WorldWideScience

Sample records for evaluate radiofrequency exposure

  1. 47 CFR 2.1091 - Radiofrequency radiation exposure evaluation: mobile devices.

    Science.gov (United States)

    2010-10-01

    ... 22 of this chapter, parts 24, 25, 26 and 27 of this chapter, part 80 of this chapter (ship earth... general population/uncontrolled exposure. (1) For purposes of analyzing mobile transmitting devices under... levels for devices intended for use by consumers in general population/uncontrolled environments as...

  2. 47 CFR 1.1310 - Radiofrequency radiation exposure limits.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Radiofrequency radiation exposure limits. 1... Procedures Implementing the National Environmental Policy Act of 1969 § 1.1310 Radiofrequency radiation... exposure to radiofrequency (RF) radiation as specified in § 1.1307(b), except in the case of portable...

  3. 78 FR 33633 - Human Exposure to Radiofrequency Electromagnetic Fields

    Science.gov (United States)

    2013-06-04

    ..., and 15, et al. Human Exposure to Radiofrequency Electromagnetic Fields; Reassessment of Exposure to Radiofrequency Electromagnetic Fields Limits and Policies; Final Rule and Proposed Rule #0;#0;Federal Register... Radiofrequency Electromagnetic Fields AGENCY: Federal Communications Commission. ACTION: Final rule. SUMMARY...

  4. 47 CFR 2.1093 - Radiofrequency radiation exposure evaluation: portable devices.

    Science.gov (United States)

    2010-10-01

    ... accomplished by use of warning labels or by specific training or education through appropriate means, such as... measurement techniques or by computational modeling. Methodologies and references for SAR evaluation are...-division multiple-access (TDMA) scheme for transmission of a signal. In general, maximum average power...

  5. An evaluation of safety guidelines to restrict exposure to stray radiofrequency radiation from short-wave diathermy units

    International Nuclear Information System (INIS)

    Shields, Nora; O'Hare, Neil; Gormley, John

    2004-01-01

    Short-wave diathermy (SWD), a form of radiofrequency radiation used therapeutically by physiotherapists, may be applied in continuous (CSWD) or pulsed (PSWD) mode using either capacitive or inductive methods. Stray radiation emitted by these units may exceed exposure guidelines close to the equipment. Discrepant guidelines exist on a safe distance from an operating unit for operators and other personnel. Stray electric (E-field) and magnetic (H-field) field strengths from 10 SWD units in six departments were examined using a PMM 8053 meter and two isotropic probes (EP-330, HP-032). A 5 l saline phantom completed the patient circuit. Measurements were recorded in eight directions between 0.5 m and 2 m at hip and eye levels while the units operated at maximum output and data compared to current guidelines. Results found stray fields from capacitive CSWD fell below operator limits at 2 m (E-field 4.8-39.8 V/m; H-field 0.015-0.072 A/m) and at 1 m for inductive CSWD (E-field 0-36 V/m; H-field 0.01-0.065 A/m). Capacitive PSWD fields fell below the limits at 1.5 m (E-field 1.2-19.9 V/m; H-field 0.002-0.045 A/m) and at 1m for inductive PSWD (E-field 0.7-4.0 V/m; H-field 0.009-0.03 A/m). An extra 0.5 m was required before fields fell below the guidelines for other personnel. These results demonstrate, under a worst case scenario, emissions from SWD exceed the guidelines for operators at distances currently recommended as safe. Future guidelines should include recommendations for personnel other than physiotherapists

  6. An evaluation of safety guidelines to restrict exposure to stray radiofrequency radiation from short-wave diathermy units

    Energy Technology Data Exchange (ETDEWEB)

    Shields, Nora [School of Physiotherapy, La Trobe University, Victoria 3086 (Australia); O' Hare, Neil [Department of Medical Physics and Bioengineering, St James' s Hospital, Dublin 8 (Ireland); Gormley, John [School of Physiotherapy, Trinity College Dublin, Trinity Centre for Health Sciences, St James' s Hospital, Dublin 8 (Ireland)

    2004-07-07

    Short-wave diathermy (SWD), a form of radiofrequency radiation used therapeutically by physiotherapists, may be applied in continuous (CSWD) or pulsed (PSWD) mode using either capacitive or inductive methods. Stray radiation emitted by these units may exceed exposure guidelines close to the equipment. Discrepant guidelines exist on a safe distance from an operating unit for operators and other personnel. Stray electric (E-field) and magnetic (H-field) field strengths from 10 SWD units in six departments were examined using a PMM 8053 meter and two isotropic probes (EP-330, HP-032). A 5 l saline phantom completed the patient circuit. Measurements were recorded in eight directions between 0.5 m and 2 m at hip and eye levels while the units operated at maximum output and data compared to current guidelines. Results found stray fields from capacitive CSWD fell below operator limits at 2 m (E-field 4.8-39.8 V/m; H-field 0.015-0.072 A/m) and at 1 m for inductive CSWD (E-field 0-36 V/m; H-field 0.01-0.065 A/m). Capacitive PSWD fields fell below the limits at 1.5 m (E-field 1.2-19.9 V/m; H-field 0.002-0.045 A/m) and at 1m for inductive PSWD (E-field 0.7-4.0 V/m; H-field 0.009-0.03 A/m). An extra 0.5 m was required before fields fell below the guidelines for other personnel. These results demonstrate, under a worst case scenario, emissions from SWD exceed the guidelines for operators at distances currently recommended as safe. Future guidelines should include recommendations for personnel other than physiotherapists.

  7. Occupational exposure of NRM spectrometrists to static and radiofrequency fields

    International Nuclear Information System (INIS)

    Berlana, Tania; Ubeda, Alejandro

    2017-01-01

    Occupational exposure to static and radiofrequency fields emitted by nuclear magnetic resonance spectrometers was assessed through systematic field metering during operation of 19 devices in nine research centers. Whereas no measurable levels of radiofrequency radiation were registered outside the spectrometers, significant exposure to static field was detected, with maximum values recorded at the user s hand (B = 683.00 mT) and head thorax (B = 135.70 mT) during spectrometer manipulation. All values were well below the exposure limits set by the European standard for workers protection against the effects of acute field exposure only. As for potential effects of chronic exposure, waiting for more complete knowledge, adoption of technical and operational strategies for exposure minimizing is advisable. In this respect, the data revealed that compared with standard magnetic shielding, ultra-shield technology allows a 20-65-fold reduction of the field strength received by the operator. (authors)

  8. Health Impacts Of Radiofrequency Exposure From Mobile Phone ...

    African Journals Online (AJOL)

    Background: The widespread use of mobile phones and indiscriminate siting of transmitter base stations near residential buildings in our environment may have serious health impacts. Objective: To investigate the possible health risks associated with radiofrequency (RF) exposure from mobile phones and other transmitter ...

  9. Health Impacts of Radiofrequency Exposure From Mobile Phones ...

    African Journals Online (AJOL)

    The widespread use of mobile phones and indiscriminate siting of transmitter base stations near residential buildings in our environment may have serious health impacts. This report attempts to investigate the possible health risks associated with radiofrequency (RF) exposure from mobile phones and their transmitter base ...

  10. Feasibility of a cohort study on health risks caused by occupational exposure to radiofrequency electromagnetic fields

    DEFF Research Database (Denmark)

    Breckenkamp, Jürgen; Berg-Beckhoff, Gabriele; Münster, Eva

    2009-01-01

    BACKGROUND: The aim of this study was to examine the feasibility of performing a cohort study on health risks from occupational exposure to radiofrequency electromagnetic fields (RF-EMF) in Germany. METHODS: A set of criteria was developed to evaluate the feasibility of such a cohort study...

  11. Risk assessment and management of radiofrequency radiation exposure

    International Nuclear Information System (INIS)

    Dabala, Dana; Surducan, Emanoil; Surducan, Vasile; Neamtu, Camelia

    2013-01-01

    Radiofrequency radiation (RFR) industry managers, occupational physicians, security department, and other practitioners must be advised on the basic of biophysics and the health effects of RF electromagnetic fields so as to guide the management of exposure. Information on biophysics of RFR and biological/heath effects is derived from standard texts, literature and clinical experiences. Emergency treatment and ongoing care is outlined, with clinical approach integrating the circumstances of exposure and the patient's symptoms. Experimental risk assessment model in RFR chronic exposure is proposed. Planning for assessment and monitoring exposure, ongoing care, safety measures and work protection are outlining the proper management

  12. Metallic implants and exposure to radiofrequency radiation

    International Nuclear Information System (INIS)

    Joyner, K.H.; Fleming, A.H.F.; MacFarlane, I.P.; Hocking, B.

    1988-01-01

    There is increasing use of radiofrequency radiation (RFR) in industry for communications, welding, security, radio, medicine, navigation etc. It has been recognised for some years that RFR may interact with cardiac pacemakers and steps have been taken to prevent this interference. It is less well recognised that other metallic implants may also act as antennas in an RFR field and possibly cause adverse health effects by heating local tissues. There are a large and increasing number of implants having metal components which may be found in RFR workers. These implants include artificial joints, rods and plates used in orthopaedics, rings in heart valves, wires in sutures, bionic ears, subcutaneous infusion systems and (external) transdermal drug delivery patches 1 . The physician concerned with job placement of such persons requires information on the likelihood of an implant interacting with RFR so as to impair health. The following outlines the approach developed in Telecom Australia, beginning with the general principles and then presenting a specific example discussion of a specific example

  13. Radiofrequency exposure in the Neonatal Medium Care Unit

    International Nuclear Information System (INIS)

    Calvente, I.; Vázquez-Pérez, A.; Fernández, M.F.; Núñez, M.I.; Múñoz-Hoyos, A.

    2017-01-01

    The aims of this study were to characterize electromagnetic fields of radiofrequency (RF-EMF) levels generated in a Neonatal Medium Care Unit and to analyze RF-EMF levels inside unit’s incubators. Spot and long-term measurements were made with a dosimeter. The spot measurement mean was 1.51±0.48 V/m. Higher values were found in the proximity to the window and to the incubator evaluated. Mean field strength for the entire period of 17 h was 0.81 (±0.07) V/m and the maximum value was 1.58 V/m for long-term RF-EMF measurements in the incubator. Values found during the night period were higher than those found during the day period. It is important to consider RF-EMF exposure levels in neonatal care units, due to some evidence of adverse health effects found in children and adults. Characterization of RF-EMF exposure may be important to further investigate the mechanisms and underlying effects of electromagnetic fields (EMF) on infant health. A prudent avoidance strategy should be adopted because newborns are at a vulnerable stage of development and the actual impact of EMF on premature infants is unknown. - Highlights: • The increasing use of RF-EMF suggests an urgent need for more research in this field. • Health consequences of RF-EMF exposure on infants are not well known. • Description of RF-EMF exposure is vital in further study mechanisms on infant health. • Considering newborns vulnerability, it is wise to adopt a prudent avoidance strategy.

  14. Measurement of Radiofrequency Radiation Exposure in Epidemiological Studies (invited paper)

    International Nuclear Information System (INIS)

    Swerdlow, A.J.

    1999-01-01

    The measurement of radiofrequency (RF) exposure is important to the quality of epidemiological studies of the possible association of RF exposure with disease. The extent and type of exposure measurement in past epidemiological studies of RF, and the features of measurement that would be desirable for better studies in the future are summarised. Measurement characteristics that are discussed include quantification of radiation frequency and of intensity and timing of exposures, measurement (or good estimation) of exposures for individuals rather than only for groups, quality of measurement, and measurement of RF exposures experienced outside the study setting. Integration of exposure measurement into the design of epidemiological studies is needed for better assessments of possible RF effects. (author)

  15. Radiofrequency fields: Bases for exposure limits

    International Nuclear Information System (INIS)

    Paolo Vecchia

    2006-01-01

    Several biological effects have been reported at exposure levels below the threshold for thermal effects, but most of them require independent confirmation before being accepted as established. However, no seems to have relevant implications for human health. Precautionary measures should be based on a cost/benefit analysis, and be proportionate on one side to the risk they aim at preventing and on the other side to actions taken in other areas to prevent comparable risks. (N.C.)

  16. Radiofrequency fields: Bases for exposure limits

    Energy Technology Data Exchange (ETDEWEB)

    Paolo Vecchia [Department of Technologies and Health National Institute of Health, Rome (Italy)

    2006-07-01

    Several biological effects have been reported at exposure levels below the threshold for thermal effects, but most of them require independent confirmation before being accepted as established. However, no seems to have relevant implications for human health. Precautionary measures should be based on a cost/benefit analysis, and be proportionate on one side to the risk they aim at preventing and on the other side to actions taken in other areas to prevent comparable risks. (N.C.)

  17. Objectivized evaluation of surgeons exposure to radiofrequency electromagnetic fields – In the context of exposure duration and polish and new international requirements regarding workers protection

    Directory of Open Access Journals (Sweden)

    Jolanta Karpowicz

    2013-08-01

    Full Text Available Background: Use of electro surgery units (ESU in surgeries is linked with electromagnetic field emission, which is assessed according to the requirements of occupational health and safety legislation. Material and Methods: Surgeons' exposure characteristics was monitored during 11 surgeries (proctectomy, patency of artery, hepatectomy, cystectomy, tonsilectomy, laparoscopy by real time of monopolar ESU activity recorder. Investigations of root-mean-square value of electric and magnetic field strength was also performed at various modes of ESU operations during cutting (output power, 55-150 W; frequency, 330-445 kHz and coagulating (40-240 W, 335-770 kHz. Statistical parameters of distribution of ESU operation over any 6-min periods (according to international requirements regarding protection against adverse thermal effects of electromagnetic field were assessed. Results: Electric field strength, measured 10 cm from the cable supplying an active electrode was 147-675 V/m during cutting and 297-558 V/m during coagulating; magnetic field strength was less than 0.2 A/m in both modes. Monitoring of ESUs showed the following ranges of their operation during surgeries 5-66% of time over starting 3 min of surgery, 3-40% over starting 6 min, and the distribution of their use over any 6-min periods 0-12% (median / 7-43% (maximum value. Conclusions: The real operation time of ESUs wykoduring surgeries was significantly shorter than that declared by workers. The distance of at least 15 cm between cables, connecting electrodes with generator and workers meets the requirements of the Polish legislation on permissible exposure limits. The assessment of localized exposure of the hand needs a detailed analysis of the SAR ratio distribution and further studies are required. Med Pr 2013;64(4:487–501

  18. Drone based measurement system for radiofrequency exposure assessment.

    Science.gov (United States)

    Joseph, Wout; Aerts, Sam; Vandenbossche, Matthias; Thielens, Arno; Martens, Luc

    2016-03-10

    For the first time, a method to assess radiofrequency (RF) electromagnetic field (EMF) exposure of the general public in real environments with a true free-space antenna system is presented. Using lightweight electronics and multiple antennas placed on a drone, it is possible to perform exposure measurements. This technique will enable researchers to measure three-dimensional RF-EMF exposure patterns accurately in the future and at locations currently difficult to access. A measurement procedure and appropriate measurement settings have been developed. As an application, outdoor measurements are performed as a function of height up to 60 m for Global System for Mobile Communications (GSM) 900 MHz base station exposure. Bioelectromagnetics. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  19. Radiofrequency radiation exposure from RF-generating plant

    International Nuclear Information System (INIS)

    Wright, J.M.; Bell, K.M.

    2000-01-01

    As part of an intervention to assist industry improve the control of risks associated with the use of RF-generating plant, exposure to radiofrequency radiation (RFR) was assessed in 30 workplaces. Information about the workplace, work practices and knowledge about RFR and its control was also collected. The study found that: 1. For 72% of operators and 35% of bystanders, the spatially averaged exposure exceeded the exposure limits. These figures approximately halved when the duty cycle was applied; 2. Assessment of RFR levels was not common; 3. Task rotation was used to limit exposure of operators; 4. Access was not controlled to areas where RFR sources were used; 5. There was lack of knowledge about RF shielding practices in industry; 6. Nearly 50% of workplaces did not maintain the plant regularly; and 7. There had been no health surveillance on any plant operators in any of the workplaces in the study. Copyright (2000) Australasian Radiation Protection Society Inc

  20. Radiofrequency exposure amongst employees of mobile network operators and broadcasters

    International Nuclear Information System (INIS)

    Litchfield, Ian; Sorahan, Tom; Tongeren, Martie van

    2017-01-01

    Little is known about personal exposure to radiofrequency (RF) fields amongst employees in the telecommunications industry responsible for installing and maintaining transmitters. IARC classified RF exposure as a possible carcinogen, although evidence from occupational studies was judged to be inadequate. Hence, there is a need for improved evidence of any potentially adverse health effects amongst the workforce occupationally exposed to RF radiation. In this study, results are presented from an exposure survey using data from personal monitors used by employees in the broadcasting and telecommunication industries of the UK. These data were supplemented by spot measurements using broadband survey metres and information on daily work activities provided by employee questionnaires. The sets of real-time personal data were categorised by four types of site determined by the highest powered antenna present (high, medium or low power and ground-level sites). For measurements gathered at each type of site, the root mean square and a series of box plots were produced. Results from the daily activities diaries suggested that riggers working for radio and television broadcasters were exposed to much longer periods as compared to colleagues working for mobile operators. Combining the results from the measurements and daily activity diaries clearly demonstrate that exposures were highest for riggers working for broadcasting sites. This study demonstrates that it is feasible to carry out exposure surveys within these populations that will provide reliable estimates of exposure that can be used for epidemiological studies of occupational groups exposed to RF fields. (authors)

  1. Radiofrequency (mobile telephones) Exposures and Health Risks: Findings and Controversies - Linet

    Science.gov (United States)

    Radiofrequency (mobile telephones) Exposures and Health Risks: Findings and Controversies by Dr. Martha Linet - part of the Radiation Epidemiology and Dosimetry Course on the health effects of radiation exposure

  2. Radiofrequency energy exposure from the Trilliant smart meter.

    Science.gov (United States)

    Foster, Kenneth R; Tell, Richard A

    2013-08-01

    This paper reviews radiofrequency (RF) field levels produced by electric utility meters equipped with RF transceivers (so-called Smart Meters), focusing on meters from one manufacturer (Trilliant, Redwood City, CA, USA, and Granby, QC, Canada). The RF transmission levels are summarized based on publicly available data submitted to the U.S. Federal Communications Commission supplemented by limited independent measurements. As with other Smart Meters, this meter incorporates a low powered radiofrequency transceiver used for a neighborhood mesh network, in the present case using ZigBee-compliant physical and medium access layers, operating in the 2.45 GHz unlicensed band but with a proprietary network architecture. Simple calculations based on a free space propagation model indicate that peak RF field intensities are in the range of 10 mW m or less at a distance of more than 1-2 m from the meters. However, the duty cycle of transmission from the meters is very low (meter that were consistent with data reported by the vendor to the U.S. Federal Communications Commission. Limited measurements conducted in two houses with the meters were unable to clearly distinguish emissions from the meters from the considerable electromagnetic clutter in the same frequency range from other sources, including Wi-Fi routers and, when it was activated, a microwave oven. These preliminary measurements disclosed the difficulties that would be encountered in characterizing the RF exposures from these meters in homes in the face of background signals from other household devices in the same frequency range. An appendix provides an introduction to Smart Meter technology. The RF transmitters in wireless-equipped Smart Meters operate at similar power levels and in similar frequency ranges as many other digital communications devices in common use, and their exposure levels are very far below U.S. and international exposure limits.

  3. Radiofrequency-electromagnetic field exposures in kindergarten children.

    Science.gov (United States)

    Bhatt, Chhavi Raj; Redmayne, Mary; Billah, Baki; Abramson, Michael J; Benke, Geza

    2017-09-01

    The aim of this study was to assess environmental and personal radiofrequency-electromagnetic field (RF-EMF) exposures in kindergarten children. Ten children and 20 kindergartens in Melbourne, Australia participated in personal and environmental exposure measurements, respectively. Order statistics of RF-EMF exposures were computed for 16 frequency bands between 88 MHz and 5.8 GHz. Of the 16 bands, the three highest sources of environmental RF-EMF exposures were: Global System for Mobile Communications (GSM) 900 MHz downlink (82 mV/m); Universal Mobile Telecommunications System (UMTS) 2100MHz downlink (51 mV/m); and GSM 900 MHz uplink (45 mV/m). Similarly, the three highest personal exposure sources were: GSM 900 MHz downlink (50 mV/m); UMTS 2100 MHz downlink, GSM 900 MHz uplink and GSM 1800 MHz downlink (20 mV/m); and Frequency Modulation radio, Wi-Fi 2.4 GHz and Digital Video Broadcasting-Terrestrial (10 mV/m). The median environmental exposures were: 179 mV/m (total all bands), 123 mV/m (total mobile phone base station downlinks), 46 mV/m (total mobile phone base station uplinks), and 16 mV/m (Wi-Fi 2.4 GHz). Similarly, the median personal exposures were: 81 mV/m (total all bands), 62 mV/m (total mobile phone base station downlinks), 21 mV/m (total mobile phone base station uplinks), and 9 mV/m (Wi-Fi 2.4 GHz). The measurements showed that environmental RF-EMF exposure levels exceeded the personal RF-EMF exposure levels at kindergartens.

  4. Radiofrequency Exposure Amongst Employees of Mobile Network Operators and Broadcasters.

    Science.gov (United States)

    Litchfield, Ian; van Tongeren, Martie; Sorahan, Tom

    2017-06-15

    Little is known about personal exposure to radiofrequency (RF) fields amongst employees in the telecommunications industry responsible for installing and maintaining transmitters. IARC classified RF exposure as a possible carcinogen, although evidence from occupational studies was judged to be inadequate. Hence, there is a need for improved evidence of any potentially adverse health effects amongst the workforce occupationally exposed to RF radiation. In this study, results are presented from an exposure survey using data from personal monitors used by employees in the broadcasting and telecommunication industries of the UK. These data were supplemented by spot measurements using broadband survey metres and information on daily work activities provided by employee questionnaires. The sets of real-time personal data were categorised by four types of site determined by the highest powered antenna present (high, medium or low power and ground-level sites). For measurements gathered at each type of site, the root mean square and a series of box plots were produced. Results from the daily activities diaries suggested that riggers working for radio and television broadcasters were exposed to much longer periods as compared to colleagues working for mobile operators. Combining the results from the measurements and daily activity diaries clearly demonstrate that exposures were highest for riggers working for broadcasting sites. This study demonstrates that it is feasible to carry out exposure surveys within these populations that will provide reliable estimates of exposure that can be used for epidemiological studies of occupational groups exposed to RF fields. © The Author 2016. Published by Oxford University Press.

  5. RADIOFREQUENCY AND MICROWAVE RADIATION HEALTH EFFECTS AND OCCUPATIONAL EXPOSURE

    Directory of Open Access Journals (Sweden)

    Ivana Damnjanović

    2011-12-01

    Full Text Available In the recent years, there have been considerable discussion and concern about the possible hazards of RF/MW radiation. More recently, the growth and development in personal mobile communications have focused attention on the frequencies associated with this technology. A number of studies have examined the health effects of RF/MW electromagnetic fields (EMFs, originating from occupational exposure, hobbies, or residence near the radio or television transmitters. Particularly controversial are the biophysical mechanisms by which these RF fields may affect biological systems. General health effects reviews explore possible carcinogenic, reproductive and neurological effects. Health effects by exposure source have been observed in radar traffic devices, wireless communications with cellular phones, radio transmission, and magnetic resonance imaging (MRI. Several epidemiological surveys have suggested associations with non-specific complaints such as headache, tiredness, sleep disturbance, loss of memory, and dizziness. These findings, which echo reports of illness associated with other types of radiofrequency (RF radiation, relate not only to the use of mobile phones, but also to residence near the mobile phone base stations and other settings involving occupational exposure. The biological effects suggest that some precautions are necessary, and preventive approaches are highly recommended. Further researches are required to give more information about the effects of microwave radiation on our health, especially in occupational setting and professionally exposed workers.

  6. Radiofrequency exposure from wireless LANs utilizing Wi-Fi technology.

    Science.gov (United States)

    Foster, Kenneth R

    2007-03-01

    This survey measured radiofrequency (RF) fields from wireless local area networks (WLANs) using Wi-Fi technology against a background of RF fields in the environment over the frequency range 75 MHz-3 GHz. A total of 356 measurements were conducted at 55 sites (including private residences, commercial spaces, health care and educational institutions, and other public spaces) in four countries (U.S., France, Germany, Sweden). Measurements were conducted under conditions that would result in the higher end of exposures from such systems. Where possible, measurements were conducted in public spaces as close as practical to the Wi-Fi access points. Additional measurements were conducted at a distance of approximately 1 m from a laptop while it was uploading and downloading large files to the WLAN. This distance was chosen to allow a useful comparison of fields in the far-field of the antenna in the laptop, and give a representative measure of the exposure that a bystander might receive from the laptop. The exposure to the user, particularly if the antenna of the client card were placed against his or her body, would require different measurement techniques beyond the scope of this study. In all cases, the measured Wi-Fi signal levels were very far below international exposure limits (IEEE C95.1-2005 and ICNIRP) and in nearly all cases far below other RF signals in the same environments. An discusses technical aspects of the IEEE 802.11 standard on which WLANs operate that are relevant to determining the levels of RF energy exposure from WLANs. Important limiting factors are the low operating power of client cards and access points, and the low duty cycle of transmission that normally characterizes their operation.

  7. Effects of Cell Phone Radiofrequency Signal Exposure on Brain Glucose Metabolism

    Science.gov (United States)

    Volkow, Nora D.; Tomasi, Dardo; Wang, Gene-Jack; Vaska, Paul; Fowler, Joanna S.; Telang, Frank; Alexoff, Dave; Logan, Jean; Wong, Christopher

    2011-01-01

    Context The dramatic increase in use of cellular telephones has generated concern about possible negative effects of radiofrequency signals delivered to the brain. However, whether acute cell phone exposure affects the human brain is unclear. Objective To evaluate if acute cell phone exposure affects brain glucose metabolism, a marker of brain activity. Design, Setting, and Participants Randomized crossover study conducted between January 1 and December 31, 2009, at a single US laboratory among 47 healthy participants recruited from the community. Cell phones were placed on the left and right ears and positron emission tomography with (18F)fluorodeoxyglucose injection was used to measure brain glucose metabolism twice, once with the right cell phone activated (sound muted) for 50 minutes (“on” condition) and once with both cell phones deactivated (“off” condition). Statistical parametric mapping was used to compare metabolism between on and off conditions using paired t tests, and Pearson linear correlations were used to verify the association of metabolism and estimated amplitude of radiofrequency-modulated electromagnetic waves emitted by the cell phone. Clusters with at least 1000 voxels (volume >8 cm3) and P cell phone exposure was associated with increased brain glucose metabolism in the region closest to the antenna. This finding is of unknown clinical significance. PMID:21343580

  8. Activation of the TRPV1 Thermoreceptor Induced by Modulated or Unmodulated 1800 MHz Radiofrequency Field Exposure.

    Science.gov (United States)

    Ruigrok, Hermanus J; Arnaud-Cormos, Delia; Hurtier, Annabelle; Poque, Emmanuelle; de Gannes, Florence Poulletier; Ruffié, Gilles; Bonnaudin, Fabrice; Lagroye, Isabelle; Sojic, Neso; Arbault, Stéphane; Lévêque, Philippe; Veyret, Bernard; Percherancier, Yann

    2018-01-01

    The existence of effects of radiofrequency field exposure at environmental levels on living tissues and organisms remains controversial, in particular regarding potential "nonthermal" effects produced in the absence of temperature elevation. Therefore, we investigated whether TRPV1, one of the most studied thermosensitive channels, can be activated by the heat produced by radiofrequency fields and by some specific nonthermal interaction with the fields. We have recently shown that TRPV1 activation can be assessed in real-time on live cells using the bioluminescence resonance energy transfer technique. Taking advantage of this innovative assay, we monitored TRPV1 thermal and chemical modes of activation under radiofrequency exposure at 1800 MHz using different signals (CW, GSM, UMTS, LTE, Wi-Fi and WiMAX) at specific absorption rates between 8 and 32 W/kg. We showed that, as expected, TRPV1 channels were activated by the heat produced by radiofrequency field exposure of transiently-transfected HEK293T cells, but found no evidence of TRPV1 activation in the absence of temperature elevation under radiofrequency field exposure. There was no evidence either that, at fixed temperature, radiofrequency exposure altered the maximal efficacy of the agonist Capsaicin to activate TRPV1.

  9. Instruments to assess and measure personal and environmental radiofrequency-electromagnetic field exposures

    International Nuclear Information System (INIS)

    Bhatt, Chhavi R.; Redmayne, Mary; Abramson, Michael J.; Benke, Geza

    2016-01-01

    Radiofrequency-electromagnetic field (RF-EMF) exposure of human populations is increasing due to the widespread use of mobile phones and other telecommunication and broadcasting technologies. There are ongoing concerns about potential short- and long-term public health consequences from RF-EMF exposures. To elucidate the RF-EMF exposure-effect relationships, an objective evaluation of the exposures with robust assessment tools is necessary. This review discusses and compares currently available RF-EMF exposure assessment instruments, which can be used in human epidemiological studies. Quantitative assessment instruments are either mobile phone-based (apps/software-modified and hardware-modified) or exposimeters. Each of these tool has its usefulness and limitations. Our review suggests that assessment of RF-EMF exposures can be improved by using these tools compared to the proxy measures of exposure (e.g. questionnaires and billing records). This in turn, could be used to help increase knowledge about RF-EMF exposure induced health effects in human populations.

  10. Instruments to assess and measure personal and environmental radiofrequency-electromagnetic field exposures.

    Science.gov (United States)

    Bhatt, Chhavi Raj; Redmayne, Mary; Abramson, Michael J; Benke, Geza

    2016-03-01

    Radiofrequency-electromagnetic field (RF-EMF) exposure of human populations is increasing due to the widespread use of mobile phones and other telecommunication and broadcasting technologies. There are ongoing concerns about potential short- and long-term public health consequences from RF-EMF exposures. To elucidate the RF-EMF exposure-effect relationships, an objective evaluation of the exposures with robust assessment tools is necessary. This review discusses and compares currently available RF-EMF exposure assessment instruments, which can be used in human epidemiological studies. Quantitative assessment instruments are either mobile phone-based (apps/software-modified and hardware-modified) or exposimeters. Each of these tool has its usefulness and limitations. Our review suggests that assessment of RF-EMF exposures can be improved by using these tools compared to the proxy measures of exposure (e.g. questionnaires and billing records). This in turn, could be used to help increase knowledge about RF-EMF exposure induced health effects in human populations.

  11. Survey of radiofrequency radiation levels around GSM base stations and evaluation of measurement uncertainty

    Directory of Open Access Journals (Sweden)

    Vulević Branislav D.

    2011-01-01

    Full Text Available This paper is a summary of broadband measurement values of radiofrequency radiation around GSM base stations in the vicinity of residential areas in Belgrade and 12 other cities in Serbia. It will be useful for determining non-ionizing radiation exposure levels of the general public in the future. The purpose of this paper is also an appropriate representation of basic information on the evaluation of measurement uncertainty.

  12. Evaluation of stray radiofrequency radiation emitted by electrosurgical devices

    International Nuclear Information System (INIS)

    De Marco, M; Maggi, S

    2006-01-01

    Electrosurgery refers to the passage of a high-frequency, high-voltage electrical current through the body to achieve the desired surgical effects. At the same time, these procedures are accompanied by a general increase of the electromagnetic field in an operating room that may expose both patients and personnel to relatively high levels of radiofrequency radiation. In the first part of this study, we have taken into account the radiation emitted by different monopolar electrosurgical devices, evaluating the electromagnetic field strength delivered by an electrosurgical handle and straying from units and other electrosurgical accessories. As a summary, in the worst case a surgeon's hands are exposed to a continuous and pulsed RF wave whose magnetic field strength is 0.75 A m -1 (E-field 400 V m -1 ). Occasionally stray radiation may exceed ICNIRP's occupational exposure guidelines, especially close to the patient return plate. In the second part of this paper, we have analysed areas of particular concern to prevent electromagnetic interference with some life-support devices (ventilators and electrocardiographic devices), which have failed to operate correctly. Most clinically relevant interference occurred when an electrosurgery device was used within 0.3 m of medical equipment. In the appendix, we suggest some practical recommendations intended to minimize the potential for electromagnetic hazards due to therapeutic application of RF energy

  13. Public Exposure from Indoor Radiofrequency Radiation in the City of Hebron, West Bank-Palestine.

    Science.gov (United States)

    Lahham, Adnan; Sharabati, Afefeh; ALMasri, Hussien

    2015-08-01

    This work presents the results of measured indoor exposure levels to radiofrequency (RF) radiation emitting sources in one of the major cities in the West Bank-the city of Hebron. Investigated RF emitters include FM, TV broadcasting stations, mobile telephony base stations, cordless phones [Digital Enhanced Cordless Telecommunications (DECT)], and wireless local area networks (WLAN). Measurements of power density were conducted in 343 locations representing different site categories in the city. The maximum total power density found at any location was about 2.3 × 10 W m with a corresponding exposure quotient of about 0.01. This value is well below unity, indicating compliance with the guidelines of the International Commission on Non-ionizing Radiation Protection (ICNIRP). The average total exposure from all RF sources was 0.08 × 10 W m. The relative contributions from different sources to the total exposure in terms of exposure quotient were evaluated and found to be 46% from FM radio, 26% from GSM900, 15% from DECT phones, 9% from WLAN, 3% from unknown sources, and 1% from TV broadcasting. RF sources located outdoors contribute about 73% to the population exposure indoors.

  14. The role of the location of personal exposimeters on the human body in their use for assessing exposure to the electromagnetic field in the radiofrequency range 98-2450 MHz and compliance analysis: evaluation by virtual measurements.

    Science.gov (United States)

    Gryz, Krzysztof; Zradziński, Patryk; Karpowicz, Jolanta

    2015-01-01

    The use of radiofrequency (98-2450 MHz range) personal exposimeters to measure the electric field (E-field) in far-field exposure conditions was modelled numerically using human body model Gustav and finite integration technique software. Calculations with 256 models of exposure scenarios show that the human body has a significant influence on the results of measurements using a single body-worn exposimeter in various locations near the body ((from -96 to +133)%, measurement errors with respect to the unperturbed E-field value). When an exposure assessment involves the exposure limitations provided for the strength of an unperturbed E-field. To improve the application of exposimeters in compliance tests, such discrepancies in the results of measurements by a body-worn exposimeter may be compensated by using of a correction factor applied to the measurement results or alternatively to the exposure limit values. The location of a single exposimeter on the waist to the back side of the human body or on the front of the chest reduces the range of exposure assessments uncertainty (covering various exposure conditions). However, still the uncertainty of exposure assessments using a single exposimeter remains significantly higher than the assessment of the unperturbed E-field using spot measurements.

  15. Effects of Cell Phone Radiofrequency Signal Exposure on Brain Glucos Metabolism

    International Nuclear Information System (INIS)

    Volkow, N.D.; Tomasi, D.; Wang, G.-J.; Vaska, P.; Fowler, J.S.; Telang, F.; Alexoff, D.; Logan, J.; Wong, C.

    2011-01-01

    The dramatic increase in use of cellular telephones has generated concern about possible negative effects of radiofrequency signals delivered to the brain. However, whether acute cell phone exposure affects the human brain is unclear. To evaluate if acute cell phone exposure affects brain glucose metabolism, a marker of brain activity. Randomized crossover study conducted between January 1 and December 31, 2009, at a single US laboratory among 47 healthy participants recruited from the community. Cell phones were placed on the left and right ears and positron emission tomography with ( 18 F)fluorodeoxyglucose injection was used to measure brain glucose metabolism twice, once with the right cell phone activated (sound muted) for 50 minutes ('on' condition) and once with both cell phones deactivated ('off' condition). Statistical parametric mapping was used to compare metabolism between on and off conditions using paired t tests, and Pearson linear correlations were used to verify the association of metabolism and estimated amplitude of radiofrequency-modulated electromagnetic waves emitted by the cell phone. Clusters with at least 1000 voxels (volume >8 cm 3 ) and P < .05 (corrected for multiple comparisons) were considered significant. Brain glucose metabolism computed as absolute metabolism ((micro)mol/100 g per minute) and as normalized metabolism (region/whole brain). Whole-brain metabolism did not differ between on and off conditions. In contrast, metabolism in the region closest to the antenna (orbitofrontal cortex and temporal pole) was significantly higher for on than off conditions (35.7 vs 33.3 (micro)mol/100 g per minute; mean difference, 2.4 (95% confidence interval, 0.67-4.2); P = .004). The increases were significantly correlated with the estimated electromagnetic field amplitudes both for absolute metabolism (R = 0.95, P < .001) and normalized metabolism (R = 0.89; P < .001). In healthy participants and compared with no exposure, 50-minute cell phone

  16. Effects of Cell Phone Radiofrequency Signal Exposure on Brain Glucos Metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Volkow, N.D.; Wang, G.; Volkow, N.D.; Tomasi, D.; Wang, G.-J.; Vaska, P.; Fowler, J.S.; Telang, F.; Alexoff, D.; Logan, J.; Wong, C.

    2011-03-01

    The dramatic increase in use of cellular telephones has generated concern about possible negative effects of radiofrequency signals delivered to the brain. However, whether acute cell phone exposure affects the human brain is unclear. To evaluate if acute cell phone exposure affects brain glucose metabolism, a marker of brain activity. Randomized crossover study conducted between January 1 and December 31, 2009, at a single US laboratory among 47 healthy participants recruited from the community. Cell phones were placed on the left and right ears and positron emission tomography with ({sup 18}F)fluorodeoxyglucose injection was used to measure brain glucose metabolism twice, once with the right cell phone activated (sound muted) for 50 minutes ('on' condition) and once with both cell phones deactivated ('off' condition). Statistical parametric mapping was used to compare metabolism between on and off conditions using paired t tests, and Pearson linear correlations were used to verify the association of metabolism and estimated amplitude of radiofrequency-modulated electromagnetic waves emitted by the cell phone. Clusters with at least 1000 voxels (volume >8 cm{sup 3}) and P < .05 (corrected for multiple comparisons) were considered significant. Brain glucose metabolism computed as absolute metabolism ({micro}mol/100 g per minute) and as normalized metabolism (region/whole brain). Whole-brain metabolism did not differ between on and off conditions. In contrast, metabolism in the region closest to the antenna (orbitofrontal cortex and temporal pole) was significantly higher for on than off conditions (35.7 vs 33.3 {micro}mol/100 g per minute; mean difference, 2.4 [95% confidence interval, 0.67-4.2]; P = .004). The increases were significantly correlated with the estimated electromagnetic field amplitudes both for absolute metabolism (R = 0.95, P < .001) and normalized metabolism (R = 0.89; P < .001). In healthy participants and compared with no

  17. Short-duration exposure to radiofrequency electromagnetic radiation alters the chlorophyll fluorescence of duckweeds (Lemna minor).

    Science.gov (United States)

    Senavirathna, Mudalige Don Hiranya Jayasanka; Takashi, Asaeda; Kimura, Yuichi

    2014-12-01

    Plants growing in natural environments are exposed to radiofrequency electromagnetic radiation (EMR) emitted by various communication network base stations. The environmental concentration of this radiation is increasing rapidly with the congested deployment of base stations. Although numerous scientific studies have been conducted to investigate the effects of EMR on the physiology of humans and animals, there have been few attempts to investigate the effects of EMR on plants. In this study, we attempted to evaluate the effects of EMR on photosynthesis by investigating the chlorophyll fluorescence (ChF) parameters of duckweed fronds. During the experiment, the fronds were tested with 2, 2.5, 3.5, 5.5 and 8 GHz EMR frequencies, which are not widely studied even though there is a potentially large concentration of these frequencies in the environment. The duckweed fronds were exposed to EMR for 30 min, 1 h and 24 h durations with electric field strength of 45-50 V/m for each frequency. The results indicated that exposure to EMR causes a change in the non-photochemical quenching of the duckweeds. The changes varied with the frequency of the EMR and were time-varying within a particular frequency. The temperature remained unchanged in the duckweed fronds upon exposure to EMR, which confirms that the effect is non-thermal.

  18. Effects of radiofrequency radiation exposure on blood-brain barrier permeability in male and female rats.

    Science.gov (United States)

    Sirav, Bahriye; Seyhan, Nesrin

    2011-12-01

    During the last several decades, numerous studies have been performed aiming at the question of whether or not exposure to radiofrequency radiation (RFR) influences the permeability of the blood-brain barrier (BBB). The objective of this study was to investigate the effect of RFR on the permeability of BBB in male and female Wistar albino rats. Right brain, left brain, cerebellum, and total brain were analyzed separately in the study. Rats were exposed to 0.9 and 1.8 GHz continuous-wave (CW) RFR for 20 min (at SARs of 4.26 mW/kg and 1.46 mW/kg, respectively) while under anesthesia. Control rats were sham-exposed. Disruption of BBB integrity was detected spectrophotometrically using the Evans-blue dye, which has been used as a BBB tracer and is known to be bound to serum albumin. Right brain, left brain, cerebellum, and total brain were evaluated for BBB permeability. In female rats, no albumin extravasation was found in in the brain after RFR exposure. A significant increase in albumin was found in the brains of the RF-exposed male rats when compared to sham-exposed male brains. These results suggest that exposure to 0.9 and 1.8 GHz CW RFR at levels below the international limits can affect the vascular permeability in the brain of male rats. The possible risk of RFR exposure in humans is a major concern for the society. Thus, this topic should be investigated more thoroughly in the future.

  19. Exposure to radio-frequency electromagnetic fields and behavioural problems in Bavarian children and adolescents.

    Science.gov (United States)

    Thomas, Silke; Heinrich, Sabine; von Kries, Rüdiger; Radon, Katja

    2010-02-01

    Only few studies have so far investigated possible health effects of radio-frequency electromagnetic fields (RF EMF) in children and adolescents, although experts discuss a potential higher vulnerability to such fields. We aimed to investigate a possible association between measured exposure to RF EMF fields and behavioural problems in children and adolescents. 1,498 children and 1,524 adolescents were randomly selected from the population registries of four Bavarian (South of Germany) cities. During an Interview data on participants' mental health, socio-demographic characteristics and potential confounders were collected. Mental health behaviour was assessed using the German version of the Strengths and Difficulties Questionnaire (SDQ). Using a personal dosimeter, we obtained radio-frequency EMF exposure profiles over 24 h. Exposure levels over waking hours were expressed as mean percentage of the reference level. Overall, exposure to radiofrequency electromagnetic fields was far below the reference level. Seven percent of the children and 5% of the adolescents showed an abnormal mental behaviour. In the multiple logistic regression analyses measured exposure to RF fields in the highest quartile was associated to overall behavioural problems for adolescents (OR 2.2; 95% CI 1.1-4.5) but not for children (1.3; 0.7-2.6). These results are mainly driven by one subscale, as the results showed an association between exposure and conduct problems for adolescents (3.7; 1.6-8.4) and children (2.9; 1.4-5.9). As this is one of the first studies that investigated an association between exposure to mobile telecommunication networks and mental health behaviour more studies using personal dosimetry are warranted to confirm these findings.

  20. Exposure to radio-frequency electromagnetic fields and behavioural problems in Bavarian children and adolescents

    International Nuclear Information System (INIS)

    Thomas, Silke; Heinrich, Sabine; Kries, Ruediger von; Radon, Katja

    2010-01-01

    Only few studies have so far investigated possible health effects of radio-frequency electromagnetic fields (RF EMF) in children and adolescents, although experts discuss a potential higher vulnerability to such fields. We aimed to investigate a possible association between measured exposure to RF EMF fields and behavioural problems in children and adolescents. 1,498 children and 1,524 adolescents were randomly selected from the population registries of four Bavarian (South of Germany) cities. During an Interview data on participants' mental health, socio-demographic characteristics and potential confounders were collected. Mental health behaviour was assessed using the German version of the Strengths and Difficulties Questionnaire (SDQ). Using a personal dosimeter, we obtained radio-frequency EMF exposure profiles over 24 h. Exposure levels over waking hours were expressed as mean percentage of the reference level. Overall, exposure to radiofrequency electromagnetic fields was far below the reference level. Seven percent of the children and 5% of the adolescents showed an abnormal mental behaviour. In the multiple logistic regression analyses measured exposure to RF fields in the highest quartile was associated to overall behavioural problems for adolescents (OR 2.2; 95% CI 1.1-4.5) but not for children (1.3; 0.7-2.6). These results are mainly driven by one subscale, as the results showed an association between exposure and conduct problems for adolescents (3.7; 1.6-8.4) and children (2.9; 1.4-5.9). As this is one of the first studies that investigated an association between exposure to mobile telecommunication networks and mental health behaviour more studies using personal dosimetry are warranted to confirm these findings.

  1. Residential characteristics and radiofrequency electromagnetic field exposures from bedroom measurements in Germany

    DEFF Research Database (Denmark)

    Breckenkamp, J; Blettner, M; Schüz, J

    2012-01-01

    The objectives of this study were to assess total exposure to radiofrequency electromagnetic fields (RF-EMF) in bedrooms and the contribution of different radioservices (FM radio, analogue TV and DVB-T, TETRA, GSM900 downlink, GSM1800 downlink, UMTS downlink, DECT, and wireless LAN and blue tooth...... Antennessa(®) EME Spy 120 dosimeters in 1,348 households in Germany; 280 measures were available for each frequency band per household. Mean electrical field strengths and power flux densities were calculated. Power flux densities allow the calculation of proportions of different radioservices on total...... exposure. Exposure was often below the detection limit (electrical field strength: 0.05 V/m) of the dosimeter. Total exposure varied, depending on residential characteristics (urban vs. rural areas and floor of a building the measurement took place). Major sources of exposure were cordless phones (DECT...

  2. Evaluation of cellular effects of pulsed and continuous wave radiofrequency radiation

    International Nuclear Information System (INIS)

    Pavicic, Ivan; Trosic, Ivancica

    2008-01-01

    Full text: In less than twenty years, the mobile telephone has gone from being rare, expensive equipment of the business elite to a pervasive, low-cost personal item. Since the introduction of mobile phones, concerns have been raised about the potential detrimental impacts on living beings from regular use. The first 'modern' network technology on second generation cellular technology was launched in 1991 in Finland on the Global System for Mobile Communications (GSM) standard. This study evaluates cellular effects of, both, continuous (CW) and pulsed GSM modulated waves (PW). Continuous cell culture of Chinese hamster lung cells, line V79, was used in this study. Cell growth and colony forming ability (CFA) was analyzed after 1, 2 and 3 hours of exposure to the both frequency fields, 935 MHz CW and 915 MHz PW. Selected frequency fields were generated inside gigahertz transversal electromagnetic mode cell (GTEM) equipped with the signal generators. Hewlett Packard HP8657A signal generator was used to generate CW 935 MHz frequency field. Anritzu MS2711B spectrum analyzer with tracking generator and Micro devices RF 3146 power amplifier module generated PW radiofrequency field of 915 MHz. Averaged specific absorption rate (SAR) belonging to the CW 935 MHz frequency field was calculated to be 0.12 W/kg, and for GSM modulated 915 MHz field was 0.23 W/kg. Cell samples were irradiated in triplicate. The sham exposed control cell samples were included in the study. The temperature inside the exposure set-up was recorded in ten-minute intervals through the irradiation treatment. Both, sham-exposed and exposed cell samples were kept in the same condition, except in the time of irradiation for experimental samples when signal generator was switched on. To determine cell growth, V79 samples were plated in concentration of 1x10 4 cells/mL. Cells were maintained in the standard laboratory conditions, which are humidified atmosphere, 37 C degrees, and 5% CO 2 . Cell

  3. Impact of one's own mobile phone in stand-by mode on personal radiofrequency electromagnetic field exposure.

    Science.gov (United States)

    Urbinello, Damiano; Röösli, Martin

    2013-01-01

    When moving around, mobile phones in stand-by mode periodically send data about their positions. The aim of this paper is to evaluate how personal radiofrequency electromagnetic field (RF-EMF) measurements are affected by such location updates. Exposure from a mobile phone handset (uplink) was measured during commuting by using a randomized cross-over study with three different scenarios: disabled mobile phone (reference), an activated dual-band phone and a quad-band phone. In the reference scenario, uplink exposure was highest during train rides (1.19 mW/m(2)) and lowest during car rides in rural areas (0.001 mW/m(2)). In public transports, the impact of one's own mobile phone on personal RF-EMF measurements was not observable because of high background uplink radiation from other people's mobile phone. In a car, uplink exposure with an activated phone was orders of magnitude higher compared with the reference scenario. This study demonstrates that personal RF-EMF exposure is affected by one's own mobile phone in stand-by mode because of its regular location update. Further dosimetric studies should quantify the contribution of location updates to the total RF-EMF exposure in order to clarify whether the duration of mobile phone use, the most common exposure surrogate in the epidemiological RF-EMF research, is actually an adequate exposure proxy.

  4. Adaptive Response Induced by PreExposure to 915 MHz Radiofrequency: A Possible Role for Antioxidant Enzyme Activity

    Directory of Open Access Journals (Sweden)

    Mortazavi S. M. J.

    2017-06-01

    Full Text Available Background: Over the past few years, the rapid use of high frequency electromagnetic fields like mobile phones has raised global concerns about the negative health effects of its use. Adaptive response is the ability of a cell or tissue to better resist stress damage by prior exposure to a lesser amount of stress. This study aimed to assess whether radiofrequency radiation can induce adaptive response by changing the antioxidant balance. Materials and Methods: In order to assess RF-induced adaptive response in tissues, we evaluated the level of GSH and the activity of GR in liver. 50 rats were divided into 5 groups. Three groups were pre-exposed to 915 MHz RF radiation, 4 hours per day for one week at different powers, as low, medium and high. 24 hours after the last exposure to radiation, they were exposed to 4 Gy sublethal dose of gamma radiation and then sacrificed after 5 hours. Their livers were removed, washed and were kept at -80o C until used. Results: Our finding showed that pre-exposure to 915 MHz radiofrequency radiation with specific power could induce adaptive response in liver by inducing changes in the activity and level of antioxidant enzymes. Conclusion: It can be concluded that pre-exposure to microwave radiation could increase the level of GSH and the activity of GR enzyme, although these increases were seen just in low power group, and the GR activity was indicated in medium power group. This increase protects tissue from oxidative damage induced by sublethal dose of gamma radiation.

  5. Sources of exposure to radiofrequency and microwave radiations in the UK

    CERN Document Server

    Allen, S G

    1983-01-01

    A comprehensive survey is presented of sources of radiofrequency and microwave fields in the United Kingdom that give rise to the exposure of both workers and the general public. The information is presented in the context of the existing guidelines for the restrictions of exposures to such fields and of proposed new guidelines based on restricting the rate of energy absorption averaged over the human body to 0.4 watts per kilogram or, at frequencies below 3 MHz, limiting field strengths to 600 volts per metre. It is concluded that unless account is taken of time averaging relaxations and possible modifying factors relating to energy absorption arising under near field and partial body exposure conditions, there may be difficulties in applying the proposed guidelines to the use of radio frequencies for industrial heating purposes and to some portable and mobile transmitters used for communications.

  6. Increased Microleakage of Amalgam Restorations after Exposure to 2.4 Ghz Radiofrequency Electromagnetic Fields from Common Wi-Fi Routers

    Directory of Open Access Journals (Sweden)

    Mortazavi SMJ

    2017-09-01

    Full Text Available Statement of Problem: Previous studies have shown that exposure of dental amalgam fillings to MRI and mobile phones can increase microleakage of amalgam restorations. Objectives: The aim of this study was to evaluate the effects of exposure to radiofrequency radiation emitted from indoor Wi-Fi access devices on microleakage of amalgam restorations. Materials and Methods: Standard class V cavities were prepared on the buccal surfaces of 69 extracted human premolar teeth. The samples were divided into two exposure groups and one non-exposed control group of 23 teeth each. The specimens in the experimental groups were exposed to a radiofrequency (RF radiation emitted from a commercial 2.4 GHz Wi Fi router. The distance between the Wi-Fi router and samples was 30 cm and the router was exchanging data with a laptop computer that was placed 20 m away from the router. Teeth samples in the first exposure group (group A were exposed to RF for 3 days while the second exposure group (group B was exposed for 6 days. Then the teeth were sectioned and scored for microleakage under a stereomicroscope. Results: The score of microleakage was significantly higher in the exposure group A compared to that of the control group. However, the score of microleakage was not significantly different between the exposure group B and control group. Furthermore, the scores of microleakage was signifi-cantly higher in the exposure group A than that of the exposure group B. Conclusions: Exposure of patients with amalgam restorations to radiofre-quency waves emitted from commercial Wi-Fi routers can lead to in-creased microleakage of amalgam restorations.

  7. Histopomorphic evaluation of radiofrequency mediated débridement chondroplasty.

    Science.gov (United States)

    Ganguly, Kumkum; McRury, Ian D; Goodwin, Peter M; Morgan, Roy E; Augé Ii, Wayne K

    2010-06-29

    The use of radiofrequency devices has become widespread for surgical ablation procedures. When ablation devices have been deployed in treatment settings requiring tissue preservation like débridement chondroplasty, adoption has been limited due to the collateral damage caused by these devices in healthy tissue surrounding the treatment site. Ex vivo radiofrequency mediated débridement chondroplasty was performed on osteochondral specimens demonstrating surface fibrillation obtained from patients undergoing knee total joint replacement. Three radiofrequency systems designed to perform débridement chondroplasty were tested each demonstrating different energy delivery methods: monopolar ablation, bipolar ablation, and non-ablation energy. Treatment outcomes were compared with control specimens as to clinical endpoint and histopomorphic characteristics. Fibrillated cartilage was removed in all specimens; however, the residual tissue remaining at the treatment site displayed significantly different characteristics attributable to radiofrequency energy delivery method. Systems that delivered ablation-based energies caused tissue necrosis and collateral damage at the treatment site including corruption of cartilage Superficial and Transitional Zones; whereas, the non-ablation system created a smooth articular surface with Superficial Zone maintenance and without chondrocyte death or tissue necrosis. The mechanism of radiofrequency energy deposition upon tissues is particularly important in treatment settings requiring tissue preservation. Ablation-based device systems can cause a worsened state of articular cartilage from that of pre-treatment. Non-ablation energy can be successful in modifying/preconditioning tissue during débridement chondroplasty without causing collateral damage. Utilizing a non-ablation radiofrequency system provides the ability to perform successful débridement chondroplasty without causing additional articular cartilage tissue damage and may

  8. Histopomorphic Evaluation of Radiofrequency Mediated Débridement Chondroplasty

    Science.gov (United States)

    Ganguly, Kumkum; McRury, Ian D; Goodwin, Peter M; Morgan, Roy E; Augé II, Wayne K

    2010-01-01

    The use of radiofrequency devices has become widespread for surgical ablation procedures. When ablation devices have been deployed in treatment settings requiring tissue preservation like débridement chondroplasty, adoption has been limited due to the collateral damage caused by these devices in healthy tissue surrounding the treatment site. Ex vivo radiofrequency mediated débridement chondroplasty was performed on osteochondral specimens demonstrating surface fibrillation obtained from patients undergoing knee total joint replacement. Three radiofrequency systems designed to perform débridement chondroplasty were tested each demonstrating different energy delivery methods: monopolar ablation, bipolar ablation, and non-ablation energy. Treatment outcomes were compared with control specimens as to clinical endpoint and histopomorphic characteristics. Fibrillated cartilage was removed in all specimens; however, the residual tissue remaining at the treatment site displayed significantly different characteristics attributable to radiofrequency energy delivery method. Systems that delivered ablation-based energies caused tissue necrosis and collateral damage at the treatment site including corruption of cartilage Superficial and Transitional Zones; whereas, the non-ablation system created a smooth articular surface with Superficial Zone maintenance and without chondrocyte death or tissue necrosis. The mechanism of radiofrequency energy deposition upon tissues is particularly important in treatment settings requiring tissue preservation. Ablation-based device systems can cause a worsened state of articular cartilage from that of pre-treatment. Non-ablation energy can be successful in modifying/preconditioning tissue during débridement chondroplasty without causing collateral damage. Utilizing a non-ablation radiofrequency system provides the ability to perform successful débridement chondroplasty without causing additional articular cartilage tissue damage and may

  9. Strategy for an Australian research program into possible health issues associated with exposure to communications radiofrequencies

    International Nuclear Information System (INIS)

    Roy, C.R.; Barnett, S.B.; Lokan, K.H.; Kossoff, G.; Anderson, H.

    1998-01-01

    Telecommunications in Australia has expanded rapidly in recent years. Growth in personal and mobile telecommunications has resulted in the construction of numerous base station antennae. These antennae are highly visible and are often sited in public or high traffic areas. There has also been an increase in the number of mobile phone handsets-the small, low power transmitters held close to the head during use. In the last 2-3 years there has been considerable public concern and media coverage about the possible health effects resulting from exposure to radiofrequency fields or radiofrequency radiation (RFR) which is used for communicating between handsets and base stations. National and international scientific opinion is that at the present time there is no substantiated evidence that exposure to RFR at levels typically found in the community results in adverse health effects but there is a need for further study. Although considerable research has been undertaken on exposure to extremely low frequency (ELF) 50/60 Hz fields, limited information is available on human exposure to RFR in the frequency range 100 kHz to 300 GHz. The frequency bands used for the mobile phone networks are mainly in the 800-900 MHz spectrum region with developing technology using the 1.8-2.2 GHz band. In the digital GSM system pulse modulation occurs at 217 Hz. Radio and television broadcasts are in the 0.3-600 MHz range. Other sources include paging systems, personal communication systems and industrial sources. The discussion paper outlines possible priority areas and makes recommendation for further study under the Australian Research Program

  10. Immune responses of a wall lizard to whole-body exposure to radiofrequency electromagnetic radiation.

    Science.gov (United States)

    Mina, Despoina; Sagonas, Kostas; Fragopoulou, Adamantia F; Pafilis, Panayiotis; Skouroliakou, Aikaterini; Margaritis, Lukas H; Tsitsilonis, Ourania E; Valakos, Efstratios D

    2016-01-01

    During the last three decades, the number of devices that emit non-ionizing electromagnetic radiation (EMR) at the wireless communication spectrum has rapidly increased and possible effects on living organisms have become a major concern. The purpose of this study was to investigate the effects of radiofrequency EMR emitted by a widely used wireless communication device, namely the Digital Enhanced Communication Telephony (DECT) base, on the immune responses of the Aegean wall lizard (Podarcis erhardii). Adult male lizards were exposed 24 h/day for 8 weeks to 1880-1900 MHz DECT base radiation at average electric field intensity of 3.2 V/m. Immune reactivity was assessed using the phytohemagglutinin (PHA) skin swelling and mixed lymphocyte reaction (MLR) tests. Our results revealed a noticeable suppression (approximately 45%) of inflammatory responses in EMR-exposed lizards compared to sham-exposed animals. T cell-mediated responses were marginally affected. Daily radiofrequency EMR exposure seems to affect, at least partially, the immunocompetence of the Aegean wall lizard.

  11. Cytogenetic Damages Induced by Chronic Exposure to Microwave Non-Ionizing Radiofrequency Fields

    Directory of Open Access Journals (Sweden)

    Boris Đinđić

    2013-12-01

    Full Text Available Non-ionizing radiation has a significant and positive impact on modern society through a number of uses. There is increasing public concern regarding the health risks of radio-frequency (RF radiation, particularly that produced by mobile phones. Concern regarding the potential risks of exposure to EMFs has led to many epidemiological investigations, but the effects of EMF exposure on human and other mammalian cells are still unclear. One of the most frequently asked questions about the effects of microwave radiation on biological systems is whether they produce genotoxic effects and could be there a possible link with oncogenic processes. It is most difficult to get accurate and reproducible results for the studies that tell us most about the effects of EMF on humans. Based on some “weak” evidence suggesting an association between exposure to radiofrequency fields (RF emitted from mobile phones and two types of brain cancer, glioma and acoustic neuroma, the International Agency for Research on Cancer has classified RF as ‘possibly carcinogenic to humans’ in group 2B. Literature results suggest that pulsed microwaves from working environment can be the cause of genetic and cell alterations. Taken together, the increased frequency of DNA damages, increased intensity of oxydative stress and production of reactive oxygen species as well as prolonged disruption in DNA repair mechanisms could be possible mechanisms for microwave induced cytogenetic damages even at low-level electromagnetic fields. Although there were contradictory results about harmful effects of electromagnetic fields we recommend that the mobile phone should be kept as far as possible from the body during conversations and also during usual daily activities to reduce the absorption of radiation by cells. In addition, the appropriate intake of antioxidant-rich food or drugs may be helpful for preventing the genotoxic effects that could be caused by mobile phone use.

  12. Human brain wave activity during exposure to radiofrequency field emissions from mobile phones

    International Nuclear Information System (INIS)

    D'Costa, H.; Cosic, I.

    2003-01-01

    The aim of this study was to determine whether there is an effect of mobile phone electromagnetic field emissions on the human electroencephalograph (EEG). EEG recordings from ten awake subjects were taken during exposure to radiofrequency (RF) emissions from a mobile phone positioned behind the head. Two experimental trials were conducted. In the first trial, RF exposures were generated by a GSM mobile phone with the speaker disabled and configured to transmit at full-radiated power. During the second trial, exposures were generated by a non-modified GSM mobile phone in active standby mode. For each trial, subjects were exposed in five minute intervals to a randomized, interrupted sequence of five active and five sham exposures. The experiment was conducted under single-blind conditions. The average EEG band power in active exposure recordings was compared to corresponding sham recordings. Statistical tests indicated significant difference in the full-power mode trial within the EEG alpha (8-13 Hz) and beta (13-32 Hz) bands. A subsequent statistical analysis of median spectral power in discrete EEG rhythms revealed significant differences in 7 of the 32 distinct frequencies overall. In conclusion, the results of this study lend support to EEG effects from mobile phones activated in talk-mode. Copyright (2003) Australasian College of Physical Scientists and Engineers in Medicine

  13. Induction of Autophagy in the Striatum and Hypothalamus of Mice after 835 MHz Radiofrequency Exposure

    Science.gov (United States)

    Kim, Hak Rim

    2016-01-01

    The extensive use of wireless mobile phones and associated communication devices has led to increasing public concern about potential biological health-related effects of the exposure to electromagnetic fields (EMFs). EMFs emitted by a mobile phone have been suggested to influence neuronal functions in the brain and affect behavior. However, the affects and phenotype of EMFs exposure are unclear. We applied radiofrequency (RF) of 835 MHz at a specific absorption rate (SAR) of 4.0 W/kg for 5 hours/day for 4 and 12 weeks to clarify the biological effects on mouse brain. Interestingly, microarray data indicated that a variety of autophagic related genes showed fold-change within small range after 835 MHz RF exposure. qRT-PCR revealed significant up-regulation of the autophagic genes Atg5, LC3A and LC3B in the striatum and hypothalamus after a 12-week RF. In parallel, protein expression of LC3B-II was also increased in both brain regions. Autophagosomes were observed in the striatum and hypothalamus of RF-exposed mice, based on neuronal transmission electron microscopy. Taken together, the results indicate that RF exposure of the brain can induce autophagy in neuronal tissues, providing insight into the protective mechanism or adaptation to RF stress. PMID:27073885

  14. Comparison of radiofrequency exposure of a mouse dam and foetuses at 900 MHz

    Energy Technology Data Exchange (ETDEWEB)

    McIntosh, Robert L; Wood, Andrew W [Australian Centre for Radiofrequency Bioeffects Research, Hawthorn, VIC, 3122 (Australia); Deppeler, Lauren; Oliva, Megan; Parente, John; Tambuwala, Faiyaz; Turner, Stephen; Winship, David [Swinburne University of Technology, Hawthorn, VIC, 3122 (Australia)], E-mail: robert.l.mcintosh@team.telstra.com

    2010-02-21

    In vivo studies involving radiofrequency (RF) exposure of rodents require detailed dosimetric analysis to enable correct interpretation of biological outcomes. Detailed anatomical models of mice--a female, a pregnant female, a male and a foetus--have been developed for analyses using finite difference numerical techniques. The mouse models, consisting of 49 tissues, will be made freely available to the research community. In this note, the pregnant mouse model, which included eight mature foetuses, was utilized specifically to consider (a) the RF dosimetry in a radial cavity exposure system operated at a frequency of 900 MHz and (b) a 900 MHz plane wave exposure. A comparison was made between the exposure of the mouse dam and the foetuses as specified by the specific energy absorption rate (SAR) and the resultant temperature change. In general, the SAR levels in the foetuses were determined to be slightly lower (around 14% lower than the average values of the dam) and the peak temperature increase was significantly lower (45%) than the values in the dam. (note)

  15. Mobile phone radiofrequency exposure has no effect on DNA double strand breaks (DSB) in human lymphocytes.

    Science.gov (United States)

    Danese, Elisa; Lippi, Giuseppe; Buonocore, Ruggero; Benati, Marco; Bovo, Chiara; Bonaguri, Chiara; Salvagno, Gian Luca; Brocco, Giorgio; Roggenbuck, Dirk; Montagnana, Martina

    2017-07-01

    The use of mobile phones has been associated with an increased risk of developing certain type of cancer, especially in long term users. Therefore, this study was aimed to investigate the potential genotoxic effect of mobile phone radiofrequency exposure on human peripheral blood mononuclear cells in vitro. The study population consisted in 14 healthy volunteers. After collection of two whole blood samples, the former was placed in a plastic rack, 1 cm from the chassis of a commercial mobile phone (900 MHz carrier frequency), which was activated by a 30-min call. The second blood sample was instead maintained far from mobile phones or other RF sources. The influence of mobile phone RF on DNA integrity was assessed by analyzing γ-H2AX foci in lymphocytes using immunofluorescence staining kit on AKLIDES. No measure of γ-H2AX foci was significantly influenced by mobile phone RF exposure, nor mobile phone exposure was associated with significant risk of genetic damages in vitro (odds ratio comprised between 0.27 and 1.00). The results of this experimental study demonstrate that exposure of human lymphocytes to a conventional 900 MHz RF emitted by a commercial mobile phone for 30 min does not significantly impact DNA integrity.

  16. Exposure to Radiofrequency Electromagnetic Fields and Sleep Quality: A Prospective Cohort Study

    Science.gov (United States)

    Mohler, Evelyn; Frei, Patrizia; Fröhlich, Jürg; Braun-Fahrländer, Charlotte; Röösli, Martin

    2012-01-01

    Background There is persistent public concern about sleep disturbances due to radiofrequency electromagnetic field (RF-EMF) exposure. The aim of this prospective cohort study was to investigate whether sleep quality is affected by mobile phone use or by other RF-EMF sources in the everyday environment. Methods We conducted a prospective cohort study with 955 study participants aged between 30 and 60 years. Sleep quality and daytime sleepiness was assessed by means of standardized questionnaires in May 2008 (baseline) and May 2009 (follow-up). We also asked about mobile and cordless phone use and asked study participants for consent to obtain their mobile phone connection data from the mobile phone operators. Exposure to environmental RF-EMF was computed for each study participant using a previously developed and validated prediction model. In a nested sample of 119 study participants, RF-EMF exposure was measured in the bedroom and data on sleep behavior was collected by means of actigraphy during two weeks. Data were analyzed using multivariable regression models adjusted for relevant confounders. Results In the longitudinal analyses neither operator-recorded nor self-reported mobile phone use was associated with sleep disturbances or daytime sleepiness. Also, exposure to environmental RF-EMF did not affect self-reported sleep quality. The results from the longitudinal analyses were confirmed in the nested sleep study with objectively recorded exposure and measured sleep behavior data. Conclusions We did not find evidence for adverse effects on sleep quality from RF-EMF exposure in our everyday environment. PMID:22624036

  17. Radiofrequency electromagnetic radiation exposure inside the metro tube infrastructure in Warszawa.

    Science.gov (United States)

    Gryz, Krzysztof; Karpowicz, Jolanta

    2015-09-01

    Antennas from various wireless communications systems [e.g. mobile phones base transceiver stations (BTS) and handsets used by passengers, public Internet access, staff radiophone transmitters used between engine-drivers and traffic operators] emitting radiofrequency electromagnetic radiation (RF-EMR) are used inside underground metro public transportation. Frequency-selective exposimetric investigations of RF-EMR exposure inside the metro infrastructure in Warsaw (inside metro cars passing between stations and on platforms) were performed. The statistical parameters of exposure to the E-field were analyzed for each frequency range and for a total value (representing the wide-band result of measurements of complex exposure). The recorded exposimetric profiles showed the dominant RF-EMR sources: handsets and BTS of mobile communication systems (GSM 900 and UMTS 2100) and local wireless Internet access (WiFi 2G). Investigations showed that the GSM 900 system is the dominant source of exposure - BTS (incessantly active) on platforms, and handsets - used by passengers present nearby during the tube drive. The recorded E-field varies between sources (for BTS were: medians - 0.22 V/m and 75th percentile - 0.37 V/m; and for handsets: medians - 0.28 V/m and 75th percentile - 0.47 V/m). Maximum levels (peaks) of exposure recorded from mobile handsets exceeded 10 V/m (upper limit of used exposimeters). Broadband measurements of E-field, including the dominant signal emitted by staff radiophones (151 MHz), showed that the level of this exposure of engine-drivers does not exceed 2.5 V/m.

  18. Exposure to radiofrequency electromagnetic fields and sleep quality: a prospective cohort study.

    Directory of Open Access Journals (Sweden)

    Evelyn Mohler

    Full Text Available BACKGROUND: There is persistent public concern about sleep disturbances due to radiofrequency electromagnetic field (RF-EMF exposure. The aim of this prospective cohort study was to investigate whether sleep quality is affected by mobile phone use or by other RF-EMF sources in the everyday environment. METHODS: We conducted a prospective cohort study with 955 study participants aged between 30 and 60 years. Sleep quality and daytime sleepiness was assessed by means of standardized questionnaires in May 2008 (baseline and May 2009 (follow-up. We also asked about mobile and cordless phone use and asked study participants for consent to obtain their mobile phone connection data from the mobile phone operators. Exposure to environmental RF-EMF was computed for each study participant using a previously developed and validated prediction model. In a nested sample of 119 study participants, RF-EMF exposure was measured in the bedroom and data on sleep behavior was collected by means of actigraphy during two weeks. Data were analyzed using multivariable regression models adjusted for relevant confounders. RESULTS: In the longitudinal analyses neither operator-recorded nor self-reported mobile phone use was associated with sleep disturbances or daytime sleepiness. Also, exposure to environmental RF-EMF did not affect self-reported sleep quality. The results from the longitudinal analyses were confirmed in the nested sleep study with objectively recorded exposure and measured sleep behavior data. CONCLUSIONS: We did not find evidence for adverse effects on sleep quality from RF-EMF exposure in our everyday environment.

  19. Radiofrequency (microwave) radiation exposure of mammalian cells during UV-induced DNA repair synthesis

    International Nuclear Information System (INIS)

    Meltz, M.L.; Walker, K.A.; Erwin, D.N.

    1987-01-01

    The effect of continuous-wave (CW) and pulsed-wave (PW) radiofrequency radiation (RFR) in the microwave range on UV-induced DNA repair has been investigated in MRC-5 normal human diploid fibroblasts. RFR exposure at power densities of 1 (or 5) and 10 mW/cm2 gave a maximum specific absorption rate (SAR) (at 10 mW/cm2) of 0.39 +/- 0.15 W/kg for 350 MHz RFR, 4.5 +/- 3.0 W/kg for 850 MHz RFR, and 2.7 +/- 1.6 W/kg for 1.2 GHz RFR. RFR exposures for 1 to 3 h at 37 degrees C, in either continuous-wave or pulsed-wave modes, had no effect on the rate of repair replication label incorporated into preexisting UV-damaged DNA. RFR exposures (PW), with a constant medium temperature of 39 degrees C at 350 and 850 MHz during the repair period after UV damage, also had no effect. Assay for induction of repair synthesis by RFR exposure alone in non-UV irradiated cells was negative for the 350-, 850-, and 1200-MHz CW and PW RFR at 37 degrees C and the 350- and 850-MHz PW RFR at 39 degrees C. RFR does not induce DNA repair under these exposure conditions. In preliminary experiments--with the tissue culture medium maintained at 39 degrees C and RFR exposures (PW) at the frequencies of 350, 850, and 1200 MHz--no effect on incorporation of [ 3 H]thymidine into DNA undergoing semiconservative synthesis was observed

  20. Radiofrequency (microwave) radiation exposure of mammalian cells during UV-induced DNA repair synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Meltz, M.L.; Walker, K.A.; Erwin, D.N.

    1987-05-01

    The effect of continuous-wave (CW) and pulsed-wave (PW) radiofrequency radiation (RFR) in the microwave range on UV-induced DNA repair has been investigated in MRC-5 normal human diploid fibroblasts. RFR exposure at power densities of 1 (or 5) and 10 mW/cm2 gave a maximum specific absorption rate (SAR) (at 10 mW/cm2) of 0.39 +/- 0.15 W/kg for 350 MHz RFR, 4.5 +/- 3.0 W/kg for 850 MHz RFR, and 2.7 +/- 1.6 W/kg for 1.2 GHz RFR. RFR exposures for 1 to 3 h at 37 degrees C, in either continuous-wave or pulsed-wave modes, had no effect on the rate of repair replication label incorporated into preexisting UV-damaged DNA. RFR exposures (PW), with a constant medium temperature of 39 degrees C at 350 and 850 MHz during the repair period after UV damage, also had no effect. Assay for induction of repair synthesis by RFR exposure alone in non-UV irradiated cells was negative for the 350-, 850-, and 1200-MHz CW and PW RFR at 37 degrees C and the 350- and 850-MHz PW RFR at 39 degrees C. RFR does not induce DNA repair under these exposure conditions. In preliminary experiments--with the tissue culture medium maintained at 39 degrees C and RFR exposures (PW) at the frequencies of 350, 850, and 1200 MHz--no effect on incorporation of (/sup 3/H)thymidine into DNA undergoing semiconservative synthesis was observed.

  1. Male reproductive health under threat: Short term exposure to radiofrequency radiations emitted by common mobile jammers

    Directory of Open Access Journals (Sweden)

    SMJ Mortazavi

    2013-01-01

    Full Text Available Background: Modern life prompted man to increasingly generate, transmit and use electricity that leads to exposure to different levels of electromagnetic fields (EMFs. Substantial evidence indicates that exposure to common sources of EMF such as mobile phones, laptops or wireless internet-connected laptops decreases human semen quality. In some countries, mobile jammers are occasionally used in offices, shrines, conference rooms and cinemas to block the signal. Aims: To the best of our knowledge, this is the first study to investigate the effect of short term exposure of human sperm samples to radiofrequency (RF radiations emitted by common mobile jammers. Subjects and Methods: Fresh semen samples were collected by masturbation from 30 healthy donors who had referred to Infertility Treatment Center at the Mother and Child Hospital with their wives. Female problem was diagnosed as the reason for infertility in these couples. Statistical Analysis: T-test and analysis of variance were used to show statistical significance. Results: The motility of sperm samples exposed to jammer RF radiation for 2 or 4 h were significantly lower than those of sham-exposed samples. These findings lead us to the conclusion that mobile jammers may significantly decrease sperm motility and the couples′ chances of conception. Conclusion: Based on these results, it can be suggested that in countries that have not banned mobile jammer use, legislations should be urgently passed to restrict the use of these signal blocking devices in public or private places.

  2. Diverse radiofrequency sensitivity and radiofrequency effects of mobile or cordless phone near fields exposure in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Styliani Geronikolou

    Full Text Available INTRODUCTION: The impact of electromagnetic fields on health is of increasing scientific interest. The aim of this study was to examine how the Drosophila melanogaster animal model is affected when exposed to portable or mobile phone fields. METHODS/RESULTS: Two experiments have been designed and performed in the same laboratory conditions. Insect cultures were exposed to the near field of a 2G mobile phone (the GSM 2G networks support and complement in parallel the 3G wide band or in other words the transmission of information via voice signals is served by the 2G technology in both mobile phones generations and a 1880 MHz cordless phone both digitally modulated by human voice. Comparison with advanced statistics of the egg laying of the second generation exposed and non-exposed cultures showed limited statistical significance for the cordless phone exposed culture and statistical significance for the 900 MHz exposed insects. We calculated by physics, simulated and illustrated in three dimensional figures the calculated near fields of radiation inside the experimenting vials and their difference. Comparison of the power of the two fields showed that the difference between them becomes null when the experimental cylinder radius and the height of the antenna increase. CONCLUSIONS/SIGNIFICANCE: Our results suggest a possible radiofrequency sensitivity difference in insects which may be due to the distance from the antenna or to unexplored intimate factors. Comparing the near fields of the two frequencies bands, we see similar not identical geometry in length and height from the antenna and that lower frequencies tend to drive to increased radiofrequency effects.

  3. Does exposure to environmental radiofrequency electromagnetic fields cause cognitive and behavioral effects in 10-year-old boys?

    Science.gov (United States)

    Calvente, Irene; Pérez-Lobato, Rocío; Núñez, María-Isabel; Ramos, Rosa; Guxens, Mònica; Villalba, Juan; Olea, Nicolás; Fernández, Mariana F

    2016-01-01

    The relationship between exposure to electromagnetic fields from non-ionizing radiation and adverse human health effects remains controversial. We aimed to explore the association of environmental radiofrequency-electromagnetic fields (RF-EMFs) exposure with neurobehavioral function of children. A subsample of 123 boys belonging to the Environment and Childhood cohort from Granada (Spain), recruited at birth from 2000 through 2002, were evaluated at the age of 9-11 years. Spot electric field measurements within the 100 kHz to 6 GHz frequency range, expressed as both root mean-square (S(RMS) and maximum power density (S(MAX)) magnitudes, were performed in the immediate surrounds of childreńs dwellings. Neurocognitive and behavioral functions were assessed with a comprehensive battery of tests. Multivariate linear and logistic regression models were used, adjusting for potential confounders. All measurements were lower than reference guideline limits, with median S(RMS) and S(MAX) values of 285.94 and 2759.68 μW/m(2), respectively. Most of the cognitive and behavioral parameters did not show any effect, but children living in higher RF exposure areas (above median S(RMS) levels) had lower scores for verbal expression/comprehension and higher scores for internalizing and total problems, and obsessive-compulsive and post-traumatic stress disorders, in comparison to those living in areas with lower exposure. These associations were stronger when S(MAX) values were considered. Although some of our results may suggest that low-level environmental RF-EMF exposure has a negative impact on cognitive and/or behavior development in children; given limitations in the study design and that the majority of neurobehavioral functioning tasks were not affected, definitive conclusions cannot be drawn. © 2015 Wiley Periodicals, Inc.

  4. Radiofrequency exposure in young and old: different sensitivities in light of age-relevant natural differences.

    Science.gov (United States)

    Redmayne, Mary; Johansson, Olle

    2015-01-01

    Our environment is now permeated by anthropogenic radiofrequency electromagnetic radiation, and individuals of all ages are exposed for most of each 24 h period from transmitting devices. Despite claims that children are more likely to be vulnerable than healthy adults to unwanted effects of this exposure, there has been no recent examination of this, nor of comparative risk to the elderly or ill. We sought to clarify whether research supports the claim of increased risk in specific age-groups. First, we identified the literature which has explored age-specific pathophysiological impacts of RF-EMR. Natural life-span changes relevant to these different impacts provides context for our review of the selected literature, followed by discussion of health and well-being implications. We conclude that age-dependent RF-EMR study results, when considered in the context of developmental stage, indicate increased specific vulnerabilities in the young (fetus to adolescent), the elderly, and those with cancer. There appears to be at least one mechanism other than the known thermal mechanism causing different responses to RF-EMR depending upon the exposure parameters, the cell/physiological process involved, and according to age and health status. As well as personal health and quality-of-life impacts, an ageing population means there are economic implications for public health and policy.

  5. Exposure to Radiofrequency Electromagnetic Fields From Wi-Fi in Australian Schools.

    Science.gov (United States)

    Karipidis, Ken; Henderson, Stuart; Wijayasinghe, Don; Tjong, Lydiawati; Tinker, Rick

    2017-08-01

    The increasing use of Wi-Fi in schools and other places has given rise to public concern that the radiofrequency (RF) electromagnetic fields from Wi-Fi have the potential to adversely affect children. The current study measured typical and peak RF levels from Wi-Fi and other sources in 23 schools in Australia. All of the RF measurements were much lower than the reference levels recommended by international guidelines for protection against established health effects. The typical and peak RF levels from Wi-Fi in locations occupied by children in the classroom were of the order of 10-4 and 10-2% of the exposure guidelines, respectively. Typical RF levels in the classroom were similar between Wi-Fi and radio but higher than other sources. In the schoolyard typical RF levels were higher for radio, TV and mobile phone base stations compared to Wi-Fi. The results of this study showed that the typical RF exposure of children from Wi-Fi at school is very low and comparable or lower to other sources in the environment. © The Author 2017. Published by Oxford University Press.

  6. Radio-frequency radiation exposure from AM radio transmitters and childhood leukemia and brain cancer.

    Science.gov (United States)

    Ha, Mina; Im, Hyoungjune; Lee, Mihye; Kim, Hyun Joo; Kim, Byung-Chan; Gimm, Yoon-Myoung; Pack, Jeong-Ki

    2007-08-01

    Leukemia and brain cancer patients under age 15 years, along with controls with respiratory illnesses who were matched to cases on age, sex, and year of diagnosis (1993-1999), were selected from 14 South Korean hospitals using the South Korean Medical Insurance Data System. Diagnoses were confirmed through the South Korean National Cancer Registry. Residential addresses were obtained from medical records. A newly developed prediction program incorporating a geographic information system that was modified by the results of actual measurements was used to estimate radio-frequency radiation (RFR) exposure from 31 amplitude modulation (AM) radio transmitters with a power of 20 kW or more. A total of 1,928 leukemia patients, 956 brain cancer patients, and 3,082 controls were analyzed. Cancer risks were estimated using conditional logistic regression adjusted for residential area, socioeconomic status, and community population density. The odds ratio for all types of leukemia was 2.15 (95% confidence interval (CI): 1.00, 4.67) among children who resided within 2 km of the nearest AM radio transmitter as compared with those resided more than 20 km from it. For total RFR exposure from all transmitters, odds ratios for lymphocytic leukemia were 1.39 (95% CI: 1.04, 1.86) and 1.59 (95% CI: 1.19, 2.11) for children in the second and third quartiles, respectively, versus the lowest quartile. Brain cancer and infantile cancer were not associated with AM RFR.

  7. Paternal occupational exposure to radiofrequency electromagnetic fields and risk of adverse pregnancy outcome

    International Nuclear Information System (INIS)

    Mjoen, Geir; Saetre, Dag Ottar; Lie, Rolv T.; Tynes, Tore; Blaasaas, Karl Gerhard; Hannevik, Merete; Irgens, Lorentz M.

    2006-01-01

    Background:During the last decades, public concern that radiofrequency radiation (RFR) may be related to adverse reproductive outcomes has been emerging. Our objective was to assess associations between paternal occupational exposure to RFR and adverse pregnancy outcomes including birth defects using population-based data from Norway.Methods:Data on reproductive outcomes derived from the Medical Birth Registry of Norway were linked with data on paternal occupation derived from the general population censuses. An expert panel categorized occupations according to exposure. Using logistic regression, we analyzed 24 categories of birth defects as well as other adverse outcomes.Results:In the offspring of fathers most likely to have been exposed, increased risk was observed for preterm birth (odds ratio (OR): 1.08, 95% confidence interval (CI): 1.03, 1.15). In this group we also observed a decreased risk of cleft lip (OR: 0.63, 95% CI: 0.41, 0.97). In the medium exposed group, we observed increased risk for a category of ,other defects' (OR: 2.40, 95% CI: 1.22, 4.70), and a decreased risk for a category of ,other syndromes' (OR: 0.75, 95% CI: 0.56, 0.99) and upper gastrointestinal defects (OR: 0.61, 95% CI: 0.40, 0.93).Conclusion:The study is partly reassuring for occupationally exposed fathers

  8. Exposure to radiofrequency electromagnetic fields from Wi-Fi in Australian schools

    International Nuclear Information System (INIS)

    Karipidis, Ken; Henderson, Stuart; Wijayasinghe, Don; Tjong, Lydiawati; Tinker, Rick

    2017-01-01

    The increasing use of Wi-Fi in schools and other places has given rise to public concern that the radiofrequency (RF) electromagnetic fields from Wi-Fi have the potential to adversely affect children. The current study measured typical and peak RF levels from Wi-Fi and other sources in 23 schools in Australia. All of the RF measurements were much lower than the reference levels recommended by international guidelines for protection against established health effects. The typical and peak RF levels from Wi-Fi in locations occupied by children in the classroom were of the order of 10 4 and 10 2 % of the exposure guidelines, respectively. Typical RF levels in the classroom were similar between Wi-Fi and radio but higher than other sources. In the school yard typical RF levels were higher for radio, TV and mobile phone base stations compared to Wi-Fi. The results of this study showed that the typical RF exposure of children from Wi-Fi at school is very low and comparable or lower to other sources in the environment. (authors)

  9. Health problems among operators of plastic welding machines and exposure to radiofrequency electromagnetic fields.

    Science.gov (United States)

    Kolmodin-Hedman, B; Hansson Mild, K; Hagberg, M; Jönsson, E; Andersson, M C; Eriksson, A

    1988-01-01

    To study possible medical effects of high radiofrequency radiation (RF), 113 Swedish men and women were studied by means of a structured interview and rating of subjective symptoms. A test session was included in order to examine coordination and muscular function of the hands. A neurological test concerning two-point discrimination (2-PD) was also done. As referents, 23 women, sewing machine operators and assembly workers, were chosen, interviewed and likewise tested. Exposure measurements were taken of the RF fields around the welding machines. The present Swedish ceiling value of 250 W/m2 for the equivalent power density was exceeded in more than 50% of the machines. The highest leakage fields, both for electric and magnetic fields, were found near machines used in factories for ready-made clothing, which gave a high exposure to the hands. Irritative eye symptoms were reported by 23% of the men and 40% of the women. A group of 27 persons was selected for a clinical eye examination and checked by photographs, and nine persons had modest conjunctivitis. A high prevalence of numbness in hands, especially among women, was found. A significantly impaired 2-PD was found in the exposed women as compared to the referent group. The pregnancy outcome for 305 female plastic welders during 1974-1984 did not show any significant differences with the Swedish average concerning malformation or prenatal mortality.

  10. Radiofrequency electromagnetic field exposure and non-specific symptoms of ill health: A systematic review

    International Nuclear Information System (INIS)

    Roeoesli, Martin

    2008-01-01

    This article is a systematic review of whether everyday exposure to radiofrequency electromagnetic field (RF-EMF) causes symptoms, and whether some individuals are able to detect low-level RF-EMF (below the ICNIRP [International Commission on Non-Ionizing Radiation Protection] guidelines). Peer-reviewed articles published before August 2007 were identified by means of a systematic literature search. Meta-analytic techniques were used to pool the results from studies investigating the ability to discriminate active from sham RF-EMF exposure. RF-EMF discrimination was investigated in seven studies including a total of 182 self-declared electromagnetic hypersensitive (EHS) individuals and 332 non-EHS individuals. The pooled correct field detection rate was 4.2% better than expected by chance (95% CI: -2.1 to 10.5). There was no evidence that EHS individuals could detect presence or absence of RF-EMF better than other persons. There was little evidence that short-term exposure to a mobile phone or base station causes symptoms based on the results of eight randomized trials investigating 194 EHS and 346 non-EHS individuals in a laboratory. Some of the trials provided evidence for the occurrence of nocebo effects. In population based studies an association between symptoms and exposure to RF-EMF in the everyday environment was repeatedly observed. This review showed that the large majority of individuals who claims to be able to detect low level RF-EMF are not able to do so under double-blind conditions. If such individuals exist, they represent a small minority and have not been identified yet. The available observational studies do not allow differentiating between biophysical from EMF and nocebo effects

  11. Radiofrequency Neurotomy

    Science.gov (United States)

    ... drive you home What you can expect During radiofrequency neurotomy Radiofrequency neurotomy is an outpatient procedure, so ... skin before the radiofrequency needles are inserted. After radiofrequency neurotomy You'll be taken to another room ...

  12. Adaptive Response Induced by Pre-Exposure to 915 MHz Radiofrequency: A Possible Role for Antioxidant Enzyme Activity

    OpenAIRE

    Mortazavi, S.M.J.; Mostafavi-Pour, Z.; Daneshmand, M.; Zal, F.; Zare, R.; Mosleh-Shirazi, M.A.

    2017-01-01

    Background: Over the past few years, the rapid use of high frequency electromagnetic fields like mobile phones has raised global concerns about the negative health effects of its use. Adaptive response is the ability of a cell or tissue to better resist stress damage by prior exposure to a lesser amount of stress. This study aimed to assess whether radiofrequency radiation can induce adaptive response by changing the antioxidant balance. Materials and Methods: In order to assess RF-induced a...

  13. Looking at the other side of the coin: the search for possible biopositive cognitive effects of the exposure to 900 MHz GSM mobile phone radiofrequency radiation.

    Science.gov (United States)

    Mortazavi, Seyed Ali Reza; Tavakkoli-Golpayegani, Ali; Haghani, Masoud; Mortazavi, Seyed Mohammad Javad

    2014-01-01

    Although exposure to electromagnetic radiation in radiofrequency range has caused a great deal of concern globally, radiofrequency radiation has many critical applications in both telecommunication and non-communication fields. The induction of adaptive response phenomena by exposure to radiofrequency radiation as either increased resistance to a subsequent dose of ionizing radiation or resistance to a bacterial infection has been reported recently. Interestingly, the potential beneficial effects of mobile phone radiofrequency radiation are not only limited to the induction of adaptive phenomena. It has previously been indicated that the visual reaction time of university students significantly decreased after a 10 min exposure to radiofrequency radiation emitted by a mobile phone. Furthermore, it has been revealed that occupational exposures to radar radiations decreased the reaction time in radar workers. Based on these findings, it can be hypothesized that in special circumstances, these exposures might lead to a better response of humans to different hazards. Other investigators have also provided evidence that confirms the induction of RF-induced cognitive benefits. Furthermore, some recent reports have indicated that RF radiation may play a role in protecting against cognitive impairment in Alzheimer's disease. In this light, a challenging issue will arise if there are other RF-induced stimulating effects. It is also challenging to explore the potential applications of these effects. Further research may shed light on dark areas of the health effects of short and long-term human exposure to radiofrequency radiation.

  14. Fractionated bipolar radiofrequency and bipolar radiofrequency potentiated by infrared light for treating striae: A prospective randomized, comparative trial with objective evaluation.

    Science.gov (United States)

    Harmelin, Yona; Boineau, Dominique; Cardot-Leccia, Nathalie; Fontas, Eric; Bahadoran, Philippe; Becker, Anne-Lise; Montaudié, Henri; Castela, Emeline; Perrin, Christophe; Lacour, Jean-Philippe; Passeron, Thierry

    2016-03-01

    Very few treatments for striae are based on prospective randomized trials. The objective of this study was to assess the efficacy of bipolar fractional radiofrequency and bipolar radiofrequency potentiated with infrared light, alone or combined, for treating abdominal stretch marks. Bicentric prospective interventional randomized controlled trial in the department of Dermatology of University Hospital of Nice and Aesthetics Laser Center of Bordeaux, France. Men and women of age 18 years or above, who presented for the treatment of mature or immature abdominal striae were included. The patients' abdomens were divided into four equal quadrants. Bipolar radiofrequency potentiated with infrared light and fractional bipolar radiofrequency were applied, alone or combined, and compared to the remaining untreated quadrant. The main criterion of evaluation was the measurement of depth of striae, using 3D photography at 6 months follow-up. A global assessment was also rated by the physician performing the treatment and by the patients. Histological analysis and confocal laser microscopy were additionally performed. A total of 22 patients were enrolled, and 384 striae were measured. In per protocol analysis mean striae depth was decreased by 21.64%, observed at 6 months follow-up with the combined approach, compared to an increase of 1.73% in the control group (P < 0.0001). No significant difference in striae width was observed between the treated or control quadrants. Global assessment by the physician who performed the treatment and by the patient both showed greater improved with the combination treatment compared to control areas (P = 0.004 and P = 0.01, respectively). A more homogeneous interlacing pattern and thicker collagen fibers with a decreased proportion of elastic fibers was observed after treatment. Fractional bipolar radiofrequency, combined with bipolar radiofrequency potentiated by infrared light, is an effective treatment of both immature and

  15. Does exposure to a radiofrequency electromagnetic field modify thermal preference in juvenile rats?

    Directory of Open Access Journals (Sweden)

    Amandine Pelletier

    Full Text Available Some studies have shown that people living near a mobile phone base station may report sleep disturbances and discomfort. Using a rat model, we have previously shown that chronic exposure to a low-intensity radiofrequency electromagnetic field (RF-EMF was associated with paradoxical sleep (PS fragmentation and greater vasomotor tone in the tail. Here, we sought to establish whether sleep disturbances might result from the disturbance of thermoregulatory processes by a RF-EMF. We recorded thermal preference and sleep stage distribution in 18 young male Wistar rats. Nine animals were exposed to a low-intensity RF-EMF (900 MHz, 1 V x m(-1 for five weeks and nine served as non-exposed controls. Thermal preference was assessed in an experimental chamber comprising three interconnected compartments, in which the air temperatures (Ta were set to 24°C, 28°C and 31°C. Sleep and tail skin temperature were also recorded. Our results indicated that relative to control group, exposure to RF-EMF at 31°C was associated with a significantly lower tail skin temperature (-1.6°C which confirmed previous data. During the light period, the exposed group preferred to sleep at Ta = 31°C and the controls preferred Ta = 28°C. The mean sleep duration in exposed group was significantly greater (by 15.5% than in control group (due in turn to a significantly greater amount of slow wave sleep (SWS, +14.6%. Similarly, frequency of SWS was greater in exposed group (by 4.9 episodes.h-1. The PS did not differ significantly between the two groups. During the dark period, there were no significant intergroup differences. We conclude that RF-EMF exposure induced a shift in thermal preference towards higher temperatures. The shift in preferred temperature might result from a cold thermal sensation. The change in sleep stage distribution may involve signals from thermoreceptors in the skin. Modulation of SWS may be a protective adaptation in response to RF-EMF exposure.

  16. Potential health risks due to telecommunications radiofrequency radiation exposures in Lagos State Nigeria.

    Science.gov (United States)

    Aweda, M A; Ajekigbe, A T; Ibitoye, A Z; Evwhierhurhoma, B O; Eletu, O B

    2009-01-01

    The global system mobile telecommunications system (GSM) which was recently introduced in Nigeria is now being used by over 40 million people in Nigeria. The use of GSM is accompanied with exposure of the users to radiofrequency radiation (RFR), which if significant, may produce health hazards. This is the reason why many relevant national and international organizations recommended exposure limits to RFR and why it is made compulsory for GSM handsets to indicate the maximum power output as a guide to potential consumers. This study was conducted to measure the RFR output power densities (S) from the most commonly used GSM handsets used in Lagos State and compare with the limit recommended for safety assessment. Over 1100 most commonly used handsets of different makes and models as well as wireless phones were sampled and studied in all over the local government areas of the State. An RFR meter, Electrosmog from LESSEMF USA was used for the measurements. The handsets were assessed for health risks using the reference value of 9 Wm(-2) as recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The range of the S-values obtained varied from a minimum of 1.294 0.101 Wm(-2) with Siemens model R228 to a maximum of 16.813 +/- 0.094 Wm(-2) with Samsung model C140*. The results from wireless telephones showed very low S-values ranging from a minimum of 0.024 +/- 0.001 Wm(-2) with HUAWEI and ST CDMA 1 to a maximum of 0.093 +/- 0.002 Wm(-2) with HISENSE. The results showed that the population in Lagos State may be at risk due to significant RFR exposures resulting principally from the use of GSM. Quite a number of handsets emit power above the ICNIRP recommended value. Measured RFR power close to Radio and Television masts and transmitters are within tolerable limits in most cases, only that the public should not reside or work close to RFR installations. Phone calls with GSM should be restricted to essential ones while youths and children

  17. Representativeness and repeatability of microenvironmental personal and head exposures to radio-frequency electromagnetic fields.

    Science.gov (United States)

    Thielens, Arno; Van den Bossche, Matthias; Brzozek, Christopher; Bhatt, Chhavi Raj; Abramson, Michael J; Benke, Geza; Martens, Luc; Joseph, Wout

    2018-04-01

    The aims of this study were to: i) investigate the repeatability and representativeness of personal radio frequency-electromagnetic fields (RF-EMFs) exposure measurements, across different microenvironments, ii) perform simultaneous evaluations of personal RF-EMF exposures for the whole body and the head, iii) validate the data obtained with a head-worn personal distributed exposimeter (PDE) against those obtained with an on-body worn personal exposimeter (PEM). Data on personal and head RF-EMF exposures were collected by performing measurements across 15 microenvironments in Melbourne, Australia. A body-worn PEM and a head-worn PDE were used for measuring body and head exposures, respectively. The summary statistics obtained for total RF-EMF exposure showed a high representativeness (r 2 > 0.66 for two paths in the same area) and a high repeatability over time (r 2 > 0.87 for repetitions of the same path). The median head exposure in the 900MHz downlink band ranged between 0.06V/m and 0.31V/m. The results obtained during simultaneous measurements using the two devices showed high correlations (0.42 representativeness and repeatability over time. The personal RF-EMF exposure levels (i.e. body and head exposures) demonstrated moderate to high correlations. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Effect of long-term exposure of 2.4 GHz radiofrequency radiation emitted from Wi-Fi equipment on testes functions.

    Science.gov (United States)

    Dasdag, Suleyman; Taş, Muzaffer; Akdag, Mehmet Zulkuf; Yegin, Korkut

    2015-03-01

    The aim of this study was to investigate long-term effects of radiofrequency radiation (RFR) emitted from a Wireless Fidelity (Wi-Fi) system on testes. The study was carried out on 16 Wistar Albino adult male rats by dividing them into two groups such as sham (n: 8) and exposure (n: 8). Rats in the exposure group were exposed to 2.4 GHz RFR radiation for 24 h/d during 12 months (1 year). The same procedure was applied to the rats in the sham control group except the Wi-Fi system was turned off. Immediately after the last exposure, rats were sacrificed and reproductive organs were removed. Motility (%), concentration (×10(6)/mL), tail defects (%), head defects (%) and total morphologic defects (%) of sperms and weight of testes (g), left epididymis (g), prostate (g), seminal vesicles (g) were determined. Seminiferous tubules diameter (μm) and tunica albuginea thickness (μm) were also measured. However, the results were evaluated by using Johnsen's score. Head defects increased in the exposure group (p  0.05). In conclusion, we observed that long-term exposure of 2.4 GHz RF emitted from Wi-Fi (2420 μW/kg, 1 g average) affects some of the reproductive parameters of male rats. We suggest Wi-Fi users to avoid long-term exposure of RF emissions from Wi-Fi equipment.

  19. A Retrospective Evaluation of Subsurface Monopolar Radiofrequency for Lifting of the Face, Neck, and Jawline.

    Science.gov (United States)

    Dendle, Julia; Wu, Douglas C; Fabi, Sabrina G; Melo, Diana; Goldman, Mitchel P

    2016-11-01

    Subsurface monopolar radiofrequency (SMRF) has emerged as a new method for reducing skin laxity via the controlled delivery of thermal energy below the skin using a radiofrequency probe. To evaluate the overall efficacy of the treatment and satisfaction ratings of subjects who underwent a single SMRF treatment to the face, neck, or jawline (or some combination). A retrospective, single-center study was conducted in which data were obtained via subject follow-ups at 90 and 180 days posttreatment. A total of 35 subjects, 6 men and 29 women, underwent a single SMRF treatment. Overall, 77% of subjects reported improvement, and 64% reported satisfaction with the treatment site at Day 180 posttreatment. Subsurface monopolar radiofrequency represents an effective modality to achieve skin tightening of the face, neck, and jawline. The data suggest that there is an energy delivery threshold, above which a higher percentage of subjects report satisfaction. Analysis of treatments parameters suggests an optimal treatment time and tissue temperature that should be achieved to maximize results.

  20. Effects of 2.45 GHz Radiofrequency Radiation Exposures on Normal ...

    African Journals Online (AJOL)

    sickle cell patients. Blood samples were collected for analysis before and after being irradiated with a 2.45 GHz radiofrequency source. The osmotic fragility of the red blood cells, the packed cell volume and percentage haemolysis for irreversibly ...

  1. Quality Matters: Systematic Analysis of Endpoints Related to “Cellular Life” in Vitro Data of Radiofrequency Electromagnetic Field Exposure

    Science.gov (United States)

    Simkó, Myrtill; Remondini, Daniel; Zeni, Olga; Scarfi, Maria Rosaria

    2016-01-01

    Possible hazardous effects of radiofrequency electromagnetic fields (RF-EMF) at low exposure levels are controversially discussed due to inconsistent study findings. Therefore, the main focus of the present study is to detect if any statistical association exists between RF-EMF and cellular responses, considering cell proliferation and apoptosis endpoints separately and with both combined as a group of “cellular life” to increase the statistical power of the analysis. We searched for publications regarding RF-EMF in vitro studies in the PubMed database for the period 1995–2014 and extracted the data to the relevant parameters, such as cell culture type, frequency, exposure duration, SAR, and five exposure-related quality criteria. These parameters were used for an association study with the experimental outcome in terms of the defined endpoints. We identified 104 published articles, from which 483 different experiments were extracted and analyzed. Cellular responses after exposure to RF-EMF were significantly associated to cell lines rather than to primary cells. No other experimental parameter was significantly associated with cellular responses. A highly significant negative association with exposure condition-quality and cellular responses was detected, showing that the more the quality criteria requirements were satisfied, the smaller the number of detected cellular responses. According to our knowledge, this is the first systematic analysis of specific RF-EMF bio-effects in association to exposure quality, highlighting the need for more stringent quality procedures for the exposure conditions. PMID:27420084

  2. International and National Expert Group Evaluations: Biological/Health Effects of Radiofrequency Fields

    Directory of Open Access Journals (Sweden)

    Vijayalaxmi

    2014-09-01

    Full Text Available The escalated use of various wireless communication devices, which emit non-ionizing radiofrequency (RF fields, have raised concerns among the general public regarding the potential adverse effects on human health. During the last six decades, researchers have used different parameters to investigate the effects of in vitro and in vivo exposures of animals and humans or their cells to RF fields. Data reported in peer-reviewed scientific publications were contradictory: some indicated effects while others did not. International organizations have considered all of these data as well as the observations reported in human epidemiological investigations to set-up the guidelines or standards (based on the quality of published studies and the “weight of scientific evidence” approach for RF exposures in occupationally exposed individuals and the general public. Scientists with relevant expertise in various countries have also considered the published data to provide the required scientific information for policy-makers to develop and disseminate authoritative health information to the general public regarding RF exposures. This paper is a compilation of the conclusions, on the biological effects of RF exposures, from various national and international expert groups, based on their analyses. In general, the expert groups suggested a reduction in exposure levels, precautionary approach, and further research.

  3. Exposure to Radiofrequency Radiation Emitted from Common Mobile Phone Jammers Alters the Pattern of Muscle Contractions: an Animal Model Study.

    Science.gov (United States)

    Rafati, A; Rahimi, S; Talebi, A; Soleimani, A; Haghani, M; Mortazavi, S M J

    2015-09-01

    The rapid growth of wireless communication technologies has caused public concerns regarding the biological effects of electromagnetic radiations on human health. Some early reports indicated a wide variety of non-thermal effects of electromagnetic radiation on amphibians such as the alterations of the pattern of muscle extractions. This study is aimed at investigating the effects of exposure to radiofrequency (RF) radiation emitted from mobile phone jammers on the pulse height of contractions, the time interval between two subsequent contractions and the latency period of frog's isolated gastrocnemius muscle after stimulation with single square pulses of 1V (1 Hz). Frogs were kept in plastic containers in a room. Animals in the jammer group were exposed to radiofrequency (RF) radiation emitted from a common Jammer at a distance of 1m from the jammer's antenna for 2 hours while the control frogs were only sham exposed. Then animals were sacrificed and isolated gastrocnemius muscles were exposed to on/off jammer radiation for 3 subsequent 10 minute intervals. Isolated gastrocnemius muscles were attached to the force transducer with a string. Using a PowerLab device (26-T), the pattern of muscular contractions was monitored after applying single square pulses of 1V (1 Hz) as stimuli. The findings of this study showed that the pulse height of muscle contractions could not be affected by the exposure to electromagnetic fields. However, the latency period was effectively altered in RF-exposed samples. However, none of the experiments could show an alteration in the time interval between two subsequent contractions after exposure to electromagnetic fields. These findings support early reports which indicated a wide variety of non-thermal effects of electromagnetic radiation on amphibians including the effects on the pattern of muscle extractions.

  4. Exposure to Radiofrequency Radiation Emitted from Common Mobile Phone Jammers Alters the Pattern of Muscle Contractions: an Animal Model Study

    Directory of Open Access Journals (Sweden)

    Rafati A.

    2015-09-01

    Full Text Available Introduction: The rapid growth of wireless communication technologies has caused public concerns regarding the biological effects of electromagnetic radiations on human health. Some early reports indicated a wide variety of non-thermal effects of electromagnetic radiation on amphibians such as the alterations of the pattern of muscle extractions. This study is aimed at investigating the effects of exposure to radiofrequency (RF radiation emitted from mobile phone jammers on the pulse height of contractions, the time interval between two subsequent contractions and the latency period of frog’s isolated gastrocnemius muscle after stimulation with single square pulses of 1V (1 Hz. Materials and Methods: Frogs were kept in plastic containers in a room. Animals in the jammer group were exposed to radiofrequency (RF radiation emitted from a common Jammer at a distance of 1m from the jammer’s antenna for 2 hours while the control frogs were only sham exposed. Then animals were sacrificed and isolated gastrocnemius muscles were exposed to on/off jammer radiation for 3 subsequent 10 minute intervals. Isolated gastrocnemius muscles were attached to the force transducer with a string. Using a PowerLab device (26-T, the pattern of muscular contractions was monitored after applying single square pulses of 1V (1 Hz as stimuli. Results: The findings of this study showed that the pulse height of muscle contractions could not be affected by the exposure to electromagnetic fields. However, the latency period was effectively altered in RF-exposed samples. However, none of the experiments could show an alteration in the time interval between two subsequent contractions after exposure to electromagnetic fields. Conclusion: These findings support early reports which indicated a wide variety of non-thermal effects of electromagnetic radiation on amphibians including the effects on the pattern of muscle extractions.

  5. Radio-frequency electromagnetic field (RF-EMF) exposure levels in different European outdoor urban environments in comparison with regulatory limits

    NARCIS (Netherlands)

    Urbinello, Damiano; Joseph, Wout; Huss, Anke; Verloock, Leen; Beekhuizen, Johan; Vermeulen, Roel; Martens, Luc; Röösli, Martin

    Background: Concerns of the general public about potential adverse health effects caused by radio-frequency electromagnetic fields (RF-EMFs) led authorities to introduce precautionary exposure limits, which vary considerably between regions. It may be speculated that precautionary limits affect the

  6. Behavior and memory evaluation of Wistar rats exposed to 1·8 GHz radiofrequency electromagnetic radiation.

    Science.gov (United States)

    Júnior, Luiz Carlos de Caires; Guimarães, Ernesto da Silveira Goulart; Musso, Camila Manso; Stabler, Collin Turner; Garcia, Raúl Marcel González; Mourão-Júnior, Carlos Alberto; Andreazzi, Ana Eliza

    2014-09-01

    The development of communication systems has brought great social and economic benefits to society. As mobile phone use has become widespread, concerns have emerged regarding the potential adverse effects of radiofrequency electromagnetic radiation (RF-EMR) used by these devices. To verify potential effects of mobile phone radiation on the central nervous system (CNS) in an animal model. Male Wistar rats (60 days old) were exposed to RF-EMR from a Global System for Mobile (GSM) cell phone (1·8 GHz) for 3 days. At the end of the exposure, the following behavioral tests were performed: open field and object recognition. Our results showed that exposed animals did not present anxiety patterns or working memory impairment, but stress behavior actions were observed. Given the results of the present study, we speculate that RF-EMR does not promote CNS impairment, but suggest that it may lead to stressful behavioral patterns.

  7. Analysis of public perception of increased radiofrequency exposure from mobile phone in Southwestern Nigeria

    International Nuclear Information System (INIS)

    Oladapo, O.O.; Ishola, G.A.; Ayokunnnu, D.O.

    2011-01-01

    Wireless communication devices have been increasingly used recently in Nigeria with a corresponding public perception of increase in radiofrequency (RF) radiation. This perception has developed into public concerns, thus requiring verification. For the purpose of verification, a survey in form of an opinion poll was conducted by means of an interview using questionnaires. The survey shows that people actually experienced symptoms like headache, fatigue, dizziness, and heat sensation. However, out of the respondents that have experienced one symptoms or the other, 84% still believe it is safe to use mobile phones. Only 4 % of those that claimed they experienced symptoms had consulted a doctor in connection with the symptoms.

  8. Radiofrequency ablation of osteoid osteoma

    NARCIS (Netherlands)

    Vanderschueren, Geert Maria Joris Michael

    2009-01-01

    The main purpose of this thesis was to evaluate the effectiveness and safety of CT-guided radiofrequency ablation for the treatment of spinal and non-spinal osteoid osteomas. Furthermore, the technical requirements needed for safe radiofrequency ablation and the clinical outcome after radiofrequency

  9. Prospective, pilot evaluation of the performance of nanofractional radiofrequency for improvement of skin texture via skin resurfacing.

    Science.gov (United States)

    Bohnert, Krista; Dorizas, Andrew; Sadick, Neil

    2018-02-01

    The latest generation of radiofrequency, nanofractional radiofrequency, allows the heat energy to be delivered through the use of pins or needles as electrodes, facilitating increased efficacy and reduced pain, downtime, and side effects. The objective of this prospective pilot clinical study was to evaluate the efficacy of nanofractional radiofrequency in skin resurfacing. Seventeen subjects were enrolled in the study, and each received three nanofractional radiofrequency (160-pin tip) treatments in the facial area at 3-week intervals. Follow-up visits were scheduled at 1 and 2 months after the final treatment. Clinical photography, patient, and investigator assessments were conducted during the treatment visits and follow-up. All subjects completed the study. At the 1- and 2-month follow-up, there was a moderate to significant improvement (2.6 and 3.5, respectively, P = .01) according to the investigator global esthetic improvement scale rating. Most subjects reported that they were satisfied or very satisfied with the outcome and level of comfort. Nanofractional radiofrequency is a safe and effective strategy for improving texture, tone, and skin laxity with high patient satisfaction and tolerable safety profile. © 2017 Wiley Periodicals, Inc.

  10. Evaluation of the safety and efficacy of percutaneous radiofrequency ablation for treating multiple breast fibroadenoma.

    Science.gov (United States)

    Li, Ping; Xiao-Yin, Tang; Cui, Dan; Chi, Jia-Chang; Wang, Zhi; Wang, Tao; Qi, Xing-Xing; Zhai, Bo

    2016-12-01

    This study was conducted to evaluate the safety and efficacy of ultrasound (US)-guided percutaneous radiofrequency ablation (RFA) for multiple breast fibroadenoma as an alternative to surgical resection. Sixty-five patients with multiple breast fibroadenoma accepted general anesthesia and US-guided percutaneous RFA in our hospital from September 2014 to January 2016. Contrast-enhanced US (CEUS) was used immediately after operation to determine whether the tumor was ablated completely. The complete ablation rate (CAR) and the change of focal volume were evaluated by CEUS at the 1st month and the 3rd month after operation. All the patients were diagnosed by needle biopsy. Among all the patients, 256 nodules were found. Forty-six nodules (17.96%) were located fibroadenoma.

  11. Exposure to low level GSM 935 MHz radiofrequency fields does not induce apoptosis in proliferating or differentiated murine neuroblastoma cells

    International Nuclear Information System (INIS)

    Moquet, J.; Ainsbury, E.; Bouffler, S.; Lloyd, D.

    2008-01-01

    The aim of this study was to investigate whether radiofrequency (RF) fields characteristic of mobile phones at non-thermal levels can induce apoptosis in murine neuroblastoma (N2a) cells in both proliferating and differentiated states. Cells were exposed continuously for 24 h to one of the three 935-MHz RF signals: global system for mobile communication (GSM) basic, GSM talk and a continuous wave, unmodulated signal; all at a specific energy absorption rate of 2 W kg -1 . The measured increase in temperature of the cells due to the RF fields was around 0.06 deg. C. At a number of time points between 0 and 48 h post-exposure, the cells were assessed for apoptosis under a fluorescence microscope using three independent assays: Annexin V, caspase activation and in situ end-labelling. No statistically significant differences in apoptosis levels were observed between the exposed and sham-exposed cells using the three assays at any time point post-exposure. These data suggest that RF exposures, characteristic of GSM mobile phones, do not significantly affect the apoptosis levels in proliferating and differentiated murine neuroblastoma cell line N2a. (authors)

  12. Does Occupational Exposure of Shahid Dastghieb International Airport Workers to Radiofrequency Radiation Affect Their Short Term Memory and Reaction Time?

    Directory of Open Access Journals (Sweden)

    Jarideh S.

    2015-05-01

    Full Text Available Background: Airport workers are continuously exposed to different levels of radiofrequency microwave (RF/MW radiation emitted by radar equipments. Radars are extensively used in military and aviation industries. Over the past several years, our lab has focused on the health effects of exposure to different sources of electromagnetic fields such as cellular phones, mobile base stations, mobile phone jammers, laptop computers, radars, dentistry cavitrons and MRI. The main goal of this study was to investigate if occupational exposure of Shahid Dastghieb international airport workers to radiofrequency radiation affects their short term memory and reaction time. Methods: Thirty two airport workers involved in duties at control and approach tower (21 males and 11 females, with the age range of 27-67 years old (mean age of 37.38, participated voluntary in this study. On the other hand, 29 workers (13 males, and 16 females whose offices were in the city with no exposure history to radar systems were also participated in this study as the control group. The employees’ reaction time and short term memory were analyzed using a standard visual reaction time (VRT test software and the modified Wechsler memory scale test, respectively. Results: The mean± SD values for the reaction times of the airport employees (N=32 and the control group (N=29 were 0.45±0.12 sec and 0.46±0.17 sec, respectively. Moreover, in the four subset tests; i.e. paired words, forward digit span, backward digit span and word recognition, the following points were obtained for the airport employees and the control group, respectively: (i pair words test: 28.00±13.13 and 32.07±11.65, (ii forward digit span: 8.38±1.40 and 9.03±1.32, (iii backward digit span: 5.54±1.87 and 6.31±1.46, and (iv word recognition: 5.73±2.36 and 6.50±1.93. These differences were not statistically significant. Conclusion: The occupational exposure of the employees to the RF radiation in Shahid

  13. The protective effect of autophagy on mouse spermatocyte derived cells exposure to 1800MHz radiofrequency electromagnetic radiation.

    Science.gov (United States)

    Liu, Kaijun; Zhang, Guowei; Wang, Zhi; Liu, Yong; Dong, Jianyun; Dong, Xiaomei; Liu, Jinyi; Cao, Jia; Ao, Lin; Zhang, Shaoxiang

    2014-08-04

    The increasing exposure to radiofrequency (RF) radiation emitted from mobile phone use has raised public concern regarding the biological effects of RF exposure on the male reproductive system. Autophagy contributes to maintaining intracellular homeostasis under environmental stress. To clarify whether RF exposure could induce autophagy in the spermatocyte, mouse spermatocyte-derived cells (GC-2) were exposed to 1800MHz Global System for Mobile Communication (GSM) signals in GSM-Talk mode at specific absorption rate (SAR) values of 1w/kg, 2w/kg or 4w/kg for 24h, respectively. The results indicated that the expression of LC3-II increased in a dose- and time-dependent manner with RF exposure, and showed a significant change at the SAR value of 4w/kg. The autophagosome formation and the occurrence of autophagy were further confirmed by GFP-LC3 transient transfection assay and transmission electron microscopy (TEM) analysis. Furthermore, the conversion of LC3-I to LC3-II was enhanced by co-treatment with Chloroquine (CQ), indicating autophagic flux could be enhanced by RF exposure. Intracellular ROS levels significantly increased in a dose- and time-dependent manner after cells were exposed to RF. Pretreatment with anti-oxidative NAC obviously decreased the conversion of LC3-I to LC3-II and attenuated the degradation of p62 induced by RF exposure. Meanwhile, phosphorylated extracellular-signal-regulated kinase (ERK) significantly increased after RF exposure at the SAR value of 2w/kg and 4w/kg. Moreover, we observed that RF exposure did not increase the percentage of apoptotic cells, but inhibition of autophagy could increase the percentage of apoptotic cells. These findings suggested that autophagy flux could be enhanced by 1800MHz GSM exposure (4w/kg), which is mediated by ROS generation. Autophagy may play an important role in preventing cells from apoptotic cell death under RF exposure stress. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Effect of Exposure to 900 MHz GSM Mobile Phone Radiofrequency Radiation on Estrogen Receptor Methylation Status in Colon Cells of Male Sprague Dawley Rats

    Directory of Open Access Journals (Sweden)

    Mokarram P.

    2017-03-01

    Full Text Available Background: Over the past several years, the rapidly increasing use of mobile phones has raised global concerns about the biological effects of exposure to radiofrequency (RF radiation. Numerous studies have shown that exposure to electromagnetic fields (EMFs can be associated with effects on the nervous, endocrine, immune, cardiovascular, hematopoietic and ocular systems. In spite of genetic diversity, the onset and progression of cancer can be controlled by epigenetic mechanisms such as gene promoter methylation. There are extensive studies on the epigenetic changes of the tumor suppressor genes as well as the identification of methylation biomarkers in colorectal cancer. Some studies have revealed that genetic changes can be induced by exposure to RF radiation. However, whether or not RF radiation is capable of inducing epigenetic alteration has not been clarified yet. To date, no study has been conducted on the effect of radiation on epigenetic alterations in colorectal cancer (CRC. Several studies have also shown that methylation of estrogen receptor α (ERα, MYOD, MGMT, SFRP2 and P16 play an important role in CRC. It can be hypothesized that RF exposure can be a reason for the high incidence of CRC in Iran. This study aimed to investigate whether epigenetic pattern of ERα is susceptible to RF radiation and if RF radiation can induce radioadaptive response as epigenetic changes after receiving the challenge dose (γ-ray. Material and Method: 40 male Sprague-Dawley rats were divided into 4 equal groups (Group I: exposure to RF radiation of a GSM cell phone for 4 hours and sacrificed after 24 hours; Group II: RF exposure for 4 hours, exposure to Co-60 gamma radiation (3 Gy after 24 hours and sacrificed after 72 hrs; Group III: only 3Gy gamma radiation; Group 4: control group. DNA from colon tissues was extracted to evaluate the methylation status by methylation specific PCR. Results: Our finding showed that exposure to GSM cell phone RF

  15. [Reduction of radiological exposure time during radiofrequency catheter ablation procedures using a novel intracardiac localization system based on the Ohm's law].

    Science.gov (United States)

    Catanzariti, Domenico; Maines, Massimiliano; De Girolamo, Piergiuseppe; Cozzi, Fulvio; Cemin, Claudio; Vergara, Giuseppe

    2004-08-01

    Three-dimensional nonfluoroscopic system may be helpful to guide radiofrequency catheter ablation procedures and to reduce the radiological exposure. A new intracardiac navigation and multicatheter visualization system based on Ohm's law (LocaLisa, Medtronic, Minneapolis, MN, USA) has been recently introduced. The aim of our study was to assess the efficacy of the Loca-Lisa system in comparison to fluoroscopy-based approach in reducing the radiological exposure time required for radiofrequency catheter ablation procedures. One hundred and thirty-seven consecutive patients underwent LocaLisa-based radiofrequency catheter ablation procedures in our cardiac electrophysiology laboratory during 19 months of LocaLisa utilization (from October 2001 to April 2003): 46 atrial flutter, 44 atrioventricular node reentrant tachycardia, 16 atrioventricular reentry tachycardia due to atrioventricular accessory pathway, 14 atrial fibrillation, 11 ectopic atrial tachycardia, and 6 atrioventricular node modulation. We retrospectively compared the radiological exposure times of this group of patients to those of the last 137 patients undergone fluoroscopy-based radiofrequency catheter ablation procedures for curing the same index arrhythmia by the same procedural protocol. The mean radiological exposure time was significantly shorter for the LocaLisa-based radiofrequency catheter ablation procedures (16 +/- 12 vs 34 +/- 17 min; reduction of 53%, p < 0.01) and it occurred for all the arrhythmia types. The reduction was of 64% (from 39 +/- 18 to 14 +/- 12 min, p < 0.01) for atrial flutter, 42% (from 24 +/- 10 to 14 +/- 11 min, p < 0.01) for atrioventricular nodal reentrant tachycardia, 30% (from 40 +/- 14 to 28 +/- 14 min, p = 0.02) for atrioventricular reentry tachycardia, 57% (from 49 +/- 12 to 21 +/- 13 min, p < 0.01) for atrial fibrillation (right atrial linear lesions), 50% (from 38 +/- 12 to 19 +/- 8 min, p < 0.01) for ectopic atrial tachycardia and 42% (from 12 +/- 11 to 7 +/- 5

  16. The prophylactic effect of vitamin C on oxidative stress indexes in rat eyes following exposure to radiofrequency wave generated by a BTS antenna model.

    Science.gov (United States)

    Jelodar, Gholamali; Akbari, Abolfazl; Nazifi, Saeed

    2013-02-01

    This study was conducted to evaluate the effect of radiofrequency wave (RFW)-induced oxidative stress in the eye and the prophylactic effect of vitamin C on this organ by measuring the antioxidant enzymes activity including: glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT), and malondialdehyde (MDA). Thirty-two adult male Sprague-Dawley rats were randomly divided into four experimental groups and treated daily for 45 days as follows: Control, vitamin C (L-ascorbic acid 200 mg/kg of body weight/day by gavage), test (exposed to 900 MHz RFW) and the treated group (received vitamin C in addition to exposure to RFW). At the end of the experiment all animals were sacrificed, their eyes were removed and were used for measurement of antioxidant enzymes and MDA activity. The results indicate that exposure to RFW in the test group decreased antioxidant enzymes activity and increased MDA compared with the control groups (P < 0.05). In the treated group vitamin C improved antioxidant enzymes activity and reduced MDA compared to the test group (P < 0.05). It can be concluded that RFW causes oxidative stress in the eyes and vitamin C improves the antioxidant enzymes activity and decreases MDA.

  17. Radiofrequency radiation

    International Nuclear Information System (INIS)

    Elder, J.A.; Czerski, P.A.; Stuchly, M.A.; Mild, K.H.; Sheppard, A.R.

    1989-01-01

    High-level radiofrequency radiation is a source of thermal energy that carries all of the known implications of heating for biological systems, including burns, temporary and permanent changes in reproduction, cataracts, and death. In general, no changes in chromosomes, DNA or the reproductive potential of animals exposed to RF radiation have been reported in the absence of significant rises in temperature, though there are limited data on DNA and chromosomal changes at non-thermal levels. Human data are currently limited and do not provide adequate information about the relationship between prolonged low-level RF radiation exposure and increased mortality or morbidity, including cancer incidence. In epidemiological studies and clinical reports of RF effects in man, the problems of quantification are numerous and include uncertainties about ''dose'', health effects, latent periods, dose-response relationships, and interactions with other physical or chemical agents. 228 refs, 6 figs, 2 tabs

  18. Exposure to 1800 MHz radiofrequency electromagnetic radiation induces oxidative DNA base damage in a mouse spermatocyte-derived cell line.

    Science.gov (United States)

    Liu, Chuan; Duan, Weixia; Xu, Shangcheng; Chen, Chunhai; He, Mindi; Zhang, Lei; Yu, Zhengping; Zhou, Zhou

    2013-03-27

    Whether exposure to radiofrequency electromagnetic radiation (RF-EMR) emitted from mobile phones can induce DNA damage in male germ cells remains unclear. In this study, we conducted a 24h intermittent exposure (5 min on and 10 min off) of a mouse spermatocyte-derived GC-2 cell line to 1800 MHz Global System for Mobile Communication (GSM) signals in GSM-Talk mode at specific absorption rates (SAR) of 1 W/kg, 2 W/kg or 4 W/kg. Subsequently, through the use of formamidopyrimidine DNA glycosylase (FPG) in a modified comet assay, we determined that the extent of DNA migration was significantly increased at a SAR of 4 W/kg. Flow cytometry analysis demonstrated that levels of the DNA adduct 8-oxoguanine (8-oxoG) were also increased at a SAR of 4 W/kg. These increases were concomitant with similar increases in the generation of reactive oxygen species (ROS); these phenomena were mitigated by co-treatment with the antioxidant α-tocopherol. However, no detectable DNA strand breakage was observed by the alkaline comet assay. Taking together, these findings may imply the novel possibility that RF-EMR with insufficient energy for the direct induction of DNA strand breaks may produce genotoxicity through oxidative DNA base damage in male germ cells. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

  19. Exposure to radio-frequency electromagnetic waves alters acetylcholinesterase gene expression, exploratory and motor coordination-linked behaviour in male rats

    Directory of Open Access Journals (Sweden)

    Adejoke Olukayode Obajuluwa

    Full Text Available Humans in modern society are exposed to an ever-increasing number of electromagnetic fields (EMFs and some studies have demonstrated that these waves can alter brain function but the mechanism still remains unclear. Hence, this study sought to investigate the effect of 2.5 Ghz band radio-frequency electromagnetic waves (RF-EMF exposure on cerebral cortex acetylcholinesterase (AChE activity and their mRNA expression level as well as locomotor function and anxiety-linked behaviour in male rats. Animals were divided into four groups namely; group 1 was control (without exposure, group 2–4 were exposed to 2.5 Ghz radiofrequency waves from an installed WI-FI device for a period of 4, 6 and 8 weeks respectively. The results revealed that WiFi exposure caused a significant increase in anxiety level and affect locomotor function. Furthermore, there was a significant decrease in AChE activity with a concomitant increase in AChE mRNA expression level in WiFi exposed rats when compared with control. In conclusions, these data showed that long term exposure to WiFi may lead to adverse effects such as neurodegenerative diseases as observed by a significant alteration on AChE gene expression and some neurobehavioral parameters associated with brain damage. Keywords: Acetylcholinesterase, Radiofrequency, Electromagnetic waves, mRNA, Gene expression

  20. A prospective clinical study to evaluate the safety and performance of wireless localization of nonpalpable breast lesions using radiofrequency identification technology.

    Science.gov (United States)

    Dauphine, Christine; Reicher, Joshua J; Reicher, Murray A; Gondusky, Christina; Khalkhali, Iraj; Kim, Michelle

    2015-06-01

    The purpose of this study was to evaluate the safety and performance of localizing nonpalpable breast lesions using radiofrequency identification technology. Twenty consecutive women requiring preoperative localization of a breast lesion were recruited. Subjects underwent placement of both a hook wire and a radiofrequency identification tag immediately before surgery. The radiofrequency identification tag was the primary method used by the operating surgeon to localize each lesion during excision, with the hook wire serving as backup in case of tag migration or failed localization. Successful localization with removal of the intended lesion was the primary outcome measured. Tag migration and postoperative infection were also noted to assess safety. Twenty patients underwent placement of a radiofrequency identification tag, 12 under ultrasound guidance and eight with stereotactic guidance. In all cases, the radiofrequency identification tag was successfully localized by the reader at the level of the skin before incision, and the intended lesion was removed along with the radiofrequency identification tag. There were no localization failures and no postoperative infections. Tag migration did not occur before incision, but in three cases, occurred as the lesion was being retracted with fingers to make the final cut along the deep surface of the specimen. In this initial clinical study, radiofrequency tags were safe and able to successfully localize nonpalpable breast lesions. Radiofrequency identification technology may represent an alternative method to hook wire localization.

  1. Proteomic analysis of continuous 900-MHz radiofrequency electromagnetic field exposure in testicular tissue: a rat model of human cell phone exposure.

    Science.gov (United States)

    Sepehrimanesh, Masood; Kazemipour, Nasrin; Saeb, Mehdi; Nazifi, Saeed; Davis, Devra Lee

    2017-05-01

    Although cell phones have been used worldwide, some adverse and toxic effects were reported for this communication technology apparatus. To analyze in vivo effects of exposure to radiofrequency-electromagnetic field (RF-EMF) on protein expression in rat testicular proteome, 20 Sprague-Dawley rats were exposed to 900 MHz RF-EMF for 0, 1, 2, or 4 h/day for 30 consecutive days. Protein content of rat testes was separated by high-resolution two-dimensional electrophoresis using immobilized pH gradient (pI 4-7, 7 cm) and 12% acrylamide and identified by MALDI-TOF/TOF-MS. Two protein spots were found differentially overexpressed (P affect signaling pathways in rat testes and spermatogenesis and play a critical role in protein folding and secretion in the endoplasmic reticulum. Our results indicate that exposure to RF-EMF produces increases in testicular proteins in adults that are related to carcinogenic risk and reproductive damage. In light of the widespread practice of men carrying phones in their pockets near their gonads, where exposures can exceed as-tested guidelines, further study of these effects should be a high priority.

  2. Could myelin damage from radiofrequency electromagnetic field exposure help explain the functional impairment electrohypersensitivity? A review of the evidence.

    Science.gov (United States)

    Redmayne, Mary; Johansson, Olle

    2014-01-01

    Myelin provides the electrical insulation for the central and peripheral nervous system and develops rapidly in the first years of life, but continues into mid-life or later. Myelin integrity is vital to healthy nervous system development and functioning. This review outlines the development of myelin through life, and then considers the evidence for an association between myelin integrity and exposure to low-intensity radiofrequency electromagnetic fields (RF-EMFs) typical in the modern world. In RF-EMF peer-reviewed literature examining relevant impacts such as myelin sheath, multiple sclerosis, and other myelin-related diseases, cellular examination was included. There are surprisingly little data available in each area, but considered together a picture begins to emerge in RF-EMF-exposed cases: (1) significant morphological lesions in the myelin sheath of rats; (2) a greater risk of multiple sclerosis in a study subgroup; (3) effects in proteins related to myelin production; and (4) physical symptoms in individuals with functional impairment electrohypersensitivity, many of which are the same as if myelin were affected by RF-EMF exposure, giving rise to symptoms of demyelination. In the latter, there are exceptions; headache is common only in electrohypersensitivity, while ataxia is typical of demyelination but infrequently found in the former group. Overall, evidence from in vivo and in vitro and epidemiological studies suggests an association between RF-EMF exposure and either myelin deterioration or a direct impact on neuronal conduction, which may account for many electrohypersensitivity symptoms. The most vulnerable are likely to be those in utero through to at least mid-teen years, as well as ill and elderly individuals.

  3. Radiofrequency Exposures of Workers on Low-Power FM Radio Transmitters.

    Science.gov (United States)

    Valic, Blaž; Kos, Bor; Gajšek, Peter

    2017-05-01

    Low-power radio transmitters are one of the most common radio frequency sources and the exposure limit values (ELVs) for occupational exposure may be exceeded close to them. Therefore, a detailed analysis and assessment of occupational exposure in their vicinity is presented in the paper. For 20 different exposure scenarios, electric field strength and specific absorption rate (SAR) values were computed to determine whether the action levels (ALs) and ELVs of the European directive 2013/35/EU are exceeded for different 500 W radio transmitters. The results show that the ALs are very conservative for such exposure situations. Even when the ALs are greatly exceeded, the SAR values are not necessarily above the limit. However, in some situations, the ELVs were also exceeded. The local 10 g averaged value of the SAR can be exceeded if the worker is grounded (in direct contact with the steel structure), while the whole body ELVs can be exceeded for exposures at distances of <1 m from the transmitting dipole array antennas. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  4. Biological effects of exposure to non-ionising electromagnetic fields and radiation: III radiofrequency and microwave radiation

    International Nuclear Information System (INIS)

    Saunders, R.D.; Kowalczuk, C.I.; Sienkiewicz, Z.J.

    1991-12-01

    The biological effects of experimental exposure to radiofrequency (RF) and microwave radiation above 100 kHz are reviewed with the intention of providing a summary of effects directly relevant to considerations of the health and safety of exposed people. The biological bases for restricting exposures are also briefly discussed. Studies of the possible effects of electromagnetic field exposure on human populations are described in a separate report. The majority of the biological effects of acute exposure to radiofrequency (RF) and microwave radiation are consistent with responses to induced heating, resulting either from frank rises in tissue or body temperature of about 1 0 C or more, or from responses involved in minimising the total heat load. Most responses have been reported at specific energy absorption rates (SARs) above about 1-2 W kg -1 in different animal species exposed under various environmental conditions. These animal, particularly primate, data indicate the sorts of responses that are likely to occur in humans subject to a sufficient heat load. In addition, most animal and cell culture data indicate that RF and microwave exposure is not mutagenic and so will not result in somatic mutation or in hereditary effects; such exposure is therefore unlikely to initiate cancers. With some exceptions that are described below, restrictions on the acute exposure of humans to RF or microwave radiation should be based on the acute responses to raised body temperature. It seems probable that healthy people can tolerate short-term (minute-hour) rises in body temperature of up to about 1 0 C. This rise is well below the maximum tolerable increase but nevertheless represents a significant thermal load. The evidence suggests that the exposure of resting humans in moderate environments at whole-body SARs of 1 W kg -1 , and up to 4 W kg -1 for short periods, will result in body temperature rises of less than 1 0 C. A restriction of whole-body SAR for healthy people to 0

  5. Biological effects on human health due to radiofrequency/microwave exposure

    DEFF Research Database (Denmark)

    Breckenkamp, Jürgen; Berg, Gabriele; Blettner, Maria

    2003-01-01

    person years). As exposures were defined: dielectric heaters in a plastic manufacturing plant, working with radio devices (professional and amateur), production of wireless communication technologies, radar devices of the Canadian police, radar units used by the military as well as artificially produced...

  6. An assessment of potential health effects from exposure to PAVE PAWS low-level phased-array radiofrequency energy

    National Research Council Canada - National Science Library

    National Research Council (U.S.). Committee to Assess Potential Health Effects from Exposures to PAVE PAWS Low-Level Phased-Array Radiofrequency Energy

    2005-01-01

    .... Air Force Space Command. In 1979, the National Research Council issued two reports to address concerns from Cape Cod residents about the safety and possible health effects of the radiofrequency energy from the radar...

  7. Percutaneous radiofrequency ablation of lung tumors: evaluation of the literature using evidence-based techniques.

    LENUS (Irish Health Repository)

    Chan, Victoria O

    2012-02-01

    PURPOSE: The aim of this study was to evaluate the literature for articles assessing radiofrequency ablation (RFA) for pulmonary malignancy. MATERIALS AND METHODS: The "bottom-up" approach to evidence-based practice was applied by 2 reviewers to the retrieval and appraisal of original research articles published on pulmonary RFA between 2002 and 2009. Primary lung cancer and pulmonary metastases data were analyzed separately. The relationship between the percentage of local recurrence rate and lesion size, patient age, follow-up duration, and time to local recurrence was assessed using Spearman\\'s rank correlation. Discrete time series were used to evaluate time trends. RESULTS: Secondary evidence yielded 1 review of 26 observational studies. Primary evidence yielded 46 studies that seemed suitable for detailed appraisal. A total of 2905 ablations were performed in 1584 patients. Eight studies evaluated primary lung cancers alone, 11 evaluated pulmonary metastases alone, 25 evaluated both, and 2 did not specify the histology. Results revealed trends toward increasing use of conscious sedation over general anesthesia, increasing use of multitined probes, decreasing size of nodule selection, and use of positron emission tomography\\/computed tomography as the optimal follow-up tool. Mean morbidity was 24.6%. The most prevalent side effects included pneumothorax (28.3%), pleural effusions (14.8%), and pain (14.1%). Procedure-related mortality ranged from 0 to 5.6, with an overall procedure-related mortality rate of 0.21%. There were 282 (12.2%) local recurrences occurring at a mean of 13 months. The mean overall survival rate was 59.4%, and the cancer-specific survival rate was 82.6%. CONCLUSIONS: This evidence-based practice review of pulmonary RFA shows it to be a promising treatment for pulmonary malignancy in carefully selected patient populations. Studies with higher levels of evidence, including case-control, prospective nonrandomized and randomized trials

  8. Naltrexone-sensitive analgesia following exposure of mice to 2450-MHz radiofrequency radiation (RFR)

    Energy Technology Data Exchange (ETDEWEB)

    Maillefer, R.H.; Quock, R.M. (Univ. of Illinois, Rockford (United States))

    1991-03-11

    This study was conducted to determine whether exposure to RFR might induce sufficient thermal stress to activate endogenous opioid mechanisms and induce analgesia. Male Swiss Webster mice, 20-25 g, were exposed to 10, 15 or 20 mV/cm{sup 2} RFR in a 2,450-MHz waveguide system for 10 min, then tested in the abdominal constriction paradigm. Specific absorption rates (SAR) were 23.7 W/kg at 10 mW/cm{sup 2}, 34.6 W/kg at 15 mW/cm{sup 2} and 45.5 W/kg at 20 mW/cm{sup 2}. Confinement in the exposure chamber alone did not appreciably alter body temperature but did appear to induce a stress-associated analgesia that was insensitive to the opioid receptor blocker naltrexone. Exposure of confined mice to RFR elevated body temperature and further increased analgesia in SAR-dependent manner. The high-SAR RFR-induced analgesia, but not the hyperthermia, was reduced by naltrexone. These findings suggest that (1) RFR produces SAR-dependent hyperthermia and analgesia and (2) RFR-induced analgesia is mediated by opioid mechanisms while confinement-induced analgesia involves non-opioid mechanisms.

  9. Determination of the exposure to electromagnetic fields arising from radiofrequency identification technology (RFID) application. Final report

    International Nuclear Information System (INIS)

    Schmid, Gernot; Ueberbacher, Richard; Cecil, Stefan; Escorihuela-Navarro, Ana; Sainitzer, David; Weinfurter, Andreas

    2012-01-01

    In the frame of this project the extent of personal exposure against electromagnetic fields caused by various types of RFID equipment has been analyzed based on measurements on selected devices and numerical computations considering practically relevant exposure scenarios. The obtained results were assessed according to the ICNIRP guidelines published in 1998. Moreover, numerical computations were carried out in order to estimate disturbance voltages induced at the input of cardiac pacemakers. All relevant frequency bands used by present RFID devices were considered. With respect to RFID transponders it was shown that they do not cause relevant exposure. Exposure figures caused by typical active RFID transponders can be expected several orders of magnitude below the corresponding basic restrictions according to ICNIRP 1998. For the assessment of exposure caused by RFID reader devices a differentiation of device categories and operating frequencies is necessary. Small reader devices or handheld readers with operating ranges less than approximately 10 cm, e.g., for reading from or writing to electronic passports, tickets, etc., are based on inductive coupling at operating frequencies 13,56 MHz and 120 kHz. From the obtained results it can be concluded that these devices cause exposure well below the ICNIRP 1998 basic restrictions. Similarly, also measurement and computational results for inductively coupled RF access control and identification systems (13,56 MHz) with even higher operating ranges up to approximately 80 cm indicate that exposure above the basic restrictions is not to be expected for such devices under usual conditions in practice. In contrast, the obtained results for inductively coupled LF reading devices with operating ranges up to approximately 80 cm (operating frequency 120-125 kHz) showed that induced current densities in the central nervous tissue above the basic restrictions are possible for particular devices if a person approaches the

  10. Radiofrequency circuit design and performance evaluation for small animal frequency-domain NIR fluorescence optical tomography

    Science.gov (United States)

    Darne, Chinmay; Zhu, Banghe; Lu, Yujie; Tan, I.-Chih; Rasmussen, John; Sevick-Muraca, Eva M.

    2011-02-01

    Herein we report on hardware development and evaluation for frequency-domain photon migration (FDPM) technique that is miniaturized for incorporation into a micro-CT gantry for hybrid CT/NIR/PET imaging. Immunity to endogenous optical properties and enhanced contrast associated with fluorophore lifetime is inherent to the FDPM measurements and enables unique opportunities for quantitative tomography when compared to the time independent (continuous wave) approach. A miniaturized radiofrequency (rf) circuitry has been developed in our laboratory for homodyne FDPM measurements that makes use of a single 100MHz oscillator to simultaneously launch optically modulated excitation light into a small animal as well as to modulate an NIR sensitive image intensifier for collection of fluorescent signals. The use of a single oscillator not only eliminates signal drift that otherwise results from the use of multiple oscillators individually driving both source and detector, but also reduces the circuit footprint for incorporation into the CT gantry. Herein, overall system performance parameters of signal-to-noise ratio, measurement precision, spatial resolution, modulation depth (ac/dc), excitation light rejection, and clinically relevant data acquisition times are presented for mouse phantom data. Image reconstruction of phantom data and integration of circuitry for hybrid CT/NIR/PET imaging is also presented towards the ultimate validation of NIR optical tomography using PET imaging as a "gold-standard" for quantification.

  11. Postnatal development and behavior effects of in-utero exposure of rats to radiofrequency waves emitted from conventional WiFi devices.

    Science.gov (United States)

    Othman, Haifa; Ammari, Mohamed; Rtibi, Kaïs; Bensaid, Noura; Sakly, Mohsen; Abdelmelek, Hafedh

    2017-06-01

    The present work investigated the effects of prenatal exposure to radiofrequency waves of conventional WiFi devices on postnatal development and behavior of rat offspring. Ten Wistar albino pregnant rats were randomly assigned to two groups (n=5). The experimental group was exposed to a 2.45GHz WiFi signal for 2h a day throughout gestation period. Control females were subjected to the same conditions as treated group without applying WiFi radiations. After delivery, the offspring was tested for physical and neurodevelopment during its 17 postnatal days (PND), then for anxiety (PND 28) and motricity (PND 40-43), as well as for cerebral oxidative stress response and cholinesterase activity in brain and serum (PND 28 and 43). Our main results showed that the in-utero WiFi exposure impaired offspring neurodevelopment during the first seventeen postnatal days without altering emotional and motor behavior at adult age. Besides, prenatal WiFi exposure induced cerebral oxidative stress imbalance (increase in malondialdehyde level (MDA) and hydrogen peroxide (H 2 O 2 ) levels and decrease in catalase (CAT) and superoxide dismutase (SOD) activities) at 28 but not 43days old, also the exposure affected acethylcolinesterase activity at both cerebral and seric levels. Thus, the current study revealed that maternal exposure to WiFi radiofrequencies led to various adverse neurological effects in the offspring by affecting neurodevelopment, cerebral stress equilibrium and cholinesterase activity. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Evaluation of the clinical efficacy of fractional radiofrequency microneedle treatment in acne scars and large facial pores.

    Science.gov (United States)

    Cho, Soo Ick; Chung, Bo Young; Choi, Min Gyu; Baek, Ji Hwoon; Cho, Hee Jin; Park, Chun Wook; Lee, Cheol Heon; Kim, Hye One

    2012-07-01

    Fractional technology overcomes the problems of ablative lasers, such as inaccurate depth control and damage to the epidermis. Minimally invasive fractional radiofrequency microneedle devices allow for more-selective heating of the dermis. To evaluate the clinical efficacy of fractional radiofrequency microneedle (ERM) treatment in acne scars and large facial pores. Thirty patients with acne scars and large facial pores were enrolled. Bipolar radiofrequency energy was delivered to the skin through the electrodes of the FRM device. Skin lesions were evaluated according to grade of acne scars, Investigator Global Assessment of large pores, skin surface roughness, transepidermal water loss (TEWL), dermal density, microscopic and composite image, sebum measurement, and questionnaires regarding patient satisfaction. The grade of acne scars and Investigator Global Assessment of large pores improved in more than 70% of all patients. Skin surface roughness, dermal density, and microscopic and composite images also improved, whereas TEWL and sebum measurement did not change. Clinical improvement from FRM treatment appeared to be related to dermal matrix regeneration. FRM treatment may be effective in improving acne scars and facial pores. © 2012 by the American Society for Dermatologic Surgery, Inc. Published by Wiley Periodicals, Inc.

  13. Evaluation of the intraoperative trauma degree and postoperative speech function of low-temperature plasma radiofrequency surgery treatment of children with OSAHS

    OpenAIRE

    He Liu; Liang Ma; Zhong-Wu Sun

    2017-01-01

    Objective: To evaluate the intraoperative trauma degree and postoperative speech function of low-temperature plasma radiofrequency surgery treatment of children with obstructive sleep apnea hypopnea syndrome (OSAHS). Methods: A total of 118 children with OSAHS were divided into the control group (n=59) who received general surgery and the observation group (n=59) who received the low-temperature plasma radiofrequency surgery according to the random number table. Before operatio...

  14. Multicenter Prospective Clinical Series Evaluating Radiofrequency Ablation in the Treatment of Painful Spine Metastases

    International Nuclear Information System (INIS)

    Bagla, Sandeep; Sayed, Dawood; Smirniotopoulos, John; Brower, Jayson; Neal Rutledge, J.; Dick, Bradley; Carlisle, James; Lekht, Ilya; Georgy, Bassem

    2016-01-01

    BackgroundRadiofrequency ablation (RFA) of vertebral body metastases (VBM) has been reported as safe and effective in retrospective studies. This single-arm prospective multicenter clinical study evaluates RFA in the treatment of painful VBM.MethodsFifty patients with VBM were prospectively enrolled during a 13-month period at eight US centers under an IRB-approved study. Percutaneous RFA was performed under imaging guidance with cement augmentation at the discretion of the operator. Pain, disability and quality of life were evaluated at baseline, prior to discharge, days 3, 7, 30 and 90 using the Numerical Pain Rating Scale, Oswestry Disability Index (ODI), the Functional Assessment of Cancer Therapy-General 7 (FACT-G7) and Functional Assessment of Cancer Therapy Quality-of-Life Measurement in Patients with Bone Pain (FACT-BP). Adverse events were monitored throughout this time interval.ResultsTwenty-six male and 24 female patients (mean age 61.0) underwent 69 treatments (30 thoracic and 39 lumbar). Cement augmentation was performed in 96 % of reported levels. Significant improvement in mean scores for pain, disability and cancer-specific health-related quality of life from baseline to all time intervals was seen. NRPS improved from 5.9 to 2.1 (p < 0.0001). ODI improved from 52.9 to 37.0 (p < 0.08). FACT-G7 improved form 10.9 to 16.2 (p = 0.0001). FACT-BP improved from 22.6 to 38.9 (p < 0.001). No complications related to the procedure were reported.ConclusionRFA with cement augmentation safely and effectively reduces pain and disability rapidly, while increasing quality of life in patients suffering from vertebral body metastases.

  15. Multicenter Prospective Clinical Series Evaluating Radiofrequency Ablation in the Treatment of Painful Spine Metastases

    Energy Technology Data Exchange (ETDEWEB)

    Bagla, Sandeep, E-mail: sandeep.bagla@gmail.com [Vascular Institute of Virginia, LLC (United States); Sayed, Dawood [University of Kansas Medical Center (United States); Smirniotopoulos, John [New York Presbyterian Hospital/Weill Cornell Medical Center (United States); Brower, Jayson [Providence Sacred Heart Medical Center and Children’s Hospital (United States); Neal Rutledge, J. [Seton Medical Center (United States); Dick, Bradley [Suburban Hospital (United States); Carlisle, James [St. Mark’s Hospital (United States); Lekht, Ilya [University of Southern California (United States); Georgy, Bassem [San Diego Imaging (United States)

    2016-09-15

    BackgroundRadiofrequency ablation (RFA) of vertebral body metastases (VBM) has been reported as safe and effective in retrospective studies. This single-arm prospective multicenter clinical study evaluates RFA in the treatment of painful VBM.MethodsFifty patients with VBM were prospectively enrolled during a 13-month period at eight US centers under an IRB-approved study. Percutaneous RFA was performed under imaging guidance with cement augmentation at the discretion of the operator. Pain, disability and quality of life were evaluated at baseline, prior to discharge, days 3, 7, 30 and 90 using the Numerical Pain Rating Scale, Oswestry Disability Index (ODI), the Functional Assessment of Cancer Therapy-General 7 (FACT-G7) and Functional Assessment of Cancer Therapy Quality-of-Life Measurement in Patients with Bone Pain (FACT-BP). Adverse events were monitored throughout this time interval.ResultsTwenty-six male and 24 female patients (mean age 61.0) underwent 69 treatments (30 thoracic and 39 lumbar). Cement augmentation was performed in 96 % of reported levels. Significant improvement in mean scores for pain, disability and cancer-specific health-related quality of life from baseline to all time intervals was seen. NRPS improved from 5.9 to 2.1 (p < 0.0001). ODI improved from 52.9 to 37.0 (p < 0.08). FACT-G7 improved form 10.9 to 16.2 (p = 0.0001). FACT-BP improved from 22.6 to 38.9 (p < 0.001). No complications related to the procedure were reported.ConclusionRFA with cement augmentation safely and effectively reduces pain and disability rapidly, while increasing quality of life in patients suffering from vertebral body metastases.

  16. Computational modeling of radiofrequency ablation: evaluation on ex vivo data using ultrasound monitoring

    Science.gov (United States)

    Audigier, Chloé; Kim, Younsu; Dillow, Austin; Boctor, Emad M.

    2017-03-01

    Radiofrequency ablation (RFA) is the most widely used minimally invasive ablative therapy for liver cancer, but it is challenged by a lack of patient-specific monitoring. Inter-patient tissue variability and the presence of blood vessels make the prediction of the RFA difficult. A monitoring tool which can be personalized for a given patient during the intervention would be helpful to achieve a complete tumor ablation. However, the clinicians do not have access to such a tool, which results in incomplete treatment and a large number of recurrences. Computational models can simulate the phenomena and mechanisms governing this therapy. The temperature evolution as well as the resulted ablation can be modeled. When combined together with intraoperative measurements, computational modeling becomes an accurate and powerful tool to gain quantitative understanding and to enable improvements in the ongoing clinical settings. This paper shows how computational models of RFA can be evaluated using intra-operative measurements. First, simulations are used to demonstrate the feasibility of the method, which is then evaluated on two ex vivo datasets. RFA is simulated on a simplified geometry to generate realistic longitudinal temperature maps and the resulted necrosis. Computed temperatures are compared with the temperature evolution recorded using thermometers, and with temperatures monitored by ultrasound (US) in a 2D plane containing the ablation tip. Two ablations are performed on two cadaveric bovine livers, and we achieve error of 2.2 °C on average between the computed and the thermistors temperature and 1.4 °C and 2.7 °C on average between the temperature computed and monitored by US during the ablation at two different time points (t = 240 s and t = 900 s).

  17. Pulsed radiofrequency microwave fields around a quadrupole particle accelerator: measurement and safety evaluation

    International Nuclear Information System (INIS)

    Sachdev, R.N.; Swarup, G.; Rajan, K.K.; Joseph, L.

    1996-01-01

    Pulsed radiofrequency microwave radiation (RFMR) fields occur during the use of high power microwaves in plasma heating in fusion research, plasma and solid state diagnostics, particle accelerators and colliders, pump sources in lasers, material processing as well as in high power radars. This paper describes the experimental work done at Trombay for measurement of pulsed RFMR fields in the working area of a radiofrequency quadrupole (RFQ) accelerator with the use of a meter calibrated in continuous field and interprets the observed fields in the light of existing protection criteria for pulsed RFMR fields. (author)

  18. Percutaneous Renal Tumor Ablation: Radiation Exposure During Cryoablation and Radiofrequency Ablation

    Energy Technology Data Exchange (ETDEWEB)

    McEachen, James C., E-mail: james.mceachen2@gmail.com [Mayo Clinic, Division of Preventive, Occupational, and Aerospace Medicine (United States); Leng, Shuai; Atwell, Thomas D. [Mayo Clinic, Department of Radiology (United States); Tollefson, Matthew K. [Mayo Clinic, Department of Urology (United States); Friese, Jeremy L. [Mayo Clinic, Department of Radiology (United States); Wang, Zhen; Murad, M. Hassan [Mayo Clinic, Division of Preventive, Occupational, and Aerospace Medicine (United States); Schmit, Grant D. [Mayo Clinic, Department of Radiology (United States)

    2016-02-15

    IntroductionOnce reserved solely for non-surgical cases, percutaneous ablation is becoming an increasingly popular treatment option for a wider array of patients with small renal masses and the radiation risk needs to be better defined as this transition continues.Materials and MethodsRetrospective review of our renal tumor ablation database revealed 425 patients who underwent percutaneous ablation for treatment of 455 renal tumors over a 5-year time period. Imparted radiation dose information was reviewed for each procedure and converted to effective patient dose and skin dose using established techniques. Statistical analysis was performed with each ablative technique.ResultsFor the 331 cryoablation procedures, the mean DLP was 6987 mGycm (SD = 2861) resulting in a mean effective dose of 104.7 mSv (SD = 43.5) and the mean CTDI{sub vol} was 558 mGy (SD = 439) resulting in a mean skin dose of 563.2 mGy (SD = 344.1). For the 124 RFA procedures, the mean DLP was 3485 mGycm (SD = 1630) resulting in a mean effective dose of 50.3 mSv (SD = 24.0) and the mean CTDI{sub vol} was 232 mGy (SD = 149) resulting in a mean skin dose of 233.2 mGy (SD = 117.4). The difference in patient radiation exposure between the two renal ablation techniques was statistically significant (p < 0.001).ConclusionBoth cryoablation and RFA imparted an average skin dose that was well below the 2 Gy deterministic threshold for appreciable sequela. Renal tumor cryoablation resulted in a mean skin and effective radiation dose more than twice that for RFA. The radiation exposure for both renal tumor ablation techniques was at the high end of the medical imaging radiation dose spectrum.

  19. Evaluation of microneedling fractional radiofrequency device for treatment of acne scars

    Directory of Open Access Journals (Sweden)

    Byalekere Shivanna Chandrashekar

    2014-01-01

    Full Text Available Background: Various treatment modalities including non-invasive methods such as chemical peels, topical retinoids, microdermabrasion, minimally invasive techniques such as microneedling, fractional lasers, microneedling radiofrequency devices and invasive procedures such as acne scar surgeries and ablative lasers are used for acne scars, each with its own unique advantages and disadvantages. This study is a retrospective assessment of efficacy and safety of microneedling fractional radiofrequency in the treatment of acne scars. Methods: Thirty one patients of skin types III-V with moderate and severe facial acne scarring received four sequential fractional radiofrequency treatments over a period of 6 months with an interval of 6 weeks between each session. Goodman & Baron′s acne scar grading system was used for assessment by a side by side comparison of preoperative and post- operative photographs taken at their first visit and at the end of 3 months after the last session. Results: Estimation of improvement with Goodman and Baron′s Global Acne Scarring System showed that by qualitative assessment of 31 patients with grade 3 and grade 4 acne scars, 80.64% showed improvement by 2 grades and 19.35% showed improvement by 1 grade. Quantitative assessment showed that 58% of the patients had moderate, 29% had minimal, 9% had good and 3% showed very good improvement. Adverse effects were limited to transient pain, erythema, edema and hyperpigmentation. Conclusion: Microneedling fractional radiofrequency is efficacious for the treatment of moderate and severe acne scars.

  20. Assessment of personal exposure from radiofrequency-electromagnetic fields in Australia and Belgium using on-body calibrated exposimeters.

    Science.gov (United States)

    Bhatt, Chhavi Raj; Thielens, Arno; Billah, Baki; Redmayne, Mary; Abramson, Michael J; Sim, Malcolm R; Vermeulen, Roel; Martens, Luc; Joseph, Wout; Benke, Geza

    2016-11-01

    The purposes of this study were: i) to demonstrate the assessment of personal exposure from various RF-EMF sources across different microenvironments in Australia and Belgium, with two on-body calibrated exposimeters, in contrast to earlier studies which employed single, non-on-body calibrated exposimeters; ii) to systematically evaluate the performance of the exposimeters using (on-body) calibration and cross-talk measurements; and iii) to compare the exposure levels measured for one site in each of several selected microenvironments in the two countries. A human subject took part in an on-body calibration of the exposimeter in an anechoic chamber. The same subject collected data on personal exposures across 38 microenvironments (19 in each country) situated in urban, suburban and rural regions. Median personal RF-EMF exposures were estimated: i) of all microenvironments, and ii) across each microenvironment, in two countries. The exposures were then compared across similar microenvironments in two countries (17 in each country). The three highest median total exposure levels were: city center (4.33V/m), residential outdoor (urban) (0.75V/m), and a park (0.75V/m) [Australia]; and a tram station (1.95V/m), city center (0.95V/m), and a park (0.90V/m) [Belgium]. The exposures across nine microenvironments in Melbourne, Australia were lower than the exposures across corresponding microenvironments in Ghent, Belgium (p<0.05). The personal exposures across urban microenvironments were higher than those for rural or suburban microenvironments. Similarly, the exposure levels across outdoor microenvironments were higher than those for indoor microenvironments. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Selective Non-contact Field Radiofrequency Extended Treatment Protocol: Evaluation of Safety and Efficacy.

    Science.gov (United States)

    Moradi, Amir; Palm, Melanie

    2015-09-01

    Currently there are many non-invasive radiofrequency (RF) devices on the market that are utilized in the field of aesthetic medicine. At this time, there is only one FDA cleared device on the market that emits RF energy using a non-contact delivery system for circumferential reduction by means of adipocyte disruption. Innovation of treatment protocols is an integral part of aesthetic device development. However, when protocol modifications are made it is important to look at the safety as well as the potential for improved efficacy before initiating change. The purpose of this study was to evaluate the safety and efficacy of a newly designed extended treatment protocol using an operator independent selective non-contact RF device for the improvement in the contour and circumferential reduction of the abdomen and flanks (love handles). Twenty-five subjects enrolled in the IRB approved multi-center study to receive four weekly 45-minute RF treatments to the abdomen and love handles. Standardized digital photographs and circumference measurements were taken at baseline and at the 1- and 3-month follow-up visits. Biometric measurements including weight, hydration and body fat were obtained at baseline and each study visit. A subset of 4 subjects were randomly selected to undergo baseline serum lipid and liver-related blood tests with follow-up labs taken: 1 day post-treatment 1, 1 day post-treatment 4, and at the 1- and 3-month follow-up visits. Twenty-four subjects (22 female, 2 male), average age of 47.9 years (30-69 years), completed the study. The data of the twenty-four subjects revealed a statistically significant change in circumference P<.001 with an average decrease in circumference of 4.22cm at the 3-month follow-up visit. Lab values for the subset of 4 subjects remained relatively unchanged with only minor fluctuations noted in the serum lipid values in two of the subjects. Three independent evaluators viewed pre-treatment and 3-month post treatment

  2. Effects of 837 and 1950 MHz radiofrequency radiation exposure alone or combined on oxidative stress in MCF10A cells.

    Science.gov (United States)

    Hong, Mi-Na; Kim, Bong-Cho; Ko, Young-Gyu; Lee, Yun-Sil; Hong, Seung-Cheol; Kim, Taehong; Pack, Jeong-Ki; Choi, Hyung-Do; Kim, Nam; Lee, Jae-Seon

    2012-10-01

    The aim of this study was to determine whether the exposure to either single or multiple radio-frequency (RF) radiation frequencies could induce oxidative stress in cell cultures. Exposures of human MCF10A mammary epithelial cells to either a single frequency (837 MHz alone or 1950 MHz alone) or multiple frequencies (837 and 1950 MHz) were conducted at specific absorption rate (SAR) values of 4 W/kg for 2 h. During the exposure period, the temperature in the exposure chamber was maintained isothermally. Intracellular levels of reactive oxygen species (ROS), the antioxidant enzyme activity of superoxide dismutase (SOD), and the ratio of reduced/oxidized glutathione (GSH/GSSG) showed no statistically significant alterations as the result of either single or multiple RF radiation exposures. In contrast, ionizing radiation-exposed cells, used as a positive control, showed evident changes in all measured biological endpoints. These results indicate that single or multiple RF radiation exposure did not elicit oxidative stress in MCF10A cells under our exposure conditions. Copyright © 2012 Wiley Periodicals, Inc.

  3. CT Perfusion for Early Response Evaluation of Radiofrequency Ablation of Focal Liver Lesions: First Experience

    Energy Technology Data Exchange (ETDEWEB)

    Marquez, Herman P., E-mail: hermanpaulo.marquezmasquiaran@usz.ch; Puippe, Gilbert; Mathew, Rishi Philip; Alkadhi, Hatem; Pfammatter, Thomas; Fischer, Michael A. [University Hospital Zurich, Department of Diagnostic and Interventional Radiology, Institute of Diagnostic and Interventional Radiology (Switzerland)

    2017-01-15

    PurposeTo investigate the value of perfusion CT (P-CT) for early assessment of treatment response in patients undergoing radiofrequency ablation (RFA) of focal liver lesions.Methods and Materials20 consecutive patients (14 men; mean age 64 ± 14) undergoing P-CT within 24 h after RFA of liver metastases (n = 10) or HCC (n = 10) were retrospectively included. Two readers determined arterial liver perfusion (ALP, mL/min/100 mL), portal liver perfusion (PLP, mL/min/100 mL), and hepatic perfusion index (HPI, %) in all post-RFA lesions by placing a volume of interest in the necrotic central (CZ), the transition (TZ), and the surrounding parenchymal (PZ) zone. Patients were classified into complete responders (no residual tumor) and incomplete responders (residual/progressive tumor) using imaging follow-up with contrast-enhanced CT or MRI after a mean of 57 ± 30 days. Prediction of treatment response was evaluated using the area under the curve (AUC) from receiver operating characteristic analysis.ResultsMean ALP/PLP/HPI of both readers were 4.8/15.4/61.2 for the CZ, 9.9/16.8/66.3 for the TZ and 20.7/29.0/61.8 for the PZ. Interreader agreement of HPI was fair for the CZ (intraclass coefficient 0.713), good for the TZ (0.813), and excellent for the PZ (0.920). For both readers, there were significant differences in HPI of the CZ and TZ between responders and nonresponders (both, P < 0.05). HPI of the TZ showed the highest AUC (0.911) for prediction of residual tumor, suggesting a cut-off value of 76 %.ConclusionIncreased HPI of the transition zone assessed with P-CT after RFA might serve as an early quantitative biomarker for residual tumor in patients with focal liver lesions.

  4. Evaluation of left atrial linear ablation using contiguous and optimized radiofrequency lesions: the ALINE study.

    Science.gov (United States)

    Wolf, Michael; El Haddad, Milad; Fedida, Joël; Taghji, Philippe; Van Beeumen, Katarina; Strisciuglio, Teresa; De Pooter, Jan; Lepièce, Caroline; Vandekerckhove, Yves; Tavernier, René; Duytschaever, Mattias; Knecht, Sébastien

    2018-01-08

    Achieving block across linear lesions is challenging. We prospectively evaluated radiofrequency (RF) linear ablation at the roof and mitral isthmus (MI) using point-by-point contiguous and optimized RF lesions. Forty-one consecutive patients with symptomatic persistent AF underwent stepwise contact force (CF)-guided catheter ablation during ongoing AF. A single linear set of RF lesions was delivered at the roof and posterior MI according to the 'Atrial LINEar' (ALINE) criteria, i.e. point-by-point RF delivery (up to 35 W) respecting strict criteria of contiguity (inter-lesion distance ≤ 6 mm) and indirect lesion depth assessment (ablation index ≥550). We assessed the incidence of bidirectional block across both lines only after restoration of sinus rhythm. After a median RF time of 7 min [interquartile range (IQR) 5-9], first-pass block across roof lines was observed in 38 of 41 (93%) patients. Final bidirectional roof block was achieved in 40 of 41 (98%) patients. First-pass block was observed in 8 of 35 (23%) MI lines, after a median RF time of 8 min (IQR 7-12). Additional endo- and epicardial (54% of patients) RF applications resulted in final bidirectional MI block in 28 of 35 (80%) patients. During a median follow-up of 396 (IQR 310-442) days, 12 patients underwent repeat procedures, with conduction recovery in 4 of 12 and 5 of 10 previously blocked roof lines and MI lines, respectively. No complications occurred. Anatomical linear ablation using contiguous and optimized RF lesions results in a high rate of first-pass block at the roof but not at the MI. Due to its complex 3D architecture, the MI frequently requires additional endo- and epicardial RF lesions to be blocked. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2018. For permissions, please email: journals.permissions@oup.com.

  5. Numerical analysis on the effect of angle of attack on evaluating radio-frequency blackout in atmospheric reentry

    Science.gov (United States)

    Jung, Minseok; Kihara, Hisashi; Abe, Ken-ichi; Takahashi, Yusuke

    2016-06-01

    A three-dimensional numerical simulation model that considers the effect of the angle of attack was developed to evaluate plasma flows around reentry vehicles. In this simulation model, thermochemical nonequilibrium of flowfields is considered by using a four-temperature model for high-accuracy simulations. Numerical simulations were performed for the orbital reentry experiment of the Japan Aerospace Exploration Agency, and the results were compared with experimental data to validate the simulation model. A comparison of measured and predicted results showed good agreement. Moreover, to evaluate the effect of the angle of attack, we performed numerical simulations around the Atmospheric Reentry Demonstrator of the European Space Agency by using an axisymmetric model and a three-dimensional model. Although there were no differences in the flowfields in the shock layer between the results of the axisymmetric and the three-dimensional models, the formation of the electron number density, which is an important parameter in evaluating radio-frequency blackout, was greatly changed in the wake region when a non-zero angle of attack was considered. Additionally, the number of altitudes at which radio-frequency blackout was predicted in the numerical simulations declined when using the three-dimensional model for considering the angle of attack.

  6. Radiofrequency: Thermage.

    Science.gov (United States)

    Polder, Kristel D; Bruce, Suzanne

    2011-05-01

    Nonablative procedures for facial rejuvenation have become increasingly popular. One such method to improve laxity and diminish rhytids is monopolar capacitively coupled radiofrequency (MRF). The authors discuss clinical studies using MRF. The authors also discuss their clinical experiences as well as recommendations for optimal results. MRF using the Thermage CPT system (Solta Medical, Hayward, California) offers minimal downtime with a favorable side-effect profile. Although there are many radiofrequency devices on the market for aesthetic use, MRF has the most clinical trials to date to support its use as an effective, evidence-based modality to improve rhytids and tighten the skin. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Radiofrequency electromagnetic radiation exposure effects on amygdala morphology, place preference behavior and brain caspase-3 activity in rats.

    Science.gov (United States)

    Narayanan, Sareesh Naduvil; Mohapatra, Nirupam; John, Pamala; K, Nalini; Kumar, Raju Suresh; Nayak, Satheesha B; Bhat, P Gopalakrishna

    2018-03-01

    The purpose of the study was to evaluate the changes in amygdala morphology and emotional behaviors, upon exposure to chronic RF-EMR in adolescent rats. Four weeks old male albino Wistar rats were exposed to 900 MHz (power density:146.60 μW/cm2) from a mobile phone in silent-mode for 28 days. Amygdala morphology was studied using cresyl violet, TUNEL and Golgi-Cox staining. Place preference behavior was studied using light/dark chamber test and following this brain caspase-3 activity was determined. Number of healthy neurons was decreased in the basolateral amygdala and cortical amygdala but not in the central amygdala after RF-EMR exposure. It also induced apoptosis in the amygdala. RF-EMR exposure altered dendritic arborization pattern in basolateral amygdala but not in the central amygdala. Altered place preference and hyperactivity-like behavior was evident after RF-EMR exposure, but brain caspase-3 activity did not change. RF-EMR exposure perturbed normal cellular architecture of amygdala and this was associated with altered place preference. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Clinical evaluation of the efficacy and safety of fractional bipolar radiofrequency for the treatment of moderate to severe acne scars.

    Science.gov (United States)

    Verner, Ines

    2016-01-01

    Several treatment modalities are used for the treatment of acne scars with variable results. Recent studies showed that fractional radiofrequency may be an effective treatment modality for acne scars. The objective of this study was to assess the efficacy, safety, tolerability and patient satisfaction of fractional bipolar radiofrequency (RF), the eTwo™ system (Syneron Candela Ltd., Yokneam, Israel) for treating acne scars. Twelve patients with moderate to severe acne scars received 3-5 treatments with the Sublative fractionated bipolar RF applicator of the eTwo device at 1-month intervals. Patients were evaluated clinically and photographically at each visit and 3 months after the final treatment. Very good improvement (at least one scale) was seen after completing the five treatments. The patient satisfaction survey (Global Aesthetic Improvement Scale scores) revealed that half (6 out of 12) of the patients reported to be satisfied with treatment results, while the other half reported to be very satisfied. Beyond the expected erythema and minimal scab formation in the treated areas, which was mild and transient, none of the participants reported any adverse events. The data presented here support the high efficacy and safety of fractionated bipolar RF for the aesthetic improvement of moderate to severe acne scars. © 2015 Wiley Periodicals, Inc.

  9. Effects of prenatal and postnatal exposure to GSM-like radiofrequency on blood chemistry and oxidative stress in infant rabbits, an experimental study.

    Science.gov (United States)

    Ozgur, Elcin; Kismali, Gorkem; Guler, Goknur; Akcay, Aytac; Ozkurt, Guzin; Sel, Tevhide; Seyhan, Nesrin

    2013-11-01

    We aimed to investigate the potential hazardous effects of prenatal and/or postnatal exposure to 1800 MHz GSM-like radiofrequency radiation (RFR) on the blood chemistry and lipid peroxidation levels of infant rabbits. A total of 72 New Zealand female and male white rabbits aged 1-month were used. Thirty-six female and 36 male were divided into four groups which were composed of nine infants: (i) Group 1 were the sham exposure (control), (ii) Group 2 were exposed to RFR, 15 min daily for 7 days in the prenatal period (between 15th and 22nd days of the gestational period) (prenatal exposure group). (iii) Group 3 were exposed to RFR 15 min/day (14 days for male, whereas 7 days for female) after they reached 1-month of age (postnatal exposure group). (iv) Group 4 were exposed to RFR for 15 min daily during 7 days in the prenatal period (between 15th and 22nd days of the gestational period) and 15 min/day (14 days for male, whereas 7 days for female) after they reached 1-month of age (prenatal and postnatal exposure group). Results showed that serum lipid peroxidation level in both female and male rabbits changed due to the RFR exposure. However, different parameters of the blood biochemistry were affected by exposure in male and female infants. Consequently, the whole-body 1800 MHz GSM-like RFR exposure may lead to oxidative stress and changes on some blood chemistry parameters. Studies on RFR exposure during prenatal and postnatal periods will help to establish international standards for the protection of pregnants and newborns from environmental RFR.

  10. Survey of the Effects of Exposure to 900 MHz Radiofrequency Radiation Emitted by a GSM Mobile Phone on the Pattern of Muscle Contractions in an Animal Model.

    Science.gov (United States)

    Mortazavi, S M J; Rahimi, S; Talebi, A; Soleimani, A; Rafati, A

    2015-09-01

    The rapid development of wireless telecommunication technologies over the past decades, has led to significant changes in the exposure of the general public to electromagnetic fields. Nowadays, people are continuously exposed to different sources of electromagnetic fields such as mobile phones, mobile base stations, cordless phones, Wi-Fi routers, and power lines. Therefore, the last decade witnessed a rapidly growing concern about the possible health effects of exposure to electromagnetic fields emitted by these sources. In this study that was aimed at investigating the effects of exposure to radiofrequency (RF) radiation emitted by a GSM mobile phone on the pattern of contraction in frog's isolated gastrocnemius muscle after stimulation with single square pulses of 1V (1 Hz), pulse height of contractions, the time interval between two subsequent contractions and the latency period were measured. Our findings showed that the pulse height of contractions muscle could be affected by the exposure to electromagnetic fields. Especially, the latency period was effectively altered in RF-exposed samples. However, none of the experiments could show an alteration in the time interval between two subsequent contractions after exposure to electromagnetic fields. These findings support early reports which indicated a wide variety of non-thermal effects of electromagnetic radiation on amphibians including the effects on the pattern of muscle extractions.

  11. Eight hours of nocturnal 915 MHz radiofrequency identification (RFID) exposure reduces urinary levels of melatonin and its metabolite via pineal arylalkylamine N-acetyltransferase activity in male rats.

    Science.gov (United States)

    Kim, Hye Sun; Paik, Man-Jeong; Lee, Yu Hee; Lee, Yun-Sil; Choi, Hyung Do; Pack, Jeong-Ki; Kim, Nam; Ahn, Young Hwan

    2015-01-01

    We investigated the effects of whole-body exposure to the 915 MHz radiofrequency identification (RFID) on melatonin biosynthesis and the activity of rat pineal arylalkylamine N-acetyltransferase (AANAT). Rats were exposed to RFID (whole-body specific absorption rate, 4 W/kg) for 8 h/day, 5 days/week, for weeks during the nighttime. Total volume of urine excreted during a 24-h period was collected after RFID exposure. Urinary melatonin and 6-hydroxymelatonin sulfate (6-OHMS) was measured by gas chromatography-mass spectrometry (GC-MS) and enzyme-linked immunosorbent assay (ELISA), respectively. AANAT enzyme activity was measured using liquid biphasic dif-13 fusion assay. Protein levels and mRNA expression of AANAT was 14 measured by Western blot and reverse transcription polymerase 15 chain reaction (RT-PCR) analysis, respectively. Eight hours of nocturnal RFID exposure caused a significant reduction in both urinary melatonin (p = 0. 003) and 6-OHMS (p = 0. 026). Activity, protein levels, and mRNA expression of AANAT were suppressed by exposure to RFID (p RFID exposure can cause reductions in the levels of both urinary melatonin and 6-OHMS, possibly due to decreased melatonin biosynthesis via suppression of Aanat gene transcription in the rat pineal gland.

  12. Survey of the Effects of Exposure to 900 MHz Radiofrequency Radiation Emitted by a GSM Mobile Phone on the Pattern of Muscle Contractions in an Animal Model

    Directory of Open Access Journals (Sweden)

    Mortazavi S. M. J.

    2015-09-01

    Full Text Available Background: The rapid development of wireless telecommunication technologies over the past decades, has led to significant changes in the exposure of the general public to electromagnetic fields. Nowadays, people are continuously exposed to different sources of electromagnetic fields such as mobile phones, mobile base stations, cordless phones, Wi-Fi routers, and power lines. Therefore, the last decade witnessed a rapidly growing concern about the possible health effects of exposure to electromagnetic fields emitted by these sources. Materials and Methods: In this study that was aimed at investigating the effects of exposure to radiofrequency (RF radiation emitted by a GSM mobile phone on the pattern of contraction in frog’s isolated gastrocnemius muscle after stimulation with single square pulses of 1V (1 Hz, pulse height of contractions, the time interval between two subsequent contractions and the latency period were measured. Results: Our findings showed that the pulse height of contractions muscle could be affected by the exposure to electromagnetic fields. Especially, the latency period was effectively altered in RF-exposed samples. However, none of the experiments could show an alteration in the time interval between two subsequent contractions after exposure to electromagnetic fields. Conclusion: These findings support early reports which indicated a wide variety of non-thermal effects of electromagnetic radiation on amphibians including the effects on the pattern of muscle extractions

  13. Efficacy and safety evaluation of an innovative CO2 laser/radiofrequency device in dermatology.

    Science.gov (United States)

    Campolmi, P; Bonan, P; Cannarozzo, G; Bruscino, N; Moretti, S

    2013-12-01

    CO2 laser has not only become the most widely used laser in dermatological surgical practice, but it has also proved to be highly effective in treating aesthetic imperfections. To examine the efficacy and safety of a novel fractional CO2 laser combined with a radiofrequency device in different dermatological, surgical and aesthetic fields. A total of 79 patients were treated in our Outpatient Service with a novel fractional CO2 laser combined with a bipolar radiofrequency device for a maximum of 5 months. Group A consisted of 39 patients with lesions requiring complete excision, whereas Group B consisted of 40 subjects seeking to enhance aesthetic facial imperfections. The results were assessed by three 'blind' investigators using photographs and clinical observations; in addition, the patients had to give their own subjective assessment of the results. At the 6-month follow-up, the lesions of the Group A patients had been completely removed, except for one case of a large sebaceous nevus on the scalp. All the Group B patients showed global improvement in skin tightening, removal of fine lines and rhytides and correction of dilated pores and hyperpigmentation, with no significant side-effects and short downtimes. This kind of laser meets the needs of the majority of dermatologists requiring a unique, versatile tool to remove cutaneous lesions and at the same time, safely and effectively treat skin imperfections. © 2012 The Authors. Journal of the European Academy of Dermatology and Venereology © 2012 European Academy of Dermatology and Venereology.

  14. Evaluation of the Effect of Duration on the Efficacy of Pulsed Radiofrequency in an Animal Model of Neuropathic Pain.

    Science.gov (United States)

    Ramzy, Eiad A; Khalil, Khaled I; Nour, Eman M; Hamed, Mohammed F; Taha, Mohamed A

    2018-03-01

    Pulsed radiofrequency (PRF) is increasingly used in clinical practice, especially in neuropathic pain disorders. Although PRF is not new to clinical use, there are significant gaps in knowledge regarding its effectiveness. The current study was conducted to evaluate the effect of duration of application of PRF on its analgesic efficacy in improvement of neuropathic pain. A randomized experimental trial. An animal research facility at the College of Veterinary Medicine at Mansoura University in Egypt. Chronic constriction of the sciatic nerve of 36 male Sprague-Dawley rats was performed to induce neuropathic pain. The rats were divided into 6 groups (6 rats each) in which PRF was applied for 2, 4, 6, or 8 minutes or not at all. In one group, RF cannula was applied without performing PRF intervention. The pain was assessed through observation of resting paw posture (RPP) at 3, 10, and 21 days. Nerve damage was assessed by histopathological evaluation of the sciatic nerve. Immunohistochemical localization of proinflammatory cytokines (interleukin 6 [IL-6] and tumor necrosis factor alpha [TNF-alpha]) was also done. RPP was improved in rats treated with PRF. This improvement was significant only in rats treated for 8 minutes. Increased duration for PRF application was associated with a significant decrease in IL-6 and TNF-alpha contents in all groups when compared with the control group. Histopathological evaluation of the constricted sciatic nerve revealed no statistical significance among the different study groups. The study was limited by the lack of measurement of other inflammatory markers that may help elucidate other relevant mechanisms. Increased duration of PRF application resulted in better analgesic efficacy without any increase in tissue injury in an animal model of neuropathic pain. This effect may be attributed to decreased production of pro-inflammatory cytokines. Pulsed radiofrequency, analgesic, rats, sciatic nerve, duration, neuropathic pain.

  15. Klebsiella pneumonia, a Microorganism that Approves the Non-linear Responses to Antibiotics and Window Theory after Exposure to Wi-Fi 2.4 GHz Electromagnetic Radiofrequency Radiation.

    Science.gov (United States)

    Taheri, M; Mortazavi, S M J; Moradi, M; Mansouri, Sh; Nouri, F; Mortazavi, S A R; Bahmanzadegan, F

    2015-09-01

    Drug resistance is widely believed to be an increasingly serious threat to global public health. We have previously reported that short term exposure of microorganisms to diagnostic ultrasound waves could significantly alter their sensitivity to antibiotics. In our previous studies, Klebsiella pneumoniae showed major differences in the sensitivity to antibiotics in exposed and non-exposed samples. This study was aimed at investigating the alteration of antibiotic resistance of Klebsiella pneumonia, after exposure to Wi-Fi 2.4 GHz electromagnetic radiofrequency radiation. In this in vitro study, three replicate agar plates were used for each test. The antibiotic susceptibility test was carried out using disc diffusion method on Mueller Hinton agar plates and the inhibition zones in both control and exposed groups were measured. A common Wi-Fi router was used in this study as the radiofrequency exposure source. Irradiated samples were exposed to Wi-Fi radiofrequency radiation for 3, 4.5 and 8 hours. Statistically significant variations of sensitivity to antibiotics were found for all studied antibiotics after 4.5 hours of RF exposure, compared to non-exposed bacteria. Interestingly, the mean diameters of the inhibition zones after 3 hours of exposure were less than those exposed for 4.5 hours. Following this rise in the sensitivity to antibiotics, a fall was observed in the bacteria exposed for 8 hours for all studied antibiotics. The findings of this study show a statistically significant rise in the sensitivity of Klebsiella pneumoniae to different antibiotics after 4.5 hours of exposure to 2.4 GHz Wi-Fi radiation, followed by a fall after 8 hours of exposure. These observations can be interpreted by the concept of non-linearity in the responses of Klebsiella pneumoniae to different antibiotics after exposure to electromagnetic radiofrequency radiation. As in this study a minimum level of effect was needed for the induction of adaptive response, these results also

  16. Evaluation of MRI issues for an access port with a radiofrequency identification (RFID) tag.

    Science.gov (United States)

    Titterington, Blake; Shellock, Frank G

    2013-10-01

    A medical implant that contains metal, such as an RFID tag, must undergo proper MRI testing to ensure patient safety and to determine that the function of the RFID tag is not compromised by exposure to MRI conditions. Therefore, the objective of this investigation was to assess MRI issues for a new access port that incorporates an RFID tag. Samples of the access port with an RFID tag (Medcomp Power Injectable Port with CertainID; Medcomp, Harleysville, PA) were evaluated using standard protocols to assess magnetic field interactions (translational attraction and torque; 3-T), MRI-related heating (3-T), artifacts (3-T), and functional changes associated with different MRI conditions (nine samples, exposed to different MRI conditions at 1.5-T and 3-T). Magnetic field interactions were not substantial and will pose no hazards to patients. MRI-related heating was minimal (highest temperature change, 1.7°C; background temperature rise, 1.6°C). Artifacts were moderate in size in relation to the device. Exposures to MRI conditions at 1.5-T and 3-T did not alter or damage the functional aspects of the RFID tag. Based on the findings of the test, this new access port with an RFID tag is acceptable (or, MR conditional, using current MRI labeling terminology) for patients undergoing MRI examinations at 1.5-T/64-MHz and 3-T/128-MHz. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Association between exposure to radiofrequency electromagnetic fields assessed by dosimetry and acute symptoms in children and adolescents: a population based cross-sectional study

    Directory of Open Access Journals (Sweden)

    Radon Katja

    2010-11-01

    Full Text Available Abstract Background The increase in numbers of mobile phone users was accompanied by some concern that exposure to radiofrequency electromagnetic fields (RF EMF might adversely affect acute health especially in children and adolescents. The authors investigated this potential association using personal dosimeters. Methods A 24-hour exposure profile of 1484 children and 1508 adolescents was generated in a population-based cross-sectional study in Germany between 2006 and 2008 (participation 52%. Personal interview data on socio-demographic characteristics, self-reported exposure and potential confounders were collected. Acute symptoms were assessed twice during the study day using a symptom diary. Results Only few of the large number of investigated associations were found to be statistically significant. At noon, adolescents with a measured exposure in the highest quartile during morning hours reported a statistically significant higher intensity of headache (Odd Ratio: 1.50; 95% confidence interval: 1.03, 2.19. At bedtime, adolescents with a measured exposure in the highest quartile during afternoon hours reported a statistically significant higher intensity of irritation in the evening (4th quartile 1.79; 1.23, 2.61, while children reported a statistically significant higher intensity of concentration problems (4th quartile 1.55; 1.02, 2.33. Conclusions We observed few statistically significant results which are not consistent over the two time points. Furthermore, when the 10% of the participants with the highest exposure are taken into consideration the significant results of the main analysis could not be confirmed. Based on the pattern of these results, we assume that the few observed significant associations are not causal but rather occurred by chance.

  18. Radiation Exposure of Interventional Radiologists During Computed Tomography Fluoroscopy-Guided Renal Cryoablation and Lung Radiofrequency Ablation: Direct Measurement in a Clinical Setting

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, Yusuke, E-mail: wckyh140@yahoo.co.jp; Hiraki, Takao, E-mail: takaoh@tc4.so-net.ne.jp; Gobara, Hideo, E-mail: gobara@cc.okayama-u.ac.jp; Iguchi, Toshihiro, E-mail: i10476@yahoo.co.jp; Fujiwara, Hiroyasu, E-mail: hirofujiwar@gmail.com; Kawabata, Takahiro, E-mail: tkhr-kwbt@yahoo.co.jp [Okayama University Medical School, Department of Radiology (Japan); Yamauchi, Takatsugu, E-mail: me9248@hp.okayama-u.ac.jp; Yamaguchi, Takuya, E-mail: me8738@hp.okayama-u.ac.jp [Okayama University Hospital, Central Division of Radiology (Japan); Kanazawa, Susumu, E-mail: susumu@cc.okayama-u.ac.jp [Okayama University Medical School, Department of Radiology (Japan)

    2016-06-15

    IntroductionComputed tomography (CT) fluoroscopy-guided renal cryoablation and lung radiofrequency ablation (RFA) have received increasing attention as promising cancer therapies. Although radiation exposure of interventional radiologists during these procedures is an important concern, data on operator exposure are lacking.Materials and MethodsRadiation dose to interventional radiologists during CT fluoroscopy-guided renal cryoablation (n = 20) and lung RFA (n = 20) was measured prospectively in a clinical setting. Effective dose to the operator was calculated from the 1-cm dose equivalent measured on the neck outside the lead apron, and on the left chest inside the lead apron, using electronic dosimeters. Equivalent dose to the operator’s finger skin was measured using thermoluminescent dosimeter rings.ResultsThe mean (median) effective dose to the operator per procedure was 6.05 (4.52) μSv during renal cryoablation and 0.74 (0.55) μSv during lung RFA. The mean (median) equivalent dose to the operator’s finger skin per procedure was 2.1 (2.1) mSv during renal cryoablation, and 0.3 (0.3) mSv during lung RFA.ConclusionRadiation dose to interventional radiologists during renal cryoablation and lung RFA were at an acceptable level, and in line with recommended dose limits for occupational radiation exposure.

  19. A New Radiofrequency Ablation Procedure to Treat Sacroiliac Joint Pain.

    Science.gov (United States)

    Cheng, Jianguo; Chen, See Loong; Zimmerman, Nicole; Dalton, Jarrod E; LaSalle, Garret; Rosenquist, Richard

    2016-01-01

    Low back pain may arise from disorders of the sacroiliac joint in up to 30% of patients. Radiofrequency ablation (RFA) of the nerves innervating the sacroiliac joint has been shown to be a safe and efficacious strategy. We aimed to develop a new RFA technique to relieve low back pain secondary to sacroiliac joint disorders. Methodology development with validation through prospective observational non-randomized trial (PONRT). Academic multidisciplinary health care system, Ohio, USA. We devised a guide-block to facilitate accurate placement of multiple electrodes to simultaneously ablate the L5 dorsal ramus and lateral branches of the S1, S2, and S3 dorsal rami. This was achieved by bipolar radiofrequency ablation (b-RFA) to create a strip lesion from the lateral border of the base of the sacral superior articular process (L5-S1 facet joint) to the lateral border of the S3 sacral foramen. We applied this technique in 31 consecutive patients and compared the operating time, x-ray exposure time and dose, and clinical outcomes with patients (n = 62) who have been treated with the cooled radiofrequency technique. Patients' level of pain relief was reported as 80% pain relief at one, 3, 6, and 12 months after the procedure. The relationship between RFA technique and duration of pain relief was evaluated using interval-censored multivariable Cox regression. The new technique allowed reduction of operating time by more than 50%, x-ray exposure time and dose by more than 80%, and cost by more than $1,000 per case. The percent of patients who achieved > 50% pain reduction was significantly higher in the b-RFA group at 3, 6, and 12 months follow-up, compared to the cooled radiofrequency group. No complications were observed in either group. Although the major confounding factors were taken into account in the analysis, use of historical controls does not balance observed and unobserved potential confounding variables between groups so that the reported results are potentially

  20. Evaluation of the Effects of Radio-Frequency Identification Technology on Patient Tracking in Hospitals: A Systematic Review.

    Science.gov (United States)

    Ebrahimzadeh, Fahimeh; Nabovati, Ehsan; Hasibian, Mohammad Reza; Eslami, Saeid

    2017-12-15

    The aim of this study was to systematically review all studies that evaluated the effects of using radio-frequency identification (RFID) for tracking patients in hospitals. The PubMed and Embase databases were searched (to August 2015) for relevant English language studies, and those that evaluated the effects of a real-time locating systems with RFID for patient tracking in hospitals were identified and extracted. Of the 652 studies found, the 17 relevant studies were extracted for inclusion. Five of the extracted studies used RFID systems in operating theaters, two in emergency departments, one in a magnetic resonance imaging department, one in a radiology room, and the remaining eight studies were in other wards. In these studies, features such as the feasibility, accuracy, precision, reliability, security, level of satisfaction, cost of care, and time efficiency of the RFID systems were reported. Of all the extracted studies, seven evaluated the accuracy of the systems in crowded and unattended areas, and five of these were satisfied with their accuracy. Six evaluated the reliability of the systems, and all of these found the systems to be reliable. Six evaluated time-savings, and all of them reported the systems to be time effective. Two focused on the cost of care, and both of these reported the systems to be cost effective. Although most studies reported a positive impact on the accuracy and precision of patient identification, there is insufficient good evidence to show that RFID systems can accurately localize patients in crowded settings.

  1. Effect of cell phone radiofrequency radiation on body temperature in rodents: Pilot studies of the National Toxicology Program's reverberation chamber exposure system.

    Science.gov (United States)

    Wyde, Michael E; Horn, Thomas L; Capstick, Myles H; Ladbury, John M; Koepke, Galen; Wilson, Perry F; Kissling, Grace E; Stout, Matthew D; Kuster, Niels; Melnick, Ronald L; Gauger, James; Bucher, John R; McCormick, David L

    2018-04-01

    Radiofrequency radiation (RFR) causes heating, which can lead to detrimental biological effects. To characterize the effects of RFR exposure on body temperature in relation to animal size and pregnancy, a series of short-term toxicity studies was conducted in a unique RFR exposure system. Young and old B6C3F1 mice and young, old, and pregnant Harlan Sprague-Dawley rats were exposed to Global System for Mobile Communication (GSM) or Code Division Multiple Access (CDMA) RFR (rats = 900 MHz, mice = 1,900 MHz) at specific absorption rates (SARs) up to 12 W/kg for approximately 9 h a day for 5 days. In general, fewer and less severe increases in body temperature were observed in young than in older rats. SAR-dependent increases in subcutaneous body temperatures were observed at exposures ≥6 W/kg in both modulations. Exposures of  ≥10 W/kg GSM or CDMA RFR induced excessive increases in body temperature, leading to mortality. There was also a significant increase in the number of resorptions in pregnant rats at 12 W/kg GSM RFR. In mice, only sporadic increases in body temperature were observed regardless of sex or age when exposed to GSM or CDMA RFR up to 12 W/kg. These results identified SARs at which measurable RFR-mediated thermal effects occur, and were used in the selection of exposures for subsequent toxicology and carcinogenicity studies. Bioelectromagnetics. 39:190-199, 2018. © 2018 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc. © 2018 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc.

  2. Evaluation of radio-frequency heating in controlling Salmonella enterica in raw shelled almonds.

    Science.gov (United States)

    Jeong, Seul-Gi; Baik, Oon-Doo; Kang, Dong-Hyun

    2017-08-02

    This study was conducted to investigate the efficacy of radio-frequency (RF) heating to reduce Salmonella enterica serovars Enteritidis, Typhimurium, and Senftenberg in raw shelled almonds compared to conventional convective heating, and the effect of RF heating on quality by measuring changes in the color and degree of lipid oxidation. Agar-grown cells of three pathogens were inoculated onto the surface or inside of raw shelled almonds using surface inoculation or the vacuum perfusion method, respectively, and subjected to RF or conventional heating. RF heating for 40s achieved 3.7-, 6.0-, and 5.6-log reductions in surface-inoculated S. Enteritidis, S. Typhimurium, and S. Senftenberg, respectively, whereas the reduction of these pathogens following convective heating for 600s was 1.7, 2.5, and 3.7 log, respectively. RF heating reduced internally inoculated pathogens to below the detection limit (0.7 logCFU/g) after 30s. However, conventional convective heating did not attain comparable reductions even at the end of treatment (600s). Color values, peroxide values, and acid values of RF-treated (40-s treatment) almonds were not significantly (P>0.05) different from those of nontreated samples. These results suggest that RF heating can be applied to control internalized pathogens as well as surface-adhering pathogens in raw almonds without affecting product quality. Copyright © 2017. Published by Elsevier B.V.

  3. Radiofrequency-Based Identification Medical Device: An Evaluable Solution for Surgical Sponge Retrieval?

    Science.gov (United States)

    Lazzaro, Alessandra; Corona, Arianna; Iezzi, Luca; Quaresima, Silvia; Armisi, Luca; Piccolo, Ilaria; Medaglia, Carlo Maria; Sbrenni, Sergio; Sileri, Pierpaolo; Rosato, Nicola; Gaspari, Achille Lucio; Di Lorenzo, Nicola

    2017-06-01

    A retained surgical item in patients (gossypiboma) is a persisting problem, despite consistent improvements and existing guidelines in counting instruments and sponges. Previous experiences with radiofrequency identification technology (RFID) tracking sponges show that it could represent an innovation, in order to reduce the criticism and increase the effectiveness during surgical procedures. We present an automated system that allows reduction of errors and improves safety in the operating room. The system consists of 3 antennas, surgical sponges containing RFID tags, and dedicated software applications, with Wi-Fi real-time communication between devices. The first antenna provides the initial count of gauzes; the second a real-time counting during surgery, including the sponges thrown into the kick-bucket; and the third can be used in the event of uneven sponge count. The software allows management at all stages of the process. In vitro and in vivo tests were performed: the system provided excellent results in detecting sponges in patients' body. Hundred percent retained sponges were detected correctly, even when they were overlapped. No false positive or false negative was recorded. The counting procedure turned out to be more streamlined and efficient and it could save time in a standard procedure. The RFID system for sponge tracking was shown to be experimentally a reliable and feasible method to track sponges with a full detection accuracy in the operating room. The results indicate the system to be safe and effective with acceptable cost-effective parameters.

  4. Feasibility of Extracted-Overlay Fusion Imaging for Intraoperative Treatment Evaluation of Radiofrequency Ablation for Hepatocellular Carcinoma.

    Science.gov (United States)

    Makino, Yuki; Imai, Yasuharu; Igura, Takumi; Kogita, Sachiyo; Sawai, Yoshiyuki; Fukuda, Kazuto; Iwamoto, Takayuki; Okabe, Junya; Takamura, Manabu; Fujita, Norihiko; Hori, Masatoshi; Takehara, Tetsuo; Kudo, Masatoshi; Murakami, Takamichi

    2016-10-01

    Extracted-overlay fusion imaging is a novel computed tomography/magnetic resonance-ultrasonography (CT/MR-US) imaging technique in which a target tumor with a virtual ablative margin is extracted from CT/MR volume data and synchronously overlaid on US images. We investigated the applicability of the technique to intraoperative evaluation of radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). This retrospective study analyzed 85 HCCs treated with RFA using extracted-overlay fusion imaging for guidance and evaluation. To perform RFA, an electrode was inserted targeting the tumor and a virtual 5-mm ablative margin overlaid on the US image. Following ablation, contrast-enhanced US (CEUS) was performed to assess the ablative margin, and the minimal ablative margins were categorized into three groups: (I) margin overlay fusion imaging and CT-CT/MR-MR fusion imaging were in agreement for 72 tumors (91.1%) (Cohen's quadratic-weighted kappa coefficient 0.66, good agreement, poverlay fusion imaging combined with CEUS is feasible for the evaluation of RFA and enables intraoperative treatment evaluation without the need to perform contrast-enhanced CT.

  5. New Horizons in Enhancing the Proliferation and Differentiation of Neural Stem Cells Using Stimulatory Effects of the Short Time Exposure to Radiofrequency Radiation.

    Science.gov (United States)

    Eghlidospour, M; Mortazavi, S M J; Yousefi, F; Mortazavi, S A R

    2015-09-01

    Mobile phone use and wireless communication technology have grown explosively over the past decades. This rapid growth has caused widespread global concern about the potential detrimental effects of this technology on human health. Stem cells generate specialized cell types of the tissue in which they reside through normal differentiation pathways. Considering the undeniable importance of stem cells in modern medicine, numerous studies have been performed on the effects of ionizing and non-ionizing radiation on cellular processes such as: proliferation, differentiation, cell cycle and DNA repair processes. We have conducted extensive studies on beneficial (stimulatory) or detrimental biological effects of exposure to different sources of electromagnetic fields such as mobile phones, mobile phone base stations, mobile phone jammers, radar systems, magnetic resonance imaging (MRI) systems and dentistry cavitrons over the past years. In this article, recent studies on the biological effects of non-ionizing electromagnetic radiation in the range of radiofrequency (RF) on some important features of stem cells such as their proliferation and differentiation are reviewed. Studies reviewed in this paper indicate that the stimulatory or inhibitory effects of RF radiation on the proliferation and differentiation of stem cells depend on various factors such as the biological systems, experiment conditions, the frequency and intensity of RF and the duration of exposure.

  6. Simplified segmented human models for whole body and localised SAR evaluation of 20 MHz to 6 GHz electromagnetic field exposures.

    Science.gov (United States)

    Wu, Tongning; Shao, Qing; Yang, Lei

    2013-03-01

    The digital human model is a key element in evaluating the electromagnetic field (EMF) exposure. This paper proposes the application of simplified segmented human models for EMF exposure compliance evaluation with the whole body and the localised limits. The method is based on the fact that most of the EMF power absorption is concentrated in several major tissues. Two kinds of human models were simply (the proposed method) and precisely segmented from two sets of whole body magnetic resonance imaging (MRI) scanned images. The whole body average-specific absorption rate (WBA-SAR) and the peak localised SAR averaging over 10 g tissues for the two kinds of models are calculated for various exposure configurations. The results confirmed the efficiency and the validity of the proposed method. The application as evaluating the MRI radiofrequency EMF exposure is also discussed in the paper.

  7. Simplified segmented human models for whole body and localised SAR evaluation of 20 MHz to 6 GHz electromagnetic field exposures

    International Nuclear Information System (INIS)

    Wu, T.; Shao, Q.; Yang, L.

    2013-01-01

    The digital human model is a key element in evaluating the electromagnetic field (EMF) exposure. This paper proposes the application of simplified segmented human models for EMF exposure compliance evaluation with the whole body and the localised limits. The method is based on the fact that most of the EMF power absorption is concentrated in several major tissues. Two kinds of human models were simply (the proposed method) and precisely segmented from two sets of whole body magnetic resonance imaging (MRI) scanned images. The whole body average-specific absorption rate (WBA-SAR) and the peak localised SAR averaging over 10 g tissues for the two kinds of models are calculated for various exposure configurations. The results confirmed the efficiency and the validity of the proposed method. The application as evaluating the MRI radiofrequency EMF exposure is also discussed in the paper. (authors)

  8. Effects of heating with radiofrequency power on myocardial impulse conduction: is radiofrequency ablation exclusively thermally mediated?

    NARCIS (Netherlands)

    Simmers, T. A.; de Bakker, J. M.; Wittkampf, F. H.; Hauer, R. N.

    1996-01-01

    Although it is generally accepted that radiofrequency (RF) ablation causes exclusively thermally mediated effects, it has never been proved. In a previous report, temperatures required to induce conduction block in superfused canine epicardial ventricular myocardium were identified by exposure to

  9. Technical basis for evaluating electromagnetic and radio-frequency interference in safety-related I ampersand C systems

    International Nuclear Information System (INIS)

    Ewing, P.D.; Korsah, K.

    1994-04-01

    This report discusses the development of the technical basis for the control of upsets and malfunctions in safety-related instrumentation and control (I ampersand C) systems caused by electromagnetic and radio-frequency interference (EMI/RFI) and power surges. The research was performed at the Oak Ridge National Laboratory (ORNL) and was sponsored by the USNRC Office of Nuclear Regulatory Research (RES). The motivation for research stems from the safety-related issues that need to be addressed with the application of advanced I ampersand C systems to nuclear power plants. Development of the technical basis centered around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems known to be the source(s) of EMI/RFI and power surges. First, good EMC design and installation practices need to be established to control the impact of interference sources on nearby circuits and systems. These EMC good practices include circuit layouts, terminations, filtering, grounding, bonding, shielding, and adequate physical separation. Second, an EMI/RFI test and evaluation program needs to be established to outline the tests to be performed, the associated test methods to be followed, and carefully formulated acceptance criteria based on the intended environment to ensure that the circuit or system under test meets the recommended guidelines. Third, a program needs to be developed to perform confirmatory tests and evaluate the surge withstand capability (SWC) and of I ampersand C equipment connected to or installed in the vicinity of power circuits within the nuclear power plant. By following these three steps, the design and operability of safety-related I ampersand C systems against EMI/RFI and power surges can be evaluated, acceptance criteria can be developed, and appropriate regulatory guidance can be provided

  10. Pretreatment Evaluation with Contrast-Enhanced Ultrasonography for Percutaneous Radiofrequency Ablation of Hepatocellular Carcinomas with Poor Conspicuity on Conventional Ultrasonography

    International Nuclear Information System (INIS)

    Kim, Ah Yeong; Lee, Min Woo; Rhim, Hyunchul; Cha, Dong Ik; Choi, Dongil; Kim, Young-sun; Lim, Hyo Keun; Cho, Seong Whi

    2013-01-01

    To determine whether pretreatment evaluation with contrast-enhanced ultrasonography (CEUS) is effective for percutaneous radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) with poor conspicuity on conventional ultrasonography (US). This retrospective study was approved by the institutional review board and informed consent was waived. From June 2008 to July 2011, 82 patients having HCCs (1.2 ± 0.4 cm) with poor conspicuity on planning US for RFA were evaluated with CEUS prior to percutaneous RFA. We analyzed our database, radiologic reports, and US images in order to determine whether the location of HCC candidates on planning US coincide with that on CEUS. To avoid incomplete ablation, percutaneous RFA was performed only when HCC nodules were identified on CEUS. The rate of technical success was assessed. The cumulative rate of local tumor progression was estimated with the use of the Kaplan-Meier method (mean follow-up: 24.0 ± 13.0 months). Among 82 patients, 73 (89%) HCCs were identified on CEUS, whereas 9 (11%) were not. Of 73 identifiable HCCs on CEUS, the location of HCC on planning US corresponded with that on CEUS in 64 (87.7%), whereas the location did not correspond in 9 (12.3%) HCCs. Technical success was achieved for all 73 identifiable HCCs on CEUS in a single (n = 72) or two (n = 1) RFA sessions. Cumulative rates of local tumor progression were estimated as 1.9% and 15.4% at 1 and 3 years, respectively. Pretreatment evaluation with CEUS is effective for percutaneous RFA of HCCs with poor conspicuity on conventional US

  11. Neuroprotective Effect of Ginseng against Alteration of Calcium Binding Proteins Immunoreactivity in the Mice Hippocampus after Radiofrequency Exposure

    Directory of Open Access Journals (Sweden)

    Dhiraj Maskey

    2013-01-01

    Full Text Available Calcium binding proteins (CaBPs such as calbindin D28-k, parvalbumin, and calretinin are able to bind Ca2+ with high affinity. Changes in Ca2+ concentrations via CaBPs can disturb Ca2+ homeostasis. Brain damage can be induced by the prolonged electromagnetic field (EMF exposure with loss of interacellular Ca2+ balance. The present study investigated the radioprotective effect of ginseng in regard to CaBPs immunoreactivity (IR in the hippocampus through immunohistochemistry after one-month exposure at 1.6 SAR value by comparing sham control with exposed and ginseng-treated exposed groups separately. Loss of dendritic arborization was noted with the CaBPs in the Cornu Ammonis areas as well as a decrease of staining intensity of the granule cells in the dentate gyrus after exposure while no loss was observed in the ginseng-treated group. A significant difference in the relative mean density was noted between control and exposed groups but was nonsignificant in the ginseng-treated group. Decrease in CaBP IR with changes in the neuronal staining as observed in the exposed group would affect the hippocampal trisynaptic circuit by alteration of the Ca2+ concentration which could be prevented by ginseng. Hence, ginseng could contribute as a radioprotective agent against EMF exposure, contributing to the maintenance of Ca2+ homeostasis by preventing impairment of intracellular Ca2+ levels in the hippocampus.

  12. WORKSHOPS: Radiofrequency superconductivity

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    In the continual push towards higher energy particle beams, superconducting radiofrequency techniques now play a vital role, highlighted in the fifth workshop on radiofrequency superconductivity, held at DESY from 19 - 24 August 1991

  13. Klebsiella pneumonia, a Microorganism that Approves the Non-linear Responses to Antibiotics and Window Theory after Exposure to Wi-Fi 2.4 GHz Electromagnetic Radiofrequency Radiation

    Science.gov (United States)

    Taheri, M.; Mortazavi, S. M. J.; Moradi, M.; Mansouri, Sh.; Nouri, F.; Mortazavi, S. A. R.; Bahmanzadegan, F.

    2015-01-01

    Background Drug resistance is widely believed to be an increasingly serious threat to global public health. We have previously reported that short term exposure of microorganisms to diagnostic ultrasound waves could significantly alter their sensitivity to antibiotics. In our previous studies, Klebsiella pneumoniae showed major differences in the sensitivity to antibiotics in exposed and non-exposed samples. This study was aimed at investigating the alteration of antibiotic resistance of Klebsiella pneumonia, after exposure to Wi-Fi 2.4 GHz electromagnetic radiofrequency radiation. Materials and Methods In this in vitro study, three replicate agar plates were used for each test. The antibiotic susceptibility test was carried out using disc diffusion method on Mueller Hinton agar plates and the inhibition zones in both control and exposed groups were measured. A common Wi-Fi router was used in this study as the radiofrequency exposure source. Irradiated samples were exposed to Wi-Fi radiofrequency radiation for 3, 4.5 and 8 hours. Results Statistically significant variations of sensitivity to antibiotics were found for all studied antibiotics after 4.5 hours of RF exposure, compared to non-exposed bacteria. Interestingly, the mean diameters of the inhibition zones after 3 hours of exposure were less than those exposed for 4.5 hours. Following this rise in the sensitivity to antibiotics, a fall was observed in the bacteria exposed for 8 hours for all studied antibiotics. Conclusion The findings of this study show a statistically significant rise in the sensitivity of Klebsiella pneumoniae to different antibiotics after 4.5 hours of exposure to 2.4 GHz Wi-Fi radiation, followed by a fall after 8 hours of exposure. These observations can be interpreted by the concept of non-linearity in the responses of Klebsiella pneumoniae to different antibiotics after exposure to electromagnetic radiofrequency radiation. As in this study a minimum level of effect was needed for the

  14. Klebsiella pneumonia, a Microorganism that Approves the Non-linear Responses to Antibiotics and Window Theory after Exposure to Wi-Fi 2.4 GHz Electromagnetic Radiofrequency Radiation

    Directory of Open Access Journals (Sweden)

    Taheri M.

    2015-09-01

    Full Text Available Background: Drug resistance is widely believed to be an increasingly serious threat to global public health. We have previously reported that short term exposure of microorganisms to diagnostic ultrasound waves could significantly alter their sensitivity to antibiotics. In our previous studies, Klebsiella pneumoniae showed major differences in the sensitivity to antibiotics in exposed and non-exposed samples. This study was aimed at investigating the alteration of antibiotic resistance of Klebsiella pneumonia, after exposure to Wi-Fi 2.4 GHz electromagnetic radiofrequency radiation. Materials and Methods: In this in vitro study, three replicate agar plates were used for each test. The antibiotic susceptibility test was carried out using disc diffusion method on Mueller Hinton agar plates and the inhibition zones in both control and exposed groups were measured. A common Wi-Fi router was used in this study as the radiofrequency exposure source. Irradiated samples were exposed to Wi-Fi radiofrequency radiation for 3, 4.5 and 8 hours. Results: Statistically significant variations of sensitivity to antibiotics were found for all studied antibiotics after 4.5 hours of RF exposure, compared to non-exposed bacteria. Interestingly, the mean diameters of the inhibition zones after 3 hours of exposure were less than those exposed for 4.5 hours. Following this rise in the sensitivity to antibiotics, a fall was observed in the bacteria exposed for 8 hours for all studied antibiotics. Conclusion: The findings of this study show a statistically significant rise in the sensitivity of Klebsiella pneumoniae to different antibiotics after 4.5 hours of exposure to 2.4 GHz Wi-Fi radiation, followed by a fall after 8 hours of exposure. These observations can be interpreted by the concept of non-linearity in the responses of Klebsiella pneumoniae to different antibiotics after exposure to electromagnetic radiofrequency radiation. As in this study a minimum level of

  15. Alteration of glycine receptor immunoreactivity in the auditory brainstem of mice following three months of exposure to radiofrequency radiation at SAR 4.0 W/kg.

    Science.gov (United States)

    Maskey, Dhiraj; Kim, Hyung Gun; Suh, Myung-Whan; Roh, Gu Seob; Kim, Myeung Ju

    2014-08-01

    The increasing use of mobile communication has triggered an interest in its possible effects on the regulation of neurotransmitter signals. Due to the close proximity of mobile phones to hearing-related brain regions during usage, its use may lead to a decrease in the ability to segregate sounds, leading to serious auditory dysfunction caused by the prolonged exposure to radiofrequency (RF) radiation. The interplay among auditory processing, excitation and inhibitory molecule interactions plays a major role in auditory function. In particular, inhibitory molecules, such a glycine, are predominantly localized in the auditory brainstem. However, the effects of exposure to RF radiation on auditory function have not been reported to date. Thus, the aim of the present study was to investigate the effects of exposure to RF radiation on glycine receptor (GlyR) immunoreactivity (IR) in the auditory brainstem region at 835 MHz with a specific absorption rate of 4.0 W/kg for three months using free-floating immunohistochemistry. Compared with the sham control (SC) group, a significant loss of staining intensity of neuropils and cells in the different subdivisions of the auditory brainstem regions was observed in the mice exposed to RF radiation (E4 group). A decrease in the number of GlyR immunoreactive cells was also noted in the cochlear nuclear complex [anteroventral cochlear nucleus (AVCN), 31.09%; dorsal cochlear nucleus (DCN), 14.08%; posteroventral cochlear nucleus (PVCN), 32.79%] and the superior olivary complex (SOC) [lateral superior olivary nucleus (LSO), 36.85%; superior paraolivary nucleus (SPN), 24.33%, medial superior olivary nucleus (MSO), 23.23%; medial nucleus of the trapezoid body (MNTB), 10.15%] of the mice in the E4 group. Auditory brainstem response (ABR) analysis also revealed a significant threshold elevation of in the exposed (E4) group, which may be associated with auditory dysfunction. The present study suggests that the auditory brainstem region

  16. Evaluation of hepatocellular carcinoma tumor vascularity using contrast-enhanced ultrasonography as a predictor for local recurrence following radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Tomohiro [Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024 (Japan); Numata, Kazushi, E-mail: kz-numa@urahp.yokohama-cu.ac.jp [Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024 (Japan); Hao, Yoshiteru; Doba, Nobutaka; Hara, Koji [Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024 (Japan); Kondo, Masaaki [Division of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004 (Japan); Tanaka, Katsuaki [Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024 (Japan); Maeda, Shin [Division of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004 (Japan)

    2017-04-15

    Purpose: The purpose of this study was to evaluate whether the hypervascularity of hepatocellular carcinomas (HCCs) on contrast-enhanced ultrasonography (CEUS) prior to radiofrequency ablation (RFA) is a significant risk factor for local recurrence after RFA. Materials and methods: Institutional review board approval and informed consent were obtained. Overall, 208 patients (mean age, 71.7 years; range, 50–87 years; 137 men, 71 women) with 282 HCCs treated with RFA were analyzed retrospectively. The mean maximum tumor diameter was 15.7 mm. We compared the abilities of CEUS and contrast-enhanced computed tomography (CECT) to detect hypervascularity in HCCs. We then classified the HCCs into two groups according to the arterial-phase CEUS findings: a “hypervascular group” with whole or partial hypervascular areas within the lesions compared with the surrounding liver parenchyma, and a “non-hypervascular group” with isovascular or hypovascular areas within the lesions. We assessed the cumulative rate of local recurrence after RFA, and we also evaluated the risk factors for local recurrence using a univariate analysis. Results: The detection rate for hypervascular HCCs was significantly higher using CEUS (78%, 221/282) than that using CECT (66%, 186/282) (P < 0.001). Using the CEUS findings, the cumulative rate of local recurrence was significantly higher in the hypervascular group (41.2%, 56/221) than in the non-hypervascular group (18.4%, 6/61) (P = 0.007). A univariate analysis revealed that hypervascularity on CEUS was an independent risk factor for local recurrence (P = 0.010). Conclusion: Hypervascularity in HCCs as observed using CEUS is a significant risk factor for local recurrence after RFA.

  17. Environmental Radiofrequency Electromagnetic Fields Exposure at Home, Mobile and Cordless Phone Use, and Sleep Problems in 7-Year-Old Children

    NARCIS (Netherlands)

    Huss, Anke; van Eijsden, Manon; Guxens, Monica; Beekhuizen, Johan; van Strien, Rob; Kromhout, Hans; Vrijkotte, Tania; Vermeulen, Roel

    2015-01-01

    We evaluated if exposure to RF-EMF was associated with reported quality of sleep in 2,361 children, aged 7 years. This study was embedded in the Amsterdam Born Children and their Development (ABCD) birth cohort study. When children were about five years old, school and residential exposure to RF-EMF

  18. Avaliação da propagação de sinais de radiofrequência para tecnologia Zigbee em granja de frango de corte Evaluation of radiofrequency signals for Zigbee technology in poultry housing

    Directory of Open Access Journals (Sweden)

    Eduardo F. Nunes

    2011-01-01

    Full Text Available Visou-se, neste trabalho, realizar a predição de sinais de radiofrequência para a aplicação de Rede de Sensores Sem Fio (RSSF de monitoramento e controle em uma granja de frango de corte. A tecnologia de comunicação sem fio utilizada foi a Zigbee, com o padrão IEEE 802.15.4 compondo a camada física e de enlace. Desenvolveu-se, para automatizar a leitura de potências, um aplicativo em linguagem Delphi e, para a predição de sinais de RF (Radiofrequência, utilizou-se o modelo Shadowing adaptado. Todos os testes foram realizados em granja comercial, no Município de Tuiuti, estado de São Paulo, Brasil. Os resultados obtidos demonstraram boas condições de transmissão até 131 m, indicando que a tecnologia Zigbee é adequada, segundo a perspectiva de propagação de sinais, para a implementação de RSSF em granjas de frango de corte.This study aimed to conduct an evaluation for the implementation of Wireless Sensors Network (WSN of tracking and control in a poultry farm. The wireless technology used was Zigbee, with the IEEE 802.15.4 standard forming the physical layer and link layer. To automate the power measurement a DELPHI language software was developed and, for the prediction of RF signals, an adjusted model of the shadowing was used. All tests were performed in a commercial broiler farm, in the city of Tuiuti in the State of São Paulo, Brazil. The results of this study indicate that Zigbee technology is appropriate, from the perspective of signal propagation, to implement WSN in poultry housing.

  19. Information exposure, opportunity evaluation and entrepreneurial action

    DEFF Research Database (Denmark)

    Autio, E.; Dahlander, L.; Frederiksen, Lars

    2013-01-01

    information shaped opportunity evaluation, and social information about user needs drove individuals to entrepreneurial action. Our empirical findings suggest that reducing demand uncertainty is a central factor regulating of entrepreneurial action, an insight that received theories of entrepreneurial action......We study how an individual's exposure to external information regulates the evaluation of entrepreneurial opportunities and entrepreneurial action. Combining data from interviews, a survey, and a comprehensive web log of an online user community spanning eight years, we find that technical...

  20. Subjective and objective parameters in the evaluation of radiofrequency ablation of the inferior turbinate do not correlate: A pilot study.

    Science.gov (United States)

    Tomazic, Peter Valentin; Gerstenberger, Claus; Rant, Bettina; Nemetz, Ulrike; Brezjak-Kahlert, Christiana; Wolf, Axel; Freudenschuss, Kurt; Wolf, Gerald

    2016-08-01

    Inferior turbinate hypertrophy is a common cause of nasal obstruction. We conducted a prospective study to correlate subjective and objective parameters in assessing the effectiveness of radiofrequency ablation (RFA). Our initial study population was made up of 10 patients who presented with nasal obstruction; 1 patient was lost to follow-up, leaving us with 7 women and 2 men, aged 26 to 65 years (mean: 37.9 ± 12.8), and 16 turbinates (7 bilateral, 1 right, and 1 left). Visual analogue scale (VAS) scores, Nasal Obstruction and Symptom Evaluation (NOSE) questionnaire scores, rhinomanometry results, and CT- and MRI-based volumetry were obtained before RFA and 6 months afterward. For the subjective parameters, the mean pre- and postoperative VAS scores for the 16 turbinates were 6.6 ± 1.6 and 2.8 ± 2.0 (p < 0.001), respectively, and the mean pre- and postoperative NOSE scores in the 9 patients were 15.3 ± 3.1 and 5.8 ± 5.4 (p = 0.003). For the objective parameters, the mean pre- and postoperative rhinomanometry values at 150 Pa were 241.0 ± 141.3 and 265.4 ± 157.3 ml/sec (p = 0.403), and the mean pre- and postoperative volumetry values were 5.3 ± 2.5 and 5.0 ± 2.1 cm(3) (p = 0.551). Note that only the differences in the subjective parameters reached statistical significance. RFA of the inferior turbinates as a treatment for nasal obstruction is safe and easy. However, our study found a discrepancy between the subjective and objective outcomes parameters, as the former showed highly significant improvement and the latter showed only a slight improvement that did not reach statistical significance.

  1. Novel high-resolution temperature probe for radiofrequency dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Schuderer, Juergen [Foundation for Research on Information Technologies in Society (IT' IS), Integrated Systems Laboratory IIS, Swiss Federal Institute of Technology (ETH), CH-8092 Zurich (Switzerland); Schmid, Thomas [Schmid and Partner Engineering AG, 8004 Zurich (Switzerland); Urban, Gerald [IMTEK, Albert-Ludwigs University Freiburg, 79110 Freiburg (Germany); Samaras, Theodoros [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Kuster, Niels [Foundation for Research on Information Technologies in Society (IT' IS), Integrated Systems Laboratory IIS, Swiss Federal Institute of Technology (ETH), CH-8092 Zurich (Switzerland)

    2004-03-21

    A novel integrated thermistor probe for temperature evaluations in radiofrequency-heated environments was realized. The probe's sensitive area is based on a highly resistive 50 {mu}m x 100 {mu}m layer of amorphous germanium processed on a glass tip. The small dimensions allow measurements with a distance as close as 150 {mu}m from solid boundaries. Due to its high temperature resolution of 4 mK and its short response time of the order of 10 ms, the sensor is very well suited for dosimetric measurements in strong absorption gradients. The influence of radiofrequency (RF) electric fields on the signal is minimized due to the high resistance of the sensor and the leads. The probe was successfully used to determine the highly nonuniform absorption distribution resulting from the RF exposure of cell cultures placed in Petri dishes. (note)

  2. Analgesia produced by exposure to 2450-MHz radiofrequency radiation (RFR) is mediated by brain mu- and kappa-opioid receptors

    Energy Technology Data Exchange (ETDEWEB)

    Salomon, G.; Park, E.J.; Quock, R.M. (Univ. of Illinois, Rockford (United States))

    1992-02-26

    This study was conducted to identify the opioid receptor subtype(s) responsible for RFR-induced analgesia. Male Swiss Webster mice, 20-25 g, were exposed to 20 mW/cm{sup 2} RFR in a 2,450-MHz waveguide system for 10 min, then tested 15 min later in the abdominal constriction paradigm which detects {mu}- and {kappa}-opioid activity. Immediately following RFR exposure, different groups of mice were pretreated intracerebroventricularly with different opioid receptor blockers with selectivity for {mu}- or {kappa}-opioid receptors. Results show that RFR-induced analgesia was attenuated by higher but not lower doses of the non-selective antagonist naloxone, but the selective {mu}-opioid antagonist {beta}-funaltrexamine and by the selective {kappa}-opioid antagonist norbinaltorphimine. RFR-induced analgesia was also reduced by subcutaneous pretreatment with 5.0 mg/kg of the {mu}-/{kappa}-opioid antagonist({minus})-5,9-diethyl-{alpha}-5,9-dialkyl-2{prime}-hydroxy-6,7-benzomorphan(MR-2266). These findings suggest that RFR-induced analgesia may be mediated by both {mu}- and {kappa}-opioid mechanisms.

  3. Revision of NATO standardization agreement (STANAG) 2345 'Evaluation and control of personnel exposure to radio frequency fields'

    International Nuclear Information System (INIS)

    Klauenberg, B.J.; Merritt, J.H.; Gardner, R.

    1996-01-01

    North Atlantic Treaty Organization (NATO) joint operations, which reach across borders of countries that have different standards, could present a logistical nightmare were it not for standardization agreements, called STANAGs. STANAGs are established to provide uniform policies and procedures to insure international cooperation and to maintain the most effective levels of commonalty, compatibility, interchange-ability and inter-operability in military operations. Since signals produced by radar and communications equipment are not contained by national boundaries, a STANAG for Radiofrequency Radiation (RFR) is essential. The STANAG-2345 Control and Evaluation of Personnel Exposure to Radio Frequency Radiation. establishes criteria for the evaluation and control of personnel exposure to radio-frequency radiation within NATO forces. It defines hazard assessment, allows for control measures, indicates actions in case of accidental overexposures and establishes permissible exposure limits. The promulgation of this STANAG in 1979 was the culmination of deliberations among scientists and health professionals within the NATO community that began in May 1973. At the time of adoption it contained guidance based on the then state-of-knowledge. The standard has not been updated since it was issued, despite great advances in the knowledge-base defining health and safety aspects of RFR. Several standards setting groups recently updated their standards, including the American National Standards Institute revised safety guidance for RFR. This has left a large technology gap between the newer standards and STANAG 2345. (author)

  4. MR evaluation of pulmonary vein diameter reduction after radiofrequency catheter ablation of atrial fibrillation

    Energy Technology Data Exchange (ETDEWEB)

    Anselme, Frederic; Savoure, Arnaud; Mabru, Mikael; Cribier, Alain [Rouen University Hospital, Department of Cardiology, Rouen (France); Gahide, Gerald [Rouen University Hospital, Department of Radiology and Laboratoire QuantIF, Rouen (France); Gerbaud, Edouard [Rouen University Hospital, Department of Cardiology, Rouen (France); Rouen University Hospital, Department of Radiology and Laboratoire QuantIF, Rouen (France); Dacher, Jean-Nicolas [Rouen University Hospital, Department of Radiology and Laboratoire QuantIF, Rouen (France); University Hospital, Department of Radiology, Rouen, Cedex (France)

    2006-11-15

    Fifty consecutive patients aged 52{+-}12 years suffering from drug refractory atrial fibrillation (AF) underwent baseline and post-ablation MR angiography (MRA) at a mean follow-up of 4{+-}3.5 months. Pulmonary vein (PV) disconnection was performed with a maximum energy delivery of 30 W. MRA allowed a two-plane measurement of each PV ostium. After ablation, no significant stenosis was observed, and only 1/194 (0.5%) and 3/194 (2%) PVs had a diameter reduction of 31-40% in the coronal and axial planes, respectively. There was a significant overall post-procedural PV narrowing of 4.9% in the coronal plane and 6.5% in the axial plane (P=ns between both planes). MRA is an efficient technique that can be used in pre- and postoperative evaluation of AF patients. Using a maximal power delivery limited to 30 W, no significant PV stenosis was observed at mid-term follow-up. Late PV anatomical assessment is needed to confirm these results on long-term follow-up. (orig.)

  5. Level of Radiofrequency (RF) Radiations from GSM Base Stations ...

    African Journals Online (AJOL)

    Levels of radiofrequency radiations around two global systems for mobile communication (GSM) base stations located in the vicinity of a residential quarter and workplace complex were measured. The effects of the radiofrequency radiations on albino mice placed in exposure cages and located around the base stations ...

  6. HANFORD CHEMICAL VAPORS WORKER CONCERNS & EXPOSURE EVALUATION

    Energy Technology Data Exchange (ETDEWEB)

    ANDERSON, T.J.

    2006-12-20

    Chemical vapor emissions from underground hazardous waste storage tanks on the Hanford site in eastern Washington State are a potential concern because workers enter the tank farms on a regular basis for waste retrievals, equipment maintenance, and surveillance. Tank farm contractors are in the process of retrieving all remaining waste from aging single-shell tanks, some of which date to World War II, and transferring it to newer double-shell tanks. During the waste retrieval process, tank farm workers are potentially exposed to fugitive chemical vapors that can escape from tank headspaces and other emission points. The tanks are known to hold more than 1,500 different species of chemicals, in addition to radionuclides. Exposure assessments have fully characterized the hazards from chemical vapors in half of the tank farms. Extensive sampling and analysis has been done to characterize the chemical properties of hazardous waste and to evaluate potential health hazards of vapors at the ground surface, where workers perform maintenance and waste transfer activities. Worker concerns. risk communication, and exposure assessment are discussed, including evaluation of the potential hazards of complex mixtures of chemical vapors. Concentrations of vapors above occupational exposure limits-(OEL) were detected only at exhaust stacks and passive breather filter outlets. Beyond five feet from the sources, vapors disperse rapidly. No vapors have been measured above 50% of their OELs more than five feet from the source. Vapor controls are focused on limited hazard zones around sources. Further evaluations of vapors include analysis of routes of exposure and thorough analysis of nuisance odors.

  7. Efficacy evaluation of laparoscopy assisted ultrasound guided radiofrequency ablation in the treatment of hepatocellular carcinoma beneath the diaphragm

    Directory of Open Access Journals (Sweden)

    Song WANG

    2017-06-01

    Full Text Available Objective To explore the feasibility, safety and efficacy of laparoscopy assisted ultrasound guided radiofrequency ablation (RFA in the treatment of hepatocellular carcinoma (HCC beneath the diaphragm. Methods Twenty- three consecutive patients with solitary HCC beneath the diaphragm were treated by laparoscopy assisted ultrasound guided RFA in the Chinese PLA General Hospital from January 2013 to March 2016. We observed the perioperative complications and followed- up long-term effect. Results All the 23 patients successfully underwent laparoscopy assisted ultrasound guided radiofrequency ablation. No serious complications such as massive hemorrhage, biliary fistula and severe pleural effusion, hemopneumothorax occurred in the patients during perioperative period. CT examination 2-3 days after the operation revealed that the tumor was completely covered by the ablation area. Besides, the survival condition was satisfactory during follow-up period of 9-38 months. Conclusion Laparoscopy-assisted ultrasound-guided radiofrequency ablation is effective and safe for HCC beneath the diaphragm. DOI: 10.11855/j.issn.0577-7402.2017.05.16

  8. Evaluation of the intraoperative trauma degree and postoperative speech function of low-temperature plasma radiofrequency surgery treatment of children with OSAHS

    Directory of Open Access Journals (Sweden)

    He Liu

    2017-05-01

    Full Text Available Objective: To evaluate the intraoperative trauma degree and postoperative speech function of low-temperature plasma radiofrequency surgery treatment of children with obstructive sleep apnea hypopnea syndrome (OSAHS. Methods: A total of 118 children with OSAHS were divided into the control group (n=59 who received general surgery and the observation group (n=59 who received the low-temperature plasma radiofrequency surgery according to the random number table. Before operation and 24 h after operation, serum levels of stress hormones, acute phase proteins and inflammatory markers of two groups of children were determined, and the speech function parameter levels were assessed. Results: Before operation, differences in serum contents of stress hormones, acute phase proteins and inflammatory factors as well as speech function parameter levels were not statistically significant between two groups of patients. 24 h after operation, serum stress hormones adrenocorticotropic hormone (ACTH, angiotensin-2 (Ang-2, norepinephrine (NE, cortisol (Cor contents of observation group were lower than those of control group, serum acute phase proteins haptoglobin (HP, ceruloplasmin (CER, and prealbumin (PA contents were lower than those of control group, and serum inflammatory factors interleukin-1 (IL-1, interleukin-4 (IL-4, interleukin-27 (IL-27, tumor necrosis factor α(TNF-α contents were lower than those of control group; speech function parameters NNE and NHR levels of observation group were higher than those of control group. Conclusion: Compared with routine surgery, lowtemperature plasma radiofrequency surgery treatment of children with OSAHS causes less surgical trauma and more greatly improves the postoperative speech level.

  9. Environmental Radiofrequency Electromagnetic Fields Exposure at Home, Mobile and Cordless Phone Use, and Sleep Problems in 7-Year-Old Children

    NARCIS (Netherlands)

    Huss, Anke; van Eijsden, Manon; Guxens, Monica; Beekhuizen, Johan; van Strien, Rob; Kromhout, Hans; Vrijkotte, Tania; Vermeulen, Roel

    2015-01-01

    BACKGROUND: We evaluated if exposure to RF-EMF was associated with reported quality of sleep in 2,361 children, aged 7 years. METHODS: This study was embedded in the Amsterdam Born Children and their Development (ABCD) birth cohort study. When children were about five years old, school and

  10. Environmental Radiofrequency Electromagnetic Fields Exposure at Home, Mobile and Cordless Phone Use, and Sleep Problems in 7-Year-Old Children.

    Directory of Open Access Journals (Sweden)

    Anke Huss

    Full Text Available We evaluated if exposure to RF-EMF was associated with reported quality of sleep in 2,361 children, aged 7 years.This study was embedded in the Amsterdam Born Children and their Development (ABCD birth cohort study. When children were about five years old, school and residential exposure to RF-EMF from base stations was assessed with a geospatial model (NISMap and from indoor sources (cordless phone/WiFi using parental self-reports. Parents also reported their children's use of mobile or cordless phones. When children were seven years old, we evaluated sleep quality as measured with the Child Sleep Habits Questionnaire (CSHQ filled in by parents. Of eight CSHQ subscales, we evaluated sleep onset delay, sleep duration, night wakenings, parasomnias and daytime sleepiness with logistic or negative binomial regression models, adjusting for child's age and sex and indicators of socio-economic position of the parents. We evaluated the remaining three subscales (bedtime resistance, sleep anxiety, sleep disordered breathing as unrelated outcomes (negative control because these were a priori hypothesised not to be associated with RF-EMF.Sleep onset delay, night wakenings, parasomnias and daytime sleepiness were not associated with residential exposure to RF-EMF from base stations. Sleep duration scores were associated with RF-EMF levels from base stations. Higher use mobile phones was associated with less favourable sleep duration, night wakenings and parasomnias, and also with bedtime resistance. Cordless phone use was not related to any of the sleeping scores.Given the different results across the evaluated RF-EMF exposure sources and the observed association between mobile phone use and the negative control sleep scale, our study does not support the hypothesis that it is the exposure to RF-EMF that is detrimental to sleep quality in 7-year old children, but potentially other factors that are related to mobile phone usage.

  11. Environmental Radiofrequency Electromagnetic Fields Exposure at Home, Mobile and Cordless Phone Use, and Sleep Problems in 7-Year-Old Children.

    Science.gov (United States)

    Huss, Anke; van Eijsden, Manon; Guxens, Monica; Beekhuizen, Johan; van Strien, Rob; Kromhout, Hans; Vrijkotte, Tania; Vermeulen, Roel

    2015-01-01

    We evaluated if exposure to RF-EMF was associated with reported quality of sleep in 2,361 children, aged 7 years. This study was embedded in the Amsterdam Born Children and their Development (ABCD) birth cohort study. When children were about five years old, school and residential exposure to RF-EMF from base stations was assessed with a geospatial model (NISMap) and from indoor sources (cordless phone/WiFi) using parental self-reports. Parents also reported their children's use of mobile or cordless phones. When children were seven years old, we evaluated sleep quality as measured with the Child Sleep Habits Questionnaire (CSHQ) filled in by parents. Of eight CSHQ subscales, we evaluated sleep onset delay, sleep duration, night wakenings, parasomnias and daytime sleepiness with logistic or negative binomial regression models, adjusting for child's age and sex and indicators of socio-economic position of the parents. We evaluated the remaining three subscales (bedtime resistance, sleep anxiety, sleep disordered breathing) as unrelated outcomes (negative control) because these were a priori hypothesised not to be associated with RF-EMF. Sleep onset delay, night wakenings, parasomnias and daytime sleepiness were not associated with residential exposure to RF-EMF from base stations. Sleep duration scores were associated with RF-EMF levels from base stations. Higher use mobile phones was associated with less favourable sleep duration, night wakenings and parasomnias, and also with bedtime resistance. Cordless phone use was not related to any of the sleeping scores. Given the different results across the evaluated RF-EMF exposure sources and the observed association between mobile phone use and the negative control sleep scale, our study does not support the hypothesis that it is the exposure to RF-EMF that is detrimental to sleep quality in 7-year old children, but potentially other factors that are related to mobile phone usage.

  12. Environmental Radiofrequency Electromagnetic Fields Exposure at Home, Mobile and Cordless Phone Use, and Sleep Problems in 7-Year-Old Children

    Science.gov (United States)

    Huss, Anke; van Eijsden, Manon; Guxens, Monica; Beekhuizen, Johan; van Strien, Rob; Kromhout, Hans; Vrijkotte, Tania; Vermeulen, Roel

    2015-01-01

    Background We evaluated if exposure to RF-EMF was associated with reported quality of sleep in 2,361 children, aged 7 years. Methods This study was embedded in the Amsterdam Born Children and their Development (ABCD) birth cohort study. When children were about five years old, school and residential exposure to RF-EMF from base stations was assessed with a geospatial model (NISMap) and from indoor sources (cordless phone/WiFi) using parental self-reports. Parents also reported their children’s use of mobile or cordless phones. When children were seven years old, we evaluated sleep quality as measured with the Child Sleep Habits Questionnaire (CSHQ) filled in by parents. Of eight CSHQ subscales, we evaluated sleep onset delay, sleep duration, night wakenings, parasomnias and daytime sleepiness with logistic or negative binomial regression models, adjusting for child’s age and sex and indicators of socio-economic position of the parents. We evaluated the remaining three subscales (bedtime resistance, sleep anxiety, sleep disordered breathing) as unrelated outcomes (negative control) because these were a priori hypothesised not to be associated with RF-EMF. Results Sleep onset delay, night wakenings, parasomnias and daytime sleepiness were not associated with residential exposure to RF-EMF from base stations. Sleep duration scores were associated with RF-EMF levels from base stations. Higher use mobile phones was associated with less favourable sleep duration, night wakenings and parasomnias, and also with bedtime resistance. Cordless phone use was not related to any of the sleeping scores. Conclusion Given the different results across the evaluated RF-EMF exposure sources and the observed association between mobile phone use and the negative control sleep scale, our study does not support the hypothesis that it is the exposure to RF-EMF that is detrimental to sleep quality in 7-year old children, but potentially other factors that are related to mobile phone

  13. Comparative study to evaluate the efficacy of radiofrequency ablation versus trichloroacetic acid in the treatment of xanthelasma palpebrarum

    Directory of Open Access Journals (Sweden)

    Praveen Kumar Shanmugam Reddy

    2016-01-01

    Full Text Available Background: Xanthelasma palpebrarum (XP is a metabolic disorder involving the eyelids. Radiofrequency(RF surgery and trichloroacetic acid (TCA applications have been listed among the procedures for XP, but comparative studies are not available. Aim: To compare the efficacy of radiofrequency surgery versus trichloroacetic acid application in the treatment of XP. Settings and Design: 20 consecutive cases of XP attending dermatology, medicine and endocrinology out-patient departments of M.S.Ramaiah teaching hospital were enrolled for the study. It was an open-label clinical trial conducted in our hospital for a duration of 1 year. Materials and Methods: 20 consecutive patients conforming to inclusion criteria were selected for the study. For each patient, lesions were treated with radiofrequency ablation on one side and TCA application on the other side. Results: RF ablation was done for 12 patients over right eye lesions and 8 patients over the left eye lesions. TCA applications were done for 8 patients over right eye lesions and 12 patients over left eye lesions. 70% of lesions treated with RF ablation had a score of improvement of 4 and 70% of lesions treated with TCA application had a score of improvement of 4, at 4 weeks of follow-up. At four weeks of follow-up 40% in RF group and 15% in TCA group had scarring and 45% in RF group and 30% in TCA group had pigmentation. Conclusion: RF ablation as compared to TCA application, required fewer sessions for achieving more than 75% clearance of lesions. However, TCA applications were associated with fewer complications comparatively.

  14. Interactions between radiofrequency signals and living organisms

    International Nuclear Information System (INIS)

    Boudin, F.; Hours, M.; Lacronique, J.F.; Conil, E.; Hadjem, A.; El Habachi, A.; Wiart, K.; Mann, S.; Kundi, M.; Marc-Vergnes, J.P.; Roosli, M.; Mohler, E.; Frei, P.; Davis, Ch.C.; Balzano, Q.; Ait-Aissa, S.; Billaudel, B.; Poulletier De Gannes, F.; Hurtier, A.; Haro, E.; Taxile, M.; Veyret, B.; Lagroye, I.; Ait-Aissa, S.; Poulletier De Gannes, F.; Athane, A.; Veyret, B.; Lagroye, I.; Yardin, C.; Perrin, A.; Freire, M.; Bachelet, Ch.; Collin, A.; Pla, S.; Debouzy, J.C.; Leveque, Ph.; Van Nierop, L.E.; Huss, A.; Roosli, M.; Egger, M.; Calvez, M.; Salomon, D.

    2010-01-01

    This dossier is composed of 13 articles dealing with the interactions between radio-frequencies and living organisms. It is an overview of various scientific approaches to the field and is of interest for all citizens as the use of mobile phones is widely spread. In the first article it is shown how a model has been built to assess the distribution of the whole body exposure of the population. The second article reviews the state of the art in personal exposure measurements at radio-frequencies. The third article shows that the knowledge of the mechanism of action by which exposure increases the risk of health hazards is necessary. The fourth article shows that individual neuro-psychic factors take a prominent but maybe not unique, part in electromagnetic hypersensitivity. The fifth article shows that no evidence was found to link health disturbances of electromagnetic hypersensitive individuals with radiofrequency exposure. The sixth article shows that the wireless phone is not an athermal hazard to the brain. The seventh article shows that the in utero and post-natal exposure to Wi-Fi does not damage the brains of young rats. The eighth article concludes that recent studies provide no convincing proof of deleterious effects of radiofrequency exposure on the integrity of the blood-brain barrier for specific absorption rates up to 6 W/kg. The ninth article shows that no co-genotoxic effect of radiofrequency was found at levels of exposure that did not induce heating. The tenth article confirms that industry-sponsored studies were least likely to report results suggesting effects. The last article shows that general practitioners are increasingly questioned by their patients about the issue of electromagnetic waves. (A.C.)

  15. Regulations on the limitation of exposure to electrical, magnetic and eletromagneticos fields in the radiofrequencies range between 9 kHz and 300 GHz

    International Nuclear Information System (INIS)

    Martinhao, Maximiliano Salvadori; Silva, Maria Aparecida Muniz Fidelis da; Gontijo, Jose Gustavo Sampaio

    2005-01-01

    The work refers to the known and scientifically proven effects, arising from radiofrequency electromagnetic fields. Accordingly, the regulations on the matter of national telecommunications Agency ANATEL - and the 'state of the art', worldwide, more specifically with regard to the treatment of the issue by the International Telecommunications Union (UIT) and the World Health Organization - OMS. The present work presents the initiatives of ANATEL, for the provision of telecommunications services, using transmitting stations of radiocommunication is performed safely and not detrimental to the population

  16. Synthesis of Bio-Compatible SPION–based Aqueous Ferrofluids and Evaluation of RadioFrequency Power Loss for Magnetic Hyperthermia

    Directory of Open Access Journals (Sweden)

    Sakthikumar D

    2010-01-01

    Full Text Available Abstract Bio-compatible magnetic fluids having high saturation magnetization find immense applications in various biomedical fields. Aqueous ferrofluids of superparamagnetic iron oxide nanoparticles with narrow size distribution, high shelf life and good stability is realized by controlled chemical co-precipitation process. The crystal structure is verified by X-ray diffraction technique. Particle sizes are evaluated by employing Transmission electron microscopy. Room temperature and low-temperature magnetic measurements were carried out with Superconducting Quantum Interference Device. The fluid exhibits good magnetic response even at very high dilution (6.28 mg/cc. This is an advantage for biomedical applications, since only a small amount of iron is to be metabolised by body organs. Magnetic field induced transmission measurements carried out at photon energy of diode laser (670 nm exhibited excellent linear dichroism. Based on the structural and magnetic measurements, the power loss for the magnetic nanoparticles under study is evaluated over a range of radiofrequencies.

  17. Stepwise radiofrequency ablation of Barrett's esophagus preserves esophageal inner diameter, compliance, and motility

    NARCIS (Netherlands)

    Beaumont, H.; Gondrie, J. J.; McMahon, B. P.; Pouw, R. E.; Gregersen, H.; Bergman, J. J.; Boeckxstaens, G. E.

    2009-01-01

    Background and aim: Stepwise endoscopic circumferential and focal radiofrequency ablation is safe and effective for the eradication of Barrett's esophagus. In contrast to other techniques, radiofrequency ablation appears to avoid significant esophageal scarring or stenosis. Our aim was to evaluate

  18. Potential health risks due to telecommunications radiofrequency ...

    African Journals Online (AJOL)

    Background: The global system mobile telecommunications system (GSM) which was recently introduced in Nigeria is now being used by over 40 million people in Nigeria. The use of GSM is accompanied with exposure of the users to radiofrequency radiation (RFR), which if significant, may produce health hazards. This is ...

  19. Assessment of Radiofrequency Power Density Distribution around ...

    African Journals Online (AJOL)

    Background: Global system of mobile communication (GSM) and other telecommunication technologies are now common place in Lagos state Nigeria. The introduction of GSM in 2002 considerably increased radiofrequency (RF) radiation exposure of the public from telecommunications transmitting and receiving antennae ...

  20. Evaluation of ozone exposure indices in exposure-response modeling.

    Science.gov (United States)

    Lee, E H; Tingey, D T; Hogsett, W E

    1988-01-01

    In exposure-response modeling, a major concern is the numerical definition of exposure in relating crop loss to O3, yet few indices have been considered. This paper addresses research in which plant growth was regressed for soybean, wheat, cotton, corn, and sorghum against 613 numerical exposure indices using the Box-Tidwell model. When the minimum sum of squared errors criterion was used, optimum performance was not attained for any single index; however, near optimum performances were achieved by two censored cumulative indices and from a class of indices called the generalized, phenologically weighted, cumulative impact indices (GPWCIs). The top-performing GPWCIs accumulated concentrations, used sigmoid weighting schemes emphasizing O3 concentrations of 0.06 ppm (118 microg m(-3)) or higher, and had phenological weighting schemes with greatest weight occurring 20 to 40 days prior to crop maturity. These findings indicate that (1) peak concentrations are important, but lower concentrations should be included in the calculations, (2) increased plant sensitivity occurs between flowering and maturity, and (3) plants respond to cumulative exposure impact.

  1. Radiofrequency fields associated with the Itron smart meter

    International Nuclear Information System (INIS)

    Tell, R. A.; Sias, G. G.; Vazquez, A.; Sahl, J.; Turman, J. P.; Kavet, R. I.; Mezei, G.

    2008-01-01

    This study examined radiofrequency (RF) emissions from smart electric power meters deployed in two service territories in California for the purpose of evaluating potential human exposure. These meters included transmitters operating in a local area mesh network (RF LAN, ∼250 mW); a cell relay, which uses a wireless wide area network (WWAN, ∼1 W); and a transmitter serving a home area network (HAN, ∼70 mW). In all instances, RF fields were found to comply by a wide margin with the RF exposure limits established by the US Federal Communications Commission. The study included specialised measurement techniques and reported the spatial distribution of the fields near the meters and their duty cycles (typically <1 %) whose value is crucial to assessing time-averaged exposure levels. This study is the first to characterise smart meters as deployed. However, the results are restricted to a single manufacturer's emitters. (authors)

  2. Radiofrequency ablation in dermatology

    Directory of Open Access Journals (Sweden)

    Sachdeva Silonie

    2007-01-01

    Full Text Available Radiofreqeuency ablation is a versatile dermatosurgical procedure used for surgical management of skin lesions by using various forms of alternating current at an ultra high frequency. The major modalities in radiofrequency are electrosection, electrocoagulation, electrodessication and fulguration. The use of radiofrequency ablation in dermatosurgical practice has gained importance in recent years as it can be used to treat most of the skin lesions with ease in less time with clean surgical field due to adequate hemostasis and with minimal side effects and complications. This article focuses on the major tissue effects and factors influencing radiofrequency ablation and its application for various dermatological conditions.

  3. Monopolar radiofrequency ablation using a dual-switching system and a separable clustered electrode: Evaluation of the in vivo efficiency

    International Nuclear Information System (INIS)

    Yoon, Jeong Hee; Lee, Jeong Min; Hwang, Eui Jin; Hwang, In Pyung; Beak, Jee Hyun; Han, Joon Koo; Choi, Byung Ihn

    2014-01-01

    To determine the in vivo efficiency of monopolar radiofrequency ablation (RFA) using a dual-switching (DS) system and a separable clustered (SC) electrode to create coagulation in swine liver. Thirty-three ablation zones were created in nine pigs using a DS system and an SC electrode in the switching monopolar mode. The pigs were divided into two groups for two experiments: 1) preliminary experiments (n = 3) to identify the optimal inter-electrode distances (IEDs) for dual-switching monopolar (DSM)-RFA, and 2) main experiments (n = 6) to compare the in vivo efficiency of DSM-RFA with that of a single-switching monopolar (SSM)-RFA. RF energy was alternatively applied to one of the three electrodes (SSM-RFA) or concurrently applied to a pair of electrodes (DSM-RFA) for 12 minutes in in vivo porcine livers. The delivered RFA energy and the shapes and dimensions of the coagulation areas were compared between the two groups. No pig died during RFA. The ideal IEDs for creating round or oval coagulation area using the DSM-RFA were 2.0 and 2.5 cm. DSM-RFA allowed more efficient RF energy delivery than SSM-RFA at the given time (23.0 ± 4.0 kcal vs. 16.92 ± 2.0 kcal, respectively; p 0.0005). DSM-RFA created a significantly larger coagulation volume than SSM-RFA (40.4 ± 16.4 cm 3 vs. 20.8 ± 10.7 cm 3 ; p < 0.001). Both groups showed similar circularity of the ablation zones (p = 0.29). Dual-switching monopolar-radiofrequency ablation using an SC electrode is feasible and can create larger ablation zones than SSM-RFA as it allows more RF energy delivery at a given time.

  4. Evaluation of the Effect of Radiofrequency Radiation Emitted From Wi-Fi Router and Mobile Phone Simulator on the Antibacterial Susceptibility of Pathogenic Bacteria Listeria monocytogenes and Escherichia coli.

    Science.gov (United States)

    Taheri, M; Mortazavi, S M J; Moradi, M; Mansouri, S; Hatam, G R; Nouri, F

    2017-01-01

    Mobile phones and Wi-Fi radiofrequency radiation are among the main sources of the exposure of the general population to radiofrequency electromagnetic fields (RF-EMF). Previous studies have shown that exposure of microorganisms to RF-EMFs can be associated with a wide spectrum of changes ranged from the modified bacterial growth to the alterations of the pattern of antibiotic resistance. Our laboratory at the nonionizing department of the Ionizing and Non-ionizing Radiation Protection Research Center has performed experiments on the health effects of exposure to animal models and humans to different sources of electromagnetic fields such as cellular phones, mobile base stations, mobile phone jammers, laptop computers, radars, dentistry cavitrons, magnetic resonance imaging, and Helmholtz coils. On the other hand, we have previously studied different aspects of the challenging issue of the ionizing or nonionizing radiation-induced alterations in the susceptibility of microorganisms to antibiotics. In this study, we assessed if the exposure to 900 MHz GSM mobile phone radiation and 2.4 GHz radiofrequency radiation emitted from common Wi-Fi routers alters the susceptibility of microorganisms to different antibiotics. The pure cultures of Listeria monocytogenes and Escherichia coli were exposed to RF-EMFs generated either by a GSM 900 MHz mobile phone simulator and a common 2.4 GHz Wi-Fi router. It is also shown that exposure to RF-EMFs within a narrow level of irradiation (an exposure window) makes microorganisms resistant to antibiotics. This adaptive phenomenon and its potential threats to human health should be further investigated in future experiments. Altogether, the findings of this study showed that exposure to Wi-Fi and RF simulator radiation can significantly alter the inhibition zone diameters and growth rate for L monocytogenes and E coli. These findings may have implications for the management of serious infectious diseases.

  5. Laparoscopic liver resection with radiofrequency.

    Science.gov (United States)

    Croce, E; Olmi, S; Bertolini, A; Erba, L; Magnone, S

    2003-01-01

    In this report, the feasibility, efficacy and safety of laparoscopic liver resection with radiofrequency has been evaluated in a small series of patients. From January 1993 to May 2002 we carried out 7 laparoscopic liver resections (3 men and 4 women), five of which were for benign pathology and two for metastases from colorectal cancer. In four of the above resections we used an argon coagulator; the last three were accomplished by means of a radiofrequency instrument. We had no perioperative or postoperative complications in this small series of patients. There were no deaths. Perioperative blood loss was of 120 mL (range 80-200) and the procedure took about 90 minutes (range 80-110). Hospitalization was of 4 days and pain was adequately controlled by 2 mL of Toradol twice a day. We think that the advantages of laparoscopic techniques together with the efficacy of the radiofrequency instrument in hepatic surgery will allow the diffusion of this method and its extension to safe execution of major resections.

  6. 41 CFR 102-79.90 - What criteria must Executive agencies consider when evaluating antenna siting requests?

    Science.gov (United States)

    2010-07-01

    ... maintenance; (b) Aesthetics; (c) Effects on historic districts, sites, buildings, monuments, structures, or... radiofrequency exposure, ET Docket No. 93-62, entitled “Guidelines for Evaluating the Environmental Effects of Radiofrequency Radiation,” issued August 1, 1996, and any other order on reconsideration relating to...

  7. Letter to the Editor. Comments on Karipidis, K. K., Henderson, A. S., Wijayasinghe, D., Tjong, L. and Tinker, R. Exposure to radiofrequency electromagnetic fields from WiFi in Australian schools. Radiat. Prot. Dosim. 1-8 (2017)

    International Nuclear Information System (INIS)

    Leach, Victor A.; Weller, Steven; Redmayne, Mary

    2017-01-01

    The measurement and collection of radiofrequency (RF) exposure data in Australian classrooms is important and ARPANSA should be applauded for undertaking the much-needed research reported in the above paper. However, the paper presented is very misleading and demonstrates how more care should have been taken when planning and designing the Wi-Fi survey. The survey results presented by Karipidis et al. are of little practical use and are misleading when it comes to determining what RF power density levels are realistically experienced by students in a 'typical' classroom setting. We would also like to highlight the opening sentence of the discussion section; the authors refer to this being a 'comprehensive' survey. We believe this claim is overstated as shown in this letter

  8. Patient exposure evaluation in Romanian radiological departments

    International Nuclear Information System (INIS)

    Girjoaba, O.; Cucu, A.

    2012-01-01

    Purpose: A nation-wide evaluation of ionizing radiation exposure of the Romanian population due to the radiological examinations is performed in accordance with European Directive 97/43 EURATOM implemented in national regulations. Method: The study is applied to the collected data from radiological departments from Romanian hospitals during 2010. The radiological examinations were grouped in three categories: conventional diagnostic radiology, interventional radiology and computed tomography. The annual collective dose was determined from the reported data about the mean effective doses and the frequency for each type of radiological examination, in conformity with the national regulations. Regarding the frequency aspects, the results include the age and gender distributions. Major results: More then 6 million radiological examinations were performed in 2010, Romania having a population about of 20.3 million inhabitants. The collective effective dose for 2010 resulted from the study is 152 mSv per 1000 inhabitants. Conclusions: Medical practitioners must select the best medical imaging investigation for each clinical case taking into account the importance of keeping the patient dose as low as possible. Medical physicists should be strongly involved in the establishing of the dosimetry procedures. (author)

  9. Evaluation of occupational exposure in intraoral radiography

    International Nuclear Information System (INIS)

    Miguel, Cristiano; Barros, Frieda S.; Rocha, Anna S.P.S.; Godoi, Walmor C.; Tilly Junior, Joao G.

    2014-01-01

    The intraoral radiography is widely performed in the dental office due to low cost and agility. The doses in intraoral radiology are considered low, however it is known that doses below the threshold for deterministic radiation has the potential to induce stochastic effects. An intraoral radiography has a risk of inducing fatal cancer or serious in order of 1:10,000,000. Besides the patient, the dentist may also be being exposed to radiation during the work with the radiographics practices. The bibliographies demonstrates the lack of information on radiation protection of dentists, however, the occupational dose reduction was observed in radiology over the past 14 years. This work aims to evaluate the effective dose of radiation to which workers can be exposed dentists in dental offices to perform intraoral radiographs. In this context, a study was be conducted between June 2013 and May 2014 with 44 professionals in Curitiba city. For each dentist was given a personal dosimeter to be used for 30 days. During this period, the number of radiographies and the length of the cable triggers of the X-ray equipment was registered and, the dosimeter´s dose was read. It was observed that the cables triggers meet regulatory standards and allow dentists to get the mean minimum distance of two meters from the radiation source in 93% of cases. Through analysis of the doses, it was concluded that occupational exposures of these workers are within the recommended threshold by regulatory 453/1998 of the Ministry of Health from Brazil. (author)

  10. Radiofrequency fields associated with the Itron smart meter.

    Science.gov (United States)

    Tell, R A; Sias, G G; Vazquez, A; Sahl, J; Turman, J P; Kavet, R I; Mezei, G

    2012-08-01

    This study examined radiofrequency (RF) emissions from smart electric power meters deployed in two service territories in California for the purpose of evaluating potential human exposure. These meters included transmitters operating in a local area mesh network (RF LAN, ∼250 mW); a cell relay, which uses a wireless wide area network (WWAN, ∼1 W); and a transmitter serving a home area network (HAN, ∼70 mW). In all instances, RF fields were found to comply by a wide margin with the RF exposure limits established by the US Federal Communications Commission. The study included specialised measurement techniques and reported the spatial distribution of the fields near the meters and their duty cycles (typically smart meters as deployed. However, the results are restricted to a single manufacturer's emitters.

  11. Aesthetic Applications of Radiofrequency Devices.

    Science.gov (United States)

    Sadick, Neil; Rothaus, Kenneth O

    2016-07-01

    Radiofrequency (RF)-based devices are used to improve face and neck laxity, a major feature of aging that until recently could only be addressed with surgery. Although these treatments are not meant to replace surgical procedures, patient satisfaction studies have been consistently high. For physicians offering these skin rejuvenation procedures, it is essential to have intimate knowledge of how the devices work, select appropriate candidates, set realistic expectations, and combine treatments to optimize outcomes. This article discusses the various noninvasive RF technologies currently in use and reviews pertinent clinical studies evaluating their efficacy and safety. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Evaluation of reproductive function of female rats exposed to radiofrequency fields (27. 12 MHz) near a shortwave diathermy device

    Energy Technology Data Exchange (ETDEWEB)

    Brown-Woodman, P.D.; Hadley, J.A.; Richardson, L.; Bright, D.; Porter, D.

    1989-04-01

    In recent years, there has been increased concern regarding effects of operator exposure to the electromagnetic (EM) field associated with shortwave diathermy devices. The present study was designed to investigate the effects, on rats, of repeated exposure to such an EM field. Following repeated exposure for 5 wk, a reduction in fertility occurred as indicated by a reduced number of matings in exposed rats compared to sham-irradiated rats and a reduction in the number of rats that conceived after mating. The data suggest that female operators could experience reduced fertility, if they remained close to the console for prolonged periods. This has particular significant for the physiotherapy profession.

  13. Multi-Center Pilot Study to Evaluate the Safety Pro le of High Energy Fractionated Radiofrequency With Insulated Microneedles to Multiple Levels of the Dermis.

    Science.gov (United States)

    Cohen, Joel L; Weiner, Steven F; Pozner, Jason N; Ibrahimi, Omar A; Vasily, David B; Ross, E Victor; Gabriel, Zena

    2016-11-01

    In this multi-center pilot study, the safety pro le of high intensity focused radiofrequency (RF) delivered to the dermis was evaluated for safety in the treatment of the aging neck and face. A newly designed insulated microneedle system delivers a signi cant coagulative thermal injury into the dermis while sparing the epidermis from RF injury. Thirty- ve healthy subjects from seven aesthetic practices were evaluated, and data from each were incorporated in this case report. The subjects received a single treatment using settings that delivered the highest RF energies suggested from the new recommended protocols. The depth of thermal delivery was adjusted before each pass and all subjects received a minimum of two to three passes to the treated areas. Before and after photographs along with adverse effects were recorded. This case report demonstrates the ability to deliver significant RF thermal injury to several layers of the dermis with insulated microneedles safely with little injury to the epidermis and minimum downtime. J Drugs Dermatol. 2016;15(11):1308-1312..

  14. Evaluation of the safety and efficacy of a monopolar nonablative radiofrequency device for the improvement of vulvo-vaginal laxity and urinary incontinence.

    Science.gov (United States)

    Lalji, Shelena; Lozanova, Paula

    2017-06-01

    Vaginal childbirth, natural process of aging, congenital factors, and surgical interventions are considered the main causes of vulvo-vaginal laxity driven by changes in collagen and elastin fibers. This causes a loss of strength and flexibility within the vaginal wall. As a result, women may experience lack of sensation and stress urinary incontinence (SUI)-the condition of involuntary loss of urine associated with activities that cause an increase in intra-abdominal pressure (eg, sneezing, coughing, and lifting). Both vaginal laxity and urinary incontinence significantly affect patients' quality of life (QoL). The aim of this study was to evaluate efficacy and safety of a noninvasive radiofrequency device when used to treat SUI and vulvo-vaginal laxity through its heating effect which stimulates collagen and elastin fibers. Twenty-seven women (average age 44.78±10.04 years) with indications of mild/moderate SUI as well as vulvo-vaginal laxity were treated with a monopolar radiofrequency device. The treatment course consisted of three once-a-week sessions. Each session included intravaginal treatment followed by treatment of labia majora and the perineum. Improvement in the SUI condition was evaluated by applying the International Consultation on Incontinence Questionnaire - Urinary Incontinence Short Form (ICIQ-UI SF). Data were collected at the baseline, after the last treatment and at 1-month follow-up visit. Vaginal laxity was assessed by subjective vulvo-vaginal laxity questionnaire (VVLQ). Data were collected before the 1st treatment and during the 1-month follow-up visit. Patient's satisfaction was recorded using a satisfaction questionnaire. Data were collected after the last treatment and at the 1-month follow-up visit. Any adverse events related to the treatments were monitored. On a scale of 0 to 5, the average frequency of urine leak improved from "2-3 times a week" (2.15±1.03 points prior to treatment) to "once a week" (1.00±0.78 points post

  15. CT-guided radiofrequency tumor ablation in children.

    Science.gov (United States)

    Botsa, Evanthia; Poulou, Loukia S; Koutsogiannis, Ioannis; Ziakas, Panayiotis D; Koundouraki, Antonia; Alexopoulou, Efthimia; Thanos, Loukas

    2014-11-01

    Image-guided radiofrequency ablation is a well-accepted technique of interventional oncology in adults. To evaluate the efficacy and safety of CT-guided radiofrequency ablation as a minimally invasive treatment for metastatic neoplasms in children. A total of 15 radiofrequency ablation sessions were performed in 12 children and young adults (median age 9.5; range 5-18 years) with metastatic malignancies. Seven children and young adults had secondary hepatic lesions, three had pulmonary and two had bone lesions. Radiofrequency ablation was performed under conscious sedation. The median lesion size was 1.7 cm (range 1.3-2.8 cm). The median time for ablation was 8 min (range 7-10 min). Radiofrequency procedures were technically successful in all tumors. Postablation imaging immediately after, and 1 month and 3 months after radiofrequency ablation showed total necrosis in all patients. At 6-month follow-up, three patients (all with lesion size >2 cm) had local recurrence and underwent a second radiofrequency ablation session. At 2-year follow-up no patient had recurrence of the treated tumor. Post-ablation syndrome occurred in four children. No major complication occurred. CT-guided radiofrequency tumor ablation was safe and efficient for palliative treatment in our cohort of patients.

  16. CT-guided radiofrequency tumor ablation in children

    Energy Technology Data Exchange (ETDEWEB)

    Botsa, Evanthia [National and Kapodistrian University of Athens, First Pediatric Clinic, Agia Sofia Children' s Hospital, Athens (Greece); Poulou, Loukia S.; Koundouraki, Antonia; Thanos, Loukas [Sotiria General Hospital for Chest Diseases, Department of Medical Imaging and Interventional Radiology, Athens (Greece); Koutsogiannis, Ioannis [General Military Hospital NIMTS, Department of Medical Imaging, Athens (Greece); Ziakas, Panayiotis D. [Warren Alpert Medical School of Brown University Rhode Island Hospital, Division of Infectious Diseases, Providence, RI (United States); Alexopoulou, Efthimia [Attikon University Hospital, Second Department of Radiology, Athens University School of Medicine, Athens (Greece)

    2014-11-15

    Image-guided radiofrequency ablation is a well-accepted technique of interventional oncology in adults. To evaluate the efficacy and safety of CT-guided radiofrequency ablation as a minimally invasive treatment for metastatic neoplasms in children. A total of 15 radiofrequency ablation sessions were performed in 12 children and young adults (median age 9.5; range 5-18 years) with metastatic malignancies. Seven children and young adults had secondary hepatic lesions, three had pulmonary and two had bone lesions. Radiofrequency ablation was performed under conscious sedation. The median lesion size was 1.7 cm (range 1.3-2.8 cm). The median time for ablation was 8 min (range 7-10 min). Radiofrequency procedures were technically successful in all tumors. Postablation imaging immediately after, and 1 month and 3 months after radiofrequency ablation showed total necrosis in all patients. At 6-month follow-up, three patients (all with lesion size >2 cm) had local recurrence and underwent a second radiofrequency ablation session. At 2-year follow-up no patient had recurrence of the treated tumor. Post-ablation syndrome occurred in four children. No major complication occurred. CT-guided radiofrequency tumor ablation was safe and efficient for palliative treatment in our cohort of patients. (orig.)

  17. Evaluation of the cloudy sky solar UVA radiation exposures.

    Science.gov (United States)

    Parisi, A V; Downs, N; Turner, J

    2014-09-05

    The influence of cloud on the solar UVA (320-400 nm) exposures over five minute periods on a horizontal plane has been investigated. The first approach used cloud modification factors that were evaluated using the influence of clouds on the global solar exposures (310-2800 nm) and a model developed to apply these to the clear sky UVA exposures to allow calculation of the five minute UVA exposures for any cloud conditions. The second approach established a relationship between the UVA and the global solar exposures. The models were developed using the first six months of data in 2012 for SZA less than or equal to 70° and were applied and evaluated for the exposures in the second half of 2012. This comparison of the modelled exposures for all cloud conditions to the measured data provided an R(2) of 0.8 for the cloud modification model, compared to an R(2) of 0.7 for the UVA/global model. The cloud modification model provided 73% of the five minute exposures within 20% of the measured UVA exposures. This was improved to 89% of the exposures within 20% of the measured UVA exposures for the cases of cloud with the sun not obscured. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Radiofrequency Energy and Electrode Proximity Influences Stereoelectroencephalography-Guided Radiofrequency Thermocoagulation Lesion Size: An In Vitro Study with Clinical Correlation.

    Science.gov (United States)

    Staudt, Michael D; Maturu, Sarita; Miller, Jonathan P

    2018-02-16

    Radiofrequency thermocoagulation of epileptogenic foci via stereoelectroencephalography (SEEG) electrodes has been suggested as a treatment for medically intractable epilepsy, but reported outcomes have been suboptimal, possibly because lesions generated using conventional high-energy radiofrequency parameters are relatively small. To describe a technique of delivering low energy across separate SEEG electrodes in order to create large confluent radiofrequency lesions. The size and configuration of radiofrequency lesions using different radiofrequency intensity and interelectrode distance was assessed in egg whites. Magnetic resonance images (MRI) from 3 patients who had undergone radiofrequency lesion creation were evaluated to determine the contribution of lesion intensity and electrode separation on lesion size. Electroencephalography, MRI, and clinical data were assessed before and after lesion creation. Both in Vitro and in Vivo analysis revealed that less energy paradoxically produced larger lesions, with the largest possible lesions produced when radiofrequency power was applied for long duration at less than 3 W. Linear separation of electrodes also contributed to lesion size, with largest lesions produced when electrodes were separated by a linear distance of between 5 and 12 mm. Clinical lesions produced using these parameters were large and resulted in improvement in interictal and ictal activity. Radiofrequency lesions produced using low-energy delivery between SEEG electrodes in close proximity can produce a large lesion. These findings might have advantages for treatment of focal epilepsy.

  19. Issues in epidemiological studies of radiofrequency workers

    International Nuclear Information System (INIS)

    Hocking, B.

    1985-01-01

    The paper reviews some of the issues in a proposed epidemiological study of radiofrequency workers. First a few other epidemiological studies are discussed to illustrate some of the common problems such as inadequate definition of effects and/or exposure. Then technical problems in determining dosage and responses as well as study design are reviewed, and finally the administrative aspects of ethics, industrial relations and costs are considered

  20. Use of peak nasal inspiratory flowmetry and nasal decongestant to evaluate outcome of septoplasty with radiofrequency coblation of the inferior turbinate.

    Science.gov (United States)

    Balikci, H H; Gurdal, M M

    2014-06-01

    To investigate the role of peak nasal inspiratory flowmetry (PNIF) in evaluating inspiratory improvements in patients who underwent both septoplasty and inferior turbinate coblation by radiofrequency (ITC-RF). One hundred and eight patients underwent both Cottle's septoplasty and ITC-RF. PNIF measurements were performed in all patients in the preoperative period and 6 months postoperatively. All measurements were made both before and after decongestion of the nasal cavity with oxymetazoline spray. Mean preoperative PNIF measurements differed significantly: 104.3 ± 33.6 L/min vs 136.1 ± 27.7 L/min before and after oxymetazoline decongestion, respectively. Mean postoperative PNIF measurements were 139.2 ± 30.8 L/min and 151.2 ± 32.3 L/min before and after decongestion, respectively. Preoperatively the mean difference between before and after decongestion was 32.1 ± 16.3 L/min. Postoperatively the mean difference was 11.8 ± 11.1 L/min. PNIF can be used in the assessment of ITC-RF outcomes with the aid of nasal decongestants, even in patients who also underwent septoplasty.

  1. Evaluation of left atrial function by multidetector computed tomography before left atrial radiofrequency-catheter ablation: Comparison of a manual and automated 3D volume segmentation method

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, Florian, E-mail: florian.wolf@meduniwien.ac.a [Department of Radiology, Medical University of Vienna, Vienna (Austria); Ourednicek, Petr [Philips Medical Systems, Prague (Czech Republic); Loewe, Christian [Department of Radiology, Medical University of Vienna, Vienna (Austria); Richter, Bernhard; Goessinger, Heinz David; Gwechenberger, Marianne [Department of Cardiology, Medical University of Vienna, Vienna (Austria); Plank, Christina; Schernthaner, Ruediger Egbert; Toepker, Michael; Lammer, Johannes [Department of Radiology, Medical University of Vienna, Vienna (Austria); Feuchtner, Gudrun M. [Department of Radiology, Innsbruck Medical University, Innsbruck (Austria); Institute of Diagnostic Radiology, University Hospital Zurich (Switzerland)

    2010-08-15

    Introduction: The purpose of this study was to compare a manual and automated 3D volume segmentation tool for evaluation of left atrial (LA) function by 64-slice multidetector-CT (MDCT). Methods and materials: In 33 patients with paroxysmal atrial fibrillation a MDCT scan was performed before radiofrequency-catheter ablation. Atrial function (minimal volume (LAmin), maximal volume (LAmax), stroke volume (SV), ejection fraction (EF)) was evaluated by two readers using a manual and an automatic tool and measurement time was evaluated. Results: Automated LA volume segmentation failed in one patient due to low LA enhancement (103HU). Mean LAmax, LAmin, SV and EF were 127.7 ml, 93 ml, 34.7 ml, 27.1% by the automated, and 122.7 ml, 89.9 ml, 32.8 ml, 26.3% by the manual method with no significant difference (p > 0.05) and high Pearsons correlation coefficients (r = 0.94, r = 0.94, r = 0.82 and r = 0.85, p < 0.0001), respectively. The automated method was significantly faster (p < 0.001). Interobserver variability was low for both methods with Pearson's correlation coefficients between 0.98 and 0.99 (p < 0.0001). Conclusions: Evaluation of LA volume and function with 64-slice MDCT is feasible with a very low interobserver variability. The automatic method is as accurate as the manual method but significantly less time consuming permitting a routine use in clinical practice before RF-catheter ablation.

  2. Radiofrequency ablation of liver metastases-software-assisted evaluation of the ablation zone in MDCT: tumor-free follow-up versus local recurrent disease.

    Science.gov (United States)

    Keil, Sebastian; Bruners, Philipp; Schiffl, Katharina; Sedlmair, Martin; Mühlenbruch, Georg; Günther, Rolf W; Das, Marco; Mahnken, Andreas H

    2010-04-01

    The purpose of this study was to investigate differences in change of size and CT value between local recurrences and tumor-free areas after CT-guided radiofrequency ablation (RFA) of hepatic metastases during follow-up by means of dedicated software for automatic evaluation of hepatic lesions. Thirty-two patients with 54 liver metastases from breast or colorectal cancer underwent triphasic contrast-enhanced multidetector-row computed tomography (MDCT) to evaluate hepatic metastatic spread and localization before CT-guided RFA and for follow-up after intervention. Sixteen of these patients (65.1 + or - 10.3 years) with 30 metastases stayed tumor-free (group 1), while the other group (n = 16 with 24 metastases; 62.0 + or - 13.8 years) suffered from local recurrent disease (group 2). Applying an automated software tool (SyngoCT Oncology; Siemens Healthcare, Forchheim, Germany), size parameters (volume, RECIST, WHO) and attenuation were measured within the lesions before, 1 day after, and 28 days after RFA treatment. The natural logarithm (ln) of the quotient of the volume 1 day versus 28 days after RFA treament was computed: lnQ1//28/0(volume). Analogously, ln ratios of RECIST, WHO, and attenuation were computed and statistically evaluated by repeated-measures ANOVA. One lesion in group 2 was excluded from further evaluation due to automated missegmentation. Statistically significant differences between the two groups were observed with respect to initial volume, RECIST, and WHO (p free and local-recurrent ablation zones with respect to the corresponding size parameters. A new parameter (lnQ1//28/0(volume/RECIST/WHO/attenuation)) was introduced, which appears to be of prognostic value at early follow-up CT.

  3. Vitamin C protects rat cerebellum and encephalon from oxidative stress following exposure to radiofrequency wave generated by a BTS antenna model.

    Science.gov (United States)

    Akbari, Abolfazl; Jelodar, Gholamali; Nazifi, Saeed

    2014-06-01

    Radio frequency wave (RFW) generated by base transceiver station has been reported to produce deleterious effects on the central nervous system function, possibly through oxidative stress. This study was conducted to evaluate the effect of RFW-induced oxidative stress in the cerebellum and encephalon and the prophylactic effect of vitamin C on theses tissues by measuring the antioxidant enzymes activity, including: glutathione peroxidase, superoxide dismutase, catalase, and malondialdehyde (MDA). Thirty-two adult male Sprague-Dawley rats were randomly divided into four equal groups. The control group; the control-vitamin C group received L-ascorbic acid (200 mg/kg of body weight/day by gavage) for 45 days. The RFW group was exposed to RFW and the RFW+ vitamin C group was exposed to RFW and received vitamin C. At the end of the experiment, all groups were killed and encephalon and cerebellum of all rats were removed and stored at -70 °C for measurement of antioxidant enzymes activity and MDA. The results indicate that exposure to RFW in the test group decreased antioxidant enzymes activity and increased MDA compared with the control groups (p < 0.05). The protective role of vitamin C in the treated group improved antioxidant enzymes activity and reduced MDA compared with the test group (p < 0.05). It can be concluded that RFW causes oxidative stress in the brain and vitamin C improves the antioxidant enzymes activity and decreases MDA.

  4. Development and evaluation of an Exposure Control Efficacy Library (ECEL)

    NARCIS (Netherlands)

    Fransman, W.; Schinkel, J.; Meijster, T.; Hemmen, J. van; Tielemans, E.; Goede, H.

    2008-01-01

    Objectives: This paper describes the development and evaluation of an evidence database on the effectiveness of risk management measures (RMMs) to control inhalation exposure. This database is referred to as Exposure Control Efficacy Library (ECEL). Methods: A comprehensive review of scientific

  5. Exposure to violence in children referred for psychiatric evaluation ...

    African Journals Online (AJOL)

    One hundred consecutive patients referred to the Child Mental Health Section of Oranje Hospital in Bloemfontein for psychiatric evaluation were included in the study. Seventy-four per cent of children in the study reported exposure to some form of violence in the past: 32% reported exposure to domestic violence, 9% ...

  6. Overview of UNSCEAR re-evaluation of public exposure

    Energy Technology Data Exchange (ETDEWEB)

    Rochedo, Elaine R.R. [Comissao Nacional de Energia Nuclear (CNEN-RJ), Rio de Janeiro, RJ (Brazil). Coordenacao de Instalacoes Nucleares], e-mail: erochedo@cnen.gov.br

    2009-07-01

    The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has re-evaluated the levels of public radiation exposure for four broad categories of sources: natural sources of radiation, enhanced exposure to naturally occurring radioactive material (NORM), man-made sources used for peaceful purposes and man-made sources used for military purposes. Regarding natural radiation sources, recent data confirmed former results from 2000 Report, but with a more wide range. Very few information is available for public exposure from NORM. Most works describes concentration levels but dose assessments are usually restricted to occupational exposures. The use of source and by-product materials may however lead to doses up to a few milisieverts to members of the public. The nuclear fuel cycle and electric energy generation have very small contributions to public exposure. Uranium mining contributes with the largest individual doses, mainly due to radon from tailings. Most relevant military use of nuclear energy were the atmospheric nuclear tests, interrupted in the 60's. Residual radioactivity deposited worldwide is now responsible for a very small contribution to worldwide exposures. However, they left a legacy of several contaminated sites. The use of depleted uranium in munitions in Kuwait, Kosovo, Serbia, Montenegro and Bosnia-Herzegovina, has led to great public concern, although not usually associated to any major consequence regarding public exposure. Some accidents resulted in environmental contamination and exposures of members of the public. Except for the Chernobyl accident, the areas affected were usually small and the exposure restricted to small number of persons, up to a few hundred, without any significant contribution to worldwide exposures. The exposure to natural sources of radiation is still the major component of worldwide exposure to ionizing radiation although for some highly developed countries, medical exposure has surpassed

  7. Overview of UNSCEAR re-evaluation of public exposure

    International Nuclear Information System (INIS)

    Rochedo, Elaine R.R.

    2009-01-01

    The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has re-evaluated the levels of public radiation exposure for four broad categories of sources: natural sources of radiation, enhanced exposure to naturally occurring radioactive material (NORM), man-made sources used for peaceful purposes and man-made sources used for military purposes. Regarding natural radiation sources, recent data confirmed former results from 2000 Report, but with a more wide range. Very few information is available for public exposure from NORM. Most works describes concentration levels but dose assessments are usually restricted to occupational exposures. The use of source and by-product materials may however lead to doses up to a few milisieverts to members of the public. The nuclear fuel cycle and electric energy generation have very small contributions to public exposure. Uranium mining contributes with the largest individual doses, mainly due to radon from tailings. Most relevant military use of nuclear energy were the atmospheric nuclear tests, interrupted in the 60's. Residual radioactivity deposited worldwide is now responsible for a very small contribution to worldwide exposures. However, they left a legacy of several contaminated sites. The use of depleted uranium in munitions in Kuwait, Kosovo, Serbia, Montenegro and Bosnia-Herzegovina, has led to great public concern, although not usually associated to any major consequence regarding public exposure. Some accidents resulted in environmental contamination and exposures of members of the public. Except for the Chernobyl accident, the areas affected were usually small and the exposure restricted to small number of persons, up to a few hundred, without any significant contribution to worldwide exposures. The exposure to natural sources of radiation is still the major component of worldwide exposure to ionizing radiation although for some highly developed countries, medical exposure has surpassed the

  8. Evaluation of exposure to carbon monoxide associated with passive smoking

    International Nuclear Information System (INIS)

    Jo, W.-K.; Oh, J.-W.; Dong, J.-I.

    2004-01-01

    The current study measured breath carbon monoxide (CO) concentrations prior to and at prescribed time intervals after exposure to passive smoking under controlled conditions, along with the air CO concentration in the exposure room during the exposure periods. The postexposure breath CO levels were 1.4-2.7 times higher than the background breath CO levels after 30 min of exposure, yet only slightly higher after 10 min of exposure, thereby confirming that exposure to CO from passive smoking causes a significant body burden of CO. The air CO concentration gradually increased during the burning of a cigarette(s), regardless of the exposure duration, whereas it slightly decreased after burning. However, the pattern of breath CO decay was similar for the two different types of exposure (during and after a cigarette(s)) in each subject. The decrease in the postexposure alveolar CO concentrations was slow even in the early phase of the decay curves, indicating a monocompartment uptake and elimination model for the human body. The half-lives (78-277 min) estimated in the present study were comparable to those reported in previous studies associated with CO exposure from active smoking or other activities. The current study also evaluated the CO exposure of visitors and workers at three different types of recreation facility (bars, Internet cafes, and billiard halls) typically associated with passive smoking. The results confirmed that passive smoking is the major contributor to the CO exposure of nonsmoking visitors in a recreation environment. In addition, workplace exposure to CO from passive smoking was found to be the most important contributor to the daily CO exposure of nonsmoking recreation workers

  9. Percutaneous radiofrequency thermal ablation of lung VX2 tumors in a rabbit model: evaluation with helical CT findings for the complete and partal ablation

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Gong Yong; Han, Young Min; Lim, Yeong Su; Jang, Kyu Yun; Lee, Sang Yong; Chung, Gyung Ho [School of Medicine, Chonbuk National Univ., Chonju (Korea, Republic of)

    2004-05-01

    To evaluate the radiologic findings for complete and partial ablation after percutaneous CT-guided transthoracic radiofrequency ablation (RFA) of lung VX2 tumor implanted in rabbits. Thirteen rabbits with successfully implanted lung VX2 were used. Three rabbits as controls did not receive RFA while the other ten rabbits underwent RFA; 5 complete and 5 partial. RFA was performed using an internally cooled, 17-gauge electrode (Radionics, Burlington, MA) with a 1-cm active tip under CT guidance. Postprocedural CT was performed within 3 days, and we analyzed the ablated size, enhancement pattern, shape, margin, and complications of the complete and partial ablation groups. Rabbits were sacrificed after postprocedural CT with an overdose of ketamine, and pathologic findings of the ablated groups were compared with those of the control group. The size of the ablated lesions and the enhancement pattern differed between the completely and partially ablated groups on chest CT. The size of the ablated lesions was increased by 47.1% in the completely ablated group and by 2.1% in the partially ablated group. In the completely ablated group, VX2 tumor showed absolutely no enhancement, whereas only ablated pulmonary parenchyma outside VX2 showed mild enhancement on enhanced CT. In the partial ablated group, a part of VX2 became strongly enhanced on enhanced CT. On microscopic examination, the completely ablated group demonstrated that a viable tumor cell was not visible. In the partially ablated group, however, a viable tumor cell within the surrounding fibrous capsule on the peripheral area of the VX2 was observed. The important CT findings for evaluation of complete and partial RFA are the ablated size and enhancement pattern of the ablated lesion.

  10. Clinical evaluation of simultaneously applied monopolar radiofrequency and targeted pressure energy as a new method for noninvasive treatment of cellulite in postpubertal women.

    Science.gov (United States)

    Fritz, Klaus; Salavastru, Carmen; Gyurova, Magdalina

    2018-03-09

    This study investigates noninvasive cellulite treatments based on simultaneous application of monopolar radiofrequency (RF) and targeted pressure energy to evaluate efficacy and safety and to see whether simultaneous application has any benefits in noninvasive cellulite treatments. Thirty women with cellulite (fibrous/adipose/aqueous types) received 4 gluteofemoral treatments (~24 minutes; ~1000 cm 2 ) using a simultaneous application of RF and targeted pressure energy. Clinical improvement was assessed using a pentile grading scale and satisfaction questionnaires. Hip/thigh circumference was measured. Ultrasonography and thermography observed changes in dermal/subcutaneous tissue composition and in gluteofemoral thermal profile. Evaluation at 3 months posttreatment was compared against the baseline. The clinical improvement averaged 2.17 ± 0.95 (54% improvement). Cellulite was reduced in 93% of cases, while 73% of patients showed good/very good/excellent improvement, with most significant improvement seen in patients with moderately severe cellulite. Hips and thigh circumference decreased on average by 2.31 cm and 2.13 cm, respectively (P cellulite reduction had a more homogenous thermal profile at follow-up as a result of therapy-induced diminution of topographic skin defects. No adverse events were recorded. The application is effective and safe for treating cellulite. The level of clinical improvement after 4 sessions is comparable to results reported after 6-20 sessions in studies on stand-alone RF/laser/targeted pressure energy devices. The technology is promising and deserves further attention and research. © 2018 The Authors. Journal of Cosmetic Dermatology Published by Wiley Periodicals, Inc.

  11. Evaluation of occupational exposures in the Czech Republic

    International Nuclear Information System (INIS)

    Prouza, Z.; Petrova, K.

    1996-01-01

    The recent situation in the Czech Republic (CZ) concerning the evaluation and recording of occupational radiation exposures is described. The individual monitoring is based on the interpretation of the personal dosemeters responses and the evaluation of the other special dosimetric methods (measurement of excrete, whole body counting, etc.). The evaluation of occupational radiation exposures is carried out by five approved dosimetric services, which control about 20,000 workers. Record keeping of overexposures is based on two systems, which principles are explained. Based on long time analysis of occupational radiation exposures in CZ it can be present that the average values and trends of individual and collective effective dose equivalents are comparable with those in developed countries. The distributions of the radiation exposures for the important occupational groups of workers are presented. (author)

  12. Evaluation of medical radiation exposure in pediatric interventional radiology procedures

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, Valeria Coelho Costa; Navarro, Marcus Vinicius Teixeira; Oliveira, Aline da Silva Pacheco, E-mail: vccnavarro@gmail.com [Instituto Federal de Educacao, Ciencia e Tecnologia da Bahia (IFBA), Salvador, BA (Brazil); Maia, Ana Figueiredo [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil); Oliveira, Adriano Dias Dourado [Sociedade Brasileira de Hemodinamica e Cardiologia Intervencionista, Salvador, BA (Brazil)

    2012-07-15

    Objective: To evaluate pediatric radiation exposure in procedures of interventional radiology in two hospitals in the Bahia state, aiming at contributing to delineate the scenario at the state and national levels. The knowledge of exposure levels will allow an evaluation of the necessity of doses optimization, considering that peculiarities of radiology and pediatrics become even more significant in interventional radiology procedures which involve exposure to higher radiation doses. Materials and Methods: A total of 32 procedures were evaluated in four rooms of the two main hospitals performing pediatric interventional radiology procedures in the Bahia state. Air kerma rate and kerma-area product were evaluated in 27 interventional cardiac and 5 interventional brain procedures. Results: Maximum values for air kerma rate and kerma-area product and air kerma obtained in cardiac procedures were, respectively, 129.9 Gy.cm{sup 2} and 947.0 mGy; and, for brain procedures were 83.3 Gy.cm{sup 2} and 961.0 mGy. Conclusion: The present study results showed exposure values up to 14 times higher than those found in other foreign studies, and approximating those found for procedures in adults. Such results demonstrate excessive exposure to radiation, indicating the need for constant procedures optimization and evaluation of exposure rates. (author)

  13. Evaluation of natural radiation exposure of the French population

    International Nuclear Information System (INIS)

    Billon, S.; Morin, A.; Baysson, H.; Gambard, J.P.; Rannou, A.; Tirmarche, M.; Laurier, D.; Caer, S.

    2004-01-01

    Exposure of the French population to ionising radiation is mainly due to natural radiation (i.e. exposure through: inhalation of radon decay products, external radiation of terrestrial and cosmic origin and water and food ingestion). In an epidemiological context, it is necessary to estimate as precisely as possible the population exposure, in order to study its influence on health indicators. In this aim, indicators of population exposure should be created taking into account results of environmental measurements by controlling the different factors that may influence these measurements (dwelling characteristics, seasonal variations, population density). The distribution of these exposures should also be studied at different geographical levels (department, job area). This work updates the estimation of the French population exposure to natural radiation. Radon exposure indicators have been based on concentrations measured in dwellings, corrected on season and dwelling characteristics (departmental range: 19-297 Bq/m 3 ). Indicators of terrestrial gamma ray exposure have been based on measured indoor and outdoor dose rates adjusted on dwelling characteristics (22-95 nSv/h). Cosmic ray exposure has been evaluated from altitude and weighted by population density (0.27-0.38 mSv/yr). Due to these three components, the effective annual dose was estimated to be at 2.2 mSv. (author)

  14. Temperature Controlled Radiofrequency Ablation

    Directory of Open Access Journals (Sweden)

    Olaf J. Eick

    2002-07-01

    Full Text Available Since its introduction in 1987, radiofrequency (RF ablation has developed to become the treatment of choice for symptoms caused by atrio ventricular (AV reentrant tachycardia, isthmus related atrial flutter, AV-nodal reentrant tachycardia and to some extent also for certain types of ventricular tachycardias. The introduction of new cardiac activation mapping systems has further contributed to the successful and safe application of RF ablation for various tachyarrhythmias.

  15. Laser and Radiofrequency Air Plasma Sources

    National Research Council Canada - National Science Library

    Scharer, J

    2003-01-01

    .... We have measured plasma density decay rates and been successful in radiofrequency sustainment of the laser-produced plasmas with reduced power levels compared to radiofrequency ionization alone...

  16. A Multi-Band Body-Worn Distributed Radio-Frequency Exposure Meter: Design, On-Body Calibration and Study of Body Morphology

    Science.gov (United States)

    Thielens, Arno; Agneessens, Sam; Van Torre, Patrick; Van den Bossche, Matthias; Eeftens, Marloes; Huss, Anke; Vermeulen, Roel; de Seze, René; Mazet, Paul; Cardis, Elisabeth; Röösli, Martin; Martens, Luc; Joseph, Wout

    2018-01-01

    A multi-band Body-Worn Distributed exposure Meter (BWDM) calibrated for simultaneous measurement of the incident power density in 11 telecommunication frequency bands, is proposed. The BDWM consists of 22 textile antennas integrated in a garment and is calibrated on six human subjects in an anechoic chamber to assess its measurement uncertainty in terms of 68% confidence interval of the on-body antenna aperture. It is shown that by using multiple antennas in each frequency band, the uncertainty of the BWDM is 22 dB improved with respect to single nodes on the front and back of the torso and variations are decreased to maximum 8.8 dB. Moreover, deploying single antennas for different body morphologies results in a variation up to 9.3 dB, which is reduced to 3.6 dB using multiple antennas for six subjects with various body mass index values. The designed BWDM, has an improved uncertainty of up to 9.6 dB in comparison to commercially available personal exposure meters calibrated on body. As an application, an average incident power density in the range of 26.7–90.8 μW·m−2 is measured in Ghent, Belgium. The measurements show that commercial personal exposure meters underestimate the actual exposure by a factor of up to 20.6. PMID:29346280

  17. Prenatal exposure to radiofrequencies: effects of WiFi signals on thymocyte development and peripheral T cell compartment in an animal model.

    Science.gov (United States)

    Laudisi, Federica; Sambucci, Manolo; Nasta, Francesca; Pinto, Rosanna; Lodato, Rossella; Altavista, Pierluigi; Lovisolo, Giorgio Alfonso; Marino, Carmela; Pioli, Claudio

    2012-12-01

    Wireless local area networks are an increasing alternative to wired data networks in workplaces, homes, and public areas. Concerns about possible health effects of this type of signal, especially when exposure occurs early in life, have been raised. We examined the effects of prenatal (in utero) exposure to wireless fidelity (WiFi) signal-associated electromagnetic fields (2450 MHz center-frequency band) on T cell development and function. Pregnant mice were exposed whole body to a specific absorption rate of 4 W/kg, 2 h per day, starting 5 days after mating and ending 1 day before the expected delivery. Sham-exposed and cage control groups were used as controls. No effects on cell count, phenotype, and proliferation of thymocytes were observed. Also, spleen cell count, CD4/CD8 cell frequencies, T cell proliferation, and cytokine production were not affected by the exposure. These findings were consistently observed in the male and female offspring at early (5 weeks of age) and late (26 weeks of age) time points. Nevertheless, the expected differences associated with aging and/or gender were confirmed. In conclusion, our results do not support the hypothesis that the exposure to WiFi signals during prenatal life results in detrimental effects on the immune T cell compartment. Copyright © 2012 Wiley Periodicals, Inc.

  18. Hsp70 expression and free radical release after exposure to non-thermal radio-frequency electromagnetic fields and ultrafine particles in human Mono Mac 6 cells.

    Science.gov (United States)

    Simkó, M; Hartwig, C; Lantow, M; Lupke, M; Mattsson, M-O; Rahman, Q; Rollwitz, J

    2006-02-08

    The contemporary urban environment has become increasingly complex in its composition, leading to discussions regarding possible novel health effects. Two factors that recently have received considerable attention are ultrafine particles (UFP; 217Hz or GSM-nonDTX)), alone or in combination influences levels of the superoxide radical anion or the stress protein heat-shock protein (Hsp70) in the human monocyte cell line Mono Mac 6. Heat treatment (42-43 degrees C, 1h) was used as positive control for both stress reaction and for heat development in the RF exposure setup. Our results clearly show that Mono Mac 6 cells are capable to internalise UFP, and that this phagocytic activity is connected to an increased release of free radicals. This increase (40-45% above negative control) is stronger than the effect of heat treatment. On the other hand, none of the employed RF exposures showed any effects on free radical levels. Co-exposure of RF and UFP did not potentiate the UFP effect either. Our investigations showed a significantly increased Hsp70 expression level by heat treatment in a time-dependent manner, whereas UFP, RF, or UFP+RF were without any effect. Therefore, we conclude that in the investigated Mono Mac 6 cells, RF exposure alone or in combination with UFP cannot influence stress-related responses.

  19. Evaluation of the noise exposure of symphonic orchestra musicians

    Directory of Open Access Journals (Sweden)

    Matilde Alexandra Rodrigues

    2014-01-01

    Full Text Available For musicians, the impact of noise exposure is not yet fully characterized. Some inconsistencies can be found in the methodology used to evaluate noise exposure. This study aims to analyze the noise exposure of musicians in a symphonic orchestra to understand their risk for hearing loss, applying the methodology proposed by ISO 9612:2009. Noise levels were monitored among musicians during the rehearsal of eight different repertoires. Test subjects were selected according to their instrument and position in the orchestra. Participants wore noise dosimeters throughout the rehearsals. A sound meter was used to analyze the exposure of the conductor. The results showed that musicians are exposed to high noise levels that can damage hearing. Brass, woodwind and percussion and timpani musicians were exposed to noise levels in excess of the upper exposure action level of 85 dB (A, while the other instrumental groups had a lower exposure action level of 80 dB (A. Percussion musicians were exposed to high peak noise levels of 135 dB (C. Sound levels varied by instrument, repertoire and position. Octave frequency analyses showed differences among musicians. This study suggests that musicians are at risk for hearing loss. There is a need for more effective guidelines applicable to all countries, which should define standardized procedures for determining musician noise exposure and should allow exposure level normalization to the year, including different repertoires.

  20. Malignant hepatic tumors treated with percutaneous radio-frequency ablation: Comparison between contrast-enhanced color Doppler ultrasound and spiral CT in evaluating the therapeutic efficacy

    International Nuclear Information System (INIS)

    Yoon, Jung Hee; Han, Sang Suk; Cha, Sung Sook

    2002-01-01

    To compare contrast-enhanced color Doppler ultrasound (CECDUS) with spiral CT in the evaluation of the therapeutic efficacy of malignant hepatic tumors after radio-frequency ablation (RFA). During a recent 2 year period (April 1999 to March 2001). One hundred fifteen hepatic tumors (95 hepatocellular carcinomas and 20 metastases; mean diameter, 2.7 cm) from 83 consecutive patients (60 men and 23 women; mean age, 57 years) that were treated with RFA were included in this study. Both CECDUS and two-or three phase spiral CT were performed a day after RFA as the immediate follow-up study in most cases. Afterward, both imaging studies were alternatively performed on monthly basis, but when incomplete ablation was suspected on one follow-up imaging study, the other imaging study was performed within a week for comparison. For ultrasound contrast agent, a suspension of 2.5 g or 4.0 g Levovist (Schering AG, Berlin, Germany) with a concentration of 300 mg/mL was used. For evaluating the therapeutic efficacy, the presence of viable portion, either residual or recurrent, within the ablated tumor was determined on each imaging study. The criteria for viable portion were defined as focal or irregular enhancement at the periphery of the ablated tumor on the arterial or portal phase spiral CT images and intratumoral vascularities on CECDUS. The correspondence rate between both imaging studies was assessed to compare the diagnostic accuracy of both studies in evaluating a residual or recurrent tumor. In addition, their imaging findings were analyzed. Analyzing both imaging findings of 116 malignant hepatic tumors, the correspondence rate between CECDUS and CT obtained after 116 times of imaging studies was 91.4% (106/116). For the diagnosis of residual or recurrent tumors, the sensitivity, specificity and diagnostic accuracy of spiral CT were 71%, 99%, and 94%, respectively, while those of CECDUS were 87%, 99%, and 97%, respectively. As the immediate follow-up study, CECDUS seemed

  1. Occupational exposure assessment in a radioactive facility: a preliminary evaluation

    International Nuclear Information System (INIS)

    Alves, Alice dos Santos; Gerulis, Eduardo; Sanches, Matias P.; Carneiro, Janete C.G.G.

    2013-01-01

    The risk that a worker has found on the job is a function of the hazards present and his exposure level to those hazards. Exposure and risk assessment is therefore the heart of all occupational health and industrial hygiene programs involving a continuous process of information gathering. The use of a systematic method to characterize workplace exposures to chemical, physical and biological risks is a fundamental part of this process. This study aims to carry out a preliminary evaluation in a radioactive facility, identifying potential exposures and consequently the existing occupational hazards (risk/agent) in the workplace which the employee is subject. The study is based on proposal to carry out a basic characterization of the facility, which could be the first step in the investigation of occupational exposure. For this study was essential to know the workplace, potential risks and agents; workforce profile including assignment of tasks, sources of exposure processes, and control measures. The main tool used in this study was based on references, records, standards, procedures, interviews with the workers and with management. Since the basic characterization of the facility has been carried out, consequently the potential exposure to the agents of risks to workers has been identified. The study provided an overview of the perception of risk founded at facility studied. It is expected to contribute with the occupational health program resources for welfare of the worker. (author)

  2. Evaluation and comparison of three exposure assessment techniques.

    Science.gov (United States)

    Neitzel, R L; Daniell, W E; Sheppard, L; Davies, H W; Seixas, N S

    2011-05-01

    This study was conducted to verify the performance of a recently developed subjective rating (SR) exposure assessment technique and to compare estimates made using this and two other techniques (trade mean, or TM, and task-based, or TB, approaches) to measured exposures. Subjects (n = 68) each completed three full-shift noise measurements over 4 months. Individual measured mean exposures were created by averaging each subject's repeated measurements, and TM, TB, and SR estimates were created using noise levels from worksites external to the current study. The bias, precision, accuracy, and absolute agreement of estimates created using the three techniques were evaluated by comparing estimated exposures with measured exposures. Trade mean estimates showed little bias, while neither the TM nor the SR techniques produced unbiased estimates, and the SR estimates showed the greatest bias of the three techniques. Accuracy was essentially equivalent among the three techniques. All three techniques showed poor agreement with measured exposures and were not highly correlated with each other. Estimates from the SR technique generally performed similarly to the TM and TB techniques. Methods to incorporate information from each technique into exposure estimates should be explored.

  3. Evaluation of power transfer efficiency for a high power inductively coupled radio-frequency hydrogen ion source

    Science.gov (United States)

    Jain, P.; Recchia, M.; Cavenago, M.; Fantz, U.; Gaio, E.; Kraus, W.; Maistrello, A.; Veltri, P.

    2018-04-01

    Neutral beam injection (NBI) for plasma heating and current drive is necessary for International Thermonuclear Experimental reactor (ITER) tokamak. Due to its various advantages, a radio frequency (RF) driven plasma source type was selected as a reference ion source for the ITER heating NBI. The ITER relevant RF negative ion sources are inductively coupled (IC) devices whose operational working frequency has been chosen to be 1 MHz and are characterized by high RF power density (˜9.4 W cm-3) and low operational pressure (around 0.3 Pa). The RF field is produced by a coil in a cylindrical chamber leading to a plasma generation followed by its expansion inside the chamber. This paper recalls different concepts based on which a methodology is developed to evaluate the efficiency of the RF power transfer to hydrogen plasma. This efficiency is then analyzed as a function of the working frequency and in dependence of other operating source and plasma parameters. The study is applied to a high power IC RF hydrogen ion source which is similar to one simplified driver of the ELISE source (half the size of the ITER NBI source).

  4. Radiofrequency in cosmetic dermatology.

    Science.gov (United States)

    Beasley, Karen L; Weiss, Robert A

    2014-01-01

    The demand for noninvasive methods of facial and body rejuvenation has experienced exponential growth over the last decade. There is a particular interest in safe and effective ways to decrease skin laxity and smooth irregular body contours and texture without downtime. These noninvasive treatments are being sought after because less time for recovery means less time lost from work and social endeavors. Radiofrequency (RF) treatments are traditionally titrated to be nonablative and are optimal for those wishing to avoid recovery time. Not only is there minimal recovery but also a high level of safety with aesthetic RF treatments. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Evaluation of HSP70 expression and DNA damage in cells of a human trophoblast cell line exposed to 1.8 GHz amplitude-modulated radiofrequency fields.

    Science.gov (United States)

    Valbonesi, Paola; Franzellitti, Silvia; Piano, Annamaria; Contin, Andrea; Biondi, Carla; Fabbri, Elena

    2008-03-01

    The aim of this study was to determine whether high-frequency electromagnetic fields (EMFs) could induce cellular effects. The human trophoblast cell line HTR-8/SVneo was used as a model to evaluate the expression of proteins (HSP70 and HSC70) and genes (HSP70A, B, C and HSC70) of the HSP70 family and the primary DNA damage response after nonthermal exposure to pulse-modulated 1817 MHz sinusoidal waves (GSM-217 Hz; 1 h; SAR of 2 W/kg). HSP70 expression was significantly enhanced by heat, which was applied as the prototypical stimulus. The HSP70A, B and C transcripts were differentially expressed under basal conditions, and they were all significantly induced above basal levels by thermal stress. Conversely, HSC70 protein and gene expression was not influenced by heat. Exposing HTR-8/SVneo cells to high-frequency EMFs did not change either HSP70 or HSC70 protein or gene expression. A significant increase in DNA strand breaks was caused by exposure to H(2)O(2), which was used as a positive stimulus; however, no effect was observed after exposure of cells to high-frequency EMFs. Overall, no evidence was found that a 1-h exposure to GSM-217 Hz induced a HSP70-mediated stress response or primary DNA damage in HTR-8/SVneo cells. Nevertheless, further investigations on trophoblast cell responses after exposure to GSM signals of different types and durations are needed.

  6. Evaluation of radiological exposure from Plowshare applications, 1967--1975

    International Nuclear Information System (INIS)

    Barton, C.J.; Kaye, S.V.

    1975-08-01

    A review of the highlights and accomplishments of the nine-year program, FY 1967-75, at ORNL on the evaluation of the radiological exposure from Plowshare applications is presented. Conclusions based on the studies summarized are given. Chronological lists of presentations, reports and open literature publications on the various investigations of the program are appended to the report. (auth)

  7. Mechano-transduction effect of shockwaves in the treatment of lumbar facet joint pain: comparative effectiveness evaluation of shockwave therapy, steroid injections and radiofrequency medial branch neurotomy.

    Science.gov (United States)

    Nedelka, Tomas; Nedelka, Jiri; Schlenker, Jakub; Hankins, Christopher; Mazanec, Radim

    2014-01-01

    Lumbar facet joints (FJ) is a common source of low back pain and contributes approximmately on one third of chronic low back pain. Medial branch radiofrequency neurotomy is considered as a gold standard in the treatment of facet joint pain. Corticosteroid injections have also presented effect in FJ pain. As an interventional procedures, they carry not-negligible risk of possible complications including infection, damage to nerve root or medial branch structures. Shockwave therapy (SWT) is a non-invasive method for treatment of various musculoskeletal disorders. Its effect is based on transduction of mechanical energy, transferred to cascade of various biochemical processes in target tissue. Its efficacy was proved in the treatment of different painful conditions. The efficacy of SWT was not yet studied in FJ pain. Aim of our work was to compare the efficacy of SWT against interventional treatment procedures - radiofrequency neurotomy and corticosteroid FJ injections. A retrospective study was done on 62 selected patients with unilateral chronic lumbar facet pain. There were 32 women and 30 men, divided into SWT group, corticosteroid injections group radiofrequency group. Nociceptive and neuropathic pain intensity and severity of pain were measured. Shockwave therapy had shown better longterm results compared to FJ injections group and little inferior efficacy compared to RMBN. We did not observe any adverse effects and complications in SWT group. Moreover, in SWT and RMBN groups, significant longterm improvement in daily activities limitation, was observed. SWT appears to be a safe and perspective option in the treatment of FJ pain with negligible side effects.

  8. Overview of UNSCEAR re-evaluation of occupational exposure

    International Nuclear Information System (INIS)

    Melo, Dunstana

    2008-01-01

    The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has re-evaluated the levels of occupational radiation exposure for two broad categories of sources: natural sources of radiation and man-made source of radiation. The latter one includes the practices from the nuclear fuel cycle, medical uses of radiation, industrial uses, military activities, and miscellaneous sources. The evaluation has been performed based on the data provided in response to the UNSCEAR Survey of Occupational Radiation Exposures and also data from the literature. In general, the reporting of exposures arising in the commercial nuclear fuel cycle is more complete than that of exposures arising from other uses of radiation. The figure for occupational exposure, for the periods 1995-1999 and 2000-2002, has changed compared to the estimates in the UNSCEAR 2000 Report. The collective effective dose resulting from exposures to natural sources (in excess of average levels of natural background) is estimated to be about 37 260 man Sv, about 3 times higher than the value estimated in the UNSCEAR 2000 Report. The worldwide average annual collective effective dose for the workers involved in the use of man-made sources of radiation is around 4 730 man Sv, about 2 times higher than the value estimated in the UNSCEAR 2000 Report. The medical uses of radiation contributes with about 75% of the collective effective dose; nuclear fuel cycles contributes with about 17% and industrial uses, military activities and all other categories of worker contribute with about 8% of the collective dose for man-made sources of radiation. In general the levels of occupational exposure have decreased: the average effective doses are decreasing over time for all practices, the collective effective doses have fallen for most of the practices; except for medical uses which is now estimated based on more realistic data of number of monitored workers. (author)

  9. Treatment of refractory idiopathic supraorbital neuralgia using percutaneous pulsed radiofrequency.

    Science.gov (United States)

    Luo, Fang; Lu, Jingjing; Ji, Nan

    2018-02-26

    No ideal therapeutic method currently exists for refractory idiopathic supraorbital neuralgia patients who don't respond to conservative therapy, including medications and nerve blocks. Pulsed radiofrequency is a neuromodulation technique that does not produce sequelae of nerve damage after treatment. However, the efficacy of percutaneous pulsed radiofrequency for the treatment of refractory idiopathic supraorbital neuralgia is still not clear. The purpose of our study was to evaluate the efficacy and safety of pulsed radiofrequency treatment of the supraorbital nerve for refractory supraorbital neuralgia patients. We prospectively investigated the long-term effects of ultrasound-guided percutaneous pulsed radiofrequency in the treatment of 22 refractory idiopathic supraorbital neuralgia patients. A reduction of verbal pain numerical rating scale score of more than 50% was used as the standard of effectiveness. The effectiveness rates at different time points within two years were calculated. After a single pulsed radiofrequency treatment, the effectiveness rate at one and three months was 77%, and the rates at six months, one year, and two years were 73%, 64%, and 50%, respectively. Except for a small portion of patients (23%) who experienced mild upper eyelid ecchymosis that gradually disappeared after approximately two weeks, no obvious complications were observed. In conclusion, the results of our study demonstrate that for patients with refractory idiopathic supraorbital neuralgia, percutaneous pulsed radiofrequency may be an effective and safe treatment choice. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  10. Systematic evaluation of observational methods assessing biomechanical exposures at work

    DEFF Research Database (Denmark)

    Takala, Esa-Pekka; Irmeli, Pehkonen; Forsman, Mikael

    2009-01-01

      Systematic evaluation of observational methods assessing biomechanical exposures at work   Esa-Pekka Takala 1, Irmeli Pehkonen 1, Mikael Forsman 2, Gert-Åke Hansson 3, Svend Erik Mathiassen 4, W. Patrick Neumann 5, Gisela Sjøgaard 6, Kaj Bo Veiersted 7, Rolf Westgaard 8, Jørgen Winkel 9   1...... University of Science and Technology, Trondheim, 9 University of Gothenburg and National Research Centre for the Working Environment, Copenhagen   The aim of this project was to identify and systematically evaluate observational methods to assess workload on the musculoskeletal system. Searches...... by sorting the methods according to the several items evaluated.   Numerous methods have been developed to assess physical workload (biomechanical exposures) in order to identify hazards leading to musculoskeletal disorders, to monitor the effects of ergonomic changes, and for research. No indvidual method...

  11. Evaluation of cumulative PCB exposure estimated by a job exposure matrix versus PCB serum concentrations

    Science.gov (United States)

    Ruder, Avima M.; Succop, Paul; Waters, Martha A.

    2015-01-01

    Although polychlorinated biphenyls (PCBs) have been banned in many countries for more than three decades, exposures to PCBs continue to be of concern due to their long half-lives and carcinogenic effects. In National Institute for Occupational Safety and Health studies, we are using semiquantitative plant-specific job exposure matrices (JEMs) to estimate historical PCB exposures for workers (n=24,865) exposed to PCBs from 1938 to 1978 at three capacitor manufacturing plants. A subcohort of these workers (n=410) employed in two of these plants had serum PCB concentrations measured at up to four times between 1976 and 1989. Our objectives were to evaluate the strength of association between an individual worker’s measured serum PCB levels and the same worker’s cumulative exposure estimated through 1977 with the (1) JEM and (2) duration of employment, and to calculate the explained variance the JEM provides for serum PCB levels using (3) simple linear regression. Consistent strong and statistically significant associations were observed between the cumulative exposures estimated with the JEM and serum PCB concentrations for all years. The strength of association between duration of employment and serum PCBs was good for highly chlorinated (Aroclor 1254/HPCB) but not less chlorinated (Aroclor 1242/LPCB) PCBs. In the simple regression models, cumulative occupational exposure estimated using the JEMs explained 14–24 % of the variance of the Aroclor 1242/LPCB and 22–39 % for Aroclor 1254/HPCB serum concentrations. We regard the cumulative exposure estimated with the JEM as a better estimate of PCB body burdens than serum concentrations quantified as Aroclor 1242/LPCB and Aroclor 1254/HPCB. PMID:23475397

  12. A 12-week clinical and instrumental study evaluating the efficacy of a multisource radiofrequency home-use device for wrinkle reduction and improvement in skin tone, skin elasticity, and dermal collagen content.

    Science.gov (United States)

    Sadick, Neil S; Harth, Yoram

    2016-12-01

    This study was performed in order to evaluate the safety and efficacy of a new handheld home-use multisource radiofrequency device on facial rejuvenation. Forty-seven male and female subjects were enrolled. All subjects received a NEWA ® 3DEEP ™ home-use device (EndyMed Medical, Caesarea, Israel) to be used on facial skin three times per week for the first four weeks and then reduced to two times per week for the following eight weeks. Assessments included expert clinical grading for efficacy, instrumental evaluation, image analysis, and photography. Forty-five subjects completed the study; all subjects reported the treatment to be painless with only mild erythema lasting up to 15 minutes post-treatment. No other adverse events were reported. Statistically significant improvements were noted in the appearance of marionette lines, skin brightness, elasticity, firmness, lift (facial), lift (jawline), texture/smoothness, tone, and radiance/luminosity by expert visual assessment. Statistically significant improvements in skin firmness and elasticity were found using a Cutometer MPA 580, as well as in collagen and hemoglobin content of the skin using a SIAscope. The results of this study indicate that the NEWA ® multisource radiofrequency home-use device is effective in self-administered skin rejuvenation.

  13. Conventional Radiofrequency Thermocoagulation vs Pulsed Radiofrequency Neuromodulation of Ganglion Impar in Chronic Perineal Pain of Nononcological Origin.

    Science.gov (United States)

    Usmani, Hammad; Dureja, G P; Andleeb, Roshan; Tauheed, Nazia; Asif, Naiyer

    2018-01-10

    Chronic nononcological perineal pain has been effectively managed by ganglion Impar block. Chemical neurolysis, cryoablation, and radiofrequency ablation have been the accepted methods of blockade. Recently, pulsed radiofrequency, a novel variant of conventional radiofrequency, has been used for this purpose. This was a prospective, randomized, double-blind study. Two different interventional pain management centers in India. To compare the efficacy of conventional radiofrequency and pulsed radiofrequency for gangliom Impar block. The patients were randomly allocated to one of two groups. In the conventional radiofrequency (CRF) group (N = 34), conventional radiofrequency ablation was done, and in the PRF pulsed radiofrequency (PRF) group (N = 31), pulsed radiofrequency ablation was done. After informed and written consent, fluoroscopy-guided ganglion Impar block was performed through the first intracoccygeal approach. The extent of pain relief was assessed by visual analog scale (VAS) at 24 hours, and at the first, third, and sixth weeks following the intervention. A questionnaire to evaluate subjective patient satisfaction was also used at each follow-up visit. In the CRF group, the mean VAS score decreased significantly from the baseline value at each follow-up visit. But in the PRF group, this decrease was insignificant except at 24-hour follow-up. Intergroup comparison also showed significantly better pain relief in the CRF group as compared with the PRF group. At the end of follow-up, 28 patients (82%) in the CRF group and four patients (13%) in the PRF group had excellent results, as assessed by the subjective patient satisfaction questionnaire. There was no complication in any patient of either study group, except for short-lived infection at the site of skin puncture in a few. Ganglion Impar block by conventional radiofrequency provided a significantly better quality of pain relief with no major side effects in patients with chronic

  14. Tinnitus and cell phones: the role of electromagnetic radiofrequency radiation.

    Science.gov (United States)

    Medeiros, Luisa Nascimento; Sanchez, Tanit Ganz

    2016-01-01

    Tinnitus is a multifactorial condition and its prevalence has increased on the past decades. The worldwide progressive increase of the use of cell phones has exposed the peripheral auditory pathways to a higher dose of electromagnetic radiofrequency radiation (EMRFR). Some tinnitus patients report that the abusive use of mobiles, especially when repeated in the same ear, might worsen ipsilateral tinnitus. The aim of this study was to evaluate the available evidence about the possible causal association between tinnitus and exposure to electromagnetic waves. A literature review was performed searching for the following keywords: tinnitus, electromagnetic field, mobile phones, radio frequency, and electromagnetic hypersensitivity. We selected 165 articles that were considered clinically relevant in at least one of the subjects. EMRFR can penetrate exposed tissues and safety exposure levels have been established. These waves provoke proved thermogenic effects and potential biological and genotoxic effects. Some individuals are more sensitive to electromagnetic exposure (electrosensitivity), and thus, present earlier symptoms. There may be a common pathophysiology between this electrosensitivity and tinnitus. There are already reasonable evidences to suggest caution for using mobile phones to prevent auditory damage and the onset or worsening of tinnitus. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  15. Tinnitus and cell phones: the role of electromagnetic radiofrequency radiation

    Directory of Open Access Journals (Sweden)

    Luisa Nascimento Medeiros

    2016-02-01

    Full Text Available ABSTRACT INTRODUCTION: Tinnitus is a multifactorial condition and its prevalence has increased on the past decades. The worldwide progressive increase of the use of cell phones has exposed the peripheral auditory pathways to a higher dose of electromagnetic radiofrequency radiation (EMRFR. Some tinnitus patients report that the abusive use of mobiles, especially when repeated in the same ear, might worsen ipsilateral tinnitus. OBJECTIVE: The aim of this study was to evaluate the available evidence about the possible causal association between tinnitus and exposure to electromagnetic waves. METHODS: A literature review was performed searching for the following keywords: tinnitus, electromagnetic field, mobile phones, radio frequency, and electromagnetic hypersensitivity. We selected 165 articles that were considered clinically relevant in at least one of the subjects. RESULTS: EMRFR can penetrate exposed tissues and safety exposure levels have been established. These waves provoke proved thermogenic effects and potential biological and genotoxic effects. Some individuals are more sensitive to electromagnetic exposure (electrosensitivity, and thus, present earlier symptoms. There may be a common pathophysiology between this electrosensitivity and tinnitus. CONCLUSION: There are already reasonable evidences to suggest caution for using mobile phones to prevent auditory damage and the onset or worsening of tinnitus.

  16. Prospective Internally Controlled Blind Reviewed Clinical Evaluation of Cryolipolysis Combined With Multipolar Radiofrequency andVaripulseTechnology for Enhanced Subject Results in Circumferential Fat Reduction and Skin Laxity of the Flanks.

    Science.gov (United States)

    Few, Julius; Gold, Michael; Sadick, Neil

    2016-11-01

    Increasing demand for non-invasive skin tightening and body contouring procedures has led to several technological in- novations in energy-based devices such as ultrasound, radiofrequency and cryolipolysis. An emerging trend in the eld is to evaluate whether combination therapies for skin laxity/body contouring using energy-based devices can deliver superior clinical results and patient satisfaction. As such, the objective of this prospective, internal-controlled, blind clinical study was to assess the safety and efficacy of cryolipolysis followed by multipolar radiofrequency with pulsed electromagnetic elds (PEMF) and adjustable pulsed suction for the treatment of skin laxity in the flanks. Ten subjects with focal adiposities in the anks were enrolled in the study. All subjects received one session of cryolipolysis treatment and after randomization received two sessions of radiofrequency with PEMF (spaced two weeks apart), followed by another two sessions of radiofrequency with PEMF and adjustable pulsed suction (spaced two weeks apart). Clinical photography was used to monitor the subject's results at baseline, one week, three, and six months post treatment. Blinded reviewers and the treating inves- tigator assessed the clinical outcomes using the Global Aesthetic Improvement (GAI) scale. Side effects were recorded at every visit and patient satisfaction was noted at the one week, three and six-month follow-up using a 5-scale subject satisfaction assessment questionnaire. Analysis of the blinded investigator ratings demonstrated statistical significant enhanced skin laxity mean improvement of 1 grade on the GAI scale in subject treated with the combination treatment (cryolipolysis+RF/PEMF/suction) compared with the cryolipolysis treatment alone. The unblinded investigator GAI ratings also showed enhanced (20%) mean improvement of laxity in the combination treated subjects versus those receiving cryolipolysis alone. Over half of the participants reported

  17. Radiofrequency attenuator and method

    Science.gov (United States)

    Warner, Benjamin P [Los Alamos, NM; McCleskey, T Mark [Los Alamos, NM; Burrell, Anthony K [Los Alamos, NM; Agrawal, Anoop [Tucson, AZ; Hall, Simon B [Palmerston North, NZ

    2009-01-20

    Radiofrequency attenuator and method. The attenuator includes a pair of transparent windows. A chamber between the windows is filled with molten salt. Preferred molten salts include quarternary ammonium cations and fluorine-containing anions such as tetrafluoroborate (BF.sub.4.sup.-), hexafluorophosphate (PF.sub.6.sup.-), hexafluoroarsenate (AsF.sub.6.sup.-), trifluoromethylsulfonate (CF.sub.3SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3SO.sub.2).sub.2N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3CF.sub.2SO.sub.2).sub.2N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3SO.sub.2).sub.3C.sup.-). Radicals or radical cations may be added to or electrochemically generated in the molten salt to enhance the RF attenuation.

  18. Effects of 1.8 GHz Radiofrequency Fields on the Emotional Behavior and Spatial Memory of Adolescent Mice

    OpenAIRE

    Zhang, Jun-Ping; Zhang, Ke-Ying; Guo, Ling; Chen, Qi-Liang; Gao, Peng; Wang, Tian; Li, Jing; Guo, Guo-Zhen; Ding, Gui-Rong

    2017-01-01

    The increasing use of mobile phones by teenagers has raised concern about the cognitive effects of radiofrequency (RF) fields. In this study, we investigated the effects of 4-week exposure to a 1.8 GHz RF field on the emotional behavior and spatial memory of adolescent male mice. Anxiety-like behavior was evaluated by open field test (OFT) and elevated plus maze (EPM) test, while depression-like behavior was evaluated by sucrose preference test (SPT), tail suspension test (TST) and forced swi...

  19. HANFORD CHEMICAL VAPORS WORKER CONCERNS and EXPOSURE EVALUATION

    International Nuclear Information System (INIS)

    ANDERSON, T.J.

    2006-01-01

    Chemical vapor emissions from underground hazardous waste storage tanks on the Hanford site in eastern Washington State are a potential concern because workers enter the tank farms on a regular basis for waste retrievals, equipment maintenance, and surveillance. Tank farm contractors are in the process of retrieving all remaining waste from aging single-shell tanks, some of which date to World War II, and transferring it to newer double-shell tanks. During the waste retrieval process, tank farm workers are potentially exposed to fugitive chemical vapors that can escape from tank headspaces and other emission points. The tanks are known to hold more than 1,500 different species of chemicals, in addition to radionuclides. Exposure assessments have fully characterized the hazards from chemical vapors in half of the tank farms. Extensive sampling and analysis has been done to characterize the chemical properties of hazardous waste and to evaluate potential health hazards of vapors at the ground surface, where workers perform maintenance and waste transfer activities. Worker concerns. risk communication, and exposure assessment are discussed, including evaluation of the potential hazards of complex mixtures of chemical vapors. Concentrations of vapors above occupational exposure limits-(OEL) were detected only at exhaust stacks and passive breather filter outlets. Beyond five feet from the sources, vapors disperse rapidly. No vapors have been measured above 50% of their OELs more than five feet from the source. Vapor controls are focused on limited hazard zones around sources. Further evaluations of vapors include analysis of routes of exposure and thorough analysis of nuisance odors

  20. Radiofrequency electromagnetic fields in the Cookridge area of Leeds

    CERN Document Server

    Fuller, K; Judd, P M; Lowe, A J; Shaw, J

    2002-01-01

    On the 8 and 9 May 2002 representatives of the National Radiological Protection Board (NRPB) performed a radiofrequency electromagnetic field survey in the Cookridge area of Leeds in order to assess exposure to radio signals from transmitters mounted on a water tower/a lattice tower and a radio station tower. Guidelines on limiting exposure to radio signals have been published by NRPB and the International Commission on Non-Ionizing Radiation Protection (ICNIRP). These guidelines are designed to prevent established adverse effects on human health. During this survey, the total exposures due to all radio signals from 30 MHz to 18000 MHz (18 GHz) were measured. This frequency range was chosen as it includes mobile phone base station transmissions, which are at around 900 and 1800 MHz and super high frequency (SHF) transmissions from most of the large microwave dish antennas mounted on the towers. In addition, other major sources of radiofrequency electromagnetic fields in the environment such as broadcast radio...

  1. Ver reactor pressure vessel neutron exposure evaluation and monitoring

    International Nuclear Information System (INIS)

    Osmera, B.

    1992-01-01

    The surveillance neutron exposure monitoring system In VVER-440, V 213 series, consists of 54 Fe(n,p), 63 Cu(n,α and 93 Nb(n,n) detectors. The Fe detector is loaded for one year Cone fuel cycle) Irradiation only. The evaluation of the neutron monitor results including transformation to the critical locations of the reactor pressure vessel (RPV) can be based on the direct estimations of the neutron spectra and led factors (and other important space energy indices) in the mock-up experiments carried out. in the LR-0 experimental reactor, N.R.I. Rez. Because of high acceleration factor (about 11 for neutrons with energy above 0.5 MeV) the specimens are pulled out within five years of VVER-440 operation. After that the ex-vessel monitoring should be applied for RPV exposure determination. A recommended procedure (guide) for the RPV neutron exposure evaluation has been completed recently. All previous experimental data (the surveillance and ex-vessel monitors, I.R-0 mock-up measurements) have been revised arid reevaluated using the IRDF-90 (IAEA) cross section data. A brief review of this work is presented in the paper. Some comments relating to the RPV dosimetry of VVER-440, series 230, and VVER-1000 reactors are also done. (author)

  2. Medication Exposure in Pregnancy Risk Evaluation Program (MEPREP).

    Science.gov (United States)

    Davis, Robert L

    2010-01-01

    Knowledge about safe medication use during pregnancy is limited, yet about two of every three women take at least one prescription medication during pregnancy, furthermore, there is a lack of rigorous studies evaluating birth outcomes associated with in utero exposure to medications. The Medication Exposure in Pregnancy Risk Evaluation Program (MEPREP) is intended to provide a mechanism for collaborative pharmacoepidemiological research to address the safety of pharmaceutical product exposure during pregnancy, through the development of standardized data requirements and of the necessary data linkages of mother-infant pairs to conduct multi-site investigations. This presentation will describe the program, the types of data collected, and progress to date. The current MEPREP population includes female health plan members of 11 distinct health management entities within three research centres who have delivered an infant between January 1, 2001 and December 31, 2007, along with the administrative and birth certificate data on over one million children linked to mothers. There is information on all the medications those mothers took, as well as most of the outcomes of the babies. One of the benefits of this dataset is the information that could be investigated, such as birth weight, fetal growth, congenital anomalies, perinatal conditions, etc., against various demographics of the women in the dataset. The population size within the dataset suggests that various parameters could be studied with at least a modest degree of power.

  3. Sucrose modulation of radiofrequency-induced heating rates and cell death.

    Science.gov (United States)

    Pulikkathara, Merlyn; Mark, Colette; Kumar, Natasha; Zaske, Ana Maria; Serda, Rita E

    2017-09-01

    Applied radiofrequency (RF) energy induces hyperthermia in tissues, facilitating vascular perfusion This study explores the impact of RF radiation on the integrity of the luminal endothelium, and then predominately explores the impact of altering the conductivity of biologically-relevant solutions on RF-induced heating rates and cell death. The ability of cells to survive high sucrose (i.e. hyperosmotic conditions) to achieve lower conductivity as a mechanism for directing hyperthermia is evaluated. RF radiation was generated using a capacitively-coupled radiofrequency system operating at 13.56 MHz. Temperatures were recorded using a FLIR SC 6000 infrared camera. RF radiation reduced cell-to-cell connections among endothelial cells and altered cell morphology towards a more rounded appearance at temperatures reported to cause in vivo vessel deformation. Isotonic solutions containing high sucrose and low levels of NaCl displayed low conductivity and faster heating rates compared to high salt solutions. Heating rates were positively correlated with cell death. Addition of sucrose to serum similarly reduced conductivity and increased heating rates in a dose-dependent manner. Cellular proliferation was normal for cells grown in media supplemented with 125 mM sucrose for 24 hours or for cells grown in 750 mM sucrose for 10 minutes followed by a 24 h recovery period. Sucrose is known to form weak hydrogen bonds in fluids as opposed to ions, freeing water molecules to rotate in an oscillating field of electromagnetic radiation and contributing to heat induction. The ability of cells to survive temporal exposures to hyperosmotic (i.e. elevated sucrose) conditions creates an opportunity to use sucrose or other saccharides to selectively elevate heating in specific tissues upon exposure to a radiofrequency field.

  4. Radiofrequency for the Treatment of Lumbar Radicular Pain: Impact on Surgical Indications.

    Science.gov (United States)

    Trinidad, José Manuel; Carnota, Ana Isabel; Failde, Inmaculada; Torres, Luis Miguel

    2015-01-01

    Study Design. Quasiexperimental study. Objective. To investigate whether radiofrequency treatment can preclude the need for spinal surgery in both the short term and long term. Background. Radiofrequency is commonly used to treat lumbosacral radicular pain. Only few studies have evaluated its effects on surgical indications. Methods. We conducted a quasiexperimental study of 43 patients who had been scheduled for spinal surgery. Radiofrequency was indicated for 25 patients. The primary endpoint was the decision of the patient to reject spinal surgery 1 month and 1 year after treatment (pulsed radiofrequency of dorsal root ganglion, 76%; conventional radiofrequency of the medial branch, 12%; combined technique, 12%). The primary endpoint was the decision of the patient to reject spinal surgery 1 month and 1 year after treatment. In addition, we also evaluated adverse effects, ODI, NRS. Results. We observed after treatment with radiofrequency 80% of patients rejected spinal surgery in the short term and 76% in the long term. We conclude that radiofrequency is a useful treatment strategy that can achieve very similar outcomes to spinal surgery. Patients also reported a very high level of satisfaction (84% satisfied/very satisfied). We also found that optimization of the electrical parameters of the radiofrequency improved the outcome of this technique.

  5. Radiofrequency for the Treatment of Lumbar Radicular Pain: Impact on Surgical Indications

    Directory of Open Access Journals (Sweden)

    José Manuel Trinidad

    2015-01-01

    Full Text Available Study Design. Quasiexperimental study. Objective. To investigate whether radiofrequency treatment can preclude the need for spinal surgery in both the short term and long term. Background. Radiofrequency is commonly used to treat lumbosacral radicular pain. Only few studies have evaluated its effects on surgical indications. Methods. We conducted a quasiexperimental study of 43 patients who had been scheduled for spinal surgery. Radiofrequency was indicated for 25 patients. The primary endpoint was the decision of the patient to reject spinal surgery 1 month and 1 year after treatment (pulsed radiofrequency of dorsal root ganglion, 76%; conventional radiofrequency of the medial branch, 12%; combined technique, 12%. The primary endpoint was the decision of the patient to reject spinal surgery 1 month and 1 year after treatment. In addition, we also evaluated adverse effects, ODI, NRS. Results. We observed after treatment with radiofrequency 80% of patients rejected spinal surgery in the short term and 76% in the long term. We conclude that radiofrequency is a useful treatment strategy that can achieve very similar outcomes to spinal surgery. Patients also reported a very high level of satisfaction (84% satisfied/very satisfied. We also found that optimization of the electrical parameters of the radiofrequency improved the outcome of this technique.

  6. Measurement of radiofrequency fields

    International Nuclear Information System (INIS)

    Leonowich, J.A.

    1992-05-01

    We are literally surrounded by radiofrequency (RFR) and microwave radiation, from both natural and man-made sources. The identification and control of man-made sources of RFR has become a high priority of radiation safety professionals in recent years. For the purposes of this paper, we will consider RFR to cover the frequencies from 3 kHz to 300 MHz, and microwaves from 300 MHz to 300 GHz, and will use the term RFR interchangeably to describe both. Electromagnetic radiation and field below 3 kHz is considered Extremely Low Frequency (ELF) and will not be discussed in this paper. Unlike x- and gamma radiation, RFR is non-ionizing. The energy of any RFR photon is insufficient to produce ionizations in matter. The measurement and control of RFR hazards is therefore fundamentally different from ionizing radiation. The purpose of this paper is to acquaint the reader with the fundamental issues involved in measuring and safely using RFR fields. 23 refs

  7. Treatment of acne vulgaris with fractional radiofrequency microneedling.

    Science.gov (United States)

    Kim, Sang Tae; Lee, Kang Hoon; Sim, Hyung Jun; Suh, Kee Suck; Jang, Min Soo

    2014-07-01

    Fractional radiofrequency microneedling is a novel radiofrequency technique that uses insulated microneedles to deliver energy to the deep dermis at the point of penetration without destruction of the epidermis. It has been used for the treatment of various dermatological conditions including wrinkles, atrophic scars and hypertrophic scars. There have been few studies evaluating the efficacy of fractional radiofrequency microneedling in the treatment of acne, and none measuring objective parameters like the number of inflammatory and non-inflammatory acne lesions or sebum excretion levels. The safety and efficacy of fractional radiofrequency microneedling in the treatment of acne vulgaris was investigated. In a prospective clinical trial, 25 patients with moderate to severe acne were treated with fractional radiofrequency microneedling. The procedure was carried out three times at 1-month intervals. Acne lesion count, subjective satisfaction score, sebum excretion level and adverse effects were assessed at baseline and at 4, 8 and 12 weeks after the first treatment as well as 4, 8 and 12 weeks after the last treatment. Number of acne lesions (inflammatory and non-inflammatory) decreased. Sebum excretion and subjective satisfaction were more favorable at every time point compared with the baseline values (P acne vulgaris. © 2014 Japanese Dermatological Association.

  8. Comparative evaluation of oxygen-ozone therapy and combined use of oxygen-ozone therapy with percutaneous intradiscal radiofrequency thermocoagulation for the treatment of lumbar disc herniation.

    Science.gov (United States)

    Gautam, Sujeet; Rastogi, V; Jain, Ankur; Singh, A P

    2011-01-01

    To compare the efficacy of oxygen-ozone therapy and the combined use of oxygen-ozone therapy with percutaneous intradiscal radiofrequency thermocoagulation (PIRFT) for the treatment of contained lumbar disc herniation. Ninety-one adult patients with low back pain secondary to contained lumbar disc herniation were randomly assigned into two groups. Ozone group received intradiscal oxygen-ozone therapy (4 to 7 mL of oxygen ozone mixture); ozone-PIRFT group received a combination of oxygen-ozone therapy with PIRFT (radiofrequency lesioning at 80°C for 360 s). Primary outcome measures included a visual analog scale (VAS) for pain and the Oswestry disability index (ODI). Secondary outcome measures included pain relief, reduction of analgesic consumption, and patient's satisfaction. Clinical assessment of these outcome measures was performed at 2 weeks, 1 month, 3 months, 6 months, and 1 year after the procedure. VAS scores and ODI were significantly decreased by both ozone and ozone-PIRFT when compared with the baseline values at all points of follow-up; however, ozone-PIRFT produced a significant reduction in the VAS scores and ODI when compared to ozone at 2 weeks, 1 month, 3 months, 6 months, and 1 year follow-up. Ozone-PIRFT also resulted in a significant change in all secondary measures at all points of follow-up, as compared with the ozone group. Ozone-PIRFT is more efficacious than ozone alone in reducing pain scores, analgesic consumption, improving functional outcome, and satisfaction of patients with contained lumbar disc herniation. © 2010 World Institute of Pain.

  9. Analysis of estimation of electromagnetic dosimetric values from non-ionizing radiofrequency fields in conventional road vehicle environments.

    Science.gov (United States)

    Aguirre, Erik; Iturri, Peio Lopez; Azpilicueta, Leire; de Miguel-Bilbao, Silvia; Ramos, Victoria; Gárate, Uxue; Falcone, Francisco

    2015-03-01

    A high number of wireless technologies can be found operating in vehicular environments with the aim of offering different services. The dosimetric evaluation of this kind of scenarios must be performed in order to assess their compatibility with current exposure limits. In this work, a dosimetric evaluation inside a conventional car is performed, with the aid of an in-house 3D Ray Launching computational code, which has been compared with measurement results of wireless sensor networks located inside the vehicle. These results can aid in an adequate assessment of human exposure to non-ionizing radiofrequency fields, taking into account the impact of the morphology and the topology of the vehicle for current as well as for future exposure limits.

  10. Rapid growth of left atrial myxoma after radiofrequency ablation.

    Science.gov (United States)

    Rubio Alvarez, José; Martinez de Alegria, Anxo; Sierra Quiroga, Juan; Adrio Nazar, Belen; Rubio Taboada, Carola; Martinez Comendador, José Manuel

    2013-01-01

    Atrial myxoma is the most common benign tumor of the heart, but its appearance after radiofrequency ablation is very rare. We report a case in which an asymptomatic, rapidly growing cardiac myxoma arose in the left atrium after radiofrequency ablation. Two months after the procedure, cardiovascular magnetic resonance, performed to evaluate the right ventricular anatomy, revealed a 10 × 10-mm mass (assumed to be a thrombus) attached to the patient's left atrial septum. Three months later, transthoracic echocardiography revealed a larger mass, and the patient was diagnosed with myxoma. Two days later, a 20 × 20-mm myxoma weighing 37 g was excised. To our knowledge, the appearance of an atrial myxoma after radiofrequency ablation has been reported only once before. Whether tumor development is related to such ablation or is merely a coincidence is uncertain, but myxomas have developed after other instances of cardiac trauma.

  11. The radon in Corsica: evaluation of exposure and associated risks

    International Nuclear Information System (INIS)

    2006-02-01

    The average level found in Corsica is superior to that one found in France. On the basis of the results of it campaign I.R.S.N.-D.G.S., the French average is of 90 Bq.m 3 against 197 Bq.m 3 for Corsica. The risk of dying from a lung cancer attributable to the radon was estimated at 13 % in France. The evaluation of risk led on Corsica shows a risk attributable to the radon included between 21.5 and 28 %.This evaluation of risk is only a stage. It is important to arrest better the exposure to the radon of the Corsican population. For a good estimation of the levels of radon and thus the impact of this one, additional measures are necessary. The results of the data analysis of exposure allow to guide the choice of the new measures: a campaign on the season effect in Corsica and a completion of the measures in housing are two main axes.Seen the importance of the interaction between the tobacco and the radon, a good estimation of the tobacco customs in Corsica and its evolution in the time seems essential to estimate indeed the impact of the radon in this region. (N.C.)

  12. Developmental exposure to fenproporex: reproductive and morphological evaluation.

    Science.gov (United States)

    Moreira, C Q; Faria, M J S S; Baroneza, J E; Oliveira, R J; Moreira, E G

    2005-08-01

    This study was designed to evaluate the maternal toxicity and teratogenicity of fenproporex, one of the most widely-used anorectic drugs in many countries, including Brazil. Three periods of exposure were evaluated: (a) 30 days before mating; (b) from gestational day (GD) 0 to 14; and (c) 30 days before mating and during pregnancy, until GD 14. Female mice from experimental groups received, by gavage, 15 mg/kg of fenproporex. Treatment with fenproporex increased ambulation of dams in the open-field test and did not influence the mobility in the forced-swimming test. There was no significant difference in maternal weight gain between the controls and fenproporex-treated groups, although fenproporex treatment reduced the gravid uterus weight. No significant difference was observed in postimplantation loss, fetal viability and sex ratio. In addition, this compound did not impair intra-uterine growth. The reduction in the number of implantations in the groups receiving fenproporex indicates that this drug may have an adverse effect on implantation. Fenproporex treatment also increased the number of fetuses presenting small kidneys and cervical ribs. The present results indicate that fenproporex, in the dose and exposure periods tested, appears to exhibit a low maternal toxicity and teratogenic potential in mice.

  13. Radiofrequency ablation as initial therapy in paroxysmal atrial fibrillation

    DEFF Research Database (Denmark)

    Walfridsson, H; Walfridsson, U; Nielsen, J Cosedis

    2015-01-01

    AIMS: The Medical ANtiarrhythmic Treatment or Radiofrequency Ablation in Paroxysmal Atrial Fibrillation (MANTRA-PAF) trial assessed the long-term efficacy of an initial strategy of radiofrequency ablation (RFA) vs. antiarrhythmic drug therapy (AAD) as first-line treatment for patients with PAF....... In this substudy, we evaluated the effect of these treatment modalities on the Health-Related Quality of Life (HRQoL) and symptom burden of patients at 12 and 24 months. METHODS AND RESULTS: During the study period, 294 patients were enrolled in the MANTRA-PAF trial and randomized to receive AAD (N = 148) or RFA...

  14. New-generation radiofrequency technology.

    Science.gov (United States)

    Krueger, Nils; Sadick, Neil S

    2013-01-01

    Radiofrequency (RF) technology has become a standard treatment in aesthetic medicine with many indications due to its versatility, efficacy, and safety. It is used worldwide for cellulite reduction; acne scar revision; and treatment of hypertrophic scars and keloids, rosacea, and inflammatory acne in all skin types. However, the most common indication for RF technology is the nonablative tightening of tissue to improve skin laxity and reduce wrinkles. Radiofrequency devices are classified as unipolar, bipolar, or multipolar depending on the number of electrodes used. Additional modalities include fractional RF; sublative RF; phase-controlled RF; and combination RF therapies that apply light, massage, or pulsed electromagnetic fields (PEMFs). This article reviews studies and case series on these devices. Radiofrequency technology for aesthetic medicine has seen rapid advancements since it was used for skin tightening in 2003. Future developments will continue to keep RF technology at the forefront of the dermatologist's armamentarium for skin tightening and rejuvenation.

  15. Cooled radiofrequency denervation for treatment of sacroiliac joint pain: two-year results from 20 cases

    Science.gov (United States)

    Ho, Kok-Yuen; Hadi, Mohamed Abdul; Pasutharnchat, Koravee; Tan, Kian-Hian

    2013-01-01

    Background Sacroiliac joint pain is a common cause of chronic low back pain. Different techniques for radiofrequency denervation of the sacroiliac joint have been used to treat this condition. However, results have been inconsistent because the variable sensory supply to the sacroiliac joint is difficult to disrupt completely using conventional radiofrequency. Cooled radiofrequency is a novel technique that uses internally cooled radiofrequency probes to enlarge lesion size, thereby increasing the chance of completely denervating the sacroiliac joint. The objective of this study was to evaluate the efficacy of cooled radiofrequency denervation using the SInergy™ cooled radiofrequency system for sacroiliac joint pain. Methods The charts of 20 patients with chronic sacroiliac joint pain who had undergone denervation using the SInergy™ cooled radiofrequency system were reviewed at two years following the procedure. Outcome measures included the Numeric Rating Scale for pain intensity, Patient Global Impression of Change, and Global Perceived Effect for patient satisfaction. Results Fifteen of 20 patients showed a significant reduction in pain (a decrease of at least three points on the Numeric Rating Scale). Mean Numeric Rating Scale for pain decreased from 7.4 ± 1.4 to 3.1 ± 2.5, mean Patient Global Impression of Change was “improved” (1.4 ± 1.5), and Global Perceived Effect was reported to be positive in 16 patients at two years following the procedure. Conclusion Cooled radiofrequency denervation showed long-term efficacy for up to two years in the treatment of sacroiliac joint pain. PMID:23869175

  16. Radiofrequency power deposition during magnetic resonance diagnostic examinations

    International Nuclear Information System (INIS)

    Grandolfo, M.; Vecchia, P.

    1988-01-01

    Magnetic Resonance Imaging and Spectroscopy (MRI, MRS) require that subjects be exposed to radiofrequency field, and the corresponding energy absorption leads to tissue heating. The main question, thus, to be considered in connection to safety and health aspects is related to the specific absorption rate (SAR) in the imaged subject and the exposure durations which might put a practical limit on the pulse sequence which can be used. In this paper some models and experimental results for radiofrequency power deposition in MRI and MRS machines are reviewed. Models show that energy dissipation is a function of the frequency, RF incident power density, exposure duration, coupling between the RF coil and the subject, and several properties of the exposed tissue, including conductivity, dielectric constant, specific gravity, size, and orientation relative to the field polarization. The ability of the body's normal thermoregulatory responses to cope with high levels of RF energy deposition must be also taken into account

  17. The Influence of Radiofrequency Electromagnetic Radiation on the Platelet Aggregation

    Directory of Open Access Journals (Sweden)

    Gulzoda M. Khamidova

    2014-09-01

    Full Text Available The purpose of this study was to examine the impact of radiofrequency electromagnetic fields (RF-EMFs on platelet aggregation (PA in individuals working for a long time under a direct and continuous RF-EMF exposure. We examined 119 persons aged from 22 to 65 years. In individuals working under the direct and constant exposure to RF-EMFs, the various changes of PA with a predominance of hyperaggregation are detected. The dependence of the changes in the indicators of PA on length of work in conditions of RF-EMF exposure is determined.

  18. Developing and evaluating distributions for probabilistic human exposure assessments

    Energy Technology Data Exchange (ETDEWEB)

    Maddalena, Randy L.; McKone, Thomas E.

    2002-08-01

    This report describes research carried out at the Lawrence Berkeley National Laboratory (LBNL) to assist the U. S. Environmental Protection Agency (EPA) in developing a consistent yet flexible approach for evaluating the inputs to probabilistic risk assessments. The U.S. EPA Office of Emergency and Remedial Response (OERR) recently released Volume 3 Part A of Risk Assessment Guidance for Superfund (RAGS), as an update to the existing two-volume set of RAGS. The update provides policy and technical guidance on performing probabilistic risk assessment (PRA). Consequently, EPA risk managers and decision-makers need to review and evaluate the adequacy of PRAs for supporting regulatory decisions. A critical part of evaluating a PRA is the problem of evaluating or judging the adequacy of input distributions PRA. Although the overarching theme of this report is the need to improve the ease and consistency of the regulatory review process, the specific objectives are presented in two parts. The objective of Part 1 is to develop a consistent yet flexible process for evaluating distributions in a PRA by identifying the critical attributes of an exposure factor distribution and discussing how these attributes relate to the task-specific adequacy of the input. This objective is carried out with emphasis on the perspective of a risk manager or decision-maker. The proposed evaluation procedure provides consistency to the review process without a loss of flexibility. As a result, the approach described in Part 1 provides an opportunity to apply a single review framework for all EPA regions and yet provide the regional risk manager with the flexibility to deal with site- and case-specific issues in the PRA process. However, as the number of inputs to a PRA increases, so does the complexity of the process for calculating, communicating and managing risk. As a result, there is increasing effort required of both the risk professionals performing the analysis and the risk manager

  19. A different approach to evaluating health effects from radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Bond, V.P.; Sondhaus, C.A.; Feinendegen, L.E.

    1988-01-01

    Absorbed dose D is shown to be a composite variable, the product of the fraction of cells hit (I/sub H/) and the mean /open quotes/dose/close quotes/ (hit size) /ovr z/ to those cells. D is suitable for use with high level (HLE) to radiation and its resulting acute organ effects because, since I/sub H/ = 1.0, D approximates closely enough the mean energy density in the cell as well as in the organ. However, with low-level exposure (LLE) to radiation and its consequent probability of cancer induction from a single cell, stochastic delivery of energy to cells results in a wide distribution of hit sizes z, and the expected mean value, /ovr z/, is constant with exposure. Thus, with LLE, only I/sub H/ varies with D so that the apparent proportionality between /open quotes/dose/close quotes/ and the fraction of cells transformed is misleading. This proportionality therefore does not mean that any (cell) dose, no matter how small, can be lethal. Rather, it means that, in the exposure of a population of individual organisms consisting of the constituent relevant cells, there is a small probabililty of particle-cell interactions which transfer energy. The probability of a cell transforming and initiating a cancer can only be greater than zero if the hit size (/open quotes/dose of energy/close quotes/) to the cell is large enough. Otherwise stated, if the /open quotes/dose/close quotes/ is defined at the proper level of biological organization, namely, the cell and not the organ, only a large dose z to that cell is effective. The above precepts are utilized to develop a drastically different approach to evaluation oif risk from LLE, that holds promise of obviating any requirement for the components of the present system: absorbed organ dose, LET, a standard radiation, REB(Q), dose equivalent and rem. 12 refs., 11 figs.

  20. Genetic effects of radiofrequency radiation (RFR)

    International Nuclear Information System (INIS)

    Verschaeve, L.

    2005-01-01

    The possible effects of radiofrequency (RF) exposure on the genetic material of cells are considered very important since damage to the DNA of somatic cells can be linked to cancer development or cell death whereas damage to germ cells can lead to genetic damage in next and subsequent generations. This is why the scientific literature reports many investigations on the subject. According to a number of review papers, the conclusion so far is that there is little evidence that RFR is directly mutagenic and that adverse effects that were reported in some of the papers are predominantly the result of hyperthermia. Yet, some subtle indirect effects on DNA replication and/or transcription of genes under relatively restricted exposure conditions cannot be ruled out. Furthermore, the possibility of combined effects of RFR with environmental carcinogens/mutagens merits further attention. The present paper takes into account more recent investigations but the conclusion remains the same. A majority of studies report no increased (cyto)genetic damage but yet, a considerable number of investigations do. However, many studies were not sufficiently characterized, are therefore difficult to replicate and cannot be compared to others. Experimental protocols were very different from one study to another and investigations from a single laboratory were very often limited in the sample size or number of cells investigated, preventing a robust statistical analysis. Subtle, but significant differences between RFR-exposed and sham-exposed cells cannot be found in such conditions. For the above reasons, it was concluded at a workshop in Loewenstein (November 2002) that further investigations by individual laboratories most probably will not add much to the discussion of radiofrequency radiation (RFR) genotoxicity. Large, well coordinated, international collaborative studies involving participation of several experienced scientists are considered an alternative of uttermost importance

  1. Genetic effects of radiofrequency radiation (RFR).

    Science.gov (United States)

    Verschaeve, L

    2005-09-01

    The possible effects of radiofrequency (RF) exposure on the genetic material of cells are considered very important since damage to the DNA of somatic cells can be linked to cancer development or cell death whereas damage to germ cells can lead to genetic damage in next and subsequent generations. This is why the scientific literature reports many investigations on the subject. According to a number of review papers, the conclusion so far is that there is little evidence that RFR is directly mutagenic and that adverse effects that were reported in some of the papers are predominantly the result of hyperthermia. Yet, some subtle indirect effects on DNA replication and/or transcription of genes under relatively restricted exposure conditions cannot be ruled out. Furthermore, the possibility of combined effects of RFR with environmental carcinogens/mutagens merits further attention. The present paper takes into account more recent investigations but the conclusion remains the same. A majority of studies report no increased (cyto)genetic damage but yet, a considerable number of investigations do. However, many studies were not sufficiently characterized, are therefore difficult to replicate and cannot be compared to others. Experimental protocols were very different from one study to another and investigations from a single laboratory were very often limited in the sample size or number of cells investigated, preventing a robust statistical analysis. Subtle, but significant differences between RFR-exposed and sham-exposed cells cannot be found in such conditions. For the above reasons, it was concluded at a workshop in Löwenstein (November 2002) that further investigations by individual laboratories most probably will not add much to the discussion of radiofrequency radiation (RFR) genotoxicity. Large, well coordinated, international collaborative studies involving participation of several experienced scientists are considered an alternative of uttermost importance

  2. CT-guided radiofrequency ablation of osteoid osteoma using a novel battery-powered drill

    Energy Technology Data Exchange (ETDEWEB)

    Schnapauff, Dirk; Streitparth, Florian; Wieners, Gero; Collettini, Federico; Hamm, Bernd; Gebauer, Bernhard [Charite Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany); Joehrens, Korinna [Charite Universitaetsmedizin Berlin, Department of Pathology, Berlin (Germany)

    2015-05-01

    To evaluate the use of a novel battery-powered drill, enabling specimen requirement while drilling, in radiofrequency ablation of osteoid osteoma as an alternative to conventional orthopedic drills. Between 2009 and 2013, altogether 33 patients underwent CT-guided radiofrequency ablation of an osteoid osteoma at our institution. To access the nidus of the clinically and radiologically suspected osteoid osteoma, a channel was drilled using the OnControl Bone Marrow Biopsy System (OBM, Arrow OnControl, Teleflex, Shavano Park, TX, USA) and a biopsy was taken. Procedure time (i.e., drilling including local anesthesia), amount of scans (i.e., single-shot fluoroscopy), radiation exposure, and the results of biopsy were investigated and compared retrospectively to a classical approach using either a manual bone biopsy system or a conventional orthopedic drill (n = 10) after ethical review board approval. Drilling the tract into the nidus was performed without problems in 22 of the 23 OBM cases. Median procedure time was 7 min compared to 13 min using the classical approach (p < 0.001). Median amount CT scans, performed to control correct positioning of the drill was comparable with 26 compared to 24.5 (p = NS) scans. Histologically, the diagnosis of osteoid osteomas could be determined in all 17 cases where a biopsy was taken. Radiofrequency ablation could be performed without problems in any case. The use of the battery-powered drill was feasible and facilitated the access to the osteoid osteoma's nidus offering the possibility to extract a specimen in the same step. (orig.)

  3. Influence of Radiofrequency Electromagnetic Fields on the Fertility System: Protocol for a Systematic Review and Meta-Analysis

    Science.gov (United States)

    Roozbeh, Nasibeh; Abdi, Fatemeh; Amraee, Azadeh; Atarodi Kashani, Zahra

    2018-01-01

    Background Due to the increased number of users of mobile phones, tablets, and other devices over the past few years, concerns about the potential impact of mobile phones on health are growing. The influence of mobile phone exposure on male fertility has been studied in recent years. Other research has shown that electromagnetic fields (EMFs) increase macrophages in the corpus luteum and growing follicles. Due to conflicting results among studies and since no systematic review has been performed to analyze the effects of radiofrequency EMF exposure from electronic devices on the fertility system in recent years, this evidence-based study is necessary. Objective The main objectives of this study are to determine the best evidence associated with the influence of radiofrequency EMFs on the fertility system and to provide insight into a potential mechanism using our observations. Methods In this systematic review, the databases and gray literature will be searched with no language and date limitation. The following databases will be searched: Cochrane Library, MEDLINE, PubMed, EMBASE, CINAHL, ProQuest, Scopus, Science Direct, Google Scholar, and other Persian databases. The combination of the Medical Subject Heading terms “radiofrequency electromagnetic” and “male reproductive system” or “female reproductive system” will be searched. Observational study designs will be included but case reports, case series, reviews, and letters to the editor will be excluded. Papers selected for retrieval will be evaluated by two independent referees for methodological validation before entering a review using the Newcastle-Ottawa Scale for nonrandomized studies and cohort studies. Results The results of this study will be submitted to a peer-reviewed journal for publication and also presented at PROSPERO. Conclusions This systematic review will provide evidence-based data on the effect of radiofrequency EMFs on the fertility system. This article will also classify the

  4. A Fractional Bipolar Radiofrequency Device Combined with a Bipolar Radiofrequency and Infrared Light Treatment for Improvement in Facial Wrinkles and Overall Skin Tone and Texture.

    Science.gov (United States)

    Gold, Alan H; Pozner, Jason; Weiss, Robert

    2016-10-01

    A variety of techniques and energy-based technologies are currently utilized for the treatment of facial wrinkles. Fractional bipolar radiofrequency treatment and treatment with bipolar radiofrequency combined with infrared light have both been reported to be safe and effective for the non-invasive treatment of wrinkles and overall facial rejuvenation. A multicenter, prospective clinical trial evaluated a protocol of treatment with a device incorporating bipolar radiofrequency and infrared light followed by treatment with a fractional bipolar radiofrequency device for facial wrinkle reduction and improvement in the overall appearance of aged facial skin. Fifty-six patients with mild to moderate facial wrinkles received three full-face treatments (forehead, nose, cheeks, periorbital, and perioral areas) at 4 to 6 week intervals and were evaluated at 12 and 24 weeks after the last treatment. Clinical photographs at baseline and follow-ups were assessed by both the investigators and patients using the Global Aesthetic Improvement scale. Treatment safety was evaluated. Study participants also completed a satisfaction and improvement questionnaire. Fitzpatrick Wrinkling and Elastosis Score was decreased significantly at three months (P radiofrequency and infrared light treatment followed by fractionated bipolar radiofrequency treatment results in safe, well tolerated, and effective improvement in overall skin tone and texture and reduction of facial wrinkles. 4 Therapeutic. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  5. Neurohumoral indicators of efficacy radiofrequency cardiac denervation

    Energy Technology Data Exchange (ETDEWEB)

    Evtushenko, A. V., E-mail: ave@cardio-tomsk.ru; Evtushenko, V. V. [National Research Tomsk State University, Tomsk (Russian Federation); Federal State Budgetary Scientific Institution “Research Institute for Cardiology”, Tomsk (Russian Federation); Saushkina, Yu. V.; Gusakova, A. M.; Suslova, T. E.; Dymbrylova, O. N.; Smyshlyaev, K. A.; Kurlov, I. O. [Federal State Budgetary Scientific Institution “Research Institute for Cardiology”, Tomsk (Russian Federation); Lishmanov, Yu. B.; Anfinogenova, Ya. D. [National Research Tomsk Polytechnic University, Tomsk (Russian Federation); Federal State Budgetary Scientific Institution “Research Institute for Cardiology”, Tomsk (Russian Federation); Sergeevichev, D. S. [Academician E.N. Meshalkin State Research Institute of Circulation Pathology, Novosibirsk (Russian Federation); Bykov, A. N.; Syryamkin, V. I.; Kistenev, Yu. V. [National Research Tomsk State University, Tomsk (Russian Federation); Lotkov, A. I. [Institute of Strength Physics and Materials Science of the Siberian Branch of the RAS, Tomsk (Russian Federation); Pokushalov, E. A.

    2015-11-17

    In this study, we compared pre- and postoperative parameters of the cardiac sympathetic innervation. The aim of the study was to examine the approaches to evaluating the quality of radiofrequency (RF)-induced cardiac denervation by using non-invasive and laboratory methods. The study included 32 people with long-lasting persistent atrial fibrillation (AF). The patients were divided into 2 groups according to the objectives of the study: group 1 (main) - 21 patients with mitral valve diseases, which simultaneously with radiofrequency ablation (RFA) AF carried out on the effects of the paraganglionic nervous plexuses by C. Pappone (2004) and N. Doll (2008) schemes. The second group (control) contained 11 patients with heart diseases in sinus rhythm (the RF denervation not been performed). All patients, who underwent surgical treatment, were received examination of cardiac sympathetic tone by using {sup 123}I-MIBG. All of them made blood analysis from ascending aorta and coronary sinus to determine the level of norepinephrine and its metabolites before and after cardiac denervation. Data of radionuclide examination are correlating with laboratory data.

  6. Effect of radiofrequency radiation from Wi-Fi devices on mercury release from amalgam restorations.

    Science.gov (United States)

    Paknahad, Maryam; Mortazavi, S M J; Shahidi, Shoaleh; Mortazavi, Ghazal; Haghani, Masoud

    2016-01-01

    Dental amalgam is composed of approximately 50% elemental mercury. Despite concerns over the toxicity of mercury, amalgam is still the most widely used restorative material. Wi-Fi is a rapidly using local area wireless computer networking technology. To the best of our knowledge, this is the first study that evaluates the effect of exposure to Wi-Fi signals on mercury release from amalgam restorations. Standard class V cavities were prepared on the buccal surfaces of 20 non-carious extracted human premolars. The teeth were randomly divided into 2 groups (n = 10). The control group was stored in non-environment. The specimens in the experimental groups were exposed to a radiofrequency radiation emitted from standard Wi Fi devices at 2.4 GHz for 20 min. The distance between the Wi-Fi router and samples was 30 cm and the router was exchanging data with a laptop computer that was placed 20 m away from the router. The concentration of mercury in the artificial saliva in the groups was evaluated by using a cold-vapor atomic absorption Mercury Analyzer System. The independent t test was used to evaluate any significant differences in mercury release between the two groups. The mean (±SD) concentration of mercury in the artificial saliva of the Wi-Fi exposed teeth samples was 0.056 ± .025 mg/L, while it was only 0.026 ± .008 mg/L in the non-exposed control samples. This difference was statistically significant (P =0.009). Exposure of patients with amalgam restorations to radiofrequency radiation emitted from conventional Wi-Fi devices can increase mercury release from amalgam restorations.

  7. Toxicological evaluation of complex industrial wastes: Implications for exposure assessment

    Energy Technology Data Exchange (ETDEWEB)

    DeMarini, D.M.; Gallagher, J.E.; Houk, V.S.; Simmons, J.E.

    1990-07-01

    We evaluated a variety of short-term bioassays to construct a battery of tests that could be used for assessing the biological effects of potentially hazardous complex industrial wastes. Ten samples were studied for hepatotoxicity; these samples and an additional five were studied for mutagenicity. Although the data are limited to these samples, the results suggest that the Salmonella assay (strain TA98) or a prophage-induction assay (both in the presence of S9) in combination with determination of relative liver weight and levels of a set of serum enzymes in rats may provide a battery of tests suitable to characterize complex industrial wastes for mutagenic and hepatotoxic potential. The biological activities exhibited by the wastes were not readily predicted by the chemical profiles of the wastes, emphasizing the importance of characterizing potentially hazardous complex industrial wastes by both chemical and biological means. DNA from liver, lung, and bladder of rats exposed to some of the wastes was analyzed by the 32P-postlabeling technique for the presence of DNA adducts. A waste that produced mutagenic urine produced a DNA adduct in bladder DNA. The implications of this approach for assessment of exposure to complex hazardous waste mixtures are discussed.

  8. Evaluation of permissible exposure to plutonium in occupational workers

    International Nuclear Information System (INIS)

    Jee, W.S.S.; Kimmel, D.B.

    1980-01-01

    No human toxicity data exist from which to evaluate the current MPBB for 239 Pu of 0.04 μCi. The current method of estimating MPBB for 239 Pu in humans uses 239 Pu: 226 Ra ratios in terms of an average skeletal dose in dogs, then compares them to the experience with 226 Ra and 228 Ra in humans. In this paper, a new approach is used that is based on data about 239 Pu toxicity in dogs and on the cellular distribution of the dose. This information has been assimilated in a computerized model of the skeleton which stimulates 239 Pu location as a function of the bone turnover rate; the model then calculates the total number of bone cell- 239 Pu disintegration interactions occurring after one intravenous injection. The number obtained is compared for beagles with a 12.5-year life span and humans with a 50-year life span. We conclude that the current human MPBB for 239 Pu from a single intravenous exposure is adequate for skeletal protection

  9. Evaluation of osprey habitat suitability and interaction with contaminant exposure

    Science.gov (United States)

    Toschik, P.C.; Christman, M.C.; Rattner, B.A.; Ottinger, M.A.

    2006-01-01

    Ospreys (Pandion haliaetus) have been the focus of conservation efforts since their dramatic population decline attributed to dichlorodiphenyltrichloroethane and related chemicals in the 1960s. Several recent studies of ospreys nesting in the United States have indicated improved reproduction. However, the density of breeding ospreys varies greatly among locations, with some areas seemingly habitable but not occupied. Because of concerns about pollution in the highly industrialized portions of the Delaware River and Bay, USA, we evaluated contaminant exposure and productivity in ospreys nesting on the Delaware River and Bay in 2002. We characterized habitat in the coastal zone of Delaware, USA, and the area around the river in Pennsylvania, USA, using data we collected as well as extant information provided by state and federal sources. We characterized habitat based on locations of occupied osprey nests in Delaware and Pennsylvania. We evaluated water clarity, water depth, land use and land cover, nest availability, and contaminants in sediment for use in a nest-occupancy model. Our results demonstrated that the presence of occupied nests was associated with water depth, water clarity, distance to an occupied osprey nest, and presence of urban land use, whereas a companion study demonstrated that hatching success was associated with the principal components derived from organochlorine-contaminant concentrations in osprey eggs (total polychlorinated biphenyls, p,p'-dichlorodiphenylethylene, chlordane and metabolites, and heptachlor epoxide). Our study provides guidelines for resource managers and local conservation organizations in management of ospreys and in development of habitat models that are appropriate for other piscivorous and marsh-nesting birds.

  10. Evaluation of automatic exposure control systems in computed tomography

    International Nuclear Information System (INIS)

    Reina, Thamiris Rosado

    2014-01-01

    The development of the computed tomography (CT) technology has brought wider possibilities on diagnostic medicine. It is a non-invasive method to see the human body in details. As the CT application increases, it raises the concern about patient dose, because the higher dose levels imparted compared to other diagnostic imaging modalities. The radiology community (radiologists, medical physicists and manufacturer) are working together to find the lowest dose level possible, without compromising the diagnostic image quality. The greatest and relatively new advance to lower the patient dose is the automatic exposure control (AEC) systems in CT. These systems are designed to ponder the dose distribution along the patient scanning and between patients taking into account their sizes and irradiated tissue densities. Based on the CT scanning geometry, the AEC-systems are very complex and their functioning is yet not fully understood. This work aims to evaluate the clinical performance of AEC-systems and their susceptibilities to assist on possible patient dose optimizations. The approach to evaluate the AEC-systems of three of the leading CT manufacturers in Brazil, General Electric, Philips and Toshiba, was the extraction of tube current modulation data from the DICOM standard image sequences, measurement and analysis of the image noise of those image sequences and measurement of the dose distribution along the scan length on the surface and inside of two different phantoms configurations. The tube current modulation of each CT scanner associated to the resulted image quality provides the performance of the AECsystem. The dose distribution measurements provide the dose profile due to the tube current modulation. Dose measurements with the AEC-system ON and OFF were made to quantify the impact of these systems regarding patient dose. The results attained give rise to optimizations on the AEC-systems applications and, by consequence, decreases the patient dose without

  11. The radio-frequency quadrupole

    CERN Document Server

    Vretenar, Maurizio

    2013-01-01

    Radio-frequency quadrupole (RFQ) linear accelerators appeared on the accelerator scene in the late 1970s and have since revolutionized the domain of low-energy proton and ion acceleration. The RFQ makes the reliable production of unprecedented ion beam intensities possible within a compact radio-frequency (RF) resonator which concentrates the three main functions of the low-energy linac section: focusing, bunching and accelerating. Its sophisticated electrode structure and strict beam dynamics and RF requirements, however, impose severe constraints on the mechanical and RF layout, making the construction of RFQs particularly challenging. This lecture will introduce the main beam optics, RF and mechanical features of a RFQ emphasizing how these three aspects are interrelated and how they contribute to the final performance of the RFQ.

  12. Evaluation of Radiation Exposure Pattern and Radiation Absorbed Dose Resulting from Occupational Exposure of Anesthesiologists to Ionizing Radiation

    Directory of Open Access Journals (Sweden)

    Maghsoudi B.

    2017-09-01

    Full Text Available Introduction: Little information is available concerning the radiation exposure of anesthesiologists, and no such data have previously been collected in Iran. This prospective study was performed to determine the amount of radiation exposure of anesthesiologists for the purpose of assessing whether or not dangerous levels of radiation exposures were being reached, and to identify factors that correlate with excessive risk. Participants and Methods: The radiation exposure of all anesthesiology residents and the attending of Shiraz University of Medical Sciences during a 3-month period (from June to August 2016 was measured using a film badge with monthly readings. Physicians were divided into two groups: group 1 (the ones assigned to ORs with radiation exposure, and group 2 (the ones assigned to ORs with no or minimal radiation exposure. Results: A total number of 10744 procedures were performed in 3 major university hospitals including 353 cases of pediatric angiography, 251 cases of percutaneous nephrolithotomy, 43 cases of chronic pain palliation and 672 cases of orthopedic surgeries with C-arm application. In all 3 months, there were statistically significant differences in the amount of radiation exposure between the two groups. Conclusion: Anesthesiologists working in the cardiac catheterization laboratory, pain treatment service, orthopedic and urologic ORs are exposed to statistically significantly higher radiation levels compared to their colleagues in other ORs. The radiation exposure to anesthesiologists can rise to high levels; therefore, they should get proper teaching, shielding and periodic evaluations.

  13. Temperature-controlled radiofrequency ablation of cardiac tissue

    DEFF Research Database (Denmark)

    Petersen, H H; Chen, X; Pietersen, Adrian

    1999-01-01

    BACKGROUND: A variety of basic factors such as electrode tip pressure, flow around the electrode and electrode orientation influence lesion size during radiofrequency ablation, but importantly is dependent on the chosen mode of ablation. However, only little information is available for the frequ......BACKGROUND: A variety of basic factors such as electrode tip pressure, flow around the electrode and electrode orientation influence lesion size during radiofrequency ablation, but importantly is dependent on the chosen mode of ablation. However, only little information is available...... for the frequently used temperature-controlled mode. The purpose of the present experimental study was to evaluate the impact during temperature-controlled radiofrequency ablation of three basic factors regarding electrode-tissue contact and convective cooling on lesion size. METHODS AND RESULTS: In vitro strips......-controlled radiofrequency ablation increased external cooling of the electrode tip due to either flow of the surrounding liquid or poor electrode tissue contact, as exemplified by perpendicular versus parallel electrode orientation, increases lesion size significantly. This is in contrast to the impact of these factors...

  14. A study of the exposure of subjects to RF radiation during MRI examinations. Measurement of the SAR of head parts and the evaluation of the measured values

    International Nuclear Information System (INIS)

    Yamada, Masayuki; Koga, Sukehiko; Sugie, Masami; Kinoshita, Kazuo; Anno, Hirofumi; Katada, Kazuhiro.

    1996-01-01

    Recently, as the fast spin echo technique has become prevailing among all the techniques in this line, there has been an increasing interest in the exposure of subjects to radiofrequency (RF) radiation during magnetic resonance imaging (MRI) examinations. On the other hand, there have been no reports about the safety of the MRI examination in Japan. For this reason, in this study, the authors aimed to evaluate the extent of the exposure of subjects to RF radiation during MRI examinations, and measured the specific absorption rate (SAR) of spherical phantoms, which assumed to be adult heads, by using the procedures set forth in two safety guidelines respectively: the 1988 Guideline of the Food and Drug Administration (FDA), and the 1995 Standards of the International Electrotechnical Commission (IEC). As a result of the measurement, it was found that the highest value of the SAR was 1.361 W/kg, which stayed far below the upper limits set forth by the respective safety guidelines referred to in the above. However, the measured values of the SAR varied depending on the respective measuring procedures. As both the measuring procedures are equivalent theoretically, the authors consider the variance to be very important. (author)

  15. Radiofrequency Ablation of Hepatic Cysts : Case Report

    International Nuclear Information System (INIS)

    Lee, Ye Ri; Kim, Pyo Nyun

    2005-01-01

    Radiofrequency ablation has been frequently performed on intra-hepatic solid tumor, namely, hepatocellular carcinoma, metastatic tumor and cholangio carcinoma, for take the cure. But, the reports of radiofrequency ablation for intrahepatic simple cysts are few. In vitro experiment of animal and in vivo treatment for intrahepatic cysts of human had been reported in rare cases. We report 4 cases of radiofrequency ablation for symptomatic intrahepatic cysts

  16. Multisource, Phase-controlled Radiofrequency for Treatment of Skin Laxity

    Science.gov (United States)

    Moreno-Moraga, Javier; Muñoz, Estefania; Cornejo Navarro, Paloma

    2011-01-01

    Objective: The objective of this study was to analyze the correlation between degrees of clinical improvement and microscopic changes detected using confocal microscopy at the temperature gradients reached in patients treated for skin laxity with a phase-controlled, multisource radiofrequency system. Design and setting: Patients with skin laxity in the abdominal area were treated in six sessions with radiofrequency (the first 4 sessions were held at 2-week intervals and the 2 remaining sessions at 3-week intervals). Patients attended monitoring at 6, 9, and 12 months. Participants: 33 patients (all women). Measurements: The authors recorded the following: variations in weight, measurements of the contour of the treated area and control area, evaluation of clinical improvement by the clinician and by the patient, images taken using an infrared camera, temperature (before, immediately after, and 20 minutes after the procedure), and confocal microscopy images (before treatment and at 6, 9, and 12 months). The degree of clinical improvement was contrasted by two external observers (clinicians). The procedure was performed using a new phase-controlled, multipolar radiofrequency system. Results: The results reveal a greater degree of clinical improvement in patients with surface temperature increases greater than 11.5ºC at the end of the procedure and remaining greater than 4.5ºC 20 minutes later. These changes induced by radiofrequency were contrasted with the structural improvements observed at the dermal-epidermal junction using confocal microscopy. Changes are more intense and are statistically correlated with patients who show a greater degree of improvement and have higher temperature gradients at the end of the procedure and 20 minutes later. Conclusion: Monitoring and the use of parameters to evaluate end-point values in skin quality treatment by multisource, phased-controlled radiofrequency can help optimize aesthetic outcome. PMID:21278896

  17. Medium-Sized Mammals around a Radioactive Liquid Waste Lagoon at Los Alamos National Laboratory: Uptake of Contaminants and Evaluation of Radio-Frequency Identification Technology

    Energy Technology Data Exchange (ETDEWEB)

    Leslie A. Hansen; Phil R. Fresquez; Rhonda J. Robinson; John D. Huchton; Teralene S. Foxx

    1999-11-01

    Use of a radioactive liquid waste lagoon by medium-sized mammals and levels of tritium, other selected radionuclides, and metals in biological tissues of the animals were documented at Technical Area 53 (TA-53) of Los Alamos National Laboratory during 1997 and 1998. Rock squirrel (Spermophilus variegates), raccoon (Procyon lotor), striped skunk (Mephitis mephitis), and bobcat (Lynx rufus) were captured at TA-53 and at a control site on the Santa Fe National Forest. Captured animals were anesthetized and marked with radio-frequency identification (RFD) tags and/or ear tags. We collected urine and hair samples for tritium and metals (aluminum, antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and thallium) analyses, respectively. In addition, muscle and bone samples from two rock squirrels collected from each of TA-53, perimeter, and regional background sites were tested for tritium, {sup 137}Cs, {sup 90}Sr, {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, and total uranium. Animals at TA-53 were monitored entering and leaving the lagoon area using a RFID monitor to read identification numbers from the RFID tags of marked animals and a separate camera system to photograph all animals passing through the monitor. Cottontail rabbit (Sylvilagus spp.), rock squirrel, and raccoon were the species most frequently photographed going through the RFID monitor. Less than half of all marked animals in the lagoon area were detected using the lagoon. Male and female rock squirrels from the lagoon area had significantly higher tritium concentrations compared to rock squirrels from the control area. Metals tested were not significantly higher in rock squirrels from TA-53, although there was a trend toward increased levels of lead in some individuals at TA-53. Muscle and bone samples from squirrels in the lagoon area appeared to have higher levels of tritium, total uranium, and {sup 137}Cs than samples collected from perimeter and

  18. Evaluation of the In Vivo Efficiency and Safety of Hepatic Radiofrequency Ablation Using a 15-G Octopus® in Pig Liver

    International Nuclear Information System (INIS)

    Lee, Eun Sun; Lee, Jeong Min; Kim, Kyung Won; Lee, In Joon; Han, Joon Koo; Choi, Byung Ihn

    2013-01-01

    To determine in vivo efficacy of radiofrequency ablation (RFA) in porcine liver by using 15-gauge Octopus® (15-G Octopus®) electrodes to create a large coagulation. A total of 18 coagulations were created by using a 180-W generator and 15-G Octopus® electrodes during laparotomy, performed in 14 pigs. Coagulation necrosis was created in the pig livers by the use of one of three RFA protocols: 1) group A, monopolar RFA using a 15-G Octopus® electrode with a 5-mm inter-electrode distance (n = 4); 2) group B, monopolar RFA using a 15-G Octopus® electrode with a 10-mm inter-electrode distance (n = 6); and 3) group C, switching monopolar RFA using two 15-G Octopus® electrodes (n = 8). The energy efficiency, shape, maximum and minimum diameters (Dmx and Dmi), and the volume of the coagulation volume were measured in each group. The Summary statistics were obtained and Mann-Whitney test was were performed. The mean ablated volume of each group was 49.23 cm 3 in A, 64.11 cm 3 in B, and 72.35 cm 3 in C. The mean Dmx and Dmi values were 5.68 cm and 4.58 cm in A and 5.97 cm and 4.97 cm in B, respectively. In group C, the mean diameters of Dmx and Dmi were 6.80 cm and 5.11 cm, respectively. The mean ratios of Dmi/Dmx were 1.25, 1.20, and 1.35 in groups A, B, and C, respectively. There was one animal death during the RFA procedure, the cause of which could not be subsequently determined. However, there were no other significant, procedure-related complications during the seven-hour-delayed CT scans. RFA procedures using 15-G Octopus® electrodes are useful and safe for creating a large ablation in a single electrode model as well as in the multiple electrodes model

  19. Evaluation of the In Vivo Efficiency and Safety of Hepatic Radiofrequency Ablation Using a 15-G Octopus® in Pig Liver

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Sun [Department of Radiology, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Lee, Jeong Min [Department of Radiology, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Kim, Kyung Won [Department of Radiology, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Lee, In Joon [National Cancer Center, Seoul 410-769 (Korea, Republic of); Han, Joon Koo; Choi, Byung Ihn [Department of Radiology, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of)

    2013-07-01

    To determine in vivo efficacy of radiofrequency ablation (RFA) in porcine liver by using 15-gauge Octopus® (15-G Octopus®) electrodes to create a large coagulation. A total of 18 coagulations were created by using a 180-W generator and 15-G Octopus® electrodes during laparotomy, performed in 14 pigs. Coagulation necrosis was created in the pig livers by the use of one of three RFA protocols: 1) group A, monopolar RFA using a 15-G Octopus® electrode with a 5-mm inter-electrode distance (n = 4); 2) group B, monopolar RFA using a 15-G Octopus® electrode with a 10-mm inter-electrode distance (n = 6); and 3) group C, switching monopolar RFA using two 15-G Octopus® electrodes (n = 8). The energy efficiency, shape, maximum and minimum diameters (Dmx and Dmi), and the volume of the coagulation volume were measured in each group. The Summary statistics were obtained and Mann-Whitney test was were performed. The mean ablated volume of each group was 49.23 cm{sup 3} in A, 64.11 cm{sup 3} in B, and 72.35 cm{sup 3} in C. The mean Dmx and Dmi values were 5.68 cm and 4.58 cm in A and 5.97 cm and 4.97 cm in B, respectively. In group C, the mean diameters of Dmx and Dmi were 6.80 cm and 5.11 cm, respectively. The mean ratios of Dmi/Dmx were 1.25, 1.20, and 1.35 in groups A, B, and C, respectively. There was one animal death during the RFA procedure, the cause of which could not be subsequently determined. However, there were no other significant, procedure-related complications during the seven-hour-delayed CT scans. RFA procedures using 15-G Octopus® electrodes are useful and safe for creating a large ablation in a single electrode model as well as in the multiple electrodes model.

  20. In vitro effects of radiofrequency electromagnetic waves on bovine spermatozoa motility.

    Science.gov (United States)

    Lukac, Norbert; Massanyi, Peter; Roychoudhury, Shubhadeep; Capcarova, Marcela; Tvrda, Eva; Knazicka, Zuzana; Kolesarova, Anna; Danko, Jan

    2011-01-01

    In this study the effects of 1800 MHz GSM-like radiofrequency electromagnetic waves (RF-EMW) exposure on bovine semen was monitored. The experimental samples were analyzed in vitro in four time periods (0, 30, 120 and 420 min) and compared with unexposed samples (control). Spermatozoa motility was determined by computer assisted semen analyzer (CASA). Evaluation of the percentage of motile spermatozoa showed significant (P radiation suggested that the parameters of path and velocity at the beginning of the culture significantly increase, but after longer culture (420 minutes) a significant decrease occur in the experimental group as compared to control. In general, results of this experiment indicate a negative time-dependent effect of 1800 MHz RF-EMW radiation on bovine spermatozoa motility.

  1. Emerging indications of endoscopic radiofrequency ablation

    Science.gov (United States)

    Becq, Aymeric; Camus, Marine; Rahmi, Gabriel; de Parades, Vincent; Marteau, Philippe

    2015-01-01

    Introduction Radiofrequency ablation (RFA) is a well-validated treatment of dysplastic Barrett's esophagus. Other indications of endoscopic RFA are under evaluation. Results Four prospective studies (total 69 patients) have shown that RFA achieved complete remission of early esophageal squamous intra-epithelial neoplasia at a rate of 80%, but with a substantial risk of stricture. In the setting of gastric antral vascular ectasia, two prospective monocenter studies, and a retrospective multicenter study, (total 51 patients), suggest that RFA is efficacious in terms of reducing transfusion dependency. In the setting of chronic hemorrhagic radiation proctopathy, a prospective monocenter study and a retrospective multicenter study (total 56 patients) suggest that RFA is an efficient treatment. A retrospective comparative study (64 patients) suggests that RFA improves stents patency in malignant biliary strictures. Conclusions Endoscopic RFA is an upcoming treatment modality in early esophageal squamous intra-epithelial neoplasia, as well as in gastric, rectal, and biliary diseases. PMID:26279839

  2. Noise exposure reconstruction and evaluation of exposure trends in two large automotive plants.

    Science.gov (United States)

    Brueck, Scott E; Prince Panaccio, Mary; Stancescu, Daniel; Woskie, Susan; Estill, Cheryl; Waters, Martha

    2013-11-01

    This study used a task-based approach to reconstruct employee noise exposures at two large automotive manufacturing plants for the period 1970-1989, utilizing historic noise measurement data, work history records, documented changes in plant operations, focus group discussions, structured interviews with long-tenure employees, and task-based job profiles. Task-based job noise exposure profiles were developed in the 1990s when the plants conducted task-based noise monitoring. Under the assumption that tasks and time-at-task profile within jobs did not change over time, these profiles were applied to historic jobs. By linking historic noise exposure measurements to job tasks, this approach allowed task-based reconstructed noise exposure profiles to capture variability of daily noise exposures. Reconstructed noise exposures, along with task-based noise exposure measurements collected at each plant during the 1990s, were analyzed to examine time trends in workplace noise levels and worker noise exposure. Our analysis of noise exposure trends revealed that noise levels for many jobs declined by ≥3 dBA from 1970 to 1998 as operational and equipment changes occurred in the plants and some noise control measures were implemented, but for some jobs, noise levels increased in the mid- to late 1990s, most likely because of an increase in production at that time. Overall, the percentage of workers exposed to noise levels >90 dBA decreased from 95% in 1970 to 54% in 1998 at one of the plants and decreased from 36% in 1970 to ~5% in 1999 at the other plant. These reductions indicate a degree of success for the hearing conservation program. However, the actual number of employees with noise exposure >90 dBA increased because of a substantial increase in the number of production employees, particularly in jobs with high noise levels, which shows a hearing conservation program challenge that companies face during periods of increased production. Future analysis of hearing levels

  3. Uranium internal exposure evaluation based on urine assay data

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, J.N.P.

    1984-09-01

    The difficulties in assessing internal exposures to uranium from urine assay data are described. A simplified application of the ICRP-30 and ICRP Lung Model concepts to the estimation of uranium intake is presented. A discussion follows on the development of a computer code utilizing the ICRP-30-based uranium elimination model with the existing urine assay information. The calculated uranium exposures from 1949 through 1983 are discussed. 13 references, 1 table.

  4. Quantitative immunochemical evaluation of fish metallothionein upon exposure to cadmium

    DEFF Research Database (Denmark)

    Yudkovski, Yana; Rogowska-Wrzesinska, Adelina; Yankelevich, Irena

    2008-01-01

    mormyrus by introducing to the assay recombinant MT and beta-actin standards. Commercial antibodies for cod MT and mammalian actin were implemented. In addition, a sensitive anti L. mormyrus MT antibody was produced, adequate only for solid phase immunochemical assays. Cadmium was applied to the fish...... clean natural sites, indicating applicability of MT as biomarker of exposure to a multi-factorial pollution, in comparison to its low revealed sensitivity to controlled cadmium exposure....

  5. The efficacy and safety of combined microneedle fractional radiofrequency and sublative fractional radiofrequency for acne scars in Asian skin.

    Science.gov (United States)

    Park, Jae Yang; Lee, Eo Gin; Yoon, Moon Soo; Lee, Hee Jung

    2016-06-01

    Microneedle fractional radiofrequency has been reported to be effective for improving wrinkles, enlarged pores and various scars. Sublative fractional radiofrequency has been shown to induce both fractional ablation of epidermis and upper dermal remodelling, which had rejuvenation effects in photoaged skin. Both modalities may have the potential synergy to improve acne scars. To evaluate the efficacy and safety of combined microneedle and sublative fractional radiofrequency for acne scars in Asian skin. Twenty subjects comprised 11 males and 9 females (mean age 23.65 ± 2.94, skin phototype III-IV) with moderate to severe acne scars. The subjects received three consecutive combined microneedle and sublative fractional radiofrequency at 4-week intervals over 12 weeks. Both blinded dermatologists and subjects assessed the clinical improvement based on the standardized photography and questionnaires, respectively. The quartile grading scale was utilized and defined as follows: grade 1, 0-25% improvement; grade 2, 26-50% improvement; grade 3, 51-75% improvement and grade 4, 76-100% improvement. All 20 subjects were assessed to have grade 2 or more clinical improvement by physicians; four (20%) had grade 4, 10 (50%) had grade 3, and six (30%) had grade 2 improvement. The subjects' grading also showed a good concordance as indicated by Kappa index of 0.695. The mean duration of post-therapy crusting was 5.2 days and post-therapy erythema lasted 2.5 days. Combined microneedle and sublative fractional radiofrequency can have a positive therapeutic effect with no serious complications and may provide a new therapeutic approach on acne scars in Asians. © 2015 Wiley Periodicals, Inc.

  6. Radiofrequency protection guidelines and standards: basic concepts and principles

    International Nuclear Information System (INIS)

    Czerski, P.

    1985-01-01

    Over the past quarter of a century, radiofrequency radiation protection guidelines and standards evolved gradually and are continuously revised and refined. The scientific rationales presented for proposed exposure limits are achieving a considerable scientific sophistication. With increasing scientific validity of the presented arguments, the values of exposure limits are converging and one may hope that they will become convincing and acceptable to all schools of thought. Still more research is needed to refine the available exposure limits. This is recognized by ANSI who revise their recommendations periodically and are now engaged in the preparation of the next revision. INIRC/IRPA is also reconsidering their interim guideline. The Australian Standards Association also stressed the temporary nature of their exposure limits

  7. Hyperkalaemia after radiofrequency ablation of hepatocellular carcinoma

    NARCIS (Netherlands)

    Verhoevena, BH; Haagsma, EB; Appeltans, BMG; Slooff, MJH; de Jong, KP

    Radiofrequency ablation of liver tumours is a useful therapy for otherwise unresectable tumours. The complication rate is said to be low. In this case report we describe hyperkalaemia after radiofrequency ablation of a hepatocellular carcinoma in a patient with end-stage renal insufficiency. (C)

  8. Radiofrequency Physics for Minimally Invasive Aesthetic Surgery.

    Science.gov (United States)

    Levy, Adam S; Grant, Robert T; Rothaus, Kenneth O

    2016-07-01

    Radiofrequency energy has a wide range of medical applications, including noninvasive treatment of wrinkles and body contouring. This technology works by differential heating of skin and soft tissue layers causing dermal remodeling or adipolysis, ultimately leading to observable effects. This article reviews the physics of radiofrequency as applied clinically. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Use of biomonitoring data to evaluate methyl eugenol exposure.

    Science.gov (United States)

    Robison, Steven H; Barr, Dana B

    2006-11-01

    Methyl eugenol is a naturally occurring material found in a variety of food sources, including spices, oils, and nutritionally important foods such as bananas and oranges. Given its natural occurrence, a broad cross-section of the population is likely exposed. The availability of biomonitoring and toxicology data offers an opportunity to examine how biomonitoring data can be integrated into risk assessment. Methyl eugenol has been used as a biomarker of exposure. An analytical method to detect methyl eugenol in human blood samples is well characterized but not readily available. Human studies indicate that methyl eugenol is short-lived in the body, and despite the high potential for exposure through the diet and environment, human blood levels are relatively low. The toxicology studies in animals demonstrate that relatively high-bolus doses administered orally result in hepatic neoplasms. However, an understanding is lacking regarding how this effect relates to the exposures that result when food containing methyl eugenol is consumed. Overall, the level of methyl eugenol detected in biomonitoring studies indicates that human exposure is several orders of magnitude lower than the lowest dose used in the bioassay. Furthermore, there are no known health effects in humans that result from typical dietary exposure to methyl eugenol.

  10. Evaluation of radiation exposure from a consumer product. A pillow

    International Nuclear Information System (INIS)

    Furuta, Etsuko; Aburai, Tamaru

    1999-01-01

    Radiation exposure from a pillow was analyzed. According to an advertisement of the pillow, this radioactive consumer product contains enough amounts of radioactive materials to induce radiation hormesis effects. The pillow consists of the filling chips made from kneading mineral ores and the polynosic linings contains natural radioactive ores. A γ-ray analysis of the pillow using pure Ge-MCA reveals that there exist radioactivities of thorium and uranium series mixtures in it at concentration of 0.58% by the weight. The observations of a chip surface by a scanning electron microscope show that the shapes of two sides are different each other. There are lots of sharp protuberances on the outside of the chip. To determine the direct external exposures from the pillow, film badges were placed on the pillow for 210 h and 2555 h. The dose equivalents of 210 h exposure was under 0.1 mSv which is a detection limit of a γ-ray by the film badges. However, that of 2555 h exposure was over 0.1 mSv less than 0.15 mSv. Quantities of internal exposures from inhalation of the vaporized Rn were measured by a Lucas Cell. It was 79 Bq/m 3 . There is no necessity for anxious about being broken in health inhaling the Rn-gass. (author)

  11. 12-month efficacy of a single radiofrequency ablation on autonomously functioning thyroid nodules.

    Science.gov (United States)

    Bernardi, Stella; Stacul, Fulvio; Michelli, Andrea; Giudici, Fabiola; Zuolo, Giulia; de Manzini, Nicolò; Dobrinja, Chiara; Zanconati, Fabrizio; Fabris, Bruno

    2017-09-01

    Radiofrequency ablation has been advocated as an alternative to radioiodine and/or surgery for the treatment of autonomously functioning benign thyroid nodules. However, only a few studies have measured radiofrequency ablation efficacy on autonomously functioning benign thyroid nodules. The aim of this work was to evaluate the 12-month efficacy of a single session of radiofrequency ablation (performed with the moving shot technique) on solitary autonomously functioning benign thyroid nodules. Thirty patients with a single, benign autonomously functioning benign thyroid nodules, who were either unwilling or ineligible to undergo surgery and radioiodine, were treated with radiofrequency ablation between April 2012 and May 2015. All the patients underwent a single radiofrequency ablation, performed with the 18-gauge needle and the moving shot technique. Clinical, laboratory, and ultrasound evaluations were scheduled at baseline, and after 1, 3, 6, and 12 months from the procedure. A single radiofrequency ablation reduced thyroid nodule volume by 51, 63, 69, and 75 % after 1, 3, 6, and 12 months, respectively. This was associated with a significant improvement of local cervical discomfort and cosmetic score. As for thyroid function, 33 % of the patients went into remission after 3 months, 43 % after 6 months, and 50 % after 12 months from the procedure. This study demonstrates that a single radiofrequency ablation allowed us to withdraw anti-thyroid medication in 50 % of the patients, who remained euthyroid afterwards. This study shows that a single radiofrequency ablation was effective in 50 % of patients with autonomously functioning benign thyroid nodules. Patients responded gradually to the treatment. It is possible that longer follow-up studies might show greater response rates.

  12. Evaluation of dabigatran exposures reported to poison control centers.

    Science.gov (United States)

    Conway, Susan E; Schaeffer, Scott E; Harrison, Donald L

    2014-03-01

    Dabigatran is a novel oral anticoagulant for which a well-defined range of toxicity and proven antidote has not been established. The primary objective of this study was to characterize dabigatran exposures reported to poison centers by dose ingested, clinical effects, treatments used, and managment sites to gain a better understanding of patient outcomes. A retrospective database review was conducted for dabigatran exposures reported to the National Poison Data System for the American Association of Poison Control Centers (AAPCC) over the period October 2010 to December 2012. There were 802 human dabigatran exposures involving adults predominantly (91% of cases). Exposure chronicity was acute in 43%, acute-on-chronic in 46%, and chronic in 11%, with the most common reason for an exposure call being an unintentional therapeutic error (70.6%). The most common management sites were on-site in 72% of cases and within a health care facility for 26%. Bleeding events and coagulopathies were the most commonly observed clinical effects. Treatments administered included activated charcoal, blood and coagulation products, hemodialysis, and supportive measures. Confirmed outcomes included death in 13 patients (1.6%), major effects in 23 (2.9%), and moderate effects in 50 (6.2%). More severe outcomes were significantly associated with adverse drug reactions, patients ≥65 years of age, those treated with blood and coagulation products and/or dialysis, and renal dysfunction (P < .05). Children experienced few moderate effects and no major effects or deaths. Severe outcomes from dabigatran exposures were not common, occurring in approximately 5% of cases.

  13. Evaluation of selected parameters on exposure rates in Westinghouse designed nuclear power plants

    International Nuclear Information System (INIS)

    Bergmann, C.A.

    1989-01-01

    During the past ten years, Westinghouse under EPRI contract and independently, has performed research and evaluation of plant data to define the trends of ex-core component exposure rates and the effects of various parameters on the exposure rates. The effects of the parameters were evaluated using comparative analyses or empirical techniques. This paper updates the information presented at the Fourth Bournemouth Conference and the conclusions obtained from the effects of selected parameters namely, coolant chemistry, physical changes, use of enriched boric acid, and cobalt input on plant exposure rates. The trends of exposure rates and relationship to doses is also presented. (author)

  14. Variations of melatonin and stress hormones under extended shifts and radiofrequency electromagnetic radiation.

    Science.gov (United States)

    Vangelova, Katia Koicheva; Israel, Mishel Salvador

    2005-01-01

    We studied the time-of-day variations in urinary levels of 6-sulphatoxy-melatonin and three stress hormones in operators working fast-rotating extended shifts under radiofrequency electromagnetic radiation (EMR). The excretion rate of the hormones was monitored by radioimmunoassay and spectrofluorimetry at 4-hour intervals in a group of 36 male operators comprising 12 broadcasting station operators, 12 TV station operators, and a control group of 12 satellite station operators. Measuring the time-weighted average (TWA) of EMR exposure revealed a high-level of exposure in broadcasting station operators (TWAmean= 3.10 microW/ cm2, TWAmax = 137.00 microW/cm2), a low-level in TV station operators (TWAmean = 1.89 microW/cm2, TWAmax = 5.24 microW/cm2), and a very low level in satellite station operators. The differences among the groups remained the same after confounding factors were taken into account. Radiofrequency EMR had no effect on the typical diurnal pattern of 6-sulphatoxymelatonin. High-level radiofrequency EMR exposure significantly increased the excretion rates of cortisol (p cortisol and noradrenaline correlated with TWAmean and TWAmax. In conclusion, the excretion of 6-sulphatoxymelatonin retained a typical diurnal pattern under fast-rotating extended shifts and radiofrequency EMR, but showed an exposure-effect relation with stress hormones.

  15. Evaluation of illnesses associated with occupational exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Frometa Suarez, I.

    1997-01-01

    A retrospective study by the Institute of Occupational Medicine is presented of all cases of pathological indications of ionizing radiation exposure during the period 1990-1995. It describes the incidence of theses diseases and their relationship with other factors. It has shown the predominance of pathologies of the haemolymphopoietic system in individuals who work in radiological diagnostics

  16. Exposure Factor considerations for safety evaluation of modern disposable diapers.

    Science.gov (United States)

    Dey, Swatee; Purdon, Mike; Kirsch, Taryn; Helbich, HansMartin; Kerr, Kenny; Li, Lijuan; Zhou, Shaoying

    2016-11-01

    Modern disposable diapers are complex products and ubiquitous globally. A robust safety assessment for disposable diapers include two important exposure parameters, i) frequency of diaper use & ii) constituent transfer from diaper to skin from direct and indirect skin contact materials. This article uses published information and original studies to quantify the exposure parameters for diapers. Using growth tables for the first three years of diapered life, an average body weight of 10-11 kg can be calculated, with a 10th percentile for females (8.5-8.8 kg). Data from surveys and diary studies were conducted to determine the frequency of use of diapers. The overall mean in the US is 4.7 diapers per day with a 75th, 90th, and 95th percentile of 5.0, 6.0, and 7.0 respectively. Using diaper topsheet-lotion transfer as a model, direct transfer to skin from the topsheet was 3.0-4.3% of the starting amount of lotion. Indirect transfer of diaper core materials as a measure of re-wetting of the skin via urine resurfacing back to the topsheet under pressure was estimated at a range of 0.32-0.66% averaging 0.46%. As described, a thorough data-based understanding of exposure is critical for a robust exposure based safety assessment of disposable diapers. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Thin slice impressions : How advertising evaluation depends on exposure duration

    NARCIS (Netherlands)

    Pieters, Rik; Elsen, M.; Wedel, M.

    The duration of exposures to advertising is often brief. Then, consumers can only obtain “thin slices” of information from the ads, such as which product and brand are being promoted. This research is the first to examine the influence that such thin slices of information have on ad and brand

  18. 47 CFR 2.801 - Radiofrequency device defined.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Radiofrequency device defined. 2.801 Section 2... MATTERS; GENERAL RULES AND REGULATIONS Marketing of Radio-frequency Devices § 2.801 Radiofrequency device defined. As used in this part, a radiofrequency device is any device which in its operation is capable of...

  19. 21 CFR 882.4725 - Radiofrequency lesion probe.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiofrequency lesion probe. 882.4725 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4725 Radiofrequency lesion probe. (a) Identification. A radiofrequency lesion probe is a device connected to a radiofrequency (RF...

  20. A re-circulated toxicity exposure chamber to evaluate hydrocarbon dispersions

    International Nuclear Information System (INIS)

    Fuller, C.B.; Bonner, J.S.; Bujnoch, J.D.; Ussery, S.F.; Arrambide, G.; Sterling, M.C.

    2002-01-01

    Traditional toxicology methods are not suitable for evaluating chemically dispersed oil which exists mostly as a colloidal suspension and as dissolved fractions. A new toxicity exposure chamber was designed with separate chambers for scaled mixing and organism exposure. The design of the chamber incorporates continuous recirculation between the mixing and exposure chamber and an upward flow in the exposure chamber. The toxicity exposure system incorporates scalable and quantitative mixing inputs with real time particle size analysis and traditional petrochemistry methods to characterize the exposure regime. Changes in dispersion were successfully translated to the organism exposure regime. The study determined the petroleum toxicity with a juvenile marine test species. Low control mortality demonstrated the usefulness of the method for testing toxicity of colloidal oil suspensions. 20 refs., 1 tab., 4 figs

  1. Non-invasive temperature monitoring using small coils during radio-frequency heating

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, Takeo; Gu, Yeun Hwa; Ushiba, Hiroaki; Hara, Kensaku; Hashimoto, Tatsuya; Nohara, Yuushi [Suzuka University, Mie (Japan); Hasegawa, Takashi [Accelerator Engineering Co, Chiba (Japan); Yamamoto, Itsuo [Yamamoto Vinyter Co, Osaka (Japan)

    1999-07-01

    In hyperthermia treatment of malignant tumors, thermal tissue injury increases drastically with every degree of increase in the tissue temperature above 42.5 .deg. C Accurate temperature monitoring during hyperthermia is important. Therefore, we developed a non-invasive method to monitor the tissue temperature during radio-frequency hyperthermia by detecting the magnetic field induced by the radio-frequency currents that flow through the heated tissue. This technique uses small multi-channel coil antennas to detect radio-frequency currents and generates two-dimensional distribution in the tissue. A rectifying circuit was connected to each coil antenna, and the current was converted with a fixed resistance into voltage. Since the voltage output from each antenna was attenuated at 1/2pr (r: distance from the radio-frequency current), single-peaked projection data were prepared, and after treatment of various signals, radio-frequency currents that flowed through the heated object were determined as a two-dimensional current distribution profile by back-projection. A high correlation was observed between the distribution of radio-frequency currents detected with the coil antennas and the temperature distribution detected by thermography. Our method of the temperature distribution suggests the possibility of non-invasive evaluation of the temperature distribution in the target of hyperthermia and clinical usefulness of this method for temperature monitoring during hyperthermia.

  2. Intraarticular Pulsed Radiofrequency to Treat Refractory Lumbar Facet Joint Pain in Patients with Low Back Pain.

    Science.gov (United States)

    Chang, Min Cheol; Cho, Yun-Woo; Ahn, Da Hyun; Do, Kyung Hee

    2018-01-06

    Many treatment techniques have been used for refractory lumbar facet joint pain; however, their efficacy has been controversial. In this study, we investigated the clinical efficacy and safety of intra-articular pulsed radiofrequency for the treatment of refractory lumbar facet joint pain in patients with low back pain. Twenty patients with refractory lumbar facet joint pain were recruited, and each patient was treated via intra-articular pulsed radiofrequency. The treatment effects were measured with a numerical rating scale, and the technical accuracy of intra-articular pulsed radiofrequency treatment was evaluated independently by 2 radiologists. Any adverse events or complications also were checked. We performed intra-articular pulsed radiofrequency treatment at 48 levels of the lumbar facet joints in 20 patients (5 men and 15 women; mean age, 64.50 ± 10.65 years) with refractory lumbar facet joint pain. Pain scores were significantly reduced at 1 month, 3 months, and 6 months after treatment (P radiofrequency results in all 20 patients, without any serious adverse effects. Treatment using intra-articular pulsed radiofrequency is an alternative to other techniques in patients with refractory lumbar facet joint pain. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. Use of Biomonitoring Data to Evaluate Methyl Eugenol Exposure

    OpenAIRE

    Robison, Steven H.; Barr, Dana B.

    2006-01-01

    Methyl eugenol is a naturally occurring material found in a variety of food sources, including spices, oils, and nutritionally important foods such as bananas and oranges. Given its natural occurrence, a broad cross-section of the population is likely exposed. The availability of biomonitoring and toxicology data offers an opportunity to examine how biomonitoring data can be integrated into risk assessment. Methyl eugenol has been used as a biomarker of exposure. An analytical method to detec...

  4. Comparative analysis of toxicological evaluations for dermal exposure performed under two different EU regulatory frameworks

    OpenAIRE

    Westerholm, Emma; Schenk, Linda

    2014-01-01

    Dermal exposure to chemicals is highly relevant in relation to the use of cosmetic products, both in consumers and in individuals exposed occupationally. Regulatory frameworks exist within the EU to limit the dermal exposure of the general population and workers to chemicals in general, as well as to limit the use of certain substances in cosmetic products. The objective of the study was to investigate and compare toxicological evaluations of dermal exposure performed under current regulatory...

  5. Evaluation of differences in ultraviolet exposure during weekend and weekday activities

    International Nuclear Information System (INIS)

    Parisi, A.V.; Mainstone, J.S.; Meldrum, L.R.; Wong, J.C.F.; Kimlin, M.G.; Aitken, J.

    2000-01-01

    The weekday UV exposures to anatomical sites were evaluated for outdoor workers, home workers, adolescents, indoor workers, school staff and students in south-east Queensland, Australia. Additionally, the UV exposures at weekends of school staff, school students, indoor workers and outdoor workers were evaluated. The weekday exposures per day ranged from 1.0 to 11.0 SED for winter to summer respectively. During spring, the ratios of the personal exposures divided by the ambient exposures at the weekend to the personal exposures divided by the ambient exposures on the weekdays to the neck, hand and left arm were at least 3.4, 2.0 and 0.67 for the indoor workers, school staff and students and outdoor workers respectively. The same ratios for the erythemal UV exposures over the year, estimated from the exposures on four days in each of the four seasons, were at least 2.3 for the school staff and at least 1.3 for the 13 to 19 year old school students. These results reinforce the importance of targeting prevention programmes to both weekend and weekday exposures. (author)

  6. Outcomes from a prospective trial of endoscopic radiofrequency ablation of early squamous cell neoplasia of the esophagus

    NARCIS (Netherlands)

    Bergman, Jacques J. G. H. M.; Zhang, Yue-Ming; He, Shun; Weusten, Bas; Xue, Liyan; Fleischer, David E.; Lu, Ning; Dawsey, Sanford M.; Wang, Gui-Qi

    2011-01-01

    Radiofrequency ablation (RFA) is safe and effective for eradicating neoplasia in Barrett's esophagus. To evaluate RFA for eradicating early esophageal squamous cell neoplasia (ESCN) defined as moderate-grade squamous intraepithelial neoplasia (MGIN) and high-grade squamous intraepithelial neoplasia

  7. Radiofrequency electromagnetic radiation from cell phone causes defective testicular function in male Wistar rats.

    Science.gov (United States)

    Oyewopo, A O; Olaniyi, S K; Oyewopo, C I; Jimoh, A T

    2017-12-01

    Cell phones have become an integral part of everyday life. As cell phone usage has become more widespread, concerns have increased regarding the harmful effects of radiofrequency electromagnetic radiation from these devices. The current study was undertaken to investigate the effects of the emitted radiation by cell phones on testicular histomorphometry and biochemical analyses. Adult male Wistar rats weighing 180-200 g were randomly allotted to control, group A (switched off mode exposure), group B (1-hr exposure), group C (2-hr exposure) and group D (3-hr exposure). The animals were exposed to radiofrequency electromagnetic radiation of cell phone for a period of 28 days. Histomorphometry, biochemical and histological investigations were carried out. The histomorphometric parameters showed no significant change (p electromagnetic radiation of cell phone leads to defective testicular function that is associated with increased oxidative stress and decreased gonadotropic hormonal profile. © 2017 Blackwell Verlag GmbH.

  8. Evaluating use stage exposure to food contact materials in a LCA framework

    DEFF Research Database (Denmark)

    Ernstoff, Alexi; Jolliet, Olivier; Fantke, Peter

    2015-01-01

    to reduce computing time and complexity, a double exponential curve was fit (R2≈1) to an exposure model which otherwise requires numeric solutions. The model is modified to evaluate the product intake fraction, PiF, which is a new metric that accounts for exposure to mass of chemicals embodied in a product...

  9. Comparative evaluation of nose-only vs. whole-body inhalation exposures for rats

    International Nuclear Information System (INIS)

    Yeh, H.C.; Snipes, M.B.; Eidson, A.F.; Hobbs, C.H.

    1988-01-01

    Two types of rat exposure chambers, nose-only and whole-body chambers, were evaluated simultaneously for the temporal and spatial distribution of the same test aerosols within the chambers, both with and without animals present. Results indicated that both types of exposure chambers performed well, with coefficients of variation less than 10% for both temporal and spatial variations. (author)

  10. Effects of radiation from a radiofrequency identification (RFID) microchip on human cancer cells.

    Science.gov (United States)

    Lai, Henry C; Chan, Ho Wing; Singh, Narendra P

    2016-01-01

    Radiofrequency identification (RFID) microchips are used to remotely identify objects, e.g. an animal in which a chip is implanted. A passive RFID microchip absorbs energy from an external source and emits a radiofrequency identification signal which is then decoded by a detector. In the present study, we investigated the effect of the radiofrequency energy emitted by a RFID microchip on human cancer cells. Molt-4 leukemia, BT474 breast cancer, and HepG2 hepatic cancer cells were exposed in vitro to RFID microchip-emitted radiofrequency field for 1 h. Cells were counted before and after exposure. Effects of pretreatment with the spin-trap compound N-tert-butyl-alpha-phenylnitrone or the iron-chelator deferoxamine were also investigated. Results We found that the energy effectively killed/retarded the growth of the three different types of cancer cells, and the effect was blocked by the spin-trap compound or the iron-chelator, whereas an inactive microchip and energy from the external source had no significant effect on the cells. Conclusions Data of the present study suggest that radiofrequency field from the microchip affects cancer cells via the Fenton Reaction. Implantation of RFID microchips in tumors may provide a new method for cancer treatment.

  11. Effects of 1.8 GHz Radiofrequency Fields on the Emotional Behavior and Spatial Memory of Adolescent Mice

    Directory of Open Access Journals (Sweden)

    Jun-Ping Zhang

    2017-11-01

    Full Text Available The increasing use of mobile phones by teenagers has raised concern about the cognitive effects of radiofrequency (RF fields. In this study, we investigated the effects of 4-week exposure to a 1.8 GHz RF field on the emotional behavior and spatial memory of adolescent male mice. Anxiety-like behavior was evaluated by open field test (OFT and elevated plus maze (EPM test, while depression-like behavior was evaluated by sucrose preference test (SPT, tail suspension test (TST and forced swim test (FST. The spatial learning and memory ability were evaluated by Morris water maze (MWM experiments. The levels of amino acid neurotransmitters were determined by liquid chromatography-mass spectrometry (LC-MS. The histology of the brain was examined by hematoxylin-eosin (HE staining. It was found that the depression-like behavior, spatial memory ability and histology of the brain did not change obviously after RF exposure. However, the anxiety-like behavior increased in mice, while, the levels of γ-aminobutyric acid (GABA and aspartic acid (Asp in cortex and hippocampus significantly decreased after RF exposure. These data suggested that RF exposure under these conditions do not affect the depression-like behavior, spatial memory and brain histology in adolescent male mice, but it may however increase the level of anxiety, and GABA and Asp were probably involved in this effect.

  12. Performance evaluation of corrosion inhibitors and galvanized steel in concrete exposure specimens.

    Science.gov (United States)

    1999-01-01

    Corrosion inhibitor admixtures (CIA) and galvanized reinforcing steel (GS) are used for the corrosion protection for reinforced concrete bridges. The results of a 3.5-year evaluation of exposure specimens containing CIA from three different manufactu...

  13. Evaluation of Image According to Exposure Conditions using Contrast-Detail Phantom for Chest Digital Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, In Ja [Dept. of Radiologic Tecnology, Dongnam Health College, Suwon (Korea, Republic of); Kim, You Hyun; Kim, Chang Nam [Dept. of Radiological Science, College of Health Science, Korea University, Seoul (Korea, Republic of); Kim, Chang Nam; Lee, Chang Yeob; Park, Kye Yeon [Dept. of Diagnostic Radiology, Korea University Guro Hospital, Seoul (Korea, Republic of)

    2009-03-15

    To find out proper photographing conditions in the chest DR imaging, the evaluation of images using the C-D phantom was carried out on relationship of identification capability, graininess, and exposure ratio. The conclusions were obtained as follows. 1. The patient's entrance skin Exposure (ESE) was decreased as tube voltage was increased. 2. According to the tube voltage change, the C-D phantom's identification capability of the exposure conditions was most visible at 110 kVp. 3. The identification capability according to the exposure ratio (mAs) change was most visible at 90 kVp for 0.5 times of low exposure ratio and at 110 kVp for 1.5 times. Therefore, it is known that the images were able to be better identified at a high exposure than a low exposure. 4. The graininess according to the exposure ratio at tube voltage of 110 kVp resulted in the best thing at 1.5 times of ratio when the exposure ratio was 1.5 times increased and the tube voltage was changed, the graininess showed the best result at 110 kVp. Therefore, the patient's exposure dose was low when kVp was increased and the adequate kVp was found to be 110. The image was better identified when exposure ratio was 1.5 times compared to 1.0 times. The graininess was also good when the exposure ratio became 1.5 times. The tube voltage was good at 110 kVp. However, once the exposure ratio is increased, the amount of radiation dose that the patients received get increased, so that the exposure condition has to be thoroughly considered.

  14. 38 CFR 1.17 - Evaluation of studies relating to health effects of radiation exposure.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Evaluation of studies relating to health effects of radiation exposure. 1.17 Section 1.17 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS Program Evaluation § 1.17 Evaluation of studies relating to health effects of radiation...

  15. Pre-Exposure Prophylaxis YouTube Videos: Content Evaluation.

    Science.gov (United States)

    Kecojevic, Aleksandar; Basch, Corey; Basch, Charles; Kernan, William

    2018-02-16

    Antiretroviral (ARV) medicines reduce the risk of transmitting the HIV virus and are recommended as daily pre-exposure prophylaxis (PrEP) in combination with safer sex practices for HIV-negative individuals at a high risk for infection, but are underused in HIV prevention. Previous literature suggests that YouTube is extensively used to share health information. While pre-exposure prophylaxis (PrEP) is a novel and promising approach to HIV prevention, there is limited understanding of YouTube videos as a source of information on PrEP. The objective of this study was to describe the sources, characteristics, and content of the most widely viewed PrEP YouTube videos published up to October 1, 2016. The keywords "pre-exposure prophylaxis" and "Truvada" were used to find 217 videos with a view count >100. Videos were coded for source, view count, length, number of comments, and selected aspects of content. Videos were also assessed for the most likely target audience. The total cumulative number of views was >2.3 million, however, a single Centers for Disease Control and Prevention video accounted for >1.2 million of the total cumulative views. A great majority (181/217, 83.4%) of the videos promoted the use of PrEP, whereas 60.8% (132/217) identified the specific target audience. In contrast, only 35.9% (78/217) of the videos mentioned how to obtain PrEP, whereas less than one third addressed the costs, side effects, and safety aspects relating to PrEP. Medical and academic institutions were the sources of the largest number of videos (66/217, 30.4%), followed by consumers (63/217, 29.0%), community-based organizations (CBO; 48/217, 22.1%), and media (40/217, 18.4%). Videos uploaded by the media sources were more likely to discuss the cost of PrEP (PYouTube videos can be used to share reliable PrEP information with individuals. Further research is needed to identify the best practices for using this medium to promote and increase PrEP uptake. ©Aleksandar Kecojevic

  16. Treatment of compensatory hyperhidrosis of the trunk with radiofrequency ablation.

    Science.gov (United States)

    Deniz, Süleyman; Kavaklı, Kuthan; Çaylak, Hasan; Purtuloğlu, Tarık; Sapmaz, Ersin; İnangil, Gökhan; Atım, Abdulkadir; Gürkök, Sedat; Kurt, Ercan

    2015-01-01

    Although Endoscopic Thoracic Sympathectomy is a widely accepted treatment method for patients with palmar hyperhidrosis, compensatory hyperhidrosis of the trunk remains a challenging side effect of the procedure. No satisfactory treatment options for this side effect were available until now. In this study, we aimed to define a new procedure for the treatment of compensatory hyperhidrosis of the trunk. A total of 10 patients admitted our institution for the treatment of compensatory hyperhidrosis of the trunk were enrolled in the study between November 2010 and January 2012 in a prospective manner. Sympathetic blockage was achieved via radiofrequency thermo-ablation technique. The results of treatment were evaluated via telephone calls. Ten patients (2 females, 8 males) underwent radiofrequency thermo-ablation of T6 sympathetic ganglion for compensatory hyperhidrosis of the trunk. The mean age was 29.2 years and the median duration of symptom was 10.5 months. The median follow-up period was 14 months. Six of ten patients (60%) were treated successfully. There was no procedure related complication. The radiofrequency treatment for patients with compensatory hyperhidrosis of the trunk is an alternative option with promising results.

  17. [Laparoscopic liver resection using a radiofrequency dissector. Initial experience].

    Science.gov (United States)

    Croce, Enrico; Olmi, Stefano; Bertolini, Aimone; Erba, Luigi; Perego, Paolo; Magnone, Stefano

    2003-01-01

    Laparoscopic liver surgery, especially when resective, requires both the skill of an expert laparoscopist and the experience of a liver surgeon. The aims of the study were to assess the feasibility of minor laparoscopic liver resection by means of a radiofrequency dissector and to evaluate the laparoscopic approach. From January 1993 to November 2002 we carried out 7 laparoscopic liver resections (3 men, 4 women), 5 of which for benign diseases and 2 for metastases from colorectal cancer. In 4 of the above resections we used an argon coagulator, while the last 3 were performed using a radiofrequency instrument. We had no perioperative or postoperative complications in this small series of patients. The mean perioperative blood loss was 120 ml (range: 80-200) and the procedure took about 90 minutes on average (range: 80-110). The mean hospital stay was 4 days and pain was adequately controlled by administering 2 ml of Toradol twice daily. We believe that the advantages of the laparoscopic technique together with the efficacy of the radiofrequency instrument in liver surgery will lead to a more widespread use of this procedure and extension of its use to include the safe execution of both minor and major resections.

  18. Cosmic rays exposure during aircraft flight (3). Guideline and dose evaluation

    International Nuclear Information System (INIS)

    Yasuda, Hiroshi

    2007-01-01

    Radiation Council of MEXT drew up the Guideline of Cosmic Ray Exposure Control for Air Crew in 2006. The content of the Guideline and evaluation methods of dose are explained. The Guideline stated five items for Airline Company. It consists of 1) exposure dose control for air crew, 2) evaluation methods of cosmic rays exposure dose of air crew, 3) explanation and education of cosmic rays exposure for air crew, 4) reading, record and store of cosmic rays exposure dose of air crew, and 5) health control of air crew. The doses of four airlines were calculated by the Civil Aeromedical Research Institute (CARI) code and the European Program package for the Calculation of Aviation Route Doses (EPCARD) code. The difference of two codes was about 15 to 25%. Japanese Internet System for Calculation of Aviation Route Doses (JISCAED) has been developed by Japan. (S.Y.)

  19. Evaluation of the risk of exposure to radon

    International Nuclear Information System (INIS)

    Monchaux, G.

    2001-01-01

    The aim of this project was to assess the risk due to inhalation of radon and its decay products using a horizontal approach across a large-scale research programme. The central objective was the assessment of human risk, a task that required a combination of several programmes and involved a multidisciplinary approach. Five main topics were addressed: radioactive aerosol studies, modelling, human studies, animal studies and retrospective assessment of radon exposure. The five studies were distributed between working groups. The rationale of this project was to pool the expertise from laboratories working in different fields of radiation protection. This paper summarises the main achievements made through this multidisciplinary research programme and the synergies that occurred between the different groups. (author)

  20. Evaluation of Noise Exposure Secondary to Wind Noise in Cyclists.

    Science.gov (United States)

    Seidman, Michael D; Wertz, Anna G; Smith, Matthew M; Jacob, Steve; Ahsan, Syed F

    2017-11-01

    Objective Determine if the noise levels of wind exposure experienced by cyclists reach levels that could contribute to noise-induced hearing loss. Study Design Industrial lab research. Setting Industrial wind tunnel. Subjects and Methods A commercial-grade electric wind tunnel was used to simulate different speeds encountered by a cyclist. A single cyclist was used during the simulation for audiometric measurements. Microphones attached near the ears of the cyclist were used to measure the sound (dB sound pressure level) experienced by the cyclist. Loudness levels were measured with the head positioned at 15-degree increments from 0 degrees to 180 degrees relative to the oncoming wind at different speeds (10-60 mph). Results Wind noise ranged from 84.9 dB at 10 mph and increased proportionally with speed to a maximum of 120.3 dB at 60 mph. The maximum of 120.3 dB was measured at the downwind ear when the ear was 90 degrees away from the wind. Conclusions Wind noise experienced by a cyclist is proportional to the speed and the directionality of the wind current. Turbulent air flow patterns are observed that contribute to increased sound exposure in the downwind ear. Consideration of ear deflection equipment without compromising sound awareness for cyclists during prolonged rides is advised to avoid potential noise trauma. Future research is warranted and can include long-term studies including dosimetry measures of the sound and yearly pre- and postexposure audiograms of cyclists to detect if any hearing loss occurs with long-term cycling.

  1. The multimedia models for the evaluation of exposure bond to the atmospheric emissions of classified installations

    International Nuclear Information System (INIS)

    Bonnard, R.

    2001-12-01

    Risk assessment and environmental impacts studies are realized to preserve the public health. Today one of the most used approach is the use of an atmospheric dispersion model to assess the risks. The data are then injected in a calculation software of exposure bond to polluted soils, to evaluate the risks of non direct exposure. This report details and evaluates the models corresponding to the need: the methodology for assessing Health Risks associated with multiple pathways of exposure to combustor, human health risk assessment proto col for hazardous waste combustion facilities, EUSES, CALTOX, MEPAS, MEND-TOX, RESRAD, MMSOILS, FRAMES-HWIR, PC-GEMS and TRIM. (A.L.B.)

  2. Effects of 900 MHz radiofrequency radiation on skin hydroxyproline contents.

    Science.gov (United States)

    Çam, Semra Tepe; Seyhan, Nesrin; Kavaklı, Cengiz; Çelikbıçak, Ömür

    2014-09-01

    The present study aimed to investigate the possible effect of pulse-modulated radiofrequency radiation (RFR) on rat skin hydroxyproline content, since skin is the first target of external electromagnetic fields. Skin hydroxyproline content was measured using liquid chromatography mass spectrometer method. Two months old male wistar rats were exposed to a 900 MHz pulse-modulated RFR at an average whole body specific absorption rate (SAR) of 1.35 W/kg for 20 min/day for 3 weeks. The radiofrequency (RF) signals were pulse modulated by rectangular pulses with a repetition frequency of 217 Hz and a duty cycle of 1:8 (pulse width 0.576 ms). A skin biopsy was taken at the upper part of the abdominal costa after the exposure. The data indicated that whole body exposure to a pulse-modulated RF radiation that is similar to that emitted by the global system for mobile communications (GSM) mobile phones caused a statistically significant increase in the skin hydroxyproline level (p = 0.049, Mann-Whitney U test). Under our experimental conditions, at a SAR less than the International Commission on Non-Ionizing Radiation Protection safety limit recommendation, there was evidence that GSM signals could alter hydroxyproline concentration in the rat skin.

  3. Evaluation of several methods for assessing the effects of occupational exposure to radiation

    International Nuclear Information System (INIS)

    Gilbert, E.S.

    1980-05-01

    The evaluation of health effects in populations occupationally exposed to low-level ionizing radiation is a matter of considerable current controversy. The analysis of data on such exposures presents a variety of problems resulting from the time dependent nature of the exposure data, certain selective biases found in working populations, and particularly limits imposed by the size of the populations, and the magnitudes of exposures received. In this paper, several methods of analysis are presented and evaluated using data from the Hanford plant for illustration. Questions of interest include whether or not to utilize an external control, and how to handle the highly skewed exposure data most effectively. Expressions for the power of various procedures are used not only to compare methods but also to evaluate the potential for detecting effects in occupationally exposed populations

  4. Difficulty Systematized Evaluation of Vocal Folds Exposure in Microsurgery of the Larynx

    Directory of Open Access Journals (Sweden)

    Ballin, Annelyse Cristine

    2010-09-01

    Full Text Available Introduction: Several studies addressing preoperative factors that predict difficulty of endotracheal intubation graduated by anesthesiologists, for the scale of the Cormack-Lehane. These parameters were evaluated for the difficulty of location of the laryngoscope in microsurgery of the larynx. There is not a standard scale of difficulty targeted to surgeons of the larynx. Objective: Create a standard scale of difficulty leasing the laryngoscope during microsurgery of the larynx, with a focus on exposure of the vocal folds (vocal cords to evaluate which clinical parameters predict difficulty of exposure of their vocal folds and verify the improvement of laryngeal exposure with the hanger of the laryngoscope. Method: A prospective randomized study, 57 patients undergoing laryngeal microsurgery. The preoperative parameters were evaluated: three epidemiological data, two of history and 13 physical examination. Intraoperatively: the anesthesiologist evaluated the Cormack-Lehane score and the surgeon evaluated according to the proposed scale, before and after placement of the hanger. Results and Conclusion: Several parameters showed sensitivity, specificity, positive predictive value for high inadequate exposure of the larynx. But only distance hiomentual <6.05 cm (p = 0.003 and 2 classes of Cormack-Lehane (p = 0.04 with statistical significance and high sensitivity of 100% and 81% respectively. The use of the hanger of laryngoscope laryngeal exposure improved significantly (p = 0.04. The proposed scale standardizes the visualization and grades the difficulty of exposure of their vocal folds, facilitating comparisons between studies and communication between otolaryngologists.

  5. Evaluation of nonuniform field exposures with coupling factors.

    Science.gov (United States)

    Sunohara, Tetsu; Hirata, Akimasa; Laakso, Ilkka; De Santis, Valerio; Onishi, Teruo

    2015-10-21

    In this study, the safety compliance for nonuniform field exposures is discussed using coupling factor concepts. The coupling factor, which is defined in the International Electrotechnical Commission 62311 standard, is extended to consider the effects of harmonics and also to apply to the specific absorption rate (for frequencies up to 30 MHz). The proposed compliance procedure is applied to and demonstrated for a prototype wireless power transfer (WPT) system with induction coupling operating at the fundamental frequency in 140 kHz band. First, measurements confirm that the perturbation of the external magnetic field strength and S11 parameter of a one-loop antenna by a human-equivalent phantom are sufficiently small, suggesting the applicability of the magneto-quasi-static approximation to frequencies up to 30 MHz. Then, the frequency characteristics of the coupling factor are derived for the WPT system. For the prototype system that is not optimized for commercial usage, the maximum allowable transmitting power is relaxed by a factor of 23 with the proposed procedure. The contribution of the harmonics decreased the allowable transmitting power by 39%, indicating their importance for safety compliance.

  6. A field evaluation of the impact of transfer efficiency on worker exposure during spray painting.

    Science.gov (United States)

    Tan, Yu-Mei; Flynn, Michael R; Buller, Thomas S

    2002-01-01

    This paper presents a mathematical model to predict breathing-zone overspray concentrations produced during spray painting as a function of the overspray generation rate, ventilation and work practices. The overspray generation rate required an estimate of the spray gun transfer efficiency, which was provided by a previously developed mathematical model. These models were evaluated in the field under two different scenarios: first in a controlled environment that approximated the assumptions of models, and then under actual spray painting conditions. Results from the first test showed the model overestimated transfer efficiency, but the measured exposures and predicted exposures were not significantly different. During actual spray painting operations, all task exposures were within a factor of three of the model predictions, and there was no statistical difference between the measured and predicted values. The predicted average exposure of each worker was within the 95% confidence interval. The overall mean exposure was within one standard error of the model prediction. The current study expands on the original exposure model by including a transfer efficiency model to provide a better estimate of the overspray generation rate. The theoretical foundation between exposure and its primary determinants is established, and this knowledge can be applied to design and can evaluate optimal control interventions. Also, the general methodology presented here for developing an exposure model is applicable to operations other than spray painting.

  7. Small Field-of-view single-shot EPI-DWI of the prostate: Evaluation of spatially-tailored two-dimensional radiofrequency excitation pulses.

    Science.gov (United States)

    Attenberger, Ulrike I; Rathmann, Nils; Sertdemir, Metin; Riffel, Philipp; Weidner, Anja; Kannengiesser, Stefan; Morelli, John N; Schoenberg, Stefan O; Hausmann, Daniel

    2016-06-01

    Spatially-tailored (RF) excitation pulses in echo-planar imaging (EPI), combined with a decreased FOV in the phase-encoding direction, enable a reduction of k-space acquisition lines, which shortens the echo train length (ETL) and reduces susceptibility artifacts. The purpose of this study was to evaluate the image quality of a zoomed EPI (z-EPI) sequence in diffusion-weighted imaging (DWI) of the prostate in comparison to a conventional single-shot EPI using single-channel (c-EPI1) and multi-channel (c-EPI2) RF excitation, with and without use of an endorectal coil. 33 consecutive patients (mean age: 61 +/- 9 years; mean PSA: 8.67±6.23 ng/ml) with examinations between 10/2012 and 02/2014 were analyzed in this retrospective study. In 26 of 33 patients the initial multiparametric (mp)-MRI was performed on a whole-body 3T scanner (Magnetom Trio, Siemens, Erlangen, Germany) using an endorectal coil (c (conventional)-EPI1). Zoomed-EPI (Z-EPI) examinations of these patients and a complete mp-MRI protocol including c-EPI2 of 7 additional patients were carried out on another 3T wb MR scanner with two-channel dynamic parallel transmit capability (Magnetom Skyra with TimTX TrueShape, Siemens). For z-EPI, the one-dimensional spatially selective RF excitation pulse was replaced by a two-dimensional RF pulse. Degree of image blur and susceptibility artifacts (0=not present to 3= non-diagnostic), maximum image distortion (mm), apparent diffusion coefficient (ADC) values, as well as overall scan preference were evaluated. SNR maps were generated to compare c-EPI2 and z-EPI. Overall image quality of z-EPI was preferred by both readers in all examinations with a single exception. Susceptibility artifacts were rated significantly lower on z-EPI compared to both other methods (z-EPI vs c-EPI1: p<0.01; z-EPI vs c-EPI2: p<0.01) as well as image blur (z-EPI vs c-EPI1: p<0.01; z-EPI vs c-EPI2: p<0.01). Image distortion was not statistically significantly reduced with z-EPI (z-EPI vs c

  8. [Sphenopalatine ganglion pulsed radiofrequency treatment in patients suffering from chronic face and head pain].

    Science.gov (United States)

    Akbas, Mert; Gunduz, Emel; Sanli, Suat; Yegin, Arif

    2016-01-01

    There are various facial pain syndromes including trigeminal neuralgia, trigeminal neuropathic pain and atypical facial pain syndromes. Effectiveness of the pulsed radiofrequency in managing various pain syndromes has been clearly demonstrated. There are a limited number of studies on the pulsed radiofrequency treatment for sphenopalatine ganglion in patients suffering from face and head pain. The purpose of this study is to evaluate the satisfaction of pulsed radiofrequency treatment at our patients retrospectively. Infrazygomatic approach was used for the pulsed radiofrequency of the sphenopalatine ganglion under fluoroscopic guidance. After the tip of the needle reached the target point, 0.25-0.5ms pulse width was applied for sensory stimulation at frequencies from 50Hz to 1V. Paraesthesias were exposed at the roof of the nose at 0.5-0.7V. To rule out trigeminal contact that led to rhythmic mandibular contraction, motor stimulation at a frequency of 2Hz was applied. Then, four cycles of pulsed radiofrequency lesioning were performed for 120s at a temperature of 42°C. Pain relief could not be achieved in 23% of the patients (unacceptable), whereas pain was completely relieved in 35% of the patients (excellent) and mild to moderate pain relief could be achieved in 42% of the patients (good) through sphenopalatine ganglion-pulsed radiofrequency treatment. Pulsed radiofrequency of the sphenopalatine ganglion is effective in treating the patients suffering from intractable chronic facial and head pain as shown by our findings. There is a need for prospective, randomized, controlled trials in order to confirm the efficacy and safety of this new treatment modality in chronic head and face pain. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  9. Sphenopalatine ganglion pulsed radiofrequency treatment in patients suffering from chronic face and head pain.

    Science.gov (United States)

    Akbas, Mert; Gunduz, Emel; Sanli, Suat; Yegin, Arif

    2016-01-01

    There are various facial pain syndromes including trigeminal neuralgia, trigeminal neuropathic pain and atypical facial pain syndromes. Effectiveness of the pulsed radiofrequency in managing various pain syndromes has been clearly demonstrated. There are a limited number of studies on the pulsed radiofrequency treatment for sphenopalatine ganglion in patients suffering from face and head pain. The purpose of this study is to evaluate the satisfaction of pulsed radiofrequency treatment at our patients retrospectively. Infrazygomatic approach was used for the pulsed radiofrequency of the sphenopalatine ganglion under fluoroscopic guidance. After the tip of the needle reached the target point, 0.25-0.5 ms pulse width was applied for sensory stimulation at frequencies from 50 Hz to 1 V. Paraesthesias were exposed at the roof of the nose at 0.5-0.7 V. To rule out trigeminal contact that led to rhythmic mandibular contraction, motor stimulation at a frequency of 2 Hz was applied. Then, four cycles of pulsed radiofrequency lesioning were performed for 120 s at a temperature of 42°C. Pain relief could not be achieved in 23% of the patients (unacceptable), whereas pain was completely relieved in 35% of the patients (excellent) and mild to moderate pain relief could be achieved in 42% of the patients (good) through sphenopalatine ganglion-pulsed radiofrequency treatment. Pulsed radiofrequency of the sphenopalatine ganglion is effective in treating the patients suffering from intractable chronic facial and head pain as shown by our findings. There is a need for prospective, randomized, controlled trials in order to confirm the efficacy and safety of this new treatment modality in chronic head and face pain. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  10. Design and evaluation of a hybrid radiofrequency applicator for magnetic resonance imaging and RF induced hyperthermia: electromagnetic field simulations up to 14.0 Tesla and proof-of-concept at 7.0 Tesla.

    Directory of Open Access Journals (Sweden)

    Lukas Winter

    Full Text Available This work demonstrates the feasibility of a hybrid radiofrequency (RF applicator that supports magnetic resonance (MR imaging and MR controlled targeted RF heating at ultrahigh magnetic fields (B0≥7.0T. For this purpose a virtual and an experimental configuration of an 8-channel transmit/receive (TX/RX hybrid RF applicator was designed. For TX/RX bow tie antenna electric dipoles were employed. Electromagnetic field simulations (EMF were performed to study RF heating versus RF wavelength (frequency range: 64 MHz (1.5T to 600 MHz (14.0T. The experimental version of the applicator was implemented at B0 = 7.0T. The applicators feasibility for targeted RF heating was evaluated in EMF simulations and in phantom studies. Temperature co-simulations were conducted in phantoms and in a human voxel model. Our results demonstrate that higher frequencies afford a reduction in the size of specific absorption rate (SAR hotspots. At 7T (298 MHz the hybrid applicator yielded a 50% iso-contour SAR (iso-SAR-50% hotspot with a diameter of 43 mm. At 600 MHz an iso-SAR-50% hotspot of 26 mm in diameter was observed. RF power deposition per RF input power was found to increase with B0 which makes targeted RF heating more efficient at higher frequencies. The applicator was capable of generating deep-seated temperature hotspots in phantoms. The feasibility of 2D steering of a SAR/temperature hotspot to a target location was demonstrated by the induction of a focal temperature increase (ΔT = 8.1 K in an off-center region of the phantom. Temperature simulations in the human brain performed at 298 MHz showed a maximum temperature increase to 48.6C for a deep-seated hotspot in the brain with a size of (19×23×32mm(3 iso-temperature-90%. The hybrid applicator provided imaging capabilities that facilitate high spatial resolution brain MRI. To conclude, this study outlines the technical underpinnings and demonstrates the basic feasibility of an 8-channel hybrid TX

  11. Ecological risk of anthropogenic pollutants to reptiles: Evaluating assumptions of sensitivity and exposure.

    Science.gov (United States)

    Weir, Scott M; Suski, Jamie G; Salice, Christopher J

    2010-12-01

    A large data gap for reptile ecotoxicology still persists; therefore, ecological risk assessments of reptiles usually incorporate the use of surrogate species. This necessitates that (1) the surrogate is at least as sensitive as the target taxon and/or (2) exposures to the surrogate are greater than that of the target taxon. We evaluated these assumptions for the use of birds as surrogates for reptiles. Based on a survey of the literature, birds were more sensitive than reptiles in less than 1/4 of the chemicals investigated. Dietary and dermal exposure modeling indicated that exposure to reptiles was relatively high, particularly when the dermal route was considered. We conclude that caution is warranted in the use of avian receptors as surrogates for reptiles in ecological risk assessment and emphasize the need to better understand the magnitude and mechanism of contaminant exposure in reptiles to improve exposure and risk estimation. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. Radiofrequency treatment alters cancer cell phenotype

    Science.gov (United States)

    Ware, Matthew J.; Tinger, Sophia; Colbert, Kevin L.; Corr, Stuart J.; Rees, Paul; Koshkina, Nadezhda; Curley, Steven; Summers, H. D.; Godin, Biana

    2015-07-01

    The importance of evaluating physical cues in cancer research is gradually being realized. Assessment of cancer cell physical appearance, or phenotype, may provide information on changes in cellular behavior, including migratory or communicative changes. These characteristics are intrinsically different between malignant and non-malignant cells and change in response to therapy or in the progression of the disease. Here, we report that pancreatic cancer cell phenotype was altered in response to a physical method for cancer therapy, a non-invasive radiofrequency (RF) treatment, which is currently being developed for human trials. We provide a battery of tests to explore these phenotype characteristics. Our data show that cell topography, morphology, motility, adhesion and division change as a result of the treatment. These may have consequences for tissue architecture, for diffusion of anti-cancer therapeutics and cancer cell susceptibility within the tumor. Clear phenotypical differences were observed between cancerous and normal cells in both their untreated states and in their response to RF therapy. We also report, for the first time, a transfer of microsized particles through tunneling nanotubes, which were produced by cancer cells in response to RF therapy. Additionally, we provide evidence that various sub-populations of cancer cells heterogeneously respond to RF treatment.

  13. Health and Fitness Evaluations for Long Duration Microgravity Exposure

    Science.gov (United States)

    Roden, Sean Kevin; Ewert, Patricia

    2006-01-01

    The current health maintenance program for ISS is adequate; however the future of medical care and research in space requires a change where crew time efficiency and autonomy are emphasized. NASA s medical personnel are currently refining their ability to monitor and provide remote health care in such a manner. The proposed plan would evaluate health and fitness of the on orbit crew to; perform on orbit operations, and readiness to return to a terrestrial environment. A two tiered approach will utilize exercise and medical equipment, as well as periodic medical conferences with the flight surgeon, to provide a quantitative and clinical picture of the crew s health and fitness. Any off nominal health and fitness issues that could arise will be evaluated by providing an "armamentarium" of devices both medical and exercise specific to the on orbit crew to use. The ability for the crew to provide autonomous health care, with decreasing earth support, will become increasingly more important for exploration missions. This new plan of health care and maintenance will allow us to, development such efforts while continuing to monitor and provide the best possible health, care and medical research through the microgravity environment on board ISS.

  14. Evaluation of effects of long term exposure on lethal toxicity with mammals

    International Nuclear Information System (INIS)

    Verma, Vibha; Yu, Qiming J.; Connell, Des W.

    2014-01-01

    The relationship between exposure time (LT 50 ) and lethal exposure concentration (LC 50 ) has been evaluated over relatively long exposure times using a novel parameter, Normal Life Expectancy (NLT), as a long term toxicity point. The model equation, ln(LT 50 ) = aLC 50 ν + b, where a, b and ν are constants, was evaluated by plotting lnLT 50 against LC 50 using available toxicity data based on inhalation exposure from 7 species of mammals. With each specific toxicant a single consistent relationship was observed for all mammals with ν always <1. Use of NLT as a long term toxicity point provided a valuable limiting point for long exposure times. With organic compounds, the Kow can be used to calculate the model constants a and v where these are unknown. The model can be used to characterise toxicity to specific mammals and then be extended to estimate toxicity at any exposure time with other mammals. -- Highlights: • Model introduces a new parameter, normal life expectancy, to explain changes in toxicity with time. • Model is innovatory as it can be used to calculate toxicity at any, particularly long exposure times. • Toxicity is influenced by normal life expectancy of the organism particularly longer exposure times. • The model was applicable to all the mammals (7 species) evaluated. • The model can be used to predict toxicity at different exposure times with untested mammals species. -- The RLE model provides a mathematical description of the change in toxicity over time for a particular chemical. This represents a major advance on the use of Haber's Rule in toxicology

  15. Evaluation of the approach to respirable quartz exposure control in U.S. coal mines.

    Science.gov (United States)

    Joy, Gerald J

    2012-01-01

    Occupational exposure to high levels of respirable quartz can result in respiratory and other diseases in humans. The Mine Safety and Health Adminstration (MSHA) regulates exposure to respirable quartz in coal mines indirectly through reductions in the respirable coal mine dust exposure limit based on the content of quartz in the airborne respirable dust. This reduction is implemented when the quartz content of airborne respirable dust exceeds 5% by weight. The intent of this dust standard reduction is to restrict miners' exposure to respirable quartz to a time-weighted average concentration of 100 μg/m(3). The effectiveness of this indirect approach to control quartz exposure was evaluated by analyzing respirable dust samples collected by MSHA inspectors from 1995 through 2008. The performance of the current regulatory approach was found to be lacking due to the use of a variable property-quartz content in airborne dust-to establish a standard for subsequent exposures. In one situation, 11.7% (4370/37,346) of samples that were below the applicable respirable coal mine dust exposure limit exceeded 100 μg/m(3) quartz. In a second situation, 4.4% (895/20,560) of samples with 5% or less quartz content in the airborne respirable dust exceeded 100 μg/m(3) quartz. In these two situations, the samples exceeding 100 μg/m(3) quartz were not subject to any potential compliance action. Therefore, the current respirable quartz exposure control approach does not reliably maintain miner exposure below 100 μg/m(3) quartz. A separate and specific respirable quartz exposure standard may improve control of coal miners' occupational exposure to respirable quartz.

  16. Maternal exposure to Cochlospermum regium: a toxicological evaluation

    Directory of Open Access Journals (Sweden)

    Andréa Luiza Cunha-Laura

    2013-02-01

    Full Text Available Cochlospermum regium (Schrank Pilg., Bixaceae, is a Brazilian plant widely used as a folk medicine in the southwestern of the Brazil to treat inflammation and infection diseases. However, the effects of C. regium hydroethanolic extract on pregnant rats have not been assessed. To evaluate the effects of the C. regium on pregnant rats during the organogenic period, the hydroethanolic extract was administered via gavage at a dose of 11.5 mg/kg/day to rats from 6th to 15th day of pregnancy. No clinical signs of maternal toxicity were observed. The placenta's and fetuses' weight were similar in control and treated animals. The term fetuses dis not present malformations or anomalies although the number of live fetuses and birth rate were significantly decreased. In conclusion, the C. regium hydroethanolic extract is nontoxicant to the pregnant rat although it would be likely to interfere in the progress of the embryofetal development.

  17. Toxicological evaluation of complex industrial wastes: Implications for exposure assessment

    Energy Technology Data Exchange (ETDEWEB)

    DeMarini, D.M.; Gallagher, J.E.; Houk, V.S.; Simmons, J.E.

    1989-01-01

    A variety of short-term bioassays to construct a battery of tests that could be used for assessing the biological effects of potentially hazardous complex industrial wastes were evaluated. Ten samples were studied for hepatotoxicity: These samples and an additional five were studied for mutagenicity. Although the data are limited to these samples, the results suggest that the Salmonella assay (either TA98 or TA100) or a prophage-induction assay (both in the presence of S9) in combination with determination of relative liver weight and levels of a set of serum enzymes in rats would provide a battery of tests suitable to characterize complex industrial wastes for mutagenic and hepatotoxic potential. The biological activities exhibited by the wastes were not readily predicted by the chemical profiles of the wastes, emphasizing the importance of characterizing potentially hazardous complex industrial wastes by both chemical and biological means.

  18. Radiofrequency ablation of liver metastases

    International Nuclear Information System (INIS)

    Pereira, P.L.; Clasen, S.; Schmidt, D.; Wiskirchen, J.; Tepe, G.; Claussen, C.D.; Boss, A.; Gouttefangeas, C.; Burkart, C.

    2004-01-01

    The liver is the second only to lymph nodes as the most common site of metastatic disease irrespective of the primary tumor. Up to 50% of all patients with malignant diseases will develop liver metastases with a significant morbidity and mortality. Although the surgical resection leads to an improvement of the survival time, only approximately 20% of the patients are eligible for surgical intervention. Radiofrequency (RF) ablation represents one of the most important alternatives as well as complementary methods for the therapy of liver metastases. RF ablation can lead in a selected patient group to a palliation or to an increased life expectancy. RF ablation appears either safer (vs. cryotherapy) or easier (vs. laser) or more effective (percutaneous ethanol instillation [PEI]), transarterial chemoembolisation [TACE] in comparison with other minimal invasive procedures. RF ablation can be performed percutaneously, laparoscopically or intraoperatively and may be combined with chemotherapy as well as with surgical resection. Permanent technical improvements of RF systems, a better understanding of the underlying electrophysiological principles and an interdisciplinary approach will lead to a prognosis improvement in patients with liver metastases. (orig.) [de

  19. [Radiofrequency ablation of liver metastases].

    Science.gov (United States)

    Pereira, P L; Clasen, S; Boss, A; Schmidt, D; Gouttefangeas, C; Burkart, C; Wiskirchen, J; Tepe, G; Claussen, C D

    2004-04-01

    The liver is the second only to lymph nodes as the most common site of metastatic disease irrespective of the primary tumor. Up to 50% of all patients with malignant diseases will develop liver metastases with a significant morbidity and mortality. Although the surgical resection leads to an improvement of the survival time, only approximately 20% of the patients are eligible for surgical intervention. Radiofrequency (RF) ablation represents one of the most important alternatives as well as complementary methods for the therapy of liver metastases. RF ablation can lead in a selected patient group to a palliation or to an increased life expectancy. RF ablation appears either safer (vs. cryotherapy) or easier (vs. laser) or more effective (percutaneous ethanol instillation [PEI], transarterial chemoembolisation [TACE]) in comparison with other minimal invasive procedures. RF ablation can be performed percutaneously, laparoscopically or intraoperatively and may be combined with chemotherapy as well as with surgical resection. Permanent technical improvements of RF systems, a better understanding of the underlying electrophysiological principles and an interdisciplinary approach will lead to a prognosis improvement in patients with liver metastases.

  20. Determination of the exposure to electromagnetic fields arising from radiofrequency identification technology (RFID) application. Final report; Bestimmung der Exposition gegenueber elektromagnetischen Feldern, die durch den Einsatz von Radio Frequency Identification (RFID) Technologien entstehen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, Gernot; Ueberbacher, Richard; Cecil, Stefan; Escorihuela-Navarro, Ana; Sainitzer, David; Weinfurter, Andreas [Seibersdorf Labor GmbH, Seibersdorf (Austria). Fachbereich EMV, Geschaeftsfeld EMC and Optics

    2012-08-15

    In the frame of this project the extent of personal exposure against electromagnetic fields caused by various types of RFID equipment has been analyzed based on measurements on selected devices and numerical computations considering practically relevant exposure scenarios. The obtained results were assessed according to the ICNIRP guidelines published in 1998. Moreover, numerical computations were carried out in order to estimate disturbance voltages induced at the input of cardiac pacemakers. All relevant frequency bands used by present RFID devices were considered. With respect to RFID transponders it was shown that they do not cause relevant exposure. Exposure figures caused by typical active RFID transponders can be expected several orders of magnitude below the corresponding basic restrictions according to ICNIRP 1998. For the assessment of exposure caused by RFID reader devices a differentiation of device categories and operating frequencies is necessary. Small reader devices or handheld readers with operating ranges less than approximately 10 cm, e.g., for reading from or writing to electronic passports, tickets, etc., are based on inductive coupling at operating frequencies 13,56 MHz and 120 kHz. From the obtained results it can be concluded that these devices cause exposure well below the ICNIRP 1998 basic restrictions. Similarly, also measurement and computational results for inductively coupled RF access control and identification systems (13,56 MHz) with even higher operating ranges up to approximately 80 cm indicate that exposure above the basic restrictions is not to be expected for such devices under usual conditions in practice. In contrast, the obtained results for inductively coupled LF reading devices with operating ranges up to approximately 80 cm (operating frequency 120-125 kHz) showed that induced current densities in the central nervous tissue above the basic restrictions are possible for particular devices if a person approaches the

  1. New resonant circuits for the ISOLTRAP radiofrequency quadrupole trap

    CERN Document Server

    SENECAL, Pierre

    2015-01-01

    This report describes my work during my Summer Student Program. My main project was building and testing a resonance-circuit box for a radio-frequency power supply used with the radio-frequency cooler and buncher.

  2. Percutaneous radiofrequency thermal lumbar sympathectomy and its clinical use

    NARCIS (Netherlands)

    J. Pernak (Jamina)

    1988-01-01

    textabstractPercutaneous radiofrequency thermolesion techniques are commonly used in the treatment of chronic pain in different pain syndromes. There are many reports describing techniques of percutaneous radiofrequency thermolesion for denervation of central & spinal nerves (Mullan 1963), 1965,

  3. Negative radiographic examinations: Evaluation of risks from exposure

    International Nuclear Information System (INIS)

    Frometa Suarez, I.; Jerez Vegueria, S.F.

    1997-01-01

    The individual dose of radiation per radiological diagnosis is decreasing, which is an important contribution for the number of exposed population. This is a result of a completed study presented by the Manuel Fajardo Surgery Clinic of the Municipality of Havana, which evaluated the behaviour of the negative radiological examinations and their contribution to the collective dose as well as the associated detriment. 486 cases with radiographic examinations are reported over a period of four months. The information on individual cases is classified by type of radiographic examination and whether the outcome of the examination was positive or negative, the absorbed doses per organ and irradiated tissue, dose equivalent, collective and effective doses. The probability of the occurrence of a fatal cancer and associated genetic damage due to the examinations is also considered. 41% of the examinations performed were negative, with a collective dose of 11.35 manSv and 52.9 % of the total doses contributed for all the radiological examinations of the population studied

  4. Elevated serum levels of heat shock protein 70 can be detected after radiofrequency ablation.

    Science.gov (United States)

    Haen, Sebastian P; Gouttefangeas, Cécile; Schmidt, Diethard; Boss, Andreas; Clasen, Stephan; von Herbay, Alexandra; Kosan, Bora; Aebert, Hermann; Pereira, Philippe L; Rammensee, Hans-Georg

    2011-09-01

    Due to their adjuvant effect and their ability to chaperone tumor-associated peptides, heat shock proteins constitute a potent alarm signal for the immune system and can lead to activation of anti-tumor T-cell immunity. Radiofrequency ablation has been reported to induce heat shock protein expression especially that of heat shock protein 70 in sublethally damaged tumor cells. In this study, we evaluated the release of heat shock protein 70 into the serum of cancer-bearing patients directly after radiofrequency ablation. Sera of 22 patients undergoing radiofrequency ablation for the treatment of primary and secondary malignancies of the liver, kidney, and lung, as well as control sera of 20 patients undergoing diagnostic liver biopsy were analyzed using a manufactured heat shock protein 70 ELISA. A significant increase in serum levels of heat shock protein 70 was detectable in the patient cohort 1 day after radiofrequency ablation. More than a twofold increase was observed in nine out of 22 patients, which tended to correlate with favorable clinical outcome. No patient of the control group revealed a comparable increase. Radiofrequency ablation can lead to a release of heat shock protein 70 into the serum, which is transiently detectable 1 day after treatment. Elevated heat shock protein 70 serum levels may constitute a biomarker for favorable clinical outcome.

  5. Percutaneous bipolar radiofrequency thermocoagulation for the treatment of lumbar disc herniation.

    Science.gov (United States)

    Zeng, Zhenhua; Yan, Min; Dai, Yi; Qiu, Weidong; Deng, Shuo; Gu, Xinzhu

    2016-08-01

    Lumbar disc herniation is usually managed with conservative treatment or surgery. However, conservative therapy seldom yields good results, and surgery is associated with multiple complications. This study aimed to assess bipolar radiofrequency thermocoagulation for the treatment of lumbar disc herniation. A total of 168 patients with lumbar disc herniation suitable for radiofrequency thermocoagulation were enrolled and randomized to monopolar radiofrequency thermocoagulation (control group, n=84) or bipolar radiofrequency thermocoagulation (experimental group, n=84) treatment groups. Ablation sites were targeted under CT scan guidance, and consecutive radiofrequency therapy was used. One and two probes were used for monopolar and bipolar thermocoagulation, respectively. Thermocoagulation was achieved at 50°C, 60°C, and 70°C for 60s each, 80°C for 90s, and 92°C for 100s. Symptoms and complications were evaluated using the modified Macnab criteria and Visual Analog Scale at 7, 30, and 180days postoperatively. At 180days, a significantly higher efficacy rate was obtained in the experimental group compared with control patients (91.6% versus 79.7%, Pdisc herniation treatment, and should be further explored for broad clinical application. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Percutaneous radiofrequency treatment of osteoid osteoma using cool-tip electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Martel, Jose [Departamento de Diagnostico por Imagen, Fundacion Hospital Alcorcon, Avda. de Budapest s/n, 28922 Alcorcon, Madrid (Spain)]. E-mail: jmartel@fhalcorcon.es; Bueno, Angel [Departamento de Diagnostico por Imagen, Fundacion Hospital Alcorcon, Avda. de Budapest s/n, 28922 Alcorcon, Madrid (Spain); Ortiz, Eduardo [Departamento de Cirugia ortopedica, Fundacion Hospital Alcorcon, Madrid (Spain)

    2005-12-15

    Objectives: To report our experience with percutaneous cool-tip radiofrequency ablation of osteoid osteomas and to evaluate clinical outcome. Methods and material: Forty-one patients with clinically and radiologically suspected osteoid osteoma were seen over a 48-month period (27 males and 14 females with a mean age of 18.7 years; range 5-43 years). Thirty-eight patients were treated by computed tomography (CT)-guided percutaneous radiofrequency ablation. The procedure was performed under regional or general anaesthesia. After location of the nidus, a 14G-bone biopsy needle is introduced into the nidus. Sampling is performed with a 17G-bone biopsy needle using a coaxial technique. The radiofrequency needle with a 10 mm active tip (cool-tip) is inserted through the biopsy needle and is connected to the radiofrequency generator for 6-8 min. Results: Primary success was obtained in 37 patients (97%) with a 100% secondary success rate. All patients are currently pain-free. No major complications occurred. Patients could resume unrestricted normal activity within 24 h. Conclusions: Percutaneous radiofrequency ablation of osteoid osteomas is an efficient and safe method that can be considered the procedure of choice for most cases.

  7. A survey on monopolar radiofrequency treatment.

    Science.gov (United States)

    Suh, Dong Hye; Hong, Eun Sun; Kim, Hyun Joo; Lee, Sang Jun; Kim, Hei Sung

    2017-09-01

    This questionnaire-based study was aimed to measure the level of appreciation, awareness of the special tips, and practice patterns of monopolar radiofrequency among Korean dermatologists practicing a specific monopolar radiofrequency device (Thermage® Inc., Hayward, CA). A total of 82 surveys were analyzed to show that the majority of participants (78.8%) were highly satisfied with the outcomes of monopolar radiofrequency treatment. All respondents were aware of the Eye Tip 0.25 cm 2 , and the majority knew the difference between the Face tip (blue) and the Total tip (orange). Most (86.3%) agreed to the statement that 900 shots were appropriate for facial tightening in those between the ages of 35 and 65 years. 66.2% of participants reported to have perform monopolar radiofrequency to extra-facial sites within the past year. As for the tips, the Total tip was most popular for all body sties and the Big tip was favored for the abdomen, thighs and buttock. We hope our data allow dermatologists to better utilize monopolar radiofrequency. © 2017 Wiley Periodicals, Inc.

  8. Transurethral radiofrequency collagen denaturation for the treatment of women with urinary incontinence.

    Science.gov (United States)

    Kang, Diana; Han, Julia; Neuberger, Molly M; Moy, M Louis; Wallace, Sheila A; Alonso-Coello, Pablo; Dahm, Philipp

    2015-03-18

    Transurethral radiofrequency collagen denaturation is a relatively novel, minimally invasive device-based intervention used to treat individuals with urinary incontinence (UI). No systematic review of the evidence supporting its use has been published to date. To evaluate the efficacy of transurethral radiofrequency collagen denaturation, compared with other interventions, in the treatment of women with UI.Review authors sought to compare the following.• Transurethral radiofrequency collagen denaturation versus no treatment/sham treatment.• Transurethral radiofrequency collagen denaturation versus conservative physical treatment.• Transurethral radiofrequency collagen denaturation versus mechanical devices (pessaries for UI).• Transurethral radiofrequency collagen denaturation versus drug treatment.• Transurethral radiofrequency collagen denaturation versus injectable treatment for UI.• Transurethral radiofrequency collagen denaturation versus other surgery for UI. We conducted a systematic search of the Cochrane Incontinence Group Specialised Register (searched 19 December 2014), EMBASE and EMBASE Classic (January 1947 to 2014 Week 50), Google Scholar and three trials registries in December 2014, along with reference checking. We sought to identify unpublished studies by handsearching abstracts of major gynaecology and urology meetings, and by contacting experts in the field and the device manufacturer. Randomised and quasi-randomised trials of transurethral radiofrequency collagen denaturation versus no treatment/sham treatment, conservative physical treatment, mechanical devices, drug treatment, injectable treatment for UI or other surgery for UI in women were eligible. We screened search results and selected eligible studies for inclusion. We assessed risk of bias and analysed dichotomous variables as risk ratios (RRs) with 95% confidence intervals (CIs) and continuous variables as mean differences (MDs) with 95% CIs. We rated the quality of

  9. Prenatal Inhalation Exposure to Evaporative Condensates of Gasoline with 15% Ethanol and Evaluation of Sensory Function in Adult Rat Offspring

    Science.gov (United States)

    The introduction of ethanol-blended automotive fuels has raised concerns about potential health effects from inhalation exposure to the combination of ethanol and gasoline hydrocarbon vapors. Previously, we evaluated effects of prenatal inhalation exposure to 100% ethanol (E100) ...

  10. Economic evaluation of health consequences of prenatal methylmercury exposure in France.

    Science.gov (United States)

    Pichery, Céline; Bellanger, Martine; Zmirou-Navier, Denis; Fréry, Nadine; Cordier, Sylvaine; Roue-Legall, Anne; Hartemann, Philippe; Grandjean, Philippe

    2012-08-10

    Evidence of a dose-response relationship between prenatal exposure to methylmercury (MeHg) and neurodevelopmental consequences in terms of IQ reduction, makes it possible to evaluate the economic consequences of MeHg exposures. To perform an economic evaluation of annual national benefits of reduction of the prenatal MeHg exposure in France. We used data on hair-Hg concentrations in French women of childbearing age (18-45 years) from a national sample of 126 women and from two studies conducted in coastal regions (n = 161and n = 503). A linear dose response function with a slope of 0.465 IQ point reduction per μg/g increase in hair-Hg concentration was used, along with a log transformation of the exposure scale, where a doubling of exposure was associated with a loss of 1.5 IQ points. The costs calculations utilized an updated estimate of €2008 17,363 per IQ point decrement, with three hypothetical exposure cut-off points (hair-Hg of 0.58, 1.0, and 2.5 μg/g). Because of higher exposure levels of women in coastal communities, the annual economic impacts based on these data were greater than those using the national data, i.e., € 1.62 billion (national), and € 3.02 billion and € 2.51 billion (regional), respectively, with the linear model, and € 5.46 billion (national), and € 9.13 billion and € 8.17 billion (regional), with the log model, for exposures above 0.58 μg/g. These results emphasize that efforts to reduce MeHg exposures would have high social benefits by preventing the serious and lifelong consequences of neurodevelopmental deficits in children.

  11. Outdoor work and solar radiation exposure: Evaluation method for epidemiological studies.

    Science.gov (United States)

    Modenese, Alberto; Bisegna, Fabio; Borra, Massimo; Grandi, Carlo; Gugliermetti, Franco; Militello, Andrea; Gobba, Fabriziomaria

    The health risk related to an excessive exposure to solar radiation (SR) is well known. The Sun represents the main exposure source for all the frequency bands of optical radiation, that is the part of the electromagnetic spectrum ranging between 100 nm and 1 mm, including infrared (IR), ultraviolet (UV) and visible radiation. According to recent studies, outdoor workers have a relevant exposure to SR but few studies available in scientific literature have attempted to retrace a detailed history of individual exposure. We propose a new method for the evaluation of SR cumulative exposure both during work and leisure time, integrating subjective and objective data. The former is collected by means of an interviewer administrated questionnaire. The latter is available through the Internet databases for many geographical regions and through individual exposure measurements. The data is integrated into a mathematical algorithm, in order to obtain an esteem of the individual total amount of SR the subjects have been exposed to during their lives. The questionnaire has been tested for 58 voluntary subjects. Environmental exposure data through online databases has been collected for 3 different places in Italy in 2012. Individual exposure by electronic UV dosimeter has been measured in 6 fishermen. A mathematical algorithm integrating subjective and objective data has been elaborated. The method proposed may be used in epidemiological studies to evaluate specific correlations with biological effects of SR and to weigh the role of the personal and environmental factors that may increase or reduce SR exposure. Med Pr 2016;67(5):577-587. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  12. Clinical application of radiofrequency ablation combined with bronchial artery infusion of docetaxel in treating non-small cell lung cancer

    International Nuclear Information System (INIS)

    Lu Xiong; Chen Fang; Lin Yun; Tan Taikang; Wei Wei

    2010-01-01

    Objective: To discuss the clinical application of radiofrequency ablation combined with bronchial artery infusion of docetaxel in treating non-small cell lung cancer and to summarize the experience of using this therapy in clinical practice. Methods: Radiofrequency ablation was performed in twenty-one patients with lung cancer. The diagnosis was confirmed by CT-guided percutaneous needle biopsy or bronchoscopic biopsy in all patients. One week after radiofrequency ablation treatment, bronchial artery infusion of docetaxel was conducted. The therapeutic results were observed and evaluated. Results: After the treatment, the lesion's size was markedly reduced and the clinical symptoms were dramatically improved in all patients. Conclusion: Radiofrequency ablation combined with bronchial artery infusion of docetaxel is a safe, effective and simple technique with excellent therapeutic results for the treatment of non-small cell lung cancer. It is really worth popularizing this technique in clinical practice. (authors)

  13. Mechanisms for enlarging lesion size during irrigated tip radiofrequency ablation

    DEFF Research Database (Denmark)

    Petersen, Helen Høgh; Roman-Gonzalez, Javier; Johnson, Susan B

    2004-01-01

    INTRODUCTION: Irrigated tip radiofrequency ablation of cardiac arrhythmias was developed to increase the size of the radiofrequency-induced lesion, since cooling of the electrode tip allows use of higher power settings. The purpose of this study was to determine if the increased lesion size during......(3) (P radiofrequency irrigated-tip ablation is that higher power levels can be used...

  14. Comparative study of four radiofrequency generators for the treatment of snoring.

    Science.gov (United States)

    Blumen, Marc B; Chalumeau, Frédéric; Gauthier, Anne; Bobin, Serge; Coste, André; Chabolle, Frédéric

    2008-03-01

    To compare the efficacy and safety of four radiofrequency generators (Ellman, Select Sutter, Coblator, Somnus) for the treatment of simple snoring. Multicenter, randomized, prospective single-blind study on 120 selected patients with simple snoring (apnea/hypopnea index Snoring sound intensity was measured on a visual analog scale and the partner's short-term satisfaction rate was evaluated after two treatment sessions maximum. Discomfort, pain, and medication intake were compared. Radiofrequency decreased the snoring sound intensity from 7.9 +/- 1.7 to 4.4 +/- 2.7 (P < 0.0001). The four radiofrequency generators had a statistically comparable efficacy. The Ellman generator caused less discomfort and required less anti-inflammatory drugs. Despite different technical characteristics, the four generators had a comparable efficacy with good safety. The Ellman generator induced the least discomfort.

  15. Clinical and radiographic evaluation of maxillary central incisors exposure in patients undergoing maxillary advancement

    Directory of Open Access Journals (Sweden)

    Guilherme dos Santos Trento

    2015-12-01

    Full Text Available Abstract Introduction: Patients with dentofacial deformities may undergo orthodontic or orthodontic-surgical treatment. Both modalities can affect esthetics. Objective: This study aims to evaluate clinical and radiographic changes in exposure of maxillary central incisors occurring after orthognathic surgery for maxillary advancement. Methods: A total of 17 patients who underwent orthognathic surgery for maxillary advancement between September, 2010 and July, 2011 were selected. Exposure of maxillary central incisors was evaluated clinically and by lateral cephalograms. Measurements were taken one week before and three months after surgery. Data were paired in terms of sex, age, nasolabial angle, height and thickness of the upper lip, the amount of maxillary advancement, clinical exposure and inclination of maxillary central incisor by statistical tests (CI 95%. Results: After maxillary advancement, incisor clinical exposure had increased even with relaxed lips and under forced smile. Moreover, there was a mean increase of 23.33% revealed by lateral cephalograms. There was an inverse correlation between upper lip thickness and incisors postsurgical exposure revealed by radiographic images (p = 0.002. Conclusions: Significant changes in the exposure of maxillary central incisors occur after maxillary advancement, under the influence of some factors, especially lip thickness.

  16. Ultrasound-guided radiofrequency ablation of thyroid gland: a preliminary study in dogs

    International Nuclear Information System (INIS)

    Choi, Ji Won; Yoo, Seung Min; Kwak, Seo Hyun

    2005-01-01

    The purpose of this study was to evaluate the possibility of using radiofrequency ablation as the treatment modality for the benign or malignant thyroid nodules in humans. Therefore, we examined the results of using radiofrequency ablation on the thyroid glands in dogs, in respect of the extent of the ablated tissue and the complications. Five dogs (10 lobes of the thyroid glands) were included in this study. US-guided radiofrequency ablation was undertaken with a 10 mm, uncovered 17 gauge cool-tip needle. The power and duration was 20 wattage and 1 minute in five thyroid lobes (group 1) and 20 wattage and 2 minutes in another 5 thyroid lobes (group 2). The ultrasound scans and the pre-and post-enhancement CT scans were undertaken before and immediately after the procedures, and at 24 hours, 72 hours and 1 week later. The US and CT findings of the ablated tissue and complications were evaluated. Blood sampling was done at the pre-procedure time and 1 week later for evaluating the functional status of the thyroid gland. Laryngoscopy was done at the pre-procedure and post-procedure times, and at 24 hours, 72 hours and 1 week later for the evaluation of any recurrent laryngeal nerve palsy. The echo pattern of the ablated thyroid gland at immediately after the radiofrequency ablation appeared as poorly marginated and hyperechoic. On the US obtained 24 hours after radiofrequency ablation, the echo pattern of the ablated thyroid gland was hypoechoic. The maximum diameters after RFA were 9.4 ρ 0.5 mm in group I and 11.4 ρ 0.5 mm in group II. The pre-enhanced CT scan taken at immediately after the radiofrequency ablation showed ill defined hypodense areas in the ablated thyroid gland. Differentiation between the normal and abnormal portions of the thyroid gland was difficult on the contrast enhanced CT scan. Complications induced by radiofrequency ablation were one recurrent laryngeal nerve palsy, two perforations of esophagus and five thickenings of the esophageal wall

  17. Evaluating indoor exposure modeling alternatives for LCA: A case study in the vehicle repair industry

    Energy Technology Data Exchange (ETDEWEB)

    Demou, Evangelia; Hellweg, Stefanie; Wilson, Michael P.; Hammond, S. Katharine; McKone, Thomas E.

    2009-05-01

    We evaluated three exposure models with data obtained from measurements among workers who use"aerosol" solvent products in the vehicle repair industry and with field experiments using these products to simulate the same exposure conditions. The three exposure models were the: 1) homogeneously-mixed-one-box model, 2) multi-zone model, and 3) eddy-diffusion model. Temporally differentiated real-time breathing zone volatile organic compound (VOC) concentration measurements, integrated far-field area samples, and simulated experiments were used in estimating parameters, such as emission rates, diffusivity, and near-field dimensions. We assessed differences in model input requirements and their efficacy for predictive modeling. The One-box model was not able to resemble the temporal profile of exposure concentrations, but it performed well concerning time-weighted exposure over extended time periods. However, this model required an adjustment for spatial concentration gradients. Multi-zone models and diffusion-models may solve this problem. However, we found that the reliable use of both these models requires extensive field data to appropriately define pivotal parameters such as diffusivity or near-field dimensions. We conclude that it is difficult to apply these models for predicting VOC exposures in the workplace. However, for comparative exposure scenarios in life-cycle assessment they may be useful.

  18. Comparison of treatment methods in lumbar spinal stenosis for geriatric patient: nerve block versus radiofrequency neurotomy versus spinal surgery.

    Science.gov (United States)

    Park, Chang Kyu; Kim, Sung Bum; Kim, Min Ki; Park, Bong Jin; Choi, Seok Geun; Lim, Young Jin; Kim, Tae Sung

    2014-09-01

    The incidence of spinal treatment, including nerve block, radiofrequency neurotomy, instrumented fusions, is increasing, and progressively involves patients of age 65 and older. Treatment of the geriatric patients is often a difficult challenge for the spine surgeon. General health, sociofamilial and mental condition of the patients as well as the treatment techniques and postoperative management are to be accurately evaluated and planned. We tried to compare three treatment methods of spinal stenosis for geriatric patient in single institution. The cases of treatment methods in spinal stenosis over than 65 years old were analyzed. The numbers of patients were 371 underwent nerve block, radiofrequency neurotomy, instrumented fusions from January 2009 to December 2012 (nerve block: 253, radiofrequency neurotomy: 56, instrumented fusions: 62). The authors reviewed medical records, operative findings and postoperative clinical results, retrospectively. Simple X-ray were evaluated and clinical outcome was measured by Odom's criteria at 1 month after procedures. We were observed excellent and good results in 162 (64%) patients with nerve block, 40 (71%) patient with radIofrequency neurotomy, 46 (74%) patient with spinal surgery. Poor results were 20 (8%) patients in nerve block, 2 (3%) patients in radiofrequency neurotomy, 3 (5%) patient in spinal surgery. We reviewed literatures and analyzed three treatment methods of spinal stenosis for geriatric patients. Although the long term outcome of surgical treatment was most favorable, radiofrequency neurotomy and nerve block can be considered for the secondary management of elderly lumbar spinals stenosis patients.

  19. Treatment of Acne Scars of Skin Types II to V by Sublative Fractional Bipolar Radiofrequency and Bipolar Radiofrequency Combined with Diode Laser

    Science.gov (United States)

    Garretson, Cara Beth

    2011-01-01

    Objective: This study evaluated the safety and efficacy of sublative fractional bipolar radiofrequency and bipolar radio frequency combined with diode laser for the treatment of both superficial and deep acne scars in patients with skin types II to V. Design: Prospective, single-center study. Subjects received up to five treatments with sublative fractional bipolar radiofrequency and bipolar radiofrequency combined with diode laser. Treatments were directed to at least two facial (forehead, perioral, cheeks) and/or neck areas with acne scars at four-week intervals. Treatment parameters on each subject were based on skin type and on skin responses to test spots on the target area just before treatment. Setting: Physician office. Participants: Subjects (n=20, aged 40.7±10.5 years [mean ± SD], skin types II–V) with acne scars and without acne lesions enrolled in this prospective study. Measurements: Results were evaluated just before each treatment and at four and 12 weeks after the final treatment using the Goodman Scar Scale, a quantitative method of evaluating scars that attempts to reduce grading subjectivity, as well as by patient satisfaction. Results: Acne scars improved significantly one month after three treatments and improvement persisted for at least 12 weeks after the fifth treatment. Improvement was not affected by skin type. Adverse effects were limited to transient erythema and edema. Conclusion: The combination of diode laser and bipolar radiofrequency energy device in addition to fractionated sublative radiofrequency is a safe and statistically significantly effective combined modality for the treatment of both superficial and deep acne scars in patients with skin types II to V with minimal downtime and no significant side effects. PMID:22010052

  20. Possible cause for altered spatial cognition of prepubescent rats exposed to chronic radiofrequency electromagnetic radiation.

    Science.gov (United States)

    Narayanan, Sareesh Naduvil; Kumar, Raju Suresh; Karun, Kalesh M; Nayak, Satheesha B; Bhat, P Gopalakrishna

    2015-10-01

    The effects of chronic and repeated radiofrequency electromagnetic radiation (RFEMR) exposure on spatial cognition and hippocampal architecture were investigated in prepubescent rats. Four weeks old male Wistar rats were exposed to RF-EMR (900 MHz; SAR-1.15 W/kg with peak power density of 146.60 μW/cm(2)) for 1 h/day, for 28 days. Followed by this, spatial cognition was evaluated by Morris water maze test. To evaluate the hippocampal morphology; H&E staining, cresyl violet staining, and Golgi-Cox staining were performed on hippocampal sections. CA3 pyramidal neuron morphology and surviving neuron count (in CA3 region) were studied using H&E and cresyl violet stained sections. Dendritic arborization pattern of CA3 pyramidal neuron was investigated by concentric circle method. Progressive learning abilities were found to be decreased in RF-EMR exposed rats. Memory retention test performed 24 h after the last training revealed minor spatial memory deficit in RF-EMR exposed group. However, RF-EMR exposed rats exhibited poor spatial memory retention when tested 48 h after the final trial. Hirano bodies and Granulovacuolar bodies were absent in the CA3 pyramidal neurons of different groups studied. Nevertheless, RF-EMR exposure affected the viable cell count in dorsal hippocampal CA3 region. RF-EMR exposure influenced dendritic arborization pattern of both apical and basal dendritic trees in RF-EMR exposed rats. Structural changes found in the hippocampus of RF-EMR exposed rats could be one of the possible reasons for altered cognition.

  1. Radio-frequency integrated-circuit engineering

    CERN Document Server

    Nguyen, Cam

    2015-01-01

    Radio-Frequency Integrated-Circuit Engineering addresses the theory, analysis and design of passive and active RFIC's using Si-based CMOS and Bi-CMOS technologies, and other non-silicon based technologies. The materials covered are self-contained and presented in such detail that allows readers with only undergraduate electrical engineering knowledge in EM, RF, and circuits to understand and design RFICs. Organized into sixteen chapters, blending analog and microwave engineering, Radio-Frequency Integrated-Circuit Engineering emphasizes the microwave engineering approach for RFICs. Provide

  2. Evaluation of exposure limits to toxic gases for nuclear reactor control room operators

    International Nuclear Information System (INIS)

    Mahlum, D.D.; Sasser, L.B.

    1991-07-01

    We have evaluated ammonia, chlorine, Halon (actually a generic name for several halogenated hydro-carbons), and sulfur dioxide for their possible effects during an acute two-minute exposure in order to derive recommendations for maximum exposure levels. To perform this evaluation, we conducted a search to find the most pertinent literature regarding toxicity in humans and in experimental animals. Much of the literature is at least a decade old, not an unexpected finding since acute exposures are less often performed now than they were a few years ago. In most cases, the studies did not specifically examine the effects of two-minute exposures; thus, extrapolations had to be made from studies of longer-exposure periods. Whenever possible, we gave the greatest weight to human data, with experimental animal data serving to strengthen the conclusion arrived at from consideration of the human data. Although certain individuals show hypersensitivity to materials like sulfur dioxide, we have not attempted to factor this information into the recommendations. After our evaluation of the data in the literature, we held a small workshop. Major participants in this workshop were three consultants, all of whom were Diplomates of the American Board of Toxicology, and staff from the Nuclear Regulatory Commission. Our preliminary recommendations for two-minute exposure limits and the rationale for them were discussed and consensus reached on final recommendations. These recommendations are: (1) ammonia-300 to 400-ppm; (2) chlorine-30 ppm; (3) Halon 1301-5%; Halon 1211-2%; and (4) sulfur dioxide-100 ppm. Control room operators should be able to tolerate two-minute exposures to these levels, don fresh-air masks, and continue to operate the reactor if the toxic material is eliminated, or safely shut down the reactor if the toxic gas remains. 96 refs., 9 tabs

  3. Computed tomography findings after radiofrequency ablation in locally advanced pancreatic cancer

    NARCIS (Netherlands)

    Rombouts, Steffi J. E.; Derksen, Tyche C.; Nio, Chung Y.; van Hillegersberg, Richard; van Santvoort, Hjalmar C.; Walma, Marieke S.; Molenaar, Izaak Q.; van Leeuwen, Maarten S.

    2018-01-01

    The purpose of the study was to provide a systematic evaluation of the computed tomography(CT) findings after radiofrequency ablation (RFA) in locally advanced pancreatic cancer(LAPC). Eighteen patients with intra-operative RFA-treated LAPC were included in a prospective case series. All CT-scans

  4. The radiofrequency frontier: a review of radiofrequency and combined radiofrequency pulsed-light technology in aesthetic medicine.

    Science.gov (United States)

    Sadick, Neil; Sorhaindo, Lian

    2005-05-01

    Radiofrequency (RF) and combined RF light source technologies have established themselves as safe and effective treatment modalities for several dermatologic procedures, including skin tightening, hair and leg vein removal, acne scarring, skin rejuvenation, and wrinkle reduction. This article reviews the technology, clinical applications, and recent advances of RF and combined RF light/laser source technologies in aesthetic medicine.

  5. Enhanced high-energy protocol using a fractional bipolar radiofrequency device combined with bipolar radiofrequency and infrared light for improving facial skin appearance and wrinkles.

    Science.gov (United States)

    Gold, Michael H; Biesman, Brian S; Taylor, Mark

    2017-06-01

    Fractional bipolar radiofrequency treatment and treatment with bipolar radiofrequency combined with infrared light have been shown in previous trials to safely and effectively improve the appearance of facial wrinkles. To evaluate a high-energy protocol with combined bipolar radiofrequency and infrared light energies for improvement in photoaged facial skin. Seventy-two patients presenting with mild to moderate facial wrinkles underwent a single full-face treatment (n=54) or two treatments (n=18) at 6-week intervals. Independent blinded assessment and investigator assessment were performed, using the Fitzpatrick Wrinkle and Elastosis Scale (0-9) and the Global Aesthetic Improvement scale. Patients also completed a self-assessment questionnaire concerning satisfaction with the treatment. All patients achieved some degree of improvement in their wrinkles and skin appearance, following a single treatment or two treatments with the enhanced-energy protocol. Blinded evaluation demonstrated 71% and 70% of the patients showing improvement of one unit or greater on the Fitzpatrick Scale, at the 12-week and 24-week follow-ups post-treatment, respectively. Similar results were reported by investigators. Under the Global Aesthetic Improvement Scale, investigators observed 87%, 91% and 81% of patients showing improvement at the 6-, 12-, and 24-week post-treatment end, respectively. Patients tolerated the treatments well and were satisfied with the clinical results. The enhanced-energy treatment protocol, with fractional bipolar radiofrequency treatment and treatment with bipolar radiofrequency combined with infrared light applications, yields significant improvement of skin texture, wrinkling, and overall appearance following a single treatment. The results appear gradually over time and are maintained for at least 6 months' post-treatment. © 2017 Wiley Periodicals, Inc.

  6. Evaluating chemical exposure and effect models for aquatic species with a focus on crude oil constituents

    NARCIS (Netherlands)

    Hoop, L. de

    2016-01-01

    The aim of this PhD thesis is to evaluate a suite of exposure and effect models on their applicability in ecological risk assessment for aquatic species and ecosystems. The focus is on oil constituents, as it is largely unknown whether current ecological models are applicable to crude oil and its

  7. Evaluation of total risk exposure and insurance premiums in the maritime industry

    NARCIS (Netherlands)

    S. Knapp (Sabine); C. Heij (Christiaan)

    2016-01-01

    textabstractThis study provides an empirical evaluation of maritime risk exposure expressed as the monetary value at risk (MVR), which incorporates life of crew and passengers, vessel value of hull and machinery, carried cargo value, third party liabilities, and potential external damages like

  8. Gender-specific evaluation of variation of maxillary exposure when smiling.

    Science.gov (United States)

    Pausch, Niels Christian; Katsoulis, Dimitrios

    2017-06-01

    Excessive exposure of maxillary teeth when smiling can have a negative effect on the aesthetics and attractiveness of the face. The presented study was aimed to evaluate the effect of different amounts of gingival exposure on the perception of such human characteristics and qualities as age, attractiveness, gender specificity, and felt sympathy in the context of the whole face. Forty-two participants (21 female and 21 male students of Dental Medicine) were recruited as evaluators for the study. Two average-looking subjects (one female, one male) were photographed. The images were processed to create a series of eight clones with different gingival exposure (shift A-H; A = full over-exposure, H = invisibility of the crown surfaces of the teeth). The panellists evaluated characteristics as attractiveness, gender specificity, age, and felt sympathy. 42 participants joined the study (21 female, 21 male). Shift H was assessed as worst for sympathy and attractiveness, and resulted in the highest estimated age. Best attractiveness was observed for shifts C and D. Gender dimorphism was noticed, with own gender being rated as less attractive and opposite gender as more attractive. Female and male evaluators assess excessive gingival and maxillary incisor display differently for female and male probands. Excessive over- or underexposure of the maxillary gingiva and teeth when smiling is perceived as unattractive and results in less observer sympathy. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  9. Association of Exposure to Radio-Frequency Electromagnetic Field Radiation (RF-EMFR) Generated by Mobile Phone Base Stations with Glycated Hemoglobin (HbA1c) and Risk of Type 2 Diabetes Mellitus.

    Science.gov (United States)

    Meo, Sultan Ayoub; Alsubaie, Yazeed; Almubarak, Zaid; Almutawa, Hisham; AlQasem, Yazeed; Hasanato, Rana Muhammed

    2015-11-13

    Installation of mobile phone base stations in residential areas has initiated public debate about possible adverse effects on human health. This study aimed to determine the association of exposure to radio frequency electromagnetic field radiation (RF-EMFR) generated by mobile phone base stations with glycated hemoglobin (HbA1c) and occurrence of type 2 diabetes mellitus. For this study, two different elementary schools (school-1 and school-2) were selected. We recruited 159 students in total; 96 male students from school-1, with age range 12-16 years, and 63 male students with age range 12-17 years from school-2. Mobile phone base stations with towers existed about 200 m away from the school buildings. RF-EMFR was measured inside both schools. In school-1, RF-EMFR was 9.601 nW/cm² at frequency of 925 MHz, and students had been exposed to RF-EMFR for a duration of 6 h daily, five days in a week. In school-2, RF-EMFR was 1.909 nW/cm² at frequency of 925 MHz and students had been exposed for 6 h daily, five days in a week. 5-6 mL blood was collected from all the students and HbA1c was measured by using a Dimension Xpand Plus Integrated Chemistry System, Siemens. The mean HbA1c for the students who were exposed to high RF-EMFR was significantly higher (5.44 ± 0.22) than the mean HbA1c for the students who were exposed to low RF-EMFR (5.32 ± 0.34) (p = 0.007). Moreover, students who were exposed to high RF-EMFR generated by MPBS had a significantly higher risk of type 2 diabetes mellitus (p = 0.016) relative to their counterparts who were exposed to low RF-EMFR. It is concluded that exposure to high RF-EMFR generated by MPBS is associated with elevated levels of HbA1c and risk of type 2 diabetes mellitus.

  10. Association of Exposure to Radio-Frequency Electromagnetic Field Radiation (RF-EMFR Generated by Mobile Phone Base Stations with Glycated Hemoglobin (HbA1c and Risk of Type 2 Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    Sultan Ayoub Meo

    2015-11-01

    Full Text Available Installation of mobile phone base stations in residential areas has initiated public debate about possible adverse effects on human health. This study aimed to determine the association of exposure to radio frequency electromagnetic field radiation (RF-EMFR generated by mobile phone base stations with glycated hemoglobin (HbA1c and occurrence of type 2 diabetes mellitus. For this study, two different elementary schools (school-1 and school-2 were selected. We recruited 159 students in total; 96 male students from school-1, with age range 12–16 years, and 63 male students with age range 12–17 years from school-2. Mobile phone base stations with towers existed about 200 m away from the school buildings. RF-EMFR was measured inside both schools. In school-1, RF-EMFR was 9.601 nW/cm2 at frequency of 925 MHz, and students had been exposed to RF-EMFR for a duration of 6 h daily, five days in a week. In school-2, RF-EMFR was 1.909 nW/cm2 at frequency of 925 MHz and students had been exposed for 6 h daily, five days in a week. 5–6 mL blood was collected from all the students and HbA1c was measured by using a Dimension Xpand Plus Integrated Chemistry System, Siemens. The mean HbA1c for the students who were exposed to high RF-EMFR was significantly higher (5.44 ± 0.22 than the mean HbA1c for the students who were exposed to low RF-EMFR (5.32 ± 0.34 (p = 0.007. Moreover, students who were exposed to high RF-EMFR generated by MPBS had a significantly higher risk of type 2 diabetes mellitus (p = 0.016 relative to their counterparts who were exposed to low RF-EMFR. It is concluded that exposure to high RF-EMFR generated by MPBS is associated with elevated levels of HbA1c and risk of type 2 diabetes mellitus.

  11. Curative effect and mechanism of radiofrequency ablation nucleoplasty in the treatment of cervical vertigo.

    Science.gov (United States)

    Yin, Hai-Dong; Zhang, Xin-Mei; Huang, Ming-Guang; Chen, Wei; Song, Yang; Du, Qing-Jun; Wu, Yu-Ning; Yang, Ruo-Bin

    2017-04-01

    This study aims to investigate the curative effects and mechanism of radiofrequency ablation nucleoplasty in the treatment of cervical vertigo. A total of 27 patients diagnosed with cervical vertigo from January 2012 to October 2014 received treatment of radiofrequency ablation nucleoplasty. The narrow-side vertebral artery diameters were examined by using Philips 1.5-T body dual-gradient MRI system. The haemodynamic parameters were detected by using transcranial Doppler sonography. Both of the vertebral artery diameters and haemodynamic parameters were recorded and compared before and after treatment. The curative effects in early post-operative application were evaluated according to the Nagashima standards. Radiofrequency ablation nucleoplasty was performed in a total of 59 cervical discs in 27 patients. The average operation time was 42.7 min, and the symptoms of 92.6% patients were alleviated after radiofrequency ablation nucleoplasty post-operation application. There was no significant difference in the narrow-side vertebral artery diameters before and after treatment in both Group A (p = 0.12) and Group B (p = 0.48); however, the blood flow velocity was significantly higher than that before treatment in both Group A (p = 0.01) and Group B (p = 0.03), respectively. Radiofrequency ablation nucleoplasty improves the blood flow in the narrow-side vertebral artery and illustrates the therapeutic effect on cervical vertigo in patients who have no direct compression of the vertebral artery. Advances in knowledge: Radiofrequency intradiscal nucleoplasty can be used as a minimally invasive procedure for treating cervical vertigo.

  12. Management of trigeminal neuralgia by radiofrequency ...

    African Journals Online (AJOL)

    The outcome depends on the type of TN with best results with classical idiopathic type. Also better results occurred with isolated V3 affection. The radiofrequency thermocoagulation of trigeminal nerve is a low risk, highly effective and minimally invasive procedure that should be started with in all cases of TN.

  13. Modes of oscillation in radiofrequency Paul traps

    DEFF Research Database (Denmark)

    Landa, H.; Reznik, B.; Drewsen, M.

    2012-01-01

    We examine the time-dependent dynamics of ion crystals in radiofrequency traps. The problem of stable trapping of general threedimensional crystals is considered and the validity of the pseudopotential approximation is discussed. We analytically derive the micromotion amplitude of the ions...

  14. Radiofrequency and microwave interactions between biomolecular systems

    Czech Academy of Sciences Publication Activity Database

    Kučera, Ondřej; Cifra, Michal

    2016-01-01

    Roč. 42, č. 1 (2016), s. 1-8 ISSN 0092-0606 R&D Projects: GA ČR(CZ) GA15-17102S Institutional support: RVO:67985882 Keywords : Cell signaling * Radiofrequency * Bioelectrodynamics Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.241, year: 2016

  15. Outdoor and indoor sources of residential radiofrequency electromagnetic fields, personal cell phone and cordless phone use, and cognitive function in 5-6 years old children

    NARCIS (Netherlands)

    Guxens, Mònica; Vermeulen, Roel; van Eijsden, Manon; Beekhuizen, Johan; Vrijkotte, Tanja G. M.; van Strien, Rob T.; Kromhout, Hans; Huss, Anke

    2016-01-01

    Little is known about the exposure of young children to radiofrequency electromagnetic fields (RF-EMF) and potentially associated health effects. We assessed the relationship between residential RF-EMF exposure from mobile phone base stations, residential presence of indoor sources, personal cell

  16. Outdoor and indoor sources of residential radiofrequency electromagnetic fields, personal cell phone and cordless phone use, and cognitive function in 5-6 years old children

    NARCIS (Netherlands)

    Guxens, Mònica; Vermeulen, Roel|info:eu-repo/dai/nl/216532620; van Eijsden, Manon; Beekhuizen, Johan|info:eu-repo/dai/nl/34472641X; Vrijkotte, Tanja G M; van Strien, Rob T; Kromhout, Hans|info:eu-repo/dai/nl/074385224; Huss, Anke|info:eu-repo/dai/nl/331385880

    2016-01-01

    BACKGROUND: Little is known about the exposure of young children to radiofrequency electromagnetic fields (RF-EMF) and potentially associated health effects. We assessed the relationship between residential RF-EMF exposure from mobile phone base stations, residential presence of indoor sources,

  17. EVALUATION AND COMPARISON OF URINARY METABOLIC BIOMARKERS OF EXPOSURE FOR THE JET FUEL JP-8

    OpenAIRE

    B’Hymer, Clayton; Krieg, Edward; Cheever, Kenneth L.; Toennis, Christine A.; Clark, John C.; Kesner, James S.; Gibson, Roger; Butler, Mary Ann

    2012-01-01

    A study of workers exposed to jet fuel propellant 8 (JP-8) was conducted at U.S. Air Force bases and included the evaluation of three biomarkers of exposure: S-benzylmercapturic acid (BMA), S-phenylmercapturic acid (PMA), and (2-methoxyethoxy)acetic acid (MEAA). Postshift urine specimens were collected from various personnel categorized as high (n = 98), moderate (n = 38) and low (n = 61) JP-8 exposure based on work activities. BMA and PMA urinary levels were determined by high-performance li...

  18. Research strategies for safety evaluation of nanomaterials, Part I: evaluating the human health implications of exposure to nanoscale materials.

    Science.gov (United States)

    Thomas, Karluss; Sayre, Philip

    2005-10-01

    Nanotechnology has the potential to dramatically improve the effectiveness of a number of existing consumer and industrial products and could have a substantial impact on the development of new products ranging from disease diagnosis and treatment to environmental remediation. The broad range of possible nanotechnology applications could lead to substantive changes in industrial productivity, economic growth, and international trade. A continuing evaluation of the human health implications of exposure to nanoscale materials will be essential before the commercial benefits of these materials can be fully realized. The purpose of this article is to review the human health implications of exposure to nanoscale materials in the context of a toxicological risk evaluation, the current scope of U.S. Federal research on nanoscale materials, and selected toxicological studies associated with nanoscale materials to note emerging research in this area.

  19. QUALITY OF RADIOGRAPHIC IMAGES: LABORATORY EVALUATION OF INTRAORAL FILMS, FILTERS, COLLIMATORS, AND RADIATION EXPOSURE

    Directory of Open Access Journals (Sweden)

    TAMBURUS José Roberto

    1997-01-01

    Full Text Available In order to evaluate density, radiographic contrast and dose of radiation exposure, the author analyzed 80 radiographs containing 640 optical density data of the images of a penetrometer, exposed to the radiation beam with combinations between D and E periapical films, aluminum and copper/aluminum filters, and circular or rectangular collimators. The data obtained were analyzed by ANOVA and allowed the following conclusions: 1 aluminum filtration resulted in improved image contrast; 2 the use of group D film and an aluminum filter produced improved image contrast quality; 3 the rectangular collimator contributed to the production of improved contrast and to the reduction of radiation exposure, but did not affect density; 4 the combination of copper/aluminum filter, E group film and rectangular collimation significantly reduced radiation exposure.

  20. Consumer exposure to biocides - identification of relevant sources and evaluation of possible health effects

    Directory of Open Access Journals (Sweden)

    Heger Wolfgang

    2010-02-01

    Full Text Available Abstract Background Products containing biocides are used for a variety of purposes in the home environment. To assess potential health risks, data on products containing biocides were gathered by means of a market survey, exposures were estimated using a worst case scenario approach (screening, the hazard of the active components were evaluated, and a preliminary risk assessment was conducted. Methods Information on biocide-containing products was collected by on-site research, by an internet inquiry as well as research into databases and lists of active substances. Twenty active substances were selected for detailed investigation. The products containing these substances were subsequently classified by range of application; typical concentrations were derived. Potential exposures were then estimated using a worst case scenario approach according to the European Commission's Technical Guidance Document on Risk Assessment. Relevant combinations of scenarios and active substances were identified. The toxicological data for these substances were compiled in substance dossiers. For estimating risks, the margins of exposure (MOEs were determined. Results Numerous consumer products were found to contain biocides. However, it appeared that only a limited number of biocidal active substances or groups of biocidal active substances were being used. The lowest MOEs for dermal exposure or exposure by inhalation were obtained for the following scenarios and biocides: indoor pest control using sprays, stickers or evaporators (chlorpyrifos, dichlorvos and spraying of disinfectants as well as cleaning of surfaces with concentrates (hydrogen peroxide, formaldehyde, glutardialdehyde. The risk from aggregate exposure to individual biocides via different exposure scenarios was higher than the highest single exposure on average by a factor of three. From the 20 biocides assessed 10 had skin-sensitizing properties. The biocides isothiazolinone (mixture of 5-chloro

  1. Spatial resolution requirements for traffic-related air pollutant exposure evaluations

    Science.gov (United States)

    Batterman, Stuart; Chambliss, Sarah; Isakov, Vlad

    2014-09-01

    Vehicle emissions represent one of the most important air pollution sources in most urban areas, and elevated concentrations of pollutants found near major roads have been associated with many adverse health impacts. To understand these impacts, exposure estimates should reflect the spatial and temporal patterns observed for traffic-related air pollutants. This paper evaluates the spatial resolution and zonal systems required to estimate accurately intraurban and near-road exposures of traffic-related air pollutants. The analyses use the detailed information assembled for a large (800 km2) area centered on Detroit, Michigan, USA. Concentrations of nitrogen oxides (NOx) due to vehicle emissions were estimated using hourly traffic volumes and speeds on 9700 links representing all but minor roads in the city, the MOVES2010 emission model, the RLINE dispersion model, local meteorological data, a temporal resolution of 1 h, and spatial resolution as low as 10 m. Model estimates were joined with the corresponding shape files to estimate residential exposures for 700,000 individuals at property parcel, census block, census tract, and ZIP code levels. We evaluate joining methods, the spatial resolution needed to meet specific error criteria, and the extent of exposure misclassification. To portray traffic-related air pollutant exposure, raster or inverse distance-weighted interpolations are superior to nearest neighbor approaches, and interpolations between receptors and points of interest should not exceed about 40 m near major roads, and 100 m at larger distances. For census tracts and ZIP codes, average exposures are overestimated since few individuals live very near major roads, the range of concentrations is compressed, most exposures are misclassified, and high concentrations near roads are entirely omitted. While smaller zones improve performance considerably, even block-level data can misclassify many individuals. To estimate exposures and impacts of traffic

  2. Radiofrequency and health. Expertise update. Opinion of the ANSES. Collective expertise report

    International Nuclear Information System (INIS)

    Cardis, Elisabeth; Dore, Jean-Francois; Marc-Vergnes, Jean-Pierre; Agnani, Jean-Benoit; Bruguiere, Pierre; Crouzier, David; Debaz, Josquin; Debuire, Brigitte; Deltour, Isabelle; LE Drean, Yves; Ledoigt, Gerard; Letertre, Thierry; Marchand, Dorothee; Massardier-Pilonchery, Amelie; Nadi, Mustapha; Pereira De Vasconcelos, Anne; Hours, Martine; Fite, Johanna; Merckel, Olivier; Roth, Olivia; Vergriette, Benoit; Saddoki, Sophia

    2013-10-01

    In a context of development of new technologies of wireless communications, and therefore of radio-electric signals used to transmit information, this voluminous document reports a detailed study on the effects of radiofrequency on health. It is notably based on a large literature survey and on an assessment of the level of proof of these effects by experts (proved, possible, probable, insufficiently proved, or no effect on mankind). These effects can be either biological or on health. The report presents the context, scope and modalities of the expertise study, presents the main artificial and natural sources of radiofrequency radiation, gives a detailed presentation of new exposure sources (new signals, new radio-electric networks and their applications like mobile phones, pads, mobile television, local wireless networks, RFID, so on). It describes metrology and dose measurement techniques for electromagnetic fields (exposure characterization in laboratory, characterization of the electromagnetic environment, individual exposure measurement devices, digital dosimetry). It addresses the efficiency of anti-wave devices. The next part presents the literature survey (method, analysis, results). The authors then report an assessment of the risk level related to radio-frequencies for the central nervous system (neurotoxicity mechanisms, cognitive functions, memory and behaviour, sleep and circadian rhythms, hearing functions, neurological and neuro-degenerative diseases), and an assessment of the risk level of radio-frequencies for other non-carcinogenic effects (possible mechanisms, reproduction, immunology, endocrine system, and so on). They discuss the researches on potential carcinogenic mechanisms. They give an overview of the evolutions of regulations and management measures in France, and propose a set of recommendations

  3. Weight-of-evidence evaluation of short-term ozone exposure and cardiovascular effects.

    Science.gov (United States)

    Goodman, Julie E; Prueitt, Robyn L; Sax, Sonja N; Lynch, Heather N; Zu, Ke; Lemay, Julie C; King, Joseph M; Venditti, Ferdinand J

    2014-10-01

    There is a relatively large body of research on the potential cardiovascular (CV) effects associated with short-term ozone exposure (defined by EPA as less than 30 days in duration). We conducted a weight-of-evidence (WoE) analysis to assess whether it supports a causal relationship using a novel WoE framework adapted from the US EPA's National Ambient Air Quality Standards causality framework. Specifically, we synthesized and critically evaluated the relevant epidemiology, controlled human exposure, and experimental animal data and made a causal determination using the same categories proposed by the Institute of Medicine report Improving the Presumptive Disability Decision-making Process for Veterans ( IOM 2008). We found that the totality of the data indicates that the results for CV effects are largely null across human and experimental animal studies. The few statistically significant associations reported in epidemiology studies of CV morbidity and mortality are very small in magnitude and likely attributable to confounding, bias, or chance. In experimental animal studies, the reported statistically significant effects at high exposures are not observed at lower exposures and thus not likely relevant to current ambient ozone exposures in humans. The available data also do not support a biologically plausible mechanism for CV effects of ozone. Overall, the current WoE provides no convincing case for a causal relationship between short-term exposure to ambient ozone and adverse effects on the CV system in humans, but the limitations of the available studies preclude definitive conclusions regarding a lack of causation. Thus, we categorize the strength of evidence for a causal relationship between short-term exposure to ozone and CV effects as "below equipoise."

  4. Ecological risk of anthropogenic pollutants to reptiles: Evaluating assumptions of sensitivity and exposure

    International Nuclear Information System (INIS)

    Weir, Scott M.; Suski, Jamie G.; Salice, Christopher J.

    2010-01-01

    A large data gap for reptile ecotoxicology still persists; therefore, ecological risk assessments of reptiles usually incorporate the use of surrogate species. This necessitates that (1) the surrogate is at least as sensitive as the target taxon and/or (2) exposures to the surrogate are greater than that of the target taxon. We evaluated these assumptions for the use of birds as surrogates for reptiles. Based on a survey of the literature, birds were more sensitive than reptiles in less than 1/4 of the chemicals investigated. Dietary and dermal exposure modeling indicated that exposure to reptiles was relatively high, particularly when the dermal route was considered. We conclude that caution is warranted in the use of avian receptors as surrogates for reptiles in ecological risk assessment and emphasize the need to better understand the magnitude and mechanism of contaminant exposure in reptiles to improve exposure and risk estimation. - Avian receptors are not universally appropriate surrogates for reptiles in ecological risk assessment.

  5. Combination acetabular radiofrequency ablation and cementoplasty using a navigational radiofrequency ablation device and ultrahigh viscosity cement: technical note.

    Science.gov (United States)

    Wallace, Adam N; Huang, Ambrose J; Vaswani, Devin; Chang, Randy O; Jennings, Jack W

    2016-03-01

    Percutaneous radiofrequency ablation and cementoplasty is an alternative palliative therapy for painful metastases involving axial load-bearing bones. This technical report describes the use of a navigational radiofrequency probe to ablate acetabular metastases from an anterior approach followed by instillation of ultrahigh viscosity cement under CT-fluoroscopic guidance. The tumor ablation databases of two institutions were retrospectively reviewed to identify patients who underwent combination acetabular radiofrequency ablation and cementoplasty using the STAR Tumor Ablation and StabiliT Vertebral Augmentation Systems (DFINE; San Jose, CA). Pre-procedure acetabular tumor volume was measured on cross-sectional imaging. Pre- and post-procedure pain scores were measured using the Numeric Rating Scale (10-point scale) and compared. Partial pain improvement was categorically defined as ≥ 2-point pain score reduction. Patients were evaluated for evidence of immediate complications. Electronic medical records were reviewed for evidence of delayed complications. During the study period, 12 patients with acetabular metastases were treated. The median tumor volume was 54.3 mL (range, 28.3-109.8 mL). Pre- and post-procedure pain scores were obtained from 92% (11/12) of the cohort. The median pre-procedure pain score was 8 (range, 3-10). Post-procedure pain scores were obtained 7 days (82%; 9/11), 11 days (9.1%; 1/11) or 21 days (9.1%; 1/11) after treatment. The median post-treatment pain score was 3 (range, 1-8), a statistically significant difference compared with pre-treatment (P = 0.002). Categorically, 73% (8/11) of patients reported partial pain relief after treatment. No immediate symptomatic complications occurred. Three patients (25%; 3/12) were discharged to hospice within 1 week of treatment. No delayed complications occurred in the remaining 75% (9/12) of patients during median clinical follow-up of 62 days (range, 14-178 days). Palliative percutaneous

  6. Effects of GSM-like radiofrequency irradiation during the oogenesis and spermiogenesis of Xenopus laevis.

    Science.gov (United States)

    Boga, Ayper; Emre, Mustafa; Sertdemir, Yasar; Uncu, İbrahim; Binokay, Secil; Demirhan, Osman

    2016-07-01

    We aimed to evaluate the effect of GSM-like radiofrequency electromagnetic radiation (RF-EMR) on the oogenesis, and spermiogenesis of Xenopus laevis, and so the development of the embryos obtained from Normal Females+Normal Males (i.e. "N(F)+N(M)"); Normal Females+RF-exposed Males (i.e. "N(F)+RF(M)"); RF-exposed Female+Normal Male (i.e. "RF(F)+N(M)"); and RF-exposed Female+RF-exposed Male (i.e. "RF(F)+RF(M)". Various, assessments were performed to determine potential teratogenic effects and mortality, body growth and behavior on first generation embryos. After exposing adults frogs of both sexes to 900MHz RF-EMR (at 1.0W/kg) for 8h a day over a 5-week period, the embryos' specific energy absorption rate (SAR) was calculated. In our present study (control group; 2.2% abnormal, 0.0% dead); with the N(F)+RF(M) combination, the long-term exposure of adult males to GSM-like radiation at 900MHz (RF: 2W) for 5 week/8h/day resulted in normal, abnormal and dead embryo ratios of 88.3%, 3.3% and 8.3%, respectively (poogenesis exhibited a more aggressive behavior compared to the control group. Cell phones radiation can thus lead to detrimental effects in humans' male and female reproductive cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Radiofrequency ablation of hepatocellular carcinoma: Mono or multipolar?

    Science.gov (United States)

    Cartier, Victoire; Boursier, Jérôme; Lebigot, Jérôme; Oberti, Frédéric; Fouchard-Hubert, Isabelle; Aubé, Christophe

    2016-03-01

    Thermo-ablation by radiofrequency is recognized as a curative treatment for early-stage hepatocellular carcinoma. However, local recurrence may occur because of incomplete peripheral tumor destruction. Multipolar radiofrequency has been developed to increase the size of the maximal ablation zone. We aimed to compare the efficacy of monopolar and multipolar radiofrequency for the treatment of hepatocellular carcinoma and determine factors predicting failure. A total of 171 consecutive patients with 214 hepatocellular carcinomas were retrospectively included. One hundred fifty-eight tumors were treated with an expandable monopolar electrode and 56 with a multipolar technique using several linear bipolar electrodes. Imaging studies at 6 weeks after treatment, then every 3 months, assessed local effectiveness. Radiofrequency failure was defined as persistent residual tumor after two sessions (primary radiofrequency failure) or local tumor recurrence during follow-up. This study received institutional review board approval (number 2014/77). Imaging showed complete tumor ablation in 207 of 214 lesions after the first session of radiofrequency. After a second session, only two cases of residual viable tumor were observed. During follow-up, there were 46 local tumor recurrences. Thus, radiofrequency failure occurred in 48/214 (22.4%) cases. By multivariate analysis, technique (P radiofrequency failure. Failure rate was lower with the multipolar technique for tumors radiofrequency, multipolar radiofrequency improves tumor ablation with a subsequent lower rate of local tumor recurrence. © 2015 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  8. Measurement of radioactive aerosol behavior during dismantling and reflection to the exposure dose evaluation - 16107

    International Nuclear Information System (INIS)

    Iguchi, Yukihiro; Kato, Masami

    2009-01-01

    Radioactive aerosol disperses slightly via contamination prevention systems such as control enclosures and filters when the nuclear installation is dismantled, and it might impact the environment. Therefore, when decommissioning is planned, it is necessary to assess the safety such as exposure dose evaluation to the public. For the radioactive aerosol, it is possible that the dispersion ratio is different according to the contamination condition, the dismantlement method of the material, nuclides (elements), etc. The radiation exposure evaluation for the decommissioning plan has been executed by operators in Japan based on a number of experiments (mostly cold tests) and overseas results. The decommissioning is now being carried out at the Tokai Power Station (GCR) and Fugen Decommissioning Engineering Center in Japan. In this study, the results data is acquired at the decommissioning sites, and the methodology and data for the exposure dose evaluation are verified and confirmed. These examination results will lead to the upgrading and improvement of the exposure evaluation methodology. In particular, the dismantlement work of connected piping of the heat exchanger (steam generator) was executed in the Tokai Power Station in 2008. In this study, we paid attention to the radionuclides of Co-60 and Cs-137 that adhered to piping, and the dispersion behavior of aerosol was measured and contamination prevention effect was assured. As a result, the data show that the cesium concentrates about four times higher than cobalt. Moreover, the effects of the prevention measures of contamination were confirmed and the behavior of the radioactive aerosol became clear and the effective findings about the dose evaluation of the dismantling were collected. (authors)

  9. Evaluation of recommended REACH exposure modeling tools and near-field, far-field model in assessing occupational exposure to toluene from spray paint.

    Science.gov (United States)

    Hofstetter, Elizabeth; Spencer, John W; Hiteshew, Kathleen; Coutu, Michelle; Nealley, Mark

    2013-03-01

    Predictive modeling is an available tool to assess worker exposures to a variety of chemicals in different industries and product-use scenarios. The European Chemical Agency (ECHA)'s guidelines for manufacturers to fulfill the European Union's legal requirements pursuant to the Registration, Evaluation, Authorization, and Restriction of Chemicals (REACH) initiative include recommendations for the use of modeling to predict worker exposures. ECHA recommends different models for different target populations (i.e. workers, consumers, environment) and routes of exposure (i.e. skin absorption, ingestion, inhalation), and presents them hierarchically, with Tier 1 models presented as the most simplistic, conservative models and Tier 2 models recommended for further intensive evaluation of substances or preparations. In order to assess these models for one exposure (product-use) scenario, a simulation of the scenario was completed in a controlled environment and the measured results were compared with the modeling outputs. The authors predicted, based on the design of the modeling tools, that all models would overestimate worker exposures under the simulated product-use scenario, with the lower-tiered model producing the most conservative estimate of exposure. In this study, a Tier 1 model and a Tier 2 model were evaluated for comparison with the near-field, far-field (NF-FF) deterministic model and measured experimental results in a real-time worker inhalation exposure assessment. Modeling was conducted prior to actual air monitoring. The exposure scenario that was evaluated involved the application of a toluene-containing spray paint to a work surface. Air samples were collected to evaluate short-term (15-min) and long-term (240-min) exposures. Eight-hour time-weighted averages (8-h TWAs) were calculated and compared with the modeling outputs from the recommended REACH modeling tools and the NF-FF model. A comparison of each of the modeling tools with measured

  10. CT-guided percutaneous radiofrequency denervation of the sacroiliac joint

    Energy Technology Data Exchange (ETDEWEB)

    Gevargez, A.; Schirp, S.; Braun, M. [Department of Radiology and Microtherapy, University of Witten/Herdecke, Bochum (Germany); Groenemeyer, D. [Department of Radiology and Microtherapy, University of Witten/Herdecke, Bochum (Germany); EFMT Development and Research Center for Microtherapy, Bochum (Germany)

    2002-06-01

    Defining the origin of low back pain is a challenging task. Among a variety of factors the sacroiliac joint (SIJ) is a possible pain generator, although precise diagnosis is difficult. Joint blocks may reduce pain, but are, in cases, of only temporary effect. This study was conducted to evaluate CT-guided percutaneous radiofrequency denervation of the sacroiliac joint in patients with low back pain. The procedure was performed on 38 patients who only temporarily responded to CT-guided SIJ blocks. The denervation was carried out in the posterior interosseous sacroiliac ligaments and on the dorsal rami of the fifth spinal nerve. All interventions were carried out under CT guidance as out-patient therapies. Three months after the therapy, 13 patients (34.2%) were completely free of pain. Twelve patients (31.6%) reported on a substantial pain reduction, 7 patients (18.4%) had obtained a slight and 3 patients (7.9%) no pain reduction. The data of 3 patients (7.9%) was missing. There were no intra- or postoperative complications. Computed tomography-guided percutaneous radiofrequency denervation of the sacroiliac joint appears safe and effective. The procedure may be a useful therapeutic modality, especially in patients with chronic low back pain, who only temporarily respond to therapeutic blocks. (orig.)

  11. Radiofrequency volume reduction of gastrocnemius muscle hypertrophy for cosmetic purposes.

    Science.gov (United States)

    Park, Young Jin; Jo, Yong Woo; Bang, Sa Ik; Kim, Hyung Joon; Lim, So Young; Mun, Goo Hyun; Hyon, Won Sok; Oh, Kap Sung

    2007-01-01

    Muscularly prominent calves, caused mainly by hypertrophy of the gastrocnemius muscle (GCM), are prevalent among Asian women, and this condition can be a significant factor leading to psychological stress. The authors have devised a method for contouring the calf using radiofrequency (RF) applications to the GCMs to correct thick, muscular legs. This study was performed to investigate the effects of RF energy in reducing enlarged GCMs for 250 patients (249 women and 1 man) who sought aesthetic consultation for problems such as thick, muscular, asymmetric, or bowed calves. The operations were performed from June 2004 to April 2006. The patients first received a local anesthetic and sedation. After application of RF current, the prominent muscular contours improved, and the GCMs were contoured to an appropriate proportional volume. The range of the reductions in the calf circumferences at their thickest levels was 1 to 6 cm (mean, 2.5 cm) during the follow-up visits 6 months after the procedures. Most of the patients could return to their activities of daily living, except for exercise, after 1 to 7 days, and they were satisfied with the improved aesthetic contour lines of their lower legs. Clinical photography and ultrasonic examination were performed, and the leg circumferences were measured. Radiofrequency-induced coagulation tissue necrosis of the muscles caused no functional disabilities, and the clinical improvement was well maintained after the treatments for up to 17 months of follow-up evaluation.

  12. CT-guided percutaneous radiofrequency denervation of the sacroiliac joint

    International Nuclear Information System (INIS)

    Gevargez, A.; Schirp, S.; Braun, M.; Groenemeyer, D.

    2002-01-01

    Defining the origin of low back pain is a challenging task. Among a variety of factors the sacroiliac joint (SIJ) is a possible pain generator, although precise diagnosis is difficult. Joint blocks may reduce pain, but are, in cases, of only temporary effect. This study was conducted to evaluate CT-guided percutaneous radiofrequency denervation of the sacroiliac joint in patients with low back pain. The procedure was performed on 38 patients who only temporarily responded to CT-guided SIJ blocks. The denervation was carried out in the posterior interosseous sacroiliac ligaments and on the dorsal rami of the fifth spinal nerve. All interventions were carried out under CT guidance as out-patient therapies. Three months after the therapy, 13 patients (34.2%) were completely free of pain. Twelve patients (31.6%) reported on a substantial pain reduction, 7 patients (18.4%) had obtained a slight and 3 patients (7.9%) no pain reduction. The data of 3 patients (7.9%) was missing. There were no intra- or postoperative complications. Computed tomography-guided percutaneous radiofrequency denervation of the sacroiliac joint appears safe and effective. The procedure may be a useful therapeutic modality, especially in patients with chronic low back pain, who only temporarily respond to therapeutic blocks. (orig.)

  13. Consequences of the magnetic field, sonic and radiofrequency waves and intense pulsed light on the labeling of blood constituents with technetium-99m

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Patricia Froes; Costa, Iris do Ceu Clara; Brandao-Neto, Jose; Medeiros, Aldo da Cunha [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Programa de Pos-graduacao em Ciencias da Saude; Santos-Filho, Sebastiao David; Adenilson de Souza da Fonseca; Bernardo-Filho, Mario [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Lab. de Radiofarmacia Experimental; Ariel Ronzio, Oscar [Universidad de Buenos Aires (Argentina); Bonelli, Ludmila [Universidade Salgado de Oliveira, Belo Horizonte, MG (Brazil)

    2007-09-15

    Sources of magnetic field, radiofrequency and audible sonic waves and pulsed light have been used in physiotherapy to treat different disorders. In nuclear medicine, blood constituents(Bl-Co) are labeled with technetium-99m ({sup 99m}Tc) are used. This study evaluated the consequences of magnetic field, radiofrequency and audible sonic waves and intense pulsed light sources on the labeling of Bl-Co with {sup 99m}Tc. Blood from Wistar rats was exposed to the cited sources. The labeling of Bl-Co with {sup 99m}Tc was performed. Blood not exposed to the physical agents was used(controls). Data showed that the exposure to the different studied sources did not alter significantly (p>0.05) the labeling of Bl-Co. Although the results were obtained with animals, the data suggest that no alteration on examinations performed with Bl-Co labeled with {sup 99m}Tc after exposition to the cited agents. The biological consequences associated with these agents would be not capable to interfere with some properties of the Bl-Co. (author)

  14. Endovascular Radiofrequency Ablation for Varicose Veins

    Science.gov (United States)

    2011-01-01

    treatment plan. The RFA procedure involves the introduction of a guide wire into the target vein under ultrasound guidance followed by the insertion of an introducer sheath through which the RFA catheter is advanced. Once satisfactory positioning has been confirmed with ultrasound, a tumescent anaesthetic solution is injected into the soft tissue surrounding the target vein along its entire length. This serves to anaesthetize the vein, insulate the heat from damaging adjacent structures, including nerves and skin and compresses the vein increasing optimal contact of the vessel wall with the electrodes or expanded prongs of the RF device. The RF generator is then activated and the catheter is slowly pulled along the length of the vein. At the end of the procedure, hemostasis is then achieved by applying pressure to the vein entry point. Adequate and proper compression stockings and bandages are applied after the procedure to reduce the risk of venous thromboembolism and to reduce postoperative bruising and tenderness. Patients are encouraged to walk immediately after the procedure. Follow-up protocols vary, with most patients returning 1 to 3 weeks later for an initial follow-up visit. At this point, the initial clinical result is assessed and occlusion of the treated vessels is confirmed with ultrasound. Patients often have a second follow-up visit 1 to 3 months following RFA at which time clinical evaluation and ultrasound are repeated. If required, additional procedures such as phlebectomy or sclerotherapy may be performed during the RFA procedure or at any follow-up visits. Regulatory Status The Closure System® radiofrequency generator for endovascular thermal ablation of varicose veins was approved by Health Canada as a class 3 device in March 2005, registered under medical device license 67865. The RFA intravascular catheter was approved by Health Canada in November 2007 for the ClosureFast catheter, registered under medical device license 16574. The Closure System

  15. Evaluation of dose exposure from irradiated samples at TRIGA PUSPATI reactor (RTP)

    International Nuclear Information System (INIS)

    Muhd Husamuddin Abdul Khalil; Julia Abdul Karim; Naim Syauqi Hamzah; Mohamad Hairie Rabir; Mohd Amin Sharifuldin Salleh

    2010-01-01

    An evaluation has been made to data of irradiated samples for the type of sample requested for activation at RTP. Sample types are grouped with percentage of total throughputs to rule out the weight percent of every respective group. The database consists of radionuclide inventory of short, intermediate and long half-life and high activity radionuclides such as Br and Au have been identified. Evaluation of gamma exposure using Micro shield has also been made to pattern the trend of gamma exposure at experimental facilities and to ensure radiological effect towards safety and health is limited per Radiation Protection (Basic Safety Standard) Regulation 1988. This analysis places an important parameter to improve the design accuracy of shielding design in assuring safety, reliability and economy. (author)

  16. Quantitative evaluation of personal exposure to UV radiation of workers and general public

    International Nuclear Information System (INIS)

    Sisto, R.; Borra, M.; Casale, G. R.; Militello, A.; Siani, A. M.

    2009-01-01

    Due to meteorological conditions variability and to the variability of exposure patterns, which can be largely different during a working day, personal dosemeters use can be necessary to obtain a correct quantitative evaluation of the radiation dose absorbed by an exposed worker. Different classes of personal dosemeters exist and, among them, electronic dosemeters and poly-sulphone film dosemeters. An experimental campaign is presented conduced in a cultivated area of Tuscany and some aspects are discussed about an experimental campaign performed on a population of volunteers on a central Italy beach near Rome. The aim of the present work is to show some relevant issues in a dosimetric approach to the exposure evaluation of outdoor workers and, in general, of the public during recreational activities. (authors)

  17. [Evaluation of acoustic effectiveness of personnel protectors from extra-aural exposure to aviation noise].

    Science.gov (United States)

    Dragan, S P; Soldatov, S K; Bogomolov, A V; Drozdov, S V; Poliakov, N M

    2013-01-01

    Purpose of the investigation was to validate testing acoustic effectiveness of a personnel vest-like protector (PP) from extra-aural exposure to aviation noise. Levels of aviation noise for PP testing were determined through calculation. Vest effectiveness in protecting from acoustic vibration generated by high-intensity aviation noise was evaluated both in laboratory and field tests. For comparison analysis, PP was also tested with a dummy exposed on a special tester, i.e. acoustic interferometer.

  18. Evaluation of total risk exposure and insurance premiums in the maritime industry

    OpenAIRE

    Knapp, Sabine; Heij, Christiaan

    2016-01-01

    textabstractThis study provides an empirical evaluation of maritime risk exposure expressed as the monetary value at risk (MVR), which incorporates life of crew and passengers, vessel value of hull and machinery, carried cargo value, third party liabilities, and potential external damages like pollution. MVR is based on individual safety quality data of about 130,000 vessels, on insurable values related to various potential damages, and on proxies for fractions of values lost at incidents. MV...

  19. Evaluating exposure and potential effects on honeybee brood (Apis mellifera) development using glyphosate as an example

    OpenAIRE

    Thompson, Helen M; Levine, Steven L; Doering, Janine; Norman, Steve; Manson, Philip; Sutton, Peter; von M?rey, Georg

    2014-01-01

    This study aimed to develop an approach to evaluate potential effects of plant protection products on honeybee brood with colonies at realistic worst-case exposure rates. The approach comprised 2 stages. In the first stage, honeybee colonies were exposed to a commercial formulation of glyphosate applied to flowering Phacelia tanacetifolia with glyphosate residues quantified in relevant matrices (pollen and nectar) collected by foraging bees on days 1, 2, 3, 4, and 7 postapplication and glypho...

  20. Evaluation of the Effect of Short-Term Cadmium Exposure on ...

    African Journals Online (AJOL)

    This study evaluated the effect of short-term cadmium exposure on brackish water shrimp-Palaemonetes africanus. Tests were carried out by exposing the shrimps to the test solutions containing various concentrations of the cadmium (0, 0.1, 1.0, 4.0, 6.0, 8.0, 10.0, and 100.0) mg/l using the semi-static agitation test ...

  1. Retrospective evaluation of exposure index (EI) values from plain radiographs reveals important considerations for quality improvement

    Energy Technology Data Exchange (ETDEWEB)

    Mothiram, Ursula; Brennan, Patrick C; Robinson, John; Lewis, Sarah J [Medical Imaging Optimisation and Perception Group (MIOPeG), Discipline of Medical Radiation Sciences, Faculty of Health Science, University of Sydney, Sydney (Australia); Moran, Bernadette [Department of Clinical Medicine, Trinity College Dublin, Dublin (Ireland); Medical Imaging Optimisation and Perception Group (MIOPeG), Discipline of Medical Radiation Sciences, Faculty of Health Science, University of Sydney, Sydney (Australia)

    2013-12-15

    Following X-ray exposure, radiographers receive immediate feedback on detector exposure in the form of the exposure index (EI). To identify whether radiographers are meeting manufacturer-recommended EI (MREI) ranges for routine chest, abdomen and pelvis X-ray examinations under a variety of conditions and to examine factors affecting the EI. Data on 5000 adult X-ray examinations including the following variables were collected: examination parameters, EI values, patient gender, date of birth, date and time of examination, grid usage and the presence of implant or prosthesis. Descriptive statistics were used to summarize each data set and the Mann–Whitney U test was used to determine significant differences, with P < 0.05 indicating significance for all tests. Most examinations demonstrated EI values that were outside the MREI ranges, with significantly higher median EI values recorded for female patient radiographs than those for male patients for all manufacturers, indicating higher detector exposures for all units except for Philips digital radiography (DR), where increased EI values indicate lower exposure (P = 0.01). Median EI values for out of hours radiography were also significantly higher compared with normal working hours for all technologies (P ≤ 0.02). Significantly higher median EI values were demonstrated for Philips DR chest X-rays without as compared to those with the employment of a grid (P = 0.03), while significantly lower median EI values were recorded for Carestream Health computed radiography (CR) chest X-rays when an implant or prosthesis was present (P = 0.02). Non-adherence to MREIs has been demonstrated with EI value discrepancies being dependent on patient gender, time/day of exposure, grid usage and the presence of an implant or prosthesis. Retrospective evaluation of EI databases is a valuable tool to assess the need of quality improvement in routine DR.

  2. Evaluation and comparison of urinary metabolic biomarkers of exposure for the jet fuel JP-8.

    Science.gov (United States)

    B'Hymer, Clayton; Krieg, Edward; Cheever, Kenneth L; Toennis, Christine A; Clark, John C; Kesner, James S; Gibson, Roger; Butler, Mary Ann

    2012-01-01

    A study of workers exposed to jet fuel propellant 8 (JP-8) was conducted at U.S. Air Force bases and included the evaluation of three biomarkers of exposure: S-benzylmercapturic acid (BMA), S-phenylmercapturic acid (PMA), and (2-methoxyethoxy)acetic acid (MEAA). Postshift urine specimens were collected from various personnel categorized as high (n = 98), moderate (n = 38) and low (n = 61) JP-8 exposure based on work activities. BMA and PMA urinary levels were determined by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and MEAA urinary levels were determined by gas chromatography-mass spectrometry (GC-MS). The numbers of samples determined as positive for the presence of the BMA biomarker (above the test method's limit of detection [LOD = 0.5 ng/ml]) were 96 (98.0%), 37 (97.4%), and 58 (95.1%) for the high, moderate, and low (control) exposure workgroup categories, respectively. The numbers of samples determined as positive for the presence of the PMA biomarker (LOD = 0.5 ng/ml) were 33 (33.7%), 9 (23.7%), and 12 (19.7%) for the high, moderate, and low exposure categories. The numbers of samples determined as positive for the presence of the MEAA biomarker (LOD = 0.1 μ g/ml) were 92 (93.4%), 13 (34.2%), and 2 (3.3%) for the high, moderate, and low exposure categories. Statistical analysis of the mean levels of the analytes demonstrated MEAA to be the most accurate or appropriate biomarker for JP-8 exposure using urinary concentrations either adjusted or not adjusted for creatinine; mean levels of BMA and PMA were not statistically significant between workgroup categories after adjusting for creatinine.

  3. Retrospective evaluation of exposure index (EI) values from plain radiographs reveals important considerations for quality improvement

    International Nuclear Information System (INIS)

    Mothiram, Ursula; Brennan, Patrick C; Robinson, John; Lewis, Sarah J; Moran, Bernadette

    2013-01-01

    Following X-ray exposure, radiographers receive immediate feedback on detector exposure in the form of the exposure index (EI). To identify whether radiographers are meeting manufacturer-recommended EI (MREI) ranges for routine chest, abdomen and pelvis X-ray examinations under a variety of conditions and to examine factors affecting the EI. Data on 5000 adult X-ray examinations including the following variables were collected: examination parameters, EI values, patient gender, date of birth, date and time of examination, grid usage and the presence of implant or prosthesis. Descriptive statistics were used to summarize each data set and the Mann–Whitney U test was used to determine significant differences, with P < 0.05 indicating significance for all tests. Most examinations demonstrated EI values that were outside the MREI ranges, with significantly higher median EI values recorded for female patient radiographs than those for male patients for all manufacturers, indicating higher detector exposures for all units except for Philips digital radiography (DR), where increased EI values indicate lower exposure (P = 0.01). Median EI values for out of hours radiography were also significantly higher compared with normal working hours for all technologies (P ≤ 0.02). Significantly higher median EI values were demonstrated for Philips DR chest X-rays without as compared to those with the employment of a grid (P = 0.03), while significantly lower median EI values were recorded for Carestream Health computed radiography (CR) chest X-rays when an implant or prosthesis was present (P = 0.02). Non-adherence to MREIs has been demonstrated with EI value discrepancies being dependent on patient gender, time/day of exposure, grid usage and the presence of an implant or prosthesis. Retrospective evaluation of EI databases is a valuable tool to assess the need of quality improvement in routine DR

  4. Anthropogenic radiofrequency electromagnetic fields as an emerging threat to wildlife orientation.

    Science.gov (United States)

    Balmori, Alfonso

    2015-06-15

    The rate of scientific activity regarding the effects of anthropogenic electromagnetic radiation in the radiofrequency (RF) range on animals and plants has been small despite the fact that this topic is relevant to the fields of experimental biology, ecology and conservation due to its remarkable expansion over the past 20 years. Current evidence indicates that exposure at levels that are found in the environment (in urban areas and near base stations) may particularly alter the receptor organs to orient in the magnetic field of the earth. These results could have important implications for migratory birds and insects, especially in urban areas, but could also apply to birds and insects in natural and protected areas where there are powerful base station emitters of radiofrequencies. Therefore, more research on the effects of electromagnetic radiation in nature is needed to investigate this emerging threat. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Fraxelated radiofrequency device for acne scars

    Science.gov (United States)

    Rao, Babar K.; Khokher, Sairah

    2012-09-01

    Acne scars can be improved with various treatments such as topical creams, chemical peels, dermal fillers, microdermabrasion, laser, and radiofrequency devices. Some of these treatments especially lasers and deep chemical peels can have significant side effects such as post inflammatory hyperpigmentation in darker skin types. Fraxelated RF Laser devices have been reported to have lower incidence of side effects in all skin phototypes. Nine patients between ages 18 and 35 of various skin phototypes were selected from a private practice and treated with a RF fraxelated device (E-matrix) for acne scars. Outcomes were measured by physician observation, subjective feedback received by patients, and comparison of before and after photographs. In this small group of patients with various skin phototypes, fraxelated radiofrequency device improved acne scars with minimal side effects and downtime.

  6. [Newborn outcomes after radiofrequency ablation for selective reduction in the complicated monochorionic pregnancies].

    Science.gov (United States)

    Panciatici, M; Tosello, B; Blanc, J; Haumonté, J-B; D'Ercole, C; Gire, C

    2017-04-01

    To describe perinatal data and to evaluate the neonatal neurological outcome of monochorionic twin pregnancies with selective termination by radiofrequency ablation. Retrospective data of perinatal data for nine consecutive monochorionic pregnancies eligible for radiofrequency ablation from January 2013 to August 2015 were collected. A prospective observational study of the neurological outcome of nine children was conducted using the Ages & Stages Questionnaire (ASQ), 2nd edition, French version, adapted to the age. The radiofrequency procedures were performed at a mean gestational age (GA) of 21.4 weeks (±7 weeks). The indications for a selective interruption of a pregnancy were: acardiac twin (n=4), brain malformation (n=1), severe intrauterine growth restriction (IUGR) with massive cerebral ischemia in the context of twin-twin transfusion syndrome grade III (n=1), severe selective IUGR associated with a polymalformative syndrome (n=1) and severe selective IUGR (n=2). The mean GA at birth was 36.7 weeks GA (±3.8 weeks). No infant showed neurological neonatal morbidity. Any ASQ area explored was pathological (<-2SD) for the nine children (mean age at follow-up [±SD], 14.8 months [±8.8 months]). This work constitutes a preliminary study for developing long-term follow-up and early care programs for those children born subsequent to a radiofrequency ablation for selective reduction. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  7. Long-wave plasma radiofrequency ablation for treatment of xanthelasma palpebrarum.

    Science.gov (United States)

    Baroni, Adone

    2018-03-01

    Xanthelasma palpebrarum is the most common type of xanthoma affecting the eyelids. It is characterized by asymptomatic soft yellowish macules, papules, or plaques over the upper and lower eyelids. Many treatments are available for management of xanthelasma palpebrarum, the most commonly used include surgical excision, ablative CO 2 or erbium lasers, nonablative Q-switched Nd:YAG laser, trichloroacetic acid peeling, and radiofrequency ablation. This study aims to evaluate the effectiveness of RF ablation in the treatment of xanthelasma palpebrarum, with D.A.S. Medical portable device (Technolux, Italia), a radiofrequency tool working with long-wave plasma energy and without anesthesia. Twenty patients, 15 female and 5 male, affected by xanthelasma palpebrarum, were enrolled for long-wave plasma radiofrequency ablation treatment. The treatment consisted of 3/4 sessions that were carried out at intervals of 30 days. Treatments were well tolerated by all patients with no adverse effects and optimal aesthetic results. The procedure is very fast and can be performed without anesthesia because of the low and tolerable pain stimulation. Long-wave plasma radiofrequency ablation is an effective option for treatment of xanthelasma palpebrarum and adds an additional tool to the increasing list of medical devices for aesthetic treatments. © 2018 Wiley Periodicals, Inc.

  8. Radiofrequency denervation of the hip joint for pain management: case report and literature review.

    Science.gov (United States)

    Gupta, Gaurav; Radhakrishna, Mohan; Etheridge, Paul; Besemann, Markus; Finlayson, Robert J

    2014-01-01

    A 55-year-old male presented with severe pain and functional limitations as a result of left hip osteoarthritis. He had failed multiple treatments while waiting for a hip arthroplasty, including physical therapy, medications, and various intra-articular injections. Thermal radiofrequency lesioning of the obturator and femoral articular branches to the hip joint was offered in the interim. To our knowledge, this is the first report to describe an inferior-lateral approach for lesioning the obturator branch, the clinical application of successive lesions to increase denervation area, and outcomes in a patient receiving a second treatment with previously good results. To discuss relevant and technical factors for this specific case, we reviewed previous literature on hip joint radiofrequency and critically evaluated previous anatomic studies in the context of radiofrequency. The first treatment provided significant benefit for a period of 6 months. A second treatment was employed providing only mild to moderate benefit until his joint replacement surgery 4 months later. Literature review revealed studies of low quality secondary to small sample sizes, patient selection methodology, inclusion of patients with heterogenous etiologies for pain, variable needle placement techniques, and lack of measurement of functional outcomes. Case report and low quality studies in existing literature. Hip joint radiofrequency denervation is a promising avenue for adjunctive treatment of hip pain. Further cadaveric studies are required to clarify a multitude of technical parameters. Once these are well defined, future clinical studies should consider pain, functional, and economic outcomes in their design.

  9. Evaluation of radiation exposure from patients with thyroid disease by iodine-131 therapy

    International Nuclear Information System (INIS)

    Li Xianfeng; Lu Keyi; Duan Lian

    2004-01-01

    Purpose: To evaluate the radiation exposure to the individuals other than patients with thyroid disease, who had received radioiodine (iodine-131) therapy and had turned into a specific 'radiant point'. Methods: 107 outpatients or inpatients, with iodine-131 therapy had been investigated and followed up by telephone and outpatients. There were 117 times treatment (68 females, 49 males, mean age 41 years old), including the patients with hyperthyroidism (39 females, 40 males), thyroid cancer (27 females, 8 males), toxic thyroid adenoma (1 female and 1 male) and nontoxic nodular goiter(1 female). According to the personal condition of the patients, we attained the percentage of thyroid iodine-131 uptake (U), the iodine-131 dose (Q), the duration of constrained social activity, and the occupancy factor (OF) for the 3 periods (the preequilibrium, OFp; the constrained, OFc; and the unconstrained, OFuc), and the time of exposure to individuals other than patients, and to calculate the exposure dose (mSv) to the individuals. The formula is E (mSv) = Q[OFP(0.0173)+ OFC(0.537)U(1-e-0.095C)+0.023(1-U)(1-e-2.08C ) +OFUC (0.537) Ue-0.095C +0.0236(1-U)e-2.08C]. In accordance with the new recommendations of the national criteria from GB18871-2002, we evaluated the radiation safety to the individuals other than patients Results: Based on the national criteria the total effective dose equivalent to the individuals other than patients may not exceed 5 mSv. For all patients, including 79 hyperthyroidism, 2 toxic thyroid adenoma and 16 times treatment of thyroid cancer, the exposure doses to the individuals were not likely to exceed 5 mSv, but the others, including 19 times treatment of thyroid cancer and 1 nontoxic nodular goiter, the exposure doses were higher than 5 mSv. There were no difference between the part of hyperthyroidism and thyroid cancer of inpatients were compared with outpatients (P>0.05, respectively). we found that occupancy factor during the preequilibrium period

  10. Temperature-controlled irrigated tip radiofrequency catheter ablation

    DEFF Research Database (Denmark)

    Petersen, H H; Chen, X; Pietersen, Adrian

    1998-01-01

    INTRODUCTION: In patients with ventricular tachycardias due to structural heart disease, catheter ablation cures radiofrequency ablation. Irrigated tip radiofrequency ablation using power control and high infusion rates enlarges lesion......: We conclude that temperature-controlled radiofrequency ablation with irrigated tip catheters using low target temperature and low infusion rate enlarges lesion size without increasing the incidence of cratering and reduces coagulum formation of the tip....

  11. Radiofrequency Wire Recanalization of Chronically Thrombosed TIPS

    Energy Technology Data Exchange (ETDEWEB)

    Majdalany, Bill S., E-mail: bmajdala@med.umich.edu [University of Michigan Health System, Division of Interventional Radiology, Department of Radiology (United States); Elliott, Eric D., E-mail: eric.elliott@osumc.edu [The Ohio State University Wexner Medical Center, Division of Interventional Radiology, Department of Radiology (United States); Michaels, Anthony J., E-mail: Anthony.michaels@osumc.edu; Hanje, A. James, E-mail: James.Hanje@osumc.edu [The Ohio State University Wexner Medical Center, Division of Gastroenterology and Hepatology, Department of Medicine (United States); Saad, Wael E. A., E-mail: wsaad@med.umich.edu [University of Michigan Health System, Division of Interventional Radiology, Department of Radiology (United States)

    2016-07-15

    Radiofrequency (RF) guide wires have been applied to cardiac interventions, recanalization of central venous thromboses, and to cross biliary occlusions. Herein, the use of a RF wire technique to revise chronically occluded transjugular intrahepatic portosystemic shunts (TIPS) is described. In both cases, conventional TIPS revision techniques failed to revise the chronically thrombosed TIPS. RF wire recanalization was successfully performed through each of the chronically thrombosed TIPS, demonstrating initial safety and feasibility in this application.

  12. ROLE OF RADIOFREQUENCY ABLATION IN ADENOMA SEBACEUM

    Directory of Open Access Journals (Sweden)

    Ch. Madh

    2016-03-01

    Full Text Available Adenoma sebaceum, pathognomonic of tuberous sclerosis, are tiny angiofibromas which commonly occur over central part of face. Recurrence after treatment is common and hence a need for inexpensive, safe and efficient treatment is required. Radiofrequency ablation is a safe and an economical procedure and has been known to cause less scarring with good aesthetic results compared to other ablative methods such as electrocautery.

  13. The effects of 1800 MHz radiofrequency waves on lipid peroxidation in pregnant rabbits

    International Nuclear Information System (INIS)

    Tomruk, Arin; Guler, Goknur; Seyhan, Nesrin

    2008-01-01

    II (non-pregnant +RF exposed group); 3) Group III (pregnant group); 4) Group IV (pregnant + RF exposed group). For each exposure groups (Group II, Group IV) rabbits were exposed to pulsed 1800 MHz radiofrequency radiation (217 Hz GSM modulation; 20dBm) 15 min/day during a week. MDA levels were quantified by measuring the formation of thiobarbituric acid reactive substances (TBARS). TBARS levels were determined in liver tissues of rabbits by using Uchiyama and Mihara's spectrophotometric method. Statistical analyses were carried out using SPSS software (SPSS 11.5 for windows, SPSS Inc., Chicago, USA). Mann-Whitney U test were performed on the data of biochemical variables to examine the difference among groups. It was found increased TBARS levels in Group II statistically significant (p<0.004) with respect to Group I. While, it was observed that TBARS levels were found increased during pregnancy period, the effect of short-term pulsed RF exposure on TBARS levels were determined during this period. Depending on the results obtained from this study, TBARS levels were found also increased in Group IV statistically significant (p<0.006) with respect to Group II. Consequently, increased TBARS levels can be evaluated as oxidative effects of pulsed 1800 MHz RF radiation on lipids and be assumed that increased LPO products mediated by free radicals may be indicators of subsequent reactions that occur to form other oxygen toxicity in tissues. (author)

  14. Development and evaluation of probability density functions for a set of human exposure factors

    International Nuclear Information System (INIS)

    Maddalena, R.L.; McKone, T.E.; Bodnar, A.; Jacobson, J.

    1999-01-01

    The purpose of this report is to describe efforts carried out during 1998 and 1999 at the Lawrence Berkeley National Laboratory to assist the U.S. EPA in developing and ranking the robustness of a set of default probability distributions for exposure assessment factors. Among the current needs of the exposure-assessment community is the need to provide data for linking exposure, dose, and health information in ways that improve environmental surveillance, improve predictive models, and enhance risk assessment and risk management (NAS, 1994). The U.S. Environmental Protection Agency (EPA) Office of Emergency and Remedial Response (OERR) plays a lead role in developing national guidance and planning future activities that support the EPA Superfund Program. OERR is in the process of updating its 1989 Risk Assessment Guidance for Superfund (RAGS) as part of the EPA Superfund reform activities. Volume III of RAGS, when completed in 1999 will provide guidance for conducting probabilistic risk assessments. This revised document will contain technical information including probability density functions (PDFs) and methods used to develop and evaluate these PDFs. The PDFs provided in this EPA document are limited to those relating to exposure factors

  15. Development and evaluation of probability density functions for a set of human exposure factors

    Energy Technology Data Exchange (ETDEWEB)

    Maddalena, R.L.; McKone, T.E.; Bodnar, A.; Jacobson, J.

    1999-06-01

    The purpose of this report is to describe efforts carried out during 1998 and 1999 at the Lawrence Berkeley National Laboratory to assist the U.S. EPA in developing and ranking the robustness of a set of default probability distributions for exposure assessment factors. Among the current needs of the exposure-assessment community is the need to provide data for linking exposure, dose, and health information in ways that improve environmental surveillance, improve predictive models, and enhance risk assessment and risk management (NAS, 1994). The U.S. Environmental Protection Agency (EPA) Office of Emergency and Remedial Response (OERR) plays a lead role in developing national guidance and planning future activities that support the EPA Superfund Program. OERR is in the process of updating its 1989 Risk Assessment Guidance for Superfund (RAGS) as part of the EPA Superfund reform activities. Volume III of RAGS, when completed in 1999 will provide guidance for conducting probabilistic risk assessments. This revised document will contain technical information including probability density functions (PDFs) and methods used to develop and evaluate these PDFs. The PDFs provided in this EPA document are limited to those relating to exposure factors.

  16. Atmospheric Dispersion Modelling and Spatial Analysis to Evaluate Population Exposure to Pesticides from Farming Processes

    Directory of Open Access Journals (Sweden)

    Sofia Costanzini

    2018-01-01

    Full Text Available This work originates from an epidemiological study aimed to assess the correlation between population exposure to pesticides used in agriculture and adverse health effects. In support of the population exposure evaluation two models implemented by the authors were applied: a GIS-based proximity model and the CAREA atmospheric dispersion model. In this work, the results of the two models are presented and compared. Despite the proximity analysis is widely used for these kinds of studies, it was investigated how meteorology could affect the exposure assessment. Both models were applied to pesticides emitted by 1519 agricultural fields and considering 2584 receptors distributed over an area of 8430 km2. CAREA output shows a considerable enhancement in the percentage of exposed receptors, from the 4% of the proximity model to the 54% of the CAREA model. Moreover, the spatial analysis of the results on a specific test site showed that the effects of meteorology considered by CAREA led to an anisotropic exposure distribution that differs considerably from the symmetric distribution resulting by the proximity model. In addition, the results of a field campaign for the definition and planning of ground measurement of concentration for the validation of CAREA are presented. The preliminary results showed how, during treatments, pesticide concentrations distant from the fields are significantly higher than background values.

  17. Radiofrequency volumetric reduction for masseteric hypertrophy.

    Science.gov (United States)

    Jin Park, Young; Woo Jo, Yong; Bang, Sa Ik; Kim, Hyung Joon; Lim, So Young; Mun, Goo Hyun; Hyon, Won Sok; Oh, Kap Sung

    2007-01-01

    Masseteric hypertrophy occurs frequently among Asians, including Koreans, because of racial characteristics and dietary habits. It is thought to be an unpleasant feature, especially because of its strong and masculine impression. Recently, the authors developed a method for the volumetric reduction of hypertrophied masseter muscles using radiofrequency energy to correct the squared facial appearance caused by the hypertrophy. This study was performed to investigate the effects of radiofrequency applied to reduce hypertrophied masseter muscles of patients who sought an aesthetic alternative for a slim, smooth, and feminine-looking lower facial contour. A total of 340 patients were treated. The patients usually recognized the volume change 3 to 6 weeks after treatment, and an objective volume reduction was observed within 3 months of the operation. The range of the reduction in the masseter thickness, as measured by ultrasonic examination at a 6-month postoperative follow-up visit, was 10% to 60% (mean, 27%). Most of the patients could eat a nearly normal diet after 4 weeks and were satisfied with the improved aesthetic contour lines of their lower face. Radiofrequency-induced coagulation tissue necrosis of the masseter did not cause any infections or limitations of mouth opening, and the clinical improvement was well maintained after the treatment.

  18. Long-term survival following radiofrequency ablation of colorectal liver metastases

    DEFF Research Database (Denmark)

    Babawale, Simeon Niyi; Jensen, Thomas Mandøe; Frøkjær, Jens Brøndum

    2015-01-01

    were evaluated, both before and after ablation therapies, with contrast enhanced computerised tomography and contrast enhanced ultrasonography. Histological evidence of malignant liver metastases was obtained in the few instances where contrast enhanced ultrasonography gave equivocal results. Accesses......AIM: To retrospectively evaluate the long-term survival of patients that received radiofrequency ablation (RFA) therapies of colorectal liver metastases. METHODS: In 2005 to 2008, RFA of 105 colorectal liver metastases (CRLM) were performed on 49 patients in our institution. The liver metastases...

  19. 21 CFR 886.4100 - Radiofrequency electrosurgical cautery apparatus.

    Science.gov (United States)

    2010-04-01

    ... bleeding by a high frequency electric current. (b) Classification. Class II. ... electrosurgical cautery apparatus. (a) Identification. A radiofrequency electrosurgical cautery apparatus is an AC...

  20. Temperature-Controlled Delivery of Radiofrequency Energy in Fecal Incontinence: A Randomized Sham-Controlled Clinical Trial.

    Science.gov (United States)

    Visscher, Arjan P; Lam, Tze J; Meurs-Szojda, Maria M; Felt-Bersma, Richelle J F

    2017-08-01

    Controlled delivery of radiofrequency energy has been suggested as treatment for fecal incontinence. The aim of this study was to determine whether the clinical response to the radiofrequency energy procedure is superior to sham in patients with fecal incontinence. This was a randomized sham-controlled clinical trial from 2008 to 2015. This study was conducted in an outpatient clinic. Forty patients with fecal incontinence in whom maximal conservative management had failed were randomly assigned to receiving either radiofrequency energy or sham procedure. Fecal incontinence was measured using the Vaizey incontinence score (range, 0-24). The impact of fecal incontinence on quality of life was measured by using the fecal incontinence quality-of-life score (range, 1-4). Measurements were performed at baseline and at 6 months. Anorectal function was evaluated using anal manometry and anorectal endosonography at baseline and at 3 months. At baseline, Vaizey incontinence score was 16.8 (SD 2.9). At t = 6 months, the radiofrequency energy group improved by 2.5 points on the Vaizey incontinence score compared with the sham group (13.2 (SD 3.1), 15.6 (SD 3.3), p = 0.02). The fecal incontinence quality-of-life score at t = 6 months was not statistically different. Anorectal function did not show any alteration. Patients with severe fecal incontinence were included in the study, thus making it difficult to generalize the results. Both radiofrequency energy and sham procedure improved the fecal incontinence score, the radiofrequency energy procedure more than sham. Although statistically significant, the clinical impact for most of the patients was negligible. Therefore, the radiofrequency energy procedure should not be recommended for patients with fecal incontinence until patient-related factors associated with treatment success are known. See Video Abstract at http://links.lww.com/DCR/A373.

  1. Evaluation of thermal and non-thermal effects of UHF RFID exposure on biological drugs.

    Science.gov (United States)

    Calcagnini, Giovanni; Censi, Federica; Maffia, Michele; Mainetti, Luca; Mattei, Eugenio; Patrono, Luigi; Urso, Emanuela

    2012-11-01

    The Radio Frequency Identification (RFID) technology promises to improve several processes in the healthcare scenario, especially those related to traceability of people and things. Unfortunately, there are still some barriers limiting the large-scale deployment of these innovative technologies in the healthcare field. Among these, the evaluation of potential thermal and non-thermal effects due to the exposure of biopharmaceutical products to electromagnetic fields is very challenging, but still slightly investigated. This paper aims to setup a controlled RF exposure environment, in order to reproduce a worst-case exposure of pharmaceutical products to the electromagnetic fields generated by the UHF RFID devices placed along the supply chain. Radiated powers several times higher than recommended by current normative limits were applied (10 W and 20 W). The electric field strength at the exposed sample location, used in tests, was as high as 100 V/m. Non-thermal effects were evaluated by chromatography techniques and in vitro assays. The results obtained for a particular case study, the ActrapidTM human insulin preparation, showed temperature increases lower than 0.5 °C and no significant changes in the structure and performance of the considered drug.

  2. Comparative analysis of toxicological evaluations for dermal exposure performed under two different EU regulatory frameworks.

    Science.gov (United States)

    Westerholm, Emma; Schenk, Linda

    2014-02-01

    Dermal exposure to chemicals is highly relevant in relation to the use of cosmetic products, both in consumers and in individuals exposed occupationally. Regulatory frameworks exist within the EU to limit the dermal exposure of the general population and workers to chemicals in general, as well as to limit the use of certain substances in cosmetic products. The objective of the study was to investigate and compare toxicological evaluations of dermal exposure performed under current regulatory frameworks. The publicly disseminated hazard information under the respective regulatory frameworks was compiled and compared for the five substances resorcinol, p-phenylenediamine, p-aminophenol, N-phenyl-p-phenylenediamine, and diethylene glycol monoethyl ether. A low consistency between evaluations was observed in respect to data coverage and cited dose descriptors. No systematic differences over all five substances were identified from the viewpoint of dermal hazard assessment. The critical effect and corresponding systemic effect dose descriptor was identical for two substances, differed somewhat for two other (a factor of 2-2.5). For N-phenyl-p-phenylenediamine a critical effect was only identified under REACH. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Evaluation of effective doses and population doses for computed tomography exposure in Taiwan

    International Nuclear Information System (INIS)

    Yeh, S.H.; Hsu, W.J.; Hsiao, H.S.

    2000-01-01

    As estimated, more than 80% of the man-made radiation dose is derived from medical applications, particularly from diagnostic treatment. Therefore, evaluating the radiation dose from diagnostic treatments is very important. The purpose of this study is to investigate the organ dose distribution and the effective doses from brain, chest and abdomen CT examinations. The organ equivalent dose and effective dose of patients were evaluated by exposing a male RANDO phantom to CT X-ray. Dose distributions in various organs were investigated using TLD LiF:Mg,Ti powder. A total of 224 TLDs were embedded in various organs of the phantom for each CT exposure. The organs that were monitored included bladder, bone marrow, breast, colon, liver, long, oesophagus, skin, stomach, thyroid and tests. The effective doses were calculated with reference to the tissue weighting factors recommended by the ICRP 60 report. Experimental TLDs were carefully calibrated using a secondary standard ionization chamber and a special X-ray machine, before they were exposed at hospitals. Taiwanese hospitals are classified as medical centers, area hospitals and local hospitals. This study investigated one hospital in each category. The experiments were performed according to the parameters (kVp, mAs) and procedures used in actual clinical examinations. In addition, this investigation also adopted the statistical mean and median parameters that obtained by a nationwide questionnaire methods in 1993 for it's CT X-ray exposure experiments. The organ doses significantly affected by the exposed region, i.e., brain, chest or abdomen. The effective doses were in the range of 0.93 to 2.41 mSv, 2.96 to 14.53 mSv and 4.55 to 12.30 mSv for brain, chest and abdomen exposure respectively. The investigated hospitals showed wide range of effective dose to the patients by the reasons of different CT machine, different exposure parameters (kVp, mAs) and different treatment procedures. This is the first time to

  4. Ochratoxin a contamination in italian wine samples and evaluation of the exposure in the italian population.

    Science.gov (United States)

    Brera, Carlo; Debegnach, Francesca; Minardi, Valentina; Prantera, Elisabetta; Pannunzi, Elena; Faleo, Silvia; de Santis, Barbara; Miraglia, Marina

    2008-11-26

    The scope of this study was to evaluate the exposure of the Italian population to ochratoxin A (OTA) attributable to wine consumption. With this aim 1166 wine samples (773 red wines, 290 white, 75 rose, and 28 dessert wines), collected in 19 different Italian regions and mostly produced between 1988 and 2004, were analyzed for OTA content. The obtained results are reported by year of harvest, geographical area of production, and type of wine. Red wine showed the highest maximum level of contamination (7.50 ng/mL), even though rose wines were characterized by a higher mean value (0.01 ng/mL). A gradually increasing mean concentration was also observed from the north (0.05 ng/mL) to south of Italy (0.54 ng/mL). Exposure calculations, performed using two different consumption databases, indicate a daily intake for consumer only of 0.59 up to 1.24 ng/(kg of b.w.)/day and of 0.33 up to 0.90 ng/(kg of b.w.)/day for the total population. Even in the worst case, corresponding to the calculation of the intake for consumers only in southern Italy and Islands and considering the mean consumption data increased by 1 standard deviation, a quite low exposure (1.68 ng/(kg of b.w.)/day, accounting for 9.8% of TDI) was obtained. Considering the overall OTA dietary exposure, obtained exposure rates indicate that wine did not pose a risk to the Italian population health.

  5. Utilization of Radium 226 from the oncology center - evaluation of staff exposure

    International Nuclear Information System (INIS)

    Andryskowski, G.

    2007-01-01

    226R a found application in oncological therapy due to its long half-life and the type of emitted radiation. After many years of application it was replaced by less radio toxic short-lived isotopes. In some oncology centres 226R a is still stored even though it is not used in therapy. The necessity of sealing it in glass, which is associated with long-lasting and direct exposure of a worker to radiation, is an indispensable condition if radium is to be collected by the Radioactive Waste Disposal Plant. The aim of the study is to present the problem of radium utilization on the basis of our own experience, which will make it easier to perform these activities in other oncology centers in Poland. After the initial analysis, it was calculated that a person working for 3 hours at a distance of 50 cm from 72 unprotected sources of radium 266 of total activity of 31 GBq would be exposed to a dose of 91.5 mSv. As this dose is about five times higher than the annual effective dose for category A workers, work in such conditions is strictly prohibited. After application of a lead shield, decrease of the dose (simultaneous exposure to the activity of only 5 sources) and the use of a hand-held gas burner enabling work behind the lead shield, a worker sealing radium in glass is exposed to a dose of 2 mSv. Estimation of the exposure was performed on the basis of individual and environmental dosimetry, measurement of radioactive contamination and dose rate. Mathematically calculated analysis of the hazard enabling determination of precise working conditions is a necessity which must be fulfilled before performing these activities. In the evaluation of hazard, not only external exposure was taken into account but also the possibility of external and internal exposure as well. Before starting work leakproofness of the sources was controlled. (author)

  6. Evaluation of Staff Radiation Exposure during Transthoracic Echocardiography Close to Myocardial Perfusion Imaging.

    Science.gov (United States)

    Massalha, Samia; Lugassi, Rachel; Raysberg, Elyahu; Koskosi, Amjad; Lechtenberg, Gerson; Israel, Ora; Kennedy, John A

    2018-04-03

    Transthoracic echocardiography (TTE) and myocardial perfusion imaging (MPI) are used in cardiac patients. In this study the radiation exposure of sonographers performing TTE following MPI was evaluated. Of 40 study patients, 30 underwent same-day 99m Tc sestamibi MPI and TTE, while another 10 underwent only TTE. Patients who underwent both studies were divided into three groups: right-handed TTE performed by an echocardiographer and right- and left-handed TTE performed by a cardiac sonographer. Seven thermoluminescent radiation dosimeter badges monitored the forehead, wrists, anterolateral right and left chest, sternal notch, and umbilical region of each examiner. Group characteristics were compared. Radiation exposures were deemed positive if >0.1 mSv. There were no statistical differences in patient weight and body mass index. The left-handed approach group had higher residual radioactivity (979 ± 73 vs 884 ± 73 MBq [P TTE, compared with the other two MPI groups. Radiation exposure was positive in the right anterolateral chest and hand (0.45 and 1 mSv, respectively) for the echocardiographer, the right anterolateral chest and wrist and umbilical region (0.59, 1.06, and 0.15 mSv, respectively) for the right-handed sonographer, and the left chest and hand (0.12 and 0.34 mSv, respectively) for the left-handed sonographer. Dosimeters indicated no radiation exposure in the TTE-only group. Staff members performing TTE after MPI are exposed to radiation that might warrant monitoring. Altering study sequence, adopting a left-handed approach, and using other radiation-reducing techniques can minimize the degree of exposure. Copyright © 2018 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

  7. Skin rejuvenation and wrinkle reduction using a fractional radiofrequency system.

    Science.gov (United States)

    Hruza, George; Taub, Amy Forman; Collier, Susannah L; Mulholland, Stephen Robert

    2009-03-01

    Skin resurfacing has evolved rapidly over the past 15 years from ablative techniques to nonablative methods and most recently fractional ablative resurfacing. The purposes of this study were to analyze the degree of tissue ablation, coagulation, and heating; and to evaluate the clinical efficacy and safety of a fractional radiofrequency (RF) device, for the treatment of wrinkles with fractional skin ablation and coagulation. Individuals scheduled for abdominoplasty received fractional RF treatment to the abdomen area, using different tips at varying energy densities and coverage rates. Biopsies were performed ex vivo following abdominoplasty and tissue samples were routinely processed and stained, using hematoxylin and eosin). Another group of subjects received 3 facial treatments, scheduled at 3 to 4 week intervals. Clinical improvement and response to therapy were evaluated with standardized photography and clinical assessment by the subjects and investigators. Histological findings immediately posttreatment revealed demarcated zones of ablation/coagulation/necrosis and subnecrosis up to a depth of 450 microm. Higher energy levels generated deeper effects. We noticed a tunable balance between ablation and coagulation/necrosis. These effects were coverage mode and energy density dependent. Subjects undergoing facial treatment had minimal pain, no permanent side effects, or significant downtime. Investigators' assessment for improvement in skin texture correlated with subjects' evaluation and was greater than 40% for approximately 50% of subjects. Eighty percent of the subjects were satisfied with the results. Higher energy levels and lower coverage rates produced better aesthetic results along with less pain. The clinical observations and histological findings suggest that fractionated ablative skin resurfacing using a fractional radiofrequency device resulted in a safe, tolerable and effective improvement in skin texture and reduction of wrinkles. The depth of

  8. An Evaluation of Potential Occupational Exposure to Asbestiform Amphiboles near a Former Vermiculite Mine

    Directory of Open Access Journals (Sweden)

    Julie F. Hart

    2009-01-01

    Full Text Available Amphibole asbestos (AA has been detected on the surface of tree bark in forests neighboring an abandoned vermiculite mine near Libby, Montana. In the present study, simulations were performed to assess potential AA exposure associated with United States Department of Agriculture Forest Service (FS occupational activities. Bark samples were collected prior, and personal breathing zone (PBZ and Tyvek clothing wipe samples were collected during and immediately after trials that simulated FS activities. Transmission electron microscopy (TEM analyses revealed AA bark concentrations up to 15 million structures per square centimeter (s/cm2. AA was detected in 25% of the PBZ TEM samples. AA was detected on wipe samples collected from all activities evaluated. This research demonstrates the potential for airborne exposure and transport of AA in the Kootenai National Forest. These findings are especially relevant to those that work in the area and to the general public who may conduct recreational activities.

  9. Evaluation of the diseases associated with occupational exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Frometa Suarez, I.

    1998-01-01

    Medical monitoring of workers occupationally exposed to ionizing radiation enables evaluation of their state of health, as well as early detection of general or somatic diseases which are considered as a criterion of unfitness for work, and which may or may not be related to the exposure conditions. A retrospective study is presented of all the cases of workers suspected to be suffering from radiation-related diseases which were referred for specialized study to the Institute of Occupational Medicine (IMT) during 1990-95. The incidence of the diseases and affected tissues is described, as well as the relationship between the time of manifestation and the type of source, the exposure time and the recorded dose levels. Diseases of the haemolymphopoietic system predominated, being observed in individuals exposed to medical radiodiagnostic sources. (author)

  10. Evaluating red-cockaded woodpeckers for exposure to West Nile Virus and blood parasites

    Science.gov (United States)

    Dusek, Robert J.; Richardson, D.; Egstad, Kristina F.; Heisey, Dennis M.

    2006-01-01

    A marked decline in the Picoides borealis (Red-cockaded Woodpecker [RCW]) population at Noxubee National Wildlife Refuge, MS, was observed in 2002. Demographic changes - including absence of hatch-year birds, decreases in size of known groups, and loss of known groups-were identified during annual fall surveys and are uncharacteristic of RCW populations. In 2003, a serosurvey of 28 adult RCWs was conducted to investigate the presence of West Nile virus (WNV) exposure in the population, possibly providing insight into whether WNV may have been responsible for this decline. Blood smears were also examined from these birds for blood parasites. We found no evidence of West Nile virus exposure or blood parasites in any of the RCWs sampled. Further monitoring of the RCW population and WNV activity in other species at Noxubee NWR is recommended to further evaluate the potential role of WNV and blood parasites in their decline.

  11. Temperature-controlled radiofrequency ablation of cardiac tissue: an in vitro study of the impact of electrode orientation, electrode tissue contact pressure and external convective cooling

    DEFF Research Database (Denmark)

    Petersen, H H; Chen, X; Pietersen, A

    1999-01-01

    A variety of basic factors such as electrode tip pressure, flow around the electrode and electrode orientation influence lesion size during radiofrequency ablation, but importantly is dependent on the chosen mode of ablation. However, only little information is available for the frequently used...... temperature-controlled mode. The purpose of the present experimental study was to evaluate the impact during temperature-controlled radiofrequency ablation of three basic factors regarding electrode-tissue contact and convective cooling on lesion size....

  12. Evaluation of air quality zone classification methods based on ambient air concentration exposure.

    Science.gov (United States)

    Freeman, Brian; McBean, Ed; Gharabaghi, Bahram; Thé, Jesse

    2017-05-01

    Air quality zones are used by regulatory authorities to implement ambient air standards in order to protect human health. Air quality measurements at discrete air monitoring stations are critical tools to determine whether an air quality zone complies with local air quality standards or is noncompliant. This study presents a novel approach for evaluation of air quality zone classification methods by breaking the concentration distribution of a pollutant measured at an air monitoring station into compliance and exceedance probability density functions (PDFs) and then using Monte Carlo analysis with the Central Limit Theorem to estimate long-term exposure. The purpose of this paper is to compare the risk associated with selecting one ambient air classification approach over another by testing the possible exposure an individual living within a zone may face. The chronic daily intake (CDI) is utilized to compare different pollutant exposures over the classification duration of 3 years between two classification methods. Historical data collected from air monitoring stations in Kuwait are used to build representative models of 1-hr NO 2 and 8-hr O 3 within a zone that meets the compliance requirements of each method. The first method, the "3 Strike" method, is a conservative approach based on a winner-take-all approach common with most compliance classification methods, while the second, the 99% Rule method, allows for more robust analyses and incorporates long-term trends. A Monte Carlo analysis is used to model the CDI for each pollutant and each method with the zone at a single station and with multiple stations. The model assumes that the zone is already in compliance with air quality standards over the 3 years under the different classification methodologies. The model shows that while the CDI of the two methods differs by 2.7% over the exposure period for the single station case, the large number of samples taken over the duration period impacts the sensitivity

  13. An evaluation of analytical methods, air sampling techniques, and airborne occupational exposure of metalworking fluids.

    Science.gov (United States)

    Verma, Dave K; Shaw, Don S; Shaw, M Lorraine; Julian, Jim A; McCollin, Shari-Ann; des Tombe, Karen

    2006-02-01

    This article summarizes an assessment of air sampling and analytical methods for both oil and water-based metalworking fluids (MWFs). Three hundred and seventy-four long-term area and personal airborne samples were collected at four plants using total (closed-face) aerosol samplers and thoracic samplers. A direct-reading device (DustTrak) was also used. The processes sampled include steel tube making, automotive component manufacturing, and small part manufacturing in a machine shop. The American Society for Testing and Materials (ASTM) Method PS42-97 of analysis was evaluated in the laboratory. This evaluation included sample recovery, determination of detection limits, and stability of samples during storage. Results of the laboratory validation showed (a) the sample recovery to be about 87%, (b) the detection limit to be 35 microg, and (c) sample stability during storage at room temperature to decline rapidly within a few days. To minimize sample loss, the samples should be stored in a freezer and analyzed within a week. The ASTM method should be the preferred method for assessing metalworking fluids (MWFs). The ratio of thoracic aerosol to total aerosol ranged from 0.6 to 0.7. A similar relationship was found between the thoracic extractable aerosol and total extractable aerosol. The DustTrak, with 10-microm sampling head, was useful in pinpointing the areas of potential exposure. MWF exposure at the four plants ranged from 0.04 to 3.84 mg/m3 with the geometric mean ranging between 0.22 to 0.59 mg/m3. Based on this data and the assumption of log normality, MWF exposures are expected to exceed the National Institute for Occupational Safety and Health recommended exposure limit of 0.5 mg/m3 as total mass and 0.4 mg/m3 as thoracic mass about 38% of the time. In addition to controlling airborne MWF exposure, full protection of workers would require the institution of programs for fluid management and dermal exposure prevention.

  14. A safety and feasibility study of a novel radiofrequency-assisted liposuction technique.

    Science.gov (United States)

    Blugerman, Guillermo; Schavelzon, Diego; Paul, Malcolm D

    2010-03-01

    The feasibility, safety, and efficacy of a novel radiofrequency device for radiofrequency-assisted liposuction were evaluated in various body areas. From July to December of 2008, 23 subjects underwent radiofrequency-assisted liposuction using the BodyTite system. Information regarding aesthetic results and local and systemic complications was collected immediately after the procedure and at 6- and 12-week follow-up. The mean age of the patients was 38.8 +/- 12.4 years, and 87 percent were women. Radiofrequency-assisted liposuction was performed successfully in all cases; volume aspirated per patient was 2404 +/- 1290 ml, whereas operative time was 158 +/- 44 minutes. All patients underwent liposuction at the hip and low abdominal areas, bilaterally. Body contour improvement was observed postoperatively in all patients and there were no severe systemic or local complications, although postoperative pain was minimal in all patients. Weight and circumference reductions were significant at both 6-week and 3-month follow-up. Skin tightening was judged optimal by the surgeon in all patients. The authors' study suggests that the removal of moderate volumes of fat with concurrent subdermal tissue contraction can be performed safely and effectively with radiofrequency-assisted liposuction. Additional benefits of this technique are excellent patient tolerance and fast recovery time. Nonetheless, a larger sample is required to confirm the authors' results and guarantee the efficacy and safety of the procedure. Direct comparison with traditional liposuction or energy-assisted liposuction techniques may provide some insights to tailor future indications of this novel technique.

  15. Characterization of radiofrequency field emissions from smart meters.

    Science.gov (United States)

    Tell, Richard A; Kavet, Robert; Mezei, Gabor

    2013-01-01

    This study presents measurement data that describe radiofrequency emission levels and patterns from smart meters (rated nominally at 1 W) currently deployed in Pacific Gas and Electric Company's service territory in northern California. The smart meters in our investigation could not be set to operate continuously and required a Field Service Unit to induce short periods of emitted fields. To obtain peak field data under both laboratory and ambient conditions, a spectrum analyzer scanned across the 83 transmitting channels between 902 and 928 MHz used by the smart meter on a random frequency-hopping basis. To obtain data describing temporal emission patterns, the analyzer operated in scope mode. Duty cycle was estimated using transmit data acquired by the system operator from over 88,000 m. Instantaneous peak fields at 0.3 m in front of the meters were no more than 15% of the US Federal Communications Commission (FCC) exposure limit for the general public, and 99.9% of the meters operated with a duty cycle of 1.12% or less during the sampling period. In a sample of measurements in six single-detached residences equipped with individual smart meters, no interior measurement of peak field exceeded 1% of the FCC's general public exposure limit.

  16. If time flies, are you more fun? The relative effect of expected exposure duration on the evaluation of social stimuli

    NARCIS (Netherlands)

    Vliek, M.L.W.; Rotteveel, M.

    2012-01-01

    Two studies investigated how expectancy violations of exposure duration affected preference for neutral faces. In two experiments, participants evaluated pictures of neutral faces, ostensibly exposed for the duration of 8 (Experiment 1) or 10 (Experiment 2) seconds each. Exposure duration was

  17. A comparison between pulsed radiofrequency and electro-acupuncture for relieving pain in patients with chronic low back pain.

    Science.gov (United States)

    Lin, Mu-Lien; Lin, Mu-Hung; Fen, Jun-Jeng; Lin, Wei-Tso; Lin, Chii-Wann; Chen, Po-Quang

    2010-01-01

    Many treatment options for chronic low back pain are available, including varied forms of electric stimulation. But little is known about the electricity effect between electro-acupuncture and pulsed radiofrequency. The objective of this study is to assess the difference in effectiveness of pain relief between pulsed radiofrequency and electro-acupuncture. Visual analog score (VAS) pain score, the Oswestry disability index (ODI) to measure a patient's permanent functional disability, and Short form 36 (SF-36) which is a survey used in health assessment to determine the cost-effectiveness of a health treatment, were used as rating systems to measure the pain relief and functional improvement effect of pulsed radiofrequency and electro-acupuncture, based on the methodological quality of the randomized controlled trials, the relevance between the study groups, and the consistency of the outcome evaluation. First, the baseline status before therapy shows no age and gender influence in the SF-36 and VAS score but it is significant in the ODI questionnaire. From ANOVA analyses, it is apparent that radiofrequency therapy is a significant improvement over electro-acupuncture therapy after one month. But electro-acupuncture also showed functional improvement in the lumbar spine from the ODI. This study provides sufficient evidence of the superiority of pulsed radiofrequency (PRF) therapy for low back pain relief compared with both electro-acupuncture (EA) therapy and the control group. But the functional improvement of the lumbar spine was proved under EA therapy only. Both therapies are related to electricity effects.

  18. TREATMENT OF LUMBAR HERNIAS BY ENDOSCOPIC NUCLEOPLASTY WITH RADIOFREQUENCY

    Directory of Open Access Journals (Sweden)

    Heber Humberto Alfaro Pachicano

    2016-03-01

    Full Text Available ABSTRACT Objective: To evaluate the postoperative outcomes of minimally invasive technique for treating lumbar disc herniation in patients undergoing percutaneous endoscopic nucleoplasty with radiofrequency in the center of minimally invasive procedures Veracruz (CEMIVER of the HRAEV.. Methods: A descriptive, comparative, ambispective and longitudinal study. The clinical records of patients who underwent herniated disc surgery were reviewed from March 2010 to March 2015. Inclusion criteria were individuals of both sexes, aged 18-65 years, with disc herniation diagnosis by MRI, evocative discography (pain and clinical evaluation. The variables were analyzed by VAS, Oswestry disability index for functional assessment and Macnab criteria for modified retrospective cross clinical classification. Results: 161 patients were included, 81 female and 80 male, aged between 18 and 65 years with severe (83.8% and moderate (16.2% disability according to the Oswestry disability index; the total of excellent results was 83.8%, 9.5% were good, 4.8% were median and 1.9% were poor results, according to the Macnab criteria; the average time of surgery was 84 minutes per procedure, and the postoperative average bleeding was 65 ml. Of the total, 87.4% of the patients were on an outpatient basis and 7.6% had a short hospital stay.. Conclusion: It was found that percutaneous endoscopic nucleoplasty with radiofrequency technique is a procedure that offers great benefits for patients with lumbar disc herniation, including performing it under local anesthesia, with clear visualization of the surgical field, minimal pain, little bleeding, shorter operative time, does not cause instability of anatomical structures and has minimal rate of complications.

  19. Predictors of Luminal Loss in Pulmonary Veins After Radiofrequency Ablation.

    Science.gov (United States)

    Martín-Garre, Susana; Pérez-Castellano, Nicasio; Quintanilla, Jorge G; Ferreiros, Joaquín; Pérez-Villacastín, Julián

    2015-12-01

    The reported incidences of stenosis after radiofrequency ablation of pulmonary veins are highly variable. Moreover, most studies have focused on severe stenosis and have overlooked mild stenosis. Our aims were to study postablation morphological changes in the pulmonary veins and to evaluate preablation magnetic resonance imaging predictors for stenosis. Eighty consecutive patients with atrial fibrillation underwent cardiac magnetic resonance imaging before undergoing radiofrequency ablation. Magnetic resonance imaging was repeated a median of 95 days after ablation. Ostium area/ellipticity and atrial volume were blindly assessed. We evaluated the presence of stenosis and classified it as mild ( 70%). Postablation stenosis was identified in 78 of 322 veins (24.2%). The stenosis was mild in 66 (84.6%), moderate in 11 (14.1%), and severe in 1 (1.3%). All of them were asymptomatic. The left inferior pulmonary vein showed the highest frequency of stenosis, which was detected in 26% of them (P < .001). A multiple regression analysis revealed that left inferior pulmonary vein (odds ratio = 3.089; P = .02) and a greater preablation ostium area (odds ratio = 1.009; P < .001) were independent predictors for postablation stenosis. Age (odds ratio = 1.033) showed a strong trend to statistical significance (P = .06). After ablation, vein ostia size is reduced and stenosis is detected in less than one third of patients. Most cases are mild, and severe stenosis is rare. Postablation stenosis is more likely to develop in older patients, those with larger vein ostia, and in the left inferior pulmonary veins. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  20. Survival after Radiofrequency Ablation for 100 Cases of Lung Neoplasms

    Directory of Open Access Journals (Sweden)

    Baodong LIU

    2011-04-01

    Full Text Available Background and objective Surgical resection is the preferred treatment in selected patients with pulmonary neoplasms. In older than 70 years or have compromised cardiopulmonary status or coexistent medical problems patients, radiofrequency ablation (RFA may offer an alternative option. The aim of this study is to evaluate the therapeutic effects after RFA in 100 patients with pulmonary neoplasms. Methods One handred cases of unresectable lung tumors with 106 lesions were underwent RFA therapy. To evaluate the therapeutic effect and complications of lung tumors using spiral CT scanning and SPECT in 1-3 months after RFA. Results One hundred patients underwent RFA for lung neoplasms (62 men, 38 women; median age, 66.6 years; range, 36 to 91 years. Eighty-six patients with primary lung neoplasms and 14 patients with pulmonary metastases underwent RFA. Treatment was complete in all cases, no treatment-related deaths occurred in all of the 100 patients and serious morbidity associated with the procedures. The median overall survival for the entire group of patients was 13.0 months, the one and two years overall survival for total of were 51% and 32.5% respectively. No differences in overall survival noted between patients with primary and metastases lung neoplasms (P=0.922. The median overall survival for the early stage of patients was 28.0 months, 2-year overall survival for early stage primary lung cancer patients were 57.7%. Conclusion RFA is a safe and effective procedure in selective lung tumors. CT-guided radiofrequency ablation is a minimally invasive treatment option. RFA could act as an alternative treatment to inoperable lung cancer.

  1. Stereotactic Radiofrequency Ablation for Metastatic Melanoma to the Liver

    Energy Technology Data Exchange (ETDEWEB)

    Bale, Reto, E-mail: reto.bale@i-med.ac.at; Schullian, Peter [Medical University Innsbruck, Department of Radiology, Section of Interventional Oncology - Microinvasive Therapy (SIP) (Austria); Schmuth, Matthias [Medical University Innsbruck, Department of Dermatology (Austria); Widmann, Gerlig; Jaschke, Werner [Medical University Innsbruck, Department of Radiology, Section of Interventional Oncology - Microinvasive Therapy (SIP) (Austria); Weinlich, Georg [Medical University Innsbruck, Department of Dermatology (Austria)

    2016-08-15

    PurposeTo evaluate the outcome of patients with melanoma liver metastasis treated with stereotactic radiofrequency ablation (SRFA).Material and MethodFollowing IRB approval, a retrospective evaluation of the treatment of 20 patients with 75 melanoma liver metastases was performed.ResultsA median number of 2 lesions (range 1–14) per patient with a median size of 1.7 cm (range 0.5–14.5 cm) were treated. 67 lesions were <3 cm (89.3 %) and 8 lesions were >3 cm (10.7 %). Per patient a median of 1 ablation session was performed (range: 1–4) totaling 34 sessions. There were no procedure-related deaths and all major complications (n = 3) could be easily treated by pleural drainages. The primary and secondary success rates were 89.3 and 93.3 %, respectively. The overall local recurrence rate was 13.3 %. Four of ten local recurrences were re-treated successfully by SRFA. During follow-up, 9/20 patients developed extrahepatic metastatic disease and 10/20 had liver recurrence at any location. The median OS from the date of SRFA was 19.3 months, with an OS of 64, 41, and 17 % at 1, 3, and 5 years, with no significant difference for patients with cutaneous and ocular melanoma. The median DFS after SRFA for all 20 patients was 9.5 months, with 37, 9, and 0 % at 1, 3, and 5 years.ConclusionsDue to the high local curative potential and the promising long-term survival rates associated with minimal morbidity and mortality, radiofrequency ablation seems to be an attractive alternative to resection in patients with melanoma liver metastases.

  2. Exposure dose evaluation of worker at radioactive waste incineration facility on KAERI

    International Nuclear Information System (INIS)

    Park, Sang Kyu; Jeon, Jong Seon; Kim, Youn Hwa; Lee, Jae Min; Lee, Gi Won

    2011-01-01

    An incineration treatment of inflammable radioactive wastes leads to have a reduction effect of disposal cost and also to contribute an enhancement of safety at a disposal site by taking the advantage of stabilization of the wastes which is accomplished by converting organic materials into inorganic materials. As it was required for an incineration technology, KAERI (Korea Atomic Energy Research Institute) has developed a pilot incineration process and then constructed a demonstration incineration facility having based on the operating experiences of the pilot process. In this study, worker exposure doses were evaluated to confirm safety of workers before the demonstration incineration facility will commence a commercial. (author)

  3. Evaluation of AirGIS: a GIS-based air pollution and human exposure modelling system

    DEFF Research Database (Denmark)

    Ketzel, Matthias; Berkowicz, Ruwim; Hvidberg, Martin

    2011-01-01

    shows, in general, a good performance for both long-term averages (annual and monthly averages), short-term averages (hourly and daily) as well as when reproducing spatial variation in air pollution concentrations. Some shortcomings and future perspectives of the system are discussed too.......This study describes in brief the latest extensions of the Danish Geographic Information System (GIS)-based air pollution and human exposure modelling system (AirGIS), which has been developed in Denmark since 2001 and gives results of an evaluation with measured air pollution data. The system...

  4. The effect of 1800MHz radio-frequency radiation on NMDA receptor subunit NR1 expression and peroxidation in the rat brain in healthy and inflammatory states.

    Science.gov (United States)

    Bodera, Paweł; Makarova, Katerina; Zawada, Katarzyna; Antkowiak, Bożena; Paluch, Małgorzata; Sobiczewska, Elżbieta; Sirav, Bahriye; Siwicki, Andrzej K; Stankiewicz, Wanda

    2017-08-01

    The aim of this study was to evaluate the effect of repeated exposure (5 times for 15min) of 1800MHz radio-frequency radiation (RFR) on N-methyl-d-aspartate receptor subunit NR1 (NMDA-NR1) expression in the brains of rats in a persistent inflammatory state. We also measured the effect of RFR combined with tramadol (TRAM) to determine the potential antioxidant capacity of this agent. The effects of the Global System for Mobile Communication (GSM) modulated 1800MHz RFR exposure on the expression and activity of glutamate receptor channels with antioxidative activity in brain tissue was measured using oxygen radical absorbance capacity (ORAC) and electron spin resonance (ESR) detection of the hydroxyl radical generated by the Fenton reaction. NMDA-NR1 was measured in the cerebral tissue of rats with inflammation (complete Freund's adjuvent) and those injected with tramadol after RFR exposure (RFR, RFR/TRAM) and in non-exposed (baseline, TRAM) rats. No differences between the baseline group and the exposed group (RFR) were observed. NMDA-NR1 expression decreased after CFA injection and RFR exposure, and an elevated expression of NMDA-NR1 was observed in healthy control rats of both groups: TRAM/RFR and RFR. ORAC assessment revealed a robust effect of RFR, however the other experiments revealed equivocal effects. Further studies examining the combination of ORAC with NMDA are warranted to elucidate more clearly the effect of RFR on the brain. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  5. Evaluation of local density enhancement of microcapsules in artificial blood vessel during exposure to focused ultrasound

    Science.gov (United States)

    Nakamoto, Ryusuke; Masuda, Kohji; Watarai, Nobuyuki; Taguchi, Yuto; Kato, Toshikazu; Yoshinaga, Takashi; Miyamoto, Yoshitaka; Chiba, Toshio

    2011-09-01

    We have proposed a physical DDS (Drug Delivery System) which makes use of microcapsules of μm size, which may contain a specified drug and also are easily affected by ultrasound exposure near their resonant frequency, to release various kinds of medications. These capsules are easily detected and actuated by ultrasound. However, because of the diffusion of capsules after injection into human body, it was difficult to enhance the efficiency of drug delivery. Thus we have considered a method for controlling the density of capsules in flow which uses acoustic radiation force, which moves the capsules to balance flow resistance. We have experimented with trapping microcapsules or microbubbles in flow of an artificial blood vessel. We have evaluated the effect of radiation force by measuring the trapped area of capsules or bubbles for various frequencies, sound pressures, and exposure times of sinusoidal ultrasound. The trapped area of capsules or bubbles increased with sound pressure and exposure time, and decreased with frequency. From those results, we have derived optimal conditions for trapping the capsules or bubbles.

  6. Evaluation of occupation hot exposure in industrial workplaces in a subtropical country

    Directory of Open Access Journals (Sweden)

    Ming-Chi Wei

    2017-06-01

    Full Text Available Objectives: The objective of this study has been to evaluate the occupational heat exposure of 12 workers at 5 plants in a subtropical country. Material and Methods: The heat stresses and strain on workers in 5 plants were assessed by the International Organization for Standardization (ISO 7243 index (wet bulb globe temperature – WBGT and the ISO 7933 index (maximum allowable exposure time – Dlim. Results: Results indicated that 42% of the subjects (5 workers surpassed the WBGT limits. According to the Dlim, 42% of the subjects could not continue working in the hot environments. The relationships between the various heat stress indices and the WBGT index were also correlated. However, further studies from different heat environments and more subjects should be performed. Conclusions: The sensitive dependence of skin temperature on meteorological and physiological indices for each subject was clearly observed. Obviously, the heart rate response to metabolic rate was much greater than that caused by environmental heat alone. The exponential relationship between workers’ duration-limited exposure time, predicted by various estimated criteria, and WBGT were also found. Int J Occup Med Environ Health 2017;30(3:379–395

  7. Evaluation of occupation hot exposure in industrial workplaces in a subtropical country.

    Science.gov (United States)

    Yang, Yu-Chiao; Wei, Ming-Chi; Hong, Show-Jen

    2017-05-08

    The objective of this study has been to evaluate the occupational heat exposure of 12 workers at 5 plants in a subtropical country. The heat stresses and strain on workers in 5 plants were assessed by the International Organization for Standardization (ISO) 7243 index (wet bulb globe temperature - WBGT) and the ISO 7933 index (maximum allowable exposure time - Dlim). Results indicated that 42% of the subjects (5 workers) surpassed the WBGT limits. According to the Dlim, 42% of the subjects could not continue working in the hot environments. The relationships between the various heat stress indices and the WBGT index were also correlated. However, further studies from different heat environments and more subjects should be performed. The sensitive dependence of skin temperature on meteorological and physiological indices for each subject was clearly observed. Obviously, the heart rate response to metabolic rate was much greater than that caused by environmental heat alone. The exponential relationship between workers' duration-limited exposure time, predicted by various estimated criteria, and WBGT were also found. Int J Occup Med Environ Health 2017;30(3):379-395. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  8. [Analysis of phthalates in aromatic and deodorant aerosol products and evaluation of exposure risk].

    Science.gov (United States)

    Sato, Yoshiki; Sugaya, Naeko; Nakagawa, Tomoo; Morita, Masatoshi

    2015-01-01

    We established an analytical method for the detection of seven phthalates, dimethyl phthalate, diethyl phthalate (DEP), benzyl butyl phthalate, di-i-butyl phthalate, dibutyl phthalate (DBP), diethylhexyl phthalate (DEHP), and di-n-octhyl phthalate, using an ultra high performance liquid chromatograph equipped with a photodiode array detector. This method is quick, with minimal contamination, and was applied to the analysis of aromatic and deodorant aerosol products. Phthalates were detected in 15 of 52 samples purchased from 1999 to 2012 in Yokohama. Three types of phthalate (DEP, DBP, DEHP) were detected, and their concentrations ranged from 0.0085-0.23% DEP in nine samples, 0.012-0.045% DBP in four samples, and 0.012-0.033% DEHP in four samples. No other phthalate esters were detected. Furthermore, we estimated phthalate exposure via breathing in commonly used aromatic and deodorant aerosol products, then evaluated the associated risk. The estimated levels of phthalate exposure were lower than the tolerated daily limit, but the results indicated that aromatic and deodorant aerosol products could be a significant source of phthalate exposure.

  9. Investigation of human exposure to triclocarban after showering, and preliminary evaluation of its biological effects

    Science.gov (United States)

    Schebb, Nils Helge; Inceoglu, Bora; Ahn, Ki Chang; Morisseau, Christophe; Gee, Shirley; Hammock, Bruce D.

    2012-01-01

    The antibacterial soap additive triclocarban (TCC) is widely used in personal care products. TCC has a high environmental persistence. We developed and validated a sensitive online solid phase extraction-LC-MS/MS method to rapidly analyze TCC and its major metabolites in urine and other biological samples to assess human exposure. We measured human urine concentrations 0–72 h after showering with a commercial bar soap containing 0.6% TCC. The major route of renal elimination was excretion as N-glucuronides. The absorption was estimated at 0.6% of the 70±15 mg TCC in the soap used. The TCC N-glucuronide urine concentration varied widely among the subjects and continuous daily use of the soap led to steady state levels of excretion. In order to assess potential biological effects arising from this exposure we screened TCC for the inhibition of human enzymes in vitro. We demonstrate that TCC is a potent inhibitor of the enzyme soluble epoxide hydrolase (sEH), whereas TCC′s major metabolites lack strong inhibitory activity. Topical administration of TCC at similar levels to rats in a preliminary in vivo study however failed to alter plasma biomarkers of sEH activity. Overall the analytical strategy described here revealed that use of TCC soap causes exposure levels that warrant further evaluation. PMID:21381656

  10. Development of ECOREA-II code for the evaluation of exposures from radionuclides through food Chain

    International Nuclear Information System (INIS)

    Yu, Dong Han; Lee, Han Soo

    2002-01-01

    The release of radionuclides from nuclear facilities following an accident into air results in human exposures by intakes of plant products such as rice, vegetables and/or animal products including meat, milk and eggs from contaminated soil. In order to evaluate such exposures from radioactive substances, it is essential to mathematically predict the behavior of these substances in the environments. A computer code, named 'ECOREA-II' is developing to assess human exposures through food chain of such substances in Korea. ECOREA-II code has a dynamic compartment-based model at its core, the graphical user interface (GUI) for the selection of input parameters and result displays on personal computers, and generation of data files for a GIS (Graphical Information System). Even the code is developed mostly based currently available models and/or codes, a new model is included for the time-dependent growth dilution in a vegetation part. Effort on The development of the code is towards the prediction of the behavior and pattern of radionuclides in a specific food chain condition in Korea. Finally, it provides a more user-friendly environment such as GUI developed based on the VBA(Visual Basic Application) for personal users. Therefore, the current code, when more fully developed, is expected to increase the understanding of environmental safety assessment of nuclear facilities following an accident and provide a reasonable regulatory guideline with respect to food safety issues

  11. Evaluation of hepatitis A vaccine in post-exposure prophylaxis, The Netherlands, 2004-2012.

    Directory of Open Access Journals (Sweden)

    Jane Whelan

    Full Text Available BACKGROUND: The secondary attack rate of hepatitis A virus (HAV among contacts of cases is up to 50%. Historically, contacts were offered immunoglobulin (IG, a human derived blood product as post-exposure prophylaxis (PEP. Amid safety concerns about IG, HAV vaccine is increasingly recommended instead. Public health authorities' recommendations differ, particularly for healthy contacts ≥40 years old, where vaccine efficacy data is limited. We evaluated routine use of HAV vaccine as an alternative to immunoglobulin in PEP, in those considered at low risk of severe infection in the Netherlands. METHODS: Household contacts of acute HAV cases notified in Amsterdam (2004-2012 were invited ≤14 days post-exposure, for baseline anti-HAV testing and PEP according to national guidelines: immunoglobulin if at risk of severe infection, or hepatitis A vaccine if healthy and at low risk (aged 40 years of age. In healthy contacts vaccinated per-protocol ≤8 days post-exposure, RR(ref. ≤15 years of secondary infection in those >40 years was 12.0 (95%CI:1.3-106.7. CONCLUSIONS: Timely administration of HAV vaccine in PEP was feasible and the secondary attack rate was low in those 40 years of age and those vulnerable to severe disease.

  12. Evaluation of Toluene Exposure in Workers at Industrial Area of Sidoarjo, Indonesia by Measurement of Urinary Hippuric Acid

    Directory of Open Access Journals (Sweden)

    Moch Sahri

    2013-12-01

    How to cite this article: Sahri M, Widajati N. Evaluation of Toluene Exposure in Workers at Industrial Area of Sidoarjo, Indonesia by Measurement of Urinary Hippuric Acid. Asia Pac J Med Toxicol 2013;2:145-9.

  13. High Throughput PBPK: Evaluating EPA's Open-Source Data and Tools for Dosimetry and Exposure Reconstruction (SOT)

    Science.gov (United States)

    To address this need, new tools have been created for characterizing, simulating, and evaluating chemical biokinetics. Physiologically-based pharmacokinetic (PBPK) models provide estimates of chemical exposures that produce potentially hazardous tissue concentrations, while tissu...

  14. Evaluation of urinary cyclohexanediols and cyclohexanol as biomarkers of occupational exposure to cyclohexane.

    Science.gov (United States)

    Takeuchi, Akito; Ogawa, Yoshihiro; Endo, Yoko; Kawai, Toshio; Namera, Akira; Yamamuro, Kenji; Sumino, Kimiaki; Endo, Ginji

    2015-01-01

    The aim of the present study was to comparatively evaluate the usefulness of urinary cyclohexanediols (CHdiols-U) and cyclohexanol (CHol-U) as biomarkers of occupational exposure to cyclohexane (CH). Sixteen subjects (14 men and 2 women) were exposed to CH during proof-printing work. Personal exposure monitoring was conducted during the whole shift on the last working day of the week. The time-weighted average level of exposure to CH (CH-A) was measured using a diffusive sampler. Two urine samples were collected from each worker at different times during the same week: a baseline urine sample (before the first shift of the working week, after a 5-day holiday with no CH exposure) and an end-of-shift urine sample (after the last shift of the same working week, the same day personal exposure monitoring was conducted). CH-A, CHdiols-U and CHol-U were determined using a gas chromatograph-flame ionization detector. The CH-A concentrations ranged from 4.5 to 60.3 ppm, with a geometric mean (GM) of 18.1 ppm. The GMs and ranges (in parenthesis) of the creatinine (cr)-corrected end-of-shift 1,2-CHdiol-U, 1,4-CHdiol-U and CHol-U concentrations were 12.1 (4.1-36.6), 7.5 (2.4-20.1) and 0.4 (0.2-1.0) mg/g cr, respectively. Both CHdiols-U at the end of the shift were significantly correlated with CH-A (correlation coefficients for 1,2-CHdiol-U and 1,4-CHdiol-U of 0.852 and 0.847, respectively). No correlation was observed between CH-A and CHol-U. CHdiols-U at the end of the last shift of the working week are suitable biomarkers of occupational exposure to CH, but CHol-U is not suitable.

  15. An evaluation of retrofit engineering control interventions to reduce perchloroethylene exposures in commercial dry-cleaning shops.

    Science.gov (United States)

    Earnest, G Scott; Ewers, Lynda M; Ruder, Avima M; Petersen, Martin R; Kovein, Ronald J

    2002-02-01

    Real-time monitoring was used to evaluate the ability of engineering control devices retrofitted on two existing dry-cleaning machines to reduce worker exposures to perchloroethylene. In one dry-cleaning shop, a refrigerated condenser was installed on a machine that had a water-cooled condenser to reduce the air temperature, improve vapor recovery, and lower exposures. In a second shop, a carbon adsorber was retrofitted on a machine to adsorb residual perchloroethylene not collected by the existing refrigerated condenser to improve vapor recovery and reduce exposures. Both controls were successful at reducing the perchloroethylene exposures of the dry-cleaning machine operator. Real-time monitoring was performed to evaluate how the engineering controls affected exposures during loading and unloading the dry-cleaning machine, a task generally considered to account for the highest exposures. The real-time monitoring showed that dramatic reductions occurred in exposures during loading and unloading of the dry-cleaning machine due to the engineering controls. Peak operator exposures during loading and unloading were reduced by 60 percent in the shop that had a refrigerated condenser installed on the dry-cleaning machine and 92 percent in the shop that had a carbon adsorber installed. Although loading and unloading exposures were dramatically reduced, drops in full-shift time-weighted average (TWA) exposures were less dramatic. TWA exposures to perchloroethylene, as measured by conventional air sampling, showed smaller reductions in operator exposures of 28 percent or less. Differences between exposure results from real-time and conventional air sampling very likely resulted from other uncontrolled sources of exposure, differences in shop general ventilation before and after the control was installed, relatively small sample sizes, and experimental variability inherent in field research. Although there were some difficulties and complications with installation and

  16. Radiofrequency ablation as initial therapy in paroxysmal atrial fibrillation

    DEFF Research Database (Denmark)

    Cosedis Nielsen, Jens; Johannessen, Arne; Raatikainen, Pekka

    2012-01-01

    There are limited data comparing radiofrequency catheter ablation with antiarrhythmic drug therapy as first-line treatment in patients with paroxysmal atrial fibrillation.......There are limited data comparing radiofrequency catheter ablation with antiarrhythmic drug therapy as first-line treatment in patients with paroxysmal atrial fibrillation....

  17. Endoscopic ultrasound-guided radiofrequency ablation of the pancreas

    DEFF Research Database (Denmark)

    Silviu, Ungureanu Bogdan; Daniel, Pirici; Claudiu, Mărgăritescu

    2015-01-01

    ultrasound (EUS)-guided radiofrequency ablation (RFA) probe through a 19G needle in order to achieve a desirable necrosis area in the pancreas. Radiofrequency ablation of the head of the pancreas was performed on 10 Yorkshire pigs with a weight between 25 kg and 35 kg and a length of 40-70 cm. Using an EUS...

  18. 77 FR 43535 - Grantee Codes for Certified Radiofrequency Equipment

    Science.gov (United States)

    2012-07-25

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 2 Grantee Codes for Certified Radiofrequency Equipment AGENCY: Federal Communications... radiofrequency (RF) devices under part 2 of its rules. This program is one of the primary means that the...

  19. 21 CFR 882.4400 - Radiofrequency lesion generator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiofrequency lesion generator. 882.4400 Section 882.4400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... lesion generator. (a) Identification. A radiofrequency lesion generator is a device used to produce...

  20. Evaluation of pyrethroid exposures in pregnant women from 10 Caribbean countries.

    Science.gov (United States)

    Dewailly, Eric; Forde, Martin; Robertson, Lyndon; Kaddar, Nisrin; Laouan Sidi, Elhadji A; Côté, Suzanne; Gaudreau, Eric; Drescher, Olivia; Ayotte, Pierre

    2014-02-01

    Pyrethroid pesticides are commonly used in tropical regions such as the Caribbean as household insecticides, pet sprays, and where malaria is endemic, impregnated into mosquito-repellent nets. Of particular concern is exposure during pregnancy, as these compounds have the potential to cross the placental barrier and interfere with fetal development, as was shown in limited animal studies. The objective of this study was to evaluate exposure to pyrethroids to pregnant women residing in 10 English-speaking Caribbean countries. Pyrethroid exposures were determined by analyzing five pyrethroid metabolites in urine samples from 295 pregnant women: cis-DBCA, cis-DCCA, trans-DCCA, 3-PBA, and 4-F-3-PBA. Pyrethroid metabolite concentrations in Caribbean pregnant women were generally higher in the 10 Caribbean countries than levels reported for Canadian and U.S. women. In Antigua & Barbuda and Jamaica participants the geometric mean concentrations of cis-DBCA was significantly higher than in the other nine countries together (p<0.0001 and <0.0012 respectively). For cis- and trans-DCCA, only Antigua & Barbuda women differed significantly from participants of the other nine Caribbean countries (p<0.0001). Urinary 4-F-3-PBA and 3-PBA levels were significantly higher in Antigua & Barbuda (p<0.0028 and p<0.0001 respectively) as well as in Grenada (p<0.0001 and p<0.007 respectively). These results indicate extensive use of pyrethroid compounds such as permethrin and cypermethrin in Caribbean households. In Antigua & Barbuda, the data reveals a greater use of deltamethrin. This study underscores the need for Caribbean public health authorities to encourage their populations, and in particular pregnant women, to utilize this class of pesticides more judiciously given the potentially adverse effects of exposure on fetuses and infants. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Weight-of-evidence evaluation of long-term ozone exposure and cardiovascular effects.

    Science.gov (United States)

    Prueitt, Robyn L; Lynch, Heather N; Zu, Ke; Sax, Sonja N; Venditti, Ferdinand J; Goodman, Julie E

    2014-10-01

    We conducted a weight-of-evidence (WoE) analysis to assess whether the current body of research supports a causal relationship between long-term ozone exposure (defined by EPA as at least 30 days in duration) at ambient levels and cardiovascular (CV) effects. We used a novel WoE framework based on the United States Environmental Protection Agency's National Ambient Air Quality Standards causal framework for this analysis. Specifically, we critically evaluated and integrated the relevant epidemiology and experimental animal data and classified a causal determination based on categories proposed by the Institute of Medicine's 2008 report, Improving the Presumptive Disability Decision-making Process for Veterans. We found that the risks of CV effects are largely null across human and experimental animal studies. The few positive associations reported in studies of CV morbidity and mortality are very small in magnitude, mainly reported in single-pollutant models, and likely attributable to bias, chance, or confounding. The few positive effects in experimental animal studies were observed mainly in ex vivo studies at high exposures, and even the in vivo findings are not likely relevant to humans. The available data also do not support a biologically plausible mechanism for the effects of ozone on the CV system. Overall, the current WoE provides no convincing case for a causal relationship between long-term exposure to ambient ozone and adverse effects on the CV system in humans, but the limitations of the available studies preclude definitive conclusions regarding a lack of causation; thus, we categorize the strength of evidence for a causal relationship between long-term exposure to ozone and CV effects as "below equipoise."

  2. Evaluating acute effects of potential reduced-exposure products for smokers: clinical laboratory methodology.

    Science.gov (United States)

    Breland, Alison B; Buchhalter, August R; Evans, Sarah E; Eissenberg, Thomas

    2002-01-01

    Harm reduction for tobacco smokers may involve reducing their exposure to lethal smoke constituents. Assessing smoke constituent exposure and any resulting harm reduction from a potential reduced-exposure product (PREP) will involve preclinical, clinical, and epidemiological research. The purpose of this study was to evaluate a clinical laboratory model for assessing the acute effects of PREPs for smokers. Philip Morris' Accord and R.J. Reynolds' Eclipse were used as examples. Twenty overnight-abstinent smokers (> 15 'light' or 'ultra-light' cigarettes/day) participated in 4 Latin-square ordered, 2.5-hr sessions in which they completed an 8-puff smoking bout every 30 minutes. Sessions were separated by at least 24 hours and differed by product used: own brand, denicotinized tobacco cigarettes, Accord, or Eclipse. Tobacco withdrawal and carbon monoxide (CO) were assessed before and after smoking, heart rate was assessed before and during smoking, and puff volume, duration, and interpuff interval were assessed while subjects smoked. Blood was sampled at the beginning and end of each session. Relative to normal cigarettes, Accord was less effective at suppressing withdrawal and produced minimal CO boost despite the fact that, when using Accord, subjects took bigger and longer puffs. Eclipse suppressed withdrawal fully and increased CO boost by approximately 30%. Own brand, Accord, and Eclipse, but not denicotinized cigarettes, increased plasma nicotine concentration. Taken together, these results suggest that neither Accord nor Eclipse is likely to be an effective reduced-exposure product for smokers and that this clinical laboratory model is valuable.

  3. Post-pregnancy body contouring using a combined radiofrequency, infrared light and tissue manipulation device.

    Science.gov (United States)

    Winter, Marc L

    2009-12-01

    Non-invasive body contouring is an increasingly popular aesthetic application. Previous data support the efficacy of combined radiofrequency, infrared and skin manipulation for cellulite treatment. To evaluate the performance of a high-power device (50 W as opposed to 25 W) combining these energies for reshaping and improvement of skin texture/laxity in postpartum women. Twenty women received five weekly treatments to the abdomen, buttocks and thighs with the VelaShape system. We followed up each patient's weight and nutritional habits. Outcome was assessed using reproducible circumference measurements, digital photography, the physician's scores of cellulite and improvement as well as patient satisfaction. Safety was evaluated by recording subjects' comfort and tolerance. The overall mean circumferences reduction was 5.4 +/- 0.7 cm (p radiofrequency, infrared and mechanical manipulation.

  4. Radiofrequency: an update on latest innovations.

    Science.gov (United States)

    Sadick, Neil S; Malerich, Sarah A; Nassar, Amer H; Dorizas, Andrew S

    2014-11-01

    As the aging population in our society continues to grow, new technologies and procedures promising a more youthful appearance are continuously sought. The utilization of radiofrequency technology remains a novel method for the treatment of many aesthetic and medical dermatological indications. Innovative applications are constantly identified, expanding treatment options for various patient concerns including aging of the hands, cellulite, non-invasive lipolysis, and postpartum skin laxity. Non-invasive treatments are ideal for busy patients seeking minimal recovery time and so called lunch-time procedures. Furthermore, new developments in treatment devices enhance efficacy while decreasing patient discomfort.

  5. A new exposure model to evaluate smoked illicit drugs in rodents: A study of crack cocaine.

    Science.gov (United States)

    Hueza, Isis M; Ponce, Fernando; Garcia, Raphael C T; Marcourakis, Tânia; Yonamine, Maurício; Mantovani, Cínthia de C; Kirsten, Thiago B

    2016-01-01

    The use of smoked illicit drugs has spread dramatically, but few studies use proper devices to expose animals to inhalational abused drugs despite the availability of numerous smoking devices that mimic tobacco exposure in rodents. Therefore, the present study developed an inexpensive device to easily expose laboratory animals to smoked drugs. We used crack cocaine as the drug of abuse, and the cocaine plasma levels and the behaviors of animals intoxicated with the crack cocaine were evaluated to prove inhaled drug absorption and systemic activity. We developed an acrylic device with two chambers that were interconnected and separated by a hatch. Three doses of crack (100, 250, or 500 mg), which contained 63.7% cocaine, were burned in a pipe, and the rats were exposed to the smoke for 5 or 10 min (n=5/amount/period). Exposure to the 250-mg dose for 10 min achieved cocaine plasma levels that were similar to those of users (170 ng/mL). Behavioral evaluations were also performed to validate the methodology. Rats (n=10/group) for these evaluations were exposed to 250 mg of crack cocaine or air for 10 min, twice daily, for 28 consecutive days. Open-field evaluations were performed at three different periods throughout the experimental design. Exposed animals exhibited transient anorexia, increased motor activity, and shorter stays in central areas of the open field, which suggests reduced anxiety. Therefore, the developed model effectively exposed animals to crack cocaine, and this model may be useful for the investigation of other inhalational abused drugs. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Fentanyl Iontophoretic Transdermal System (IONSYS(®)) can be Safely used in the Hospital Environment with X-Rays, Computerized Tomography and Radiofrequency Identification Devices.

    Science.gov (United States)

    Lemke, John; Sardariani, Edmond; Phipps, Joseph Bradley; Patel, Niki; Itri, Loretta M; Caravelli, James; Viscusi, Eugene R

    2016-09-01

    Fentanyl iontophoretic transdermal system (fentanyl ITS, IONSYS(®)) is a patient-controlled analgesia system used for the management of acute postoperative pain, designed to be utilized in a hospital setting. The objective of the two studies was to determine if fentanyl ITS could be safely used with X-rays, computerized tomography (CT) scans and radiofrequency identification (RFID) devices. The ITS system has two components: controller and drug unit; the studies utilized ITS systems without fentanyl, referred to as the ITS Placebo system. The first study evaluated the effect of X-radiation on the operation of an ITS Placebo system. Five ITS Placebo systems were exposed to X-rays (20 and 200 mSv total radiation dose-the 200 mSv radiation dose represents a tenfold higher exposure than in clinical practice) while operating in the Ready Mode and five were exposed while operating in the Dose Mode. The second study evaluated the effect of RFID (worst-case scenario of direct contact with an RFID transmitter) on the operation of an ITS Placebo system. During these tests, observations of the user interface and measurements of output voltage confirmed proper function throughout all operational modes (Ready Mode, Dose Mode, End-of-Use Mode, and End-of-Life Mode). The ITS Placebo system met all specifications and no functional anomalies were observed during and following X-ray exposure at two radiation dose levels or exposure at six different combinations of RFID frequencies and field strengths. The performance of the ITS system was unaffected by X-ray exposure levels well beyond those associated with diagnostic X-rays and CT scans, and by exposure to radiofrequency field strengths typically generated by RFID devices. These results provide added confidence to clinicians that the fentanyl ITS system does not need to be removed during diagnostic X-rays and CT scans and can also be utilized in close proximity to RFID devices. The studies and writing of this manuscript were

  7. Image-guided radiofrequency ablation (RFA) of spinal tumors

    Energy Technology Data Exchange (ETDEWEB)

    Gevargez, Athour [Groenemeyer Institute of MicroTherapy, Bochum (Germany); Department of Radiology and Microtherapy, University of Witten/Herdecke, Bochum (Germany)], E-mail: gevargez@microtherapy.de; Groenemeyer, Dietrich H.W. [Groenemeyer Institute of MicroTherapy, Bochum (Germany); Department of Radiology and Microtherapy, University of Witten/Herdecke, Bochum (Germany)

    2008-02-15

    Purpose: To evaluate retrospectively the efficacy and safety of radiofrequency ablation (RFA) in patients with spinal tumors. Materials and methods: Forty-one patients (25 men, 16 women; age range, 46-82 years) with nonresectable primary or secondary tumor involvement of the spine unresponsive to chemo- and radiotherapy received RFA treatment. Two radiofrequency ablation systems, one with a cool-tip electrode and one with an expandable electrode catheter, were used. Both systems work impedance controlled with a power output of 150- 200 W. Each coagulation cycle lasted 12-15 min depending on tumor impedance. Several single RFA cycles of 15 min each were used for overlapping RFAs in tumors with diameters of more than 3 cm. Temperature was kept between 50 deg. C and 120 deg. C and was chosen according to spinal cord distance and patient heat tolerance during the ablation. Multi-slice computed tomography (CT) combined with C-arm fluoroscopy guided the intervention. Efficacy outcomes were assessed after about 6 weeks, 6 months, and more than 6 months using standardized questionnaires and indices regarding tumor pain, pain disability, functional activities, quality of life, neurological status, and tumor progression. Results: RFA significantly reduced tumor-induced pain within 6 weeks, improved daily activities, and maintained quality of life. Mean time to tumor progression was 730 {+-} 54 days (Kaplan-Meier estimate). No RFA-associated complications were reported. Conclusion: RFA of primary and secondary spinal tumors, which were unresponsive to chemo- and radiotherapy and prone to progression, is a safe, resource-saving, and highly effective percutaneous technique in patients with nonresectable spinal tumors.

  8. Radiofrequency electromagnetic fields emitted from base stations of DECT cordless phones and the risk of glioma and meningioma (Interphone Study Group, Germany)

    DEFF Research Database (Denmark)

    Schüz, Joachim; Böhler, Eva; Schlehofer, Brigitte

    2006-01-01

    The objective of this study was to test the hypothesis that exposure to continuous low-level radiofrequency electromagnetic fields (RF EMFs) increases the risk of glioma and meningioma. Participants in a population-based case-control study in Germany on the risk of brain tumors in relation...

  9. Human exposure monitoring and evaluation in the Arctic: the importance of understanding exposures to the development of public health policy.

    Science.gov (United States)

    Suk, William A; Avakian, Maureen D; Carpenter, Da