing. A computer simulation of SME filter performance is given, including a comparison with the associated filter (a benchmark) and the joint probabilistic data association (JPDA) filter.

Eridania Planitia - False Color

NASA Image and Video Library

2016-06-22

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of Eridania Planitia.

Makhambet Crater - False Color

NASA Image and Video Library

2015-01-29

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows Makhambet Crater.

Tyrrhena Terra - False Color

NASA Image and Video Library

2016-03-16

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows a hill in Tyrrhena Terra.

Gale Crater - False Color

NASA Image and Video Library

2016-10-17

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of Gale Crater.

Crater - False Color

NASA Image and Video Library

2016-03-07

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows an unnamed crater in Terra Sabaea.

Ophir Chasma - False Color

NASA Image and Video Library

2016-04-28

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of Ophir Chasma.

Terra Sirenum - False Color

NASA Image and Video Library

2016-03-14

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of Terra Sirenum.

Capri Mensa - False Color

NASA Image and Video Library

2016-03-18

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of Capri Mensa.

Peraea Cavus - False Color

NASA Image and Video Library

2016-05-02

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of Peraea Cavus.

Martin Crater - False Color

NASA Image and Video Library

2016-03-09

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of Martin Crater.

Nili Fossae - False Color

NASA Image and Video Library

2016-04-27

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of Nili Fossae.

Multiple Optical Filter Design Simulation Results

NASA Astrophysics Data System (ADS)

Mendelsohn, J.; Englund, D. C.

1986-10-01

In this paper we continue our investigation of the application of matched filters to robotic vision problems. Specifically, we are concerned with the tray-picking problem. Our principal interest in this paper is the examination of summation affects which arise from attempting to reduce the matched filter memory size by averaging of matched filters. While the implementation of matched filtering theory to applications in pattern recognition or machine vision is ideally through the use of optics and optical correlators, in this paper the results were obtained through a digital simulation of the optical process.

SAR Speckle Noise Reduction Using Wiener Filter

NASA Technical Reports Server (NTRS)

Joo, T. H.; Held, D. N.

1983-01-01

Synthetic aperture radar (SAR) images are degraded by speckle. A multiplicative speckle noise model for SAR images is presented. Using this model, a Wiener filter is derived by minimizing the mean-squared error using the known speckle statistics. Implementation of the Wiener filter is discussed and experimental results are presented. Finally, possible improvements to this method are explored.

Renaudot Crater - False Color

NASA Image and Video Library

2015-01-15

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Renaudot Crater.

Terra Sirenum - False Color

NASA Image and Video Library

2016-04-25

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of the plains of Terra Sirenum.

Arabia Terra - False Color

NASA Image and Video Library

2016-05-05

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of the plains of Arabia Terra.

Granicus Valles - False Color

NASA Image and Video Library

2015-01-12

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Granicus Valles.

Candor Labes - False Color

NASA Image and Video Library

2014-12-25

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Candor Labes.

Coprates Chasma - False Color

NASA Image and Video Library

2015-01-08

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Coprates Chasma.

Terra Sirenum - False Color

NASA Image and Video Library

2016-03-15

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of the plains of Terra Sirenum.

Terra Sirenum - False Color

NASA Image and Video Library

2016-05-06

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of the plains of Terra Sirenum.

Windstreaks -- False Color

NASA Image and Video Library

2015-01-30

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows windstreaks in Daedalia Planum.

Nili Patera - False Color

NASA Image and Video Library

2015-01-02

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Nili Patera.

Syrtis Major Planum - False Color

NASA Image and Video Library

2016-09-09

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of Syrtis Major Planum.

Atlantis Chaos - False Color

NASA Image and Video Library

2014-12-23

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Atlantis Chaos.

Coprates Chasma - False Color

NASA Image and Video Library

2016-03-11

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of the floor of Coprates Chasma.

Coprates Chasma - False Color

NASA Image and Video Library

2015-01-01

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Coprates Chasma.

Terra Sabaea - False Color

NASA Image and Video Library

2016-03-08

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of the plains of Terra Sabaea.

Hargraves Crater - False Color

NASA Image and Video Library

2015-01-13

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Hargraves Crater.

Reull Vallis - False Color

NASA Image and Video Library

2014-12-18

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Reull Vallis.

Simultaneous imaging of cellular morphology and multiple biomarkers using an acousto-optic tunable filter-based bright field microscope.

PubMed

Wachman, Elliot S; Geyer, Stanley J; Recht, Joel M; Ward, Jon; Zhang, Bill; Reed, Murray; Pannell, Chris

2014-05-01

An acousto-optic tunable filter (AOTF)-based multispectral imaging microscope system allows the combination of cellular morphology and multiple biomarker stainings on a single microscope slide. We describe advances in AOTF technology that have greatly improved spectral purity, field uniformity, and image quality. A multispectral imaging bright field microscope using these advances demonstrates pathology results that have great potential for clinical use.

Real-time Java simulations of multiple interference dielectric filters

NASA Astrophysics Data System (ADS)

Kireev, Alexandre N.; Martin, Olivier J. F.

2008-12-01

An interactive Java applet for real-time simulation and visualization of the transmittance properties of multiple interference dielectric filters is presented. The most commonly used interference filters as well as the state-of-the-art ones are embedded in this platform-independent applet which can serve research and education purposes. The Transmittance applet can be freely downloaded from the site http://cpc.cs.qub.ac.uk. Program summaryProgram title: Transmittance Catalogue identifier: AEBQ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEBQ_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 5778 No. of bytes in distributed program, including test data, etc.: 90 474 Distribution format: tar.gz Programming language: Java Computer: Developed on PC-Pentium platform Operating system: Any Java-enabled OS. Applet was tested on Windows ME, XP, Sun Solaris, Mac OS RAM: Variable Classification: 18 Nature of problem: Sophisticated wavelength selective multiple interference filters can include some tens or even hundreds of dielectric layers. The spectral response of such a stack is not obvious. On the other hand, there is a strong demand from application designers and students to get a quick insight into the properties of a given filter. Solution method: A Java applet was developed for the computation and the visualization of the transmittance of multilayer interference filters. It is simple to use and the embedded filter library can serve educational purposes. Also, its ability to handle complex structures will be appreciated as a useful research and development tool. Running time: Real-time simulations

FIR Filter of DS-CDMA UWB Modem Transmitter

NASA Astrophysics Data System (ADS)

Kang, Kyu-Min; Cho, Sang-In; Won, Hui-Chul; Choi, Sang-Sung

This letter presents low-complexity digital pulse shaping filter structures of a direct sequence code division multiple access (DS-CDMA) ultra wide-band (UWB) modem transmitter with a ternary spreading code. The proposed finite impulse response (FIR) filter structures using a look-up table (LUT) have the effect of saving the amount of memory by about 50% to 80% in comparison to the conventional FIR filter structures, and consequently are suitable for a high-speed parallel data process.

An information-theoretic approach to motor action decoding with a reconfigurable parallel architecture.

PubMed

Craciun, Stefan; Brockmeier, Austin J; George, Alan D; Lam, Herman; Príncipe, José C

2011-01-01

Methods for decoding movements from neural spike counts using adaptive filters often rely on minimizing the mean-squared error. However, for non-Gaussian distribution of errors, this approach is not optimal for performance. Therefore, rather than using probabilistic modeling, we propose an alternate non-parametric approach. In order to extract more structure from the input signal (neuronal spike counts) we propose using minimum error entropy (MEE), an information-theoretic approach that minimizes the error entropy as part of an iterative cost function. However, the disadvantage of using MEE as the cost function for adaptive filters is the increase in computational complexity. In this paper we present a comparison between the decoding performance of the analytic Wiener filter and a linear filter trained with MEE, which is then mapped to a parallel architecture in reconfigurable hardware tailored to the computational needs of the MEE filter. We observe considerable speedup from the hardware design. The adaptation of filter weights for the multiple-input, multiple-output linear filters, necessary in motor decoding, is a highly parallelizable algorithm. It can be decomposed into many independent computational blocks with a parallel architecture readily mapped to a field-programmable gate array (FPGA) and scales to large numbers of neurons. By pipelining and parallelizing independent computations in the algorithm, the proposed parallel architecture has sublinear increases in execution time with respect to both window size and filter order.

From cell lines to tissues: extrapolation of transcriptional effects to human tissues (SOT)

EPA Science Inventory

A new suite of assays in the metabolically-competent, human hepatocyte-derived HepaRG cell line has been added to the ToxCast screening suite. For 1066 chemicals we have evaluated the chemical treatment-induced changes in expression for a diverse set of 93 genes representative of...

Social Support for Exercise and Dietary Habits among College Students

ERIC Educational Resources Information Center

Gruber, Kenneth J.

2008-01-01

An assessment inventory (the Friend/Peer Support-Health Eating Physical Activity Scale-FPS-HEPAS) was developed to measure social influence patterns of college student physical activity and food consumption habits. Principal components analysis of 50 items with two referent sets (friends and peers) produced two scales with common factors:…

TOXICITY PROFILES IN RATS TREATED WITH TUMORIGENIC AND NONTUMORIGENIC TRIAZOLE CONAZOLE FUNGICIDES: PROPICONAZOLE, TRIADIMEFON, AND MYCLOBUTANIL

EPA Science Inventory

Conazoles are a class of azole based fungicides used in agriculture and as pharmaceutical products. They have a common mode of antifungal action through inhibition of ergosterol biosynthesis. Some members of this class have been shown to be hepatotoxic and will induce mouse hepa...

Extraction methods determine the antioxidant capacity and induction of quinone reductase by soy products in vitro

USDA-ARS?s Scientific Manuscript database

Gastrointestinal mimic (GI) and organic solvent extracts of whole soybean powder (WSP), soy protein concentrate (SPC), and soy protein isolate (SPI) as well as soy isoflavone concentrate (SIC) were analyzed for total phenols; quinone reductase (QR) induction in hepa1c1c7 cells; antioxidant scavengi...

Evaluation of an Enhanced Bank of Kalman Filters for In-Flight Aircraft Engine Sensor Fault Diagnostics

NASA Technical Reports Server (NTRS)

Kobayashi, Takahisa; Simon, Donald L.

2004-01-01

In this paper, an approach for in-flight fault detection and isolation (FDI) of aircraft engine sensors based on a bank of Kalman filters is developed. This approach utilizes multiple Kalman filters, each of which is designed based on a specific fault hypothesis. When the propulsion system experiences a fault, only one Kalman filter with the correct hypothesis is able to maintain the nominal estimation performance. Based on this knowledge, the isolation of faults is achieved. Since the propulsion system may experience component and actuator faults as well, a sensor FDI system must be robust in terms of avoiding misclassifications of any anomalies. The proposed approach utilizes a bank of (m+1) Kalman filters where m is the number of sensors being monitored. One Kalman filter is used for the detection of component and actuator faults while each of the other m filters detects a fault in a specific sensor. With this setup, the overall robustness of the sensor FDI system to anomalies is enhanced. Moreover, numerous component fault events can be accounted for by the FDI system. The sensor FDI system is applied to a commercial aircraft engine simulation, and its performance is evaluated at multiple power settings at a cruise operating point using various fault scenarios.

Research on signal processing of shock absorber test bench based on zero-phase filter

NASA Astrophysics Data System (ADS)

Wu, Yi; Ding, Guoqing

2017-10-01

The quality of force-displacement diagram is significant to help evaluate the performance of shock absorbers. Damping force sampling data is often interfered by Gauss white noise, 50Hz power interference and its harmonic wave during the process of testing; data de-noising has become the core problem of drawing true, accurate and real-time indicator diagram. The noise and interference can be filtered out through generic IIR or FIR low-pass filter, but addition phase lag of useful signal will be caused due to the inherent attribute of IIR and FIR filter. The paper uses FRR method to realize zero-phase digital filtering in a software way based on mutual cancellation of phase lag between the forward and reverse sequences after through the filter. High-frequency interference above 40Hz are filtered out completely and noise attenuation is more than -40dB, with no additional phase lag. The method is able to restore the true signal as far as possible. Theoretical simulation and practical test indicate high-frequency noises have been effectively inhibited in multiple typical speed cases, signal-to-noise ratio being greatly improved; the curve in indicator diagram has better smoothness and fidelity. The FRR algorithm has low computational complexity, fast running time, and can be easily transplanted in multiple platforms.

The histone deacetylase inhibiting drug Entinostat induces lipid accumulation in differentiated HepaRG cells

NASA Astrophysics Data System (ADS)

Nunn, Abigail D. G.; Scopigno, Tullio; Pediconi, Natalia; Levrero, Massimo; Hagman, Henning; Kiskis, Juris; Enejder, Annika

2016-06-01

Dietary overload of toxic, free metabolic intermediates leads to disrupted insulin signalling and fatty liver disease. However, it was recently reported that this pathway might not be universal: depletion of histone deacetylase (HDAC) enhances insulin sensitivity alongside hepatic lipid accumulation in mice, but the mechanistic role of microscopic lipid structure in this effect remains unclear. Here we study the effect of Entinostat, a synthetic HDAC inhibitor undergoing clinical trials, on hepatic lipid metabolism in the paradigmatic HepaRG liver cell line. Specifically, we statistically quantify lipid droplet morphology at single cell level utilizing label-free microscopy, coherent anti-Stokes Raman scattering, supported by gene expression. We observe Entinostat efficiently rerouting carbohydrates and free-fatty acids into lipid droplets, upregulating lipid coat protein gene Plin4, and relocating droplets nearer to the nucleus. Our results demonstrate the power of Entinostat to promote lipid synthesis and storage, allowing reduced systemic sugar levels and sequestration of toxic metabolites within protected protein-coated droplets, suggesting a potential therapeutic strategy for diseases such as diabetes and metabolic syndrome.

Temporary Inferior Vena Cava Filters: How Do We Move Forward?

PubMed

Arous, Edward J; Messina, Louis M

2016-05-01

Despite their widespread use, the indications for the selective use of temporary inferior vena cava (IVC) filters remains uncertain with few trials supporting their use. Additionally, the risks of long-term temporary IVC filter insertion are being increasingly discussed amongst the mainstream media and through multiple class action lawsuits. Retrievable IVC filters were specifically designed to have a less secure implantation in order to facilitate retrieval. However, multiple reports have demonstrated significant filter-related complications, most commonly related to duration of implantation. Furthermore, the risk is not isolated to one manufacturer alone. The incidence of filter-related complications is linearly related to its duration of time on the market. Currently, the FDA recommends that IVC filters be removed within 25-54 days of their implantation. Unfortunately, little evidence exists to show that this recommendation is followed routinely. Recently, the PRESERVE Trial (NCT02381509) was initiated as a multicenter non-randomized open label study to determine the safety and effectiveness of commercially available IVC filters (both temporary and permanent) in individuals who require mechanical prophylaxis against pulmonary embolism. Until such evidence is developed, temporary IVC filters should be implanted based on best available evidence and routinely removed within the guidelines of the FDA of 25-54 days. A fair question at this point is whether the design features themselves that are required to manufacture a low profile removable IVC filter can achieve effective prophylaxis against pulmonary embolism at a low rate of short and long-term complications. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

FAST TRACK PAPER: Non-iterative multiple-attenuation methods: linear inverse solutions to non-linear inverse problems - II. BMG approximation

NASA Astrophysics Data System (ADS)

Ikelle, Luc T.; Osen, Are; Amundsen, Lasse; Shen, Yunqing

2004-12-01

The classical linear solutions to the problem of multiple attenuation, like predictive deconvolution, τ-p filtering, or F-K filtering, are generally fast, stable, and robust compared to non-linear solutions, which are generally either iterative or in the form of a series with an infinite number of terms. These qualities have made the linear solutions more attractive to seismic data-processing practitioners. However, most linear solutions, including predictive deconvolution or F-K filtering, contain severe assumptions about the model of the subsurface and the class of free-surface multiples they can attenuate. These assumptions limit their usefulness. In a recent paper, we described an exception to this assertion for OBS data. We showed in that paper that a linear and non-iterative solution to the problem of attenuating free-surface multiples which is as accurate as iterative non-linear solutions can be constructed for OBS data. We here present a similar linear and non-iterative solution for attenuating free-surface multiples in towed-streamer data. For most practical purposes, this linear solution is as accurate as the non-linear ones.

The magnitude and relevance of the February 2014 radiation release from the Waste Isolation Pilot Plant repository in New Mexico, USA.

PubMed

Thakur, P; Lemons, B G; White, C R

2016-09-15

After almost fifteen years of successful waste disposal operations, the first unambiguous airborne radiation release from the Waste Isolation Pilot Plant (WIPP) was detected beyond the site boundary on February 14, 2014. It was the first accident of its kind in the 15-year operating history of the WIPP. The accident released moderate levels of radioactivity into the underground air. A small but measurable amount of radioactivity also escaped to the surface through the ventilation system and was detected above ground. The dominant radionuclides released were americium and plutonium, in a ratio consistent with the known content of a breached drum. The radiation release was caused by a runaway chemical reaction inside a transuranic (TRU) waste drum which experienced a seal and lid failure, spewing radioactive materials into the repository. According to source-term estimation, approximately 2 to 10Ci of radioactivity was released from the breached drum into the underground, and an undetermined fraction of that source term became airborne, setting off an alarm and triggering the closure of seals designed to force exhausting air through a system of filters including high-efficiency-particulate-air (HEPA) filters. Air monitoring across the WIPP site intensified following the first reports of radiation detection underground to determine the extent of impact to WIPP personnel, the public, and the environment, if any. This article attempts to compile and interpret analytical data collected by an independent monitoring program conducted by the Carlsbad Environmental Monitoring & Research Center (CEMRC) and by a compliance-monitoring program conducted by the WIPP's management and operating contractor, the Nuclear Waste Partnership (NWP), LLC., in response to the accident. Both the independent and the WIPP monitoring efforts concluded that the levels detected were very low and localized, and no radiation-related health effects among local workers or the public would be expected. Published by Elsevier B.V.

Enhanced Characterization of Microorganisms in the Spacecraft Environment

NASA Technical Reports Server (NTRS)

Cruz, Patricia; Stetzenbach, Linda D.

2004-01-01

Spacecraft such as the International Space Station (ISS) and the space shuttles are enclosed environments where crewmembers may spend long periods of time. Currently, crewmembers spend approximately a period of 6 months in the ISS. It is known that these prolonged stays in space may result in weakening of the immune system. Therefore, exposure to opportunistic pathogens or high concentrations of environmental microorganisms may compromise the health of the crew. The detection of biocontaminants in spacecraft environments utilizes culture-based methodology, omitting greater than 90% of all microorganisms including pathogens such as Legionella and Cryptosporidium. Culturable bacteria and fungi have been the only allergens studied; the more potent allergens, such as those from dust mites, have never been tested for in spacecraft environments. In addition, no attempts have been made to monitor microbial toxins in spacecrafts. The present study utilized quantitative polymerase chain reaction (QPCR) as a novel approach for monitoring microorganisms in the spacecraft environment. QPCR is a molecular biology technique that does not rely on the physiological state of the organisms for identification, thereby enabling detection of both culturable and non-culturable organisms. In this project, specific molecular primers and probes were utilized for the detection and quantitation of two fungi of concern in indoor environments, Aspergillus fumigatus and Stachybotrys chartarum. These organisms were selected because of the availability of PCR primers and probes, and to establish the sample processing and analysis methodology that may be employed with additional organisms. Purification methods and QPCR assays were optimized for the detection of these organisms in air, surface, and water; and sample processing and analysis protocols were developed. Preliminary validation of these protocols was conducted in the laboratory with air, surface, and water samples seeded with known concentrations of the target organisms. Additional studies were conducted with bulk materials (HEPA filter pleats and particulate found on the filter screen) obtained from the ISS.

White blood cell DNA adducts in a cohort of asthmatic children exposed to environmental tobacco smoke

PubMed Central

Talaska, Glenn; Kahn, Robert S.; Schumann, Brenda; Khoury, Jane; Leonard, Anthony C.; Lanphear, Bruce P.

2010-01-01

Purpose Exposure to environmental tobacco smoke (ETS) leads to molecular damage in the form of DNA adducts. While lung cancer risk is higher among African Americans compared to White Americans, a few studies have tested for racial differences in DNA adducts among children exposed to ETS. The purpose of this study was to test whether African American children have higher DNA adducts levels compared to White children adjusted for ETS exposure. Methods Data and biologic specimens were drawn from an existing cohort of 212 asthmatic children. These subjects participated in a 12-month ETS-reduction trial that employed HEPA air cleaners with active filter cartridges and sham filter cartridges. White blood cell (WBC) DNA was analyzed for DNA adducts using 32P-postlabeling. We assessed ETS exposure using a validated air nicotine dosimeter. We determined the independent relationship between African American race and DNA adduct levels adjusted for ETS exposure and air cleaner use. Results The mean age of the subjects was 8.4 years; 55% were African American. There was no difference in DNA adduct levels between African American and White children (11.8 vs. 11.2 adducts per 109 nucleotides, p = 0.86), despite slightly higher levels of air nicotine exposure (3.4 vs. 2.2 μg/m3, p = 0.14). African American children used their air cleaners less often than White children. We found that the best predictor of DNA adduct levels was the duration of air cleaner use (r = −0.133, p = 0.056). This association was independent of cartridge type. Conclusions We did not see differences in adduct levels by race even after accounting for the level of ETS exposure. However, there was a marginal inverse association between air cleaner use and adducts. Additional research is required to understand this phenomenon. PMID:20336464

Revolutionary advances in medical waste management. The Sanitec system.

PubMed

Edlich, Richard F; Borel, Lise; Jensen, H Gordon; Winters, Kathryne L; Long, William B; Gubler, K Dean; Buschbacher, Ralph M; Becker, Daniel G; Chang, Dillon E; Korngold, Jonathan; Chitwood, W Randolph; Lin, Kant Y; Nichter, Larry S; Berenson, Susan; Britt, L D; Tafel, John A

2006-01-01

It is the purpose of this collective review to provide a detailed outline of a revolutionary medical waste disposal system that should be used in all medical centers in the world to prevent pollution of our planet from medical waste. The Sanitec medical waste disposal system consists of the following seven components: (1) an all-weather steel enclosure of the waste management system, allowing it to be used inside or outside of the hospital center; (2) an automatic mechanical lift-and-load system that protects the workers from devastating back injuries; (3) a sophisticated shredding system designed for medical waste; (4) a series of air filters including the High Efficiency Particulate Air (HEPA) filter; (5) microwave disinfection of the medical waste material; (6) a waste compactor or dumpster; and (7) an onboard microprocessor. It must be emphasized that this waste management system can be used either inside or outside the hospital. From start to finish, the Sanitec Microwave Disinfection system is designed to provide process and engineering controls that assure complete disinfection and destruction, while minimizing the operator's exposure to risk. There are numerous technologic benefits to the Sanitec systems, including environmental, operational, physical, and disinfection efficiency as well as waste residue disinfection. Wastes treated through the Sanitec system are thoroughly disinfected, unrecognizable, and reduced in volume by approximately 80% (saving valuable landfill space and reducing hauling requirements and costs). They are acceptable in any municipal solid waste program. Sanitec's Zero Pollution Advantage is augmented by a complete range of services, including installation, startup, testing, training, maintenance, and repair, over the life of this system. The Sanitec waste management system has essentially been designed to provide the best overall solution to the customer, when that customer actually looks at the total cost of dealing with the medical waste issue. The Sanitec system is the right choice for healthcare and medical waste professionals around the world.

Applications Where Snap is BPM for Radioactive Waste Assay

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

Miller, T.J.

2008-07-01

Historically, the Atomic Weapons Establishment (AWE) at Aldermaston in the United Kingdom (UK), has used a variety of assay techniques to measure the radioactive content of a diverse range of waste packages from decommissioning, operational and legacy sources. The regulator, the Environment Agency in the UK, places conditions and limits on AWE through an authorisation within the Radioactive Substances Act (RSA93). The conditions and limits require Best Practical Means (BPM) measurements to be used to demonstrate compliance with the authorisation. Hence, the assay technique employed needs to achieve a balance between risk of exposure, environmental considerations, technological considerations, health andmore » safety considerations and cost effectiveness, without being grossly disproportionate in terms of money, time or trouble. Recently published work has concluded that the Spectral Non-destructive Assay Platform (SNAP) assay system is BPM for Depleted Uranium (DU) waste assay at AWE (1) and low level plutonium in soft drummed waste, HEPA filters and soils (2-4). The purpose of this paper is to highlight other applications where SNAP represents BPM for radioactive waste assay. This has been done by intercomparison studies of SNAP with other assay techniques, such as Segmented Gamma Scanner (SGS) and Passive Neutron Coincidence Counter (PNCC). It has been concluded that, for a large range of waste packages encountered at AWE, SNAP is BPM. (author)« less

Evaluation of transmission risks associated with in vivo replication of several high containment pathogens in a biosafety level 4 laboratory

PubMed Central

Alimonti, Judie; Leung, Anders; Jones, Shane; Gren, Jason; Qiu, Xiangguo; Fernando, Lisa; Balcewich, Brittany; Wong, Gary; Ströher, Ute; Grolla, Allen; Strong, James; Kobinger, Gary

2014-01-01

Containment level 4 (CL4) laboratories studying biosafety level 4 viruses are under strict regulations to conduct nonhuman primate (NHP) studies in compliance of both animal welfare and biosafety requirements. NHPs housed in open-barred cages raise concerns about cross-contamination between animals, and accidental exposure of personnel to infectious materials. To address these concerns, two NHP experiments were performed. One examined the simultaneous infection of 6 groups of NHPs with 6 different viruses (Machupo, Junin, Rift Valley Fever, Crimean-Congo Hemorrhagic Fever, Nipah and Hendra viruses). Washing personnel between handling each NHP group, floor to ceiling biobubble with HEPA filter, and plexiglass between cages were employed for partial primary containment. The second experiment employed no primary containment around open barred cages with Ebola virus infected NHPs 0.3 meters from naïve NHPs. Viral antigen-specific ELISAs, qRT-PCR and TCID50 infectious assays were utilized to determine antibody levels and viral loads. No transmission of virus to neighbouring NHPs was observed suggesting limited containment protocols are sufficient for multi-viral CL4 experiments within one room. The results support the concept that Ebola virus infection is self-contained in NHPs infected intramuscularly, at least in the present experimental conditions, and is not transmitted to naïve NHPs via an airborne route. PMID:25059478

Evaluation of transmission risks associated with in vivo replication of several high containment pathogens in a biosafety level 4 laboratory.

PubMed

Alimonti, Judie; Leung, Anders; Jones, Shane; Gren, Jason; Qiu, Xiangguo; Fernando, Lisa; Balcewich, Brittany; Wong, Gary; Ströher, Ute; Grolla, Allen; Strong, James; Kobinger, Gary

2014-07-25

Containment level 4 (CL4) laboratories studying biosafety level 4 viruses are under strict regulations to conduct nonhuman primate (NHP) studies in compliance of both animal welfare and biosafety requirements. NHPs housed in open-barred cages raise concerns about cross-contamination between animals, and accidental exposure of personnel to infectious materials. To address these concerns, two NHP experiments were performed. One examined the simultaneous infection of 6 groups of NHPs with 6 different viruses (Machupo, Junin, Rift Valley Fever, Crimean-Congo Hemorrhagic Fever, Nipah and Hendra viruses). Washing personnel between handling each NHP group, floor to ceiling biobubble with HEPA filter, and plexiglass between cages were employed for partial primary containment. The second experiment employed no primary containment around open barred cages with Ebola virus infected NHPs 0.3 meters from naïve NHPs. Viral antigen-specific ELISAs, qRT-PCR and TCID50 infectious assays were utilized to determine antibody levels and viral loads. No transmission of virus to neighbouring NHPs was observed suggesting limited containment protocols are sufficient for multi-viral CL4 experiments within one room. The results support the concept that Ebola virus infection is self-contained in NHPs infected intramuscularly, at least in the present experimental conditions, and is not transmitted to naïve NHPs via an airborne route.

Invasive Aspergillosis in Hematological Patients.

PubMed

Kimura, Shun-Ichi

2016-01-01

Invasive aspergillosis (IA) is still one of the leading causes of morbidity and mortality in hematological patients, although its outcome has been improving. Prolonged and profound neutropenia in patients receiving intensive chemotherapy for acute leukemia and stem cell transplantation is a major risk factor for IA. Allogeneic stem cell transplant recipients with graft-versus-host disease and corticosteroid use are also at high risk. Management in a protective environment with high efficiency particular air (HEPA) filter is generally recommended to prevent aspergillosis in patients with prolonged and profound neutropenia. Antifungal prophylaxis against Aspergillus species should be considered in patients with past history of aspergillosis or colonization of Aspergillus species, at facilities with high incidence of IA and those without a protective environment. Early diagnosis and prompt antifungal treatment is important to improve outcome. Imaging studies such as computed tomography and biomarkers such as galactomannan antigen and β-D-glucan are useful for early diagnosis. Empirical antifungal treatment based on persistent or recurrent fever during neutropenia despite broad-spectrum antibiotic therapy is generally recommended in high-risk patients. Alternatively, a preemptive treatment strategy has recently been proposed in the context of progress in the early diagnosis of IA based on the results of imaging studies and biomarkers. Voriconazole is recommended for initial therapy for IA. Liposomal amphotericin B is considered as alternative initial therapy. Combination antifungal therapy of echinocandin with voriconazole or liposomal amphotericin B could be a choice for refractory cases.

Prediction of in vivo hepatotoxicity effects using in vitro ...

EPA Pesticide Factsheets

High-throughput in vitro transcriptomics data support molecular understanding of chemical-induced toxicity. Here, we evaluated the utility of such data to predict liver toxicity. First, in vitro gene expression data for 93 genes was generated following exposure of metabolically competent HepaRG cells to 1060 environmental chemicals from the US EPA ToxCast library. The empirical relationship between these data and rat chronic liver endpoints from animal studies in the Toxicity Reference Database (ToxRefDB) was then evaluated using machine learning techniques. Chemicals were classified as positive (242) or negative (135) based on observed hepatic histopathologic effects, and divided into three categories: hypertrophy (183), injury (112) and proliferative lesions (101). Hepatotoxicants were classified on the basis of the bioactivity of 93 genes (descriptors) using six machine learning algorithms: linear discriminant analysis, naïve Bayes, support vector classification, classification and regression trees, k-nearest neighbors, and an ensemble of classifiers. Classification performance was evaluated using 10-fold cross-validation testing, and in-loop, filter-based, feature subset selection. The best balanced accuracy for prediction of hypertrophy, injury and proliferative lesions were 0.81 ± 0.07, 0.79 ± 0.08 and 0.77 ± 0.09, respectively. Gene specific perturbation of xenobiotic metabolism enzymes (CYP7A1/2E1/4A11/1A1/4A22) and transporters (ABCG2, ABCB11, SLC22

The Time-Domain Matched Filter and the Spectral-Domain Matched Filter in 1-Dimensional NMR Spectroscopy.

PubMed

Spencer, Richard G

2010-09-01

A type of "matched filter" (MF), used extensively in the processing of one-dimensional spectra, is defined by multiplication of a free-induction decay (FID) by a decaying exponential with the same time constant as that of the FID. This maximizes, in a sense to be defined, the signal-to-noise ratio (SNR) in the spectrum obtained after Fourier transformation. However, a different entity known also as the matched filter was introduced by van Vleck in the context of pulse detection in the 1940's and has become widely integrated into signal processing practice. These two types of matched filters appear to be quite distinct. In the NMR case, the "filter", that is, the exponential multiplication, is defined by the characteristics of, and applied to, a time domain signal in order to achieve improved SNR in the spectral domain. In signal processing, the filter is defined by the characteristics of a signal in the spectral domain, and applied in order to improve the SNR in the temporal (pulse) domain. We reconcile these two distinct implementations of the matched filter, demonstrating that the NMR "matched filter" is a special case of the matched filter more rigorously defined in the signal processing literature. In addition, two limitations in the use of the MF are highlighted. First, application of the MF distorts resonance ratios as defined by amplitudes, although not as defined by areas. Second, the MF maximizes SNR with respect to resonance amplitude, while intensities are often more appropriately defined by areas. Maximizing the SNR with respect to area requires a somewhat different approach to matched filtering.

An efficient implementation of a high-order filter for a cubed-sphere spectral element model

NASA Astrophysics Data System (ADS)

Kang, Hyun-Gyu; Cheong, Hyeong-Bin

2017-03-01

A parallel-scalable, isotropic, scale-selective spatial filter was developed for the cubed-sphere spectral element model on the sphere. The filter equation is a high-order elliptic (Helmholtz) equation based on the spherical Laplacian operator, which is transformed into cubed-sphere local coordinates. The Laplacian operator is discretized on the computational domain, i.e., on each cell, by the spectral element method with Gauss-Lobatto Lagrange interpolating polynomials (GLLIPs) as the orthogonal basis functions. On the global domain, the discrete filter equation yielded a linear system represented by a highly sparse matrix. The density of this matrix increases quadratically (linearly) with the order of GLLIP (order of the filter), and the linear system is solved in only O (Ng) operations, where Ng is the total number of grid points. The solution, obtained by a row reduction method, demonstrated the typical accuracy and convergence rate of the cubed-sphere spectral element method. To achieve computational efficiency on parallel computers, the linear system was treated by an inverse matrix method (a sparse matrix-vector multiplication). The density of the inverse matrix was lowered to only a few times of the original sparse matrix without degrading the accuracy of the solution. For better computational efficiency, a local-domain high-order filter was introduced: The filter equation is applied to multiple cells, and then the central cell was only used to reconstruct the filtered field. The parallel efficiency of applying the inverse matrix method to the global- and local-domain filter was evaluated by the scalability on a distributed-memory parallel computer. The scale-selective performance of the filter was demonstrated on Earth topography. The usefulness of the filter as a hyper-viscosity for the vorticity equation was also demonstrated.

Crawler Solids Unknown Analysis

NASA Technical Reports Server (NTRS)

Frandsen, Athela

2016-01-01

Crawler Transporter (CT) #2 has been undergoing refurbishment to carry the Space Launch System (SLS). After returning to normal operation, multiple filters of the gear box lubrication system failed/clogged and went on bypass during a test run to the launch pad. Analysis of the filters was done in large part with polarized light microscopy (PLM) to identify the filter contaminates and the source of origin.

Ares Vallis - False Color

NASA Image and Video Library

2014-12-31

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of of Ares Vallis.

Coprates Chasma - False Color

NASA Image and Video Library

2014-12-10

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image captured by NASA 2001 Mars Odyssey spacecraft shows part of Coprates Chasma.

Mawrth Vallis - False Color

NASA Image and Video Library

2015-09-30

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows where Mawrth Vallis empties into Chryse Planitia.

Utopia Planitia - False Color

NASA Image and Video Library

2015-01-20

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows an unnamed crater in Utopia Planitia.

Hebes Chasma - False Color

NASA Image and Video Library

2014-12-08

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image captured by NASA 2001 Mars Odyssey spacecraft shows part of Hebes Chasma.

Crater - False Color

NASA Image and Video Library

2015-01-14

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows an unnamed crater in Acidalia Planitia.

Kasei Valles - False Color

NASA Image and Video Library

2015-01-07

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows a portion of Kasei Vallis.

Yuty Crater Ejecta - False Color

NASA Image and Video Library

2016-04-26

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of the ejecta from Yuty Crater.

Terra Sabaea - False Color

NASA Image and Video Library

2016-02-01

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image captured by NASA 2001 Mars Odyssey spacecraft shows part of the plains of Terra Sabaea.

Melas Chasma - False Color

NASA Image and Video Library

2014-12-09

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image captured by NASA 2001 Mars Odyssey spacecraft shows part of Melas Chasma.

Coprates Chasma - False Color

NASA Image and Video Library

2014-12-11

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image captured by NASA 2001 Mars Odyssey spacecraft shows part of Coprates Chasma.

False Color Surface

NASA Image and Video Library

2014-12-26

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the region near Nili Fossae.

Craters - False Color

NASA Image and Video Library

2016-02-04

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image captured by NASA 2001 Mars Odyssey spacecraft shows a group of unnamed craters north of Fournier Crater.

Eos Chasma - False Color

NASA Image and Video Library

2014-12-16

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of of Eos Chasma.

Ascraeus Mons - False Color

NASA Image and Video Library

2015-01-06

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows the southern flank of Ascraeus Mons.

Syrtis Major - False Color

NASA Image and Video Library

2015-01-09

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows a region in Syrtis Major.

Capri Mensa - False Color

NASA Image and Video Library

2015-07-27

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows part of Capri Mensa and Capri Chasma.

Multiple-channel guided mode resonance Brewster filter with controllable spectral separation.

PubMed

Ma, Jianyong; Cao, Hongchao; Zhou, Changhe

2014-05-01

In this work, a single-layer, multiple-channel guided mode resonance (GMR) Brewster filter with controllable spectral separation is proposed using the plane waveguide method and rigorous coupled-wave analysis. Based on the normalized eigenvalue equation, the controllability of the spectral separation is analyzed when the fill ratio of the grating layer is changed while its effective index is identical to that of the substrate. The location and the separation between resonances can be specifically controlled by modifying the fill ratio of the grating layer. In contrast to the ordinary GMR filter, where the location of the resonances is material dependent, it is demonstrated that the spectral separation for the first and second resonances can be linearly controlled by altering the fill ratio of the grating layer. In addition, the maximal shift of the second resonance is up to 5% of the first resonant wavelength using the single-layer Brewster filter.

Comparative Gene Expression Profiles Induced by PPARγ and PPARα/γ Agonists in Human Hepatocytes

PubMed Central

Rogue, Alexandra; Lambert, Carine; Jossé, Rozenn; Antherieu, Sebastien; Spire, Catherine; Claude, Nancy; Guillouzo, André

2011-01-01

Background Several glitazones (PPARγ agonists) and glitazars (dual PPARα/γ agonists) have been developed to treat hyperglycemia and, simultaneously, hyperglycemia and dyslipidemia, respectively. However, most have caused idiosyncratic hepatic or extrahepatic toxicities through mechanisms that remain largely unknown. Since the liver plays a key role in lipid metabolism, we analyzed changes in gene expression profiles induced by these two types of PPAR agonists in human hepatocytes. Methodology/Principal Findings Primary human hepatocytes and the well-differentiated human hepatoma HepaRG cells were exposed to different concentrations of two PPARγ (troglitazone and rosiglitazone) and two PPARα/γ (muraglitazar and tesaglitazar) agonists for 24 h and their transcriptomes were analyzed using human pangenomic Agilent microarrays. Principal Component Analysis, hierarchical clustering and Ingenuity Pathway Analysis® revealed large inter-individual variability in the response of the human hepatocyte populations to the different compounds. Many genes involved in lipid, carbohydrate, xenobiotic and cholesterol metabolism, as well as inflammation and immunity, were regulated by both PPARγ and PPARα/γ agonists in at least a number of human hepatocyte populations and/or HepaRG cells. Only a few genes were selectively deregulated by glitazars when compared to glitazones, indicating that PPARγ and PPARα/γ agonists share most of their target genes. Moreover, some target genes thought to be regulated only in mouse or to be expressed in Kupffer cells were also found to be responsive in human hepatocytes and HepaRG cells. Conclusions/Significance This first comprehensive analysis of gene regulation by PPARγ and PPARα/γ agonists favor the conclusion that glitazones and glitazars share most of their target genes and induce large differential changes in gene profiles in human hepatocytes depending on hepatocyte donor, the compound class and/or individual compound, thereby supporting the occurrence of idiosyncratic toxicity in some patients. PMID:21533120

Prospective evaluation of FibroTest®, FibroMeter®, and HepaScore® for staging liver fibrosis in chronic hepatitis B: comparison with hepatitis C.

PubMed

Leroy, Vincent; Sturm, Nathalie; Faure, Patrice; Trocme, Candice; Marlu, Alice; Hilleret, Marie-Noëlle; Morel, Françoise; Zarski, Jean-Pierre

2014-07-01

Fibrosis blood tests have been validated in chronic hepatitis C. Their diagnostic accuracy is less documented in hepatitis B. The aim of this study was to describe the diagnostic performance of FibroTest®, FibroMeter®, and HepaScore® for liver fibrosis in hepatitis B compared to hepatitis C. 510 patients mono-infected with hepatitis B or C and matched on fibrosis stage were included. Blood tests were performed the day of the liver biopsy. Histological lesions were staged according to METAVIR. Fibrosis stages were distributed as followed: F0 n=76, F1 n=192, F2 n=132, F3 n=54, F4 n=56. Overall diagnostic performance of blood tests were similar between hepatitis B and C with AUROC ranging from 0.75 to 0.84 for significant fibrosis, 0.82 to 0.85 for extensive fibrosis and 0.84 to 0.87 for cirrhosis. Optimal cut-offs were consistently lower in hepatitis B compared to hepatitis C, especially for the diagnosis of extensive fibrosis and cirrhosis, with decreased sensitivity and negative predictive values. More hepatitis B than C patients with F ⩾3 were underestimated: FibroTest®: 47% vs. 26%, FibroMeter®: 24% vs. 6%, HepaScore®: 41% vs. 24%, p<0.01. Multivariate analysis showed that hepatitis B (0R 3.4, 95% CI 1.2-19.2, p<0.02) and low γGT (OR 7.3, 95% CI 2.0-27.0, p<0.003) were associated with fibrosis underestimation. Overall the diagnostic performance of blood tests is similar in hepatitis B and C. The risk of underestimating significant fibrosis and cirrhosis is however greater in hepatitis B and cannot be entirely corrected by the use of more stringent cut-offs. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Tailored liquid chromatography-mass spectrometry analysis improves the coverage of the intracellular metabolome of HepaRG cells.

PubMed

Cuykx, Matthias; Negreira, Noelia; Beirnaert, Charlie; Van den Eede, Nele; Rodrigues, Robim; Vanhaecke, Tamara; Laukens, Kris; Covaci, Adrian

2017-03-03

Metabolomics protocols are often combined with Liquid Chromatography-Mass Spectrometry (LC-MS) using mostly reversed phase chromatography coupled to accurate mass spectrometry, e.g. quadrupole time-of-flight (QTOF) mass spectrometers to measure as many metabolites as possible. In this study, we optimised the LC-MS separation of cell extracts after fractionation in polar and non-polar fractions. Both phases were analysed separately in a tailored approach in four different runs (two for the non-polar and two for the polar-fraction), each of them specifically adapted to improve the separation of the metabolites present in the extract. This approach improves the coverage of a broad range of the metabolome of the HepaRG cells and the separation of intra-class metabolites. The non-polar fraction was analysed using a C18-column with end-capping, mobile phase compositions were specifically adapted for each ionisation mode using different co-solvents and buffers. The polar extracts were analysed with a mixed mode Hydrophilic Interaction Liquid Chromatography (HILIC) system. Acidic metabolites from glycolysis and the Krebs cycle, together with phosphorylated compounds, were best detected with a method using ion pairing (IP) with tributylamine and separation on a phenyl-hexyl column. Accurate mass detection was performed with the QTOF in MS-mode only using an extended dynamic range to improve the quality of the dataset. Parameters with the greatest impact on the detection were the balance between mass accuracy and linear range, the fragmentor voltage, the capillary voltage, the nozzle voltage, and the nebuliser pressure. By using a tailored approach for the intracellular HepaRG metabolome, consisting of three different LC techniques, over 2200 metabolites can be measured with a high precision and acceptable linear range. The developed method is suited for qualitative untargeted LC-MS metabolomics studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Tracking Algorithm of Multiple Pedestrians Based on Particle Filters in Video Sequences

PubMed Central

Liu, Yun; Wang, Chuanxu; Zhang, Shujun; Cui, Xuehong

2016-01-01

Pedestrian tracking is a critical problem in the field of computer vision. Particle filters have been proven to be very useful in pedestrian tracking for nonlinear and non-Gaussian estimation problems. However, pedestrian tracking in complex environment is still facing many problems due to changes of pedestrian postures and scale, moving background, mutual occlusion, and presence of pedestrian. To surmount these difficulties, this paper presents tracking algorithm of multiple pedestrians based on particle filters in video sequences. The algorithm acquires confidence value of the object and the background through extracting a priori knowledge thus to achieve multipedestrian detection; it adopts color and texture features into particle filter to get better observation results and then automatically adjusts weight value of each feature according to current tracking environment. During the process of tracking, the algorithm processes severe occlusion condition to prevent drift and loss phenomena caused by object occlusion and associates detection results with particle state to propose discriminated method for object disappearance and emergence thus to achieve robust tracking of multiple pedestrians. Experimental verification and analysis in video sequences demonstrate that proposed algorithm improves the tracking performance and has better tracking results. PMID:27847514

A ROle-Oriented Filtering (ROOF) approach for collaborative recommendation

NASA Astrophysics Data System (ADS)

Ghani, Imran; Jeong, Seung Ryul

2016-09-01

In collaborative filtering (CF) recommender systems, existing techniques frequently focus on determining similarities among users' historical interests. This generally refers to situations in which each user normally plays a single role and his/her taste remains consistent over the long term. However, we note that existing techniques have not been significantly employed in a role-oriented context. This is especially so in situations where users may change their roles over time or play multiple roles simultaneously, while still expecting to access relevant information resources accordingly. Such systems include enterprise architecture management systems, e-commerce sites or journal management systems. In scenarios involving existing techniques, each user needs to build up very different profiles (preferences and interests) based on multiple roles which change over time. Should this not occur to a satisfactory degree, their previous information will either be lost or not utilised at all. To limit the occurrence of such issues, we propose a ROle-Oriented Filtering (ROOF) approach focusing on the manner in which multiple user profiles are obtained and maintained over time. We conducted a number of experiments using an enterprise architecture management scenario. In so doing, we observed that the ROOF approach performs better in comparison with other existing collaborative filtering-based techniques.

Tyrrhena Terra - False Color

NASA Image and Video Library

2014-12-12

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of an unnamed crater in Tyrrhena Terra.

Pollack Crater - False Color

NASA Image and Video Library

2015-01-16

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the floor of Pollack Crater.

Sulci Gordii - False Color

NASA Image and Video Library

2014-12-29

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Sulci Gordii east of Olympus Mons.

Pit Crater - False Color

NASA Image and Video Library

2015-06-18

The THEMIS VIS camera contains 5 filters. Data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows the central pit of an unnamed crater south of Coprates Catena.

Becquerel Crater - False Color

NASA Image and Video Library

2015-03-17

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the floor of Becquerel Crater.

Antoniadi Crater - False Color

NASA Image and Video Library

2014-12-22

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the floor of Antoniadi Crater.

Hecates Tholus - False Color

NASA Image and Video Library

2014-12-30

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the flank of Hecates Tholus.

Terra Sabaea - False Color

NASA Image and Video Library

2016-02-05

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows a variety of surface materials in the plains of Sabaea Terra.

Calahorra Crater - False Color

NASA Image and Video Library

2014-12-24

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Calahorra Crater in Chryse Planitia.

North Polar Cap - False Color

NASA Image and Video Library

2015-01-28

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows the margin of the north polar cap.

Gusev Crater - False Color

NASA Image and Video Library

2015-01-19

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows windstreaks on the floor of Gusev Crater.

Terra Cimmeria - False Color

NASA Image and Video Library

2015-07-15

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the plains of Terra Cimmeria.

Channel - False Color

NASA Image and Video Library

2015-05-25

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of an unnamed channel in Terra Cimmeria.

Wegener Crater Dunes - False Color

NASA Image and Video Library

2016-06-23

The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows some of the dunes on the floor of Wegener Crater.

Crater - False Color

NASA Image and Video Library

2015-05-26

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of an unnamed crater in Terra Cimmeria.

Daga Vallis - False Color

NASA Image and Video Library

2014-12-19

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Daga Vallis on Eos Mensa.

Proctor Crater - False Color

NASA Image and Video Library

2014-12-15

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the floor of Proctor Crater.

Ganges Chasma - False Color

NASA Image and Video Library

2015-01-27

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the interior of Ganges Chasma.

High-energy mode-locked fiber lasers using multiple transmission filters and a genetic algorithm.

PubMed

Fu, Xing; Kutz, J Nathan

2013-03-11

We theoretically demonstrate that in a laser cavity mode-locked by nonlinear polarization rotation (NPR) using sets of waveplates and passive polarizer, the energy performance can be significantly increased by incorporating multiple NPR filters. The NPR filters are engineered so as to mitigate the multi-pulsing instability in the laser cavity which is responsible for limiting the single pulse per round trip energy in a myriad of mode-locked cavities. Engineering of the NPR filters for performance is accomplished by implementing a genetic algorithm that is capable of systematically identifying viable and optimal NPR settings in a vast parameter space. Our study shows that five NPR filters can increase the cavity energy by approximately a factor of five, with additional NPRs contributing little or no enhancements beyond this. With the advent and demonstration of electronic controls for waveplates and polarizers, the analysis suggests a general design and engineering principle that can potentially close the order of magnitude energy gap between fiber based mode-locked lasers and their solid state counterparts.

Enhancement of Seebeck coefficient in graphene superlattices by electron filtering technique

NASA Astrophysics Data System (ADS)

Mishra, Shakti Kumar; Kumar, Amar; Kaushik, Chetan Prakash; Dikshit, Biswaranjan

2018-01-01

We show theoretically that the Seebeck coefficient and the thermoelectric figure of merit can be increased by using electron filtering technique in graphene superlattice based thermoelectric devices. The average Seebeck coefficient for graphene-based thermoelectric devices is proportional to the integral of the distribution of Seebeck coefficient versus energy of electrons. The low energy electrons in the distribution curve are found to reduce the average Seebeck coefficient as their contribution is negative. We show that, with electron energy filtering technique using multiple graphene superlattice heterostructures, the low energy electrons can be filtered out and the Seebeck coefficient can be increased. The multiple graphene superlattice heterostructures can be formed by graphene superlattices with different periodic electric potentials applied above the superlattice. The overall electronic band gap of the multiple heterostructures is dependent upon the individual band gap of the graphene superlattices and can be tuned by varying the periodic electric potentials. The overall electronic band gap of the multiple heterostructures has to be properly chosen such that, the low energy electrons which cause negative Seebeck distribution in single graphene superlattice thermoelectric devices fall within the overall band gap formed by the multiple heterostructures. Although the electrical conductance is decreased in this technique reducing the thermoelectric figure of merit, the overall figure of merit is increased due to huge increase in Seebeck coefficient and its square dependency upon the Seebeck coefficient. This is an easy technique to make graphene superlattice based thermoelectric devices more efficient and has the potential to significantly improve the technology of energy harvesting and sensors.

Attitude Error Representations for Kalman Filtering

NASA Technical Reports Server (NTRS)

Markley, F. Landis; Bauer, Frank H. (Technical Monitor)

2002-01-01

The quaternion has the lowest dimensionality possible for a globally nonsingular attitude representation. The quaternion must obey a unit norm constraint, though, which has led to the development of an extended Kalman filter using a quaternion for the global attitude estimate and a three-component representation for attitude errors. We consider various attitude error representations for this Multiplicative Extended Kalman Filter and its second-order extension.

Systolic Signal Processor/High Frequency Direction Finding

DTIC Science & Technology

1990-10-01

MUSIC ) algorithm and the finite impulse response (FIR) filter onto the testbed hardware was supported by joint sponsorship of the block and major bid...computational throughput. The systolic implementations of a four-channel finite impulse response (FIR) filter and multiple signal classification ( MUSIC ... MUSIC ) algorithm was mated to a bank of finite impulse response (FIR) filters and a four-channel data acquisition subsystem. A complete description

Military Vaccines in Today’s Environment

DTIC Science & Technology

2012-08-01

vaccines for anthrax, plague, influenza, rubella, ade- noviruses, meningococci, hepatitis B, typhoid , Japanese encephalitis, and hepa- titis A...licensed vaccines for naturally occurring diseases, such as those for yellow fever , mumps, measles, chickenpox and polio, were developed with the...HIV-AIDS, Chikungunya, Rift Valley fever , Argentinian hemorrhagic fever , and hemorrhagic fever with renal syndrome (HFRS), have been developed and

Evaluation of In Vitro Biotransformation Using HepaRG Cells to Improve High-Throughput Chemical Hazard Prediction: A Toxicogenomics Analysis (SOT)

EPA Science Inventory

The US EPA’s ToxCast program has generated a wealth of data in >600 in vitro assayson a library of 1060 environmentally relevant chemicals and failed pharmaceuticals to facilitate hazard identification. An inherent criticism of many in vitro-based strategies is the inability of a...

Making Healthy Eating and Physical Activity Policy Practice: Process Evaluation of a Group Randomized Controlled Intervention in Afterschool Programs

ERIC Educational Resources Information Center

Weaver, R. Glenn; Beets, Michael W.; Hutto, Brent; Saunders, Ruth P.; Moore, Justin B.; Turner-McGrievy, Gabrielle; Huberty, Jennifer L.; Ward, Dianne S.; Pate, Russell R.; Beighle, Aaron; Freedman, Darcy

2015-01-01

This study describes the link between level of implementation and outcomes from an intervention to increase afterschool programs' (ASPs) achievement of healthy eating and physical activity (HE-PA) Standards. Ten intervention ASPs implemented the Strategies-To-Enhance-Practice (STEPs), a multi-component, adaptive intervention framework identifying…

Identifying Strategies Programs Adopt to Meet Healthy Eating and Physical Activity Standards in Afterschool Programs

ERIC Educational Resources Information Center

Weaver, Robert G.; Moore, Justin B.; Turner-McGrievy, Brie; Saunders, Ruth; Beighle, Aaron; Khan, M. Mahmud; Chandler, Jessica; Brazendale, Keith; Randell, Allison; Webster, Collin; Beets, Michael W.

2017-01-01

Background: The YMCA of USA has adopted Healthy Eating and Physical Activity (HEPA) Standards for its afterschool programs (ASPs). Little is known about strategies YMCA ASPs are implementing to achieve Standards and these strategies' effectiveness. Aims: (1) Identify strategies implemented in YMCA ASPs and (2) evaluate the relationship between…

Multiwavelength absorbance of filter deposits for determination of environmental tobacco smoke and black carbon

NASA Astrophysics Data System (ADS)

Lawless, Phil A.; Rodes, Charles E.; Ensor, David S.

A multiwavelength optical absorption technique has been developed for Teflon filters used for personal exposure sampling with sufficient sensitivity to allow apportionments of environmental tobacco smoke and soot (black) carbon to be made. Measurements on blank filters show that the filter material itself contributes relatively little to the total absorbance and filters from the same lot have similar characteristics; this makes retrospective analysis of filters quite feasible. Using an integrating sphere radiometer and multiple wavelengths to provide specificity, the determination of tobacco smoke and carbon with reasonable accuracy is possible on filters not characterized before exposure. This technique provides a low cost, non-destructive exposure assessment alternative to both standard thermo-gravimetric elemental carbon evaluations on quartz filters and cotinine analyses from urine or saliva samples. The method allows the same sample filter to be used for assessment of mass, carbon, and tobacco smoke without affecting the deposit.

UV Filters and Toursim: Their Impact on the Environment

EPA Science Inventory

Ultraviolet (UV) filters are widely used in cosmetics, sunscreens, and plastics to block UV radiation from the sun. Studies show that some sunscreens demonstrate estrogenicity and multiple hormonal activities in vitro. Because of the high consumption volume and high lipophilicity...

Ares Vallis - False Color

NASA Image and Video Library

2015-09-18

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows the beginning of Ares Vallis at the edge of Iani Chaos.

Saheki Crater - False Color

NASA Image and Video Library

2015-06-26

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the rim and floor of Saheki Crater.

Peak-Seeking Control Using Gradient and Hessian Estimates

NASA Technical Reports Server (NTRS)

Ryan, John J.; Speyer, Jason L.

2010-01-01

A peak-seeking control method is presented which utilizes a linear time-varying Kalman filter. Performance function coordinate and magnitude measurements are used by the Kalman filter to estimate the gradient and Hessian of the performance function. The gradient and Hessian are used to command the system toward a local extremum. The method is naturally applied to multiple-input multiple-output systems. Applications of this technique to a single-input single-output example and a two-input one-output example are presented.

Error Measurements in an Acousto-Optic Tunable Filter Fiber Bragg Grating Sensor System

DTIC Science & Technology

1994-05-01

for an ideal AOTF, at 833 and 838 nm using a TeO2 crystal ............................ 33 Figure 3.12. Frequency characteristics of Equation (3.43...multiple channels in an AOTF requires the presence of multiple RF frequencies to establish the complex grating. Since the crystal used in the AOTF ( TeO2 ) is...in germano- silicate glass . This index modulation, Bragg grating, acts as an optical band rejection filter for those wavelengths that meet the Bragg

Robotic Vision, Tray-Picking System Design Using Multiple, Optical Matched Filters

NASA Astrophysics Data System (ADS)

Leib, Kenneth G.; Mendelsohn, Jay C.; Grieve, Philip G.

1986-10-01

The optical correlator is applied to a robotic vision, tray-picking problem. Complex matched filters (MFs) are designed to provide sufficient optical memory for accepting any orientation of the desired part, and a multiple holographic lens (MHL) is used to increase the memory for continuous coverage. It is shown that with appropriate thresholding a small part can be selected using optical matched filters. A number of criteria are presented for optimizing the vision system. Two of the part-filled trays that Mendelsohn used are considered in this paper which is the analog (optical) expansion of his paper. Our view in this paper is that of the optical correlator as a cueing device for subsequent, finer vision techniques.

A New Adaptive H-Infinity Filtering Algorithm for the GPS/INS Integrated Navigation

PubMed Central

Jiang, Chen; Zhang, Shu-Bi; Zhang, Qiu-Zhao

2016-01-01

The Kalman filter is an optimal estimator with numerous applications in technology, especially in systems with Gaussian distributed noise. Moreover, the adaptive Kalman filtering algorithms, based on the Kalman filter, can control the influence of dynamic model errors. In contrast to the adaptive Kalman filtering algorithms, the H-infinity filter is able to address the interference of the stochastic model by minimization of the worst-case estimation error. In this paper, a novel adaptive H-infinity filtering algorithm, which integrates the adaptive Kalman filter and the H-infinity filter in order to perform a comprehensive filtering algorithm, is presented. In the proposed algorithm, a robust estimation method is employed to control the influence of outliers. In order to verify the proposed algorithm, experiments with real data of the Global Positioning System (GPS) and Inertial Navigation System (INS) integrated navigation, were conducted. The experimental results have shown that the proposed algorithm has multiple advantages compared to the other filtering algorithms. PMID:27999361

A New Adaptive H-Infinity Filtering Algorithm for the GPS/INS Integrated Navigation.

PubMed

Jiang, Chen; Zhang, Shu-Bi; Zhang, Qiu-Zhao

2016-12-19

The Kalman filter is an optimal estimator with numerous applications in technology, especially in systems with Gaussian distributed noise. Moreover, the adaptive Kalman filtering algorithms, based on the Kalman filter, can control the influence of dynamic model errors. In contrast to the adaptive Kalman filtering algorithms, the H-infinity filter is able to address the interference of the stochastic model by minimization of the worst-case estimation error. In this paper, a novel adaptive H-infinity filtering algorithm, which integrates the adaptive Kalman filter and the H-infinity filter in order to perform a comprehensive filtering algorithm, is presented. In the proposed algorithm, a robust estimation method is employed to control the influence of outliers. In order to verify the proposed algorithm, experiments with real data of the Global Positioning System (GPS) and Inertial Navigation System (INS) integrated navigation, were conducted. The experimental results have shown that the proposed algorithm has multiple advantages compared to the other filtering algorithms.

Apparatus for measuring the decontamination factor of a multiple filter air-cleaning system

DOEpatents

Ortiz, John P.

1986-01-01

An apparatus for measuring the overall decontamination factor of first and second filters located in a plenum. The first filter separates the plenum's upstream and intermediate chambers. The second filter separates the plenum's intermediate and downstream chambers. The apparatus comprises an aerosol generator that generates a challenge aerosol. An upstream collector collects unfiltered aerosol which is piped to first and second dilution stages and then to a laser aerosol spectrometer. An intermediate collector collects challenge aerosol that penetrates the first filter. The filtered aerosol is piped to the first dilution stage, diluted, and then piped to the laser aerosol spectrometer which detects single particles. A downstream collector collects challenge aerosol that penetrates both filters. The twice-filtered aerosol is piped to the aerosol spectrometer. A pump and several valves control the movement of aerosol within the apparatus.