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Sample records for filter type respirators

  1. Penetration of asbestos fibers in respirator filters

    Cheng, Yung-Sung; Pearson, S.D.; Rohrbacher, K.D.; Yeh, Hsu-Chi.

    1994-01-01

    Currently, the health risks associated with asbestos have restricted its use and created a growing asbestos abatement industry with a need for respirator filters that are effective for worker protection. The main purpose of this project is to determine the influence of fiber size, electrostatic charge, and flow rate on the penetration of asbestos fibers in respirator filter cartridges. The study includes four types of filters each tested at two flow rates: the AO-R57A, a dual cartridge HEPA filter tested at 16 and 42.5 L/min; the MSA-S, a dust and mist filter tested at 16 and 42.5 L/min; the MSA-A power filter tested at 32 and 85 L/min; and the 3M-8710, a low-efficiency disposable face mask filter tested at 32 and 85 L/min. The three types of asbestos fibers used (amosite, crocidolite, and chrysotile) ranged in length from 0.04-0.5 μm and in aspect ratio (ratio of length to diameter) from 3 to 60. The fibers were used in both charged and neutralized forms. The results from amosite fibers are reported here

  2. Penetration of Combustion Aerosol Particles Through Filters of NIOSH-Certified Filtering Facepiece Respirators (FFRs).

    Gao, Shuang; Kim, Jinyong; Yermakov, Michael; Elmashae, Yousef; He, Xinjian; Reponen, Tiina; Grinshpun, Sergey A

    2015-01-01

    Filtering facepiece respirators (FFRs) are commonly worn by first responders, first receivers, and other exposed groups to protect against exposure to airborne particles, including those originated by combustion. Most of these FFRs are NIOSH-certified (e.g., N95-type) based on the performance testing of their filters against charge-equilibrated aerosol challenges, e.g., NaCl. However, it has not been examined if the filtration data obtained with the NaCl-challenged FFR filters adequately represent the protection against real aerosol hazards such as combustion particles. A filter sample of N95 FFR mounted on a specially designed holder was challenged with NaCl particles and three combustion aerosols generated in a test chamber by burning wood, paper, and plastic. The concentrations upstream (Cup) and downstream (Cdown) of the filter were measured with a TSI P-Trak condensation particle counter and a Grimm Nanocheck particle spectrometer. Penetration was determined as (Cdown/Cup) ×100%. Four test conditions were chosen to represent inhalation flows of 15, 30, 55, and 85 L/min. Results showed that the penetration values of combustion particles were significantly higher than those of the "model" NaCl particles (p combustion particles. Aerosol type, inhalation flow rate and particle size were significant (p combustion particles through R95 and P95 FFR filters (were tested in addition to N95) were not significantly higher than that obtained with NaCl particles. The findings were attributed to several effects, including the degradation of an N95 filter due to hydrophobic organic components generated into the air by combustion. Their interaction with fibers is anticipated to be similar to those involving "oily" particles. The findings of this study suggest that the efficiency of N95 respirator filters obtained with the NaCl aerosol challenge may not accurately predict (and rather overestimate) the filter efficiency against combustion particles.

  3. Independent Evaluation of The Lepestok Filtering Facepiece Respirator

    Hoover, Mark D; Vargo, George J

    2001-01-01

    The purpose of this study was to determine the protection factor of the Lepestok-200 filtering facepiece respirator by conducting a standard quantitative fit test on a panel of 25 representative adults (14 males and 11 females) using the TSI Incorporated PortaCount PlusTM quantitative fit-testing system. Each subject was tested four times. In the total of 100 tests, 95% of the overall fit factors were greater than 3, more than 80% of the overall fit factors were greater than 14, approximately 50% were greater than 86, and 20% were greater than 200. The pass-fail performance of the respirator was similar for each of the six exercises in the test series: (1) normal breathing, (2) deep breathing, (3) moving the head side to side, (4) moving the head up and down, (5) reading a passage of text out loud, and (6) normal breathing, indicating that the respirator performs equally well for each type of exercise. A significant and sustained improvement in fit factor was observed after the initial test, indicating that the subjects benefited from the knowledge gained in the first of the four quantitative fit tests. In the 75 tests conducted after the initial test for each individual, 95% of the overall fit factors were greater than 6, more than 80% of the overall fit factors were greater than 23, and 50% were greater than 116, and 20% were greater than 200. Thus, the initial learning experienced doubled the fit factor for subsequent tests. In addition, there is an indication that the Lepestok-200 may perform better on wearers with wider faces than on individuals with narrower faces. The results of this study demonstrate the effectiveness of the Lepestok-200 respirator and reinforce the general conclusion that quantitative fit-testing can make an important contribution to ensuring that proper protection factors are achieved for workers

  4. Disclosure and Fit Capability of the Filtering Facepiece Respirator.

    Lofgren, Don J

    2018-05-01

    The filtering facepiece air-purifying respirator is annually purchased in the tens of millions and widely used for worker protection from harmful airborne particulates. The workplace consumers of this safety product, i.e., employers, workers, and safety and health professionals, have assurances of its effectiveness through the respirator certification and disclosure requirements of the National Institute for Occupational Safety and Health. However, the certification of a critical performance requirement has been missing for the approved filtering facepiece respirator since 1995: fit capability. Without this certification, consumers continue to be at risk of purchasing a respirator model that may fit a small percentage of the intended users. This commentary updates and expands an earlier one by this author, addresses the consequences of poorly fitting certified models on the market and lack of disclosure, and calls for further action by National Institute for Occupational Safety and Health to meet the needs and expectations of the consumer.

  5. Gravimetric Measurements of Filtering Facepiece Respirators Challenged With Diesel Exhaust.

    Satish, Swathi; Swanson, Jacob J; Xiao, Kai; Viner, Andrew S; Kittelson, David B; Pui, David Y H

    2017-07-01

    Elevated concentrations of diesel exhaust have been linked to adverse health effects. Filtering facepiece respirators (FFRs) are widely used as a form of respiratory protection against diesel particulate matter (DPM) in occupational settings. Previous results (Penconek A, Drążyk P, Moskal A. (2013) Penetration of diesel exhaust particles through commercially available dust half masks. Ann Occup Hyg; 57: 360-73.) have suggested that common FFRs are less efficient than would be expected for this purpose based on their certification approvals. The objective of this study was to measure the penetration of DPM through NIOSH-certified R95 and P95 electret respirators to verify this result. Gravimetric-based penetration measurements conducted using polytetrafluoroethylene (PTFE) and polypropylene (PP) filters were compared with penetration measurements made with a Scanning Mobility Particle Sizer (SMPS, TSI Inc.), which measures the particle size distribution. Gravimetric measurements using PP filters were variable compared to SMPS measurements and biased high due to adsorption of gas phase organic material. Relatively inert PTFE filters adsorbed less gas phase organic material resulting in measurements that were more accurate. To attempt to correct for artifacts associated with adsorption of gas phase organic material, primary and secondary filters were used in series upstream and downstream of the FFR. Correcting for adsorption by subtracting the secondary mass from the primary mass improved the result for both PTFE and PP filters but this correction is subject to 'equilibrium' conditions that depend on sampling time and the concentration of particles and gas phase hydrocarbons. Overall, the results demonstrate that the use of filters to determine filtration efficiency of FFRs challenged with diesel exhaust produces erroneous results due to the presence of gas phase hydrocarbons in diesel exhaust and the tendency of filters to adsorb organic material. Published by

  6. 42 CFR 84.1151 - DOP filter test; respirators designed as respiratory protection against dusts, fumes, and mists...

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false DOP filter test; respirators designed as... filter test; respirators designed as respiratory protection against dusts, fumes, and mists having an air...) All single air-purifying respirator filter units will be tested in an atmosphere concentration of 100...

  7. Efficiency of Respirator Filter Media against Diesel Particulate Matter: A Comparison Study Using Two Diesel Particulate Sources.

    Burton, Kerrie A; Whitelaw, Jane L; Jones, Alison L; Davies, Brian

    2016-07-01

    Diesel engines have been a mainstay within many industries since the early 1900s. Exposure to diesel particulate matter (DPM) is a major issue in many industrial workplaces given the potential for serious health impacts to exposed workers; including the potential for lung cancer and adverse irritant and cardiovascular effects. Personal respiratory protective devices are an accepted safety measure to mitigate worker exposure against the potentially damaging health impacts of DPM. To be protective, they need to act as effective filters against carbon and other particulates. In Australia, the filtering efficiency of respiratory protective devices is determined by challenging test filter media with aerosolised sodium chloride to determine penetration at designated flow rates. The methodology outlined in AS/NZS1716 (Standards Australia International Ltd and Standards New Zealand 2012. Respiratory protective devices. Sydney/Wellington: SAI Global Limited/Standards New Zealand) does not account for the differences between characteristics of workplace contaminants like DPM and sodium chloride such as structure, composition, and particle size. This study examined filtering efficiency for three commonly used AS/NZS certified respirator filter models, challenging them with two types of diesel emissions; those from a diesel generator and a diesel engine. Penetration through the filter media of elemental carbon (EC), total carbon (TC), and total suspended particulate (TSP) was calculated. Results indicate that filtering efficiency assumed by P2 certification in Australia was achieved for two of the three respirator models for DPM generated using the small diesel generator, whilst when the larger diesel engine was used, filtering efficiency requirements were met for all three filter models. These results suggest that the testing methodology specified for certification of personal respiratory protective devices by Standards Australia may not ensure adequate protection for

  8. Nanoparticle filtration performance of NIOSH-certified particulate air-purifying filtering facepiece respirators: evaluation by light scattering photometric and particle number-based test methods.

    Rengasamy, Samy; Eimer, Benjamin C

    2012-01-01

    National Institute for Occupational Safety and Health (NIOSH) certification test methods employ charge neutralized NaCl or dioctyl phthalate (DOP) aerosols to measure filter penetration levels of air-purifying particulate respirators photometrically using a TSI 8130 automated filter tester at 85 L/min. A previous study in our laboratory found that widely different filter penetration levels were measured for nanoparticles depending on whether a particle number (count)-based detector or a photometric detector was used. The purpose of this study was to better understand the influence of key test parameters, including filter media type, challenge aerosol size range, and detector system. Initial penetration levels for 17 models of NIOSH-approved N-, R-, and P-series filtering facepiece respirators were measured using the TSI 8130 photometric method and compared with the particle number-based penetration (obtained using two ultrafine condensation particle counters) for the same challenge aerosols generated by the TSI 8130. In general, the penetration obtained by the photometric method was less than the penetration obtained with the number-based method. Filter penetration was also measured for ambient room aerosols. Penetration measured by the TSI 8130 photometric method was lower than the number-based ambient aerosol penetration values. Number-based monodisperse NaCl aerosol penetration measurements showed that the most penetrating particle size was in the 50 nm range for all respirator models tested, with the exception of one model at ~200 nm size. Respirator models containing electrostatic filter media also showed lower penetration values with the TSI 8130 photometric method than the number-based penetration obtained for the most penetrating monodisperse particles. Results suggest that to provide a more challenging respirator filter test method than what is currently used for respirators containing electrostatic media, the test method should utilize a sufficient number

  9. Transfer of bacteriophage MS2 and fluorescein from N95 filtering facepiece respirators to hands: Measuring fomite potential

    Brady, Tyler M.; Strauch, Amanda L.; Almaguer, Claudia M.; Niezgoda, George; Shafer, Ronald E.; Yorio, Patrick L.; Fisher, Edward M.

    2017-01-01

    Contact transmission of pathogens from personal protective equipment is a concern within the healthcare industry. During public health emergency outbreaks, resources become constrained and the reuse of personal protective equipment, such as N95 filtering facepiece respirators, may be needed. This study was designed to characterize the transfer of bacteriophage MS2 and fluorescein between filtering facepiece respirators and the wearer’s hands during three simulated use scenarios. Filtering facepiece respirators were contaminated with MS2 and fluorescein in droplets or droplet nuclei. Thirteen test subjects performed filtering facepiece respirator use scenarios including improper doffing, proper doffing and reuse, and improper doffing and reuse. Fluorescein and MS2 contamination transfer were quantified. The average MS2 transfer from filtering facepiece respirators to the subjects’ hands ranged from 7.6–15.4% and 2.2–2.7% for droplet and droplet nuclei derived contamination, respectively. Handling filtering facepiece respirators contaminated with droplets resulted in higher levels of MS2 transfer compared to droplet nuclei for all use scenarios (p = 0.007). MS2 transfer from droplet contaminated filtering facepiece respirators during improper doffing and reuse was greater than transfer during improper doffing (p = 0.008) and proper doffing and reuse (p = 0.042). Droplet contamination resulted in higher levels of fluorescein transfer compared to droplet nuclei contaminated filtering facepiece respirators for all use scenarios (p = 0.009). Fluorescein transfer was greater for improper doffing and reuse (p = 0.007) from droplet contaminated masks compared to droplet nuclei contaminated filtering facepiece respirators and for improper doffing and reuse when compared improper doffing (p = 0.017) and proper doffing and reuse (p = 0.018) for droplet contaminated filtering facepiece respirators. For droplet nuclei contaminated filtering facepiece respirators, the

  10. Size-Resolved Penetration of Filtering Materials from CE-Marked Filtering Facepiece Respirators.

    Serfozo, N.; Ondráček, Jakub; Zíková, Naděžda; Lazaridis, M.; Ždímal, Vladimír

    2017-01-01

    Roč. 17, č. 5 (2017), s. 1305-1315 ISSN 1680-8584 EU Projects: European Commission(XE) 315760 - HEXACOMM Institutional support: RVO:67985858 Keywords : size-resolved penetration * CE-marked respirator * monodisperse ammonium sulfate Subject RIV: DI - Air Pollution ; Quality OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 2.606, year: 2016

  11. Pressure drop of filtering facepiece respirators: How low should we go?

    Jung-Hyun Kim

    2015-02-01

    Full Text Available Introduction This study was undertaken to determine the mean peak filter resistance to airflow (Rfilter encountered by subjects while wearing prototype filtering facepiece respirators (PRs with low Rfilter during nasal and oral breathing at sedentary and low-moderate work rates. Material and methods In-line pressure transducer measurements of mean Rfilteracross PRs with nominal Rfilter of 29.4 Pa, 58.8 Pa and 88.2 Pa (measured at 85 l/min constant airflow were obtained during nasal and oral breathing at sedentary and low-moderate work rates for 10 subjects. Results The mean Rfilter for the 29.4 PR was significantly lower than the other 2 PRs (p 0.05. The mean Rfilter was greater for oral versus nasal breathing and for exercise compared to sedentary activity (p < 0.001. Conclusions Mean oral and nasal Rfilter for all 3 PRs was at, or below, the minimal threshold level for detection of inspiratory resistance (the 58.8–74.5 Pa/l×s–1, which may account for the previously-reported lack of significant subjective or physiological differences when wearing PRs with these low Rfilter. Lowering filtering facepiece respirator Rfilter below 88.2 Pa (measured at 85 l/min constant airflow may not result in additional subjective or physiological benefit to the wearer.

  12. Filter penetration and breathing resistance evaluation of respirators and dust masks.

    Ramirez, Joel; O'Shaughnessy, Patrick

    2017-02-01

    The primary objective of this study was to compare the filter performance of a representative selection of uncertified dust masks relative to the filter performance of a set of NIOSH-approved N95 filtering face-piece respirators (FFRs). Five different models of commercially available dust masks were selected for this study. Filter penetration of new dust masks was evaluated against a sodium chloride aerosol. Breathing resistance (BR) of new dust masks and FFRs was then measured for 120 min while challenging the dust masks and FFRs with Arizona road dust (ARD) at 25°C and 30% relative humidity. Results demonstrated that a wide range of maximum filter penetration was observed among the dust masks tested in this study (3-75% at the most penetrating particle size (p masks did not vary greatly (8-13 mm H 2 O) but were significantly different (p mask. Microscopic analysis of the external layer of each dust mask and FFR suggests that different collection media in the external layer influences the development of the dust layer and therefore affects the increase in BR differently between the tested models. Two of the dust masks had penetration values masks, those with penetration > 15%, had quality factors ranging between 0.04-0.15 primarily because their initial BR remained relatively high. These results indicate that some dust masks analysed during this research did not have an expected very low BR to compensate for their high penetration.

  13. Characterization of small-to-medium head-and-face dimensions for developing respirator fit test panels and evaluating fit of filtering facepiece respirators with different faceseal design

    Lin, Yi-Chun

    2017-01-01

    A respirator fit test panel (RFTP) with facial size distribution representative of intended users is essential to the evaluation of respirator fit for new models of respirators. In this study an anthropometric survey was conducted among youths representing respirator users in mid-Taiwan to characterize head-and-face dimensions key to RFTPs for application to small-to-medium facial features. The participants were fit-tested for three N95 masks of different facepiece design and the results compared to facial size distribution specified in the RFTPs of bivariate and principal component analysis design developed in this study to realize the influence of facial characteristics to respirator fit in relation to facepiece design. Nineteen dimensions were measured for 206 participants. In fit testing the qualitative fit test (QLFT) procedures prescribed by the U.S. Occupational Safety and Health Administration were adopted. As the results show, the bizygomatic breadth of the male and female participants were 90.1 and 90.8% of their counterparts reported for the U.S. youths (P < 0.001), respectively. Compared to the bivariate distribution, the PCA design better accommodated variation in facial contours among different respirator user groups or populations, with the RFTPs reported in this study and from literature consistently covering over 92% of the participants. Overall, the facial fit of filtering facepieces increased with increasing facial dimensions. The total percentages of the tests wherein the final maneuver being completed was “Moving head up-and-down”, “Talking” or “Bending over” in bivariate and PCA RFTPs were 13.3–61.9% and 22.9–52.8%, respectively. The respirators with a three-panel flat fold structured in the facepiece provided greater fit, particularly when the users moved heads. When the facial size distribution in a bivariate RFTP did not sufficiently represent petite facial size, the fit testing was inclined to overestimate the general fit

  14. Effect of Hyperglycemia on Mitochondrial Respiration in Type 2 Diabetes

    Rabøl, Rasmus; Højberg, Patricia M V; Almdal, Thomas

    2009-01-01

    AIM: Skeletal muscle mitochondrial content is reduced in type 2 diabetes mellitus (T2DM). Whether hyperglycemia inhibits mitochondrial biogenesis and/or function is unknown. This study examined the effect of different levels of glycemia on skeletal muscle mitochondrial function in patients with T2......DM. PATIENTS AND METHODS: Eleven patients with T2DM [9 males, 2 females; age, 52.8 +/- 2.5 yr (mean +/- se); body mass index, 30.2 +/- 1.1 kg/m(2)] in poor glycemic control were treated with insulin aspart and NPH insulin for a median period of 46 d (range, 31-59). Mitochondrial respiration...... and citrate synthase activity (a marker of mitochondrial content) were measured before and after treatment. Eleven healthy subjects (age, 53.3 +/- 2.7 yr; body mass index, 30.6 +/- 1.1 kg/m(2)) were included as controls. RESULTS: Hemoglobin A1c (9.1 +/- 0.5 to 7.5 +/- 0.3%; P

  15. Evaluation of the user seal check on gross leakage detection of 3 different designs of N95 filtering facepiece respirators.

    Lam, Simon C; Lui, Andrew K F; Lee, Linda Y K; Lee, Joseph K L; Wong, K F; Lee, Cathy N Y

    2016-05-01

    The use of N95 respirators prevents spread of respiratory infectious agents, but leakage hampers its protection. Manufacturers recommend a user seal check to identify on-site gross leakage. However, no empirical evidence is provided. Therefore, this study aims to examine validity of a user seal check on gross leakage detection in commonly used types of N95 respirators. A convenience sample of 638 nursing students was recruited. On the wearing of 3 different designs of N95 respirators, namely 3M-1860s, 3M-1862, and Kimberly-Clark 46827, the standardized user seal check procedure was carried out to identify gross leakage. Repeated testing of leakage was followed by the use of a quantitative fit testing (QNFT) device in performing normal breathing and deep breathing exercises. Sensitivity, specificity, predictive values, and likelihood ratios were calculated accordingly. As indicated by QNFT, prevalence of actual gross leakage was 31.0%-39.2% with the 3M respirators and 65.4%-65.8% with the Kimberly-Clark respirator. Sensitivity and specificity of the user seal check for identifying actual gross leakage were approximately 27.7% and 75.5% for 3M-1860s, 22.1% and 80.5% for 3M-1862, and 26.9% and 80.2% for Kimberly-Clark 46827, respectively. Likelihood ratios were close to 1 (range, 0.89-1.51) for all types of respirators. The results did not support user seal checks in detecting any actual gross leakage in the donning of N95 respirators. However, such a check might alert health care workers that donning a tight-fitting respirator should be performed carefully. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  16. Evaluation of Microwave Steam Bags for the Decontamination of Filtering Facepiece Respirators

    Fisher, Edward M.; Williams, Jessica L.; Shaffer, Ronald E.

    2011-01-01

    Reusing filtering facepiece respirators (FFRs) has been suggested as a strategy to conserve available supplies for home and healthcare environments during an influenza pandemic. For reuse to be possible, used FFRs must be decontaminated before redonning to reduce the risk of virus transmission; however, there are no approved methods for FFR decontamination. An effective method must reduce the microbial threat, maintain the function of the FFR, and present no residual chemical hazard. The method should be readily available, inexpensive and easily implemented by healthcare workers and the general public. Many of the general decontamination protocols used in healthcare and home settings are unable to address all of the desired qualities of an efficient FFR decontamination protocol. The goal of this study is to evaluate the use of two commercially available steam bags, marketed to the public for disinfecting infant feeding equipment, for FFR decontamination. The FFRs were decontaminated with microwave generated steam following the manufacturers' instructions then evaluated for water absorption and filtration efficiency for up to three steam exposures. Water absorption of the FFR was found to be model specific as FFRs constructed with hydrophilic materials absorbed more water. The steam had little effect on FFR performance as filtration efficiency of the treated FFRs remained above 95%. The decontamination efficacy of the steam bag was assessed using bacteriophage MS2 as a surrogate for a pathogenic virus. The tested steam bags were found to be 99.9% effective for inactivating MS2 on FFRs; however, more research is required to determine the effectiveness against respiratory pathogens. PMID:21525995

  17. Evaluation of microwave steam bags for the decontamination of filtering facepiece respirators.

    Edward M Fisher

    Full Text Available Reusing filtering facepiece respirators (FFRs has been suggested as a strategy to conserve available supplies for home and healthcare environments during an influenza pandemic. For reuse to be possible, used FFRs must be decontaminated before redonning to reduce the risk of virus transmission; however, there are no approved methods for FFR decontamination. An effective method must reduce the microbial threat, maintain the function of the FFR, and present no residual chemical hazard. The method should be readily available, inexpensive and easily implemented by healthcare workers and the general public. Many of the general decontamination protocols used in healthcare and home settings are unable to address all of the desired qualities of an efficient FFR decontamination protocol. The goal of this study is to evaluate the use of two commercially available steam bags, marketed to the public for disinfecting infant feeding equipment, for FFR decontamination. The FFRs were decontaminated with microwave generated steam following the manufacturers' instructions then evaluated for water absorption and filtration efficiency for up to three steam exposures. Water absorption of the FFR was found to be model specific as FFRs constructed with hydrophilic materials absorbed more water. The steam had little effect on FFR performance as filtration efficiency of the treated FFRs remained above 95%. The decontamination efficacy of the steam bag was assessed using bacteriophage MS2 as a surrogate for a pathogenic virus. The tested steam bags were found to be 99.9% effective for inactivating MS2 on FFRs; however, more research is required to determine the effectiveness against respiratory pathogens.

  18. Sensory pollution from bag-type fiberglass ventilation filters: Conventional filter compared with filters containing various amounts of activated carbon

    Bekö, Gabriel; Fadeyi, M.O.; Clausen, Geo

    2009-01-01

    filter and three modifications of a bag-type fiberglass combination filter: the "Heavy" corresponded to a commercially available filter containing 400 g of carbon per square meter of filter area, the "Medium" contained half as much carbon (200 g/m(2)), and the "Light" contained a quarter as much carbon...

  19. Effects of regionally applied heating on the respiration of wild type ...

    Nocturnal dark respiration (Rn) in wild type and transgenic soybean plants ... Illinois, USA under ambient and elevated CO2 conditions was examined in this study. ... Experimental plants were transferred to a controlled growth chamber at V4 ...

  20. 42 CFR 84.149 - Type C supplied-air respirator, demand and pressure demand class; minimum requirements.

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Type C supplied-air respirator, demand and pressure demand class; minimum requirements. 84.149 Section 84.149 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT... OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.149 Type C supplied-air respirator...

  1. Comfort and exertion while using filtering facepiece respirators with exhalation valve and an active venting system among male military personnel.

    Seng, Melvin; Wee, Liang En; Zhao, Xiahong; Cook, Alex R; Chia, Sin Eng; Lee, Vernon J

    2017-07-06

    This study aimed to determine if disposable filtering facepiece respirators (FFRs), with exhalation valve (EV) and a novel active venting system (AVS), provided greater perceived comfort and exertion when compared to standard N95 FFRs without these features among male military personnel performing prolonged essential outdoor duties. We used a randomised open-label controlled crossover study design to compare three FFR options: (a) standard FFR; (b) FFR with EV; and (c) FFR with EV+AVS. Male military personnel aged between 18 and 20 years completed a questionnaire at the beginning (baseline), after two hours of standardised non-strenuous outdoor duty and after 12 hours of duty divided into two-hour work-rest cycles. Participants rated the degree of discomfort, exertion and symptoms using a five-point Likert scale. The association between outcomes and the types of FFR was assessed using a multivariate ordered probit mixed-effects model. For a majority of the symptoms, study participants rated FFR with EV and FFR with EV+AVS with significantly better scores than standard FFR. Both FFR with EV and FFR with EV+AVS had significantly less discomfort (FFR with EV+AVS: 91.1%; FFR with EV: 57.6%) and exertion (FFR with EV+AVS: 83.5%; FFR with EV: 34.4%) than standard FFR. FFR with EV+AVS also had significantly better scores for exertion (53.4%) and comfort (39.4%) when compared to FFR with EV. Usage of FFR with EV+AVS resulted in significantly reduced symptoms, discomfort and exertion when compared to FFR with EV and standard FFR.

  2. Impact of environmental factors and biological soil crust types on soil respiration in a desert ecosystem.

    Feng, Wei; Zhang, Yuqing; Jia, Xin; Wu, Bin; Zha, Tianshan; Qin, Shugao; Wang, Ben; Shao, Chenxi; Liu, Jiabin; Fa, Keyu

    2014-01-01

    The responses of soil respiration to environmental conditions have been studied extensively in various ecosystems. However, little is known about the impacts of temperature and moisture on soils respiration under biological soil crusts. In this study, CO2 efflux from biologically-crusted soils was measured continuously with an automated chamber system in Ningxia, northwest China, from June to October 2012. The highest soil respiration was observed in lichen-crusted soil (0.93 ± 0.43 µmol m-2 s-1) and the lowest values in algae-crusted soil (0.73 ± 0.31 µmol m-2 s-1). Over the diurnal scale, soil respiration was highest in the morning whereas soil temperature was highest in the midday, which resulted in diurnal hysteresis between the two variables. In addition, the lag time between soil respiration and soil temperature was negatively correlated with the soil volumetric water content and was reduced as soil water content increased. Over the seasonal scale, daily mean nighttime soil respiration was positively correlated with soil temperature when moisture exceeded 0.075 and 0.085 m3 m-3 in lichen- and moss-crusted soil, respectively. However, moisture did not affect on soil respiration in algae-crusted soil during the study period. Daily mean nighttime soil respiration normalized by soil temperature increased with water content in lichen- and moss-crusted soil. Our results indicated that different types of biological soil crusts could affect response of soil respiration to environmental factors. There is a need to consider the spatial distribution of different types of biological soil crusts and their relative contributions to the total C budgets at the ecosystem or landscape level.

  3. Impact of Environmental Factors and Biological Soil Crust Types on Soil Respiration in a Desert Ecosystem

    Feng, Wei; Zhang, Yuqing; Jia, Xin; Wu, Bin; Zha, Tianshan; Qin, Shugao; Wang, Ben; Shao, Chenxi; Liu, Jiabin; Fa, Keyu

    2014-01-01

    The responses of soil respiration to environmental conditions have been studied extensively in various ecosystems. However, little is known about the impacts of temperature and moisture on soils respiration under biological soil crusts. In this study, CO2 efflux from biologically-crusted soils was measured continuously with an automated chamber system in Ningxia, northwest China, from June to October 2012. The highest soil respiration was observed in lichen-crusted soil (0.93±0.43 µmol m−2 s−1) and the lowest values in algae-crusted soil (0.73±0.31 µmol m−2 s−1). Over the diurnal scale, soil respiration was highest in the morning whereas soil temperature was highest in the midday, which resulted in diurnal hysteresis between the two variables. In addition, the lag time between soil respiration and soil temperature was negatively correlated with the soil volumetric water content and was reduced as soil water content increased. Over the seasonal scale, daily mean nighttime soil respiration was positively correlated with soil temperature when moisture exceeded 0.075 and 0.085 m3 m−3 in lichen- and moss-crusted soil, respectively. However, moisture did not affect on soil respiration in algae-crusted soil during the study period. Daily mean nighttime soil respiration normalized by soil temperature increased with water content in lichen- and moss-crusted soil. Our results indicated that different types of biological soil crusts could affect response of soil respiration to environmental factors. There is a need to consider the spatial distribution of different types of biological soil crusts and their relative contributions to the total C budgets at the ecosystem or landscape level. PMID:25050837

  4. Convergence in the temperature response of leaf respiration across biomes and plant functional types.

    Heskel, Mary A; O'Sullivan, Odhran S; Reich, Peter B; Tjoelker, Mark G; Weerasinghe, Lasantha K; Penillard, Aurore; Egerton, John J G; Creek, Danielle; Bloomfield, Keith J; Xiang, Jen; Sinca, Felipe; Stangl, Zsofia R; Martinez-de la Torre, Alberto; Griffin, Kevin L; Huntingford, Chris; Hurry, Vaughan; Meir, Patrick; Turnbull, Matthew H; Atkin, Owen K

    2016-04-05

    Plant respiration constitutes a massive carbon flux to the atmosphere, and a major control on the evolution of the global carbon cycle. It therefore has the potential to modulate levels of climate change due to the human burning of fossil fuels. Neither current physiological nor terrestrial biosphere models adequately describe its short-term temperature response, and even minor differences in the shape of the response curve can significantly impact estimates of ecosystem carbon release and/or storage. Given this, it is critical to establish whether there are predictable patterns in the shape of the respiration-temperature response curve, and thus in the intrinsic temperature sensitivity of respiration across the globe. Analyzing measurements in a comprehensive database for 231 species spanning 7 biomes, we demonstrate that temperature-dependent increases in leaf respiration do not follow a commonly used exponential function. Instead, we find a decelerating function as leaves warm, reflecting a declining sensitivity to higher temperatures that is remarkably uniform across all biomes and plant functional types. Such convergence in the temperature sensitivity of leaf respiration suggests that there are universally applicable controls on the temperature response of plant energy metabolism, such that a single new function can predict the temperature dependence of leaf respiration for global vegetation. This simple function enables straightforward description of plant respiration in the land-surface components of coupled earth system models. Our cross-biome analyses shows significant implications for such fluxes in cold climates, generally projecting lower values compared with previous estimates.

  5. Biophysical controls on soil respiration in the dominant patch types of an old-growth, mixed-conifer forest

    Siyan Ma; Jiquan Chen; John R. Butnor; Malcolm North; Eugénie S. Euskirchen; Brian Oakley

    2005-01-01

    Little is known about biophysical controls on soil respiration in California's Sierra Nevada old-growth, mixed-conifer forests. Using portable and automated soil respiration sampling units, we measured soil respiration rate (SRR) in three dominant patch types: closed canopy (CC), ceanothus-dominated patches (CECO), and open canopy (OC). SRR varied significantly...

  6. Manikin-Based Size-Resolved Penetrations of CE-marked Filtering Facepiece Respirators.

    Serfozo, N.; Ondráček, Jakub; Otáhal, P.; Lazaridis, M.; Ždímal, Vladimír

    2017-01-01

    Roč. 14, č. 12 (2017), s. 965-974 ISSN 1545-9624 EU Projects: European Commission(XE) 315760 - HEXACOMM Institutional support: RVO:67985858 Keywords : size-resolved penetration * manikin-based study * CE-marked respirator Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 1.200, year: 2016

  7. Evaluation of the filtration performance of NIOSH-approved N95 filtering facepiece respirators by photometric and number-based test methods.

    Rengasamy, Samy; Miller, Adam; Eimer, Benjamin C

    2011-01-01

    N95 particulate filtering facepiece respirators are certified by measuring penetration levels photometrically with a presumed severe case test method using charge neutralized NaCl aerosols at 85 L/min. However, penetration values obtained by photometric methods have not been compared with count-based methods using contemporary respirators composed of electrostatic filter media and challenged with both generated and ambient aerosols. To better understand the effects of key test parameters (e.g., particle charge, detection method), initial penetration levels for five N95 model filtering facepiece respirators were measured using NaCl aerosols with the aerosol challenge and test equipment employed in the NIOSH respirator certification method (photometric) and compared with an ultrafine condensation particle counter method (count based) for the same NaCl aerosols as well as for ambient room air particles. Penetrations using the NIOSH test method were several-fold less than the penetrations obtained by the ultrafine condensation particle counter for NaCl aerosols as well as for room particles indicating that penetration measurement based on particle counting offers a more difficult challenge than the photometric method, which lacks sensitivity for particles photometric method may not be a more challenging aerosol test method. Filter penetrations can vary among workplaces with different particle size distributions, which suggests the need for the development of new or revised "more challenging" aerosol test methods for NIOSH certification of respirators.

  8. Mitochondrial respiration is decreased in skeletal muscle of patients with type 2 diabetes

    Hey-Mogensen, Martin; Sahlin, Kent; Fernström, Maria

    2007-01-01

    , and the proportion of type 2X fibers correlated with markers of insulin resistance (P type 2X fibers in muscle of type 2 diabetic patients. These alterations may contribute to the development......We tested the hypothesis of a lower respiratory capacity per mitochondrion in skeletal muscle of type 2 diabetic patients compared with obese subjects. Muscle biopsies obtained from 10 obese type 2 diabetic and 8 obese nondiabetic male subjects were used for assessment of 3-hydroxy....... Maximal ADP-stimulated respiration (state 3) with pyruvate plus malate and respiration through the electron transport chain (ETC) were reduced in type 2 diabetic patients, and the proportion of type 2X fibers were higher in type 2 diabetic patients compared with obese subjects (all P

  9. Evidence-Based Evaluation of Inferior Vena Cava Filter Complications Based on Filter Type

    Deso, Steven E.; Idakoji, Ibrahim A.; Kuo, William T.

    2016-01-01

    Many inferior vena cava (IVC) filter types, along with their specific risks and complications, are not recognized. The purpose of this study was to evaluate the various FDA-approved IVC filter types to determine device-specific risks, as a way to help identify patients who may benefit from ongoing follow-up versus prompt filter retrieval. An evidence-based electronic search (FDA Premarket Notification, MEDLINE, FDA MAUDE) was performed to identify all IVC filter types and device-specific complications from 1980 to 2014. Twenty-three IVC filter types (14 retrievable, 9 permanent) were identified. The devices were categorized as follows: conical (n = 14), conical with umbrella (n = 1), conical with cylindrical element (n = 2), biconical with cylindrical element (n = 2), helical (n = 1), spiral (n = 1), and complex (n = 1). Purely conical filters were associated with the highest reported risks of penetration (90–100%). Filters with cylindrical or umbrella elements were associated with the highest reported risk of IVC thrombosis (30–50%). Conical Bard filters were associated with the highest reported risks of fracture (40%). The various FDA-approved IVC filter types were evaluated for device-specific complications based on best current evidence. This information can be used to guide and optimize clinical management in patients with indwelling IVC filters. PMID:27247477

  10. Rethinking anaerobic As(III) oxidation in filters: Effect of indigenous nitrate respirers.

    Cui, Jinli; Du, Jingjing; Tian, Haixia; Chan, Tingshan; Jing, Chuanyong

    2018-04-01

    Microorganisms play a key role in the redox transformation of arsenic (As) in aquifers. In this study, the impact of indigenous bacteria, especially the prevailing nitrate respirers, on arsenite (As(III)) oxidation was explored during groundwater filtration using granular TiO 2 and subsequent spent TiO 2 anaerobic landfill. X-ray absorption near edge structure spectroscopy analysis showed As(III) oxidation (46% in 10 days) in the presence of nitrate in the simulated anaerobic landfills. Meanwhile, iron (Fe) species on the spent TiO 2 were dominated by amorphous ferric arsenate, ferrihydrite and goethite. The Fe phase showed no change during the anaerobic landfill incubation. Batch incubation experiments implied that the indigenous bacteria completely oxidized As(III) to arsenate (As(V)) in 10 days using nitrate as the terminal electron acceptor under anaerobic conditions. The bacterial community analysis indicated that various kinds of microbial species exist in groundwater matrix. Phylogenetic tree analysis revealed that Proteobacteria was the dominant phylum, with Hydrogenophaga (34%), Limnohabitans (16%), and Simplicispira (7%) as the major bacterial genera. The nitrate respirers especially from the Hydrogenophaga genus anaerobically oxidized As(III) using nitrate as an electron acceptor instead of oxygen. Our study implied that microbes can facilitate the groundwater As oxidation using nitrate on the adsorptive media. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. 42 CFR 84.161 - Man test for gases and vapors; Type B and Type BE respirators; test requirements.

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Man test for gases and vapors; Type B and Type BE respirators; test requirements. 84.161 Section 84.161 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air...

  12. 42 CFR 84.160 - Man test for gases and vapors; Type A and Type AE respirators; test requirements.

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Man test for gases and vapors; Type A and Type AE respirators; test requirements. 84.160 Section 84.160 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air...

  13. A Low Cost Structurally Optimized Design for Diverse Filter Types

    Kazmi, Majida; Aziz, Arshad; Akhtar, Pervez; Ikram, Nassar

    2016-01-01

    A wide range of image processing applications deploys two dimensional (2D)-filters for performing diversified tasks such as image enhancement, edge detection, noise suppression, multi scale decomposition and compression etc. All of these tasks require multiple type of 2D-filters simultaneously to acquire the desired results. The resource hungry conventional approach is not a viable option for implementing these computationally intensive 2D-filters especially in a resource constraint environment. Thus it calls for optimized solutions. Mostly the optimization of these filters are based on exploiting structural properties. A common shortcoming of all previously reported optimized approaches is their restricted applicability only for a specific filter type. These narrow scoped solutions completely disregard the versatility attribute of advanced image processing applications and in turn offset their effectiveness while implementing a complete application. This paper presents an efficient framework which exploits the structural properties of 2D-filters for effectually reducing its computational cost along with an added advantage of versatility for supporting diverse filter types. A composite symmetric filter structure is introduced which exploits the identities of quadrant and circular T-symmetries in two distinct filter regions simultaneously. These T-symmetries effectually reduce the number of filter coefficients and consequently its multipliers count. The proposed framework at the same time empowers this composite filter structure with additional capabilities of realizing all of its Ψ-symmetry based subtypes and also its special asymmetric filters case. The two-fold optimized framework thus reduces filter computational cost up to 75% as compared to the conventional approach as well as its versatility attribute not only supports diverse filter types but also offers further cost reduction via resource sharing for sequential implementation of diversified image

  14. 42 CFR 84.157 - Airflow resistance test; Type C supplied-air respirator, pressure-demand class; minimum...

    2010-10-01

    ... test; Type C supplied-air respirator, pressure-demand class; minimum requirements. (a) The static... 42 Public Health 1 2010-10-01 2010-10-01 false Airflow resistance test; Type C supplied-air respirator, pressure-demand class; minimum requirements. 84.157 Section 84.157 Public Health PUBLIC HEALTH...

  15. Temperature and substrate controls on intra-annual variation in ecosystem respiration in two subarctic vegetation types

    Grogan, Paul; Jonasson, Sven Evert

    2005-01-01

    significantly to ecosystem respiration during most phases of winter and summer in the two vegetation types. Ecosystem respiration rates through the year did not differ significantly between vegetation types despite substantial differences in biomass pools, soil depth and temperature regime. Most (76...... contributions of bulk soil organic matter and plant-associated carbon pools to ecosystem respiration is critical to predicting the response of arctic ecosystem net carbon balance to climate change. In this study, we determined the variation in ecosystem respiration rates from birch forest understory and heath......-92%) of the intra-annual variation in ecosystem respiration rates from these two common mesic subarctic ecosystems was explained using a first-order exponential equation relating respiration to substrate chemical quality and soil temperature. Removal of plants and their current year's litter significantly reduced...

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

    2006-08-01

    flow rate through the test filter. The flow rate was measured using a mass flow meter (Series 4000, TSI, Shoreview, MN). Several modifications were made...operating conditions. This included assessing the effect of non- isokinetic sampling, flow calibrations, and characterization of the challenge...sampling bias on the measured penetrations due to the non- isokinetic sampling downstream. 3.3.2.2 System Characterization. Shakedown tests were

  17. Vegetation types alter soil respiration and its temperature sensitivity at the field scale in an estuary wetland.

    Guangxuan Han

    Full Text Available Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and investigated how the soil respiration and its temperature sensitivity are affected by the different vegetation (Phragmites australis, Suaeda salsa and bare soil in the Yellow River Estuary. During the growing season, there were significant linear relationships between soil respiration rates and shoot and root biomass, respectively. On the diurnal timescale, daytime soil respiration was more dependent on net photosynthesis. A positive correlation between soil respiration and net photosynthesis at the Phragmites australis site was found. There were exponential correlations between soil respiration and soil temperature, and the fitted Q10 values varied among different vegetation types (1.81, 2.15 and 3.43 for Phragmites australis, Suaeda salsa and bare soil sites, respectively. During the growing season, the mean soil respiration was consistently higher at the Phragmites australis site (1.11 µmol CO2 m(-2 s(-1, followed by the Suaeda salsa site (0.77 µmol CO2 m(-2 s(-1 and the bare soil site (0.41 µmol CO2 m(-2 s(-1. The mean monthly soil respiration was positively correlated with shoot and root biomass, total C, and total N among the three vegetation patches. Our results suggest that vegetation patchiness at a field scale might have a large impact on ecosystem-scale soil respiration. Therefore, it is necessary to consider the differences in vegetation types when using models to evaluate soil respiration in an estuary wetland.

  18. Vegetation Types Alter Soil Respiration and Its Temperature Sensitivity at the Field Scale in an Estuary Wetland

    Han, Guangxuan; Xing, Qinghui; Luo, Yiqi; Rafique, Rashad; Yu, Junbao; Mikle, Nate

    2014-01-01

    Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and investigated how the soil respiration and its temperature sensitivity are affected by the different vegetation (Phragmites australis, Suaeda salsa and bare soil) in the Yellow River Estuary. During the growing season, there were significant linear relationships between soil respiration rates and shoot and root biomass, respectively. On the diurnal timescale, daytime soil respiration was more dependent on net photosynthesis. A positive correlation between soil respiration and net photosynthesis at the Phragmites australis site was found. There were exponential correlations between soil respiration and soil temperature, and the fitted Q 10 values varied among different vegetation types (1.81, 2.15 and 3.43 for Phragmites australis, Suaeda salsa and bare soil sites, respectively). During the growing season, the mean soil respiration was consistently higher at the Phragmites australis site (1.11 µmol CO2 m−2 s−1), followed by the Suaeda salsa site (0.77 µmol CO2 m−2 s−1) and the bare soil site (0.41 µmol CO2 m−2 s−1). The mean monthly soil respiration was positively correlated with shoot and root biomass, total C, and total N among the three vegetation patches. Our results suggest that vegetation patchiness at a field scale might have a large impact on ecosystem-scale soil respiration. Therefore, it is necessary to consider the differences in vegetation types when using models to evaluate soil respiration in an estuary wetland. PMID:24608636

  19. 42 CFR 84.156 - Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements.

    2010-10-01

    ... C supplied-air respirator, demand class; minimum requirements. (a) Inhalation resistance shall not... 42 Public Health 1 2010-10-01 2010-10-01 false Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements. 84.156 Section 84.156 Public Health PUBLIC HEALTH SERVICE...

  20. Reduction of Carbon Dioxide in Filtering Facepiece Respirators with an Active-Venting System: A Computational Study.

    Erik Birgersson

    Full Text Available During expiration, the carbon dioxide (CO2 levels inside the dead space of a filtering facepiece respirator (FFR increase significantly above the ambient concentration. To reduce the CO2 concentration inside the dead space, we attach an active lightweight venting system (AVS comprising a one-way valve, a blower and a battery in a housing to a FFR. The achieved reduction is quantified with a computational-fluid-dynamics model that considers conservation of mass, momentum and the dilute species, CO2, inside the FFR with and without the AVS. The results suggest that the AVS can reduce the CO2 levels inside the dead space at the end of expiration to around 0.4% as compared to a standard FFR, for which the CO2 levels during expiration reach the same concentration as that of the expired alveolar air at around 5%. In particular, during inspiration, the average CO2 volume fraction drops to near-to ambient levels of around 0.08% with the AVS. Overall, the time-averaged CO2 volume fractions inside the dead space for the standard FFR and the one with AVS are around 3% and 0.3% respectively. Further, the ability of the AVS to vent the dead-space air in the form of a jet into the ambient - similar to the jets arising from natural expiration without a FFR - ensures that the expired air is removed and diluted more efficiently than a standard FFR.

  1. 42 CFR 84.162 - Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air...

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air respirators; test requirements. 84.162 Section 84.162 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL...

  2. Novel Control Strategy for VSI and CSI Active Filters and Comparing These Two Types of Filters

    Gholam Reza Arab

    2014-10-01

    Full Text Available Recently to eliminate the harmonics and improve the power factor of the power networks, much attention has been attracted to active filters. The advantages of these filters are lower volume and their better compensating characteristics than the passive filters. In conventional sliding mode controllers, the source current waveform is fluctuated in near to zero values. In this paper, using a new sliding technique, lower Total Harmonic Distortion (THD in source current is obtained and the current waveform is improved. As well as, two novel control strategies for two types of active filters, VSI and CSI is proposed and then these two types of filters are compared to reduce THD value of source current.The proposed controlled strategies are simulated by MATLAB/Simulink. The Simulation results confirm that the proposed strategies reduce the THD of source current more than other strategies, and active filter based on CSI has a better performance than active filter based on VSI with a dead time area (for avoiding short circuit of the source in high powers.

  3. Two weeks of metformin treatment enhances mitochondrial respiration in skeletal muscle of AMPK kinase dead but not wild type mice

    Kristensen, Jonas Møller; Larsen, Steen; Helge, Jørn Wulff

    2013-01-01

    signaling. We investigated this by two weeks of oral metformin treatment of muscle specific kinase dead a(2) (KD) AMPK mice and wild type (WT) littermates. We measured mitochondrial respiration and protein activity and expressions of key enzymes involved in mitochondrial carbohydrate and fat metabolism...... and oxidative phosphorylation. Mitochondrial respiration, HAD and CS activity, PDH and complex I-V and cytochrome c protein expression were all reduced in AMPK KD compared to WT tibialis anterior muscles. Surprisingly, metformin treatment only enhanced respiration in AMPK KD mice and thereby rescued...... the respiration defect compared to the WT mice. Metformin did not influence protein activities or expressions in either WT or AMPK KD mice.We conclude that two weeks of in vivo metformin treatment enhances mitochondrial respiration in the mitochondrial deficient AMPK KD but not WT mice. The improvement seems...

  4. Commentary Considerations for Recommending Extended Use and Limited Reuse of Filtering Facepiece Respirators in Health Care Settings

    Fisher, Edward M.; Shaffer, Ronald E.

    2015-01-01

    Public health organizations, such as the Centers for Disease Control and Prevention (CDC), are increasingly recommending the use of N95 filtering facepiece respirators (FFRs) in health care settings. For infection control purposes, the usual practice is to discard FFRs after close contact with a patient (“single use”). However, in some situations, such as during contact with tuberculosis patients, limited FFR reuse (i.e., repeated donning and doffing of the same FFR by the same person) is practiced. A related practice, extended use, involves wearing the same FFR for multiple patient encounters without doffing. Extended use and limited FFR reuse have been recommended during infectious disease outbreaks and pandemics to conserve FFR supplies. This commentary examines CDC recommendations related to FFR extended use and limited reuse and analyzes available data from the literature to provide a relative estimate of the risks of these practices compared to single use. Analysis of the available data and the use of disease transmission models indicate that decisions regarding whether FFR extended use or reuse should be recommended should continue to be pathogen- and event-specific. Factors to be included in developing the recommendations are the potential for the pathogen to spread via contact transmission, the potential that the event could result in or is currently causing a FFR shortage, the protection provided by FFR use, human factors, potential for self-inoculation, the potential for secondary exposures, and government policies and regulations. While recent findings largely support the previous recommendations for extended use and limited reuse in certain situations, some new cautions and limitations should be considered before issuing recommendations in the future. In general, extended use of FFRs is preferred over limited FFR reuse. Limited FFR reuse would allow the user a brief respite from extended wear times, but increases the risk of self-inoculation and

  5. Soil Microbial Biomass, Basal Respiration and Enzyme Activity of Main Forest Types in the Qinling Mountains

    Cheng, Fei; Peng, Xiaobang; Zhao, Peng; Yuan, Jie; Zhong, Chonggao; Cheng, Yalong; Cui, Cui; Zhang, Shuoxin

    2013-01-01

    Different forest types exert essential impacts on soil physical-chemical characteristics by dominant tree species producing diverse litters and root exudates, thereby further regulating size and activity of soil microbial communities. However, the study accuracy is usually restricted by differences in climate, soil type and forest age. Our objective is to precisely quantify soil microbial biomass, basal respiration and enzyme activity of five natural secondary forest (NSF) types with the same stand age and soil type in a small climate region and to evaluate relationship between soil microbial and physical-chemical characters. We determined soil physical-chemical indices and used the chloroform fumigation-extraction method, alkali absorption method and titration or colorimetry to obtain the microbial data. Our results showed that soil physical-chemical characters remarkably differed among the NSFs. Microbial biomass carbon (Cmic) was the highest in wilson spruce soils, while microbial biomass nitrogen (Nmic) was the highest in sharptooth oak soils. Moreover, the highest basal respiration was found in the spruce soils, but mixed, Chinese pine and spruce stands exhibited a higher soil qCO2. The spruce soils had the highest Cmic/Nmic ratio, the greatest Nmic/TN and Cmic/Corg ratios were found in the oak soils. Additionally, the spruce soils had the maximum invertase activity and the minimum urease and catalase activities, but the maximum urease and catalase activities were found in the mixed stand. The Pearson correlation and principle component analyses revealed that the soils of spruce and oak stands obviously discriminated from other NSFs, whereas the others were similar. This suggested that the forest types affected soil microbial properties significantly due to differences in soil physical-chemical features. PMID:23840671

  6. Microscale Electrolysis Using Coin-Type Lithium Batteries and Filter

    Kamata, Masahiro; Yajima, Seiko

    2013-01-01

    An educational experiment illustrates the electrolysis of water and copper chloride to middle school science students. The electrolysis cell is composed of filter paper soaked with Na[subscript 2]SO[subscript 4] or CuCl[subscript 2] aqueous solution sandwiched, along with a sheet of platinum foil, between two coin-type lithium batteries. When the…

  7. Beta-spectrometer with magnetic filter of mini orange type

    Gorozhankin, V.M.; Gromov, K.Ya.; Kalinnikov, V.G.; Sereeter, Z.; Fominykh, V.I.; Malikov, Sh.R.; Yuldashev, M.B.

    1997-01-01

    At the ISOL facility YASNAPP-2 a β-spectrometer with a magnetic filter of the miniorange type is constructed to measure γ-ray internal conversion coefficients. The magnetic filter of the mini orange type is an assemblage of permanent magnets creating a toroidal magnetic field perpendicular to the electron trajectories from the source to the Si(Li) detector. The chosen profile of the permanent magnets allowed electron registration in the defined energy energy interval with some transmission increase. There are two sets of permanent magnets of the different thickness. Varying the type and number of permanent magnets one can set the detected electron energy intervals in a 50-2500 keV range. The efficiency of the spectrometer was investigated for different assemblages of the mini orange magnet. The facility can be used for the e-γ coincidence investigation. (A.A.D.)

  8. Bitshuffle: Filter for improving compression of typed binary data

    Masui, Kiyoshi

    2017-12-01

    Bitshuffle rearranges typed, binary data for improving compression; the algorithm is implemented in a python/C package within the Numpy framework. The library can be used alongside HDF5 to compress and decompress datasets and is integrated through the dynamically loaded filters framework. Algorithmically, Bitshuffle is closely related to HDF5's Shuffle filter except it operates at the bit level instead of the byte level. Arranging a typed data array in to a matrix with the elements as the rows and the bits within the elements as the columns, Bitshuffle "transposes" the matrix, such that all the least-significant-bits are in a row, etc. This transposition is performed within blocks of data roughly 8kB long; this does not in itself compress data, but rearranges it for more efficient compression. A compression library is necessary to perform the actual compression. This scheme has been used for compression of radio data in high performance computing.

  9. Soil Respiration at Dominant Patch Types within a Managed Northern Wisconsin Landscape

    Eug& #233; nie Euskirchen; Jiquan Chen; Eric J. Gustafson; Siyan Ma; Siyan Ma

    2003-01-01

    Soil respiration (SR), a substantial component of the forest carbon budget, has been studied extensively at the ecosystem, regional, continental, and global scales, but little progress has been made toward understanding SR over managed forest landscapes. Soil respiration is often influenced by soil temperature (Ts), soil moisture (Ms...

  10. Diatomite Type Filters for Swimming Pools. Standard No. 9, Revised October, 1966.

    National Sanitation Foundation, Ann Arbor, MI.

    Pressure and vacuum diatomite type filters are covered in this standard. The filters herein described are intended to be designed and used specifically for swimming pool water filtration, both public and residential. Included are the basic components which are a necessary part of the diatomite type filter such as filter housing, element supports,…

  11. Challenge of N95 and P100 Filtering Facepiece Respirators with Particles Containing Viable H1N1

    2009-12-02

    test protocols have been previously described (2). Briefly, the LSAT is composed of 10-cm diameter stainless steel sanitary fittings and a 15-cm...coughing in Human Subjects. Journal of Aerosol Medicine 20:484-494. 15. WK19997: Standard test method for effectiveness of decontamination of air...facepiece respirator g gram(s) H1N1 a strain of influenza A identified by its hemagglutinin and neuraminindase Kr-85 a radioactive isotope of krypton

  12. Effects of uniformities of deposition of respirable particles on filters on determining their quartz contents by using the direct on-filter X-ray diffraction (DOF XRD) method.

    Chen, Ching-Hwa; Tsaia, Perng-Jy; Lai, Chane-Yu; Peng, Ya-Lian; Soo, Jhy-Charm; Chen, Cheng-Yao; Shih, Tung-Sheng

    2010-04-15

    In this study, field samplings were conducted in three workplaces of a foundry plant, including the molding, demolding, and bead blasting, respectively. Three respirable aerosol samplers (including a 25-mm aluminum cyclone, nylon cyclone, and IOSH cyclone) were used side-by-side to collect samples from each selected workplace. For each collected sample, the uniformity of the deposition of respirable dusts on the filter was measured and its free silica content was determined by both the DOF XRD method and NIOSH 7500 XRD method (i.e., the reference method). A same trend in measured uniformities can be found in all selected workplaces: 25-mm aluminum cyclone>nylon cyclone>IOSH cyclone. Even for samples collected by the sampler with the highest uniformity (i.e., 25-mm aluminum cyclone), the use of the DOF XRD method would lead to the measured free silica concentrations 1.15-2.89 times in magnitude higher than that of the reference method. A new filter holder should be developed with the minimum uniformity comparable to that of NIOSH 7500 XRD method (=0.78) in the future. The use of conversion factors for correcting quartz concentrations obtained from the DOF XRD method based on the measured uniformities could be suitable for the foundry industry at this stage. 2009 Elsevier B.V. All rights reserved.

  13. Effects of uniformities of deposition of respirable particles on filters on determining their quartz contents by using the direct on-filter X-ray diffraction (DOF XRD) method

    Chen, Ching-Hwa; Tsaia, Perng-Jy; Lai, Chane-Yu; Peng, Ya-Lian; Soo, Jhy-Charm; Chen, Cheng-Yao; Shih, Tung-Sheng

    2010-01-01

    In this study, field samplings were conducted in three workplaces of a foundry plant, including the molding, demolding, and bead blasting, respectively. Three respirable aerosol samplers (including a 25-mm aluminum cyclone, nylon cyclone, and IOSH cyclone) were used side-by-side to collect samples from each selected workplace. For each collected sample, the uniformity of the deposition of respirable dusts on the filter was measured and its free silica content was determined by both the DOF XRD method and NIOSH 7500 XRD method (i.e., the reference method). A same trend in measured uniformities can be found in all selected workplaces: 25-mm aluminum cyclone > nylon cyclone > IOSH cyclone. Even for samples collected by the sampler with the highest uniformity (i.e., 25-mm aluminum cyclone), the use of the DOF XRD method would lead to the measured free silica concentrations 1.15-2.89 times in magnitude higher than that of the reference method. A new filter holder should be developed with the minimum uniformity comparable to that of NIOSH 7500 XRD method (=0.78) in the future. The use of conversion factors for correcting quartz concentrations obtained from the DOF XRD method based on the measured uniformities could be suitable for the foundry industry at this stage.

  14. Insights Gained from the Dehalococcoides ethenogenes Strain 195’s Transcriptome Responding to a Wide Range of Respiration Rates and Substrate Types

    2012-04-01

    fermented yeast , pure hydrogen, or endogenous biomass decay). When similarly respiring (~120 ?eeq PCE/(L-hr)) batch and PSS cultures were contrasted, the...REPORT Insights gained from the “Dehalococcoides ethenogenes” strain 195?s transcriptome responding to a wide range of respiration rates and substrate...types. 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: Bacteria of the group “Dehalococcoides” display the ability to respire recalcitrant chlorinated

  15. Global variability in leaf respiration in relation to climate, plant functional types and leaf traits.

    Atkin, Owen K; Bloomfield, Keith J; Reich, Peter B; Tjoelker, Mark G; Asner, Gregory P; Bonal, Damien; Bönisch, Gerhard; Bradford, Matt G; Cernusak, Lucas A; Cosio, Eric G; Creek, Danielle; Crous, Kristine Y; Domingues, Tomas F; Dukes, Jeffrey S; Egerton, John J G; Evans, John R; Farquhar, Graham D; Fyllas, Nikolaos M; Gauthier, Paul P G; Gloor, Emanuel; Gimeno, Teresa E; Griffin, Kevin L; Guerrieri, Rossella; Heskel, Mary A; Huntingford, Chris; Ishida, Françoise Yoko; Kattge, Jens; Lambers, Hans; Liddell, Michael J; Lloyd, Jon; Lusk, Christopher H; Martin, Roberta E; Maksimov, Ayal P; Maximov, Trofim C; Malhi, Yadvinder; Medlyn, Belinda E; Meir, Patrick; Mercado, Lina M; Mirotchnick, Nicholas; Ng, Desmond; Niinemets, Ülo; O'Sullivan, Odhran S; Phillips, Oliver L; Poorter, Lourens; Poot, Pieter; Prentice, I Colin; Salinas, Norma; Rowland, Lucy M; Ryan, Michael G; Sitch, Stephen; Slot, Martijn; Smith, Nicholas G; Turnbull, Matthew H; VanderWel, Mark C; Valladares, Fernando; Veneklaas, Erik J; Weerasinghe, Lasantha K; Wirth, Christian; Wright, Ian J; Wythers, Kirk R; Xiang, Jen; Xiang, Shuang; Zaragoza-Castells, Joana

    2015-04-01

    Leaf dark respiration (Rdark ) is an important yet poorly quantified component of the global carbon cycle. Given this, we analyzed a new global database of Rdark and associated leaf traits. Data for 899 species were compiled from 100 sites (from the Arctic to the tropics). Several woody and nonwoody plant functional types (PFTs) were represented. Mixed-effects models were used to disentangle sources of variation in Rdark . Area-based Rdark at the prevailing average daily growth temperature (T) of each site increased only twofold from the Arctic to the tropics, despite a 20°C increase in growing T (8-28°C). By contrast, Rdark at a standard T (25°C, Rdark (25) ) was threefold higher in the Arctic than in the tropics, and twofold higher at arid than at mesic sites. Species and PFTs at cold sites exhibited higher Rdark (25) at a given photosynthetic capacity (Vcmax (25) ) or leaf nitrogen concentration ([N]) than species at warmer sites. Rdark (25) values at any given Vcmax (25) or [N] were higher in herbs than in woody plants. The results highlight variation in Rdark among species and across global gradients in T and aridity. In addition to their ecological significance, the results provide a framework for improving representation of Rdark in terrestrial biosphere models (TBMs) and associated land-surface components of Earth system models (ESMs). © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  16. Soil respiration at mean annual temperature predicts annual total across vegetation types and biomes

    M. Bahn

    2010-07-01

    Full Text Available Soil respiration (SR constitutes the largest flux of CO2 from terrestrial ecosystems to the atmosphere. However, there still exist considerable uncertainties as to its actual magnitude, as well as its spatial and interannual variability. Based on a reanalysis and synthesis of 80 site-years for 57 forests, plantations, savannas, shrublands and grasslands from boreal to tropical climates we present evidence that total annual SR is closely related to SR at mean annual soil temperature (SRMAT, irrespective of the type of ecosystem and biome. This is theoretically expected for non water-limited ecosystems within most of the globally occurring range of annual temperature variability and sensitivity (Q10. We further show that for seasonally dry sites where annual precipitation (P is lower than potential evapotranspiration (PET, annual SR can be predicted from wet season SRMAT corrected for a factor related to P/PET. Our finding indicates that it can be sufficient to measure SRMAT for obtaining a well constrained estimate of its annual total. This should substantially increase our capacity for assessing the spatial distribution of soil CO2 emissions across ecosystems, landscapes and regions, and thereby contribute to improving the spatial resolution of a major component of the global carbon cycle.

  17. The Effect of Wearing Different Types of Respirators on Postural Stability and Comfort

    Farhang Akbar-Khanzadeh; Sandra M. Woolley; Kent Huang

    2012-01-01

    Respirators are commonly used to protect workers against workplace airborne contaminants, but this equipment may become a safety hazard by creating discomfort, disorientation and postural instability.Although postural stability is critical to workers, especially those working near moving objects or on surfaces where a loss of balance may become life threatening, little attention has been given to the effect of respirators on wearers’ postural stability. The purpose of this study was to examin...

  18. Experiment on a multilayer type air filter for the filtration of sodium aerosol

    Otake, N.; Nozaki, O.

    1987-01-01

    An emergency air filter system of FBR was developed by using a multilayer type filter to protect the function of HEPA filter from clogging due to loading of sodium aerosol. To examine the effect of loading of sodium aerosol on the filter system, sodium aerosol consisting of sodium oxides and the related compound was supplied to the filter system. Several parameters to determine the effectiveness of the multilayer type filter were surveyed. It was confirmed that the emergency air filter system of FBR consisting of the multilayer type filter, a medium filter, HEPA filter with standard size (610 mm x 610 mm) in series could hold 800 g-Na at 1.5 kPa without clogging

  19. The Economics of Some Types of Absolute Filters

    Linder, P. J.; Skogulf, H. [Ab Atomenergi, Studsvir (Sweden)

    1968-12-15

    The cost of air-cleaning filters is determined by the purchase price of the filter and its mean life. If filter changes are not caused by a high level of activity, the increase in pressure drop will make a filter change necessary. In the latter case the dust-holding capacity of the filter determines the interval between changes. A number of different filters have been compared in this respect using atmospheric aerosols and a significant difference in cost has been observed. (author)

  20. CNTF-ACM promotes mitochondrial respiration and oxidative stress in cortical neurons through upregulating L-type calcium channel activity.

    Sun, Meiqun; Liu, Hongli; Xu, Huanbai; Wang, Hongtao; Wang, Xiaojing

    2016-09-01

    A specialized culture medium termed ciliary neurotrophic factor-treated astrocyte-conditioned medium (CNTF-ACM) allows investigators to assess the peripheral effects of CNTF-induced activated astrocytes upon cultured neurons. CNTF-ACM has been shown to upregulate neuronal L-type calcium channel current activity, which has been previously linked to changes in mitochondrial respiration and oxidative stress. Therefore, the aim of this study was to evaluate CNTF-ACM's effects upon mitochondrial respiration and oxidative stress in rat cortical neurons. Cortical neurons, CNTF-ACM, and untreated control astrocyte-conditioned medium (UC-ACM) were prepared from neonatal Sprague-Dawley rat cortical tissue. Neurons were cultured in either CNTF-ACM or UC-ACM for a 48-h period. Changes in the following parameters before and after treatment with the L-type calcium channel blocker isradipine were assessed: (i) intracellular calcium levels, (ii) mitochondrial membrane potential (ΔΨm), (iii) oxygen consumption rate (OCR) and adenosine triphosphate (ATP) formation, (iv) intracellular nitric oxide (NO) levels, (v) mitochondrial reactive oxygen species (ROS) production, and (vi) susceptibility to the mitochondrial complex I toxin rotenone. CNTF-ACM neurons displayed the following significant changes relative to UC-ACM neurons: (i) increased intracellular calcium levels (p ACM (p ACM promotes mitochondrial respiration and oxidative stress in cortical neurons through elevating L-type calcium channel activity.

  1. Application of phantom type compensating filter in tomography

    Okayama, A.; Mukae, H.; Itoh, M. (Yamaguchi Univ., Ube (Japan). School of Medicine)

    1981-01-01

    We reported a new device of phantom type compensating filters for pulmonary hilar tomography with polytome U at the 35th annual meeting of the Japanese Society of Radiological Technology. This report is to show application of this compensated method to the head, the hip joint and the lower thoracic spine in tomography. Using the filters optimal density can be obtained in all area of aim part on a X-ray film, and thus makes to get more information. 1) In the head clear shadow of pars nasalis, sinus paranasales and sella turcica is obtained. Destruction or defect of bone contour is easily detected. It is also useful to differentiate the disorders and to determine the expansivity of the lesion. 2) In the hip joint this method has advantages over the ordinary method. There is a few misdiagnosis in trochanteric lesions such as tuberculosis or bone tumor, because of high density at the trochanteric region in ordinary method, but in this method optimal density can be obtained, and misdiagnosis is improved. Soft tissue is sharply visualized, indicating usefulness in diagnosis of existence of hematoma or abscess. 3) In the lower thoracic vertebra it is useful to diagnosis of the thoracic spondylosis, tuberculous spondylitis and compression fracture of the vertebral body, since optimal density of the spine can be obtained. It is also quite useful to detect small ossifications in the vertebral foraman in ossification of the flavum ligament.

  2. Application of phantom type compensating filter in tomography

    Okayama, Akio; Mukae, Hideki; Itoh, Mitsuo

    1981-01-01

    We reported a new device of phantom type compensating filters for pulmonary hilar tomography with polytome U at the 35th annual meeting of the Japanese Society of Radiological Technology. This report is to show application of this compensated method to the head, the hip joint and the lower thoracic spine in tomography. Using the filters optimal density can be obtained in all area of aim part on a X-ray film, and thus makes to get more information. 1) In the head clear shadow of pars nasalis, sinus paranasales and sella turcica is obtained. Destruction or defect of bone contour is easily detected. It is also useful to differentiate the disorders and to determine the expansivity of the lesion. 2) In the hip joint this method has advantages over the ordinary method. There is a few misdiagnosis in trochanteric lesions such as tuberculosis or bone tumor, because of high density at the trochanteric region in ordinary method, but in this method optimal density can be obtained, and misdiagnosis is improved. Soft tissue is sharply visualized, indicating usefulness in diagnosis of existence of hematoma or abscess. 3) In the lower thoracic vertebra it is useful to diagnosis of the thoracic spondylosis, tuberculous spondylitis and compression fracture of the vertebral body, since optimal density of the spine can be obtained. It is also quite useful to detect small ossifications in the vertebral foraman in ossification of the flavum ligament. (author)

  3. Predicting inferior vena cava (IVC) filter retrievability using positional parameters: A comparative study of various filter types.

    Gotra, A; Doucet, C; Delli Fraine, P; Bessissow, A; Dey, C; Gallix, B; Boucher, L-M; Valenti, D

    2018-05-14

    To compare changes in inferior vena cava (IVC) filter positional parameters from insertion to removal and examine how they affect retrievability amongst various filter types. A total of 447 patients (260 men, 187 women) with a mean age of 55 years (range: 13-91 years) who underwent IVC filter retrieval between 2007-2014 were retrospectively included. Post-insertion and pre-retrieval angiographic studies were assessed for filter tilt, migration, strut wall penetration and retrieval outcomes. ANCOVA and multiple logistic regression models were used to analyze factors affecting retrieval success. Pairwise comparisons between filter types were performed. Of 488 IVC filter retrieval attempts, 94.1% were ultimately successful. The ALN filter had the highest mean absolute value of tilt (5.6 degrees), the Optease filter demonstrated the largest mean migration (-8.0mm) and the Bard G2 filter showed highest mean penetration (5.2mm). Dwell time of 0-90 days (OR, 11.1; P=0.01) or 90-180 days (OR, 2.6; P=0.02), net tilt of 10-15 degrees (OR 8.9; P=0.05), caudal migration of -10 to 0mm (OR, 3.46; P=0.03) and penetration less than 3mm (OR, 2.6; P=0.01) were positive predictors of successful retrievability. Higher odds of successful retrieval were obtained for the Bard G2X, Bard G2 and Cook Celect when compared to the ALN and Cordis Optease filters. Shorter dwell time, lower mean tilt, caudal migration and less caval wall penetration are positive predictors of successful IVC filter retrieval. Copyright © 2018 Société française de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  4. Regional anatomic differences in skeletal muscle mitochondrial respiration in type 2 diabetes and obesity

    Rabøl, R; Larsen, S; Højberg, P M V

    2010-01-01

    respiration and markers of mitochondrial content in skeletal muscle of arm and leg in patients with T2DM and obese control subjects. Patients: Ten patients with T2DM (age, 52.3 +/- 2.7 yr; body mass index, 30.1 +/- 1.2 kg/m(2)) (mean +/- se) were studied after a 2-wk washout period of oral antihyperglycemic...... agents. Ten control subjects (age, 54.3 +/- 2.8 yr; body mass index, 30.4 +/- 1.2 kg/m(2)) with normal fasting and 2-h oral glucose tolerance test blood glucose levels were also included. Main Outcome Measure: We measured mitochondrial respiration in saponin-treated skinned muscle fibers from biopsies...

  5. Filters in topology optimization based on Helmholtz‐type differential equations

    Lazarov, Boyan Stefanov; Sigmund, Ole

    2011-01-01

    The aim of this paper is to apply a Helmholtz‐type partial differential equation as an alternative to standard density filtering in topology optimization problems. Previously, this approach has been successfully applied as a sensitivity filter. The usual filtering techniques in topology...... from the neighbor subdomains is an expensive operation. The proposed filter technique requires only mesh information necessary for the finite element discretization of the problem. The main idea is to define the filtered variable implicitly as a solution of a Helmholtz‐type differential equation...

  6. Multi-stage type replacing method of iodine filter

    Kitamura, Masao; Kamiya, Kunio.

    1976-01-01

    Object: To effectively replace a filter into a removing device of radioactive impurities used in ventilation and air conditioning system or the like in an atomic power plant. Structure: A plurality of elements of a filter are arranged in series relative to fluid. In the first replacement, an ante-filter-element on inlet side of fluid is removed, and a post-filter-element is repositioned to that position of the ante-element. Then, a fresh element is newly mounted on that position of the post-element. Replacement after the second time may be effected by repeating the operation noted above. With this arrangement, the minimal value of collection efficiency at replacement of filter may be increased. (Ikeda, J.)

  7. Direct-on-Filter α-Quartz Estimation in Respirable Coal Mine Dust Using Transmission Fourier Transform Infrared Spectrometry and Partial Least Squares Regression.

    Miller, Arthur L; Weakley, Andrew Todd; Griffiths, Peter R; Cauda, Emanuele G; Bayman, Sean

    2017-05-01

    In order to help reduce silicosis in miners, the National Institute for Occupational Health and Safety (NIOSH) is developing field-portable methods for measuring airborne respirable crystalline silica (RCS), specifically the polymorph α-quartz, in mine dusts. In this study we demonstrate the feasibility of end-of-shift measurement of α-quartz using a direct-on-filter (DoF) method to analyze coal mine dust samples deposited onto polyvinyl chloride filters. The DoF method is potentially amenable for on-site analyses, but deviates from the current regulatory determination of RCS for coal mines by eliminating two sample preparation steps: ashing the sampling filter and redepositing the ash prior to quantification by Fourier transform infrared (FT-IR) spectrometry. In this study, the FT-IR spectra of 66 coal dust samples from active mines were used, and the RCS was quantified by using: (1) an ordinary least squares (OLS) calibration approach that utilizes standard silica material as done in the Mine Safety and Health Administration's P7 method; and (2) a partial least squares (PLS) regression approach. Both were capable of accounting for kaolinite, which can confound the IR analysis of silica. The OLS method utilized analytical standards for silica calibration and kaolin correction, resulting in a good linear correlation with P7 results and minimal bias but with the accuracy limited by the presence of kaolinite. The PLS approach also produced predictions well-correlated to the P7 method, as well as better accuracy in RCS prediction, and no bias due to variable kaolinite mass. Besides decreased sensitivity to mineral or substrate confounders, PLS has the advantage that the analyst is not required to correct for the presence of kaolinite or background interferences related to the substrate, making the method potentially viable for automated RCS prediction in the field. This study demonstrated the efficacy of FT-IR transmission spectrometry for silica determination in

  8. Effect of physical training on mitochondrial respiration and reactive oxygen species release in skeletal muscle in patients with obesity and type 2 diabetes

    Hey-Mogensen, Martin; Højlund, K; Vind, B F

    2010-01-01

    of obese participants with and without type 2 diabetes. METHODS: Type 2 diabetic men (n = 13) and control (n = 14) participants matched for age, BMI and physical activity completed 10 weeks of aerobic training. Pre- and post-training muscle biopsies were obtained before a euglycaemic...... in type 2 diabetic participants. Mitochondrial ROS release tended to be higher in participants with type 2 diabetes. CONCLUSIONS/INTERPRETATION: Aerobic training improves muscle respiration and intrinsic mitochondrial respiration in untrained obese participants with and without type 2 diabetes...

  9. Genome sequence of the organohalide-respiring Dehalogenimonas alkenigignens type strain (IP3-3(T)).

    Key, Trent A; Richmond, Dray P; Bowman, Kimberly S; Cho, Yong-Joon; Chun, Jongsik; da Costa, Milton S; Rainey, Fred A; Moe, William M

    2016-01-01

    Dehalogenimonas alkenigignens IP3-3(T) is a strictly anaerobic, mesophilic, Gram negative staining bacterium that grows by organohalide respiration, coupling the oxidation of H2 to the reductive dehalogenation of polychlorinated alkanes. Growth has not been observed with any non-polyhalogenated alkane electron acceptors. Here we describe the features of strain IP3-3(T) together with genome sequence information and its annotation. The 1,849,792 bp high-quality-draft genome contains 1936 predicted protein coding genes, 47 tRNA genes, a single large subunit rRNA (23S-5S) locus, and a single, orphan, small unit rRNA (16S) locus. The genome contains 29 predicted reductive dehalogenase genes, a large majority of which lack cognate genes encoding membrane anchoring proteins.

  10. Filtering device for primary coolant circuits in BWR type reactors

    Tajima, Fumio; Yamamoto, Tetsuo.

    1985-01-01

    Purpose: To obtain a filtering device with a large filtering area and requiring less space. Constitution: A condensate inlet for introducing condensates to be filtered of primary coolant circuits, a filtrate exit, a backwash water exit and a bent tube are disposed to a container, and a plurality of hollow thread membrane modules are suspended in the container. The condensates are caused to flow through the condensate inlet, filtered through the hollow thread membrane and then discharged from the filtrate exit. When the filtering treatment is proceeded to some extent, since solid contents captured in the hollow thread membranes are accumulated, a differential pressure is produced between the condensate inlet and the filtrate exit. When the differential pressure reaches a predetermined value, the backwash is conducted to discharge the liquid cleaning wastes through the backwash exit. The bent tube disposed to the container body is used for water and air draining. The hollow thread membranes are formed with porous resin such as of polyethylene. (Kawakami, Y.)

  11. Two-layer type filter for removal of radioactive iodine

    Taoki, M

    1976-04-16

    The object is to provide a filter for removing radioactive iodine, which is used for disposal of gaseous waste in an atomic power plant, to particularly hold a pressure loss lower. The filter according to the present invention comprises two layers, which are filled at a front stage with active carbon, which is small in pressure loss and has a good collective efficiency relative to iodine, and at a rear stage with silver zeolite, which has a good collective efficiency relative to both iodine and methyl iodine, whereby respective adsorbent are effectively utilized to minimize pressure loss even if a large quantity of air.

  12. Two-layer type filter for removal of radioactive iodine

    Taoki, Masafumi.

    1976-01-01

    Object: To provide a filter for removing radioactive iodine, which is used for disposal of gaseous waste in an atomic power plant, to particularly hold a pressure loss lower. Structure: The filter according to the present invention comprises two layers, which are filled at a front stage with active carbon, which is small in pressure loss and has a good collective efficiency relative to iodine, and at a rear stage with silver zeolite, which has a good collective efficiency relative to both iodine and methyl iodine, whereby respective adsorbent are effectively utilized to minimize pressure loss even if a large quantity of air. (Kamimura, M.)

  13. Opposite effects of pioglitazone and rosiglitazone on mitochondrial respiration in skeletal muscle of patients with type 2 diabetes

    Rabøl, R; Boushel, R; Almdal, T

    2010-01-01

    mitochondrial respiration per milligram muscle was measured in saponin-treated skinned muscle fibres using high-resolution respirometry. RESULTS: Mitochondrial respiration per milligram muscle was lower in T2DM compared to controls at baseline and decreased during ROSI treatment but increased during PIO...... of ROSI and PIO on mitochondrial respiration, and also show that insulin sensitivity can be improved independently of changes in mitochondrial respiration. We confirm that mitochondrial respiration is reduced in T2DM compared to age- and BMI-matched control subjects....

  14. Quantitative evaluation of the protective effect of respirators

    Murata, Mikio

    1983-01-01

    The present status and related problems of the quantitative evaluation method for respirator efficiency are generally reviewed. As the introduction, the special features of various types of respirators are summarized, and the basic concept of leakage and the protection factor are explained. As for the quantitative measurement of the protective efficiency, the features of various existing man-test methods such as NaCl aerosol man-test, DOP (dioctyl phthalate) man-test, and SF 6 gas man-test are reviewed and discussed. As the important problems associated with those man-tests, the following aspects are discussed. The measurement of the aerosol concentration within masks; the calculation method for the protection factor; the effect of beards. The examples of measuring the protection factor are also explained for the following respirator systems: half mask respirator with a high efficiency filter; full face mask respirator with a high efficiency filter; demand mode and pressure-demand mode respirators; and mound suit with suspenders. Finally, the outline of the manual of respiratory protection published by NRC in 1976 is briefly reviewed. (Aoki, K.)

  15. Sensitivity Filters In Topology Optimisation As A Solution To Helmholtz Type Differential Equation

    Lazarov, Boyan Stefanov; Sigmund, Ole

    2009-01-01

    The focus of the study in this article is on the use of a Helmholtz type differential equation as a filter for topology optimisation problems. Until now various filtering schemes have been utilised in order to impose mesh independence in this type of problems. The usual techniques require topology...... information about the neighbour sub-domains is an expensive operation. The proposed filtering technique requires only mesh information necessary for the finite element discretisation of the problem. The main idea is to define the filtered variable implicitly as a solution of a Helmholtz type differential...... equation with homogeneous Neumann boundary conditions. The properties of the filter are demonstrated for various 2D and 3D topology optimisation problems in linear elasticity, solved on sequential and parallel computers....

  16. The efficiency of Whatman Type ACG/B filter papers for methyl iodine retention in air

    Davis, R.E.; Williams, J.M.E.

    1965-11-01

    Experiments are described in which charcoal impregnated glass fibre filter papers Type ACG/B were exposed to methyl iodide vapour and the penetration determined for iodide loadings ranging from 2 x 10 - 7 to 2x10 - 1 μg/cm 2 of filter area. Air was subsequently passed through the filters, and at intervals the amount of methyl iodide remaining on them was determined. Penetrations during loading varied from 30% to 80%, but after 10 minutes elution all filters retained less than 5% of the methyl iodide originally present. (author)

  17. A kinetic study of biological Cr(VI) reduction in trickling filters with different filter media types

    Dermou, E.; Vayenas, D.V.

    2007-01-01

    Two pilot-scale trickling filters were used in order to estimate Cr(VI) reduction through biological mechanisms in biofilm reactors operated in SBR mode with recirculation using different filter media types, i.e. plastic media and calcitic gravel. The feed concentrations of Cr(VI) examined were about 5, 10, 20, 30, 50 and 100 mg/l, while the concentration of the organic carbon was constant at 400 mg/l, in order to avoid carbon limitations in the bulk liquid. Maximum reduction rates of 4.8 and 4.7 g Cr(VI)/d were observed for feed Cr(VI) concentration of about 5 mg Cr(VI)/l, for the filters with the plastic support material and the gravel media, respectively. The reduction rates were significantly affected by the feed Cr(VI) concentration in both bioreactors. A dual-enzyme kinetic model was used in order to describe Cr(VI) reduction by aerobically grown mixed cultures. Model predictions were found to correspond very closely to experimental quantitative observations of Cr(VI) reduction at both pilot-scale trickling filters used

  18. H- ion source using a localized virtual magnetic filter in the plasma electrode: type I LV magnetic filter

    Oka, Y.; Kaneko, O.; Tsumori, K.; Takeiri, Y.; Osakabe, M.; Kawamoto, T.; Asano, E.; Akiyama, R.

    1999-12-01

    A new multicusp H - ion source using a Localized Virtual magnetic filter of type I [Ref.6] in the plasma electrode is investigated. A multipole (MP) arrangement with a spacing of 10 mm of the magnet bars holds an extraction hole, optimizing the efficient production of high H - current, and at the same time only a small electron component was co-extracted with the H - ions. The local filter arrangement separates the beam electrons at a low energy. It is shown that the co-extracted total electron current is determined principally by the integrated magnetic field flux (Gcm) of the local filter with an extraction system at a constant extraction voltage. When the value of the Gcm is increased, the total electron component is reduced, while the H - electrical efficiency had a broad maximum around the optimized value of the Gcm. A thicker plasma electrode should be necessary for sufficient reduction of electron current. In pure hydrogen operation, the achieved current density of H - is 10 mA/cm 2 . When Cs was seeded in a filter optimized for pure volume mode H - production, the maximum H - current density obtained is 51 mA/cm 2 and the ratio I ele /H - is ∼0.4 without applying a bias potential. (author)

  19. Investigation of different types of filters for atmospheric trace elements analysis by three analytical techniques

    Ali, A.E.; Bacso, J.

    1996-01-01

    Different atmospheric aerosol samples were collected on three types of filters. Disks of both loaded and clean areas of each kind of filter were investigated by XRF, PIXE and Scanning Electron Microscope (SEM) methods. The blank concentration values of the elements Al, Si, P, S, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Br and Pb in the three types of filters are discussed. It is found that for trace elemental analysis, the Nuclepore membrane filters are the most suitable for sampling. These have much lower blank element concentration values than the glass fibres and ash free filters. It was found also that the PIXE method is a more reliable analytical technique for atmospheric aerosol particles than the other methods. (author). 20 refs., 3 figs., 3 tabs

  20. 42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand classes; test requirements. 84.163 Section 84.163 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...

  1. SART-Type Half-Threshold Filtering Approach for CT Reconstruction.

    Yu, Hengyong; Wang, Ge

    2014-01-01

    The [Formula: see text] regularization problem has been widely used to solve the sparsity constrained problems. To enhance the sparsity constraint for better imaging performance, a promising direction is to use the [Formula: see text] norm (0 < p < 1) and solve the [Formula: see text] minimization problem. Very recently, Xu et al. developed an analytic solution for the [Formula: see text] regularization via an iterative thresholding operation, which is also referred to as half-threshold filtering. In this paper, we design a simultaneous algebraic reconstruction technique (SART)-type half-threshold filtering framework to solve the computed tomography (CT) reconstruction problem. In the medical imaging filed, the discrete gradient transform (DGT) is widely used to define the sparsity. However, the DGT is noninvertible and it cannot be applied to half-threshold filtering for CT reconstruction. To demonstrate the utility of the proposed SART-type half-threshold filtering framework, an emphasis of this paper is to construct a pseudoinverse transforms for DGT. The proposed algorithms are evaluated with numerical and physical phantom data sets. Our results show that the SART-type half-threshold filtering algorithms have great potential to improve the reconstructed image quality from few and noisy projections. They are complementary to the counterparts of the state-of-the-art soft-threshold filtering and hard-threshold filtering.

  2. Hydrodynamic calculation of a filter sand bed type used in the containment venting systems

    Cuevas V, D.; Sainz M, E.; Ortiz V, J.

    2015-09-01

    The filtered venting of the containment has been adopted in European countries to mitigate the consequences of excess pressure containment during a severe accident. When venting has taken place, the fission products are released directly into the environment, unless a filter on the same path is placed, so that various types of filters are used to trap the fission products. The venting filters of the containment currently installed use different filtration technologies that involve more than one medium. Those using water as the first stage of filtration are called wet systems and are equipped with additional steps to remove water drops and fine aerosols emissions. And even they may also be equipped with an element containing certain absorption means for the filtration of gaseous iodine species. Other designs based on filtration of deep bed as the primary retention step; called dry filters, use filtration media of metal fiber, ceramic or sand to trap aerosols. This paper evaluates the hydraulic characteristics of the filter sand bed type designed by EDF as a candidate to be installed in the containment of BWR Mark II (type of primary containment of the nuclear power plant of Laguna Verde). The evaluation of filter sand bed type was performed using the software package of open source OpenFOAM. Models of each zone of the filtered device were generated and through a series of parametric calculations of computational fluid mechanics relevant hydrodynamic characteristics of the device were obtained, such as pressure drops against mass flow rate and pressure fields and speed at different operating conditions. On the other hand, the model validation of the sand bed filter when comparing the results of experimental tests on a sand column of PITEAS program (1985-1986) against OpenFOAM simulation was realized. The results are very close to those obtained experimentally. (Author)

  3. Metformin-treated patients with type 2 diabetes have normal mitochondrial complex I respiration

    Larsen, Steen; Rabøl, R; Hansen, C N

    2012-01-01

    The glucose-lowering drug metformin has been shown to inhibit complex I of the mitochondrial electron transport chain in skeletal muscle. To investigate this effect in vivo we studied skeletal muscle mitochondrial respiratory capacity and content from patients with type 2 diabetes treated...

  4. Global variability in leaf respiration in relation to climate, plant functional types and leaf traits

    Owen K. Atkin; Keith J. Bloomfield; Peter B. Reich; Mark G. Tjoelker; Gregory P. Asner; Damien Bonal; Gerhard Bonisch; Matt G. Bradford; Lucas A. Cernusak; Eric G. Cosio; Danielle Creek; Kristine Y. Crous; Tomas F. Domingues; Jeffrey S. Dukes; John J. G. Egerton; John R. Evans; Graham D. Farquhar; Nikolaos M. Fyllas; Paul P. G. Gauthier; Emanuel Gloor; Teresa E. Gimeno; Kevin L. Griffin; Rossella Guerrieri; Mary A. Heskel; Chris Huntingford; Franc_oise Yoko Ishida; Jens Kattge; Hans Lambers; Michael J. Liddell; Jon Lloyd; Christopher H. Lusk; Roberta E. Martin; Ayal P. Maksimov; Trofim C. Maximov; Yadvinder Malhi; Belinda E. Medlyn; Patrick Meir; Lina M. Mercado; Nicholas Mirotchnick; Desmond Ng; Ulo Niinemets; Odhran S. O’Sullivan; Oliver L. Phillips; Lourens Poorter; Pieter Poot; I. Colin Prentice; Norma Salinas; Lucy M. Rowland; Michael G. Ryan; Stephen Sitch; Martijn Slot; Nicholas G. Smith; Matthew H. Turnbull; Mark C. VanderWel; Fernando Valladares; Erik J. Veneklaas; Lasantha K. Weerasinghe; Christian Wirth; Ian J. Wright; Kirk R. Wythers; Jen Xiang; Shuang Xiang; Joana Zaragoza-Castells

    2015-01-01

    A challenge for the development of terrestrial biosphere models (TBMs) and associated land surface components of Earth system models (ESMs) is improving representation of carbon (C) exchange between terrestrial plants and the atmosphere, and incorporating biological variation arising from diversity in plant functional types (PFTs) and climate (Sitch et al.,...

  5. The two types of stethoscope systems for respiration system diagnostics of the human body

    Abashkin, Vladimir; Achimova, Elena

    2003-12-01

    An acoustic multimode fiber optic sensors for medical diagnostics based upon the shutter principle has been elaborated with semiconductor laser diode as light source. The construction and the method of component preparation are described. Other type of stethoscope is electrical one. Both stethoscopes are four channels. The kinetics and dynamic vibrations and sounds of the human body can be detected, acquired and then processing by personal computer for medical diagnostics.

  6. Neural Network-Based Passive Filtering for Delayed Neutral-Type Semi-Markovian Jump Systems.

    Shi, Peng; Li, Fanbiao; Wu, Ligang; Lim, Cheng-Chew

    2017-09-01

    This paper investigates the problem of exponential passive filtering for a class of stochastic neutral-type neural networks with both semi-Markovian jump parameters and mixed time delays. Our aim is to estimate the states by designing a Luenberger-type observer, such that the filter error dynamics are mean-square exponentially stable with an expected decay rate and an attenuation level. Sufficient conditions for the existence of passive filters are obtained, and a convex optimization algorithm for the filter design is given. In addition, a cone complementarity linearization procedure is employed to cast the nonconvex feasibility problem into a sequential minimization problem, which can be readily solved by the existing optimization techniques. Numerical examples are given to demonstrate the effectiveness of the proposed techniques.

  7. Measuring temperature dependence of soil respiration: importance of incubation time, soil type, moisture content and model fits

    Schipper, L. A.; Robinson, J.; O'Neill, T.; Ryburn, J.; Arcus, V. L.

    2015-12-01

    Developing robust models of the temperature response and sensitivity of soil respiration is critical for determining changes carbon cycling in response to climate change and at daily to annual time scales. Currently, approaches for measuring temperature dependence of soil respiration generally use long incubation times (days to weeks and months) at a limited number of incubation temperatures. Long incubation times likely allow thermal adaptation by the microbial population so that results are poorly representative of in situ soil responses. Additionally, too few incubation temperatures allows for the fit and justification of many different predictive equations, which can lead to inaccuracies when used for carbon budgeting purposes. We have developed a method to rapidly determine the response of soil respiration rate to wide range of temperatures. An aluminium block with 44 sample slots is heated at one end and cooled at the other to give a temperature gradient from 0 to 55°C at about one degree increments. Soil respiration is measured within 5 hours to minimise the possibility of thermal adaptation. We have used this method to demonstrate the similarity of temperature sensitivity of respiration for different soils from the same location across seasons. We are currently testing whether long-term (weeks to months) incubation alter temperature response and sensitivity that occurs in situ responses. This method is also well suited for determining the most appropriate models of temperature dependence and sensitivity of soil respiration (including macromolecular rate theory MMRT). With additional testing, this method is expected to be a more reliable method of measuring soil respiration rate for soil quality and modelling of soil carbon processes.

  8. Toxicokinetics and metabolisms of benzophenone-type UV filters in rats

    Jeon, Hee-Kyung; Sarma, Sailendra Nath; Kim, Youn-Jung; Ryu, Jae-Chun

    2008-01-01

    Sunscreens containing UV filters are recommended to reduce damage caused by solar UV radiation. Recently, benzophenone (BP)-type UV filters have become widely used as UV stabilizers in skin-moisturizing products and sunscreen lotions; however, very little information is available regarding the potential harmful effects of prolonged exposure to these compounds. Therefore, we investigated the toxicokinetics and metabolism of BP-type UV filters in rats using gas chromatography-mass spectrometry (GC-MS). To examine the metabolism of BP-type UV filters, we analyzed the parent compounds BP and 2-hydroxy-4-methoxybenzophenone (HMB). In rats, BP was mainly converted to benzhydrol (BH) and 4-hydroxybenzophenone (HBP) (i.e., type A UV filters). In contrast, HMB was converted into at least three intermediates, including 2,4-dihydroxybenzophenone (DHB), which was formed via o-demethylation and subsequently converted into 2,3,4-trihydroxybenzophenone (THB), and 2,2'-dihydroxy-4-methoxybenzophenone (DHMB), which formed via the aromatic hydroxylation of HMB (i.e., type B UV filters). Next, the toxicokinetic curve for BP showed a peak concentration (C max ) of 2.06 ± 0.46 μg/ml at approximately 4 h after BP administration. After a single oral dose of HMB, the C max of HMB reached 21.21 ± 11.61 μg/ml within 3 h (T max ), and then declined rapidly compared to the kinetic curve of BP. The concentration of these metabolites in rat blood decreased much more slowly over time compared to the parent compounds. Thus, our results indicate that such metabolites might have more significant adverse effects than the parent compounds over the long term

  9. Workplace field testing of the pressure drop of particulate respirators using welding fumes.

    Cho, Hyun-Woo; Yoon, Chung-Sik

    2012-10-01

    In a previous study, we concluded that respirator testing with a sodium chloride aerosol gave a conservative estimate of filter penetration for welding fume aerosols. A rapid increase in the pressure drop (PD) of some respirators was observed as fumes accumulated on the filters. The present study evaluated particulate respirator PD based on workplace field tests. A field PD tester was designed and validated using the TSI 8130 Automatic Filter Tester, designed in compliance with National Institute for Occupational and Safety and Health regulation 42 CFR part 84. Three models (two replaceable dual-type filters and one replaceable single-type filter) were evaluated against CO(2) gas arc welding on mild steel in confined booths in the workplace. Field tests were performed under four airborne concentrations (27.5, 15.4, 7.9, and 2.1 mg m(-3)). The mass concentration was measured by the gravimetric method, and number concentration was monitored using P-Trak (Model 8525, TSI, USA). Additionally, photos and scanning electron microscopy-energy dispersive X-ray spectroscopy were used to visualize and analyze the composition of welding fumes trapped in the filters. The field PD tester showed no significant difference compared with the TSI tester. There was no significant difference in the initial PD between laboratory and field results. The PD increased as a function of fume load on the respirator filters for all tested models. The increasing PD trend differed by models, and PD increased rapidly at high concentrations because greater amount of fumes accumulated on the filters in a given time. The increase in PD as a function of fume load on the filters showed a similar pattern as fume load varied for a particular model, but different patterns were observed for different models. Images and elemental analyses of fumes trapped on the respirator filters showed that most welding fumes were trapped within the first layer, outer web cover, and second layer, in order, while no fumes

  10. Iridescence and spectral filtering of the gyroid-type photonic crystals in Parides sesostris wing scales

    Wilts, Bodo D.; Michielsen, Kristel; De Raedt, Hans; Stavenga, Doekele G.

    2012-01-01

    The cover scales on the wing of the Emerald-patched Cattleheart butterfly, Parides sesostris, contain gyroid-type biological photonic crystals that brightly reflect green light. A pigment, which absorbs maximally at approximately 395 nm, is immersed predominantly throughout the elaborate upper lamina. This pigment acts as a long-pass filter shaping the reflectance spectrum of the underlying photonic crystals. The additional effect of the filtering is that the spatial distribution of the scale reflectance is approximately angle-independent, leading to a stable wing pattern contrast. The spectral tuning of the original reflectance is verified by photonic band structure modelling. PMID:24098853

  11. Do the results of respirable dust samples obtained from direct-on-filter X-ray diffraction, direct-on-filter infrared and indirect infrared (KBr pellet) methods correlate?

    Pretorius, C

    2010-11-01

    Full Text Available The objective of this study was to determine whether a correlation exists between the quartz results obtained from direct-on-filter X-ray Diffraction analysis, direct-on-filter Fourier-Transform Infrared analysis and indirect analysis (Potassium...

  12. 78 FR 18535 - Respirator Certification Fees

    2013-03-27

    ... facepiece respirators. The North American respiratory protection market generated revenues around $1,830 million in 2007, the most recent data available.\\4\\ A summary of market segmentation, by respirator type... management. Of the U.S. respirator market of products approved by NIOSH, approximately 35 percent of approval...

  13. Wiener's Loop Filter for PLL-Based Carrier Recovery of OQPSK and MSK-Type Modulations

    Arnaldo Spalvieri

    2008-01-01

    Full Text Available This letter considers carrier recovery for offset quadrature phase shift keying (OQPSK and minimum shift keying-type (MSK-type modulations based on phase-lock loop (PLL. The concern of the letter is the optimization of the loop filter of the PLL. The optimization is worked out in the light of Wiener's theory taking into account the phase noise affecting the incoming carrier, the additive white Gaussian noise that is present on the channel, and the self-noise produced by the phase detector. Delay in the loop, which may affect the numerical implementation of the PLL, is also considered. Closed-form expressions for the loop filter and for the mean-square error are given for the case where the phase noise is characterized as a first-order process.

  14. Urinary concentrations of benzophenone-type ultra violet light filters and reproductive parameters in young men

    Adoamnei, Evdochia; Mendiola, Jaime; Moñino-García, Miriam

    2018-01-01

    positively associated with T/E2 (β = 0.04, 95%CI: 0.002; 0.07) and negatively with inhibin b/FSH (β = -0.11, 95%CI: -0.21; -0.006) ratio. No significant associations were found between other urinary BP-type UV filters and other reproductive hormone levels or between any semen parameters and any...

  15. Junction-type photonic crystal waveguides for notch- and pass-band filtering

    Shahid, Naeem

    2011-01-01

    Evolution of the mode gap and the associated transmission mini stop-band (MSB) as a function of photonic crystal (PhC) waveguide width is theoretically and experimentally investigated. The change of line-defect width is identified to be the most appropriate way since it offers a wide MSB wavelength tuning range. A high transmission narrow-band filter is experimentally demonstrated in a junction-type waveguide composed of two PhC waveguides with slightly different widths. The full width at half maximum is 5.6 nm; the peak transmission is attenuated by only ∼5 dB and is ∼20 dB above the MSBs. Additionally, temperature tuning of the filter were also performed. The results show red-shift of the transmission peak and the MSB edges with a gradient of dλ/dT = 0.1 nm/°C. It is proposed that the transmission MSBs in such junction-type cascaded PhC waveguides can be used to obtain different types of filters. © 2011 Optical Society of America.

  16. Pseudobrookite-type MgTi2O5 water purification filter with controlled particle morphology

    Yuta Nakagoshi

    2015-09-01

    Full Text Available Pseudobrookite-type oxide-based ceramics, such as Al2TiO5 and MgTi2O5, have recently been studied as porous ceramic membranes. Here, the effect of LiF doping on the morphology of MgTi2O5 particles is presented in detail. Water purification filters were produced using porous MgTi2O5, with different particle morphologies. MgCO3 (basic and TiO2 powders with various LiF contents were wet-ball milled, dried, and then, calcined in air at 1100 °C to obtain the MgTi2O5 powders. The powder compacts were sintered at 1000–1200 °C to produce the MgTi2O5 disk filters. The 0.5 wt.% LiF-doped MgTi2O5 disk filter, with elongated grains, showed well-balanced performance removing boehmite particles with diameter of 0.7 μm. Non-doped MgTi2O5 disk filter with equiaxed grains was suitable for precise filtration.

  17. Filter bag De-NOx system with powder type catalysts at low temperature

    Kim, Byung-Hwan; Kim, Jeong-Heon; Kang, Pil-Sun; Yoo, Seung-Kwan; Yoon, Kyoon-Duk

    2010-01-01

    Combustion of carbon source materials (MSW, RDF, sludge, coal etc.) leads to the emission of harmful gaseous pollutants such as SO x , NO x , mercury, particulate matter, and dioxins etc. In particular, the emission of nitrogen oxides (NO x ) from the solid waste incinerator remains a serious air pollution problem. The previous research concerns have focused mainly on NO x reduction of stationary sources at high temperature SCR or SNCR process. Selective catalytic reduction (SCR) with NH 3 is the most widespread system used to control NO x emissions. However, this process suffers from several disadvantages due to the use of thermo fragile honeycomb type module and high temperature (about 300 degree Celsius) operation which consumes additional heating energy. To overcome this hurdle, filter bag De-NO x system with powder type catalysts at low temperature (less than 200 degree Celsius) has been under investigation in recent years and looks interesting because neither additional heat nor honeycomb type modules are required. Filter bag and powder type catalysts are cheap and effective materials to remove NO x at low temperature. In this study, the selective catalytic reduction of NO x was carried out on a filter support reactor with 300 mesh powder type catalysts at low temperature. The experiments were performed by powder type MnO x and V 2 O 5 / TiO 2 catalyst at low temperature ranging between 130 and 250 degree Celsius. Also, the effect of SO 2 and H 2 O on the NO conversion was investigated under our test conditions. The powder type catalysts were characterized by X-ray photoelectron spectrum (XPS) for measuring the state of oxygen on the catalyst surface and X-ray diffraction (XRD). It was observed that NO conversion of the powder type V 2 O 5 / TiO 2 catalyst was 85 % at 200 degree Celsius under presence of oxygen and that of MnO x was 50 % at the same condition. From these results, the powder type V 2 O 5 / TiO 2 catalyst showed an excellent performance on the

  18. The effects of two types of sleep deprivation on visual working memory capacity and filtering efficiency.

    Sean P A Drummond

    Full Text Available Sleep deprivation has adverse consequences for a variety of cognitive functions. The exact effects of sleep deprivation, though, are dependent upon the cognitive process examined. Within working memory, for example, some component processes are more vulnerable to sleep deprivation than others. Additionally, the differential impacts on cognition of different types of sleep deprivation have not been well studied. The aim of this study was to examine the effects of one night of total sleep deprivation and 4 nights of partial sleep deprivation (4 hours in bed/night on two components of visual working memory: capacity and filtering efficiency. Forty-four healthy young adults were randomly assigned to one of the two sleep deprivation conditions. All participants were studied: 1 in a well-rested condition (following 6 nights of 9 hours in bed/night; and 2 following sleep deprivation, in a counter-balanced order. Visual working memory testing consisted of two related tasks. The first measured visual working memory capacity and the second measured the ability to ignore distractor stimuli in a visual scene (filtering efficiency. Results showed neither type of sleep deprivation reduced visual working memory capacity. Partial sleep deprivation also generally did not change filtering efficiency. Total sleep deprivation, on the other hand, did impair performance in the filtering task. These results suggest components of visual working memory are differentially vulnerable to the effects of sleep deprivation, and different types of sleep deprivation impact visual working memory to different degrees. Such findings have implications for operational settings where individuals may need to perform with inadequate sleep and whose jobs involve receiving an array of visual information and discriminating the relevant from the irrelevant prior to making decisions or taking actions (e.g., baggage screeners, air traffic controllers, military personnel, health care

  19. The effects of two types of sleep deprivation on visual working memory capacity and filtering efficiency.

    Drummond, Sean P A; Anderson, Dane E; Straus, Laura D; Vogel, Edward K; Perez, Veronica B

    2012-01-01

    Sleep deprivation has adverse consequences for a variety of cognitive functions. The exact effects of sleep deprivation, though, are dependent upon the cognitive process examined. Within working memory, for example, some component processes are more vulnerable to sleep deprivation than others. Additionally, the differential impacts on cognition of different types of sleep deprivation have not been well studied. The aim of this study was to examine the effects of one night of total sleep deprivation and 4 nights of partial sleep deprivation (4 hours in bed/night) on two components of visual working memory: capacity and filtering efficiency. Forty-four healthy young adults were randomly assigned to one of the two sleep deprivation conditions. All participants were studied: 1) in a well-rested condition (following 6 nights of 9 hours in bed/night); and 2) following sleep deprivation, in a counter-balanced order. Visual working memory testing consisted of two related tasks. The first measured visual working memory capacity and the second measured the ability to ignore distractor stimuli in a visual scene (filtering efficiency). Results showed neither type of sleep deprivation reduced visual working memory capacity. Partial sleep deprivation also generally did not change filtering efficiency. Total sleep deprivation, on the other hand, did impair performance in the filtering task. These results suggest components of visual working memory are differentially vulnerable to the effects of sleep deprivation, and different types of sleep deprivation impact visual working memory to different degrees. Such findings have implications for operational settings where individuals may need to perform with inadequate sleep and whose jobs involve receiving an array of visual information and discriminating the relevant from the irrelevant prior to making decisions or taking actions (e.g., baggage screeners, air traffic controllers, military personnel, health care providers).

  20. A study of glasses-type color CGH using a color filter considering reduction of blurring

    Iwami, Saki; Sakamoto, Yuji

    2009-02-01

    We have developed a glasses-type color computer generated hologram (CGH) by using a color filter. The proposed glasses consist of two "lenses" made of overlapping holograms and color filters. The holograms, which are calculated to reconstruct images in each primary color, are divided to small areas, which we called cells, and superimposed on one hologram. In the same way, colors of the filter correspond to the hologram cells. We can configure it very simply without a complex optical system, and the configuration yields a small and light weight system suitable for glasses. When the cell is small enough, the colors are mixed and reconstructed color images are observed. In addition, color expression of reconstruction images improves, too. However, using small cells blurrs reconstructed images because of the following reasons: (1) interference between cells because of the correlation with the cells, and (2) reduction of resolution caused by the size of the cell hologram. We are investigating in order to make a hologram that has high resolution reconstructed color images without ghost images. In this paper, we discuss (1) the details of the proposed glasses-type color CGH, (2) appropriate cell size for an eye system, (3) effects of cell shape on the reconstructed images, and (4) a new method to reduce the blurring of the images.

  1. 42 CFR 84.134 - Respirator containers; minimum requirements.

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84.134... Respirators § 84.134 Respirator containers; minimum requirements. Supplied-air respirators shall be equipped with a substantial, durable container bearing markings which show the applicant's name, the type and...

  2. 42 CFR 84.197 - Respirator containers; minimum requirements.

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84.197... Cartridge Respirators § 84.197 Respirator containers; minimum requirements. Respirators shall be equipped with a substantial, durable container bearing markings which show the applicant's name, the type and...

  3. 42 CFR 84.174 - Respirator containers; minimum requirements.

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84.174... Air-Purifying Particulate Respirators § 84.174 Respirator containers; minimum requirements. (a) Except..., durable container bearing markings which show the applicant's name, the type of respirator it contains...

  4. Random Access for Machine-Type Communication based on Bloom Filtering

    Pratas, Nuno; Stefanovic, Cedomir; Madueño, Germán Corrales

    2016-01-01

    utilizes the system resources more efficiently and achieves similar or lower latency of connection establishment in case of synchronous arrivals, compared to the variant of the LTE-A access protocol that is optimized for MTC traffic. A dividend of the proposed method is that allows the base station (BS......We present a random access method inspired on Bloom filters that is suited for Machine-Type Communications (MTC). Each accessing device sends a signature during the contention process. A signature is constructed using the Bloom filtering method and contains information on the device identity...... and the connection establishment cause. We instantiate the proposed method over the current LTE-A access protocol. However, the method is applicable to a more general class of random access protocols that use preambles or other reservation sequences, as expected to be the case in 5G systems. We show that our method...

  5. Contrasting responses of soil respiration and temperature sensitivity to land use types: Cropland vs. apple orchard on the Chinese Loess Plateau.

    Wang, Rui; Sun, Qiqi; Wang, Ying; Zheng, Wei; Yao, Lunguang; Hu, Yaxian; Guo, Shengli

    2018-04-15

    Land use plays an essential role in regional carbon cycling, potentially influencing the exchange rates of CO 2 flux between soil and the atmosphere in terrestrial ecosystems. Temperature sensitivity of soil respiration (Q 10 ), as an efficient parameter to reflect the possible feedback between the global carbon cycle and climate change, has been extensively studied. However, very few reports have assessed the difference in temperature sensitivity of soil respiration under different land use types. In this study, a three-year field experiment was conducted in cropland (winter wheat, Triticum aestivum L.) and apple orchard (Malus domestica Borkh) on the semi-arid Loess Plateau from 2011 to 2013. Soil respiration (measured using Li-Cor 8100), bacterial community structure (represented by 16S rRNA), soil enzyme activities, and soil physicochemical properties of surface soil were monitored. The average annual soil respiration rate in the apple orchard was 12% greater than that in the cropland (2.01 vs. 1.80μmolm -2 s -1 ), despite that the average Q 10 values in the apple orchard was 15% lower than that in the cropland (ranging from 1.63 to 1.41). As to the differences among predominant phyla, Proteobacteria was 26% higher in the apple orchard than that in the cropland, whereas Actinobacteria and Acidobacteria were 18% and 36% lower in the apple orchard. The β-glucosidase and cellobiohydrolase activity were 15% (44.92 vs. 39.09nmolh -1 g -1 ) and 22% greater (21.39 vs. 17.50nmolh -1 g -1 ) in the apple orchard than that in the cropland. Compared to the cropland, the lower Q 10 values in the apple orchard resulted from the variations of bacterial community structure and β-glucosidase and cellobiohydrolase activity. In addition, the lower C: N ratios in the apple orchard (6.50 vs. 8.40) possibly also contributed to its lower Q 10 values. Our findings call for further studies to include the varying effects of land use types into consideration when applying Q 10 values

  6. High-Input Impedance Voltage-Mode Multifunction Filter with Four Grounded Components and Only Two Plus-Type DDCCs

    Hua-Pin Chen

    2010-01-01

    Full Text Available This paper introduces a novel voltage-mode multifunction biquadratic filter with single input and four outputs using two plus-type differential difference current conveyors (DDCCs and four grounded passive components. The filter can realize inverting highpass, inverting bandpass, noninverting lowpass, and noninverting bandpass filter responses, simultaneously. It still maintains the following advantages: (i using grounded capacitors attractive for integration and absorbing shunt parasitic capacitance, (ii using grounded resistors at all X terminals of DDCCs suitable for the variations of filter parameters and absorbing series parasitic resistances at all X terminals of DDCCs, (iii high-input impedance good for cascadability, (iv no need to change the filter topology, (v no need to component-matching conditions, (vi low active and passive sensitivity performances, and (vii simpler configuration due to the use of plus-type DDCCs only. HSPICE and MATLAB simulations results are provided to demonstrate the theoretical analysis.

  7. Recent progress in energy-filtered high energy X-ray photoemission electron microscopy using a Wien filter type energy analyzer

    Niimi, H.; Tsutsumi, T.; Matsudaira, H.; Kawasaki, T.; Suzuki, S.; Chun, W.-J.; Kato, M.; Kitajima, Y.; Iwasawa, Y.; Asakura, K.

    2004-01-01

    Energy-filtered X-ray photoemission electron microscopy (EXPEEM) is a microscopy technique which has the potential to provide surface chemical mapping during surface chemical processes on the nanometer scale. We studied the possibilities of EXPEEM using a Wien filter type energy analyzer in the high energy X-ray region above 1000 eV. We have successfully observed the EXPEEM images of Au islands on a Ta sheet using Au 3d 5/2 and Ta 3d 5/2 photoelectron peaks which were excited by 2380 eV X-rays emitted from an undulator (BL2A) at Photon Factory. Our recent efforts to improve the sensitivity of the Wien filter energy analyzer will also be discussed

  8. Analysis of the implementation of a sand bed type filter for the venting of a nuclear power plant

    Cuevas V, D.; Sainz M, E.; Ortiz V, J.

    2017-09-01

    The filtered venting of the containment has been adopted in European countries to mitigate the consequences derived from the excess pressure of the containment during a severe accident. When venting has taken place, the fission products are released directly into the environment, unless a filter is placed in the path of the same, so various types of filters are used to trap the fission products. The containment venting filters currently installed use different filtering technologies that involve more than one medium. Those who use water as the first stage of filtration are called wet systems, are equipped with additional stages to eliminate water drops and emissions of fine aerosols, and may even be equipped with an element that contains certain means of absorption for the gaseous iodine species filtration. Other designs, based on deep bed filtration as the main retention stage, called dry filters; use metal fiber, ceramic or sand filtration media to trap aerosols. The present work evaluates the hydraulic characteristics of the sand bed type filter designed by EDF as a candidate to be installed in the containment of the BWR Mark II (primary containment type of the Laguna Verde nuclear power plant). The evaluation of the sand bed filter was performed using the OpenFOAM open source software package. Models of each zone of the filtering device were generated and by means of a series of parametric calculations of computational fluid mechanics, the relevant hydrodynamic characteristics of the device were obtained, such as pressure drops against mass flow and pressure fields and velocity under different operating conditions. On the other hand, the validation of the sand bed filter model was made when comparing the results of experimental tests carried out in a sand column of the PITEAS program (1985-1986) against the simulation in OpenFOAM. The results obtained are very close to those obtained experimentally. (Author)

  9. Method of removing suspended impurity from mixed floor type filtering desalter

    Oya, Takashi; Morikawa, Yoshitake; Hagiwara, Masahiro; Kozu, Hideo; Izumi, Takeshi.

    1989-01-01

    In BWR type nuclear power plants, since the inside of a nuclear reactor has to be always kept clean, condensates flowing from a condensator to the inside of the reactor are cleaned-up by a condensate desalting tower into a highly cleaned-up state and then utilized as coolants for the inside of the reactor. Upon processing primary coolants, a mixed floor is formed with a resin in which the crosslinking rate of granular or powdery cationic exchange resins is reduced as from 7.5 to 3% of divinyl benzene (DVB) content. Crud separating effect is larger as the DVB content (%) is lower. However, if the DVB content is too small fracture strength and heat exchange capacity of the resins are decreased making it difficult for handling and, accordingly, practical lower limit is set to 3%. This enables sufficient removal of cruds upon eliminating suspended impurities in a mixed floor type filtering desalter. (T.M.)

  10. Development of an Advanced Respirator Fit Test Headform (Postprint)

    2012-11-01

    N95 filtering facepiece respirators (FFRs) for pro - tection studies against viable airborne particles. A Static (i.e., non-moving, non-speaking...requiredto wear respirators to reduce their exposure to air- borne hazards.(1) The U.S. Occupational Safety and Health Administration ( OSHA ) Respiratory...13 workplace protection factors.(9,10). Inward leakage (IL) of con - taminants into a respirator facepiece has been described as a combination of

  11. High-performance feedback-type active damping of LCL-filtered voltage source converters

    Wang, Xiongfei; Blaabjerg, Frede; Loh, Poh Chiang

    2015-01-01

    a generalized impedance-based model of grid current control with feedback-type active damping. Then, a controller design method based on the z-domain root contours and frequency-domain passivity theorem is proposed. It not only allows a co-design of the grid current controller and damping controller......Active damping of LCL-filter resonance based on single-state feedback control is widely used with voltage source converters. Its robustness against grid impedance variation has always been a major concern with its controller design. To deal with this issue, this paper begins by developing......, but ensures also a robust stabilization against the grid parameters variations. For illustration, the approach is applied to design three single-state feedback-damping schemes, and their damping robustness are compared under both inductive and resonant grid impedances. Experimental results validate...

  12. Benzonphenone-type UV filters in urine of Chinese young adults: Concentration, source and exposure

    Gao, Chong-jing; Liu, Li-yan; Ma, Wan-li; Zhu, Ning-zheng; Jiang, Ling; Li, Yi-Fan; Kannan, Kurunthachalam

    2015-01-01

    Benzophenone (BP)-type UV filters are commonly used in our daily life. 2-hydroxy-4-methoxy benzophenone (BP-3), 4-hydroxy benzophenone (4-HBP), 2,4-dihydroxy benzophenone (BP-1), 2,2′,4,4′-tetrahydroxy benzophenone (BP-2) and 2,2′-dihydroxy-4-methoxy benzophenone (BP-8) were measured in urine samples from Chinese young adults. The results indicated that Chinese young adults were widely exposed to BP-3, BP-1, and 4-HBP, with the median concentrations of 0.55, 0.21, and 0.08 ng/mL, respectively. No significant difference was found between males and females, between urban and rural population. The correlations between urinary concentrations provided important indications for sources and metabolic pathways of target compounds. The estimated daily excretion doses of BP-3, 4-HBP, BP-1, BP-2 and BP-8 were 27.2, 2.24, 5.86, 0.76 and 0.30 ng/kg-bw/day, respectively. The ratio of exposure to excretion must be considered for the exposure assessment with chemicals based on urine measurement. This is the first nationwide study on BP-derivatives with young adults in China. - Highlights: • Five BP-derivatives in urine were analyzed for Chinese young adults over China. • No difference was found between males and females, between urban and rural groups. • Concentration correlation provide indications for sources and metabolic pathways. • Ratio of exposure to excretion must be considered for the exposure assessment. - Benzophenone (BP)-type UV filters were frequently detected in urine samples from Chinese young adults, indicating their wide applications in China

  13. Transformation of benzophenone-type UV filters by chlorine: Kinetics, products identification and toxicity assessments

    Li, Jian; Ma, Li-yun; Xu, Li

    2016-01-01

    Highlights: • Chlorination kinetics of three benzophenone-type UV filters (BPs) was studied. • Chlorination of BPs followed second-order reaction. • The transformation products (TPs) of six BPs were identified. • Several transformation pathways were proposed. • Mostly enhanced toxicity of TPs after chlorination was observed. - Abstract: The present study focused on the kinetics, transformation pathways and toxicity of several benzophenone-type ultraviolet filters (BPs) during the water chlorination disinfection process. The transformation kinetics of the studied three BPs was found to be second-order reaction, which was dependent on the concentration of BPs and chlorine. The second-order rate constants increased from 86.7 to 975 M"−"1 s"−"1 for oxybenzone, 49.6–261.7 M"−"1 s"−"1 for 4-hydroxybenzophenone and 51.7–540 M"−"1 s"−"1 for 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid with the increasing pH value from 6 to 8 of the chlorination disinfection condition. Then the transformation products (TPs) of these BPs were identified by HPLC-QTof analysis. Several transformation pathways, including electrophilic substitution, methoxyl substitution, ketone groups oxidation, hydrolysis, decarboxylation and ring cleavage reaction, were speculated to participate in the chlorination transformation process. Finally, according to the toxicity experiment on luminescent bacteria, Photobacterium phosphoreum, enhanced toxicity was observed for almost all the TPs of the studied BPs except for 2,2′-dihydroxy-4,4′-dimethoxybenzophenone; it suggested the formation of TPs with more toxic than the parent compounds during the chlorination process. The present study provided a foundation to understand the transformation of BPs during chlorination disinfection process, and was of great significance to the drinking water safety.

  14. Transformation of benzophenone-type UV filters by chlorine: Kinetics, products identification and toxicity assessments

    Li, Jian; Ma, Li-yun; Xu, Li, E-mail: xulpharm@mails.tjmu.edu.cn

    2016-07-05

    Highlights: • Chlorination kinetics of three benzophenone-type UV filters (BPs) was studied. • Chlorination of BPs followed second-order reaction. • The transformation products (TPs) of six BPs were identified. • Several transformation pathways were proposed. • Mostly enhanced toxicity of TPs after chlorination was observed. - Abstract: The present study focused on the kinetics, transformation pathways and toxicity of several benzophenone-type ultraviolet filters (BPs) during the water chlorination disinfection process. The transformation kinetics of the studied three BPs was found to be second-order reaction, which was dependent on the concentration of BPs and chlorine. The second-order rate constants increased from 86.7 to 975 M{sup −1} s{sup −1} for oxybenzone, 49.6–261.7 M{sup −1} s{sup −1} for 4-hydroxybenzophenone and 51.7–540 M{sup −1} s{sup −1} for 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid with the increasing pH value from 6 to 8 of the chlorination disinfection condition. Then the transformation products (TPs) of these BPs were identified by HPLC-QTof analysis. Several transformation pathways, including electrophilic substitution, methoxyl substitution, ketone groups oxidation, hydrolysis, decarboxylation and ring cleavage reaction, were speculated to participate in the chlorination transformation process. Finally, according to the toxicity experiment on luminescent bacteria, Photobacterium phosphoreum, enhanced toxicity was observed for almost all the TPs of the studied BPs except for 2,2′-dihydroxy-4,4′-dimethoxybenzophenone; it suggested the formation of TPs with more toxic than the parent compounds during the chlorination process. The present study provided a foundation to understand the transformation of BPs during chlorination disinfection process, and was of great significance to the drinking water safety.

  15. Cardiac, Skeletal, and smooth muscle mitochondrial respiration

    Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I

    2014-01-01

    , skeletal, and smooth muscle was harvested from a total of 22 subjects (53±6 yrs) and mitochondrial respiration assessed in permeabilized fibers. Complex I+II, state 3 respiration, an index of oxidative phosphorylation capacity, fell progressively from cardiac, skeletal, to smooth muscle (54±1; 39±4; 15......±1 pmol•s(-1)•mg (-1), prespiration rates were normalized by CS (respiration...... per mitochondrial content), oxidative phosphorylation capacity was no longer different between the three muscle types. Interestingly, Complex I state 2 normalized for CS activity, an index of non-phosphorylating respiration per mitochondrial content, increased progressively from cardiac, skeletal...

  16. Soil respiration patterns for four major land-use types of the agro-pastoral region of northern China

    Land-use types and management practices are critical factors that affect soil CO2 efflux (Rs). In the agro-pastoral area of northern China, land-use types have changed considerably during the last 60 years due to changes in the social-economic status of the human population and associated changes i...

  17. Respirator field performance factors

    Skaggs, B.J.; DeField, J.D.; Strandberg, S.W.; Sutcliffe, C.R.

    1985-01-01

    The Industrial Hygiene Group assisted OSHA and the NRC in measurements of respirator performance under field conditions. They reviewed problems associated with sampling aerosols within the respirator in order to determine fit factors (FFs) or field performance factor (FPF). In addition, they designed an environmental chamber study to determine the effects of temperature and humidity on a respirator wearer

  18. Survey of loading performance of currently available types HEPA filters under in-service conditions

    Gunn, C.A.; McDonough, J.B.

    1981-01-01

    Atmospheric dust loading tests were conducted on various industrial grade High Efficiency Particulate Air Filters. The filters tested were the European Style, Super-Flow, Standard US Design, and a Super-Pak. Filters were installed on the roof of a 3-story building. Test flows were set at a media velocity of 5 FPM (1.52 meters per min) and results show that filter life varies from 8.8 to 12.7 months. In addition, tests were coucted on the European Style filter at media velocities of 5.6 and 2.6 FPM. On the filter tested at 5.6 FPM an abrupt change in life was observed at 4 months. After more than 1 year operation at a lower velocity of 2.6 FPM the pressure rise with time is still very slow

  19. Virtual screening filters for the design of type II p38 MAP kinase inhibitors: a fragment based library generation approach.

    Badrinarayan, Preethi; Sastry, G Narahari

    2012-04-01

    In this work, we introduce the development and application of a three-step scoring and filtering procedure for the design of type II p38 MAP kinase leads using allosteric fragments extracted from virtual screening hits. The design of the virtual screening filters is based on a thorough evaluation of docking methods, DFG-loop conformation, binding interactions and chemotype specificity of the 138 p38 MAP kinase inhibitors from Protein Data Bank bound to DFG-in and DFG-out conformations using Glide, GOLD and CDOCKER. A 40 ns molecular dynamics simulation with the apo, type I with DFG-in and type II with DFG-out forms was carried out to delineate the effects of structural variations on inhibitor binding. The designed docking-score and sub-structure filters were first tested on a dataset of 249 potent p38 MAP kinase inhibitors from seven diverse series and 18,842 kinase inhibitors from PDB, to gauge their capacity to discriminate between kinase and non-kinase inhibitors and likewise to selectively filter-in target-specific inhibitors. The designed filters were then applied in the virtual screening of a database of ten million (10⁷) compounds resulting in the identification of 100 hits. Based on their binding modes, 98 allosteric fragments were extracted from the hits and a fragment library was generated. New type II p38 MAP kinase leads were designed by tailoring the existing type I ATP site binders with allosteric fragments using a common urea linker. Target specific virtual screening filters can thus be easily developed for other kinases based on this strategy to retrieve target selective compounds. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Development of Shunt-Type Three-Phase Active Power Filter with Novel Adaptive Control for Wind Generators

    Ming-Hung Chen

    2015-01-01

    Full Text Available This paper proposes a new adaptive filter for wind generators that combines instantaneous reactive power compensation technology and current prediction controller, and therefore this system is characterized by low harmonic distortion, high power factor, and small DC-link voltage variations during load disturbances. The performance of the system was first simulated using MATLAB/Simulink, and the possibility of an adaptive digital low-pass filter eliminating current harmonics was confirmed in steady and transient states. Subsequently, a digital signal processor was used to implement an active power filter. The experimental results indicate, that for the rated operation of 2 kVA, the system has a total harmonic distortion of current less than 5.0% and a power factor of 1.0 on the utility side. Thus, the transient performance of the adaptive filter is superior to the traditional digital low-pass filter and is more economical because of its short computation time compared with other types of adaptive filters.

  1. Development of Shunt-Type Three-Phase Active Power Filter with Novel Adaptive Control for Wind Generators.

    Chen, Ming-Hung

    2015-01-01

    This paper proposes a new adaptive filter for wind generators that combines instantaneous reactive power compensation technology and current prediction controller, and therefore this system is characterized by low harmonic distortion, high power factor, and small DC-link voltage variations during load disturbances. The performance of the system was first simulated using MATLAB/Simulink, and the possibility of an adaptive digital low-pass filter eliminating current harmonics was confirmed in steady and transient states. Subsequently, a digital signal processor was used to implement an active power filter. The experimental results indicate, that for the rated operation of 2 kVA, the system has a total harmonic distortion of current less than 5.0% and a power factor of 1.0 on the utility side. Thus, the transient performance of the adaptive filter is superior to the traditional digital low-pass filter and is more economical because of its short computation time compared with other types of adaptive filters.

  2. Recommendations for Evaluating Multiple Filters in Ballast Water Management Systems for US Type Approval

    2016-01-01

    8 Figure 5. Slotted tube ...ISO 1990). Slotted element refers to a filter where slots are created in a tubular shape (Figure 5). Figure 5. Slotted tube (HYDAC 2014...Hospital inpatient care General surgery Bag Filters - Non supported (flexible) microfine fiberglass or synthetic media, 12 to 36 inches deep

  3. Persistence of human immunodeficiency virus type 1 subtype B DNA in dried-blood samples on FTA filter paper.

    Li, Chung-Chen; Beck, Ingrid A; Seidel, Kristy D; Frenkel, Lisa M

    2004-08-01

    The stability of human immunodeficiency virus type 1 (HIV-1) DNA in whole blood collected on filter paper (FTA Card) was evaluated. After >4 years of storage at room temperature in the dark our qualitative assay detected virus at a rate similar to that of our initial test (58 of 60, 97%; P = 0.16), suggesting long-term HIV-1 DNA stability.

  4. Use of respirators for protection of workers against airborne radioactive materials

    Revoir, W.H.

    1990-01-01

    The various types of respirators and the requirements for an effective respirator program are outlined. The use of specific types of respirators to protect workers against inhalation of airborne radioactive materials is discussed. Problems encountered in using respirators in the nuclear industry which have resulted in worker injury and death are described

  5. The application of wedge type compensation filter for uniform density on the endoscopic retrograde pancreatography

    Son, Soon Yong; Lee, Hee Jeong; Lee, Won Hong; Cho, Cheong Chan; Ryu, Meung Sun; Jung, Hong Ryang

    2001-01-01

    Over-density of pancreatic duct tail part on the endoscopic retrograde pancreatogram results from patient's position and inserted air during the study. The aim of this paper is to decide the filter angle to obtain an uniform density. Endoscopic retrograde pancratography was performed to 234 patients, and angled wedge filter was used differently. They are 10 deg (47), 20 deg (45), 30 deg (50). We also did not use wedge filter to 42 patients. We decided reliance degree in 95%. The statistical difference was p<0.05. The patients' sex rate was 1.8:1 between 18 and 87 years old(average age 58 years). Their body girth was 18.71 cm on the average. Of total 234 patients, difference of right and left average density was 0.01 by 30 deg wedge filter, -0.08 40 deg wedge filter and 0.27 non-wedge filter. These average values of difference density were very significant statistically, and standard deviation also was close to regular distribution. In conclusion, there is a usefulness of angled wedge filter for increasing diagnostic value of pancreatic duct tail part on the endoscopic retrograde pancreatogram

  6. Stability Analysis of a Matrix Converter Drive: Effects of Input Filter Type and the Voltage Fed to the Modulation Algorithm

    M. Hosseini Abardeh

    2015-03-01

    Full Text Available The matrix converter instability can cause a substantial distortion in the input currents and voltages which leads to the malfunction of the converter. This paper deals with the effects of input filter type, grid inductance, voltage fed to the modulation algorithm and the synchronous rotating digital filter time constant on the stability and performance of the matrix converter. The studies are carried out using eigenvalues of the linearized system and simulations. Two most common schemes for the input filter (LC and RLC are analyzed. It is shown that by a proper choice of voltage input to the modulation algorithm, structure of the input filter and its parameters, the need for the digital filter for ensuring the stability can be resolved. Moreover, a detailed model of the system considering the switching effects is simulated and the results are used to validate the analytical outcomes. The agreement between simulation and analytical results implies that the system performance is not deteriorated by neglecting the nonlinear switching behavior of the converter. Hence, the eigenvalue analysis of the linearized system can be a proper indicator of the system stability.

  7. Mitochondrial respiration is sensitive to cytoarchitectural breakdown.

    Kandel, Judith; Angelin, Alessia A; Wallace, Douglas C; Eckmann, David M

    2016-11-07

    An abundance of research suggests that cellular mitochondrial and cytoskeletal disruption are related, but few studies have directly investigated causative connections between the two. We previously demonstrated that inhibiting microtubule and microfilament polymerization affects mitochondrial motility on the whole-cell level in fibroblasts. Since mitochondrial motility can be indicative of mitochondrial function, we now further characterize the effects of these cytoskeletal inhibitors on mitochondrial potential, morphology and respiration. We found that although they did not reduce mitochondrial inner membrane potential, cytoskeletal toxins induced significant decreases in basal mitochondrial respiration. In some cases, basal respiration was only affected after cells were pretreated with the calcium ionophore A23187 in order to stress mitochondrial function. In most cases, mitochondrial morphology remained unaffected, but extreme microfilament depolymerization or combined intermediate doses of microtubule and microfilament toxins resulted in decreased mitochondrial lengths. Interestingly, these two particular exposures did not affect mitochondrial respiration in cells not sensitized with A23187, indicating an interplay between mitochondrial morphology and respiration. In all cases, inducing maximal respiration diminished differences between control and experimental groups, suggesting that reduced basal respiration originates as a largely elective rather than pathological symptom of cytoskeletal impairment. However, viability experiments suggest that even this type of respiration decrease may be associated with cell death.

  8. All-optical clock recovery of NRZ-DPSK signals using optical resonator-type filters

    Peucheret, Christophe; Seoane, Jorge; Ji, Hua

    2009-01-01

    It is shown how introducing a limited rise time to the driving signal enables all-optical clock recovery of NRZ-DPSK signals generated using a phase modulator. A Fabry-Perot filter is used to generate the optical clock.......It is shown how introducing a limited rise time to the driving signal enables all-optical clock recovery of NRZ-DPSK signals generated using a phase modulator. A Fabry-Perot filter is used to generate the optical clock....

  9. Exergy Analysis and Optimization of an Alpha Type Stirling Engine Using the Implicit Filtering Algorithm

    James A. Wills

    2017-12-01

    Full Text Available This paper presents the exergy analysis and optimization of the Stirling engine, which has enormous potential for use in the renewable energy industry as it is quiet, efficient, and can operate with a variety of different heat sources and, therefore, has multi-fuel capabilities. This work aims to present a method that can be used by a Stirling engine designer to quickly and efficiently find near-optimal or optimal Stirling engine geometry and operating conditions. The model applies the exergy analysis methodology to the ideal-adiabatic Stirling engine model. In the past, this analysis technique has only been applied to highly idealized Stirling cycle models and this study shows its use in the realm of Stirling cycle optimization when applied to a more complex model. The implicit filtering optimization algorithm is used to optimize the engine as it quickly and efficiently computes the optimal geometry and operating frequency that gives maximum net-work output at a fixed energy input. A numerical example of a 1,000 cm3 engine is presented, where the geometry and operating frequency of the engine are optimized for four different regenerator mesh types, varying heater inlet temperature and a fixed energy input of 15 kW. The WN200 mesh is seen to perform best of the four mesh types analyzed, giving the greatest net-work output and efficiency. The optimal values of several different engine parameters are presented in the work. It is shown that the net-work output and efficiency increase with increasing heater inlet temperature. The optimal dead-volume ratio, swept volume ratio, operating frequency, and phase angle are all shown to decrease with increasing heater inlet temperature. In terms of the heat exchanger geometry, the heater and cooler tubes are seen to decrease in size and the cooler and heater effectiveness is seen to decrease with increasing heater temperature, whereas the regenerator is seen to increase in size and effectiveness. In

  10. Sensory Pollution from Bag Filters, Carbon Filters and Combinations

    Bekö, Gabriel; Clausen, Geo; Weschler, Charles J.

    2008-01-01

    by an upstream pre-filter (changed monthly), an EU7 filter protected by an upstream activated carbon (AC) filter, and EU7 filters with an AC filter either downstream or both upstream and downstream. In addition, two types of stand-alone combination filters were evaluated: a bag-type fiberglass filter...... that contained AC and a synthetic fiber cartridge filter that contained AC. Air that had passed through used filters was most acceptable for those sets in which an AC filter was used downstream of the particle filter. Comparable air quality was achieved with the stand-alone bag filter that contained AC...

  11. Regulation of mitochondrial respiration by inorganic phosphate; comparing permeabilized muscle fibers and isolated mitochondria prepared from type-1 and type-2 rat skeletal muscle

    Scheibye-Knudsen, Morten; Quistorff, Bjørn

    2008-01-01

    ADP is generally accepted as a key regulator of oxygen consumption both in isolated mitochondria and in permeabilized fibers from skeletal muscle. The present study explored inorganic phosphate in a similar regulatory role. Saponin permeabilized fibers and isolated mitochondria from type-I and type...

  12. Conservation of Mass and Preservation of Positivity with Ensemble-Type Kalman Filter Algorithms

    Janjic, Tijana; Mclaughlin, Dennis; Cohn, Stephen E.; Verlaan, Martin

    2014-01-01

    This paper considers the incorporation of constraints to enforce physically based conservation laws in the ensemble Kalman filter. In particular, constraints are used to ensure that the ensemble members and the ensemble mean conserve mass and remain nonnegative through measurement updates. In certain situations filtering algorithms such as the ensemble Kalman filter (EnKF) and ensemble transform Kalman filter (ETKF) yield updated ensembles that conserve mass but are negative, even though the actual states must be nonnegative. In such situations if negative values are set to zero, or a log transform is introduced, the total mass will not be conserved. In this study, mass and positivity are both preserved by formulating the filter update as a set of quadratic programming problems that incorporate non-negativity constraints. Simple numerical experiments indicate that this approach can have a significant positive impact on the posterior ensemble distribution, giving results that are more physically plausible both for individual ensemble members and for the ensemble mean. In two examples, an update that includes a non-negativity constraint is able to properly describe the transport of a sharp feature (e.g., a triangle or cone). A number of implementation questions still need to be addressed, particularly the need to develop a computationally efficient quadratic programming update for large ensemble.

  13. Design and Simulation of a T-Type Lymphocyte Cells Filter on a Microfluidic System

    Daniel A. Quiroga T.

    2016-01-01

    Full Text Available This work consisted in designing and validating, by experimental computational simulation, a T-Lymphocites filtering system based on microfluidics for hiv virus detection. Material and methods: It was used AutoDesk® Inventor simulation tool was used with which the microflui­dic system design was performed. The filter system was tested by a computer simulation in the AutoDesk® Simulation cfd (computational fluid dynamics software, simulation tool in which different particles with different diameters (5 μm, 10 μm, 15 μm flow through the system to test. Results and conclusions: Results showed that this system allowed to pass the expected particles, however, it also was observed that it allows bigger particles than desired, for this reason it is neces­sary to keep on working on system perfectioning. Filtering system efficiency was of a 33.33 %.

  14. Mass Conservation and Positivity Preservation with Ensemble-type Kalman Filter Algorithms

    Janjic, Tijana; McLaughlin, Dennis B.; Cohn, Stephen E.; Verlaan, Martin

    2013-01-01

    Maintaining conservative physical laws numerically has long been recognized as being important in the development of numerical weather prediction (NWP) models. In the broader context of data assimilation, concerted efforts to maintain conservation laws numerically and to understand the significance of doing so have begun only recently. In order to enforce physically based conservation laws of total mass and positivity in the ensemble Kalman filter, we incorporate constraints to ensure that the filter ensemble members and the ensemble mean conserve mass and remain nonnegative through measurement updates. We show that the analysis steps of ensemble transform Kalman filter (ETKF) algorithm and ensemble Kalman filter algorithm (EnKF) can conserve the mass integral, but do not preserve positivity. Further, if localization is applied or if negative values are simply set to zero, then the total mass is not conserved either. In order to ensure mass conservation, a projection matrix that corrects for localization effects is constructed. In order to maintain both mass conservation and positivity preservation through the analysis step, we construct a data assimilation algorithms based on quadratic programming and ensemble Kalman filtering. Mass and positivity are both preserved by formulating the filter update as a set of quadratic programming problems that incorporate constraints. Some simple numerical experiments indicate that this approach can have a significant positive impact on the posterior ensemble distribution, giving results that are more physically plausible both for individual ensemble members and for the ensemble mean. The results show clear improvements in both analyses and forecasts, particularly in the presence of localized features. Behavior of the algorithm is also tested in presence of model error.

  15. Choosing the right respirator

    Bidwell, J.

    1997-01-01

    Selecting respirators to help protect workers from airborne contaminants can be a confusing process. The consequences of selecting the incorrect respirator can be intimidating, and worker safety and health may be dramatically and irreparably affected if an inappropriate respirator is chosen. When used in the workplace, a formal respiratory protection program must be established covering the basic requirements outlined in the OSHA Respiratory Protection Standard (29 CFR 1910.134). Education and training must be properly emphasized and conducted periodically. Maintenance, cleaning, and storage programs must be established and routinely followed for reusable respirators. The process of establishing a respiratory protection program can be broken down into four basic steps: Identify respiratory hazards and concentrations; understand the contaminants effects on workers' health; select appropriate respiratory protection; and train in proper respirator use and maintenance. These four steps are the foundation for establishing a basic respirator protection program. Be sure to consult state and federal OSHA requirements to ensure that the program complies. Leading industrial respirator manufacturers should be able to assist with on-site training and education in this four-step process, in addition to helping employers train their workers and conduct respirator fit testing

  16. Hydrodynamic calculation of a filter washing in liquids type used in containment venting systems

    Reyes G, A. A.; Sainz M, E.; Ortiz V, J.

    2015-09-01

    From the nuclear accident of Chernobyl, the European nuclear power plants have chosen to install filters on the venting pipes of the containment, whose function is to help to mitigate the consequences of a severe accident, by controlled depressurization of the containment passively through a filtered venting of the containment system. These systems are designed to relieve the internal pressure of the containment by means of the deliberate opening of pressure relief devices, either a valve or rupture disc during a severe accident and be channeled to the filter unit. In this paper the hydraulic response of a filter system of gases washing by liquid is evaluated, due to this information is necessary to estimate the effect that has the pressure increase of the contention on the discharge capacity of the venting pipes. By simulation of computational of fluid dynamics with the programs: CAELINUX-2014 and OpenFOAM, the hydrodynamic characteristics of the Multi Venturi System for gases washing from the containment, which could be included in the general model of the venting pipe, were obtained. Representative models of the Venturi tubes of each concentric area that forming the washing system were generated; and using parametric calculations the average mass flow rate established through each venturi, depending on its size and depth in which it is located inside the tank was estimated. Also, the pressure and mass flow rate required to activate each concentric area depending on the pressure and mass load from the containment were calculated, to estimate the maximum flow that is established through the filter. Finally, the velocity profiles and the characteristic pressure at which each area operates as well as the pressure drop of local and global discharge also were calculated. (Author)

  17. Hybrid Multi-objective Forecasting of Solar Photovoltaic Output Using Kalman Filter based Interval Type-2 Fuzzy Logic System

    Hassan, Saima; Ahmadieh Khanesar, Mojtaba; Hajizadeh, Amin

    2017-01-01

    Learning of fuzzy parameters for system modeling using evolutionary algorithms is an interesting topic. In this paper, two optimal design and tuning of Interval type-2 fuzzy logic system are proposed using hybrid learning algorithms. The consequent parameters of the interval type-2 fuzzy logic...... system in both the hybrid algorithms are tuned using Kalman filter. Whereas the antecedent parameters of the system in the first hybrid algorithm is optimized using the multi-objective particle swarm optimization (MOPSO) and using the multi-objective evolutionary algorithm Based on Decomposition (MOEA...

  18. Soil Respiration And Respiration Partitioning In An Oak-Savannah With A History Of Fertilization

    Morris, K. A.; Nair, R.; Schrumpf, M.; Migliavacca, M.

    2017-12-01

    Soil respiration is a combination of autotrophic and heterotrophic components. These components have different controls and structurally complex ecosystems such as oak-savannahs offer an opportunity to study strongly contrasting conditions (ie., soil from under trees versus open areas) in an environment with similar soil mineralogy and climatic patterns. To measure respiration coming from plant roots, fungal hyphae, and free-living microbes we established stations of soil cores comprised of three selectively permeable meshes under tree canopies and in open grassy areas of a Holm Oak (Quercus ilex) savannah in Extremadura, Spain. Large plots of this ecosystem had previously been fertilized as part of a stoichiometeric imbalance study (in 2015). Stations were installed in Dec. 2016 within four plots; control, N added, P added, and N+P added. Respiration from cores was measured in campaigns at key phenological stages with a portable Li-Cor 8100A unit. Six months after installation > 50% of soil respiration was attributable to free-living microbes. There is a persistent effect of the prior fertilization, resulting in increased soil respiration in open areas regardless of fertilizer type, while respiration from under tree canopies had a varied response. Soil under tree canopies showed distinct sensitivity to stoichiometric imbalance, meaning that addition of N or P alone either did not change respiration or decreased it slightly, while N+P stimulated respiration. We determined that respiration from free-living microbes is a major component of soil respiration even in the most active plant growing season. However, because of the lag between the time of fertilization and the time of measurement, it not possible to say whether treatment responses are due solely to nutrient status of the soil or whether changes in plant biomass and species composition also play a role. Additional work planned at the site will shed light on this uncertainty as well as the contribution of

  19. FDTD parallel computational analysis of grid-type scattering filter characteristics for medical X-ray image diagnosis

    Takahashi, Koichi; Miyazaki, Yasumitsu; Goto, Nobuo

    2007-01-01

    X-ray diagnosis depends on the intensity of transmitted and scattered waves in X-ray propagation in biomedical media. X-ray is scattered and absorbed by tissues, such as fat, bone and internal organs. However, image processing for medical diagnosis, based on the scattering and absorption characteristics of these tissues in X-ray spectrum is not so much studied. To obtain precise information of tissues in a living body, the accurate characteristics of scattering and absorption are required. In this paper, X-ray scattering and absorption in biomedical media are studied using 2-dimensional finite difference time domain (FDTD) method. In FDTD method, the size of analysis space is very limited by the performance of available computers. To overcome this limitation, parallel and successive FDTD method is introduced. As a result of computer simulation, the amplitude of transmitted and scattered waves are presented numerically. The fundamental filtering characteristics of grid-type filter are also shown numerically. (author)

  20. Respiration in Aquatic Insects.

    MacFarland, John

    1985-01-01

    This article: (1) explains the respiratory patterns of several freshwater insects; (2) describes the differences and mechanisms of spiracular cutaneous, and gill respiration; and (3) discusses behavioral aspects of selected aquatic insects. (ML)

  1. Respiration in spiders (Araneae).

    Schmitz, Anke

    2016-05-01

    Spiders (Araneae) are unique regarding their respiratory system: they are the only animal group that breathe simultaneously with lungs and tracheae. Looking at the physiology of respiration the existence of tracheae plays an important role in spiders with a well-developed tracheal system. Other factors as sex, life time, type of prey capture and the high ability to gain energy anaerobically influence the resting and the active metabolic rate intensely. Most spiders have metabolic rates that are much lower than expected from body mass; but especially those with two pairs of lungs. Males normally have higher resting rates than females; spiders that are less evolved and possess a cribellum have lower metabolic rates than higher evolved species. Freely hunting spiders show a higher energy turnover than spiders hunting with a web. Spiders that live longer than 1 year will have lower metabolic rates than those species that die after 1 year in which development and reproduction must be completed. Lower temperatures and starvation, which most spiders can cope with, will decrease the metabolic rate as well.

  2. Respirator studies for the Nuclear Regulatory Commission (NRC)

    Skaggs, B.J.; Fairchild, C.I.; DeField, J.D.; Hack, A.L.

    1985-01-01

    A project of the Health, Safety and Environment Division is described. The project provides the NRC with information of respiratory protective devices and programs for their licensee personnel. The following activities were performed during FY 1983: selection of alternate test aerosols for quality assurance testing of high-efficiency particulate air respirator filters; evaluation of MAG-1 spectacles for use with positive and negative-pressure respirators; development of a Manual of Respiratory Protection in Emergencies Involving Airborne Radioactive Materials, and technical assistance to NRC licensees regarding respirator applications. 2 references, 1 figure

  3. Pollution patterns and underlying relationships of benzophenone-type UV-filters in wastewater treatment plants and their receiving surface water.

    Wu, Ming-Hong; Li, Jian; Xu, Gang; Ma, Luo-Dan; Li, Jia-Jun; Li, Jin-Song; Tang, Liang

    2018-05-15

    The environmental behaviors of emerging pollutants, benzophenone-type UV filters (BP-UV filters) and their derivatives were investigated in four wastewater treatment plants (WWTPs), and their receiving surface waters in Shanghai. The concentration level of selected BP-UV filters in the WWTPs was detected from ngL -1 to μgL -1 . BP (621-951ngL -1 ) and BP-3 (841-1.32 × 10 3 ngL -1 ) were the most abundant and highest detection frequency individuals among the target BP-UV filters in influents, whereas BP (198-400ngL -1 ), BP-4 (93.3-288ngL -1 ) and BP-3 (146-258ngL -1 ) were predominant in effluents. BP-UV filters cannot be completely removed and the total removal efficiency varied widely (-456% to 100%) during the treatment process. It can be inferred that the usage of BP and BP-3 are higher than other BP-UV filters in the study area. The lowest and highest levels were BP-2 (ND-7.66ngL -1 ) and BP-3 (68.5-5.01 × 10 3 ng L -1 ) in the receiving surface water, respectively. Interestingly, the seasonal variation of BP-3 is larger than those of other BP-UV filters in surface water from Shanghai. There is no obvious pollution pattern of BP-UV filters in the surface water from the cosmetic factory area. The correlation analysis of BP-UV filters between WWTPs effluents and nearby downstream water samples suggested that BP-UV filters emitted from some WWTPs might be the main source of receiving surface water. Preliminary risk assessment indicated that the levels of BP-UV filters detected by the effluent posed medium to high risk to fish as well as other aquatic organisms. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. An inkjet printed stripe-type color filter of liquid crystal display

    Chen, Chin-Tai; Wu, Kuo-Hua; Shieh, Fanny; Lu, Chun-Fu

    2010-01-01

    In this paper, we propose a comprehensive concept and new design of a drop-on-demand (DOD) inkjet printing process for fabricating color filter (CF) layers of liquid crystal displays (LCDs) onto the structured surfaces of flat substrates, composed of 'physical sidewalls' for aligning and controlling the liquid morphology. Several fundamental guidelines of the design have been addressed in current inkjet-printing techniques. Using a droplet generator (printhead) of the deposition system, the color-ink drops can be jetted and placed over the specific domains, where the sidewalls align the flow merged from a stream of droplets and fulfill the coverage of the defined areas, in which the geometrical relations correlating the droplets and sidewalls are explicitly expressed in the study. According to the results of the simulation and analysis, the proposed sidewalls, acting as the physical barriers, can control the liquid morphology through the simple geometric factors such as sidewall widths, heights and contact angles. The experimental results showed that the solid RGB color layers were self-assembled from the liquid droplets and formed with the uniform thickness, except for the neighborhood of the sidewalls. It indicated that the sidewalls serving as 'physical barriers' had a remarkable effect in confining and self-aligning the droplet flow within the desirable regions. This inkjet-printing method would alternatively offer one cost-effective and high-flexibility method for the production of the versatile LCD CF, thus being particularly beneficial for large-area printing and flexible substrates.

  5. Metabolic interactions between methanogenic consortia and anaerobic respiring bacteria

    Stams, A.J.; Oude Elferink, S.J.; Westermann, Peter

    2003-01-01

    Most types of anaerobic respiration are able to outcompete methanogenic consortia for common substrates if the respective electron acceptors are present in sufficient amounts. Furthermore, several products or intermediate compounds formed by anaerobic respiring bacteria are toxic to methanogenic...... consortia. Despite the potentially adverse effects, only few inorganic electron acceptors potentially utilizable for anaerobic respiration have been investigated with respect to negative interactions in anaerobic digesters. In this chapter we review competitive and inhibitory interactions between anaerobic...... respiring populations and methanogenic consortia in bioreactors. Due to the few studies in anaerobic digesters, many of our discussions are based upon studies of defined cultures or natural ecosystems...

  6. Laboratory for filter testing

    Paluch, W.

    1987-07-01

    Filters used for mine draining in brown coal surface mines are tested by the Mine Draining Department of Poltegor. Laboratory tests of new types of filters developed by Poltegor are analyzed. Two types of tests are used: tests of scale filter models and tests of experimental units of new filters. Design and operation of the test stands used for testing mechanical properties and hydraulic properties of filters for coal mines are described: dimensions, pressure fluctuations, hydraulic equipment. Examples of testing large-diameter filters for brown coal mines are discussed.

  7. Effect of application rates and media types on nitrogen and surfactant removal in trickling filters applied to the post-treatment of effluents from UASB reactors

    Almeida, P. G. S. de; Taveres, F. v. F.; Chernicharo, C. A. I.

    2009-07-01

    Tricking filters are a very promising alternative for the post treatment of effluents from UASB reactors treating domestic sewage,especially in developing countries. Although a fair amount of information is already available regarding organic mater removal in this combined system, very little is known in relation to nitrogen and surfactant removal in trickling filters post-UASB reactors. Therefore, the purpose of this study was to evaluate and compare the effect evaluate and compare the effect of different application rates and packing media types on trickling filters applied to the post-treatment of effluents from UASB reactors, regarding the removal of ammonia nitrogen and surfactants. (Author)

  8. Effect of application rates and media types on nitrogen and surfactant removal in trickling filters applied to the post-treatment of effluents from UASB reactors

    Almeida, P. G. S. de; Taveres, F. v. F.; Chernicharo, C. A. I.

    2009-01-01

    Tricking filters are a very promising alternative for the post treatment of effluents from UASB reactors treating domestic sewage,especially in developing countries. Although a fair amount of information is already available regarding organic mater removal in this combined system, very little is known in relation to nitrogen and surfactant removal in trickling filters post-UASB reactors. Therefore, the purpose of this study was to evaluate and compare the effect evaluate and compare the effect of different application rates and packing media types on trickling filters applied to the post-treatment of effluents from UASB reactors, regarding the removal of ammonia nitrogen and surfactants. (Author)

  9. A graph signal filtering-based approach for detection of different edge types on airborne lidar data

    Bayram, Eda; Vural, Elif; Alatan, Aydin

    2017-10-01

    Airborne Laser Scanning is a well-known remote sensing technology, which provides a dense and highly accurate, yet unorganized point cloud of earth surface. During the last decade, extracting information from the data generated by airborne LiDAR systems has been addressed by many studies in geo-spatial analysis and urban monitoring applications. However, the processing of LiDAR point clouds is challenging due to their irregular structure and 3D geometry. In this study, we propose a novel framework for the detection of the boundaries of an object or scene captured by LiDAR. Our approach is motivated by edge detection techniques in vision research and it is established on graph signal filtering which is an exciting and promising field of signal processing for irregular data types. Due to the convenient applicability of graph signal processing tools on unstructured point clouds, we achieve the detection of the edge points directly on 3D data by using a graph representation that is constructed exclusively to answer the requirements of the application. Moreover, considering the elevation data as the (graph) signal, we leverage aerial characteristic of the airborne LiDAR data. The proposed method can be employed both for discovering the jump edges on a segmentation problem and for exploring the crease edges on a LiDAR object on a reconstruction/modeling problem, by only adjusting the filter characteristics.

  10. Land-use type and intensity differentially filter traits in above- and below-ground arthropod communities.

    Birkhofer, Klaus; Gossner, Martin M; Diekötter, Tim; Drees, Claudia; Ferlian, Olga; Maraun, Mark; Scheu, Stefan; Weisser, Wolfgang W; Wolters, Volkmar; Wurst, Susanne; Zaitsev, Andrey S; Smith, Henrik G

    2017-05-01

    Along with the global decline of species richness goes a loss of ecological traits. Associated biotic homogenization of animal communities and narrowing of trait diversity threaten ecosystem functioning and human well-being. High management intensity is regarded as an important ecological filter, eliminating species that lack suitable adaptations. Below-ground arthropods are assumed to be less sensitive to such effects than above-ground arthropods. Here, we compared the impact of management intensity between (grassland vs. forest) and within land-use types (local management intensity) on the trait diversity and composition in below- and above-ground arthropod communities. We used data on 722 arthropod species living above-ground (Auchenorrhyncha and Heteroptera), primarily in soil (Chilopoda and Oribatida) or at the interface (Araneae and Carabidae). Our results show that trait diversity of arthropod communities is not primarily reduced by intense local land use, but is rather affected by differences between land-use types. Communities of Auchenorrhyncha and Chilopoda had significantly lower trait diversity in grassland habitats as compared to forests. Carabidae showed the opposite pattern with higher trait diversity in grasslands. Grasslands had a lower proportion of large Auchenorrhyncha and Carabidae individuals, whereas Chilopoda and Heteroptera individuals were larger in grasslands. Body size decreased with land-use intensity across taxa, but only in grasslands. The proportion of individuals with low mobility declined with land-use intensity in Araneae and Auchenorrhyncha, but increased in Chilopoda and grassland Heteroptera. The proportion of carnivorous individuals increased with land-use intensity in Heteroptera in forests and in Oribatida and Carabidae in grasslands. Our results suggest that gradients in management intensity across land-use types will not generally reduce trait diversity in multiple taxa, but will exert strong trait filtering within

  11. Laboratory evaluation of the particle size effect on the performance of an elastomeric half-mask respirator against ultrafine combustion particles.

    He, Xinjian; Grinshpun, Sergey A; Reponen, Tiina; Yermakov, Michael; McKay, Roy; Haruta, Hiroki; Kimura, Kazushi

    2013-08-01

    This study quantified the particle size effect on the performance of elastomeric half-mask respirators, which are widely used by firefighters and first responders exposed to combustion aerosols. One type of elastomeric half-mask respirator equipped with two P-100 filters was donned on a breathing manikin while challenged with three combustion aerosols (originated by burning wood, paper, and plastic). Testing was conducted with respirators that were fully sealed, partially sealed (nose area only), or unsealed to the face of a breathing manikin to simulate different faceseal leakages. Three cyclic flows with mean inspiratory flow (MIF) rates of 30, 85, and 135 L/min were tested for each combination of sealing condition and combustion material. Additional testing was performed with plastic combustion particles at other cyclic and constant flows. Particle penetration was determined by measuring particle number concentrations inside and outside the respirator with size ranges from 20 to 200 nm. Breathing flow rate, particle size, and combustion material all had significant effects on the performance of the respirator. For the partially sealed and unsealed respirators, the penetration through the faceseal leakage reached maximum at particle sizes >100 nm when challenged with plastic aerosol, whereas no clear peaks were observed for wood and paper aerosols. The particles aerosolized by burning plastic penetrated more readily into the unsealed half-mask than those aerosolized by the combustion of wood and paper. The difference may be attributed to the fact that plastic combustion particles differ from wood and paper particles by physical characteristics such as charge, shape, and density. For the partially sealed respirator, the highest penetration values were obtained at MIF = 85 L/min. The unsealed respirator had approximately 10-fold greater penetration than the one partially sealed around the bridge of the nose, which indicates that the nose area was the primary leak

  12. Test equipment used for radiation protection type testing of aerosol filters at the National Board of Nuclear Safety and Radiation Protection (SAAS)

    Ullmann, W.; Przyborowski, S.

    1977-01-01

    Following a description of the overall design of test equipment developed in the SAAS for radiation protection type testing of aerosol filters, the most important physical and technical details concerning the preparation and measurement of test aerosols as well as the sampling procedure upstream and downstream of the filter to the tested, are comprehensively discussed. Furthermore, experiences gained during several years with different devices for mixing and diluting the aerosols are reported. (author)

  13. Cattle respiration facility

    Hellwing, Anne Louise Frydendahl; Lund, Peter; Weisbjerg, Martin Riis

    2012-01-01

    In Denmark, the emission rate of methane from dairy cows has been calculated using the IPCC standard values for dairy cows in Western countries, due to the lack of national data. Therefore, four respiration chambers for dairy cows were built with the main purpose of measuring methane, but also...

  14. Plant Respiration and Climate Change Effects

    Bruhn, D.

    2002-04-01

    Plant respiration is one of the key processes in terms of an understanding of plant growth and functioning in a future climate. Short- and long-term effects of temperature and CO 2 on plant respiration were investigated in a number of plant species. The experiments tested effects of either temperature and/or CO 2 from the level of individual respiratory enzymes, isolated mitochondria, whole-tissue, and up to the whole canopy level. The short-term effects of elevated atmospheric CO 2 on plant respiration appeared to be less than suggested so far in the literature. This was true both at the tissue level and for intact mitochondria. Respiratory enzymes can, however, be affected already at low CO 2 . These effects did not manifest itself at the tissue level, though, due to low degrees of control on the whole respiratory process exerted by the particular enzymes. Plant respiration on the other hand was affected by long-term growth at elevated atmospheric CO 2 . The findings of the reduced plant respiration at the leaf level were consistent with the literature and potential causes are discussed. Short-term effects of temperature on plant respiration were demonstrated to be dependent on the actual measurement temperature. Further, it is shown that mitochondrial leaf respiration in darkness and light differ substantially in the temperature sensitivity with the former being the far most sensitive. This has implications for modelling CO 2 exchange between vegetation and atmosphere as demonstrated here, since this has so far been neglected. Long-term effects of temperature resulted in respiratory acclimation in a number of species. Respiratory acclimation appeared not to occur to any one single type of growth temperature. The implications of this finding in combination with the timing of acclimation are discussed for modelling respiratory CO 2 release. (au)

  15. Plant Respiration and Climate Change Effects

    Bruhn, D

    2002-04-01

    Plant respiration is one of the key processes in terms of an understanding of plant growth and functioning in a future climate. Short- and long-term effects of temperature and CO{sub 2} on plant respiration were investigated in a number of plant species. The experiments tested effects of either temperature and/or CO{sub 2} from the level of individual respiratory enzymes, isolated mitochondria, whole-tissue, and up to the whole canopy level. The short-term effects of elevated atmospheric CO{sub 2} on plant respiration appeared to be less than suggested so far in the literature. This was true both at the tissue level and for intact mitochondria. Respiratory enzymes can, however, be affected already at low CO{sub 2}. These effects did not manifest itself at the tissue level, though, due to low degrees of control on the whole respiratory process exerted by the particular enzymes. Plant respiration on the other hand was affected by long-term growth at elevated atmospheric CO{sub 2}. The findings of the reduced plant respiration at the leaf level were consistent with the literature and potential causes are discussed. Short-term effects of temperature on plant respiration were demonstrated to be dependent on the actual measurement temperature. Further, it is shown that mitochondrial leaf respiration in darkness and light differ substantially in the temperature sensitivity with the former being the far most sensitive. This has implications for modelling CO{sub 2} exchange between vegetation and atmosphere as demonstrated here, since this has so far been neglected. Long-term effects of temperature resulted in respiratory acclimation in a number of species. Respiratory acclimation appeared not to occur to any one single type of growth temperature. The implications of this finding in combination with the timing of acclimation are discussed for modelling respiratory CO{sub 2} release. (au)

  16. Mathias-Prikry and Laver type forcing; Summable ideals, coideals, and +-selective filters

    Chodounský, David; Guzmán Gonzáles, O.; Hrušák, M.

    2016-01-01

    Roč. 55, č. 3 (2016), s. 493-504 ISSN 0933-5846 R&D Projects: GA ČR(CZ) GF15-34700L Institutional support: RVO:67985840 Keywords : Mathias–Prikry forcing * Laver type forcing * Mathias like real Subject RIV: BA - General Mathematics Impact factor: 0.394, year: 2016 http://link.springer.com/article/10.1007/s00153-016-0476-9

  17. The Effects of Two Types of Sleep Deprivation on Visual Working Memory Capacity and Filtering Efficiency

    Drummond, Sean P. A.; Anderson, Dane E.; Straus, Laura D.; Vogel, Edward K.; Perez, Veronica B.

    2012-01-01

    Sleep deprivation has adverse consequences for a variety of cognitive functions. The exact effects of sleep deprivation, though, are dependent upon the cognitive process examined. Within working memory, for example, some component processes are more vulnerable to sleep deprivation than others. Additionally, the differential impacts on cognition of different types of sleep deprivation have not been well studied. The aim of this study was to examine the effects of one night of total sleep depri...

  18. Soil Respiration under Different Land Uses in Eastern China

    Fan, Li-Chao; Yang, Ming-Zhen; Han, Wen-Yan

    2015-01-01

    Land-use change has a crucial influence on soil respiration, which further affects soil nutrient availability and carbon stock. We monitored soil respiration rates under different land-use types (tea gardens with three production levels, adjacent woodland, and a vegetable field) in Eastern China at weekly intervals over a year using the dynamic closed chamber method. The relationship between soil respiration and environmental factors was also evaluated. The soil respiration rate exhibited a remarkable single peak that was highest in July/August and lowest in January. The annual cumulative respiration flux increased by 25.6% and 20.9% in the tea garden with high production (HP) and the vegetable field (VF), respectively, relative to woodland (WL). However, no significant differences were observed between tea gardens with medium production (MP), low production (LP), WL, and VF. Soil respiration rates were significantly and positively correlated with organic carbon, total nitrogen, and available phosphorous content. Each site displayed a significant exponential relationship between soil respiration and soil temperature measured at 5 cm depth, which explained 84–98% of the variation in soil respiration. The model with a combination of soil temperature and moisture was better at predicting the temporal variation of soil respiration rate than the single temperature model for all sites. Q10 was 2.40, 2.00, and 1.86–1.98 for VF, WL, and tea gardens, respectively, indicating that converting WL to VF increased and converting to tea gardens decreased the sensitivity of soil respiration to temperature. The equation of the multiple linear regression showed that identical factors, including soil organic carbon (SOC), soil water content (SWC), pH, and water soluble aluminum (WSAl), drove the changes in soil respiration and Q10 after conversion of land use. Temporal variations of soil respiration were mainly controlled by soil temperature, whereas spatial variations were

  19. Comparison of performance of three different types of respiratory protection devices.

    Lawrence, Robert B; Duling, Matthew G; Calvert, Catherine A; Coffey, Christopher C

    2006-09-01

    Respiratory protection is offered to American workers in a variety of ways to guard against potential inhalation hazards. Two of the most common ways are elastomeric N95 respirators and N95 filtering-facepiece respirators. Some in the health care industry feel that surgical masks provide an acceptable level of protection in certain situations against particular hazards. This study compared the performance of these types of respiratory protection during a simulated workplace test that measured both filter penetration and face-seal leakage. A panel of 25 test subjects with varying face sizes tested 15 models of elastomeric N95 respirators, 15 models of N95 filtering-facepiece respirators, and 6 models of surgical masks. Simulated workplace testing was conducted using a TSI PORTACOUNT Plus model 8020, and consisted of a series of seven exercises. Six simulated workplace tests were performed with redonning of the respirator/mask occurring between each test. The results of these tests produced a simulated workplace protection factor (SWPF). The geometric mean (GM) and the 5th percentile values of the SWPFs were computed by category of respiratory protection using the six overall SWPF values. The level of protection provided by each of the three respiratory protection types was compared. The GM and 5th percentile SWPF values without fit testing were used for the comparison, as surgical masks were not intended to be fit tested. The GM values were 36 for elastomeric N95 respirators, 21 for N95 filtering-facepiece respirators, and 3 for surgical masks. An analysis of variance demonstrated a statistically significant difference between all three. Elastomeric N95 respirators had the highest 5th percentile SWPF of 7. N95 filtering-facepiece respirators and surgical masks had 5th percentile SWPFs of 3 and 1, respectively. A Fisher Exact Test revealed that the 5th percentile SWPFs for all three types of respiratory protection were statistically different. In addition, both

  20. Respirators. Does your face fit

    Caro, N M; Else, D

    1981-04-01

    The authors carried out a survey of face sizes of men and women of four different ethnic origins and carried out face-seal leakage trials on four corresponding test panels. No single respirator design is likely to fit all members of the workforce, and it may be necessary to stock respirators from more than one manufacturers.Three or four different respirators or size of respirator may be needed. However, the use of lossely-fitting respirators such as Airsteam helmets could remove the necessity for exhaustive fitting procedures.

  1. Characterization of n and p-type ZnO thin films grown by pulsed filtered cathodic vacuum arc system

    Kavak, H.; Erdogan, E.N.; Ozsahin, I.; Esen, R.

    2010-01-01

    Full text : Semiconductor ZnO thin films with wide band gap attract much interest due to their properties such as chemical stability in hydrogen plasma, high optical transparency in the visible and nearinfrared region. Due to these properties ZnO oxide is a promising materials for electronic or optoelectronic applications such as solar cell (as an antireflecting coating and a transparent conducting material), gas sensors, surface acoustic wave devices. The purpose of this research is to improve the properties of n and p-type ZnO thin films for device applications. Polycrystalline ZnO is naturally n-type and very difficult to dope to make p-type. Therefore nowadays hardly produced p-type ZnO attracts a lot of attention. Nitrogen considered as the best dopant for p-type ZnO thin films.The transparent, conductive and very precise thickness controlled n and p-type semiconducting nanocrystalline ZnO thin films were prepared by pulsed filtered cathodic vacuum arc deposition (PFCVAD) method. Structural, optical and electrical properties of these films were investigated. And also photoluminescence properties of these films were investigated. Transparent p-type ZnO thin films were produced by oxidation of PFCVAD deposited zinc nitride. Zinc nitride thin films were deposited with various thicknesses and under different oxygen pressures on glass substrates. Zinc nitride thin films, which were deposited at room temperatures, were amorphous and the optical transmission was below 70%. For oxidation zinc nitride, the sample was annealed in air starting from 350 degrees Celsium up to 550 degrees Celsium for one hour duration. These XRD patterns imply that zinc nitride thin films converted to zinc oxide thin films with the same hexagonal crystalline structures of ZnO. The optical measurements were made for each annealing temperature and the optical transmissions of ZnO thin films were found better than 90 percent in visible range after annealing over 350 degrees Celsium. By

  2. Characterization of Rock Types at Meridiani Planum, Mars using MER 13-Filter Pancam Spectra

    Nuding, D. L.; Cohen, B. A.

    2009-01-01

    The Mars Exploration Rover Opportunity has traversed more than 13 km across Meridiani Planum, finding evidence of ancient aqueous environments that, in the past, may have been suitable for life. Meridiani bedrock along the rover traverse is a mixture in composition and bulk mineralogy between a sulfate-rich sedimentary rock and hematite spherules ("blueberries"). On top of the bedrock, numerous loose rocks exist. These rocks consist of both local bedrock and "cobbles" of foreign origin. The cobbles provide a window into lithologic diversity and a chance to understand other types of martian rocks and meteorites. This study was also an attempt to establish a method to expand upon those of Mini-TES to remotely identify rocks of interest to make efficient use of the rover s current resources.

  3. A Bolus Calculator Based on Continuous-Discrete Unscented Kalman Filtering for Type 1 Diabetics

    Boiroux, Dimitri; Aradóttir, Tinna Björk; Hagdrup, Morten

    2015-01-01

    both reduces the risk of hypoglycemia in case of an overestimated meal and the time spent in hyperglycemia if the meal size is underestimated. Faster insulin and the use of glucagon will have the potential to encourage postprandial meal bolus administration and hence will not require to accurately......In patients with type 1 diabetes, the effects of meals intake on blood glucose level are usually mitigated by administering a large amount of insulin (bolus) at mealtime or even slightly before. This strategy assumes, among other things, a prior knowledge of the meal size and the postprandial...... glucose dynamics. On the other hand, administering the meal bolus during or after mealtime could benefit from the information provided by the postprandial meal dynamics at the expense of a delayed meal bolus. The present paper investigates different bolus administration strategies (at mealtime, 15 minutes...

  4. Improved crud iron removal efficiency for powder resin type condensate filters

    Nagai, Hiroshi; Ino, Takao

    1989-01-01

    In 1984, a precoat type condensate filtration system was delivered to The Tokyo Electric Power Co., Inc. by Ebara and stable operation of the system is reported ever since. Originally, condensate filtration systems are used to remove crud iron in condensate water. However, it has become desirable to freely control the crud iron in the outlet flow of such filtration system. The main source of radioactivity in a BWR plant, is Cobalt 60, and it is necessary to optimally control the amount of crud iron released into the reactor to match the nickel and cobalt amounts in the reactor feed water for achieving an overall reduction of the concentration of radioactivity within the BWR plant. The method of such control, developed by the authors, is outlined in the following. By this method, the radioactive level within the overall plant is significantly decreased. Consequently, the risk of radioactive exposure of personnel at time of periodical checkup is greatly reduced. (author)

  5. Migration of Parabens, Bisphenols, Benzophenone-Type UV Filters, Triclosan, and Triclocarban from Teethers and Its Implications for Infant Exposure.

    Asimakopoulos, Alexandros G; Elangovan, Madhavan; Kannan, Kurunthachalam

    2016-12-20

    Parabens (p-hydroxybenzoic acid esters), bisphenols, benzophenone-type UV filters, triclosan, and triclocarban are used in a variety of consumer products, including baby teethers. Nevertheless, the exposure of infants to these chemicals through the use of teethers is still unknown. In this study, 59 teethers, encompassing three types, namely solid plastic, gel-filled, and water-filled (most labeled "bisphenol A-free"), were collected from the U.S. market and analyzed for 26 potential endocrine-disrupting chemicals (EDCs) from intact surfaces through migration/leaching tests performed with Milli-Q water and methanol. The total amount of the sum of six parent parabens (Σ 6 Parabens) leached from teethers ranged from 2.0 to 1990 ng, whereas that of their four transformation products (Σ 4 Parabens) ranged from 0.47 to 839 ng. The total amount of the sum of nine bisphenols (Σ 9 bisphenols) and 5 benzophenones (Σ 5 benzophenones) leached from teethers ranged from 1.93 to 213 ng and 0.59 to 297 ng, respectively. Triclosan and triclocarban were found in the extracts of teethers at approximately 10-fold less amounts than were bisphenols and benzophenones. Based on the amount leached into Milli-Q water, daily intake of these chemicals was estimated from the use of teethers by infants at 12 months of age. This is the first study to document the occurrence and migration of a wide range EDCs from intact surfaces of baby teethers.

  6. Polarization filtering in the visible wavelength range using surface plasmon resonance and a sunflower-type photonic quasi-crystal fiber

    Yan, Bei; Wang, Anran; Liu, Exian; Tan, Wei; Xie, Jianlan; Ge, Rui; Liu, Jianjun

    2018-04-01

    A novel polarization filter based on a sunflower-type photonic quasi-crystal fiber (PQF) is proposed in this paper. We also discuss different methods to tune the filter wavelength. The proposed filter can efficiently produce polarized light with visible wavelengths by using the resonance between the second-order surface plasmon polariton mode and the core mode of the PQF. The filtered wavelength can be tuned between 0.55 µm and 0.68 µm by adjusting the thickness of the gold film. When the thickness of the gold film is 25.3 nm, the resonance loss in the y-polarized direction reaches 11707 dB m‑1 for a wavelength of 0.6326 µm, and the full width at half maximum is only 5 nm. Due to the flexible design and absence of both polarization coupling and polarization dispersion, this polarization filter can be used in devices that require narrow-band filtering.

  7. Respirable dust and respirable silica exposure in Ontario gold mines.

    Verma, Dave K; Rajhans, Gyan S; Malik, Om P; des Tombe, Karen

    2014-01-01

    A comprehensive survey of respirable dust and respirable silica in Ontario gold mines was conducted by the Ontario Ministry of Labor during 1978-1979. The aim was to assess the feasibility of introducing gravimetric sampling to replace the assessment method which used konimeters, a device which gave results in terms of number of particles per cubic centimeter (ppcc) of air. The study involved both laboratory and field assessments. The field assessment involved measurement of airborne respirable dust and respirable silica at all eight operating gold mines of the time. This article describes the details of the field assessment. A total of 288 long-term (7-8 hr) personal respirable dust air samples were collected from seven occupational categories in eight gold mines. The respirable silica (α-quartz) was determined by x-ray diffraction method. The results show that during 1978-1979, the industry wide mean respirable dust was about 1 mg/m(3), and the mean respirable silica was 0.08 mg/m(3.)The mean% silica in respirable dust was 7.5%. The data set would be useful in future epidemiological and health studies, as well as in assessment of workers' compensation claims for occupational diseases such as silicosis, chronic obstructive pulmonary disease (COPD), and autoimmune diseases such as renal disease and rheumatoid arthritis.

  8. respiration and transpiration characteristics of selected fresh fruits

    AISA

    were higher in optimal atmospheres. The Q10 values ... High respiration rates increase tissue aging and decrease the ability of the product to repel ... Two types of containers were used for the ..... availability of oxygen around the product also.

  9. Respirable dust measured downwind during rock dust application.

    Harris, M L; Organiscak, J; Klima, S; Perera, I E

    2017-05-01

    The Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health (NIOSH) conducted underground evaluations in an attempt to quantify respirable rock dust generation when using untreated rock dust and rock dust treated with an anticaking additive. Using personal dust monitors, these evaluations measured respirable rock dust levels arising from a flinger-type application of rock dust on rib and roof surfaces. Rock dust with a majority of the respirable component removed was also applied in NIOSH's Bruceton Experimental Mine using a bantam duster. The respirable dust measurements obtained downwind from both of these tests are presented and discussed. This testing did not measure miners' exposure to respirable coal mine dust under acceptable mining practices, but indicates the need for effective continuous administrative controls to be exercised when rock dusting to minimize the measured amount of rock dust in the sampling device.

  10. Improvement of ballistocardiogram processing by inclusion of respiration information

    Tavakolian, Kouhyar; Vaseghi, Ali; Kaminska, Bozena

    2008-01-01

    In this paper a novel methodology for processing of a ballistocardiogram (BCG) is proposed in which the respiration signal is utilized to improve the averaging of the BCG signal and ultimately the annotation and interpretation of the signal. Previous research works filtered out the respiration signal while the novelty of the current research is that, rather than removing the respiration effect from the signal, we utilize the respiration information to improve the averaging and thus analysis and interpretation of the BCG signal in diagnosis of cardiac malfunctions. This methodology is based on our investigation that BCG cycles corresponding to the inspiration and expiration phases of the respiration cycle are different in morphology. BCG cycles corresponding to the expiration phase of respiration have been proved to be more closely related to each other when compared to cycles corresponding to inspiration, and therefore expiration cycles are better candidates to be selected for the calculation of the averaged BCG signal. The new BCG average calculated based on this methodology is then considered as the representative and a template of the BCG signal for further processing. This template can be considered as the output of a clinical BCG instrument with higher reliability and accuracy compared to the previous processing methods

  11. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT - PHYSICAL REMOVAL OF MICROBIOLOGICAL AND PARTICULATE CONTAMINANTS IN DRINKING WATER : SEPARMATIC™ FLUID SYSTEMS DIATOMACEOUS EARTH PRESSURE TYPE FILTER SYSTEM MODEL 12P-2

    The verification test of the SeparmaticTM DE Pressure Type Filter System Model 12P-2 was conducted at the UNH Water Treatment Technology Assistance Center (WTTAC) in Durham, New Hampshire. The source water was finished water from the Arthur Rollins Treatment Plant that was pretr...

  12. The effect of facial expressions on respirators contact pressures.

    Cai, Mang; Shen, Shengnan; Li, Hui

    2017-08-01

    This study investigated the effect of four typical facial expressions (calmness, happiness, sadness and surprise) on contact characteristics between an N95 filtering facepiece respirator and a headform. The respirator model comprised two layers (an inner layer and an outer layer) and a nose clip. The headform model was comprised of a skin layer, a fatty tissue layer embedded with eight muscles, and a skull layer. Four typical facial expressions were generated by the coordinated contraction of four facial muscles. After that, the distribution of the contact pressure on the headform, as well as the contact area, were calculated. Results demonstrated that the nasal clip could help make the respirator move closer to the nose bridge while causing facial discomfort. Moreover, contact areas varied with different facial expressions, and facial expressions significantly altered contact pressures at different key areas, which may result in leakage.

  13. The calculus and the design of a miniature quadrupole mass filter: a selected solution from different types of mass analyzers

    Cuna, C.; Ioanoviciu, D.; Lupsa, N.; Chis, A.

    2002-01-01

    The mass spectrometers are very precise tools used in chemical and isotopic analysis for environmental surveillance. Traditionally environmental analysis is done by sampling the soil, air or water and taking the sample back to the laboratory for analysis. To avoid the difficulties related with the sample alteration during the sampling process and the transport the analysis 'in situ' is to be preferred. This type of analysis combines the sampling and analysis and produces an analytical result almost instantly. Fast-response detection methods are highly desirable in cases where relatively short-lived species are to be examined. Theoretically, any type of mass analyzers can be miniaturized, but some are better suited for miniaturization than others. We studied comparatively different types of mass analyzers that can be miniaturized, especially quadrupole, magnetic sector and time of flight types, in view to select from all these, the best solution for our purpose, the application to the 'in situ' environmental monitoring and inspection, analytical process control. We investigated and calculated the properties of some geometrical arrangements that we reported, one of these being a double focusing mass analyzer with electric deflector and magnetic deflector combined in a reversed geometry. From the different calculated versions we selected the following one, with the characteristic parameters: n = 62, f = 2 MHz, L = 0.07 m, r 0 = 2.616 x 10 -3 m, E z = 5 V, R housing = 3.5 r 0 , V m = 1000 V, R max = 200, M max = 200 u. Starting from these mechanical and electrical parameters we calculated and designed a miniature quadrupole mass spectrometer. A theoretical study of the ion trajectories in the quadrupole analyzer by matrix formalism as well as by using Mathieu functions was made. Using the program SIMION 6, the trajectories inside the quadrupole filter were also simulated. The calculus of the ion trajectories starts by numerically solving of the Mathieu type equation

  14. Balanced microwave filters

    Hong, Jiasheng; Medina, Francisco; Martiacuten, Ferran

    2018-01-01

    This book presents and discusses strategies for the design and implementation of common-mode suppressed balanced microwave filters, including, narrowband, wideband, and ultra-wideband filters This book examines differential-mode, or balanced, microwave filters by discussing several implementations of practical realizations of these passive components. Topics covered include selective mode suppression, designs based on distributed and semi-lumped approaches, multilayer technologies, defect ground structures, coupled resonators, metamaterials, interference techniques, and substrate integrated waveguides, among others. Divided into five parts, Balanced Microwave Filters begins with an introduction that presents the fundamentals of balanced lines, circuits, and networks. Part 2 covers balanced transmission lines with common-mode noise suppression, including several types of common-mode filters and the application of such filters to enhance common-mode suppression in balanced bandpass filters. Next, Part 3 exa...

  15. Root Zone Respiration on Hydroponically Grown Wheat Plant Systems

    Soler-Crespo, R. A.; Monje, O. A.

    2010-01-01

    Root respiration is a biological phenomenon that controls plant growth and physiological development during a plant's lifespan. This process is dependent on the availability of oxygen in the system where the plant is located. In hydroponic systems, where plants are submerged in a solution containing vital nutrients but no type of soil, the availability of oxygen arises from the dissolved oxygen concentration in the solution. This oxygen concentration is dependent on the , gas-liquid interface formed on the upper surface of the liquid, as given by Henry's Law, depending on pressure and temperature conditions. Respiration rates of the plants rise as biomass and root zone increase with age. The respiration rate of Apogee wheat plants (Triticum aestivum) was measured as a function of light intensity (catalytic for photosynthesis) and CO2 concentration to determine their effect on respiration rates. To determine their effects on respiration rate and plant growth microbial communities were introduced into the system, by Innoculum. Surfactants were introduced, simulating gray-water usage in space, as another factor to determine their effect on chemical oxygen demand of microbials and on respiration rates of the plants. It is expected to see small effects from changes in CO2 concentration or light levels, and to see root respiration decrease in an exponential manner with plant age and microbial activity.

  16. Performance Improvement of a Prefiltered Synchronous-Reference-Frame PLL By Using a PID-Type Loop Filter

    Golestan, Saeed; Monfared, Mohammad; Frejeido, Francisco

    2014-01-01

    Control Parameters design of a three-phase synchronous reference frame phase locked loop (SRF-PLL) with a pre-filtering stage (acting as the sequence separator) is not a trivial task. The conventional way to deal with this problem is to neglect the interaction between the SRF-PLL and pre-filterin......Control Parameters design of a three-phase synchronous reference frame phase locked loop (SRF-PLL) with a pre-filtering stage (acting as the sequence separator) is not a trivial task. The conventional way to deal with this problem is to neglect the interaction between the SRF-PLL and pre......-integral-derivative controller as the loop filter (instead of the commonly adopted proportionalintegral controller) and arranging a pole-zero cancellation. The suggested method is simple and efficient, and is applicable to the joint operation of different sequence separation techniques and the SRF-PLL. The effectiveness...

  17. Occurrence of trace elements in respirable coal dust

    Sahoo, B.N.

    1991-01-01

    Inhalation of fine particles of coal dust contributes significantly to the occurrence of the disease, pneumoconiosis, prevailing in coal mining community. It is not presently known whether only the coal dust or specific chemical compounds or synergistic effects of several compounds associated with respirable coal dust is responsible for the disease, pneumoconiosis. The present paper describes the quantitative determination of ten minor and trace elements in respirable coal dust particles by atomic absorption spectrophotometric methods. The respirable coal dust samples are collected at the mine atmosphere during drilling in coal scams by using Messrs. Casella's Hexlet apparatus specially designed and fitted with horizontal elutriator to collect the respirable coal dust fraction simulating as near as possible to the lung's retention of the coal miners. After destruction of organic matter by wet oxidation and filtering off clay and silica, Fe, Ca, Mg, Na, K, Mn, Cu, Zn, Cd, and Ni were determined directly in the resulting solution by atomic absorption spectrophotometric procedures. The results show that the trace metals are more acute in lower range of size spectrum. Correlation coefficient, enrichment factor and linear regression values and their inverse relationship between the slope and EF values suggest that, in general, the trace metals in respirable particulates are likely to be from coal derived source if their concentrations are likewise high in the coal. The trace metal analytical data of respirable particulates fitted well to the linear regressive equation. The results of the studies are of importance as it may throw some light on the respirable lung disease 'pneumoconiosis' which are predominant in coal mining community. (author). 13 refs., 6 tabs

  18. Quantitative respirator man-testing at Rocky Flats

    Leigh, J.D.

    The dioctyl phthalate quantitative respirator man-testing method used at Rocky Flats is outlined. Using this method, 93 persons trained to use self contained breathing equipment were tested with eight respiratory protective devices. Test results obtained with the seven devices using high efficiency particulate filters are compared to the results obtained with the self contained breathing equipment. Also comparison is made for these results to test results for 1667 other employees

  19. Quantitative respirator man-testing at Rocky Flats

    Leigh, J. D.

    1978-01-01

    The dioctyl phthalate quantitative respirator man-testing method used at Rocky Flats is outlined. Using this method, 93 persons trained to use self contained breathing equipment were tested with eight respiratory protective devices. Test results obtained with the seven devices using high efficiency particulate filters are compared to the results obtained with the self contained breathing equipment. Also comparison is made for these results to test results for 1667 other employees.

  20. Filter arrays

    Page, Ralph H.; Doty, Patrick F.

    2017-08-01

    The various technologies presented herein relate to a tiled filter array that can be used in connection with performance of spatial sampling of optical signals. The filter array comprises filter tiles, wherein a first plurality of filter tiles are formed from a first material, the first material being configured such that only photons having wavelengths in a first wavelength band pass therethrough. A second plurality of filter tiles is formed from a second material, the second material being configured such that only photons having wavelengths in a second wavelength band pass therethrough. The first plurality of filter tiles and the second plurality of filter tiles can be interspersed to form the filter array comprising an alternating arrangement of first filter tiles and second filter tiles.

  1. Push-Broom-Type Very High-Resolution Satellite Sensor Data Correction Using Combined Wavelet-Fourier and Multiscale Non-Local Means Filtering

    Kang, Wonseok; Yu, Soohwan; Seo, Doochun; Jeong, Jaeheon; Paik, Joonki

    2015-01-01

    In very high-resolution (VHR) push-broom-type satellite sensor data, both destriping and denoising methods have become chronic problems and attracted major research advances in the remote sensing fields. Since the estimation of the original image from a noisy input is an ill-posed problem, a simple noise removal algorithm cannot preserve the radiometric integrity of satellite data. To solve these problems, we present a novel method to correct VHR data acquired by a push-broom-type sensor by combining wavelet-Fourier and multiscale non-local means (NLM) filters. After the wavelet-Fourier filter separates the stripe noise from the mixed noise in the wavelet low- and selected high-frequency sub-bands, random noise is removed using the multiscale NLM filter in both low- and high-frequency sub-bands without loss of image detail. The performance of the proposed method is compared to various existing methods on a set of push-broom-type sensor data acquired by Korean Multi-Purpose Satellite 3 (KOMPSAT-3) with severe stripe and random noise, and the results of the proposed method show significantly improved enhancement results over existing state-of-the-art methods in terms of both qualitative and quantitative assessments. PMID:26378532

  2. Air-assisted dispersive liquid-liquid microextraction based on a new hydrophobic deep eutectic solvent for the preconcentration of benzophenone-type UV filters from aqueous samples.

    Ge, Dandan; Zhang, Yi; Dai, Yixiu; Yang, Shumin

    2018-04-01

    Deep eutectic solvents are considered as new and green solvents that can be widely used in analytical chemistry such as microextraction. In the present work, a new dl-menthol-based hydrophobic deep eutectic solvent was synthesized and used as extraction solvents in an air-assisted dispersive liquid-liquid microextraction method for preconcentration and extraction of benzophenone-type UV filters from aqueous samples followed by high-performance liquid chromatography with diode array detection. In an experiment, the deep eutectic solvent formed by dl-menthol and decanoic acid was added to an aqueous solution containing the UV filters, and then the mixture was sucked up and injected five times by using a glass syringe, and a cloudy state was achieved. After extraction, the solution was centrifuged and the upper phase was subjected to high-performance liquid chromatography for analysis. Various parameters such as the type and volume of the deep eutectic solvent, number of pulling, and pushing cycles, solution pH and salt concentration were investigated and optimized. Under the optimum conditions, the developed method exhibited low limits of detection and limits of quantitation, good linearity, and precision. Finally, the proposed method was successfully applied to determine the benzophenone-type filters in environmental water samples with relative recoveries of 88.8-105.9%. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Neutron Beam Filters

    Adib, M.

    2011-01-01

    The purpose of filters is to transmit neutrons with selected energy, while remove unwanted ones from the incident neutron beam. This reduces the background, and the number of spurious. The types of commonly used now-a-day neutron filters and their properties are discussed in the present work. There are three major types of neutron filters. The first type is filter of selective thermal neutron. It transmits the main reflected neutrons from a crystal monochromate, while reject the higher order contaminations accompanying the main one. Beams coming from the moderator always contain unwanted radiation like fast neutrons and gamma-rays which contribute to experimental background and to the biological hazard potential. Such filter type is called filter of whole thermal neutron spectrum. The third filter type is it transmits neutrons with energies in the resonance energy range (En . 1 KeV). The main idea of such neutron filter technique is the use of large quantities of a certain material which have the deep interference minima in its total neutron cross-section. By transmitting reactor neutrons through bulk layer of such material, one can obtain the quasimonochromatic neutron lines instead of white reactor spectrum.

  4. Did Respiration or Photosynthesis Come First

    Broda, E.

    1979-01-01

    The similarity of the mechanisms in photosynthetic and in oxidative phosphorylation suggests a common origin ( convers ion hypothesis). It is proposed that an early form of electron flow with oxidative phosphorylation ("prerespiration"), to terminal electron acceptors available in a reducing biosphere, was supplemented by a photocatalyst capable of a redox reaction. In this way, cyclic photophosphorylation arose. Further stages in evolution were reverse electron flow powered by ATP, to make NADH as a reductant for CO2 , and subsequently noncyclic electron flow. These processes concomitantly provided the oxidants indispensable for full development of oxidative phosphorylation, i.e. for normal respiration: sulphate, O2 and with participation of the nitrificants, nitrite and nitrate. Thus, prerespiration preceded photosynthesis, and this preceded respiration. It is also suggested that nonredox photoprocesses of the Halobacterium type are not part of the mainstream of bioenergetic evolution. They do not lead to photoprocesses with electron flow. (author)

  5. Temperature response of soil respiration largely unaltered with experimental warming

    Carey, Joanna C.; Tang, Jianwu; Templer, Pamela H.; Kroeger, Kevin D.; Crowther, Thomas W.; Burton, Andrew J.; Dukes, Jeffrey S.; Emmett, Bridget; Frey, Serita D.; Heskel, Mary A.; Jiang, Lifen; Machmuller, Megan B.; Mohan, Jacqueline; Panetta, Anne Marie; Reich, Peter B.; Reinsch, Sabine; Wang, Xin; Allison, Steven D.; Bamminger, Chris; Bridgham, Scott; Collins, Scott L.; de Dato, Giovanbattista; Eddy, William C.; Enquist, Brian J.; Estiarte, Marc; Harte, John; Henderson, Amanda; Johnson, Bart R.; Steenberg Larsen, Klaus; Luo, Yiqi; Marhan, Sven; Melillo, Jerry M.; Penuelas, Josep; Pfeifer-Meister, Laurel; Poll, Christian; Rastetter, Edward B.; Reinmann, Andrew B.; Reynolds, Lorien L.; Schmidt, Inger K.; Shaver, Gaius R.; Strong, Aaron L.; Suseela, Vidya; Tietema, Albert

    2016-01-01

    The respiratory release of carbon dioxide (CO2) from soil is a major yet poorly understood flux in the global carbon cycle. Climatic warming is hypothesized to increase rates of soil respiration, potentially fueling further increases in global temperatures. However, despite considerable scientific attention in recent decades, the overall response of soil respiration to anticipated climatic warming remains unclear. We synthesize the largest global dataset to date of soil respiration, moisture, and temperature measurements, totaling >3,800 observations representing 27 temperature manipulation studies, spanning nine biomes and over 2 decades of warming. Our analysis reveals no significant differences in the temperature sensitivity of soil respiration between control and warmed plots in all biomes, with the exception of deserts and boreal forests. Thus, our data provide limited evidence of acclimation of soil respiration to experimental warming in several major biome types, contrary to the results from multiple single-site studies. Moreover, across all nondesert biomes, respiration rates with and without experimental warming follow a Gaussian response, increasing with soil temperature up to a threshold of ∼25 °C, above which respiration rates decrease with further increases in temperature. This consistent decrease in temperature sensitivity at higher temperatures demonstrates that rising global temperatures may result in regionally variable responses in soil respiration, with colder climates being considerably more responsive to increased ambient temperatures compared with warmer regions. Our analysis adds a unique cross-biome perspective on the temperature response of soil respiration, information critical to improving our mechanistic understanding of how soil carbon dynamics change with climatic warming.

  6. A Novel Algorithm for Determining Contact Area Between a Respirator and a Headform

    Lei, Zhipeng; Yang, James; Zhuang, Ziqing

    2014-01-01

    The contact area, as well as the contact pressure, is created when a respiratory protection device (a respirator or surgical mask) contacts a human face. A computer-based algorithm for determining the contact area between a headform and N95 filtering facepiece respirator (FFR) was proposed. Six N95 FFRs were applied to five sizes of standard headforms (large, medium, small, long/narrow, and short/wide) to simulate respirator donning. After the contact simulation between a headform and an N95 ...

  7. Mitochondrial Respiration and Oxygen Tension.

    Shaw, Daniel S; Meitha, Karlia; Considine, Michael J; Foyer, Christine H

    2017-01-01

    Measurements of respiration and oxygen tension in plant organs allow a precise understanding of mitochondrial capacity and function within the context of cellular oxygen metabolism. Here we describe methods that can be routinely used for the isolation of intact mitochondria, and the determination of respiratory electron transport, together with techniques for in vivo determination of oxygen tension and measurement of respiration by both CO 2 production and O 2 consumption that enables calculation of the respiratory quotient [CO 2 ]/[O 2 ].

  8. Respirable versus inhalable dust sampling

    Hondros, J.

    1987-01-01

    The ICRP uses a total inhalable dust figure as the basis of calculations on employee lung dose. This paper was written to look at one aspect of the Olympic Dam dust situation, namely, the inhalable versus respirable fraction of the dust cloud. The results of this study will determine whether it is possible to use respirable dust figures, as obtained during routine monitoring to help in the calculations of employee exposure to internal radioactive contaminants

  9. Interpreting, measuring, and modeling soil respiration

    Michael G. Ryan; Beverly E. Law

    2005-01-01

    This paper reviews the role of soil respiration in determining ecosystem carbon balance, and the conceptual basis for measuring and modeling soil respiration. We developed it to provide background and context for this special issue on soil respiration and to synthesize the presentations and discussions at the workshop. Soil respiration is the largest component of...

  10. The effect of cold aqueous extract of lemon peel against types of bacteria isolated from the cooling devices Filters

    Ashraf S. Hassan

    2017-11-01

    Full Text Available The antibacterial effect of citrus peel lemon against the bacterial strains obtained from the filters of air conditioners have been selected based on the presence most in these filters such as Streptococcus, Bacillus spp, Pseudomonas, E coli. agar well diffusion method used to evaluate antibacterial activity of citrus peels water extract. through the results became clear to us that the cold aqueous extract of lemon peel showed a significant effect on the growth of bacterial species through the diameters of inhibition zone that appeared in all concentrations of the extract (125, 250, 500, 1000 mg/ml. Gram-positive bacteria Streptococcus spp were the most affected Where the diameters of inhibition zone (18, 15, 12, 0, 0 mm respectively, while The Gram-negative bacteria E coli least affected. The results obtained in this study indicate that citrus lemon peel can be used in the treatment of diseases caused by organisms for the purposes of the pharmaceutical.

  11. Control of respirable particles and radon progeny with portable air cleaners

    Offermann, F.J.; Sextro, R.G.; Fisk, W.J.; Nazaroff, W.W.; Nero, A.V.; Revzan, K.L.; Yater, J.

    1984-02-01

    Eleven portable air cleaning devices have been evaluated for control of indoor concentrations of respirable particles and radon progeny. Following injection of cigarette smoke and radon in a room-size chamber, decay rates for particles and radon progeny concentrations were measured with and without air cleaner operation. Particle concentrations were obtained for total number concentration and for number concentration by particle size. In tests with no air cleaner the natural decay rate for cigarette smoke was observed to be 0.2 hr -1 . Air cleaning rates for particles were found to be negligible for several small panel-filters, a residential ion-generator, and a pair of mixing fans. The electrostatic precipitators and extended surface filters tested had significant particle removal rates, and a HEPA-type filter was the most efficient air cleaner. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in removing radon progeny. At low particle concentrations plateout of the unattached radon progeny is an important removal mechanism. Based on data from these tests, the plateout rate for unattached progeny was found to be 15 hr -1 . The unattached fraction and the overall removal rate due to deposition of attached and unattached nuclides have been estimated for each radon decay product as a function of particle concentration. While air cleaning can be effective in reducing total radon progeny, concentrations of unattached radon progeny can increase with increasing air cleaning. 39 references, 26 figures, 9 tables

  12. Estimation of State of Charge for Two Types of Lithium-Ion Batteries by Nonlinear Predictive Filter for Electric Vehicles

    Yin Hua

    2015-04-01

    Full Text Available Estimation of state of charge (SOC is of great importance for lithium-ion (Li-ion batteries used in electric vehicles. This paper presents a state of charge estimation method using nonlinear predictive filter (NPF and evaluates the proposed method on the lithium-ion batteries with different chemistries. Contrary to most conventional filters which usually assume a zero mean white Gaussian process noise, the advantage of NPF is that the process noise in NPF is treated as an unknown model error and determined as a part of the solution without any prior assumption, and it can take any statistical distribution form, which improves the estimation accuracy. In consideration of the model accuracy and computational complexity, a first-order equivalent circuit model is applied to characterize the battery behavior. The experimental test is conducted on the LiCoO2 and LiFePO4 battery cells to validate the proposed method. The results show that the NPF method is able to accurately estimate the battery SOC and has good robust performance to the different initial states for both cells. Furthermore, the comparison study between NPF and well-established extended Kalman filter for battery SOC estimation indicates that the proposed NPF method has better estimation accuracy and converges faster.

  13. A mechanical breathing simulator for respirator test

    Murata, Mikio; Ikezawa, Yoshio; Yoshida, Yoshikazu

    1976-01-01

    A mechanical breathing simulator has been developed to produce the human respiration for use in respirator test. The respirations were produced through the strokes of piston controlled by a rockerarm with adjustable fulcrum. The respiration rate was governed by motor-speed control, independent of the tidal volume achieved by adjustment of the piston stroke. By the breather, the simulated respirations for work rate 0, 208, 415, 622 and 830 kg-m/min could be produced through the typical dummy head. (auth.)

  14. Respirator studies for the Nuclear Regulatory Commission. Protection factors for supplied-air respirators. Progress report, October 1, 1976--September 30, 1977

    Hack, A.; Bradley, O.D.; Trujillo, A.

    1977-12-01

    This report describes the work performed during FY 1977 for the Nuclear Regulatory Commission. The Protection Factors (efficiency) provided by 25 NIOSH approved supplied-air respirators were determined while the devices were worn by a panel of anthropometrically selected test subjects. The major recommendation was that demand-type respirators should neither be used nor approved

  15. Rectifier Filters

    Y. A. Bladyko

    2010-01-01

    Full Text Available The paper contains definition of a smoothing factor which is suitable for any rectifier filter. The formulae of complex smoothing factors have been developed for simple and complex passive filters. The paper shows conditions for application of calculation formulae and filters

  16. Two Proximal Skin Electrodes — A Respiration Rate Body Sensor

    Viktor Avbelj

    2012-10-01

    Full Text Available We propose a new body sensor for extracting the respiration rate based on the amplitude changes in the body surface potential differences between two proximal body electrodes. The sensor could be designed as a plaster-like reusable unit that can be easily fixed onto the surface of the body. It could be equipped either with a sufficiently large memory for storing the measured data or with a low-power radio system that can transmit the measured data to a gateway for further processing. We explore the influence of the sensor’s position on the quality of the extracted results using multi-channel ECG measurements and considering all the pairs of two neighboring electrodes as potential respiration-rate sensors. The analysis of the clinical measurements, which also include reference thermistor-based respiration signals, shows that the proposed approach is a viable option for monitoring the respiration frequency and for a rough classification of breathing types. The obtained results were evaluated on a wireless prototype of a respiration body sensor. We indicate the best positions for the respiration body sensor and prove that a single sensor for body surface potential difference on proximal skin electrodes can be used for combined measurements of respiratory and cardiac activities.

  17. ASIC and ENaC type sodium channels: conformational states and the structures of the ion selectivity filters.

    Hanukoglu, Israel

    2017-02-01

    The acid-sensing ion channels (ASICs) and epithelial sodium channels (ENaC) are members of a superfamily of channels that play critical roles in mechanosensation, chemosensation, nociception, and regulation of blood volume and pressure. These channels look and function like a tripartite funnel that directs the flow of Na + ions into the cytoplasm via the channel pore in the membrane. The subunits that form these channels share a common structure with two transmembrane segments (TM1 and TM2) and a large extracellular part. In most vertebrates, there are five paralogous genes that code for ASICs (ASIC1-ASIC5), and four for ENaC subunits alpha, beta, gamma, and delta (α, β, γ, and δ). While ASICs can form functional channels as a homo- or heterotrimer, ENaC functions as an obligate heterotrimer composed of α-β-γ or β-γ-δ subunits. The structure of ASIC has been determined in several conformations, including desensitized and open states. This review presents a comparison of the structures of these states using easy-to-understand molecular models of the full complex, the central tunnel that includes an outer vestibule, the channel pore, and ion selectivity filter. The differences in the secondary, tertiary, and quaternary structures of the states are summarized to pinpoint the conformational changes responsible for channel opening. Results of site-directed mutagenesis studies of ENaC subunits are examined in light of ASIC1 models. Based on these comparisons, a molecular model for the selectivity filter of ENaC is built by in silico mutagenesis of an ASIC1 structure. These models suggest that Na + ions pass through the filter in a hydrated state. © 2016 Federation of European Biochemical Societies.

  18. Failure of action potential propagation in sensory neurons: mechanisms and loss of afferent filtering in C-type units after painful nerve injury.

    Gemes, Geza; Koopmeiners, Andrew; Rigaud, Marcel; Lirk, Philipp; Sapunar, Damir; Bangaru, Madhavi Latha; Vilceanu, Daniel; Garrison, Sheldon R; Ljubkovic, Marko; Mueller, Samantha J; Stucky, Cheryl L; Hogan, Quinn H

    2013-02-15

    The T-junction of sensory neurons in the dorsal root ganglion (DRG) is a potential impediment to action potential (AP) propagation towards the CNS. Using intracellular recordings from rat DRG neuronal somata during stimulation of the dorsal root, we determined that the maximal rate at which all of 20 APs in a train could successfully transit the T-junction (following frequency) was lowest in C-type units, followed by A-type units with inflected descending limbs of the AP, and highest in A-type units without inflections. In C-type units, following frequency was slower than the rate at which AP trains could be produced in either dorsal root axonal segments or in the soma alone, indicating that the T-junction is a site that acts as a low-pass filter for AP propagation. Following frequency was slower for a train of 20 APs than for two, indicating that a cumulative process leads to propagation failure. Propagation failure was accompanied by diminished somatic membrane input resistance, and was enhanced when Ca(2+)-sensitive K(+) currents were augmented or when Ca(2+)-sensitive Cl(-) currents were blocked. After peripheral nerve injury, following frequencies were increased in axotomized C-type neurons and decreased in axotomized non-inflected A-type neurons. These findings reveal that the T-junction in sensory neurons is a regulator of afferent impulse traffic. Diminished filtering of AP trains at the T-junction of C-type neurons with axotomized peripheral processes could enhance the transmission of activity that is ectopically triggered in a neuroma or the neuronal soma, possibly contributing to pain generation.

  19. ECG-derived respiration methods: adapted ICA and PCA.

    Tiinanen, Suvi; Noponen, Kai; Tulppo, Mikko; Kiviniemi, Antti; Seppänen, Tapio

    2015-05-01

    Respiration is an important signal in early diagnostics, prediction, and treatment of several diseases. Moreover, a growing trend toward ambulatory measurements outside laboratory environments encourages developing indirect measurement methods such as ECG derived respiration (EDR). Recently, decomposition techniques like principal component analysis (PCA), and its nonlinear version, kernel PCA (KPCA), have been used to derive a surrogate respiration signal from single-channel ECG. In this paper, we propose an adapted independent component analysis (AICA) algorithm to obtain EDR signal, and extend the normal linear PCA technique based on the best principal component (PC) selection (APCA, adapted PCA) to improve its performance further. We also demonstrate that the usage of smoothing spline resampling and bandpass-filtering improve the performance of all EDR methods. Compared with other recent EDR methods using correlation coefficient and magnitude squared coherence, the proposed AICA and APCA yield a statistically significant improvement with correlations 0.84, 0.82, 0.76 and coherences 0.90, 0.91, 0.85 between reference respiration and AICA, APCA and KPCA, respectively. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  20. Respirator use and its impact on particulate matter exposure in aluminum manufacturing facilities.

    Liu, Sa; Noth, Elizabeth; Eisen, Ellen; Cullen, Mark R; Hammond, Katharine

    2018-05-31

    Objectives As part of a large epidemiologic study of particulate health effect, this study aimed to report respirator use among total particulate matter (TPM) samples collected in a major aluminum manufacturing company from 1966‒2013 and evaluate the impact of respirator-use adjustment on exposure estimation. Methods Descriptive analyses were performed to evaluate respirator use across facilities and by facility type and job. Protection factors were applied to TPM measurements for recorded respirator use. Estimated TPM exposure for each job ‒ before and after respirator-use adjustment ‒ were compared to assess the impact of adjustment on exposure estimation. Results Respirator use was noted for 37% of 12 402 full-shift personal TPM samples. Measured TPM concentration ranged from less than detectable to 8220 mg/m3, with arithmetic mean, median and standard deviation being 10.6, 0.87 and 130 mg/m 3 , respectively. Respirators were used more often in smelting facilities (52% of TPM measurements) than in fabricating (17%) or refinery facilities (28%) (Pfacilities were subject to respirator-use adjustment, whereas it was 20% and 70% in fabricating and refinery facilities, respectively. Applying protection factors to TPM measurements significantly reduced estimated job mean TPM exposures and changed exposure categories in these facilities, with larger impact in smelting than fabricating facilities. Conclusions Respirator use varied by time, facility and job. Adjusting respirator use resulted in differential impact in smelting and fabricating facilities, which will need to be incorporated into ongoing epidemiologic studies accordingly.

  1. Facepiece leakage and fitting of respirators

    White, J.M.

    1978-05-01

    The ways in which airborne contaminants can penetrate respirators and the factors which affect the fit of respirators are discussed. The fit of the respirator to the face is shown to be the most critical factor affecting the protection achieved by the user. Qualitative and quantitative fit testing techniques are described and their application to industrial respirator programs is examined. Quantitative measurement of the leakage of a respirator while worn can be used to numerically indicate the protection achieved. These numbers, often referred to as protection factors, are sometimes used as the basis for selecting suitable respirators and this practice is reviewed. (author)

  2. Shifted-modified Chebyshev filters

    ŞENGÜL, Metin

    2013-01-01

    This paper introduces a new type of filter approximation method that utilizes shifted-modified Chebyshev filters. Construction of the new filters involves the use of shifted-modified Chebyshev polynomials that are formed using the roots of conventional Chebyshev polynomials. The study also includes 2 tables containing the shifted-modified Chebyshev polynomials and the normalized element values for the low-pass prototype filters up to degree 6. The transducer power gain, group dela...

  3. Analysis of the implementation of a sand bed type filter for the venting of a nuclear power plant; Analisis de la implementacion de un filtro tipo lecho de arena para el venteo de una central nuclear

    Cuevas V, D.; Sainz M, E.; Ortiz V, J., E-mail: delfy.cu@gmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2017-09-15

    The filtered venting of the containment has been adopted in European countries to mitigate the consequences derived from the excess pressure of the containment during a severe accident. When venting has taken place, the fission products are released directly into the environment, unless a filter is placed in the path of the same, so various types of filters are used to trap the fission products. The containment venting filters currently installed use different filtering technologies that involve more than one medium. Those who use water as the first stage of filtration are called wet systems, are equipped with additional stages to eliminate water drops and emissions of fine aerosols, and may even be equipped with an element that contains certain means of absorption for the gaseous iodine species filtration. Other designs, based on deep bed filtration as the main retention stage, called dry filters; use metal fiber, ceramic or sand filtration media to trap aerosols. The present work evaluates the hydraulic characteristics of the sand bed type filter designed by EDF as a candidate to be installed in the containment of the BWR Mark II (primary containment type of the Laguna Verde nuclear power plant). The evaluation of the sand bed filter was performed using the OpenFOAM open source software package. Models of each zone of the filtering device were generated and by means of a series of parametric calculations of computational fluid mechanics, the relevant hydrodynamic characteristics of the device were obtained, such as pressure drops against mass flow and pressure fields and velocity under different operating conditions. On the other hand, the validation of the sand bed filter model was made when comparing the results of experimental tests carried out in a sand column of the PITEAS program (1985-1986) against the simulation in OpenFOAM. The results obtained are very close to those obtained experimentally. (Author)

  4. Deeply-etched micromirror with vertical slit and metallic coating enabling transmission-type optical MEMS filters

    Othman, Muhammad A.; Sabry, Yasser M.; Sadek, Mohamed; Nassar, Ismail M.; Khalil, Diaa A.

    2016-03-01

    In this work we report a novel optical MEMS deeply-etched mirror with metallic coating and vertical slot, where the later allows reflection and transmission by the micromirror. The micromirror as well as fiber grooves are fabricated using deep reactive ion etching technology, where the optical axis is in-plane and the components are self-aligned. The etching depth is 150 μm chosen to improve the micromirror optical throughput. The vertical optical structure is Al metal coated using the shadow mask technique. A fiber-coupled Fabry-Pérot filter is successfully realized using the fabricated structure. Experimental measurements were obtained based on a dielectric-coated optical fiber inserted into a fiber groove facing the slotted micromirror. A versatile performance in terms of the free spectral range and 3-dB bandwidth is achieved.

  5. Respirators and protective clothing

    1967-01-01

    The basic object in the use of protective clothing and equipment is to prevent contamination of the skin and to prevent inhalation and ingestion of radioactive isotopes or other toxic materials. This book is a guide to deciding the kind and quantity of protective equipment needed for a particular type of laboratory or operation.

  6. Transcriptional regulation of respiration in yeast metabolizing differently repressive carbon substrates

    Fendt Sarah-Maria

    2010-02-01

    Full Text Available Abstract Background Depending on the carbon source, Saccharomyces cerevisiae displays various degrees of respiration. These range from complete respiration as in the case of ethanol, to almost complete fermentation, and thus very low degrees of respiration on glucose. While many key regulators are known for these extreme cases, we focus here on regulators that are relevant at intermediate levels of respiration. Results We address this question by linking the functional degree of respiration to transcriptional regulation via enzyme abundances. Specifically, we investigated aerobic batch cultures with the differently repressive carbon sources glucose, mannose, galactose and pyruvate. Based on 13C flux analysis, we found that the respiratory contribution to cellular energy production was largely absent on glucose and mannose, intermediate on galactose and highest on pyruvate. In vivo abundances of 40 respiratory enzymes were quantified by GFP-fusions under each condition. During growth on the partly and fully respired substrates galactose and pyruvate, several TCA cycle and respiratory chain enzymes were significantly up-regulated. From these enzyme levels and the known regulatory network structure, we determined the probability for a given transcription factor to cause the coordinated expression changes. The most probable transcription factors to regulate the different degrees of respiration were Gcr1p, Cat8p, the Rtg-proteins and the Hap-complex. For the latter three ones we confirmed their importance for respiration by quantifying the degree of respiration and biomass yields in the corresponding deletion strains. Conclusions Cat8p is required for wild-type like respiration, independent of its known activation of gluconeogenic genes. The Rtg-proteins and the Hap-complex are essential for wild-type like respiration under partially respiratory conditions. Under fully respiratory conditions, the Hap-complex, but not the Rtg-proteins are essential

  7. Transcriptional regulation of respiration in yeast metabolizing differently repressive carbon substrates.

    Fendt, Sarah-Maria; Sauer, Uwe

    2010-02-18

    Depending on the carbon source, Saccharomyces cerevisiae displays various degrees of respiration. These range from complete respiration as in the case of ethanol, to almost complete fermentation, and thus very low degrees of respiration on glucose. While many key regulators are known for these extreme cases, we focus here on regulators that are relevant at intermediate levels of respiration. We address this question by linking the functional degree of respiration to transcriptional regulation via enzyme abundances. Specifically, we investigated aerobic batch cultures with the differently repressive carbon sources glucose, mannose, galactose and pyruvate. Based on 13C flux analysis, we found that the respiratory contribution to cellular energy production was largely absent on glucose and mannose, intermediate on galactose and highest on pyruvate. In vivo abundances of 40 respiratory enzymes were quantified by GFP-fusions under each condition. During growth on the partly and fully respired substrates galactose and pyruvate, several TCA cycle and respiratory chain enzymes were significantly up-regulated. From these enzyme levels and the known regulatory network structure, we determined the probability for a given transcription factor to cause the coordinated expression changes. The most probable transcription factors to regulate the different degrees of respiration were Gcr1p, Cat8p, the Rtg-proteins and the Hap-complex. For the latter three ones we confirmed their importance for respiration by quantifying the degree of respiration and biomass yields in the corresponding deletion strains. Cat8p is required for wild-type like respiration, independent of its known activation of gluconeogenic genes. The Rtg-proteins and the Hap-complex are essential for wild-type like respiration under partially respiratory conditions. Under fully respiratory conditions, the Hap-complex, but not the Rtg-proteins are essential for respiration.

  8. Hydrodynamic calculation of a filter sand bed type used in the containment venting systems; Calculo hidrodinamico de un filtro tipo lecho de arena usado en los sistemas de venteo de la contencion

    Cuevas V, D.; Sainz M, E.; Ortiz V, J., E-mail: delfy.cu@gmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2015-09-15

    The filtered venting of the containment has been adopted in European countries to mitigate the consequences of excess pressure containment during a severe accident. When venting has taken place, the fission products are released directly into the environment, unless a filter on the same path is placed, so that various types of filters are used to trap the fission products. The venting filters of the containment currently installed use different filtration technologies that involve more than one medium. Those using water as the first stage of filtration are called wet systems and are equipped with additional steps to remove water drops and fine aerosols emissions. And even they may also be equipped with an element containing certain absorption means for the filtration of gaseous iodine species. Other designs based on filtration of deep bed as the primary retention step; called dry filters, use filtration media of metal fiber, ceramic or sand to trap aerosols. This paper evaluates the hydraulic characteristics of the filter sand bed type designed by EDF as a candidate to be installed in the containment of BWR Mark II (type of primary containment of the nuclear power plant of Laguna Verde). The evaluation of filter sand bed type was performed using the software package of open source OpenFOAM. Models of each zone of the filtered device were generated and through a series of parametric calculations of computational fluid mechanics relevant hydrodynamic characteristics of the device were obtained, such as pressure drops against mass flow rate and pressure fields and speed at different operating conditions. On the other hand, the model validation of the sand bed filter when comparing the results of experimental tests on a sand column of PITEAS program (1985-1986) against OpenFOAM simulation was realized. The results are very close to those obtained experimentally. (Author)

  9. Filter assembly for metallic and intermetallic tube filters

    Alvin, Mary Anne; Lippert, Thomas E.; Bruck, Gerald J.; Smeltzer, Eugene E.

    2001-01-01

    A filter assembly (60) for holding a filter element (28) within a hot gas cleanup system pressure vessel is provided, containing: a filter housing (62), said filter housing having a certain axial length and having a peripheral sidewall, said sidewall defining an interior chamber (66); a one piece, all metal, fail-safe/regenerator device (68) within the interior chamber (66) of the filter housing (62) and/or extending beyond the axial length of the filter housing, said device containing an outward extending radial flange (71) within the filter housing for seating an essential seal (70), the device also having heat transfer media (72) disposed inside and screens (80) for particulate removal; one compliant gasket (70) positioned next to and above the outward extending radial flange of the fail-safe/regenerator device; and a porous metallic corrosion resistant superalloy type filter element body welded at the bottom of the metal fail-safe/regenerator device.

  10. General Instructions for Disposable Respirators

    2009-04-09

    This podcast, intended for the general public, demonstrates how to put on and take off disposable respirators that are to be used in areas affected by the influenza outbreak.  Created: 4/9/2009 by CDC, National Institute for Occupational Safety and Health (NIOSH).   Date Released: 4/29/2009.

  11. Use of Facemasks and Respirators

    2007-05-15

    This program demonstrates the differences of facemasks and respirators that are to be used in public settings during an influenza pandemic.  Created: 5/15/2007 by CDC, National Institute for Occupational Safety and Health (NIOSH).   Date Released: 5/25/2007.

  12. Analysis of the radioactive aerosols sampled with Lepestok respirators during work in the Chernobyl' NPP region

    Borisova, L.I.; Polevov, V.N.; Borisov, N.B.; Basmanov, P.I.

    1989-01-01

    Aerosols sampled with Lepestok type respirators in the Chernobyl' NPP region following the accident were analysed by gamma-spectroscopic and optical-radiographic methods and nuclide ratio of the aerosol sediment after respirators usage were determined. Parameters of the sampled gamma-active aerosol particles were obtained. ref. 1; tabs. 3

  13. Tillage Effects on Soil Properties & Respiration

    Rusu, Teodor; Bogdan, Ileana; Moraru, Paula; Pop, Adrian; Duda, Bogdan; Cacovean, Horea; Coste, Camelia

    2015-04-01

    Soil tillage systems can be able to influence soil compaction, water dynamics, soil temperature and soil structural condition. These processes can be expressed as changes of soil microbiological activity, soil respiration and sustainability of agriculture. Objectives of this study were: 1) to assess the effects of tillage systems (Conventional System-CS, Minimum Tillage-MT, No-Tillage-NT) on soil compaction, soil temperature, soil moisture and soil respiration and 2) to establish the relationship that exists in changing soil properties. Three treatments were installed: CS-plough + disc; MT-paraplow + rotary grape; NT-direct sowing. The study was conducted on an Argic-Stagnic Faeoziom. The MT and NT applications reduce or completely eliminate the soil mobilization, due to this, soil is compacted in the first year of application. The degree of compaction is directly related to soil type and its state of degradation. The state of soil compaction diminished over time, tending toward a specific type of soil density. Soil moisture was higher in NT and MT at the time of sowing and in the early stages of vegetation and differences diminished over time. Moisture determinations showed statistically significant differences. The MT and NT applications reduced the thermal amplitude in the first 15 cm of soil depth and increased the soil temperature by 0.5-2.20C. The determinations confirm the effect of soil tillage system on soil respiration; the daily average was lower at NT (315-1914 mmoli m-2s-1) and followed by MT (318-2395 mmoli m-2s-1) and is higher in the CS (321-2480 mmol m-2s-1). Comparing with CS, all the two conservation tillage measures decreased soil respiration, with the best effects of no-tillage. An exceeding amount of CO2 produced in the soil and released into the atmosphere, resulting from aerobic processes of mineralization of organic matter (excessive loosening) is considered to be not only a way of increasing the CO2 in the atmosphere, but also a loss of

  14. SU-F-T-521: Flattening-Filter-Free Beam Parameters Comparison From Different Linac Machine Types

    Hussain, A [King Faisal Specialist Hospital, Riyadh, Saudi Arabia, Arkansas Cancer Institute, Pine Bluff, AR (Saudi Arabia)

    2016-06-15

    Purpose: Novel linac machines, TrueBeam (TB) and Elekta Versa have updated head designing and software control system, include flattening-filter-free (FFF) photon and electron beams. Later on FFF beams were also introduced on C-Series machines. In this work FFF beams for same energy 6MV but from different machine versions were studied with reference to beam data parameters. Methods: The 6MV-FFF percent depth doses, profile symmetry and flatness, dose rate tables, and multi-leaf collimator (MLC) transmission factors were measured during commissioning process of both C-series and Truebeam machines. The scanning and dosimetric data for 6MV-FFF beam from Truebeam and C-Series linacs was compared. A correlation of 6MV-FFF beam from Elekta Versa with that of Varian linacs was also found. Results: The scanning files were plotted for both qualitative and quantitative analysis. The dosimetric leaf gap (DLG) for C-Series 6MV-FFF beam is 1.1 mm. Published values for Truebeam dosimetric leaf gap is 1.16 mm. 6MV MLC transmission factor varies between 1.3 % and 1.4 % in two separate measurements and measured DLG values vary between 1.32 mm and 1.33 mm on C-Series machine. MLC transmission factor from C-Series machine varies between 1.5 % and 1.6 %. Some of the measured data values from C-Series FFF beam are compared with Truebeam representative data. 6MV-FFF beam parameter values like dmax, OP factors, beam symmetry and flatness and additional parameters for C-Series and Truebeam liancs will be presented and compared in graphical form and tabular data form if selected. Conclusion: The 6MV flattening filter (FF) beam data from C-Series & Truebeam and 6MV-FFF beam data from Truebeam has already presented. This particular analysis to compare 6MV-FFF beam from C-Series and Truebeam provides opportunity to better elaborate FFF mode on novel machines. It was found that C-Series and Truebeam 6MV-FFF dosimetric and beam data was quite similar.

  15. Enhancement of the power system efficiency using the hybrid-type harmonic filters for a KSTAR nuclear fusion experimental system

    Yoon, Dong-Hee; Lee, Hansang; Park, Byungju; Jang, Gilsoo

    2011-01-01

    Highlights: → The low power factor and power quality problems are occurred by the operation of the PF facility in KSTAR system. We model the power system of KSTAR system including the PF facility. We show a method of the filter insertion to improve the problem and conduct the simulations to verify our method. - Abstract: The KSTAR system, which includes a large amount of nonlinear load, is a relatively high reactive power consumption load which injects harmonic currents into the power system which could result in the possibility for a power system perturbation to occur in the transmission lines, affecting nearby customers. In order to maintain the power quality and power factor in the inner system of the KSTAR system and the adjacent distribution lines, the assessment of the effect of the DC power supply in the KSTAR system is required for appropriate countermeasures to be put in place. In this paper, on the basis of a preliminary inspection of the power system near a KSTAR system, the simulation of a compensating device is performed for the prevention of abnormal voltage variations caused by a large amount of reactive and nonlinear load. In addition, through the comparison of the pre- and post-application of compensation devices in the actual power system, it is verified that a stable operation of the KSTAR nuclear fusion experimental system can be achieved.

  16. Filter apparatus

    Butterworth, D.J.

    1980-01-01

    This invention relates to liquid filters, precoated by replaceable powders, which are used in the production of ultra pure water required for steam generation of electricity. The filter elements are capable of being installed and removed by remote control so that they can be used in nuclear power reactors. (UK)

  17. Design and implementation of a multiband digital filter using FPGA to extract the ECG signal in the presence of different interference signals.

    Aboutabikh, Kamal; Aboukerdah, Nader

    2015-07-01

    In this paper, we propose a practical way to synthesize and filter an ECG signal in the presence of four types of interference signals: (1) those arising from power networks with a fundamental frequency of 50Hz, (2) those arising from respiration, having a frequency range from 0.05 to 0.5Hz, (3) muscle signals with a frequency of 25Hz, and (4) white noise present within the ECG signal band. This was done by implementing a multiband digital filter (seven bands) of type FIR Multiband Least Squares using a digital programmable device (Cyclone II EP2C70F896C6 FPGA, Altera), which was placed on an education and development board (DE2-70, Terasic). This filter was designed using the VHDL language in the Quartus II 9.1 design environment. The proposed method depends on Direct Digital Frequency Synthesizers (DDFS) designed to synthesize the ECG signal and various interference signals. So that the synthetic ECG specifications would be closer to actual ECG signals after filtering, we designed in a single multiband digital filter instead of using three separate digital filters LPF, HPF, BSF. Thus all interference signals were removed with a single digital filter. The multiband digital filter results were studied using a digital oscilloscope to characterize input and output signals in the presence of differing sinusoidal interference signals and white noise. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Hydrological controls on heterotrophic soil respiration across an agricultural landscape

    Water availability is an important determinant of variation in soil respiration, but a consistent relationship between soil water and the relative flux rate of carbon dioxide across different soil types remains elusive. Using large undisturbed soil columns (N = 12), we evaluated soil water controls...

  19. Contribution of Root Respiration to Soil Respiration in Sugarcane Plantation in Thailand

    Wilaiwan Sornpoon; Sebastien Bonnet; Poonpipope Kasemsap; Savitri Garivait

    2013-01-01

    The understanding on the contribution of root respiration to total soil respiration is still very limited, especially for sugarcane. In this study, trenching experiments in sugarcane plantations were conducted to separate and investigate soil respiration for this crop. The measurements were performed for the whole growing period of 344 days to quantify root respiration. The obtained monitoring data showed that the respiration rate is increasing with the age of the plant, accounting for up to ...

  20. Detection of human papillomavirus among women in Laos: feasibility of using filter paper card and prevalence of high-risk types.

    Phongsavan, Keokedthong; Gustavsson, Inger; Marions, Lena; Phengsavanh, Alongkone; Wahlström, Rolf; Gyllensten, Ulf

    2012-10-01

    Persistent infection with high-risk (HR) human papillomavirus (HPV) is a well-recognized cause of cervical cancer, but little is known about the situation in Laos. The aims of the study were to determine the prevalence of HR-HPV among Lao women and to evaluate the use of a filter paper card (FTA Elute Micro Card) for collection of cervical cells in the humid tropical climate. This is a cross-sectional study including 1922 women from 3 provinces in Laos. During a gynecological examination, cervical cells were collected and applied to the FTA card followed by HPV typing using a real-time polymerase chain reaction (PCR)-based assay. Overall, 213 of the 1922 women were positive for HR-HPV (11%). The most common type was the group HPV33/52/58 (3%), followed by the single type 16 (2%) and the group 18/45 (1%), respectively. Only 11 cards (0.6%) did not contain a sufficient amount of genomic DNA for polymerase chain reaction-based analysis. The prevalence of HR-HPV infections in Laos is similar to other Asian countries, and 40% of the women with an HR-HPV infection will be target of the present HPV vaccines. The FTA card is suitable for collection of cervical cells for HR-HPV typing in tropical conditions. This information is important for planning and establishing primary and secondary prevention of cervical cancer in Laos.

  1. Some arithmetically symmetrical bandpass filters

    Paranasi, P.; Roy, S. C. D.

    1981-01-01

    A combination of the conventional and Matthaei lowpass-bandpass transformations is shown to result in some bandpass filters having very good arithmetic symmetry. The technique presented is applicable to the Butterworth and inverse Chebyshev types of magnitude approximations and the Bessel type of delay approximations. It is not valid, however, for the Chebyshev and elliptic varieties of filters.

  2. Diel hysteresis between soil respiration and soil temperature in a biological soil crust covered desert ecosystem.

    Guan, Chao; Li, Xinrong; Zhang, Peng; Chen, Yongle

    2018-01-01

    Soil respiration induced by biological soil crusts (BSCs) is an important process in the carbon (C) cycle in arid and semi-arid ecosystems, where vascular plants are restricted by the harsh environment, particularly the limited soil moisture. However, the interaction between temperature and soil respiration remains uncertain because of the number of factors that control soil respiration, including temperature and soil moisture, especially in BSC-dominated areas. In this study, the soil respiration in moss-dominated crusts and lichen-dominated crusts was continuously measured using an automated soil respiration system over a one-year period from November 2015 to October 2016 in the Shapotou region of the Tengger Desert, northern China. The results indicated that over daily cycles, the half-hourly soil respiration rates in both types of BSC-covered areas were commonly related to the soil temperature. The observed diel hysteresis between the half-hourly soil respiration rates and soil temperature in the BSC-covered areas was limited by nonlinearity loops with semielliptical shapes, and soil temperature often peaked later than the half-hourly soil respiration rates in the BSC-covered areas. The average lag times between the half-hourly soil respiration rates and soil temperature for both types of BSC-covered areas were two hours over the diel cycles, and they were negatively and linearly related to the volumetric soil water content. Our results highlight the diel hysteresis phenomenon that occurs between soil respiration rates and soil temperatures in BSC-covered areas and the negative response of this phenomenon to soil moisture, which may influence total C budget evaluations. Therefore, the interactive effects of soil temperature and moisture on soil respiration in BSC-covered areas should be considered in global carbon cycle models of desert ecosystems.

  3. Application of the Continuous-Discrete Extended Kalman Filter for Fault Detection in Continuous Glucose Monitors for Type 1 Diabetes

    Mahmoudi, Zeinab; Boiroux, Dimitri; Hagdrup, Morten

    2016-01-01

    The purpose of this study is the online detection of faults and anomalies of a continuous glucose monitor (CGM). We simulated a type 1 diabetes patient using the Medtronic virtual patient model. The model is a system of stochastic differential equations and includes insulin pharmacokinetics...

  4. Studies of significant properties of filter-type self rescuer for its use in underground coal mine in carbon monoxide exposure

    Kumar, A.; Mondal, P.C. [Central Institute of Mining and Fuel Research, Dhanbad (India)

    2007-07-01

    CO is a highly toxic gas; it is the outcome of fire or explosion in underground coal mines. It combines with hemoglobin of coal mine workers and carboxyhemoglobin forms, which reduces the oxygen carrying capacity of blood. A little intake of CO gas, even 0.1% in atmosphere, causes respiratory failure. Filter-type self rescuers (FSR) are a life-saving gas mask breathing apparatus against CO exposure in underground coal mine. The quality of FSR was evaluated in respect of its duration for use, CO conversion by hopcalite, breathing resistance, leak tightness properties, and so on. A scope of improvement is observed in cartridge of self rescuer as well as in the clauses of BIS 9563-1980 in order to increase the duration and improvement in the quality of self rescuers. 12 refs., 2 tabs.

  5. Personalized State-space Modeling of Glucose Dynamics for Type 1 Diabetes Using Continuously Monitored Glucose, Insulin Dose, and Meal Intake: An Extended Kalman Filter Approach.

    Wang, Qian; Molenaar, Peter; Harsh, Saurabh; Freeman, Kenneth; Xie, Jinyu; Gold, Carol; Rovine, Mike; Ulbrecht, Jan

    2014-03-01

    An essential component of any artificial pancreas is on the prediction of blood glucose levels as a function of exogenous and endogenous perturbations such as insulin dose, meal intake, and physical activity and emotional tone under natural living conditions. In this article, we present a new data-driven state-space dynamic model with time-varying coefficients that are used to explicitly quantify the time-varying patient-specific effects of insulin dose and meal intake on blood glucose fluctuations. Using the 3-variate time series of glucose level, insulin dose, and meal intake of an individual type 1 diabetic subject, we apply an extended Kalman filter (EKF) to estimate time-varying coefficients of the patient-specific state-space model. We evaluate our empirical modeling using (1) the FDA-approved UVa/Padova simulator with 30 virtual patients and (2) clinical data of 5 type 1 diabetic patients under natural living conditions. Compared to a forgetting-factor-based recursive ARX model of the same order, the EKF model predictions have higher fit, and significantly better temporal gain and J index and thus are superior in early detection of upward and downward trends in glucose. The EKF based state-space model developed in this article is particularly suitable for model-based state-feedback control designs since the Kalman filter estimates the state variable of the glucose dynamics based on the measured glucose time series. In addition, since the model parameters are estimated in real time, this model is also suitable for adaptive control. © 2014 Diabetes Technology Society.

  6. Quick-change filter cartridge

    Rodgers, John C.; McFarland, Andrew R.; Ortiz, Carlos A.

    1995-01-01

    A quick-change filter cartridge. In sampling systems for measurement of airborne materials, a filter element is introduced into the sampled airstream such that the aerosol constituents are removed and deposited on the filter. Fragile sampling media often require support in order to prevent rupture during sampling, and careful mounting and sealing to prevent misalignment, tearing, or creasing which would allow the sampled air to bypass the filter. Additionally, handling of filter elements may introduce cross-contamination or exposure of operators to toxic materials. Moreover, it is desirable to enable the preloading of filter media into quick-change cartridges in clean laboratory environments, thereby simplifying and expediting the filter-changing process in the field. The quick-change filter cartridge of the present invention permits the application of a variety of filter media in many types of instruments and may also be used in automated systems. The cartridge includes a base through which a vacuum can be applied to draw air through the filter medium which is located on a porous filter support and held there by means of a cap which forms an airtight seal with the base. The base is also adapted for receiving absorbing media so that both particulates and gas-phase samples may be trapped for investigation, the latter downstream of the aerosol filter.

  7. Filter systems

    Vanin, V.R.

    1990-01-01

    The multidetector systems for high resolution gamma spectroscopy are presented. The observable parameters for identifying nuclides produced simultaneously in the reaction are analysed discussing the efficiency of filter systems. (M.C.K.)

  8. Diurnal variation in soil respiration under different land uses on Taihang Mountain, North China

    Liu, Xiuping; Zhang, Wanjun; Zhang, Bin; Yang, Qihong; Chang, Jianguo; Hou, Ke

    2016-01-01

    The aim of this paper is to evaluate the diurnal variation in soil respiration under different land use types on Taihang Mountain, North China, and to understand its response to environmental factors (e.g., soil temperature and moisture) and forest management. Diurnal variations in soil respiration from plantations (Robinia pseudoacacia, Punica granatum, and Ziziphus jujuba), naturally regenerated forests (Vitex negundo var. heterophylla), grasslands (Bothriochloa ischaemum), and farmlands (winter wheat/summer maize) were measured using an LI-8100 automated soil CO2 flux system from May 2012 to April 2013. The results indicated that land use type had a significant effect on the diurnal variation of soil respiration. The diurnal soil respiration from farmlands was highest, followed by Ziziphus jujube, R. pseudoacacia, P. granatum, the lower soil CO2 efflux was found from B. ischaemum and V. negundo var. heterophylla. The diurnal soil respiration across different land use types was significantly affected by soil temperature and moisture, and their interaction. Precipitation-stimulated soil respiration increased more in soil with low water content and less in soil with high water content. The lower diurnal soil respiration from naturally regenerated forests suggests that naturally regenerated vegetation is the optimal vegetation type for reducing global warming.

  9. Improved Detection of Human Respiration Using Data Fusion Basedon a Multistatic UWB Radar

    Hao Lv

    2016-09-01

    Full Text Available This paper investigated the feasibility for improved detection of human respiration using data fusion based on a multistatic ultra-wideband (UWB radar. UWB-radar-based respiration detection is an emerging technology that has great promise in practice. It can be applied to remotely sense the presence of a human target for through-wall surveillance, post-earthquake search and rescue, etc. In these applications, a human target’s position and posture are not known a priori. Uncertainty of the two factors results in a body orientation issue of UWB radar, namely the human target’s thorax is not always facing the radar. Thus, the radial component of the thorax motion due to respiration decreases and the respiratory motion response contained in UWB radar echoes is too weak to be detected. To cope with the issue, this paper used multisensory information provided by the multistatic UWB radar, which took the form of impulse radios and comprised one transmitting and four separated receiving antennas. An adaptive Kalman filtering algorithm was then designed to fuse the UWB echo data from all the receiving channels to detect the respiratory-motion response contained in those data. In the experiment, a volunteer’s respiration was correctly detected when he curled upon a camp bed behind a brick wall. Under the same scenario, the volunteer’s respiration was detected based on the radar’s single transmitting-receiving channels without data fusion using conventional algorithm, such as adaptive line enhancer and single-channel Kalman filtering. Moreover, performance of the data fusion algorithm was experimentally investigated with different channel combinations and antenna deployments. The experimental results show that the body orientation issue for human respiration detection via UWB radar can be dealt well with the multistatic UWB radar and the Kalman-filter-based data fusion, which can be applied to improve performance of UWB radar in real applications.

  10. Separating the effect of respiration from the heart rate variability for cases of constant harmonic breathing

    Kircher Michael

    2015-09-01

    Full Text Available Heart Rate Variability studies are a known measure for the autonomous control of the heart rate. In special situations, its interpretation can be ambiguous, since the respiration has a major influence on the heart rate variability. For this reason it has often been proposed to measure Heart Rate Variability, while the subjects are breathing at a constant respiration rate. That way the spectral influence of the respiration is known. In this work we propose to remove this constant respiratory influence from the heart rate and the Heart Rate Variability parameters to gain respiration free autonomous controlled heart rate signal. The spectral respiratory component in the heart rate signal is detected and characterized. Subsequently the respiratory effect on Heart Rate Variability is removed using spectral filtering approaches, such as the Notch filter or the Raised Cosine filter. As a result new decoupled Heart Variability parameters are gained, which could lead to new additional interpretations of the autonomous control of the heart rate.

  11. Management effects on European cropland respiration

    Eugster, Werner; Moffat, Antje M.; Ceschia, Eric

    2010-01-01

    Increases in respiration rates following management activities in croplands are considered a relevant anthropogenic source of CO2. In this paper, we quantify the impact of management events on cropland respiration fluxes of CO2 as they occur under current climate and management conditions. Our....... This allowed us to address the question of how management activities influence ecosystem respiration. This was done by comparing respiration fluxes during 7, 14, and 28 days after the management with those observed during the matching time period before management. Median increases in respiration ranged from...... than management alone are also important at a given site. Temperature is the climatic factor that showed best correlation with site-specific respiration fluxes. Therefore, the effect of temperature changes between the time periods before and after management were taken into account for a subset of 13...

  12. Effects of respirator use on worker performance

    Cardarelli, R. [Yankee Atomic Electric Co., Bolton, MA (United States)

    1995-03-01

    In 1993, EPRI funded Yankee Atomic Electric Company to examine the effects of respirator use on worker efficiency. Phase I of Yankee`s effort was to develop a study design to determine respirator effects. Given success in Phase I, a larger population will be tested to determine if a stasitically significant respirator effect on performance can be measured. This paper summarizes the 1993 EPRI/Yankee Respirator Effects of Pilot Study, and describes the study design for the 1994 EPRI/Yankee Respirator Study to be conducted at the Oyster Creek Nuclear Power Plant. Also described is a summary of respirator effect studies that have been conducted during the last ten (10) years.

  13. Progress towards the use of disposable filters

    Macphail, I.

    1979-08-01

    Thermally degradable materials have been evaluated for service in HEPA filter units used to filter gases from active plants. The motivation was to reduce the bulk storage problems of contaminated filters by thermal decomposition to gaseous products and a solid residue substantially comprised of the filtered particulates. It is shown that while there are no commercially available alternatives to the glass fibre used in the filter medium, it would be feasible to manufacture the filter case and spacers from materials which could be incinerated. Operating temperatures, costs and the type of residues for disposal are discussed for filter case materials. (U.K.)

  14. Risk Sensitive Filtering with Poisson Process Observations

    Malcolm, W. P.; James, M. R.; Elliott, R. J.

    2000-01-01

    In this paper we consider risk sensitive filtering for Poisson process observations. Risk sensitive filtering is a type of robust filtering which offers performance benefits in the presence of uncertainties. We derive a risk sensitive filter for a stochastic system where the signal variable has dynamics described by a diffusion equation and determines the rate function for an observation process. The filtering equations are stochastic integral equations. Computer simulations are presented to demonstrate the performance gain for the risk sensitive filter compared with the risk neutral filter

  15. The Successful Diagnosis and Typing of Systemic Amyloidosis Using A Microwave-Assisted Filter-Aided Fast Sample Preparation Method and LC/MS/MS Analysis.

    Weiyi Sun

    Full Text Available Laser microdissection followed by mass spectrometry has been successfully used for amyloid typing. However, sample contamination can interfere with proteomic analysis, and overnight digestion limits the analytical throughput. Moreover, current quantitative analysis methods are based on the spectrum count, which ignores differences in protein length and may lead to misdiagnoses. Here, we developed a microwave-assisted filter-aided sample preparation (maFASP method that can efficiently remove contaminants with a 10-kDa cutoff ultrafiltration unit and can accelerate the digestion process with the assistance of a microwave. Additionally, two parameters (P- and D-scores based on the exponentially modified protein abundance index were developed to define the existence of amyloid deposits and those causative proteins with the greatest abundance. Using our protocol, twenty cases of systemic amyloidosis that were well-typed according to clinical diagnostic standards (training group and another twenty-four cases without subtype diagnoses (validation group were analyzed. Using this approach, sample preparation could be completed within four hours. We successfully subtyped 100% of the cases in the training group, and the diagnostic success rate in the validation group was 91.7%. This maFASP-aided proteomic protocol represents an efficient approach for amyloid diagnosis and subtyping, particularly for serum-contaminated samples.

  16. The Successful Diagnosis and Typing of Systemic Amyloidosis Using A Microwave-Assisted Filter-Aided Fast Sample Preparation Method and LC/MS/MS Analysis.

    Sun, Weiyi; Sun, Jian; Zou, Lili; Shen, Kaini; Zhong, Dingrong; Zhou, Daobin; Sun, Wei; Li, Jian

    2015-01-01

    Laser microdissection followed by mass spectrometry has been successfully used for amyloid typing. However, sample contamination can interfere with proteomic analysis, and overnight digestion limits the analytical throughput. Moreover, current quantitative analysis methods are based on the spectrum count, which ignores differences in protein length and may lead to misdiagnoses. Here, we developed a microwave-assisted filter-aided sample preparation (maFASP) method that can efficiently remove contaminants with a 10-kDa cutoff ultrafiltration unit and can accelerate the digestion process with the assistance of a microwave. Additionally, two parameters (P- and D-scores) based on the exponentially modified protein abundance index were developed to define the existence of amyloid deposits and those causative proteins with the greatest abundance. Using our protocol, twenty cases of systemic amyloidosis that were well-typed according to clinical diagnostic standards (training group) and another twenty-four cases without subtype diagnoses (validation group) were analyzed. Using this approach, sample preparation could be completed within four hours. We successfully subtyped 100% of the cases in the training group, and the diagnostic success rate in the validation group was 91.7%. This maFASP-aided proteomic protocol represents an efficient approach for amyloid diagnosis and subtyping, particularly for serum-contaminated samples.

  17. HF filter design and computer simulation

    Rhea, Randall W

    1994-01-01

    A book for engineers who design and build filters of all types, including lumped element, coaxial, helical, dielectric resonator, stripline and microstrip types. A thorough review of classic and modern filter design techniques, containing extensive practical design information of passband characteristics, topologies and transformations, component effects and matching. An excellent text for the design and construction of microstrip filters.

  18. Cardiac, skeletal, and smooth muscle mitochondrial respiration: are all mitochondria created equal?

    Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I; Trinity, Joel D; Hyngstrom, John R; Garten, Ryan S; Diakos, Nikolaos A; Ives, Stephen J; Dela, Flemming; Larsen, Steen; Drakos, Stavros; Richardson, Russell S

    2014-08-01

    Unlike cardiac and skeletal muscle, little is known about vascular smooth muscle mitochondrial respiration. Therefore, the present study examined mitochondrial respiratory rates in smooth muscle of healthy human feed arteries and compared with that of healthy cardiac and skeletal muscles. Cardiac, skeletal, and smooth muscles were harvested from a total of 22 subjects (53 ± 6 yr), and mitochondrial respiration was assessed in permeabilized fibers. Complex I + II, state 3 respiration, an index of oxidative phosphorylation capacity, fell progressively from cardiac to skeletal to smooth muscles (54 ± 1, 39 ± 4, and 15 ± 1 pmol·s(-1)·mg(-1), P respiration rates were normalized by CS (respiration per mitochondrial content), oxidative phosphorylation capacity was no longer different between the three muscle types. Interestingly, complex I state 2 normalized for CS activity, an index of nonphosphorylating respiration per mitochondrial content, increased progressively from cardiac to skeletal to smooth muscles, such that the respiratory control ratio, state 3/state 2 respiration, fell progressively from cardiac to skeletal to smooth muscles (5.3 ± 0.7, 3.2 ± 0.4, and 1.6 ± 0.3 pmol·s(-1)·mg(-1), P respiration highlight the existence of intrinsic functional differences between these muscle mitochondria. This likely influences the efficiency of oxidative phosphorylation and could potentially alter ROS production.

  19. Respirators: Supervisors Self-Study #43442

    Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-04-20

    This course, Respirators: Supervisors Self-Study (#43442), addresses training requirements for supervisors of respirator wearers as specified by the American National Standard Institute (ANSI) Standard for Respiratory Protection, ANSI Z88.2, and as incorporated by reference in the Department of Energy (DOE) Worker Health and Safety Rule, 10 Code of Federal Regulations (CFR) 851. This course also presents the responsibilities of supervisors of respirator wearers at Los Alamos National Laboratory (LANL).

  20. From Microwave Filter to Digital Filter and Back Again

    Dalby, Arne Brejning

    1989-01-01

    A new very simple state variable flow graph representation for interdigital transmission line bandpass filters is presented, which has led to two important results: 1) A new type of digital filter with properties, that surpass the properties of most other (all pole) digital filtertypes. 2) The st...

  1. US Department of Transportation (DOT) Spec 7A Type A evaluation document: Spec 17C 55-gal steel drum with RWMC/SWEPP drum venting system carbon filter assembly

    Edling, D.A.

    1986-01-01

    As part of MRC-Mound's responsibility to coordinate DOE Spec 7A Type A Packaging testing, evaluation, and utilization, this document evaluates per 49CFR 173.415(a) the SWEPP packaging system: DOT Spec 17C steel drums - 30, 55 and 83-gal; High Density Polyethylene (HDPE) liners; and SWEPP DVS Filter Assemblies (two configurations) as a US DOT Spec 7A Type A packaging. A variety of Type A performance testing was done on: DOT Spec 17C 55-gal steel drums; DOT Spec 17C 55-gal steel drums with HDPE liners; and DOT Spec 17C 55-gal steel drums with ''Nucfil'' filters as part of MRC-Mound's Type A Packaging Evaluation Program funded by DOE/HQ, DP-4, Security Evaluations. The subject SWEPP packaging incorporates modifications to the ''Nucfil'' filter and installation assembly previously tested in conjunction with the Spec 17C 55-gal drums. Thus, additional testing was required on the new filter installation in order to evaluate the entire packaging system. This document presents the test data to demonstrate the SWEPP packaging system's performance against the DOT 7A Type A requirements

  2. Cisplatin cytotoxicity is dependent on mitochondrial respiration in Saccharomyces cerevisiae

    Santhipriya Inapurapu

    2017-01-01

    Full Text Available Objective(s: To understand the role of mitochondrial respiration in cisplatin sensitivity, we have employed wild-type and mitochondrial DNA depleted Rho0 yeast cells. Materials and Methods: Wild type and Rho0 yeast cultured in fermentable and non-fermentable sugar containing media, were studied for their sensitivity against cisplatin by monitoring growth curves, oxygen consumption, pH changes in cytosol/mitochondrial compartments, reactive oxygen species production and respiratory control ratio. Results: Wild-type yeast grown on glycerol exhibited heightened sensitivity to cisplatin than yeast grown on glucose. Cisplatin (100 μM, although significantly reduced the growth of wild- type cells, only slightly altered the growth rate of Rho0 cells. Cisplatin treatment decreased both pHcyt and pHmit to a similar extent without affecting the pH difference. Cisplatin dose-dependently increased the oxidative stress in wild-type, but not in respiration-deficient Rho0 strain. Cisplatin decreased the respiratory control ratio. Conclusion: These results suggest that cisplatin toxicity is influenced by the respiratory capacity of the cells and the intracellular oxidative burden. Although cisplatin per se slightly decreased the respiration of yeast cells grown in glucose, it did not disturb the mitochondrial chemiosmotic gradient.

  3. Relationships between Personal Measurements of 'Total' Dust, Respirable, Thoracic, and Inhalable Aerosol Fractions in the Cement Production Industry.

    Notø, Hilde P; Nordby, Karl-Christian; Eduard, Wijnand

    2016-05-01

    The aims of this study were to examine the relationships and establish conversion factors between 'total' dust, respirable, thoracic, and inhalable aerosol fractions measured by parallel personal sampling on workers from the production departments of cement plants. 'Total' dust in this study refers to aerosol sampled by the closed face 37-mm Millipore filter cassette. Side-by-side personal measurements of 'total' dust and respirable, thoracic, and inhalable aerosol fractions were performed on workers in 17 European and Turkish cement plants. Simple linear and mixed model regressions were used to model the associations between the samplers. The total number of personal samples collected on 141 workers was 512. Of these 8.4% were excluded leaving 469 for statistical analysis. The different aerosol fractions contained from 90 to 130 measurements and-side-by side measurements of all four aerosol fractions were collected on 72 workers.The median ratios between observed results of the respirable, 'total' dust, and inhalable fractions relative to the thoracic aerosol fractions were 0.51, 2.4, and 5.9 respectively. The ratios between the samplers were not constant over the measured concentration range and were best described by regression models. Job type, position of samplers on left or right shoulder and plant had no substantial effect on the ratios. The ratios between aerosol fractions changed with different air concentrations. Conversion models for estimation of the fractions were established. These models explained a high proportion of the variance (74-91%) indicating that they are useful for the estimation of concentrations based on measurements of a different aerosol fraction. The calculated uncertainties at most observed concentrations were below 30% which is acceptable for comparison with limit values (EN 482, 2012). The cement industry will therefore be able to predict the health related aerosol fractions from their former or future measurements of one of the

  4. Endotoxin and dust at respirable and nonrespirable particle sizes are not consistent between cage- and floor-housed poultry operations.

    Kirychuk, Shelley P; Reynolds, Stephen J; Koehncke, Niels K; Lawson, Joshua; Willson, Philip; Senthilselvan, Ambikaipakan; Marciniuk, Darcy; Classen, Henry L; Crowe, Trever; Just, Natasha; Schneberger, David; Dosman, James A

    2010-10-01

    Individuals engaged in work in intensive animal houses experience some of the highest rates of occupationally related respiratory symptoms. Organic dust and in particular endotoxin has been most closely associated with respiratory symptoms and lung function changes in workers. It has previously been shown that for intensive poultry operations, type of poultry housing [cage-housed (CH) versus floor-housed (FH)] can influence the levels of environmental contaminants. The goal of the study was to determine the differences in endotoxin and dust levels at different size fractions between CH and FH poultry operations. Fifteen CH and 15 FH poultry operations were sampled for stationary measurements (area) of dust and associated endotoxin. Fractioned samples were collected utilizing Marple cascade impactors. Gravimetric and endotoxin analysis were conducted on each of the filters. When assessed by individual Marple stage, there was significantly greater airborne endotoxin concentration (endotoxin units per cubic meter) in the size fraction >9.8 μm for the FH operations whereas at the size fraction 1.6-3.5 μm, the CH operations had significantly greater airborne endotoxin concentration than the FH operations. Endotoxin concentration in the dust mass (endotoxin units per milligram) was significantly greater in the CH operations as compared to the FH operations for all size fractions >1.6 μm. As such, endotoxin in the respirable fraction accounted for 24% of the total endotoxin in the CH operations whereas it accounted for only 11% in the FH operations. There was significantly more dust in all size fractions in the FH operations as compared to the CH poultry operations. There is more endotoxin in the presence of significantly lower dust levels in the respirable particle size fractions in CH poultry operations as compared to the FH poultry operations. This difference in respirable endotoxin may be important in relation to the differential respiratory response experienced by

  5. Deep Ultraviolet Macroporous Silicon Filters, Phase I

    National Aeronautics and Space Administration — This SBIR Phase I proposal describes a novel method to make deep and far UV optical filters from macroporous silicon. This type of filter consists of an array of...

  6. [Effects of Tillage on Soil Respiration and Root Respiration Under Rain-Fed Summer Corn Field].

    Lu, Xing-li; Liao, Yun-cheng

    2015-06-01

    To explore the effects of different tillage systems on soil respiration and root respiration under rain-fed condition. Based on a short-term experiment, this paper investigated soil respiration in summer corn growth season under four tillage treatments including subsoiling tillage (ST), no tillage (NT), rotary tillage (RT) and moldboard plow tillage (CT). The contribution of root respiration using root exclusion method was also discussed. The results showed that soil respiration rate presented a single peak trend under four tillage methods during the summer corn growing season, and the maximum value was recorded at the heading stage. The trends of soil respiration were as follows: heading stage > flowering stage > grain filling stage > maturity stage > jointing stage > seedling stage. The trends of soil respiration under different tillage systems were as follows: CT > ST > RT > NT. There was a significant correlation between soil respiration rate and soil temperatures (P soil respiration using exponential function equation. However, there was no significant correlation between soil respiration rate and soil moisture. Root respiration accounted for 45.13%-56.86% of the proportion of soil respiratio n with the mean value 51.72% during the summer corn growing season under different tillage systems. Therefore, root exclusion method could be used to study the contribution of crop growth to carbon emission, to compare effects of different tillage systems on the contribution of root respiration provides the bases for selecting the measures to slow down the decomposition of soil carbon.

  7. Soil Respiration of Three Mangrove Forests on Sanibel Island, Florida

    Cartwright, F.; Bovard, B. D.

    2011-12-01

    Carbon cycling studies conducted in mangrove forests have typically focused on aboveground processes. Our understanding of carbon storage in these systems is therefore limited by the lack information on belowground processes such as fine root production and soil respiration. To our knowledge there exist no studies investigating temporal patterns in and environmental controls on soil respiration in multiple types of mangrove ecosystems concurrently. This study is part of a larger study on carbon storage in three mangrove forests on Sanibel Island, Florida. Here we report on eight months of soil respiration data within these forests that will ultimately be incorporated into an annual carbon budget for each habitat type. Soil respiration was monitored in the following three mangrove habitat types: a fringe mangrove forest dominated by Rhizophora mangle, a basin mangrove forest dominated by Avicennia germinans, and a higher elevation forest comprised of a mix of Avicennia germinans and Laguncularia racemosa, and non-woody salt marsh species. Beginning in June of 2010, we measured soil emissions of carbon dioxide at 5 random locations within three-100 m2 plots within each habitat type. Sampling was performed at monthly intervals and conducted over the course of three days. For each day, one plot from each habitat type was measured. In addition to soil respiration, soil temperature, salinity and gravimetric moisture content were also measured. Our data indicate the Black mangrove forest, dominated by Avicennia germinans, experiences the highest rates of soil respiration with a mean rate of 4.61 ± 0.60 μmol CO2 m-2 s-1. The mixed mangrove and salt marsh habitat has the lowest soil carbon emission rates with a mean of 2.78 ± 0.40 μmol CO2 m-2 s-1. Soil carbon effluxes appear to peak in the early part of the wet season around May to June and are lower and relatively constant the remainder of the year. Our data also suggest there are important but brief periods where

  8. Mobile filters in nuclear engineering

    Meuter, R.

    1979-01-01

    The need for filters with high efficiencies which may be used at any place originated in nuclear power plants. Filters of this type, called Filtermobil, have been developed by Sulzer. They have been used successfully in nuclear plants for several years. (orig.) [de

  9. Performance behavior of prediction filters for respiratory motion compensation in radiotherapy

    Jöhl Alexander

    2017-09-01

    Full Text Available Introduction: In radiotherapy, tumors may move due to the patient’s respiration, which decreases treatment accuracy. Some motion mitigation methods require measuring the tumor position during treatment. Current available sensors often suffer from time delays, which degrade the motion mitigation performance. However, the tumor motion is often periodic and continuous, which allows predicting the motion ahead. Method and Materials: A couch tracking system was simulated in MATLAB and five prediction filters selected from literature were implemented and tested on 51 respiration signals (median length: 103 s. The five filters were the linear filter (LF, the local regression (LOESS, the neural network (NN, the support vector regression (SVR, and the wavelet least mean squares (wLMS. The time delay to compensate was 320 ms. The normalized root mean square error (nRMSE was calculated for all prediction filters and respiration signals. The correlation coefficients between the nRMSE of the prediction filters were computed. Results: The prediction filters were grouped into a low and a high nRMSE group. The low nRMSE group consisted of the LF, the NN, and the wLMS with a median nRMSE of 0.14, 0.15, and 0.14, respectively. The high nRMSE group consisted of the LOESS and the SVR with both a median nRMSE of 0.34. The correlations between the low nRMSE filters were above 0.87 and between the high nRMSE filters it was 0.64. Conclusion: The low nRMSE prediction filters not only have similar median nRMSEs but also similar nRMSEs for the same respiration signals as the high correlation shows. Therefore, good prediction filters perform similarly for identical respiration patterns, which might indicate a minimally achievable nRMSE for a given respiration pattern.

  10. Generalised Filtering

    Karl Friston

    2010-01-01

    Full Text Available We describe a Bayesian filtering scheme for nonlinear state-space models in continuous time. This scheme is called Generalised Filtering and furnishes posterior (conditional densities on hidden states and unknown parameters generating observed data. Crucially, the scheme operates online, assimilating data to optimize the conditional density on time-varying states and time-invariant parameters. In contrast to Kalman and Particle smoothing, Generalised Filtering does not require a backwards pass. In contrast to variational schemes, it does not assume conditional independence between the states and parameters. Generalised Filtering optimises the conditional density with respect to a free-energy bound on the model's log-evidence. This optimisation uses the generalised motion of hidden states and parameters, under the prior assumption that the motion of the parameters is small. We describe the scheme, present comparative evaluations with a fixed-form variational version, and conclude with an illustrative application to a nonlinear state-space model of brain imaging time-series.

  11. Filter This

    Audrey Barbakoff

    2011-03-01

    Full Text Available In the Library with the Lead Pipe welcomes Audrey Barbakoff, a librarian at the Milwaukee Public Library, and Ahniwa Ferrari, Virtual Experience Manager at the Pierce County Library System in Washington, for a point-counterpoint piece on filtering in libraries. The opinions expressed here are those of the authors, and are not endorsed by their employers. [...

  12. Adaptive filtering and change detection

    Gustafsson, Fredrik

    2003-01-01

    Adaptive filtering is a classical branch of digital signal processing (DSP). Industrial interest in adaptive filtering grows continuously with the increase in computer performance that allows ever more conplex algorithms to be run in real-time. Change detection is a type of adaptive filtering for non-stationary signals and is also the basic tool in fault detection and diagnosis. Often considered as separate subjects Adaptive Filtering and Change Detection bridges a gap in the literature with a unified treatment of these areas, emphasizing that change detection is a natural extensi

  13. Load compensation for single phase system using series active filter

    user

    Keywords: Active power filter (APF), current source type of harmonic load ... Single phase active filters could attract less attention than three phase due to its low ..... Generalised single-phase p-q theory for active power filtering: simulation and.

  14. OPTIMIZATION OF ADVANCED FILTER SYSTEMS

    R.A. Newby; G.J. Bruck; M.A. Alvin; T.E. Lippert

    1998-04-30

    Reliable, maintainable and cost effective hot gas particulate filter technology is critical to the successful commercialization of advanced, coal-fired power generation technologies, such as IGCC and PFBC. In pilot plant testing, the operating reliability of hot gas particulate filters have been periodically compromised by process issues, such as process upsets and difficult ash cake behavior (ash bridging and sintering), and by design issues, such as cantilevered filter elements damaged by ash bridging, or excessively close packing of filtering surfaces resulting in unacceptable pressure drop or filtering surface plugging. This test experience has focused the issues and has helped to define advanced hot gas filter design concepts that offer higher reliability. Westinghouse has identified two advanced ceramic barrier filter concepts that are configured to minimize the possibility of ash bridge formation and to be robust against ash bridges should they occur. The ''inverted candle filter system'' uses arrays of thin-walled, ceramic candle-type filter elements with inside-surface filtering, and contains the filter elements in metal enclosures for complete separation from ash bridges. The ''sheet filter system'' uses ceramic, flat plate filter elements supported from vertical pipe-header arrays that provide geometry that avoids the buildup of ash bridges and allows free fall of the back-pulse released filter cake. The Optimization of Advanced Filter Systems program is being conducted to evaluate these two advanced designs and to ultimately demonstrate one of the concepts in pilot scale. In the Base Contract program, the subject of this report, Westinghouse has developed conceptual designs of the two advanced ceramic barrier filter systems to assess their performance, availability and cost potential, and to identify technical issues that may hinder the commercialization of the technologies. A plan for the Option I, bench

  15. Economic analysis of implementing respirator program or ventilation system in a manufacturing environment

    Saidi-Mehrabab, M.

    2000-01-01

    The techniques and methods of developing cost models for respirators are discussed. Models are developed and implemented in this study for nineteen types of respirators in two major classes (air-purifying and supplied-air) and one L EV system. One respirator model is selected for detailed discussion from among the twenty models. The technical cost method is used in constructing the cost models for each of the respirators and the L EV system. In this methodology, the costs of purchasing and using a typical respirator or L EV system are divided into two categories, variable costs and fixed costs. Variable costs consists of the cost of replaceable components and probabilistic mortality cost. Fixed cost is the annualized capital requirement plus interest cost. The criteria for estimating some of the cost elements are based on existing equations in the literature, engineering judgement and manufacturer-provided information. A technical cost model results from the integration of this information into a computerized framework. The cost models for discussion are presented in the order of increasing computational complexity. Through the economic analysis, the lowest cost type in each class of respirator is determined. The determination criteria are based on the minimum total annual cost and highest benefit cost ratio. The selected lowest cost respirators are compared with the L EV system from the economic standpoint to reveal the cost optimal alternative

  16. Reconfigurable Mixed Mode Universal Filter

    Neelofer Afzal

    2014-01-01

    Full Text Available This paper presents a novel mixed mode universal filter configuration capable of working in voltage and transimpedance mode. The proposed single filter configuration can be reconfigured digitally to realize all the five second order filter functions (types at single output port. Other salient features of proposed configuration include independently programmable filter parameters, full cascadability, and low sensitivity figure. However, all these features are provided at the cost of quite large number of active elements. It needs three digitally programmable current feedback amplifiers and three digitally programmable current conveyors. Use of six active elements is justified by introducing three additional reduced hardware mixed mode universal filter configurations and its comparison with reported filters.

  17. Evaluation of residential furnace filters

    Bowser, D. [Bowser Technical Inc. (Canada)

    1999-07-01

    Various filters rotated through six houses in southern Ontario during the heating season were evaluated for their filtration efficiency, including their ability to trap respirable particulate matter. Particulate levels were continuously monitored in the outside air, before and after the filter in the ducting system; also in the air in two rooms in each house. Results show that the filters performed according to their respective efficiency ratings. The integrated breathing zone exposure reading were not considered as significant as the reductions in the ducting system, dur to the fact that the integrated breathing zone exposure reflects both dust generation and dust removal mechanisms. Electronic air filters were found to produce ozone inside the home when the air-handling system was in operation. There was no evidence of any particular relationship between cleanliness and ozone production. Indoor ozone levels were always lower than outdoor levels. Continuous blower operation was found to improve filtration efficiency , however, it could result in an increase of about $250 in annual energy expenses. Bypass filters recorded significantly higher electrical energy consumption than full-flow systems. Continuous low-speed air handler fan operation appeared to be the most effective strategy. Portable air cleaners were shown to be highly effective in removing particulates in a single room. Removing footwear on entering the house, keeping major dust generators out of the house, frequent vacuuming, improving the air tightness of the house, and installing an air intake filter on the air supply may all be all be helpful in controlling exposure to particulates. 21 refs., 8 tabs., 32 figs.

  18. Replacement of fluid-filter elements without interruption of flow

    Kotler, R. A.; Ward, J. B.

    1969-01-01

    Gatling-type filter assembly, preloaded with several filter elements enables filter replacement without breaking into the operative fluid system. When the filter element becomes contaminated, a unit inner subassembly is rotated 60 degrees to position a clean filter in the line.

  19. Energy savings in dust collector plants of bag house filter type. Phase 1 - Literature study; Energieffektivisering av anlaeggningar foer stoftrening med slangfilter. Etapp 1-Litteraturstudie

    Eriksson, Lars; Wikman, Karin; Berg, Magnus [AaF-Energi and Miljoe AB, Stockholm (Sweden)

    2004-01-01

    The largest energy demands in connection with the operation of bag house filters are the electric energy consumption for the fans, securing the flow of flue gas through the filter, and the electric energy consumption when producing the pressurized air (compressors or high pressure fans). Considering the significantly increased fan work when having a non-optimised cleaning of the filters, it seems justified to investigate the possibilities to minimise the unnecessary pressure drop. There is also a saving potential in the filter cleaning process, which otherwise may cost an unacceptable amount of pressurized air or other energy. The main purpose of this work is to develop methods to optimize the operation of bag house filters, which is started up with this report containing a follow-up of what has been done in Denmark and a confirmation of the technology status. In the next step, a case study where two-three plants are examined more in detail is suggested followed by a potential study to estimate the total energy saving potential in Sweden. Dust precipitation with bag house filters is basically a rather simple technique, which has existed in flue gas cleaning for about 50 years. From the literature study it can be established that there has been no revolutionary development in the field, but there are some work being done mainly to introduce new filter material but also to optimise the use of bag house filters with new computer based control systems. The largest potential of energy saving prevails if the filter from the beginning is overloaded, which usually is the case. The reason for overload may be a too large volume flow in relation to the filter area, that the dust has penetrated and blocked the filter, a defective filter cleaning process or that wrong filter material has been chosen. In Denmark a study has been made with the purpose to investigate the possibilities to optimise the energy consumption for bag house filters. For the three plants studied, an

  20. Elemental Concentration of Inhalable and Respirable Particulate ...

    20537 and respirable foam for I.O.M sampler. The elemental composition (Co, Ni, Zn, Cu, Fe, Pb, Cr, Mn and Cd) were analyzed by using Atomic Absorption Spectrophotometric (AAS). The data generated were subjected to descriptive analysis. In inhalable fraction,the enrichment factor ranged from 1-73.3 while in respirable ...

  1. Respirators: APR Issuer Self Study 33461

    Chochoms, Michael [Los Alamos National Laboratory

    2016-07-13

    Respirators: APR Issuer Self-Study (course 33461) is designed to introduce and familiarize employees selected as air-purifying respirator (APR) issuers at Los Alamos National Laboratory (LANL) with the responsibilities, limitations, procedures, and resources for issuing APRs at LANL. The goal is to enable these issuers to consistently provide proper, functioning APRs to authorized users

  2. Soil fauna communities and microbial respiration in high Arctic tundra soils at Zackenberg, Northeast Greenland

    Sørensen, Louise I.; Holmstrup, Martin; Maraldo, Kristine

    2006-01-01

    The soil fauna communities were described for three dominant vegetation types in a high arctic site at Zackenberg, Northeast Greenland. Soil samples were extracted to quantify the densities of mites, collembolans, enchytraeids, diptera larvae, nematodes and protozoa. Rates of microbial respiration...... densities (naked amoeba and heterotrophic flagellates) were equal. Respiration rate of unamended soil was similar in soil from the three plots. However, a higher respiration rate increase in carbon + nutrient amended soil and the higher densities of soil fauna (with the exception of mites and protozoa...

  3. A Disease Mutation Causing Episodic Ataxia Type I in the S1 Links Directly to the Voltage Sensor and the Selectivity Filter in Kv Channels.

    Petitjean, Dimitri; Kalstrup, Tanja; Zhao, Juan; Blunck, Rikard

    2015-09-02

    The mutation F184C in Kv1.1 leads to development of episodic ataxia type I (EA1). Although the mutation has been said to alter activation kinetics and to lower expression, we show here that the underlying molecular mechanisms may be more complex. Although F184 is positioned in the "peripheral" S1 helix, it occupies a central position in the 3D fold. We show in cut-open oocyte voltage-clamp recordings of gating and ionic currents of the Shaker Kv channel expressed in Xenopus oocytes that F184 not only interacts directly with the gating charges of the S4, but also creates a functional link to the selectivity filter of the neighboring subunit. This link leads to impaired fast and slow inactivation. The effect on fast inactivation is of an allosteric nature considering that fast inactivation is caused by a linked cytosolic ball peptide. The extensive effects of F184C provide a new mechanism underlying EA. Episodic ataxia (EA) is an inherited disease that leads to occasional loss of motor control in combination with variable other symptoms such as vertigo or migraine. EA type I (EA1), studied here, is caused by mutations in a voltage-gated potassium channel that contributes to the generation of electrical signals in the brain. The mechanism by which mutations in voltage-gated potassium channels lead to EA is still unknown and there is no consistent pharmacological treatment. By studying in detail one disease-causing mutation in Kv1.1, we describe a novel molecular mechanism distinct from mechanisms described previously. This mechanism contributes to the understanding of potassium channel function in general and might lead to a better understanding of how EA develops. Copyright © 2015 the authors 0270-6474/15/3512198-09$15.00/0.

  4. Matching sampler penetration curves to definitions of respirable fraction

    Mercer, T.T.

    1977-01-01

    A formal definition of 'respirable fraction' (the probability that a particle of a given size will deposit in the alveolar regions of the lung if inhaled) is useful only if there is a method of sorting out airborne contamination approximately in accordance with the definition. The matching of the definitions adopted by different organizations to the penetration curves of various types of sample is discussed. (author)

  5. The importance of in vitro diagnostics in respiration allergy

    Wever, A.M.J.

    1987-01-01

    Out of the 4 types of allergic reactions, in respiration allergy the anaphylactic reaction caused by IgE antibodies is the most important. Determination of IgE with radioimmunoassay: the radio-allergo-sorbent test (Rast) and the Phadiatop (pharmacie-differential atopy test) was investigated in 248 patients with pulmonal complaints. Phadiatop can be used as a screening test and for a better application of the specific Rast-diagnostic. 1 table

  6. 42 CFR 84.1155 - Filters used with canisters and cartridges; location; replacement.

    2010-10-01

    ...; location; replacement. 84.1155 Section 84.1155 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH... Efficiency Respirators and Combination Gas Masks § 84.1155 Filters used with canisters and cartridges; location; replacement. (a) Particulate matter filters used in conjunction with a canister or cartridge...

  7. Soil respiration and organic carbon dynamics with grassland conversions to woodlands in temperate china.

    Wei Wang

    Full Text Available Soils are the largest terrestrial carbon store and soil respiration is the second-largest flux in ecosystem carbon cycling. Across China's temperate region, climatic changes and human activities have frequently caused the transformation of grasslands to woodlands. However, the effect of this transition on soil respiration and soil organic carbon (SOC dynamics remains uncertain in this area. In this study, we measured in situ soil respiration and SOC storage over a two-year period (Jan. 2007-Dec. 2008 from five characteristic vegetation types in a forest-steppe ecotone of temperate China, including grassland (GR, shrubland (SH, as well as in evergreen coniferous (EC, deciduous coniferous (DC and deciduous broadleaved forest (DB, to evaluate the changes of soil respiration and SOC storage with grassland conversions to diverse types of woodlands. Annual soil respiration increased by 3%, 6%, 14%, and 22% after the conversion from GR to EC, SH, DC, and DB, respectively. The variation in soil respiration among different vegetation types could be well explained by SOC and soil total nitrogen content. Despite higher soil respiration in woodlands, SOC storage and residence time increased in the upper 20 cm of soil. Our results suggest that the differences in soil environmental conditions, especially soil substrate availability, influenced the level of annual soil respiration produced by different vegetation types. Moreover, shifts from grassland to woody plant dominance resulted in increased SOC storage. Given the widespread increase in woody plant abundance caused by climate change and large-scale afforestation programs, the soils are expected to accumulate and store increased amounts of organic carbon in temperate areas of China.

  8. The role of p38 in mitochondrial respiration in male and female mice.

    Ju, Xiaohua; Wen, Yi; Metzger, Daniel; Jung, Marianna

    2013-06-07

    p38 is a mitogen-activated protein kinase and mediates cell growth, cell differentiation, and synaptic plasticity. The aim of this study is to determine the extent to which p38 plays a role in maintaining mitochondrial respiration in male and female mice under a normal condition. To achieve this aim, we have generated transgenic mice that lack p38 in cerebellar Purkinje neurons by crossing Pcp2 (Purkinje cell protein 2)-Cre mice with p38(loxP/loxP) mice. Mitochondria from cerebellum were then isolated from the transgenic and wild-type mice to measure mitochondrial respiration using XF24 respirometer. The mRNA and protein expression of cytochrome c oxidase (COX) in cerebellum were also measured using RT-PCR and immunoblot methods. Separately, HT22 cells were used to determine the involvement of 17β-estradiol (E2) and COX in mitochondrial respiration. The genetic knockout of p38 in Purkinje neurons suppressed the mitochondrial respiration only in male mice and increased COX expression only in female mice. The inhibition of COX by sodium azide (SA) sharply suppressed mitochondrial respiration of HT22 cells in a manner that was protected by E2. These data suggest that p38 is required for the mitochondrial respiration of male mice. When p38 is below a normal level, females may maintain mitochondrial respiration through COX up-regulation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Measurement and Modeling of Respiration Rate of Tomato (Cultivar Roma) for Modified Atmosphere Storage.

    Kandasamy, Palani; Moitra, Ranabir; Mukherjee, Souti

    2015-01-01

    Experiments were conducted to determine the respiration rate of tomato at 10, 20 and 30 °C using closed respiration system. Oxygen depletion and carbon dioxide accumulation in the system containing tomato was monitored. Respiration rate was found to decrease with increasing CO2 and decreasing O2 concentration. Michaelis-Menten type model based on enzyme kinetics was evaluated using experimental data generated for predicting the respiration rate. The model parameters that obtained from the respiration rate at different O2 and CO2 concentration levels were used to fit the model against the storage temperatures. The fitting was fair (R2 = 0.923 to 0.970) when the respiration rate was expressed as O2 concentation. Since inhibition constant for CO2 concentration tended towards negetive, the model was modified as a function of O2 concentration only. The modified model was fitted to the experimental data and showed good agreement (R2 = 0.998) with experimentally estimated respiration rate.

  10. Performance comparison of various time variant filters

    Kuwata, M [JEOL Engineering Co. Ltd., Akishima, Tokyo (Japan); Husimi, K

    1996-07-01

    This paper describes the advantage of the trapezoidal filter used in semiconductor detector system comparing with the other time variant filters. The trapezoidal filter is the compose of a rectangular pre-filter and a gated integrator. We indicate that the best performance is obtained by the differential-integral summing type rectangular pre-filter. This filter is not only superior in performance, but also has the useful feature that the rising edge of the output waveform is linear. We introduce an example of this feature used in a high-energy experiment. (author)

  11. Workplace performance of a loose-fitting powered air purifying respirator during nanoparticle synthesis

    Koivisto, Antti J.; Aromaa, Mikko; Koponen, Ismo K.; Fransman, Wouter; Jensen, Keld A.; Mäkelä, Jyrki M.; Hämeri, Kaarle J.

    2015-01-01

    Nanoparticle (particles with diameter ≤100 nm) exposure is recognized as a potentially harmful size fraction for pulmonary particle exposure. During nanoparticle synthesis, the number concentrations in the process room may exceed 10 × 10 6 cm −3 . During such conditions, it is essential that the occupants in the room wear highly reliable high-performance respirators to prevent inhalation exposure. Here we have studied the in-use program protection factor (PPF) of loose-fitting powered air purifying respirators, while workers were coating components with TiO 2 or Cu x O y nanoparticles under a hood using a liquid flame spray process. The PPF was measured using condensation particle counters, an electrical low pressure impactor, and diffusion chargers. The room particle concentrations varied from 4 × 10 6 to 40 × 10 6 cm −3 , and the count median aerodynamic diameter ranged from 32 to 180 nm. Concentrations inside the respirator varied from 0.7 to 7.2 cm −3 . However, on average, tidal breathing was assumed to increase the respirator concentration by 2.3 cm −3 . The derived PPF exceeded 1.1 × 10 6 , which is more than 40 × 10 3 times the respirator assigned protection factor. We were unable to measure clear differences in the PPF of respirators with old and new filters, among two male and one female user, or assess most penetrating particle size. This study shows that the loose-fitting powered air purifying respirator provides very efficient protection against nanoparticle inhalation exposure if used properly

  12. Workplace performance of a loose-fitting powered air purifying respirator during nanoparticle synthesis

    Koivisto, Antti J., E-mail: jok@nrcwe.dk [National Research Centre for the Working Environment (Denmark); Aromaa, Mikko [Tampere University of Technology, Department of Physics (Finland); Koponen, Ismo K. [National Research Centre for the Working Environment (Denmark); Fransman, Wouter [TNO (Netherlands); Jensen, Keld A. [National Research Centre for the Working Environment (Denmark); Mäkelä, Jyrki M. [Tampere University of Technology, Department of Physics (Finland); Hämeri, Kaarle J. [University of Helsinki, Department of Physics (Finland)

    2015-04-15

    Nanoparticle (particles with diameter ≤100 nm) exposure is recognized as a potentially harmful size fraction for pulmonary particle exposure. During nanoparticle synthesis, the number concentrations in the process room may exceed 10 × 10{sup 6} cm{sup −3}. During such conditions, it is essential that the occupants in the room wear highly reliable high-performance respirators to prevent inhalation exposure. Here we have studied the in-use program protection factor (PPF) of loose-fitting powered air purifying respirators, while workers were coating components with TiO{sub 2} or Cu{sub x}O{sub y} nanoparticles under a hood using a liquid flame spray process. The PPF was measured using condensation particle counters, an electrical low pressure impactor, and diffusion chargers. The room particle concentrations varied from 4 × 10{sup 6} to 40 × 10{sup 6} cm{sup −3}, and the count median aerodynamic diameter ranged from 32 to 180 nm. Concentrations inside the respirator varied from 0.7 to 7.2 cm{sup −3}. However, on average, tidal breathing was assumed to increase the respirator concentration by 2.3 cm{sup −3}. The derived PPF exceeded 1.1 × 10{sup 6}, which is more than 40 × 10{sup 3} times the respirator assigned protection factor. We were unable to measure clear differences in the PPF of respirators with old and new filters, among two male and one female user, or assess most penetrating particle size. This study shows that the loose-fitting powered air purifying respirator provides very efficient protection against nanoparticle inhalation exposure if used properly.

  13. Poster — Thur Eve — 37: Respiratory gating with an Elekta flattening filter free photon beam

    Péloquin, S; Furstoss, C; Munger, P; Wierzbicki, W; Carrier, J-F

    2014-01-01

    In cases where surgery is not possible for lung cancer treatment, stereotactic body radiation therapy (SBRT) may be an option. One problem when treating this type of cancer is the motion of the lungs caused by the patient's respiration. It is possible to reduce the impact of this movement with the use of respiratory gating. By combining respiratory gating with a flattening filter free (FFF) photon beam linac, the increased treatment time caused by a reduced beam-on time of respiratory gating methods can be compensated by the inherent increased dose rate of FFF beams. This project's aim is to create hardware and software interfaces allowing free respiration gating on an Elekta Synergy-S linac specially modified to deliver 6 MV FFF photon beams. First, a printed circuit board was created for reading the signal from a Bellows Belt from Philips (a respiration monitor belt) and transmitting an On/Off signal to the accelerator. A software was also developed to visualize patient respiration. Secondly, a FFF model was created with the Pinnacle treatment planning system from Philips. Gamma (Γ) analysis (2%, 2 mm) was used to evaluate model. For fields going from 5.6 × 5.6 to 12 × 12 cm 2 , central axis depth dose model fitting shows an average gamma value of 0.2 and 100% of gamma values remain under the Γ = 1 limit. For smaller fields (0.8 × 0.8 and 1.6 × 1.6 cm 2 ), Pinnacle has more trouble trying to fit the measurements, overestimating dose in penumbra and buildup regions

  14. Electrochemical oxidation of bio-refractory dye in a simulated textile industry effluent using DSA electrodes in a filter-press type FM01-LC reactor.

    Rodríguez, Francisca A; Mateo, María N; Aceves, Juan M; Rivero, Eligio P; González, Ignacio

    2013-01-01

    This work presents a study on degradation of indigo carmine dye in a filter-press type FM01-LC reactor using Sb2O5-doped Ti/IrO2-SnO2 dimensionally stable anode (DSA) electrodes. Micro- and macroelectrolysis studies were carried out using solutions of 0.8 mM indigo carmine in 0.05 M NaCl, which resemble blue denim laundry industrial wastewater. Microelectrolysis results show the behaviour of DSA electrodes in comparison with the behaviour of boron-doped diamond (BDD) electrodes. In general, dye degradation reactions are carried out indirectly through active chlorine generated on DSA, whereas in the case of BDD electrodes more oxidizing species are formed, mainly OH radicals, on the electrode surface. The well-characterized geometry, flow pattern and mass transport of the FM01-LC reactor used in macroelectrolysis experiments allowed the evaluation of the effect of hydrodynamic conditions on the chlorine-mediated degradation rate. Four values of Reynolds number (Re) (93, 371, 464 and 557) at four current densities (50, 100, 150 and 200 A/m2) were tested. The results show that the degradation rate is independent of Re at low current density (50 A/m2) but becomes dependent on the Re at high current density (200 A/m2). This behaviour shows the central role of mass transport and the reactor parameters and design. The low energy consumption (2.02 and 9.04 kWh/m3 for complete discolouration and chemical oxygen demand elimination at 50 A/m2, respectively) and the low cost of DSA electrodes compared to BDD make DSA electrodes promising for practical application in treating industrial textile effluents. In the present study, chlorinated organic compounds were not detected.

  15. The Effect of Restoration on Soil Respiration in an Urban Tidal Wetland in the Meadowlands, New Jersey

    Schafer, K. V.; Kurepa, S.; Duman, T.; Scott, M.; Pechmann, I.; Vanderklein, D. W.

    2017-12-01

    The effect of wetland restoration on soil respiration in tidal brackish marshes has not been comprehensively studied. In New Jersey, common mitigation efforts come in the form of the removal of an invasive haplotype of Phragmites australis and replanting of native species, resulting in significant habitat disturbance. This study investigated the differences in soil respiration within and between areas covered with P. australis, Spartina alterniflora, and Spartina patens. We performed static chamber measurements of soil respiration using an infrared gas analyzer to measure CO2 fluxes in a natural site and a mitigated site in the Meadowlands of New Jersey. Daytime measurements were performed in 10 random locations in areas populated with each of the vegetation types, to represent the spatial heterogeneity of the wetland area, during summer 2017. Due to the nature of the wetland, vegetation had to be removed to uncover the soil. Prior to measuring exposed soil respiration, we therefore measured CO2 flux including the vegetation within the chamber, which allowed us to additionally calculate the respiration including the vegetation. Furthermore, we assessed direct respiration of green leaves with leaf gas exchange measurements. Combining these different methodologies and scales allow us to estimate the function of different components that contribute to total respiration from the wetland, and how they change spatially and temporally. Initial results showed that soil respiration in P. australis patches was much higher than in both Spartina species, however average vegetation respiration per unit mass was similar across all three. Vegetation respiration and soil respiration are of the same order of magnitude in all three species as well. Also, when respiration with and without vegetation was combined, P. australis showed a considerably higher flux.

  16. Soil respiration in northern forests exposed to elevated atmospheric carbon dioxide and ozone.

    Pregitzer, Kurt; Loya, Wendy; Kubiske, Mark; Zak, Donald

    2006-06-01

    The aspen free-air CO2 and O3 enrichment (FACTS II-FACE) study in Rhinelander, Wisconsin, USA, is designed to understand the mechanisms by which young northern deciduous forest ecosystems respond to elevated atmospheric carbon dioxide (CO2) and elevated tropospheric ozone (O3) in a replicated, factorial, field experiment. Soil respiration is the second largest flux of carbon (C) in these ecosystems, and the objective of this study was to understand how soil respiration responded to the experimental treatments as these fast-growing stands of pure aspen and birch + aspen approached maximum leaf area. Rates of soil respiration were typically lowest in the elevated O3 treatment. Elevated CO2 significantly stimulated soil respiration (8-26%) compared to the control treatment in both community types over all three growing seasons. In years 6-7 of the experiment, the greatest rates of soil respiration occurred in the interaction treatment (CO2 + O3), and rates of soil respiration were 15-25% greater in this treatment than in the elevated CO2 treatment, depending on year and community type. Two of the treatments, elevated CO2 and elevated CO2 + O3, were fumigated with 13C-depleted CO2, and in these two treatments we used standard isotope mixing models to understand the proportions of new and old C in soil respiration. During the peak of the growing season, C fixed since the initiation of the experiment in 1998 (new C) accounted for 60-80% of total soil respiration. The isotope measurements independently confirmed that more new C was respired from the interaction treatment compared to the elevated CO2 treatment. A period of low soil moisture late in the 2003 growing season resulted in soil respiration with an isotopic signature 4-6 per thousand enriched in 13C compared to sample dates when the percentage soil moisture was higher. In 2004, an extended period of low soil moisture during August and early September, punctuated by a significant rainfall event, resulted in soil

  17. BOREAS TE-5 Soil Respiration Data

    Hall, Forrest G. (Editor); Curd, Shelaine (Editor); Ehleriinger, Jim; Brooks, J. Renee; Flanagan, Larry

    2000-01-01

    The BOREAS TE-5 team collected measurements in the NSA and SSA on gas exchange, gas composition, and tree growth. Soil respiration data were collected from 26-May-94 to 07-Sep-94 in the BOREAS NSA and SSA to compare the soil respiration rates in different forest sites using a LI-COR 6200 soil respiration chamber (model 6299). The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distrobuted Activity Archive Center (DAAC).

  18. Bag filters

    Yoshida, M; Komeda, I; Takizaki, K

    1982-01-01

    Bag filters are widely used throughout the cement industry for recovering raw materials and products and for improving the environment. Their general mechanism, performance and advantages are shown in a classification table, and there are comparisons and explanations. The outer and inner sectional construction of the Shinto ultra-jet collector for pulverized coal is illustrated and there are detailed descriptions of dust cloud prevention, of measures used against possible sources of ignition, of oxygen supply and of other topics. Finally, explanations are given of matters that require careful and comprehensive study when selecting equipment.

  19. Digital filters

    Hamming, Richard W

    1997-01-01

    Digital signals occur in an increasing number of applications: in telephone communications; in radio, television, and stereo sound systems; and in spacecraft transmissions, to name just a few. This introductory text examines digital filtering, the processes of smoothing, predicting, differentiating, integrating, and separating signals, as well as the removal of noise from a signal. The processes bear particular relevance to computer applications, one of the focuses of this book.Readers will find Hamming's analysis accessible and engaging, in recognition of the fact that many people with the s

  20. Aquatic respiration rate measurements at low oxygen concentrations.

    Moritz Holtappels

    Full Text Available Despite its huge ecological importance, microbial oxygen respiration in pelagic waters is little studied, primarily due to methodological difficulties. Respiration measurements are challenging because of the required high resolution of oxygen concentration measurements. Recent improvements in oxygen sensing techniques bear great potential to overcome these limitations. Here we compare 3 different methods to measure oxygen consumption rates at low oxygen concentrations, utilizing amperometric Clark type sensors (STOX, optical sensors (optodes, and mass spectrometry in combination with (18-18O2 labeling. Oxygen concentrations and consumption rates agreed well between the different methods when applied in the same experimental setting. Oxygen consumption rates between 30 and 400 nmol L(-1 h(-1 were measured with high precision and relative standard errors of less than 3%. Rate detection limits in the range of 1 nmol L(-1 h(-1 were suitable for rate determinations in open ocean water and were lowest at the lowest applied O2 concentration.

  1. Aerosol filtration with metallic fibrous filters

    Klein, M.; Goossens, W.R.A.

    1983-01-01

    The filtration efficiency of stainless steel fibrous filters (BEKIPOR porous mats and sintered webs) is determined using submicronic monodisperse polystyrene aerosols. Lasers spectrometers are used for the aerosol measurements. The parameters varied are the fiber diameter, the number of layers, the aerosol diameter and the superficial velocity. Two selected types of filters are tested with polydisperse methylene blue aerosols to determine the effect of bed loading on the filter performance and to test washing techniques for the regeneration of the filter

  2. In Situ Cleanable Alternative HEPA Filter Media

    Adamson, D. J.; Terry, M. T.

    2002-01-01

    The Westinghouse Savannah River Company, located at the Savannah River Site in Aiken, South Carolina, is currently testing two types of filter media for possible deployment as in situ regenerable/cleanable High Efficiency Particulate Air (HEPA) filters. The filters are being investigated to replace conventional, disposable, glass-fiber, HEPA filters that require frequent removal, replacement, and disposal. This is not only costly and subjects site personnel to radiation exposure, but adds to the ever-growing waste disposal problem. The types of filter media being tested, as part of a National Energy Technology Laboratory procurement, are sintered nickel metal and ceramic monolith membrane. These media were subjected to a hostile environment to simulate conditions that challenge the high-level waste tank ventilation systems. The environment promoted rapid filter plugging to maximize the number of filter loading/cleaning cycles that would occur in a specified period of time. The filters were challenged using nonradioactive simulated high-level waste materials and atmospheric dust; materials that cause filter pluggage in the field. The filters are cleaned in situ using an aqueous solution. The study found that both filter media were insensitive to high humidity or moisture conditions and were easily cleaned in situ. The filters regenerated to approximately clean filter status even after numerous plugging and in situ cleaning cycles. Air Techniques International is conducting particle retention testing on the filter media at the Oak Ridge Filter Test Facility. The filters are challenged using 0.3-mm di-octyl phthalate particles. Both the ceramic and sintered media have a particle retention efficiency > 99.97%. The sintered metal and ceramic filters not only can be cleaned in situ, but also hold great potential as a long life alternative to conventional HEPA filters. The Defense Nuclear Facility Safety Board Technical Report, ''HEPA Filters Used in the Department of

  3. Evaluation of the Survivability of Microorganisms Deposited on Filtering Respiratory Protective Devices under Varying Conditions of Humidity

    Katarzyna Majchrzycka

    2016-01-01

    Full Text Available Bioaerosols are common biological factors in work environments, which require routine use of filtering respiratory protective devices (FRPDs. Currently, no studies link humidity changes in the filter materials of such devices, during use, with microorganism survivability. Our aim was to determine the microclimate inside FRPDs, by simulating breathing, and to evaluate microorganism survivability under varying humidity conditions. Breathing was simulated using commercial filtering facepiece respirators in a model system. Polypropylene melt-blown nonwoven fabrics with moisture contents of 40%, 80%, and 200%, were used for assessment of microorganisms survivability. A modified AATCC 100-2004 method was used to measure the survivability of ATCC and NCAIM microorganisms: Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Candida albicans and Aspergillus niger. During simulation relative humidity under the facepiece increased after 7 min of usage to 84%–92% and temperature increased to 29–30 °C. S. aureus survived the best on filter materials with 40%–200% moisture content. A decrease in survivability was observed for E. coli and C. albicans when mass humidity decreased. We found that B. subtilis and A. niger proliferated for 48–72 h of incubation and then died regardless of the moisture content. In conclusion, our tests showed that the survivability of microorganisms on filter materials depends on the amount of accumulated moisture and microorganism type.

  4. Evaluation of the Survivability of Microorganisms Deposited on Filtering Respiratory Protective Devices under Varying Conditions of Humidity.

    Majchrzycka, Katarzyna; Okrasa, Małgorzata; Skóra, Justyna; Gutarowska, Beata

    2016-01-04

    Bioaerosols are common biological factors in work environments, which require routine use of filtering respiratory protective devices (FRPDs). Currently, no studies link humidity changes in the filter materials of such devices, during use, with microorganism survivability. Our aim was to determine the microclimate inside FRPDs, by simulating breathing, and to evaluate microorganism survivability under varying humidity conditions. Breathing was simulated using commercial filtering facepiece respirators in a model system. Polypropylene melt-blown nonwoven fabrics with moisture contents of 40%, 80%, and 200%, were used for assessment of microorganisms survivability. A modified AATCC 100-2004 method was used to measure the survivability of ATCC and NCAIM microorganisms: Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Candida albicans and Aspergillus niger. During simulation relative humidity under the facepiece increased after 7 min of usage to 84%-92% and temperature increased to 29-30 °C. S. aureus survived the best on filter materials with 40%-200% moisture content. A decrease in survivability was observed for E. coli and C. albicans when mass humidity decreased. We found that B. subtilis and A. niger proliferated for 48-72 h of incubation and then died regardless of the moisture content. In conclusion, our tests showed that the survivability of microorganisms on filter materials depends on the amount of accumulated moisture and microorganism type.

  5. [Characteristics of Soil Respiration along Eroded Sloping Land with Different SOC Background on the Hilly Loess Plateau].

    Chen, Gai; Xu, Ming-xiang; Zhang, Ya-feng; Wang, Chao-hua; Fan, Hui-min; Wang, Shan-shan

    2015-09-01

    This study aimed to characterize soil respiration along eroded sloping land at erosion and deposition area under different soil organic carbon(SOC) levels, and linked the relationship between soil respiration and soil temperature, soil moisture, SOC and slope position. Experiments were carried out in the plots of S type slopes include five different soil organic carbon levels in the Loess Hilly Region. The S type slopes were divided into control area at the top of the slope, erosion area at the middle of the slope and deposition area at the toe of the slope. We found that soil temperature had a greater impact on soil respiration in the deposition area, whereas soil moisture had a greater impact on soil respiration in the erosion area compared among control area, erosion area and deposition area. In addition, SOC was the most important factor affecting soil respiration, which can explain soil respiration variation 54. 72%, followed by soil moisture, slope position and soil temperature, which explain soil respiration variation 18. 86% , 16. 13% and 10. 29%, respectively. Soil respiration response to erosion showed obvious on-site and off-site effects along the eroded sloping land. Soil respiration in the erosion area was reduced by 21. 14% compared with control area, and soil respiration in the deposition area was increased by 21. 93% compared with control area. Erosion effect on source and sink of carbon emission was correlated with SOC content of the eroded sloping land. When SOC content was higher than 6. 82 g.kg-1, the slope. erosion tended to be a carbon sequestration process, and when SOC content was lower than 3.03 g.kg-1, the slope erosion tended to be a process of the carbon emission source. The model could reflect the relationship between soil respiration and independent variables of soil organic carbon content, soil temperature and moisture.

  6. The Evaluation of Basal Respiration for Various Soil Textures in Ecologically Sensitive Area

    Huličová, P.; Kotorová, D.; Fazekašová, D.; Hynšt, J.

    2017-10-01

    The present contribution was focused on monitoring changes in the soil basal respiration in different textures of soil in the dry polder Beša. The research was conducted between 2012 and 2014 on soil type Fluvisol locations on three soil textures: clay - loam soil, clayey soil and clay soil in three soil depths. The basal respiration (BR) has been determine by soil CO2 production measuring from incubated soil samples in serum bottles in laboratory condition. Release Co2 has been analysed by gas chromatography. Content of clay particles were in the range 52.18 % to 81.31%, indicating the high difference between the minimum and maximum content. By using of multiple LSD-test we recorded statistically significant impact of clay on basal respiration. Results confirm the values of basal respiration with the depth of the soil profile decreased.

  7. Experimental warming does not enhance soil respiration in a semiarid temperate forest-steppe ecosystem

    Lellei-Kovacs, E.; Kovacs-Lang, E.; Kalapos, T.

    2008-01-01

    are still limited. Soil respiration rate-measured monthly between April and November from 2003 to 2006-remained very low (0.09 - 1.53 mu mol CO2 m(-2) s(-1))in accordance with the moderate biological activity and low humus content of the nutrient poor, coarse sandy soil. Specific soil respiration rate...... ( calculated for unit soil organic matter content), however, was relatively high (0.36 - 7.92 mu mol CO g(-1) C(org)h(-1)) suggesting substrate limitation for soil biological activity. During the day, soil respiration rate was significantly lower at dawn than at midday, while seasonally clear temperature......The influence of simulated climate change on soil respiration was studied in a field experiment on 4 m x 5 m plots in the semiarid temperate Pannonian sand forest-steppe. This ecosystem type has low productivity and soil organic matter content, and covers large areas, yet data on soil carbon fluxes...

  8. How much work is expended for respiration?

    Johnson, A T

    1993-01-01

    The rate of work expended to move air in the respiratory system has been determined for five different airflow waveshapes, a non-linear respiratory model and five exercise levels. As expected, the rectangular waveshape was the most efficient. Model conditions were then changed one a time: (i) starting lung volume was allowed to vary, (ii) exhalation flow limitation was added, (iii) respiration was considered to be a metabolic burden determining part of the ventilation requirement and (iv) a respirator mask was added. Although there is no direct work advantage to varying initial lung volume, such volume changes appear to be dictated by the asymmetry of lung recoil pressure about the lung relaxation volume; allowing the work of respiration to become a metabolic burden clearly shows why respiratory waveforms change from rest to exercise; and, adding a respirator imposes a severe respiratory burden on the wearer engaging in moderate, heavy and very heavy exercise.

  9. Separating rhizosphere respiration from total soil respiration in two larch plantations in northeastern China.

    Jiang, Lifen; Shi, Fuchen; Li, Bo; Luo, Yiqi; Chen, Jiquan; Chen, Jiakuan

    2005-09-01

    The potential capacity of soil to sequester carbon in response to global warming is strongly regulated by the ratio of rhizosphere respiration to respiration by soil microbial decomposers, because of their different temperature sensitivities. To quantify relative contributions of rhizosphere respiration to total soil respiration as influenced by forest stand development, we conducted a trenching study in two larch (Larix gmelini (Rupr.) Rupr.) plantations, aged 17 and 31 years, in northeastern China. Four plots in each plantation were randomly selected and trenched in early May 2001. Soil surface CO2 effluxes both inside and outside the plots were measured from May 2001 to August 2002. Soil respiration (i.e., the CO2 effluxes outside the trenched plots) varied similarly in the two plantations from 0.8 micromol m(-2) s(-1) in winter to 6.0 micromol m(-2) s(-1) in summer. Rhizosphere respiration (i.e., CO2 efflux outside the trenched plots minus that inside the plots) varied from 0.2 to 2.0 micromol m(-2) s(-1) in the old forest and from 0.3 to 4.0 micromol m(-2) s(-1) in the young forest over the seasons. Rhizosphere respiration, on average, accounted for 25% of soil respiration in the old forest and 65% in the young forest. Rhizosphere and soil respiration were significantly correlated with soil temperature but not with soil water content. We conclude that the role forests play in regulating climate change may depend on their age.

  10. Soil respiration in typical plant communities in the wetland surrounding the high-salinity Ebinur Lake

    Li, Yanhong; Zhao, Mingliang; Li, Fadong

    2018-03-01

    Soil respiration in wetlands surrounding lakes is a vital component of the soil carbon cycle in arid regions. However, information remains limited on the soil respiration around highly saline lakes during the plant growing season. Here, we aimed to evaluate diurnal and seasonal variation in soil respiration to elucidate the controlling factors in the wetland of Ebinur Lake, Xinjiang Uygur Autonomous Region, western China. We used a soil carbon flux automatic analyzer (LI-840A) to measure soil respiration rates during the growing season (April to November) in two fields covered by reeds and tamarisk and one field with no vegetation (bare soil) from 2015 to 2016. The results showed a single peak in the diurnal pattern of soil respiration from 11:00 to 17:00 for plots covered in reeds, tamarisk, and bare soil, with minimum values being detected from 03:00 to 07:00. During the growing season, the soil respiration of reeds and tamarisk peaked during the thriving period (4.16 and 3.75 mmol•m-2•s-1, respectively), while that of bare soil peaked during the intermediate growth period (0.74 mmol•m-2•s-1). The soil respiration in all three plots was lowest during the wintering period (0.08, 0.09, and-0.87 mmol•m-2•s-1, respectively). Air temperature and relative humidity significantly influenced soil respiration. A significant linear relationship was detected between soil respiration and soil temperature for reeds, tamarisk, and bare soil. The average Q10 of reeds and tamarisk were larger than that of bare soil. However, soil moisture content was not the main factor controlling soil respiration. Soil respiration was negatively correlated with soil pH and soil salinity in all three plot types. In contrast, soil respiration was positively correlated with organic carbon. Overall, CO2 emissions and greenhouse gases had a relatively weak effect on the wetlands surrounding the highly saline Ebinur Lake.

  11. Molecular Characterization of Bacterial Respiration on Minerals

    Blake, Robert C.

    2013-04-26

    The overall aim of this project was to contribute to our fundamental understanding of proteins and biological processes under extreme environmental conditions. We sought to define the biochemical and physiological mechanisms that underlie biodegradative and other cellular processes in normal, extreme, and engineered environments. Toward that end, we sought to understand the substrate oxidation pathways, the electron transport mechanisms, and the modes of energy conservation employed during respiration by bacteria on soluble iron and insoluble sulfide minerals. In accordance with these general aims, the specific aims were two-fold: To identify, separate, and characterize the extracellular biomolecules necessary for aerobic respiration on iron under strongly acidic conditions; and to elucidate the molecular principles whereby these bacteria recognize and adhere to their insoluble mineral substrates under harsh environmental conditions. The results of these studies were described in a total of nineteen manuscripts. Highlights include the following: 1. The complete genome of Acidithiobacillus ferrooxidans ATCC 23270 (type strain) was sequenced in collaboration with the DOE Joint Genome Institute; 2. Genomic and mass spectrometry-based proteomic methods were used to evaluate gene expression and in situ microbial activity in a low-complexity natural acid mine drainage microbial biofilm community. This was the first effort to successfully analyze a natural community using these techniques; 3. Detailed functional and structural studies were conducted on rusticyanin, an acid-stable electron transfer protein purified from cell-free extracts of At. ferrooxidans. The three-dimensional structure of reduced rusticyanin was determined from a combination of homonuclear proton and heteronuclear 15N- and 13C-edited NMR spectra. Concomitantly, the three-dimensional structure of oxidized rusticyanin was determined by X-ray crystallography to a resolution of 1.9 A by multiwavelength

  12. Respiration of Nitrate and Nitrite.

    Cole, Jeffrey A; Richardson, David J

    2008-09-01

    Nitrate reduction to ammonia via nitrite occurs widely as an anabolic process through which bacteria, archaea, and plants can assimilate nitrate into cellular biomass. Escherichia coli and related enteric bacteria can couple the eight-electron reduction of nitrate to ammonium to growth by coupling the nitrate and nitrite reductases involved to energy-conserving respiratory electron transport systems. In global terms, the respiratory reduction of nitrate to ammonium dominates nitrate and nitrite reduction in many electron-rich environments such as anoxic marine sediments and sulfide-rich thermal vents, the human gastrointestinal tract, and the bodies of warm-blooded animals. This review reviews the regulation and enzymology of this process in E. coli and, where relevant detail is available, also in Salmonella and draws comparisons with and implications for the process in other bacteria where it is pertinent to do so. Fatty acids may be present in high levels in many of the natural environments of E. coli and Salmonella in which oxygen is limited but nitrate is available to support respiration. In E. coli, nitrate reduction in the periplasm involves the products of two seven-gene operons, napFDAGHBC, encoding the periplasmic nitrate reductase, and nrfABCDEFG, encoding the periplasmic nitrite reductase. No bacterium has yet been shown to couple a periplasmic nitrate reductase solely to the cytoplasmic nitrite reductase NirB. The cytoplasmic pathway for nitrate reduction to ammonia is restricted almost exclusively to a few groups of facultative anaerobic bacteria that encounter high concentrations of environmental nitrate.

  13. Low-Pass Filtering Approach via Empirical Mode Decomposition Improves Short-Scale Entropy-Based Complexity Estimation of QT Interval Variability in Long QT Syndrome Type 1 Patients

    Vlasta Bari

    2014-09-01

    Full Text Available Entropy-based complexity of cardiovascular variability at short time scales is largely dependent on the noise and/or action of neural circuits operating at high frequencies. This study proposes a technique for canceling fast variations from cardiovascular variability, thus limiting the effect of these overwhelming influences on entropy-based complexity. The low-pass filtering approach is based on the computation of the fastest intrinsic mode function via empirical mode decomposition (EMD and its subtraction from the original variability. Sample entropy was exploited to estimate complexity. The procedure was applied to heart period (HP and QT (interval from Q-wave onset to T-wave end variability derived from 24-hour Holter recordings in 14 non-mutation carriers (NMCs and 34 mutation carriers (MCs subdivided into 11 asymptomatic MCs (AMCs and 23 symptomatic MCs (SMCs. All individuals belonged to the same family developing long QT syndrome type 1 (LQT1 via KCNQ1-A341V mutation. We found that complexity indexes computed over EMD-filtered QT variability differentiated AMCs from NMCs and detected the effect of beta-blocker therapy, while complexity indexes calculated over EMD-filtered HP variability separated AMCs from SMCs. The EMD-based filtering method enhanced features of the cardiovascular control that otherwise would have remained hidden by the dominant presence of noise and/or fast physiological variations, thus improving classification in LQT1.

  14. Linear programming model can explain respiration of fermentation products

    Möller, Philip; Liu, Xiaochen; Schuster, Stefan

    2018-01-01

    Many differentiated cells rely primarily on mitochondrial oxidative phosphorylation for generating energy in the form of ATP needed for cellular metabolism. In contrast most tumor cells instead rely on aerobic glycolysis leading to lactate to about the same extent as on respiration. Warburg found that cancer cells to support oxidative phosphorylation, tend to ferment glucose or other energy source into lactate even in the presence of sufficient oxygen, which is an inefficient way to generate ATP. This effect also occurs in striated muscle cells, activated lymphocytes and microglia, endothelial cells and several mammalian cell types, a phenomenon termed the “Warburg effect”. The effect is paradoxical at first glance because the ATP production rate of aerobic glycolysis is much slower than that of respiration and the energy demands are better to be met by pure oxidative phosphorylation. We tackle this question by building a minimal model including three combined reactions. The new aspect in extension to earlier models is that we take into account the possible uptake and oxidation of the fermentation products. We examine the case where the cell can allocate protein on several enzymes in a varying distribution and model this by a linear programming problem in which the objective is to maximize the ATP production rate under different combinations of constraints on enzymes. Depending on the cost of reactions and limitation of the substrates, this leads to pure respiration, pure fermentation, and a mixture of respiration and fermentation. The model predicts that fermentation products are only oxidized when glucose is scarce or its uptake is severely limited. PMID:29415045

  15. Linear programming model can explain respiration of fermentation products.

    Möller, Philip; Liu, Xiaochen; Schuster, Stefan; Boley, Daniel

    2018-01-01

    Many differentiated cells rely primarily on mitochondrial oxidative phosphorylation for generating energy in the form of ATP needed for cellular metabolism. In contrast most tumor cells instead rely on aerobic glycolysis leading to lactate to about the same extent as on respiration. Warburg found that cancer cells to support oxidative phosphorylation, tend to ferment glucose or other energy source into lactate even in the presence of sufficient oxygen, which is an inefficient way to generate ATP. This effect also occurs in striated muscle cells, activated lymphocytes and microglia, endothelial cells and several mammalian cell types, a phenomenon termed the "Warburg effect". The effect is paradoxical at first glance because the ATP production rate of aerobic glycolysis is much slower than that of respiration and the energy demands are better to be met by pure oxidative phosphorylation. We tackle this question by building a minimal model including three combined reactions. The new aspect in extension to earlier models is that we take into account the possible uptake and oxidation of the fermentation products. We examine the case where the cell can allocate protein on several enzymes in a varying distribution and model this by a linear programming problem in which the objective is to maximize the ATP production rate under different combinations of constraints on enzymes. Depending on the cost of reactions and limitation of the substrates, this leads to pure respiration, pure fermentation, and a mixture of respiration and fermentation. The model predicts that fermentation products are only oxidized when glucose is scarce or its uptake is severely limited.

  16. Measurement of the oxidative potential of PM2.5 and its constituents : The effect of extraction solvent and filter type

    Yang, Aileen; Jedynska, Aleksandra; Hellack, Bryan; Rooter, Ingeborg; Hoek, Gerard; Brunekreef, Bert; Kuhlbusch, Thomas A. J.; Cassee, Flemming R.; Janssen, Nicole A. H.

    The capacity of Particulate Matter (PM) to oxidise target molecules, defined as its oxidative potential (OP), has been proposed as a biologically more relevant metric than PM mass. Different assays exist for measuring OP and their methodologies vary in the choice of extraction solvent and filter

  17. [Research progress on photosynthesis regulating and controlling soil respiration].

    Jing, Yan-Li; Guan, De-Xin; Wu, Jia-Bing; Wang, An-Zhi; Yuan, Feng-Hui

    2013-01-01

    To understand the mechanisms of soil respiration and accurately estimate its magnitude are the crucial basis of evaluating global carbon balance. However, the previously built soil respiration forecast models usually neglect the physiological processes that photosynthesis supplies substrates for rhizospheric respiration, leading to the defect in evaluating the mechanisms of soil respiration. This paper summarized the research progress on the mechanisms of photosynthetic regulation and control of soil respiration, introduced the related main research methods, and discussed the existing problems and research hotspots.

  18. New iodine filter pack design

    Blackbee, B.A.

    1977-10-01

    To enable Naval Emergency Monitoring Teams to fulfil their role in the field it was necessary to locate or design a replacement filter pack for the collection of radioactive iodine air samples. Collaboration with the Berkeley Laboratories of the Central Electricity Generating Board provided the necessary starting point for a suitable type of package. Further development by NGTE (West Drayton) yielded the improved filter pack which is the subject of this memorandum. (author)

  19. Heterogeneous counting on filter support media

    Long, E.; Kohler, V.; Kelly, M.J.

    1976-01-01

    Many investigators in the biomedical research area have used filter paper as the support for radioactive samples. This means that a heterogeneous counting of sample sometimes results. The count rate of a sample on a filter will be affected by positioning, degree of dryness, sample application procedure, the type of filter, and the type of cocktail used. Positioning of the filter (up or down) in the counting vial can cause a variation of 35% or more when counting tritiated samples on filter paper. Samples of varying degrees of dryness when added to the counting cocktail can cause nonreproducible counts if handled improperly. Count rates starting at 2400 CPM initially can become 10,000 CPM in 24 hours for 3 H-DNA (deoxyribonucleic acid) samples dried on standard cellulose acetate membrane filters. Data on cellulose nitrate filters show a similar trend. Sample application procedures in which the sample is applied to the filter in a small spot or on a large amount of the surface area can cause nonreproducible or very low counting rates. A tritiated DNA sample, when applied topically, gives a count rate of 4,000 CPM. When the sample is spread over the whole filter, 13,400 CPM are obtained with a much better coefficient of variation (5% versus 20%). Adding protein carrier (bovine serum albumin-BSA) to the sample to trap more of the tritiated DNA on the filter during the filtration process causes a serious beta absorption problem. Count rates which are one-fourth the count rate applied to the filter are obtained on calibrated runs. Many of the problems encountered can be alleviated by a proper choice of filter and the use of a liquid scintillation cocktail which dissolves the filter. Filter-Solv has been used to dissolve cellulose nitrate filters and filters which are a combination of cellulose nitrate and cellulose acetate. Count rates obtained for these dissolved samples are very reproducible and highly efficient

  20. Particle Kalman Filtering: A Nonlinear Bayesian Framework for Ensemble Kalman Filters*

    Hoteit, Ibrahim

    2012-02-01

    This paper investigates an approximation scheme of the optimal nonlinear Bayesian filter based on the Gaussian mixture representation of the state probability distribution function. The resulting filter is similar to the particle filter, but is different from it in that the standard weight-type correction in the particle filter is complemented by the Kalman-type correction with the associated covariance matrices in the Gaussian mixture. The authors show that this filter is an algorithm in between the Kalman filter and the particle filter, and therefore is referred to as the particle Kalman filter (PKF). In the PKF, the solution of a nonlinear filtering problem is expressed as the weighted average of an “ensemble of Kalman filters” operating in parallel. Running an ensemble of Kalman filters is, however, computationally prohibitive for realistic atmospheric and oceanic data assimilation problems. For this reason, the authors consider the construction of the PKF through an “ensemble” of ensemble Kalman filters (EnKFs) instead, and call the implementation the particle EnKF (PEnKF). It is shown that different types of the EnKFs can be considered as special cases of the PEnKF. Similar to the situation in the particle filter, the authors also introduce a resampling step to the PEnKF in order to reduce the risk of weights collapse and improve the performance of the filter. Numerical experiments with the strongly nonlinear Lorenz-96 model are presented and discussed.

  1. Convergent Filter Bases

    Coghetto Roland

    2015-09-01

    Full Text Available We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections.

  2. Extension of the maintenance cycle of HEPA filters by optimization of the technical characteristics of filters and their construction

    Bella, H.; Stiehl, H.H.; Sinhuber, D.

    1977-01-01

    The knowledge of the parameters of HEPA filters used at present in nuclear plants allows optimization of such filters with respect to flow rate, pressure drop and service life. The application of optimizing new types of HEPA filters of improved performance is reported. The calculated results were checked experimentally. The use of HEPA filters optimized with respect to dust capacity and service life, and the effects of this new type of filter on the reduction of operating and maintenance costs are discussed

  3. Forest harvesting effects on soil temperature, moisture, and respiration in a bottomland hardwood forest

    Londo, A.J.; Messina, M.G.; Schoenholtz, S.H.

    1999-01-01

    The effect of forest disturbance on C cycling has become an issue, given concerns about escalating atmospheric C content. The authors examined the effects of harvest intensity on in situ and laboratory mineral soil respiration in an East Texas bottomland hardwood forest between 6 and 22 mo after harvesting. Treatments included a clearcut, a partial cut wherein approximately 58% of the basal area was removed, and an unharvested control. The soda-lime absorption technique was used for in situ respiration (CO 2 efflux) and the wet alkali method (NaOH) was used for laboratory mineral soil respiration. Soil temperature and moisture content were also measured. Harvesting significantly increased in situ respiration during most sampling periods. This effect was attributed to an increase in live root and microflora activity associated with postharvesting revegetation. In situ respiration increased exponentially (Q 10 relationship) as treatment soil temperatures increased, but followed a parabolic-type pattern through the range of soil moisture measured (mean range 10.4--31.5%). Mean rates of laboratory mineral soil respiration measured during the study were unaffected by cutting treatment for most sampling sessions. Overall, the mean rate of CO 2 efflux in the clearcuts was significantly higher than that in the partial cuts, which in turn was significantly higher than that in the controls. Mass balance estimates indicate that these treatment differences will have little or no long-term effect on C sequestration of these managed forests

  4. Roots affect the response of heterotrophic soil respiration to temperature in tussock grass microcosms.

    Graham, Scott L; Millard, Peter; Hunt, John E; Rogers, Graeme N D; Whitehead, David

    2012-07-01

    While the temperature response of soil respiration (R(S)) has been well studied, the partitioning of heterotrophic respiration (R(H)) by soil microbes from autotrophic respiration (R(A)) by roots, known to have distinct temperature sensitivities, has been problematic. Further complexity stems from the presence of roots affecting R(H), the rhizosphere priming effect. In this study the short-term temperature responses of R(A) and R(H) in relation to rhizosphere priming are investigated. Temperature responses of R(A), R(H) and rhizosphere priming were assessed in microcosms of Poa cita using a natural abundance δ(13)C discrimination approach. The temperature response of R(S) was found to be regulated primarily by R(A), which accounted for 70 % of total soil respiration. Heterotrophic respiration was less sensitive to temperature in the presence of plant roots, resulting in negative priming effects with increasing temperature. The results emphasize the importance of roots in regulating the temperature response of R(S), and a framework is presented for further investigation into temperature effects on heterotrophic respiration and rhizosphere priming, which could be applied to other soil and vegetation types to improve models of soil carbon turnover.

  5. Seasonal and episodic moisture controls on plant and microbial contributions to soil respiration.

    Carbone, Mariah S; Still, Christopher J; Ambrose, Anthony R; Dawson, Todd E; Williams, A Park; Boot, Claudia M; Schaeffer, Sean M; Schimel, Joshua P

    2011-09-01

    Moisture inputs drive soil respiration (SR) dynamics in semi-arid and arid ecosystems. However, determining the contributions of root and microbial respiration to SR, and their separate temporal responses to periodic drought and water pulses, remains poorly understood. This study was conducted in a pine forest ecosystem with a Mediterranean-type climate that receives seasonally varying precipitation inputs from both rainfall (in the winter) and fog-drip (primarily in the summer). We used automated SR measurements, radiocarbon SR source partitioning, and a water addition experiment to understand how SR, and its separate root and microbial sources, respond to seasonal and episodic changes in moisture. Seasonal changes in SR were driven by surface soil water content and large changes in root respiration contributions. Superimposed on these seasonal patterns were episodic pulses of precipitation that determined the short-term SR patterns. Warm season precipitation pulses derived from fog-drip, and rainfall following extended dry periods, stimulated the largest SR responses. Microbial respiration dominated these SR responses, increasing within hours, whereas root respiration responded more slowly over days. We conclude that root and microbial respiration sources respond differently in timing and magnitude to both seasonal and episodic moisture inputs. These findings have important implications for the mechanistic representation of SR in models and the response of dry ecosystems to changes in precipitation patterns.

  6. [Soil respiration dynamics and its controlling factors of typical vegetation communities on meadow steppes in the western Songnen Plain].

    Wang, Ming; Liu, Xing-Tu; Li, Xiu-Jun; Zhang, Ji-Tao; Wang, Guo-Dong; Lu, Xin-Rui; Li, Xiao-Yu

    2014-01-01

    In order to accurately explore the soil respiration dynamics and its controlling factors of typical vegetation types in the western Songnen Plain, soil respiration rates of Chloris virgata, Puccinellia distans, Phragmites australis and Leymus chinensis communities were measured. The results showed that the diurnal curves of soil respiration rates of the four vegetation communities had simple peak values, which appeared at 11:00-15:00, and the valley values occurred at 21:00-1:00 or 3:00-5:00. The seasonal dynamic patterns of their soil respiration rates were similar, with the maximum (3.21-4.84 micromol CO2 x m(-2) x s(-1)) occurring in July and August and the minimum (0.46-1.51 micromol CO2 x m(-2) x s(-1)) in October. The soil respiration rates of the four vegetation communities had significant exponential correlations with ambient air temperature and soil temperature. Soil moisture, however, only played an important role in affecting the soil respiration rate of C. virgata community while air humidity near the soil surface was significantly correlated with the soil respiration rates of P. australis and L. chinensis communities. The soil salt contents seriously constrained the CO2 dioxide emission, and the soil pH, electrical conductivity (EC), exchangeable sodium percentage (ESP) could explain 87%-91% spatial variations of the soil respiration rate.

  7. Filtering in the time and frequency domains

    Blinchikoff, Herman

    2001-01-01

    Long regarded as a classic of filter theory and design, this book stands as the most comprehensive treatment of filtering techniques, devices and concepts as well as pertinent mathematical relationships. Analysis and theory are supplemented by detailed design curves, fully explained examples and problem and answer sections. Discussed are the derivation of filtering functions, Fourier, Laplace, Hilbert and z transforms, lowpass responses, the transformation of lowpass into other filter types, the all-pass function, the effect of losses on theoretical responses, matched filtering, methods of tim

  8. Visual colorimetry for trace antimony(V) by ion-pair solid-phase extraction with bis[2-(5-chloro-2-pyridylazo)-5-diethylaminophenolato]cobalt(III) on a PTFE type membrane filter.

    Mizuguchi, Hitoshi; Matsuda, Yuki; Mori, Takehito; Uehara, Atsushi; Ishikawa, Yuta; Endo, Masatoshi; Shida, Junichi

    2008-02-01

    A new visual colorimetry for trace antimony(V) based on ion-pair solid-phase extraction to a PTFE-type membrane filter with bis[2-(5-chloro-2-pyridylazo)-5-diethylaminophenolato]cobalt(III) ion ([Co(5-Cl-PADAP)(2)](+)) has been developed. Experiments showed that hexachloroantimonate(V) ion (SbCl(6)(-)) was adsorbed with [Co(5-Cl-PADAP)(2)](+) to the front surface of the PTFE filter. The adsorption of antimony(V) ion was promoted by the addition of lithium chloride as a source of chloride ion. The excess reagent of [Co(5-Cl-PADAP)(2)](+) was eluted by rinsing with a 10 wt% methanol aqueous solution. In this case, the slow rate of the hydrolysis reaction of SbCl(6)(-) and the difference of the hydrophobicity of the ion pairs were important for adsorption and separation with a PTFE-type membrane filter. The antimony(V) concentration was determined through a visual comparison with a standard series. The visual detection limit was 0.10 microg. The calibration curve assessed with the reflection spectrometric responses at 580 nm was linear in the concentration range of 0.10 - 1.2 microg (r = 0.996). The proposed method has been applied to the determination of sub-microgram levels of antimony(V) ion in water samples.

  9. Improving respiration measurements with gas exchange analyzers.

    Montero, R; Ribas-Carbó, M; Del Saz, N F; El Aou-Ouad, H; Berry, J A; Flexas, J; Bota, J

    2016-12-01

    Dark respiration measurements with open-flow gas exchange analyzers are often questioned for their low accuracy as their low values often reach the precision limit of the instrument. Respiration was measured in five species, two hypostomatous (Vitis Vinifera L. and Acanthus mollis) and three amphistomatous, one with similar amount of stomata in both sides (Eucalyptus citriodora) and two with different stomata density (Brassica oleracea and Vicia faba). CO 2 differential (ΔCO 2 ) increased two-fold with no change in apparent R d , when the two leaves with higher stomatal density faced outside. These results showed a clear effect of the position of stomata on ΔCO 2 . Therefore, it can be concluded that leaf position is important to guarantee the improvement of respiration measurements increasing ΔCO 2 without affecting the respiration results by leaf or mass units. This method will help to increase the accuracy of leaf respiration measurements using gas exchange analyzers. Copyright © 2016 Elsevier GmbH. All rights reserved.

  10. Simplified pressure method for respirator fit testing.

    Han, D; Xu, M; Foo, S; Pilacinski, W; Willeke, K

    1991-08-01

    A simplified pressure method has been developed for fit testing air-purifying respirators. In this method, the air-purifying cartridges are replaced by a pressure-sensing attachment and a valve. While wearers hold their breath, a small pump extracts air from the respirator cavity until a steady-state pressure is reached in 1 to 2 sec. The flow rate through the face seal leak is a unique function of this pressure, which is determined once for all respirators, regardless of the respirator's cavity volume or deformation because of pliability. The contaminant concentration inside the respirator depends on the degree of dilution by the flow through the cartridges. The cartridge flow varies among different brands and is measured once for each brand. The ratio of cartridge to leakflow is a measure of fit. This flow ratio has been measured on human subjects and has been compared to fit factors determined on the same subjects by means of photometric and particle count tests. The aerosol tests gave higher values of fit.

  11. Evaluation of film type QX 807 (SO-368, Kodak Ektachrome MS, Estar thin base, with an equivalent Wratten 2A filter overcoat)

    Lockwood, H. E.

    1975-01-01

    A color film with a sensitivity and color balance equal to SO-368, Kodak MS Ektachrome (Estar thin base) was required for use on the Apollo-Soyuz test project (ASTP). A Wratten 2A filter was required for use with the film to reduce short wavelength effects which frequently produce a blue color balance in aerial photographs. The background regarding a special emulsion which was produced with a 2A filter equivalent as an integral part of an SO-368 film manufactured by Eastman Kodak, the cost for production of the special film, and the results of a series of tests made within PTD to certify the film for ASTP use are documented. The tests conducted and documented were physical inspection, process compatibility, effective sensitivity, color balance, cross section analysis, resolution, spectral sensitivity, consistency of results, and picture sample analysis.

  12. Miniaturized dielectric waveguide filters

    Sandhu, MY; Hunter, IC

    2016-01-01

    Design techniques for a new class of integrated monolithic high-permittivity ceramic waveguide filters are presented. These filters enable a size reduction of 50% compared to air-filled transverse electromagnetic filters with the same unloaded Q-factor. Designs for Chebyshev and asymmetric generalised Chebyshev filter and a diplexer are presented with experimental results for an 1800 MHz Chebyshev filter and a 1700 MHz generalised Chebyshev filter showing excellent agreement with theory.

  13. Relationship between oxygen concentration, respiration and filtration rate in blue mussel Mytilus edulis

    Tang, Baojun; Riisgård, Hans Ulrik

    2018-03-01

    The large water-pumping and particle-capturing gills of the filter-feeding blue mussel Mytilus edulis are oversized for respiratory purposes. Consequently, the oxygen uptake rate of the mussel has been suggested to be rather insensitive to decreasing oxygen concentrations in the ambient water, since the diffusion rate of oxygen from water flowing through the mussel determines oxygen uptake. We tested this hypothesis by measuring the oxygen uptake in mussels exposed to various oxygen concentrations. These concentrations were established via N2-bubbling of the water in a respiration chamber with mussels fed algal cells to stimulate fully opening of the valves. It was found that mussels exposed to oxygen concentrations decreasing from 9 to 2 mg O2/L resulted in a slow but significant reduction in the respiration rate, while the filtration rate remained high and constant. Thus, a decrease of oxygen concentration by 78% only resulted in a 25% decrease in respiration rate. However, at oxygen concentrations below 2 mg O2/L M. edulis responded by gradually closing its valves, resulting in a rapid decrease of filtration rate, concurrent with a rapid reduction of respiration rate. These observations indicated that M. edulis is no longer able to maintain its normal aerobic metabolism at oxygen concentration below 2 mg O2/L, and there seems to be an energy-saving mechanism in bivalve molluscs to strongly reduce their activity when exposed to low oxygen conditions.

  14. Negative Regulation of STAT3 Protein-mediated Cellular Respiration by SIRT1 Protein

    Bernier, Michel; Paul, Rajib K; Martin-Montalvo, Alejandro

    2011-01-01

    those of wild-type controls. Comparison of profiles of phospho-antibody array data indicated that the deletion of SirT1 was accompanied by constitutive activation of the pro-inflammatory NF-¿B pathway, which is key for STAT3 induction and increased cellular respiration in Sirt1-KO cells. Thus, SIRT1...... cells exhibited higher mitochondrial respiration as compared with wild-type MEFs. Two independent approaches, including ectopic expression of SIRT1 and siRNA-mediated knockdown of STAT3, led to reduction in intracellular ATP levels and increased lactate production in Sirt1-KO cells that were approaching...

  15. Abnormal mitochondrial respiration in failed human myocardium.

    Sharov, V G; Todor, A V; Silverman, N; Goldstein, S; Sabbah, H N

    2000-12-01

    Chronic heart failure (HF) is associated with morphologic abnormalities of cardiac mitochondria including hyperplasia, reduced organelle size and compromised structural integrity. In this study, we examined whether functional abnormalities of mitochondrial respiration are also present in myocardium of patients with advanced HF. Mitochondrial respiration was examined using a Clark electrode in an oxygraph cell containing saponin-skinned muscle bundles obtained from myocardium of failed explanted human hearts due to ischemic (ICM, n=9) or idiopathic dilated (IDC, n=9) cardiomyopathy. Myocardial specimens from five normal donor hearts served as controls (CON). Basal respiratory rate, respiratory rate after addition of the substrates glutamate and malate (V(SUB)), state 3 respiration (after addition of ADP, V(ADP)) and respiration after the addition of atractyloside (V(AT)) were measured in scar-free muscle bundles obtained from the subendocardial (ENDO) and subepicardial (EPI) thirds of the left ventricular (LV) free wall, interventricular septum and right ventricular (RV) free wall. There were no differences in basal and substrate-supported respiration between CON and HF regardless of etiology. V(ADP)was significantly depressed both in ICM and IDC compared to CON in all the regions studied. The respiratory control ratio, V(ADP)/V(AT), was also significantly decreased in HF compared to CON. In both ICM and IDC, V(ADP)was significantly lower in ENDO compared to EPI. The results indicate that mitochondrial respiration is abnormal in the failing human heart. The findings support the concept of low myocardial energy production in HF via oxidative phosphorylation, an abnormality with a potentially impact on global cardiac performance. Copyright 2000 Academic Press.

  16. Heterotrophic soil respiration in forestry-drained peatlands

    Minkkinen, K.; Shurpali, N. J.; Alm, J.; Penttilae, T.

    2007-01-01

    Heterotrophic soil respiration (CO 2 efflux from the decomposition of peat and root litter) in three forestry-drained peatlands with different site types and with a large climatic gradient from the hemi-boreal (central Estonia) to south (southern Finland) and north boreal (northern Finland) conditions was studied. Instantaneous fluxes varied between 0 and 1.3 g CO 2 -C m -2 h -1 , and annual fluxes between 248 and 515 g CO 2 -C m -2 a -1 . Variation in the annual fluxes among site types was studied only in the south-boreal site where we found a clear increase from nutrient-poor to nutrient-rich site types. More than half of the within-site variation was temporal and explained by soil surface (-5 cm) temperature (T5). The response of soil respiration to T5 varied between the sites; the most northerly site had the highest response to T5 and the most southerly the lowest. This trend further resulted in increased annual fluxes towards north. This unexpected result is hypothesised to be related to differences in site factors like substrate quality, nutrient status and hydrology but also to temperature acclimation, i.e., adaptation of decomposer populations to different climates. (orig.)

  17. Flexible time-varying filter banks

    Tuncer, Temel E.; Nguyen, Truong Q.

    1993-09-01

    Linear phase maximally flat FIR Butterworth filter approximations are discussed and a new filter design method is introduced. This variable cutoff filter design method uses the cosine modulated versions of a prototype filter. The design procedure is simple and different variants of this procedure can be used to obtain close to optimum linear phase filters. Using this method, flexible time-varying filter banks with good reconstruction error are introduced. These types of oversampled filter banks have small magnitude error which can be easily controlled by the appropriate choice of modulation frequency. This error can be further decreased by magnitude equalization without increasing the computational complexity considerably. Two dimensional design examples are also given.

  18. Selection vector filter framework

    Lukac, Rastislav; Plataniotis, Konstantinos N.; Smolka, Bogdan; Venetsanopoulos, Anastasios N.

    2003-10-01

    We provide a unified framework of nonlinear vector techniques outputting the lowest ranked vector. The proposed framework constitutes a generalized filter class for multichannel signal processing. A new class of nonlinear selection filters are based on the robust order-statistic theory and the minimization of the weighted distance function to other input samples. The proposed method can be designed to perform a variety of filtering operations including previously developed filtering techniques such as vector median, basic vector directional filter, directional distance filter, weighted vector median filters and weighted directional filters. A wide range of filtering operations is guaranteed by the filter structure with two independent weight vectors for angular and distance domains of the vector space. In order to adapt the filter parameters to varying signal and noise statistics, we provide also the generalized optimization algorithms taking the advantage of the weighted median filters and the relationship between standard median filter and vector median filter. Thus, we can deal with both statistical and deterministic aspects of the filter design process. It will be shown that the proposed method holds the required properties such as the capability of modelling the underlying system in the application at hand, the robustness with respect to errors in the model of underlying system, the availability of the training procedure and finally, the simplicity of filter representation, analysis, design and implementation. Simulation studies also indicate that the new filters are computationally attractive and have excellent performance in environments corrupted by bit errors and impulsive noise.

  19. A comparison of filters for thoracic diagnosis

    Oestmann, J.W.; Hendrickx, P.; Rieder, P.; Geerlings, H.; Medizinische Hochschule Hannover

    1986-01-01

    The effect of three types of filter on the quality of radiographs of the chest was compared. These filters improve visualization of mediastinal structures without significantly reducing the quality of the pulmonary image. In practice the Du Pont filter proved best; the quality of the central and peripheral portions of the lung image is equal to that of an ordinary radiograph and visualization of the mediastinum is improved. The Agfa-Gevaert filter showed no significant disadvantages compared with the ordinary techniques but the improvement in mediastinal visualization is not that marked. The 3M-filter yields poor images of the central portions of the lung and its type of construction prevents the retrocardiac structures from being pictured as well as with the other filters. (orig.) [de

  20. Recirculating electric air filter

    Bergman, W.

    1985-01-09

    An electric air filter cartridge has a cylindrical inner high voltage electrode, a layer of filter material, and an outer ground electrode formed of a plurality of segments moveably connected together. The outer electrode can be easily opened to remove or insert filter material. Air flows through the two electrodes and the filter material and is exhausted from the center of the inner electrode.

  1. Estimating Canopy Dark Respiration for Crop Models

    Monje Mejia, Oscar Alberto

    2014-01-01

    Crop production is obtained from accurate estimates of daily carbon gain.Canopy gross photosynthesis (Pgross) can be estimated from biochemical models of photosynthesis using sun and shaded leaf portions and the amount of intercepted photosyntheticallyactive radiation (PAR).In turn, canopy daily net carbon gain can be estimated from canopy daily gross photosynthesis when canopy dark respiration (Rd) is known.

  2. LIMITATION OF SOIL RESPIRATION DURING DRY PERIOD

    Pavelka, Marian; Janouš, Dalibor; Acosta, Manuel

    2003-01-01

    Roč. 16, - (2003), s. 47-52. ISBN 80-7157-297-7 R&D Projects: GA MŠk LN00A141; GA AV ČR IBS6087005 Institutional research plan: CEZ:AV0Z6087904 Keywords : moisture * Norway spruce * precipitation * respiration * soil CO2 efflux Subject RIV: EH - Ecology, Behaviour

  3. Internal current generation in respiration chambers

    Saborowski, R.; Buchholz, F.

    1998-06-01

    A technical device generating a constant and directed current within a sealed respiration chamber is described. It does not involve any external pumps or tubing. This system is easy to handle, and improved the maintenance of rheotactic pelagic species like the Northern krill ( Meganyctiphanes norvegica, Crustacea) or small fishes ( Gasterosteus aculeatus) under experimental conditions.

  4. 42 CFR 84.1130 - Respirators; description.

    2010-10-01

    ...; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84...., dust clouds produced in mining, quarrying, and tunneling, and in dusts produced during industrial... respective vapors, or from the chemical reaction between their respective vapors and gases. (3) Air-purifying...

  5. Development of conformal respirator monitoring technology

    Shonka, J.J.; Weismann, J.J.; Logan, R.J.

    1997-04-01

    This report summarizes the results of a Small Business Innovative Research Phase II project to develop a modular, surface conforming respirator monitor to improve upon the manual survey techniques presently used by the nuclear industry. Research was performed with plastic scintillator and gas proportional modules in an effort to find the most conducive geometry for a surface conformal, position sensitive monitor. The respirator monitor prototype developed is a computer controlled, position-sensitive detection system employing 56 modular proportional counters mounted in molds conforming to the inner and outer surfaces of a commonly used respirator (Scott Model 801450-40). The molds are housed in separate enclosures and hinged to create a open-quotes waffle-ironclose quotes effect so that the closed monitor will simultaneously survey both surfaces of the respirator. The proportional counter prototype was also designed to incorporate Shonka Research Associates previously developed charge-division electronics. This research provided valuable experience into pixellated position sensitive detection systems. The technology developed can be adapted to other monitoring applications where there is a need for deployment of many traditional radiation detectors

  6. Passive Power Filters

    Künzi, R.

    2015-06-15

    Power converters require passive low-pass filters which are capable of reducing voltage ripples effectively. In contrast to signal filters, the components of power filters must carry large currents or withstand large voltages, respectively. In this paper, three different suitable filter struc tures for d.c./d.c. power converters with inductive load are introduced. The formulas needed to calculate the filter components are derived step by step and practical examples are given. The behaviour of the three discussed filters is compared by means of the examples. P ractical aspects for the realization of power filters are also discussed.

  7. Projects on filter testing in Sweden

    Normann, B.; Wiktorsson, C.

    1985-01-01

    The Swedish nuclear power program comprises twelve light water reactors. Nine are boiling water reactors of ASEA-ATOM design and three are pressurized water reactors of Westinghouse design. Of these, ten are in operation and two are under construction and planned to go into operation during late 1984 and early 1985, respectively. Frequent tests on the penetration of particles through HEPA filters, regular tests on the adsorption of methyl iodide in the stand-by carbon filter units by laboratory testing are discussed. The proposed new regulations are based on many years of experience of filter system operation and of tests in-situ and in the laboratory. Moisture and water are factors that affect the functioning of filters. In addition, high loading of dust can give rise to increased penetration through HEPA filters, however pinholes could have less influence on the total penetration. Laboratory tests show that DOP particles retain 30-40% in 90 mm carbon filters (8-12 mesh). However no effect on the ability of carbon to adsorb methyl iodide after DOP contamination in combined carbon/HEPA filters has been observed. Leakage from ventilation ducts can cause radioactive contamination problems during filter testing with radioiodine. In-situ testing of control-room filters has been performed using inactive methyl iodide. A type of carbon bed not previously used in Sweden has been introduced. Testing of this filter type is discussed

  8. Filter replacement lifetime prediction

    Hamann, Hendrik F.; Klein, Levente I.; Manzer, Dennis G.; Marianno, Fernando J.

    2017-10-25

    Methods and systems for predicting a filter lifetime include building a filter effectiveness history based on contaminant sensor information associated with a filter; determining a rate of filter consumption with a processor based on the filter effectiveness history; and determining a remaining filter lifetime based on the determined rate of filter consumption. Methods and systems for increasing filter economy include measuring contaminants in an internal and an external environment; determining a cost of a corrosion rate increase if unfiltered external air intake is increased for cooling; determining a cost of increased air pressure to filter external air; and if the cost of filtering external air exceeds the cost of the corrosion rate increase, increasing an intake of unfiltered external air.

  9. A Medical Cloud-Based Platform for Respiration Rate Measurement and Hierarchical Classification of Breath Disorders

    Atena Roshan Fekr

    2014-06-01

    Full Text Available The measurement of human respiratory signals is crucial in cyberbiological systems. A disordered breathing pattern can be the first symptom of different physiological, mechanical, or psychological dysfunctions. Therefore, a real-time monitoring of the respiration patterns, as well as respiration rate is a critical need in medical applications. There are several methods for respiration rate measurement. However, despite their accuracy, these methods are expensive and could not be integrated in a body sensor network. In this work, we present a real-time cloud-based platform for both monitoring the respiration rate and breath pattern classification, remotely. The proposed system is designed particularly for patients with breathing problems (e.g., respiratory complications after surgery or sleep disorders. Our system includes calibrated accelerometer sensor, Bluetooth Low Energy (BLE and cloud-computing model. We also suggest a procedure to improve the accuracy of respiration rate for patients at rest positions. The overall error in the respiration rate calculation is obtained 0.53% considering SPR-BTA spirometer as the reference. Five types of respiration disorders, Bradapnea, Tachypnea, Cheyn-stokes, Kaussmal, and Biot’s breathing are classified based on hierarchical Support Vector Machine (SVM with seven different features. We have evaluated the performance of the proposed classification while it is individualized to every subject (case 1 as well as considering all subjects (case 2. Since the selection of kernel function is a key factor to decide SVM’s performance, in this paper three different kernel functions are evaluated. The experiments are conducted with 11 subjects and the average accuracy of 94.52% for case 1 and the accuracy of 81.29% for case 2 are achieved based on Radial Basis Function (RBF. Finally, a performance evaluation has been done for normal and impaired subjects considering sensitivity, specificity and G-mean parameters

  10. Simulation of the air flows in many industrial pleated filters

    Del Fabbro, L.; Brun, P.; Laborde, J.C.; Lacan, J.; Ricciardi, L.; Renoux, A.

    2000-01-01

    The study presents results concerning the characterization of the charge loss and the air flow in nuclear and automobile type pleated filters. The experimental studies in correlation with the numerical models showed an homogenous distribution of the air flows in a THE nuclear type filter, whereas the distribution is heterogenous in the case of an automobile filter. (A.L.B.)

  11. Geochemical importance of isotopic fractionation during respiration

    Schleser, G.; Foerstel, H.

    1975-01-01

    In 1935 it was found that atmospheric oxygen contained a relatively greater abundance of the 18 O isotope than did the oxygen bound in water (Dole effect). A major contribution to the fractionation of the stable oxygen isotopes should result from the respiration of microorganisms. In this respect our interest centers on the soil because nearly all organic material produced on land is decomposed within the soil. The oceans are less important because the primary productivity on land is twice the value for the oceans. In a first approach we measured the oxygen isotope fractionation during the respiration of E. coli K12 for different respiration rates. These results, accomplished with a chemostat, indicate that the fractionation factor α of the oxygen isotopes increases with the increasing respiratory activity, measured as Q/sub O 2 /. At low dilution rates or growth rates respectively of about 0.05 h -1 , the fractionation factor amounts to 1.006 increasing to 1.017 at dilution rates of about 1.0 h -1 . The results are interpreted as a kinetic mass fractionation due to the slightly different diffusion coefficients of 16 O 2 and 18 O 16 O. The respiration rates in conjunction with the corresponding fractionation data are compared with the respiration rates of typical soil microorganisms such as Azotobacter, in order to deduce fractionation data for these organisms. This is necessary to calculate a mean global fractionation factor. Understanding the Dole effect with these fractionation processes should finally give us the opportunity to calculate gas-exchange rates between the atmosphere and the oceans, on the basis of the behavior of the stable oxygen isotopes

  12. Acceptable respiratory protection program and LASL respirator research

    Skaggs, B.J.

    1979-01-01

    A short history is presented on the LASL Respiratory Protection Training Programs. Then a discussion is given on the major points of an acceptable respiratory protection program utilizing the points required by the Occupational, Safety, and Health Administration (OSHA) Regulation 29 CFR 1910.134. Contributions to respirator research are reviewed. Discussion is presented under the following section headings: program administration; respirator selection; respirator use; fitting and training; respirator maintenance; medical clearance and surveillance; special problems; program evaluation; and documentation

  13. Contribution of root to soil respiration and carbon balance in ...

    Soil respiration varied from 2.5 to 11.9 g CO2 m-2 d-1 and from 1.5 to 9.3 g CO2 m-2 d-1, and the contribution of root respiration to total soil respiration from 38% to 76% and from 25% to 72% in Communities 1 and 2, respectively. During the growing season (May–September), soil respiration, shoot biomass, live root ...

  14. Optimization of filter loading

    Turney, J.H.; Gardiner, D.E.; Sacramento Municipal Utility District, Herald, CA)

    1985-01-01

    The introduction of 10 CFR Part 61 has created potential difficulties in the disposal of spent cartridge filters. When this report was prepared, Rancho Seco had no method of packaging and disposing of class B or C filters. This work examined methods to minimize the total operating cost of cartridge filters while maintaining them below the class A limit. It was found that by encapsulating filters in cement the filter operating costs could be minimized

  15. Characteristic of ambient airborne and respirable particulate around a non formal industrial area

    Muhayatun Santoso; Diah Dwiana Lestiani; Mariana Marselina; Rita Mukhtar

    2016-01-01

    Characterization of airborne particulate matter and respirable particulate in Parung Panjang district especially on surrounding non formal used batteries industrial area has been carried out to follow up the previous results with respect to high concentrations of lead detected in Serpong area. Sampling of airborne particulate matter in Parung Panjang was conducted using Gent stacked filter unit sampler, while the respirable particulate matter samples collected using personal dust sampler in Parung Panjang as a non formal Industrial area and Sukarasa village as a control, during 2011-2012. The concentration of masses were determined gravimetrically, while for elemental concentrations by X-Ray based methods. The average of mass concentration of air ambient PM 2.5 and PM 10 in Parung Panjang were 27.3 ± 13.7 and 77.5 ± 17.1 μg.m -3 , respectively. While the average concentration of respirable particulate in non formal industrial and control areas were 260 ± 233 and 82 ± 38 μg.m -3 , respectively. The percentage of average Pb concentration in PM 2.5 and PM 2.5-10 were contribute up to 45 and 10 % of the mass concentration, respectively. The maximum percentage concentration of Pb in respirable particulate in industrial and control area were 12.11 and 0.27 %, respectively. These results showed that the Pb concentrations in respirable particulate in industrial area were significantly tens times higher than in the control area. The high concentration of Pb in Parung Panjang was the main key element came from the used lead battery industry and one of pollutant source that contributed to the Pb pollution in Serpong area. (author)

  16. Nutrients and temperature additively increase stream microbial respiration

    David W. P. Manning; Amy D. Rosemond; Vladislav Gulis; Jonathan P. Benstead; John S. Kominoski

    2017-01-01

    Rising temperatures and nutrient enrichment are co‐occurring global‐change drivers that stimulate microbial respiration of detrital carbon, but nutrient effects on the temperature dependence of respiration in aquatic ecosystems remain uncertain. We measured respiration rates associated with leaf litter, wood, and fine benthic organic matter (FBOM) across...

  17. Thermal adaptation of heterotrophic soil respiration in laboratory microcosms.

    Mark A. Bradford; Brian W. Watts; Christian A. Davies

    2010-01-01

    Respiration of heterotrophic microorganisms decomposing soil organic carbon releases carbon dioxide from soils to the atmosphere. In the short term, soil microbial respiration is strongly dependent on temperature. In the long term, the response of heterotrophic soil respiration to temperature is uncertain. However, following established evolutionary tradeoffs, mass-...

  18. 42 CFR 84.1134 - Respirator containers; minimum requirements.

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84... Combination Gas Masks § 84.1134 Respirator containers; minimum requirements. (a) Except as provided in paragraph (b) of this section each respirator shall be equipped with a substantial, durable container...

  19. 21 CFR 892.1970 - Radiographic ECG/respirator synchronizer.

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiographic ECG/respirator synchronizer. 892.1970... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1970 Radiographic ECG/respirator synchronizer. (a) Identification. A radiographic ECG/respirator synchronizer is a device intended to be used to...

  20. What controls respiration rate in stored sugarbeet roots

    Although respiration is estimated to be responsible for 60 to 80% of the sucrose lost during storage, the mechanisms by which sugarbeet roots regulate their respiration rate are unknown. In plants, respiration rate is regulated by (1) available respiratory capacity, (2) cellular energy status, (3) ...

  1. Redefinition and global estimation of basal ecosystem respiration rate

    Yuan, Wenping; Luo, Yiqi; Li, Xianglan

    2011-01-01

    Basal ecosystem respiration rate (BR), the ecosystem respiration rate at a given temperature, is a common and important parameter in empirical models for quantifying ecosystem respiration (ER) globally. Numerous studies have indicated that BR varies in space. However, many empirical ER models sti...

  2. Quantifying soil respiration at landscape scales. Chapter 11

    John B. Bradford; Michael G. Ryan

    2008-01-01

    Soil CO2, efflux, or soil respiration, represents a substantial component of carbon cycling in terrestrial ecosystems. Consequently, quantifying soil respiration over large areas and long time periods is an increasingly important goal. However, soil respiration rates vary dramatically in space and time in response to both environmental conditions...

  3. Induction by ethylene of cyanide-resistant respiration

    Solomos, T.; Laties, G.G.

    1976-05-17

    Ethylene and cyanide induce an increase in respiration in a variety of plant tissues, whereas ethylene has no effect on tissues whose respiration is strongly inhibited by cyanide. It is suggested that the existence of a cyanide-insensitive electron transport path is a prerequisite for stimulation of respiration by ethylene.

  4. Flow-thermal analysis of power plant with budget dry pocket filter type TTFP 6/220 in foundry AD Kikinda

    Salemović Duško R.

    2014-01-01

    Full Text Available In this paper, the power budget is given in the application of contemporary and modern methods in the treatment of air from the production facility in which the electric arc furnace. For this calculation, for existing construction and known dimensions dusters calculate flow rates and temperatures at various points of the complete piping systems for waste gases. The analysis contributes maximum energy utilization, significant financial savings and increase in energy and environmental efficiency. Engineering supervision and active computer control of a computer in pieces of PLC are supported. The possible errors are diagnosed and their causes are explained and the procedures to be followed when it comes to them. Also, the paper gives the guidelines for the maintenance and servicing of equipment for proper operation of the filter plant. The tables presented in the plant control activities to be conducted at periodic intervals.

  5. Non-contact acquisition of respiration and heart rates using Doppler radar with time domain peak-detection algorithm.

    Xiaofeng Yang; Guanghao Sun; Ishibashi, Koichiro

    2017-07-01

    The non-contact measurement of the respiration rate (RR) and heart rate (HR) using a Doppler radar has attracted more attention in the field of home healthcare monitoring, due to the extremely low burden on patients, unconsciousness and unconstraint. Most of the previous studies have performed the frequency-domain analysis of radar signals to detect the respiration and heartbeat frequency. However, these procedures required long period time (approximately 30 s) windows to obtain a high-resolution spectrum. In this study, we propose a time-domain peak detection algorithm for the fast acquisition of the RR and HR within a breathing cycle (approximately 5 s), including inhalation and exhalation. Signal pre-processing using an analog band-pass filter (BPF) that extracts respiration and heartbeat signals was performed. Thereafter, the HR and RR were calculated using a peak position detection method, which was carried out via LABVIEW. To evaluate the measurement accuracy, we measured the HR and RR of seven subjects in the laboratory. As a reference of HR and RR, the persons wore contact sensors i.e., an electrocardiograph (ECG) and a respiration band. The time domain peak-detection algorithm, based on the Doppler radar, exhibited a significant correlation coefficient of HR of 0.92 and a correlation coefficient of RR of 0.99, between the ECG and respiration band, respectively.

  6. Draft Genome Sequence of Desulfuromonas acetexigens Strain 2873, a Novel Anode-Respiring Bacterium

    Katuri, Krishna

    2017-03-03

    Here, we report the draft genome sequence of Desulfuromonas acetexigens strain 2873, which was originally isolated from digester sludge from a sewage treatment plant in Germany. This bacterium is capable of anode respiration with high electrochemical activity in microbial electrochemical systems. The draft genome contains 3,376 predicted protein-coding genes and putative multiheme c-type cytochromes.

  7. Draft Genome Sequence of Desulfuromonas acetexigens Strain 2873, a Novel Anode-Respiring Bacterium

    Katuri, Krishna; Albertsen, Mads; Saikaly, Pascal

    2017-01-01

    Here, we report the draft genome sequence of Desulfuromonas acetexigens strain 2873, which was originally isolated from digester sludge from a sewage treatment plant in Germany. This bacterium is capable of anode respiration with high electrochemical activity in microbial electrochemical systems. The draft genome contains 3,376 predicted protein-coding genes and putative multiheme c-type cytochromes.

  8. 77 FR 38323 - Proposed Extension of Existing Information Collection; Respirable Coal Mine Dust Sampling

    2012-06-27

    ... Information Collection; Respirable Coal Mine Dust Sampling AGENCY: Mine Safety and Health Administration... Sampling'' to more accurately reflect the type of information that is collected. Chronic exposure to... dust levels since 1970 and, consequently, the prevalence rate of black lung among coal miners, severe...

  9. Root respiration in North American forests: Effects of nitrogen concentration and temperature across biomes

    A.J. Burton; K.S. Pregitzer; R.W. Ruess; R.L. Hendrick; Mike F. Allen

    2002-01-01

    Root respiration rates have been shown to be correlated with temperature and root N concentration in studies of individual forest types or species, but it is not known how universal these relationships are across forest species adapted to widely different climatic and edaphic conditions. In order to test for broad, cross-species relationships, we measured fine root...

  10. Effects of fire disturbance on soil respiration in the non-growing season in a Larix gmelinii forest in the Daxing'an Mountains, China.

    Tongxin Hu

    Full Text Available In boreal forests, fire is an important part of the ecosystem that greatly influences soil respiration, which in turn affects the carbon balance. Wildfire can have a significant effect on soil respiration and it depends on the fire severity and environmental factors (soil temperature and snow water equivalent after fire disturbance. In this study, we quantified post-fire soil respiration during the non-growing season (from November to April in a Larix gmelinii forest in Daxing'an Mountains of China. Soil respiration was measured in the snow-covered and snow-free conditions with varying degrees of natural burn severity forests. We found that soil respiration decreases as burn severity increases. The estimated annual C efflux also decreased with increased burn severity. Soil respiration during the non-growing season approximately accounted for 4%-5% of the annual C efflux in all site types. Soil temperature (at 5 cm depth was the predominant determinant of non-growing season soil respiration change in this area. Soil temperature and snow water equivalent could explain 73%-79% of the soil respiration variability in winter snow-covering period (November to March. Mean spring freeze-thaw cycle (FTC period (April soil respiration contributed 63% of the non-growing season C efflux. Our finding is key for understanding and predicting the potential change in the response of boreal forest ecosystems to fire disturbance under future climate change.

  11. Effects of fire disturbance on soil respiration in the non-growing season in a Larix gmelinii forest in the Daxing'an Mountains, China.

    Hu, Tongxin; Sun, Long; Hu, Haiqing; Guo, Futao

    2017-01-01

    In boreal forests, fire is an important part of the ecosystem that greatly influences soil respiration, which in turn affects the carbon balance. Wildfire can have a significant effect on soil respiration and it depends on the fire severity and environmental factors (soil temperature and snow water equivalent) after fire disturbance. In this study, we quantified post-fire soil respiration during the non-growing season (from November to April) in a Larix gmelinii forest in Daxing'an Mountains of China. Soil respiration was measured in the snow-covered and snow-free conditions with varying degrees of natural burn severity forests. We found that soil respiration decreases as burn severity increases. The estimated annual C efflux also decreased with increased burn severity. Soil respiration during the non-growing season approximately accounted for 4%-5% of the annual C efflux in all site types. Soil temperature (at 5 cm depth) was the predominant determinant of non-growing season soil respiration change in this area. Soil temperature and snow water equivalent could explain 73%-79% of the soil respiration variability in winter snow-covering period (November to March). Mean spring freeze-thaw cycle (FTC) period (April) soil respiration contributed 63% of the non-growing season C efflux. Our finding is key for understanding and predicting the potential change in the response of boreal forest ecosystems to fire disturbance under future climate change.

  12. A distinct seasonal pattern of the ratio of soil respiration to total ecosystem respiration in a spruce-dominated forest

    E.A. Davidson; A.D. Richardson; K.E. Savage; D.Y. Hollinger

    2006-01-01

    Annual budgets and fitted temperature response curves for soil respiration and ecosystem respiration provide useful information for partitioning annual carbon budgets of ecosystems, but they may not adequately reveal seasonal variation in the ratios of these two fluxes. Soil respiration (Rs) typically contributes 30-80% of...

  13. Soil fauna communities and microbial respiration in high Arctic tundra soils at Zackenberg, Northeast Greenland

    Sørensen, Louise I.; Holmstrup, Martin; Maraldo, Kristine

    2006-01-01

    The soil fauna communities were described for three dominant vegetation types in a high arctic site at Zackenberg, Northeast Greenland. Soil samples were extracted to quantify the densities of mites, collembolans, enchytraeids, diptera larvae, nematodes and protozoa. Rates of microbial respiration...... densities (naked amoeba and heterotrophic flagellates) were equal. Respiration rate of unamended soil was similar in soil from the three plots. However, a higher respiration rate increase in carbon + nutrient amended soil and the higher densities of soil fauna (with the exception of mites and protozoa...... were also assessed. Collembolans were found in highest densities in dry heath soil, about 130,000 individuals m-2, more than twice as high as in mesic heath soils. Enchytraeids, diptera larvae and nematodes were also more abundant in the dry heath soil than in mesic heath soils, whereas protozoan...

  14. Multistage parallel-serial time averaging filters

    Theodosiou, G.E.

    1980-01-01

    Here, a new time averaging circuit design, the 'parallel filter' is presented, which can reduce the time jitter, introduced in time measurements using counters of large dimensions. This parallel filter could be considered as a single stage unit circuit which can be repeated an arbitrary number of times in series, thus providing a parallel-serial filter type as a result. The main advantages of such a filter over a serial one are much less electronic gate jitter and time delay for the same amount of total time uncertainty reduction. (orig.)

  15. z-transform DFT filters and FFT's

    Bruun, G.

    1978-01-01

    The paper shows how discrete Fourier transformation can be implemented as a filter bank in a way which reduces the number of filter coefficients. A particular implementation of such a filter bank is directly related to the normal complex FFT algorithm. The principle developed further leads to types...... of DFT filter banks which utilize a minimum of complex coefficients. These implementations lead to new forms of FFT's, among which is acos/sinFFT for a real signal which only employs real coefficients. The new FFT algorithms use only half as many real multiplications as does the classical FFT....

  16. OPTIMIZATION OF ADVANCED FILTER SYSTEMS; TOPICAL

    R.A. Newby; G.J. Bruck; M.A. Alvin; T.E. Lippert

    1998-01-01

    Reliable, maintainable and cost effective hot gas particulate filter technology is critical to the successful commercialization of advanced, coal-fired power generation technologies, such as IGCC and PFBC. In pilot plant testing, the operating reliability of hot gas particulate filters have been periodically compromised by process issues, such as process upsets and difficult ash cake behavior (ash bridging and sintering), and by design issues, such as cantilevered filter elements damaged by ash bridging, or excessively close packing of filtering surfaces resulting in unacceptable pressure drop or filtering surface plugging. This test experience has focused the issues and has helped to define advanced hot gas filter design concepts that offer higher reliability. Westinghouse has identified two advanced ceramic barrier filter concepts that are configured to minimize the possibility of ash bridge formation and to be robust against ash bridges should they occur. The ''inverted candle filter system'' uses arrays of thin-walled, ceramic candle-type filter elements with inside-surface filtering, and contains the filter elements in metal enclosures for complete separation from ash bridges. The ''sheet filter system'' uses ceramic, flat plate filter elements supported from vertical pipe-header arrays that provide geometry that avoids the buildup of ash bridges and allows free fall of the back-pulse released filter cake. The Optimization of Advanced Filter Systems program is being conducted to evaluate these two advanced designs and to ultimately demonstrate one of the concepts in pilot scale. In the Base Contract program, the subject of this report, Westinghouse has developed conceptual designs of the two advanced ceramic barrier filter systems to assess their performance, availability and cost potential, and to identify technical issues that may hinder the commercialization of the technologies. A plan for the Option I, bench-scale test program has also been developed based

  17. Response of soil respiration to acid rain in forests of different maturity in southern China.

    Guohua Liang

    Full Text Available The response of soil respiration to acid rain in forests, especially in forests of different maturity, is poorly understood in southern China despite the fact that acid rain has become a serious environmental threat in this region in recent years. Here, we investigated this issue in three subtropical forests of different maturity [i.e. a young pine forest (PF, a transitional mixed conifer and broadleaf forest (MF and an old-growth broadleaved forest (BF] in southern China. Soil respiration was measured over two years under four simulated acid rain (SAR treatments (CK, the local lake water, pH 4.5; T1, water pH 4.0; T2, water pH 3.5; and T3, water pH 3.0. Results indicated that SAR did not significantly affect soil respiration in the PF, whereas it significantly reduced soil respiration in the MF and the BF. The depressed effects on both forests occurred mostly in the warm-wet seasons and were correlated with a decrease in soil microbial activity and in fine root biomass caused by soil acidification under SAR. The sensitivity of the response of soil respiration to SAR showed an increasing trend with the progressive maturity of the three forests, which may result from their differences in acid buffering ability in soil and in litter layer. These results indicated that the depressed effect of acid rain on soil respiration in southern China may be more pronounced in the future in light of the projected change in forest maturity. However, due to the nature of this field study with chronosequence design and the related pseudoreplication for forest types, this inference should be read with caution. Further studies are needed to draw rigorous conclusions regarding the response differences among forests of different maturity using replicated forest types.

  18. Response of soil respiration to acid rain in forests of different maturity in southern China.

    Liang, Guohua; Liu, Xingzhao; Chen, Xiaomei; Qiu, Qingyan; Zhang, Deqiang; Chu, Guowei; Liu, Juxiu; Liu, Shizhong; Zhou, Guoyi

    2013-01-01

    The response of soil respiration to acid rain in forests, especially in forests of different maturity, is poorly understood in southern China despite the fact that acid rain has become a serious environmental threat in this region in recent years. Here, we investigated this issue in three subtropical forests of different maturity [i.e. a young pine forest (PF), a transitional mixed conifer and broadleaf forest (MF) and an old-growth broadleaved forest (BF)] in southern China. Soil respiration was measured over two years under four simulated acid rain (SAR) treatments (CK, the local lake water, pH 4.5; T1, water pH 4.0; T2, water pH 3.5; and T3, water pH 3.0). Results indicated that SAR did not significantly affect soil respiration in the PF, whereas it significantly reduced soil respiration in the MF and the BF. The depressed effects on both forests occurred mostly in the warm-wet seasons and were correlated with a decrease in soil microbial activity and in fine root biomass caused by soil acidification under SAR. The sensitivity of the response of soil respiration to SAR showed an increasing trend with the progressive maturity of the three forests, which may result from their differences in acid buffering ability in soil and in litter layer. These results indicated that the depressed effect of acid rain on soil respiration in southern China may be more pronounced in the future in light of the projected change in forest maturity. However, due to the nature of this field study with chronosequence design and the related pseudoreplication for forest types, this inference should be read with caution. Further studies are needed to draw rigorous conclusions regarding the response differences among forests of different maturity using replicated forest types.

  19. Temperature response of respiration across heterogeneous microtopography in the Arctic tundra, Utqiaġvik, Alaska

    Wilkman, E.; Zona, D.; Tang, Y.; Gioli, B.; Lipson, D.; Oechel, W. C.

    2017-12-01

    The response of ecosystem respiration to warming in the Arctic is not well constrained, partly due to the presence of ice-wedge polygons in continuous permafrost areas. These formations lead to substantial variation in vegetation, soil moisture, water table, and active layer depth over the meter scale that can drive respiratory carbon loss. Accurate calculations of in-situ temperature sensitivities (Q10) are vital for the prediction of future Arctic emissions, and while the eddy covariance technique has commonly been used to determine the diurnal and season patterns of net ecosystem exchange (NEE) of CO2, the lack of suitable dark periods in the Arctic summer has limited our ability to estimate and interpret ecosystem respiration. To therefore improve our understanding of and define controls on ecosystem respiration, we directly compared CO2 fluxes measured from automated chambers across the main local polygonised landscape forms (high and low centers, polygon rims, and polygon troughs) to estimates from an adjacent eddy covariance tower. Low-centered polygons and polygon troughs had the greatest cumulative respiration rates, and ecosystem type appeared to be the most important explanatory variable for these rates. Despite the difference in absolute respiration rates, Q10 was surprisingly similar across all microtopographic features, despite contrasting water levels and vegetation types. Conversely, Q10 varied temporally, with higher values during the early and late summer and lower values during the peak growing season. Finally, good agreement was found between chamber and tower based Q10 estimates during the peak growing season. Overall, this study suggests that it is possible to simplify estimates of the temperature sensitivity of respiration across heterogeneous landscapes, but that seasonal changes in Q10 should be incorporated into current and future model simulations.

  20. Design of Kalman filters for mobile robots

    Larsen, Thomas Dall; Hansen, Karsten L.; Andersen, Nils Axel

    1999-01-01

    the mobile robot is equipped with a dual encoder system supported by some additional absolute measurements. A common filter type for this setup is the odometric filter, where readings from the odometry system on the robot are used together with the geometry of the robot movement as a model of the robot......Kalman filters have for a long time been widely used on mobile robots as a location estimator. Many different Kalman filter designs have been proposed, using models of various complexity. In this paper, two different design methods are evaluated and compared. Focus is put on the common setup where...... estimates. The Kalman filter normally consists of a time update followed by one or more data updates. However, it is shown that when using the kinematic filter, the encoder measurements should be fused prior to the time update for better performance....

  1. Filtering the “News” : Uncovering Morphine's Multiple Meanings on Delpher’s Dutch Newspapers and the Need to Distinguish More Article Types

    Walma, L.W.B.

    2015-01-01

    The current categorization of digitized newspaper archives prevents optimal use of the range of newspaper article types. Drawing examples from close reading research into the reputation of morphine in Dutch newspapers from 1880-1914, this article discusses how further specifying the article types

  2. Frost Induces Respiration and Accelerates Carbon Depletion in Trees.

    Or Sperling

    Full Text Available Cellular respiration depletes stored carbohydrates during extended periods of limited photosynthesis, e.g. winter dormancy or drought. As respiration rate is largely a function of temperature, the thermal conditions during such periods may affect non-structural carbohydrate (NSC availability and, ultimately, recovery. Here, we surveyed stem responses to temperature changes in 15 woody species. For two species with divergent respirational response to frost, P. integerrima and P. trichocarpa, we also examined corresponding changes in NSC levels. Finally, we simulated respiration-induced NSC depletion using historical temperature data for the western US. We report a novel finding that tree stems significantly increase respiration in response to near freezing temperatures. We observed this excess respiration in 13 of 15 species, deviating 10% to 170% over values predicted by the Arrhenius equation. Excess respiration persisted at temperatures above 0 °C during warming and reoccurred over multiple frost-warming cycles. A large adjustment of NSCs accompanied excess respiration in P. integerrima, whereas P. trichocarpa neither excessively respired nor adjusted NSCs. Over the course of the years included in our model, frost-induced respiration accelerated stem NSC consumption by 8.4 mg (glucose eq. cm(-3 yr(-1 on average in the western US, a level of depletion that may continue to significantly affect spring NSC availability. This novel finding revises the current paradigm of low temperature respiration kinetics.

  3. Frost Induces Respiration and Accelerates Carbon Depletion in Trees.

    Sperling, Or; Earles, J Mason; Secchi, Francesca; Godfrey, Jessie; Zwieniecki, Maciej A

    2015-01-01

    Cellular respiration depletes stored carbohydrates during extended periods of limited photosynthesis, e.g. winter dormancy or drought. As respiration rate is largely a function of temperature, the thermal conditions during such periods may affect non-structural carbohydrate (NSC) availability and, ultimately, recovery. Here, we surveyed stem responses to temperature changes in 15 woody species. For two species with divergent respirational response to frost, P. integerrima and P. trichocarpa, we also examined corresponding changes in NSC levels. Finally, we simulated respiration-induced NSC depletion using historical temperature data for the western US. We report a novel finding that tree stems significantly increase respiration in response to near freezing temperatures. We observed this excess respiration in 13 of 15 species, deviating 10% to 170% over values predicted by the Arrhenius equation. Excess respiration persisted at temperatures above 0 °C during warming and reoccurred over multiple frost-warming cycles. A large adjustment of NSCs accompanied excess respiration in P. integerrima, whereas P. trichocarpa neither excessively respired nor adjusted NSCs. Over the course of the years included in our model, frost-induced respiration accelerated stem NSC consumption by 8.4 mg (glucose eq.) cm(-3) yr(-1) on average in the western US, a level of depletion that may continue to significantly affect spring NSC availability. This novel finding revises the current paradigm of low temperature respiration kinetics.

  4. A MEMS turbine prototype for respiration harvesting

    Goreke, U.; Habibiabad, S.; Azgin, K.; Beyaz, M. I.

    2015-12-01

    The design, manufacturing, and performance characterization of a MEMS-scale turbine prototype is reported. The turbine is designed for integration into a respiration harvester that can convert normal human breathing into electrical power through electromagnetic induction. The device measures 10 mm in radius, and employs 12 blades located around the turbine periphery along with ball bearings around the center. Finite element simulations showed that an average torque of 3.07 μNm is induced at 12 lpm airflow rate, which lies in normal breathing levels. The turbine and a test package were manufactured using CNC milling on PMMA. Tests were performed at respiration flow rates between 5-25 lpm. The highest rotational speed was measured to be 9.84 krpm at 25 lpm, resulting in 8.96 mbar pressure drop across the device and 370 mW actuation power.

  5. Exposure to respirable crystalline silica in South African farm workers

    Swanepoel, Andrew; Rees, David; Renton, Kevin; Kromhout, Hans

    2009-01-01

    Although listed in some publications as an activity associated with silica (quartz) exposure, agriculture is not widely recognized as an industry with a potential for silica associated diseases. Because so many people work in agriculture; and because silica exposure and silicosis are associated with serious diseases such as tuberculosis (TB), particular in those immunological compromised by the Human immunodeficiency virus (HIV), silica exposure in agriculture is potentially very important. But in South Africa (SA) very little is known about silica exposure in this industry. The objectives of this project are: (a) to measure inhalable and respirable dust and its quartz content on two typical sandy soil farms in the Free State province of SA for all major tasks done on the farms; and (b) to characterise the mineralogy soil type of these farms. Two typical farms in the sandy soil region of the Free State province were studied. The potential health effects faced by these farm workers from exposure to respirable crystalline silica are discussed.

  6. HEPA Filter Vulnerability Assessment

    GUSTAVSON, R.D.

    2000-01-01

    This assessment of High Efficiency Particulate Air (HEPA) filter vulnerability was requested by the USDOE Office of River Protection (ORP) to satisfy a DOE-HQ directive to evaluate the effect of filter degradation on the facility authorization basis assumptions. Within the scope of this assessment are ventilation system HEPA filters that are classified as Safety-Class (SC) or Safety-Significant (SS) components that perform an accident mitigation function. The objective of the assessment is to verify whether HEPA filters that perform a safety function during an accident are likely to perform as intended to limit release of hazardous or radioactive materials, considering factors that could degrade the filters. Filter degradation factors considered include aging, wetting of filters, exposure to high temperature, exposure to corrosive or reactive chemicals, and exposure to radiation. Screening and evaluation criteria were developed by a site-wide group of HVAC engineers and HEPA filter experts from published empirical data. For River Protection Project (RPP) filters, the only degradation factor that exceeded the screening threshold was for filter aging. Subsequent evaluation of the effect of filter aging on the filter strength was conducted, and the results were compared with required performance to meet the conditions assumed in the RPP Authorization Basis (AB). It was found that the reduction in filter strength due to aging does not affect the filter performance requirements as specified in the AB. A portion of the HEPA filter vulnerability assessment is being conducted by the ORP and is not part of the scope of this study. The ORP is conducting an assessment of the existing policies and programs relating to maintenance, testing, and change-out of HEPA filters used for SC/SS service. This document presents the results of a HEPA filter vulnerability assessment conducted for the River protection project as requested by the DOE Office of River Protection

  7. The research of full automatic oil filtering control technology of high voltage insulating oil

    Gong, Gangjun; Zhang, Tong; Yan, Guozeng; Zhang, Han; Chen, Zhimin; Su, Chang

    2017-09-01

    In this paper, the design scheme of automatic oil filter control system for transformer oil in UHV substation is summarized. The scheme specifically includes the typical double tank filter connection control method of the transformer oil of the UHV substation, which distinguishes the single port and the double port connection structure of the oil tank. Finally, the design scheme of the temperature sensor and respirator is given in detail, and the detailed evaluation and application scenarios are given for reference.

  8. Switching non-local vector median filter

    Matsuoka, Jyohei; Koga, Takanori; Suetake, Noriaki; Uchino, Eiji

    2016-04-01

    This paper describes a novel image filtering method that removes random-valued impulse noise superimposed on a natural color image. In impulse noise removal, it is essential to employ a switching-type filtering method, as used in the well-known switching median filter, to preserve the detail of an original image with good quality. In color image filtering, it is generally preferable to deal with the red (R), green (G), and blue (B) components of each pixel of a color image as elements of a vectorized signal, as in the well-known vector median filter, rather than as component-wise signals to prevent a color shift after filtering. By taking these fundamentals into consideration, we propose a switching-type vector median filter with non-local processing that mainly consists of a noise detector and a noise removal filter. Concretely, we propose a noise detector that proactively detects noise-corrupted pixels by focusing attention on the isolation tendencies of pixels of interest not in an input image but in difference images between RGB components. Furthermore, as the noise removal filter, we propose an extended version of the non-local median filter, we proposed previously for grayscale image processing, named the non-local vector median filter, which is designed for color image processing. The proposed method realizes a superior balance between the preservation of detail and impulse noise removal by proactive noise detection and non-local switching vector median filtering, respectively. The effectiveness and validity of the proposed method are verified in a series of experiments using natural color images.

  9. A pilot study of the nocturnal respiration rates in COPD patients in the home environment using a non-contact biomotion sensor

    Ballal, Tarig; Zaffaroni, Alberto; Heneghan, Conor; Shouldice, Redmond; Boyle, Patricia; McNicholas, Walter T; De Chazal, Philip; Donnelly, Seamas C

    2014-01-01

    Nocturnal respiration rate parameters were collected from 20 COPD subjects over an 8 week period, to determine if changes in respiration rate were associated with exacerbations of COPD. These subjects were primarily GOLD Class 2 to 4, and had been recently discharged from hospital following a recent exacerbation. The respiration rates were collected using a non-contact radio-frequency biomotion sensor which senses respiratory effort and body movement using a short-range radio-frequency sensor. An adaptive notch filter was applied to the measured signal to determine respiratory rate over rolling 15 s segments. The accuracy of the algorithm was initially verified using ten manually-scored 15 min segments of respiration extracted from overnight polysomnograms. The calculated respiration rates were within 1 breath min −1 for >98% of the estimates. For the 20 subjects monitored, 11 experienced one or more subsequent exacerbation of COPD (ECOPD) events during the 8 week monitoring period (19 events total). Analysis of the data revealed a significant increase in nocturnal respiration rate (e.g. >2 breath min −1 ) prior to many ECOPD events. Using a simple classifier of a change of 1 breath min −1 in the mode of the nocturnal respiration rate, a predictive rule showed a sensitivity of 63% and specificity of 85% for predicting an exacerbation within a 5 d window. We conclude that it is possible to collect respiration rates reliably in the home environment, and that the respiration rate may be a potential indicator of change in clinical status. (paper)

  10. Adaptive filtering primer with Matlab

    Poularikas, Alexander D

    2006-01-01

    INTRODUCTIONSignal ProcessingAn ExampleOutline of the TextDISCRETE-TIME SIGNAL PROCESSINGDiscrete Time SignalsTransform-Domain Representation of Discrete-Time SignalsThe Z-TransformDiscrete-Time SystemsProblemsHints-Solutions-SuggestionsRANDOM VARIABLES, SEQUENCES, AND STOCHASTIC PROCESSESRandom Signals and DistributionsAveragesStationary ProcessesSpecial Random Signals and Probability Density FunctionsWiener-Khinchin RelationsFiltering Random ProcessesSpecial Types of Random ProcessesNonparametric Spectra EstimationParametric Methods of power Spectral EstimationProblemsHints-Solutions-SuggestionsWIENER FILTERSThe Mean-Square ErrorThe FIR Wiener FilterThe Wiener SolutionWiener Filtering ExamplesProblemsHints-Solutions-SuggestionsEIGENVALUES OF RX - PROPERTIES OF THE ERROR SURFACEThe Eigenvalues of the Correlation MatrixGeometrical Properties of the Error SurfaceProblemsHints-Solutions-SuggestionsNEWTON AND STEEPEST-DESCENT METHODOne-Dimensional Gradient Search MethodSteepest-Descent AlgorithmProblemsHints-Sol...

  11. Bias aware Kalman filters

    Drecourt, J.-P.; Madsen, H.; Rosbjerg, Dan

    2006-01-01

    This paper reviews two different approaches that have been proposed to tackle the problems of model bias with the Kalman filter: the use of a colored noise model and the implementation of a separate bias filter. Both filters are implemented with and without feedback of the bias into the model state....... The colored noise filter formulation is extended to correct both time correlated and uncorrelated model error components. A more stable version of the separate filter without feedback is presented. The filters are implemented in an ensemble framework using Latin hypercube sampling. The techniques...... are illustrated on a simple one-dimensional groundwater problem. The results show that the presented filters outperform the standard Kalman filter and that the implementations with bias feedback work in more general conditions than the implementations without feedback. 2005 Elsevier Ltd. All rights reserved....

  12. Simon-nitinol filter

    Simon, M.; Kim, D.; Porter, D.H.; Kleshinski, S.

    1989-01-01

    This paper discusses a filter that exploits the thermal shape-memory properties of the nitinol alloy to achieve an optimized filter shape and a fine-bore introducer. Experimental methods and materials are given and results are analyzed

  13. MST Filterability Tests

    Poirier, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Duignan, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-03-12

    The Savannah River Site (SRS) is currently treating radioactive liquid waste with the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). The low filter flux through the ARP has limited the rate at which radioactive liquid waste can be treated. Recent filter flux has averaged approximately 5 gallons per minute (gpm). Salt Batch 6 has had a lower processing rate and required frequent filter cleaning. Savannah River Remediation (SRR) has a desire to understand the causes of the low filter flux and to increase ARP/MCU throughput. In addition, at the time the testing started, SRR was assessing the impact of replacing the 0.1 micron filter with a 0.5 micron filter. This report describes testing of MST filterability to investigate the impact of filter pore size and MST particle size on filter flux and testing of filter enhancers to attempt to increase filter flux. The authors constructed a laboratory-scale crossflow filter apparatus with two crossflow filters operating in parallel. One filter was a 0.1 micron Mott sintered SS filter and the other was a 0.5 micron Mott sintered SS filter. The authors also constructed a dead-end filtration apparatus to conduct screening tests with potential filter aids and body feeds, referred to as filter enhancers. The original baseline for ARP was 5.6 M sodium salt solution with a free hydroxide concentration of approximately 1.7 M.3 ARP has been operating with a sodium concentration of approximately 6.4 M and a free hydroxide concentration of approximately 2.5 M. SRNL conducted tests varying the concentration of sodium and free hydroxide to determine whether those changes had a significant effect on filter flux. The feed slurries for the MST filterability tests were composed of simple salts (NaOH, NaNO2, and NaNO3) and MST (0.2 – 4.8 g/L). The feed slurry for the filter enhancer tests contained simulated salt batch 6 supernate, MST, and filter enhancers.

  14. Iodine filters in nuclear installations

    Wilhelm, J.G.

    1982-01-01

    The present report discusses the significance for environmental exposure of the iodine released with the gaseous effluents of nuclear power stations and reprocessing plants in relation to releases of other airborne radionuclides. Iodine filtration processes are described. The release pathways and the composition of airborne fission product iodine mixtures and their bearing on environmental exposure are discussed on the basis of measured fission product iodine emissions. The sorbents which can be used for iodine filtration, their removal efficiencies and range of applications are dealt with in detail. The particular conditions governing iodine removal, which are determined by the various gaseous iodine species, are illustrated on the basis of experimentally determined retention profiles. Particular attention is given to the limitations imposed by temperature, humidity, radiation and filter poisoning. The types of filter normally used are described, their advantages and drawbacks discussed, the principles underlying their design are outlined and the sources of error indicated. The methods normally applied to test the efficiency of various iodine sorbents are described and assessed. Operating experience with iodine filters, gathered from surveillance periods of many years, is supplemented by a large number of test results and the findings of extensive experiments. Possible ways of prolonging the permissible service lives of iodine filters are discussed and information is given on protective measures. The various iodine removal processes applied in reprocessing plants are described and compared with reference to efficiency and cost. The latest developments in filter technology in reprocessing plants are briefly outlined

  15. Intense generation of respirable metal nanoparticles from a low-power soldering unit

    Gómez, Virginia [Department of Chemical Engineering, Nanoscience Institute of Aragon (INA), 50018 Zaragoza (Spain); Irusta, Silvia [Department of Chemical Engineering, Nanoscience Institute of Aragon (INA), 50018 Zaragoza (Spain); Networking Biomedical Research Center of Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 50018 Zaragoza (Spain); Balas, Francisco [Networking Biomedical Research Center of Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 50018 Zaragoza (Spain); Instituto de Carboquímica – Consejo Superior de Investigaciones Científicas (ICB-CSIC), 50018 Zaragoza (Spain); Santamaria, Jesus, E-mail: Jesus.Santamaria@unizar.es [Department of Chemical Engineering, Nanoscience Institute of Aragon (INA), 50018 Zaragoza (Spain); Networking Biomedical Research Center of Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 50018 Zaragoza (Spain)

    2013-07-15

    Highlights: • Intense generation of nanoparticles in the breathing range from a flux-soldering unit is detected. • Coagulation in the aerosol phase leads to 200-nm respirable nanoparticles up to 30 min after operation. • Nanoparticle concentration in the working environment depends on the presence of ambient air. • Metal-containing nanoparticles are collected in TEM grids and filters in the hundreds of nanometer range. -- Abstract: Evidence of intense nanoparticle generation from a low power (45 W) flux soldering unit is presented. This is a familiar device often used in daily life, including home repairs and school electronic laboratories. We demonstrate that metal-containing nanoparticles may reach high concentrations (ca. 10{sup 6} particles/cm{sup 3}) within the breathing range of the operator, with initial size distributions centered at 35–60 nm The morphological and chemical analysis of nanoparticle agglomerates collected on TEM grids and filters confirms their multiparticle structure and the presence of metals.

  16. Intense generation of respirable metal nanoparticles from a low-power soldering unit

    Gómez, Virginia; Irusta, Silvia; Balas, Francisco; Santamaria, Jesus

    2013-01-01

    Highlights: • Intense generation of nanoparticles in the breathing range from a flux-soldering unit is detected. • Coagulation in the aerosol phase leads to 200-nm respirable nanoparticles up to 30 min after operation. • Nanoparticle concentration in the working environment depends on the presence of ambient air. • Metal-containing nanoparticles are collected in TEM grids and filters in the hundreds of nanometer range. -- Abstract: Evidence of intense nanoparticle generation from a low power (45 W) flux soldering unit is presented. This is a familiar device often used in daily life, including home repairs and school electronic laboratories. We demonstrate that metal-containing nanoparticles may reach high concentrations (ca. 10 6 particles/cm 3 ) within the breathing range of the operator, with initial size distributions centered at 35–60 nm The morphological and chemical analysis of nanoparticle agglomerates collected on TEM grids and filters confirms their multiparticle structure and the presence of metals

  17. Evaluation of a treatment system type septic tank - filter anaerobic of upward flow for the residual waters of the ecological benefit of the coffee

    Sanchez C, Jose Alejandro

    1997-01-01

    Colombia is the first country in the production of soft coffee in the world. The benefit for humid way it makes that this quality of coffee is obtained; however, the high consumption of water in the process and the later discharge to the superficial or underground sources, they have generated an environmental problem of great magnitude. Also, the sources of water that they have been contaminated with the discharges of the liquid waste that come from benefit of coffee they present, among other, serious inconveniences to be used as supplying sources of drinkable water. In time of crop, the coffee areas and their superficial sources of water usually register high indexes of contamination like consequence of the discharges of residual waters that come from the benefit of the coffee. In the Departments of Quindio, Valle, Caldas, Antioquia, etc., they have been come executing investigations of the residuals treatment that are derived of the pulp removal of the coffee (via humid), for anaerobic methods with satisfactory results. This project had the collaboration of the Departmental Committee of Coffee of Antioquia and the Environmental Engineering of the Antioquia University and it is formulated toward the evaluation of a Anaerobic filter of Ascendant flow, FAFA, preceded of a septic tank (biological sedimentation), as a treatment system of the coffee residual waters, with a waste native of a ecological benefit area. The obtained results were satisfactory although the generated waste is very intermittent and in times that are not of coffee crop it doesn't take place; what hinders more the application of biological systems for its treatment

  18. High color rendering index of remote-type white LEDs with multi-layered quantum dot-phosphor films and short-wavelength pass dichroic filters

    Yoon, Hee Chang; Oh, Ji Hye; Do, Young Rag

    2014-09-01

    This paper introduces high color rendering index (CRI) white light-emitting diodes (W-LEDs) coated with red emitting (Sr,Ca)AlSiN3:Eu phosphors and yellowish-green emitting AgIn5S8/ZnS (AIS/ZS) quantum dots (QDs) on glass or a short-wavelength pass dichroic filter (SPDF), which transmit blue wavelength regions and reflect yellow wavelength regions. The red emitting (Sr,Ca)AlSiN3:Eu phosphor film is coated on glass and a SPDF using a screen printing method, and then the yellowish-green emitting AIS/ZS QDs are coated on the red phosphor (Sr,Ca)AlSiN3:Eu film-coated glass and SPDF using the electrospray (e-spray) method.To fabricate the red phosphor film, the optimum amount of phosphor is dispersed in a silicon binder to form a red phosphor paste. The AIS/ZS QDs are mixed with dimethylformamide (DMF), toluene, and poly(methyl methacrylate) (PMMA) for the e-spray coating. The substrates are spin-coated with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to fabricate a conductive surface. The CRI of the white LEDs is improved through inserting the red phosphor film between the QD layer and the glass substrate. Furthermore, the light intensities of the multi-layered phosphor films are enhanced through changing the glass substrate to the SPDF. The correlated color temperatures (CCTs) vary as a function of the phosphor concentration in the phosphor paste. The optical properties of the yellowish-green AIS/ZS QDs and red (Sr,Ca)AlSiN3:Eu phosphors are characterized using photoluminescence (PL), and the multi-layered QD-phosphor films are measured using electroluminescence (EL) with an InGaN blue LED (λmax = 450 nm) at 60 mA.

  19. A novel algorithm for determining contact area between a respirator and a headform.

    Lei, Zhipeng; Yang, James; Zhuang, Ziqing

    2014-01-01

    The contact area, as well as the contact pressure, is created when a respiratory protection device (a respirator or surgical mask) contacts a human face. A computer-based algorithm for determining the contact area between a headform and N95 filtering facepiece respirator (FFR) was proposed. Six N95 FFRs were applied to five sizes of standard headforms (large, medium, small, long/narrow, and short/wide) to simulate respirator donning. After the contact simulation between a headform and an N95 FFR was conducted, a contact area was determined by extracting the intersection surfaces of the headform and the N95 FFR. Using computer-aided design tools, a superimposed contact area and an average contact area, which are non-uniform rational basis spline (NURBS) surfaces, were developed for each headform. Experiments that directly measured dimensions of the contact areas between headform prototypes and N95 FFRs were used to validate the simulation results. Headform sizes influenced all contact area dimensions (P contact area dimensions (P contact area, while the large and small headforms produced the smallest.

  20. A remote monitor of bed patient cardiac vibration, respiration and movement.

    Mukai, Koji; Yonezawa, Yoshiharu; Ogawa, Hidekuni; Maki, Hiromichi; Caldwell, W Morton

    2009-01-01

    We have developed a remote system for monitoring heart rate, respiration rate and movement behavior of at-home elderly people who are living alone. The system consists of a 40 kHz ultrasonic transmitter and receiver, linear integrated circuits, a low-power 8-bit single chip microcomputer and an Internet server computer. The 40 kHz ultrasonic transmitter and receiver are installed into a bed mattress. The transmitted signal diffuses into the bed mattress, and the amplitude of the received ultrasonic wave is modulated by the shape of the mattress and parameters such as respiration, cardiac vibration and movement. The modulated ultrasonic signal is received and demodulated by an envelope detection circuit. Low, high and band pass filters separate the respiration, cardiac vibration and movement signals, which are fed into the microcontroller and digitized at a sampling rate of 50 Hz by 8-bit A/D converters. The digitized data are sent to the server computer as a serial signal. This computer stores the data and also creates a graphic chart of the latest hour. The person's family or caregiver can download this chart via the Internet at any time.

  1. Soil texture drives responses of soil respiration to precipitation pulses in the sonoran desert: Implications for climate change

    Cable, J.M.; Ogle, K.; Williams, D.G.; Weltzin, J.F.; Huxman, T. E.

    2008-01-01

    Climate change predictions for the desert southwestern U.S. are for shifts in precipitation patterns. The impacts of climate change may be significant, because desert soil processes are strongly controlled by precipitation inputs ('pulses') via their effect on soil water availability. This study examined the response of soil respiration-an important biological process that affects soil carbon (C) storage-to variation in pulses representative of climate change scenarios for the Sonoran Desert. Because deserts are mosaics of different plant cover types and soil textures-which create patchiness in soil respiration-we examined how these landscape characteristics interact to affect the response of soil respiration to pulses. Pulses were applied to experimental plots of bare and vegetated soil on contrasting soil textures typical of Sonoran Desert grasslands. The data were analyzed within a Bayesian framework to: (1) determine pulse size and antecedent moisture (soil moisture prior to the pulse) effects on soil respiration, (2) quantify soil texture (coarse vs. fine) and cover type (bare vs. vegetated) effects on the response of soil respiration and its components (plant vs. microbial) to pulses, and (3) explore the relationship between long-term variation in pulse regimes and seasonal soil respiration. Regarding objective (1), larger pulses resulted in higher respiration rates, particularly from vegetated fine-textured soil, and dry antecedent conditions amplified respiration responses to pulses (wet antecedent conditions dampened the pulse response). Regarding (2), autotrophic (plant) activity was a significant source (???60%) of respiration and was more sensitive to pulses on coarse- versus fine-textured soils. The sensitivity of heterotrophic (microbial) respiration to pulses was highly dependent on antecedent soil water. Regarding (3), seasonal soil respiration was predicted to increase with both growing season precipitation and mean pulse size (but only for pulses

  2. Plant species richness regulates soil respiration through changes in productivity.

    Dias, André Tavares Corrêa; van Ruijven, Jasper; Berendse, Frank

    2010-07-01

    Soil respiration is an important pathway of the C cycle. However, it is still poorly understood how changes in plant community diversity can affect this ecosystem process. Here we used a long-term experiment consisting of a gradient of grassland plant species richness to test for effects of diversity on soil respiration. We hypothesized that plant diversity could affect soil respiration in two ways. On the one hand, more diverse plant communities have been shown to promote plant productivity, which could increase soil respiration. On the other hand, the nutrient concentration in the biomass produced has been shown to decrease with diversity, which could counteract the production-induced increase in soil respiration. Our results clearly show that soil respiration increased with species richness. Detailed analysis revealed that this effect was not due to differences in species composition. In general, soil respiration in mixtures was higher than would be expected from the monocultures. Path analysis revealed that species richness predominantly regulates soil respiration through changes in productivity. No evidence supporting the hypothesized negative effect of lower N concentration on soil respiration was found. We conclude that shifts in productivity are the main mechanism by which changes in plant diversity may affect soil respiration.

  3. Hyperglycemia induced damage to mitochondrial respiration in renal mesangial and tubular cells: Implications for diabetic nephropathy

    Anna Czajka

    2016-12-01

    Full Text Available Damage to renal tubular and mesangial cells is central to the development of diabetic nephropathy (DN, a complication of diabetes which can lead to renal failure. Mitochondria are the site of cellular respiration and produce energy in the form of ATP via oxidative phosphorylation, and mitochondrial dysfunction has been implicated in DN. Since the kidney is an organ with high bioenergetic needs, we postulated that hyperglycemia causes damage to renal mitochondria resulting in bioenergetic deficit. The bioenergetic profiles and the effect of hyperglycemia on cellular respiration of human primary mesangial (HMCs and proximal tubular cells (HK-2 were compared in normoglycemic and hyperglycemic conditions using the seahorse bio-analyzer. In normoglycemia, HK-2 had significantly lower basal, ATP-linked and maximal respiration rates, and lower reserve capacity compared to HMCs. Hyperglycemia caused a down-regulation of all respiratory parameters within 4 days in HK-2 but not in HMCs. After 8 days of hyperglycemia, down-regulation of respiratory parameters persisted in tubular cells with compensatory up-regulated glycolysis. HMCs had reduced maximal respiration and reserve capacity at 8 days, and by 12 days had compromised mitochondrial respiration despite which they did not enhance glycolysis. These data suggest that diabetes is likely to lead to a cellular deficit in ATP production in both cell types, although with different sensitivities, and this mechanism could significantly contribute to the cellular damage seen in the diabetic kidney. Prevention of diabetes induced damage to renal mitochondrial respiration may be a novel therapeutic approach for the prevention/treatment of DN.

  4. Do traits of invasive species influence decomposition and soil respiration of disturbed ecosystems?

    Wells, A. J.; Balster, N. J.

    2009-12-01

    Large-scale landscape disturbances typically alter the terrestrial carbon cycle leading to shifts in pools of soil carbon. Restoration of disturbed landscapes with prairie vegetation has thus been practiced with the intent of increasing carbon accrual in soils. However, since disturbed soils are prone to invasion by non-native invasive species, many ecological restorations have resulted in unexpected outcomes, which may be explained by differences in plant traits such as tissue quality and biomass allocation. Typically, the tissue of invasive species has lower C:N ratios relative to native species, and consequently, faster decomposition rates, which potentially can alter the balance in soil carbon. The primary objective of this research was to compare the effects of native prairie species versus non-native invasive species on the carbon cycling within a novel environment: a recently dewatered basin in southwestern Wisconsin following dam removal. We hypothesized that a higher invasive to native species ratio would result in faster litter decomposition and a higher rate of soil respiration. To test this hypothesis, we seeded newly exposed sediments with native prairie seeds in 2005, annually collected aboveground plant biomass (by species per plot), calculated decomposition rate of native and invasive litter (underneath both canopy types), and measured soil respiration during the growing season of 2009. After four years of seeding, the aboveground biomass of the native vegetation has increased significantly (p invasive species biomass has decreased from 459 to 296 g m-2. Senesced tissue from mixed native species had a higher C:N ratio, 27:1 (43% C: 1.6% N), than tissue from mixed invasive species, 24:1 (35% C: 1.5% N). However, after 7 months, we found that the rate of decomposition depended on both litter type and plant canopy type (p invasive plant tissue had a slightly faster decomposition rate than the native litter and this rate was elevated under invasive

  5. Rotationally invariant correlation filtering

    Schils, G.F.; Sweeney, D.W.

    1985-01-01

    A method is presented for analyzing and designing optical correlation filters that have tailored rotational invariance properties. The concept of a correlation of an image with a rotation of itself is introduced. A unified theory of rotation-invariant filtering is then formulated. The unified approach describes matched filters (with no rotation invariance) and circular-harmonic filters (with full rotation invariance) as special cases. The continuum of intermediate cases is described in terms of a cyclic convolution operation over angle. The angular filtering approach allows an exact choice for the continuous trade-off between loss of the correlation energy (or specificity regarding the image) and the amount of rotational invariance desired

  6. Retina-Inspired Filter.

    Doutsi, Effrosyni; Fillatre, Lionel; Antonini, Marc; Gaulmin, Julien

    2018-07-01

    This paper introduces a novel filter, which is inspired by the human retina. The human retina consists of three different layers: the Outer Plexiform Layer (OPL), the inner plexiform layer, and the ganglionic layer. Our inspiration is the linear transform which takes place in the OPL and has been mathematically described by the neuroscientific model "virtual retina." This model is the cornerstone to derive the non-separable spatio-temporal OPL retina-inspired filter, briefly renamed retina-inspired filter, studied in this paper. This filter is connected to the dynamic behavior of the retina, which enables the retina to increase the sharpness of the visual stimulus during filtering before its transmission to the brain. We establish that this retina-inspired transform forms a group of spatio-temporal Weighted Difference of Gaussian (WDoG) filters when it is applied to a still image visible for a given time. We analyze the spatial frequency bandwidth of the retina-inspired filter with respect to time. It is shown that the WDoG spectrum varies from a lowpass filter to a bandpass filter. Therefore, while time increases, the retina-inspired filter enables to extract different kinds of information from the input image. Finally, we discuss the benefits of using the retina-inspired filter in image processing applications such as edge detection and compression.

  7. Study of different filters

    Cochinal, R.; Rouby, R.

    1959-01-01

    This note first contains a terminology related to filters and to their operation, and then proposes an overview of general characteristics of filters such as load loss with respect to gas rate, efficiency, and clogging with respect to filter pollution. It also indicates standard aerosols which are generally used, how they are dosed, and how efficiency is determined with a standard aerosol. Then, after a presentation of the filtration principle, this note reports the study of several filters: glass wool, filter papers provided by different companies, Teflon foam, English filters, Teflon wool, sintered Teflonite, quartz wool, polyvinyl chloride foam, synthetic filter, sintered bronze. The third part reports the study of some aerosol and dust separators

  8. Changing ventilation filters

    Hackney, S.

    1980-01-01

    A filter changing unit has a door which interlocks with the door of a filter chamber so as to prevent contamination of the outer surfaces of the doors by radioactive material collected on the filter element and a movable support which enables a filter chamber thereonto to be stored within the unit in such a way that the doors of the unit and the filter chamber can be replaced. The door pivots and interlocks with another door by means of a bolt, a seal around the periphery lip of the first door engages the periphery of the second door to seal the gap. A support pivots into a lower filter element storage position. Inspection windows and glove ports are provided. The unit is releasably connected to the filter chamber by bolts engaging in a flange provided around an opening. (author)

  9. Modeling the filtration ability of stockpiled filtering facepiece

    Rottach, Dana R.

    2016-03-01

    Filtering facepiece respirators (FFR) are often stockpiled for use during public health emergencies such as an infectious disease outbreak or pandemic. While many stockpile administrators are aware of shelf life limitations, environmental conditions can lead to premature degradation. Filtration performance of a set of FFR retrieved from a storage room with failed environmental controls was measured. Though within the expected shelf life, the filtration ability of several respirators was degraded, allowing twice the penetration of fresh samples. The traditional picture of small particle capture by fibrous filter media qualitatively separates the effect of inertial impaction, interception from the streamline, diffusion, settling, and electrostatic attraction. Most of these mechanisms depend upon stable conformational properties. However, common FFR rely on electrets to achieve their high performance, and over time heat and humidity can cause the electrostatic media to degrade. An extension of the Langevin model with correlations to classical filtration concepts will be presented. The new computational model will be used to predict the change in filter effectiveness as the filter media changes with time.

  10. Mathematic filters and digital processing in nuclear medicine

    Dimentein, R.

    1992-01-01

    The mathematic filters used in nuclear medicine were evaluated. Tomographic processing of a Jaszczak phantom, using separately Hanning, Butterworth and Wiener filters were presented. For each type of filter were made simulation, where the cut frequency and extenuation grade values were changed. (C.G.C.)

  11. An optimal filter for short photoplethysmogram signals

    Liang, Yongbo; Elgendi, Mohamed; Chen, Zhencheng; Ward, Rabab

    2018-01-01

    A photoplethysmogram (PPG) contains a wealth of cardiovascular system information, and with the development of wearable technology, it has become the basic technique for evaluating cardiovascular health and detecting diseases. However, due to the varying environments in which wearable devices are used and, consequently, their varying susceptibility to noise interference, effective processing of PPG signals is challenging. Thus, the aim of this study was to determine the optimal filter and filter order to be used for PPG signal processing to make the systolic and diastolic waves more salient in the filtered PPG signal using the skewness quality index. Nine types of filters with 10 different orders were used to filter 219 (2.1s) short PPG signals. The signals were divided into three categories by PPG experts according to their noise levels: excellent, acceptable, or unfit. Results show that the Chebyshev II filter can improve the PPG signal quality more effectively than other types of filters and that the optimal order for the Chebyshev II filter is the 4th order. PMID:29714722

  12. Forest Ecosystem respiration estimated from eddy covariance and chamber measurements under high turbulence and substantial tree mortality from bark beetles

    Speckman, Heather N.; Frank, John M.; Bradford, John B.; Miles, Brianna L.; Massman, William J.; Parton, William J.; Ryan, Michael G.

    2015-01-01

    Eddy covariance nighttime fluxes are uncertain due to potential measurement biases. Many studies report eddy covariance nighttime flux lower than flux from extrapolated chamber measurements, despite corrections for low turbulence. We compared eddy covariance and chamber estimates of ecosystem respiration at the GLEES Ameriflux site over seven growing seasons under high turbulence (summer night mean friction velocity (u*) = 0.7 m s−1), during which bark beetles killed or infested 85% of the aboveground respiring biomass. Chamber-based estimates of ecosystem respiration during the growth season, developed from foliage, wood and soil CO2 efflux measurements, declined 35% after 85% of the forest basal area had been killed or impaired by bark beetles (from 7.1 ±0.22 μmol m−2 s−1 in 2005 to 4.6 ±0.16 μmol m−2 s−1 in 2011). Soil efflux remained at ~3.3 μmol m−2 s−1 throughout the mortality, while the loss of live wood and foliage and their respiration drove the decline of the chamber estimate. Eddy covariance estimates of fluxes at night remained constant over the same period, ~3.0 μmol m−2 s−1 for both 2005 (intact forest) and 2011 (85% basal area killed or impaired). Eddy covariance fluxes were lower than chamber estimates of ecosystem respiration (60% lower in 2005, and 32% in 2011), but the mean night estimates from the two techniques were correlated within a year (r2 from 0.18-0.60). The difference between the two techniques was not the result of inadequate turbulence, because the results were robust to a u* filter of > 0.7 m s−1. The decline in the average seasonal difference between the two techniques was strongly correlated with overstory leaf area (r2=0.92). The discrepancy between methods of respiration estimation should be resolved to have confidence in ecosystem carbon flux estimates.

  13. Glycolysis and mitochondrial respiration in mouse LDHC-null sperm.

    Odet, Fanny; Gabel, Scott; London, Robert E; Goldberg, Erwin; Eddy, Edward M

    2013-04-01

    We demonstrated previously that a knockout (KO) of the lactate dehydrogenase type C (Ldhc) gene disrupted male fertility and caused a considerable reduction in sperm glucose consumption, ATP production, and motility. While that study used mice with a mixed genetic background, the present study used C57BL/6 (B6) and 129S6 (129) Ldhc KO mice. We found that B6 KO males were subfertile and 129 KO males were infertile. Sperm from 129 wild-type (WT) mice have a lower glycolytic rate than sperm from B6 WT mice, resulting in a greater reduction in ATP production in 129 KO sperm than in B6 KO sperm. The lower glycolytic rate in 129 sperm offered a novel opportunity to examine the role of mitochondrial respiration in sperm ATP production and motility. We observed that in media containing a mitochondrial substrate (pyruvate or lactate) as the sole energy source, ATP levels and progressive motility in 129 KO sperm were similar to those in 129 WT sperm. However, when glucose was added, lactate was unable to maintain ATP levels or progressive motility in 129 KO sperm. The rate of respiration (ZO2) was high when 129 KO or WT sperm were incubated with lactate alone, but addition of glucose caused a reduction in ZO2. These results indicate that in the absence of glucose, 129 sperm can produce ATP via oxidative phosphorylation, but in the presence of glucose, oxidative phosphorylation is suppressed and the sperm utilize aerobic glycolysis, a phenomenon known as the Crabtree effect.

  14. UV Fluorescence Photography of Works of Art : Replacing the Traditional UV Cut Filters with Interference Filters

    Luís BRAVO PEREIRA

    2010-09-01

    Full Text Available For many years filters like the Kodak Wratten E series, or the equivalent Schneider B+W 415, were used as standard UV cut filters, necessary to obtain good quality on UV Fluorescence photography. The only problem with the use of these filters is that, when they receive the UV radiation that they should remove, they present themselves an internal fluorescence as side effect, that usually reduce contrast and quality on the final image. This article presents the results of our experiences on using some innovative filters, that appeared available on the market in recent years, projected to adsorb UV radiation even more efficiently than with the mentioned above pigment based standard filters: the interference filters for UV rejection (and, usually, for IR rejection too manufactured using interference layers, that present better results than the pigment based filters. The only problem with interference filters type is that they are sensitive to the rays direction and, because of that, they are not adequate to wide-angle lenses. The internal fluorescence for three filters: the B+W 415 UV cut (equivalent to the Kodak Wratten 2E, pigment based, the B+W 486 UV IR cut (an interference type filter, used frequently on digital cameras to remove IR or UV and the Baader UVIR rejection filter (two versions of this interference filter were used had been tested and compared. The final quality of the UV fluorescence images seems to be of a superior quality when compared to the images obtained with classic filters.

  15. Partitioning of ecosystem respiration in a beech forest

    Brændholt, Andreas; Ibrom, Andreas; Larsen, Klaus Steenberg

    2018-01-01

    Terrestrial ecosystem respiration (Reco) represents a major component of the global carbon cycle. It consists of many sub-components, such as aboveground plant respiration and belowground root and microbial respiration, each of which may respond differently to abiotic factors, and thus to global...... of Reco in a temperate beech forest at diel, seasonal and annual time scales. Reco was measured by eddy covariance while respiration rates from soil, tree stems and isolated coarse tree roots were measured bi-hourly by an automated closed-chamber system. Soil respiration (Rsoil) was measured in intact...... plots, and heterotrophic Rsoil was measured in trenched plots. Tree stem (Rstem) and coarse root (Rroot) respiration were measured by custom made closed-chambers. We found that the contribution of Rstem to total Reco varied across the year, by only accounting for 6% of Reco during winter and 16% during...

  16. Role of the supX gene in sensitizing Salmonella typhimurium cells to respiration shutoff induced by far ultraviolet irradiation

    Swenson, P.A.; Riester, L.; Palmer, T.V.

    1983-01-01

    Salmonella typhimurium strains with supX mutations are known to be sensitive to UV (254 nm) irradiation and to be protected by plasmid pKM101. Wild type (supX + ) cells shut off their respiration after UV and are protected against their shutoff by pKM101. Respiration and survival studies were carried out on several supX strains. The supX strains shut off their respiration after low fluences of UV. Plasmid pKM101 protected a supX83 (nonsense mutation) strain against respiration shutoff and killing but did not protect a supX35 (deletion mutation) strain. When each of the two supX genes were in the genetic backgrounds of the other, however, full protection was provided by pKM101. The supX35 strain not protected by pKM101 may have accumulated a modifying mutation. The supX locus is identical with one specifying topoisomerase I which removes negative superhelical turns from DNA. In the absence of this enzyme, transcription of the DNA is increased. It is proposed that the exaggerated shutoff of respiration and increased killing of supX cells occurs because of the greater ease of transcription of an operon involved in UV-induced respiration shutoff. (author)

  17. Maintenance, endogeneous, respiration, lysis, decay and predation

    loosdrecht, Marc C. M. Van; Henze, Mogens

    1999-01-01

    mechanism is microbiologically correct. The lysis/decay model mechanism is a strongly simplified representation of reality. This paper tries to review the processes grouped under endogenous respiration in activated sludge models. Mechanisms and processes such as maintenance, lysis, internal and external...... decay, predation and death-regeneration are discussed. From recent microbial research it has become evident that cells do not die by themselves. Bacteria are however subject to predation by protozoa. Bacteria store reserve polymers that in absence of external substrate are used for growth...

  18. Optimum filters for narrow-band frequency modulation.

    Shelton, R. D.

    1972-01-01

    The results of a computer search for the optimum type of bandpass filter for low-index angle-modulated signals are reported. The bandpass filters are discussed in terms of their low-pass prototypes. Only filter functions with constant numerators are considered. The pole locations for the optimum filters of several cases are shown in a table. The results are fairly independent of modulation index and bandwidth.

  19. Noise Reduction of Measurement Data using Linear Digital Filters

    Hitzmann B.

    2007-12-01

    Full Text Available In this paper Butterworth, Chebyshev (Type I and II and Elliptic digital filters are designed for signal noise reduction. On-line data measurements of substrate concentration from E. coli fed-batch cultivation process are used. Application of the designed filters leads to a successful noise reduction of on-line glucose measurements. The digital filters presented here are simple, easy to implement and effective - the used filters allow for a smart compromise between signal information and noise corruption.

  20. Contribution of root respiration to soil respiration in a C3/C4 mixed ...

    Unknown

    The linear regression relationship between soil respiration and root biomass was used to determine the .... 10 days, sieved 50 g soil samples were placed in a 100 ml beaker and a 250 ..... Comparatively, the method can take multi-samples by ...

  1. ESTIMATING ROOT RESPIRATION IN SPRUCE AND BEECH: DECREASES IN SOIL RESPIRATION FOLLOWING GIRDLING

    A study was undertaken to follow seasonal fluxes of CO2 from soil and to estimate the contribution of autotrophic (root + mycorrhizal) to total soil respiration (SR) in a mixed stand of European beech (Fagus sylvatica) and Norway spruce (Picea abies) near Freising, Germany. Matu...

  2. Filter material charging apparatus for filter assembly for radioactive contaminants

    Goldsmith, J.M.; O'Nan, A. Jr.

    1977-01-01

    A filter charging apparatus for a filter assembly is described. The filter assembly includes a housing with at least one filter bed therein and the filter charging apparatus for adding filter material to the filter assembly includes a tank with an opening therein, the tank opening being disposed in flow communication with opposed first and second conduit means, the first conduit means being in flow communication with the filter assembly housing and the second conduit means being in flow communication with a blower means. Upon activation of the blower means, the blower means pneumatically conveys the filter material from the tank to the filter housing

  3. Evaluation of self-contained HEPA filter

    Arndt, T.E. [Westinghouse Hanford Company, Richland, WA (United States)

    1995-02-01

    This paper presents the results of an evaluation of a self-contained high-efficiency particulate air filter (SHEPA) used in nuclear applications. A SCHEPA consists of filter medium encapsulated in a casing that is part of the system boundary. The SCHEPA filter serves as a combination of filter housing and filter. The filter medium is attached directly to the casing using adhesive as a bonding agent. A cylindrical connection in the middle of the end caps connects the filter assembly to adjoining ductwork. The SCHEPA must perform the functions of a filter housing, filter frame, and filter. It was recognized that the codes and standards do not address the SCHEPA specifically. Therefore, the investigation evaluated the SCHEPA against current codes and standards related to the functional requirements of an air-cleaning system. The specific standards used are required by DOE Order 6430.1A{sup 1} and include ASME N509{sup 3}, ASME N510{sup 4}, ERDA 76-21{sup 5}, MIL-F-51068F{sup 6}, NFPA 90A, {sup 7} and NFPA 91{sup 8}. The evaluation does not address whether the SCHEPA as a standard (off-the-shelf) filter could be upgraded to meet the current code requirements for an air-cleaning unit. The evaluation also did not consider how the SCHEPA was used in a system (e.g., whether it was under positive or negative pressure or whether it served as an air inlet filter to prevent contamination releases under system pressurization). The results of the evaluation show that, the SCHEPA filter does not meet design, fabrication, testing, and documentation requirements of ASME N509{sup 3} and ASME N510{sup 4}. The paper will identify these deficiencies. Specific exhaust system requirements and application should be considered when an evaluation of the SCHEPA filter is being performed in existing systems. When new designs are being comtemplated, other types of HEPA filter housings can be used in lieu of the SCHEPA filter.

  4. [The development of a respiration and temperature monitor].

    Du, X; Wu, B; Liu, Y; He, Q; Xiao, J

    2001-12-01

    This paper introduces the design of a monitoring system to measure the respiration and temperature of a body with an 8Xc196 single-chip microcomputer. This system can measure and display the respiration wave, respiration frequency and the body temperature in real-time with a liquid crystal display (LCD) and give an alarm when the parameters are beyond the normal scope. In addition, this device can provide a 24 hours trend graph of the respiration frequency and the body temperature parameters measured. Data can also be exchanged through serial communication interfaces (RS232) between the PC and the monitor.

  5. Minimal incorporation of Deepwater Horizon oil by estuarine filter feeders

    Fry, Brian; Anderson, Laurie C.

    2014-01-01

    Highlights: • Oil from the Deepwater Horizon oil spill entered Louisiana bays in mid-2010. • Oil was used minimally (<1%) in diets of mussels and barnacles. • Also, oil did not enhance planktonic respiration rates. • Use of oil carbon was relatively small in these productive estuarine food webs. - Abstract: Natural abundance carbon isotope analyses are sensitive tracers for fates and use of oil in aquatic environments. Use of oil carbon in estuarine food webs should lead to isotope values approaching those of oil itself, −27‰ for stable carbon isotopes reflecting oil origins and −1000‰ for carbon-14 reflecting oil age. To test for transfer of oil from the 2010 Deepwater Horizon spill into estuarine food webs, filter-feeding barnacles (Balanus sp.) and marsh mussels (Geukensia demissa) were collected from Louisiana estuaries near the site of the oil spill. Carbon-14 analyses of these animals from open waters and oiled marshes showed that oil use was <1% and near detection limits estimated at 0.3% oil incorporation. Respiration studies showed no evidence for enhanced microbial activity in bay waters. Results are consistent with low dietary impacts of oil for filter feeders and little overall impact on respiration in the productive Louisiana estuarine systems

  6. The second order extended Kalman filter and Markov nonlinear filter for data processing in interferometric systems

    Ermolaev, P; Volynsky, M

    2014-01-01

    Recurrent stochastic data processing algorithms using representation of interferometric signal as output of a dynamic system, which state is described by vector of parameters, in some cases are more effective, compared with conventional algorithms. Interferometric signals depend on phase nonlinearly. Consequently it is expedient to apply algorithms of nonlinear stochastic filtering, such as Kalman type filters. An application of the second order extended Kalman filter and Markov nonlinear filter that allows to minimize estimation error is described. Experimental results of signals processing are illustrated. Comparison of the algorithms is presented and discussed.

  7. Respirator studies for the ERDA Division of Safety, Standards, and Compliance. Progress report, July 1, 1974--June 30, 1975

    Douglas, D.D.; Hack, A.L.; Davis, T.O.; Shafer, C.; Moore, T.O.; Richards, C.P.; Revoir, W.H.

    1976-08-01

    Major accomplishments during FY 1975 were the initiation of a respirator research program to investigate the physiological effects of wearing a respirator under stress, assisting ERDA contractors by providing information and training concerning respirator programs, quality assurance of respirators, and respirator applications. A newsletter of respirator developments for ERDA contractor personnel was published, and a Respirator Symposium was conducted

  8. Can we distinguish autotrophic respiration from heterotrophic respiration in a field site using high temporal resolution CO2 flux measurements?

    Biro, Beatrice; Berger, Sina; Praetzel, Leandra; Blodau, Christian

    2016-04-01

    The processes behind C-cycling in peatlands are important to understand for assessing the vulnerability of peatlands as carbon sinks under changing climate conditions. Especially boreal peatlands are likely to underlie strong alterations in the future. It is expected that C-pools that are directly influenced by vegetation and water table fluctuations can be easily destabilized. The CO2 efflux through respiration underlies autotrophic and heterotrophic processes that show different feedbacks on changing environmental conditions. In order to understand the respiration fluxes better for more accurate modelling and prognoses, the determination of the relative importance of different respiration sources is necessary. Earlier studies used e.g. exfoliation experiments, incubation experiments or modelling approaches to estimate the different respiration sources for the total ecosystem respiration (Reco). To further the understanding in this topic, I want to distinguish autotrophic and heterotrophic respiration using high temporal resolution measurements. The study site was selected along a hydrological gradient in a peatland in southern Ontario (Canada) and measurements were conducted from May to September 2015 once per month. Environmental controls (water table, soil temperature and soil moisture) that effect the respiration sources were recorded. In my study I used a Li-COR 6400XT and a Los Gatos greenhouse gas analyzer (GGA). Reco was determined by chamber flux measurements with the GGA, while simultaneously CO2 respiration measurements on different vegetation compartments like roots, leaves and mosses were conducted using the Li-COR 6400XT. The difference between Reco and autotrophic respiration equals heterotrophic respiration. After the measurements, the vegetation plots were harvested and separated for all compartments (leaves, roots, mosses, soil organic matter), dried and weighed. The weighted respiration rates from all vegetation compartments sum up to

  9. Concentric Split Flow Filter

    Stapleton, Thomas J. (Inventor)

    2015-01-01

    A concentric split flow filter may be configured to remove odor and/or bacteria from pumped air used to collect urine and fecal waste products. For instance, filter may be designed to effectively fill the volume that was previously considered wasted surrounding the transport tube of a waste management system. The concentric split flow filter may be configured to split the air flow, with substantially half of the air flow to be treated traveling through a first bed of filter media and substantially the other half of the air flow to be treated traveling through the second bed of filter media. This split flow design reduces the air velocity by 50%. In this way, the pressure drop of filter may be reduced by as much as a factor of 4 as compare to the conventional design.

  10. Efficient Implementation of Complex Modulated Filter Banks Using Cosine and Sine Modulated Filter Banks

    Viholainen Ari

    2006-01-01

    Full Text Available The recently introduced exponentially modulated filter bank (EMFB is a -channel uniform, orthogonal, critically sampled, and frequency-selective complex modulated filter bank that satisfies the perfect reconstruction (PR property if the prototype filter of an -channel PR cosine modulated filter bank (CMFB is used. The purpose of this paper is to present various implementation structures for the EMFBs in a unified framework. The key idea is to use cosine and sine modulated filter banks as building blocks and, therefore, polyphase, lattice, and extended lapped transform (ELT type of implementation solutions are studied. The ELT-based EMFBs are observed to be very competitive with the existing modified discrete Fourier transform filter banks (MDFT-FBs when comparing the number of multiplications/additions and the structural simplicity. In addition, EMFB provides an alternative channel stacking arrangement that could be more natural in certain subband processing applications and data transmission systems.

  11. Filtering Photogrammetric Point Clouds Using Standard LIDAR Filters Towards DTM Generation

    Zhang, Z.; Gerke, M.; Vosselman, G.; Yang, M. Y.

    2018-05-01

    Digital Terrain Models (DTMs) can be generated from point clouds acquired by laser scanning or photogrammetric dense matching. During the last two decades, much effort has been paid to developing robust filtering algorithms for the airborne laser scanning (ALS) data. With the point cloud quality from dense image matching (DIM) getting better and better, the research question that arises is whether those standard Lidar filters can be used to filter photogrammetric point clouds as well. Experiments are implemented to filter two dense matching point clouds with different noise levels. Results show that the standard Lidar filter is robust to random noise. However, artefacts and blunders in the DIM points often appear due to low contrast or poor texture in the images. Filtering will be erroneous in these locations. Filtering the DIM points pre-processed by a ranking filter will bring higher Type II error (i.e. non-ground points actually labelled as ground points) but much lower Type I error (i.e. bare ground points labelled as non-ground points). Finally, the potential DTM accuracy that can be achieved by DIM points is evaluated. Two DIM point clouds derived by Pix4Dmapper and SURE are compared. On grassland dense matching generates points higher than the true terrain surface, which will result in incorrectly elevated DTMs. The application of the ranking filter leads to a reduced bias in the DTM height, but a slightly increased noise level.

  12. Nrf2 impacts cellular bioenergetics by controlling substrate availability for mitochondrial respiration

    Kira M. Holmström

    2013-06-01

    Transcription factor Nrf2 and its repressor Keap1 regulate a network of cytoprotective genes involving more than 1% of the genome, their best known targets being drug-metabolizing and antioxidant genes. Here we demonstrate a novel role for this pathway in directly regulating mitochondrial bioenergetics in murine neurons and embryonic fibroblasts. Loss of Nrf2 leads to mitochondrial depolarisation, decreased ATP levels and impaired respiration, whereas genetic activation of Nrf2 increases the mitochondrial membrane potential and ATP levels, the rate of respiration and the efficiency of oxidative phosphorylation. We further show that Nrf2-deficient cells have increased production of ATP in glycolysis, which is then used by the F1Fo-ATPase for maintenance of the mitochondrial membrane potential. While the levels and in vitro activities of the respiratory complexes are unaffected by Nrf2 deletion, their activities in isolated mitochondria and intact live cells are substantially impaired. In addition, the rate of regeneration of NADH after inhibition of respiration is much slower in Nrf2-knockout cells than in their wild-type counterparts. Taken together, these results show that Nrf2 directly regulates cellular energy metabolism through modulating the availability of substrates for mitochondrial respiration. Our findings highlight the importance of efficient energy metabolism in Nrf2-mediated cytoprotection.

  13. Contribution of Cell Elongation to the Biofilm Formation of Pseudomonas aeruginosa during Anaerobic Respiration

    Park, Yongjin; Yoon, Sang Sun

    2011-01-01

    Pseudomonas aeruginosa, a gram-negative bacterium of clinical importance, forms more robust biofilm during anaerobic respiration, a mode of growth presumed to occur in abnormally thickened mucus layer lining the cystic fibrosis (CF) patient airway. However, molecular basis behind this anaerobiosis-triggered robust biofilm formation is not clearly defined yet. Here, we identified a morphological change naturally accompanied by anaerobic respiration in P. aeruginosa and investigated its effect on the biofilm formation in vitro. A standard laboratory strain, PAO1 was highly elongated during anaerobic respiration compared with bacteria grown aerobically. Microscopic analysis demonstrated that cell elongation likely occurred as a consequence of defective cell division. Cell elongation was dependent on the presence of nitrite reductase (NIR) that reduces nitrite (NO2 −) to nitric oxide (NO) and was repressed in PAO1 in the presence of carboxy-PTIO, a NO antagonist, demonstrating that cell elongation involves a process to respond to NO, a spontaneous byproduct of the anaerobic respiration. Importantly, the non-elongated NIR-deficient mutant failed to form biofilm, while a mutant of nitrate reductase (NAR) and wild type PAO1, both of which were highly elongated, formed robust biofilm. Taken together, our data reveal a role of previously undescribed cell biological event in P. aeruginosa biofilm formation and suggest NIR as a key player involved in such process. PMID:21267455

  14. Adhesion of the clay minerals montmorillonite, kaolinite, and attapulgite reduces respiration of Histoplasma capsulatum.

    Lavie, S; Stotzky, G

    1986-01-01

    The respiration of three phenotypes of Histoplasma capsulatum, the causal agent of histoplasmosis in humans, was markedly reduced by low concentrations of montmorillonite but was reduced less by even higher concentrations of kaolinite or attapulgite (palygorskite). The reduction in respiration followed a pattern that suggested saturation-type kinetics: an initial sharp reduction that occurred with low concentrations of clay (0.01 to 0.5% [wt/vol]), followed by a more gradual reduction with higher concentrations (1 to 8%). Increases in viscosity (which could impair the movement of O2) caused by the clays were not responsible for the reduction in respiration, and the clays did not interfere with the availability of nutrients. Scanning electron microscopy after extensive washing showed that the clay particles were tightly bound to the hyphae, suggesting that the clays reduced the rate of respiration of H. capsulatum by adhering to the mycelial surface and, thereby, interfered with the movement of nutrients, metabolites, and gases across the mycelial wall.

  15. Hybrid Filter Membrane

    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

  16. Backflushable filter insert

    Keith, R.C.; Vandenberg, T.; Randolph, M.C.; Lewis, T.B.; Gillis, P.J. Jr.

    1988-01-01

    Filter elements are mounted on a tube plate beneath an accumulator chamber whose wall is extended by skirt and flange to form a closure for the top of pressure vessel. The accumulator chamber is annular around a central pipe which serves as the outlet for filtered water passing from the filter elements. The chamber contains filtered compressed air from supply. Periodically the filtration of water is stopped and vessel is drained. Then a valve is opened, allowing the accumulated air to flow from chamber up a pipe and down pipe, pushing the filtered water from pipe back through the filter elements to clean them. The accumulator chamber is so proportioned, relative to the volume of the system communicating therewith during backflushing, that the equilibrium pressure during backflushing cannot exceed the pressure rating of the vessel. However a line monitors the pressure at the top of the vessel, and if it rises too far a bleed valve is automatically opened to depressurise the system. The chamber is intended to replace the lid of an existing vessel to convert a filter using filter aid to one using permanent filter elements. (author)

  17. Updating the OMERACT filter

    Wells, George; Beaton, Dorcas E; Tugwell, Peter

    2014-01-01

    The "Discrimination" part of the OMERACT Filter asks whether a measure discriminates between situations that are of interest. "Feasibility" in the OMERACT Filter encompasses the practical considerations of using an instrument, including its ease of use, time to complete, monetary costs......, and interpretability of the question(s) included in the instrument. Both the Discrimination and Reliability parts of the filter have been helpful but were agreed on primarily by consensus of OMERACT participants rather than through explicit evidence-based guidelines. In Filter 2.0 we wanted to improve this definition...

  18. Nanofiber Filters Eliminate Contaminants

    2009-01-01

    With support from Phase I and II SBIR funding from Johnson Space Center, Argonide Corporation of Sanford, Florida tested and developed its proprietary nanofiber water filter media. Capable of removing more than 99.99 percent of dangerous particles like bacteria, viruses, and parasites, the media was incorporated into the company's commercial NanoCeram water filter, an inductee into the Space Foundation's Space Technology Hall of Fame. In addition to its drinking water filters, Argonide now produces large-scale nanofiber filters used as part of the reverse osmosis process for industrial water purification.

  19. Filters in nuclear facilities

    Berg, K.H.; Wilhelm, J.G.

    1985-01-01

    The topics of the nine papers given include the behavior of HEPA filters during exposure to air flows of high humidity as well as of high differential pressure, the development of steel-fiber filters suitable for extreme operating conditions, and the occurrence of various radioactive iodine species in the exhaust air from boiling water reactors. In an introductory presentation the German view of the performance requirements to be met by filters in nuclear facilities as well as the present status of filter quality assurance are discussed. (orig.) [de

  20. Washing method of filter

    Izumidani, Masakiyo; Tanno, Kazuo.

    1978-01-01

    Purpose: To enable automatic filter operation and facilitate back-washing operation by back-washing filters used in a bwr nuclear power plant utilizing an exhaust gas from a ventilator or air conditioner. Method: Exhaust gas from an exhaust pipe of an ventilator or air conditioner is pressurized in a compressor and then introduced in a back-washing gas tank. Then, the exhaust gas pressurized to a predetermined pressure is blown from the inside to the outside of a filter to thereby separate impurities collected on the filter elements and introduce them to a waste tank. (Furukawa, Y.)

  1. Advanced Filter Technology For Nuclear Thermal Propulsion

    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.

  2. Changes in soil respiration after thinning activities in dense Aleppo pine forests

    Llovet, Joan; Alonso, Macià; Cerdà, Artemi

    2015-04-01

    Forest fires are a widespread perturbation in Mediterranean areas, and they have tended to increase during the last decades (Pausas, 2004; Moreno et al, 1998). Aleppo pine (Pinus halepensis Mill) is dominant specie in some forest landscapes of western Mediterranean Basin, due to its capacity to colonize abandoned fields, and also due to afforestation practices mainly performed during the 20th century (Ruiz Navarro et al., 2009). Aleppo pine tends to die as consequence of forest fires, although it is able to disperse a high quantity of seeds which easily germinates. These dispersion and germination can result in dense forests with high inter and intra-specific competition, low diversity, low growth, and high fuel accumulation, increasing the risk of new forest fires. These forests of high density present ecological problems and management difficulties that require preventive treatments. Thinning treatments are common in these types of communities, but the management has to be oriented towards strengthening their functions. In the context of global change, better understandings of the implications of forest management practices in the carbon cycle are necessary. The objective of this study was to examine the evolution of seasonal soil respiration after treatment of selective thinning in dense Aleppo pine forests. The study area covers three localities placed in the Valencian Community (E Spain) affected by a forest fire in 1994. Thinning activities were done 16 years after the fire, reducing pine density from around 100,000 individuals per hectare to around 900 individuals per hectare. Soil respiration was measured in situ with a portable soil respiration instrument (LI-6400, LiCor, Lincoln, NB, USA) fitted with a soil respiration chamber (6400-09, LiCor, Lincoln, NB, USA). We installed 12 plots per treatment (control and thinned) and locality, being a total of 72 plots. We carried out 13 measurements covering a period of one year. We also estimated other related

  3. Comparison of cryogenic low-pass filters

    Thalmann, M.; Pernau, H.-F.; Strunk, C.; Scheer, E.; Pietsch, T.

    2017-11-01

    Low-temperature electronic transport measurements with high energy resolution require both effective low-pass filtering of high-frequency input noise and an optimized thermalization of the electronic system of the experiment. In recent years, elaborate filter designs have been developed for cryogenic low-level measurements, driven by the growing interest in fundamental quantum-physical phenomena at energy scales corresponding to temperatures in the few millikelvin regime. However, a single filter concept is often insufficient to thermalize the electronic system to the cryogenic bath and eliminate spurious high frequency noise. Moreover, the available concepts often provide inadequate filtering to operate at temperatures below 10 mK, which are routinely available now in dilution cryogenic systems. Herein we provide a comprehensive analysis of commonly used filter types, introduce a novel compact filter type based on ferrite compounds optimized for the frequency range above 20 GHz, and develop an improved filtering scheme providing adaptable broad-band low-pass characteristic for cryogenic low-level and quantum measurement applications at temperatures down to few millikelvin.

  4. Comparison of cryogenic low-pass filters.

    Thalmann, M; Pernau, H-F; Strunk, C; Scheer, E; Pietsch, T

    2017-11-01

    Low-temperature electronic transport measurements with high energy resolution require both effective low-pass filtering of high-frequency input noise and an optimized thermalization of the electronic system of the experiment. In recent years, elaborate filter designs have been developed for cryogenic low-level measurements, driven by the growing interest in fundamental quantum-physical phenomena at energy scales corresponding to temperatures in the few millikelvin regime. However, a single filter concept is often insufficient to thermalize the electronic system to the cryogenic bath and eliminate spurious high frequency noise. Moreover, the available concepts often provide inadequate filtering to operate at temperatures below 10 mK, which are routinely available now in dilution cryogenic systems. Herein we provide a comprehensive analysis of commonly used filter types, introduce a novel compact filter type based on ferrite compounds optimized for the frequency range above 20 GHz, and develop an improved filtering scheme providing adaptable broad-band low-pass characteristic for cryogenic low-level and quantum measurement applications at temperatures down to few millikelvin.

  5. Switching non-local median filter

    Matsuoka, Jyohei; Koga, Takanori; Suetake, Noriaki; Uchino, Eiji

    2015-06-01

    This paper describes a novel image filtering method for removal of random-valued impulse noise superimposed on grayscale images. Generally, it is well known that switching-type median filters are effective for impulse noise removal. In this paper, we propose a more sophisticated switching-type impulse noise removal method in terms of detail-preserving performance. Specifically, the noise detector of the proposed method finds out noise-corrupted pixels by focusing attention on the difference between the value of a pixel of interest (POI) and the median of its neighboring pixel values, and on the POI's isolation tendency from the surrounding pixels. Furthermore, the removal of the detected noise is performed by the newly proposed median filter based on non-local processing, which has superior detail-preservation capability compared to the conventional median filter. The effectiveness and the validity of the proposed method are verified by some experiments using natural grayscale images.

  6. Lymphocyte respiration in children with Trisomy 21

    Aburawi Elhadi H

    2012-12-01

    Full Text Available Abstract Background This study measured lymphocyte mitochondrial O2 consumption (cellular respiration in children with trisomy 21. Methods Peripheral blood mononuclear cells were isolated from whole blood of trisomy 21 and control children and these cells were immediately used to measure cellular respiration rate. [O2] was determined as a function of time from the phosphorescence decay rates (1/τ of Pd (II-meso-tetra-(4-sulfonatophenyl-tetrabenzoporphyrin. In sealed vials containing lymphocytes and glucose as a respiratory substrate, [O2] declined linearly with time, confirming the zero-order kinetics of O2 conversion to H2O by cytochrome oxidase. The rate of respiration (k, in μM O2 min-1, thus, was the negative of the slope of [O2] vs. time. Cyanide inhibited O2 consumption, confirming that oxidation occurred in the mitochondrial respiratory chain. Results For control children (age = 8.8 ± 5.6 years, n = 26, the mean (± SD value of kc (in μM O2 per min per 107 cells was 1.36 ± 0.79 (coefficient of variation, Cv = 58%; median = 1.17; range = 0.60 to 3.12; -2SD = 0.61. For children with trisomy 21 (age = 7.2 ± 4.6 years, n = 26, the values of kc were 0.82 ± 0.62 (Cv = 76%; median = 0.60; range = 0.20 to 2.80, pp6.1 mU/L. Fourteen of 26 (54% children with trisomy 21 had kc values of 0.20 to 0.60 (i.e., kc positively correlated with body-mass index (BMI, R >0.302, serum creatinine (R >0.507, blood urea nitrogen (BUN, R >0.535 and albumin (R >0.446. Conclusions Children with trisomy 21 in this study have reduced lymphocyte bioenergetics. The clinical importance of this finding requires further studies.

  7. Impact of a silver layer on the membrane of tap water filters on the microbiological quality of filtered water

    Bruderek Juliane

    2008-10-01

    Full Text Available Abstract Background Bacteria in the hospital's drinking water system represent a risk for the acquisition of a nosocomial infection in the severely immunocompromised host. Terminal tap water filters may be used to prevent nosocomial Legionnaires' disease. We present data from water samples using an improved kind of tap water filters. Methods In a blinded study on an intermediate care unit of the thoracic surgery department, a modified type of the Germlyser water filter (Aqua-Free Membrane Technology with a newly-introduced silver layer on the filtration membrane was compared to its preceding type without such a layer on 15 water outlets. We determined growth of Legionella, other pathogenic bacteria, and the total heterotrophic plate count in unfiltered water and filtered water samples after filter usage intervals of 1 through 4 weeks. Results A total of 299 water samples were tested. Twenty-nine of the 60 unfiltered water samples contained Legionella of various serogroups (baseline value. In contrast, all samples filtered by the original water filter and all but one of the water samples filtered by the modified filter type remained Legionella-free. No other pathogenic bacteria were detected in any filtered sample. The total plate count in water samples increased during use of both kinds of filters over time. However, for the first 7 days of use, there were significantly fewer water samples containing >100 CFU per mL when using the new filter device compared with the older filters or taps with no filter. No advantage was seen thereafter. Conclusion The use of this type of terminal water filter is an appropriate method to protect immunocompromised patients from water-borne pathogens such as Legionella.

  8. Microbial respiration per unit microbial biomass increases with carbon-to-nutrient ratios in soils

    Spohn, Marie; Chodak, Marcin

    2015-04-01

    The ratio of carbon-to-nutrient in forest floors is usually much higher than the ratio of carbon-to-nutrient that soil microorganisms require for their nutrition. In order to understand how this mismatch affects carbon cycling, the respiration rate per unit soil microbial biomass carbon - the metabolic quotient (qCO2) - was studied. This was done in a field study (Spohn and Chodak, 2015) and in a meta-analysis of published data (Spohn, 2014). Cores of beech, spruce, and mixed spruce-beech forest soils were cut into slices of 1 cm from the top of the litter layer down to 5 cm in the mineral soil, and the relationship between the qCO2 and the soil carbon-to-nitrogen (C:N) and the soil carbon-to-phosphorus (C:P) ratio was analyzed. We found that the qCO2 was positively correlated with soil C:N ratio in spruce soils (R = 0.72), and with the soil C:P ratio in beech (R = 0.93), spruce (R = 0.80) and mixed forest soils (R = 0.96). We also observed a close correlation between the qCO2 and the soil C concentration in all three forest types. Yet, the qCO2 decreased less with depth than the C concentration in all three forest types, suggesting that the change in qCO2 is not only controlled by the soil C concentration. We conclude that microorganisms increase their respiration rate per unit biomass with increasing soil C:P ratio and C concentration, which adjusts the substrate to their nutritional demands in terms of stoichiometry. In an analysis of literature data, I tested the effect of the C:N ratio of soil litter layers on microbial respiration in absolute terms and per unit microbial biomass C. For this purpose, a global dataset on the microbial respiration rate per unit microbial biomass C - termed the metabolic quotient (qCO2) - was compiled form literature data. It was found that the qCO2 in the soil litter layers was positively correlated with the litter C:N ratio and negatively related with the litter nitrogen (N) concentration. The positive relation between the qCO2

  9. Soil respiration dynamics in the middle taiga of Central Siberia region

    Makhnykina, Anastasia; Prokushkin, Anatoly; Polosukhina, Daria

    2017-04-01

    A large amount of carbon in soil is released to the atmosphere through soil respiration, which is the main pathway of transferring carbon from terrestrial ecosystems (Comstedt et al., 2011). Considering that boreal forests is a large terrestrial sink (Tans et al., 1990) and represent approximately 11 % of the Earth's total land area (Gower et al., 2001), even a small change in soil respiration could significantly intensify - or mitigate - current atmospheric increases of CO2, with potential feedbacks to climate change. The objectives of the present study are: (a) to study the dynamic of CO2 emission from the soil surface during summer season (from May to October); (b) to identify the reaction of soil respiration to different amount of precipitation as the main limiting factor in the region. The research was located in the pine forests in Central Siberia (60°N, 90°E), Russia. Sample plots were represented by the lichen pine forest, moss pine forest, mixed forest and anthropogenic destroyed area. We used the automated soil CO2 flux system based on the infrared gas analyzer -LI-8100 for measuring the soil efflux. Soil temperature was measured with Soil Temperature Probe Type E in three depths -5, 10, 15 cm. Volumetric soil moisture was measured with Theta Probe Model ML2. The presence and type of ground cover substantially affects the value of soil respiration fluxes. The carbon dioxide emission from the soil surface averaged 5.4 ±2.3 μmol CO2 m-2 s-1. The destroyed area without plant cover demonstrated the lowest soil respiration (0.1-5.6 μmol CO2 m-2 s-1). The lowest soil respiration among forested areas was observed in the feathermoss pine forest. The lichen pine forest was characterized by the intermediate values of soil respiration. The maximum soil respiration values and seasonal fluctuations were obtained in the mixed forest (2.3-29.3 μmol CO2 m-2 s-1). The analysis of relation between soil CO2 efflux and climatic conditions identified the parameters with

  10. Simulation of Human Respiration with Breathing Thermal Manikin

    Bjørn, Erik

    The human respiration contains carbon dioxide, bioeffluents, and perhaps virus or bacteria. People may also indulge in activities that produce contaminants, as for example tobacco smoking. For these reasons, the human respiration remains one of the main contributors to contamination of the indoor...

  11. Interpreting diel hysteresis between soil respiration and temperature

    C. Phillips; N. Nickerson; D. Risk; B.J. Bond

    2011-01-01

    Increasing use of automated soil respiration chambers in recent years has demonstrated complex diel relationships between soil respiration and temperature that are not apparent from less frequent measurements. Soil surface flux is often lagged from soil temperature by several hours, which results in semielliptical hysteresis loops when surface flux is plotted as a...

  12. Differential soil respiration responses to changing hydrologic regimes

    Vincent J. Pacific; Brian L. McGlynn; Diego A. Riveros-Iregui; Howard E. Epstein; Daniel L. Welsch

    2009-01-01

    Soil respiration is tightly coupled to the hydrologic cycle (i.e., snowmelt and precipitation timing and magnitude). We examined riparian and hillslope soil respiration across a wet (2005) and a dry (2006) growing season in a subalpine catchment. When comparing the riparian zones, cumulative CO2 efflux was 33% higher, and peak efflux occurred 17 days earlier during the...

  13. Automatic patient respiration failure detection system with wireless transmission

    Dimeff, J.; Pope, J. M.

    1968-01-01

    Automatic respiration failure detection system detects respiration failure in patients with a surgically implanted tracheostomy tube, and actuates an audible and/or visual alarm. The system incorporates a miniature radio transmitter so that the patient is unencumbered by wires yet can be monitored from a remote location.

  14. Soil respiration response to experimental disturbances over 3 years

    Amy Concilio; Siyan Ma; Soung-Ryoul Ryu; Malcolm North; Jiquan Chen

    2006-01-01

    Soil respiration is a major pathway for carbon cycling in terrestrial ecosystems yet little is known about its response to natural and anthropogenic disturbances. This study examined soil respiration response to prescribed burning and thinning treatments in an old-growth, mixed-conifer forest on the western slope of the Sierra Nevada Mountains. Experimental treatments...

  15. Respirators: Air Purifying, Self-Study, Course 40723

    Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-12-21

    Respirators: Air Purifying Self-Study (COURSE 40723) is designed for Los Alamos National Laboratory (LANL) workers, support services subcontractors, and other LANL subcontractors who work under the LANL Respiratory Protection Program (RPP). This course also meets the air-purifying respirators (APRs) retraining requirement.

  16. Soil Respiration and Student Inquiry: A Perfect Match

    Hoyt, Catherine Marie; Wallenstein, Matthew David

    2011-01-01

    This activity explores the cycling of carbon between the atmosphere (primarily as CO[subscript 2]) and biomass in plants, animals, and microscopic organisms. Students design soil respiration experiments using a protocol that resembles current practice in soil ecology. Three methods for measuring soil respiration are presented. Student-derived…

  17. An adaptive Kalman filter approach for cardiorespiratory signal extraction and fusion of non-contacting sensors.

    Foussier, Jerome; Teichmann, Daniel; Jia, Jing; Misgeld, Berno; Leonhardt, Steffen

    2014-05-09

    Extracting cardiorespiratory signals from non-invasive and non-contacting sensor arrangements, i.e. magnetic induction sensors, is a challenging task. The respiratory and cardiac signals are mixed on top of a large and time-varying offset and are likely to be disturbed by measurement noise. Basic filtering techniques fail to extract relevant information for monitoring purposes. We present a real-time filtering system based on an adaptive Kalman filter approach that separates signal offsets, respiratory and heart signals from three different sensor channels. It continuously estimates respiration and heart rates, which are fed back into the system model to enhance performance. Sensor and system noise covariance matrices are automatically adapted to the aimed application, thus improving the signal separation capabilities. We apply the filtering to two different subjects with different heart rates and sensor properties and compare the results to the non-adaptive version of the same Kalman filter. Also, the performance, depending on the initialization of the filters, is analyzed using three different configurations ranging from best to worst case. Extracted data are compared with reference heart rates derived from a standard pulse-photoplethysmographic sensor and respiration rates from a flowmeter. In the worst case for one of the subjects the adaptive filter obtains mean errors (standard deviations) of -0.2 min(-1) (0.3 min(-1)) and -0.7 bpm (1.7 bpm) (compared to -0.2 min(-1) (0.4 min(-1)) and 42.0 bpm (6.1 bpm) for the non-adaptive filter) for respiration and heart rate, respectively. In bad conditions the heart rate is only correctly measurable when the Kalman matrices are adapted to the target sensor signals. Also, the reduced mean error between the extracted offset and the raw sensor signal shows that adapting the Kalman filter continuously improves the ability to separate the desired signals from the raw sensor data. The average total computational time needed

  18. Bioaerosol Exposure to Filtering Facepiece Respirators in a Clinical Environment (Author’s Final Manuscript)

    2013-03-11

    Stenotrophomonas maltophilia 1 1 unacceptable profile 41 Kocuria kristinae 1 2 3 Kocuria varians/rosea 1 2 1 4 Micrococcus spp 33 1 1 35 Staphylococcus...18/49 (36.7%) 16/49 (32.65%) Kocuria kristinae 2/3 0/3 0/3 Kocuria varians/rosea 2/4 1/4 1/4 Micrococcus spp. 33/35 5/35 5/35 Staphylococcus aureus

  19. Filter forensics: microbiota recovery from residential HVAC filters.

    Maestre, Juan P; Jennings, Wiley; Wylie, Dennis; Horner, Sharon D; Siegel, Jeffrey; Kinney, Kerry A

    2018-01-30

    Establishing reliable methods for assessing the microbiome within the built environment is critical for understanding the impact of biological exposures on human health. High-throughput DNA sequencing of dust samples provides valuable insights into the microbiome present in human-occupied spaces. However, the effect that different sampling methods have on the microbial community recovered from dust samples is not well understood across sample types. Heating, ventilation, and air conditioning (HVAC) filters hold promise as long-term, spatially integrated, high volume samplers to characterize the airborne microbiome in homes and other climate-controlled spaces. In this study, the effect that dust recovery method (i.e., cut and elution, swabbing, or vacuuming) has on the microbial community structure, membership, and repeatability inferred by Illumina sequencing was evaluated. The results indicate that vacuum samples captured higher quantities of total, bacterial, and fungal DNA than swab or cut samples. Repeated swab and vacuum samples collected from the same filter were less variable than cut samples with respect to both quantitative DNA recovery and bacterial community structure. Vacuum samples captured substantially greater bacterial diversity than the other methods, whereas fungal diversity was similar across all three methods. Vacuum and swab samples of HVAC filter dust were repeatable and generally superior to cut samples. Nevertheless, the contribution of environmental and human sources to the bacterial and fungal communities recovered via each sampling method was generally consistent across the methods investigated. Dust recovery methodologies have been shown to affect the recovery, repeatability, structure, and membership of microbial communities recovered from dust samples in the built environment. The results of this study are directly applicable to indoor microbiota studies utilizing the filter forensics approach. More broadly, this study provides a

  20. Respirable dust and quartz exposure from three South African farms with sandy, sandy loam, and clay soils.

    Swanepoel, Andrew J; Kromhout, Hans; Jinnah, Zubair A; Portengen, Lützen; Renton, Kevin; Gardiner, Kerry; Rees, David

    2011-07-01

    To quantify personal time-weighted average respirable dust and quartz exposure on a sandy, a sandy loam, and a clay soil farm in the Free State and North West provinces of South Africa and to ascertain whether soil type is a determinant of exposure to respirable quartz. Three farms, located in the Free State and North West provinces of South Africa, had their soil type confirmed as sandy, sandy loam, and clay; and, from these, a total of 298 respirable dust and respirable quartz measurements were collected between July 2006-November 2009 during periods of major farming operations. Values below the limit of detection (LOD) (22 μg · m(-3)) were estimated using multiple 'imputation'. Non-parametric tests were used to compare quartz exposure from the three different soil types. Exposure to respirable quartz occurred on all three farms with the highest individual concentration measured on the sandy soil farm (626 μg · m(-3)). Fifty-seven, 59, and 81% of the measurements on the sandy soil, sandy loam soil, and clay soil farm, respectively, exceeded the American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit value (TLV) of 25 μg · m(-3). Twelve and 13% of respirable quartz concentrations exceeded 100 μg · m(-3) on the sandy soil and sandy loam soil farms, respectively, but none exceeded this level on the clay soil farm. The proportions of measurements >100 μg · m(-3) were not significantly different between the sandy and sandy loam soil farms ('prop.test'; P = 0.65), but both were significantly larger than for the clay soil farm ('prop.test'; P = 0.0001). The percentage of quartz in respirable dust was determined for all three farms using measurements > the limit of detection. Percentages ranged from 0.5 to 94.4% with no significant difference in the median quartz percentages across the three farms (Kruskal-Wallis test; P = 0.91). This study demonstrates that there is significant potential for over-exposure to respirable quartz in

  1. Multilevel ensemble Kalman filter

    Chernov, Alexey; Hoel, Haakon; Law, Kody; Nobile, Fabio; Tempone, Raul

    2016-01-01

    This work embeds a multilevel Monte Carlo (MLMC) sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF). In terms of computational cost vs. approximation error the asymptotic performance of the multilevel ensemble Kalman filter (MLEnKF) is superior to the EnKF s.

  2. Side loading filter apparatus

    Reynolds, K.E.

    1981-01-01

    A side loading filter chamber for use with radioactive gases is described. The equipment incorporates an inexpensive, manually operated, mechanism for aligning filter units with a number of laterally spaced wall openings and for removing the units from the chamber. (U.K.)

  3. Multilevel ensemble Kalman filter

    Chernov, Alexey

    2016-01-06

    This work embeds a multilevel Monte Carlo (MLMC) sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF). In terms of computational cost vs. approximation error the asymptotic performance of the multilevel ensemble Kalman filter (MLEnKF) is superior to the EnKF s.

  4. Cold season soil respiration in response to grazing and warming in the High Arctic Svalbard

    Strebel, Ditte; Elberling, Bo; Morgner, Elke

    2010-01-01

    of Arctic Goose Habitat: Impacts of Land Use, Conservation and Elevated Temperatures). New measurements of soil CO2 effluxes, temperatures and water contents were regularly made from July to November 2007. SOC stocks were quantified, and the reactivity and composition measured by basal soil respiration (BSR...... be concluded that two years after a goose grazing experiment, SOC cycling was less than the natural variation within contrasting vegetation types....

  5. Permafrost collapse alters soil carbon stocks, respiration, CH4 , and N2O in upland tundra.

    Abbott, Benjamin W; Jones, Jeremy B

    2015-12-01

    Release of greenhouse gases from thawing permafrost is potentially the largest terrestrial feedback to climate change and one of the most likely to occur; however, estimates of its strength vary by a factor of thirty. Some of this uncertainty stems from abrupt thaw processes known as thermokarst (permafrost collapse due to ground ice melt), which alter controls on carbon and nitrogen cycling and expose organic matter from meters below the surface. Thermokarst may affect 20-50% of tundra uplands by the end of the century; however, little is known about the effect of different thermokarst morphologies on carbon and nitrogen release. We measured soil organic matter displacement, ecosystem respiration, and soil gas concentrations at 26 upland thermokarst features on the North Slope of Alaska. Features included the three most common upland thermokarst morphologies: active-layer detachment slides, thermo-erosion gullies, and retrogressive thaw slumps. We found that thermokarst morphology interacted with landscape parameters to determine both the initial displacement of organic matter and subsequent carbon and nitrogen cycling. The large proportion of ecosystem carbon exported off-site by slumps and slides resulted in decreased ecosystem respiration postfailure, while gullies removed a smaller portion of ecosystem carbon but strongly increased respiration and N2 O concentration. Elevated N2 O in gully soils persisted through most of the growing season, indicating sustained nitrification and denitrification in disturbed soils, representing a potential noncarbon permafrost climate feedback. While upland thermokarst formation did not substantially alter redox conditions within features, it redistributed organic matter into both oxic and anoxic environments. Across morphologies, residual organic matter cover, and predisturbance respiration explained 83% of the variation in respiration response. Consistent differences between upland thermokarst types may contribute to the

  6. A Global Database of Soil Respiration Data, Version 1.0

    National Aeronautics and Space Administration — ABSTRACT: This data set provides a soil respiration data database (SRDB), a near-universal compendium of published soil respiration (RS) data. Soil respiration, the...

  7. A Global Database of Soil Respiration Data, Version 2.0

    National Aeronautics and Space Administration — ABSTRACT: This data set provides an updated soil respiration database (SRDB), a near-universal compendium of published soil respiration (RS) data. Soil respiration,...

  8. Filtering and prediction

    Fristedt, B; Krylov, N

    2007-01-01

    Filtering and prediction is about observing moving objects when the observations are corrupted by random errors. The main focus is then on filtering out the errors and extracting from the observations the most precise information about the object, which itself may or may not be moving in a somewhat random fashion. Next comes the prediction step where, using information about the past behavior of the object, one tries to predict its future path. The first three chapters of the book deal with discrete probability spaces, random variables, conditioning, Markov chains, and filtering of discrete Markov chains. The next three chapters deal with the more sophisticated notions of conditioning in nondiscrete situations, filtering of continuous-space Markov chains, and of Wiener process. Filtering and prediction of stationary sequences is discussed in the last two chapters. The authors believe that they have succeeded in presenting necessary ideas in an elementary manner without sacrificing the rigor too much. Such rig...

  9. Filter cake breaker systems

    Garcia, Marcelo H.F. [Poland Quimica Ltda., Duque de Caxias, RJ (Brazil)

    2004-07-01

    Drilling fluids filter cakes are based on a combination of properly graded dispersed particles and polysaccharide polymers. High efficiency filter cakes are formed by these combination , and their formation on wellbore walls during the drilling process has, among other roles, the task of protecting the formation from instantaneous or accumulative invasion of drilling fluid filtrate, granting stability to well and production zones. Filter cake minimizes contact between drilling fluid filtrate and water, hydrocarbons and clay existent in formations. The uniform removal of the filter cake from the entire interval is a critical factor of the completion process. The main methods used to breaking filter cake are classified into two groups, external or internal, according to their removal mechanism. The aim of this work is the presentation of these mechanisms as well their efficiency. (author)

  10. Sub-micron filter

    Tepper, Frederick [Sanford, FL; Kaledin, Leonid [Port Orange, FL

    2009-10-13

    Aluminum hydroxide fibers approximately 2 nanometers in diameter and with surface areas ranging from 200 to 650 m.sup.2/g have been found to be highly electropositive. When dispersed in water they are able to attach to and retain electronegative particles. When combined into a composite filter with other fibers or particles they can filter bacteria and nano size particulates such as viruses and colloidal particles at high flux through the filter. Such filters can be used for purification and sterilization of water, biological, medical and pharmaceutical fluids, and as a collector/concentrator for detection and assay of microbes and viruses. The alumina fibers are also capable of filtering sub-micron inorganic and metallic particles to produce ultra pure water. The fibers are suitable as a substrate for growth of cells. Macromolecules such as proteins may be separated from each other based on their electronegative charges.

  11. Nonlinear image filtering within IDP++

    Lehman, S.K.; Wieting, M.G.; Brase, J.M.

    1995-02-09

    IDP++, image and data processing in C++, is a set of a signal processing libraries written in C++. It is a multi-dimension (up to four dimensions), multi-data type (implemented through templates) signal processing extension to C++. IDP++ takes advantage of the object-oriented compiler technology to provide ``information hiding.`` Users need only know C, not C++. Signals or data sets are treated like any other variable with a defined set of operators and functions. We here some examples of the nonlinear filter library within IDP++. Specifically, the results of MIN, MAX median, {alpha}-trimmed mean, and edge-trimmed mean filters as applied to a real aperture radar (RR) and synthetic aperture radar (SAR) data set.

  12. Monolithic Integrated Ceramic Waveguide Filters

    Hunter, IC; Sandhu, MY

    2014-01-01

    Design techniques for a new class of integrated monolithic high permittivity ceramic waveguide filters are presented. These filters enable a size reduction of 50% compared to air-filled TEM filters with the same unloaded Q-Factor. Designs for both chebyshev and asymmetric generalized chebyshev filter are presented, with experimental results for an 1800 MHz chebyshev filter showing excellent agreement with theory.

  13. Determination of permeability of ultra-fine cupric oxide aerosol through military filters and protective filters

    Kellnerová, E.; Večeřa, Z.; Kellner, J.; Zeman, T.; Navrátil, J.

    2018-03-01

    The paper evaluates the filtration and sorption efficiency of selected types of military combined filters and protective filters. The testing was carried out with the use of ultra-fine aerosol containing cupric oxide nanoparticles ranging in size from 7.6 nm to 299.6 nm. The measurements of nanoparticles were carried out using a scanning mobility particle sizer before and after the passage through the filter and a developed sampling device at the level of particle number concentration approximately 750000 particles·cm-3. The basic parameters of permeability of ultra-fine aerosol passing through the tested material were evaluated, in particular particle size, efficiency of nanoparticle capture by filter, permeability coefficient and overall filtration efficiency. Results indicate that the military filter and particle filters exhibited the highest aerosol permeability especially in the nanoparticle size range between 100–200 nm, while the MOF filters had the highest permeability in the range of 200 to 300 nm. The Filter Nuclear and the Health and Safety filter had 100% nanoparticle capture efficiency and were therefore the most effective. The obtained measurement results have shown that the filtration efficiency over the entire measured range of nanoparticles was sufficient; however, it was different for particular particle sizes.

  14. Growth of silicone-immobilized bacteria on polycarbonate membrane filters, a technique to study microcolony formation under anaerobic conditions.

    Højberg, O; Binnerup, S J; Sørensen, J

    1997-01-01

    A technique was developed to study microcolony formation by silicone-immobilized bacteria on polycarbonate membrane filters under anaerobic conditions. A sudden shift to anaerobiosis was obtained by submerging the filters in medium which was depleted for oxygen by a pure culture of bacteria. The technique was used to demonstrate that preinduction of nitrate reductase under low-oxygen conditions was necessary for nonfermenting, nitrate-respiring bacteria, e.g., Pseudomonas spp., to cope with a...

  15. Quantifying Components of Soil Respiration and Their Response to Abiotic Factors in Two Typical Subtropical Forest Stands, Southwest China

    Yu, Lei; Wang, Yujie; Wang, Yunqi; Sun, Suqi; Liu, Liziyuan

    2015-01-01

    Separating the components of soil respiration and understanding the roles of abiotic factors at a temporal scale among different forest types are critical issues in forest ecosystem carbon cycling. This study quantified the proportions of autotrophic (R A) and heterotrophic (R H) in total soil (R T) respiration using trenching and litter removal. Field studies were conducted in two typical subtropical forest stands (broadleaf and needle leaf mixed forest; bamboo forest) at Jinyun Mountain, near the Three Georges Reservoir in southwest China, during the growing season (Apr.–Sep.) from 2010 to 2012. The effects of air temperature (AT), soil temperature (ST) and soil moisture (SM) at 6cm depth, solar radiation (SR), pH on components of soil respiration were analyzed. Results show that: 1) SR, AT, and ST exhibited a similar temporal trend. The observed abiotic factors showed slight interannual variability for the two forest stands. 2) The contributions of R H and R A to R T for broadleaf and needle leaf mixed forest were 73.25% and 26.75%, respectively, while those for bamboo forest were 89.02% and 10.98%, respectively; soil respiration peaked from June to July. In both stands, CO2 released from the decomposition of soil organic matter (SOM), the strongest contributor to R T, accounted for over 63% of R H. 3) AT and ST were significantly positively correlated with R T and its components (psoil respiration. 4) Components of soil respiration were significantly different between two forest stands (psoil respiration and its components. PMID:25680112

  16. [Effects of management regime on soil respiration from agroecosystems].

    Chen, Shu-tao; Zhu, Da-wei; Niu, Chuan-po; Zou, Jian-wen; Wang, Chao; Sun, Wen-juan

    2009-10-15

    In order to examine the effects of management regime, such as nitrogen application and plowing method, on soil respiration from farmland, the static opaque chamber-gas chromatograph method was used to measure soil CO2 fluxes in situ. The field measurement was carried out for 5 growing seasons, which were the 2002-2003 wheat, 2003 maize and soybean, 2003-2004 wheat, 2004 maize and 2004-2005 wheat seasons. Our results showed that soil respiration increased in fertilizer-applied treatments compared with no fertilizer treatment after 3 times of fertilizer application on 9 November 2002, 14 February and 26 March 2003. And the most obvious increase appeared following the third fertilizer application. No significant difference in soil respiration was found among several fertilizer application treatments. The effect of plowing depth on soil respiration was contingent on preceding cropping practice. Over the 2003-2004 wheat-growing seasons (its preceding cropping practice was rice paddy), mean soil respiration rates were not significant different (p > 0.05) between no plowing treatment and shallow plowing treatment. The shallow plowing treatment CT2 led to higher soil CO2 losses compared with no plowing treatment of NT2 in the 2004 maize-growing season, however, the significant higher (p soil respiration rates occurred with no plowing treatment of NT3 in the following 2004-2005 wheat-growing season. Intensive plowing (25 cm depth), compared with no plowing practice (NT4), increased soil respiration significantly during the 2004-2005 wheat-growing season. Regression analysis showed that the exponential function could be employed to fit the relationship between soil respiration and temperature. The exponential relationship yielded the Q10 values which were varied from 1.26 to 3.60, with a mean value of 2.08. To evaluate the effect of temperature on soil respiration, the CO2 emission fluxes were normalized for each treatment and each crop growing season. Plotting the

  17. Ceramic fiber reinforced filter

    Stinton, David P.; McLaughlin, Jerry C.; Lowden, Richard A.

    1991-01-01

    A filter for removing particulate matter from high temperature flowing fluids, and in particular gases, that is reinforced with ceramic fibers. The filter has a ceramic base fiber material in the form of a fabric, felt, paper of the like, with the refractory fibers thereof coated with a thin layer of a protective and bonding refractory applied by chemical vapor deposition techniques. This coating causes each fiber to be physically joined to adjoining fibers so as to prevent movement of the fibers during use and to increase the strength and toughness of the composite filter. Further, the coating can be selected to minimize any reactions between the constituents of the fluids and the fibers. A description is given of the formation of a composite filter using a felt preform of commercial silicon carbide fibers together with the coating of these fibers with pure silicon carbide. Filter efficiency approaching 100% has been demonstrated with these filters. The fiber base material is alternately made from aluminosilicate fibers, zirconia fibers and alumina fibers. Coating with Al.sub.2 O.sub.3 is also described. Advanced configurations for the composite filter are suggested.

  18. Circuits and filters handbook

    Chen, Wai-Kai

    2003-01-01

    A bestseller in its first edition, The Circuits and Filters Handbook has been thoroughly updated to provide the most current, most comprehensive information available in both the classical and emerging fields of circuits and filters, both analog and digital. This edition contains 29 new chapters, with significant additions in the areas of computer-aided design, circuit simulation, VLSI circuits, design automation, and active and digital filters. It will undoubtedly take its place as the engineer's first choice in looking for solutions to problems encountered in the design, analysis, and behavi

  19. EMI filter design

    Ozenbaugh, Richard Lee

    2011-01-01

    With today's electrical and electronics systems requiring increased levels of performance and reliability, the design of robust EMI filters plays a critical role in EMC compliance. Using a mix of practical methods and theoretical analysis, EMI Filter Design, Third Edition presents both a hands-on and academic approach to the design of EMI filters and the selection of components values. The design approaches covered include matrix methods using table data and the use of Fourier analysis, Laplace transforms, and transfer function realization of LC structures. This edition has been fully revised

  20. Randomized Filtering Algorithms

    Katriel, Irit; Van Hentenryck, Pascal

    2008-01-01

    of AllDifferent and is generalization, the Global Cardinality Constraint. The first delayed filtering scheme is a Monte Carlo algorithm: its running time is superior, in the worst case, to that of enforcing are consistency after every domain event, while its filtering effectiveness is analyzed...... in the expected sense. The second scheme is a Las Vegas algorithm using filtering triggers: Its effectiveness is the same as enforcing are consistency after every domain event, while in the expected case it is faster by a factor of m/n, where n and m are, respectively, the number of nodes and edges...

  1. Soil Respiration in Semiarid Temperate Grasslands under Various Land Management.

    Zhen Wang

    Full Text Available Soil respiration, a major component of the global carbon cycle, is significantly influenced by land management practices. Grasslands are potentially a major sink for carbon, but can also be a source. Here, we investigated the potential effect of land management (grazing, clipping, and ungrazed enclosures on soil respiration in the semiarid grassland of northern China. Our results showed the mean soil respiration was significantly higher under enclosures (2.17 μmol.m(-2.s(-1 and clipping (2.06 μmol.m(-2.s(-1 than under grazing (1.65 μmol.m-(2.s(-1 over the three growing seasons. The high rates of soil respiration under enclosure and clipping were associated with the higher belowground net primary productivity (BNPP. Our analyses indicated that soil respiration was primarily related to BNPP under grazing, to soil water content under clipping. Using structural equation models, we found that soil water content, aboveground net primary productivity (ANPP and BNPP regulated soil respiration, with soil water content as the predominant factor. Our findings highlight that management-induced changes in abiotic (soil temperature and soil water content and biotic (ANPP and BNPP factors regulate soil respiration in the semiarid temperate grassland of northern China.

  2. Soil Respiration in Semiarid Temperate Grasslands under Various Land Management.

    Wang, Zhen; Ji, Lei; Hou, Xiangyang; Schellenberg, Michael P

    2016-01-01

    Soil respiration, a major component of the global carbon cycle, is significantly influenced by land management practices. Grasslands are potentially a major sink for carbon, but can also be a source. Here, we investigated the potential effect of land management (grazing, clipping, and ungrazed enclosures) on soil respiration in the semiarid grassland of northern China. Our results showed the mean soil respiration was significantly higher under enclosures (2.17 μmol.m(-2).s(-1)) and clipping (2.06 μmol.m(-2).s(-1)) than under grazing (1.65 μmol.m-(2).s(-1)) over the three growing seasons. The high rates of soil respiration under enclosure and clipping were associated with the higher belowground net primary productivity (BNPP). Our analyses indicated that soil respiration was primarily related to BNPP under grazing, to soil water content under clipping. Using structural equation models, we found that soil water content, aboveground net primary productivity (ANPP) and BNPP regulated soil respiration, with soil water content as the predominant factor. Our findings highlight that management-induced changes in abiotic (soil temperature and soil water content) and biotic (ANPP and BNPP) factors regulate soil respiration in the semiarid temperate grassland of northern China.

  3. SEASONAL CHANGES IN ROOT AND SOIL RESPIRATION OF OZONE-EXPOSED PONDEROSA PINE (PINUS PONDEROSA) GROWN IN DIFFERENT SUBSTRATES

    Exposure to(ozone 0-3)has been shown to decrease the allocation of carbon to tree roots. Decreased allocation of carbon to roots might disrupt root metabolism and rhizosphere organisms. The effects of soil type and shoot 0, exposure on below-ground respiration and soil microbial ...

  4. Respiration responses of a polA1 and a tif-1 mutant of Escherichia coli to far-ultraviolet irradiation

    Swenson, P.A.

    1981-01-01

    Cessation of respiration in Escherichia coli 60 min after far - ultra-violet (254 nm) irradiation is dependent upon the recA and lexA gene products and is regulated by cyclic 3', 5'-adenosine monophosphate (cAMP) and its receptor protein. Two E. coli B/r mutants were studied, polA1 and tif-1, both of which express other rec/lex functions after UV irradiation. After receiving a relatively high UV fluence, the polA1 mutant, deficient in DNA polymerase 1, showed a respiration shutoff response like the wild type cells. 5-Fluorouracil and rifampin, an RNA synthesis inhibitor, did not prevent respiration shutoff in the mutant cells as they did in the wild type cells. At lower fluences which did not shut off respiration of polA1 cells, cAMP did not cause a more complete shutoff as it did for the wild type cells. The tif-1 mutant has a modified recA protein, and when unirradiated cells are incubated at 42 0 C they form filaments, mutate, and show other rec/lex responses. This mutant did not shut off its respiration at either 30 or 42 0 C, and the response was not modified by cAMP. In an E. coli K12 strain, W3110, 52 J/m 2 UV did not shut off respiration and cAMP had no effect. (author)

  5. Quantifying the predictability of diaphragm motion during respiration with a noninvasive external marker

    Vedam, S.S.; Kini, V.R.; Keall, P.J.; Ramakrishnan, V.; Mostafavi, H.; Mohan, R.

    2003-01-01

    The aim of this work was to quantify the ability to predict intrafraction diaphragm motion from an external respiration signal during a course of radiotherapy. The data obtained included diaphragm motion traces from 63 fluoroscopic lung procedures for 5 patients, acquired simultaneously with respiratory motion signals (an infrared camera-based system was used to track abdominal wall motion). During these sessions, the patients were asked to breathe either (i) without instruction, (ii) with audio prompting, or (iii) using visual feedback. A statistical general linear model was formulated to describe the relationship between the respiration signal and diaphragm motion over all sessions and for all breathing training types. The model parameters derived from the first session for each patient were then used to predict the diaphragm motion for subsequent sessions based on the respiration signal. Quantification of the difference between the predicted and actual motion during each session determined our ability to predict diaphragm motion during a course of radiotherapy. This measure of diaphragm motion was also used to estimate clinical target volume (CTV) to planning target volume (PTV) margins for conventional, gated, and proposed four-dimensional (4D) radiotherapy. Results from statistical analysis indicated a strong linear relationship between the respiration signal and diaphragm motion (p<0.001) over all sessions, irrespective of session number (p=0.98) and breathing training type (p=0.19). Using model parameters obtained from the first session, diaphragm motion was predicted in subsequent sessions to within 0.1 cm (1 σ) for gated and 4D radiotherapy. Assuming a 0.4 cm setup error, superior-inferior CTV-PTV margins of 1.1 cm for conventional radiotherapy could be reduced to 0.8 cm for gated and 4D radiotherapy. The diaphragm motion is strongly correlated with the respiration signal obtained from the abdominal wall. This correlation can be used to predict diaphragm

  6. Differential response of microbial respiration to supplied nitrogen forms in 3 contrasting alpine meadow soils on the Tibetan Plateau

    Xiaoyang Zeng

    Full Text Available ABSTRACT An incubation experiment was conducted to examine the effects of nitrogen (N applications in different forms (NH4NO3, NH4Cl, and KNO3 on microbial respiration considering 3 different alpine meadow soils (C poor soil, pH = 8.1, 1.6% C; C moderate soil, pH = 6.0, 5.0% C; C rich soil, pH = 7.1, 7.4% C in the Tibetan Plateau. The addition of NH4NO3 and NH4Cl increased the microbial respiration in C poor soil, but KNO3 had no effect. The inorganic N forms had no effects on C rich soil, but decreased microbial respiration in C moderate soil. Soil microbial respiration levels across the different types were ordered as follows: C poor soil < C rich soil < C moderate soil, regardless of N addition. These results suggest that the effect of N on microbial respiration in alpine meadow soils is more dependent on the initial soil pH than on soil C availability.

  7. The Low Energy-Coupling Respiration in Zymomonas mobilis Accelerates Flux in the Entner-Doudoroff Pathway.

    Reinis Rutkis

    Full Text Available Performing oxidative phosphorylation is the primary role of respiratory chain both in bacteria and eukaryotes. Yet, the branched respiratory chains of prokaryotes contain alternative, low energy-coupling electron pathways, which serve for functions other than oxidative ATP generation (like those of respiratory protection, adaptation to low-oxygen media, redox balancing, etc., some of which are still poorly understood. We here demonstrate that withdrawal of reducing equivalents by the energetically uncoupled respiratory chain of the bacterium Zymomonas mobilis accelerates its fermentative catabolism, increasing the glucose consumption rate. This is in contrast to what has been observed in other respiring bacteria and yeast. This effect takes place after air is introduced to glucose-consuming anaerobic cell suspension, and can be simulated using a kinetic model of the Entner-Doudoroff pathway in combination with a simple net reaction of NADH oxidation that does not involve oxidative phosphorylation. Although aeration hampers batch growth of respiring Z. mobilis culture due to accumulation of toxic byproducts, nevertheless under non-growing conditions respiration is shown to confer an adaptive advantage for the wild type over the non-respiring Ndh knock-out mutant. If cells get occasional access to limited amount of glucose for short periods of time, the elevated glucose uptake rate selectively improves survival of the respiring Z. mobilis phenotype.

  8. Changes in mitochondrial respiration in the human placenta over gestation.

    Holland, Olivia J; Hickey, Anthony J R; Alvsaker, Anna; Moran, Stephanie; Hedges, Christopher; Chamley, Lawrence W; Perkins, Anthony V

    2017-09-01

    Placental mitochondria are subjected to micro-environmental changes throughout gestation, in particular large variations in oxygen. How placental mitochondrial respiration adapts to changing oxygen concentrations remains unexplored. Additionally, placental tissue is often studied in culture; however, the effect of culture on placental mitochondria is unclear. Placental tissue was obtained from first trimester and term (laboured and non-laboured) pregnancies, and selectively permeabilized to access mitochondria. Respirometry was used to compare respiration states and substrate use in mitochondria. Additionally, explants of placental tissue were cultured for four, 12, 24, 48, or 96 h and respiration measured. Mitochondrial respiration decreased at 11 weeks compared to earlier gestations (p = 0.05-0.001), and mitochondrial content increased at 12-13 weeks compared to 7-10 weeks (p = 0.042). In term placentae, oxidative phosphorylation (OXPHOS) through mitochondrial complex IV (p Respiration was increased (p ≤ 0.006-0.001) in laboured compared to non-laboured placenta. After four hours of culture, respiration was depressed compared to fresh tissue from the same placenta and continued to decline with time in culture. Markers of apoptosis were increased, while markers of autophagy, mitochondrial biogenesis, and mitochondrial membrane potential were decreased after four hours of culture. Respiration and mitochondrial content alter over gestation/with labour. Decreased respiration at 11 weeks and increased mitochondrial content at 12-13 weeks may relate to onset of maternal blood flow, and increased respiration as a result of labour may be an adaptation to ischaemia-reperfusion. At term, mitochondria were more susceptible to changes in respiratory function relative to first trimester when cultured in vitro, perhaps reflecting changes in metabolic demands as gestation progresses. Metabolic plasticity of placental mitochondria has relevance to placenta

  9. Availability, consistency and evidence-base of policies and guidelines on the use of mask and respirator to protect hospital health care workers: a global analysis.

    Chughtai, Abrar Ahmad; Seale, Holly; MacIntyre, Chandini Raina

    2013-05-31

    Currently there is an ongoing debate and limited evidence on the use of masks and respirators for the prevention of respiratory infections in health care workers (HCWs). This study aimed to examine available policies and guidelines around the use of masks and respirators in HCWs and to describe areas of consistency between guidelines, as well as gaps in the recommendations, with reference to the WHO and the CDC guidelines. Policies and guidelines related to mask and respirator use for the prevention of influenza, SARS and TB were examined. Guidelines from the World Health Organization (WHO), the Center for Disease Control and Prevention (CDC), three high-income countries and six low/middle-income countries were selected. Uniform recommendations are made by the WHO and the CDC in regards to protecting HCWs against seasonal influenza (a mask for low risk situations and a respirator for high risk situations) and TB (use of a respirator). However, for pandemic influenza and SARS, the WHO recommends mask use in low risk and respirators in high risk situations, whereas, the CDC recommends respirators in both low and high risk situations. Amongst the nine countries reviewed, there are variations in the recommendations for all three diseases. While, some countries align with the WHO recommendations, others align with those made by the CDC. The choice of respirator and the level of filtering ability vary amongst the guidelines and the different diseases. Lastly, none of the policies discuss reuse, extended use or the use of cloth masks. Currently, there are significant variations in the policies and recommendations around mask and respirator use for protection against influenza, SARS and TB. These differences may reflect the scarcity of level-one evidence available to inform policy development. The lack of any guidelines on the use of cloth masks, despite widespread use in many low and middle-income countries, remains a policy gap. Health organizations and countries should

  10. Load compensation for single phase system using series active filter ...

    Load compensation for single phase system using series active filter. ... KK Mishra, R Gupta ... load varies from time to time, the non linear load ranging from voltage source type harmonic load (VSHL) dominant to current source type harmonic ...

  11. Electro-optical tunable birefringent filter

    Levinton, Fred M [Princeton, NJ

    2012-01-31

    An electrically tunable Lyot type filter is a Lyot that include one or more filter elements. Each filter element may have a planar, solid crystal comprised of a material that exhibits birefringence and is electro-optically active. Transparent electrodes may be coated on each face of the crystal. An input linear light polarizer may be located on one side of the crystal and oriented at 45 degrees to the optical axis of the birefringent crystal. An output linear light polarizer may be located on the other side of the crystal and oriented at -45 degrees with respect to the optical axis of the birefringent crystal. When an electric voltage is applied between the electrodes, the retardation of the crystal changes and so does the spectral transmission of the optical filter.

  12. Iodine filters in nuclear power stations

    Wilhelm, J.G.

    1977-04-01

    On the basis of calculated and recorded release rates of nuclear power plants, the significance of iodine releases in the invironmental impact relative to other nuclides is discussed. The release pathways for iodine in LWR-type reactors and the efficiency of various methods to lower the activity release are given. The airborne species of iodine are discussed with regard to their removal in iodine sorption filters and environmental impact. The technical status of iodine removal by means of iodine sorption filters is studied for normal operation and accident conditions in nuclear power stations on the basis of the data given in the relevant literature for the efficiency of a number of iodine sorption materials. The applicability of concepts for ventilation and containment and their influence on iodine filter systems are discussed. Design, structure, and testing of iodine sorption filters are treated in detail; recommendations for design are given, and failure sources are mentioned. (orig.) [de

  13. Oxygen and carbon isotopic compositions of gases respired by humans

    Epstein, S.; Zeiri, L.

    1988-01-01

    Oxygen-isotope fractionation associated with respiration in human individuals at rest is linearly related to the fraction of the O 2 utilized in the respiration process. The slope of this relationship is affected by a history of smoking, by vigorous exercise, and by the N 2 /O 2 ratio of the inhaled gas. For patients who suffer anemia-related diseases, the slope of this relationship is directly proportional to their level of hemoglobin. These results introduce a new approach for studying the mechanisms of O 2 consumption in human respiration and how they are affected by related diseases

  14. Controls on Ecosystem and Root Respiration in an Alaskan Peatland

    McConnell, N. A.; McGuire, A. D.; Harden, J. W.; Kane, E. S.; Turetsky, M. R.

    2010-12-01

    Boreal ecosystems cover 14% of the vegetated surface on earth and account for 25-30% of the world’s soil carbon (C), mainly due to large carbon stocks in deep peat and frozen soil layers. While peatlands have served as historical sinks of carbon, global climate change may trigger re-release of C to the atmosphere and may turn these ecosystems into net C sources. Rates of C release from a peatland are determined by regional climate and local biotic and abiotic factors such as vegetation cover, thaw depth, and peat thickness. Soil CO2 fluxes are driven by both autotrophic (plant) respiration and heterotrophic (microbial) respiration. Thus, changes in plant and microbial activity in the soil will impact CO2 emissions from peatlands. In this study, we explored environmental and vegetation controls on ecosystem respiration and root respiration in a variety of wetland sites. The study was conducted at the Alaskan Peatland Experiment (APEX; www.uoguelph.ca/APEX) sites in the Bonanza Creek Experimental Forest located 35 km southwest of Fairbanks Alaska. We measured ecosystem respiration, root respiration, and monitored a suite of environmental variables along a vegetation and soil moisture gradient including a black spruce stand with permafrost, a shrubby site with permafrost, a tussock grass site, and a herbaceous open rich fen. Within the rich fen, we have been conducting water table manipulations including a control, lowered, and raised water table treatment. In each of our sites, we measured total ecosystem respiration using static chambers and root respiration by harvesting roots from the uppermost 20 cm and placing them in a root cuvette to obtain a root flux. Ecosystem respiration (ER) on a μmol/m2/sec basis varied across sites. Water table was a significant predictor of ER at the lowered manipulation site and temperature was a strong predictor at the control site in the rich fen. Water table and temperature were both significant predictors of ER at the raised

  15. Herd protection effect of N95 respirators in healthcare workers.

    Chen, Xin; Chughtai, Abrar Ahmad; MacIntyre, Chandini Raina

    2017-12-01

    Objective To determine if there was herd protection conferred to unprotected healthcare workers (HCWs) by N95 respirators worn by colleagues. Methods Data were analysed from a prospective cluster randomized clinical trial conducted in Beijing, China between 1 December 2008 and 15 January 2009. A minimum compliance level (MCL) of N95 respirators for prevention of clinical respiratory illness (CRI) was set based on various compliance cut-offs. The CRI rates were compared between compliant (≥MCL) and non-compliant (protection from use of N95 respirators by colleagues within a hospital ward.

  16. Estimating daytime ecosystem respiration from eddy-flux data

    Bruhn, Dan; Mikkelsen, Teis Nørgaard; Herbst, Mathias

    2011-01-01

    To understand what governs the patterns of net ecosystem exchange of CO2, an understanding of factors influencing the component fluxes, ecosystem respiration and gross primary production is needed. In the present paper, we introduce an alternative method for estimating daytime ecosystem respiration...... based on whole ecosystem fluxes from a linear regression of photosynthetic photon flux density data vs. daytime net ecosystem exchange data at forest ecosystem level. This method is based on the principles of the Kok-method applied at leaf level for estimating daytime respiration. We demonstrate...

  17. Fractal-Based Analysis of the Influence of Music on Human Respiration

    Reza Namazi, H.

    An important challenge in respiration related studies is to investigate the influence of external stimuli on human respiration. Auditory stimulus is an important type of stimuli that influences human respiration. However, no one discovered any trend, which relates the characteristics of the auditory stimuli to the characteristics of the respiratory signal. In this paper, we investigate the correlation between auditory stimuli and respiratory signal from fractal point of view. We found out that the fractal structure of respiratory signal is correlated with the fractal structure of the applied music. Based on the obtained results, the music with greater fractal dimension will result in respiratory signal with smaller fractal dimension. In order to verify this result, we benefit from approximate entropy. The results show the respiratory signal will have smaller approximate entropy by choosing the music with smaller approximate entropy. The method of analysis could be further investigated to analyze the variations of different physiological time series due to the various types of stimuli when the complexity is the main concern.

  18. Metalcasting: Filtering Molten Metal

    Lauren Poole; Lee Recca

    1999-01-01

    A more efficient method has been created to filter cast molten metal for impurities. Read about the resulting energy and money savings that can accrue to many different industries from the use of this exciting new technology

  19. Perspectives on Nonlinear Filtering

    Law, Kody

    2015-01-01

    The solution to the problem of nonlinear filtering may be given either as an estimate of the signal (and ideally some measure of concentration), or as a full posterior distribution. Similarly, one may evaluate the fidelity of the filter either by its ability to track the signal or its proximity to the posterior filtering distribution. Hence, the field enjoys a lively symbiosis between probability and control theory, and there are plenty of applications which benefit from algorithmic advances, from signal processing, to econometrics, to large-scale ocean, atmosphere, and climate modeling. This talk will survey some recent theoretical results involving accurate signal tracking with noise-free (degenerate) dynamics in high-dimensions (infinite, in principle, but say d between 103 and 108 , depending on the size of your application and your computer), and high-fidelity approximations of the filtering distribution in low dimensions (say d between 1 and several 10s).

  20. HEPA air filter (image)

    ... pet dander and other irritating allergens from the air. Along with other methods to reduce allergens, such ... controlling the amount of allergens circulating in the air. HEPA filters can be found in most air ...

  1. Updating the OMERACT filter

    Tugwell, Peter; Boers, Maarten; D'Agostino, Maria-Antonietta

    2014-01-01

    OBJECTIVE: The Outcome Measures in Rheumatology (OMERACT) Filter provides guidelines for the development and validation of outcome measures for use in clinical research. The "Truth" section of the OMERACT Filter requires that criteria be met to demonstrate that the outcome instrument meets...... the criteria for content, face, and construct validity. METHODS: Discussion groups critically reviewed a variety of ways in which case studies of current OMERACT Working Groups complied with the Truth component of the Filter and what issues remained to be resolved. RESULTS: The case studies showed...... that there is broad agreement on criteria for meeting the Truth criteria through demonstration of content, face, and construct validity; however, several issues were identified that the Filter Working Group will need to address. CONCLUSION: These issues will require resolution to reach consensus on how Truth...

  2. Updating the OMERACT filter

    Kirwan, John R; Boers, Maarten; Hewlett, Sarah

    2014-01-01

    OBJECTIVE: The Outcome Measures in Rheumatology (OMERACT) Filter provides guidelines for the development and validation of outcome measures for use in clinical research. The "Truth" section of the OMERACT Filter presupposes an explicit framework for identifying the relevant core outcomes...... for defining core areas of measurement ("Filter 2.0 Core Areas of Measurement") was presented at OMERACT 11 to explore areas of consensus and to consider whether already endorsed core outcome sets fit into this newly proposed framework. METHODS: Discussion groups critically reviewed the extent to which case......, presentation, and clarity of the framework were questioned. The discussion groups and subsequent feedback highlighted 20 such issues. CONCLUSION: These issues will require resolution to reach consensus on accepting the proposed Filter 2.0 framework of Core Areas as the basis for the selection of Core Outcome...

  3. Paul Rodgersi filter Kohilas

    2000-01-01

    28. I Kohila keskkoolis kohaspetsiifiline skulptuur ja performance "Filter". Kooli 130. aastapäeva tähistava ettevõtmise eesotsas oli skulptor Paul Rodgers ja kaks viimase klassi noormeest ئ Marko Heinmäe, Hendrik Karm.

  4. Perspectives on Nonlinear Filtering

    Law, Kody

    2015-01-07

    The solution to the problem of nonlinear filtering may be given either as an estimate of the signal (and ideally some measure of concentration), or as a full posterior distribution. Similarly, one may evaluate the fidelity of the filter either by its ability to track the signal or its proximity to the posterior filtering distribution. Hence, the field enjoys a lively symbiosis between probability and control theory, and there are plenty of applications which benefit from algorithmic advances, from signal processing, to econometrics, to large-scale ocean, atmosphere, and climate modeling. This talk will survey some recent theoretical results involving accurate signal tracking with noise-free (degenerate) dynamics in high-dimensions (infinite, in principle, but say d between 103 and 108 , depending on the size of your application and your computer), and high-fidelity approximations of the filtering distribution in low dimensions (say d between 1 and several 10s).

  5. Structural testing of salt loaded HEPA filters for WIPP

    Smith, P.R.; Leslie, I.H.; Hensel, E.C.; Shultheis, T.M.; Walls, J.R.

    1993-01-01

    The ventilation studies of the Waste Isolation Pilot Plant described in this paper were performed by personnel from New Mexico State Univ. in collaboration with Sandia National Laboratories, Los Alamos National Laboratory and Westinghouse Corporation. High efficiency particulate air filters (0.61m by 0.61m by 0.3m) of the type in use at the Waste Isolation Pilot Plant were loaded with salt aerosol provided from that site. The structural strength of salt-loaded, high-efficiency filters was investigated at two humidity levels, high (75%RH) and low (13-14% RH), by subjecting the filters to pressure transients of the types expected from tornadoes. Filters loaded under the high humidity condition proved to have a greater structural strength than did the filters loaded under the low humidity conditions, when both types were subjected to tornado-like pressure pulses. This unexpected results was apparently due to the crystallization of salt upon the wire face guard of the HEPA filter loaded under the high humidity condition which kept salt from penetrating the filter medium while still providing a substantial pressure drop at the standard flow rate. Results are also presented for HEPA filters pre-conditioned at 100% RH before structural testing and for HEPA filters in series with pre-filters

  6. Study of factors that influence the use of respirators in uranium mines

    Kalos, F.

    1986-06-01

    A statistical analysis was performed of the responses to a user's survey by uranium miners who were voluntary users of a helmet-type powered respirator. The analysis concludes that the duration of visor-lifting was lognormally distributed with a geometric mean of 1.15 hours. Use depends strongly on job category. Many of the factors examined by the survey were use-dependent instead of use-dtermining, or had no effect on proper use. Many of the miners stated the respirator could not cope with hard work, its visor fogged up. The very abundance of these comments prevented confirming an association between fogging and use by statistical means. Recommendations on future user's surveys are given

  7. Air filters for use at nuclear facilities

    Linder, P [Aktiebolaget Atomenergi, Studsvik, Nykoeping (Sweden)

    1970-12-01

    The ventilation system of a nuclear facility plays a vital role in ensuring that the air in working areas and the environment remains free from radioactive contamination. An earlier IAEA publication, Techniques for Controlling Air Pollution from the Operation of Nuclear Facilities, Safety Series No. 17, deals with the design and operation of ventilation systems at nuclear facilities. These systems are usually provided with air-cleaning devices which remove the contaminants from the air. This publication is intended as a guide to those who are concerned with the design of air-filtering systems and with the testing, operation and maintenance of air-filter installations at nuclear facilities. Emphasis is mainly placed on so-called high-efficiency particulate air filters (HEPA filters) and on providing general information on them. Besides describing the usual filter types, their dimensions and construction materials, the guidebook attempts to explain their properties and behaviour under different operating conditions. It also gives advice on testing and handling the filters so that effective and safe performance is ensured. The guidebook should serve as an introduction to the use of high efficiency particulate air filters in countries where work with radioactive materials has only recently commenced. The list of references at the end of the book indicates sources of more advanced information for those who already have comprehensive experience in this field. It is assumed here that the filters are obtained from a manufacturer, and the guidebook thus contains no information on the design and development of the filter itself, nor does it deal with the cleaning of the intake air to a plant, with gas sorption or protective respiratory equipment.

  8. Air filters for use at nuclear facilities

    Linder, P.

    1970-01-01

    The ventilation system of a nuclear facility plays a vital role in ensuring that the air in working areas and the environment remains free from radioactive contamination. An earlier IAEA publication, Techniques for Controlling Air Pollution from the Operation of Nuclear Facilities, Safety Series No. 17, deals with the design and operation of ventilation systems at nuclear facilities. These systems are usually provided with air-cleaning devices which remove the contaminants from the air. This publication is intended as a guide to those who are concerned with the design of air-filtering systems and with the testing, operation and maintenance of air-filter installations at nuclear facilities. Emphasis is mainly placed on so-called high-efficiency particulate air filters (HEPA filters) and on providing general information on them. Besides describing the usual filter types, their dimensions and construction materials, the guidebook attempts to explain their properties and behaviour under different operating conditions. It also gives advice on testing and handling the filters so that effective and safe performance is ensured. The guidebook should serve as an introduction to the use of high efficiency particulate air filters in countries where work with radioactive materials has only recently commenced. The list of references at the end of the book indicates sources of more advanced information for those who already have comprehensive experience in this field. It is assumed here that the filters are obtained from a manufacturer, and the guidebook thus contains no information on the design and development of the filter itself, nor does it deal with the cleaning of the intake air to a plant, with gas sorption or protective respiratory equipment

  9. Spatial filter issues

    Murray, J.E.; Estabrook, K.G.; Milam, D.; Sell, W.D.; Van Wonterghem, R.M.; Feil, M.D.; Rubenchick, A.M.

    1996-01-01

    Experiments and calculations indicate that the threshold pressure in spatial filters for distortion of a transmitted pulse scales approximately as I O.2 and (F number-sign) 2 over the intensity range from 10 14 to 2xlO 15 W/CM 2 . We also demonstrated an interferometric diagnostic that will be used to measure the scaling relationships governing pinhole closure in spatial filters

  10. Microwave Resonators and Filters

    2015-12-22

    1 Microwave Resonators and Filters Daniel E. Oates MIT Lincoln Laboratory 244 Wood St. Lexington, MA 02478 USA Email: oates@ll.mit.edu...explained in other chapters, the surface resistance of superconductors at microwave frequencies can be as much as three orders of magnitude lower than the...resonators and filters in the first edition of this handbook (Z.-Y. Shen 2003) discussed the then state of the art of microwave frequency applications

  11. Staging with spatial filters

    Glaze, J.

    1974-01-01

    It is known that small scale beam instabilities limit the focusable energy that can be achieved from a terawatt laser chain. Spatial filters are currently being used on CYCLOPS to ameliorate this problem. Realizing the full advantage of such a filter, however, may require certain staging modifications. A staging methodology is discussed that should be applicable to the CYCLOPS, 381, and SHIVA systems. Experiments are in progress on CYCLOPS that will address directly the utility of the proposed approach

  12. Occupational Exposure to Respirable Dust, Respirable Crystalline Silica and Diesel Engine Exhaust Emissions in the London Tunnelling Environment.

    Galea, Karen S; Mair, Craig; Alexander, Carla; de Vocht, Frank; van Tongeren, Martie

    2016-03-01

    Personal 8-h shift exposure to respirable dust, diesel engine exhaust emissions (DEEE) (as respirable elemental carbon), and respirable crystalline silica of workers involved in constructing an underground metro railway tunnel was assessed. Black carbon (BC) concentrations were also assessed using a MicroAeth AE51. During sprayed concrete lining (SCL) activities in the tunnel, the geometric mean (GM) respirable dust exposure level was 0.91mg m(-3), with the highest exposure measured on a back-up sprayer (3.20mg m(-3)). The GM respirable crystalline silica concentration for SCL workers was 0.03mg m(-3), with the highest measurement also for the back-up sprayer (0.24mg m(-3)). During tunnel boring machine (TBM) activities, the GM respirable dust concentration was 0.54mg m(-3). The GM respirable elemental carbon concentration for all the TBM operators was 18 µg m(-3); with the highest concentration measured on a segment lifter. The BC concentrations were higher in the SCL environment in comparison to the TBM environment (daily GM 18-54 µg m(-3) versus 3-6 µg m(-3)). This small-scale monitoring campaign provides additional personal data on exposures experienced by underground tunnel construction workers. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  13. Depth Filters Containing Diatomite Achieve More Efficient Particle Retention than Filters Solely Containing Cellulose Fibers.

    Buyel, Johannes F; Gruchow, Hannah M; Fischer, Rainer

    2015-01-01

    The clarification of biological feed stocks during the production of biopharmaceutical proteins is challenging when large quantities of particles must be removed, e.g., when processing crude plant extracts. Single-use depth filters are often preferred for clarification because they are simple to integrate and have a good safety profile. However, the combination of filter layers must be optimized in terms of nominal retention ratings to account for the unique particle size distribution in each feed stock. We have recently shown that predictive models can facilitate filter screening and the selection of appropriate filter layers. Here we expand our previous study by testing several filters with different retention ratings. The filters typically contain diatomite to facilitate the removal of fine particles. However, diatomite can interfere with the recovery of large biopharmaceutical molecules such as virus-like particles and aggregated proteins. Therefore, we also tested filtration devices composed solely of cellulose fibers and cohesive resin. The capacities of both filter types varied from 10 to 50 L m(-2) when challenged with tobacco leaf extracts, but the filtrate turbidity was ~500-fold lower (~3.5 NTU) when diatomite filters were used. We also tested pre-coat filtration with dispersed diatomite, which achieved capacities of up to 120 L m(-2) with turbidities of ~100 NTU using bulk plant extracts, and in contrast to the other depth filters did not require an upstream bag filter. Single pre-coat filtration devices can thus replace combinations of bag and depth filters to simplify the processing of plant extracts, potentially saving on time, labor and consumables. The protein concentrations of TSP, DsRed and antibody 2G12 were not affected by pre-coat filtration, indicating its general applicability during the manufacture of plant-derived biopharmaceutical proteins.

  14. Depth filters containing diatomite achieve more efficient particle retention than filters solely containing cellulose fibers

    Johannes Felix Buyel

    2015-12-01

    Full Text Available The clarification of biological feed stocks during the production of biopharmaceutical proteins is challenging when large quantities of particles must be removed, e.g. when processing crude plant extracts. Single-use depth filters are often preferred for clarification because they are simple to integrate and have a good safety profile. However, the combination of filter layers must be optimized in terms of nominal retention ratings to account for the unique particle size distribution in each feed stock. We have recently shown that predictive models can facilitate filter screening and the selection of appropriate filter layers. Here we expand our previous study by testing several filters with different retention ratings. The filters typically contain diatomite to facilitate the removal of fine particles. However, diatomite can interfere with the recovery of large biopharmaceutical molecules such as virus-like particles and aggregated proteins. Therefore, we also tested filtration devices composed solely of cellulose fibers and cohesive resin. The capacities of both filter types varied from 10 to 50 L m-2 when challenged with tobacco leaf extracts, but the filtrate turbidity was ~500-fold lower (~3.5 NTU when diatomite filters were used. We also tested pre coat filtration with dispersed diatomite, which achieved capacities of up to 120 L m-2 with turbidities of ~100 NTU using bulk plant extracts, and in contrast to the other depth filters did not require an upstream bag filter. Single pre-coat filtration devices can thus replace combinations of bag and depth filters to simplify the processing of plant extracts, potentially saving on time, labor and consumables. The protein concentrations of TSP, DsRed and antibody 2G12 were not affected by pre-coat filtration, indicating its general applicability during the manufacture of plant-derived biopharmaceutical proteins.

  15. Inorganic UV filters

    Eloísa Berbel Manaia

    2013-06-01

    Full Text Available Nowadays, concern over skin cancer has been growing more and more, especially in tropical countries where the incidence of UVA/B radiation is higher. The correct use of sunscreen is the most efficient way to prevent the development of this disease. The ingredients of sunscreen can be organic and/or inorganic sun filters. Inorganic filters present some advantages over organic filters, such as photostability, non-irritability and broad spectrum protection. Nevertheless, inorganic filters have a whitening effect in sunscreen formulations owing to the high refractive index, decreasing their esthetic appeal. Many techniques have been developed to overcome this problem and among them, the use of nanotechnology stands out. The estimated amount of nanomaterial in use must increase from 2000 tons in 2004 to a projected 58000 tons in 2020. In this context, this article aims to analyze critically both the different features of the production of inorganic filters (synthesis routes proposed in recent years and the permeability, the safety and other characteristics of the new generation of inorganic filters.

  16. Non-contact respiration monitoring for in-vivo murine micro computed tomography: characterization and imaging applications

    Burk, Laurel M; Lee, Yueh Z; Wait, J Matthew; Lu Jianping; Zhou, Otto Z

    2012-01-01

    A cone beam micro-CT has previously been utilized along with a pressure-tracking respiration sensor to acquire prospectively gated images of both wild-type mice and various adult murine disease models. While the pressure applied to the abdomen of the subject by this sensor is small and is generally without physiological effect, certain disease models of interest, as well as very young animals, are prone to atelectasis with added pressure, or they generate too weak a respiration signal with this method to achieve optimal prospective gating. In this work we present a new fibre-optic displacement sensor which monitors respiratory motion of a subject without requiring physical contact. The sensor outputs an analogue signal which can be used for prospective respiration gating in micro-CT imaging. The device was characterized and compared against a pneumatic air chamber pressure sensor for the imaging of adult wild-type mice. The resulting images were found to be of similar quality with respect to physiological motion blur; the quality of the respiration signal trace obtained using the non-contact sensor was comparable to that of the pressure sensor and was superior for gating purposes due to its better signal-to-noise ratio. The non-contact sensor was then used to acquire in-vivo micro-CT images of a murine model for congenital diaphragmatic hernia and of 11-day-old mouse pups. In both cases, quality CT images were successfully acquired using this new respiration sensor. Despite the presence of beam hardening artefacts arising from the presence of a fibre-optic cable in the imaging field, we believe this new technique for respiration monitoring and gating presents an opportunity for in-vivo imaging of disease models which were previously considered too delicate for established animal handling methods. (paper)

  17. Antibiotics induce mitonuclear protein imbalance but fail to inhibit respiration and nutrient activation in pancreatic β-cells.

    Santo-Domingo, Jaime; Chareyron, Isabelle; Broenimann, Charlotte; Lassueur, Steve; Wiederkehr, Andreas

    2017-08-15

    Chloramphenicol and several other antibiotics targeting bacterial ribosomes inhibit mitochondrial protein translation. Inhibition of mitochondrial protein synthesis leads to mitonuclear protein imbalance and reduced respiratory rates as confirmed here in HeLa and PC12 cells. Unexpectedly, respiration in INS-1E insulinoma cells and primary human islets was unaltered in the presence of chloramphenicol. Resting respiratory rates and glucose stimulated acceleration of respiration were also not lowered when a range of antibiotics including, thiamphenicol, streptomycin, gentamycin and doxycycline known to interfere with bacterial protein synthesis were tested. However, chloramphenicol efficiently reduced mitochondrial protein synthesis in INS-1E cells, lowering expression of the mtDNA encoded COX1 subunit of the respiratory chain but not the nuclear encoded ATP-synthase subunit ATP5A. Despite a marked reduction of the essential respiratory chain subunit COX1, normal respiratory rates were maintained in INS-1E cells. ATP-synthase dependent respiration was even elevated in chloramphenicol treated INS-1E cells. Consistent with these findings, glucose-dependent calcium signaling reflecting metabolism-secretion coupling in beta-cells, was augmented. We conclude that antibiotics targeting mitochondria are able to cause mitonuclear protein imbalance in insulin secreting cells. We hypothesize that in contrast to other cell types, compensatory mechanisms are sufficiently strong to maintain normal respiratory rates and surprisingly even result in augmented ATP-synthase dependent respiration and calcium signaling following glucose stimulation. The result suggests that in insulin secreting cells only lowering COX1 below a threshold level may result in a measurable impairment of respiration. When focusing on mitochondrial function, care should be taken when including antibiotics targeting translation for long-term cell culture as depending on the sensitivity of the cell type analyzed

  18. Evaluation of protection factors of a breath-responsive-powered air-purifying respirator

    Nakagawa, Masahiro; Nojima, Shun; Fujii, Katsutoshi; Shishido, Nobuhito; Sakai, Toshiya; Umehara, Takashi; Shimizu, Isamu

    2012-01-01

    It is essential to wear an air-purifying respirator in the radiation works in a contaminated atmosphere. A breath-responsive-powered air-purifying respirator (BR-PAPR) has been recently developed. However, no research has yet been conducted to determine the protection factor (PF) of the BR-PAPR in actual workplaces. In this study, the PFs of the BR-PAPR were measured by a man-test apparatus and compared with those of a non-powered full face mask. The PFs were measured under three different situations; normal wearing condition, clogging the filter and leaving a gap between the face and the mask. Under these situations, it was found that the PFs of the BR-PAPR are higher than those of the non-powered full face mask. PFs greater than 4,000 were obtained for 95% of the subjects who wear the BR-PAPR, and PFs over 6,667, the upper limit of the man-test apparatus, were obtained for 49% of them. The questionnaire survey was conducted for workers. The results showed that the workers feel a reduced burden when they wear the BR-PAPR. The results of this study showed high protection performance and operation efficiency of the BR-PAPR. (author)

  19. Respiration in heterotrophic unicellular eukaryotic organisms.

    Fenchel, Tom

    2014-08-01

    Surface:volume quotient, mitochondrial volume fraction, and their distribution within cells were investigated and oxygen gradients within and outside cells were modelled. Cell surface increases allometrically with cell size. Mitochondrial volume fraction is invariant with cell size and constitutes about 10% and mitochondria are predominantly found close to the outer membrane. The results predict that for small and medium sized protozoa maximum respiration rates should be proportional to cell volume (scaling exponent ≈1) and access to intracellular O2 is not limiting except at very low ambient O2-tensions. Available data do not contradict this and some evidence supports this interpretation. Cell size is ultimately limited because an increasing fraction of the mitochondria becomes exposed to near anoxic conditions with increasing cell size. The fact that mitochondria cluster close to the cell surface and the allometric change in cell shape with increasing cell size alleviates the limitation of aerobic life at low ambient O2-tension and for large cell size. Copyright © 2014 Elsevier GmbH. All rights reserved.

  20. Contribution of root to soil respiration and carbon balance in ...

    PRAKASH

    improves our understanding of the terrestrial carbon cycle ... considerably lower net ecosystem productivity in Community 2 than in Community 1 .... soil respiration chambers for each time were dried at 31ºC ..... Using existing management.