40 CFR 63.1044 - Standards-Separator vented to control device.

Code of Federal Regulations, 2010 CFR

2010-07-01

... outdoor exposure to wind, moisture, and sunlight; and the operating practices used for the separator on... operator shall inspect and monitor the air emission control equipment in accordance with the procedures...

40 CFR 63.1044 - Standards-Separator vented to control device.

Code of Federal Regulations, 2013 CFR

2013-07-01

... outdoor exposure to wind, moisture, and sunlight; and the operating practices used for the separator on... operator shall inspect and monitor the air emission control equipment in accordance with the procedures...

40 CFR 63.1044 - Standards-Separator vented to control device.

Code of Federal Regulations, 2014 CFR

2014-07-01

... outdoor exposure to wind, moisture, and sunlight; and the operating practices used for the separator on... operator shall inspect and monitor the air emission control equipment in accordance with the procedures...

40 CFR 63.943 - Standards-Surface impoundment vented to control device.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the surface impoundment; the effects of outdoor exposure to wind, moisture, and sunlight; and the... shall inspect and monitor the air emission control equipment in accordance with the procedures specified...

40 CFR 63.943 - Standards-Surface impoundment vented to control device.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the surface impoundment; the effects of outdoor exposure to wind, moisture, and sunlight; and the... shall inspect and monitor the air emission control equipment in accordance with the procedures specified...

40 CFR 63.1044 - Standards-Separator vented to control device.

Code of Federal Regulations, 2011 CFR

2011-07-01

... outdoor exposure to wind, moisture, and sunlight; and the operating practices used for the separator on... operator shall inspect and monitor the air emission control equipment in accordance with the procedures...

40 CFR 63.943 - Standards-Surface impoundment vented to control device.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the surface impoundment; the effects of outdoor exposure to wind, moisture, and sunlight; and the... shall inspect and monitor the air emission control equipment in accordance with the procedures specified...

21 CFR 872.1820 - Dental x-ray exposure alignment device.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Dental x-ray exposure alignment device. 872.1820... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1820 Dental x-ray exposure alignment device. (a) Identification. A dental x-ray exposure alignment device is a device intended to position x...

21 CFR 872.1820 - Dental x-ray exposure alignment device.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Dental x-ray exposure alignment device. 872.1820... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1820 Dental x-ray exposure alignment device. (a) Identification. A dental x-ray exposure alignment device is a device intended to position x...

21 CFR 872.1820 - Dental x-ray exposure alignment device.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental x-ray exposure alignment device. 872.1820... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1820 Dental x-ray exposure alignment device. (a) Identification. A dental x-ray exposure alignment device is a device intended to position x...

21 CFR 872.1820 - Dental x-ray exposure alignment device.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Dental x-ray exposure alignment device. 872.1820... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1820 Dental x-ray exposure alignment device. (a) Identification. A dental x-ray exposure alignment device is a device intended to position x...

21 CFR 872.1820 - Dental x-ray exposure alignment device.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Dental x-ray exposure alignment device. 872.1820... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1820 Dental x-ray exposure alignment device. (a) Identification. A dental x-ray exposure alignment device is a device intended to position x...

Digital micromirror device camera with per-pixel coded exposure for high dynamic range imaging.

PubMed

Feng, Wei; Zhang, Fumin; Wang, Weijing; Xing, Wei; Qu, Xinghua

2017-05-01

In this paper, we overcome the limited dynamic range of the conventional digital camera, and propose a method of realizing high dynamic range imaging (HDRI) from a novel programmable imaging system called a digital micromirror device (DMD) camera. The unique feature of the proposed new method is that the spatial and temporal information of incident light in our DMD camera can be flexibly modulated, and it enables the camera pixels always to have reasonable exposure intensity by DMD pixel-level modulation. More importantly, it allows different light intensity control algorithms used in our programmable imaging system to achieve HDRI. We implement the optical system prototype, analyze the theory of per-pixel coded exposure for HDRI, and put forward an adaptive light intensity control algorithm to effectively modulate the different light intensity to recover high dynamic range images. Via experiments, we demonstrate the effectiveness of our method and implement the HDRI on different objects.

Electron-beam lithography with character projection technique for high-throughput exposure with line-edge quality control

NASA Astrophysics Data System (ADS)

Ikeno, Rimon; Maruyama, Satoshi; Mita, Yoshio; Ikeda, Makoto; Asada, Kunihiro

2016-07-01

The high throughput of character projection (CP) electron-beam (EB) lithography makes it a promising technique for low-to-medium volume device fabrication with regularly arranged layouts, such as for standard-cell logics and memory arrays. However, non-VLSI applications such as MEMS and MOEMS may not be able to fully utilize the benefits of the CP method due to the wide variety of layout figures including curved and oblique edges. In addition, the stepwise shapes that appear because of the EB exposure process often result in intolerable edge roughness, which degrades device performances. In this study, we propose a general EB lithography methodology for such applications utilizing a combination of the CP and variable-shaped beam methods. In the process of layout data conversion with CP character instantiation, several control parameters were optimized to minimize the shot count, improve the edge quality, and enhance the overall device performance. We have demonstrated EB shot reduction and edge-quality improvement with our methodology by using a leading-edge EB exposure tool, ADVANTEST F7000S-VD02, and a high-resolution hydrogen silsesquioxane resist. Atomic force microscope observations were used to analyze the resist edge profiles' quality to determine the influence of the control parameters used in the data conversion process.

Assessment of risks of EMI for personal medical electronic devices (PMEDs) from emissions of millimeter-wave security screening systems

NASA Astrophysics Data System (ADS)

Witters, Donald; Bassen, Howard; Guag, Joshua; Addissie, Bisrat; LaSorte, Nickolas; Rafai, Hazem

2013-06-01

This paper describes research and testing of a representative group of high priority body worn and implantable personal medical electronic devices (PMEDs) for exposure to millimeter wave (MMW) advanced imaging technology (AIT) security systems used at airports. The sample PMEDs included in this study were implantable cardiac pacemakers, ICDs, neurostimulators and insulin pumps. These PMEDs are designed and tested for susceptibility to electromagnetic interference (EMI) under the present standards for medical device electromagnetic compatibility (EMC). However, the present standards for medical equipment do not address exposure to the much higher frequency fields that are emitted by MMW security systems. Initial AIT emissions measurements were performed to assess the PMED and passenger exposures. Testing protocols were developed and testing methods were tailored to the type of PMED. In addition, a novel exposure simulation system was developed to allow controlled EMC testing without the need of the MMW AIT system. Methodology, test results, and analysis are presented, along with an assessment of the human exposure and risks for PMED users. The results on this study reveal no effects on the medical devices from the exposure to the MMW security system. Furthermore, the human exposure measurements and analysis showed levels well below applicable standard, and the risks for PMED users and others we assessed to be very low. These findings apply to the types of PMEDs used in the study though these findings might suggest that the risks for other, similar PMEDs would likely be similar.

Cultivation in the Newer Media Environment.

ERIC Educational Resources Information Center

Perse, Elizabeth M.; And Others

1994-01-01

Tests the impact of cable, VCRs, and remote control devices on fear of crime and interpersonal mistrust. Finds that interpersonal mistrust was linked to greater exposure to cable's broadcast-type channels, but fear of crime and mistrust were negatively related to increased exposure to specialized cable channels. Finds fear of crime linked…

The Importance of Moisture in Hybrid Lead Halide Perovskite Thin Film Fabrication.

PubMed

Eperon, Giles E; Habisreutinger, Severin N; Leijtens, Tomas; Bruijnaers, Bardo J; van Franeker, Jacobus J; deQuilettes, Dane W; Pathak, Sandeep; Sutton, Rebecca J; Grancini, Giulia; Ginger, David S; Janssen, Rene A J; Petrozza, Annamaria; Snaith, Henry J

2015-09-22

Moisture, in the form of ambient humidity, has a significant impact on methylammonium lead halide perovskite films. In particular, due to the hygroscopic nature of the methylammonium component, moisture plays a significant role during film formation. This issue has so far not been well understood and neither has the impact of moisture on the physical properties of resultant films. Herein, we carry out a comprehensive and well-controlled study of the effect of moisture exposure on methylammonium lead halide perovskite film formation and properties. We find that films formed in higher humidity atmospheres have a less continuous morphology but significantly improved photoluminescence, and that film formation is faster. In photovoltaic devices, we find that exposure to moisture, either in the precursor solution or in the atmosphere during formation, results in significantly improved open-circuit voltages and hence overall device performance. We then find that by post-treating dry films with moisture exposure, we can enhance photovoltaic performance and photoluminescence in a similar way. The enhanced photoluminescence and open-circuit voltage imply that the material quality is improved in films that have been exposed to moisture. We determine that this improvement stems from a reduction in trap density in the films, which we postulate to be due to the partial solvation of the methylammonium component and "self-healing" of the perovskite lattice. This work highlights the importance of controlled moisture exposure when fabricating high-performance perovskite devices and provides guidelines for the optimum environment for fabrication. Moreover, we note that often an unintentional water exposure is likely responsible for the high performance of solar cells produced in some laboratories, whereas careful synthesis and fabrication in a dry environment will lead to lower-performing devices.

A solution for exposure tool optimization at the 65-nm node and beyond

NASA Astrophysics Data System (ADS)

Itai, Daisuke

2007-03-01

As device geometries shrink, tolerances for critical dimension, focus, and overlay control decrease. For the stable manufacture of semiconductor devices at (and beyond) the 65nm node, both performance variability and drift in exposure tools are no longer negligible factors. With EES (Equipment Engineering System) as a guidepost, hopes of improving productivity of semiconductor manufacturing are growing. We are developing a system, EESP (Equipment Engineering Support Program), based on the concept of EES. The EESP system collects and stores large volumes of detailed data generated from Canon lithographic equipment while product is being manufactured. It uses that data to monitor both equipment characteristics and process characteristics, which cannot be examined without this system. The goal of EESP is to maximize equipment capabilities, by feeding the result back to APC/FDC and the equipment maintenance list. This was a collaborative study of the system's effectiveness at the device maker's factories. We analyzed the performance variability of exposure tools by using focus residual data. We also attempted to optimize tool performance using the analyzed results. The EESP system can make the optimum performance of exposure tools available to the device maker.

Evaluation of the antioxidant capacity and preventive effects of a topical emulsion and its vehicle control on the skin response to UV exposure.

PubMed

Zhai, H; Behnam, S; Villarama, C D; Arens-Corell, M; Choi, M J; Maibach, H I

2005-01-01

Supplying topical exogenous antioxidants to the skin may prevent or minimize free radical-induced damaging. This study determines antioxidative capacity of a topical skin care emulsion (an oil-in-water vitamin E-containing formulation) versus its vehicle on human skin that was exposed to ultraviolet radiation (UVR) by utilizing a photochemiluminescence device and biophysical methods. Ten healthy Caucasians (3 male and 7 female; mean age 47 +/- 10 years) were enrolled. In a randomized and double-blind manner, a pH-balanced vitamin E emulsion or its vehicle control was applied onto predesignated forearm prior to UVR exposure. Thirty minutes after application, these test sites were exposed to a UV light to induce the minimal erythema dose. One untreated site served as a blank control. Visual scoring and instrumental measurements were recorded at baseline and at 24 h and 48 h thereafter. At day 3, after completing instrumental measurements, each test site was stripped three times in a consecutive manner with a proprietary adhesive tape disc. These tapes were quantified for antioxidant capacity using a photochemiluminescence device. Vitamin E emulsion and vehicle control significantly (p < 0.05) suppressed visual scores when compared with blank control at day 2 and day 3 after UV exposure. However, vitamin E emulsion showed significantly (p < 0.05) lower visual scores when compared with vehicle control at day 2 and day 3 after UV exposure.Also,vitamin E emulsion and its vehicle control significantly (p < 0.05) diminished skin color measurement (a*) values when compared with blank control at day 2 and day 3 after UV exposure. At day 2 after UV exposure, only vitamin E emulsion significantly (p < 0.05) reduced skin blood flow volume when compared with blank control. Vitamin E emulsion and its vehicle control showed significant (p < 0.05) reduction of blood flow volume when compared with blank control at day 3 after UV exposure. Vitamin E emulsion and its vehicle control proved effective in preventing induction of erythema and reducing inflammatory damage caused by UV exposure. The effect of vitamin E emulsion exceeded that of an 'active control'. Copyright 2005 S. Karger AG, Basel

A Comparison between Temperature-Controlled Laminar Airflow Device and a Room Air-Cleaner in Reducing Exposure to Particles While Asleep

PubMed Central

Spilak, Michal P.; Sigsgaard, Torben; Takai, Hisamitsu; Zhang, Guoqiang

2016-01-01

People spend approximately one third of their life sleeping. Exposure to pollutants in the sleep environment often leads to a variety of adverse health effects, such as development and exacerbation of asthma. Avoiding exposure to these pollutants by providing a sufficient air quality in the sleep environment might be a feasible method to alleviate these health symptoms. We performed full-scale laboratory measurements using a thermal manikin positioned on an experimental bed. Three ventilation settings were tested: with no filtration system operated, use of portable air cleaner and use of a temperature-controlled laminar airflow (TLA) device. The first part of the experiment investigated the air-flow characteristics in the breathing zone. In the second part, particle removal efficiency was estimated. Measured in the breathing zone, the room air cleaner demonstrated high turbulence intensity, high velocity and turbulence diffusivity level, with a particle reduction rate of 52% compared to baseline after 30 minutes. The TLA device delivered a laminar airflow to the breathing zone with a reduction rate of 99.5%. During a periodical duvet lifting mimicking a subject’s movement in bed, the particle concentration was significantly lower with the TLA device compared to the room air cleaner. The TLA device provided a barrier which significantly reduced the introduction of airborne particles into the breathing zone. Further studies should be conducted for the understanding of the transport of resuspended particles between the duvet and the laying body. PMID:27898693

A Comparison between Temperature-Controlled Laminar Airflow Device and a Room Air-Cleaner in Reducing Exposure to Particles While Asleep.

PubMed

Spilak, Michal P; Sigsgaard, Torben; Takai, Hisamitsu; Zhang, Guoqiang

2016-01-01

People spend approximately one third of their life sleeping. Exposure to pollutants in the sleep environment often leads to a variety of adverse health effects, such as development and exacerbation of asthma. Avoiding exposure to these pollutants by providing a sufficient air quality in the sleep environment might be a feasible method to alleviate these health symptoms. We performed full-scale laboratory measurements using a thermal manikin positioned on an experimental bed. Three ventilation settings were tested: with no filtration system operated, use of portable air cleaner and use of a temperature-controlled laminar airflow (TLA) device. The first part of the experiment investigated the air-flow characteristics in the breathing zone. In the second part, particle removal efficiency was estimated. Measured in the breathing zone, the room air cleaner demonstrated high turbulence intensity, high velocity and turbulence diffusivity level, with a particle reduction rate of 52% compared to baseline after 30 minutes. The TLA device delivered a laminar airflow to the breathing zone with a reduction rate of 99.5%. During a periodical duvet lifting mimicking a subject's movement in bed, the particle concentration was significantly lower with the TLA device compared to the room air cleaner. The TLA device provided a barrier which significantly reduced the introduction of airborne particles into the breathing zone. Further studies should be conducted for the understanding of the transport of resuspended particles between the duvet and the laying body.

Emergency department evaluation after conducted energy weapon use: review of the literature for the clinician.

PubMed

Vilke, Gary M; Bozeman, William P; Chan, Theodore C

2011-05-01

Conductive energy weapons (CEWs) are used daily by law enforcement, and patients are often brought to an emergency department (ED) for medical clearance. To review the medical literature on the topic of CEWs and to offer evidence-based recommendations to Emergency Physicians for evaluation and treatment of patients who have received a CEW exposure. A MEDLINE literature search from 1988 to 2010 was performed and limited to human studies published from January 1988 to January 20, 2010 for English language articles with the following keywords: TASER, conductive energy device(s), electronic weapon(s), conductive energy weapon(s), non-lethal weapon(s), conducted energy device(s), conducted energy weapon(s), conductive electronic device(s), and electronic control device(s). Studies identified then underwent a structured review from which results could be evaluated. There were 140 articles on CEWs screened, and 20 appropriate articles were rigorously reviewed and recommendations given. These studies did not report any evidence of dangerous laboratory abnormalities, physiologic changes, or immediate or delayed cardiac ischemia or dysrhythmias after exposure to CEW electrical discharges of up to 15 s. The current medical literature does not support routine performance of laboratory studies, electrocardiograms, or prolonged ED observation or hospitalization for ongoing cardiac monitoring after CEW exposure in an otherwise asymptomatic awake and alert patient. Copyright © 2011 Elsevier Inc. All rights reserved.

29 CFR 1915.89 - Control of hazardous energy (lockout/tags-plus).

Code of Federal Regulations, 2012 CFR

2012-07-01

... employee: (A) Sign a group tag (or a group tag equivalent), attach a personal identification device to a... group tag (or the group tag equivalent), remove the personal identification device, or perform a... safe exposure status of each authorized employee, and (b) signs a group tag (or a group tag equivalent...

29 CFR 1915.89 - Control of hazardous energy (lockout/tags-plus).

Code of Federal Regulations, 2013 CFR

2013-07-01

... employee: (A) Sign a group tag (or a group tag equivalent), attach a personal identification device to a... group tag (or the group tag equivalent), remove the personal identification device, or perform a... safe exposure status of each authorized employee, and (b) signs a group tag (or a group tag equivalent...

29 CFR 1915.89 - Control of hazardous energy (lockout/tags-plus).

Code of Federal Regulations, 2014 CFR

2014-07-01

... employee: (A) Sign a group tag (or a group tag equivalent), attach a personal identification device to a... group tag (or the group tag equivalent), remove the personal identification device, or perform a... safe exposure status of each authorized employee, and (b) signs a group tag (or a group tag equivalent...

A new passive radon-thoron discriminative measurement system.

PubMed

Sciocchetti, G; Sciocchetti, A; Giovannoli, P; DeFelice, P; Cardellini, F; Cotellessa, G; Pagliari, M

2010-10-01

A new passive radon-thoron discriminative measurement system has been developed for monitoring radon and thoron individually. It consists of a 'couple' of passive integrating devices with a CR39 nuclear track detector (NTD). The experimental prototype is based on the application of a new concept of NTD instrument developed at ENEA, named Alpha-PREM, acronym of piston radon exposure meter, which allows controlling the detector exposure with a patented sampling technique (Int. Eu. Pat. and US Pat.). The 'twin diffusion chambers system' was based on two A-PREM devices consisting of the standard device, named NTD-Rn, and a modified version, named NTD-Rn/Tn, which was set up to improve thoron sampling efficiency of the diffusion chamber, without changing the geometry and the start/stop function of the NTD-Rn device. Coupling devices fitted on each device allowed getting a system, which works as a double-chamber structure when deployed at the monitoring position. In this paper both technical and physical aspects are considered.

Pilot study of methods and equipment for in-home noise level measurements.

PubMed

Neitzel, Richard L; Heikkinen, Maire S A; Williams, Christopher C; Viet, Susan Marie; Dellarco, Michael

2015-01-15

Knowledge of the auditory and non-auditory effects of noise has increased dramatically over the past decade, but indoor noise exposure measurement methods have not advanced appreciably, despite the introduction of applicable new technologies. This study evaluated various conventional and smart devices for exposure assessment in the National Children's Study. Three devices were tested: a sound level meter (SLM), a dosimeter, and a smart device with a noise measurement application installed. Instrument performance was evaluated in a series of semi-controlled tests in office environments over 96-hour periods, followed by measurements made continuously in two rooms (a child's bedroom and a most used room) in nine participating homes over a 7-day period with subsequent computation of a range of noise metrics. The SLMs and dosimeters yielded similar A-weighted average noise levels. Levels measured by the smart devices often differed substantially (showing both positive and negative bias, depending on the metric) from those measured via SLM and dosimeter, and demonstrated attenuation in some frequency bands in spectral analysis compared to SLM results. Virtually all measurements exceeded the Environmental Protection Agency's 45 dBA day-night limit for indoor residential exposures. The measurement protocol developed here can be employed in homes, demonstrates the possibility of measuring long-term noise exposures in homes with technologies beyond traditional SLMs, and highlights potential pitfalls associated with measurements made by smart devices.

Short-Term Exposure to Electromagnetic Fields Generated by Mobile Phone Jammers Decreases the Fasting Blood Sugar in Adult Male Rats.

PubMed

Shekoohi Shooli, F; Mortazavi, S A R; Jarideh, S; Nematollahii, S; Yousefi, F; Haghani, M; Mortazavi, S M J; Shojaei-Fard, M B

2016-03-01

Substantial evidence indicates that exposure to electromagnetic fields (EMF) above certain levels can affect human health through triggering some biological responses. According to WHO, short-term exposure to EMF at the levels present in the home/environment do not cause any apparent detrimental effects in healthy individuals. However, now, there is a debate on whether long-term exposure to low level EMF can evoke detrimental biological responses. Although based on the Communications Act of 1934, selling, advertising, using, or importing mobile jammers which block cell phone calls and text messages are illegal acts, in some countries these devices are being used for security purpose and for prevention of cheating during examinations. In this study 30 male Wistar rats were randomly divided into 3 groups of 10 each. The control group received no radiation. The sham exposure group was exposed to a switched-off jammer device. After fasting for 12 hours, the exposure group was exposed to EMFs at a distance of 50 cm from the jammer. Blood samples were collected from the tail vein after 24, 48 and72 hours and fasting blood sugar was measured by using a common blood glucose monitor (BIONIME GM110, Taiwan). The significance level was considered 5% and SPSS Ver. 21 was used for statistical analysis. The data were analyzed by ANOVA followed by Tukey's test. A statistically significant difference was observed between blood sugar level in the control and exposure groups after 24, 48 and 72 hours of continuous irradiation (p values were <0.001, <0.001 and 0.002, respectively). No significant difference was found between the level of fasting blood sugar in control and sham groups. Short-term exposure to electromagnetic field generated by mobile phone jammer can reduce blood sugar level in adult male rats. These findings, in contrast with our previous results, lead us to this conclusion that the use of these signal blocking devices in very specific circumstances may have some therapeutic effects. However, further studies have to be performed to find out the exact mechanism by which Jammer EMFs reduce fasting blood sugar.

Photovoltaic studies of Dye Sensitized Solar cells Fabricated from Microwave Exposed Photo anodes

NASA Astrophysics Data System (ADS)

Ramachandran, Anju; Sreekala, C. O.; Sreelatha, K. S.; Jinchu, I.

2018-02-01

The configuration of Dye Sensitized solar cells (DSSC), consists of sintered nanoparticle titanium dioxide film, dyes, electrolyte and counter electrodes. Upon the absorption of photons by the dye molecules, excitons are generated, subsequently electrons are injected into the TiO2 photoanode. Afterward the electrons injected into the TiO2 photoanode, to produce photocurrent, scavenged by redox couple, and the hole transport to the photo cathode. The power conversion efficiency of the device depends on the amount of dye adsorbed by the photoanode. This paper explores in enhancing the efficiency of the device by controlled microwave exposure. With same exposure time, the photoanode is exposed at three different frequencies. SEM analysis is carried out to find the porosity of the photoanode on exposure. Current density is found to have an effect on microwave exposure.

Personal medical electronic devices and walk-through metal detector security systems: assessing electromagnetic interference effects.

PubMed

Guag, Joshua; Addissie, Bisrat; Witters, Donald

2017-03-20

There have been concerns that Electromagnetic security systems such as walk-through metal detectors (WTMDs) can potentially cause electromagnetic interference (EMI) in certain active medical devices including implantable cardiac pacemakers and implantable neurostimulators. Incidents of EMI between WTMDs and active medical devices also known as personal medical electronic devices (PMED) continue to be reported. This paper reports on emission measurements of sample WTMDs and testing of 20 PMEDs in a WTMD simulation system. Magnetic fields from sample WTMD systems were characterized for emissions and exposure of certain PMEDs. A WTMD simulator system designed and evaluated by FDA in previous studies was used to mimic the PMED exposures to the waveform from sample WTMDs. The simulation system allows for controlled PMED exposure enabling careful study with adjustable magnetic field strengths and exposure duration, and provides flexibility for PMED exposure at elevated levels in order to study EMI effects on the PMED. The PMED samples consisted of six implantable cardiac pacemakers, six implantable cardioverter defibrillators (ICD), five implantable neurostimulators, and three insulin pumps. Each PMED was exposed in the simulator to the sample WTMD waveforms using methods based on appropriate consensus test standards for each of the device type. Testing the sample PMEDs using the WTMD simulator revealed EMI effects on two implantable pacemakers and one implantable neurostimulator for exposure field strength comparable to actual WTMD field strength. The observed effects were transient and the PMEDs returned to pre-exposure operation within a few seconds after removal from the simulated WTMD exposure fields. No EMI was observed for the sample ICDs or insulin pumps. The findings are consistent with earlier studies where certain sample PMEDs exhibited EMI effects. Clinical implications were not addressed in this study. Additional studies are needed to evaluate potential PMED EMI susceptibilities over a broader range of security systems.

Paper-based microfluidics with an erodible polymeric bridge giving controlled release and timed flow shutoff.

PubMed

Jahanshahi-Anbuhi, Sana; Henry, Aleah; Leung, Vincent; Sicard, Clémence; Pennings, Kevin; Pelton, Robert; Brennan, John D; Filipe, Carlos D M

2014-01-07

Water soluble pullulan films were formatted into paper-based microfluidic devices, serving as a controlled time shutoff valve. The utility of the valve was demonstrated by a one-step, fully automatic implementation of a complex pesticide assay requiring timed, sequential exposure of an immobilized enzyme layer to separate liquid streams. Pullulan film dissolution and the capillary wicking of aqueous solutions through the device were measured and modeled providing valve design criteria. The films dissolve mainly by surface erosion, meaning the film thickness mainly controls the shutoff time. This method can also provide time-dependent sequential release of reagents without compromising the simplicity and low cost of paper-based devices.

Long-life mission reliability for outer planet atmospheric entry probes

NASA Technical Reports Server (NTRS)

Mccall, M. T.; Rouch, L.; Maycock, J. N.

1976-01-01

The results of a literature analysis on the effects of prolonged exposure to deep space environment on the properties of outer planet atmospheric entry probe components are presented. Materials considered included elastomers and plastics, pyrotechnic devices, thermal control components, metal springs and electronic components. The rates of degradation of each component were determined and extrapolation techniques were used to predict the effects of exposure for up to eight years to deep space. Pyrotechnic devices were aged under accelerated conditions to an equivalent of eight years in space and functionally tested. Results of the literature analysis of the selected components and testing of the devices indicated that no severe degradation should be expected during an eight year space mission.

Multilayer Microfluidic Devices Created From A Single Photomask

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

Kelly, Ryan T.; Sheen, Allison M.; Jambovane, Sachin R.

2013-08-28

The time and expense associated with high quality photomask production can discourage the creation of multilayer microfluidic devices, as each layer currently requires a separate photomask. Here we describe an approach in which multilayer microfabricated devices can be created from a single photomask. The separate layers and their corresponding alignment marks are arranged in separate halves of the mask for two layer devices or quadrants for four layer devices. Selective exposure of the photomask features and rotation of the device substrate between exposures result in multiple copies of the devices on each wafer. Subsequent layers are aligned to patterned featuresmore » on the substrate with the same alignment accuracy as when multiple photomasks are used. We demonstrate this approach for fabricating devices employing multilayer soft lithography (MSL) for pneumatic valving. MSL devices containing as many as 5 layers (4 aligned fluidic layers plus a manually aligned control layer) were successfully created using this approach. Device design is also modularized, enabling the presence or absence of features as well as channel heights to be selected independently from one another. The use of a single photomask to create multilayer devices results in a dramatic savings of time and/or money required to advance from device design to completed prototype.« less

Mycological studies housed in the Apollo 16 microbial ecology evaluation device

NASA Technical Reports Server (NTRS)

Volz, P. A.

1973-01-01

Survival, death, and phenotype count have yielded variation in the number of fungi recovered from the controls and the flight exposed cuvettes during preliminary analysis of postflight first phase data. Also the preliminary analysis was indicative that fungi exposed to specific space flight conditions demonstrated variable survival rates and phenotype counts. Specific space flight conditions included full light space exposure for Chaetomium globosum, exposure at 300- and 254-nanometer wavelengths for Rhodotorula rubra, full light and 280-nanometer wavelength exposure for Trichophyton terrestre, and 254-nanometer wavelength exposure for Saccharomyces cerevisiae. In general, phenotype counts for flight cuvettes and survival rates for control cuvettes were higher compared with the remaining cuvettes.

Test-retest of self-reported exposure to artificial tanning devices, self-tanning creams, and sun sensitivity showed consistency.

PubMed

Beane Freeman, Laura E; Dennis, Leslie K; Lynch, Charles F; Lowe, John B; Clarke, William R

2005-04-01

Exposure to ultraviolet radiation has consistently been linked to an increased risk of melanoma. Epidemiologic studies are susceptible to measurement error, which can distort the magnitude of observed effects. Although the reliability of self-report of many sun exposure factors has been previously described in several studies, self-report of use of artificial tanning devices and self-tanning creams has been less well characterized. A mailed survey was re-administered 2-4 weeks after completion of the initial survey to 76 randomly selected participants in a case-control study of melanoma. Cases and controls were individuals diagnosed in 1999 and 2000 who were ascertained from the Iowa Cancer Registry in 2002. We assessed the consistency of self-reported use of sunlamps and self-tanning creams, sun sensitivity, and history of sunburns. There was substantial reliability in reporting the use of sunlamps or self-tanning creams (cases: Kappa (kappa)=1.0 for both exposures; controls: kappa=0.71 and 0.87, respectively). kappa estimates of 0.62-0.78 were found for overall reliability of several sun sensitivity factors. Overall, the survey instrument demonstrated substantial reproducibility for factors related to the use of sunlamps or tanning beds, self-tanning creams, and sun sensitivity factors.

Improving the accuracy of smart devices to measure noise exposure.

PubMed

Roberts, Benjamin; Kardous, Chucri; Neitzel, Richard

2016-11-01

Occupational noise exposure is one of the most frequent hazards present in the workplace; up to 22 million workers have potentially hazardous noise exposures in the U.S. As a result, noise-induced hearing loss is one of the most common occupational injuries in the U.S. Workers in manufacturing, construction, and the military are at the highest risk for hearing loss. Despite the large number of people exposed to high levels of noise at work, many occupations have not been adequately evaluated for noise exposure. The objective of this experiment was to investigate whether or not iOS smartphones and other smart devices (Apple iPhones and iPods) could be used as reliable instruments to measure noise exposures. For this experiment three different types of microphones were tested with a single model of iPod and three generations of iPhones: the internal microphones on the device, a low-end lapel microphone, and a high-end lapel microphone marketed as being compliant with the International Electrotechnical Commission's (IEC) standard for a Class 2-microphone. All possible combinations of microphones and noise measurement applications were tested in a controlled environment using several different levels of pink noise ranging from 60-100 dBA. Results were compared to simultaneous measurements made using a Type 1 sound level measurement system. Analysis of variance and Tukey's honest significant difference (HSD) test were used to determine if the results differed by microphone or noise measurement application. Levels measured with external microphones combined with certain noise measurement applications did not differ significantly from levels measured with the Type 1 sound measurement system. Results showed that it may be possible to use iOS smartphones and smart devices, with specific combinations of measurement applications and calibrated external microphones, to collect reliable, occupational noise exposure data under certain conditions and within the limitations of the device. Further research is needed to determine how these devices compare to traditional noise dosimeter under real-world conditions.

Controllable Growth of Perovskite Films by Room-Temperature Air Exposure for Efficient Planar Heterojunction Photovoltaic Cells

DOE PAGES

Yang, Bin; Dyck, Ondrej; Poplawsky, Jonathan; ...

2015-12-01

A two-step-solution-processing approach has been established to grow void-free perovskite films for low-cost and high-performance planar heterojunction photovoltaic devices. We generally applied a high-temperature thermal annealing treatment in order to drive the diffusion of CH 3NH 3I precursor molecules into the compact PbI 2 layer to form perovskite films. But, thermal annealing for extended periods would lead to degraded device performance due to the defects generated by decomposition of perovskite into PbI 2. In this work, we explored a controllable layer-by-layer spin-coating method to grow bilayer CH 3NH 3I/PbI 2 films, and then drive the interdiffusion between PbI 2 andmore » CH 3NH 3I layers by a simple room-temperature-air-exposure for making well-oriented, highly-crystalline perovskite films without thermal annealing. This high degree of crystallinity resulted in a carrier diffusion length of ~ 800 nm and high device efficiency of 15.6%, which is comparable to the reported values from thermally-annealed perovskite films based counterparts. Finally, the simplicity and high device performance of this processing approach is highly promising for direct integration into industrial-scale device manufacture.« less

Application of clotrimazole via a novel controlled release device provides potent retinal protection.

PubMed

Nezhad, Zhaleh Kashkouli; Nagai, Nobuhiro; Yamamoto, Kotaro; Kaji, Hirokazu; Nishizawa, Matsuhiko; Saya, Hideyuki; Nakazawa, Toru; Abe, Toshiaki

2015-09-01

Age-related macular degeneration is the leading cause of legal blindness among older individuals. Therefore, the development of new therapeutic agents and optimum drug delivery systems for its treatment are crucial. In this study, we investigate whether clotrimazole (CLT) is capable of protecting retinal cells against oxidative-induced injury and the possible inhibitory effect of a sustained CLT-release device against light-induced retinal damage in rats. In vitro results indicated pretreatment of immortalized retinal pigment epithelium cells (RPE-J cells) with 10-50 µM CLT before exposure to oxygen/glucose deprivation conditions for 48 h decreased the extent of cell death, attenuated the percentage of reactive oxygen species-positive cells, and decreased the levels of cleaved caspase-3. The device consists of a separately fabricated reservoir, a CLT formulation, and a controlled release cover, which are made of poly(ethyleneglycol) dimethacrylate (PEGDM) and tri(ethyleneglycol) dimethacrylate (TEGDM). The release rate of CLT was successfully tuned by changing the ratio of PEGDM/TEGDM in the cover. In vivo results showed that use of a CLT-loaded device lessened the reduction of electroretinographic amplitudes after light exposure. These findings indicate that the application of a polymeric CLT-loaded device may be a promising method for the treatment of some retinal disorders.

Exposure to Visible Light Emitted from Smartphones and Tablets Increases the Proliferation of Staphylococcus aureus: Can this be Linked to Acne?

PubMed Central

Taheri, M.; Darabyan, M.; Izadbakhsh, E.; Nouri, F.; Haghani, M.; Mortazavi, S.A.R.; Mortazavi, G.; Mortazavi, S.M.J.; Moradi, M.

2017-01-01

Background: Due to rapid advances in modern technologies such as telecommunication technology, the world has witnessed an exponential growth in the use of digital handheld devices (e.g. smartphones and tablets). This drastic growth has resulted in increased global concerns about the safety of these devices. Smartphones, tablets, laptops, and other digital screens emit high levels of short-wavelength visible light (i.e. blue color region in the visible light spectrum). Material and Methods: At a dark environment, Staphylococcus aureus bacteria were exposed to the light emitted from common tablets/smartphones. The control samples were exposed to the same intensity of light generated by a conventional incandescent light bulb. The growth rate of bacteria was examined by measuring the optical density (OD) at 625 nm by using a spectrophotometer before the light exposure and after 30 to 330 minutes of light exposure. Results: The growth rates of bacteria in both smartphone and tablet groups were higher than that of the control group and the maximum smartphone/control and tablet/control growth ratios were observed in samples exposed to digital screens’ light for 300 min (ratios of 3.71 and 3.95, respectively). Conclusion: To the best of our knowledge, this is the first study that investigates the effect of exposure to light emitted from digital screens on the proliferation of Staphylococcus aureus and its association with acne pathogenesis. Our findings show that exposure to short-wavelength visible light emitted from smartphones and tablets can increase the proliferation of Staphylococcus aureus. PMID:28580338

JPL noise control program

NASA Technical Reports Server (NTRS)

Klascius, A. F.

1975-01-01

Exposures of personnel to noise pollution at the Jet Propulsion Laboratories, Pasadena, California, were investigated. As a result of the study several protective measures were taken: (1) employees exposed to noise hazards were required to wear ear-protection devices, (2) mufflers and air diversion devices were installed around the wind tunnels; and (3) all personnel that are required to wear ear protection are given annual audimeter tests.

Interventions to prevent occupational noise-induced hearing loss.

PubMed

Tikka, Christina; Verbeek, Jos H; Kateman, Erik; Morata, Thais C; Dreschler, Wouter A; Ferrite, Silvia

2017-07-07

This is the second update of a Cochrane Review originally published in 2009. Millions of workers worldwide are exposed to noise levels that increase their risk of hearing disorders. There is uncertainty about the effectiveness of hearing loss prevention interventions. To assess the effectiveness of non-pharmaceutical interventions for preventing occupational noise exposure or occupational hearing loss compared to no intervention or alternative interventions. We searched the CENTRAL; PubMed; Embase; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; and OSH UPDATE to 3 October 2016. We included randomised controlled trials (RCT), controlled before-after studies (CBA) and interrupted time-series (ITS) of non-clinical interventions under field conditions among workers to prevent or reduce noise exposure and hearing loss. We also collected uncontrolled case studies of engineering controls about the effect on noise exposure. Two authors independently assessed study eligibility and risk of bias and extracted data. We categorised interventions as engineering controls, administrative controls, personal hearing protection devices, and hearing surveillance. We included 29 studies. One study evaluated legislation to reduce noise exposure in a 12-year time-series analysis but there were no controlled studies on engineering controls for noise exposure. Eleven studies with 3725 participants evaluated effects of personal hearing protection devices and 17 studies with 84,028 participants evaluated effects of hearing loss prevention programmes (HLPPs). Effects on noise exposure Engineering interventions following legislationOne ITS study found that new legislation in the mining industry reduced the median personal noise exposure dose in underground coal mining by 27.7 percentage points (95% confidence interval (CI) -36.1 to -19.3 percentage points) immediately after the implementation of stricter legislation. This roughly translates to a 4.5 dB(A) decrease in noise level. The intervention was associated with a favourable but statistically non-significant downward trend in time of the noise dose of -2.1 percentage points per year (95% CI -4.9 to 0.7, 4 year follow-up, very low-quality evidence). Engineering intervention case studiesWe found 12 studies that described 107 uncontrolled case studies of immediate reductions in noise levels of machinery ranging from 11.1 to 19.7 dB(A) as a result of purchasing new equipment, segregating noise sources or installing panels or curtains around sources. However, the studies lacked long-term follow-up and dose measurements of workers, and we did not use these studies for our conclusions. Hearing protection devicesIn general hearing protection devices reduced noise exposure on average by about 20 dB(A) in one RCT and three CBAs (57 participants, low-quality evidence). Two RCTs showed that, with instructions for insertion, the attenuation of noise by earplugs was 8.59 dB better (95% CI 6.92 dB to 10.25 dB) compared to no instruction (2 RCTs, 140 participants, moderate-quality evidence). Administrative controls: information and noise exposure feedbackOn-site training sessions did not have an effect on personal noise-exposure levels compared to information only in one cluster-RCT after four months' follow-up (mean difference (MD) 0.14 dB; 95% CI -2.66 to 2.38). Another arm of the same study found that personal noise exposure information had no effect on noise levels (MD 0.30 dB(A), 95% CI -2.31 to 2.91) compared to no such information (176 participants, low-quality evidence). Effects on hearing loss Hearing protection devicesIn two studies the authors compared the effect of different devices on temporary threshold shifts at short-term follow-up but reported insufficient data for analysis. In two CBA studies the authors found no difference in hearing loss from noise exposure above 89 dB(A) between muffs and earplugs at long-term follow-up (OR 0.8, 95% CI 0.63 to 1.03 ), very low-quality evidence). Authors of another CBA study found that wearing hearing protection more often resulted in less hearing loss at very long-term follow-up (very low-quality evidence). Combination of interventions: hearing loss prevention programmesOne cluster-RCT found no difference in hearing loss at three- or 16-year follow-up between an intensive HLPP for agricultural students and audiometry only. One CBA study found no reduction of the rate of hearing loss (MD -0.82 dB per year (95% CI -1.86 to 0.22) for a HLPP that provided regular personal noise exposure information compared to a programme without this information.There was very-low-quality evidence in four very long-term studies, that better use of hearing protection devices as part of a HLPP decreased the risk of hearing loss compared to less well used hearing protection in HLPPs (OR 0.40, 95% CI 0.23 to 0.69). Other aspects of the HLPP such as training and education of workers or engineering controls did not show a similar effect.In three long-term CBA studies, workers in a HLPP had a statistically non-significant 1.8 dB (95% CI -0.6 to 4.2) greater hearing loss at 4 kHz than non-exposed workers and the confidence interval includes the 4.2 dB which is the level of hearing loss resulting from 5 years of exposure to 85 dB(A). In addition, of three other CBA studies that could not be included in the meta-analysis, two showed an increased risk of hearing loss in spite of the protection of a HLPP compared to non-exposed workers and one CBA did not. There is very low-quality evidence that implementation of stricter legislation can reduce noise levels in workplaces. Controlled studies of other engineering control interventions in the field have not been conducted. There is moderate-quality evidence that training of proper insertion of earplugs significantly reduces noise exposure at short-term follow-up but long-term follow-up is still needed.There is very low-quality evidence that the better use of hearing protection devices as part of HLPPs reduces the risk of hearing loss, whereas for other programme components of HLPPs we did not find such an effect. The absence of conclusive evidence should not be interpreted as evidence of lack of effectiveness. Rather, it means that further research is very likely to have an important impact.

42 CFR 37.10 - Standards incorporated by reference.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Department, Medical Physics Publishing, 4513 Vernon Blvd., Madison, WI 53705, http://www.aapm.org/pubs... Automatic Exposure Control Devices, published by the American Institute of Physics for AAPM, January 1985... Institute of Physics, July 1990, into § 37.44(g). (4) AAPM Report No. 74, Quality Control in Diagnostic...

42 CFR 37.10 - Standards incorporated by reference.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Department, Medical Physics Publishing, 4513 Vernon Blvd., Madison, WI 53705, http://www.aapm.org/pubs... Automatic Exposure Control Devices, published by the American Institute of Physics for AAPM, January 1985... Institute of Physics, July 1990, into § 37.44(g). (4) AAPM Report No. 74, Quality Control in Diagnostic...

Real time chemical exposure and risk monitor

DOEpatents

Thrall, Karla D.; Kenny, Donald V.; Endres, George W. R.; Sisk, Daniel R.

1997-01-01

The apparatus of the present invention is a combination of a breath interface and an external exposure dosimeter interface to a chemical analysis device, all controlled by an electronic processor for quantitatively analyzing chemical analysis data from both the breath interface and the external exposure dosimeter for determining internal tissue dose. The method of the present invention is a combination of steps of measuring an external dose, measuring breath content, then analyzing the external dose and breath content and determining internal tissue dose.

Real time chemical exposure and risk monitor

DOEpatents

Thrall, K.D.; Kenny, D.V.; Endres, G.W.R.; Sisk, D.R.

1997-07-08

The apparatus of the present invention is a combination of a breath interface and an external exposure dosimeter interface to a chemical analysis device, all controlled by an electronic processor for quantitatively analyzing chemical analysis data from both the breath interface and the external exposure dosimeter for determining internal tissue dose. The method of the present invention is a combination of steps of measuring an external dose, measuring breath content, then analyzing the external dose and breath content and determining internal tissue dose. 7 figs.

Anti-vibration gloves?

PubMed

Hewitt, Sue; Dong, Ren G; Welcome, Daniel E; McDowell, Thomas W

2015-03-01

For exposure to hand-transmitted vibration (HTV), personal protective equipment is sold in the form of anti-vibration (AV) gloves, but it remains unclear how much these gloves actually reduce vibration exposure or prevent the development of hand-arm vibration syndrome in the workplace. This commentary describes some of the issues that surround the classification of AV gloves, the assessment of their effectiveness and their applicability in the workplace. The available information shows that AV gloves are unreliable as devices for controlling HTV exposures. Other means of vibration control, such as using alternative production techniques, low-vibration machinery, routine preventative maintenance regimes, and controlling exposure durations are far more likely to deliver effective vibration reductions and should be implemented. Furthermore, AV gloves may introduce some adverse effects such as increasing grip force and reducing manual dexterity. Therefore, one should balance the benefits of AV gloves and their potential adverse effects if their use is considered. © Crown copyright 2014.

Controllable Growth of Perovskite Films by Room-Temperature Air Exposure for Efficient Planar Heterojunction Photovoltaic Cells.

PubMed

Yang, Bin; Dyck, Ondrej; Poplawsky, Jonathan; Keum, Jong; Das, Sanjib; Puretzky, Alexander; Aytug, Tolga; Joshi, Pooran C; Rouleau, Christopher M; Duscher, Gerd; Geohegan, David B; Xiao, Kai

2015-12-01

A two-step solution processing approach has been established to grow void-free perovskite films for low-cost high-performance planar heterojunction photovoltaic devices. A high-temperature thermal annealing treatment was applied to drive the diffusion of CH3NH3I precursor molecules into a compact PbI2 layer to form perovskite films. However, thermal annealing for extended periods led to degraded device performance owing to the defects generated by decomposition of perovskite into PbI2. A controllable layer-by-layer spin-coating method was used to grow "bilayer" CH3NH3I/PbI2 films, and then drive the interdiffusion between PbI2 and CH3NH3I layers by a simple air exposure at room temperature for making well-oriented, highly crystalline perovskite films without thermal annealing. This high degree of crystallinity resulted in a carrier diffusion length of ca. 800 nm and a high device efficiency of 15.6%, which is comparable to values reported for thermally annealed perovskite films. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ecological Momentary Assessment of the Association Between Exposure to Alcohol Advertising and Early Adolescents' Beliefs About Alcohol

PubMed Central

Martino, Steven C.; Kovalchik, Stephanie A.; Collins, Rebecca L.; Becker, Kirsten M.; Shadel, William G.; D'Amico, Elizabeth J.

2015-01-01

Purpose To evaluate the momentary association between exposure to alcohol advertising and middle school students' beliefs about alcohol in real-world settings and to explore racial/ethnic differences in this association. Methods Middle school students (N = 588) carried handheld data collection devices for 14 days, recording their exposures to all forms of alcohol advertising during the assessment period. Students also responded to three investigator-initiated control prompts (programmed to occur randomly) on each day of the assessment period. After each exposure to advertising and at each control prompt, students reported their beliefs about alcohol. Mixed effects regression models compared students' beliefs about alcohol between moments of exposure to alcohol advertising and control prompts. Results Students perceived the typical person their age who drinks alcohol (prototype perceptions) more favorably and perceived alcohol use as more normative at times of exposure to alcohol advertising than at times of non-exposure (i.e., at control prompts). Exposure to alcohol advertising was not associated with shifts in the perceived norms of Black and Hispanic students, however, and the association between exposure and prototype perceptions was stronger among non-Hispanic students than among Hispanic students. Conclusions Exposure to alcohol advertising is associated with acute shifts in adolescents' perceptions of the typical person that drinks alcohol and the normativeness of drinking. These associations are both statistically and substantively meaningful. PMID:26480846

A Tunable, Biodegradable, Thin-Film Polymer Device as a Long-Acting Implant Delivering Tenofovir Alafenamide Fumarate for HIV Pre-exposure Prophylaxis

PubMed Central

Schlesinger, Erica; Johengen, Daniel; Luecke, Ellen; Rothrock, Ginger; McGowan, Ian; van der Straten, Ariane; Desai, Tejal

2016-01-01

Purpose The effectiveness of Tenofovir based HIV pre-exposure prophylaxis (PrEP) is proven, but hinges on correct and consistent use. User compliance and therapeutic effectiveness can be improved by long acting drug delivery systems. Here we describe a thin-film polymer device (TFPD) as a biodegradable subcutaneous implant for PrEP. Methods A thin-film polycaprolactone (PCL) membrane controls drug release from a reservoir. To achieve membrane controlled release, TAF requires a formulation excipient such as PEG300 to increase the dissolution rate and reservoir solubility. Short-term In vitro release studies are used to develop an empirical design model, which is applied to the production of in vitro prototype devices demonstrating up to 90-days of linear release and TAF chemical stability. Results The size and shape of the TFPD are tunable, achieving release rates ranging from 0.5–4.4 mg/day in devices no larger than a contraceptive implant. Based on published data for oral TAF, subcutaneous constant-rate release for HIV PrEP is estimated at < 2.8mg/day. Prototype devices demonstrated linear release at 1.2mg/day for up to 90 days and at 2.2mg/day for up to 60 days. Conclusions We present a biodegradable TFPD for subcutaneous delivery of TAF for HIV PrEP. The size, shape and release rate of the device are tunable over a > 8-fold range. PMID:26975357

Initial contamination control considerations for the Next Generation Space Telescope (NGST)

NASA Technical Reports Server (NTRS)

Wooldridge, Eve M.

1997-01-01

The NASA's Next Generation Space Telescope (NGST), a 6 m to 8 m diameter device, is described. The NGST will be radiatively cooled to 30 K to 60 K in order to carry out extremely deep exposures at near infrared wavelengths, for 5 years to 10 years lifetime. Initial contamination control design options include strict materials selection and baking out of both hardware down to the component level, minimizing or eliminating the exposure to the optical telescope assembly to sunlight or earth albedo during deployment and early in-orbit operations.

Development of a dose-controlled multiculture cell exposure chamber for efficient delivery of airborne and engineered nanoparticles

NASA Astrophysics Data System (ADS)

Asimakopoulou, Akrivi; Daskalos, Emmanouil; Lewinski, Nastassja; Riediker, Michael; Papaioannou, Eleni; Konstandopoulos, Athanasios G.

2013-04-01

In order to study the various health influencing parameters related to engineered nanoparticles as well as to soot emitted by Diesel engines, there is an urgent need for appropriate sampling devices and methods for cell exposure studies that simulate the respiratory system and facilitate associated biological and toxicological tests. The objective of the present work was the further advancement of a Multiculture Exposure Chamber (MEC) into a dose-controlled system for efficient delivery of nanoparticles to cells. It was validated with various types of nanoparticles (Diesel engine soot aggregates, engineered nanoparticles for various applications) and with state-of-the-art nanoparticle measurement instrumentation to assess the local deposition of nanoparticles on the cell cultures. The dose of nanoparticles to which cell cultures are being exposed was evaluated in the normal operation of the in vitro cell culture exposure chamber based on measurements of the size specific nanoparticle collection efficiency of a cell free device. The average efficiency in delivering nanoparticles in the MEC was approximately 82%. The nanoparticle deposition was demonstrated by Transmission Electron Microscopy (TEM). Analysis and design of the MEC employs Computational Fluid Dynamics (CFD) and true to geometry representations of nanoparticles with the aim to assess the uniformity of nanoparticle deposition among the culture wells. Final testing of the dose-controlled cell exposure system was performed by exposing A549 lung cell cultures to fluorescently labeled nanoparticles. Delivery of aerosolized nanoparticles was demonstrated by visualization of the nanoparticle fluorescence in the cell cultures following exposure. Also monitored was the potential of the aerosolized nanoparticles to generate reactive oxygen species (ROS) (e.g. free radicals and peroxides generation), thus expressing the oxidative stress of the cells which can cause extensive cellular damage or damage on DNA.

Effect of an electronic control device exposure on a methamphetamine-intoxicated animal model.

PubMed

Dawes, Donald M; Ho, Jeffrey D; Cole, Jon B; Reardon, Robert F; Lundin, Erik J; Terwey, Karen S; Falvey, Dan G; Miner, James R

2010-04-01

Because of the prevalence of methamphetamine abuse worldwide, it is not uncommon for subjects in law enforcement encounters to be methamphetamine-intoxicated. Methamphetamine has been present in arrest-related death cases in which an electronic control device (ECD) was used. The primary purpose of this study was to determine the cardiac effects of an ECD in a methamphetamine intoxication model. Sixteen anesthetized Dorset sheep (26-78 kg) received 0.0 mg/kg (control animals, n = 4), 0.5 mg/kg (n = 4), 1.0 mg/kg (n = 4), or 1.5 mg/kg (n = 4) of methamphetamine hydrochloride as a slow intravenous (IV) bolus during continuous cardiac monitoring. The animals received the following exposures in sequence from a TASER X26 ECD beginning at 30 minutes after the administration of the drug: 1) 5-second continuous exposure, 2) 15-second intermittent exposure, 3) 30-second intermittent exposure, and 4) 40-second intermittent exposure. Darts were inserted at the sternal notch and the cardiac apex, to a depth of 9 mm. Cardiac motion was determined by thoracotomy (smaller animals, < or = 32 kg) or echocardiography (larger animals, > 68 kg). Data were analyzed using descriptive statistics and chi-square tests. Animals given methamphetamine demonstrated signs of methamphetamine toxicity with tachycardia, hypertension, and atrial and ventricular ectopy in the 30-minute period immediately after administration of the drug. Smaller animals (n = 8, < or = 32 kg, mean = 29.4 kg) had supraventricular dysrhythmias immediately after the ECD exposures. Larger animals (n = 8, > 68 kg, mean = 72.4) had only sinus tachycardia after the exposures. One of the smaller animals had frequent episodes of ventricular ectopy after two exposures, including runs of delayed onset, nonsustained six- to eight-beat unifocal and multifocal ventricular tachycardia that spontaneously resolved. This animal had significant ectopy prior to the exposures as well. Thoracotomy performed on three smaller animals demonstrated cardiac capture during ECD exposure consistent with previous animal studies. In the larger animals, none of the methamphetamine-intoxicated animals demonstrated cardiac capture. Two control sheep showed evidence of capture similar to the smaller animals. No ventricular fibrillation occurred after the exposure in any animal. In smaller animals (32 kg or less), ECD exposure exacerbated atrial and ventricular irritability induced by methamphetamine intoxication, but this effect was not seen in larger, adult-sized animals. There were no episodes of ventricular fibrillation after exposure associated with ECD exposure in methamphetamine-intoxicated sheep.

SU-F-T-505: A Novel Approach for Sparing Critical Organs at Risk for Cancer Patients Undergoing Radiation Oncology Treatments

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

Lavvafi, H; Pourriahi, M; Elahinia, H

2016-06-15

Purpose: A major goal of an effective radiation treatment plan is to deliver the maximum dose to the tumor while minimizing radiation exposure to the surrounding normal structures. For example, due to the radiation exposure to neighboring critical structures during prostate cancer treatment, a significant increase in cancer risk was observed for the bladder (77%) and the rectum (105%) over the following decade. Consequently, an effective treatment plan necessitates limiting the exposure to such organs which can best be achieved by physically displacing the organ at-risk. The goal of this study is to present a prototype for an organ re-positionermore » device designed and fabricated to physically move the rectum away from the path of radiation beam during external beam and brachytherapy treatments. This device affords patient comfort and provides a fully controlled motion to safely relocate the rectum during treatment. Methods: The NiTi shape memory alloy was designed and optimized for manufacturing a rectal re-positioner device through cooling and heating the core alloy for its shaping. This has been achieved through a prototyped custom designed electronic circuit in order to induce the reversible austenitic transformation and was tested rigorously to ensure the integrity of the actuated motion in displacement of the target anatomy. Results: The desirable NiTi shape-setting was configured for easy insertion and based on anatomical constraint. When the final prototype was evaluated, accuracy and precision of the maximum displacement and temperature changes revealed that the device could safely be used within the target anatomy. Conclusion: The organ re-positioner device is a promising tool that can be implemented in clinical setting. It provides a controlled and safe displacement of the delicate organ(s) at risk. The location of the organ being treated could also be identified using conventional onboard imaging devices or MV imaging available on-board most modern clinical accelerators.« less

Ion-beam treatment to prepare surfaces of p-CdTe films

DOEpatents

Gessert, Timothy A.

2001-01-01

A method of making a low-resistance electrical contact between a p-CdTe layer and outer contact layers by ion beam processing comprising: a) placing a CdS/CdTe device into a chamber and evacuating the chamber; b) orienting the p-CdTe side of the CdS/CdTe layer so that it faces apparatus capable of generating Ar atoms and ions of preferred energy and directionality; c) introducing Ar and igniting the area of apparatus capable of generating Ar atoms and ions of preferred energy and directionality in a manner so that during ion exposure, the source-to-substrate distance is maintained such that it is less than the mean-free path or diffusion length of the Ar atoms and ions at the vacuum pressure; d) allowing exposure of the p-CdTe side of the device to said ion beam for a period less than about 5 minutes; and e) imparting movement to the substrate to control the real uniformity of the ion-beam exposure on the p-CdTe side of the device.

Biological processes, quantum mechanics and electromagnetic fields: the possibility of device-encapsulated human intention in medical therapies.

PubMed

Kohane, M J; Tiller, W A

2001-06-01

The general hypothesis that quantum mechanics (QM) and thermodynamic concepts relate to biological systems is discussed and applied to the biological influence of: (1) electromagnetic fields (EMFs); and (2) EMFs that have been exposed to human intention. We illustrate our hypothesis with experiments involving four simultaneous treatments: exposure to ambient EMFs in the laboratory environment (C), exposure in a Faraday cage (F) and exposure in a Faraday cage with either: (i) an electronic device (IIED) which had been exposed to a specific human intention (d,j); or (ii) a non-exposed, physically identical, device (d,o). Experimental systems were fitness and energy metabolism in Drosophila melanogaster, in vitro enzyme activity and molecular concentration variability over time. Results indicated that shielding from ambient EMFs via a Faraday cage (F) made a significant difference relative to the unshielded control (C). Further, (d,o) had a significant lowering effect in the shielded environment. Finally, there was a strong 'intention' effect with the IIED (d,j) producing significant and positive effects in comparison to (d,o) in each experimental system. Copyright 2001 Harcourt Publishers Ltd.

Using a mathematical model to evaluate the efficacy of TB control measures.

PubMed Central

Gammaitoni, L.; Nucci, M. C.

1997-01-01

We evaluated the efficacy of recommended tuberculosis (TB) infection control measures by using a deterministic mathematical model for airborne contagion. We examined the percentage of purified protein derivative conversions under various exposure conditions, environmental controlstrategies, and respiratory protective devices. We conclude that environmental control cannot eliminate the risk for TB transmission during high-risk procedures; respiratory protective devices, and particularly high-efficiency particulate air masks, may provide nearly complete protection if used with air filtration or ultraviolet irradiation. Nevertheless, the efficiency of these control measures decreases as the infectivity of the source case increases. Therefore, administrative control measures (e.g., indentifying and isolating patients with infectious TB) are the most effective because they substantially reduce the rate of infection. PMID:9284378

Ecological Momentary Assessment of the Association Between Exposure to Alcohol Advertising and Early Adolescents' Beliefs About Alcohol.

PubMed

Martino, Steven C; Kovalchik, Stephanie A; Collins, Rebecca L; Becker, Kirsten M; Shadel, William G; D'Amico, Elizabeth J

2016-01-01

To evaluate the momentary association between exposure to alcohol advertising and middle-school students' beliefs about alcohol in real-world settings and to explore racial/ethnic differences in this association. Middle-school students (N = 588) carried handheld data collection devices for 14 days, recording their exposures to all forms of alcohol advertising during the assessment period. Students also responded to three investigator-initiated control prompts (programmed to occur randomly) on each day of the assessment period. After each exposure to advertising and at each control prompt, students reported their beliefs about alcohol. Mixed-effects regression models compared students' beliefs about alcohol between moments of exposure to alcohol advertising and control prompts. Students perceived the typical person their age who drinks alcohol (prototype perceptions) more favorably and perceived alcohol use as more normative at times of exposure to alcohol advertising than at times of nonexposure (i.e., at control prompts). Exposure to alcohol advertising was not associated with shifts in the perceived norms of black and Hispanic students, however, and the association between exposure and prototype perceptions was stronger among non-Hispanic students than among Hispanic students. Exposure to alcohol advertising is associated with acute shifts in adolescents' perceptions of the typical person that drinks alcohol and the normativeness of drinking. These associations are both statistically and substantively meaningful. Copyright © 2016 Society for Adolescent Health and Medicine. All rights reserved.

Automatic brightness control of laser spot vision inspection system

NASA Astrophysics Data System (ADS)

Han, Yang; Zhang, Zhaoxia; Chen, Xiaodong; Yu, Daoyin

2009-10-01

The laser spot detection system aims to locate the center of the laser spot after long-distance transmission. The accuracy of positioning laser spot center depends very much on the system's ability to control brightness. In this paper, an automatic brightness control system with high-performance is designed using the device of FPGA. The brightness is controlled by combination of auto aperture (video driver) and adaptive exposure algorithm, and clear images with proper exposure are obtained under different conditions of illumination. Automatic brightness control system creates favorable conditions for positioning of the laser spot center later, and experiment results illuminate the measurement accuracy of the system has been effectively guaranteed. The average error of the spot center is within 0.5mm.

A laboratory evaluation of four quality control devices for radiographic processing.

PubMed

Rushton, V E; Horner, K

1994-08-01

Quality assurance programmes for radiographic processing traditionally employ expensive sensitometric and densitometric techniques. However cheap and simple devices for monitoring radiographic processing are available. The aim of this study was to make a comparison of four such devices in terms of their ability to detect variations in radiographic density of clinical significance. Three of the devices are commercially available while the fourth is easily manufactured from waste materials. Ideal bitewing exposure times were selected for four different kilovoltage/film speed combinations. Phantom bitewing radiographs, exposed using these exposure times, were processed using a variety of times and developer temperatures to simulate variations in radiographic quality due to inadequate processing conditions. Test films, produced using the four monitoring devices, were exposed and processed under identical conditions. The phantom bitewings were judged to have 'acceptable' quality when the optical density of that part of the film not showing calcified structures was within +/- 0.5 of that of the film processed under optimal conditions. The efficacy of the monitoring devices in indicating the adequacy of processing was assessed by a comparison of their readings with those made from the phantom bitewings. None of the monitoring devices was ideal for all the kilovoltage/film speed combinations tested, but the homemade device proved to be the most generally effective. We conclude that guidelines to dentists on radiographic quality assurance should include reference to and details of this simple device.

Recovery of damage in rad-hard MOS devices during and after irradiation by electrons, protons, alphas, and gamma rays

NASA Technical Reports Server (NTRS)

Brucker, G. J.; Van Gunten, O.; Stassinopoulos, E. G.; Shapiro, P.; August, L. S.; Jordan, T. M.

1983-01-01

This paper reports on the recovery properties of rad-hard MOS devices during and after irradiation by electrons, protons, alphas, and gamma rays. The results indicated that complex recovery properties controlled the damage sensitivities of the tested parts. The results also indicated that damage sensitivities depended on dose rate, total dose, supply bias, gate bias, transistor type, radiation source, and particle energy. The complex nature of these dependencies make interpretation of LSI device performance in space (exposure to entire electron and proton spectra) difficult, if not impossible, without respective ground tests and analyses. Complete recovery of n-channel shifts was observed, in some cases within hours after irradiation, with equilibrium values of threshold voltages greater than their pre-irradiation values. This effect depended on total dose, radiation source, and gate bias during exposure. In contrast, the p-channel shifts recovered only 20 percent within 30 days after irradiation.

An evaluation of retrofit engineering control interventions to reduce perchloroethylene exposures in commercial dry-cleaning shops.

PubMed

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 maintenance of the engineering controls, this study showed that retrofitting engineering controls may be a feasible option for some dry-cleaning shop owners to reduce worker exposures to perchloroethylene. By installing retrofit controls, a dry-cleaning facility can reduce exposures, in some cases dramatically, and bring operators into compliance with the Occupational Safety and Health Administration (OSHA) peak exposure limit of 300 ppm. Retrofit engineering controls are also likely to enable many dry-cleaning workers to lower their overall personal TWA exposures to perchloroethylene.

Five years experience with a new intraoral maxillary distraction device (RID).

PubMed

Picard, Arnaud; Diner, Patrick A; Galliani, Eva; Tomat, Catherine; Vazquez, Ma rie Paule; Carls, Friedrich P

2011-10-01

Maxillary distraction osteogenesis is well established for the treatment of severe retromaxilla. We report our experience since 2004 of the treatment of 19 patients using a new intraoral maxillary distraction device. Maxillary advancement was successful in all patients with mean advancement of 9.6mm (range 4-17) measured at a point in lateral cephalograms. The new device limited surgical exposure and the amount of materials implanted, and improved control in every phase of the distraction. It was psychologically accepted by patients and was more comfortable than existing devices. Copyright © 2010 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Postural changes following sensory reinterpretation as an analog to spaceflight

NASA Technical Reports Server (NTRS)

Paloski, William H.; Harm, D. L.; Reschke, M. F.; Doxey, D. D.; Skinner, N. C.; Michaud, L. J.; Parker, D. E.

1990-01-01

Postural control changes noted in astronauts immediately following spaceflight are thought to be caused by inflight adaptative changes in Central Nervous System (CNS) processing of sensory information from the visual, vestibular, and proprioceptive systems. In order to elicit these adaptative changes in ground based studies, a Tilt Translation Device (TTD) which causes the CNS of exposed subjects to reinterpret tilt generated sensory inputs from the otolith organs as linear translation of the subject was developed. This device was designed to simulate partially the stimulus rearrangement experienced by astronauts during microgravity. Postural stability is assessed in ten subjects before and after 30 minutes of exposure to TTD. The resulting data suggests that exposure to TTD causes decreases in postural stability and shifts in postflight studies of astronauts. It is concluded that the TTD may be an effective weightlessness simulator, and that the postural changes following TTD exposure may provide a useful dependent measure for evaluation of this apparatus.

High brightness--multiple beamlets source for patterned X-ray production

DOEpatents

Leung, Ka-Ngo [Hercules, CA; Ji, Qing [Albany, CA; Barletta, William A [Oakland, CA; Jiang, Ximan [El Cerrito, CA; Ji, Lili [Albany, CA

2009-10-27

Techniques for controllably directing beamlets to a target substrate are disclosed. The beamlets may be either positive ions or electrons. It has been shown that beamlets may be produced with a diameter of 1 .mu.m, with inter-aperture spacings of 12 .mu.m. An array of such beamlets, may be used for maskless lithography. By step-wise movement of the beamlets relative to the target substrate, individual devices may be directly e-beam written. Ion beams may be directly written as well. Due to the high brightness of the beamlets from extraction from a multicusp source, exposure times for lithographic exposure are thought to be minimized. Alternatively, the beamlets may be electrons striking a high Z material for X-ray production, thereafter collimated to provide patterned X-ray exposures such as those used in CAT scans. Such a device may be used for remote detection of explosives.

Fentanyl Iontophoretic Transdermal System (IONSYS(®)) can be Safely used in the Hospital Environment with X-Rays, Computerized Tomography and Radiofrequency Identification Devices.

PubMed

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 supported financially by The Medicines Company.

Electromagnetic fields used clinically to improve bone healing also impact lymphocyte proliferation in vitro.

PubMed

Johnson, M T; Vanscoy-Cornett, A; Vesper, D N; Swez, J A; Chamberlain, J K; Seaward, M B; Nindl, G

2001-01-01

An important aspect of medical device development is the need to understand how a device produces a specific biological effect. The focus can then be on optimizing that effect by device modification and repeated testing. Several reports from this lab have targeted programmed cell death, or apoptosis, as a cellular pathway that is induced by exposure of transformed leukemic T-cells in culture to specific frequency and intensity electromagnetic fields (EMFs). An EMF delivery device capable of selectively inducing T-cell apoptosis in human tissues could be used to enhance healing by limiting the production of molecules that promote inflammatory disorders such as psoriasis and tendonitis. In the present study, we examined the normal T-cell response to EMF exposure in vitro. In the peripheral blood, 70-80% of the lymphocytes are T-cells, and thus is a rich source of normal cells that match the transformed T-cells used in other experiments (Jurkat cells). We isolated lymphocytes from the peripheral blood of humans and rats, cultured them in nutritive medium and exposed them to either a complex 1.8 mT pulsed EMF (Electrobiology, Inc.), a 0.1 mT, 60 Hz power frequency EMF or a 0.2 mT, 100 Hz sinusoidal EMF. Control lymphocytes were cultured similarly, without field exposure. Lymphocytes were then treated with T-cell mitogens and evaluated for proliferative capacity after an additional 72 hours culture. Results indicate that T-cell proliferation is modulated by in vitro exposure to defined EMFs. The potential use of an EMF delivery device capable of selectively inducing such T-cell effects is discussed.

Allethrin-Based Mosquito Control Device Causing Knockdown, Morbidity, and Mortality in Four Species of Field-Caught Mosquitoes (Diptera: Culicidae).

PubMed

Bibbs, Christopher S; Fulcher, Ali; Xue, Rui-De

2015-07-01

A mosquito control device marketed for spatial repellency, the ThermaCELL Mosquito Repellent Appliance, was evaluated in semifield trials against multiple field-caught species of mosquito. Using paper and mesh cages, mosquito test groups of at least 30 mosquitoes were suspended in a 2,337 cubic foot outdoor space while two ThermaCELL repellent devices were active. After 30 min of treatment, cages were moved to the laboratory to observe knockdown, morbidity, and mortality for 24 h. Species tested included Aedes atlanticus Dyar and Knab (98% average mortality), Psorophora ferox Humboldt (97% average mortality), Psorophora columbiae Dyar and Knab (96% average mortality), and Aedes taeniorhynchus Wiedemann (84% average mortality). The repellent devices showed effectiveness with high knockdown and mortality across all species tested. Mosquito control devices like the ThermaCELL Mosquito Repellent Appliance may have further practical applications to help combat viral exposures by limiting host mosquitoes. Such devices may provide a functional alternative to DEET dependence in the current state of mosquito management. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Light exposure via a head-mounted device suppresses melatonin and improves vigilant attention without affecting cortisol and comfort.

PubMed

Schmidt, Christina; Xhrouet, Marine; Hamacher, Manon; Delloye, Eric; LeGoff, Caroline; Cavalier, Etienne; Collette, Fabienne; Vandewalle, Gilles

2018-06-26

We aimed at assessing whether a head-mounted light therapy device, enriched in blue wavelengths, suppresses melatonin secretion and improves vigilant attention in the late evening hours. We also assessed whether using such light device is associated with discomfort and physiological stress. Seventeen healthy young participants (eight females) participated in a counterbalanced within-subject design during which they were exposed for 2 hr before habitual sleep time to a blue-enriched light (1500 lx) or to a lower intensity red-light (150 lx) control condition, using a new-generation light emitting diode (LED) head-mounted device. Compared to the red light control condition, blue-enriched light significantly reduced melatonin secretion and reaction times during a psychomotor vigilance task while no significant differences were detected in discomfort and cortisol levels. These results suggest that, compared to a control condition, blue-enriched light, delivered by a new-generation head-mounted device, elicits typical non-visual responses to light without detectable discomfort and physiological stress. They suggest that such devices might constitute an effective alternative to standard light boxes. © 2018 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

21 CFR 892.1715 - Full-field digital mammography system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... planar digital x-ray images of the entire breast. This generic type of device may include digital mammography acquisition software, full-field digital image receptor, acquisition workstation, automatic exposure control, image processing and reconstruction programs, patient and equipment supports, component...

21 CFR 892.1715 - Full-field digital mammography system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... planar digital x-ray images of the entire breast. This generic type of device may include digital mammography acquisition software, full-field digital image receptor, acquisition workstation, automatic exposure control, image processing and reconstruction programs, patient and equipment supports, component...

21 CFR 892.1715 - Full-field digital mammography system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... planar digital x-ray images of the entire breast. This generic type of device may include digital mammography acquisition software, full-field digital image receptor, acquisition workstation, automatic exposure control, image processing and reconstruction programs, patient and equipment supports, component...

21 CFR 892.1715 - Full-field digital mammography system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... planar digital x-ray images of the entire breast. This generic type of device may include digital mammography acquisition software, full-field digital image receptor, acquisition workstation, automatic exposure control, image processing and reconstruction programs, patient and equipment supports, component...

Use of and Occupational Exposure to Indium in the United States

PubMed Central

Hines, Cynthia J.; Roberts, Jennifer L.; Andrews, Ronnee N.; Jackson, Matthew V.; Deddens, James A.

2015-01-01

Indium use has increased greatly in the past decade in parallel with the growth of flat-panel displays, touchscreens, optoelectronic devices, and photovoltaic cells. Much of this growth has been in the use of indium tin oxide (ITO). This increased use has resulted in more frequent and intense exposure of workers to indium. Starting with case reports and followed by epidemiological studies, exposure to ITO has been linked to serious and sometimes fatal lung disease in workers. Much of this research was conducted in facilities that process sintered ITO, including manufacture, grinding, and indium reclamation from waste material. Little has been known about indium exposure to workers in downstream applications. In 2009–2011, the National Institute for Occupational Safety and Health (NIOSH) contacted 89 potential indium-using companies; 65 (73%) responded, and 43 of the 65 responders used an indium material. Our objective was to identify current workplace applications of indium materials, tasks with potential indium exposure, and exposure controls being used. Air sampling for indium was either conducted by NIOSH or companies provided their data for a total of 63 air samples (41 personal, 22 area) across 10 companies. Indium exposure exceeded the NIOSH recommended exposure limit (REL) of 0.1 mg/m3 for certain methods of resurfacing ITO sputter targets, cleaning sputter chamber interiors, and in manufacturing some inorganic indium compounds. Indium air concentrations were low in sputter target bonding with indium solder, backside thinning and polishing of fabricated indium phosphide-based semiconductor devices, metal alloy production, and in making indium-based solder pastes. Exposure controls such as containment, local exhaust ventilation (LEV), and tool-mounted LEV can be effective at reducing exposure. In conclusion, occupational hygienists should be aware that the manufacture and use of indium materials can result in indium air concentrations that exceed the NIOSH REL. Given recent findings of adverse health effects in workers, research is needed to determine if the current REL sufficiently protects workers against indium-related diseases. PMID:24195539

The leaded apron revisited: does it reduce gonadal radiation dose in dental radiology?

PubMed

Wood, R E; Harris, A M; van der Merwe, E J; Nortjé, C J

1991-05-01

A tissue-equivalent anthropomorphic human phantom was used with a lithium fluoride thermoluminescent dosimetry system to evaluate the radiation absorbed dose to the ovarian and testicular region during dental radiologic procedures. Measurements were made with and without personal lead shielding devices consisting of thyroid collar and apron of 0.25 mm lead thickness equivalence. The radiation absorbed dose with or without lead shielding did not differ significantly from control dosimeters in vertex occlusal and periapical views (p greater than 0.05). Personal lead shielding devices did reduce gonadal dose in the case of accidental exposure (p less than 0.05). A leaded apron of 0.25 mm lead thickness equivalent was permeable to radiation in direct exposure testing.

Test and evaluation of constant-flow devices for use in SSN AFFF proportioning systems. Interim report, January-May 1986

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

Williams, F.W.; Back, G.G.; Burns, R.E.

1986-11-04

Constant flow devices, which deliver a constant flow of liquid over a range of upstream and downstream pressures, have been suggested as an alternative to orifice plates for proportioning AFFF in SSN 21 fire-suppression systems. Operational and performance characteristics of two lightweight, inexpensive, commercially available constant-flow devices have significant advantages over orifice plates. Both models tested, however, showed performance degradation when subjected to simulated service conditions. A constant flow device with improved resistance to wear and to AFFF exposure is desirable. Since the constant-flow control devices tested improves proportioning efficiency but do not have optimum characteristics, investigation of improved devicesmore » or methods is recommended.« less

'Toy' laser macular burns in children: 12-month update.

PubMed

Raoof, N; O'Hagan, J; Pawlowska, N; Quhill, F

2016-03-01

There is increasing evidence that high-powered hand-held laser devices cause retinal injury. We present 12-month follow-up data for three patients that we previously reported with such retinal injuries. A retrospective case series of three children with maculopathy secondary to exposure to high-power hand-held laser devices. All children underwent clinical examination and spectral domain optical coherence tomography (SD-OCT) at presentation and follow-up. Fundus-controlled microperimetry was also undertaken 12-19 months after exposure. Three children sustained macular injury after exposure to a high-powered hand-held laser. Acutely, they presented with a 'vitelliform-like' maculopathy with reduced vision. Over the course of follow-up, the best corrected Snellen acuity in all three patients improved to 'normal' levels (range 6/6-6/9). Long-term deficits in foveal retinal sensitivity were identified in two patients using fundus-controlled microperimetry. SD-OCT imaging showed persistent disruption of the foveal outer photoreceptor layers in all three children. Although visual acuity improved over time, deficits in microperimetry and SD-OCT persisted. All three children had retinal pigment epithelium changes, requiring follow-up for longer-term sequelae of laser injuries such as expansion of retinal atrophy and development of choroidal neovascular membranes.

EVALUATION OF AIR PURIFICATION DEVICES FOR CONTROL OF INDOOR PM

EPA Science Inventory

Because people spend most of their time indoors (89%), the indoor environment is a primary determinant of particle exposure. The indoor environment is especially an important determinant for the very young, the very old, and those with underlying cardiopulmonary disease because...

Low-Cost, Rapidly Responsive, Controllable, and Reversible Photochromic Hydrogel for Display and Storage.

PubMed

Yang, Yongqi; Guan, Lin; Gao, Guanghui

2018-04-25

Traditional optoelectronic devices without stretchable performance could be limited for substrates with irregular shape. Therefore, it is urgent to explore a new generation of flexible, stretchable, and low-cost intelligent vehicles as visual display and storage devices, such as hydrogels. In the investigation, a novel photochromic hydrogel was developed by introducing the negatively charged ammonium molybdate as a photochromic unit into polyacrylamide via ionic and covalent cross-linking. The hydrogel exhibited excellent properties of low cost, easy preparation, stretchable deformation, fatigue resistance, high transparency, and second-order response to external signals. Moreover, the photochromic and fading process of hydrogels could be precisely controlled and repeated under the irradiation of UV light and exposure of oxygen at different time and temperature. The photochromic hydrogel could be considered applied for artificial intelligence system, wearable healthcare device, and flexible memory device. Therefore, the strategy for designing a soft photochromic material would open a new direction to manufacture flexible and stretchable devices.

Selectively-etched nanochannel electrophoretic and electrochemical devices

DOEpatents

Surh, Michael P.; Wilson, William D.; Barbee, Jr., Troy W.; Lane, Stephen M.

2004-11-16

Nanochannel electrophoretic and electrochemical devices having selectively-etched nanolaminates located in the fluid transport channel. The normally flat surfaces of the nanolaminate having exposed conductive (metal) stripes are selectively-etched to form trenches and baffles. The modifications of the prior utilized flat exposed surfaces increase the amount of exposed metal to facilitate electrochemical redox reaction or control the exposure of the metal surfaces to analytes of large size. These etched areas variously increase the sensitivity of electrochemical detection devices to low concentrations of analyte, improve the plug flow characteristic of the channel, and allow additional discrimination of the colloidal particles during cyclic voltammetry.

Selectively-etched nanochannel electrophoretic and electrochemical devices

DOEpatents

Surh, Michael P [Livermore, CA; Wilson, William D [Pleasanton, CA; Barbee, Jr., Troy W.; Lane, Stephen M [Oakland, CA

2006-06-27

Nanochannel electrophoretic and electrochemical devices having selectively-etched nanolaminates located in the fluid transport channel. The normally flat surfaces of the nanolaminate having exposed conductive (metal) stripes are selectively-etched to form trenches and baffles. The modifications of the prior utilized flat exposed surfaces increase the amount of exposed metal to facilitate electrochemical redox reaction or control the exposure of the metal surfaces to analytes of large size. These etched areas variously increase the sensitivity of electrochemical detection devices to low concentrations of analyte, improve the plug flow characteristic of the channel, and allow additional discrimination of the colloidal particles during cyclic voltammetry.

Exposure assessment for a nested case-control study of lung cancer among European asphalt workers.

PubMed

Agostini, Michela; Ferro, Gilles; Olsson, Ann; Burstyn, Igor; De Vocht, Frank; Hansen, Johnni; Lassen, Christina Funch; Johansen, Christoffer; Kjaerheim, Kristina; Langard, Sverre; Stucker, Isabelle; Ahrens, Wolfgang; Behrens, Thomas; Lindbohm, Marja-Liisa; Heikkilä, Pirjo; Heederik, Dick; Portengen, Lützen; Shaham, Judith; Boffetta, Paolo; Kromhout, Hans

2010-10-01

Development of a method for retrospective assessment of exposure to bitumen fume, bitumen condensate, organic vapour, polycyclic aromatic hydrocarbons, and co-exposures to known or suspected lung carcinogens for a nested case-control study of lung cancer mortality among European asphalt workers. Company questionnaires and structured questionnaires used in interviews and industry-specific job-exposure matrices (JEMs) were elaborated and applied. Three sources of information were eventually used for exposure assessment and assignment: (i) data obtained in cohort phase, (ii) data from living subjects, next-of-kin, and fellow-workers questionnaires, and (iii) JEMs for bitumen exposure by inhalation and via skin and co-exposures to known or suspected lung carcinogens within and outside cohort companies. Inhalation and dermal exposure estimates for bitumen were adjusted for time trends, time spent in a job, and other determinants of exposure (e.g. oil gravel paving). Clothing patterns, personal protective devices, and personal hygiene were taken into consideration while estimating dermal exposure. Occupational exposures could be assessed for 433 cases and 1253 controls for relevant time periods. Only 43% of work histories were spent inside original asphalt and construction companies. A total of 95.8% of job periods in cohort companies could be coded at a more detailed level. Imputation of work time and 'hygienic behaviour' multipliers was needed for <10% of work history years. Overall, downward trends in exposure were present and differences existed between countries and companies. As expected, correlations were strongest (r > 0.7) among bitumen-related agents, while correlations between coal tar, bitumen-related agents, and established lung carcinogens were weaker (r < 0.4). A systematic and detailed approach was developed to estimate inhalation and dermal exposure for a nested case-control study among asphalt workers.

Navy Occupational Health Information Management System (NOHIMS). Environmental Exposure Module. Users’ Manual

DTIC Science & Technology

1987-01-16

menus , controls user and device access to the system, manages the security features associated with menus , devices, and users, provides...in the files, or the number of files in the system. 2-2 3.0 MODULE INPUT PROCESSES 3.1 Summary of Input Processes The EE module contains many menu ...Output Processes The EE module contains many menu options which enable the user to obtain needed information from the module. These options can be

Risk factors for tube exposure as a late complication of glaucoma drainage implant surgery.

PubMed

Chaku, Meenakshi; Netland, Peter A; Ishida, Kyoko; Rhee, Douglas J

2016-01-01

The purpose of this study was to evaluate the risk factors for tube exposure after glaucoma drainage implant surgery. This was a retrospective case-controlled observational study of 64 eyes from 64 patients. Thirty-two eyes of 32 patients with tube erosion requiring surgical revision were compared with 32 matched control eyes of 32 patients. Univariate and multivariate risk factor analyses were performed. Mean age was significantly younger in the tube exposure group compared with the control group (48.2±28.1 years versus 67.3±18.0 years, respectively; P=0.003). The proportion of diabetic patients (12.5%) in the tube exposure group was significantly less (P=0.041) compared with the control group (37.5%). Comparisons of the type and position of the drainage implant were not significantly different between the two groups. The average time to tube exposure was 17.2±18.0 months after implantation of the drainage device. In both univariate and multivariate analyses, younger age (P=0.005 and P=0.027) and inflammation prior to tube exposure (P≤0.001 and P=0.004) were significant risk factors. Diabetes was a significant risk factor only in the univariate analysis (P=0.027). Younger age and inflammation were significant risk factors for tube exposure after drainage implant surgery.

Reduction in radiation exposure to nursing personnel with the use of remote afterloading brachytherapy devices

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

Grigsby, P.W.; Perez, C.A.; Eichling, J.

The radiation exposure to nursing personnel from patients with brachytherapy implants on a large brachytherapy service were reviewed. Exposure to nurses, as determined by TLD monitors, indicates a 7-fold reduction in exposure after the implementation of the use of remote afterloading devices. Quarterly TLD monitor data for six quarters prior to the use of remote afterloading devices demonstrate an average projected annual dose equivalent to the nurses of 152 and 154 mrem (1.5 mSv). After the implementation of the remote afterloading devices, the quarterly TLD monitor data indicate an average dose equivalent per nurse of 23 and 19 mrem (0.2more » mSv). This is an 87% reduction in exposure to nurses with the use of these devices (p less than 0.01).« less

Automatic alternative phase-shift mask CAD layout tool for gate shrinkage of embedded DRAM in logic below 0.18 μm

NASA Astrophysics Data System (ADS)

Ohnuma, Hidetoshi; Kawahira, Hiroichi

1998-09-01

An automatic alternative phase shift mask (PSM) pattern layout tool has been newly developed. This tool is dedicated for embedded DRAM in logic device to shrink gate line width with improving line width controllability in lithography process with a design rule below 0.18 micrometers by the KrF excimer laser exposure. The tool can crete Levenson type PSM used being coupled with a binary mask adopting a double exposure method for positive photo resist. By using graphs, this tool automatically creates alternative PSM patterns. Moreover, it does not give any phase conflicts. By adopting it to actual embedded DRAM in logic cells, we have provided 0.16 micrometers gate resist patterns at both random logic and DRAM areas. The patterns were fabricated using two masks with the double exposure method. Gate line width has been well controlled under a practical exposure-focus window.

Excess of Radiation Burden for Young Testicular Cancer Patients using Automatic Exposure Control and Contrast Agent on Whole-body Computed Tomography Imaging.

PubMed

Niiniviita, Hannele; Kulmala, Jarmo; Pölönen, Tuukka; Määttänen, Heli; Järvinen, Hannu; Salminen, Eeva

2017-06-01

The aim of the study was to assess patient dose from whole-body computed tomography (CT) in association with patient size, automatic exposure control (AEC) and intravenous (IV) contrast agent. Sixty-five testicular cancer patients (mean age 28 years) underwent altogether 279 whole-body CT scans from April 2000 to April 2011. The mean number of repeated examinations was 4.3. The GE LightSpeed 16 equipped with AEC and the Siemens Plus 4 CT scanners were used for imaging. Whole-body scans were performed with (216) and without (63) IV contrast. The ImPACT software was used to determine the effective and organ doses. Patient doses were independent (p < 0.41) of patient size when the Plus 4 device (mean 7.4 mSv, SD 1.7 mSv) was used, but with the LightSpeed 16 AEC device, the dose (mean 14 mSv, SD 4.6 mSv) increased significantly (p < 0.001) with waist cirfumference. Imaging with the IV contrast agent caused significantly higher (13% Plus 4, 35% LightSpeed 16) exposure than non-contrast imaging (p < 0.001). Great caution on the use of IV contrast agent and careful set-up of the AEC modulation parameters is recommended to avoid excessive radiation exposure on the whole-body CT imaging of young patients.

Repeated or long-duration TASER electronic control device exposures: acidemia and lack of respiration.

PubMed

Jauchem, James R

2010-03-01

Conducted energy weapons (CEWs), such as TASER devices, may be applied to subjects in repeated or long-duration modes. Such applications may result in more potentially harmful effects (as reflected in blood factor changes) than shorter exposures. In this review, results from a number of studies of repeated and long-duration CEW exposures in an animal model are examined. Additionally, a few limited investigations of shorter CEW applications to human subjects are considered. Specifically, in anesthetized swine, increased blood acidity (acidemia) and lack of effective respiration were found to be common during or immediately after CEW exposure. The acidemia could have been due to both metabolic and respiratory acidosis. A relatively rapid recovery toward baseline pH levels occurred. The lack of effective respiration has not been verified in experiments of CEW applications to human subjects; however, in some incidents of human deaths after CEW exposures subjects have been reported to stop breathing immediately after the exposure. It is not known if all human subjects exposed to CEW applications in the field (often "on drugs" or "in excited delirium") would be able to maintain adequate breathing. Since a limited number of short CEW applications would be less likely to cause adverse effects, however, CEWs can still be a valuable tool for law enforcement activities.

40 CFR 171.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... to control the rate of dispersal, and droplet or particle size of a pesticide dispersed by the... pesticide which permits its use with other chemicals without undesirable results being caused by the... devices that shield against unintended exposure to pesticides. (22) The term regulated pest means a...

40 CFR 171.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... to control the rate of dispersal, and droplet or particle size of a pesticide dispersed by the... pesticide which permits its use with other chemicals without undesirable results being caused by the... devices that shield against unintended exposure to pesticides. (22) The term regulated pest means a...

40 CFR 171.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... to control the rate of dispersal, and droplet or particle size of a pesticide dispersed by the... pesticide which permits its use with other chemicals without undesirable results being caused by the... devices that shield against unintended exposure to pesticides. (22) The term regulated pest means a...

The Impact of the Newer Television Technologies on Television Satisfaction.

ERIC Educational Resources Information Center

Perse, Elizabeth M.; Ferguson, Douglas A.

1993-01-01

Finds that use of new television technologies (cable television, videocassette recorders, and remote control devices) had an impact on receiving, pass-the-time, and companionship gratifications from television viewing. Shows that instrumental viewing motives, television exposure, and receiving informational gratifications from television viewing…

Extremely low frequency (ELF) stray magnetic fields of laboratory equipment: a possible co-exposure conducting experiments on cell cultures.

PubMed

Gresits, Iván; Necz, Péter Pál; Jánossy, Gábor; Thuróczy, György

2015-09-01

Measurements of extremely low frequency (ELF) magnetic fields were conducted in the environment of commercial laboratory equipment in order to evaluate the possible co-exposure during the experimental processes on cell cultures. Three types of device were evaluated: a cell culture CO2 incubator, a thermostatic water bath and a laboratory shaker table. These devices usually have electric motors, heating wires and electronic control systems, therefore may expose the cell cultures to undesirable ELF stray magnetic fields. Spatial distributions of magnetic field time domain signal waveform and frequency spectral analysis (FFT) were processed. Long- and short-term variation of stray magnetic field was also evaluated under normal use of investigated laboratory devices. The results show that the equipment under test may add a considerable ELF magnetic field to the ambient environmental magnetic field or to the intentional exposure to ELF, RF or other physical/chemical agents. The maximum stray magnetic fields were higher than 3 µT, 20 µT and 75 µT in the CO2 incubator, in water bath and on the laboratory shaker table, respectively, with high variation of spatial distribution and time domain. Our investigation emphasizes possible confounding factors conducting cell culture studies related to low-level ELF-EMF exposure due to the existing stray magnetic fields in the ambient environment of laboratory equipment.

Radiology Technician (AFSC 90370).

ERIC Educational Resources Information Center

Sobczak, James

This five-volume student text is designed for use by Air Force personnel enrolled in a self-study extension course for radiology technicians. Covered in the individual volumes are radiographic fundamentals (x-ray production; primary beams; exposure devices; film, film holders, and darkrooms; control of film quality; and environmental safety);…

Computer-automated silica aerosol generator and animal inhalation exposure system

PubMed Central

McKinney, Walter; Chen, Bean; Schwegler-Berry, Diane; Frazer, Dave G.

2015-01-01

Inhalation exposure systems are necessary tools for determining the dose response relationship of inhaled toxicants under a variety of exposure conditions. The objective of this study was to develop an automated computer controlled system to expose small laboratory animals to precise concentrations of uniformly dispersed airborne silica particles. An acoustical aerosol generator was developed which was capable of re-suspending particles from bulk powder. The aerosolized silica output from the generator was introduced into the throat of a venturi tube. The turbulent high-velocity air stream within the venturi tube increased the dispersion of the re-suspended powder. That aerosol was then used to expose small laboratory animals to constant aerosol concentrations, up to 20mg/m3, for durations lasting up to 8h. Particle distribution and morphology of the silica aerosol delivered to the exposure chamber were characterized to verify that a fully dispersed and respirable aerosol was being produced. The inhalation exposure system utilized a combination of airflow controllers, particle monitors, data acquisition devices and custom software with automatic feedback control to achieve constant and repeatable exposure environments. The automatic control algorithm was capable of maintaining median aerosol concentrations to within ±0.2 mg/m3 of a user selected target concentration during exposures lasting from 2 to 8 h. The system was able to reach 95% of the desired target value in <10min during the beginning phase of an exposure. This exposure system provided a highly automated tool for conducting inhalation toxicology studies involving silica particles. PMID:23796015

Improving overlay control through proper use of multilevel query APC

NASA Astrophysics Data System (ADS)

Conway, Timothy H.; Carlson, Alan; Crow, David A.

2003-06-01

Many state-of-the-art fabs are operating with increasingly diversified product mixes. For example, at Cypress Semiconductor, it is not unusual to be concurrently running multiple technologies and many devices within each technology. This diverse product mix significantly increases the difficulty of manually controlling overlay process corrections. As a result, automated run-to-run feedforward-feedback control has become a necessary and vital component of manufacturing. However, traditional run-to-run controllers rely on highly correlated historical events to forecast process corrections. For example, the historical process events typically are constrained to match the current event for exposure tool, device, process level and reticle ID. This narrowly defined process stream can result in insufficient data when applied to lowvolume or new-release devices. The run-to-run controller implemented at Cypress utilizes a multi-level query (Level-N) correlation algorithm, where each subsequent level widens the search criteria for available historical data. The paper discusses how best to widen the search criteria and how to determine and apply a known bias to account for tool-to-tool and device-to-device differences. Specific applications include offloading lots from one tool to another when the first tool is down for preventive maintenance, utilizing related devices to determine a default feedback vector for new-release devices, and applying bias values to account for known reticle-to-reticle differences. In this study, we will show how historical data can be leveraged from related devices or tools to overcome the limitations of narrow process streams. In particular, this paper discusses how effectively handling narrow process streams allows Cypress to offload lots from a baseline tool to an alternate tool.

The associations of mobile touch screen device use with musculoskeletal symptoms and exposures: A systematic review

PubMed Central

Toh, Siao Hui; Coenen, Pieter; Howie, Erin K.

2017-01-01

Background The use of mobile touch screen devices (MTSDs) has increased rapidly over the last decade, and there are concerns that their use may have negative musculoskeletal consequences; yet evidence on the association of MTSD use with musculoskeletal symptoms and exposures is currently dispersed. The aim of this study was to systematically review available literature on musculoskeletal symptoms and exposures associated with MTSD use. The synthesised information may facilitate wise use of MTSDs and may identify areas in need of further research. Methods EMBASE, Medline, Scopus, PsycINFO and Proquest electronic databases were searched for articles published up to June 2016, using keywords describing MTSD, musculoskeletal symptoms (e.g. pain, discomfort) and musculoskeletal exposures (e.g. posture, muscle activity). Two reviewers independently screened the articles, extracted relevant data and assessed methodological quality of included studies. Due to heterogeneity in the studies, a meta-analysis was not possible and a structured narrative synthesis of the findings was undertaken. Results A total of 9,908 articles were screened for eligibility with 45 articles finally included for review. Included articles were of cross-sectional, case-control or experimental laboratory study designs. No longitudinal studies were identified. Findings were presented and discussed in terms of the amount, features, tasks and positions of MTSD use and its association with musculoskeletal symptoms and musculoskeletal exposures. Conclusions There is limited evidence that MTSD use, and various aspects of its use (i.e. amount of usage, features, tasks and positions) are associated with musculoskeletal symptoms and exposures. This is due to mainly low quality experimental and case-control laboratory studies, with few cross-sectional and no longitudinal studies. Further research is warranted in order to develop guidelines for wise use of MTSDs. PMID:28787453

Assessment of arsenic exposures and controls in gallium arsenide production.

PubMed

Sheehy, J W; Jones, J H

1993-02-01

The electronics industry is expanding the use of gallium arsenide in the production of optoelectronic devices and integrated circuits. Workers in the electronics industry using gallium arsenide are exposed to hazardous substances such as arsenic, arsine, and various acids. Arsenic requires stringent controls to minimize exposures (the current OSHA PEL for arsenic is 10 micrograms/m3 and the NIOSH REL is 2 micrograms/m3 ceiling). Inorganic arsenic is strongly implicated in respiratory tract and skin cancer. For these reasons, NIOSH researchers conducted a study of control systems for facilities using gallium arsenide. Seven walk-through surveys were performed to identify locations for detailed study which appeared to have effective controls; three facilities were chosen for in-depth evaluation. The controls were evaluated by industrial hygiene sampling. Including personal breathing zone and area air sampling for arsenic and arsine; wipe samples for arsenic also were collected. Work practices and the use of personal protective equipment were documented. This paper reports on the controls and the arsenic exposure results from the evaluation of the following gallium arsenide processes: Liquid Encapsulated Czochralski (LEC) and Horizontal Bridgeman (HB) crystal growing, LEC cleaning operations, ingot grinding/wafer sawing, and epitaxy. Results at one plant showed that in all processes except epitaxy, average arsenic exposures were at or above the OSHA action level of 5 micrograms/m3. While cleaning the LEC crystal pullers, the average potential arsenic exposure of the cleaning operators was 100 times the OSHA PEL. At the other two plants, personal exposures for arsenic were well controlled in LEC, LEC cleaning, grinding/sawing, and epitaxy operations.

An experimental model to measure the ability of headphones with active noise control to reduce patient's exposure to noise in an intensive care unit.

PubMed

Gallacher, Stuart; Enki, Doyo; Stevens, Sian; Bennett, Mark J

2017-10-17

Defining the association between excessive noise in intensive care units, sleep disturbance and morbidity, including delirium, is confounded by the difficulty of implementing successful strategies to reduce patient's exposure to noise. Active noise control devices may prove to be useful adjuncts but there is currently little to quantify their ability to reduce noise in this complex environment. Sound meters were embedded in the auditory meatus of three polystyrene model heads with no headphones (control), with headphones alone and with headphones using active noise control and placed in patient bays in a cardiac ICU. Ten days of recording sound levels at a frequency of 1 Hz were performed, and the noise levels in each group were compared using repeated measures MANOVA and subsequent pairwise testing. Multivariate testing demonstrated that there is a significant difference in the mean noise exposure levels between the three groups (p < 0.001). Subsequent pairwise testing between the three groups shows that the reduction in noise is greatest with headphones and active noise control. The mean reduction in noise exposure between the control and this group over 24 h is 6.8 (0.66) dB. The use of active noise control was also associated with a reduction in the exposure to high-intensity sound events over the course of the day. The use of active noise cancellation, as delivered by noise-cancelling headphones, is associated with a significant reduction in noise exposure in our model of noise exposure in a cardiac ICU. This is the first study to look at the potential effectiveness of active noise control in adult patients in an intensive care environment and shows that active noise control is a candidate technology to reduce noise exposure levels the patients experience during stays on intensive care.

Ultrasound: biological effects and industrial hygiene concerns.

PubMed

Wiernicki, C; Karoly, W J

1985-09-01

Due to the increased use of high intensity ultrasonic devices, there is now a greater risk of worker exposure to ultrasonic radiation than there was in the past. Exposure to high power ultrasound may produce adverse biological effects. High power ultrasound, characterized by high intensity outputs at frequencies of 20-100 kHz, has a wide range of applications throughout industry. Future applications may involve equipment with higher energy outputs. Contact ultrasound, i.e., no airspace between the energy source and the biological tissue, is significantly more hazardous than exposure to airborne ultrasound because air transmits less than one percent of the energy. This paper discusses biological effects associated with overexposure to ultrasound, exposure standards proposed for airborne and contact ultrasound, industrial hygiene controls that can be employed to minimize exposure, and the instrumentation that is required for evaluating exposures.

Line-edge quality optimization of electron beam resist for high-throughput character projection exposure utilizing atomic force microscope analysis

NASA Astrophysics Data System (ADS)

Ikeno, Rimon; Mita, Yoshio; Asada, Kunihiro

2017-04-01

High-throughput electron-beam lithography (EBL) by character projection (CP) and variable-shaped beam (VSB) methods is a promising technique for low-to-medium volume device fabrication with regularly arranged layouts, such as standard-cell logics and memory arrays. However, non-VLSI applications like MEMS and MOEMS may not fully utilize the benefits of CP method due to their wide variety of layout figures including curved and oblique edges. In addition, the stepwise shapes that appear on such irregular edges by VSB exposure often result in intolerable edge roughness, which may degrade performances of the fabricated devices. In our former study, we proposed a general EBL methodology for such applications utilizing a combination of CP and VSB methods, and demonstrated its capabilities in electron beam (EB) shot reduction and edge-quality improvement by using a leading-edge EB exposure tool, ADVANTEST F7000S-VD02, and high-resolution Hydrogen Silsesquioxane resist. Both scanning electron microscope and atomic force microscope observations were used to analyze quality of the resist edge profiles to determine the influence of the control parameters used in the exposure-data preparation process. In this study, we carried out detailed analysis of the captured edge profiles utilizing Fourier analysis, and successfully distinguish the systematic undulation by the exposed CP character profiles from random roughness components. Such capability of precise edge-roughness analysis is useful to our EBL methodology to maintain both the line-edge quality and the exposure throughput by optimizing the control parameters in the layout data conversion.

Exposed Subcutaneous Implantable Devices: An Operative Protocol for Management and Salvage

PubMed Central

D’Arpa, Salvatore; Cordova, Adriana; Moschella, Francesco

2015-01-01

Background: Implantable venous and electrical devices are prone to exposure and infection. Indications for management are controversial, but—especially if infected—exposed devices are often removed and an additional operation is needed to replace the device, causing a delay in chemotherapy and prolonging healing time. We present our protocol for device salvage, on which limited literature is available. Methods: Between 2007 and 2013, 17 patients were treated (12 venous access ports, 3 cardiac pacemakers, and 2 subcutaneous neural stimulators). Most patients were operated within 7 days from exposure. All patients received only a single perioperative dose of prophylactic antibiotic. In cases of gross infection (n = 1), the device was immediately replaced. In the absence of clinical signs of infection: Complete capsulectomy and aggressive cleaning with an n-acetylcysteine solution and saline solution. Primary exposure of venous ports with sufficient skin coverage (n = 10): the device was covered with local skin flaps. Recurrent cases, cases with insufficient skin coverage or big devices (n = 7): the device was moved to a subpectoral pocket. Mean follow-up was 19 months. Results: Sixteen devices were saved. Only one grossly infected pacemaker was removed and replaced immediately. Only in 1 case, exposure of a venous port recurred after 18 months and was successfully moved to a subpectoral pocket. Chemotherapy was always restarted as scheduled and electrical devices remained functional. Conclusions: This protocol allows—with a straightforward operation and simple measures—to save exposed devices even several days after exposure. Submuscular placement or immediate replacement is indicated only in selected cases. PMID:26034650

TOLERANCE AND SENSITIZATION TO WEEKLY NICOTINE EXPOSURES ON THE MOTOR ACTIVITY OF RATS.

EPA Science Inventory

Motor activity was examined in adult female Long-Evans rats in a photocell device during daily (M-F) 30-min sessions. Following adaptation to the testing routine the rats were divided into six groups of eight that were designated to receive either nothing (non-injected control),...

Noble metals: a toxicological appraisal of potential new environmental contaminants.

PubMed Central

Brubaker, P E; Moran, J P; Bridbord, K; Hueter, F G

1975-01-01

The public health benefits expected by reducing known hazardous emissions from mobile sources should not be compromised by increasing levels of other potentially hazardous unregulated emissions. Catalytic converters are going to be used to meet the statutory requirements on carbon monoxide and hydrocarbon emissions from light duty motor vehicles. Platinum and palladium metals are the catalytic materials to be used in these emission control devices. Preliminary experimental evidence and analysis of the impact of these control devices on the future use and demand for platinum indicates that this metal may appear at detectable levels in the environment by the end of this decade. At the present time, platinum and palladium are not present in the public environment and represent potentially new environmental contaminants as a consequence of use of this new abatement control technology. There is relatively little information available to adequately assess the potential health hazards that may be associated with exposure to these metals and their compounds. Analysis of the environmental problems and concerns associated with possible new environmental contaminants are discussed. Limited estimates are made on community exposure by use of a meteorological dispersion model. Biodegradation potential and attention is also given to the limited toxicological information available. PMID:50939

Electromagnetic interference in cardiac rhythm management devices.

PubMed

Sweesy, Mark W; Holland, James L; Smith, Kerry W

2004-01-01

Clinicians caring for cardiac device patients with implanted pacemakers or cardioverter defibrillators (ICDs) are frequently asked questions by their patients concerning electromagnetic interference (EMI) sources and the devices. EMI may be radiated or conducted and may be present in many different forms including (but not limited to) radiofrequency waves, microwaves, ionizing radiation, acoustic radiation, static and pulsed magnetic fields, and electric currents. Manufacturers have done an exemplary job of interference protection with device features such as titanium casing, signal filtering, interference rejection circuits, feedthrough capacitors, noise reversion function, and programmable parameters. Nevertheless, EMI remains a real concern and a potential danger. Many factors influence EMI including those which the patient can regulate (eg, distance from and duration of exposure) and some the patient cannot control (eg, intensity of the EMI field, signal frequency). Potential device responses are many and range from simple temporary oversensing to permanent device damage Several of the more common EMI-generating devices and their likely effects on cardiac devices are considered in the medical, home, and daily living and work environments.

Design on the x-ray oral digital image display card

NASA Astrophysics Data System (ADS)

Wang, Liping; Gu, Guohua; Chen, Qian

2009-10-01

According to the main characteristics of X-ray imaging, the X-ray display card is successfully designed and debugged using the basic principle of correlated double sampling (CDS) and combined with embedded computer technology. CCD sensor drive circuit and the corresponding procedures have been designed. Filtering and sampling hold circuit have been designed. The data exchange with PC104 bus has been implemented. Using complex programmable logic device as a device to provide gating and timing logic, the functions which counting, reading CPU control instructions, corresponding exposure and controlling sample-and-hold have been completed. According to the image effect and noise analysis, the circuit components have been adjusted. And high-quality images have been obtained.

Imaging-based dust sensors: equipment and methods

NASA Astrophysics Data System (ADS)

Bonifazi, Giuseppe; Greco, Sonia

2004-05-01

Dust detection and control in real time, represent one of the most challenging problem in all those environments where fine and ultrafine airborne particulate solids products are present. The presence of such products can be linked to several factors, often directly related and influenced by the working-production actions performed. Independently from the causes generating dust, airborne contaminants are an occupational problem of increasing interest as they are related to a wide number of diseases. In particular, airborne dusts are well known to be associated with several classical occupational lung diseases, such as the pneumoconiosis, especially at high levels of exposure. Nowadays there is also an increasing interest in other dust related diseases, from the most serious as cancer and asthma, to those related with allergies or irritation and other illnesses, also occurring at lower levels of exposure. Among the different critical factors influencing health risk for airborne dust exposure, mainly four have to be considered, that is: i) nature of the dust resulting from working in terms of presence of specific poisoning material, i.e. free silica, and morphological and morphometrical attributes of particulates constituting airborne dust; ii) size of the particles, iii) duration of exposure time and, finally, iv) airborne dust concentration in the breathing zone where the worker performs his activity. A correct dust detection is not easy, especially if some of the previous mentioned factors, have to be detected and quantified in real time in order to define specific "on-line" control actions aimed to reduce the level of the exposure to dust of the workers, as for example: i) modification of aspirating devices operating condition, change of filtering cleaning sequence, etc. . The more severe are the environmental conditions, in terms of dust presence (in quantity and quality) more difficult is to utilize efficient sampling devices. Detection devices, in fact, tend to become "blind" to dust as dust presence increases, on the other hand severe dust production conditions is exactly the case where control strategies have to be applied to realize safer conditions for the workers. In this paper the possibility to utilize a new logic to perform an "on-line" airborne dust sampling and analysis utilizing imaging is described with particular reference to dusts flowing in a duct after the caption and before their abatement by classical mechanical filtering. The study was particularly addressed to define, design and implement a logic able to extract those parameters affecting airborne dust behavior with respect to its efficient abatement. All dust sampling was performed directly in an industrial plant where tests were carried out in a controlled environment.

Advanced plasma etch technologies for nanopatterning

NASA Astrophysics Data System (ADS)

Wise, Rich

2013-10-01

Advances in patterning techniques have enabled the extension of immersion lithography from 65/45 nm through 14/10 nm device technologies. A key to this increase in patterning capability has been innovation in the subsequent dry plasma etch processing steps. Multiple exposure techniques, such as litho-etch-litho-etch, sidewall image transfer, line/cut mask, and self-aligned structures, have been implemented to solution required device scaling. Advances in dry plasma etch process control across wafer uniformity and etch selectivity to both masking materials have enabled adoption of vertical devices and thin film scaling for increased device performance at a given pitch. Plasma etch processes, such as trilayer etches, aggressive critical dimension shrink techniques, and the extension of resist trim processes, have increased the attainable device dimensions at a given imaging capability. Precise control of the plasma etch parameters affecting across-design variation, defectivity, profile stability within wafer, within lot, and across tools has been successfully implemented to provide manufacturable patterning technology solutions. IBM has addressed these patterning challenges through an integrated total patterning solutions team to provide seamless and synergistic patterning processes to device and integration internal customers. We will discuss these challenges and the innovative plasma etch solutions pioneered by IBM and our alliance partners.

Advanced plasma etch technologies for nanopatterning

NASA Astrophysics Data System (ADS)

Wise, Rich

2012-03-01

Advances in patterning techniques have enabled the extension of immersion lithography from 65/45nm through 14/10nm device technologies. A key to this increase in patterning capability has been innovation in the subsequent dry plasma etch processing steps. Multiple exposure techniques such as litho-etch-litho-etch, sidewall image transfer, line/cut mask and self-aligned structures have been implemented to solution required device scaling. Advances in dry plasma etch process control, across wafer uniformity and etch selectivity to both masking materials and have enabled adoption of vertical devices and thin film scaling for increased device performance at a given pitch. Plasma etch processes such as trilayer etches, aggressive CD shrink techniques, and the extension of resist trim processes have increased the attainable device dimensions at a given imaging capability. Precise control of the plasma etch parameters affecting across design variation, defectivity, profile stability within wafer, within lot, and across tools have been successfully implemented to provide manufacturable patterning technology solutions. IBM has addressed these patterning challenges through an integrated Total Patterning Solutions team to provide seamless and synergistic patterning processes to device and integration internal customers. This paper will discuss these challenges and the innovative plasma etch solutions pioneered by IBM and our alliance partners.

Mice and the A-Bomb: Irradiation Systems for Realistic Exposure Scenarios.

PubMed

Garty, Guy; Xu, Yanping; Elliston, Carl; Marino, Stephen A; Randers-Pehrson, Gerhard; Brenner, David J

2017-04-01

Validation of biodosimetry assays is normally performed with acute exposures to uniform external photon fields. Realistically, exposure to a radiological dispersal device or reactor leak will include exposure to low dose rates and likely exposure to ingested radionuclides. An improvised nuclear device will likely include a significant neutron component in addition to a mixture of high- and low-dose-rate photons and ingested radionuclides. We present here several novel irradiation systems developed at the Center for High Throughput Minimally Invasive Radiation Biodosimetry to provide more realistic exposures for testing of novel biodosimetric assays. These irradiators provide a wide range of dose rates (from Gy/s to Gy/week) as well as mixed neutron/photon fields mimicking an improvised nuclear device.

Mice and the A-Bomb: Irradiation Systems for Realistic Exposure Scenarios

PubMed Central

Garty, Guy; Xu, Yanping; Elliston, Carl; Marino, Stephen A.; Randers-Pehrson, Gerhard; Brenner, David J.

2017-01-01

Validation of biodosimetry assays is normally performed with acute exposures to uniform external photon fields. Realistically, exposure to a radiological dispersal device or reactor leak will include exposure to low dose rates and likely exposure to ingested radionuclides. An improvised nuclear device will likely include a significant neutron component in addition to a mixture of high- and low-dose-rate photons and ingested radionuclides. We present here several novel irradiation systems developed at the Center for High Throughput Minimally Invasive Radiation Biodosimetry to provide more realistic exposures for testing of novel biodosimetric assays. These irradiators provide a wide range of dose rates (from Gy/s to Gy/week) as well as mixed neutron/photon fields mimicking an improvised nuclear device. PMID:28211757

The infant incubator in the neonatal intensive care unit: unresolved issues and future developments.

PubMed

Antonucci, Roberto; Porcella, Annalisa; Fanos, Vassilios

2009-01-01

Since the 19th century, devices termed incubators were developed to maintain thermal stability in low birth weight (LBW) and sick newborns, thus improving their chances of survival. Remarkable progress has been made in the production of infant incubators, which are currently highly technological devices. However, they still need to be improved in many aspects. Regarding the temperature and humidity control, future incubators should minimize heat loss from the neonate and eddies around him/her. An unresolved issue is exposure to high noise levels in the Neonatal Intensive Care Unit (NICU). Strategies aimed at modifying the behavior of NICU personnel, along with structural improvements in incubator design, are required to reduce noise exposure. Light environment should be taken into consideration in designing new models of incubators. In fact, ambient NICU illumination may cause visual pathway sequelae or possibly retinopathy of prematurity (ROP), while premature exposure to continuous lighting may adversely affect the rest-activity patterns of the newborn. Accordingly, both the use of incubator covers and circadian lighting in the NICU might attenuate these effects. The impact of electromagnetic fields (EMFs) on infant health is still unclear. However, future incubators should be designed to minimize the EMF exposure of the newborn.

[Virtual reality therapy in anxiety disorders].

PubMed

Mitrousia, V; Giotakos, O

2016-01-01

During the last decade a number of studies have been conducted in order to examine if virtual reality exposure therapy can be an alternative form of therapy for the treatment of mental disorders and particularly for the treatment of anxiety disorders. Imaginal exposure therapy, which is one of the components of Cognitive Behavioral Therapy, cannot be easily applied to all patients and in cases like those virtual reality can be used as an alternative or a supportive psychotherapeutic technique. Most studies using virtual reality have focused on anxiety disorders, mainly in specific phobias, but some extend to other disorders such as eating disorders, drug dependence, pain control and palliative care and rehabilitation. Main characteristics of virtual reality therapy are: "interaction", "immersion", and "presence". High levels of "immersion" and "presence" are associated with increased response to exposure therapy in virtual environments, as well as better therapeutic outcomes and sustained therapeutic gains. Typical devices that are used in order patient's immersion to be achieved are the Head-Mounted Displays (HMD), which are only for individual use, and the computer automatic virtual environment (CAVE), which is a multiuser. Virtual reality therapy's disadvantages lie in the difficulties that arise due to the demanded specialized technology skills, devices' cost and side effects. Therapists' training is necessary in order for them to be able to manipulate the software and the hardware and to adjust it to each case's needs. Devices' cost is high but as technology continuously improves it constantly decreases. Immersion during virtual reality therapy can induce mild and temporary side effects such as nausea, dizziness or headache. Until today, however, experience shows that virtual reality offers several advantages. Patient's avoidance to be exposed in phobic stimuli is reduced via the use of virtual reality since the patient is exposed to them as many times as he wishes and under the supervision of the therapist. The technique takes place in the therapist's office which ensures confidentiality and privacy. The therapist is able to control unpredicted events that can occur during patient's exposure in real environments. Mainly the therapist can control the intensity of exposure and adapt it to the patient's needs. Virtual reality can be proven particularly useful in some specific psychological states. For instance, patients with post-traumatic stress disorder (PTSD) who prone to avoid the reminders of the traumatic events. Exposure in virtual reality can solve this problem providing to the patient a large number of stimuli that activate the senses causing the necessary physiological and psychological anxiety reactions, regardless of his willingness or ability to recall in his imagination the traumatic event.

Photographic Equipment Test System (PETS)

NASA Technical Reports Server (NTRS)

1975-01-01

The Photographic Equipment Test System is presented. The device is a mobile optical system designed for evaluating performance of various sensors in a laboratory, in a vacuum chamber or on a flight line. The carriage is designed to allow elevation as well as azimuth control of the direction of the light from the collimator. The pneumatic tires provide an effective vibration isolation system. A target/illumination system is mounted on a motor driven linear slide, and focusing and exposure control can be operated remotely from the small electronics control console.

Exposure of healthy subjects with emissions from a gas metal arc welding process: part 1--exposure technique and external exposure.

PubMed

Brand, P; Havlicek, P; Steiners, M; Holzinger, K; Reisgen, U; Kraus, T; Gube, M

2013-01-01

Studies concerning welding fume-related adverse health effects in welders are hampered by the heterogeneity of workplace situations, resulting in complex and non-standardized exposure conditions. In order to carry out welding fume exposure studies under controlled and standardized conditions, the Aachen Workplace Simulation Laboratory was developed. This laboratory consists of an emission room, in which welding fume is produced, and an exposure room in which human subjects are exposed to these fumes. Both rooms are connected by a ventilation system which allows the welding fume concentration to be regulated. Particle mass concentration was measured with a TEOM microbalance and the particle number-size distribution using a Grimm SMPS device. In a study, which is the subject of this paper, it has been shown that welding fume concentration can easily be regulated between 1 and about 3 mg m(-3). The chosen concentration can be kept constant for more than 8 h. However, transport of the particles from the emission room into the exposure room leads to a change in particle size distribution, which is probably due to coagulation of the fraction of smallest particles. The Aachen Workplace Simulation Laboratory is suitable for controlled exposure studies with human subjects.

Common sole larvae survive high levels of pile-driving sound in controlled exposure experiments.

PubMed

Bolle, Loes J; de Jong, Christ A F; Bierman, Stijn M; van Beek, Pieter J G; van Keeken, Olvin A; Wessels, Peter W; van Damme, Cindy J G; Winter, Hendrik V; de Haan, Dick; Dekeling, René P A

2012-01-01

In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at which (sub-)lethal effects occur is limited for juvenile and adult fish, and virtually non-existent for fish eggs and larvae. A device was developed in which fish larvae can be exposed to underwater sound. It consists of a rigid-walled cylindrical chamber driven by an electro-dynamical sound projector. Samples of up to 100 larvae can be exposed simultaneously to a homogeneously distributed sound pressure and particle velocity field. Recorded pile-driving sounds could be reproduced accurately in the frequency range between 50 and 1000 Hz, at zero to peak pressure levels up to 210 dB re 1µPa(2) (zero to peak pressures up to 32 kPa) and single pulse sound exposure levels up to 186 dB re 1µPa(2)s. The device was used to examine lethal effects of sound exposure in common sole (Solea solea) larvae. Different developmental stages were exposed to various levels and durations of pile-driving sound. The highest cumulative sound exposure level applied was 206 dB re 1µPa(2)s, which corresponds to 100 strikes at a distance of 100 m from a typical North Sea pile-driving site. The results showed no statistically significant differences in mortality between exposure and control groups at sound exposure levels which were well above the US interim criteria for non-auditory tissue damage in fish. Although our findings cannot be extrapolated to fish larvae in general, as interspecific differences in vulnerability to sound exposure may occur, they do indicate that previous assumptions and criteria may need to be revised.

Common Sole Larvae Survive High Levels of Pile-Driving Sound in Controlled Exposure Experiments

PubMed Central

Bolle, Loes J.; de Jong, Christ A. F.; Bierman, Stijn M.; van Beek, Pieter J. G.; van Keeken, Olvin A.; Wessels, Peter W.; van Damme, Cindy J. G.; Winter, Hendrik V.; de Haan, Dick; Dekeling, René P. A.

2012-01-01

In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at which (sub-)lethal effects occur is limited for juvenile and adult fish, and virtually non-existent for fish eggs and larvae. A device was developed in which fish larvae can be exposed to underwater sound. It consists of a rigid-walled cylindrical chamber driven by an electro-dynamical sound projector. Samples of up to 100 larvae can be exposed simultaneously to a homogeneously distributed sound pressure and particle velocity field. Recorded pile-driving sounds could be reproduced accurately in the frequency range between 50 and 1000 Hz, at zero to peak pressure levels up to 210 dB re 1µPa2 (zero to peak pressures up to 32 kPa) and single pulse sound exposure levels up to 186 dB re 1µPa2s. The device was used to examine lethal effects of sound exposure in common sole (Solea solea) larvae. Different developmental stages were exposed to various levels and durations of pile-driving sound. The highest cumulative sound exposure level applied was 206 dB re 1µPa2s, which corresponds to 100 strikes at a distance of 100 m from a typical North Sea pile-driving site. The results showed no statistically significant differences in mortality between exposure and control groups at sound exposure levels which were well above the US interim criteria for non-auditory tissue damage in fish. Although our findings cannot be extrapolated to fish larvae in general, as interspecific differences in vulnerability to sound exposure may occur, they do indicate that previous assumptions and criteria may need to be revised. PMID:22431996

Effectiveness of a Closed-System Transfer Device in Reducing Surface Contamination in a New Antineoplastic Drug-Compounding Unit: A Prospective, Controlled, Parallel Study

PubMed Central

Pinturaud, Marine; Soichot, Marion; Richeval, Camille; Humbert, Luc; Lebecque, Michèle; Sidikou, Ousseini; Barthelemy, Christine; Bonnabry, Pascal; Allorge, Delphine; Décaudin, Bertrand; Odou, Pascal

2016-01-01

Background The objective of this randomized, prospective and controlled study was to investigate the ability of a closed-system transfer device (CSTD; BD-Phaseal) to reduce the occupational exposure of two isolators to 10 cytotoxic drugs and compare to standard compounding devices. Methods and Findings The 6-month study started with the opening of a new compounding unit. Two isolators were set up with 2 workstations each, one to compound with standard devices (needles and spikes) and the other using the Phaseal system. Drugs were alternatively compounded in each isolator. Sampling involved wiping three surfaces (gloves, window, worktop), before and after a cleaning process. Exposure to ten antineoplastic drugs (cyclophosphamide, ifosfamide, dacarbazine, 5-FU, methotrexate, gemcitabine, cytarabine, irinotecan, doxorubicine and ganciclovir) was assessed on wipes by LC-MS/MS analysis. Contamination rates were compared using a Chi2 test and drug amounts by a Mann-Whitney test. Significance was defined for p<0.05. Overall contamination was lower in the “Phaseal” isolator than in the “Standard” isolator (12.24% vs. 26.39%; p < 0.0001) although it differed according to drug. Indeed, the contamination rates of gemcitabine were 49.3 and 43.4% (NS) for the Standard and Phaseal isolators, respectively, whereas for ganciclovir, they were 54.2 and 2.8% (p<0.0001). Gemcitabine amounts were 220.6 and 283.6 ng for the Standard and Phaseal isolators (NS), and ganciclovir amounts were 179.9 and 2.4 ng (p<0.0001). Conclusion This study confirms that using a CSTD may significantly decrease the chemical contamination of barrier isolators compared to standard devices for some drugs, although it does not eliminate contamination totally. PMID:27391697

29 CFR 1910.1044 - 1,2-dibromo-3-chloropropane.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., transportation, distribution or sale of DBCP in intact containers sealed in such a manner as to prevent exposure... containers, or failure of control equipment which may, or does, result in an unexpected release of DBCP. OSHA... devices and work clothing shall be placed and stored in closed containers which prevent dispersion of the...

46 CFR 160.062-4 - Inspections and tests.

Code of Federal Regulations, 2013 CFR

2013-10-01

... required under § 160.062-3(b) while the device is submerged in water or in a water-filled pressure testing... manual control as a result of the low temperature exposure. (iii) Corrosion resisting test. After the completion of its temperature test, a hydraulic release sample shall be exposed to a 20 percent salt spray...

46 CFR 160.062-4 - Inspections and tests.

Code of Federal Regulations, 2014 CFR

2014-10-01

... required under § 160.062-3(b) while the device is submerged in water or in a water-filled pressure testing... manual control as a result of the low temperature exposure. (iii) Corrosion resisting test. After the completion of its temperature test, a hydraulic release sample shall be exposed to a 20 percent salt spray...

46 CFR 160.062-4 - Inspections and tests.

Code of Federal Regulations, 2012 CFR

2012-10-01

... required under § 160.062-3(b) while the device is submerged in water or in a water-filled pressure testing... manual control as a result of the low temperature exposure. (iii) Corrosion resisting test. After the completion of its temperature test, a hydraulic release sample shall be exposed to a 20 percent salt spray...

46 CFR 160.062-4 - Inspections and tests.

Code of Federal Regulations, 2011 CFR

2011-10-01

... required under § 160.062-3(b) while the device is submerged in water or in a water-filled pressure testing... manual control as a result of the low temperature exposure. (iii) Corrosion resisting test. After the completion of its temperature test, a hydraulic release sample shall be exposed to a 20 percent salt spray...

Risk management policies and practices regarding radio frequency electromagnetic fields: results from a WHO survey.

PubMed

Dhungel, Amit; Zmirou-Navier, Denis; van Deventer, Emilie

2015-04-01

This study aims to describe current risk management practices and policies across the world in relation to personal exposures from devices emitting radiofrequency fields, environmental exposures from fixed installations and exposures in the work environment. Data from 86 countries representing all WHO regions were collected through a survey. The majority of countries (76.8 %) had set exposure limits for mobile devices, almost all (90.7 %) had set public exposure limits for fixed installations and 76.5 % had specified exposure limits for personnel in occupational settings. A number of other policies had been implemented at the national level, ranging from information provisions on how to reduce personal exposures and restrictions of usage for certain populations, such as children or pregnant women to prevention of access around base stations. This study suggests that countries with higher mobile subscriptions tend to have set radiofrequency exposure limits for mobile devices and to have provisions on exposure measurements about fixed installations. © The Author 2014. Published by Oxford University Press.

Survival and behavioral effects of exposure to a hydrokinetic turbine on juvenile Atlantic salmon and adult American shad

USGS Publications Warehouse

Castro-Santos, Theodore R.; Haro, Alex

2015-01-01

This paper describes a series of experiments designed to measure the effect of exposure to a full-scale, vertical axis hydrokinetic turbine on downstream migrating juvenile Atlantic salmon (N=75) and upstream migrating adult American shad (N=208). Controlled studies were performed in a large-scale, open-channel flume, and all individuals approached the turbine under volitional control. No injuries were observed, and there was no measurable increase in mortality associated with turbine passage. Exposure to the turbine elicited behavioral responses from both species, however, with salmon passing primarily over the downrunning blades. Shad movement was impeded by the device, as indicated by fewer attempts of shorter duration and reduced distance of ascent up the flume. More work should be performed in both laboratory and field conditions to determine to what extent these effects are likely to influence free-swimming fish.

75 FR 8375 - Device Improvements to Reduce Unnecessary Radiation Exposure From Medical Imaging; Public Meeting...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-24

... radiologic technologists or technologists in other specialties as well as physicians in all medical...] Device Improvements to Reduce Unnecessary Radiation Exposure From Medical Imaging; Public Meeting... Improvements to Reduce Unnecessary Radiation Exposure From Medical Imaging.'' The purpose of this meeting is to...

Critical Evaluation of Air-Liquid Interface Exposure Devices for In Vitro Assessment of Atmospheric Pollutants

EPA Science Inventory

Exposure of cells to atmospheric pollutants at the air-liquid interface (ALI) is a more realistic approach than exposures of attached cells submerged in liquid medium. However, there is still limited understanding of the ideal ALI device design features that permit reproducible a...

Photodynamic Therapy: Occupational Hazards and Preventative Recommendations for Clinical Administration by Healthcare Providers

PubMed Central

Lacey, Steven E.; Vesper, Benjamin J.; Paradise, William A.; Radosevich, James A.; Colvard, Michael D.

2013-01-01

Abstract Objective: Photodynamic therapy (PDT) as a medical treatment for cancers is an increasing practice in clinical settings, as new photosensitizing chemicals and light source technologies are developed and applied. PDT involves dosing patients with photosensitizing drugs, and then exposing them to light using a directed energy device in order to manifest a therapeutic effect. Healthcare professionals providing PDT should be aware of potential occupational health and safety hazards posed by these treatment devices and photosensitizing agents administered to patients. Materials and methods: Here we outline and identify pertinent health and safety considerations to be taken by healthcare staff during PDT procedures. Results: Physical hazards (for example, non-ionizing radiation generated by the light-emitting device, with potential for skin and eye exposure) and chemical hazards (including the photosensitizing agents administered to patients that have the potential for exposure via skin, subcutaneous, ingestion, or inhalation routes) must be considered for safe use of PDT by the healthcare professional. Conclusions: Engineering, administrative, and personal protective equipment controls are recommendations for the safe use and handling of PDT agents and light-emitting technologies. PMID:23859750

Assessment of test method variables for in vitro skin irritation testing of medical device extracts.

PubMed

Olsen, Daniel S; Lee, Michelle; Turley, Audrey P

2018-08-01

Skin irritation is an important component of the biological safety evaluation of medical devices. This testing has typically been performed using in vivo models. However, in an effort to reduce the need for in vivo testing, alternative methods for assessing skin irritation potential in vitro have been developed using a Reconstructed Human Epidermis (RhE) model. During the development of the protocol for the round robin validation of in vitro irritation testing for medical device extracts, it became clear that there were three points in the procedure where different options may be validated within each laboratory for routine testing: sample exposure time (18 vs 24h), SDS positive control concentration, and cytokine (IL-1α) release testing. The goal of our study was to evaluate the effect of these variables. EpiDerm™ tissues were exposed to extracts of three plain polymer samples, and four polymers embedded with known irritant chemicals. Exposures were performed for 18 and 24h. Resulting tissue viability was assessed by MTT reduction and IL-1α release was assessed by ELISA. Testing was also performed using various concentrations of SDS ranging from 0.5 to 1% (w/v). Overall, results were similar for samples tested and 18 and 24h, but the 18h exposure time has the potential to have an impact on the results of some sample types. IL-1α testing was shown to be useful to clarify conflicting tissue viability results. Use of a lower concentration of SDS as a positive control can help prevent issues that arise from excessive tissue damage often caused by 1% SDS. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Double exposure technique for 45nm node and beyond

NASA Astrophysics Data System (ADS)

Hsu, Stephen; Park, Jungchul; Van Den Broeke, Douglas; Chen, J. Fung

2005-11-01

The technical challenges in using F2 lithography for the 45nm node, along with the insurmountable difficulties in EUV lithography, has driven the semiconductor chipmaker into the low k1 lithography era under the pressure of ever decreasing feature sizes. Extending lithography towards lower k1 puts heavy demand on the resolution enhancement technique (RET), exposure tool, and the need for litho friendly design. Hyper numerical aperture (NA) exposure tools, immersion, and double exposure techniques (DET's) are the promising methods to extend lithography manufacturing to the 45nm node at k1 factors below 0.3. Scattering bars (SB's) have become an integral part of the lithography process as chipmakers move to production at ever lower k1 factors. To achieve better critical dimension (CD) control, polarization is applied to enhance the image contrast in the preferential imaging orientation, which increases the risk of SB printability. The optimum SB width is approximately (0.20 ~ 0.25)*(λ/NA). When the SB width becomes less than the exposure wavelength on the 4X mask, Kirchhoff's scalar theory under predicts the SB intensity. The optical weighting factor of the SB increases (Figure 1b) and the SB's become more susceptible to printing. Meanwhile, under hyper NA conditions, the effectiveness of "subresolution" SB's is significantly diminished. A full-sized scattering bars (FSB) scheme becomes necessary. Double exposure methods, such as using ternary 6% attenuated PSM (attPSM) for DDL, are good imaging solutions that can reach and likely go beyond the 45nm node. Today DDL, using binary chrome masks, is capable of printing 65 nm device patterns. In this work, we investigate the use of DET with 6% attPSM masks to target 45nm node device. The SB scalability and printability issues can be taken cared of by using "mutual trimming", i.e., with the combined energy from the two exposures. In this study, we share our findings of using DET to pattern a 45nm node device design with polarization and immersion. We also explore other double patterning methods which in addition to having two exposures, incorporates double coat/developing/etch processing to break the 0.25 k1 barrier.

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

PubMed

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.

Status: Crewmember Noise Exposures on the International Space Station

NASA Technical Reports Server (NTRS)

Limardo-Rodriguez, Jose G.; Allen, Christopher S.; Danielson, Richard W.

2015-01-01

The International Space Station (ISS) provides a unique environment where crewmembers from the US and our international partners work and live for as long as 6 to 12 consecutive months. During these long-durations ISS missions, noise exposures from onboard equipment are posing concerns for human factors and crewmember health risks, such as possible reductions in hearing sensitivity, disruptions of crew sleep, interference with speech intelligibility and voice communications, interference with crew task performance, and reduced alarm audibility. It is crucial to control acoustical noise aboard ISS to acceptable noise exposure levels during the work-time period, and to also provide a restful sleep environment during the sleep-time period. Acoustic dosimeter measurements, obtained when the crewmember wears the dosimeter for 24-hour periods, are conducted onboard ISS every 60 days and compared to ISS flight rules. NASA personnel then assess the acoustic environment to which the crewmembers are exposed, and provide recommendations for hearing protection device usage. The purpose of this paper is to provide an update on the status of ISS noise exposure monitoring and hearing conservation strategies, as well as to summarize assessments of acoustic dosimeter data collected since the Increment 36 mission (April 2013). A description of the updated noise level constraints flight rule, as well as the Noise Exposure Estimation Tool and the Noise Hazard Inventory implementation for predicting crew noise exposures and recommending to ISS crewmembers when hearing protection devices are required, will be described.

Precautionary Practices of Healthcare Workers Who Disinfect Medical and Dental Devices Using High-Level Disinfectants

PubMed Central

Henn, Scott A.; Boiano, James M.; Steege, Andrea L.

2016-01-01

Background High-level disinfectants (HLDs) are used throughout the healthcare industry to chemically disinfect reusable, semicritical medical and dental devices to control and prevent healthcare-associated infections among patient populations. Workers who use HLDs are at risk of exposure to these chemicals, some of which are respiratory and skin irritants and sensitizers. Objective To evaluate exposure controls used and to better understand impediments to healthcare workers using personal protective equipment while handling HLDs. Design Web-based survey. Participants A targeted sample of members of professional practice organizations representing nurses, technologists/technicians, dental professionals, respiratory therapists, and others who reported handling HLDs in the previous 7 calendar days. Participating organizations invited either all or a random sample of members via email, which included a hyperlink to the survey. Methods Descriptive analyses were conducted including simple frequencies and prevalences. Results A total of 4,657 respondents completed the survey. The HLDs used most often were glutaraldehyde (59%), peracetic acid (16%), and ortho-phthalaldehyde (15%). Examples of work practices or events that could increase exposure risk included failure to wear water-resistant gowns (44%); absence of standard procedures for minimizing exposure (19%); lack of safe handling training (17%); failure to wear protective gloves (9%); and a spill/leak of HLD during handling (5%). Among all respondents, 12% reported skin contact with HLDs, and 33% of these respondents reported that they did not always wear gloves. Conclusion Findings indicated that precautionary practices were not always used, underscoring the importance of improved employer and worker training and education regarding HLD hazards. PMID:25633000

Exposure system to study hypotheses of ELF and RF electromagnetic field interactions of mobile phones with the central nervous system.

PubMed

Murbach, Manuel; Christopoulou, Maria; Crespo-Valero, Pedro; Achermann, Peter; Kuster, Niels

2012-09-01

A novel exposure system for double-blind human electromagnetic provocation studies has been developed that satisfies the precision, control of fields and potential artifacts, and provides the flexibility to investigate the response of hypotheses-driven electromagnetic field exposure schemes on brain function, ranging from extremely low frequency (ELF) to radio frequency (RF) fields. The system can provide the same exposure of the lateral cerebral cortex at two different RF frequencies (900 and 2140 MHz) but with different exposure levels at subcortical structures, and also allows uniform ELF magnetic field exposure of the brain. The RF modulation and ELF signal are obtained by a freely programmable arbitrary signal generator allowing a wide range of worst-case exposure scenarios to be simulated, including those caused by wireless devices. The maximum achievable RF exposure is larger than 60 W/kg peak spatial specific absorption rate averaged over 10 g of tissue. The maximum ELF magnetic field exposure of the brain is 800 A/m at 50 Hz with a deviation from uniformity of 8% (SD). Copyright © 2012 Wiley Periodicals, Inc.

Radiation dose distributions due to sudden ejection of cobalt device.

PubMed

Abdelhady, Amr

2016-09-01

The evaluation of the radiation dose during accident in a nuclear reactor is of great concern from the viewpoint of safety. One of important accident must be analyzed and may be occurred in open pool type reactor is the rejection of cobalt device. The study is evaluating the dose rate levels resulting from upset withdrawal of co device especially the radiation dose received by the operator in the control room. Study of indirect radiation exposure to the environment due to skyshine effect is also taken into consideration in order to evaluate the radiation dose levels around the reactor during the ejection trip. Microshield, SHLDUTIL, and MCSky codes were used in this study to calculate the radiation dose profiles during cobalt device ejection trip inside and outside the reactor building. Copyright © 2016 Elsevier Ltd. All rights reserved.

RIR-MAPLE deposition of conjugated polymers and hybrid nanocomposites for application to optoelectronic devices

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

Stiff-Roberts, Adrienne D.; Pate, Ryan; McCormick, Ryan

2012-07-30

Resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) is a variation of pulsed laser deposition that is useful for organic-based thin films because it reduces material degradation by selective absorption of infrared radiation in the host matrix. A unique emulsion-based RIR-MAPLE approach has been developed that reduces substrate exposure to solvents and provides controlled and repeatable organic thin film deposition. In order to establish emulsion-based RIR-MAPLE as a preferred deposition technique for conjugated polymer or hybrid nanocomposite optoelectronic devices, studies have been conducted to demonstrate the value added by the approach in comparison to traditional solution-based deposition techniques, and this workmore » will be reviewed. The control of hybrid nanocomposite thin film deposition, and the photoconductivity in such materials deposited using emulsion-based RIR-MAPLE, will also be reviewed. The overall result of these studies is the demonstration of emulsion-based RIR-MAPLE as a viable option for the fabrication of conjugated polymer and hybrid nanocomposite optoelectronic devices that could yield improved device performance.« less

Laser-based irradiation apparatus and methods for monitoring the dose-rate response of semiconductor devices

DOEpatents

Horn, Kevin M [Albuquerque, NM

2006-03-28

A scanned, pulsed, focused laser irradiation apparatus can measure and image the photocurrent collection resulting from a dose-rate equivalent exposure to infrared laser light across an entire silicon die. Comparisons of dose-rate response images or time-delay images from before, during, and after accelerated aging of a device, or from periodic sampling of devices from fielded operational systems allows precise identification of those specific age-affected circuit structures within a device that merit further quantitative analysis with targeted materials or electrical testing techniques. Another embodiment of the invention comprises a broad-beam, dose rate-equivalent exposure apparatus. The broad-beam laser irradiation apparatus can determine if aging has affected the device's overall functionality. This embodiment can be combined with the synchronized introduction of external electrical transients into a device under test to simulate the electrical effects of the surrounding circuitry's response to a radiation exposure.

Arbitrary shape region-of-interest fluoroscopy system

NASA Astrophysics Data System (ADS)

Xu, Tong; Le, Huy; Molloi, Sabee Y.

2002-05-01

Region-of-interest (ROI) fluoroscopy has previously been investigated as a method to reduce x-ray exposure to the patient and the operator. This ROI fluoroscopy technique allows the operator to arbitrarily determine the shape, size, and location of the ROI. A device was used to generate patient specific x-ray beam filters. The device is comprised of 18 step-motors that control a 16 X 16 matrix of pistons to form the filter from a deformable attenuating material. Patient exposure reductions were measured to be 84 percent for a 65 kVp beam. Operator exposure reduction was measured to be 69 percent. Due to the reduced x-ray scatter, image contrast was improved by 23 percent inside the ROI. The reduced gray level in the periphery was corrected using an experimentally determined compensation ratio. A running average interpolation technique was used to eliminate the artifacts from the ROI edge. As expected, the final corrected images show increased noise in the periphery. However, the anatomical structures in the periphery could still be visualized. This arbitrary shaped region of interest fluoroscopic technique was shown to be effective in terms of its ability to reduce patient and operator exposure without significant reduction in image quality. The ability to define an arbitrary shaped ROI should make the technique more clinically feasible.

Particulate metals and organic compounds from electronic and tobacco-containing cigarettes: comparison of emission rates and secondhand exposure.

PubMed

Saffari, Arian; Daher, Nancy; Ruprecht, Ario; De Marco, Cinzia; Pozzi, Paolo; Boffi, Roberto; Hamad, Samera H; Shafer, Martin M; Schauer, James J; Westerdahl, Dane; Sioutas, Constantinos

2014-01-01

In recent years, electronic cigarettes have gained increasing popularity as alternatives to normal (tobacco-containing) cigarettes. In the present study, particles generated by e-cigarettes and normal cigarettes have been analyzed and the degree of exposure to different chemical agents and their emission rates were quantified. Despite the 10-fold decrease in the total exposure to particulate elements in e-cigarettes compared to normal cigarettes, specific metals (e.g. Ni and Ag) still displayed a higher emission rate from e-cigarettes. Further analysis indicated that the contribution of e-liquid to the emission of these metals is rather minimal, implying that they likely originate from other components of the e-cigarette device or other indoor sources. Organic species had lower emission rates during e-cigarette consumption compared to normal cigarettes. Of particular note was the non-detectable emission of polycyclic aromatic hydrocarbons (PAHs) from e-cigarettes, while substantial emission of these species was observed from normal cigarettes. Overall, with the exception of Ni, Zn, and Ag, the consumption of e-cigarettes resulted in a remarkable decrease in secondhand exposure to all metals and organic compounds. Implementing quality control protocols on the manufacture of e-cigarettes would further minimize the emission of metals from these devices and improve their safety and associated health effects.

The effect of simulated field storage conditions on the accuracy of rapid user-friendly blood pathogen detection kits.

PubMed

Bienek, Diane R; Charlton, David G

2012-05-01

Being able to test for the presence of blood pathogens at forward locations could reduce morbidity and mortality in the field. Rapid, user-friendly blood typing kits for detecting Human Immunodeficiency Virus (HIV), Hepatitis C Virus (HCV), and Hepatitis B Virus (HBV) were evaluated to determine their accuracy after storage at various temperatures/humidities. Rates of positive tests of control groups, experimental groups, and industry standards were compared (Fisher's exact chi2, p < or = 0.05). Compared to the control group, 2 of 10 HIV detection devices were adversely affected by exposure to high temperature/high humidity or high temperature/low humidity. With one exception, none of the environmentally exposed HCV or HBV detection devices exhibited significant differences compared to those stored under control conditions. For HIV, HCV, and HBV devices, there were differences compared to the industry standard. Collectively, this evaluation of pathogen detection kits revealed that diagnostic performance varies among products and storage conditions, and that the tested products cannot be considered to be approved for use to screen blood, plasma, cell, or tissue donors.

Investigation of the Feasibility of an Intervention to Manage Fall Risk in Wheeled Mobility Device Users with Multiple Sclerosis.

PubMed

Rice, Laura A; Isaacs, Zadok; Ousley, Cherita; Sosnoff, Jacob

2018-01-01

Falls are a common concern for wheeled mobility device users with multiple sclerosis (MS); however, no evidence-based fall prevention programs have been developed to meet the specific needs of the population. We examine the preliminary feasibility of a fall management intervention in wheeled mobility device users with MS. Study participants were exposed to an intervention program targeting risk factors for falls, including transfer skills and seated postural control. The feasibility of the program was evaluated by assessing participant perspectives, cost, recruitment rates, study adherence, participant retention, safety, and the ability to collect primary and secondary outcomes, including fall frequency, concerns about falling, transfer quality, and seated postural control. 16 wheeled mobility device users completed the program, which was found to be feasible and was positively evaluated by participants. No adverse events were experienced. After exposure to the intervention, fall frequency significantly decreased (P < .001) and transfer quality (P = .001) and seated postural control (P = .002) significantly improved. No significant differences were found regarding concerns about falling (P = .728). This study examined the feasibility of an intervention program to manage fall risk in wheeled mobility device users with MS. The program was found to be feasible, and preliminary results showed the intervention to be effective in decreasing fall frequency. Additional testing is needed to further examine the efficacy and long-term impact of the intervention.

An Intelligent Catheter System Robotic Controlled Catheter System

PubMed Central

Negoro, M.; Tanimoto, M.; Arai, F.; Fukuda, T.; Fukasaku, K.; Takahashi, I.; Miyachi, S.

2001-01-01

Summary We have developed a novel catheter system, an intelligent catheter system, which is able to control a catheter by an externally-placed controller. This system has made from master-slave mechanism and has following three components; 1) a joy stick as a master (for operators) 2)a catheter controller as a slave (for a patient),3)a micro force sensor as a sensing device. This catheter tele-guiding system has abilities to perform intravascular procedures from the distant places. It may help to reduce the radiation exposures to the operators and also to help train young doctors. PMID:20663387

Radiation exposure to operator and patients during cardiac electrophysiology study, radiofrequency catheter ablation and cardiac device implantation procedures

NASA Astrophysics Data System (ADS)

Lee, C. H.; Cho, J. H.; Park, S. J.; Kim, J. S.; On, Y. K.; Huh, J.

2015-10-01

The purpose of this study was to measure the radiation exposure to operator and patient during cardiac electrophysiology study, radiofrequency catheter ablation and cardiac device implantation procedures and to calculate the allowable number of cases per year. We carried out 9 electrophysiology studies, 40 radiofrequency catheter ablation and 11 cardiac device implantation procedures. To measure occupational radiation dose and dose-area product (DAP), 13 photoluminescence glass dosimeters were placed at eyes (inside and outside lead glass), thyroids (inside and outside thyroid collar), chest (inside and outside lead apron), wrists, genital of the operator (inside lead apron), and 6 of photoluminescence glass dosimeters were placed at eyes, thyroids, chest and genital of the patient. Exposure time and DAP values were 11.7 ± 11.8 min and 23.2 ± 26.2 Gy cm2 for electrophysiology study; 36.5 ± 42.1 min and 822.4 ± 125.5 Gy cm2 for radiofrequency catheter ablation; 16.2 ± 9.3 min and 27.8 ± 16.5 Gy cm2 for cardiac device implantation procedure, prospectively. 4591 electrophysiology studies can be conducted within the occupational exposure limit for the eyes (150 mSv), and 658-electrophysiology studies with radiofrequency catheter ablation can be carried out within the occupational exposure limit for the hands (500 mSv). 1654 cardiac device implantation procedure can be conducted within the occupational exposure limit for the eyes (150 mSv). The amounts of the operator and patient's radiation exposure were comparatively small. So, electrophysiology study, radio frequency catheter ablation and cardiac device implantation procedures are safe when performed with modern equipment and optimized protective radiation protect equipment.

High-speed imaging using CMOS image sensor with quasi pixel-wise exposure

NASA Astrophysics Data System (ADS)

Sonoda, T.; Nagahara, H.; Endo, K.; Sugiyama, Y.; Taniguchi, R.

2017-02-01

Several recent studies in compressive video sensing have realized scene capture beyond the fundamental trade-off limit between spatial resolution and temporal resolution using random space-time sampling. However, most of these studies showed results for higher frame rate video that were produced by simulation experiments or using an optically simulated random sampling camera, because there are currently no commercially available image sensors with random exposure or sampling capabilities. We fabricated a prototype complementary metal oxide semiconductor (CMOS) image sensor with quasi pixel-wise exposure timing that can realize nonuniform space-time sampling. The prototype sensor can reset exposures independently by columns and fix these amount of exposure by rows for each 8x8 pixel block. This CMOS sensor is not fully controllable via the pixels, and has line-dependent controls, but it offers flexibility when compared with regular CMOS or charge-coupled device sensors with global or rolling shutters. We propose a method to realize pseudo-random sampling for high-speed video acquisition that uses the flexibility of the CMOS sensor. We reconstruct the high-speed video sequence from the images produced by pseudo-random sampling using an over-complete dictionary.

Devices for preventing percutaneous exposure injuries caused by needles in healthcare personnel.

PubMed

Reddy, Viraj K; Lavoie, Marie-Claude; Verbeek, Jos H; Pahwa, Manisha

2017-11-14

Percutaneous exposure injuries from devices used for blood collection or for injections expose healthcare workers to the risk of blood borne infections such as hepatitis B and C, and human immunodeficiency virus (HIV). Safety features such as shields or retractable needles can possibly contribute to the prevention of these injuries and it is important to evaluate their effectiveness. To determine the benefits and harms of safety medical devices aiming to prevent percutaneous exposure injuries caused by needles in healthcare personnel versus no intervention or alternative interventions. We searched CENTRAL, MEDLINE, EMBASE, NHSEED, Science Citation Index Expanded, CINAHL, Nioshtic, CISdoc and PsycINFO (until 11 November 2016). We included randomised controlled trials (RCT), controlled before and after studies (CBA) and interrupted time-series (ITS) designs of the effect of safety engineered medical devices on percutaneous exposure injuries in healthcare staff. Two of the authors independently assessed study eligibility and risk of bias and extracted data. We synthesized study results with a fixed-effect or random-effects model meta-analysis where appropriate. We included six RCTs with 1838 participants, two cluster-RCTs with 795 participants and 73,454 patient days, five CBAs with approximately 22,000 participants and eleven ITS with an average of 13.8 data points. These studies evaluated safe modifications of blood collection systems, intravenous (IV) systems, injection systems, multiple devices, sharps containers and legislation on the implementation of safe devices. We estimated the needlestick injury (NSI) rate in the control groups to be about one to five NSIs per 1000 person-years. There were only two studies from low- or middle-income countries. The risk of bias was high in 20 of 24 studies. Safe blood collection systems:We found one RCT that found a safety engineered blood gas syringe having no considerable effect on NSIs (Relative Risk (RR) 0.2, 95% Confidence Interval (95% CI) 0.01 to 4.14, 550 patients, very low quality evidence). In one ITS study, safe blood collection systems decreased NSIs immediately after the introduction (effect size (ES) -6.9, 95% CI -9.5 to -4.2) but there was no further decrease over time (ES -1.2, 95% CI -2.5 to 0.1, very low quality evidence). Another ITS study evaluated an outdated recapping shield, which we did not consider further. Safe Intravenous systemsThere was very low quality evidence in two ITS studies that NSIs were reduced with the introduction of safe IV devices, whereas one RCT and one CBA study provided very low quality evidence of no effect. However, there was moderate quality evidence produced by four other RCT studies that these devices increased the number of blood splashes when the safety system had to be engaged actively (relative risk (RR) 1.6, 95% CI 1.08 to 2.36). In contrast there was low quality evidence produced by two RCTs of passive systems that showed no effect on blood splashes. Yet another RCT produced low quality evidence that a different safe active IV system also decreased the incidence of blood leakages. Safe injection devicesThere was very low quality evidence provided by one RCT and one CBA study showing that introduction of safe injection devices did not considerably change the NSI rate. One ITS study produced low quality evidence showing that the introduction of safe passive injection systems had no effect on NSI rate when compared to safe active injection systems. Multiple safe devicesThere was very low quality evidence from one CBA study and two ITS studies. According to the CBA study, the introduction of multiple safe devices resulted in a decrease in NSI,whereas the two ITS studies found no change. Safety containersOne CBA study produced very low quality evidence showing that the introduction of safety containers decreased NSI. However, two ITS studies evaluating the same intervention found inconsistent results. LegislationThere was low to moderate quality evidence in two ITS studies that introduction of legislation on the use of safety-engineered devices reduced the rate of NSIs among healthcare workers. There was also low quality evidence which showed a decrease in the trend over time for NSI rates.Twenty out of 24 studies had a high risk of bias and the lack of evidence of a beneficial effect could be due to both confounding and bias. This does not mean that these devices are not effective. For safe blood collection systems, we found very low quality evidence of inconsistent effects on NSIs. For safe passive intravenous systems, we found very low quality evidence of a decrease in NSI and a reduction in the incidence of blood leakage events but moderate quality evidence that active systems may increase exposure to blood. For safe injection needles, the introduction of multiple safety devices or the introduction of sharps containers the evidence was inconsistent or there was no clear evidence of a benefit. There was low to moderate quality evidence that introduction of legislation probably reduces NSI rates.More high-quality cluster-randomised controlled studies that include cost-effectiveness measures are needed, especially in countries where both NSIs and blood-borne infections are highly prevalent.

Selected Issues in DoD’s Radio Frequency Identification (RFID) Implementation

DTIC Science & Technology

2006-04-01

Evaluation of human exposure to electromagnetic fields from devices operating in the frequency range 0 Hz to 10 GHz, used in Electronic...standard for human exposure to RF Signal, 3 kHz-300 GHz BS EN 50364 Limitation of human exposure to electromagnetic fields from devices operating in the...Management and DoD Explosives Safety Board, and DoDD 6055.9-STD, DoD Ammunition and Explosives Safety Standards. Exposure of people to electromagnetic

Respiratory Protection Program medical clearance for respirator use

NASA Technical Reports Server (NTRS)

1993-01-01

Background on occupational exposure to various inhalents is discussed including on-site hazard control measures, procedures, physiological effects, and interpretation of results for the medical clearance of employee for use of personal respiratory protection devices. The purpose of the Respiratory Protection Program at LeRC is outlined, and the specifics of the Medical Surveillance Program for Respiratory Protection at LeRC are discussed.

Inhalational and dermal exposures during spray application of biocides.

PubMed

Berger-Preiss, Edith; Boehncke, Andrea; Könnecker, Gustav; Mangelsdorf, Inge; Holthenrich, Dagmar; Koch, Wolfgang

2005-01-01

Data on inhalational and potential dermal exposures during spray application of liquid biocidal products were generated. On the one hand, model experiments with different spraying devices using fluorescent tracers were carried out to investigate the influence of parameters relevant to the exposure (e.g. spraying equipment, nozzle size, direction of application). On the other hand, measurements were performed at selected workplaces (during disinfection operations in food and feed areas; pest control operations for private, public and veterinary hygiene; wood protection and antifouling applications) after application of biocidal products such as Empire 20, Responsar SC, Omexan-forte, Actellic, Perma-forte; Fendona SC, Pyrethrum mist; CBM 8, Aldekol Des 03, TAD CID, Basileum, Basilit. The measurements taken in the model rooms demonstrated dependence of the inhalation exposure on the type of spraying device used, in the following order: "spraying with low pressure" < "airless spraying" < "fogging" indicating that the particle diameter of the released spray droplets is the most important parameter. In addition inhalation exposure was lowest when the spraying direction was downward. Also for the potential dermal exposure, the spraying direction was of particular importance: overhead spraying caused the highest contamination of body surfaces. The data of inhalational and potential dermal exposures gained through workplace measurements showed considerable variation. During spraying procedures with low-pressure equipments, dose rates of active substances inhaled by the operators ranged from 7 to 230 microg active substance (a.s.)/h. An increase in inhaled dose rates (6-33 mg a.s./h) was observed after use of high application volumes/time unit during wood protection applications indoors. Spraying in the veterinary sector using medium-pressure sprayers led to inhaled dose rates between 2 and 24mga.s./h. The highest inhaled dose rates were measured during fogging (114 mg a.s./h) and after-high-pressure applications in the antifouling sector (110-300 mg a.s./h). The potential dermal exposure of spray operators was lowest (dose rates from 0.2 to 7 mg a.s./h) in the areas of food and feed disinfection and private and public hygiene during spraying with low-pressure devices. During fogging, wood protection and antifouling applications, high-potential dermal exposures of the operators were determined. Dermal dose rates varied between 100 and 34,000 mg a.s./h.

Evaluation of Nasal Mucociliary Transport Rate byTc-Macroaggregated Albumin Rhinoscintigraphy in Woodworkers.

PubMed

Dostbil, Zeki; Polat, Cahit; Uysal, Ismail Önder; Bakır, Salih; Karakuş, Askeri; Altındağ, Serdar

2011-01-01

Woodworkers in the furniture industry are exposed to wood dust in their workplaces. The aim of this study is to investigate the effect of occupational wood dust exposure on the nasal mucociliary transport rates (NMTRs) in woodworkers. Twenty five woodworkers and 30 healthy controls were included in this study. Wood dust concentration in workplaces was measured using the sampling device. (99m) Tc-macroaggregated albumin ((99m)Tc-MAA) rhinoscintigraphy was performed, and NMTR was calculated in all cases. In statistical analysis, an independent samples t-test was used to compare NMTR of woodworkers and control subjects. We found that the mean NMTR of the woodworkers was lower than that of the healthy controls. However, there was not a statistically significant difference between them (P = 0.066). In conclusion, our findings suggested that wood dust exposure may not impair nasal mucociliary transport rate in woodworkers employed in joinery workshops.

Evaluation of Nasal Mucociliary Transport Rate by99mTc-Macroaggregated Albumin Rhinoscintigraphy in Woodworkers

PubMed Central

Dostbil, Zeki; Polat, Cahit; Uysal, İsmail Önder; Bakır, Salih; Karakuş, Askeri; Altındağ, Serdar

2011-01-01

Woodworkers in the furniture industry are exposed to wood dust in their workplaces. The aim of this study is to investigate the effect of occupational wood dust exposure on the nasal mucociliary transport rates (NMTRs) in woodworkers. Twenty five woodworkers and 30 healthy controls were included in this study. Wood dust concentration in workplaces was measured using the sampling device. 99m Tc-macroaggregated albumin (99mTc-MAA) rhinoscintigraphy was performed, and NMTR was calculated in all cases. In statistical analysis, an independent samples t-test was used to compare NMTR of woodworkers and control subjects. We found that the mean NMTR of the woodworkers was lower than that of the healthy controls. However, there was not a statistically significant difference between them (P = 0.066). In conclusion, our findings suggested that wood dust exposure may not impair nasal mucociliary transport rate in woodworkers employed in joinery workshops. PMID:21804940

Multidimensional Circadian Monitoring by Wearable Biosensors in Parkinson’s Disease

PubMed Central

Madrid-Navarro, Carlos J.; Escamilla-Sevilla, Francisco; Mínguez-Castellanos, Adolfo; Campos, Manuel; Ruiz-Abellán, Fernando; Madrid, Juan A.; Rol, M. A.

2018-01-01

Parkinson’s disease (PD) is associated with several non-motor symptoms that may precede the diagnosis and constitute a major source of frailty in this population. The digital era in health care has open up new prospects to move forward from the qualitative and subjective scoring for PD with the use of new wearable biosensors that enable frequent quantitative, reliable, repeatable, and multidimensional measurements to be made with minimal discomfort and inconvenience for patients. A cross-sectional study was conducted to test a wrist-worn device combined with machine-learning processing to detect circadian rhythms of sleep, motor, and autonomic disruption, which can be suitable for the objective and non-invasive evaluation of PD patients. Wrist skin temperature, motor acceleration, time in movement, hand position, light exposure, and sleep rhythms were continuously measured in 12 PD patients and 12 age-matched healthy controls for seven consecutive days using an ambulatory circadian monitoring device (ACM). Our study demonstrates that a multichannel ACM device collects reliable and complementary information from motor (acceleration and time in movement) and common non-motor (sleep and skin temperature rhythms) features frequently disrupted in PD. Acceleration during the daytime (as indicative of motor impairment), time in movement during sleep (representative of fragmented sleep) and their ratio (A/T) are the best indexes to objectively characterize the most common symptoms of PD, allowing for a reliable and easy scoring method to evaluate patients. Chronodisruption score, measured by the integrative algorithm known as the circadian function index is directly linked to a low A/T score. Our work attempts to implement innovative technologies based on wearable, multisensor, objective, and easy-to-use devices, to quantify PD circadian rhythms in huge populations over extended periods of time, while controlling at the same time exposure to exogenous circadian synchronizers. PMID:29632508

OVERVIEW, PRACTICAL TIPS AND POTENTIAL PITFALLS OF USING AUTOMATIC EXPOSURE CONTROL IN CT: SIEMENS CARE DOSE 4D.

PubMed

Söderberg, Marcus

2016-06-01

Today, computed tomography (CT) systems routinely use automatic exposure control (AEC), which modulates the tube current. However, for optimal use, there are several aspects of an AEC system that need to be considered. The purpose of this study was to provide an overview of the Siemens CARE Dose 4D AEC system, discuss practical tips and demonstrate potential pitfalls. Two adult anthropomorphic phantoms were examined using two different Siemens CT systems. When optimising the CT radiation dose and image quality, the projection angle of the localiser, patient centring, protocol selection, scanning direction and the use of protective devices requires special attention. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Mobile selected ion flow tube mass spectrometry (SIFT-MS) devices and their use for pollution exposure monitoring in breath and ambient air-pilot study.

PubMed

Storer, Malina; Salmond, Jennifer; Dirks, Kim N; Kingham, Simon; Epton, Michael

2014-09-01

Studies of health effects of air pollution exposure are limited by inability to accurately determine dose and exposure of air pollution in field trials. We explored the feasibility of using a mobile selected ion flow tube mass spectrometry (SIFT-MS) device, housed in a van, to determine ambient air and breath levels of benzene, xylene and toluene following exercise in areas of high motor vehicle traffic. The breath toluene, xylene and benzene concentration of healthy subjects were measured before and after exercising close to a busy road. The concentration of the volatile organic compounds (VOCs), in ambient air were also analysed in real time. Exercise close to traffic pollution is associated with a two-fold increase in breath VOCs (benzene, xylene and toluene) with levels returning to baseline within 20 min. This effect is not seen when exercising away from traffic pollution sources. Situating the testing device 50 m from the road reduced any confounding due to VOCs in the inspired air prior to the breath testing manoeuvre itself. Real-time field testing for air pollution exposure is possible using a mobile SIFT-MS device. This device is suitable for exploring exposure and dose relationships in a number of large scale field test scenarios.

KENNEDY SPACE CENTER, FLA. - Dr. Paul Hintze (left) explains to Center Director Jim Kennedy a project he is working at the KSC Beach Corrosion Test Site. Hitze is doing post-graduate work for the National Research Council. The test facility site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

NASA Image and Video Library

2003-08-21

KENNEDY SPACE CENTER, FLA. - Dr. Paul Hintze (left) explains to Center Director Jim Kennedy a project he is working at the KSC Beach Corrosion Test Site. Hitze is doing post-graduate work for the National Research Council. The test facility site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

KENNEDY SPACE CENTER, FLA. - Louis MacDowell (right), Testbed manager, explains to Center Director Jim Kennedy the use of astmospheric calibration specimens. Placed at various locations, they can rank the corrosivity of the given environment. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

NASA Image and Video Library

2003-08-21

KENNEDY SPACE CENTER, FLA. - Louis MacDowell (right), Testbed manager, explains to Center Director Jim Kennedy the use of astmospheric calibration specimens. Placed at various locations, they can rank the corrosivity of the given environment. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

Teratogenic effects of Silastic intrauterine devices in the rat with or without added medroxyprogesterone acetate.

PubMed

Barlow, S M; Knight, A F

1983-02-01

The teratogenicity of intrauterine devices (IUDs) made of silicone rubber (Silastic, Dow Corning Corporation, Midland, MI) with or without added medroxyprogesterone acetate (MPA) has been investigated in the rat. Small rod-shaped IUDs were inserted into the uterus, one between each embryo, on day 9 of pregnancy and left in place until the rats were killed just before term for examination of the fetuses. MPA exposure caused masculinization of the external genitalia of female fetuses and feminization of the external genitalia of male fetuses. There was no increase in other, nongenital malformations in MPA-exposed fetuses, compared with fetuses exposed to Silastic alone, but both Silastic-exposed groups had significantly more malformations than untreated control rats. In a second experiment, a significant increase in malformations in fetuses exposed to Silastic alone, compared with untreated control fetuses, was confirmed. The malformation rate in control rats that underwent sham operations was not significantly increased, compared with untreated control rats.

Methodological considerations in observational comparative effectiveness research for implantable medical devices: an epidemiologic perspective.

PubMed

Jalbert, Jessica J; Ritchey, Mary Elizabeth; Mi, Xiaojuan; Chen, Chih-Ying; Hammill, Bradley G; Curtis, Lesley H; Setoguchi, Soko

2014-11-01

Medical devices play a vital role in diagnosing, treating, and preventing diseases and are an integral part of the health-care system. Many devices, including implantable medical devices, enter the market through a regulatory pathway that was not designed to assure safety and effectiveness. Several recent studies and high-profile device recalls have demonstrated the need for well-designed, valid postmarketing studies of medical devices. Medical device epidemiology is a relatively new field compared with pharmacoepidemiology, which for decades has been developed to assess the safety and effectiveness of medications. Many methodological considerations in pharmacoepidemiology apply to medical device epidemiology. Fundamental differences in mechanisms of action and use and in how exposure data are captured mean that comparative effectiveness studies of medical devices often necessitate additional and different considerations. In this paper, we discuss some of the most salient issues encountered in conducting comparative effectiveness research on implantable devices. We discuss special methodological considerations regarding the use of data sources, exposure and outcome definitions, timing of exposure, and sources of bias. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Sperm studies in anesthesiologists

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

Wyrobek, A.J.; Brodsky, J.; Gordon, l.

1981-11-01

Semen samples were collected from 46 anesthesiologists each of whom had worked a minimum of one year in hospital operating rooms ventilated with modern gas-scavenging devices. Samples collected from 26 beginning residents in anesthesiology served as controls. Concentrations of sperm and percentage of sperm having abnormal head shapes were determined for each sample. No significant differences were found between anesthesiologists and beginning residents. Limiting the analyses to men having no confounding factors (varicocele, recent illness, medications, heavy smoking, frequent sauna use) did not change the results. The sperm concentration and morphology in 13 men did not change signficantly after onemore » year of exposure to anesthetic gases. However, the group of men who had one or more confounding factors (excluding exposure to anesthetic gases) showed significantly higher percentages of sperm abnormalities than did the group of men without such factors. These results suggest that limited exposure to anesthetic gases does not significantly affect sperm production as judged by changes in sperm concentration and morphology. These data are reassuring, but since the hospitals surveyed used modern gas-scavenging devices, men who are occupationally exposed to anesthetic gases without this protection should be studied for fuller assessment of the possible human spermatotoxic effects.« less

A spatiotemporally controllable chemical gradient generator via acoustically oscillating sharp-edge structures.

PubMed

Huang, Po-Hsun; Chan, Chung Yu; Li, Peng; Nama, Nitesh; Xie, Yuliang; Wei, Cheng-Hsin; Chen, Yuchao; Ahmed, Daniel; Huang, Tony Jun

2015-11-07

The ability to generate stable, spatiotemporally controllable concentration gradients is critical for resolving the dynamics of cellular response to a chemical microenvironment. Here we demonstrate an acoustofluidic gradient generator based on acoustically oscillating sharp-edge structures, which facilitates in a step-wise fashion the rapid mixing of fluids to generate tunable, dynamic chemical gradients. By controlling the driving voltage of a piezoelectric transducer, we demonstrated that the chemical gradient profiles can be conveniently altered (spatially controllable). By adjusting the actuation time of the piezoelectric transducer, moreover, we generated pulsatile chemical gradients (temporally controllable). With these two characteristics combined, we have developed a spatiotemporally controllable gradient generator. The applicability and biocompatibility of our acoustofluidic gradient generator are validated by demonstrating the migration of human dermal microvascular endothelial cells (HMVEC-d) in response to a generated vascular endothelial growth factor (VEGF) gradient, and by preserving the viability of HMVEC-d cells after long-term exposure to an acoustic field. Our device features advantages such as simple fabrication and operation, compact and biocompatible device, and generation of spatiotemporally tunable gradients.

Toxicity of spray and fumigant products containing cassia oil to Dermatophagoides farinae and Dermatophagoides pteronyssinus (Acari: Pyroglyphidae).

PubMed

Kim, Soon-Ii; Kim, Hyun-Kyung; Koh, Young-Yull; Clark, J Marshall; Ahn, Young-Joon

2006-08-01

The toxicity of formulations of oil of cassia, Cinnamomum cassia Blume, (20 and 50 g L(-1) sprays and 100% oil-based fumigant) to adult Dermatophagoides farinae Hughes and D. pteronyssinus Trouessart was examined using contact and vapour-phase toxicity bioassays. Results were compared with the lethal activity of three commercial acaricides: benzyl benzoate, dibutyl phthalate and diethyl-m-toluamide (deet). The contact toxicity of cassia oil to both dust mite species was comparable with that of benzyl benzoate but was higher than that of the other two acaricides. Sprays containing 20 and 50 g L(-1) cassia oil were effective against both mite species when applied to fabric, glass, paper, plastic, tin or wood substrates. Applications of the 50 g L(-1) spray to different space volumes and surface areas determined that 50-60 mg of cassia oil was needed to control dust mites in 3.4 m(3) or in 1 m(2). In tests with fumigant devices, toxicity varied according to the thickness of non-woven fabric covering the device, the exposure time, the number of fumigant devices used and the volume of the space sprayed. Fumigant toxicity to adult D. pteronyssinus was more pronounced with devices enclosed in thinner (40 microm) versus thicker (45 or 50 microm) non-woven fabric covers. A single fumigant device with a 40 microm thick non-woven fabric cover resulted in substantial control in a space of 0.05 m(3) but exhibited only moderate to weak control in spaces >or= 0.097 m(3) at 4 days after application. Two fumigant devices gave 88% mortality in a space of 1.73 m(3). Cassia oil applied as sprays or in fumigant devices appears to provide effective protection of humans from house dust mites.

Ionic Transport through Chemically Functionalized Hydrogen Peroxide-Sensitive Asymmetric Nanopores.

PubMed

Ali, Mubarak; Ahmed, Ishtiaq; Nasir, Saima; Ramirez, Patricio; Niemeyer, Christof M; Mafe, Salvador; Ensinger, Wolfgang

2015-09-09

We describe the fabrication of a chemical-sensitive nanofluidic device based on asymmetric nanopores whose transport characteristics can be modulated upon exposure to hydrogen peroxide (H2O2). We show experimentally and theoretically that the current-voltage curves provide a suitable method to monitor the H2O2-mediated change in pore surface characteristics from the electronic readouts. We demonstrate also that the single pore characteristics can be scaled to the case of a multipore membrane whose electric outputs can be readily controlled. Because H2O2 is an agent significant for medical diagnostics, the results should be useful for sensing nanofluidic devices.

Natural vacuum electronics

NASA Technical Reports Server (NTRS)

Leggett, Nickolaus

1990-01-01

The ambient natural vacuum of space is proposed as a basis for electron valves. Each valve is an electron controlling structure similiar to a vacuum tube that is operated without a vacuum sustaining envelope. The natural vacuum electron valves discussed offer a viable substitute for solid state devices. The natural vacuum valve is highly resistant to ionizing radiation, system generated electromagnetic pulse, current transients, and direct exposure to space conditions.

Microgravity Simulation Facility (MSF)

NASA Technical Reports Server (NTRS)

Richards, Stephanie E. (Compiler); Levine, Howard G.; Zhang, Ye

2016-01-01

The Microgravity Simulator Facility (MSF) at Kennedy Space Center (KSC) was established to support visiting scientists for short duration studies utilizing a variety of microgravity simulator devices that negate the directional influence of the "g" vector (providing simulated conditions of micro or partial gravity). KSC gravity simulators can be accommodated within controlled environment chambers allowing investigators to customize and monitor environmental conditions such as temperature, humidity, CO2, and light exposure.

Effects of Bluetooth device electromagnetic field on hearing: pilot study.

PubMed

Balachandran, R; Prepageran, N; Prepagaran, N; Rahmat, O; Zulkiflee, A B; Hufaida, K S

2012-04-01

The Bluetooth wireless headset has been promoted as a 'hands-free' device with a low emission of electromagnetic radiation. To evaluate potential changes in hearing function as a consequence of using Bluetooth devices, by assessing changes in pure tone audiography and distortion production otoacoustic emissions. Prospective study. Thirty adult volunteers were exposed to a Bluetooth headset device (1) on 'standby' setting for 6 hours and (2) at full power for 10 minutes. Post-exposure hearing was evaluated using pure tone audiography and distortion production otoacoustic emission testing. There were no statistically significant changes in hearing, as measured above, following either exposure type. Exposure to the electromagnetic field emitted by a Bluetooth headset, as described above, did not decrease hearing thresholds or alter distortion product otoacoustic emissions.

Conservative Exposure Predictions for Rapid Risk Assessment of Phase-Separated Additives in Medical Device Polymers.

PubMed

Chandrasekar, Vaishnavi; Janes, Dustin W; Saylor, David M; Hood, Alan; Bajaj, Akhil; Duncan, Timothy V; Zheng, Jiwen; Isayeva, Irada S; Forrey, Christopher; Casey, Brendan J

2018-01-01

A novel approach for rapid risk assessment of targeted leachables in medical device polymers is proposed and validated. Risk evaluation involves understanding the potential of these additives to migrate out of the polymer, and comparing their exposure to a toxicological threshold value. In this study, we propose that a simple diffusive transport model can be used to provide conservative exposure estimates for phase separated color additives in device polymers. This model has been illustrated using a representative phthalocyanine color additive (manganese phthalocyanine, MnPC) and polymer (PEBAX 2533) system. Sorption experiments of MnPC into PEBAX were conducted in order to experimentally determine the diffusion coefficient, D = (1.6 ± 0.5) × 10 -11  cm 2 /s, and matrix solubility limit, C s  = 0.089 wt.%, and model predicted exposure values were validated by extraction experiments. Exposure values for the color additive were compared to a toxicological threshold for a sample risk assessment. Results from this study indicate that a diffusion model-based approach to predict exposure has considerable potential for use as a rapid, screening-level tool to assess the risk of color additives and other small molecule additives in medical device polymers.

Response of Caenorhabditis elegans to wireless devices radiation exposure.

PubMed

Fasseas, Michael K; Fragopoulou, Adamantia F; Manta, Areti K; Skouroliakou, Aikaterini; Vekrellis, Konstantinos; Margaritis, Lukas H; Syntichaki, Popi

2015-03-01

To examine the impact of electromagnetic radiation, produced by GSM (Global System for Mobile communications) mobile phones, Wi-Fi (Wireless-Fidelity) routers and wireless DECT (Digital Enhanced Cordless Telecommunications) phones, on the nematode Caenorhabditis elegans. We exposed synchronized populations, of different developmental stages, to these wireless devices at E-field levels below ICNIRP's (International Commission on Non-Ionizing Radiation Protection) guidelines for various lengths of time. WT (wild-type) and aging- or stress-sensitive mutant worms were examined for changes in growth, fertility, lifespan, chemotaxis, short-term memory, increased ROS (Reactive Oxygen Species) production and apoptosis by using fluorescent marker genes or qRT-PCR (quantitative Reverse Transcription-Polymerase Chain Reaction). No statistically significant differences were found between the exposed and the sham/control animals in any of the experiments concerning lifespan, fertility, growth, memory, ROS, apoptosis or gene expression. The worm appears to be robust to this form of (pulsed) radiation, at least under the exposure conditions used.

Understanding the effects of electromagnetic field emissions from Marine Renewable Energy Devices (MREDs) on the commercially important edible crab, Cancer pagurus (L.).

PubMed

Scott, Kevin; Harsanyi, Petra; Lyndon, Alastair R

2018-06-01

The effects of simulated electromagnetic fields (EMF), emitted from sub-sea power cables, on the commercially important decapod, edible crab (Cancer pagurus), were assessed. Stress related parameters were measured (l-Lactate, d-Glucose, Haemocyanin and respiration rate) along with behavioural and response parameters (antennular flicking, activity level, attraction/avoidance, shelter preference and time spent resting/roaming) during 24-h periods. Exposure to EMF had no effect on Haemocyanin concentrations, respiration rate, activity level or antennular flicking rate. EMF exposure significantly disrupted haemolymph l-Lactate and d-Glucose natural circadian rhythms. Crabs showed a clear attraction to EMF exposed shelter (69%) compared to control shelter (9%) and significantly reduced their time spent roaming by 21%. Consequently, EMF emitted from Marine Renewable Energy Devices (MREDs) will likely affect edible crabs both behaviourally and physiologically, suggesting that the impact of EMF on crustaceans must be considered when planning MREDs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Second-hand smoke exposure generated by new electronic devices (IQOS® and e-cigs) and traditional cigarettes: submicron particle behaviour in human respiratory system.

PubMed

Protano, C; Manigrasso, M; Avino, P; Sernia, S; Vitali, M

2016-01-01

Passive exposure profiles to submicronic particles (SMPs, 5.6-560 nm) of traditional cigarettes and new electronic commercial devices (e-cig and IQOS®, a new heat-not-burn smoking device) were compared. During smoking, SMPs released by traditional cigarettes resulted four-times higher than those released by electronic and heat-not-burn devices and remained high for at least one hour, while SMPs values returned immediately similar to background for electronic and heat-not-burn devices. In all experiments, approximately half of SMPs resulted so small to reach the alveolar region.

Electromagnetic exposure in a phantom in the near and far fields of wire and planar antennas

NASA Astrophysics Data System (ADS)

Mazady, Md. Anas Boksh

Due to the wide availability and usage of wireless devices and systems there have been and are concerns regarding their effects on the human body. Respective regulatory agencies have developed safety standards based on scientific research on electromagnetic (EM) exposure from wireless devices and antennas. The metric that quantifies the exposure level is called the Specific Absorption Rate (SAR). Wireless devices must satisfy the regulatory standards before being marketed. In the past, researchers have primarily focused on investigating the EM exposure from wireless devices that are used very near to the user's head or body (less than 25 mm). But as time progressed many more wireless devices have become ubiquitous (vehicular wireless devices, laptop PCMCIA cards, Bluetooth dongles, wireless LAN routers, cordless phone base stations, and pico base stations are to name a few) and are operated at distances greater than 25 mm yet smaller than 200 mm. Given the variations in operating frequency, distance, and antenna size and type it is challenging to develop an approach using which EM exposure from a wide variety of wireless devices can be evaluated. The problem becomes more involved owing to the difficulties in identifying the antenna zone boundaries, e.g. reactive near-field, radiating near-field, far-field etc. The focus of this thesis is to investigate a large class of low and highly directive antennas and evaluate the EM exposure from them into a large elliptical phantom. The objective is to be able to predict threshold power levels that meet the SAR limits imposed by the regulatory agencies. It was observed that among the low directivity antennas at close near-field distances, electrically small antennas induced distinguishably higher SAR than electrically larger antennas. But differences in SAR were small as the phantom moved into the far-fields of the antennas. SAR induced by highly directive antennas were higher when the phantom was in the far-field of the antennas and was facing the antenna frontal plane. The same was not true when the phantom was in the near-field of the antennas. Finally, by analyzing the simulation and measurement data threshold power formulas were developed for low directivity antennas using which power levels corresponding to the safe exposure limits independent of device type or geometry can be estimated.

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

PubMed

Obajuluwa, Adejoke Olukayode; Akinyemi, Ayodele Jacob; Afolabi, Olakunle Bamikole; Adekoya, Khalid; Sanya, Joseph Olurotimi; Ishola, Azeez Olakunle

2017-01-01

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.

Performance Assessment of Communication Enhancement Devices TEA HI Threat Headset

DTIC Science & Technology

2015-08-01

while mitigating hearing loss and tinnitus caused by exposure to loud, steady-state and impulsive noise. Active devices should theoretically have...mitigating hearing loss and tinnitus caused by exposure to loud, steady-state and impulsive noise. The general approach for this assessment was to use

Laser-based irradiation apparatus and method to measure the functional dose-rate response of semiconductor devices

DOEpatents

Horn, Kevin M [Albuquerque, NM

2008-05-20

A broad-beam laser irradiation apparatus can measure the parametric or functional response of a semiconductor device to exposure to dose-rate equivalent infrared laser light. Comparisons of dose-rate response from before, during, and after accelerated aging of a device, or from periodic sampling of devices from fielded operational systems can determine if aging has affected the device's overall functionality. The dependence of these changes on equivalent dose-rate pulse intensity and/or duration can be measured with the apparatus. The synchronized introduction of external electrical transients into the device under test can be used to simulate the electrical effects of the surrounding circuitry's response to a radiation exposure while exposing the device to dose-rate equivalent infrared laser light.

Impact of Daily Noise Exposure Monitoring on Occupational Noise Exposures in Manufacturing Workers

PubMed Central

McTague, Michael F.; Galusha, Deron; Dixon-Ernst, Christine; Kirsche, Sharon R.; Slade, Martin D.; Cullen, Mark R.; Rabinowitz, Peter M.

2013-01-01

Objective Despite the use of hearing protective devices (HPDs), noise induced hearing loss (NIHL) remains one of the most prevalent occupational conditions. A new technology allows for daily monitoring of noise exposures under HPDs. We report on an intervention employing the voluntary use of this technology in a worksite setting. Design Volunteers were fitted with a device allowing them to monitor noise exposure under their hearing protection on a daily basis. The trends in noise exposures for individuals who completed at least six months of the intervention were analyzed. Study Sample Recruitment occurred at three manufacturing facilities, with 127 workers enrolling and 66 workers actively using the device during their work shifts. Results Among volunteers downloading regularly, the percentage of daily exposures in excess of the OSHA action level (85dBA) decreased from 14% to 8%, while the percentage of daily exposures in excess of 90dBA decreased from 4% to less than 2%. Conclusion Initial results from this longitudinal study indicate that volunteers find daily noise exposure monitoring to be feasible, and that workers who monitor daily are able to reduce exposures. The results of subject adherence shed light on the challenges and possibilities of worksite interventions for health and safety. PMID:23373740

Passive exposure to electronic cigarette (e-cigarette) use increases desire for combustible and e-cigarettes in young adult smokers

PubMed Central

King, Andrea C; Smith, Lia J; McNamara, Patrick J; Matthews, Alicia K; Fridberg, Daniel J

2016-01-01

Background Passive exposure to combustible cigarette use has been shown to act as a cue to increase smoking urge. Given the resemblance of e-cigarettes and other electronic nicotine delivery systems (ENDS) to combustible cigarettes, we examined whether these devices could also act as a cue to increase smoking desire and urges in those passively exposed. Methods Young adult daily smokers (age 18–35 years; N=60) completed subjective ratings before and after exposure to a study confederate drinking bottled water (control cue) and then smoking either a combustible or e-cigarette (active cue). Smoking desire and urge ratings were measured with visual analogue scale items for desire for a regular and an e-cigarette and the Brief Questionnaire of Smoking Urges. Results Passive exposure to both the e-cigarette and combustible cigarette cue significantly increased observers’ ratings of desire and urge to smoke a regular cigarette (all ps<0.05). Exposure to the e-cigarette cue but not the regular cigarette cue also increased desire to smoke an e-cigarette (p<0.01). Conclusions The results provide the first evidence in a controlled setting that electronic cigarette exposure may evoke smoking urges in young adult daily smokers. With replication, these findings may have relevance for ENDS regulation and policy. PMID:24848637

Controlled power delivery for super-resolution imaging of biological samples using digital micromirror device

NASA Astrophysics Data System (ADS)

Valiya Peedikakkal, Liyana; Cadby, Ashley

2017-02-01

Localization based super resolution images of a biological sample is generally achieved by using high power laser illumination with long exposure time which unfortunately increases photo-toxicity of a sample, making super resolution microscopy, in general, incompatible with live cell imaging. Furthermore, the limitation of photobleaching reduces the ability to acquire time lapse images of live biological cells using fluorescence microscopy. Digital Light Processing (DLP) technology can deliver light at grey scale levels by flickering digital micromirrors at around 290 Hz enabling highly controlled power delivery to samples. In this work, Digital Micromirror Device (DMD) is implemented in an inverse Schiefspiegler telescope setup to control the power and pattern of illumination for super resolution microscopy. We can achieve spatial and temporal patterning of illumination by controlling the DMD pixel by pixel. The DMD allows us to control the power and spatial extent of the laser illumination. We have used this to show that we can reduce the power delivered to the sample to allow for longer time imaging in one area while achieving sub-diffraction STORM imaging in another using higher power densities.

Temperature-controlled laminar airflow in severe asthma for exacerbation reduction (The LASER Trial): study protocol for a randomised controlled trial.

PubMed

Storrar, Will; Fogg, Carole; Brown, Tom; Dennison, Paddy; Yu, Ly-Mee; Dewey, Ann; Luengo-Fernandez, Ramon; Dean, Tara; Rahman, Najib; Mansur, Adel; Howarth, Peter H; Bradding, Peter; Chauhan, Anoop J

2016-01-08

Asthma affects more than 5 million patients in the United Kingdom. Nearly 500,000 of these patients have severe asthma with severe symptoms and frequent exacerbations that are inadequately controlled with available treatments. The burden of severe asthma on the NHS is enormous, accounting for 80 % of the total asthma cost (£1 billion), with frequent exacerbations and expensive medications generating much of this cost. Of those patients with severe asthma, 70 % are sensitised to indoor aeroallergens, and the level of exposure to allergens determines the symptoms; patients exposed to high levels are therefore most at risk of exacerbations and hospital admissions. The LASER trial aims to assess whether a new treatment, temperature controlled laminar airflow (TLA) delivered by the Airsonett™ device, can reduce the frequency of exacerbations in patients with severe allergic asthma by reducing exposure to aeroallergens overnight. This multicentre study is a placebo-controlled, blinded, randomised controlled, parallel group trial. A total of 222 patients with a new or current diagnosis of severe allergic asthma will be assigned with a random element in a 1:1 ratio to receive either an active device for one year or a placebo device. The primary outcome is the frequency of severe asthma exacerbations occurring over a 12-month period, defined in accordance with the American Thoracic Society/European Respiratory Society (ATS/ERS) guidelines. Secondary outcomes include changes in asthma control, lung function, asthma-specific and global quality of life for participants and their carers, adherence to intervention, healthcare resource use and costs, and cost-effectiveness. Qualitative interviews will be conducted to elicit participant's and their partner's perceptions of the treatment. Effective measures of allergen avoidance have, to date, proved elusive. The LASER trial aims to address this. The study will ascertain whether home-based nocturnal TLA usage over a 12-month period can reduce the frequency of exacerbations and improve asthma control and quality of life as compared to placebo, whilst being cost-effective and acceptable to adults with poorly controlled, severe allergic asthma. The results of this study will be widely applicable to the many patients with allergic asthma both in the UK and internationally. Current controlled trials ISRCTN46346208 (Date assigned 22 January 2014).

Possible long term effects of chemical warfare using visual evoked potentials.

PubMed

Riazi, Abbas; Hafezi, Rhamatollah; Babaei, Mahmoud; Naderi, Mostafa

2014-09-01

Some studies have already addressed the effects of occupational organic solvent exposure on the visually evoked potentials (VEPs). Visual system is an important target for Sulphur Mustard (SM) toxicity. A number of Iranian victims of Sulphur Mustard (SM) agent were apprehensive about the delay effect of SM on their vision and a possible delay effect of SM on their visual cortex. This investigation was performed on 34 individuals with a history of chemical exposure and a control group of 15 normal people. The Toennies electro-diagnosis device was used and its signals were saved as the latencies. The mean of N75, N140 and P100 of victims of chemical warfare (VCWs) and control group indicated no significant results (P>0.05). The VCWs did not show any visual symptoms and there was no clear deficit in their VEPs.

Impact of nanoparticles on human and environment: review of toxicity factors, exposures, control strategies, and future prospects.

PubMed

Sajid, Muhammad; Ilyas, Muhammad; Basheer, Chanbasha; Tariq, Madiha; Daud, Muhammad; Baig, Nadeem; Shehzad, Farrukh

2015-03-01

Nanotechnology has revolutionized the world through introduction of a unique class of materials and consumer products in many arenas. It has led to production of innovative materials and devices. Despite of their unique advantages and applications in domestic and industrial sectors, use of materials with dimensions in nanometers has raised the issue of safety for workers, consumers, and human environment. Because of their small size and other unique characteristics, nanoparticles have ability to harm human and wildlife by interacting through various mechanisms. We have reviewed the characteristics of nanoparticles which form the basis of their toxicity. This paper also reviews possible routes of exposure of nanoparticles to human body. Dermal contact, inhalation, and ingestion have been discussed in detail. As very limited data is available for long-term human exposures, there is a pressing need to develop the methods which can determine short and long-term effects of nanoparticles on human and environment. We also discuss in brief the strategies which can help to control human exposures to toxic nanoparticles. We have outlined the current status of toxicological studies dealing with nanoparticles, accomplishments, weaknesses, and future challenges.

Potential Sources of Bisphenol A in the Neonatal Intensive Care Unit

PubMed Central

Mendonca, Kaitlin; Hauser, Russ; Calafat, Antonia M.; Ye, Xiaoyun; Meeker, John D.; Ackerman, Robin; Cullinane, Judi; Faller, Josephine; Ringer, Steven

2013-01-01

OBJECTIVES: To determine whether nutritional intake and medical devices are bisphenol A (BPA) exposure sources among premature infants in the NICU. METHODS: Mothers and their premature infants cared for in the NICU for the past 3 days were recruited for this exposure assessment study. Forty-three mothers contributed 1 nutrition sample (breast milk or formula) to characterize the infant’s intake. Two urine samples (before and after feeding) were collected from each of 55 infants. Medical device use was categorized as “low” or “high” based on the number and invasiveness of devices used. BPA urinary concentrations used as a biomarker to estimate BPA exposure were measured by online solid-phase extraction, high performance liquid chromatography, isotope dilution, tandem mass spectrometry. Nonparametric equivalence tests, intraclass correlations, and hierarchical linear mixed-effects models were conducted. RESULTS: Breast milk and formula samples did not differ in total BPA concentration nor did infants’ median urinary concentration of total BPA before or after feedings. However, the median urinary total BPA concentration among infants who required the use of 4 or more medical devices in the past 3 days was significantly higher (36.6 µg/L) than among infants who required the use of 0 to 3 devices (13.9 µg/L). The calculated BPA exposures are lower than the US Environmental Protection Agency reference dose, but considerably higher (16- to 32-fold) than among infants or children from the general population. CONCLUSIONS: The number of medical devices used in the past 3 days, but not nutritional intake, was positively associated with exposure to BPA. PMID:23420909

10 CFR 34.23 - Locking of radiographic exposure devices, storage containers and source changers.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Locking of radiographic exposure devices, storage containers and source changers. 34.23 Section 34.23 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment...

10 CFR 34.23 - Locking of radiographic exposure devices, storage containers and source changers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Locking of radiographic exposure devices, storage containers and source changers. 34.23 Section 34.23 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment...

10 CFR 34.23 - Locking of radiographic exposure devices, storage containers and source changers.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Locking of radiographic exposure devices, storage containers and source changers. 34.23 Section 34.23 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment...

10 CFR 34.23 - Locking of radiographic exposure devices, storage containers and source changers.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Locking of radiographic exposure devices, storage containers and source changers. 34.23 Section 34.23 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment...

10 CFR 34.23 - Locking of radiographic exposure devices, storage containers and source changers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Locking of radiographic exposure devices, storage containers and source changers. 34.23 Section 34.23 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment...

Got Mercury?

NASA Technical Reports Server (NTRS)

Meyers, Valerie E.; McCoy, J. Torin; Garcia, Hector D.; James, John T.

2009-01-01

Many of the operational and payload lighting units used in various spacecraft contain elemental mercury. If these devices were damaged on-orbit, elemental mercury could be released into the cabin. Although there are plans to replace operational units with alternate light sources, such as LEDs, that do not contain mercury, mercury-containing lamps efficiently produce high quality illumination and may never be completely replaced on orbit. Therefore, exposure to elemental mercury during spaceflight will remain possible and represents a toxicological hazard. Elemental mercury is a liquid metal that vaporizes slowly at room temperature. However, it may be completely vaporized at the elevated operating temperatures of lamps. Although liquid mercury is not readily absorbed through the skin or digestive tract, mercury vapors are efficiently absorbed through the respiratory tract. Therefore, the amount of mercury in the vapor form must be estimated. For mercury releases from lamps that are not being operated, we utilized a study conducted by the New Jersey Department of Environmental Quality to calculate the amount of mercury vapor expected to form over a 2-week period. For longer missions and for mercury releases occurring when lamps are operating, we conservatively assumed complete volatilization of the available mercury. Because current spacecraft environmental control systems are unable to remove mercury vapors, both short-term and long-term exposures to mercury vapors are possible. Acute exposure to high concentrations of mercury vapors can cause irritation of the respiratory tract and behavioral symptoms, such as irritability and hyperactivity. Chronic exposure can result in damage to the nervous system (tremors, memory loss, insomnia, etc.) and kidneys (proteinurea). Therefore, the JSC Toxicology Group recommends that stringent safety controls and verifications (vibrational testing, etc.) be applied to any hardware that contains elemental mercury that could yield airborne mercury vapor concentrations greater than 0.1 mg/cu m in the total spacecraft atmosphere for exposures lasting 30 days or less or 0.01 mg/cu m mercury vapor for exposures lasting more than 30 days. We also encourage the use of alternative devices that do not contain mercury.

Rare earth elements in human and animal health: State of art and research priorities.

PubMed

Pagano, Giovanni; Aliberti, Francesco; Guida, Marco; Oral, Rahime; Siciliano, Antonietta; Trifuoggi, Marco; Tommasi, Franca

2015-10-01

A number of applications have been developed using rare earth elements (REE), implying several human exposures and raising unsolved questions as to REE-associated health effects. A MedLine survey was retrieved from early reports (1980s) up to June 2015, focused on human and animal exposures to REE. Literature from animal models was selected focusing on REE-associated health effects. Some REE occupational exposures, in jobs such as glass polishers, photoengravers and movie projectionists showed a few case reports on health effects affecting the respiratory system. No case-control or cohort studies of occupational REE exposures were retrieved. Environmental exposures have been biomonitored in populations residing in REE mining areas, showing REE accumulation. The case for a iatrogenic REE exposure was raised by the use of gadolinium-based contrast agents for nuclear magnetic resonance. Animal toxicity studies have shown REE toxicity, affecting a number of endpoints in liver, lungs and blood. On the other hand, the use of REE as feed additives in livestock is referred as a safe and promising device in zootechnical activities, possibly suggesting a hormetic effect both known for REE and for other xenobiotics. Thus, investigations on long-term exposures and observations are warranted. The state of art provides a limited definition of the health effects in occupationally or environmentally REE-exposed human populations. Research priorities should be addressed to case-control or cohort studies of REE-exposed humans and to life-long animal experiments. Copyright © 2015 Elsevier Inc. All rights reserved.

Mobile-phone radiation-induced perturbation of gene-expression profiling, redox equilibrium and sporadic-apoptosis control in the ovary of Drosophila melanogaster

PubMed Central

Manta, Areti K.; Papadopoulou, Deppie; Polyzos, Alexander P.; Fragopoulou, Adamantia F.; Skouroliakou, Aikaterini S.; Thanos, Dimitris; Stravopodis, Dimitrios J.; Margaritis, Lukas H.

2017-01-01

ABSTRACT The daily use by people of wireless communication devices has increased exponentially in the last decade, begetting concerns regarding its potential health hazards. Drosophila melanogaster four days-old adult female flies were exposed for 30 min to radiation emitted by a commercial mobile phone at a SAR of 0.15 W/kg and a SAE of 270 J/kg. ROS levels and apoptotic follicles were assayed in parallel with a genome-wide microarrays analysis. ROS cellular contents were found to increase by 1.6-fold (x), immediately after the end of exposure, in follicles of pre-choriogenic stages (germarium - stage 10), while sporadically generated apoptotic follicles (germarium 2b and stages 7–9) presented with an averaged 2x upregulation in their sub-population mass, 4 h after fly's irradiation with mobile device. Microarray analysis revealed 168 genes being differentially expressed, 2 h post-exposure, in response to radiofrequency (RF) electromagnetic field-radiation exposure (≥1.25x, P < 0.05) and associated with multiple and critical biological processes, such as basic metabolism and cellular subroutines related to stress response and apoptotic death. Exposure of adult flies to mobile-phone radiation for 30 min has an immediate impact on ROS production in animal's ovary, which seems to cause a global, systemic and non-targeted transcriptional reprogramming of gene expression, 2 h post-exposure, being finally followed by induction of apoptosis 4 h after the end of exposure. Conclusively, this unique type of pulsed radiation, mainly being derived from daily used mobile phones, seems capable of mobilizing critical cytopathic mechanisms, and altering fundamental genetic programs and networks in D. melanogaster. PMID:27960592

Mobile-phone radiation-induced perturbation of gene-expression profiling, redox equilibrium and sporadic-apoptosis control in the ovary of Drosophila melanogaster.

PubMed

Manta, Areti K; Papadopoulou, Deppie; Polyzos, Alexander P; Fragopoulou, Adamantia F; Skouroliakou, Aikaterini S; Thanos, Dimitris; Stravopodis, Dimitrios J; Margaritis, Lukas H

2017-04-03

The daily use by people of wireless communication devices has increased exponentially in the last decade, begetting concerns regarding its potential health hazards. Drosophila melanogaster four days-old adult female flies were exposed for 30 min to radiation emitted by a commercial mobile phone at a SAR of 0.15 W/kg and a SAE of 270 J/kg. ROS levels and apoptotic follicles were assayed in parallel with a genome-wide microarrays analysis. ROS cellular contents were found to increase by 1.6-fold (x), immediately after the end of exposure, in follicles of pre-choriogenic stages (germarium - stage 10), while sporadically generated apoptotic follicles (germarium 2b and stages 7-9) presented with an averaged 2x upregulation in their sub-population mass, 4 h after fly's irradiation with mobile device. Microarray analysis revealed 168 genes being differentially expressed, 2 h post-exposure, in response to radiofrequency (RF) electromagnetic field-radiation exposure (≥1.25x, P < 0.05) and associated with multiple and critical biological processes, such as basic metabolism and cellular subroutines related to stress response and apoptotic death. Exposure of adult flies to mobile-phone radiation for 30 min has an immediate impact on ROS production in animal's ovary, which seems to cause a global, systemic and non-targeted transcriptional reprogramming of gene expression, 2 h post-exposure, being finally followed by induction of apoptosis 4 h after the end of exposure. Conclusively, this unique type of pulsed radiation, mainly being derived from daily used mobile phones, seems capable of mobilizing critical cytopathic mechanisms, and altering fundamental genetic programs and networks in D. melanogaster.

Surface roughness control by extreme ultraviolet (EUV) radiation

NASA Astrophysics Data System (ADS)

Ahad, Inam Ul; Obeidi, Muhannad Ahmed; Budner, Bogusław; Bartnik, Andrzej; Fiedorowicz, Henryk; Brabazon, Dermot

2017-10-01

Surface roughness control of polymeric materials is often desirable in various biomedical engineering applications related to biocompatibility control, separation science and surface wettability control. In this study, Polyethylene terephthalate (PET) polymer films were irradiated with Extreme ultraviolet (EUV) photons in nitrogen environment and investigations were performed on surface roughness modification via EUV exposure. The samples were irradiated at 3 mm and 4 mm distance from the focal spot to investigate the effect of EUV fluence on topography. The topography of the EUV treated PET samples were studied by AFM. The detailed scanning was also performed on the sample irradiated at 3 mm. It was observed that the average surface roughness of PET samples was increased from 9 nm (pristine sample) to 280 nm and 253 nm for EUV irradiated samples. Detailed AFM studies confirmed the presence of 1.8 mm wide period U-shaped channels in EUV exposed PET samples. The walls of the channels were having FWHM of about 0.4 mm. The channels were created due to translatory movements of the sample in horizontal and transverse directions during the EUV exposure. The increased surface roughness is useful for many applications. The nanoscale channels fabricated by EUV exposure could be interesting for microfluidic applications based on lab-on-a-chip (LOC) devices.

Digital Mammography with a Mosaic of CCD-Arrays

NASA Technical Reports Server (NTRS)

Jalink, Antony, Jr. (Inventor); McAdoo, James A. (Inventor)

1996-01-01

The present invention relates generally to a mammography device and method and more particularly to a novel digital mammography device and method to detect microcalcifications of precancerous tissue. A digital mammography device uses a mosaic of electronic digital imaging arrays to scan an x-ray image. The mosaic of arrays is repositioned several times to expose different portions of the image, until the entire image is scanned. The data generated by the arrays during each exposure is stored in a computer. After the final exposure, the computer combines data of the several partial images to produce a composite of the original x-ray image. An aperture plate is used to reduce scatter and the overall exposure of the patient to x-rays. The novelty of this invention is that it provides a digital mammography device with large field coverage, high spatial resolution, scatter rejection, excellent contrast characteristics and lesion detectability under clinical conditions. This device also shields the patient from excessive radiation, can detect extremely small calcifications and allows manipulation and storage of the image.

Occupational exposure to electromagnetic fields from medical sources

PubMed Central

STAM, Rianne; YAMAGUCHI-SEKINO, Sachiko

2017-01-01

High exposures to electromagnetic fields (EMF) can occur near certain medical devices in the hospital environment. A systematic assessment of medical occupational EMF exposure could help to clarify where more attention to occupational safety may be needed. This paper seeks to identify sources of high exposure for hospital workers and compare the published exposure data to occupational limits in the European Union. A systematic search for peer-reviewed publications was conducted via PubMed and Scopus databases. Relevant grey literature was collected via a web search. For each publication, the highest measured magnetic flux density or internal electric field strength per device and main frequency component was extracted. For low frequency fields, high action levels may be exceeded for magnetic stimulation, MRI gradient fields and movement in MRI static fields. For radiofrequency fields, the action levels may be exceeded near devices for diathermy, electrosurgery and hyperthermia and in the radiofrequency field inside MRI scanners. The exposure limit values for internal electric field may be exceeded for MRI and magnetic stimulation. For MRI and magnetic stimulation, practical measures can limit worker exposure. For diathermy, electrosurgery and hyperthermia, additional calculations are necessary to determine if SAR limits may be exceeded in some scenarios. PMID:29109357

Effect of Short-term 900 MHz low level electromagnetic radiation exposure on blood serotonin and glutamate levels.

PubMed

Eris, A H; Kiziltan, H S; Meral, I; Genc, H; Trabzon, M; Seyithanoglu, H; Yagci, B; Uysal, O

2015-01-01

Long term exposure to low level electromagnetic radiation (LLER) by using cellular phones causes serious health problems. Ten male Wistar Albino rats were anesthetized 30 min before the LLER exposure, 0.5 ml blood was taken from the tail vein of rats in order to determine control values. Rats were grouped by three and placed on a plexi-glass flat. A fixed equivalent frequency emitter device was used. A sign to be an electromagnetic field 15.14 V/m (608 mW/m(2)) in strength in the head region with 100 kHz FM modulation at 900 MHz was applied to the animals. After calculating the ideal position for the device, electromagnetic LLER energy was applied for 45 minutes from a distance to be equal with energy transmitted by a mobile phone from a 0.5-1 cm distance to their head regions. After 1.5 hours and before the rats awoke, 0.5 ml of blood was taken from the tail veins in order to determine the treatment values. Plasma 5-HT and glutamate levels were measured by enzyme immunoassay (EIA) using commercial kits. It was found that a single 45 min of LLER exposure increased the blood 5-HT level significantly, but did not change the glutamate level of rats. It was concluded that even a single 45 min of LLER exposure may produce an increase in 5-HT level without changing the blood glutamate level. Increased 5-HT level may lead to a retarded learning and a deficit in spatial memory (Tab. 2, Fig. 2, Ref. 24).

Overview and comparison of lipid-containing semipermeable membrane devices and oysters (Crassostrea gigas) for assessing organic chemical exposure

USGS Publications Warehouse

Huckins, J.N.; Prest, H.F.; Petty, J.D.; Lebo, J.A.; Hodgins, M.M.; Clark, R.C.; Alvarez, D.A.; Gala, W.R.; Steen, A.; Gale, R.; Ingersoll, C.G.

2004-01-01

We performed 20-d, flow-through exposures of lipid-containing semipermeable membrane devices (SPMDs) and Pacific oysters (Crassostrea gigas) to three concentrations (nominally 10, 100, and 250 ng/L) of a diverse mixture of polycyclic aromatic hydrocarbons (PAHs). Exposure water was seawater free of particulates larger than 0.1 μm. The results of these controlled laboratory studies demonstrated that SPMDs and oysters concentrate the same chemicals but that the relative amounts accumulated are different. For oysters, the 20-d mean (across treatments) concentration factors (CFs) of test compounds with log Kow ≤ 4.8 were much lower (4.0- to 20-fold lower) than those of the same compounds in SPMDs. In contrast, the 20-d CFs of PAHs with log Kow ≥ 5.6 in oysters from the low-level treatment were higher than the corresponding CFs for SPMDs. The CFs of these compounds in oysters from the low-level treatment ranged from approximately 3.0- to 13-fold higher than those in oysters from the high-level treatment. This physiologically mediated difference in oyster CFs appears to be linked to active feeding in the low-level treatment and to apparent toxicity-induced cessation of feeding (i.e., valve closure) in the high-level treatment. Because CFs for these compounds in oysters were not independent of exposure concentrations, it follows that tissue levels were not proportional to exposure concentration. However, both sampling approaches have advantages and disadvantages, and the appropriateness of their use depends on the goals of a given study.

Non-Exposure, Device-Assisted Endoscopic Full-thickness Resection.

PubMed

Bauder, Markus; Schmidt, Arthur; Caca, Karel

2016-04-01

Recent developments have expanded the frontier of interventional endoscopy toward more extended resections following surgical principles. This article presents two new device-assisted techniques for endoscopic full-thickness resection in the upper and lower gastrointestinal tract. Both methods are nonexposure techniques avoiding exposure of gastrointestinal contents to the peritoneal cavity by a "close first-cut later" principle. The full-thickness resection device is a novel over-the-scope device designed for clip-assisted full-thickness resection of colorectal lesions. Endoscopic full-thickness resection of gastric subepithelial tumors can be performed after placing transmural sutures underneath the tumor with a suturing device originally designed for endoscopic antireflux therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

An investigation of automatic exposure control calibration for chest imaging with a computed radiography system.

PubMed

Moore, C S; Wood, T J; Avery, G; Balcam, S; Needler, L; Beavis, A W; Saunderson, J R

2014-05-07

The purpose of this study was to examine the use of three physical image quality metrics in the calibration of an automatic exposure control (AEC) device for chest radiography with a computed radiography (CR) imaging system. The metrics assessed were signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQm), all measured using a uniform chest phantom. Subsequent calibration curves were derived to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated chest images with correct detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated chest images contained clinically realistic projected anatomy and anatomical noise and were scored by experienced image evaluators. Constant DDI and CNR curves do not appear to provide optimized performance across the diagnostic energy range. Conversely, constant eNEQm and SNR do appear to provide optimized performance, with the latter being the preferred calibration metric given as it is easier to measure in practice. Medical physicists may use the SNR image quality metric described here when setting up and optimizing AEC devices for chest radiography CR systems with a degree of confidence that resulting clinical image quality will be adequate for the required clinical task. However, this must be done with close cooperation of expert image evaluators, to ensure appropriate levels of detector air kerma.

An investigation of automatic exposure control calibration for chest imaging with a computed radiography system

NASA Astrophysics Data System (ADS)

Moore, C. S.; Wood, T. J.; Avery, G.; Balcam, S.; Needler, L.; Beavis, A. W.; Saunderson, J. R.

2014-05-01

The purpose of this study was to examine the use of three physical image quality metrics in the calibration of an automatic exposure control (AEC) device for chest radiography with a computed radiography (CR) imaging system. The metrics assessed were signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQm), all measured using a uniform chest phantom. Subsequent calibration curves were derived to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated chest images with correct detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated chest images contained clinically realistic projected anatomy and anatomical noise and were scored by experienced image evaluators. Constant DDI and CNR curves do not appear to provide optimized performance across the diagnostic energy range. Conversely, constant eNEQm and SNR do appear to provide optimized performance, with the latter being the preferred calibration metric given as it is easier to measure in practice. Medical physicists may use the SNR image quality metric described here when setting up and optimizing AEC devices for chest radiography CR systems with a degree of confidence that resulting clinical image quality will be adequate for the required clinical task. However, this must be done with close cooperation of expert image evaluators, to ensure appropriate levels of detector air kerma.

Musculoskeletal impact of the use of various types of electronic devices on university students in Hong Kong: An evaluation by means of self-reported questionnaire.

PubMed

Woo, Eugenia H C; White, Peter; Lai, Christopher W K

2016-12-01

Despite the increasingly widespread popularity of electronic devices, there are limited comprehensive studies on the effects of usage and exposure to multiple electronic devices over extended periods of time. Therefore, this study explored the cumulative musculoskeletal implications of exposure to various electronic devices among university students. A self-reported questionnaire was administered in the university in Hong Kong and students provided information about the frequency and duration of electronic devices use, including computers, mobile phones and game consoles, and reported on any musculoskeletal pain or discomfort that may relate to electronic devices usage in the immediate 12 months prior to the survey date. A total of 503 university students (59% males and 41% females) aged 18-25 years completed the questionnaire. The results showed that 251 (49.9%) respondents reported upper limb musculoskeletal symptoms, particularly in the neck and shoulder regions. Among these, 155 (61.8%) indicated that their discomfort was related to electronic device usage. Statistically significant differences in exposure to electronic devices and musculoskeletal outcomes between genders were found (p < 0.05). The use of electronic devices and habitual postures were associated with musculoskeletal problems among university students in Hong Kong. This phenomenon highlights the urgent need for ergonomics education and recommendations to increase students' awareness of musculoskeletal wellbeing. Copyright © 2016 Elsevier Ltd. All rights reserved.

NOTE: A method for controlling image acquisition in electronic portal imaging devices

NASA Astrophysics Data System (ADS)

Glendinning, A. G.; Hunt, S. G.; Bonnett, D. E.

2001-02-01

Certain types of camera-based electronic portal imaging devices (EPIDs) which initiate image acquisition based on sensing a change in video level have been observed to trigger unreliably at the beginning of dynamic multileaf collimation sequences. A simple, novel means of controlling image acquisition with an Elekta linear accelerator (Elekta Oncology Systems, Crawley, UK) is proposed which is based on illumination of a photodetector (ORP-12, Silonex Inc., Plattsburgh, NY, USA) by the electron gun of the accelerator. By incorporating a simple trigger circuit it is possible to derive a beam on/off status signal which changes at least 100 ms before any dose is measured by the accelerator. The status signal does not return to the beam-off state until all dose has been delivered and is suitable for accelerator pulse repetition frequencies of 50-400 Hz. The status signal is thus a reliable means of indicating the initiation and termination of radiation exposure, and thus controlling image acquisition of such EPIDs for this application.

Comparison of average global exposure of population induced by a macro 3G network in different geographical areas in France and Serbia.

PubMed

Huang, Yuanyuan; Varsier, Nadège; Niksic, Stevan; Kocan, Enis; Pejanovic-Djurisic, Milica; Popovic, Milica; Koprivica, Mladen; Neskovic, Aleksandar; Milinkovic, Jelena; Gati, Azeddine; Person, Christian; Wiart, Joe

2016-09-01

This article is the first thorough study of average population exposure to third generation network (3G)-induced electromagnetic fields (EMFs), from both uplink and downlink radio emissions in different countries, geographical areas, and for different wireless device usages. Indeed, previous publications in the framework of exposure to EMFs generally focused on individual exposure coming from either personal devices or base stations. Results, derived from device usage statistics collected in France and Serbia, show a strong heterogeneity of exposure, both in time, that is, the traffic distribution over 24 h was found highly variable, and space, that is, the exposure to 3G networks in France was found to be roughly two times higher than in Serbia. Such heterogeneity is further explained based on real data and network architecture. Among those results, authors show that, contrary to popular belief, exposure to 3G EMFs is dominated by uplink radio emissions, resulting from voice and data traffic, and average population EMF exposure differs from one geographical area to another, as well as from one country to another, due to the different cellular network architectures and variability of mobile usage. Bioelectromagnetics. 37:382-390, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Photodynamic antimicrobial chemotherapy on Streptococcus mutans using curcumin and toluidine blue activated by a novel LED device.

PubMed

Paschoal, Marco Aurelio; Lin, Meng; Santos-Pinto, Lourdes; Duarte, Simone

2015-02-01

Photodynamic antimicrobial chemotherapy (PACT) is an antimicrobial approach that uses photosensitizers (PS) in combination with light sources at specific wavelengths aiming the production of reactive oxygen species. The long illumination time necessary to active PS is a challenge in PACT. Thus, this study investigated the antimicrobial effect of a novel single source of light-emitting diode (LED) light that covers the entire spectrum of visible light beyond interchangeable probes at high power intensity. Blue and red LED probes were used into different exposure times to active different concentrations of curcumin (C) and toluidine blue (T) on planktonic suspensions of Streptococcus mutans UA 159 (S. mutans). S. mutans were standardized and submitted to (1) PACT treatment at three concentrations of C and T exposure at three radiant exposures of a blue LED (BL) (C+BL+) and a red LED (RL) (T+RL+), (2) C (C+BL-) or T alone (T+RL-), (3) both LED lights (C-BL+ and T-RL+), and (4) neither PS nor LED illumination (control group: C-BL- and T-RL-). Aliquots of the suspensions were diluted and cultured on blood agar plates. The number of colony-forming units was calculated after 48 h. The groups submitted to PACT presented a lethal photokilling rate to all PS concentrations at tested dosimetries. The comparison to control group when PS and LED lights used alone demonstrated no decrease in the number of viable bacterial counts. The novel LED device in combination with curcumin and toluidine blue promoted an effective photoinactivation of S. mutans suspensions at ultrashort light illumination times.

Exposure and Use of Mobile Media Devices by Young Children.

PubMed

Kabali, Hilda K; Irigoyen, Matilde M; Nunez-Davis, Rosemary; Budacki, Jennifer G; Mohanty, Sweta H; Leister, Kristin P; Bonner, Robert L

2015-12-01

Research on children's use of mobile media devices lags behind its adoption. The objective of this study was to examine young children's exposure to and use of mobile media devices. Cross-sectional study of 350 children aged 6 months to 4 years seen October to November 2014 at a pediatric clinic in an urban, low-income, minority community. The survey was adapted from Common Sense Media's 2013 nationwide survey. Most households had television (97%), tablets (83%), and smartphones (77%). At age 4, half the children had their own television and three-fourths their own mobile device. Almost all children (96.6%) used mobile devices, and most started using before age 1. Parents gave children devices when doing house chores (70%), to keep them calm (65%), and at bedtime (29%). At age 2, most children used a device daily and spent comparable screen time on television and mobile devices. Most 3- and 4-year-olds used devices without help, and one-third engaged in media multitasking. Content delivery applications such as YouTube and Netflix were popular. Child ownership of device, age at first use, and daily use were not associated with ethnicity or parent education. Young children in an urban, low-income, minority community had almost universal exposure to mobile devices, and most had their own device by age 4. The patterns of use suggest early adoption, frequent and independent use, and media multitasking. Studies are urgently needed to update recommendations for families and providers on the use of mobile media by young children. Copyright © 2015 by the American Academy of Pediatrics.

[Comparative studies of personal and steady-state sampling for determining dust exposure in different job groups].

PubMed

Cherneva, P; Lukanova, R

1994-01-01

The variability of the dust concentration in time and space, as well as the change of worker's place during the working process, define the necessity of introducing personal sampling in the hygiene control practice. However, the laboratory equipment with personal devices is still not sufficient. The aim of this work is to assess the dust exposure of the basic professional groups from the ore- and coal production in Bulgaria by personal sampling in comparative studies of the static ambient sampling used up to now. 63 full-shift investigations of the dust factor were performed on professional groups of miners of the polymetal and coal pits by static ambient devices-[Hygitest production] and personal [from firms "Casella", "Strolein" and "Gilian"] devices, after standardized methods. The results are data processed-by means of logarithmic normal distribution of the relation of the respirable dust concentrations, determined personally and by static ambient sampling. The limits of variation of this correlation are from 0.5 to 4.1 at average geometric value -0.95 and standard geometric deviation-1.8 i.e. both types of sampling are intersubstitutional for the examined groups and sites, as in the underground ores the professional risk of respirable dust is underestimated up to 4 times at static ambient sampling.

Apparatus for unloading pressurized fluid

DOEpatents

Rehberger, Kevin M.

1994-01-01

An apparatus for unloading fluid, preferably pressurized gas, from containers in a controlled manner that protects the immediate area from exposure to the container contents. The device consists of an unloading housing, which is enclosed within at least one protective structure, for receiving the dispensed contents of the steel container, and a laser light source, located external to the protective structure, for opening the steel container instantaneously. The neck or stem of the fluid container is placed within the sealed interior environment of the unloading housing. The laser light passes through both the protective structure and the unloading housing to instantaneously pierce a small hole within the stem of the container. Both the protective structure and the unloading housing are specially designed to allow laser light passage without compromising the light's energy level. Also, the unloading housing allows controlled flow of the gas once it has been dispensed from the container. The external light source permits remote operation of the unloading device.

Implementing bright light treatment for MSFC payload operations shiftworkers

NASA Technical Reports Server (NTRS)

Hayes, Benita C.; Stewart, Karen T.; Eastman, Charmane I.

1994-01-01

Intense light can phase-shift circadian rhythms and improve performance, sleep, and wellbeing during shiftwork simulations, but to date there have been very few attempts to administer light treatment to real shiftworkers. We have developed procedures for implementing light treatment and have conducted controlled trials of light treatment for MSFC Payload Operations staff during the USML-1 mission. We found that treatment had beneficial effects on fatigue, alertness, self-rated job performance, sleep, mood, and work attendance. Although there are portable bright light boxes commercially available, there is no testing protocol and little performance information available. We measure the illuminance of two candidate boxes for use in this study and found that levels were consistently lower than those advertised by manufacturers. A device was developed to enhance the illuminance output of such units. This device increased the illuminance by at least 60 % and provided additional improvements in visual comfort and overall exposure. Both the design of this device and some suggested procedures for evaluating light devices are presented.

Cost-effective rapid prototyping and assembly of poly(methyl methacrylate) microfluidic devices.

PubMed

Matellan, Carlos; Del Río Hernández, Armando E

2018-05-03

The difficulty in translating conventional microfluidics from laboratory prototypes to commercial products has shifted research efforts towards thermoplastic materials for their higher translational potential and amenability to industrial manufacturing. Here, we present an accessible method to fabricate and assemble polymethyl methacrylate (PMMA) microfluidic devices in a "mask-less" and cost-effective manner that can be applied to manufacture a wide range of designs due to its versatility. Laser micromachining offers high flexibility in channel dimensions and morphology by controlling the laser properties, while our two-step surface treatment based on exposure to acetone vapour and low-temperature annealing enables improvement of the surface quality without deformation of the device. Finally, we demonstrate a capillarity-driven adhesive delivery bonding method that can produce an effective seal between PMMA devices and a variety of substrates, including glass, silicon and LiNbO 3 . We illustrate the potential of this technique with two microfluidic devices, an H-filter and a droplet generator. The technique proposed here offers a low entry barrier for the rapid prototyping of thermoplastic microfluidics, enabling iterative design for laboratories without access to conventional microfabrication equipment.

A Summary of Research and Progress on Carbon Monoxide Exposure Control Solutions on Houseboats

PubMed Central

Hall, Ronald M.; Earnest, G. Scott; Hammond, Duane R.; Dunn, Kevin H.; Garcia, Alberto

2015-01-01

Investigations of carbon monoxide (CO-related poisonings and deaths on houseboats were conducted by the Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health. These investigations measured hazardous CO concentrations on and around houseboats that utilize gasoline-powered generators. Engineering control devices were developed and tested to mitigate this deadly hazard. CO emissions were measured using various sampling techniques which included exhaust emission analyzers, detector tubes, evacuated containers (grab air samples analyzed by a gas chromatograph), and direct-reading CO monitors. CO results on houseboats equipped with gasoline-powered generators without emission controls indicated hazardous CO concentrations exceeding immediately dangerous to life and health (IDLH) levels in potentially occupied areas of the houseboat. Air sample results on houseboats that were equipped with engineering controls to remove the hazard were highly effective and reduced CO levels by over 98% in potentially occupied areas. The engineering control devices used to reduce the hazardous CO emissions from gasoline-powered generators on houseboats were extremely effective at reducing CO concentrations to safe levels in potentially occupied areas on the houseboats and are now beginning to be widely used. PMID:24568306

A summary of research and progress on carbon monoxide exposure control solutions on houseboats.

PubMed

Hall, Ronald M; Earnest, G Scott; Hammond, Duane R; Dunn, Kevin H; Garcia, Alberto

2014-01-01

Investigations of carbon monoxide (CO-related poisonings and deaths on houseboats were conducted by the Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health. These investigations measured hazardous CO concentrations on and around houseboats that utilize gasoline-powered generators. Engineering control devices were developed and tested to mitigate this deadly hazard. CO emissions were measured using various sampling techniques which included exhaust emission analyzers, detector tubes, evacuated containers (grab air samples analyzed by a gas chromatograph), and direct-reading CO monitors. CO results on houseboats equipped with gasoline-powered generators without emission controls indicated hazardous CO concentrations exceeding immediately dangerous to life and health (IDLH) levels in potentially occupied areas of the houseboat. Air sample results on houseboats that were equipped with engineering controls to remove the hazard were highly effective and reduced CO levels by over 98% in potentially occupied areas. The engineering control devices used to reduce the hazardous CO emissions from gasoline-powered generators on houseboats were extremely effective at reducing CO concentrations to safe levels in potentially occupied areas on the houseboats and are now beginning to be widely used.

An in vitro method for detecting chemical sensitization using human reconstructed skin models and its applicability to cosmetic, pharmaceutical, and medical device safety testing.

PubMed

McKim, James M; Keller, Donald J; Gorski, Joel R

2012-12-01

Chemical sensitization is a serious condition caused by small reactive molecules and is characterized by a delayed type hypersensitivity known as allergic contact dermatitis (ACD). Contact with these molecules via dermal exposure represent a significant concern for chemical manufacturers. Recent legislation in the EU has created the need to develop non-animal alternative methods for many routine safety studies including sensitization. Although most of the alternative research has focused on pure chemicals that possess reasonable solubility properties, it is important for any successful in vitro method to have the ability to test compounds with low aqueous solubility. This is especially true for the medical device industry where device extracts must be prepared in both polar and non-polar vehicles in order to evaluate chemical sensitization. The aim of this research was to demonstrate the functionality and applicability of the human reconstituted skin models (MatTek Epiderm(®) and SkinEthic RHE) as a test system for the evaluation of chemical sensitization and its potential use for medical device testing. In addition, the development of the human 3D skin model should allow the in vitro sensitization assay to be used for finished product testing in the personal care, cosmetics, and pharmaceutical industries. This approach combines solubility, chemical reactivity, cytotoxicity, and activation of the Nrf2/ARE expression pathway to identify and categorize chemical sensitizers. Known chemical sensitizers representing extreme/strong-, moderate-, weak-, and non-sensitizing potency categories were first evaluated in the skin models at six exposure concentrations ranging from 0.1 to 2500 µM for 24 h. The expression of eight Nrf2/ARE, one AhR/XRE and two Nrf1/MRE controlled gene were measured by qRT-PCR. The fold-induction at each exposure concentration was combined with reactivity and cytotoxicity data to determine the sensitization potential. The results demonstrated that both the MatTek and SkinEthic models performed in a manner consistent with data previously reported with the human keratinocyte (HaCaT) cell line. The system was tested further by evaluating chemicals known to be associated with the manufacture of medical devices. In all cases, the human skin models performed as well or better than the HaCaT cell model previously evaluated. In addition, this study identifies a clear unifying trigger that controls both the Nrf2/ARE pathway and essential biochemical events required for the development of ACD. Finally, this study has demonstrated that by utilizing human reconstructed skin models, it is possible to evaluate non-polar extracts from medical devices and low solubility finished products.

Knowledge, Attitudes, Practices and Biomonitoring of Farmers and Residents Exposed to Pesticides in Brazil

PubMed Central

Oliveira Pasiani, Juliana; Torres, Priscila; Roniery Silva, Juciê; Zago Diniz, Bruno; Dutra Caldas, Eloisa

2012-01-01

In this study, the knowledge, attitudes and practices regarding pesticide use and the levels of exposure of farmers and residents to organophosphorous and/or carbamates pesticides were evaluated in two rural settings in Brazil. A questionnaire was completed by 112 farm workers aged ≥18 years. Almost all farmers acknowledged that pesticides were potentially harmful to their health (87.5%); however, over half rarely (48.2%) or never (7.2%) used personal protective devices (PPDs). An association was found (p = 0.001) between the work regimen and the use of PPDs, with more frequent equipment use among hired laborers than those involved in family agriculture. A significant correlation (p = 0.027) was found between the reporting of adverse symptoms and the use of backpack sprayers. Mean AChE activities of farmers (n = 64) and residents (n = 18) during the exposure and non-exposure periods were significantly lower than their control groups. Mean BChE activities of farmers and residents were significantly lower than their controls during the exposure period. Among the 60 farmers that had blood samples collected in both the exposure and non-exposure (baseline) periods, 10 (16.7%) had AChE depletion of over 30% during the exposure period compared with the baseline level. Six residents living on the same farms also presented this depletion. AChE was over 30% higher than the baseline level for 19 farmers (31.7%), indicating a reboot effect. Special education programs are needed in these regions to promote the safe use of pesticides in the field to decrease the risks from exposure to pesticides for farmers, and from secondary exposure to these compounds for their families. PMID:23202670

Personal radiofrequency electromagnetic field exposure measurements in Swiss adolescents.

PubMed

Roser, Katharina; Schoeni, Anna; Struchen, Benjamin; Zahner, Marco; Eeftens, Marloes; Fröhlich, Jürg; Röösli, Martin

2017-02-01

Adolescents belong to the heaviest users of wireless communication devices, but little is known about their personal exposure to radiofrequency electromagnetic fields (RF-EMF). The aim of this paper is to describe personal RF-EMF exposure of Swiss adolescents and evaluate exposure relevant factors. Furthermore, personal measurements were used to estimate average contributions of various sources to the total absorbed RF-EMF dose of the brain and the whole body. Personal exposure was measured using a portable RF-EMF measurement device (ExpoM-RF) measuring 13 frequency bands ranging from 470 to 3600MHz. The participants carried the device for three consecutive days and kept a time-activity diary. In total, 90 adolescents aged 13 to 17years participated in the study conducted between May 2013 and April 2014. In addition, personal measurement values were combined with dose calculations for the use of wireless communication devices to quantify the contribution of various RF-EMF sources to the daily RF-EMF dose of adolescents. Main contributors to the total personal RF-EMF measurements of 63.2μW/m 2 (0.15V/m) were exposures from mobile phones (67.2%) and from mobile phone base stations (19.8%). WLAN at school and at home had little impact on the personal measurements (WLAN accounted for 3.5% of total personal measurements). According to the dose calculations, exposure from environmental sources (broadcast transmitters, mobile phone base stations, cordless phone base stations, WLAN access points, and mobile phones in the surroundings) contributed on average 6.0% to the brain dose and 9.0% to the whole-body dose. RF-EMF exposure of adolescents is dominated by their own mobile phone use. Environmental sources such as mobile phone base stations play a minor role. Copyright © 2016 Elsevier Ltd. All rights reserved.

Complying with the Occupational Safety and Health Administration's Bloodborne Pathogens Standard: implementing needleless systems and intravenous safety devices.

PubMed

Marini, Michelle A; Giangregorio, Maeve; Kraskinski, Joanna C

2004-03-01

Preventing the transmission of bloodborne pathogens to healthcare workers has been a mission and a challenge of the healthcare industry for over 20 years. The development of the Occupational Safety and Health Administration Bloodborne Pathogens Standard in 1991 and the passing of the Needlestick Safety Act in 2000 mandated hospitals to develop an Exposure Control Plan to protect workers from these pathogens. Children's Hospital Boston began implementation of a needleless system in 1993. Employees readily accepted these systems into practice, because they were convenient and easy to use. A marked decrease in exposures to bloodborne pathogens naturally followed, which is consistent with the national data. The transition to intravenous (i.v.) safety devices at Children's Hospital began in 2000 and proved to be more of a challenge. First, the clinicians must choose a safety product, which requires developing and implementing a trial plan with potential catheters. This selection process is especially difficult in pediatrics where successful placement of the smallest-gauge catheter, no. 24, is imperative. After choosing an i.v. safety product, successful transition is dependent upon the thoroughness of i.v. safety device training and a commitment by the clinicians to the use of these products. Although the number of needlestick injuries and subsequent transmission of bloodborne pathogens have been further reduced with the use of i.v. safety devices, needlestick injuries still occur. This results from a lack of familiarity with the engineering of the device and therefore poor technique or a failure to activate the safety mechanism. Staff resistance due to loss of expertise with the new device and patient care concerns are additional barriers to the use of these new products. Addressing these obstacles and providing adequate training for all clinicians were required for successful implementation of these i.v. safety devices.

Effect of Pile-Driving Sounds on the Survival of Larval Fish.

PubMed

Bolle, Loes J; de Jong, Christ A F; Bierman, Stijn M; van Beek, Pieter J G; Wessels, Peter W; Blom, Ewout; van Damme, Cindy J G; Winter, Hendrik V; Dekeling, René P A

2016-01-01

Concern exists about the potential effects of pile-driving sounds on fish, but evidence is limited, especially for fish larvae. A device was developed to expose larvae to accurately reproduced pile-driving sounds. Controlled exposure experiments were carried out to examine the lethal effects in common sole larvae. No significant effects were observed at zero-to-peak pressure levels up to 210 dB re 1 μPa(2) and cumulative sound exposure levels up to 206 dB re 1 μPa(2)·s, which is well above the US interim criteria for nonauditory tissue damage in fish. Experiments are presently being carried out for European sea bass and herring larvae.

Phase holograms in polymethyl methacrylate

NASA Technical Reports Server (NTRS)

Maker, P. D.; Muller, R. E.

1992-01-01

A procedure is described for the fabrication of complex computer-generated phase holograms in polymethyl methacrylate (PMMA) by means of partial-exposure e-beam lithography and subsequent carefully controlled partial development. Following the development, the pattern appears (rendered in relief) in the PMMA, which then acts as the phase-delay medium. The devices fabricated were designed with 16 equal phase steps per retardation cycle, were up to 3 mm square, and consisted of up to 10 millions of 0.3-2.0-micron square pixels. Data files were up to 60 Mb-long, and the exposure times ranged to several hours. A Fresnel phase lens was fabricated with a diffraction-limited optical performance of 83-percent efficiency.

METHODS STUDIES FOR THE NATIONAL CHILDREN'S STUDY: SEMIPERMEABLE MEMBRANE DEVICE (SPMD)

EPA Science Inventory

Accurate exposure classification tools are required to link exposure with health effects in epidemiological studies. Although long-term integrated exposure measurements are a critical component of exposure assessment, the ability to include these measurements into epidemiologic...

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

PubMed

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 < .05) in the levels of germinal epithelial diameter in all the experimental groups compared with the control group. There was no significant change (p < .05) in cross-sectional diameter of all the experimental groups compared with the control group. Group D rats showed a significant decrease (p ˂ .05) in lumen diameter compared with group B rats. There was an uneven distribution of germinal epithelial cells in groups B, C and D. However, there was degeneration of the epithelia cells in group D when compared to the control and group B rats. Sera levels of malondialdehyde (MDA) and superoxide dismutase (SOD), which are markers of reactive oxygen species, significantly increased (MDA) and decreased (SOD), respectively, in all the experimental groups compared with the control group. Also sera levels of gonadotropic hormones (FSH, LH and testosterone) significantly decreased (p < .05) in groups C and D compared with the control group. The study demonstrates that chronic exposure to radiofrequency 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.

Eye protection in dental laboratories.

PubMed

Palenik, C J

1997-09-01

Many dental laboratory procedures increase the chances of serious eye injury. This would include traumatic injuries due to projectiles or through exposure to harsh chemicals or heat and infections from contact with patient body fluids. To help assure a safer working environment, awareness of the need for eye protection must be established and maintained by all laboratory personnel. The purpose of this article are: 1) to list the applicable federal regulations concerning eye safety in dental laboratory workplaces; 2) to describe the various types of appropriate eyewear; and 3) to identify which protective devices best prevent exposure to specific types of hazards. The goal of this article is to help dental laboratories with their employee safety programs, especially concerning the selection of protective eyewear. Such programs must include engineering controls and work practice controls plus appropriate personal protective equipment. Laboratories today must comply with safety mandates in the most effective and efficient manner.

Enabling optical metrology on small 5×5μm2 in-cell targets to support flexible sampling and higher order overlay and CD control for advanced logic devices nodes

NASA Astrophysics Data System (ADS)

Salerno, Antonio; de la Fuente, Isabel; Hsu, Zack; Tai, Alan; Chang, Hammer; McNamara, Elliott; Cramer, Hugo; Li, Daoping

2018-03-01

In next generation Logic devices, overlay control requirements shrink to sub 2.5nm level on-product overlay. Historically on-product overlay has been defined by the overlay capability of after-develop in-scribe targets. However, due to design and dimension, the after development metrology targets are not completely representative for the final overlay of the device. In addition, they are confined to the scribe-lane area, which limits the sampling possibilities. To address these two issues, metrology on structures matching the device structure and which can be sampled with high density across the device is required. Conventional after-etch CDSEM techniques on logic devices present difficulties in discerning the layers of interest, potential destructive charging effects and finally, they are limited by the long measurement times[1] [2] [3] . All together, limit the sampling densities and making CDSEM less attractive for control applications. Optical metrology can overcome most of these limitations. Such measurement, however, does require repetitive structures. This requirement is not fulfilled by logic devices, as the features vary in pitch and CD over the exposure field. The solution is to use small targets, with a maximum pad size of 5x5um2 , which can easily be placed in the logic cell area. These targets share the process and architecture of the device features of interest, but with a modified design that replicates as close as possible the device layout, allowing for in-device metrology for both CD and Overlay. This solution enables measuring closer to the actual product feature location and, not being limited to scribe-lanes, it opens the possibility of higher-density sampling schemes across the field. In summary, these targets become the facilitator of in-device metrology (IDM), that is, enabling the measurements both in-device Overlay and the CD parameters of interest and can deliver accurate, high-throughput, dense and after-etch measurements for Logic. Overlay improvements derived from a high-densely sampled Overlay map measured with 5x5 um2 In Device Metrology (IDM) targets were investigated on a customer Logic application. In this work we present both the main design aspects of the 5x5 um2 IDM targets, as well as the results on the improved Overlay performance.

Soft x-ray pinhole imaging diagnostics for compact toroid plasmas

NASA Astrophysics Data System (ADS)

Crawford, E. A.; Taggart, D. P.; Bailey, A. D., III

1990-10-01

Soft x-ray pinhole imaging has recently become established as a valuable diagnostic for visualization of field reversed configuration (FRC) plasmas in the TRX-2, FRX-C/LSM devices. Gated MCP image converter devices with CsI cathodes and Be filters with a peak response around 11 nm wavelength are used for exposure durations ranging from a few tenths up to several microseconds. Results of experiments with single and Chevron channel plates are discussed along with estimates of linear exposure limitations with both film and CCD cameras as recording media. Plans for multiframe devices on the FRX-C/LSM and the LSX devices are also discussed.

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

Code of Federal Regulations, 2011 CFR

2011-10-01

... their effective radiated power (ERP) is 1.5 watts or more, or if they operate at frequencies above 1.5 GHz and their ERP is 3 watts or more. Unlicensed personal communications service devices, unlicensed... exposure prior to equipment authorization or use if their ERP is 3 watts or more or if they meet the...

The high energy multicharged particle exposure of the microbial ecology evaluation device on board the Apollo 16 spacecraft

NASA Technical Reports Server (NTRS)

Benton, E. V.; Henke, R. P.

1973-01-01

The high energy multicharged cosmic-ray-particle exposure of the Microbial Ecology Evaluation Device package on board the Apollo 16 spacecraft was monitored using cellulose nitrate, Lexan polycarbonate, nuclear emulsion, and silver chloride crystal nuclear-track detectors. The results of the analysis of these detectors include the measured particle fluences, the linear energy transfer spectra, and the integral atomic number spectrum of stopping particle density. The linear energy transfer spectrum is used to compute the fractional cell loss in human kidney (T1) cells caused by heavy particles. Because the Microbial Ecology Evaluation Device was better shielded, the high-energy multicharged particle exposure was less than that measured on the crew passive dosimeters.

Ultraviolet spectral distribution and erythema-weighted irradiance from indoor tanning devices compared with solar radiation exposures.

PubMed

Sola, Yolanda; Baeza, David; Gómez, Miguel; Lorente, Jerónimo

2016-08-01

Concern regarding the impact of indoor tanning devices on human health has led to different regulations and recommendations, which set limits on erythema-weighted irradiance. Here, we analyze spectral emissions from 52 tanning devices in Spanish facilities and compare them with surface solar irradiance for different solar zenith angles. Whereas most of the devices emitted less UV-B radiation than the midday summer sun, the unweighted UV-A irradiance was 2-6 times higher than solar radiation. Moreover, the spectral distributions of indoor devices were completely different from that of solar radiation, differing in one order of magnitude at some UV-A wavelengths, depending on the lamp characteristics. In 21% of the devices tested, the erythema-weighted irradiance exceeded 0.3Wm(-2): the limit fixed by the European standard and the Spanish regulation. Moreover, 29% of the devices fall within the UV type 4 classification, for which medical advice is required. The high variability in erythema-weighted irradiance results in a wide range of exposure times to reach 1 standard erythemal dose (SED: 100Jm(-2)), with 62% of devices requiring exposures of <10min to reach 1 SED. Nevertheless, the unweighted UV-A dose during this time period would be from 1.4 to 10.3 times more than the solar UV-A dose. Copyright © 2016 Elsevier B.V. All rights reserved.

A case-control study of eye injuries in the workplace in Hong Kong.

PubMed

Yu, Tak Sun Ignatius; Liu, Hongjie; Hui, Karen

2004-01-01

Eye injury in the workplace is common worldwide. This study proposed to explore both risk and preventive factors re eye injuries in Hong Kong. Case-control study. A total of 239 work-related eye injury patients, and 253 subjects without a history of any eye injury as controls. Patients with all incident cases of work-related eye injuries attending the ophthalmology clinics of 3 major public hospitals in Hong Kong during the first 3 months of 2000 were invited to participate. Controls were selected from the general population and were frequency matched to patients based on gender. Patients were interviewed face-to-face by trained interviewers in the ophthalmology clinics, using a structured questionnaire. Telephone interviews were used for controls. Risk and protective factors associated with eye injuries. Among eye injury cases, 158 patients (66.1%) reported having incurred 1 episode of eye injury during employment, 49 (20.5%) having suffered 2 episodes, and 32 (13.4%) having experienced >/==" BORDER="0">3 eye injuries at work. Most of the patients (85.4%) did not wear any protective devices at the time of injury. Subjects who wore safety glasses regularly were less likely to have eye injuries (odds ratio [OR] = 0.29, 95% confidence interval [CI] = 0.14-0.62). Having a safety requirement for wearing safety glasses was negatively associated with eye injuries (OR = 0.31, 95% CI = 0.15-0.62). Multivariate analysis indicated that exposures to certain work hazards and working in the construction industry were positively associated with eye injuries. Subjects who worked longer in their current job, who reported having received job safety training before employment, or whose machines or equipment were maintained or repaired regularly by employers were at lower risk of experiencing eye injuries. Construction workers and those exposed to multiple hazards may get eye injuries at work. They should be provided with protective devices that are effective in preventing such exposures. Health education and safety training are important in preventing eye injuries. Maintenance and repair of machines and equipment may effectively reduce or eliminate the sources of exposures.

Noise-induced hearing loss in young adults: the role of personal listening devices and other sources of leisure noise.

PubMed

Mostafapour, S P; Lahargoue, K; Gates, G A

1998-12-01

No consensus exists regarding the magnitude of the risk of noise-induced hearing loss (NIHL) associated with leisure noise, in particular, personal listening devices in young adults. Examine the magnitude of hearing loss associated with personal listening devices and other sources of leisure noise in causing NIHL in young adults. Prospective auditory testing of college student volunteers with retrospective history exposure to home stereos, personal listening devices, firearms, and other sources of recreational noise. Subjects underwent audiologic examination consisting of estimation of pure-tone thresholds, speech reception thresholds, and word recognition at 45 dB HL. Fifty subjects aged 18 to 30 years were tested. All hearing thresholds of all subjects (save one-a unilateral 30 dB HL threshold at 6 kHz) were normal, (i.e., 25 dB HL or better). A 10 dB threshold elevation (notch) in either ear at 3 to 6 kHz as compared with neighboring frequencies was noted in 11 (22%) subjects and an unequivocal notch (15 dB or greater) in either ear was noted in 14 (28%) of subjects. The presence or absence of any notch (small or large) did not correlate with any single or cumulative source of noise exposure. No difference in pure-tone threshold, speech reception threshold, or speech discrimination was found among subjects when segregated by noise exposure level. The majority of young users of personal listening devices are at low risk for substantive NIHL. Interpretation of the significance of these findings in relation to noise exposure must be made with caution. NIHL is an additive process and even subtle deficits may contribute to unequivocal hearing loss with continued exposure. The low prevalence of measurable deficits in this study group may not exclude more substantive deficits in other populations with greater exposures. Continued education of young people about the risk to hearing from recreational noise exposure is warranted.

Passive exposure to electronic cigarette (e-cigarette) use increases desire for combustible and e-cigarettes in young adult smokers.

PubMed

King, Andrea C; Smith, Lia J; McNamara, Patrick J; Matthews, Alicia K; Fridberg, Daniel J

2015-09-01

Passive exposure to combustible cigarette use has been shown to act as a cue to increase smoking urge. Given the resemblance of e-cigarettes and other electronic nicotine delivery systems (ENDS) to combustible cigarettes, we examined whether these devices could also act as a cue to increase smoking desire and urges in those passively exposed. Young adult daily smokers (age 18-35 years; N=60) completed subjective ratings before and after exposure to a study confederate drinking bottled water (control cue) and then smoking either a combustible or e-cigarette (active cue). Smoking desire and urge ratings were measured with visual analogue scale items for desire for a regular and an e-cigarette and the Brief Questionnaire of Smoking Urges. Passive exposure to both the e-cigarette and combustible cigarette cue significantly increased observers' ratings of desire and urge to smoke a regular cigarette (all ps<0.05). Exposure to the e-cigarette cue but not the regular cigarette cue also increased desire to smoke an e-cigarette (p<0.01). The results provide the first evidence in a controlled setting that electronic cigarette exposure may evoke smoking urges in young adult daily smokers. With replication, these findings may have relevance for ENDS regulation and policy. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Exposure Levels for Chemical Threat Compounds; Information to Facilitate Chemical Incident Response

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

Hauschild, Veronique; Watson, Annetta Paule

2013-01-01

Exposure Standards, Limits and Guidelines for Chemical Threat Compunds ABSTRACT Exposure criteria for chemical warfare (CW) agents and certain toxic industrial chemicals (TICs) used as CW agents (such as chlorine fill in an improvised explosive device) have been developed for protection of the civilian general public, civilian employees in chemical agent processing facilities and deployed military populations. In addition, compound-specific concentrations have been developed to serve as how clean is clean enough clearance criteria guiding facility recovery following chemical terrorist or other hazardous release events. Such criteria are also useful to verify compound absence, identify containment boundaries and expedite facilitymore » recovery following chemical threat release. There is no single right value or concentration appropriate for all chemical hazard control applications. It is acknowledged that locating and comparing the many sources of CW agent and TIC exposure criteria has not been previously well-defined. This paper summarizes many of these estimates and assembles critical documentation regarding their derivation and use.« less

Exposures of Sus scrofa to a TASER(®) conducted electrical weapon: no effects on 2-dimensional gel electrophoresis patterns of plasma proteins.

PubMed

Jauchem, James R; Cerna, Cesario Z; Lim, Tiffany Y; Seaman, Ronald L

2014-12-01

In an earlier study, we found significant changes in red-blood-cell, leukocyte, and platelet counts, and in red-blood-cell membrane proteins, following exposures of anesthetized pigs to a conducted electrical weapon. In the current study, we examined potential changes in plasma proteins [analyzed via two-dimensional gel electrophoresis (2-DGE)] following two 30 s exposures of anesthetized pigs (Sus scrofa) to a TASER (®) C2 conducted electrical weapon. Patterns of proteins, separated by 2-DGE, were consistent and reproducible between animals and between times of sampling. We determined that the blood plasma collection, handling, storage, and processing techniques we used are suitable for swine blood. There were no statistically significant changes in plasma proteins following the conducted-electrical-weapon exposures. Overall gel patterns of fibrinogen were similar to results of other studies of both pigs and humans (in control settings, not exposed to conducted electrical weapons). The lack of significant changes in plasma proteins may be added to the body of evidence regarding relative safety of TASER C2 device exposures.

Exposure caused by wireless technologies used for short-range indoor communication in homes and offices.

PubMed

Schmid, G; Lager, D; Preiner, P; Uberbacher, R; Cecil, S

2007-01-01

In order to estimate typical radio frequency exposures from indoor used wireless communication technologies applied in homes and offices, WLAN, Bluetooth and Digital Enhanced Cordless Telecommunications systems, as well as baby surveillance devices and wireless headphones for indoor usage, have been investigated by measurements and numerical computations. Based on optimised measurement methods, field distributions and resulting exposure were assessed on selected products and real exposure scenarios. Additionally, generic scenarios have been investigated on the basis of numerical computations. The obtained results demonstrate that under usual conditions the resulting spatially (over body dimensions) averaged and 6-min time-averaged exposure for persons in the radio frequency fields of the considered applications is below approximately 0.1% of the reference level for power density according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines published in 1998. Spatial and temporal peak values can be considerably higher by 2-3 orders of magnitude. In case of some transmitting devices operated in close proximity to the body (e.g. WLAN transmitters), local exposure can reach the same order of magnitude as the basic restriction; however, none of the devices considered in this study exceeded the limits according to the ICNIRP guidelines.

Thermoelectric microdevice fabricated by a MEMS-like electrochemical process

NASA Technical Reports Server (NTRS)

Snyder, G. Jeffrey; Lim, James R.; Huang, Chen-Kuo; Fleurial, Jean-Pierre

2003-01-01

Microelectromechanical systems (MEMS) are the basis of many rapidly growing technologies, because they combine miniature sensors and actuators with communications and electronics at low cost. Commercial MEMS fabrication processes are limited to silicon-based materials or two-dimensional structures. Here we show an inexpensive, electrochemical technique to build MEMS-like structures that contain several different metals and semiconductors with three-dimensional bridging structures. We demonstrate this technique by building a working microthermoelectric device. Using repeated exposure and development of multiple photoresist layers, several different metals and thermoelectric materials are fabricated in a three-dimensional structure. A device containing 126 n-type and p-type (Bi, Sb)2Te3 thermoelectric elements, 20 microm tall and 60 microm in diameter with bridging metal interconnects, was fabricated and cooling demonstrated. Such a device should be of technological importance for precise thermal control when operating as a cooler, and for portable power when operating as a micro power generator.

Design Considerations and Performance of MEMS Acoustoelectric Ultrasound Detectors

PubMed Central

Wang, Zhaohui; Ingram, Pier; Greenlee, Charles L.; Olafsson, Ragnar; Norwood, Robert A.; Witte, Russell S.

2014-01-01

Most single-element hydrophones depend on a piezoelectric material that converts pressure changes to electricity. These devices, however, can be expensive, susceptible to damage at high pressure, and/or have limited bandwidth and sensitivity. We have previously described the acoustoelectric (AE) hydrophone as an inexpensive alternative for mapping an ultrasound beam and monitoring acoustic exposure. The device exploits the AE effect, an interaction between electrical current flowing through a material and a propagating pressure wave. Previous designs required imprecise fabrication methods using common laboratory supplies, making it difficult to control basic features such as shape and size. This study describes a different approach based on microelectromechanical systems (MEMS) processing that allows for much finer control of several design features. In an effort to improve the performance of the AE hydrophone, we combine simulations with bench-top testing to evaluate key design features, such as thickness, shape, and conductivity of the active and passive elements. The devices were evaluated in terms of sensitivity, frequency response, and accuracy for reproducing the beam pattern. Our simulations and experimental results both indicated that designs using a combination of indium tin oxide (ITO) for the active element and gold for the passive electrodes (conductivity ratio = ~20) produced the best result for mapping the beam of a 2.25-MHz ultrasound transducer. Also, the AE hydrophone with a rectangular dumbbell configuration achieved a better beam pattern than other shape configurations. Lateral and axial resolutions were consistent with images generated from a commercial capsule hydrophone. Sensitivity of the best-performing device was 1.52 nV/Pa at 500 kPa using a bias voltage of 20 V. We expect a thicker AE hydrophone closer to half the acoustic wavelength to produce even better sensitivity, while maintaining high spectral bandwidth for characterizing medical ultrasound transducers. AE ultrasound detectors may also be useful for monitoring acoustic exposure during therapy or as receivers for photoacoustic imaging. PMID:24658721

Automatic exposure control calibration and optimisation for abdomen, pelvis and lumbar spine imaging with an Agfa computed radiography system.

PubMed

Moore, C S; Wood, T J; Avery, G; Balcam, S; Needler, L; Joshi, H; Saunderson, J R; Beavis, A W

2016-11-07

The use of three physical image quality metrics, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQ m ) have recently been examined by our group for their appropriateness in the calibration of an automatic exposure control (AEC) device for chest radiography with an Agfa computed radiography (CR) imaging system. This study uses the same methodology but investigates AEC calibration for abdomen, pelvis and spine CR imaging. AEC calibration curves were derived using a simple uniform phantom (equivalent to 20 cm water) to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated abdomen, pelvis and spine images (created from real patient CT datasets) with appropriate detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated images contained clinically realistic projected anatomy and were scored by experienced image evaluators. Constant DDI and CNR curves did not provide optimized performance but constant eNEQ m and SNR did, with the latter being the preferred calibration metric given that it is easier to measure in practice. This result was consistent with the previous investigation for chest imaging with AEC devices. Medical physicists may therefore use a simple and easily accessible uniform water equivalent phantom to measure the SNR image quality metric described here when calibrating AEC devices for abdomen, pelvis and spine imaging with Agfa CR systems, in the confidence that clinical image quality will be sufficient for the required clinical task. However, to ensure appropriate levels of detector air kerma the advice of expert image evaluators must be sought.

Automatic exposure control calibration and optimisation for abdomen, pelvis and lumbar spine imaging with an Agfa computed radiography system

NASA Astrophysics Data System (ADS)

Moore, C. S.; Wood, T. J.; Avery, G.; Balcam, S.; Needler, L.; Joshi, H.; Saunderson, J. R.; Beavis, A. W.

2016-11-01

The use of three physical image quality metrics, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQm) have recently been examined by our group for their appropriateness in the calibration of an automatic exposure control (AEC) device for chest radiography with an Agfa computed radiography (CR) imaging system. This study uses the same methodology but investigates AEC calibration for abdomen, pelvis and spine CR imaging. AEC calibration curves were derived using a simple uniform phantom (equivalent to 20 cm water) to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated abdomen, pelvis and spine images (created from real patient CT datasets) with appropriate detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated images contained clinically realistic projected anatomy and were scored by experienced image evaluators. Constant DDI and CNR curves did not provide optimized performance but constant eNEQm and SNR did, with the latter being the preferred calibration metric given that it is easier to measure in practice. This result was consistent with the previous investigation for chest imaging with AEC devices. Medical physicists may therefore use a simple and easily accessible uniform water equivalent phantom to measure the SNR image quality metric described here when calibrating AEC devices for abdomen, pelvis and spine imaging with Agfa CR systems, in the confidence that clinical image quality will be sufficient for the required clinical task. However, to ensure appropriate levels of detector air kerma the advice of expert image evaluators must be sought.

Some device implications of voltage controlled magnetic anisotropy in Co/Gd2O3 thin films through REDOX chemistry

NASA Astrophysics Data System (ADS)

Hao, Guanhua; Noviasky, Nicholas; Cao, Shi; Sabirianov, Ildar; Yin, Yuewei; Ilie, Carolina C.; Kirianov, Eugene; Sharma, Nishtha; Sokolov, Andrei; Marshall, Andrew; Xu, Xiaoshan; Dowben, Peter A.

2018-04-01

The effect of intermediate interfacial oxidation on the in-plane magnetization of multilayer stack Pt/Co/Gd2O3, on a p-type silicon substrate, has been investigated by magneto-optical Kerr effect (MOKE) measurements, the anomalous Hall effect, and magnetoresistance measurements. While voltage controlled perpendicular magnetic anisotropy of a metal/oxide heterostructure is known, this heterostructure displays an inverse relationship between voltage and coercivity. The anomalous Hall effect demonstrates a significant change in hysteresis, with the applied bias sign. There is a higher perpendicular magnetic anisotropy with positive bias exposure.

Printing line/space patterns on nonplanar substrates using a digital micromirror device-based point-array scanning technique

NASA Astrophysics Data System (ADS)

Kuo, Hung-Fei; Kao, Guan-Hsuan; Zhu, Liang-Xiu; Hung, Kuo-Shu; Lin, Yu-Hsin

2018-02-01

This study used a digital micromirror device (DMD) to produce point-array patterns and employed a self-developed optical system to define line-and-space patterns on nonplanar substrates. First, field tracing was employed to analyze the aerial images of the lithographic system, which comprised an optical system and the DMD. Multiobjective particle swarm optimization was then applied to determine the spot overlapping rate used. The objective functions were set to minimize linewidth and maximize image log slope, through which the dose of the exposure agent could be effectively controlled and the quality of the nonplanar lithography could be enhanced. Laser beams with 405-nm wavelength were employed as the light source. Silicon substrates coated with photoresist were placed on a nonplanar translation stage. The DMD was used to produce lithographic patterns, during which the parameters were analyzed and optimized. The optimal delay time-sequence combinations were used to scan images of the patterns. Finally, an exposure linewidth of less than 10 μm was successfully achieved using the nonplanar lithographic process.

Impairment of chondrocyte biosynthetic activity by exposure to 3-tesla high-field magnetic resonance imaging is temporary

PubMed Central

Sunk, Ilse-Gerlinde; Trattnig, Siegfried; Graninger, Winfried B; Amoyo, Love; Tuerk, Birgit; Steiner, Carl-Walter; Smolen, Josef S; Bobacz, Klaus

2006-01-01

The influence of magnetic resonance imaging (MRI) devices at high field strengths on living tissues is unknown. We investigated the effects of a 3-tesla electromagnetic field (EMF) on the biosynthetic activity of bovine articular cartilage. Bovine articular cartilage was obtained from juvenile and adult animals. Whole joints or cartilage explants were subjected to a pulsed 3-tesla EMF; controls were left unexposed. Synthesis of sulfated glycosaminoglycans (sGAGs) was measured by using [35S]sulfate incorporation; mRNA encoding the cartilage markers aggrecan and type II collagen, as well as IL-1β, were analyzed by RT–PCR. Furthermore, effects of the 3-tesla EMF were determined over the course of time directly after exposure (day 0) and at days 3 and 6. In addition, the influence of a 1.5-tesla EMF on cartilage sGAG synthesis was evaluated. Chondrocyte cell death was assessed by staining with Annexin V and TdT-mediated dUTP nick end labelling (TUNEL). Exposure to the EMF resulted in a significant decrease in cartilage macromolecule synthesis. Gene expression of both aggrecan and IL-1β, but not of collagen type II, was reduced in comparison with controls. Staining with Annexin V and TUNEL revealed no evidence of cell death. Interestingly, chondrocytes regained their biosynthetic activity within 3 days after exposure, as shown by proteoglycan synthesis rate and mRNA expression levels. Cartilage samples exposed to a 1.5-tesla EMF remained unaffected. Although MRI devices with a field strength of more than 1.5 T provide a better signal-to-noise ratio and thereby higher spatial resolution, their high field strength impairs the biosynthetic activity of articular chondrocytes in vitro. Although this decrease in biosynthetic activity seems to be transient, articular cartilage exposed to high-energy EMF may become vulnerable to damage. PMID:16831232

Impairment of chondrocyte biosynthetic activity by exposure to 3-tesla high-field magnetic resonance imaging is temporary.

PubMed

Sunk, Ilse-Gerlinde; Trattnig, Siegfried; Graninger, Winfried B; Amoyo, Love; Tuerk, Birgit; Steiner, Carl-Walter; Smolen, Josef S; Bobacz, Klaus

2006-01-01

The influence of magnetic resonance imaging (MRI) devices at high field strengths on living tissues is unknown. We investigated the effects of a 3-tesla electromagnetic field (EMF) on the biosynthetic activity of bovine articular cartilage. Bovine articular cartilage was obtained from juvenile and adult animals. Whole joints or cartilage explants were subjected to a pulsed 3-tesla EMF; controls were left unexposed. Synthesis of sulfated glycosaminoglycans (sGAGs) was measured by using [35S]sulfate incorporation; mRNA encoding the cartilage markers aggrecan and type II collagen, as well as IL-1beta, were analyzed by RT-PCR. Furthermore, effects of the 3-tesla EMF were determined over the course of time directly after exposure (day 0) and at days 3 and 6. In addition, the influence of a 1.5-tesla EMF on cartilage sGAG synthesis was evaluated. Chondrocyte cell death was assessed by staining with Annexin V and TdT-mediated dUTP nick end labelling (TUNEL). Exposure to the EMF resulted in a significant decrease in cartilage macromolecule synthesis. Gene expression of both aggrecan and IL-1beta, but not of collagen type II, was reduced in comparison with controls. Staining with Annexin V and TUNEL revealed no evidence of cell death. Interestingly, chondrocytes regained their biosynthetic activity within 3 days after exposure, as shown by proteoglycan synthesis rate and mRNA expression levels. Cartilage samples exposed to a 1.5-tesla EMF remained unaffected. Although MRI devices with a field strength of more than 1.5 T provide a better signal-to-noise ratio and thereby higher spatial resolution, their high field strength impairs the biosynthetic activity of articular chondrocytes in vitro. Although this decrease in biosynthetic activity seems to be transient, articular cartilage exposed to high-energy EMF may become vulnerable to damage.

Medical and non-medical protection standards for ultrasound and infrasound.

PubMed

Duck, Francis A

2007-01-01

Protection from inappropriate or hazardous exposure to ultrasound is controlled through international standards and national regulations. IEC standard 60601 part 1 establishes requirements for the mechanical, electrical, chemical and thermal safety for all electro-medical equipment. The associated part 2 standard for diagnostic medical ultrasonic equipment sets no upper limits on ultrasonic exposure. Instead, safety indices are defined that are intended to advise users on the degree of thermal and mechanical hazard. At present the display of these safety indices satisfies regulatory requirements in both the USA and Europe. Nevertheless there are reservations about the effectiveness of this approach to protection management. In the USA, there are national regulatory limits on diagnostic exposure, based on acoustic output from clinical equipment in use over 20 years ago. The IEC 60601 part 2 standard for therapeutic equipment sets 3 W cm(-2) as the limit on acoustic intensity. Transducer surface temperature is controlled for both diagnostic and therapy devices. For airborne ultrasound, interim guidelines on limits of human exposure published by the IRPA are now 2 decades old. A limit on sound pressure level of 100 dB for the general population is recommended. The absence of protection standards for infrasound relates to difficulties in measurement at these low frequencies.

Calcification in Caribbean reef-building corals at high pCO2 levels in a recirculating ocean acidification exposure system.

PubMed

Enzor, Laura A; Hankins, Cheryl; Vivian, Deborah N; Fisher, William S; Barron, Mace G

2018-02-01

Projected increases in ocean p CO 2 levels are anticipated to affect calcifying organisms more rapidly and to a greater extent than other marine organisms. The effects of ocean acidification (OA) have been documented in numerous species of corals in laboratory studies, largely tested using flow-through exposure systems. We developed a recirculating ocean acidification exposure system that allows precise p CO 2 control using a combination of off-gassing measures including aeration, water retention devices, venturi injectors, and CO 2 scrubbing. We evaluated the recirculating system performance in off-gassing effectiveness and maintenance of target p CO 2 levels over an 84-day experiment. The system was used to identify changes in calcification and tissue growth in response to elevated p CO 2 (1000 μatm) in three reef-building corals of the Caribbean: Pseudodiploria clivosa , Montastraea cavernosa , and Orbicella faveolata . All three species displayed an overall increase in net calcification over the 84-day exposure period regardless of p CO 2 level (control +0.28- 1.12 g, elevated p CO 2 +0.18- 1.16 g), and the system was effective at both off-gassing acidified water to ambient p CO 2 levels, and maintaining target elevated p CO 2 levels over the 3-month experiment.

Effects of chronic exposure to electromagnetic waves on the auditory system.

PubMed

Özgür, Abdulkadir; Tümkaya, Levent; Terzi, Suat; Kalkan, Yıldıray; Erdivanlı, Özlem Çelebi; Dursun, Engin

2015-08-01

The results support that chronic electromagnetic field exposure may cause damage by leading to neuronal degeneration of the auditory system. Numerous researches have been done about the risks of exposure to the electromagnetic fields that occur during the use of these devices, especially the effects on hearing. The aim of this study is to evaluate the effects of the electromagnetic waves emitted by the mobile phones through the electrophysiological and histological methods. Twelve adult Wistar albino rats were included in the study. The rats were divided into two groups of six rats. The study group was exposed to the electromagnetic waves over a period of 30 days. The control group was not given any exposure to the electromagnetic fields. After the completion of the electromagnetic wave application, the auditory brainstem responses of both groups were recorded under anesthesia. The degeneration of cochlear nuclei was graded by two different histologists, both of whom were blinded to group information. The histopathologic and immunohistochemical analysis showed neuronal degeneration signs, such as increased vacuolization in the cochlear nucleus, pyknotic cell appearance, and edema in the group exposed to the electromagnetic fields compared to the control group. The average latency of wave in the ABR was similar in both groups (p > 0.05).

Cultural and Demographic Factors Influencing Noise Exposure Estimates from Use of Portable Listening Devices in an Urban Environment

ERIC Educational Resources Information Center

Fligor, Brian J.; Levey, Sandra; Levey, Tania

2014-01-01

Purpose: This study examined listening levels and duration of portable listening devices (PLDs) used by people with diversity of ethnicity, education, music genre, and PLD manufacturer. The goal was to estimate participants' PLD noise exposure and identify factors influencing user behavior. Method: This study measured listening levels of 160…

[Biological exposure-related injuries in workers in a health system of the health service of Galicia, Spain].

PubMed

Cores Calvo, Juan; Muñiz Saborido, José Ramón; González Iglesias, Marta Clara

2013-01-01

The objective of this study was to describe the factors involved in biological exposure-related injuries occurring in worker from a health system in Galicia, Spain. The study was conducted in a health system of the Health Service of Galicia, that included four hospitals and 72 primary care centers, with nearly 6000 workers. The study used occupational injury data available o in the injury registry of the Health Service of Galicia for the year 2011. We identified 194 biohazard-related injuries. Exposures, locations, devices, tasks and causes of these incidents were analysed. The majority of biological exposures occurred through needlestick injuries (82%). The areas where more injuries occurred were in inpatient wards (37%) and operating rooms (25%). The devices most frequently involved were suture needles (15%) and insulin needles (15%). The most frequently recorded causes were lack of training and information, together with lack of biosafety devices. Worker training and information should be promoted along with the implementation of biosafety devices, as the latter measure alone does not seem sufficient to reduce the number of injuries. Copyright belongs to the Societat Catalana de Seguretat i Medicina del Treball.

Validation of an Innovative Satellite-Based UV Dosimeter

NASA Astrophysics Data System (ADS)

Morelli, Marco; Masini, Andrea; Simeone, Emilio; Khazova, Marina

2016-08-01

We present an innovative satellite-based UV (ultraviolet) radiation dosimeter with a mobile app interface that has been validated by exploiting both ground-based measurements and an in-vivo assessment of the erythemal effects on some volunteers having a controlled exposure to solar radiation.Both validations showed that the satellite-based UV dosimeter has a good accuracy and reliability needed for health-related applications.The app with this satellite-based UV dosimeter also includes other related functionalities such as the provision of safe sun exposure time updated in real-time and end exposure visual/sound alert. This app will be launched on the global market by siHealth Ltd in May 2016 under the name of "HappySun" and available both for Android and for iOS devices (more info on http://www.happysun.co.uk).Extensive R&D activities are on-going for further improvement of the satellite-based UV dosimeter's accuracy.

Observed use of voluntary controls to reduce physical exposures among sheet metal workers of the mechanical trade

PubMed Central

Dale, Ann Marie; Miller, Kim; Gardner, Bethany T.; Hwang, Ching-Ting; Evanoff, Bradley; Welch, Laura

2015-01-01

Introduction Little is known about the transfer into the workplace of interventions designed to reduce the physical demands of sheet metal workers. Methods We reviewed videos from a case series of 15 sheet metal worksite assessments performed in 2007–2009 to score postures and physical loads, and to observe the use of recommended interventions to reduce physical exposures in sheet metal activities made by a NIOSH stakeholder meeting in 2002. Results Workers showed consistent use of material handling devices, but we observed few uses of recommended interventions to reduce exposures during overhead work. Workers spent large proportions of time in awkward shoulder elevation and low back rotation postures. Conclusions In addition to the development of new technologies and system designs, increased adoption of existing tools and practices could reduce time spent in awkward postures and other risks for musculoskeletal disorders in sheet metal work. PMID:26360196

Validation and in vivo assessment of an innovative satellite-based solar UV dosimeter for a mobile app dedicated to skin health.

PubMed

Morelli, M; Masini, A; Simeone, E; Khazova, M

2016-08-31

We present an innovative satellite-based solar UV (ultraviolet) radiation dosimeter with a mobile app interface that has been validated by exploiting both ground-based measurements and an in vivo assessment of the erythemal effects on some volunteers having controlled exposure to solar radiation. The app with this satellite-based UV dosimeter also includes other related functionalities such as the provision of safe sun exposure time updated in real-time and end exposure visual/sound alert. Both validations showed that the system has a good accuracy and reliability needed for health-related applications. This app will be launched on the market by siHealth Ltd in May 2016 under the name of "HappySun" and is available for both Android and iOS devices (more info on ). Extensive R&D activities are on-going for the further improvement of the satellite-based UV dosimeter's accuracy.

Self-Limiting Oxides on WSe2 as Controlled Surface Acceptors and Low-Resistance Hole Contacts.

PubMed

Yamamoto, Mahito; Nakaharai, Shu; Ueno, Keiji; Tsukagoshi, Kazuhito

2016-04-13

Transition metal oxides show much promise as effective p-type contacts and dopants in electronics based on transition metal dichalcogenides. Here we report that atomically thin films of under-stoichiometric tungsten oxides (WOx with x < 3) grown on tungsten diselenide (WSe2) can be used as both controlled charge transfer dopants and low-barrier contacts for p-type WSe2 transistors. Exposure of atomically thin WSe2 transistors to ozone (O3) at 100 °C results in self-limiting oxidation of the WSe2 surfaces to conducting WOx films. WOx-covered WSe2 is highly hole-doped due to surface electron transfer from the underlying WSe2 to the high electron affinity WOx. The dopant concentration can be reduced by suppressing the electron affinity of WOx by air exposure, but exposure to O3 at room temperature leads to the recovery of the electron affinity. Hence, surface transfer doping with WOx is virtually controllable. Transistors based on WSe2 covered with WOx show only p-type conductions with orders of magnitude better on-current, on/off current ratio, and carrier mobility than without WOx, suggesting that the surface WOx serves as a p-type contact with a low hole Schottky barrier. Our findings point to a simple and effective strategy for creating p-type devices based on two-dimensional transition metal dichalcogenides with controlled dopant concentrations.

Exposure Assessment of a High-energy Tensile Test With Large Carbon Fiber Reinforced Polymer Cables.

PubMed

Schlagenhauf, Lukas; Kuo, Yu-Ying; Michel, Silvain; Terrasi, Giovanni; Wang, Jing

2015-01-01

This study investigated the particle and fiber release from two carbon fiber reinforced polymer cables that underwent high-energy tensile tests until rupture. The failing event was the source of a large amount of dust whereof a part was suspected to be containing possibly respirable fibers that could cause adverse health effects. The released fibers were suspected to migrate through small openings to the experiment control room and also to an adjacent machine hall where workers were active. To investigate the fiber release and exposure risk of the affected workers, the generated particles were measured with aerosol devices to obtain the particle size and particle concentrations. Furthermore, particles were collected on filter samples to investigate the particle shape and the fiber concentration. Three situations were monitored for the control room and the machine hall: the background concentrations, the impact of the cable failure, and the venting of the exposed rooms afterward. The results showed four important findings: The cable failure caused the release of respirable fibers with diameters below 3 μm and an average length of 13.9 μm; the released particles did migrate to the control room and to the machine hall; the measured peak fiber concentration of 0.76 fibers/cm(3) and the overall fiber concentration of 0.07 fibers/cm(3) in the control room were below the Permissible Exposure Limit (PEL) for fibers without indication of carcinogenicity; and the venting of the rooms was fast and effective. Even though respirable fibers were released, the low fiber concentration and effective venting indicated that the suspected health risks from the experiment on the affected workers was low. However, the effect of long-term exposure is not known therefore additional control measures are recommended.

Automating Microbial Directed Evolution For Bioengineering Applications

NASA Astrophysics Data System (ADS)

Lee, A.; Demachkie, I. S.; Sardesh, N.; Arismendi, D.; Ouandji, C.; Wang, J.; Blaich, J.; Gentry, D.

2016-12-01

From a micro-biology perspective, directed evolution is a technique that uses controlled environmental pressures to select for a desired phenotype. Directed evolution has the distinct advantage over rational design of not needing extensive knowledge of the genome or pathways associated with a microorganism to induce phenotypes. However, there are currently limitations to the applicability of this technique including being time-consuming, error-prone, and dependent on existing assays that may lack selectivity for the given phenotype. The AADEC (Autonomous Adaptive Directed Evolution Chamber) system is a proof-of-concept instrument to automate and improve the technique such that directed evolution can be used more effectively as a general bioengineering tool. A series of tests using the automated system and comparable by-hand survival assay measurements have been carried out using UV-C radiation and Escherichia coli cultures in order to demonstrate the advantages of the AADEC versus traditional implementations of directed evolution such as random mutagenesis. AADEC uses UV-C exposure as both a source of environmental stress and mutagenesis, so in order to evaluate the UV-C tolerance obtained from the cultures, a manual UV-C exposure survival assay was developed alongside the device to compare the survival fractions at a fixed dosage. This survival assay involves exposing E.coli to UV-C radiation using a custom-designed exposure hood to control the flux and dose. Surviving cells are counted then transferred to the next iteration and so on for several iterations to calculate the survival fractions for each exposure iteration. This survival assay primarily serves as a baseline for the AADEC device, allowing quantification of the differences between the AADEC system over the manual approach. The primary data of comparison is survival fractions; this is obtained by optical density and plate counts in the manual assay and by optical density growth curve fits pre- and post-exposure in the automated case. This data can then be compiled to calculate trends over the iterations to characterize increasing UV-C resistance of the E.coli strains. The observed trends are statistically indistinguishable through several iterations from both sources.

Effects of low intensity static electromagnetic radiofrequency fields on leiomyosarcoma and smooth muscle cell lines.

PubMed

Karkabounas, Spyridon; Havelas, Konstantinos; Kostoula, Olga K; Vezyraki, Patra; Avdikos, Antonios; Binolis, Jayne; Hatziavazis, George; Metsios, Apostolos; Verginadis, Ioannis; Evangelou, Angelos

2006-01-01

In this study we investigated the effects of low intensity static radiofrequency electromagnetic field (EMF) causing no thermal effects, on leiomyosarcoma cells (LSC), isolated from tumors of fifteen Wistar rats induced via a 3,4-benzopyrene injection. Electromagnetic resonance frequencies measurements and exposure of cells to static EMF were performed by a device called multi channel dynamic exciter 100 V1 (MCDE). The LSC were exposed to electromagnetic resonance radiofrequencies (ERF) between 10 kHz to 120 kHz, for 45 min. During a 24h period, after the exposure of the LSC to ERF, there was no inhibition of cells proliferation. In contrast, at the end of a 48 h incubation period, LSC proliferation dramatically decreased by more than 98% (P<0.001). At that time, the survived LSC were only 2% of the total cell population exposed to ERF, and under the same culture conditions showed significant decrease of proliferation. These cells were exposed once again to ERF for 45 min (totally 4 sessions of exposure, of 45 min duration each) and tested using a flow cytometer. Experiments as above were repeated five times. It was found that 45% of these double exposed to ERF, LSC (EMF cells) were apoptotic and only a small percentage 2%, underwent mitosis. In order to determinate their metastatic potential, these EMF cells were also counted and tested by an aggregometer for their ability to aggregate platelets and found to maintain this ability., since they showed no difference in platelet aggregation ability compared to the LSC not exposed to ERF (control cells). In conclusion, exposure of LSC to specific ERF, decreases their proliferation rate and induces cell apoptosis. Also, the LSC that survived after exposed to ERF, had a lower proliferation rate compared to the LSC controls (P<0.05) but did not loose their potential for metastases (platelet aggregation ability). The non-malignant SMC were not affected by the EMF exposure (P<0.4). The specific ERF generated from the MCDE electronic device, used in this study, is safe for humans and animals, according to the international safety standards.

Potential Effectiveness of Point-of-Use Filtration to Address Risks to Drinking Water in the United States

PubMed Central

Brown, Kathleen Ward; Gessesse, Bemnet; Butler, Lindsey J; MacIntosh, David L

2017-01-01

Numerous contemporary incidents demonstrate that conventional control strategies for municipal tap water have limited ability to mitigate exposures to chemicals whose sources are within distribution systems, such as lead, and chemicals that are not removed by standard treatment technologies, such as perfluorooctanoic acid (PFOA)/perfluorooctanesulfonic acid (PFOS). In these situations, point-of-use (POU) controls may be effective in mitigating exposures and managing health risks of chemicals in drinking water, but their potential utility has not been extensively examined. As an initial effort to fill this information gap, we conducted a critical review and analysis of the existing literature and data on the effectiveness of POU drinking water treatment technologies for reducing chemical contaminants commonly found in tap water in the United States. We found that many types of water treatment devices available to consumers in the United States have undergone laboratory testing and often certification for removal of chemical contaminants in tap water, but in most cases their efficacy in actual use has yet to be well characterized. In addition, the few studies of POU devices while “in use” focus on traditional contaminants regulated under the Safe Drinking Water Act, but do not generally consider nontraditional contaminants of concern, such as certain novel human carcinogens, industrial chemicals, pesticides, pharmaceuticals, personal care products, and flame retardants. Nevertheless, the limited information available at present suggests that POU devices can be highly effective when used prophylactically and when deployed in response to contamination incidents. Based on these findings, we identify future areas of research for assessing the ability of POU filters to reduce health-related chemical contaminants distributed through public water systems and private wells. PMID:29270018

Hazard zoning around electric substations of petrochemical industries by stimulation of extremely low-frequency magnetic fields.

PubMed

Hosseini, Monireh; Monazzam, Mohammad Reza; Farhang Matin, Laleh; Khosroabadi, Hossein

2015-05-01

Electromagnetic fields in recent years have been discussed as one of the occupational hazards at workplaces. Hence, control and assessment of these physical factors is very important to protect and promote the health of employees. The present study was conducted to determine hazard zones based on assessment of extremely low-frequency magnetic fields at electric substations of a petrochemical complex in southern Iran, using the single-axis HI-3604 device. In measurement of electromagnetic fields by the single-axis HI-3604 device, the sensor screen should be oriented in a way to be perpendicular to the field lines. Therefore, in places where power lines are located in different directions, it is required to keep the device towards three axes of x, y, and z. For further precision, the measurements should be repeated along each of the three axes. In this research, magnetic field was measured, for the first time, in three axes of x, y, and z whose resultant value was considered as the value of magnetic field. Measurements were done based on IEEE std 644-1994. Further, the spatial changes of the magnetic field surrounding electric substations were stimulated using MATLAB software. The obtained results indicated that the maximum magnetic flux density was 49.90 μT recorded from boiler substation, while the minimum magnetic flux density of 0.02 μT was measured at the control room of the complex. As the stimulation results suggest, the spaces around incoming panels, transformers, and cables were recognized as hazardous zones of indoor electric substations. Considering the health effects of chronic exposure to magnetic fields, it would be possible to minimize exposure to these contaminants at workplaces by identification of risky zones and observation of protective considerations.

Potential Effectiveness of Point-of-Use Filtration to Address Risks to Drinking Water in the United States.

PubMed

Brown, Kathleen Ward; Gessesse, Bemnet; Butler, Lindsey J; MacIntosh, David L

2017-01-01

Numerous contemporary incidents demonstrate that conventional control strategies for municipal tap water have limited ability to mitigate exposures to chemicals whose sources are within distribution systems, such as lead, and chemicals that are not removed by standard treatment technologies, such as perfluorooctanoic acid (PFOA)/perfluorooctanesulfonic acid (PFOS). In these situations, point-of-use (POU) controls may be effective in mitigating exposures and managing health risks of chemicals in drinking water, but their potential utility has not been extensively examined. As an initial effort to fill this information gap, we conducted a critical review and analysis of the existing literature and data on the effectiveness of POU drinking water treatment technologies for reducing chemical contaminants commonly found in tap water in the United States. We found that many types of water treatment devices available to consumers in the United States have undergone laboratory testing and often certification for removal of chemical contaminants in tap water, but in most cases their efficacy in actual use has yet to be well characterized. In addition, the few studies of POU devices while "in use" focus on traditional contaminants regulated under the Safe Drinking Water Act, but do not generally consider nontraditional contaminants of concern, such as certain novel human carcinogens, industrial chemicals, pesticides, pharmaceuticals, personal care products, and flame retardants. Nevertheless, the limited information available at present suggests that POU devices can be highly effective when used prophylactically and when deployed in response to contamination incidents. Based on these findings, we identify future areas of research for assessing the ability of POU filters to reduce health-related chemical contaminants distributed through public water systems and private wells.

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

PubMed

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.

Molecular and epidemiological characterization of IMP-type metallo-β-lactamase-producing Enterobacter cloacae in a Large tertiary care hospital in Japan.

PubMed

Hayakawa, Kayoko; Miyoshi-Akiyama, Tohru; Kirikae, Teruo; Nagamatsu, Maki; Shimada, Kayo; Mezaki, Kazuhisa; Sugiki, Yuko; Kuroda, Emi; Kubota, Shiho; Takeshita, Nozomi; Kutsuna, Satoshi; Tojo, Masayoshi; Ohmagari, Norio

2014-06-01

IMP-type metallo-β-lactamase enzymes have been reported in different geographical areas and in various Gram-negative bacteria. However, the risk factors and epidemiology pertaining to IMP-type metallo-β-lactamase-producing Enterobacter cloacae (IMP-producing E. cloacae) have not been systematically evaluated. We conducted a retrospective, matched case-control study of patients from whom IMP-producing E. cloacae isolates were obtained, in addition to performing thorough molecular analyses of the clinically obtained IMP-producing E. cloacae isolates. Unique cases with IMP-producing E. cloacae isolation were included. Patients with IMP-producing E. cloacae were matched to uninfected controls at a ratio of 1 to 3. Fifteen IMP-producing E. cloacae cases were identified, with five of the isolates being obtained from blood, and they were matched to 45 uninfected controls. All (100%) patients from whom IMP-producing E. cloacae isolates were obtained had indwelling devices at the time of isolation, compared with one (2.2%) uninfected control. Independent predictors for isolation of IMP-producing E. cloacae were identified as cephalosporin exposure and invasive procedures within 3 months. Although in-hospital mortality rates were similar between cases and controls (14.3% versus 13.3%), the in-hospital mortality of patients with IMP-producing E. cloacae-caused bacteremia was significantly higher (40%) than the rate in controls. IMP-producing E. cloacae isolates were frequently positive for other resistance determinants. The MICs of meropenem and imipenem were not elevated; 10 (67%) and 12 (80%) of the 15 IMP-producing E. cloacae isolates had a MIC of ≤ 1 μg/ml. A phylogenetic tree showed a close relationship among the IMP-producing E. cloacae samples. Indwelling devices, exposure to cephalosporin, and a history of invasive procedures were associated with isolation of IMP-producing E. cloacae. Screening for carbapenemase production is important in order to apply appropriate clinical management and infection control measures. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Biomonitoring of a worker population exposed to platinum dust in a catalyst production plant

PubMed Central

Petrucci, F; Violante, N; Senofonte, O; Cristaudo, A; Di, G; Forte, G; Alimonti, A

2005-01-01

Aims: To evaluate the occupational exposure to platinum in an industrial plant engaged in the production, recovery, and recycling of catalytic converters for the automotive traction and chemical industries. Methods: Pt was determined in airborne particulate matter, and blood, urine, and hair of 106 exposed workers, 21 controls from the plant's administrative offices, and 25 unexposed subjects. Results: The highest air Pt level was found in the department of the plant in which supports are coated with acid metal solutions, where values of 2.39 and 4.83 µg/m3 respectively were found in environmental airborne particulate matter and in air collected using personal sampler devices. The percentage of soluble Pt was also highest in this area, varying from 24% to 44% of the total. The biological data confirmed this trend, with mean concentrations in this site being higher than in other working areas: 1.86 µg/l (urine), 0.38 µg/l (blood), and 2.26 µg/kg (hair). The workers employed in the administrative sector, who were not directly exposed to Pt, had levels of contaminant lower than those of other workers, albeit 2–20 times higher than those of external controls. High correlations were obtained between Pt levels detected in airborne samples using personal devices and those found in urine and hair, but not in blood. Conclusions: The background level of Pt in all areas of the factory implies widespread exposure for the workers. The most reliable biomarker was urine. Hair cannot be considered a good index of time related exposure, at least until more reliable methods of washing can be found that are able to remove exogenous Pt completely. PMID:15613605

Exposure to sunlamps, tanning beds, and melanoma risk.

PubMed

Clough-Gorr, Kerri M; Titus-Ernstoff, Linda; Perry, Ann E; Spencer, Steven K; Ernstoff, Marc S

2008-09-01

To estimate the separate effects of sunlamp and tanning bed device use on melanoma risk. Population-based case-control study of 423 cases of melanoma and 678 controls in the state of New Hampshire. Exposure data, including sunlamp and tanning bed use, were collected by telephone interview. Associations were evaluated using logistic regression analyses. About 17% of participants ever used a sunlamp, and most use (89%) occurred before 1980. The OR was 1.39 (95% CI 1.00-1.96) for ever using a sunlamp, 1.23 (95% CI 0.81-1.88) for those starting sunlamp use <20 years, and 1.71 (95% CI 1.00-2.92) for those starting >/=20 years. Data suggested increasing risk with number of sunlamp uses and with duration of use (tests of trend p = 0.02). The overall prevalence of tanning bed use was 22% and most use (83%) occurred after 1980. The OR was 1.14 (95% CI 0.80-1.61) for ever using a tanning bed; there was no evidence that risk increased with frequency or duration of use. The OR was 1.96 (95% CI 1.06-3.61) for having used both devices. Results suggest a modest association between sunlamp use and melanoma risk, and increasing risk with greater frequency and duration of use. No association with tanning bed use was found, but sufficient lag time may not have elapsed to assess a potential effect.

Controlled loading of cryoprotectants (CPAs) to oocyte with linear and complex CPA profiles on a microfluidic platform.

PubMed

Heo, Yun Seok; Lee, Ho-Joon; Hassell, Bryan A; Irimia, Daniel; Toth, Thomas L; Elmoazzen, Heidi; Toner, Mehmet

2011-10-21

Oocyte cryopreservation has become an essential tool in the treatment of infertility by preserving oocytes for women undergoing chemotherapy. However, despite recent advances, pregnancy rates from all cryopreserved oocytes remain low. The inevitable use of the cryoprotectants (CPAs) during preservation affects the viability of the preserved oocytes and pregnancy rates either through CPA toxicity or osmotic injury. Current protocols attempt to reduce CPA toxicity by minimizing CPA concentrations, or by minimizing the volume changes via the step-wise addition of CPAs to the cells. Although the step-wise addition decreases osmotic shock to oocytes, it unfortunately increases toxic injuries due to the long exposure times to CPAs. To address limitations of current protocols and to rationally design protocols that minimize the exposure to CPAs, we developed a microfluidic device for the quantitative measurements of oocyte volume during various CPA loading protocols. We spatially secured a single oocyte on the microfluidic device, created precisely controlled continuous CPA profiles (step-wise, linear and complex) for the addition of CPAs to the oocyte and measured the oocyte volumetric response to each profile. With both linear and complex profiles, we were able to load 1.5 M propanediol to oocytes in less than 15 min and with a volumetric change of less than 10%. Thus, we believe this single oocyte analysis technology will eventually help future advances in assisted reproductive technologies and fertility preservation.

Interfacial Modifiers

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

Martin, Ina; French, Roger H.

Our project objective in the first and only Budget Period was to demonstrate the potential of nm-scale organofunctional silane coatings as a method of extending the lifetime of PV materials and devices. Specifically, the target was to double the lifetime performance of a laminated Cu(In,Ga)Se2 (CIGS) cell under real-world and accelerated aging exposure conditions. Key findings are that modification of aluminum-doped zinc oxide (AZO) films (materials used as transparent conductive oxide (TCO) top contacts) resulted in decreased degradation of optical and electrical properties under damp heat (DH) exposure compared to un-modified AZO. The most significant finding is that modification ofmore » the AZO top contact of full CIGS devices resulted in significantly improved properties under DH exposure compared to un-modified devices, by a factor of 4 after 1000 h. Results of this one-year project have demonstrated that surface functionalization is a viable pathway for extending the lifetime of state-of-the-art CIGS devices.« less

The Growing Public Health Challenges of Exposure to Ultraviolet Radiation From Use of Indoor Tanning Devices in the United States.

PubMed

Bowman, Diana M; Lewis, Ryan C; Lee, Maximilian S; Yao, Catherine J

2015-08-01

Ultraviolet radiation is recognized as a human carcinogen by the International Agency for Research on Cancer, the world's authority on cancer research. In particular, exposure to ultraviolet radiation can lead to melanoma of the skin, which is the deadliest form of skin cancer in the United States. Yet despite the significant public health burden that is associated with skin cancer in the United States, each year over a million Americans engage in indoor tanning where exposure to artificial ultraviolet radiation occurs. In this article, we argue for an immediate ban on the use of commercial indoor tanning by minors and, based on international precedents, the phasing out of all commercial tanning operations in the United States. We consider the use of indoor tanning devices in the United States, epidemiological data on indoor tanning devices and cancer, regulation of tanning devices, and scientific evidence for increased government intervention. © The Author(s) 2015.

Claims in vapour device (e-cigarette) regulation: A Narrative Policy Framework analysis.

PubMed

O'Leary, Renée; Borland, Ron; Stockwell, Tim; MacDonald, Marjorie

2017-06-01

The electronic cigarette or e-cigarette (vapour device) is a consumer product undergoing rapid growth, and governments have been adopting regulations on the sale of the devices and their nicotine liquids. Competing claims about vapour devices have ignited a contentious debate in the public health community. What claims have been taken up in the state arena, and how have they possibly influenced regulatory outcomes? This study utilized Narrative Policy Framework to analyze the claims made about vapour devices in legislation recommendation reports from Queensland Australia, Canada, and the European Union, and the 2016 deeming rule legislation from the United States, and examined the claims and the regulatory outcomes in these jurisdictions. The vast majority of claims in the policy documents represented vapour devices as a threat: an unsafe product harming the health of vapour device users, a gateway product promoting youth tobacco uptake, and a quasi-tobacco product impeding tobacco control. The opportunity for vapour devices to promote cessation or reduce exposure to toxins was very rarely presented, and these positive claims were not discussed at all in two of the four documents studied. The dominant claims of vapour devices as a public health threat have supported regulations that have limited their potential as a harm reduction strategy. Future policy debates should evaluate the opportunities for vapour devices to decrease the health and social burdens of the tobacco epidemic. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison Of The I-Gel Supraglottic And King Laryngotracheal Airways In A Simulated Tactical Environment.

PubMed

March, Juan A; Tassey, Theresa E; Resurreccion, Noel B; Portela, Roberto C; Taylor, Stephen E

2018-01-01

When working in a tactical environment there are several different airway management options that exist. One published manuscript suggests that when compared to endotracheal intubation, the King LT laryngotracheal airway (KA) device minimizes time to successful tube placement and minimizes exposure in a tactical environment. However, comparison of two different blind insertion supraglottic airway devices in a tactical environment has not been performed. This study compared the I-Gel airway (IGA) to the KA in a simulated tactical environment, to determine if one device is superior in minimizing exposure and minimizing time to successful tube placement. This prospective randomized cross over trial was performed using the same methods and tactical environment employed in a previously published study, which compared endotracheal intubation versus the KA in a tactical environment. The tactical environment was simulated with a one-foot vertical barrier. The participants were paramedic students who wore an Advanced Combat Helmet (ACH) and a ballistic vest (IIIA) during the study. Participants were then randomized to perform tactical airway management on an airway manikin with either the KA or the IGA, and then again using the alternate device. The participants performed a low military type crawl and remained in this low position during each tube placement. We evaluated the time to successful tube placement between the IGA and KA. During attempts, participants were videotaped to monitor their height exposure above the barrier. Following completion, participants were asked which airway device they preferred. Data was analyzed using Student's t-test across the groups for time to ventilation and height of exposure. In total 19 paramedic students who were already at the basic EMT level participated. Time to successful placement for the KA was 39.7 seconds (95%CI: 32.7-46.7) versus 14.4 seconds (95%CI: 12.0-16.9) for the IGA, p < 0.001. Maximum height exposure of the helmet above a one foot vertical barrier for the KA resulted in 1.42 inches of exposure (95%CI: 0.38-0.63) compared to the IGA with 1.42 inches, 95%CI:0.32-0.74, p = 0.99. On questioning 100% of the participants preferred the IGA device over the KA. In a simulated tactical environment placement of the IGA for airway management was faster than with the KA, but there was no difference in regard to exposure. Additionally, all the participants preferred using the IGA device over the KA.

Subcellular glucose exposure biases the spatial distribution of insulin granules in single pancreatic beta cells.

PubMed

Terao, Kyohei; Gel, Murat; Okonogi, Atsuhito; Fuke, Ariko; Okitsu, Teru; Tada, Takashi; Suzuki, Takaaki; Nagamatsu, Shinya; Washizu, Masao; Kotera, Hidetoshi

2014-02-18

In living tissues, a cell is exposed to chemical substances delivered partially to its surface. Such a heterogeneous chemical environment potentially induces cell polarity. To evaluate this effect, we developed a microfluidic device that realizes spatially confined delivery of chemical substances at subcellular resolution. Our microfluidic device allows simple setup and stable operation for over 4 h to deliver chemicals partially to a single cell. Using the device, we showed that subcellular glucose exposure triggers an intracellular [Ca(2+)] change in the β-cells. In addition, the imaging of a cell expressing GFP-tagged insulin showed that continuous subcellular exposure to glucose biased the spatial distribution of insulin granules toward the site where the glucose was delivered. Our approach illustrates an experimental technique that will be applicable to many biological experiments for imaging the response to subcellular chemical exposure and will also provide new insights about the development of polarity of β-cells.

Subcellular glucose exposure biases the spatial distribution of insulin granules in single pancreatic beta cells

PubMed Central

Terao, Kyohei; Gel, Murat; Okonogi, Atsuhito; Fuke, Ariko; Okitsu, Teru; Tada, Takashi; Suzuki, Takaaki; Nagamatsu, Shinya; Washizu, Masao; Kotera, Hidetoshi

2014-01-01

In living tissues, a cell is exposed to chemical substances delivered partially to its surface. Such a heterogeneous chemical environment potentially induces cell polarity. To evaluate this effect, we developed a microfluidic device that realizes spatially confined delivery of chemical substances at subcellular resolution. Our microfluidic device allows simple setup and stable operation for over 4 h to deliver chemicals partially to a single cell. Using the device, we showed that subcellular glucose exposure triggers an intracellular [Ca2+] change in the β-cells. In addition, the imaging of a cell expressing GFP-tagged insulin showed that continuous subcellular exposure to glucose biased the spatial distribution of insulin granules toward the site where the glucose was delivered. Our approach illustrates an experimental technique that will be applicable to many biological experiments for imaging the response to subcellular chemical exposure and will also provide new insights about the development of polarity of β-cells. PMID:24535122

The network approach for prevention of healthcare-associated infections: long-term effect of participation in the Duke Infection Control Outreach Network.

PubMed

Anderson, Deverick J; Miller, Becky A; Chen, Luke F; Adcock, Linda H; Cook, Evelyn; Cromer, A Lynn; Louis, Susan; Thacker, Paul A; Sexton, Daniel J

2011-04-01

To describe the rates of several key outcomes and healthcare-associated infections (HAIs) among hospitals that participated in the Duke Infection Control Outreach Network (DICON). Prospective, observational cohort study of patients admitted to 24 community hospitals from 2003 through 2009. The following data were collected and analyzed: incidence of central line-associated bloodstream infections (CLABSIs), ventilator-associated pneumonia (VAP), catheter-associated urinary tract infections (CAUTIs), and HAIs caused by methicillin-resistant Staphylococcus aureus (MRSA); employee exposures to bloodborne pathogens (EBBPs); physician EBBPs; patient-days; central line-days; ventilator-days; and urinary catheter-days. Poisson regression was used to determine whether incidence rates of these HAIs and exposures changed during the first 5 and 7 years of participation in DICON; nonrandom clustering of each outcome was controlled for. Cost saved and lives saved were calculated on the basis of published estimates. In total, we analyzed 6.5 million patient-days, 4,783 EBPPs, 2,948 HAIs due to MRSA, and 2,076 device-related infections. Rates of employee EBBPs, HAIs due to MRSA, and device-related infections decreased significantly during the first 5 years of participation in DICON (P< .05 for all models; average decrease was approximately 50%); in contrast, physician EBBPs remained unchanged. In aggregate, 210 CLABSIs, 312 cases of VAP, 332 CAUTIs, 1,042 HAIs due to MRSA, and 1,016 employee EBBPs were prevented. Each hospital saved approximately $100,000 per year of participation, and collectively the hospitals may have prevented 52-105 deaths from CLABSI or VAP. The 7-year analysis demonstrated that these trends continued with further participation. Hospitals with long-term participation in an infection control network decreased rates of significant HAIs by approximately 50%, decreased costs, and saved lives.

Experimental investigations of quantum confined silicon nanoparticle light emitting devices

NASA Astrophysics Data System (ADS)

Ligman, Rebekah Kristine

2007-12-01

As the demands on our world's energy resources continue to grow, alternative high efficiency materials such as quantum confined silicon nanoparticles (Si nps) are desirable for their potential low cost application in white light illumination, in optical displays, and in on-chip optical interconnects. Many fabrication and passivation techniques exist that produce Si nps with high photogenerated quantum yield. However, high electrically generated Si np quantum efficiency has eluded our society. Predominantly due to the lack of a stable surface passivation and a device fabrication technique that preserves the Si np optical properties. To amend these deficiencies, the passivation of nonthermal plasma fabricated Si nps with a surface oxide grown under UV exposure was first investigated. Control over the surface oxidized Si np (Si/SiO2) passivation growth was demonstrated and the optical stability of Si/SiO2 nps was suitable for demonstrating Si np electroluminescence (EL). Two approaches for constructing hybrid organic light emitting diode (OLED) devices around nonthermal plasma fabricated Si nps were then investigated. Multilayer devices, composed of a nonthermal plasma fabricated Si np layer embedded within an OLED, were first studied. However, no EL from Si nps was obtained using the multilayer device architecture due to poor control over the Si np film thickness. Single layer polymer(Si/SiO2) hybrid devices, composed of nps randomly dispersed within an extrinsic conductive polymer, were then studied and EL from Si/SiO2 nps was obtained. The hybrid device optical and electrical response was enhanced over the control devices, possibly due to morphology changes induced by the Si/SiO2 nps. The energy transfer (ET) processes in single layer polymer(Si/SiO 2) hybrid devices were then investigated by imposing known spatial separations between the intrinsic conductive polymers and Si/SiO2 nps. No measurable Si/SiO2 np emission was observed from the intrinsic hybrid devices independent of the spatial separation, implying no ET occurs between the intrinsic polymers and Si/SiO2 nps. These results suggest the observed Si/SiO 2 np emission from extrinsic polymer(Si/SiO2) hybrid devices may be produced by direct carrier injection, Forster or Dexter ET mechanisms.

A microfluidic device with multi-valves system to enable several simultaneous exposure tests on Caenorhabditis elegans

NASA Astrophysics Data System (ADS)

Jung, Jaehoon; Nakajima, Masahiro; Masaru, Takeuchi; Huang, Qiang; Fukuda, Toshio

2014-03-01

In this paper, we report on a microfluidic device with a multi-valve system to conduct several exposure tests on Caenorhabditis elegans (C. elegans) simultaneously. It has pneumatic valves and no-moving-parts (NMP) valves. An NMP valve is incorporated with a chamber and enables the unidirectional movement of C. elegans in the chamber; once worms are loaded into the chamber, they cannot exit, regardless of the flow direction. To demonstrate the ability of the NMP valve to handle worms, we made a microfluidic device with three chambers. Each chamber was used to expose worms to Cd and Cu solutions, and K-medium. A pair of electrodes was installed in the device and the capacitance in-between the electrode was measured. When a C. elegans passed through the electrodes, the capacitance was changed. The capacitance change was proportional to the body volume of the worm, thus the body volume change by the heavy metal exposure was measured in the device. Thirty worms were divided into three groups and exposed to each solution. We confirmed that the different solutions induced differences in the capacitance changes for each group. These results indicate that our device is a viable method for simultaneously analyzing the effect of multiple stimuli on C. elegans.

Self-aligned photolithography for the fabrication of fully transparent high-voltage devices

NASA Astrophysics Data System (ADS)

Zhang, Yonghui; Mei, Zengxia; Huo, Wenxing; Wang, Tao; Liang, Huili; Du, Xiaolong

2018-05-01

High-voltage devices, working in the range of hundreds of volts, are indispensable elements in the driving or readout circuits for various kinds of displays, integrated microelectromechanical systems and x-ray imaging sensors. However, the device performances are found hardly uniform or repeatable due to the misalignment issue, which are extremely common for offset drain high-voltage devices. To resolve this issue, this article reports a set of self-aligned photolithography technology for the fabrication of high-voltage devices. High-performance fully-transparent high-voltage thin film transistors, diodes and logic inverters are successfully fabricated with this technology. Unlike other self-aligned routes, opaque masks are introduced on the backside of the transparent substrate to facilitate proximity exposure method. The photolithography process is simulated and analyzed with technology computer aided design simulation to explain the working principle of the proximity exposure method. The substrate thickness is found to be vital for the implementation of this technology based on both simulation and experimental results. The electrical performance of high-voltage devices is dependent on the offset length, which can be delicately modulated by changing the exposure dose. The presented self-aligned photolithography technology is proved to be feasible in high-voltage circuits, demonstrating its huge potential in practical industrial applications.

Process solutions for reducing PR residue over non-planar wafer

NASA Astrophysics Data System (ADS)

Lin, C. H.; Huang, C. H.; Yang, Elvis; Yang, T. H.; Chen, K. C.; Lu, Chih-Yuan

2011-03-01

SAS (Self-Aligned Source) process has been widely adopted on manufacturing NOR Flash devices. To form the SAS structure, the compromise between small space patterning and sufficiently removing photo resist residue in topographical substrate has been a critical challenge as the device scaling down. In this study, photo simulation, layout optimization, resist processing and tri-layer materials were evaluated to form defect-free and highly extendible SAS structure for NOR Flash devices. Photo simulation suggested more coherent light source allowed the incident light to reach the trench bottom that facilitates the removal of photo resist. Mask bias also benefited the process latitude extension for residue-free SAS printing. In the photo resist processing, both lowering the SB (Soft Bake) and raising PEB (Post-Exposure Bake) temperature of photo resist were helpful to broaden the process window but the final pattern profile was not good enough. Thermal flow for pos-exposure pattern shrinkage achieved small CD (Critical Dimension) patterning with residue-free, however the materials loading effect is another issue to be addressed at memory array boundary. Tri-layer scheme demonstrated good results in terms of free from residue, better substrate reflectivity control, enabling smaller space printing to loosen overlay specification and minimizing the poly gate clipping defect. It was finally proposed to combine with etch effort to from the SAS structure. Besides it is also promising to extend to even smaller technology nodes.

Immunohistopathologic demonstration of deleterious effects on growing rat testes of radiofrequency waves emitted from conventional Wi-Fi devices.

PubMed

Atasoy, Halil I; Gunal, Mehmet Y; Atasoy, Pinar; Elgun, Serenay; Bugdayci, Guler

2013-04-01

To investigate effects on rat testes of radiofrequency radiation emitted from indoor Wi-Fi Internet access devices using 802.11.g wireless standards. Ten Wistar albino male rats were divided into experimental and control groups, with five rats per group. Standard wireless gateways communicating at 2.437 GHz were used as radiofrequency wave sources. The experimental group was exposed to radiofrequency energy for 24 h a day for 20 weeks. The rats were sacrificed at the end of the study. Intracardiac blood was sampled for serum 8-hydroxy-2'-deoxyguanosine levels. Testes were removed and examined histologically and immunohistochemically. Testis tissues were analyzed for malondialdehyde levels and prooxidant-antioxidant enzyme activities. We observed significant increases in serum 8-hydroxy-2'-deoxyguanosine levels and 8-hydroxyguanosine staining in the testes of the experimental group indicating DNA damage due to exposure (p < 0.05). We also found decreased levels of catalase and glutathione peroxidase activity in the experimental group, which may have been due to radiofrequency effects on enzyme activity (p < 0.05). These findings raise questions about the safety of radiofrequency exposure from Wi-Fi Internet access devices for growing organisms of reproductive age, with a potential effect on both fertility and the integrity of germ cells. Copyright © 2012 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Capturing exposures: using automated cameras to document environmental determinants of obesity.

PubMed

Barr, Michelle; Signal, Louise; Jenkin, Gabrielle; Smith, Moira

2015-03-01

Children's exposure to food marketing across multiple everyday settings, a key environmental influence on health, has not yet been objectively documented. Wearable automated cameras (ACs) may have the potential to provide an objective account of this exposure. The purpose of this study is to assess the feasibility of using ACs to document children's exposure to food marketing in multiple settings. A convenience sample of six participants (aged 12) wore a SenseCam device for two full days. Following which, participants attended a focus group to ascertain their experiences of using the device. The collected data were analysed to determine participants' daily and setting specific exposure to 'healthy' and 'unhealthy' food marketing (in minutes). The focus group transcript was analysed using thematic analysis to identify the common themes. Participants collected usable data that could be analysed to determine participant's daily exposure (in minutes) to 'unhealthy' food marketing across a number of everyday settings. Results from the focus group discussion indicated that participants were comfortable wearing the device, after an initial adjustment period. ACs may be an effective tool for documenting children's exposure to food marketing in multiple settings. ACs provide a new method for documenting environmental determinants of obesity and likely other environmental impacts on health. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Does prolonged radiofrequency radiation emitted from Wi-Fi devices induce DNA damage in various tissues of rats?

PubMed

Akdag, Mehmet Zulkuf; Dasdag, Suleyman; Canturk, Fazile; Karabulut, Derya; Caner, Yusuf; Adalier, Nur

2016-09-01

Wireless internet (Wi-Fi) providers have become essential in our daily lives, as wireless technology is evolving at a dizzying pace. Although there are different frequency generators, one of the most commonly used Wi-Fi devices are 2.4GHz frequency generators. These devices are heavily used in all areas of life but the effect of radiofrequency (RF) radiation emission on users is generally ignored. Yet, an increasing share of the public expresses concern on this issue. Therefore, this study intends to respond to the growing public concern. The purpose of this study is to reveal whether long term exposure of 2.4GHz frequency RF radiation will cause DNA damage of different tissues such as brain, kidney, liver, and skin tissue and testicular tissues of rats. The study was conducted on 16 adult male Wistar-Albino rats. The rats in the experimental group (n=8) were exposed to 2.4GHz frequency radiation for over a year. The rats in the sham control group (n=8) were subjected to the same experimental conditions except the Wi-Fi generator was turned off. After the exposure period was complete the possible DNA damage on the rat's brain, liver, kidney, skin, and testicular tissues was detected through the single cell gel electrophoresis assay (comet) method. The amount of DNA damage was measured as percentage tail DNA value. Based on the DNA damage results determined by the single cell gel electrophoresis (Comet) method, it was found that the% tail DNA values of the brain, kidney, liver, and skin tissues of the rats in the experimental group increased more than those in the control group. The increase of the DNA damage in all tissues was not significant (p>0.05). However the increase of the DNA damage in rat testes tissue was significant (p<0.01). In conclusion, long-term exposure to 2.4GHz RF radiation (Wi-Fi) does not cause DNA damage of the organs investigated in this study except testes. The results of this study indicated that testes are more sensitive organ to RF radiation. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of SAR and induced current densities in adults and children exposed to electromagnetic fields from electronic article surveillance devices

NASA Astrophysics Data System (ADS)

Martínez-Búrdalo, M.; Sanchis, A.; Martín, A.; Villar, R.

2010-02-01

Electronic article surveillance (EAS) devices are widely used in most stores as anti-theft systems. In this work, the compliance with international guidelines in the human exposure to these devices is analysed by using the finite-difference time-domain (FDTD) method. Two sets of high resolution numerical phantoms of different size (REMCOM/Hershey and Virtual Family), simulating adult and child bodies, are exposed to a 10 MHz pass-by panel-type EAS consisting of two overlapping current-carrying coils. Two different relative positions between the EAS and the body (frontal and lateral exposures), which imply the exposure of different parts of the body at different distances, have been considered. In all cases, induced current densities in tissues of the central nervous system and specific absorption rates (SARs) are calculated to be compared with the limits from the guidelines. Results show that induced current densities are lower in the case of adult models as compared with those of children in both lateral and frontal exposures. Maximum SAR values calculated in lateral exposure are significantly lower than those calculated in frontal exposure, where the EAS-body distance is shorter. Nevertheless, in all studied cases, with an EAS driving current of 4 A rms, maximum induced current and SAR values are below basic restrictions.

Comparison of SAR and induced current densities in adults and children exposed to electromagnetic fields from electronic article surveillance devices.

PubMed

Martínez-Búrdalo, M; Sanchis, A; Martín, A; Villar, R

2010-02-21

Electronic article surveillance (EAS) devices are widely used in most stores as anti-theft systems. In this work, the compliance with international guidelines in the human exposure to these devices is analysed by using the finite-difference time-domain (FDTD) method. Two sets of high resolution numerical phantoms of different size (REMCOM/Hershey and Virtual Family), simulating adult and child bodies, are exposed to a 10 MHz pass-by panel-type EAS consisting of two overlapping current-carrying coils. Two different relative positions between the EAS and the body (frontal and lateral exposures), which imply the exposure of different parts of the body at different distances, have been considered. In all cases, induced current densities in tissues of the central nervous system and specific absorption rates (SARs) are calculated to be compared with the limits from the guidelines. Results show that induced current densities are lower in the case of adult models as compared with those of children in both lateral and frontal exposures. Maximum SAR values calculated in lateral exposure are significantly lower than those calculated in frontal exposure, where the EAS-body distance is shorter. Nevertheless, in all studied cases, with an EAS driving current of 4 A rms, maximum induced current and SAR values are below basic restrictions.

Performance of GPS-devices for environmental exposure assessment.

PubMed

Beekhuizen, Johan; Kromhout, Hans; Huss, Anke; Vermeulen, Roel

2013-01-01

Integration of individual time-location patterns with spatially resolved exposure maps enables a more accurate estimation of personal exposures to environmental pollutants than using estimates at fixed locations. Current global positioning system (GPS) devices can be used to track an individual's location. However, information on GPS-performance in environmental exposure assessment is largely missing. We therefore performed two studies. First, a commute-study, where the commute of 12 individuals was tracked twice, testing GPS-performance for five transport modes and two wearing modes. Second, an urban-tracking study, where one individual was tracked repeatedly through different areas, focused on the effect of building obstruction on GPS-performance. The median error from the true path for walking was 3.7 m, biking 2.9 m, train 4.8 m, bus 4.9 m, and car 3.3 m. Errors were larger in a high-rise commercial area (median error=7.1 m) compared with a low-rise residential area (median error=2.2 m). Thus, GPS-performance largely depends on the transport mode and urban built-up. Although ~85% of all errors were <10 m, almost 1% of the errors were >50 m. Modern GPS-devices are useful tools for environmental exposure assessment, but large GPS-errors might affect estimates of exposures with high spatial variability.

Cultural and demographic factors influencing noise exposure estimates from use of portable listening devices in an urban environment.

PubMed

Fligor, Brian J; Levey, Sandra; Levey, Tania

2014-08-01

This study examined listening levels and duration of portable listening devices (PLDs) used by people with diversity of ethnicity, education, music genre, and PLD manufacturer. The goal was to estimate participants' PLD noise exposure and identify factors influencing user behavior. This study measured listening levels of 160 adults in 2 New York City locations: (a) a quiet college campus and (b) Union Square, a busy interchange. Participants completed a questionnaire regarding demographics and PLD use. Ordinary least squares regression was used to explore the significance of demographic and behavioral factors. Average listening level was 94.1 dBA, with 99 of 160 (61.9%) and 92 of 159 (57.5%) exceeding daily (L A8hn) and weekly (L Awkn) recommended exposure limit, respectively. African American participants listened at the highest average levels (99.8 dBA). A majority of PLD users exceeded recommended exposure levels. Factors significant for higher exposure were ethnicity and age; factors not significantly associated with exposure were gender, education, location, awareness of possible association between PLD use and noise-induced hearing loss, mode of transportation, device manufacturer, and music genre. Efforts to effect behavior changes to lessen noise-induced hearing loss risk from PLD use should be sensitive to the cultural differences within the targeted population.

Occupational exposure to electromagnetic fields in the Polish Armed Forces.

PubMed

Sobiech, Jaromir; Kieliszek, Jarosław; Puta, Robert; Bartczak, Dagmara; Stankiewicz, Wanda

2017-06-19

Standard devices used by military personnel that may pose electromagnetic hazard include: radars, missile systems, radio navigation systems and radio transceivers. The aim of this study has been to evaluate the exposure of military personnel to electromagnetic fields. Occupational exposure to electromagnetic fields was analyzed in the work environment of personnel of 204 devices divided into 5 groups (surface-to-air missile system radars, aircraft and helicopters, communication devices, surveillance and height finder radars, airport radars and radio navigation systems). Measurements were carried out at indicators, device terminals, radio panels, above vehicle seats, in vehicle hatches, by cabinets containing high power vacuum tubes and other transmitter components, by transmission lines, connectors, etc. Portable radios emit the electric field strength between 20-80 V/m close to a human head. The manpack radio operator's exposure is 60-120 V/m. Inside vehicles with high frequency/very high frequency (HF/VHF) band radios, the electric field strength is between 7-30 V/m and inside the radar cabin it ranges between 9-20 V/m. Most of the personnel on ships are not exposed to the electromagnetic field from their own radar systems but rather by accidental exposure from the radar systems of other ships. Operators of surface-to-air missile systems are exposed to the electric field strength between 7-15 V/m and the personnel of non-directional radio beacons - 100-150 V/m. In 57% of military devices Polish soldiers work in the occupational protection zones. In 35% of cases, soldiers work in intermediate and hazardous zones and in 22% - only in the intermediate zone. In 43% of devices, military personnel are not exposed to electromagnetic field. Int J Occup Med Environ Health 2017;30(4):565-577. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

ICNIRP Statement on Diagnostic Devices Using Non-ionizing Radiation: Existing Regulations and Potential Health Risks.

PubMed

2017-03-01

Use of non-ionizing radiation (NIR) for diagnostic purposes allows non-invasive assessment of the structure and function of the human body and is widely employed in medical care. ICNIRP has published previous statements about the protection of patients during medical magnetic resonance imaging (MRI), but diagnostic methods using other forms of NIR have not been considered. This statement reviews the range of diagnostic NIR devices currently used in clinical settings; documents the relevant regulations and policies covering patients and health care workers; reviews the evidence around potential health risks to patients and health care workers exposed to diagnostic NIR; and identifies situations of high NIR exposure from diagnostic devices in which patients or health care workers might not be adequately protected by current regulations. Diagnostic technologies were classified by the types of NIR that they employ. The aim was to describe the techniques in terms of general device categories which may encompass more specific devices or techniques with similar scientific principles. Relevant legally-binding regulations for protection of patients and workers and organizations responsible for those regulations were summarized. Review of the epidemiological evidence concerning health risks associated with exposure to diagnostic NIR highlighted a lack of data on potential risks to the fetus exposed to MRI during the first trimester, and on long-term health risks in workers exposed to MRI. Most of the relevant epidemiological evidence that is currently available relates to MRI or ultrasound. Exposure limits are needed for exposures from diagnostic technologies using optical radiation within the body. There is a lack of data regarding risk of congenital malformations following exposure to ultrasound in utero in the first trimester and also about the possible health effects of interactions between ultrasound and contrast media.

ICNIRP Statement on Diagnostic Devices Using Non-ionizing Radiation: Existing Regulations and Potential Health Risks

PubMed Central

2017-01-01

Abstract Use of non-ionizing radiation (NIR) for diagnostic purposes allows non-invasive assessment of the structure and function of the human body and is widely employed in medical care. ICNIRP has published previous statements about the protection of patients during medical magnetic resonance imaging (MRI), but diagnostic methods using other forms of NIR have not been considered. This statement reviews the range of diagnostic NIR devices currently used in clinical settings; documents the relevant regulations and policies covering patients and health care workers; reviews the evidence around potential health risks to patients and health care workers exposed to diagnostic NIR; and identifies situations of high NIR exposure from diagnostic devices in which patients or health care workers might not be adequately protected by current regulations. Diagnostic technologies were classified by the types of NIR that they employ. The aim was to describe the techniques in terms of general device categories which may encompass more specific devices or techniques with similar scientific principles. Relevant legally-binding regulations for protection of patients and workers and organizations responsible for those regulations were summarized. Review of the epidemiological evidence concerning health risks associated with exposure to diagnostic NIR highlighted a lack of data on potential risks to the fetus exposed to MRI during the first trimester, and on long-term health risks in workers exposed to MRI. Most of the relevant epidemiological evidence that is currently available relates to MRI or ultrasound. Exposure limits are needed for exposures from diagnostic technologies using optical radiation within the body. There is a lack of data regarding risk of congenital malformations following exposure to ultrasound in utero in the first trimester and also about the possible health effects of interactions between ultrasound and contrast media. PMID:28121732

User-Wearable Devices that Monitor Exposure to Blue Light and Recommend Adjustments Thereto

NASA Technical Reports Server (NTRS)

Lee, Yong Jin (Inventor)

2017-01-01

Described herein are user-wearable devices that include an optical sensor, and methods for use therewith. In certain embodiments, an optical sensor of a user-wearable device (e.g., a wrist-worn device) is used to detect blue light that is incident on the optical sensor and to produce a blue light detection signal indicative thereof, and thus, indicative of the response of the user's intrinsically photosensitive Retinal Ganglion Cells (ipRGCs). In dependence on the blue light detection signal, there is a determination of a metric indicative of an amount of blue light detected by the optical sensor. The metric is compared to a corresponding threshold, and a user notification is triggered in dependence on results of the comparing, wherein the user notification informs a person wearing the user-wearable device to adjust their exposure to light.

Evaluation of Exposure From a Low Energy X-Ray Device Using Thermoluminescent Dosimeters

NASA Technical Reports Server (NTRS)

Edwards, David L.; Harris, William S., Jr.

1997-01-01

The exposure from an electron beam welding device was evaluated using thermoluminescent dosimeters (TLDs). The device generated low energy X-rays which the current dose equivalent conversion algorithm was not designed to evaluate making it necessary to obtain additional information relating to TLD operation at the photon energies encountered with the device. This was accomplished by performing irradiations at the National Institute of Standards and Technology (NIST) using low energy X-ray techniques. The resulting data was used to determine TLD badge response for low energy X-rays and to establish the relationship between TLD element response and the dose equivalent at specific depths in tissue for these photon energies. The new energy/dose equivalent calibration data was used to calculate the shallow and eye dose equivalent of badges exposed to the device.

In situ KPFM imaging of local photovoltaic characteristics of structured organic photovoltaic devices.

PubMed

Watanabe, Satoshi; Fukuchi, Yasumasa; Fukasawa, Masako; Sassa, Takafumi; Kimoto, Atsushi; Tajima, Yusuke; Uchiyama, Masanobu; Yamashita, Takashi; Matsumoto, Mutsuyoshi; Aoyama, Tetsuya

2014-02-12

Here, we discuss the local photovoltaic characteristics of a structured bulk heterojunction, organic photovoltaic devices fabricated with a liquid carbazole, and a fullerene derivative based on analysis by scanning kelvin probe force microscopy (KPFM). Periodic photopolymerization induced by an interference pattern from two laser beams formed surface relief gratings (SRG) in the structured films. The surface potential distribution in the SRGs indicates the formation of donor and acceptor spatial distribution. Under illumination, the surface potential reversibly changed because of the generation of fullerene anions and hole transport from the films to substrates, which indicates that we successfully imaged the local photovoltaic characteristics of the structured photovoltaic devices. Using atomic force microscopy, we confirmed the formation of the SRG because of the material migration to the photopolymerized region of the films, which was induced by light exposure through photomasks. The structuring technique allows for the direct fabrication and the control of donor and acceptor spatial distribution in organic photonic and electronic devices with minimized material consumption. This in situ KPFM technique is indispensable to the fabrication of nanoscale electron donor and electron acceptor spatial distribution in the devices.

Soft X-ray and XUV imaging with a charge-coupled device /CCD/-based detector

NASA Technical Reports Server (NTRS)

Loter, N. G.; Burstein, P.; Krieger, A.; Ross, D.; Harrison, D.; Michels, D. J.

1981-01-01

A soft X-ray/XUV imaging camera which uses a thinned, back-illuminated, all-buried channel RCA CCD for radiation sensing has been built and tested. The camera is a slow-scan device which makes possible frame integration if necessary. The detection characteristics of the device have been tested over the 15-1500 eV range. The response was linear with exposure up to 0.2-0.4 erg/sq cm; saturation occurred at greater exposures. Attention is given to attempts to resolve single photons with energies of 1.5 keV.

SiC Integrated Circuits for Power Device Drivers Able to Operate in Harsh Environments

NASA Astrophysics Data System (ADS)

Godignon, P.; Alexandru, M.; Banu, V.; Montserrat, J.; Jorda, X.; Vellvehi, M.; Schmidt, B.; Michel, P.; Millan, J.

2014-08-01

The currently developed SiC electronic devices are more robust to high temperature operation and radiation exposure damage than correspondingly rated Si ones. In order to integrate the existent SiC high power and high temperature electronics into more complex systems, a SiC integrated circuit (IC) technology capable of operation at temperatures substantially above the conventional ones is required. Therefore, this paper is a step towards the development of ICs-control electronics that have to attend the harsh environment power applications. Concretely, we present the development of SiC MESFET-based digital circuitry, able to integrate gate driver for SiC power devices. Furthermore, a planar lateral power MESFET is developed with the aim of its co-integration on the same chip with the previously mentioned SiC digital ICs technology. And finally, experimental results on SiC Schottky-gated devices irradiated with protons and electrons are presented. This development is based on the Tungsten-Schottky interface technology used for the fabrication of stable SiC Schottky diodes for the European Space Agency Mission BepiColombo.

SHOK—The First Russian Wide-Field Optical Camera in Space

NASA Astrophysics Data System (ADS)

Lipunov, V. M.; Gorbovskoy, E. S.; Kornilov, V. G.; Panasyuk, M. I.; Amelushkin, A. M.; Petrov, V. L.; Yashin, I. V.; Svertilov, S. I.; Vedenkin, N. N.

2018-02-01

Onboard the spacecraft Lomonosov is established two fast, fixed, very wide-field cameras SHOK. The main goal of this experiment is the observation of GRB optical emission before, synchronously, and after the gamma-ray emission. The field of view of each of the cameras is placed in the gamma-ray burst detection area of other devices located onboard the "Lomonosov" spacecraft. SHOK provides measurements of optical emissions with a magnitude limit of ˜ 9-10m on a single frame with an exposure of 0.2 seconds. The device is designed for continuous sky monitoring at optical wavelengths in the very wide field of view (1000 square degrees each camera), detection and localization of fast time-varying (transient) optical sources on the celestial sphere, including provisional and synchronous time recording of optical emissions from the gamma-ray burst error boxes, detected by the BDRG device and implemented by a control signal (alert trigger) from the BDRG. The Lomonosov spacecraft has two identical devices, SHOK1 and SHOK2. The core of each SHOK device is a fast-speed 11-Megapixel CCD. Each of the SHOK devices represents a monoblock, consisting of a node observations of optical emission, the electronics node, elements of the mechanical construction, and the body.

X-ray angiography systems.

PubMed

1993-11-01

Despite the emergence of several alternative angiographic imaging techniques (i.e., magnetic resonance imaging, computed tomography, and ultrasound angiography), x-ray angiography remains the predominant vascular imaging modality, generating over $4 billion in revenue a year in U.S. hospitals. In this issue, we provide a brief overview of the various angiographic imaging techniques, comparing them with x-ray angiography, and discuss the clinical aspects of x-ray vascular imaging, including catheterization and clinical applications. Clinical, cost, usage, and legal issues related to contrast media are discussed in "Contrast Media: Ionic versus Nonionic and Low-osmolality Agents." We also provide a technical overview and selection guidance for a basic x-ray angiography imaging system, including the gantry and table system, x-ray generator, x-ray tube, image intensifier, video camera and display monitors, image-recording devices, and digital acquisition and processing systems. This issue also contains our Evaluation of the GE Advantx L/C cardiac angiography system and the GE Advantx AFM general-purpose angiography system; the AFM can be used for peripheral, pulmonary, and cerebral vascular studied, among others, and can also be configured for cardiac angiography. Many features of the Advantx L/C system, including generator characteristics and ease of use, also apply to the Advantx AFM as configured for cardiac angiography. Our ratings are based on the systems' ability to provide the best possible image quality for diagnosis and therapy while minimizing patient and personnel exposure to radiation, as well as its ability to minimize operator effort and inconvenience. Both units are rated Acceptable. In the Guidance Section, "Radiation Safety and Protection," we discuss the importance of keeping patient and personnel exposures to radiation as low as reasonably possible, especially in procedures such as cardiac catheterization, angiographic imaging for special procedures, and interventional radiology, which produce among the highest radiation exposure of all x-ray imaging techniques. We also provide recommendations for minimizing personnel and patient exposures to radiation. For more information about x-ray angiography systems and similar devices, as well as for additional perspectives on which we based this study, see the following Health Devices Evaluations: "Mobile C-arm Units" (19[8], August 1990) and "Noninvasive Electronic Quality Control Devices for X-ray Generator Testing" (21[6-7], June-July 1992).(ABSTRACT TRUNCATED AT 400 WORDS)

Occupational noise-induced hearing loss in auto part factory workers in welding units in Thailand.

PubMed

Sriopas, Apiradee; Chapman, Robert S; Sutammasa, Saravudh; Siriwong, Wattasit

2017-01-24

Most workers in auto part factories in Thailand are usually exposed to excessive noise in their workplace. This study aimed to assess the level of occupational noise-induced hearing loss and investigate risk factors causing hearing loss in auto part factory workers in the welding units in Thailand. This was a cross-sectional study. One hundred eighty subjects were recruited from 356 workers in the welding unit of three factories. Sixty eligible subjects in each factory were selected by systemic random sampling. The subjects were interviewed using a face-to-face questionnaire. Noise exposure levels and audiograms were measured by a noise dosimeter and an audiometer, respectively. The findings confirmed that noise exposure levels of 86-90 dB (A) and exceeding 90 dB (A) significantly increased the risk of hearing loss in either ear. A noise exposure level exceeding 90 dB (A) significantly increased the prevalence of hearing loss in both ears. Regarding, a 10-pack-year smoking history increased the prevalence of hearing loss in either ear or both ears. In addition, subjects with employment duration exceeding 10 years significantly developed hearing loss in either ear. The engineering control or personal control by wearing hearing protection device should be used to decrease noise exposure levels lower than 85 dB (A) for 8 h. Moreover, if the exposure level reaches 85 dB (A) for 8 h, the employer needs to implement a hearing conservation program in the workplace.

Evaluation of a pulsed xenon ultraviolet light device for isolation room disinfection in a United Kingdom hospital.

PubMed

Hosein, Ian; Madeloso, Rosie; Nagaratnam, Wijayaratnam; Villamaria, Frank; Stock, Eileen; Jinadatha, Chetan

2016-09-01

Pathogen transmission from contaminated surfaces can cause hospital-associated infections. Although pulsed xenon ultraviolet (PX-UV) light devices have been shown to decrease hospital room bioburden in the United States, their effectiveness in United Kingdom (UK) hospitals is less understood. Forty isolation rooms at the Queens Hospital (700 beds) in North London, UK, were sampled for aerobic bacteria after patient discharge, after manual cleaning with a hypochlorous acid-troclosene sodium solution, and after PX-UV disinfection. PX-UV device efficacy on known organisms was tested by exposing inoculated agar plates in a nonpatient care area. Turnaround times for device usage were recorded, and a survey of hospital staff for perceptions of the device was undertaken. After PX-UV disinfection, the bacterial contamination measured in colony forming units (CFU) decreased by 78.4%, a 91% reduction from initial bioburden levels prior to terminal cleaning. PX-UV exposure resulted in a 5-log CFU reduction for multidrug-resistant organisms (MDROs) on spiked plates. The average device turnaround time was 1 hour, with minimal impact on patient throughput. Ward staff were enthusiastic about device deployment, and device operators reported physical comfort in usage. PX-UV use decreased bioburden in patient discharge rooms and on agar plates spiked with MDROs. The implementation of the PX-UV device was well received by hospital cleaning and ward staff, with minimal disruption to patient flow. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. All rights reserved.

Effects of Presowing Pulsed Electromagnetic Treatment of Tomato Seed on Growth, Yield, and Lycopene Content

PubMed Central

Efthimiadou, Aspasia; Katsenios, Nikolaos; Papastylianou, Panayiota; Triantafyllidis, Vassilios; Travlos, Ilias; Bilalis, Dimitrios J.

2014-01-01

The use of magnetic field as a presowing treatment has been adopted by researchers as a new environmental friendly technique. The aim of this study was to determine the effect of magnetic field exposure on tomato seeds covering a range of parameters such as transplanting percentage, plant height, shoot diameter, number of leaves per plant, fresh weight, dry weight, number of flowers, yield, and lycopene content. Pulsed electromagnetic field was used for 0, 5, 10, and 15 minutes as a presowing treatment of tomato seeds in a field experiment for two years. Papimi device (amplitude on the order of 12.5 mT) has been used. The use of pulsed electromagnetic field as a presowing treatment was found to enhance plant growth in tomato plants at certain duration of exposure. Magnetic field treatments and especially the exposure of 10 and 15 minutes gave the best results in all measurements, except plant height and lycopene content. Yield per plant was higher in magnetic field treatments, compared to control. MF-15 treatment yield was 80.93% higher than control treatment. Lycopene content was higher in magnetic field treatments, although values showed no statistically significant differences. PMID:25097875

[Motivation and significance of IARC classification for mobile phone].

PubMed

L'Abbate, N

2011-01-01

In May 2011, the IARC Working Group discussed the possibility that exposure to RF-EMF (radiofrequency electromagnetic fields) have to produce an increased risk for brain tumors and evaluated the available literature on different categories of subjects exposed, including, among others, a Danish cohort study, five case-control studies and the largest multi-center case-control study (INTERPHONE) on the use of mobile phone and brain tumors, including glioma, meningioma and acoustic neuroma. The Working Group also examined a number of studies with objectives related to various mechanisms ofcarcerogenesis. The findings have been reviewed critically and generally assessed as "limited" among users of wireless phones for glioma and acoustic neuroma and "inappropriate" to draw conclusions for other types of tumors. The evidence from occupational and environmental exposures were considered "insufficient" in the same way. Given the limited evidence in humans and in experimental animals, the Working Group has classified a large majority the RF-EMF fields as "possibly carcinogenic to humans" (Group 2B). The Director of IARC has recommended, however,further research in the long-term use of mobile phones and adoption of pragmatic steps to reduce exposure, such as hands-free devices or sms.

Investigation of Basic Mechanisms of Radiation Effects in Carbon-Based Electronic Materials

DTIC Science & Technology

2017-06-01

materials characterization, and carbon nanotube diodes, FET, and PZT-memory test device structures for electrical measurements. Pre - and post -irradiation...definition (Radiation exposure) Task 2) The grantee shall perform testing to include: - Radiation testing . May be multiple types. - Pre and post -rad...technologies for electronic devices. Experiential radiation testing has included exposure to 10 keV X-rays, 4 MeV protons, heavy ions, and Ultra

Evaluation of the Stryker S2 IM Nail Distal Targeting Device for reduction of radiation exposure: a case series study.

PubMed

Anastopoulos, George; Ntagiopoulos, Panagiotis G; Chissas, Dionisios; Loupasis, George; Asimakopoulos, Antonios; Athanaselis, Eustratios; Megas, Panagiotis

2008-10-01

Distal locking is one challenging step during intramedullary nailing of femoral shaft fractures that can lead to an increase of radiation exposure. In the present study, the authors describe a technique for the distal locking of femoral nails, implementing a new targeting device in an attempt to reduce radiation exposure and operational time. Over a 2-year period, 127 consecutive cases of femoral shaft fractures were included in the study. All cases were treated with nailing of femoral shaft fractures with an unslotted reamed antegrade femoral nail and distal locking was performed with the use of a proximally mounted aiming device. Mean duration of the procedure was 63.5 18.1 min while the duration for distal locking was 6.6 +/- 2.6 min. In all successful cases, exposure from intraoperative fluoroscopy was 17.2 +/- 7.4 s for the whole operative procedure, and for distal locking was 2 shots, 1.35 s (range, 0.9-2.2 s) and 1.9 mGy (range, 1.1-2.9 mGy). Five cases (3.9%) were unsuccessful, but overall no intraoperative complications were encountered from the application of this technique. The ability of the device to correspond to the level of nail deformation and to properly identify the distal holes, reduced exposure to radiation compared to other published reports, and should be considered as a valuable tool for distal locking of femoral fractures.

Acute Mountain Sickness at 4500 m is not Altered by Repeated Eight-Hour Exposures to 3200-3550 m Normobaric Hypoxic Equivalent,

DTIC Science & Technology

1987-09-10

subject had his own numbered device, which was disassembled, washed and disinfected ( benzalkonium chloride , 1:1000 v/v) each evening. 4 Subjects...fluctuations throughout the 10-day period after the reduction in altitude equivalent which occurred during day I, either in the group mean values (shown) or...significant reduction in hemoglobin concentration in the control group over the sea level treatment period, with a concomitant, but non-significant

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

Code of Federal Regulations, 2012 CFR

2012-10-01

...: mobile devices. 2.1091 Section 2.1091 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL... workers that can be easily re-located, such as wireless devices associated with a personal computer, are... that operate in the Cellular Radiotelephone Service, the Personal Communications Services, the...

Increased metal concentrations in exhaled breath condensate of industrial welders.

PubMed

Hoffmeyer, Frank; Weiss, Tobias; Lehnert, Martin; Pesch, Beate; Berresheim, Hans; Henry, Jana; Raulf-Heimsoth, Monika; Broding, Horst Christoph; Bünger, Jürgen; Harth, Volker; Brüning, Thomas

2011-01-01

It was the aim of this study to evaluate the effect of different devices on the metal concentration in exhaled breath condensate (EBC) and to prove whether working conditions in different welding companies result in diverse composition of metallic elements. The influence of two collection devices (ECoScreen, ECoScreen2) on detection of metallic elements in EBC was evaluated in 24 control subjects. Properties of ECoScreen and a frequent use can alter EBC metal content due to contamination from metallic components. ECoScreen2 turned out to be favourable for metal assessment. Concentrations of iron, nickel and chromium in EBC sampled with ECoScreen2 were compared between non-exposed controls and industrial welders. Metal concentrations in EBC were higher in 36 welders recruited from three companies. Exposure to welding fumes could be demonstrated predominantly for increased iron concentrations. Concentrations of iron and nickel differed by working conditions, but chromium could not be detected in EBC.

Apparatus for unloading pressurized fluid

DOEpatents

Rehberger, K.M.

1994-01-04

An apparatus is described for unloading fluid, preferably pressurized gas, from containers in a controlled manner that protects the immediate area from exposure to the container contents. The device consists of an unloading housing, which is enclosed within at least one protective structure, for receiving the dispensed contents of the steel container, and a laser light source, located external to the protective structure, for opening the steel container instantaneously. The neck or stem of the fluid container is placed within the sealed interior environment of the unloading housing. The laser light passes through both the protective structure and the unloading housing to instantaneously pierce a small hole within the stem of the container. Both the protective structure and the unloading housing are specially designed to allow laser light passage without compromising the light's energy level. Also, the unloading housing allows controlled flow of the gas once it has been dispensed from the container. The external light source permits remote operation of the unloading device. 2 figures.

Evaluation of an enclosed ultraviolet-C radiation device for decontamination of mobile handheld devices.

PubMed

Mathew, J Itty; Cadnum, Jennifer L; Sankar, Thriveen; Jencson, Annette L; Kundrapu, Sirisha; Donskey, Curtis J

2016-06-01

Mobile handheld devices used in health care settings may become contaminated with health care-associated pathogens. We demonstrated that an enclosed ultraviolet-C radiation device was effective in rapidly reducing methicillin-resistant Staphylococcus aureus, and with longer exposure times, Clostridium difficile spores, on glass slides and reducing contamination on in-use mobile handheld devices. Published by Elsevier Inc.

Control of asthma triggers in indoor air with air cleaners: a modeling analysis.

PubMed

Myatt, Theodore A; Minegishi, Taeko; Allen, Joseph G; Macintosh, David L

2008-08-06

Reducing exposure to environmental agents indoors shown to increase asthma symptoms or lead to asthma exacerbations is an important component of a strategy to manage asthma for individuals. Numerous investigations have demonstrated that portable air cleaning devices can reduce concentrations of asthma triggers in indoor air; however, their benefits for breathing problems have not always been reproducible. The potential exposure benefits of whole house high efficiency in-duct air cleaners for sensitive subpopulations have yet to be evaluated. We used an indoor air quality modeling system (CONTAM) developed by NIST to examine peak and time-integrated concentrations of common asthma triggers present in indoor air over a year as a function of natural ventilation, portable air cleaners, and forced air ventilation equipped with conventional and high efficiency filtration systems. Emission rates for asthma triggers were based on experimental studies published in the scientific literature. Forced air systems with high efficiency filtration were found to provide the best control of asthma triggers: 30-55% lower cat allergen levels, 90-99% lower risk of respiratory infection through the inhalation route of exposure, 90-98% lower environmental tobacco smoke (ETS) levels, and 50-75% lower fungal spore levels than the other ventilation/filtration systems considered. These results indicate that the use of high efficiency in-duct air cleaners provide an effective means of controlling allergen levels not only in a single room, like a portable air cleaner, but the whole house. These findings are useful for evaluating potential benefits of high efficiency in-duct filtration systems for controlling exposure to asthma triggers indoors and for the design of trials of environmental interventions intended to evaluate their utility in practice.

Control of asthma triggers in indoor air with air cleaners: a modeling analysis

PubMed Central

Myatt, Theodore A; Minegishi, Taeko; Allen, Joseph G; MacIntosh, David L

2008-01-01

Background Reducing exposure to environmental agents indoors shown to increase asthma symptoms or lead to asthma exacerbations is an important component of a strategy to manage asthma for individuals. Numerous investigations have demonstrated that portable air cleaning devices can reduce concentrations of asthma triggers in indoor air; however, their benefits for breathing problems have not always been reproducible. The potential exposure benefits of whole house high efficiency in-duct air cleaners for sensitive subpopulations have yet to be evaluated. Methods We used an indoor air quality modeling system (CONTAM) developed by NIST to examine peak and time-integrated concentrations of common asthma triggers present in indoor air over a year as a function of natural ventilation, portable air cleaners, and forced air ventilation equipped with conventional and high efficiency filtration systems. Emission rates for asthma triggers were based on experimental studies published in the scientific literature. Results Forced air systems with high efficiency filtration were found to provide the best control of asthma triggers: 30–55% lower cat allergen levels, 90–99% lower risk of respiratory infection through the inhalation route of exposure, 90–98% lower environmental tobacco smoke (ETS) levels, and 50–75% lower fungal spore levels than the other ventilation/filtration systems considered. These results indicate that the use of high efficiency in-duct air cleaners provide an effective means of controlling allergen levels not only in a single room, like a portable air cleaner, but the whole house. Conclusion These findings are useful for evaluating potential benefits of high efficiency in-duct filtration systems for controlling exposure to asthma triggers indoors and for the design of trials of environmental interventions intended to evaluate their utility in practice. PMID:18684328

Effect of attentional retraining on cognition, craving, and smoking in African American smokers.

PubMed

Robinson, Cendrine D; Muench, Christine; Brede, Emily; Endrighi, Romano; Szeto, Edwin H; Sells, Joanna R; Lammers, John P; Okuyemi, Kolawole S; Waters, Andrew J

2017-08-01

African American cigarette smokers have lower rates of cessation than Whites and live in communities with a higher number of tobacco advertisements. Exposure to smoking cues may promote smoking and undermine cessation. It may be possible to reduce attention to smoking cues ("attentional bias"). In this study, we investigated the effect of attentional retraining (AR) on attentional bias and smoking in African American smokers. Nontreatment- seeking African American smokers (N = 64) were randomly assigned to an AR or control condition. Participants were given a mobile device for 2 weeks and prompted to complete up to 3 AR (or control) trainings per day. Participants completed assessments of attentional bias, craving, and smoking both in the lab and in the field. Participants in the AR and control conditions completed an average of 29.07 AR (SD = 12.48) and 30.61 control training tasks (SD = 13.07), respectively. AR reduced attentional bias assessed in the laboratory, F(1, 126) = 9.20, p = .003, and field, F(1, 374) = 6.18, p = .01. This effect generalized to new stimuli, but not to new tasks. AR did not significantly reduce craving or biological measures of smoking. Smoking assessed on the mobile device declined over days in the AR group, F(1, 26) = 10.95, p = .003, but not in the control group, F(1, 27) = 0.02, p = .89. Two weeks of AR administered on a mobile device reduced attentional bias in African American smokers and had mixed effects on smoking. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Effects of an acute dose of gamma radiation exposure on stem diameter growth, carbon gain, and biomass partitioning in Helianthus annuus

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

Thiede, M.E.

1988-05-25

Nineteen-day-old dwarf sunflower plants (Helianthus annuus, variety NK894) received a variable dose (0-40 Gy) from a cobalt-60 gamma source. A very sensitive stem monitoring device, developed at Battelle's Pacific Northwest Laboratories, Richland, Washington was used to measure real-time changes in stem diameter. Exposure of plants caused a significant reduction in stem growth and root biomass. Doses as low as 5 Gy resulted in a significant increase in leaf density, suggesting that nonreversible morphological growth changes could be induced by very low doses of radiation. Carbohydrate analysis of 40-Gy irradiated plants demonstrated significantly more starch content in leaves and significantly lessmore » starch content in stems 18 days after exposure than did control plants. In contrast, the carbohydrate content in roots of 40-Gy irradiated plants were not significantly different from unirradiated plants 18 days after exposure. These results indicate that radiation either decreased phloem transport or reduced the availability of sugar reducing enzymes in irradiated plants. 44 refs., 12 figs.« less

Total dose bias dependency and ELDRS effects in bipolar linear devices

NASA Technical Reports Server (NTRS)

Yui, C. C.; McClure, S. S.; Rex, B. G.; Lehman, J. M.; Minto, T. D.; Wiedeman, M.

2002-01-01

Total dose tests of several bipolar linear devices show sensitivity to both dose rate and bias during exposure. All devices exhibited Enhanced Low Dose Rate Sensitivity (ELDRS). An accelerated ELDRS test method for three different devices demonstrate results similar to tests at low dose rate. Behavior and critical parameters from these tests are compared and discussed.

Feasibility results of an electromagnetic compatibility test protocol to evaluate medical devices to radio frequency identification exposure

PubMed Central

2014-01-01

Background The use of radio frequency identification (RFID) systems in healthcare is increasing, and concerns for electromagnetic compatibility (EMC) pose one of the biggest obstacles for widespread adoption. Numerous studies have demonstrated that RFID systems can interfere with medical devices; however, the majority of past studies relied on time-consuming and burdensome test schemes based on ad hoc test methods applied to individual RFID systems. Methods This paper presents the results of using an RFID simulator that allows for faster evaluation of RFID-medical device EMC against a library of RFID test signals at various field strengths. Results The results of these tests demonstrate the feasibility and adequacy of simulator testing and can be used to support its incorporation into applicable consensus standards. Conclusions This work can aid the medical device community in better assessing the risks associated with medical device exposure to RFID. PMID:25086451

Feasibility results of an electromagnetic compatibility test protocol to evaluate medical devices to radio frequency identification exposure.

PubMed

Seidman, Seth J; Bekdash, Omar; Guag, Joshua; Mehryar, Maryam; Booth, Paul; Frisch, Paul

2014-08-03

The use of radio frequency identification (RFID) systems in healthcare is increasing, and concerns for electromagnetic compatibility (EMC) pose one of the biggest obstacles for widespread adoption. Numerous studies have demonstrated that RFID systems can interfere with medical devices; however, the majority of past studies relied on time-consuming and burdensome test schemes based on ad hoc test methods applied to individual RFID systems. This paper presents the results of using an RFID simulator that allows for faster evaluation of RFID-medical device EMC against a library of RFID test signals at various field strengths. The results of these tests demonstrate the feasibility and adequacy of simulator testing and can be used to support its incorporation into applicable consensus standards. This work can aid the medical device community in better assessing the risks associated with medical device exposure to RFID.

Understanding the exposure-time effect on speckle contrast measurements for laser displays

NASA Astrophysics Data System (ADS)

Suzuki, Koji; Kubota, Shigeo

2018-02-01

To evaluate the influence of exposure time on speckle noise for laser displays, speckle contrast measurement method was developed observable at a human eye response time using a high-sensitivity camera which has a signal multiplying function. The nonlinearity of camera light sensitivity was calibrated to measure accurate speckle contrasts, and the measuring lower limit noise of speckle contrast was improved by applying spatial-frequency low pass filter to the captured images. Three commercially available laser displays were measured over a wide range of exposure times from tens of milliseconds to several seconds without adjusting the brightness of laser displays. The speckle contrast of raster-scanned mobile projector without any speckle-reduction device was nearly constant over various exposure times. On the contrary to this, in full-frame projection type laser displays equipped with a temporally-averaging speckle-reduction device, some of their speckle contrasts close to the lower limits noise were slightly increased at the shorter exposure time due to the noise. As a result, the exposure-time effect of speckle contrast could not be observed in our measurements, although it is more reasonable to think that the speckle contrasts of laser displays, which are equipped with the temporally-averaging speckle-reduction device, are dependent on the exposure time. This discrepancy may be attributed to the underestimation of temporal averaging factor. We expected that this method is useful for evaluating various laser displays and clarify the relationship between the speckle noise and the exposure time for a further verification of speckle reduction.

A population-based exposure assessment methodology for carbon monoxide: Development of a carbon monoxide passive sampler and occupational dosimeter

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

Apte, Michael G.

Two devices, an occupational carbon monoxide (CO) dosimeter (LOCD), and an indoor air quality (IAQ) passive sampler were developed for use in population-based CO exposure assessment studies. CO exposure is a serious public health problem in the U.S., causing both morbidity and mortality (lifetime mortality risk approximately 10{sup -4}). Sparse data from population-based CO exposure assessments indicate that approximately 10% of the U.S. population is exposed to CO above the national ambient air quality standard. No CO exposure measurement technology is presently available for affordable population-based CO exposure assessment studies. The LOCD and IAQ Passive Sampler were tested in themore » laboratory and field. The palladium-molybdenum based CO sensor was designed into a compact diffusion tube sampler that can be worn. Time-weighted-average (TWA) CO exposure of the device is quantified by a simple spectrophotometric measurement. The LOCD and IAQ Passive Sampler were tested over an exposure range of 40 to 700 ppm-hours and 200 to 4200 ppm-hours, respectively. Both devices were capable of measuring precisely (relative standard deviation <20%), with low bias (<10%). The LOCD was screened for interferences by temperature, humidity, and organic and inorganic gases. Temperature effects were small in the range of 10°C to 30°C. Humidity effects were low between 20% and 90% RH. Ethylene (200 ppm) caused a positive interference and nitric oxide (50 ppm) caused a negative response without the presence of CO but not with CO.« less

Basic-CPR and AIDS: are volunteer life-savers prepared for a storm?

PubMed

Bierens, J J; Berden, H J

1996-10-01

Professional health care workers have access to guidelines, equipment and techniques to reduce the exposure to infectious material in case of resuscitation. The current official content of national courses for volunteer life-savers do not address this issue, as far as we know. Concern about the risks of infection due to resuscitation is increasing in this group. This article describes a rational approach of the problem, that includes data on the infection risk of basic-CPR, and an approach that accepts that the concern can not be controlled by objective data. In such an emotional approach, direct contact has to be minimised by using devices. Requirements for resuscitation devices with a barrier function are listed. Although both approaches will reduce the fear of infection, we advice a rational approach.

Single-Cell RT-PCR in Microfluidic Droplets with Integrated Chemical Lysis.

PubMed

Kim, Samuel C; Clark, Iain C; Shahi, Payam; Abate, Adam R

2018-01-16

Droplet microfluidics can identify and sort cells using digital reverse transcription polymerase chain reaction (RT-PCR) signals from individual cells. However, current methods require multiple microfabricated devices for enzymatic cell lysis and PCR reagent addition, making the process complex and prone to failure. Here, we describe a new approach that integrates all components into a single device. The method enables controlled exposure of isolated single cells to a high pH buffer, which lyses cells and inactivates reaction inhibitors but can be instantly neutralized with RT-PCR buffer. Using our chemical lysis approach, we distinguish individual cells' gene expression with data quality equivalent to more complex two-step workflows. Our system accepts cells and produces droplets ready for amplification, making single-cell droplet RT-PCR faster and more reliable.

Dust remobilization in fusion plasmas under steady state conditions

NASA Astrophysics Data System (ADS)

Tolias, P.; Ratynskaia, S.; De Angeli, M.; De Temmerman, G.; Ripamonti, D.; Riva, G.; Bykov, I.; Shalpegin, A.; Vignitchouk, L.; Brochard, F.; Bystrov, K.; Bardin, S.; Litnovsky, A.

2016-02-01

The first combined experimental and theoretical studies of dust remobilization by plasma forces are reported. The main theoretical aspects of remobilization in fusion devices under steady state conditions are analyzed. In particular, the dominant role of adhesive forces is highlighted and generic remobilization conditions—direct lift-up, sliding, rolling—are formulated. A novel experimental technique is proposed, based on controlled adhesion of dust grains on tungsten samples combined with detailed mapping of the dust deposition profile prior and post plasma exposure. Proof-of-principle experiments in the TEXTOR tokamak and the EXTRAP-T2R reversed-field pinch are presented. The versatile environment of the linear device Pilot-PSI allowed for experiments with different magnetic field topologies and varying plasma conditions that were complemented with camera observations.

Prospective intra-patient evaluation of a shoulder retraction device for radiotherapy in head and neck cancer

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

Newbold, Katie L., E-mail: kate.newbold@rmh.nhs.uk; Bhide, Shreerang; The Institute of Cancer Research, London

Irradiation of tumors in the larynx and pharynx is often technically challenging in patients with a short neck or high shoulders. Shoulder retraction devices can sometimes resolve this problem and allow irradiation via lateral beam directions. This study aimed to measure the proportion of patients who would benefit from such an approach and to quantify the magnitude of the benefit obtained. Twenty patients were studied. Simulator images were obtained before and after intervention. The additional exposure of the cervical spine was measured. Patient comfort and acceptability were assessed with a questionnaire. Improvement of exposure of the cervical spine was observedmore » in 80% of patients. In 20%, there was either no difference or the position was worse. Shoulder retraction exposed a mean of 8.4-10.2 mm more of the cervical spine. Patients in general reported the device as comfortable. The use of a shoulder retraction device produced clinically significant improvements in exposure of the tissues of the cervical spine and neck and should be considered in patients being irradiated for tumors arising in the larynx or hypopharynx.« less

The properties of human body phantoms used in calculations of electromagnetic fields exposure by wireless communication handsets or hand-operated industrial devices.

PubMed

Zradziński, Patryk

2013-06-01

According to international guidelines, the assessment of biophysical effects of exposure to electromagnetic fields (EMF) generated by hand-operated sources needs the evaluation of induced electric field (E(in)) or specific energy absorption rate (SAR) caused by EMF inside a worker's body and is usually done by the numerical simulations with different protocols applied to these two exposure cases. The crucial element of these simulations is the numerical phantom of the human body. Procedures of E(in) and SAR evaluation due to compliance analysis with exposure limits have been defined in Institute of Electrical and Electronics Engineers standards and International Commission on Non-Ionizing Radiation Protection guidelines, but a detailed specification of human body phantoms has not been described. An analysis of the properties of over 30 human body numerical phantoms was performed which has been used in recently published investigations related to the assessment of EMF exposure by various sources. The differences in applicability of these phantoms in the evaluation of E(in) and SAR while operating industrial devices and SAR while using mobile communication handsets are discussed. The whole human body numerical phantom dimensions, posture, spatial resolution and electric contact with the ground constitute the key parameters in modeling the exposure related to industrial devices, while modeling the exposure from mobile communication handsets, which needs only to represent the exposed part of the human body nearest to the handset, mainly depends on spatial resolution of the phantom. The specification and standardization of these parameters of numerical human body phantoms are key requirements to achieve comparable and reliable results from numerical simulations carried out for compliance analysis against exposure limits or within the exposure assessment in EMF-related epidemiological studies.

Vehicle-mounted high-power microwave systems and health risk communication in a deployed environment.

PubMed

Westhoff, John L; Roberts, Brad J; Erickson, Kristin

2013-01-01

Vehicle-mounted high-power microwave systems have been developed to counter the improvised explosive device threat in southwest Asia. Many service members only vaguely comprehend the nature of these devices and the nonionizing radio frequency (RF) radiation they emit. Misconceptions about the health effects of RF radiation have the potential to produce unnecessary anxiety. We report an incident in which concern for exposure to radiation from a high-power microwave device thought to be malfunctioning led to an extensive field investigation, multiple evaluations by clinicians in theater, and subsequent referrals to an Occupational Health clinic upon return from deployment. When acute exposure to RF does occur, the effects are thermally mediated and immediately perceptible--limiting the possibility of injury. Unlike ionizing radiation, RF radiation is not known to cause cancer and the adverse health effects are not cumulative. Medical officers counseling service members concerned about potential RF radiation exposure should apply established principles of risk communication, attend to real and perceived risks, and enlist the assistance of technical experts to properly characterize an exposure when appropriate.

Closed-system drug-transfer devices plus safe handling of hazardous drugs versus safe handling alone for reducing exposure to infusional hazardous drugs in healthcare staff.

PubMed

Gurusamy, Kurinchi Selvan; Best, Lawrence Mj; Tanguay, Cynthia; Lennan, Elaine; Korva, Mika; Bussières, Jean-François

2018-03-27

Occupational exposure to hazardous drugs can decrease fertility and result in miscarriages, stillbirths, and cancers in healthcare staff. Several recommended practices aim to reduce this exposure, including protective clothing, gloves, and biological safety cabinets ('safe handling'). There is significant uncertainty as to whether using closed-system drug-transfer devices (CSTD) in addition to safe handling decreases the contamination and risk of staff exposure to infusional hazardous drugs compared to safe handling alone. To assess the effects of closed-system drug-transfer of infusional hazardous drugs plus safe handling versus safe handling alone for reducing staff exposure to infusional hazardous drugs and risk of staff contamination. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, OSH-UPDATE, CINAHL, Science Citation Index Expanded, economic evaluation databases, the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov to October 2017. We included comparative studies of any study design (irrespective of language, blinding, or publication status) that compared CSTD plus safe handling versus safe handling alone for infusional hazardous drugs. Two review authors independently identified trials and extracted data. We calculated the risk ratio (RR) and mean difference (MD) with 95% confidence intervals (CI) using both fixed-effect and random-effects models. We assessed risk of bias according to the risk of bias in non-randomised studies of interventions (ROBINS-I) tool, used an intracluster correlation coefficient of 0.10, and we assessed the quality of the evidence using GRADE. We included 23 observational cluster studies (358 hospitals) in this review. We did not find any randomised controlled trials or formal economic evaluations. In 21 studies, the people who used the intervention (CSTD plus safe handling) and control (safe handling alone) were pharmacists or pharmacy technicians; in the other two studies, the people who used the intervention and control were nurses, pharmacists, or pharmacy technicians. The CSTD used in the studies were PhaSeal (13 studies), Tevadaptor (1 study), SpikeSwan (1 study), PhaSeal and Tevadaptor (1 study), varied (5 studies), and not stated (2 studies). The studies' descriptions of the control groups were varied. Twenty-one studies provide data on one or more outcomes for this systematic review. All the studies are at serious risk of bias. The quality of evidence is very low for all the outcomes.There is no evidence of differences in the proportion of people with positive urine tests for exposure between the CSTD and control groups for cyclophosphamide alone (RR 0.83, 95% CI 0.46 to 1.52; I² = 12%; 2 studies; 2 hospitals; 20 participants; CSTD: 76.1% versus control: 91.7%); cyclophosphamide or ifosfamide (RR 0.09, 95% CI 0.00 to 2.79; 1 study; 1 hospital; 14 participants; CSTD: 6.4% versus control: 71.4%); and cyclophosphamide, ifosfamide, or gemcitabine (RR not estimable; 1 study; 1 hospital; 36 participants; 0% in both groups).There is no evidence of a difference in the proportion of surface samples contaminated in the pharmacy areas or patient-care areas for any of the drugs except 5-fluorouracil, which was lower in the CSTD group than in the control (RR 0.65, 95% CI 0.43 to 0.97; 3 studies, 106 hospitals, 1008 samples; CSTD: 9% versus control: 13.9%).The amount of cyclophosphamide was lower in pharmacy areas in the CSTD group than in the control group (MD -49.34 pg/cm², 95% CI -84.11 to -14.56, I² = 0%, 7 studies; 282 hospitals, 1793 surface samples). Additionally, one interrupted time-series study (3 hospitals; 342 samples) demonstrated a change in the slope between pre-CSTD and CSTD (3.9439 pg/cm², 95% CI 1.2303 to 6.6576; P = 0.010), but not between CSTD and post-CSTD withdrawal (-1.9331 pg/cm², 95% CI -5.1260 to 1.2598; P = 0.20). There is no evidence of difference in the amount of the other drugs between CSTD and control groups in the pharmacy areas or patient-care areas.None of the studies report on atmospheric contamination, blood tests, or other measures of exposure to infusional hazardous drugs such as urine mutagenicity, chromosomal aberrations, sister chromatid exchanges, or micronuclei induction.None of the studies report short-term health benefits such as reduction in skin rashes, medium-term reproductive health benefits such as fertility and parity, or long-term health benefits related to the development of any type of cancer or adverse events.Five studies (six hospitals) report the potential cost savings through the use of CSTD. The studies used different methods of calculating the costs, and the results were not reported in a format that could be pooled via meta-analysis. There is significant variability between the studies in terms of whether CSTD resulted in cost savings (the point estimates of the average potential cost savings ranged from (2017) USD -642,656 to (2017) USD 221,818). There is currently no evidence to support or refute the routine use of closed-system drug transfer devices in addition to safe handling of infusional hazardous drugs, as there is no evidence of differences in exposure or financial benefits between CSTD plus safe handling versus safe handling alone (very low-quality evidence). None of the studies report health benefits.Well-designed multicentre randomised controlled trials may be feasible depending upon the proportion of people with exposure. The next best study design is interrupted time-series. This design is likely to provide a better estimate than uncontrolled before-after studies or cross-sectional studies. Future studies may involve other alternate ways of reducing exposure in addition to safe handling as one intervention group in a multi-arm parallel design or factorial design trial. Future studies should have designs that decrease the risk of bias and enable measurement of direct health benefits in addition to exposure. Studies using exposure should be tested for a relevant selection of hazardous drugs used in the hospital to provide an estimate of the exposure and health benefits of using CSTD. Steps should be undertaken to ensure that there are no other differences between CSTD and control groups, so that one can obtain a reasonable estimate of the health benefits of using CSTD.

Determinants of exposure to chemical pollutants in wet X-ray film processing in Iran.

PubMed

Kakooei, Hossein; Ardakani, Mehdi B; Sadighi, Alireza

2007-07-15

The aim of the current study was to measure glutaraldehyde, acetic acid and sulfur dioxide and levels inside wet x-ray processing areas in a developing country and comparing data with those in developed countries. Forty-five radiographers from 10 educational hospitals affiliated to the Tehran University of Medical Sciences (TUMS) in Tehran, Iran participated in this descriptive-analytical study. Exposure to glutaraldehyde (a constituent of developer chemistry), acetic acid (a constituent of fixer chemistry) and sulfur dioxide (a byproduct of sulfites present in both developer and fixer solutions) was measured in all participants as well as area exposure. Average full-shift exposure to glutaraldehyde, acetic acid and sulfur dioxide were 0.0018, 2.65 and 1.64 mg m(-1), respectively. The results showed that the TUMS radiographers full-shift exposures are generally lower than the American Conference of Governmental Industrial Hygienists (ACGIH) recommended levels. The concentration of glutaraldehyde collected by area sampling (darkroom) was almost five times (0.0104 mg m(-3)) greater than taken by personal sampling. Exposure to the chemical pollutants in the currents study were generally higher than in developed countries. Identification of these key exposure determinants is useful in targeting exposure evaluation and controls to reduce developer and fixer chemicals exposures in the radiology departments. Employing of a digital imaging system that do not involve wet x-ray processing of photographic film would be a useful device for radiographers protection.

Safety issues associated with the use of nanoparticles in human body.

PubMed

Sufian, Mian Muhammad; Khattak, Jabar Zaman Khan; Yousaf, Shahzad; Rana, Muhammad Suleman

2017-09-01

Nanotechnology has transformed the world by the introduction of a distinctive class of materials and products in a wide array of fields. It has contributed to the production of innovative materials and devices. Having unique advantages and domestic along with industrial applications, however, has raised the issue of safety for consumers, producers and environment. Having a comparative smaller dimension and other exclusive properties, nanoparticles have the ability to harm human body by interacting through various mechanisms. Here, we endeavoured to review and discuss the characteristics of nanoparticles relevant to their toxicity, conceivable exposure routes of nanoparticles to human body like skin contact, inhalation, and ingestion, and the basic approaches which can aid to control human exposures to toxic nanoparticles have been discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Low power arcjet system spacecraft impacts

NASA Technical Reports Server (NTRS)

Pencil, Eric J.; Sarmiento, Charles J.; Lichtin, D. A.; Palchefsky, J. W.; Bogorad, A. L.

1993-01-01

Potential plume contamination of spacecraft surfaces was investigated by positioning spacecraft material samples relative to an arcjet thruster. Samples in the simulated solar array region were exposed to the cold gas arcjet plume for 40 hrs to address concerns about contamination by backstreaming diffusion pump oil. Except for one sample, no significant changes were measured in absorptance and emittance within experimental error. Concerns about surface property degradation due to electrostatic discharges led to the investigation of the discharge phenomenon of charged samples during arcjet ignition. Short duration exposure of charged samples demonstrated that potential differences are consistently and completely eliminated within the first second of exposure to a weakly ionized plume. The spark discharge mechanism was not the discharge phenomenon. The results suggest that the arcjet could act as a charge control device on spacecraft.

Comparison of radiofrequency electromagnetic field exposure levels in different everyday microenvironments in an international context.

PubMed

Sagar, Sanjay; Adem, Seid M; Struchen, Benjamin; Loughran, Sarah P; Brunjes, Michael E; Arangua, Lisa; Dalvie, Mohamed Aqiel; Croft, Rodney J; Jerrett, Michael; Moskowitz, Joel M; Kuo, Tony; Röösli, Martin

2018-05-01

The aim of this study was to quantify RF-EMF exposure applying a tested protocol of RF-EMF exposure measurements using portable devices with a high sampling rate in different microenvironments of Switzerland, Ethiopia, Nepal, South Africa, Australia and the United States of America. We used portable measurement devices for assessing RF-EMF exposure in 94 outdoor microenvironments and 18 public transport vehicles. The measurements were taken either by walking with a backpack with the devices at the height of the head and a distance of 20-30 cm from the body, or driving a car with the devices mounted on its roof, which was 170-180 cm above the ground. The measurements were taken for about 30 min while walking and about 15-20 min while driving in each microenvironment, with a sampling rate of once every 4 s (ExpoM-RF) and 5 s (EME Spy 201). Mean total RF-EMF exposure in various outdoor microenvironments varied between 0.23 V/m (non-central residential area in Switzerland) and 1.85 V/m (university area in Australia), and across modes of public transport between 0.32 V/m (bus in rural area in Switzerland) and 0.86 V/m (Auto rickshaw in urban area in Nepal). For most outdoor areas the major exposure contribution was from mobile phone base stations. Otherwise broadcasting was dominant. Uplink from mobile phone handsets was generally very small, except in Swiss trains and some Swiss buses. This study demonstrates high RF-EMF variability between the 94 selected microenvironments from all over the world. Exposure levels tended to increase with increasing urbanity. In most microenvironments downlink from mobile phone base stations is the most relevant contributor. Copyright © 2018 Elsevier Ltd. All rights reserved.

Nonlinear time dependence of dark current in charge-coupled devices

NASA Astrophysics Data System (ADS)

Dunlap, Justin C.; Bodegom, Erik; Widenhorn, Ralf

2011-03-01

It is generally assumed that charge-coupled device (CCD) imagers produce a linear response of dark current versus exposure time except near saturation. We found a large number of pixels with nonlinear dark current response to exposure time to be present in two scientific CCD imagers. These pixels are found to exhibit distinguishable behavior with other analogous pixels and therefore can be characterized in groupings. Data from two Kodak CCD sensors are presented for exposure times from a few seconds up to two hours. Linear behavior is traditionally taken for granted when carrying out dark current correction and as a result, pixels with nonlinear behavior will be corrected inaccurately.

Noise Exposure Estimates of Urban MP3 Player Users

ERIC Educational Resources Information Center

Levey, Sandra; Levey, Tania; Fligor, Brian J.

2011-01-01

Purpose: To examine the sound level and duration of use of personal listening devices (PLDs) by 189 college students, ages 18-53 years, as they entered a New York City college campus, to determine whether noise exposure from PLDs was in excess of recommended exposure limits and what factors might influence exposure. Method: Free-field equivalent…

DARPA challenge: developing new technologies for brain and spinal injuries

NASA Astrophysics Data System (ADS)

Macedonia, Christian; Zamisch, Monica; Judy, Jack; Ling, Geoffrey

2012-06-01

The repair of traumatic injuries to the central nervous system remains among the most challenging and exciting frontiers in medicine. In both traumatic brain injury and spinal cord injuries, the ultimate goals are to minimize damage and foster recovery. Numerous DARPA initiatives are in progress to meet these goals. The PREventing Violent Explosive Neurologic Trauma program focuses on the characterization of non-penetrating brain injuries resulting from explosive blast, devising predictive models and test platforms, and creating strategies for mitigation and treatment. To this end, animal models of blast induced brain injury are being established, including swine and non-human primates. Assessment of brain injury in blast injured humans will provide invaluable information on brain injury associated motor and cognitive dysfunctions. The Blast Gauge effort provided a device to measure warfighter's blast exposures which will contribute to diagnosing the level of brain injury. The program Cavitation as a Damage Mechanism for Traumatic Brain Injury from Explosive Blast developed mathematical models that predict stresses, strains, and cavitation induced from blast exposures, and is devising mitigation technologies to eliminate injuries resulting from cavitation. The Revolutionizing Prosthetics program is developing an avant-garde prosthetic arm that responds to direct neural control and provides sensory feedback through electrical stimulation. The Reliable Neural-Interface Technology effort will devise technologies to optimally extract information from the nervous system to control next generation prosthetic devices with high fidelity. The emerging knowledge and technologies arising from these DARPA programs will significantly improve the treatment of brain and spinal cord injured patients.

Practices of Unregulated Tanning Facilities in Missouri: Implications for Statewide Legislation

PubMed Central

Biesbroeck, Lauren K.; Lickerman, Stephanie H.; Cornelius, Lynn A.; Jeffe, Donna B.

2013-01-01

BACKGROUND: The incidence of skin cancer has increased in the United States, concomitant with increased UV radiation (UVR) exposure among young adults. We examined whether tanning facilities in Missouri, a state without indoor-tanning regulations, acted in accordance with the Food and Drug Administration’s recommendations and consistently imparted information to potential clients about the known risks of UVR. METHODS: We conducted a statewide telephone survey of randomly selected tanning facilities in Missouri. Each tanning facility was surveyed twice, in the morning (7 am–3 pm) and evening (3–10 pm), on different days, to determine intrasalon consistency of information provided to potential clients at different times. RESULTS: On average, 65% of 243 tanning-facility operators would allow children as young as 10 or 12 years old to use indoor-tanning devices, 80% claimed that indoor tanning would prevent future sunburns, and 43% claimed that there were no risks associated with indoor tanning. Intrasalon inconsistencies involved allowable age of use, and UVR exposure type and duration. Morning tanning-facility employees were more likely to allow consumers to start with maximum exposure times and UV-A–emitting devices (P < .001), whereas evening employees were more likely to allow 10- or 12-year-old children to use indoor-tanning devices (P = .008). CONCLUSIONS: Despite increasing evidence that UVR exposure in indoor-tanning devices is associated with skin cancer, ocular damage, and premature photoaging, tanning facilities in Missouri often misinformed consumers regarding these risks and lack of health benefits and inconsistently provided information about the Food and Drug Administration’s guidelines for tanning devices. PMID:23439910

RF Exposure Analysis for Multiple Wi-Fi Devices In Enclosed Environment

NASA Technical Reports Server (NTRS)

Hwu, Shian U.; Rhodes, Bryan A.; deSilva, B. Kanishka; Sham, Catherine C.; Keiser, James R.

2013-01-01

Wi-Fi devices operated inside a metallic enclosure have been investigation in the recent years. A motivation for this study is to investigate wave propagation inside an enclosed environment such as elevator, car, aircraft, and spacecraft. There are performances and safety concerned that when the RF transmitters are used in the metallic enclosed environments. In this paper, the field distributions inside a confined room were investigated with multiple portable Wi-Fi devices. Computer simulations were performed using the rigorous computational electromagnetics (CEM). The method of moments (MoM) was used to model the mutual coupling among antennas. The geometrical theory of diffraction (GTD) was applied for the multiple reflections off the ground and walls. The prediction of the field distribution inside such environment is useful for the planning and deployment of a wireless radio and sensor system. Factors that affect the field strengths and distributions of radio waves in confined space were analyzed. The results could be used to evaluate the RF exposure safety in confined environment. By comparing the field distributions for various scenarios, it was observed that the Wi-Fi device counts, spacing and relative locations in the room are important factors in such environments. The RF Keep Out Zone (KOZ), where the electric field strengths exceed the permissible RF exposure limit, could be used to assess the RF human exposure compliance. As shown in this study, it s possible to maximize or minimize field intensity in specific area by arranging the Wi-Fi devices as a function of the relative location and spacing in a calculated manner.

Development of the Chemical Exposure Monitor with Indoor Positioning (CEMWIP) for Workplace VOC Surveys

PubMed Central

Brown, KK; Shaw, PB; Mead, KR; Kovein, RJ; Voorhees, RT; Brandes, AR

2016-01-01

The purpose of this project was to research and develop a direct-reading exposure assessment method that combined a real-time location system with a wireless direct-reading personal chemical sensor. The personal chemical sensor was a photoionization device for detecting volatile organic compounds. The combined system was calibrated and tested against the same four standard gas concentrations and calibrated at one standard location and tested at four locations that included the standard locations. Data were wirelessly collected from the chemical sensor every 1.4 seconds, for volatile organic compounds concentration, location, temperature, humidity, and time. Regression analysis of the photo-ionization device voltage response against calibration gases showed the chemical sensor had a limit of detection of 0.2 ppm. The real-time location system was accurate to 13 cm ± 6 cm (standard deviation) in an open area and to 57 cm ± 31 cm in a closed room where the radio frequency has to penetrate drywall-finished walls. The streaming data were collected and graphically displayed as a three-dimensional hazard map for assessment of peak exposure with location. A real-time personal exposure assessment device with indoor positioning was practical and provided new knowledge on direct reading exposure assessment methods. PMID:26786234

Development of the chemical exposure monitor with indoor positioning (CEMWIP) for workplace VOC surveys.

PubMed

Brown, K K; Shaw, P B; Mead, K R; Kovein, R J; Voorhees, R T; Brandes, A R

2016-01-01

The purpose of this article was to research and develop a direct-reading exposure assessment method that combined a real-time location system with a wireless direct-reading personal chemical sensor. The personal chemical sensor was a photoionization device for detecting volatile organic compounds. The combined system was calibrated and tested against the same four standard gas concentrations and calibrated at one standard location and tested at four locations that included the standard locations. Data were wirelessly collected from the chemical sensor every 1.4 sec, for volatile organic compounds concentration, location, temperature, humidity, and time. Regression analysis of the photo-ionization device voltage response against calibration gases showed the chemical sensor had a limit of detection of 0.2 ppm. The real-time location system was accurate to 13 cm ± 6 cm (standard deviation) in an open area and to 57 cm ± 31 cm in a closed room where the radio frequency has to penetrate drywall-finished walls. The streaming data were collected and graphically displayed as a three-dimensional hazard map for assessment of peak exposure with location. A real-time personal exposure assessment device with indoor positioning was practical and provided new knowledge on direct reading exposure assessment methods.

A validation study comparing self-reported travel diaries and objective data obtained from in-vehicle monitoring devices in older drivers with bilateral cataract.

PubMed

Agramunt, Seraina; Meuleners, Lynn; Chow, Kyle Chi; Ng, Jonathon Q; Morlet, Nigel

2017-09-01

Advances in technology have made it possible to examine real-world driving using naturalistic data obtained from in-vehicle monitoring devices. These devices overcome the weaknesses of self-report methods and can provide comprehensive insights into driving exposure, habits and practices of older drivers. The aim of this study is to compare self-reported and objectively measured driving exposure, habits and practices using a travel diary and an in-vehicle driver monitoring device in older drivers with bilateral cataract. A cross-sectional study was undertaken. Forty seven participants aged 58-89 years old (mean=74.1; S.D.=7.73) were recruited from three eye clinics over a one year period. Data collection consisted of a cognitive test, a researcher-administered questionnaire, a travel diary and an in-vehicle monitoring device. Participants' driving exposure and patterns were recorded for one week using in-vehicle monitoring devices. They also completed a travel diary each time they drove a motor vehicle as the driver. Paired t-tests were used to examine differences/agreement between the two instruments under different driving circumstances. The data from the older drivers' travel diaries significantly underestimated the number of overall trips (p<0.001), weekend trips (p=0.002) and trips during peak hour (p=0.004). The travel diaries also significantly overestimated overall driving duration (p<0.001) and weekend driving duration (p=0.003), compared to the data obtained from the in-vehicle monitoring devices. No significant differences were found between instruments for kilometres travelled under any of the driving circumstances. The results of this study found that relying solely on self-reported travel diaries to assess driving outcomes may not be accurate, particularly for estimates of the number of trips made and duration of trips. The clear advantages of using in-vehicle monitoring devices over travel diaries to monitor driving habits and exposure among an older population are evident. Copyright © 2016 Elsevier Ltd. All rights reserved.

Description of the microbial ecology evaluation device, flight equipment, and ground transporter

NASA Technical Reports Server (NTRS)

Chassay, C. E.; Taylor, G. R.

1973-01-01

Exposure of test systems in space required the fabrication of specialized hardware termed a Microbial Ecology Evaluation Device that had individual test chambers and a complex optical filter system. The characteristics of this device and the manner in which it was deployed in space are described.

Risks of carcinogenesis from electromagnetic radiation of mobile telephony devices.

PubMed

Yakymenko, I; Sidorik, E

2010-07-01

Intensive implementation of mobile telephony technology in everyday human life during last two decades has given a possibility for epidemiological estimation of long-term effects of chronic exposure of human organism to low-intensive microwave (MW) radiation. Latest epidemiological data reveal a significant increase in risk of development of some types of tumors in chronic (over 10 years) users of mobile phone. It was detected a significant increase in incidence of brain tumors (glioma, acoustic neuroma, meningioma), parotid gland tumor, seminoma in long-term users of mobile phone, especially in cases of ipsilateral use (case-control odds ratios from 1.3 up to 6.1). Two epidemiological studies have indicated a significant increase of cancer incidence in people living close to the mobile telephony base station as compared with the population from distant area. These data raise a question of adequacy of modern safety limits of electromagnetic radiation (EMR) exposure for humans. For today the limits were based solely on the conception of thermal mechanism of biological effects of RF/MW radiation. Meantime the latest experimental data indicate the significant metabolic changes in living cell under the low-intensive (non-thermal) EMR exposure. Among reproducible biological effects of low-intensive MWs are reactive oxygen species overproduction, heat shock proteins expression, DNA damages, apoptosis. The lack of generally accepted mechanism of biological effects of low-intensive non-ionizing radiation doesn't permit to disregard the obvious epidemiological and experimental data of its biological activity. Practical steps must be done for reasonable limitation of excessive EMR exposure, along with the implementation of new safety limits of mobile telephony devices radiation, and new technological decisions, which would take out the source of radiation from human brain.

Tanning beds, sunlamps, and risk of cutaneous malignant melanoma.

PubMed

Gallagher, Richard P; Spinelli, John J; Lee, Tim K

2005-03-01

A number of studies have been conducted evaluating the risk of cutaneous malignant melanoma after exposure to sunlamps and/or sunbeds. The proportion of subjects in the individual studies who have reported exposure has, in general, been modest, and the resulting risk estimates for melanoma have been unstable with wide 95% confidence intervals (95% CI). The inconclusive results seen in individual studies have resulted in confusion as to the carcinogenicity of these devices. We conducted a systematic review and meta-analysis of these studies. A review of the literature from Jan 1, 1984 to April 2004 using MEDLINE identified 12 case-control studies and 1 cohort study which quantitatively evaluated the use of sunlamps and/or sunbeds and subsequent melanoma. After applying exclusion/inclusion criteria, 9 case-control and 1 cohort study provided data for the analysis. Summary odds ratios (OR) and 95% CIs for sunlamp/sunbed use and subsequent melanoma were calculated using a random-effect model. Ten studies provided data for assessment of melanoma risk among subjects who reported "ever" being exposed compared with those "never" exposed. A positive association was found between exposure and risk (summary OR, 1.25; 95% CI, 1.05-1.49). Significant heterogeneity between studies was present. Evaluation of the metrics "first exposure as a young adult" (5 studies) and "longest duration or highest frequency of exposure" (6 studies) also yielded significantly elevated risk estimates (summary OR, 1.69; 95% CI, 1.32-2.18, and 1.61; 95% CI, 1.21-2.12, respectively, with no heterogeneity in either analysis). Results indicate a significantly increased risk of cutaneous melanoma subsequent to sunbed/sunlamp exposure.

Cumulative effects of heat exposure and storage conditions of Oxytocin-in-Uniject in rural Ghana: implications for scale up

PubMed Central

Mullany, Luke C; Newton, Sam; Afari-Asiedu, Samuel; Adiibokah, Edward; Agyemang, Charlotte T; Cofie, Patience; Brooke, Steve; Owusu-Agyei, Seth; Stanton, Cynthia K

2014-01-01

ABSTRACT Objective: Postpartum hemorrhage can be reduced substantially in home deliveries attended by community-based workers by using Oxytocin-in-Uniject (OIU) devices affixed with temperature-time indicators. We characterized the distribution of time to discard of these devices when stored under normal field conditions in Ghana. Methods: Two drug storage simulation studies were conducted in rural Ghana in 2011 and 2012. Devices were transported under refrigeration from manufacture (Argentina) to storage at the study site. Twenty-three field workers each stored at home (unrefrigerated) 25 OIU devices and monitored them daily to record: (1) time to transition from usable to unusable, and (2) continuous digital ambient temperature to determine heat exposure over the simulation period. Time to discard was estimated and compared with mean kinetic temperature exposure of the devices during the shipment and storage phases and with characteristics of the storage locations using Weibull regression models. We used the time to discard distributions in a Monte Carlo simulation to estimate wastage rates in a hypothetical program setting. Results: Time for shipment and transfer to long-term refrigerated storage and mean kinetic temperature during the shipment phase was 8.6 days/10.3°C and 13.4 days/12.1°C, for the first and second simulation studies, respectively. Median (range) time to discard when stored under field conditions (unrefrigerated) was 43 (6 to 59) days and 33 (14 to 50) days, respectively. Mean time to discard was 10.0 days shorter in the second simulation, during which mean kinetic temperature exposure was 3.9°C higher. Simulating a monthly distribution system and assuming typical usage, predicted wastage of product was less than 10%. Conclusion: The time to discard of devices was highly sensitive to small changes in temperature exposure. Under field conditions typical in rural Ghana, OIU packages will have a half-life of approximately 30 to 40 days based on the temperature monitor used during the study. Program managers will need to carefully consider variations in both ambient temperature and rate of use to allocate the appropriate supply level that will maximize coverage and minimize stock loss. PMID:25276588

Cumulative effects of heat exposure and storage conditions of Oxytocin-in-Uniject in rural Ghana: implications for scale up.

PubMed

Mullany, Luke C; Newton, Sam; Afari-Asiedu, Samuel; Adiibokah, Edward; Agyemang, Charlotte T; Cofie, Patience; Brooke, Steve; Owusu-Agyei, Seth; Stanton, Cynthia K

2014-08-01

Postpartum hemorrhage can be reduced substantially in home deliveries attended by community-based workers by using Oxytocin-in-Uniject (OIU) devices affixed with temperature-time indicators. We characterized the distribution of time to discard of these devices when stored under normal field conditions in Ghana. Two drug storage simulation studies were conducted in rural Ghana in 2011 and 2012. Devices were transported under refrigeration from manufacture (Argentina) to storage at the study site. Twenty-three field workers each stored at home (unrefrigerated) 25 OIU devices and monitored them daily to record: (1) time to transition from usable to unusable, and (2) continuous digital ambient temperature to determine heat exposure over the simulation period. Time to discard was estimated and compared with mean kinetic temperature exposure of the devices during the shipment and storage phases and with characteristics of the storage locations using Weibull regression models. We used the time to discard distributions in a Monte Carlo simulation to estimate wastage rates in a hypothetical program setting. Time for shipment and transfer to long-term refrigerated storage and mean kinetic temperature during the shipment phase was 8.6 days/10.3°C and 13.4 days/12.1°C, for the first and second simulation studies, respectively. Median (range) time to discard when stored under field conditions (unrefrigerated) was 43 (6 to 59) days and 33 (14 to 50) days, respectively. Mean time to discard was 10.0 days shorter in the second simulation, during which mean kinetic temperature exposure was 3.9°C higher. Simulating a monthly distribution system and assuming typical usage, predicted wastage of product was less than 10%. The time to discard of devices was highly sensitive to small changes in temperature exposure. Under field conditions typical in rural Ghana, OIU packages will have a half-life of approximately 30 to 40 days based on the temperature monitor used during the study. Program managers will need to carefully consider variations in both ambient temperature and rate of use to allocate the appropriate supply level that will maximize coverage and minimize stock loss.

Rare earth elements in human and animal health: State of art and research priorities

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

Pagano, Giovanni, E-mail: gbpagano@tin.it; Aliberti, Francesco; Guida, Marco

Background: A number of applications have been developed using rare earth elements (REE), implying several human exposures and raising unsolved questions as to REE-associated health effects. Methods: A MedLine survey was retrieved from early reports (1980s) up to June 2015, focused on human and animal exposures to REE. Literature from animal models was selected focusing on REE-associated health effects. Results: Some REE occupational exposures, in jobs such as glass polishers, photoengravers and movie projectionists showed a few case reports on health effects affecting the respiratory system. No case-control or cohort studies of occupational REE exposures were retrieved. Environmental exposures havemore » been biomonitored in populations residing in REE mining areas, showing REE accumulation. The case for a iatrogenic REE exposure was raised by the use of gadolinium-based contrast agents for nuclear magnetic resonance. Animal toxicity studies have shown REE toxicity, affecting a number of endpoints in liver, lungs and blood. On the other hand, the use of REE as feed additives in livestock is referred as a safe and promising device in zootechnical activities, possibly suggesting a hormetic effect both known for REE and for other xenobiotics. Thus, investigations on long-term exposures and observations are warranted. Conclusion: The state of art provides a limited definition of the health effects in occupationally or environmentally REE-exposed human populations. Research priorities should be addressed to case-control or cohort studies of REE-exposed humans and to life-long animal experiments. - Highlights: • An extensive number of activities have been developed utilizing rare earth elements (REE). • The literature of REE-associated health effects in humans, and on animal studies is reviewed. • The main literature gaps are discussed, in epidemiological and in animal studies. • Prospects studies are suggested, aimed at evaluating long-term effects of REE exposures. • The relevance of REE-related hormesis, speciation and acidic pollution are discussed.« less

Simulation of irradiation exposure of electronic devices due to heavy ion therapy with Monte Carlo Code MCNP6

NASA Astrophysics Data System (ADS)

Lapins, Janis; Guilliard, Nicole; Bernnat, Wolfgang; Buck, Arnulf

2017-09-01

During heavy ion irradiation therapy the patient has to be located exactly at the right position to make sure that the Bragg peak occurs in the tumour. The patient has to be moved in the range of millimetres to scan the ill tissue. For that reason a special table was developed which allows exact positioning. The electronic control can be located outside the surgery. But that has some disadvantage for the construction. To keep the system compact it would be much more comfortable to put the electronic control inside the surgery. As a lot of high energetic secondary particles are produced during the therapy causing a high dose in the room it is important to find positions with low dose rates. Therefore, investigations are needed where the electronic devices should be located to obtain a minimum of radiation, help to prevent the failure of sensitive devices. The dose rate was calculated for carbon ions with different initial energy and protons over the entire therapy room with Monte Carlo particle tracking using MCNP6. The types of secondary particles were identified and the dose rate for a thin silicon layer and an electronic mixture material was determined. In addition, the shielding effect of several selected material layers was calculated using MCNP6.

KENNEDY SPACE CENTER, FLA. - On a tour of the KSC Beach Corrosion Test Site, Testbed Manager Louis MacDowell (right) explains to Center Director Jim Kennedy about the test blocks being used to test a newly developed coating to protect steel inside concrete. Between MacDowell and Kennedy are Dr. Paul Hintze and Lead Scientist Dr. Luz Marina Calle. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

NASA Image and Video Library

2003-08-21

KENNEDY SPACE CENTER, FLA. - On a tour of the KSC Beach Corrosion Test Site, Testbed Manager Louis MacDowell (right) explains to Center Director Jim Kennedy about the test blocks being used to test a newly developed coating to protect steel inside concrete. Between MacDowell and Kennedy are Dr. Paul Hintze and Lead Scientist Dr. Luz Marina Calle. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

Effect of Ginseng on Calretinin Expression in Mouse Hippocampus Following Exposure to 835 MHz Radiofrequency

PubMed Central

Aryal, Bijay; Maskey, Dhiraj; Kim, Myeung-Ju; Yang, Jae-Won; Kim, Hyung-Gun

2011-01-01

Exponential rise in the use of mobile communication devices has generated health concerns due to radiofrequency (RF) exposure due to its close proximity to the head. Calcium binding proteins like calretinin regulate the levels of calcium (Ca2+) which plays an important role in biological systems. Ginseng is known for maintaining equilibrium in the human body and may play a beneficial radioprotectant role against electromagnetic field (EMF) exposure. In the present study, we evaluated the radioprotective effects of red ginseng (RG) extract in a mouse model. Calretinin (CR) expression was measured using a free-floating immunohistochemical method in the hippocampus of mice after 835 MHz EMF exposure for 5 h/d for 5 d at specific absorption rate=1.6 W/kg for the different experimental groups. The control animals were treated with NaCl while the experimental animals received 10 mg/kg ginseng, or 30 mg/kg; EMF exposed mice were also treated with NaCl, 10 mg/kg ginseng (E10), or 30 mg/kg (E30). Decreases in CR immunoreactivity (IR) along with loss of CA1 and CA3 interneurons and infragranular cells were observed in the ENaCl group while such losses were not observed in the E10 and E30 groups. CR IR significantly increased in the RG-treated group compared to control and EMF-exposed groups treated with NaCl. The study demonstrates that RG extract can serve as a radioprotective agent that maintains Ca2+ homeostasis and prevents neuronal loss in the brain hippocampal region caused by RF exposure. PMID:23717055

Spatial and temporal variability of personal environmental exposure to radio frequency electromagnetic fields in children in Europe.

PubMed

Birks, Laura Ellen; Struchen, Benjamin; Eeftens, Marloes; van Wel, Luuk; Huss, Anke; Gajšek, Peter; Kheifets, Leeka; Gallastegi, Mara; Dalmau-Bueno, Albert; Estarlich, Marisa; Fernandez, Mariana F; Meder, Inger Kristine; Ferrero, Amparo; Jiménez-Zabala, Ana; Torrent, Maties; Vrijkotte, Tanja G M; Cardis, Elisabeth; Olsen, Jørn; Valič, Blaž; Vermeulen, Roel; Vrijheid, Martine; Röösli, Martin; Guxens, Mònica

2018-08-01

Exposure to radiofrequency electromagnetic fields (RF-EMF) has rapidly increased and little is known about exposure levels in children. This study describes personal RF-EMF environmental exposure levels from handheld devices and fixed site transmitters in European children, the determinants of this, and the day-to-day and year-to-year repeatability of these exposure levels. Personal environmental RF-EMF exposure (μW/m 2 , power flux density) was measured in 529 children (ages 8-18 years) in Denmark, the Netherlands, Slovenia, Switzerland, and Spain using personal portable exposure meters for a period of up to three days between 2014 and 2016, and repeated in a subsample of 28 children one year later. The meters captured 16 frequency bands every 4 s and incorporated a GPS. Activity diaries and questionnaires were used to collect children's location, use of handheld devices, and presence of indoor RF-EMF sources. Six general frequency bands were defined: total, digital enhanced cordless telecommunications (DECT), television and radio antennas (broadcast), mobile phones (uplink), mobile phone base stations (downlink), and Wireless Fidelity (WiFi). We used adjusted mixed effects models with region random effects to estimate associations of handheld device use habits and indoor RF-EMF sources with personal RF-EMF exposure. Day-to-day and year-to-year repeatability of personal RF-EMF exposure were calculated through intraclass correlations (ICC). Median total personal RF-EMF exposure was 75.5 μW/m 2 . Downlink was the largest contributor to total exposure (median: 27.2 μW/m 2 ) followed by broadcast (9.9 μW/m 2 ). Exposure from uplink (4.7 μW/m 2 ) was lower. WiFi and DECT contributed very little to exposure levels. Exposure was higher during day (94.2 μW/m 2 ) than night (23.0 μW/m 2 ), and slightly higher during weekends than weekdays, although varying across regions. Median exposures were highest while children were outside (157.0 μW/m 2 ) or traveling (171.3 μW/m 2 ), and much lower at home (33.0 μW/m 2 ) or in school (35.1 μW/m 2 ). Children living in urban environments had higher exposure than children in rural environments. Older children and users of mobile phones had higher uplink exposure but not total exposure, compared to younger children and those that did not use mobile phones. Day-to-day repeatability was moderate to high for most of the general frequency bands (ICCs between 0.43 and 0.85), as well as for total, broadcast, and downlink for the year-to-year repeatability (ICCs between 0.49 and 0.80) in a small subsample. The largest contributors to total personal environmental RF-EMF exposure were downlink and broadcast, and these exposures showed high repeatability. Urbanicity was the most important determinant of total exposure and mobile phone use was the most important determinant of uplink exposure. It is important to continue evaluating RF-EMF exposure in children as device use habits, exposure levels, and main contributing sources may change. Copyright © 2018 Elsevier Ltd. All rights reserved.

Accessible virtual reality therapy using portable media devices.

PubMed

Bruck, Susan; Watters, Paul A

2010-01-01

Simulated immersive environments displayed on large screens are a valuable therapeutic asset in the treatment of a range of psychological disorders. Permanent environments are expensive to build and maintain, require specialized clinician training and technical support and often have limited accessibility for clients. Ideally, virtual reality exposure therapy (VRET) could be accessible to the broader community if we could use inexpensive hardware with specifically designed software. This study tested whether watching a handheld non-immersive media device causes nausea and other cybersickness responses. Using a repeated measure design we found that nausea, general discomfort, eyestrain, blurred vision and an increase in salivation significantly increased in response to handheld non-immersive media device exposure.

Gamma radiation in ceramic capacitors: a study for space missions

NASA Astrophysics Data System (ADS)

dos Santos Ferreira, Eduardo; Sarango Souza, Juliana

2017-10-01

We studied the real time effects of the gamma radiation in ceramic capacitors, in order to evaluate the effects of cosmic radiation on these devices. Space missions have electronic circuits with various types of devices, many studies have been done on semiconductor devices exposed to gamma radiation, but almost no studies for passive components, in particular ceramic capacitors. Commercially sold ceramic capacitors were exposed to gamma radiation, and the capacitance was measured before and after exposure. The results clearly show that the capacitance decreases with exposure to gamma radiation. We confirmed this observation in a real time capacitance measurement, obtained using a data logging system developed by us using the open source Arduino platform.

Development of an attract-and-infect system to control Rhynchophorus ferrugineus with the entomopathogenic fungus Beauveria bassiana.

PubMed

Dembilio, Óscar; Moya, Pilar; Vacas, Sandra; Ortega-García, Lola; Quesada-Moraga, Enrique; Jaques, Josep A; Navarro-Llopis, Vicente

2018-02-09

A new Beauveria bassiana-based attract and infect device (AID) to control Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae) was developed. The virulence and persistence of the fungal formulation used in the AID were evaluated in the laboratory. Semi-field and field trials were carried out to validate the results and establish the potential of this device as a control tool. In laboratory conditions, a 50% lethal time (LT 50 ) of 4.33 days was obtained when adults (7-10 days old) were exposed to the inoculation tunnel (IT) containing 1 × 10 10 conidia g -1 in an oil-based fungal formulation. This formulation maintained conidium viability at 50% for up to 2 months. Moreover, when adults were exposed to 2.5-month field-aged ITs, mortality still reached 50% 40 days after exposure. In addition, no differences were observed between ITs aged in early spring and those aged in summer, suggesting that the fungal formulation is not strongly affected by environmental factors in Mediterranean basin conditions. Semi-field assays showed that the device allowed an easy transit of weevils through the IT, which were effectively attracted and infected. Using the AIDs in 4-ha plot field trials, a reduction of >50% in the percentage of infested sentinel palms was obtained. Based on the results obtained in terms of the efficacy and persistence of this new AID in the field and its potential in reducing R. ferrugineus populations and palm infestation, this device could become a key tool for the management of R. ferrugineus. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Feasibility of a portable X-ray fluorescence device for bone lead measurements of condor bones.

PubMed

Specht, Aaron J; Parish, Chris N; Wallens, Emma K; Watson, Rick T; Nie, Linda H; Weisskopf, Marc G

2018-02-15

Lead based ammunition is a primary source of lead exposure, especially for scavenging wildlife. Lead poisoning remains the leading cause of diagnosed death for the critically endangered California condors, which are annually monitored via blood tests for lead exposure. The results of these tests are helpful in determining recent exposure in condors and in defining the potential for exposure to other species including humans. Since condors are victim to acute and chronic lead exposure, being able to measure both would lend valuable information on the rates of exposure and accumulation through time. A commercial portable X-ray fluorescence (XRF) device has been optimized to measure bone lead in vivo in humans, but this device could also be valuable for field measurements of bone lead in avian species. In this study, we performed measurements of bone Pb in excised, bare condor bones using inductively coupled plasma mass spectrometry (ICP-MS), a cadmium 109 (Cd-109) K-shell X-ray fluorescence (KXRF) system, and a portable XRF system. Both KXRF and portable XRF bone Pb measurement techniques demonstrated good correlations with ICP-MS results (r=0.93 and r=0.92 respectively), even with increasing skin thickness (r=0.86 between ICP-MS and portable XRF at 1.54mm of soft tissue). In conclusion, our results suggest that a portable XRF could be a useful option for measurement of bone Pb in avian species in the field. Copyright © 2017 Elsevier B.V. All rights reserved.

a Thermally Desorbable Miniature Passive Dosimeter for Organic Vapors

NASA Astrophysics Data System (ADS)

Gonzalez, Jesus Antonio

A thermally desorbable miniature passive dosimeter (MPD) for organic vapors has been developed in conformity with theoretical and practical aspects of passive dosimeter design. The device was optimized for low sample loadings resulting from short-term and/or low concentration level exposure. This was accomplished by the use of thermal desorption rather than solvent elution, which provided the GC method with significantly higher sensitivity. Laboratory evaluation of this device for factors critical to the performance of passive dosimeters using benzene as the test vapor included: desorption efficiency (97.2%), capacity (1400 ppm-min), sensitivity (7ng/sample or 0.06 ppmv for 15 minutes sampling) accuracy and precision, concentration level, environmental conditions (i.e., air face velocity, relative humidity) and sample stability during short (15 minutes) and long periods of time (15 days). This device has demonstrated that its overall accuracy meets NIOSH and OSHA requirements for a sampling and analytical method for the exposure concentration range of 0.1 to 50 ppm (v/v) and 15 minutes exposures. It was demonstrated that the MPD operates in accordance with theoretically predicted performance and should be adequate for short-term and/or low concentration exposure monitoring of organic vapors in the workplace. In addition a dynamic vapor exposure evaluation system for passive dosimeters have been validated using benzene as the test vapor. The system is capable of generating well defined short-square wave concentration profiles suitable for the evaluation of passive dosimeters for ceiling exposure monitoring.

100-nm gate lithography for double-gate transistors

NASA Astrophysics Data System (ADS)

Krasnoperova, Azalia A.; Zhang, Ying; Babich, Inna V.; Treichler, John; Yoon, Jung H.; Guarini, Kathryn; Solomon, Paul M.

2001-09-01

The double gate field effect transistor (FET) is an exploratory device that promises certain performance advantages compared to traditional CMOS FETs. It can be scaled down further than the traditional devices because of the greater electrostatic control by the gates on the channel (about twice as short a channel length for the same gate oxide thickness), has steeper sub-threshold slope and about double the current for the same width. This paper presents lithographic results for double gate FET's developed at IBM's T. J. Watson Research Center. The device is built on bonded wafers with top and bottom gates self-aligned to each other. The channel is sandwiched between the top and bottom polysilicon gates and the gate length is defined using DUV lithography. An alternating phase shift mask was used to pattern gates with critical dimensions of 75 nm, 100 nm and 125 nm in photoresist. 50 nm gates in photoresist have also been patterned by 20% over-exposure of nominal 100 nm lines. No trim mask was needed because of a specific way the device was laid out. UV110 photoresist from Shipley on AR-3 antireflective layer were used. Process windows, developed and etched patterns are presented.

Evaluation of home allergen sampling devices.

PubMed

Sercombe, J K; Liu-Brennan, D; Garcia, M L; Tovey, E R

2005-04-01

Simple, inexpensive methods of sampling from allergen reservoirs are necessary for large-scale studies or low-cost householder-operated allergen measurement. We tested two commercial devices: the Indoor Biotechnologies Mitest Dust Collector and the Drager Bio-Check Allergen Control; two devices of our own design: the Electrostatic Cloth Sampler (ECS) and the Press Tape Sampler (PTS); and a Vacuum Sampler as used in many allergen studies (our Reference Method). Devices were used to collect dust mite allergen samples from 16 domestic carpets. Results were examined for correlations between the sampling methods. With mite allergen concentration expressed as microg/g, the Mitest, the ECS and the PTS correlated with the Reference Method but not with each other. When mite allergen concentration was expressed as microg/m2 the Mitest and the ECS correlated with the Reference Method but the PTS did not. In the high allergen conditions of this study, the Drager Bio-Check did not relate to any methods. The Mitest Dust Collector, the ECS and the PTS show performance consistent with the Reference Method. Many techniques can be used to collect dust mite allergen samples. More investigation is needed to prove any method as superior for estimating allergen exposure.

Electrothermal debonding of ceramic brackets. An in vitro study.

PubMed

Brouns, E M; Schopf, P M; Kocjancic, B

1993-04-01

Two different kinds of devices for electrothermal debonding of ceramic brackets are evaluated. Thirty human premolars were bonded with two types of ceramic brackets. Both devices were tested for electrothermal removal of the two bracket types. The pulpal wall temperature increase during electrothermal debonding was recorded in vitro under various circumstances. After debonding, the fracture site was located. The data were compared to the temperature rise after simulated exposure of the teeth to warm beverages. Irreversible pulp damage due to electrothermal debonding of ceramic brackets with both instruments is not to be expected because the obtained results stayed below established primate threshold temperatures and significantly below that of the stimulated control groups. A significant difference was noted when air cooling was initiated during electrothermal debonding. Fracture site location was significantly different in the two ceramic bracket types after electrothermal debonding.

The thermal stability of sodium beta'-Alumina solid electrolyte ceramic in AMTEC cells

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

Williams, Roger M.; Ryan, Margaret A.; Homer, Margie L.

1999-01-22

A critical component of alkali metal thermal-to electric converter (AMTEC) devices for long duration space missions is the beta'-alumina solid electrolyte ceramic (BASE), for which there exists no substitute. The temperature and environmental conditions under which BASE remains stable control operational parameters of AMTEC devices. We have used mass loss experiments in vacuum to 1573K to characterize the kinetics of BASE decomposition, and conductivity and exchange current measurements in sodium vapor filled exposure cells to 1223K to investigate changes in the BASE which affect its ionic conductivity. There is no clear evidence of direct thermal decomposition of BASE below 1273K,more » although limited soda loss may occur. Reactive metals such as Mn or Cr can react with BASE at temperatures at least as low as 1223K.« less

Noise Pollution Control System in the Hospital Environment

NASA Astrophysics Data System (ADS)

Figueroa Gallo, LM; Olivera, JM

2016-04-01

Problems related to environmental noise are not a new subject, but they became a major issue to solve because of the increasing, in complexity and intensity, of human activities due technological advances. Numerous international studies had dealt with the exposure of critical patients to noisy environment such as the Neonatal Intensive Care Units; their results show that there are difficulties in the organization in the developing brain, it can damage the delicate auditory structures and can cause biorhythm disorders, specially in preterm infants. The objective of this paper is to present the development and implementation of a control system that includes technical-management-training aspects to regulate the levels of specific noise sources in the neonatal hospitalization environment. For this purpose, there were applied different tools like: observations, surveys, procedures, an electronic control device and a training program for a Neonatal Service Unit. As a result, all noise sources were identified -some of them are eliminable-; all the service stable staff categories participated voluntarily; environmental noise measurements yielded values between 62.5 and 64.6 dBA and maximum were between 86.1 and 89.7 dBA; it was designed and installed a noise control device and the staff is being trained in noise reduction best practices.

Direct hip joint distraction during acetabular fracture surgery using the AO universal manipulator.

PubMed

Calafi, L Afshin; Routt, M L Chip

2010-02-01

Certain acetabular fractures may necessitate distraction of the hip joint for removal of intra-articular debris and assessment of reduction. Distraction can be accomplished by manual traction, using a traction table or an AO universal manipulator (UM). The UM is a relatively simple and an inexpensive device that can provide focal distraction in a controlled manner without the risks associated with the use of a traction table. We describe a technique using the UM for hip joint distraction during acetabular fracture surgery through a Kocher-Langenbeck surgical exposure.

Cryopreservation of human insulin expressing cells macro-encapsulated in a durable therapeutic immunoisolating device theracyte.

PubMed

Yakhnenko, Ilya; Wong, Wallace K; Katkov, Igor I; Itkin-Ansari, Pamela

2012-01-01

Encapsulating insulin producing cells (INPCs) in an immunoisolation device have been shown to cure diabetes in rodents without the need for immunosuppression. However, micro-encapsulation in semi-solid gels raises longevity and safety concerns for future use of stem cell derived INPCs. We have focused on a durable and retrievable macro-encapsulation (> 10(6) cells) device (TheraCyte). Cryopreservation (CP) of cells preloaded into the device is highly desirable but may require prolonged exposure to cryoprotectants during loading and post-thaw manipulations. Here, we are reporting survival and function of a human islet cell line frozen as single cells or as islet-like cell clusters. The non-clusterized cells exhibited high cryosurvival after prolonged pre-freeze or post-thaw exposure to 10 percent DMSO. However, both clusterization and especially loading INPCs into the device reduced viable yield even without CP. The survived cryopreserved macro-encapsulated INPCs remained fully functional suggesting that CP of macro-encapsulated cells is a promising tool for cell based therapies.

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

Choi, Hyun-Sik; Jeon, Sanghun, E-mail: jeonsh@korea.ac.kr

Upon light exposure, an indium-zinc-oxide (IZO) thin-film transistor (TFT) presents higher photoconductivity by several orders of magnitude at the negative gate bias region. Among various device geometrical factors, scaling down the channel length of the photo-transistor results in an anomalous increase in photoconductivity. To probe the origin of this high photoconductivity in short-channel device, we measured transient current, current–voltage, and capacitance–voltage characteristics of IZO–TFTs with various channel lengths and widths before and after illumination. Under the illumination, the equilibrium potential region which lies far from front interface exists only in short-channel devices, forming the un-depleted conducting back channel. This regionmore » plays an important role in carrier transport under the illumination, leading to high photoconductivity in short-channel devices. Photon exposure coupled with gate-modulated band bending for short-channel devices leads to the accumulation of V{sub o}{sup ++} at the front channel and screening negative gate bias, thereby generating high current flow in the un-depleted back-channel region.« less

Second Generation Electronic Nicotine Delivery System Vape Pen Exposure Generalizes as a Smoking Cue.

PubMed

King, Andrea C; Smith, Lia J; McNamara, Patrick J; Cao, Dingcai

2018-01-05

Second generation electronic nicotine delivery systems (ENDS; also known as e-cigarettes, vaporizers or vape pens) are designed for a customized nicotine delivery experience and have less resemblance to regular cigarettes than first generation "cigalikes." The present study examined whether they generalize as a conditioned cue and evoke smoking urges or behavior in persons exposed to their use. Data were analyzed in N = 108 young adult smokers (≥5 cigarettes per week) randomized to either a traditional combustible cigarette smoking cue or a second generation ENDS vaping cue in a controlled laboratory setting. Cigarette and e-cigarette urge and desire were assessed pre- and post-cue exposure. Smoking behavior was also explored in a subsample undergoing a smoking latency phase after cue exposure (N = 26). The ENDS vape pen cue evoked both urge and desire for a regular cigarette to a similar extent as that produced by the combustible cigarette cue. Both cues produced similar time to initiate smoking during the smoking latency phase. The ENDS vape pen cue elicited smoking urge and desire regardless of ENDS use history, that is, across ENDS naїve, lifetime or current users. Inclusion of past ENDS or cigarette use as covariates did not significantly alter the results. These findings demonstrate that observation of vape pen ENDS use generalizes as a conditioned cue to produce smoking urge, desire, and behavior in young adult smokers. As the popularity of these devices may eventually overtake those of first generation ENDS cigalikes, exposure effects will be of increasing importance. This study shows that passive exposure to a second generation ENDS vape pen cue evoked smoking urge, desire, and behavior across a range of daily and non-daily young adult smokers. Smoking urge and desire increases after vape pen exposure were similar to those produced by exposure to a first generation ENDS cigalike and a combustible cigarette, a known potent cue. Given the increasing popularity of ENDS tank system products, passive exposures to these devices will no doubt increase, and may contribute to tobacco use in young adult smokers. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A pilot study on the reproductive risks of maternal exposure to magnetic fields from electronic article surveillance systems.

PubMed

Khan, Muhammad Waseem; Roivainen, Päivi; Herrala, Mikko; Tiikkaja, Maria; Sallmén, Markku; Hietanen, Maila; Juutilainen, Jukka

2018-02-26

We investigated the feasibility of a large-scale epidemiological study on reproductive effects of intermediate frequency (IF) magnetic field (MF) exposure among cashiers working near electronic article surveillance (EAS) systems. The study cohort included 4157 women who had worked as cashiers in supermarkets with EAS devices (considered as exposed) or grocery stores without EAS devices (considered as unexposed) between 2008 and 2015. 536 births and 38 miscarriages occurred among these women during the study period, based on information from nationwide health registries. Measurements were also performed to characterize the MF exposure of cashiers. Cashiers were found to be exposed to 8.2 MHz MFs only when passing by the gates at short distance. Static fields of about 0.1 mT were observed at cashier's seat. Extremely low frequency MFs were higher at stores without EAS devices. No differences on the risk of miscarriage, reduced birth weight or preterm birth were observed between cashiers in different store types. Any further studies should attempt to include study subjects working near EAS systems that produce stronger IF MFs at kHz frequencies. Exposure to ELF MFs should be assessed as a possible confounding factor.

CONTROL LIMITER DEVICE

DOEpatents

DeShong, J.A.

1960-03-01

A control-limiting device for monltoring a control system is described. The system comprises a conditionsensing device, a condition-varying device exerting a control over the condition, and a control means to actuate the condition-varying device. A control-limiting device integrates the total movement or other change of the condition-varying device over any interval of time during a continuum of overlapping periods of time, and if the tothl movement or change of the condition-varying device exceeds a preset value, the control- limiting device will switch the control of the operated apparatus from automatic to manual control.

Validation of a new whole-body cryotherapy chamber based on forced convection.

PubMed

Bouzigon, Romain; Arfaoui, Ahlem; Grappe, Frédéric; Ravier, Gilles; Jarlot, Benoit; Dugue, Benoit

2017-04-01

Whole-body cryotherapy (WBC) and partial-body cryotherapy (PBC) are two methods of cold exposure (from -110 to -195°C according to the manufacturers). However, temperature measurement in the cold chamber during a PBC exposure revealed temperatures ranging from -25 to -50°C next to the skin of the subjects (using isolating layer placed between the sensor and the skin). This discrepancy is due to the human body heat transfer. Moreover, on the surface of the body, an air layer called the boundary layer is created during the exposure and limits heat transfer from the body to the cabin air. Incorporating forced convection in a chamber with a participant inside could reduce this boundary layer. The aim of this study was to explore the use of a new WBC technology based on forced convection (frontal unilateral wind) through the measurement of skin temperature. Fifteen individuals performed a 3-min WBC exposure at -40°C with an average wind speed of 2.3ms -1 . The subjects wore a headband, a surgical mask, underwear, gloves and slippers. The skin temperature of the participants was measured with a thermal camera just before exposure, just after exposure and at 1, 3, 5, 10, 15 and 20min after exposure. Mean skin temperature significantly dropped by 11°C just after exposure (p<0.001) and then significantly increased during the 20-min post exposure period (p<0.001). No critically low skin temperature was observed at the end of the cold exposure. This decrease was greater than the mean decreases in all the cryosauna devices with reported exposures between -140°C and -160°C and those in two other WBC devices with reported exposures between -60°C and -110°C. The use of this new technology provides the ability to reach decreases in skin temperature similar to other technologies. The new chamber is suitable and relevant for use as a WBC device. Copyright © 2017 Elsevier Ltd. All rights reserved.

Exposure to radio frequency electromagnetic fields from wireless computer networks: duty factors of Wi-Fi devices operating in schools.

PubMed

Khalid, M; Mee, T; Peyman, A; Addison, D; Calderon, C; Maslanyj, M; Mann, S

2011-12-01

The growing use of wireless local area networks (WLAN) in schools has prompted a study to investigate exposure to the radio frequency (RF) electromagnetic fields from Wi-Fi devices. International guidelines on limiting the adverse health effects of RF, such as those of ICNIRP, allow for time-averaging of exposure. Thus, as Wi-Fi signals consist of intermittent bursts of RF energy, it is important to consider the duty factors of devices in assessing the extent of exposure and compliance with guidelines. Using radio packet capture methods, the duty factor of Wi-Fi devices has been assessed in a sample of 6 primary and secondary schools during classroom lessons. For the 146 individual laptops investigated, the range of duty factors was from 0.02 to 0.91%, with a mean of 0.08% (SD 0.10%). The duty factors of access points from 7 networks ranged from 1.0% to 11.7% with a mean of 4.79% (SD 3.76%). Data gathered with transmit time measuring devices attached to laptops also showed similar results. Within the present limited sample, the range of duty factors from laptops and access points were found to be broadly similar for primary and secondary schools. Applying these duty factors to previously published results from this project, the maximum time-averaged power density from a laptop would be 220 μW m(-2), at a distance of 0.5 m and the peak localised SAR predicted in the torso region of a 10 year old child model, at 34 cm from the antenna, would be 80 μW kg(-1). Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Occupational exposure to styrene in the fibreglass reinforced plastic industry: comparison between two different manufacturing processes.

PubMed

Tranfo, Giovanna; Gherardi, Monica; Paci, E; Gatto, Mariapia; Gordiani, A; Caporossi, Lidia; Capanna, Silvia; Sisto, Renata; Papaleo, B; Fiumalbi, Carla; Garofani, Patrizia

2012-01-01

Styrene is used in manufacturing fiberglass reinforced plastics: and occupational exposure was related to neurotoxicology and genotoxicity. The sum of the metabolites mandelic and phenylglyoxylic acids is the ACGIH biomarker for occupational exposure with a BEI of 400 mg/g of creatinine in end shift urine corresponding to a airborne styrene concentration of 85 mg/m3. There are two main molding processes, open and closed, the last more effective at controlling worker's styrene exposure. To compare the open molding process to the compression of fiber reinforced resin foils, a kind of closed molding, monitoring the styrene exposure of workers in two production sites (A and B). Environmental Monitoring was carried out by Radiello samplers and Biological Monitoring by means of the determination of MA and PGA with HPLC/MS/MS in 10 workers at Site A and 14 at Site B. The median values for styrene exposure resulted 31.1 mg/m3 for Site A and 24.4 mg/m for Site B, while the medians for the sum of the two metabolites in the end shift urine were 86.7 e 33.8 mg/g creatinine respectively. There is a significant linear correlation between personal styrene exposure and the excretion of styrene metabolites (R = 0.74). As expected the exposure markers of the workers of the two production sites resulted higher in the open process. The analytical results of both environmental and biological monitoring were all below the occupational exposure limits, confirming the efficacy of the protective devices.

Medical and policy considerations for nuclear and radiation accidents, incidents and terrorism.

PubMed

Gale, Robert Peter

2017-11-01

The purpose of this review is to address the increasing medical and public concern regarding the health consequences of radiation exposure, a concern shaped not only by fear of another Chernobyl or Fukushima nuclear power facility accident but also by the intentional use of a nuclear weapon, a radiological dispersion device, a radiological exposure device, or an improved nuclear device by rogue states such as North Korea and terrorist organizations such as Al Qaeda and ISIS. The United States has the medical capacity to respond to a limited nuclear or radiation accident or incident but an effective medical response to a catastrophic nuclear event is impossible. Dealing effectively with nuclear and radiation accidents or incidents requires diverse strategies, including policy decisions, public education, and medical preparedness. I review medical consequences of exposures to ionizing radiations, likely concomitant injuries and potential medical intervention. These data should help haematologists and other healthcare professionals understand the principles of medical consequences of nuclear terrorism. However, the best strategy is prevention.

[Ultraviolet exposure from indoor tanning devices as a potential source of health risks: Basic knowledge of the proper use of these devices for practical users, physicians and solarium staff].

PubMed

Malinowska-Borowska, Jolanta; Janosik, Elżbieta

2017-07-26

Bearing in mind the adverse health effects of exposure to ultraviolet (UV) radiation in solarium, especially the risk of carcinogenesis, there is a need to adopt legal regulations by relevant Polish authorities. They should set out the principles for indoor tanning studios operation, supervision and service of the technical parameters of tanning devices and training programs to provide the staff with professional knowledge and other aspects of safety in these facilities. The mechanism of the harmful effects of ultraviolet radiation on the human body, scale of overexposure, resulting from excessive sunbathing are described. Methods for estimating UV exposure and possible actions aimed at reducing the overexposure and preventing from cancer development caused by UV are also presented in this paper. Med Pr 2017;68(5):653-665. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Evaluation of electromagnetic interference and exposure assessment from s-health solutions based on Wi-Fi devices.

PubMed

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

2015-01-01

In the last decade the number of wireless devices operating at the frequency band of 2.4 GHz has increased in several settings, such as healthcare, occupational, and household. In this work, the emissions from Wi-Fi transceivers applicable to context aware scenarios are analyzed in terms of potential interference and assessment on exposure guideline compliance. Near field measurement results as well as deterministic simulation results on realistic indoor environments are presented, providing insight on the interaction between the Wi-Fi transceiver and implantable/body area network devices as well as other transceivers operating within an indoor environment, exhibiting topological and morphological complexity. By following approaches (near field estimation/deterministic estimation), colocated body situations as well as large indoor emissions can be determined. The results show in general compliance with exposure levels and the impact of overall network deployment, which can be optimized in order to reduce overall interference levels while maximizing system performance.

Evaluation of Electromagnetic Interference and Exposure Assessment from s-Health Solutions Based on Wi-Fi Devices

PubMed Central

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

2015-01-01

In the last decade the number of wireless devices operating at the frequency band of 2.4 GHz has increased in several settings, such as healthcare, occupational, and household. In this work, the emissions from Wi-Fi transceivers applicable to context aware scenarios are analyzed in terms of potential interference and assessment on exposure guideline compliance. Near field measurement results as well as deterministic simulation results on realistic indoor environments are presented, providing insight on the interaction between the Wi-Fi transceiver and implantable/body area network devices as well as other transceivers operating within an indoor environment, exhibiting topological and morphological complexity. By following approaches (near field estimation/deterministic estimation), colocated body situations as well as large indoor emissions can be determined. The results show in general compliance with exposure levels and the impact of overall network deployment, which can be optimized in order to reduce overall interference levels while maximizing system performance. PMID:25632400

Improved intensifying screen reduces X-ray exposure

NASA Technical Reports Server (NTRS)

Buchanan, R. A.

1972-01-01

X-ray intensifying screen may make possible radiographic procedures where detection speed and X-ray tube power have been the limiting factors. Device will reduce total population exposure to harmful radiation in the United States.

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

Code of Federal Regulations, 2012 CFR

2012-10-01

... for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to... Exposure Criteria for Radiofrequency Electromagnetic Fields,” NCRP Report No. 86, Section 17.4.5. Copyright... Electromagnetic Fields—RF and Microwave,” IEEE C95.3-1991. (4) For purposes of analyzing portable transmitting...

Occupational exposure of personnel operating military radio equipment: measurements and simulation.

PubMed

Paljanos, Annamaria; Miclaus, Simona; Munteanu, Calin

2015-09-01

Technical literature provides numerous studies concerning radiofrequency exposure measurements for various radio communication devices, but there are few studies related to exposure of personnel operating military radio equipment. In order to evaluate exposure and identify cases when safety requirements are not entirely met, both measurements and simulations are needed for accurate results. Moreover, given the technical characteristics of the radio devices used in the military, personnel mainly operate in the near-field region so both measurements and simulation becomes more complex. Measurements were made in situ using a broadband personal exposimeter equipped with two isotropic probes for both electric and magnetic components of the field. The experiment was designed for three different operating frequencies of the same radio equipment, while simulations were made in FEKO software using hybrid numerical methods to solve complex electromagnetic field problems. The paper aims to discuss the comparative results of the measurements and simulation, as well as comparing them to reference levels specified in military or civilian radiofrequency exposure standards.

Early-Onset Basal Cell Carcinoma and Indoor Tanning: A Population-Based Study

PubMed Central

Zens, M. Scot; Li, Zhigang; Stukel, Therese A.; Perry, Ann E.; Gilbert-Diamond, Diane; Sayarath, Vicki; Stephenson, Rita S.; Barton, Dorothea; Nelson, Heather H.; Spencer, Steven K.

2014-01-01

OBJECTIVE: Indoor tanning with UV radiation–emitting lamps is common among adolescents and young adults. Rising incidence rates of basal cell carcinoma (BCC) have been reported for the United States and elsewhere, particularly among those diagnosed at younger ages. Recent epidemiologic studies have raised concerns that indoor tanning may be contributing to early occurrence of BCC, and younger people may be especially vulnerable to cancer risk associated with this exposure. Therefore, we sought to address these issues in a population-based case–control study from New Hampshire. METHODS: Data on indoor tanning were obtained on 657 cases of BCC and 452 controls ≤50 years of age. RESULTS: Early-onset BCC was related to indoor tanning, with an adjusted odds ratio (OR) of 1.6 (95% confidence interval, 1.3–2.1). The strongest association was observed for first exposure as an adolescent or young adult, with a 10% increase in the OR with each age younger at first exposure (OR per year of age ≤23 = 1.1; 95% confidence interval, 1.0–1.2). Associations were present for each type of device examined (ie, sunlamps, tanning beds, and tanning booths). CONCLUSIONS: Our findings suggest early exposure to indoor tanning increases the risk of early development of BCC. They also underscore the importance of counseling adolescents and young adults about the risks of indoor tanning and for discouraging parents from consenting minors to this practice. PMID:24958589

Early-onset basal cell carcinoma and indoor tanning: a population-based study.

PubMed

Karagas, Margaret R; Zens, M Scot; Li, Zhigang; Stukel, Therese A; Perry, Ann E; Gilbert-Diamond, Diane; Sayarath, Vicki; Stephenson, Rita S; Barton, Dorothea; Nelson, Heather H; Spencer, Steven K

2014-07-01

Indoor tanning with UV radiation-emitting lamps is common among adolescents and young adults. Rising incidence rates of basal cell carcinoma (BCC) have been reported for the United States and elsewhere, particularly among those diagnosed at younger ages. Recent epidemiologic studies have raised concerns that indoor tanning may be contributing to early occurrence of BCC, and younger people may be especially vulnerable to cancer risk associated with this exposure. Therefore, we sought to address these issues in a population-based case-control study from New Hampshire. Data on indoor tanning were obtained on 657 cases of BCC and 452 controls ≤50 years of age. Early-onset BCC was related to indoor tanning, with an adjusted odds ratio (OR) of 1.6 (95% confidence interval, 1.3-2.1). The strongest association was observed for first exposure as an adolescent or young adult, with a 10% increase in the OR with each age younger at first exposure (OR per year of age ≤23 = 1.1; 95% confidence interval, 1.0-1.2). Associations were present for each type of device examined (ie, sunlamps, tanning beds, and tanning booths). Our findings suggest early exposure to indoor tanning increases the risk of early development of BCC. They also underscore the importance of counseling adolescents and young adults about the risks of indoor tanning and for discouraging parents from consenting minors to this practice. Copyright © 2014 by the American Academy of Pediatrics.

Cochlear Damages Caused by Vibration Exposure

PubMed Central

Moussavi Najarkola, Seyyed Ali; Khavanin, Ali; Mirzaei, Ramazan; Salehnia, Mojdeh; Muhammadnejad, Ahad

2013-01-01

Background Many industrial devices have an excessive vibration which can affect human body systems. The effect of vibration on cochlear histology has been as a debatable problem in occupational health and medicine. Objectives Due to limitation present in human studies, the research was conducted to survey the influence of vibration on cochlear histology in an animal model. Materials and Methods Twelve albino rabbits were experimented as: Vibration group (n = 6; exposed to 1.0 m.s-2 r.m.s vertical whole-body vibration at 4 - 8 Hz for 8 hours per day during 5 consecutive days) versus Control group (n = 6; the same rabbits without vibration exposure). After finishing the exposure scenario, all rabbits were killed by CO2 inhalation; their cochleae were extracted and fixed in 10% formaldehyde for 48 hours, decalcified by 10% nitric acid for 24 hours. Specimens were dehydrated, embedded, sectioned 5 µm thick and stained with Hematoxylin and Eosin for light microscopy observations. Results Severely hydropic degenerated and vacuolated inner hair cells (IHCs) were observed in vibration group compared to the control group. Inter and intracellular edema was appeared in supporting cells (SC). Nuclei of outer hair cells (OHCs) seemed to be pyknotic. Slightly thickened basilar membrane (BM) was probably implied to inter cellular edematous. Tectorial Membrane (TM) was not affected pathologically. Conclusions Whole-body vibration could cause cochlear damages in male rabbits, though vibration-induced auditory functional effects might be resulted as subsequent outcome of prolonged high level vibration exposures. PMID:24616783

SU-8 negative photoresist for optical mask manufacturing

NASA Astrophysics Data System (ADS)

Bogdanov, Alexei L.

2000-06-01

The requirements for better control, linearity, and uniformity of critical dimension (CD) on photomasks in fabrication of 180 and 150 nm generation devices result in increasing demand for thinner, more etching durable, and more sensitive e-beam resists. Novolac based resists with chemical amplification have been a choice for their sensitivity and stability during etching. However, difficult CD control due to the acid catalyzer diffusion and quite narrow post exposure bake (PEB) process window are some of the major drawbacks of these resists. SU-8 is recently introduced to the market negative photoresist. High sensitivity, fairly good adhesion properties, and relatively simple processing of SU-8 make it a good substitution for novolac based chemically amplified negative e-beam resists in optical mask manufacturing. The replacement of traditional chemically amplified resists by SU- 8 can increase the process latitude and reduce resist costs. Among the obvious drawbacks of SU-8 are the use of solvent- based developer and demand of oxygen plasma for resist removal. In this paper the use of SU-8 for optical mask manufacturing is reported. All steps of resist film preparation, exposure and development are paid a share of attention. Possibilities to use reactive ion etching (RIE) with oxygen in order to increase resist mask contrast are discussed. Special exposure strategy (pattern outlining) was employed to further improve the edge definition. The resist PEB temperature and time were studied to estimate their weight in overall CD control performance. Specially designed test patterns with 0.25 micrometer design rule could be firmly transferred into a chromium layer both by wet etching and ion milling. Influence of exposure dose variation on the pattern CD change was studied.

Aerosol Stable Peptide-Coated Liposome Nanoparticles: A Proof-of-Concept Study with Opioid Fentanyl in Enhancing Analgesic Effects and Reducing Plasma Drug Exposure

PubMed Central

HOEKMAN, JOHN D; SRIVASTAVA, PRAMOD; HO, RODNEY J Y

2014-01-01

Previous we reported a novel pressurized olfactory drug (POD) delivery device that deposit aerosolized drug preferentially to upper nasal cavity. This POD device provided sustained CNS levels of soluble morphine analgesic effects. However, analgesic onset of less soluble fentanyl was more rapid but brief, likely due to hydrophobic fentanyl redistribution readily back to blood. To determine whether fentanyl incorporated into an aerosol stable liposome that binds to nasal epithelial cells will enhance CNS drug exposure and analgesic effects and reduce plasma exposure, we constructed RGD liposomes anchored with acylated integrin binding peptides (palmitoyl-GRGDS). The RGD liposomes, which assume gel-phase membrane structure at 25°C were stable under the stress of aerosolization as only 2.2 ± 0.5 % calcein leakage detected. The RGD mediated integrin binding of liposome is also verified to be unaffected by aerosolization. Rats treated with fentanyl in RGD-liposome and POD device exhibited greater analgesic effect, compared to the free drug counterpart (AUCeffect = 1387.l vs. 760.1 %MPE*min); while ~20% reduced plasma drug exposure was noted (AUC0-120 = 208.2 vs 284.8 ng*min/ml). Collectively, fentanyl incorporated in RGD-liposomes are physically and biologically stable under aerosolization, enhanced the overall analgesic effects and reduced plasma drug exposure for the first 2 hours. PMID:24909764

Assessment of exposure to radio frequency electromagnetic fields from smart utility meters in GB; part II) numerical assessment of induced SAR within the human body.

PubMed

Qureshi, Muhammad R A; Alfadhl, Yasir; Chen, Xiaodong; Peyman, Azadeh; Maslanyj, Myron; Mann, Simon

2018-04-01

Human body exposure to radiofrequency electromagnetic waves emitted from smart meters was assessed using various exposure configurations. Specific energy absorption rate distributions were determined using three anatomically realistic human models. Each model was assigned with age- and frequency-dependent dielectric properties representing a collection of age groups. Generalized exposure conditions involving standing and sleeping postures were assessed for a home area network operating at 868 and 2,450 MHz. The smart meter antenna was fed with 1 W power input which is an overestimation of what real devices typically emit (15 mW max limit). The highest observed whole body specific energy absorption rate value was 1.87 mW kg -1 , within the child model at a distance of 15 cm from a 2,450 MHz device. The higher values were attributed to differences in dimension and dielectric properties within the model. Specific absorption rate (SAR) values were also estimated based on power density levels derived from electric field strength measurements made at various distances from smart meter devices. All the calculated SAR values were found to be very small in comparison to International Commission on Non-Ionizing Radiation Protection limits for public exposure. Bioelectromagnetics. 39:200-216, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

In-vacuum exposure shutter

DOEpatents

Johnson, Terry A.; Replogle, William C.; Bernardez, Luis J.

2004-06-01

An in-vacuum radiation exposure shutter device can be employed to regulate a large footprint light beam. The shutter device includes (a) a source of radiation that generates an energy beam; (2) a shutter that includes (i) a frame defining an aperture toward which the energy beam is directed and (ii) a plurality of blades that are secured to the frame; and (3) device that rotates the shutter to cause the plurality of blades to intercept or allow the energy beam to travel through the aperture. Each blade can have a substantially planar surface and the plurality of blades are secured to the frame such that the planar surfaces of the plurality of blades are substantially parallel to each other. The shutter device is particularly suited for operation in a vacuum environment and can achieve shuttering speeds from about 0.1 second to 0.001 second or faster.

Small, Smart, Fast, and Cheap: Microchip-Based Sensors to Estimate Air Pollution Exposures in Rural Households

PubMed Central

Pillarisetti, Ajay; Allen, Tracy; Ruiz-Mercado, Ilse; Edwards, Rufus; Chowdhury, Zohir; Garland, Charity; Johnson, Michael; Litton, Charles D.; Lam, Nicholas L.; Pennise, David; Smith, Kirk R.

2017-01-01

Over the last 20 years, the Kirk R. Smith research group at the University of California Berkeley—in collaboration with Electronically Monitored Ecosystems, Berkeley Air Monitoring Group, and other academic institutions—has developed a suite of relatively inexpensive, rugged, battery-operated, microchip-based devices to quantify parameters related to household air pollution. These devices include two generations of particle monitors; data-logging temperature sensors to assess time of use of household energy devices; a time-activity monitoring system using ultrasound; and a CO2-based tracer-decay system to assess ventilation rates. Development of each system involved numerous iterations of custom hardware, software, and data processing and visualization routines along with both lab and field validation. The devices have been used in hundreds of studies globally and have greatly enhanced our understanding of heterogeneous household air pollution (HAP) concentrations and exposures and factors influencing them. PMID:28812989

Small, Smart, Fast, and Cheap: Microchip-Based Sensors to Estimate Air Pollution Exposures in Rural Households.

PubMed

Pillarisetti, Ajay; Allen, Tracy; Ruiz-Mercado, Ilse; Edwards, Rufus; Chowdhury, Zohir; Garland, Charity; Hill, L Drew; Johnson, Michael; Litton, Charles D; Lam, Nicholas L; Pennise, David; Smith, Kirk R

2017-08-16

Over the last 20 years, the Kirk R. Smith research group at the University of California Berkeley-in collaboration with Electronically Monitored Ecosystems, Berkeley Air Monitoring Group, and other academic institutions-has developed a suite of relatively inexpensive, rugged, battery-operated, microchip-based devices to quantify parameters related to household air pollution. These devices include two generations of particle monitors; data-logging temperature sensors to assess time of use of household energy devices; a time-activity monitoring system using ultrasound; and a CO₂-based tracer-decay system to assess ventilation rates. Development of each system involved numerous iterations of custom hardware, software, and data processing and visualization routines along with both lab and field validation. The devices have been used in hundreds of studies globally and have greatly enhanced our understanding of heterogeneous household air pollution (HAP) concentrations and exposures and factors influencing them.

Occlusive ligature and standardized fenestration of a Baerveldt tube with and without antimetabolites for early postoperative intraocular pressure control.

PubMed

Trible, J R; Brown, D B

1998-12-01

To determine the effectiveness of a surgical modification for a nonvalved aqueous tube shunt in controlling intraocular pressure (IOP) in the early postoperative period. The effect of antimetabolite use on IOP also was studied. A retrospective study of consecutive patients who underwent modified Baerveldt 350-mm2 implant with varied, nonrandomized, exposure to antimetabolites. Fifty-one eyes of 46 patients with uncontrolled glaucoma were examined. Identical surgical modification of a Baerveldt 350-mm2 tube was performed in all cases and consisted of placement of an occlusive 7-0 polyglactin suture just anterior to the plate followed by a through-and-through penetration of the tube just anterior to the occlusive ligature with a standardized 15 degrees blade. Seventeen eyes were not exposed to antimetabolite, while 2 groups of 17 eyes had 3 minutes' episcleral exposure to either 5-fluorouracil 50 mg/ml or mitomycin C 0.4 mg/ml at the location corresponding to the fenestration. The Tenon's layer and conjunctiva were not exposed because of concerns regarding conjunctival erosion over the device. Intraocular pressure and number of antiglaucoma medications required were analyzed. For the group, mean IOP before surgery and on postoperative days 1, 4, 10, 21, 42, 63, 84, and 112 was (in millimeters of mercury) 34.6, 20.1, 17.0, 17.2, 22.0, 17.3, 18.7, 17.4, and 15.6, respectively. There was an elevation of IOP at day 21 relative to fibrotic blockage of the fenestration before suture autolysis. This was temporized with antiglaucoma medication until suture autolysis occurred or treated with laser suture lysis (8 eyes). On day 1, hypotony occurred in 3 (6%) eyes whereas IOP greater than 30 mmHg was observed in 13 (26%) eyes. By day 10, the frequency had decreased to one (2.1 %) eye and three (6.4%) eyes, respectively. The use of antimetabolites did not result in lower IOP or less medication needed for any group at any interval (analysis of variance). This modification of a nonvalved glaucoma tube shunt device provides adequate IOP control in the early postoperative period with a low rate of hypotony and surgical complications. If elevation of IOP occurs before suture autolysis, it generally is well controlled by antiglaucoma medications or laser suture lysis. Antimetabolite exposure did not influence early postoperative IOP in this study.

Evaluation of thermal and non-thermal effects of UHF RFID exposure on biological drugs.

PubMed

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.

Effect of UV/ozone treatment on polystyrene dielectric and its application on organic field-effect transistors

PubMed Central

2014-01-01

The influence of UV/ozone treatment on the property of polystyrene (PS) dielectric surface was investigated, and pentacene organic field-effect transistors (OFETs) based on the treated dielectric was fabricated. The dielectric and pentacene active layers were characterized by atomic force microscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. The results showed that, at short UVO exposure time (<10 s), the chemical composition of PS dielectric surface remained the same. While at long UVO exposure time (>60 s), new chemical groups, including alcohol/ether, carbonyl, and carboxyl/ester groups, were formed. By adjusting the UVO exposure time to 5 s, the hole mobility of the OFETs increased to 0.52 cm2/Vs, and the threshold voltage was positively shifted to -12 V. While the time of UVO treatment exceeded 30 s, the mobility started to shrink, and the off-current was enlarged. These results indicate that, as a simple surface treatment method, UVO treatment could quantitatively modulate the property of PS dielectric surface by controlling the exposure time, and thus, pioneered a new way to modulate the characteristics of organic electronic devices. PMID:25258603

3D conformal MRI-guided transurethral ultrasound therapy: results of gel phantom experiments

NASA Astrophysics Data System (ADS)

N'Djin, W. A.; Burtnyk, M.; McCormick, S.; Bronskill, M.; Chopra, R.

2011-09-01

MRI-guided transurethral ultrasound therapy shows promise for minimally invasive treatment of localized prostate cancer. Previous in-vivo studies demonstrated the feasibility of performing conservative treatments using real-time temperature feedback to control accurately the establishment of coagulative lesions within circumscribed prostate regions. This in-vitro study tested device configuration and control options for achieving full prostate treatments. A multi-channel MRI compatible ultrasound therapy system was evaluated in gel phantoms using 3 canine prostate models. Prostate profiles were 5 mm-step-segmented from T2-weighted MR images performed during previous in-vivo experiments. During ultrasound exposures, each ultrasound element was controlled independently by the 3D controller. Decisions on acoustic power, frequency, and device rotation rate were made in real time based on MR thermometry feedback and prostate radii. Low and high power treatment approaches using maximum acoustic powers of 10 or 20 W.cm-2 were tested as well as single and dual-frequency strategies (4.05/13.10 MHz). The dual-frequency strategy used either the fundamental frequency or the 3rd harmonic component, depending on the prostate radius. The 20 W.cm-2 dual frequency approach was the most efficient configuration in achieving full prostate treatments. Treatment times were about half the duration of those performed with 10 W.cm-2 configurations. Full prostate coagulations were performed in 16.3±6.1 min at a rate of 1.8±0.2 cm3.min-1, and resulted in very little undertreated tissue (<3%). Surrounding organs positioned beyond a safety distance of 1.4±1.0 mm from prostate boundaries were not damaged, particularly rectal wall tissues. In this study, a 3D, MR-thermometry-guided transurethral ultrasound therapy was validated in vitro in a tissue-mimicking phantom for performing full prostate treatment. A dual-frequency configuration with 20 W.cm-2 ultrasound intensity exposure showed good results with direct application to full human prostate treatments.

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

Code of Federal Regulations, 2014 CFR

2014-10-01

... of part 1 of this chapter, in particular § 1.1307(b). (b) For purposes of this section, a mobile device is defined as a transmitting device designed to be used in other than fixed locations and to generally be used in such a way that a separation distance of at least 20 centimeters is normally maintained...

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

Code of Federal Regulations, 2013 CFR

2013-10-01

... of part 1 of this chapter, in particular § 1.1307(b). (b) For purposes of this section, a mobile device is defined as a transmitting device designed to be used in other than fixed locations and to generally be used in such a way that a separation distance of at least 20 centimeters is normally maintained...

NIR camera and spectrograph SWIMS for TAO 6.5m telescope: array control system and its performance

NASA Astrophysics Data System (ADS)

Terao, Yasunori; Motohara, Kentaro; Konishi, Masahiro; Takahashi, Hidenori; Kato, Natsuko M.; Kitagawa, Yutaro; Kobayakawa, Yutaka; Ohashi, Hirofumi; Tateuchi, Ken; Todo, Soya

2016-08-01

SWIMS (Simultaneous-color Wide-field Infrared Multi-object Spectrograph) is a near-infrared imager and multi-object spectrograph as one of the first generation instruments for the University of Tokyo Atacama Observatory (TAO) 6.5m telescope. In this paper, we describe an array control system of SWIMS and results of detector noise performance evaluation. SWIMS incorporates four (and eight in future) HAWAII-2RG focal plane arrays for detectors, each driven by readout electronics components: a SIDECAR ASIC and a JADE2 Card. The readout components are controlled by a HAWAII-2RG Testing Software running on a virtual Windows machine on a Linux PC called array control PC. All of those array control PCs are then supervised by a SWIMS control PC. We have developed an "array control software system", which runs on the array control PC to control the HAWAII-2RG Testing Software, and consists of a socket client and a dedicated server called device manager. The client runs on the SWIMS control PC, and the device manager runs on the array control PC. An exposure command, issued by the client on the SWIMS control PC, is sent to the multiple device managers on the array control PCs, and then multiple HAWAII-2RGs are driven simultaneously. Using this system, we evaluate readout noise performances of the detectors, both in a test dewar and in a SWIMS main dewar. In the test dewar, we confirm the readout noise to be 4.3 e- r.m.s. by 32 times multiple sampling when we operate only a single HAWAII-2RG, whereas in the case of simultaneous driving of two HAWAII-2RGs, we still obtain sufficiently low readout noise of 10 e- r.m.s. In the SWIMS main dewar, although there are some differences between the detectors, the readout noise is measured to be 4:1-4:6 e- r.m.s. with simultaneous driving by 64 times multiple sampling, which meets the requirement for background-limited observations in J band of 14 e- r.m.s..

A Multisite Study of the Relationships between Blast Exposures and Symptom Reporting in a Post-Deployment Active Duty Military Population with Mild Traumatic Brain Injury

PubMed Central

Miller, Kelly J.; Lange, Rael T.; Cooper, Douglas B.; Tate, David F.; Bailie, Jason; Brickell, Tracey A.; French, Louis M.; Asmussen, Sarah; Kennedy, Jan E.

2014-01-01

Abstract Explosive devices have been the most frequent cause of traumatic brain injury (TBI) among deployed contemporary U.S. service members. The purpose of this study was to examine the influence of previous cumulative blast exposures (that did or did not result in TBI) on later post-concussion and post-traumatic symptom reporting after sustaining a mild TBI (MTBI). Participants were 573 service members who sustained MTBI divided into four groups by number of blast exposures (1, 2, 3, and 4–10) and a nonblast control group. Post-concussion symptoms were measured using the Neurobehavioral Symptom Inventory (NSI) and post-traumatic stress disorder (PTSD) symptoms using the Post-traumatic Checklist-Civilian version (PCL-C). Results show groups significantly differed on total NSI scores (p<0.001), where symptom endorsement increased as number of reported blast exposures increased. Total NSI scores were significantly higher for the 3– and 4–10 blast groups compared with the 1- and 2-blast groups with effect sizes ranging from small to moderate (d=0.31 to 0.63). After controlling for PTSD symptoms using the PCL-C total score, NSI total score differences remained between the 4–10-blast group and the 1- and 2-blast groups, but were less pronounced (d=0.35 and d=0.24, respectively). Analyses of NSI subscale scores using PCL-C scores as a covariate revealed significant between-blast group differences on cognitive, sensory, and somatic, but not affective symptoms. Regression analyses revealed that cumulative blast exposures accounted for a small but significant amount of the variance in total NSI scores (4.8%; p=0.009) and total PCL-C scores (2.3%; p<0.001). Among service members exposed to blast, post-concussion symptom reporting increased as a function of cumulative blast exposures. Future research will need to determine the relationship between cumulative blast exposures, symptom reporting, and neuropathological changes. PMID:25036531

Non-Ionizing Radiation From Wireless Technology| RadTown ...

EPA Pesticide Factsheets

2017-10-31

Cell phones emit radio frequency (RF) energy. The Federal Communications Commission (FCC) sets safety guidelines to limit RF exposure from wireless devices. Scientists continue to study the effects of long-term exposure to low levels of RF.

[AOR characterization and zoning: a dosimeter for blue light].

PubMed

Dario, R; Uva, J; Di Lecce, V; Quarto, A

2011-01-01

The paper presents the results obtained thanks to an innovative experimental device for the assessment of artificial optical radiation (AOR) exposure in workplace. This . device was developed by 'Politecnico di Bari-DIASS'. The wearable personal dosimeter has three sensors: one is used for measuring head position/movement, therefore there is a color light sensor to determine the AOR and finally there is a video camera to localize sources. Our system is connected to a netbook via USB cable that allows one to obtain the real and extimated value of worker's exposure, also with "augmented reality". The aim of this paper is realizing work place safety zoning for the classifacation of not only specific dangerous areas through the analysis of overlapping information from the device.

Prevalence of permanent hearing threshold shift among workers of Indian iron and steel small and medium enterprises: a study.

PubMed

Singh, Lakhwinder Pal; Bhardwaj, Arvind; Kumar, Deepak Kishore

2012-01-01

Occupational noise exposure and noise-induced hearing loss (NIHL) have been recognized as a problem among workers in Indian industries. The major industries in India are based on manufacturing. There are appreciable numbers of casting and forging units spread across the country. The objective of this study is to determine the prevalence of permanent hearing threshold shift among the workers engaged in Indian iron and steel small and medium enterprises (SMEs) and compared with control group subjects. As a part of hearing protection intervention, audiometric tests were conducted at low (250-1000 Hz), medium (1500-3000 Hz), and high (4000-8000 Hz) frequencies. The occurrence of hearing loss was determined based on hearing threshold levels with a low fence of 25 dB. Comparisons were made for hearing threshold at different frequencies between the exposed and control groups using Student's t test. ANOVA was used for the comparison of hearing threshold dB at different frequencies among occupation and year of experience. A P value <0.05 was considered as statistically significant. All data were presented as mean value (SD). Over 90% of workers engaged in various processes of casting and forging industry showed hearing loss in the noise-sensitive medium and higher frequencies. Occupation was significantly associated with NIHL, and hearing loss was particularly high among the workers of forging section. The analyses revealed a higher prevalence of significant hearing loss among the forging workers compared to the workers associated with other activities. The study shows alarming signals of NIHL, especially in forging workers. The occupational exposure to noise could be minimized by efficient control measures through engineering controls, administrative controls, and the use of personal protective devices. Applications of engineering and/or administrative controls are frequently not feasible in the developing countries for technical and financial reasons. A complete hearing conservation programme, including training, audiometry, job rotation, and the use of hearing protection devices, is the most feasible method for the protection of industrial workers from prevailing noise in workplace environments in the developing countries.

Justification and good practice in using handheld portable dental X-ray equipment: a position paper prepared by the European Academy of DentoMaxilloFacial Radiology (EADMFR)

PubMed Central

Suomalainen, A; Brüllmann, D; Jacobs, R; Horner, K; Stamatakis, H C

2015-01-01

Handheld portable X-ray devices are increasingly used for intraoral radiography. This development introduces new challenges to staff and patient safety, for which new or revised risk assessments must be made and acted upon prior to use. Major issues might be: difficulties in using rectangular collimation with beam aiming devices, more complex matching of exposure settings to the X-ray receptor used (e.g. longer exposure times), movements owing to the units' weight, protection of the operator and third persons, and the use in uncontrolled environments. These problems may result in violation of the “as low as reasonably achievable’’, that is, ALARA principle by an increase in (re)exposures compared with the other available intraoral X-ray devices. Hence, the use of handheld portable X-ray devices should be considered only after careful and documented evaluation (which might be performed based on medical physics support), when there is evidence that handheld operation has benefits over traditional modalities and when no new risks to the operators and/or third parties are caused. It is expected that the use of handheld portable X-ray devices will be very exceptional, and for justified situations only. Special attention should be drawn to beam-aiming devices, rectangular collimation, the section of the X-ray receptor, focus–skin distance, and backscatter shielding, and that the unit delivers reproducible dose over the full set of environmental conditions (e.g. battery status and temperature). PMID:25710118

Magnetic-field-dosimetry system

DOEpatents

Lemon, D.K.; Skorpik, J.R.; Eick, J.L.

1981-01-21

A device is provided for measuring the magnetic field dose and peak field exposure. The device includes three Hall-effect sensors all perpendicular to each other, sensing the three dimensional magnetic field and associated electronics for data storage, calculating, retrieving and display.

Controlling and prevention of surface wrinkling via size-dependent critical wrinkling strain.

PubMed

Han, Xue; Zhao, Yan; Cao, Yanping; Lu, Conghua

2015-06-14

Surface wrinkling may occur in a film-substrate system when the applied strain exceeds the critical value. However, the practically required strain for the onset of surface wrinkling can be different from the theoretically predicted value. Here we investigate the film size effect-dependent critical strain for the mechanical strain-induced surface wrinkling via a combination of experiments and theoretical analysis. In the poly(dimethylsiloxane)-based system fabricated by the smart combination of mechanical straining and selective O2 plasma (OP) exposure through Cu grids, the film size effect on the critical wrinkling strain is systematically studied by considering OP exposure duration, the mesh number and geometry of Cu grids. Meanwhile, a simple analytical solution revealing the film size effect is well established, which shows good consistency with the experimental results. This study provides an experimental and theoretical basis for finely tuning the critical wrinkling strain in a simple and quantitative manner, which can find a wide range of applications in such fields as microelectronic circuits and optical devices, where controlling and/or prevention of surface wrinkling are of great importance.

Revisiting the role of durable polymers in cardiovascular devices.

PubMed

Mori, Hiroyoshi; Otsuka, Fumiyuki; Gupta, Anuj; Jinnouchi, Hiroyuki; Torii, Sho; Harari, Emanuel; Virmani, Renu; Finn, Aloke V

2017-11-01

Polymers are an essential component of drug-eluting stents (DES) used to control drug release but remain the most controversial component of DES technology. There are two types of polymers employed in DES: durable polymer based DES (DP-DES) and biodegradable polymer DES (BP-DES). First-generation DES were exclusively composed of DP and demonstrated increased rates of late stent failure due in part to poor polymer biocompatibility. Newer generations DES use more biocompatible durable polymers or biodegradable polymers. Areas covered: We will cover issues identified with 1st-generation DP-DES, areas of success and failure in 2nd-generation DP-DES and examine the promise and shortcomings of BP-DES. Briefly, fluorinated polymers used in 2nd-generation DP-DES have excellent anti-thrombogenicity and better biocompatibility than 1st-generation DES polymers. However, these devices lead to persistent drug exposure to the endothelium which impairs endothelial function and predisposes towards neoatherosclerosis. Meanwhile, BP-DES has shortened the duration of drug exposure which might be beneficial for endothelial functional recovery leading to less neoatherosclerosis. However, it remains uncertain whether the long-term biocompatibility of bare metal surfaces is better than that of polymer-coated metals. Expert commentary: Each technology has distinct advantages, which can be optimized depending upon the particular characteristics of the patient being treated.

Cybersecurity and medical devices: A practical guide for cardiac electrophysiologists

PubMed Central

Kramer, Daniel B.; Foo Kune, Denis; Auto de Medeiros, Julio; Yan, Chen; Xu, Wenyuan; Crawford, Thomas; Fu, Kevin

2017-01-01

Abstract Medical devices increasingly depend on software. While this expands the ability of devices to perform key therapeutic and diagnostic functions, reliance on software inevitably causes exposure to hazards of security vulnerabilities. This article uses a recent high‐profile case example to outline a proactive approach to security awareness that incorporates a scientific, risk‐based analysis of security concerns that supports ongoing discussions with patients about their medical devices. PMID:28512774

Radial Shock Wave Devices Generate Cavitation

PubMed Central

Császár, Nikolaus B. M.; Angstman, Nicholas B.; Milz, Stefan; Sprecher, Christoph M.; Kobel, Philippe; Farhat, Mohamed; Furia, John P.; Schmitz, Christoph

2015-01-01

Background Conflicting reports in the literature have raised the question whether radial extracorporeal shock wave therapy (rESWT) devices and vibrating massage devices have similar energy signatures and, hence, cause similar bioeffects in treated tissues. Methods and Findings We used laser fiber optic probe hydrophone (FOPH) measurements, high-speed imaging and x-ray film analysis to compare fundamental elements of the energy signatures of two rESWT devices (Swiss DolorClast; Electro Medical Systems, Nyon, Switzerland; D-Actor 200; Storz Medical, Tägerwillen, Switzerland) and a vibrating massage device (Vibracare; G5/General Physiotherapy, Inc., Earth City, MO, USA). To assert potential bioeffects of these treatment modalities we investigated the influence of rESWT and vibrating massage devices on locomotion ability of Caenorhabditis elegans (C. elegans) worms. Results FOPH measurements demonstrated that both rESWT devices generated acoustic waves with comparable pressure and energy flux density. Furthermore, both rESWT devices generated cavitation as evidenced by high-speed imaging and caused mechanical damage on the surface of x-ray film. The vibrating massage device did not show any of these characteristics. Moreover, locomotion ability of C. elegans was statistically significantly impaired after exposure to radial extracorporeal shock waves but was unaffected after exposure of worms to the vibrating massage device. Conclusions The results of the present study indicate that both energy signature and bioeffects of rESWT devices are fundamentally different from those of vibrating massage devices. Clinical Relevance Prior ESWT studies have shown that tissues treated with sufficient quantities of acoustic sound waves undergo cavitation build-up, mechanotransduction, and ultimately, a biological alteration that “kick-starts” the healing response. Due to their different treatment indications and contra-indications rESWT devices cannot be equated to vibrating massage devices and should be used with due caution in clinical practice. PMID:26509573

Radial Shock Wave Devices Generate Cavitation.

PubMed

Császár, Nikolaus B M; Angstman, Nicholas B; Milz, Stefan; Sprecher, Christoph M; Kobel, Philippe; Farhat, Mohamed; Furia, John P; Schmitz, Christoph

2015-01-01

Conflicting reports in the literature have raised the question whether radial extracorporeal shock wave therapy (rESWT) devices and vibrating massage devices have similar energy signatures and, hence, cause similar bioeffects in treated tissues. We used laser fiber optic probe hydrophone (FOPH) measurements, high-speed imaging and x-ray film analysis to compare fundamental elements of the energy signatures of two rESWT devices (Swiss DolorClast; Electro Medical Systems, Nyon, Switzerland; D-Actor 200; Storz Medical, Tägerwillen, Switzerland) and a vibrating massage device (Vibracare; G5/General Physiotherapy, Inc., Earth City, MO, USA). To assert potential bioeffects of these treatment modalities we investigated the influence of rESWT and vibrating massage devices on locomotion ability of Caenorhabditis elegans (C. elegans) worms. FOPH measurements demonstrated that both rESWT devices generated acoustic waves with comparable pressure and energy flux density. Furthermore, both rESWT devices generated cavitation as evidenced by high-speed imaging and caused mechanical damage on the surface of x-ray film. The vibrating massage device did not show any of these characteristics. Moreover, locomotion ability of C. elegans was statistically significantly impaired after exposure to radial extracorporeal shock waves but was unaffected after exposure of worms to the vibrating massage device. The results of the present study indicate that both energy signature and bioeffects of rESWT devices are fundamentally different from those of vibrating massage devices. Prior ESWT studies have shown that tissues treated with sufficient quantities of acoustic sound waves undergo cavitation build-up, mechanotransduction, and ultimately, a biological alteration that "kick-starts" the healing response. Due to their different treatment indications and contra-indications rESWT devices cannot be equated to vibrating massage devices and should be used with due caution in clinical practice.

Stability of the tungsten diselenide and silicon carbide heterostructure against high energy proton exposure

NASA Astrophysics Data System (ADS)

Walker, Roger C.; Shi, Tan; Jariwala, Bhakti; Jovanovic, Igor; Robinson, Joshua A.

2017-10-01

Single layers of tungsten diselenide (WSe2) can be used to construct ultra-thin, high-performance electronics. Additionally, there has been considerable progress in controlled and direct growth of single layers on various substrates. Based on these results, high-quality WSe2-based devices that approach the limit of physical thickness are now possible. Such devices could be useful for space applications, but understanding how high-energy radiation impacts the properties of WSe2 and the WSe2/substrate interface has been lacking. In this work, we compare the stability against high energy proton radiation of WSe2 and silicon carbide (SiC) heterostructures generated by mechanical exfoliation of WSe2 flakes and by direct growth of WSe2 via metal-organic chemical vapor deposition (MOCVD). These two techniques produce WSe2/SiC heterostructures with distinct differences due to interface states generated during the MOCVD growth process. This difference carries over to differences in band alignment from interface states and the ultra-thin nature of the MOCVD-grown material. Both heterostructures are not susceptible to proton-induced charging up to a dose of 1016 protons/cm2, as measured via shifts in the binding energy of core shell electrons and a decrease in the valence band offset. Furthermore, the MOCVD-grown material is less affected by the proton exposure due to its ultra-thin nature and a greater interaction with the substrate. These combined effects show that the directly grown material is suitable for multi-year use in space, provided that high quality devices can be fabricated from it.

Using VAPEPS for noise control on Space Station Freedom

NASA Technical Reports Server (NTRS)

Badilla, Gloria; Bergen, Thomas; Scharton, Terry

1991-01-01

Noise environmental control is an important design consideration for Space Station Freedom (SSF), both for crew safety and productivity. Acoustic noise requirements are established to eliminate fatigue and potential hearing loss by crew members from long-term exposure and to facilitate speech communication. VAPEPS (VibroAcoustic Payload Environment Prediction System) is currently being applied to SSF for prediction of the on-orbit noise and vibration environments induced in the 50 to 10,000 Hz frequency range. Various sources such as fans, pumps, centrifuges, exercise equipment, and other mechanical devices are used in the analysis. The predictions will be used in design tradeoff studies and to provide confidence that requirements will be met. Preliminary predictions show that the required levels will be exceeded unless substantial noise control measures are incorporated in the SSF design. Predicted levels for an SSF design without acoustic control treatments exceed requirements by 25 dB in some one-third octave frequency bands.

Personal exposure assessment to particulate metals using a paper-based analytical device

NASA Astrophysics Data System (ADS)

Cate, David; Volckens, John; Henry, Charles

2013-03-01

The development of a paper-based analytical device (PAD) for assessing personal exposure to particulate metals will be presented. Human exposure to metal aerosols, such as those that occur in the mining, construction, and manufacturing industries, has a significant impact on the health of our workforce, costing an estimated $10B in the U.S and causing approximately 425,000 premature deaths world-wide each year. Occupational exposure to particulate metals affects millions of individuals in manufacturing, construction (welding, cutting, blasting), and transportation (combustion, utility maintenance, and repair services) industries. Despite these effects, individual workers are rarely assessed for their exposure to particulate metals, due mainly to the high cost and effort associated with personal exposure measurement. Current exposure assessment methods for particulate metals call for an 8-hour filter sample, after which time, the filter sample is transported to a laboratory and analyzed by inductively-coupled plasma (ICP). The time from sample collection to reporting is typically weeks and costs several hundred dollars per sample. To exacerbate the issue, method detection limits suffer because of sample dilution during digestion. The lack of sensitivity hampers task-based exposure assessment, for which sampling times may be tens of minutes. To address these problems, and as a first step towards using microfluidics for personal exposure assessment, we have developed PADs for measurement of Pb, Cd, Cr, Fe, Ni, and Cu in aerosolized particulate matter.

Phase holograms in PMMA with proximity effect correction

NASA Technical Reports Server (NTRS)

Maker, Paul D.; Muller, R. E.

1993-01-01

Complex computer generated phase holograms (CGPH's) have been fabricated in PMMA by partial e-beam exposure and subsequent partial development. The CGPH was encoded as a sequence of phase delay pixels and written by the JEOL JBX-5D2 E-beam lithography system, a different dose being assigned to each value of phase delay. Following carefully controlled partial development, the pattern appeared rendered in relief in the PMMA, which then acts as the phase-delay medium. The exposure dose was in the range 20-200 micro-C/sq cm, and very aggressive development in pure acetone led to low contrast. This enabled etch depth control to better than plus or minus lambda(sub vis)/60. That result was obtained by exposing isolated 50 micron square patches and measuring resist removal over the central area where the proximity effect dose was uniform and related only to the local exposure. For complex CGPH's with pixel size of the order of the e-beam proximity effect radius, the patterns must be corrected for the extra exposure caused by electrons scattered back up out of the substrate. This has been accomplished by deconvolving the two-dimensional dose deposition function with the desired dose pattern. The deposition function, which plays much the same role as an instrument response function, was carefully measured under the exact conditions used to expose the samples. The devices fabricated were designed with 16 equal phase steps per retardation cycle, were up to 1 cm square, and consisted of up to 100 million 0.3-2.0 micron square pixels. Data files were up to 500 MB long and exposure times ranged to tens of hours. A Fresnel phase lens was fabricated that had diffraction limited optical performance with better than 85 percent efficiency.

Cold Plasmas for Biofilm Control: Opportunities and Challenges.

PubMed

Gilmore, Brendan F; Flynn, Padrig B; O'Brien, Séamus; Hickok, Noreen; Freeman, Theresa; Bourke, Paula

2018-06-01

Bacterial biofilm infections account for a major proportion of chronic and medical device associated infections in humans, yet our ability to control them is compromised by their inherent tolerance to antimicrobial agents. Cold atmospheric plasma (CAP) represents a promising therapeutic option. CAP treatment of microbial biofilms represents the convergence of two complex phenomena: the production of a chemically diverse mixture of reactive species and intermediates, and their interaction with a heterogeneous 3D interface created by the biofilm extracellular polymeric matrix. Therefore, understanding these interactions and physiological responses to CAP exposure are central to effective management of infectious biofilms. We review the unique opportunities and challenges for translating CAP to the management of biofilms. Copyright © 2018. Published by Elsevier Ltd.

A noble technique a using force-sensing resistor for immobilization-device quality assurance: A feasibility study

NASA Astrophysics Data System (ADS)

Cho, Min-Seok; Kim, Tae-Ho; Kang, Seong-Hee; Kim, Dong-Su; Kim, Kyeong-Hyeon; Shin, Dong-Seok; Noh, Yu-Yun; Koo, Hyun-Jae; Cheon, Geum Seong; Suh, Tae Suk; Kim, Siyong

2016-03-01

Many studies have reported that a patient can move even when an immobilization device is used. Researchers have developed an immobilization-device quality-assurance (QA) system that evaluates the validity of immobilization devices. The QA system consists of force-sensing-resistor (FSR) sensor units, an electric circuit, a signal conditioning device, and a control personal computer (PC) with in-house software. The QA system is designed to measure the force between an immobilization device and a patient's skin by using the FSR sensor unit. This preliminary study aimed to evaluate the feasibility of using the QA system in radiation-exposure situations. When the FSR sensor unit was irradiated with a computed tomography (CT) beam and a treatment beam from a linear accelerator (LINAC), the stability of the output signal, the image artifact on the CT image, and changing the variation on the patient's dose were tested. The results of this study demonstrate that this system is promising in that it performed within the error range (signal variation on CT beam < 0.30 kPa, root-mean-square error (RMSE) of the two CT images according to presence or absence of the FSR sensor unit < 15 HU, signal variation on the treatment beam < 0.15 kPa, and dose difference between the presence and the absence of the FSR sensor unit < 0.02%). Based on the obtained results, we will volunteer tests to investigate the clinical feasibility of the QA system.

Measuring ionizing radiation with a mobile device

NASA Astrophysics Data System (ADS)

Michelsburg, Matthias; Fehrenbach, Thomas; Puente León, Fernando

2012-02-01

In cases of nuclear disasters it is desirable to know one's personal exposure to radioactivity and the related health risk. Usually, Geiger-Mueller tubes are used to assess the situation. Equipping everyone with such a device in a short period of time is very expensive. We propose a method to detect ionizing radiation using the integrated camera of a mobile consumer device, e.g., a cell phone. In emergency cases, millions of existing mobile devices could then be used to monitor the exposure of its owners. In combination with internet access and GPS, measured data can be collected by a central server to get an overview of the situation. During a measurement, the CMOS sensor of a mobile device is shielded from surrounding light by an attachment in front of the lens or an internal shutter. The high-energy radiation produces free electrons on the sensor chip resulting in an image signal. By image analysis by means of the mobile device, signal components due to incident ionizing radiation are separated from the sensor noise. With radioactive sources present significant increases in detected pixels can be seen. Furthermore, the cell phone application can make a preliminary estimate on the collected dose of an individual and the associated health risks.

Mobile work: Ergonomics in a rapidly changing work environment.

PubMed

Honan, Meg

2015-01-01

Places of work have been completely transformed by innovations in mobile work tools and ever-present access to internet data. This article characterizes use patterns and provides preliminary considerations for productive and comfortable use of common mobile devices. Two surveys described trends in mobile work. In the first, ergonomics professionals who oversee programs reported common mobile devices, their users and what data is accessed. The second, an end user survey, explored common activities performed on mobile devices, duration of use and locations where mobile work is common. The survey results provide a baseline data point for the status of mobile work in early 2014. Research indicates that additional risks have been introduced to the neck, thumbs and hands when using mobile devices. Possible trends regarding device use and work locations emerge. Intervention studies provide some direction for the practitioner. Practical strategies are outlined to reduce exposure intensity and duration. Contemporary mobile work presents tremendous change and opportunity for ergonomists and researchers to keep pace with fitting the changing models of work to the person. Continued research is needed on current mobile device use patterns to better understand ergonomic risk exposure in this rapidly changing realm.

Silk-polypyrrole biocompatible actuator performance under biologically relevant conditions

NASA Astrophysics Data System (ADS)

Hagler, Jo'elen; Peterson, Ben; Murphy, Amanda; Leger, Janelle

Biocompatible actuators that are capable of controlled movement and can function under biologically relevant conditions are of significant interest in biomedical fields. Previously, we have demonstrated that a composite material of silk biopolymer and the conducting polymer polypyrrole (PPy) can be formed into a bilayer device that can bend under applied voltage. Further, these silk-PPy composites can generate forces comparable to human muscle (>0.1 MPa) making them ideal candidates for interfacing with biological tissues. Here silk-PPy composite films are tested for performance under biologically relevant conditions including exposure to a complex protein serum and biologically relevant temperatures. Free-end bending actuation performance, current response, force generation and, mass degradation were investigated . Preliminary results show that when exposed to proteins and biologically relevant temperatures, these silk-PPy composites show minimal degradation and are able to generate forces and conduct currents comparable to devices tested under standard conditions. NSF.

Defect generation in electronic devices under plasma exposure: Plasma-induced damage

NASA Astrophysics Data System (ADS)

Eriguchi, Koji

2017-06-01

The increasing demand for higher performance of ULSI circuits requires aggressive shrinkage of device feature sizes in accordance with Moore’s law. Plasma processing plays an important role in achieving fine patterns with anisotropic features in metal-oxide-semiconductor field-effect transistors (MOSFETs). This article comprehensively addresses the negative aspect of plasma processing — plasma-induced damage (PID). PID naturally not only modifies the surface morphology of materials but also degrades the performance and reliability of MOSFETs as a result of defect generation in the materials. Three key mechanisms of PID, i.e., physical, electrical, and photon-irradiation interactions, are overviewed in terms of modeling, characterization techniques, and experimental evidence reported so far. In addition, some of the emerging topics — control of parameter variability in ULSI circuits caused by PID and recovery of PID — are discussed as future perspectives.

Electronic Media Exposure and Use among Toddlers.

PubMed

Chang, Hyoung Yoon; Park, Eun-Jin; Yoo, Hee-Jeong; Lee, Jee Won; Shin, Yunmi

2018-05-24

These days, young children are exposed to a wide range of smart devices and their usage of smart devices is rapidly increasing worldwide. However, the use of smart devices by young children has not been studied in detail yet because smart device is relatively recent. The purpose of this study was to investigate the exposure status of smart devices among 2-5 years old children in Korea. Four hundred parents of 2- to 5-year-old children were invited to enroll. Data on demographic information and the frequency of media use, time of media use, age at first use of media was self-reported. Among 390 toddlers, 39.3% watched TV almost every day, while 12.0% of children used smartphone on a daily basis. During weekdays, 48% of the children watched TV for over an hour. On weekends, 63.1% of the children watched TV for over an hour. On weekends, 23.4% of children use their smartphones for over an hour. Children using smartphones before 24 months of age were 31.3%. Research has shown that TV and smartphones are the most popular digital devices used by toddlers. Most toddlers began using smart devices at 12-24 months. This study provides comprehensive information on children's contemporary use of media.

A Supramolecular Nanofiber-Based Passive Memory Device for Remembering Past Humidity.

PubMed

Mogera, Umesha; Gedda, Murali; George, Subi J; Kulkarni, Giridhar U

2017-09-20

Memorizing the magnitude of a physical parameter such as relative humidity in a consignment may be useful for maintaining recommended conditions over a period of time. In relation to cost and energy considerations, it is important that the memorizing device works in the unpowered passive state. In this article, we report the fabrication of a humidity-responsive device that can memorize the humidity condition it had experienced while being unpowered. The device makes use of supramolecular nanofibers obtained from the self-assembly of donor-acceptor (D-A) molecules, coronene tetracarboxylate salt (CS) and dodecyl methyl viologen (DMV), respectively, from aqueous medium. The fibers, while being highly sensitive to humidity, tend to develop electrically induced disorder under constant voltage, leading to increased resistance with time. The conducting state can be regained via self-assembly by exposing the device to humidity in the absence of applied voltage, the extent of recovery depending on the magnitude of the humidity applied under no bias. This nature of the fibers has been exploited in reading the humidity memory state, which interestingly is independent of the lapsed time since the humidity exposure as well as the duration of exposure. Importantly, the device is capable of differentiating the profiles of varying humidity conditions from its memory. The device finds use in applications requiring stringent condition monitoring.

Low-Temperature Solution-Processed ZnSe Electron Transport Layer for Efficient Planar Perovskite Solar Cells with Negligible Hysteresis and Improved Photostability.

PubMed

Li, Xin; Yang, Junyou; Jiang, Qinghui; Lai, Hui; Li, Shuiping; Xin, Jiwu; Chu, Weijing; Hou, Jingdi

2018-05-15

For a typical perovskite solar cell (PKSC), the electron transport layer (ETL) has a great effect on device performance and stability. Herein, we manifest that low-temperature solution-processed ZnSe can be used as a potential ETL for PKSCs. Our optimized device with ZnSe ETL has achieved a high power conversion efficiency (PCE) of 17.78% with negligible hysteresis, compared with the TiO 2 based cell (13.76%). This enhanced photovoltaic performance is attributed to the suitable band alignment, high electron mobility, and reduced charge accumulation at the interface of ETL/perovskite. Encouraging results were obtained when the thin layer of ZnSe cooperated with TiO 2 . It shows that the device based on the TiO 2 /ZnSe ETL with cascade conduction band level can effectively reduce the interfacial charge recombination and promote carrier transfer with the champion PCE of 18.57%. In addition, the ZnSe-based device exhibits a better photostability than the control device due to the greater ultraviolet (UV) light harvesting of the ZnSe layer, which can efficiently prevent the perovskite film from intense UV-light exposure to avoid associated degradation. Consequently, our results present that a promising ETL can be a potential candidate of the n-type ETL for commercialization of efficient and photostable PKSCs.

Bipolar Sealer Devices Used in Posterior Spinal Fusion for Neuromuscular Scoliosis Reduce Blood Loss and Transfusion Requirements.

PubMed

Hardesty, Christina K; Gordon, Zachary L; Poe-Kochert, Connie; Son-Hing, Jochen P; Thompson, George H

2018-02-01

Reducing perioperative blood loss and the need for transfusions in patients undergoing spinal surgery is especially important for those with neuromuscular disorders. These patients require extensive spino-pelvic exposure and are often medically fragile. We have used Amicar to decrease blood loss since 2001. As an effort to further reduce blood loss and transfusions, we use a bipolar sealer device (Aquamantys) as an adjunct to electrocautery. We present the results of our first 64 neuromuscular patients to show the efficacy of the device. Using a prospectively maintained database we reviewed the operative time, estimated perioperative blood loss, cell saver use, and intraoperative and postoperative transfusion rate in patients who underwent posterior spinal fusion for neuromuscular scoliosis. Sixty-four patients were identified who fit these criteria since the use of the bipolar sealer device was instituted.We compared these patients with a control group of the preceding 65 patients in whom this device was not used for hemostasis. All patients, including those in the study group, received Amicar (infusion of 100 mg/kg over 15 to 20 min, then 10 mg/kg/h throughout the remainder of the procedure). The surgical technique did not differ between the 2 groups. Baseline characteristics between the 2 groups were similar except for the number of patients having an all-screw construct which was larger in the investigational group (25% vs. 8%, P=0.03). There were no significant differences in operative time or duration of hospital stay. Intraoperative blood loss was lower in the study group (741 mL) as compared with the control group (1052 mL, P=0.003). Total perioperative blood loss, however, showed no significant difference. Thirty-five (55%) patients in the study group and 50 (77%) patients in the control group required additional intraoperative or postoperative transfusions (P=0.01). The number of packed red cell units transfused per patient was 0.81 in the study group and 1.57 in the control group (P=0.001). Although the intraoperative cell saver transfusion was same, the total blood volume transfused, which includes cell saver and any other transfusions, was significantly lower in the study group, 425 mL versus 671 mL (P=0.002). Use of a bipolar sealer device in posterior spinal fusion for neuromuscular scoliosis significantly reduced intraoperative blood loss and transfusion rate when compared with a control group in this retrospective review. Level III-retrospective comparative study.

Microfluidics meets metabolomics to reveal the impact of Campylobacter jejuni infection on biochemical pathways.

PubMed

Mortensen, Ninell P; Mercier, Kelly A; McRitchie, Susan; Cavallo, Tammy B; Pathmasiri, Wimal; Stewart, Delisha; Sumner, Susan J

2016-06-01

Microfluidic devices that are currently being used in pharmaceutical research also have a significant potential for utilization in investigating exposure to infectious agents. We have established a microfluidic device cultured with Caco-2 cells, and utilized metabolomics to investigate the biochemical responses to the bacterial pathogen Campylobacter jejuni. In the microfluidic devices, Caco-2 cells polarize at day 5, are uniform, have defined brush borders and tight junctions, and form a mucus layer. Metabolomics analysis of cell culture media collected from both Caco-2 cell culture systems demonstrated a more metabolic homogenous biochemical profile in the media collected from microfluidic devices, compared with media collected from transwells. GeneGo pathway mapping indicated that aminoacyl-tRNA biosynthesis was perturbed by fluid flow, suggesting that fluid dynamics and shear stress impacts the cells translational quality control. Both microfluidic device and transwell culturing systems were used to investigate the impact of Campylobacter jejuni infection on biochemical processes. Caco-2 cells cultured in either system were infected at day 5 with C. jejuni 81-176 for 48 h. Metabolomics analysis clearly differentiated C. jejuni 81-176 infected and non-infected medias collected from the microfluidic devices, and demonstrated that C. jejuni 81-176 infection in microfluidic devices impacts branched-chain amino acid metabolism, glycolysis, and gluconeogenesis. In contrast, no distinction was seen in the biochemical profiles of infected versus non-infected media collected from cells cultured in transwells. Microfluidic culturing conditions demonstrated a more metabolically homogenous cell population, and present the opportunity for studying host-pathogen interactions for extended periods of time.

Microfluidics Meets Metabolomics to Reveal the Impact of Campylobacter jejuni Infection on Biochemical Pathways

PubMed Central

Mortensen, Ninell P.; Mercier, Kelly A.; McRitchie, Susan; Cavallo, Tammy B.; Pathmasiri, Wimal; Stewart, Delisha; Sumner, Susan J.

2016-01-01

Microfluidic devices that are currently being used in pharmaceutical research also have a significant potential for utilization in investigating exposure to infectious agents. We have established a microfluidic device cultured with Caco-2 cells, and utilized metabolomics to investigate the biochemical responses to the bacterial pathogen Campylobacter jejuni. In the microfluidic devices, Caco-2 cells polarize at day 5, are uniform, have defined brush borders and tight junctions, and form a mucus layer. Metabolomics analysis of cell culture media collected from both Caco-2 cell culture systems demonstrated a more metabolic homogenous biochemical profile in the media collected from microfluidic devices, compared with media collected from transwells. GeneGo pathway mapping indicated that aminoacyl-tRNA biosynthesis was perturbed by fluid flow, suggesting that fluid dynamics and shear stress impacts the cells translational quality control. Both microfluidic device and transwell culturing systems were used to investigate the impact of Campylobacter jejuni infection on biochemical processes. Caco-2 cells cultured in either system were infected at day 5 with C. jejuni 81-176 for 48 hours. Metabolomics analysis clearly differentiated C. jejuni 81-176 infected and non-infected medias collected from the microfluidic devices, and demonstrated that C. jejuni 81-176 infection in microfluidic devices impacts branched-chain amino acid metabolism, glycolysis, and gluconeogenesis. In contrast, no distinction was seen in the biochemical profiles of infected versus non-infected media collected from cells cultured in transwells. Microfluidic culturing conditions demonstrated a more metabolically homogenous cell population, and present the opportunity for studying host-pathogen interactions for extended periods of time. PMID:27231016

Patterning control strategies for minimum edge placement error in logic devices

NASA Astrophysics Data System (ADS)

Mulkens, Jan; Hanna, Michael; Slachter, Bram; Tel, Wim; Kubis, Michael; Maslow, Mark; Spence, Chris; Timoshkov, Vadim

2017-03-01

In this paper we discuss the edge placement error (EPE) for multi-patterning semiconductor manufacturing. In a multi-patterning scheme the creation of the final pattern is the result of a sequence of lithography and etching steps, and consequently the contour of the final pattern contains error sources of the different process steps. We describe the fidelity of the final pattern in terms of EPE, which is defined as the relative displacement of the edges of two features from their intended target position. We discuss our holistic patterning optimization approach to understand and minimize the EPE of the final pattern. As an experimental test vehicle we use the 7-nm logic device patterning process flow as developed by IMEC. This patterning process is based on Self-Aligned-Quadruple-Patterning (SAQP) using ArF lithography, combined with line cut exposures using EUV lithography. The computational metrology method to determine EPE is explained. It will be shown that ArF to EUV overlay, CDU from the individual process steps, and local CD and placement of the individual pattern features, are the important contributors. Based on the error budget, we developed an optimization strategy for each individual step and for the final pattern. Solutions include overlay and CD metrology based on angle resolved scatterometry, scanner actuator control to enable high order overlay corrections and computational lithography optimization to minimize imaging induced pattern placement errors of devices and metrology targets.

Semiconductor diode laser device adjuvanting intradermal vaccine

PubMed Central

Kimizuka, Yoshifumi; Callahan, John J.; Huang, Zilong; Morse, Kaitlyn; Katagiri, Wataru; Shigeta, Ayako; Bronson, Roderick; Takeuchi, Shu; Shimaoka, Yusuke; Chan, Megan P. K.; Zeng, Yang; Li, Binghao; Chen, Huabiao; Tan, Rhea Y. Y.; Dwyer, Conor; Mulley, Tyler; Leblanc, Pierre; Goudie, Calum; Gelfand, Jeffrey; Tsukada, Kosuke; Brauns, Timothy; Poznansky, Mark C.; Bean, David; Kashiwagi, Satoshi

2017-01-01

A brief exposure of skin to a low-power, non-tissue damaging laser light has been demonstrated to augment immune responses to intradermal vaccination. Both preclinical and clinical studies show that this approach is simple, effective, safe and well tolerated compared to standard chemical or biological adjuvants. Until now, these laser exposures have been performed using a diode-pumped solid-state laser (DPSSL) devices, which are expensive and require labor-intensive maintenance and special training. Development of an inexpensive, easy-to-use and small device would form an important step in translating this technology toward clinical application Here we report that we have established a handheld, near-infrared (NIR) laser device using semiconductor diodes emitting either 1061, 1258, or 1301 nm light that costs less than $4,000, and that this device replicates the adjuvant effect of a DPSSL system in a mouse model of influenza vaccination. Our results also indicate that a broader range of NIR laser wavelengths possess the ability to enhance vaccine immune responses, allowing engineering options for the device design. This small, low-cost device establishes the feasibility of using a laser adjuvant approach for mass-vaccination programs in a clinical setting, opens the door for broader testing of this technology with a variety of vaccines and forms the foundation for development of devices ready for use in the clinic. PMID:28365253

Semiconductor diode laser device adjuvanting intradermal vaccine.

PubMed

Kimizuka, Yoshifumi; Callahan, John J; Huang, Zilong; Morse, Kaitlyn; Katagiri, Wataru; Shigeta, Ayako; Bronson, Roderick; Takeuchi, Shu; Shimaoka, Yusuke; Chan, Megan P K; Zeng, Yang; Li, Binghao; Chen, Huabiao; Tan, Rhea Y Y; Dwyer, Conor; Mulley, Tyler; Leblanc, Pierre; Goudie, Calum; Gelfand, Jeffrey; Tsukada, Kosuke; Brauns, Timothy; Poznansky, Mark C; Bean, David; Kashiwagi, Satoshi

2017-04-25

A brief exposure of skin to a low-power, non-tissue damaging laser light has been demonstrated to augment immune responses to intradermal vaccination. Both preclinical and clinical studies show that this approach is simple, effective, safe and well tolerated compared to standard chemical or biological adjuvants. Until now, these laser exposures have been performed using a diode-pumped solid-state laser (DPSSL) devices, which are expensive and require labor-intensive maintenance and special training. Development of an inexpensive, easy-to-use and small device would form an important step in translating this technology toward clinical application. Here we report that we have established a handheld, near-infrared (NIR) laser device using semiconductor diodes emitting either 1061, 1258, or 1301nm light that costs less than $4000, and that this device replicates the adjuvant effect of a DPSSL system in a mouse model of influenza vaccination. Our results also indicate that a broader range of NIR laser wavelengths possess the ability to enhance vaccine immune responses, allowing engineering options for the device design. This small, low-cost device establishes the feasibility of using a laser adjuvant approach for mass-vaccination programs in a clinical setting, opens the door for broader testing of this technology with a variety of vaccines and forms the foundation for development of devices ready for use in the clinic. Copyright © 2017 Elsevier Ltd. All rights reserved.

Residual Isocyanates in Medical Devices and Products: A Qualitative and Quantitative Assessment

PubMed Central

Franklin, Gillian; Harari, Homero; Ahsan, Samavi; Bello, Dhimiter; Sterling, David A.; Nedrelow, Jonathan; Raynaud, Scott; Biswas, Swati; Liu, Youcheng

2016-01-01

We conducted a pilot qualitative and quantitative assessment of residual isocyanates and their potential initial exposures in neonates, as little is known about their contact effect. After a neonatal intensive care unit (NICU) stockroom inventory, polyurethane (PU) and PU foam (PUF) devices and products were qualitatively evaluated for residual isocyanates using Surface SWYPE™. Those containing isocyanates were quantitatively tested for methylene diphenyl diisocyanate (MDI) species, using UPLC-UV-MS/MS method. Ten of 37 products and devices tested, indicated both free and bound residual surface isocyanates; PU/PUF pieces contained aromatic isocyanates; one product contained aliphatic isocyanates. Overall, quantified mean MDI concentrations were low (4,4′-MDI = 0.52 to 140.1 pg/mg) and (2,4′-MDI = 0.01 to 4.48 pg/mg). The 4,4′-MDI species had the highest measured concentration (280 pg/mg). Commonly used medical devices/products contain low, but measurable concentrations of residual isocyanates. Quantifying other isocyanate species and neonatal skin exposure to isocyanates from these devices and products requires further investigation. PMID:27773989

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

Code of Federal Regulations, 2013 CFR

2013-10-01

... Electromagnetic Fields, 3 kHz to 300 GHz,” ANSI/IEEE C95.1-1992, Copyright 1992 by the Institute of Electrical and... Exposure Criteria for Radiofrequency Electromagnetic Fields,” NCRP Report No. 86, Section 17.4.5. Copyright...

Use of nonthermal blue (405- to 420-nm) and near-infrared light (850- to 900-nm) dual-wavelength system in combination with glycolic acid peels and topical vitamin C for skin photorejuvenation.

PubMed

Fournier, Nathalie; Fritz, Klaus; Mordon, Serge

2006-09-01

A major cause of skin aging is a chronic microinflammation created by environmental conditions and ultraviolet exposures. The hand-free application on the skin of a new intense light combining a narrowband blue-light (405- to 420-nm) antiinflammatory emission and a near-infrared (850- to 890-nm) emission inducing self-defense mechanisms provides a new component to photorejuvenation and antiaging treatment protocols. An innovative skin rejuvenation schedule is presented in this study. It includes skin exposure to the light, with concomitant glycolic peels and daily vitamin C cream regimen for group A and only topical vitamin C cream and glycolic peels for control group B. Results show a significant improvement on pore size, rhytids, and radiance in group A. Conversely no improvement is noticed in group B except for a brief increase of skin radiance. Mechanisms of action of that specific light source are discussed. The exposure to this device can clinically enhance conventional antiaging protocols in skin rejuvenation.

Single-expose patterning development for EUV lithography

NASA Astrophysics Data System (ADS)

De Silva, Anuja; Petrillo, Karen; Meli, Luciana; Shearer, Jeffrey C.; Beique, Genevieve; Sun, Lei; Seshadri, Indira; Oh, Taehwan; Han, Seulgi; Saulnier, Nicole; Lee, Joe; Arnold, John C.; Hamieh, Bassem; Felix, Nelson M.; Furukawa, Tsuyoshi; Singh, Lovejeet; Ayothi, Ramakrishnan

2017-03-01

Initial readiness of EUV (extreme ultraviolet) patterning was demonstrated in 2016 with IBM Alliance's 7nm device technology. The focus has now shifted to driving the 'effective' k1 factor and enabling the second generation of EUV patterning. With the substantial cost of EUV exposure there is significant interest in extending the capability to do single exposure patterning with EUV. To enable this, emphasis must be placed on the aspect ratios, adhesion, defectivity reduction, etch selectivity, and imaging control of the whole patterning process. Innovations in resist materials and processes must be included to realize the full entitlement of EUV lithography at 0.33NA. In addition, enhancements in the patterning process to enable good defectivity, lithographic process window, and post etch pattern fidelity are also required. Through this work, the fundamental material challenges in driving down the effective k1 factor will be highlighted.

Pellicle transmission uniformity requirements

NASA Astrophysics Data System (ADS)

Brown, Thomas L.; Ito, Kunihiro

1998-12-01

Controlling critical dimensions of devices is a constant battle for the photolithography engineer. Current DUV lithographic process exposure latitude is typically 12 to 15% of the total dose. A third of this exposure latitude budget may be used up by a variable related to masking that has not previously received much attention. The emphasis on pellicle transmission has been focused on increasing the average transmission. Much less, attention has been paid to transmission uniformity. This paper explores the total demand on the photospeed latitude budget, the causes of pellicle transmission nonuniformity and examines reasonable expectations for pellicle performance. Modeling is used to examine how the two primary errors in pellicle manufacturing contribute to nonuniformity in transmission. World-class pellicle transmission uniformity standards are discussed and a comparison made between specifications of other components in the photolithographic process. Specifications for other materials or parameters are used as benchmarks to develop a proposed industry standard for pellicle transmission uniformity.

Notes from the field: calls to poison centers for exposures to electronic cigarettes--United States, September 2010-February 2014.

PubMed

Chatham-Stephens, Kevin; Law, Royal; Taylor, Ethel; Melstrom, Paul; Bunnell, Rebecca; Wang, Baoguang; Apelberg, Benjamin; Schier, Joshua G

2014-04-04

Electronic nicotine delivery devices such as electronic cigarettes (e-cigarettes) are battery-powered devices that deliver nicotine, flavorings (e.g., fruit, mint, and chocolate), and other chemicals via an inhaled aerosol. E-cigarettes that are marketed without a therapeutic claim by the product manufacturer are currently not regulated by the Food and Drug Administration (FDA). In many states, there are no restrictions on the sale of e-cigarettes to minors. Although e-cigarette use is increasing among U.S. adolescents and adults, its overall impact on public health remains unclear. One area of concern is the potential of e-cigarettes to cause acute nicotine toxicity. To assess the frequency of exposures to e-cigarettes and characterize the reported adverse health effects associated with e-cigarettes, CDC analyzed data on calls to U.S. poison centers (PCs) about human exposures to e-cigarettes (exposure calls) for the period September 2010 (when new, unique codes were added specifically for capturing e-cigarette calls) through February 2014. To provide a comparison to a conventional product with known toxicity, the number and characteristics of e-cigarette exposure calls were compared with those of conventional tobacco cigarette exposure calls.

Light-induced retinal damage using different light sources, protocols and rat strains reveals LED phototoxicity.

PubMed

Krigel, A; Berdugo, M; Picard, E; Levy-Boukris, R; Jaadane, I; Jonet, L; Dernigoghossian, M; Andrieu-Soler, C; Torriglia, A; Behar-Cohen, F

2016-12-17

To save energy, the European directives from the Eco-design of Energy Using Products (2005/32/CE) have recommended the replacement of incandescent lamps by more economic devices such as Light Emitting Diodes (LEDs). However, the emission spectrum of these devices is enriched in blue radiations, known to be potentially dangerous to the retina. Recent studies showed that light exposure contributes to the onset of early stages of age-related macular degeneration (AMD). Here, we investigate, in albinos and pigmented rats, the effects of different exposure protocols. Twenty-four hours exposure at high luminance was compared to a cyclic (dark/light) exposure at domestic levels for 1week and 1month, using different LEDs (Cold-white, blue and green), as well as fluorocompact bulbs and fluorescent tubes. The data suggest that the blue component of the white-LED may cause retinal toxicity at occupational domestic illuminance and not only in extreme experimental conditions, as previously reported. It is important to note that the current regulations and standards have been established on the basis of acute light exposure and do not take into account the effects of repeated exposure. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

76 FR 54156 - National Standards for Traffic Control Devices; the Manual on Uniform Traffic Control Devices for...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-31

... traffic control device design, location, or operation that have made some existing devices in the field...-2010-0159] RIN 2125-AF43 National Standards for Traffic Control Devices; the Manual on Uniform Traffic Control Devices for Streets and Highways; Revision AGENCY: Federal Highway Administration (FHWA...

[Occupational exposure of physical therapists to electric and magnetic fields and the efficacy of Faraday cages].

PubMed

Messias, Iracimara de Anchieta; Okuno, Emico; Colacioppo, Sérgio

2011-10-01

Measure physical therapists' exposure to the electric and magnetic fields produced by 17 shortwave diathermy devices in physical therapy clinics in the city of Presidente Prudente, São Paulo State, Brazil. Compare the observed values with the exposure levels recommended by the International Commission on Non-ionizing Radiation Protection (ICNIRP). Observe the efficacy of Faraday cages as a means of protecting physical therapists from exposure to oscillating electric and magnetic fields. Electric and magnetic field measurements were taken at four points during actual physical therapy sessions: in proximity to the operator's pelvis and head, the devices' electrical cables, and the electrodes. The measuring equipment was a Wandel & Goltermann EMR-200. The values obtained in proximity to the electrodes and cables were 10 to 30 times higher than ICNIRP's recommended occupational reference levels. In the shortwave diathermy treatment rooms with Faraday cages, the fields were even higher than in treatment rooms not so equipped-principally the magnetic field, where the values were more than 100 times higher than the ICNIRP exposure limit. The electric and magnetic field intensities obtained in this study are generally above the exposure levels recommend in ICNIRP standards. It was also observed that the Faraday cage offers physical therapists no protection, and instead, increases their level of exposure.

Impact of closed-system drug transfer device on exposure of environment and healthcare provider to cyclophosphamide in Japanese hospital.

PubMed

Miyake, Tomohiro; Iwamoto, Takuya; Tanimura, Manabu; Okuda, Masahiro

2013-12-01

In spite of current recommended safe handling procedures, the potential for the exposure of healthcare providers to hazardous drugs exists in the workplace. A reliance on biological safety cabinets to provide total protection against the exposure to hazardous drugs is insufficient. Preventing workplace contamination is the best strategy to minimize cytotoxic drug exposure in healthcare providers. This study was conducted to compare surface contamination and personnel exposure to cyclophosphamide before and after the implementation of a closed-system drug transfer device, PhaSeal, under the influence of cleaning according to the Japanese guidelines. Personnel exposure was evaluated by collecting 24 h urine samples from 4 pharmacists. Surface contamination was assessed by the wiping test. Four of 6 wipe samples collected before PhaSeal indicated a detectable level of cyclophosphamide. About 7 months after the initiation of PhaSeal, only one of 6 wipe samples indicated a detectable level of cyclophosphamide. Although all 4 employees who provided urine samples had positive results for the urinary excretion of cyclophosphamide before PhaSeal, these levels returned to minimal levels in 2 pharmacists after PhaSeal. In combination with the biological safety cabinet and cleaning according to the Japanese guidelines, PhaSeal further reduces surface contamination and healthcare providers exposure to cyclophosphamide to almost undetectable levels.

Optically Defined Multifunctional Patterning of Photosensitive Thin-Film Silica Mesophases

NASA Astrophysics Data System (ADS)

Doshi, Dhaval A.; Huesing, Nicola K.; Lu, Mengcheng; Fan, Hongyou; Lu, Yunfeng; Simmons-Potter, Kelly; Potter, B. G.; Hurd, Alan J.; Brinker, C. Jeffrey

2000-10-01

Photosensitive films incorporating molecular photoacid generators compartmentalized within a silica-surfactant mesophase were prepared by an evaporation-induced self-assembly process. Ultraviolet exposure promoted localized acid-catalyzed siloxane condensation, which can be used for selective etching of unexposed regions; for ``gray-scale'' patterning of refractive index, pore size, surface area, and wetting behavior; and for optically defining a mesophase transformation (from hexagonal to tetragonal) within the film. The ability to optically define and continuously control both structure and function on the macro- and mesoscales is of interest for sensor arrays, nanoreactors, photonic and fluidic devices, and low-dielectric-constant films.

A cost effective and high fidelity fluoroscopy simulator using the Image-Guided Surgery Toolkit (IGSTK)

NASA Astrophysics Data System (ADS)

Gong, Ren Hui; Jenkins, Brad; Sze, Raymond W.; Yaniv, Ziv

2014-03-01

The skills required for obtaining informative x-ray fluoroscopy images are currently acquired while trainees provide clinical care. As a consequence, trainees and patients are exposed to higher doses of radiation. Use of simulation has the potential to reduce this radiation exposure by enabling trainees to improve their skills in a safe environment prior to treating patients. We describe a low cost, high fidelity, fluoroscopy simulation system. Our system enables operators to practice their skills using the clinical device and simulated x-rays of a virtual patient. The patient is represented using a set of temporal Computed Tomography (CT) images, corresponding to the underlying dynamic processes. Simulated x-ray images, digitally reconstructed radiographs (DRRs), are generated from the CTs using ray-casting with customizable machine specific imaging parameters. To establish the spatial relationship between the CT and the fluoroscopy device, the CT is virtually attached to a patient phantom and a web camera is used to track the phantom's pose. The camera is mounted on the fluoroscope's intensifier and the relationship between it and the x-ray source is obtained via calibration. To control image acquisition the operator moves the fluoroscope as in normal operation mode. Control of zoom, collimation and image save is done using a keypad mounted alongside the device's control panel. Implementation is based on the Image-Guided Surgery Toolkit (IGSTK), and the use of the graphics processing unit (GPU) for accelerated image generation. Our system was evaluated by 11 clinicians and was found to be sufficiently realistic for training purposes.

Inhibition of Biofilm Formation by Esomeprazole in Pseudomonas aeruginosa and Staphylococcus aureus

PubMed Central

Singh, Vandana; Arora, Vaneet; Alam, M. Jahangir

2012-01-01

Staphylococcus aureus and Pseudomonas aeruginosa are common nosocomial pathogens responsible for biofilm-associated infections. Proton pump inhibitors (PPI), such as esomeprazole, may have novel antimicrobial properties. The objective of this study was to assess whether esomeprazole prevents sessile bacterial growth and biofilm formation and whether it may have synergistic killing effects with standard antibiotics. The antibiofilm activity of esomeprazole at 0.25 mM was tested against two strains each of S. aureus and P. aeruginosa. Bacterial biofilms were prepared using a commercially available 96-peg-plate Calgary biofilm device. Sessile bacterial CFU counts and biomass were assessed during 72 hours of esomeprazole exposure. The killing activities after an additional 24 hours of vancomycin (against S. aureus) and meropenem (against P. aeruginosa) treatment with or without preexposure to esomeprazole were also assessed by CFU and biomass analyses. P. aeruginosa and S. aureus strains exposed to esomeprazole displayed decreased sessile bacterial growth and biomass (P < 0.001, each parameter). After 72 h of exposure, there was a 1-log10 decrease in the CFU/ml of esomeprazole-exposed P. aeruginosa and S. aureus strains compared to controls (P < 0.001). After 72 h of exposure, measured absorbance was 100% greater in P. aeruginosa control strains than in esomeprazole-exposed strains (P < 0.001). Increased killing and decreased biomass were observed for esomeprazole-treated bacteria compared to untreated controls exposed to conventional antibiotics (P < 0.001, each parameter). Reduced biofilm growth after 24 h was visibly apparent by light micrographs for P. aeruginosa and S. aureus isolates exposed to esomeprazole compared to untreated controls. In conclusion, esomeprazole demonstrated an antibiofilm effect against biofilm-producing S. aureus and P. aeruginosa. PMID:22664967

Sequestration of priority pollutant PAHs from sediment pore water employing semipermeable membrane devices.

PubMed

Williamson, Kelly S; Petty, Jimmie D; Huckins, James N; Lebo, Jon A; Kaiser, Edwin M

2002-11-01

Semipermeable membrane devices (SPMDs) were employed to sample sediment pore water in static exposure studies under controlled laboratory conditions using (control pond and formulated) sediments fortified with 15 priority pollutant polycyclic aromatic hydrocarbons (PPPAHs). The sediment fortification level of 750 ng/g was selected on the basis of what might be detected in a sediment sample from a contaminated area. The sampling interval consisted of 0, 4, 7, 14, and 28 days for each study. The analytical methodologies, as well as the extraction and sample cleanup procedures used in the isolation, characterization, and quantitation of 15 PPPAHs at different fortification levels in SPMDs, water, and sediment were reported previously (Williamson, M.S. Thesis, University of Missouri-Columbia, USA; Williamson et al., Chemosphere (This issue--PII: S0045-6535(02)00394-6)) and used for this project. Average (mean) extraction recoveries for each PPPAH congener in each matrix are reported and discussed. No procedural blank extracts (controls) were found to contain any PPPAH residues above the method quantitation limit, therefore, no matrix interferences were detected. The focus of this publication is to demonstrate the ability to sequester environmental contaminants, specifically PPPAHs, from sediment pore water using SPMDs and two different types of fortified sediment.

Sequestration of priority pollutant PAHs from sediment pore water employing semipermeable membrane devices

USGS Publications Warehouse

Williamson, K.S.; Petty, J.D.; Huckins, J.N.; Lebo, J.A.; Kaiser, E.M.

2002-01-01

Semipermeable membrane devices (SPMDs) were employed to sample sediment pore water in static exposure studies under controlled laboratory conditions using (control pond and formulated) sediments fortified with 15 priority pollutant polycyclic aromatic hydrocarbons (PPPAHs). The sediment fortification level of 750 ng/g was selected on the basis of what might be detected in a sediment sample from a contaminated area. The sampling interval consisted of 0, 4, 7, 14, and 28 days for each study. The analytical methodologies, as well as the extraction and sample cleanup procedures used in the isolation, characterization, and quantitation of 15 PPPAHs at different fortification levels in SPMDs, water, and sediment were reported previously (Williamson, M.S. Thesis, University of Missouri - Columbia, USA; Williamson et al., Chemosphere (This issue - PII: S0045-6535(02)00394-6)) and used for this project. Average (mean) extraction recoveries for each PPPAH congener in each matrix are reported and discussed. No procedural blank extracts (controls) were found to contain any PPPAH residues above the method quantitation limit, therefore, no matrix interferences were detected. The focus of this publication is to demonstrate the ability to sequester environmental contaminants, specifically PPPAHs, from sediment pore water using SPMDs and two different types of fortified sediment.

Tailoring Materials for Mottronics: Excess Oxygen Doping of a Prototypical Mott Insulator.

PubMed

Scheiderer, Philipp; Schmitt, Matthias; Gabel, Judith; Zapf, Michael; Stübinger, Martin; Schütz, Philipp; Dudy, Lenart; Schlueter, Christoph; Lee, Tien-Lin; Sing, Michael; Claessen, Ralph

2018-05-07

The Mott transistor is a paradigm for a new class of electronic devices-often referred to by the term Mottronics-which are based on charge correlations between the electrons. Since correlation-induced insulating phases of most oxide compounds are usually very robust, new methods have to be developed to push such materials right to the boundary to the metallic phase in order to enable the metal-insulator transition to be switched by electric gating. Here, it is demonstrated that thin films of the prototypical Mott insulator LaTiO 3 grown by pulsed laser deposition under oxygen atmosphere are readily tuned by excess oxygen doping across the line of the band-filling controlled Mott transition in the electronic phase diagram. The detected insulator to metal transition is characterized by a strong change in resistivity of several orders of magnitude. The use of suitable substrates and capping layers to inhibit oxygen diffusion facilitates full control of the oxygen content and renders the films stable against exposure to ambient conditions. These achievements represent a significant advancement in control and tuning of the electronic properties of LaTiO 3+ x thin films making it a promising channel material in future Mottronic devices. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Using Naturalistic Methods to Examine Real-World Driving Behavior in Individuals With TBI Upon Return to Driving: A Pilot Study.

PubMed

Hua, Phuong; Charlton, Judith L; Ponsford, Jennie L; Gooden, James R; Ross, Pamela E; Bédard, Michel; Marshall, Shawn; Gagnon, Sylvain; Stolwyk, Renerus J

2018-05-31

To characterize the real-world driving habits of individuals with traumatic brain injury (TBI) using naturalistic methods and to demonstrate the feasibility of such methods in exploring return to driving after TBI. After passing an on-road driving assessment, 8 participants with TBI and 23 matched controls had an in-vehicle device installed to record information regarding their driving patterns (distance, duration, and start/end times) for 90 days. The overall number of trips, distance and duration or percentage of trips during peak hour, above 15 km from home or on freeways/highways did not differ between groups. However, the TBI group drove significantly less at night, and more during the daytime, than controls. Exploratory analyses using geographic information system (GIS) also demonstrated significant within-group heterogeneity for the TBI group in terms of location of travel. The TBI and control groups were largely comparable in terms of driving exposure, except for when they drove, which may indicate small group differences in driving self-regulatory practices. However, the GIS evidence suggests driving patterns within the TBI group were heterogeneous. These findings provide evidence for the feasibility of employing noninvasive in-car recording devices to explore real-world driving behavior post-TBI.

Technologist radiation exposure in routine clinical practice with 18F-FDG PET.

PubMed

Guillet, Benjamin; Quentin, Pierre; Waultier, Serge; Bourrelly, Marc; Pisano, Pascale; Mundler, Olivier

2005-09-01

The use of 18F-FDG for clinical PET studies increases technologist radiation dose exposure because of the higher gamma-radiation energy of this isotope than of other conventional medical gamma-radiation-emitting isotopes. Therefore, 18F-FDG imaging necessitates stronger radiation protection requirements. The aims of this study were to assess technologist whole-body and extremity exposure in our PET department and to evaluate the efficiency of our radiation protection devices (homemade syringe drawing device, semiautomated injector, and video tracking of patients). Radiation dose assessment was performed for monodose as well as for multidose 18F-FDG packaging with both LiF thermoluminescence dosimeters (TLD) and electronic personal dosimeters (ED) during 5 successive 18F-FDG PET steps (from syringe filling to patient departure). The mean +/- SD total effective doses received by technologists (n = 50) during all of the working steps were 3.24 +/- 2.1 and 3.01 +/- 1.4 microSv, respectively, as measured with ED and TLD (345 +/- 84 MBq injected). These values were confirmed by daily TLD technologist whole-body dose measurements (2.98 +/- 1.8 microSv; 294 +/- 78 MBq injected; n = 48). Finger irradiation doses during preparation of single 18F-FDG syringes were 204.9 +/- 24 and 198.4 +/- 23 microSv with multidose vials (345 +/- 93 MBq injected) and 127.3 +/- 76 and 55.9 +/- 47 microSv with monodose vials (302 +/- 43 MBq injected) for the right hand and the left hand, respectively. The protection afforded by the semiautomated injector, estimated as the ratio of the doses received by TLD placed on the syringe shield and on the external face of the injector, was near 2,000. These results showed that technologist radiation doses in our PET department were lower than those reported in the literature. This finding may be explained by the use of a homemade syringe drawing device, a semiautomated injector, and patient video tracking, allowing a shorter duration of contact between the technologist and the patient. Extrapolation of these results to an annual dose (4 patients per day per technologist) revealed that the annual extrapolated exposure values remained under the authorized limits for workers classified to work in a radioactivity-controlled area.

Electromagnetic radiation and behavioural response of ticks: an experimental test.

PubMed

Vargová, Blažena; Majláth, Igor; Kurimský, Juraj; Cimbala, Roman; Kosterec, Michal; Tryjanowski, Piotr; Jankowiak, Łukasz; Raši, Tomáš; Majláthová, Viktória

2018-05-01

Factors associated with the increased usage of electronic devices, wireless technologies and mobile phones nowadays are present in increasing amounts in our environment. All living organisms are constantly affected by electromagnetic radiation which causes serious environmental pollution. The distribution and density of ticks in natural habitats is influenced by a complex of abiotic and biotic factors. Exposure to radio-frequency electromagnetic field (RF-EMF) constitutes a potential cause altering the presence and distribution of ticks in the environment. Our main objective was to determine the affinity of Dermacentor reticulatus ticks towards RF-EMF exposure. Originally designed and constructed radiation-shielded tube (RST) test was used to test the affinity of ticks under controlled laboratory conditions. All test were performed in an electromagnetic compatibility laboratory in an anechoic chamber. Ticks were irradiated using a Double-Ridged Waveguide Horn Antenna to RF-EMF at 900 and 5000 MHz, 0 MHz was used as control. The RF-EMF exposure to 900 MHz induced a higher concentration of ticks on irradiated arm of RST as opposed to the RF-EMF at 5000 MHz, which caused an escape of ticks to the shielded arm. This study represents the first experimental evidence of RF-EMF preference in D. reticulatus. The projection of obtained results to the natural environment could help assess the risk of tick borne diseases and could be a tool of preventive medicine.

The effectiveness of an air cleaner in controlling droplet/aerosol particle dispersion emitted from a patient's mouth in the indoor environment of dental clinics.

PubMed

Chen, Chun; Zhao, Bin; Cui, Weilin; Dong, Lei; An, Na; Ouyang, Xiangying

2010-07-06

Dental healthcare workers (DHCWs) are at high risk of occupational exposure to droplets and aerosol particles emitted from patients' mouths during treatment. We evaluated the effectiveness of an air cleaner in reducing droplet and aerosol contamination by positioning the device in four different locations in an actual dental clinic. We applied computational fluid dynamics (CFD) methods to solve the governing equations of airflow, energy and dispersion of different-sized airborne droplets/aerosol particles. In a dental clinic, we measured the supply air velocity and temperature of the ventilation system, the airflow rate and the particle removal efficiency of the air cleaner to determine the boundary conditions for the CFD simulations. Our results indicate that use of an air cleaner in a dental clinic may be an effective method for reducing DHCWs' exposure to airborne droplets and aerosol particles. Further, we found that the probability of droplet/aerosol particle removal and the direction of airflow from the cleaner are both important control measures for droplet and aerosol contamination in a dental clinic. Thus, the distance between the air cleaner and droplet/aerosol particle source as well as the relative location of the air cleaner to both the source and the DHCW are important considerations for reducing DHCWs' exposure to droplets/aerosol particles emitted from the patient's mouth during treatments.

The effectiveness of an air cleaner in controlling droplet/aerosol particle dispersion emitted from a patient's mouth in the indoor environment of dental clinics

PubMed Central

Chen, Chun; Zhao, Bin; Cui, Weilin; Dong, Lei; An, Na; Ouyang, Xiangying

2010-01-01

Dental healthcare workers (DHCWs) are at high risk of occupational exposure to droplets and aerosol particles emitted from patients' mouths during treatment. We evaluated the effectiveness of an air cleaner in reducing droplet and aerosol contamination by positioning the device in four different locations in an actual dental clinic. We applied computational fluid dynamics (CFD) methods to solve the governing equations of airflow, energy and dispersion of different-sized airborne droplets/aerosol particles. In a dental clinic, we measured the supply air velocity and temperature of the ventilation system, the airflow rate and the particle removal efficiency of the air cleaner to determine the boundary conditions for the CFD simulations. Our results indicate that use of an air cleaner in a dental clinic may be an effective method for reducing DHCWs' exposure to airborne droplets and aerosol particles. Further, we found that the probability of droplet/aerosol particle removal and the direction of airflow from the cleaner are both important control measures for droplet and aerosol contamination in a dental clinic. Thus, the distance between the air cleaner and droplet/aerosol particle source as well as the relative location of the air cleaner to both the source and the DHCW are important considerations for reducing DHCWs' exposure to droplets/aerosol particles emitted from the patient's mouth during treatments. PMID:20031985

Exposure to static magnetic fields and risk of accidents among a cohort of workers from a medical imaging device manufacturing facility.

PubMed

Bongers, Suzan; Slottje, Pauline; Portengen, Lützen; Kromhout, Hans

2016-05-01

To study the association between occupational MRI-related static magnetic fields (SMF) exposure and the occurrence of accidents. Recent and career SMF exposure was assessed by linking a retrospective job exposure matrix to payroll based job histories, for a cohort of (former) workers of an imaging device manufacturing facility in the Netherlands. Occurrence of accidents was collected through an online questionnaire. Self-reported injuries due to accidents in the past 12 months, and the first (near) traffic accident while commuting to work and from work were analyzed with logistic regression and discrete-time survival analyses, respectively. High recent SMF exposure was associated with an increased risk of accidents leading to injuries [odds ratio (OR) 4.16]. For high recent and career SMF exposure, an increased risk was observed for accidents resulting in physician-treated injuries (OR 5.78 and 2.79, respectively) and an increased lifetime risk of (near) accidents during commute to work (hazard ratios 2.49 and 2.45, respectively), but not from work. We found an association between MRI-related occupational SMF exposure and an increased risk of accidents leading to injury, and for commute-related (near) accidents during the commute from home to work. Further research into health effects of (long-term) SMF exposure is warranted to corroborate our findings. © 2015 Wiley Periodicals, Inc.

Adaptive Changes In Postural Equilibrium And Motion Sickness Following Repeated Exposures To Virtual Environments

NASA Technical Reports Server (NTRS)

Harm, D. L.; Taylor, L. C.

2006-01-01

Virtual environments offer unique training opportunities, particularly for training astronauts and preadapting them to the novel sensory conditions of microgravity. Two unresolved human factors issues in virtual reality (VR) systems are: 1) potential "cybersickness", and 2) maladaptive sensorimotor performance following exposure to VR systems. Interestingly, these aftereffects are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. Changes in the environmental sensory stimulus conditions and the way we interact with the new stimuli may result in motion sickness, and perceptual, spatial orientation and sensorimotor disturbances. Initial interpretation of novel sensory information may be inappropriate and result in perceptual errors. Active exploratory behavior in a new environment, with resulting feedback and the formation of new associations between sensory inputs and response outputs, promotes appropriate perception and motor control in the new environment. Thus, people adapt to consistent, sustained alterations of sensory input such as those produced by microgravity, unilateral labyrinthectomy and experimentally produced stimulus rearrangements. Adaptation is revealed by aftereffects including perceptual disturbances and sensorimotor control disturbances. The purpose of the current study was to compare disturbances in postural control produced by dome and head-mounted virtual environment displays, and to examine the effects of exposure duration, and repeated exposures to VR systems. Forty-one subjects (21 men, 20 women) participated in the study with an age range of 21-49 years old. One training session was completed in order to achieve stable performance on the posture and VR tasks before participating in the experimental sessions. Three experimental sessions were performed each separated by one day. The subjects performed a navigation and pick and place task in either a dome or head-mounted display (HMD) VR system for either 30 or 60 min. The environment was a square room with 15 pedestals on two opposite walls. The objects appeared on one set of pedestals and the subject s objective was to move the objects to the other set of pedestals. After the subject picked up an object, a pathway appeared and they were required to follow the pathway to the other side of the room. The subject was instructed to perform the task as quickly and accurately as possible, avoiding hitting walls and other any obstacles and placing the object on the center of the pedestal. Postural equilibrium was measured (using the Equitest CDP balance system, Neurocom, International) before, immediately after, and at 1 hr, 2 hr, 4 hr and 6 hr following exposure to VR. Postural equilibrium was measured during quiet stance with eyes open, eyes closed and vision and/or ankle proprioceptive inputs selectively altered by servo-controlling the visual surround and/or support surface to the subject s center of mass sway. Posture data was normalized using a log transformation and motion sickness data were normalized using the square root. In general, we found that exposure to VR resulted in decrements in postural stability. The largest decrements were observed in the tests performed immediately following exposure to VR and showed a fairly rapid recovery across the remaining test sessions. In addition, subjects generally showed improvement across days. We found significant main effects for day and time for the composite equilibrium score and for sensory organization tests (SOT) 1, 2 and 6. Significant main effects were observed for day for SOT 3 and 5. Although we found no significant main effects for gender (when center of gravity was used as a covariate), we did observe significant gender X time interaction effects for composite equilibrium and for SOT 1, 3, 4 and 5. Women appeared to show larger decrements in postural stability immediately after exposure to VR than men, but recover more quickly than n. Finally, we found no significant main effects for type of VR device or for exposure duration, however, these factors did interact with other factors during some of the SOTs. Subjects exhibited rapid recovery of motion sickness symptoms across time following exposure to VR and significantly less severe symptoms across days. We did not observe main effects for gender, type of device or duration of exposure. Individuals recovered from the detrimental effects of exposure to virtual reality on postural control and motion sickness within one hour. Sickness severity and initial decrements in postural equilibrium decreases over days, which suggests that subjects become dual-adapted over time. These findings provide some direction for developing training schedules for VR users that facilitate adaptation, and support the idea that preflight training of astronauts may serve as useful countermeasure for the sensorimotor effects of space flight.

Particle exposure and the historical loss of Native American ...

EPA Pesticide Factsheets

This is a letter to the editor-excerpt: An alternative reason for the devastating loss of Native American lives to infectious diseases introduced through interactions with Europeans could include an impact of exposure to particulate matter (PM) associated with the preparation of food and heating. In Europe, the chimney had developed by approximately 1600 as an architectural adaptation commonly employed in homes to diminish exposure of inhabitants to particles released during fuel combustion (3). Residences built in the Americas by Europeans had chimneys for the control of generated smoke. Use of either a chimney or an equivalent device to reduce indoor exposure to combustion products was uncommon in the domiciles of Native Americans (4). Often in these dwellings, fire pits were built in the ground in the center and there was either no exit or simply a hole in the peak (e.g. a smoke flap or smoke hole) for generated smoke to escape. Accordingly, Native American homes (e.g. tipis, wigwams, and long houses) were associated with exposures to high levels of smoke emitted from the burning of a biomass (e.g. wood). Extrapolating from comparable situations in which burning of biomass is used for preparation of food and heating, particle exposure would have been tens of thousands of micrograms per cubic meter in Native American domeciles and the lower respiratory tract of inhabitants was likely exposed from birth to a mass of PM equivalent to that of a cigarette s

Single-session gamified virtual reality exposure therapy for spider phobia vs. traditional exposure therapy: study protocol for a randomized controlled non-inferiority trial.

PubMed

Miloff, Alexander; Lindner, Philip; Hamilton, William; Reuterskiöld, Lena; Andersson, Gerhard; Carlbring, Per

2016-02-02

Traditional one-session exposure therapy (OST) in which a patient is gradually exposed to feared stimuli for up to 3 h in a one-session format has been found effective for the treatment of specific phobias. However, many individuals with specific phobia are reluctant to seek help, and access to care is lacking due to logistic challenges of accessing, collecting, storing, and/or maintaining stimuli. Virtual reality (VR) exposure therapy may improve upon existing techniques by facilitating access, decreasing cost, and increasing acceptability and effectiveness. The aim of this study is to compare traditional OST with in vivo spiders and a human therapist with a newly developed single-session gamified VR exposure therapy application with modern VR hardware, virtual spiders, and a virtual therapist. Participants with specific phobia to spiders (N = 100) will be recruited from the general public, screened, and randomized to either VR exposure therapy (n = 50) or traditional OST (n = 50). A behavioral approach test using in vivo spiders will serve as the primary outcome measure. Secondary outcome measures will include spider phobia questionnaires and self-reported anxiety, depression, and quality of life. Outcomes will be assessed using a non-inferiority design at baseline and at 1, 12, and 52 weeks after treatment. VR exposure therapy has previously been evaluated as a treatment for specific phobias, but there has been a lack of high-quality randomized controlled trials. A new generation of modern, consumer-ready VR devices is being released that are advancing existing technology and have the potential to improve clinical availability and treatment effectiveness. The VR medium is also particularly suitable for taking advantage of recent phobia treatment research emphasizing engagement and new learning, as opposed to physiological habituation. This study compares a market-ready, gamified VR spider phobia exposure application, delivered using consumer VR hardware, with the current gold standard treatment. Implications are discussed. ClinicalTrials.gov identifier NCT02533310. Registered on 25 August 2015.

Radio frequency electromagnetic radiation (RF-EMR) from GSM (0.9/1.8GHz) mobile phones induces oxidative stress and reduces sperm motility in rats.

PubMed

Mailankot, Maneesh; Kunnath, Anil P; Jayalekshmi, H; Koduru, Bhargav; Valsalan, Rohith

2009-01-01

Mobile phones have become indispensable in the daily lives of men and women around the globe. As cell phone use has become more widespread, concerns have mounted regarding the potentially harmful effects of RF-EMR from these devices. The present study was designed to evaluate the effects of RF-EMR from mobile phones on free radical metabolism and sperm quality. Male albino Wistar rats (10-12 weeks old) were exposed to RF-EMR from an active GSM (0.9/1.8 GHz) mobile phone for 1 hour continuously per day for 28 days. Controls were exposed to a mobile phone without a battery for the same period. The phone was kept in a cage with a wooden bottom in order to address concerns that the effects of exposure to the phone could be due to heat emitted by the phone rather than to RF-EMR alone. Animals were sacrificed 24 hours after the last exposure and tissues of interest were harvested. One hour of exposure to the phone did not significantly change facial temperature in either group of rats. No significant difference was observed in total sperm count between controls and RF-EMR exposed groups. However, rats exposed to RF-EMR exhibited a significantly reduced percentage of motile sperm. Moreover, RF-EMR exposure resulted in a significant increase in lipid peroxidation and low GSH content in the testis and epididymis. Given the results of the present study, we speculate that RF-EMR from mobile phones negatively affects semen quality and may impair male fertility.

Remotely operated submersible underwater suction apparatus

DOEpatents

Kristan, Louis L.

1990-01-01

A completely submersible, remotely operated underwater suction device for collection of irradiated materials in a nuclear pool is disclosed. The device includes a pump means for pumping water through the device, a filter means for capturing irradiated debris, remotely operated releasable connector means, a collection means and a means for remotely maneuvering the collection means. The components of the suction device may be changed and replaced underwater to take advantage of the excellent radiation shielding ability of water to thereby minimize exposure of personnel to radiation.

Controlling the Photophysical Properties of Semiconductor Quantum Dot Arrays by Strategically Altering Their Surface Chemistry

NASA Astrophysics Data System (ADS)

Marshall, Ashley R.

Semiconductor quantum dots (QDs) are interesting materials that, after less than 40 years of research, are used in commercial products. QDs are now found in displays, such as Samsung televisions and the Kindle Fire, and have applications in lighting, bio-imaging, quantum computing, and photovoltaics. They offer a large range of desirable properties: a controllable band gap, solution processability, controlled energy levels, and are currently the best materials for multiple exciton generation. The tunable optoelectronic properties of QDs can be controlled using size, shape, composition, and surface treatments--as shown here. Due to the quasi-spherical shape of QDs the surface to volume ratio is high, i.e. many of the constituent atoms are found on the QD surface. This makes QDs highly sensitive to surface chemistry modifications. This thesis encompasses the effects of surface treatments for QDs of two semiconducting materials: lead chalcogenides and CsPbI3. Our group developed a new synthetic technique for lead chalcogenide QDs via the cation exchange of cadmium chalcogenides. An in-depth chemical analysis is paired with optical and electrical studies and we find that metal halide residue contributes to the oxidative stability and decreased trap state density in cation-exchanged PbS QDs. We exploit these properties to make air-stable QD photovoltaic devices from both PbS and PbSe QD materials. Beyond the effects of residual atoms left from the synthetic technique, I investigated how to controllably add atoms onto the surface of QDs. I found that by introducing metal halides as a post-treatment in an electronically coupled array I am able to control the performance parameters in QD photovoltaic devices. These treatments fully infiltrate the assembled film, even under short exposure times and allow me to add controlled quantities of surface atoms to study their effects on film properties and photovoltaic device performance. Finally, I sought to apply the knowledge of the lead chalcogenide QD surfaces to produce QD photovoltaics from a new material: CsPbI3. I fabricated the first perovskite QD photovoltaic devices and using similar treatment methods as the lead chalcogenide QD arrays, I am able to influence the photophysical properties of CsPbI3 QD arrays.

Biological effects and physical safety aspects of NMR imaging and in vivo spectroscopy

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

Tenforde, T.S.; Budinger, T.F.

1985-08-01

An assessment is made of the biological effects and physical hazards of static and time-varying fields associated with the NMR devices that are being used for clinical imaging and in vivo spectroscopy. A summary is given of the current state of knowledge concerning the mechanisms of interaction and the bioeffects of these fields. Additional topics that are discussed include: (1) physical effects on pacemakers and metallic implants such as aneurysm clips, (2) human health studies related to the effects of exposure to nonionizing electromagnetic radiation, and (3) extant guidelines for limiting exposure of patients and medical personnel to the fieldsmore » produced by NMR devices. On the basis of information available at the present time, it is concluded that the fields associated with the current generation of NMR devices do not pose a significant health risk in themselves. However, rigorous guidelines must be followed to avoid the physical interaction of these fields with metallic implants and medical electronic devices. 476 refs., 5 figs., 2 tabs.« less

X-ray irradiation-induced structural changes on Single Wall Carbon Nanotubes

NASA Astrophysics Data System (ADS)

Bardi, N.; Jurewicz, I.; King, A. K.; Alkhorayef, M. A.; Bradley, D.; Dalton, A. B.

2017-11-01

Dosimetry devices based on Carbon Nanotubes are a promising new technology. In particular using devices based on single wall Carbon Nanotubes may offer a tissue equivalent response with the possibility for device miniaturisation, high scale manufacturing and low cost. An important precursor to device fabrication requires a quantitative study of the effects of X-ray radiation on the physical and chemical properties of the individual nanotubes. In this study, we concentrate on the effects of relatively low doses, 20 cGy and 45 cGy , respectively. We use a range of characterization techniques including scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy to quantify the effects of the radiation dose on inherent properties of the nanotubes. Specifically we find that the radiation exposure results in a reduction in the sp2 nature of the nanotube bond structure. Moreover, our analysis indicates that the exposure results in nanotubes that have an increased defect density which ultimately effects the electrical properties of the nanotubes.

Fabrication of 0.25-um electrode width SAW filters using x-ray lithography with a laser plasma source

NASA Astrophysics Data System (ADS)

Bobkowski, Romuald; Li, Yunlei; Fedosejevs, Robert; Broughton, James N.

1996-05-01

A process for the fabrication of surface acoustic wave (SAW) devices with line widths of 250 nm and less, based on x-ray lithography using a laser-plasma source has been developed. The x-ray lithography process is based on keV x-ray emission from Cu plasma produced by 15 Hz, 50 ps, 248 nm KrF excimer laser pulses. The full structure of a 2 GHz surface acoustic wave filter with interdigital transducers in a split-electrode geometry has been manufactured. The devices require patterning a 150 nm thick aluminum layer on a LiNbO3 substrate with electrodes 250 nm wide. The manufacturing process has two main steps: x-ray mask fabrication employing e-beam lithography and x-ray lithography to obtain the final device. The x-ray masks are fabricated on 1 micrometers thick membranes of Si2N4. The line patterns on the masks are written into PMMA resist using a scanning electron microscope which has been interfaced to a personal computer equipped to control the x and y scan voltages. The opaque regions of the x-ray mask are then formed by electroplating fine grain gold into the open spaces in the etched PMMA. The mask and sample are mounted in an exposure cassette with a fixed spacer of 10 micrometers separating them. The sample consists of a LiNbO3 substrate coated with Shipley XP90104C x-ray resist which has been previously characterized. The x-ray patterning is carried out in an exposure chamber with flowing helium background gas in order to minimize debris deposition on the filters. After etching the x-ray resist, the final patterns are produced using metallization and a standard lift-off technique. The SAW filters are then bonded and packaged onto impedance matching striplines. The resultant devices are tested using Scalar Network Analyzers. The final devices produced had a center frequency of 1.93 GHz with a bandwidth of 98 MHz, close to the expected performance of our simple design.

Image deblurring in smartphone devices using built-in inertial measurement sensors

NASA Astrophysics Data System (ADS)

Šindelář, Ondřej; Šroubek, Filip

2013-01-01

Long-exposure handheld photography is degraded with blur, which is difficult to remove without prior information about the camera motion. In this work, we utilize inertial sensors (accelerometers and gyroscopes) in modern smartphones to detect exact motion trajectory of the smartphone camera during exposure and remove blur from the resulting photography based on the recorded motion data. The whole system is implemented on the Android platform and embedded in the smartphone device, resulting in a close-to-real-time deblurring algorithm. The performance of the proposed system is demonstrated in real-life scenarios.

Risk Assessment of Neonatal Exposure to Low Frequency Noise Based on Balance in Mice

PubMed Central

Ohgami, Nobutaka; Oshino, Reina; Ninomiya, Hiromasa; Li, Xiang; Kato, Masashi; Yajima, Ichiro; Kato, Masashi

2017-01-01

General electric devices and ventilation systems are known to generate low frequency noise (LFN) with frequencies of <100 Hz. Previous studies showed that exposure to LFN caused impairments of balance in humans and mice during adulthood. On the other hand, a previous study showed that noise levels in the neonatal intensive care unit (NICU) were greater than those in general home or office environments. Therefore, it is possible that neonates have a potential risk to be exposed to LFN in the NICU. However, the risk of neonatal exposure to LFN remains unclear in humans and mice. In this study, male ICR mice were exposed to LFN at 100 Hz for 4 weeks after birth and then subjected to rotarod and beam crossing tests in order to assess LFN-mediated risk of imbalance during the neonatal period. Exposure to LFN at 70 dB, but not exposure to LFN up to 60 dB, during the neonatal period significantly decreased performance scores for rotarod and beam crossing tests compared to the scores of the control group. The number of calbindin-positive hair cells in the saccule and utricle was decreased in mice exposed to LFN at 70 dB for 4 weeks in the neonatal phase. Cessation of exposure for 10 weeks did not result in recovery of the decreased performance in rotarod and beam crossing tests. Thus, our results suggest that 70 dB is a possible threshold for exposure to LFN for 4 weeks during the neonatal period causing unrecoverable imbalance in mice. PMID:28275341

Postnatal hyperoxia or DEHP exposure leads to growth restriction and delayed lung development in newborn rats.

PubMed

Liang, Zhong-Jie; Wu, Qiu-Ping; Chen, Bei-Tao; Lin, Zhen-Lang; Lin, Jing; Chen, Shang-Qin

2018-02-01

Di-(2-ethylhexyl) phthalate (DEHP) is commonly used as a plasticizer in many medical devices. We previously showed that maternal DEHP exposure led to restricted growth and delayed lung maturation in newborn rats. As oxygen toxicity continues to be a major risk factor for bronchopulmonary dysplasia, the aim of this study was to examine the effect of hyperoxia, DEHP or DEHP combined with hyperoxia on the growth and lung maturation of newborn rats. Newborn rats received DEHP injection, hyperoxia exposure or DEHP injection combined with hyperoxia exposure for one week or two weeks. A control group received an equal volume of vehicle and was maintained in room air. Hyperoxia and hyperoxia + DEHP exposure for one week led to growth failure in newborn rats. Pups in the hyperoxia group showed catch-up growth after being maintained in room air for an additional 7 days but this was not the case with the latter group, which continued to receive DEHP. Hyperoxia and DEHP both delayed lung development, as evidenced by decreased radial alveolar count. Quantitative RT-PCR showed that hyperoxia decreased the transcripts of VEGF, VEGFR-2 and eNOS on days 7 and 14, and DEHP exposure alone also led to decreased expression of VEGF gene in 14-day-old rat pups. Postnatal hyperoxia and/or DEHP exposure lead to growth restriction and delayed lung alveolar development. The VEGF gene expression was altered and may be involved as one of the possible molecular mechanisms. Copyright © 2017. Published by Elsevier B.V.

SU-F-BRA-16: Development of a Radiation Monitoring Device Using a Low-Cost CCD Camera Following Radionuclide Therapy

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

Taneja, S; Fru, L Che; Desai, V

Purpose: It is now commonplace to handle treatments of hyperthyroidism using iodine-131 as an outpatient procedure due to lower costs and less stringent federal regulations. The Nuclear Regulatory Commission has currently updated release guidelines for these procedures, but there is still a large uncertainty in the dose to the public. Current guidelines to minimize dose to the public require patients to remain isolated after treatment. The purpose of this study was to use a low-cost common device, such as a cell phone, to estimate exposure emitted from a patient to the general public. Methods: Measurements were performed using an Applemore » iPhone 3GS and a Cs-137 irradiator. The charge-coupled device (CCD) camera on the phone was irradiated to exposure rates ranging from 0.1 mR/hr to 100 mR/hr and 30-sec videos were taken during irradiation with the camera lens covered by electrical tape. Interactions were detected as white pixels on a black background in each video. Both single threshold (ST) and colony counting (CC) methods were performed using MATLAB®. Calibration curves were determined by comparing the total pixel intensity output from each method to the known exposure rate. Results: The calibration curve showed a linear relationship above 5 mR/hr for both analysis techniques. The number of events counted per unit exposure rate within the linear region was 19.5 ± 0.7 events/mR and 8.9 ± 0.4 events/mR for the ST and CC methods respectively. Conclusion: Two algorithms were developed and show a linear relationship between photons detected by a CCD camera and low exposure rates, in the range of 5 mR/hr to 100-mR/hr. Future work aims to refine this model by investigating the dose-rate and energy dependencies of the camera response. This algorithm allows for quantitative monitoring of exposure from patients treated with iodine-131 using a simple device outside of the hospital.« less

Dual-frequency ultrasound focal therapy for MRI-guided transurethral treatment of the prostate: Study in gel phantom

NASA Astrophysics Data System (ADS)

N'Djin, W. Apoutou; Mougenot, Charles; Kobelevskiy, Ilya; Ramsay, Elizabeth; Bronskill, Michael; Chopra, Rajiv

2012-11-01

Ultrasound thermal therapy of localized prostate cancer offers a minimally-invasive non-ionizing alternative [1-3] to surgery and radiotherapy. MRI-controlled transurethral ultrasound prostate therapy [4-6] has previously been investigated in a pilot human feasibility study [7], by treating a small sub-volume of prostate tissue. In this study, the feasibility of transurethral dual-frequency ultrasound focal therapy has been investigated in gel phantom. A database of pelvic anatomical models of human prostate cancer patients have been created using MR clinical images. The largest prostate boundary (47 cm3) was used to fabricate an anatomical gel phantom which included various MR characteristics to mimic prostate tissues, 4 localized tumors and surrounding prostate tissues. A 9-element transurethral ultrasound applicator working in dual-frequency mode (f = 4.6/14.5 MHz) was evaluated to heat: (i) the entire prostate volume (Full prostate treatment strategy), (ii) a prostate region restricted to tumors (Focal therapy). Acoustic power of each element and rotation rate of the device were adjusted in realtime based on MR-thermometry feedback control (nine thermal slices updated every 6.2s). Experiments have been performed using dual-frequency ultrasound exposures (surface Pmax: 20W.cm-2). (i) For full prostate heating, 7 elements of the device were used to cover the entire prostate length. The heating process was completed within 35 min. Ultrasound exposures at the fundamental frequency allowed full heating of the largest prostate radii (>18 mm), while exposures at the 3rd harmonic ensured homogeneous treatment of the smallest radii. Undertreated and overtreated regions represented respectively 2% and 17% of the prostate volume. (ii) For focal therapy, the target region was optimized to maintain safe regions in the prostate and to cover all tumor-mimics. Only 5 ultrasound elements were used to treat successfully all tumor-mimics within 26 min. Undertreated and overtreated regions each represented 7% of the prostate volume. MRI-guided transurethral ultrasound procedure enables full treatment and focal therapy in human prostate geometry. Prostate volume heating was fast compared to standard HIFU prostate treatments. Dual-frequency ultrasound exposures allowed optimal heat deposition in all prostate regions. The focal therapy strategy is promising as regard to safety and could contribute to enhance the post-treatment autonomy of the patient.

KENNEDY SPACE CENTER, FLA. - On a tour of the KSC Beach Corrosion Test Site, Louis MacDowell (right), Testbed manager, explains to Center Director Jim Kennedy a project being undertaken for the U.S. Navy. At left are nonchrome primers for aircraft being studied. Behind Kennedy is Lead Scientist Dr. Luz Marina Calle. Behind MacDowell is Dr. Paul Hintze, who is working on a graduate project for the National Research Council. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

NASA Image and Video Library

2003-08-21

KENNEDY SPACE CENTER, FLA. - On a tour of the KSC Beach Corrosion Test Site, Louis MacDowell (right), Testbed manager, explains to Center Director Jim Kennedy a project being undertaken for the U.S. Navy. At left are nonchrome primers for aircraft being studied. Behind Kennedy is Lead Scientist Dr. Luz Marina Calle. Behind MacDowell is Dr. Paul Hintze, who is working on a graduate project for the National Research Council. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

KENNEDY SPACE CENTER, FLA. - On a tour of the KSC Beach Corrosion Test Site, Center Director Jim Kennedy (second from right) learns from Testbed Manager Louis MacDowell (right) about a project being undertaken for the U.S. Navy. Being studied are nonchrome primers for aircraft. At left are Lead Scientist Dr. Luz Marina Calle and Dr. Paul Hintze, who is working on a graduate project for the National Research Council. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

NASA Image and Video Library

2003-08-21

KENNEDY SPACE CENTER, FLA. - On a tour of the KSC Beach Corrosion Test Site, Center Director Jim Kennedy (second from right) learns from Testbed Manager Louis MacDowell (right) about a project being undertaken for the U.S. Navy. Being studied are nonchrome primers for aircraft. At left are Lead Scientist Dr. Luz Marina Calle and Dr. Paul Hintze, who is working on a graduate project for the National Research Council. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

KENNEDY SPACE CENTER, FLA. - On a tour of the KSC Beach Corrosion Test Site, Testbed Manager Louis MacDowell (foreground) explains to Center Director Jim Kennedy (third from right) about a study being undertaken for the U.S. Navy: nonchrome primers for aircraft. At left is Lead Scientist Dr. Luz Marina Calle and behind MacDowell is Dr. Paul Hintze, who is working on a graduate project for the National Research Council. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

NASA Image and Video Library

2003-08-21

KENNEDY SPACE CENTER, FLA. - On a tour of the KSC Beach Corrosion Test Site, Testbed Manager Louis MacDowell (foreground) explains to Center Director Jim Kennedy (third from right) about a study being undertaken for the U.S. Navy: nonchrome primers for aircraft. At left is Lead Scientist Dr. Luz Marina Calle and behind MacDowell is Dr. Paul Hintze, who is working on a graduate project for the National Research Council. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

The influence of jet engine noise on hearing of technical staff.

PubMed

Konopka, Wiesław; Pawlaczyk-Luszczyńska, Małgorzata; Śliwińska-Kowalska, Mariola

2014-01-01

Due to high sound pressure levels (SPLs), noise produced by jet planes may be harmful to hearing of people working in their proximity. The aim of this study was to assess the effects of exposure to jet engine noise on technical staff hearing. The study comprised 60 men, aged 24-50 years, employed in army as technical staff and exposed to jet engine noise for 6-20 years. The control group were 50 non-noise exposed males, aged 25-51 years. Exposure to noise emitted by jet engines was evaluated. Pure-tone audiometry (PTA) and distortion product otoacoustic emissions (DPOAE) were recorded in both groups. Jet engines emitted broadband noise with spectrum dominated by components in the frequency range 315-6300 Hz (1/3-octave bands). Maximum A-weighted SPL during tests reached values of approx. 120-130 dB. Consequently, engine-servicing personnel (even in the case of a single engine test) was exposed to noise (at A-weighted daily noise exposure level above 95 dB) exceeding permissible levels. Averaged audiometric hearing threshold levels of technical staff were higher (≤ 17 dB HL, p < 0.001) than in the control group. Similarly, the DPOAE amplitude was lower (≤ 17 dB SPL, p < 0.01) in the noise-exposed subjects compared to the non-exposed ones. Significant reduction of DPOAE levels was mainly noted for high frequencies (3-6 kHz). Despite the usage of hearing protection devices, both PTA and DPOAE consistently showed poorer hearing in engine-servicing personnel vs. control group.

Surveillance and Outbreak Response Management System (SORMAS) to support the control of the Ebola virus disease outbreak in West Africa.

PubMed

Fähnrich, C; Denecke, K; Adeoye, O O; Benzler, J; Claus, H; Kirchner, G; Mall, S; Richter, R; Schapranow, M P; Schwarz, N; Tom-Aba, D; Uflacker, M; Poggensee, G; Krause, G

2015-03-26

In the context of controlling the current outbreak of Ebola virus disease (EVD), the World Health Organization claimed that 'critical determinant of epidemic size appears to be the speed of implementation of rigorous control measures', i.e. immediate follow-up of contact persons during 21 days after exposure, isolation and treatment of cases, decontamination, and safe burials. We developed the Surveillance and Outbreak Response Management System (SORMAS) to improve efficiency and timeliness of these measures. We used the Design Thinking methodology to systematically analyse experiences from field workers and the Ebola Emergency Operations Centre (EOC) after successful control of the EVD outbreak in Nigeria. We developed a process model with seven personas representing the procedures of EVD outbreak control. The SORMAS system architecture combines latest In-Memory Database (IMDB) technology via SAP HANA (in-memory, relational database management system), enabling interactive data analyses, and established SAP cloud tools, such as SAP Afaria (a mobile device management software). The user interface consists of specific front-ends for smartphones and tablet devices, which are independent from physical configurations. SORMAS allows real-time, bidirectional information exchange between field workers and the EOC, ensures supervision of contact follow-up, automated status reports, and GPS tracking. SORMAS may become a platform for outbreak management and improved routine surveillance of any infectious disease. Furthermore, the SORMAS process model may serve as framework for EVD outbreak modeling.

Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

DTIC Science & Technology

2013-10-01

Engineering Research Laboratory has made a momentous advancement on meeting the proposed milestones. The project has two objectives, in which the ...pressure plasma jet based on a dielectric barrier discharge configuration. The plasma and biological testing and characterization are in progress...1(b). Direct exposure of plasma involves, exposure of plasma directly on to a target treatment surface whereas the indirect plasma exposure involves

Observations of Interference between Portable Particle Counters and NOx Monitors

EPA Science Inventory

Studies in environmental exposure science have developed a preference for smaller devices that can be easily co-located without need for gas standards, such as those instruments utilized in the Near-road Exposures and Effects from Urban Air Pollutants Study (NEXUS). One operatio...

Exposure to non-ionizing electromagnetic radiation from mobile telephony and the association with psychiatric symptoms.

PubMed

Silva, Denize Francisca da; Barros, Warley Rocha; Almeida, Maria da Conceição Chagas de; Rêgo, Marco Antônio Vasconcelos

2015-10-01

The aim of this study was to investigate the association between exposure to non-ionizing electromagnetic radiation from mobile phone base stations and psychiatric symptoms. In a cross-sectional study in Salvador, Bahia State, Brazil, 440 individuals were interviewed. Psychiatric complaints and diagnoses were the dependent variables and distance from the individual's residence to the base station was considered the main independent variable. Hierarchical logistic regression analysis was conducted to assess confounding. An association was observed between psychiatric symptoms and residential proximity to the base station and different forms of mobile phone use (making calls with weak signal coverage, keeping the mobile phone close to the body, having two or more chips, and never turning off the phone while sleeping), and with the use of other electronic devices. The study concluded that exposure to electromagnetic radiation from mobile phone base stations and other electronic devices was associated with psychiatric symptoms, independently of gender, schooling, and smoking status. The adoption of precautionary measures to reduce such exposure is recommended.

Validation of an electronic device for measuring driving exposure.

PubMed

Huebner, Kyla D; Porter, Michelle M; Marshall, Shawn C

2006-03-01

This study sought to evaluate an on-board diagnostic system (CarChip) for collecting driving exposure data in older drivers. Drivers (N = 20) aged 60 to 86 years from Winnipeg and surrounding communities participated. Information on driving exposure was obtained via the CarChip and global positioning system (GPS) technology on a driving course, and obtained via the CarChip and surveys over a week of driving. Velocities and distances were measured over the road course to validate the accuracy of the CarChip compared to GPS for those parameters. The results show that the CarChip does provide valid distance measurements and slightly lower maximum velocities than GPS measures. From the results obtained in this study, it was determined that retrospective self-reports of weekly driving distances are inaccurate. Therefore, an on-board diagnostic system (OBDII) electronic device like the CarChip can provide valid and detailed information about driving exposure that would be useful for studies of crash rates or driving behavior.

40 CFR 60.2141 - By what date must I conduct the initial air pollution control device inspection?

Code of Federal Regulations, 2011 CFR

2011-07-01

... air pollution control device inspection? 60.2141 Section 60.2141 Protection of Environment... initial air pollution control device inspection? (a) The initial air pollution control device inspection... startup. (b) Within 10 operating days following an air pollution control device inspection, all necessary...

40 CFR 60.2141 - By what date must I conduct the initial air pollution control device inspection?

Code of Federal Regulations, 2012 CFR

2012-07-01

... air pollution control device inspection? 60.2141 Section 60.2141 Protection of Environment... initial air pollution control device inspection? (a) The initial air pollution control device inspection... startup. (b) Within 10 operating days following an air pollution control device inspection, all necessary...

Analgesic effect of simultaneous exposure to infrared laser radiation and μT magnetic field in rats

NASA Astrophysics Data System (ADS)

Cieslar, Grzegorz; Mrowiec, Janina; Kasperczyk, Slawomir; Sieron-Stoltny, Karolina; Sieron, Aleksander

2008-03-01

The aim of the experiment was to estimate the effect of repeated simultaneous exposures to infrared laser radiation and μT variable magnetic field used in magnetostimulation on pain perception in rats, as well as the involvement of endogenous opioid system in the mechanism of this effect. In experimental group clean-shaven scull of male Wistar rats placed individually in a specially designed plastic chamber were simultaneously exposed to infrared laser radiation (wavelength - 855 nm, mean power - 4,1 mW, energy density - 30 J/cm2) and variable magnetic field of saw-like shape of impulse, at a frequency of basic impulse 180-195 Hz and mean induction value of 120 μT generated by magneto-laser applicator of device for magnetostimulation Viofor JPS (Med & Life, Poland) 12 minutes daily for 2 periods of 5 consecutive days, with 2 days-lasting break between them, while control animals were sham-exposed. The pain perception was determined by means of "hot plate" test on the basis of calculated analgesic index. As a result of repeated exposures a significant increase in analgesic index persisting also till 14 th day after the end of a cycle of exposures was observed. This analgesic effect was inhibited by prior i.p. injection of opioid antagonist - Naloxone.

14 CFR 23.373 - Speed control devices.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Speed control devices. 23.373 Section 23....373 Speed control devices. If speed control devices (such as spoilers and drag flaps) are incorporated....441 and 23.443, with the device extended at speeds up to the placard device extended speed; and (b) If...

14 CFR 23.373 - Speed control devices.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Speed control devices. 23.373 Section 23....373 Speed control devices. If speed control devices (such as spoilers and drag flaps) are incorporated....441 and 23.443, with the device extended at speeds up to the placard device extended speed; and (b) If...

NEW APPLICATION OF PASSIVE SAMPLING DEVICES FOR ASSESSMENT OF RESPIRATORY EXPOSURE TO PESTICIDES IN INDOOR AIR

EPA Science Inventory

The United States Environmental Protection Agency (EPA) has long maintained an interest in potential applications of passive sampling devices (PSDs) for estimating the concentrations of various pollutants in air. Typically PSDs were designed for the workplace monitoring of vola...

The Dose Response Relationship between In Ear Occupational Noise Exposure and Hearing Loss

PubMed Central

Rabinowitz, Peter M.; Galusha, Deron; Dixon-Ernst, Christine; Clougherty, Jane E.; Neitzel, Richard L.

2014-01-01

Objectives Current understanding of the dose-response relationship between occupational noise and hearing loss is based on cross-sectional studies prior to the widespread use hearing protection and with limited data regarding noise exposures below 85dBA. We report on the hearing loss experience of a unique cohort of industrial workers with daily monitoring of noise inside of hearing protection devices. Methods At an industrial facility, workers exhibiting accelerated hearing loss were enrolled in a mandatory program to monitor daily noise exposures inside of hearing protection. We compared these noise measurements (as time-weighted LAVG) to interval rates of high frequency hearing loss over a six year period using a mixed effects model, adjusting for potential confounders. Results Workers’ high frequency hearing levels at study inception averaged more than 40 dB hearing threshold level (HTL). Most noise exposures were less than 85dBA (mean LAVG 76 dBA, interquartile range 74 to 80 dBA). We found no statistical relationship between LAvg and high frequency hearing loss (p = 0.53). Using a metric for monthly maximum noise exposure did not improve model fit. Conclusion At-ear noise exposures below 85dBA did not show an association with risk of high frequency hearing loss among workers with substantial past noise exposure and hearing loss at baseline. Therefore, effective noise control to below 85dBA may lead to significant reduction in occupational hearing loss risk in such individuals. Further research is needed on the dose response relationship of noise and hearing loss in individuals with normal hearing and little prior noise exposure. PMID:23825197

Ambient and microenvironmental particles and exhaled nitric oxide before and after a group bus trip.

PubMed

Adar, Sara Dubowsky; Adamkiewicz, Gary; Gold, Diane R; Schwartz, Joel; Coull, Brent A; Suh, Helen

2007-04-01

Airborne particles have been linked to pulmonary oxidative stress and inflammation. Because these effects may be particularly great for traffic-related particles, we examined associations between particle exposures and exhaled nitric oxide (FE(NO)) in a study of 44 senior citizens, which involved repeated trips aboard a diesel bus. Samples of FE(NO) collected before and after the trips were regressed against microenvironmental and ambient particle concentrations using mixed models controlling for subject, day, trip, vitamins, collection device, mold, pollen, room air nitric oxide, apparent temperature, and time to analysis. Although ambient concentrations were collected at a fixed location, continuous group-level personal samples characterized microenvironmental exposures throughout facility and trip periods. In pre-trip samples, both microenvironmental and ambient exposures to fine particles were positively associated with FE(NO). For example, an interquartile increase of 4 microg/m(3) in the daily microenvironmental PM(2.5) concentration was associated with a 13% [95% confidence interval (CI), 2-24%) increase in FE(NO). After the trips, however, FE(NO) concentrations were associated pre-dominantly with microenvironmental exposures, with significant associations for concentrations measured throughout the whole day. Associations with exposures during the trip also were strong and statistically significant with a 24% (95% CI, 15-34%) increase in FE(NO) predicted per interquartile increase of 9 microg/m(3) in PM(2.5). Although pre-trip findings were generally robust, our post-trip findings were sensitive to several influential days. Fine particle exposures resulted in increased levels of FE(NO) in elderly adults, suggestive of increased airway inflammation. These associations were best assessed by microenvironmental exposure measurements during periods of high personal particle exposures.

Ambient and Microenvironmental Particles and Exhaled Nitric Oxide Before and After a Group Bus Trip

PubMed Central

Adar, Sara Dubowsky; Adamkiewicz, Gary; Gold, Diane R.; Schwartz, Joel; Coull, Brent A.; Suh, Helen

2007-01-01

Objectives Airborne particles have been linked to pulmonary oxidative stress and inflammation. Because these effects may be particularly great for traffic-related particles, we examined associations between particle exposures and exhaled nitric oxide (FENO) in a study of 44 senior citizens, which involved repeated trips aboard a diesel bus. Methods Samples of FENO collected before and after the trips were regressed against microenvironmental and ambient particle concentrations using mixed models controlling for subject, day, trip, vitamins, collection device, mold, pollen, room air nitric oxide, apparent temperature, and time to analysis. Although ambient concentrations were collected at a fixed location, continuous group-level personal samples characterized microenvironmental exposures throughout facility and trip periods. Results In pre-trip samples, both microenvironmental and ambient exposures to fine particles were positively associated with FENO. For example, an interquartile increase of 4 μg/m3 in the daily microenvironmental PM2.5 concentration was associated with a 13% [95% confidence interval (CI), 2–24%) increase in FENO. After the trips, however, FENO concentrations were associated pre-dominantly with microenvironmental exposures, with significant associations for concentrations measured throughout the whole day. Associations with exposures during the trip also were strong and statistically significant with a 24% (95% CI, 15–34%) increase in FENO predicted per interquartile increase of 9 μg/m3 in PM2.5. Although pre-trip findings were generally robust, our post-trip findings were sensitive to several influential days. Conclusions Fine particle exposures resulted in increased levels of FENO in elderly adults, suggestive of increased airway inflammation. These associations were best assessed by microenvironmental exposure measurements during periods of high personal particle exposures. PMID:17450216

Simple methods to reduce patient exposure during scoliosis radiography

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

Butler, P.F.; Thomas, A.W.; Thompson, W.E.

1986-05-01

Radiation exposure to the breasts of adolescent females can be reduced significantly through the use of one or all of the following methods: fast, rare-earth screen-film combinations; specially designed compensating filters; and breast shielding. The importance of exposure reduction during scoliosis radiography as well as further details on the above described methods are discussed. In addition, the early results of a Center for Devices and Radiological Health study, which recorded exposure and technique data for scoliosis radiography, is presented.

Evaluating the accuracy, reliability, and clinical applicability of continuous glucose monitoring (CGM): Is CGM ready for real time?

PubMed

Mazze, Roger S; Strock, Ellie; Borgman, Sarah; Wesley, David; Stout, Philip; Racchini, Joel

2009-01-01

This study was designed to assess the accuracy, reliability, and contribution to clinical decision-making of two commercially available continuous glucose monitoring (CGM) devices using a novel analytical approach. Eleven individuals with type 1 diabetes and five with type 2 diabetes wore a Guardian RT (GRT) (Medtronic Minimed, Northridge, CA) or DexCom STS Continuous Monitoring System (DEX) (San Diego, CA) device for 200 h followed by an 8-h laboratory study. A subset of these subjects wore both devices simultaneously. Subjects produced 1,902 +/- 269 readings during the ambulatory phase. During the laboratory study we found: lag time of 21 +/- 5 min for GRT and 7 +/- 7 min for DEX (P < 0.005); mean absolute relative difference of 19.9% and 16.7%, respectively, for GRT and DEX; and glucose exposure (the ratio of study device/laboratory reference device [YSI Instruments, Inc., Yellow Springs, OH] area under the curve) of 95 +/- 6% for GRT and 101 +/- 13% for DEX. Reliability measured during laboratory study showed 82% for DEX and 99% for GRT. Clarke Error Grid analysis (YSI reference) showed for GRT 59% of values in zone A, 34% in zone B, and 7% in zone D and for DEX 70% in zone A, 28% in zone B, 1% in zone C, and 1% in zone D. Bland-Altman plots (YSI standard) yielded for DEX 3 mg/dL (95% confidence interval, -78 to 84 mg/dL) and for GRT -21 mg/dL (95% confidence interval, -124 to 82 mg/dL). Six of eight subjects completed both home and laboratory simultaneous use of DEX and GRT. Lag times were inconsistent between devices, ranging from 0 to 32 min; area under the curve revealed a tendency for DEX to report higher total glucose exposure than GRT for the same patient. CGM detects abnormalities in glycemic control in a manner heretofore impossible to obtain. However, our studies revealed sufficient incongruence between simultaneous laboratory blood glucose levels and interstitial fluid glucose (after calibrations) to question the fundamental assumption that interstitial fluid glucose and blood glucose could be made identical by resorting to algorithms based on concurrent blood glucose levels alone.

Tulip deformity with Cera atrial septal defect devices: a report of 3 cases.

PubMed

Kohli, Vikas

2015-02-01

Device closure of secundum atrial septal defect (ASD) is the treatment of choice when anatomy is favourable. Amplatzer device has remained the gold standard for closure of ASD. Cobra deformity is a well-reported problem with devices. Recently, Tulip deformity has been reported in a single case. We report a series of cases where we noted Tulip deformity along with inability to retract the device in the sheath in Cera Lifetech devices. This resulted in prolongation of procedure, excessive fluoroscopic exposure and additional interventional procedures not usually anticipated in ASD device closure. We believe that the problem is due to the stiffness of the device resulting in its inability to be retracted into the sheath. We also report a unique way of retrieving the device.

Stent deployment protocol for optimized real-time visualization during endovascular neurosurgery.

PubMed

Silva, Michael A; See, Alfred P; Dasenbrock, Hormuzdiyar H; Ashour, Ramsey; Khandelwal, Priyank; Patel, Nirav J; Frerichs, Kai U; Aziz-Sultan, Mohammad A

2017-05-01

Successful application of endovascular neurosurgery depends on high-quality imaging to define the pathology and the devices as they are being deployed. This is especially challenging in the treatment of complex cases, particularly in proximity to the skull base or in patients who have undergone prior endovascular treatment. The authors sought to optimize real-time image guidance using a simple algorithm that can be applied to any existing fluoroscopy system. Exposure management (exposure level, pulse management) and image post-processing parameters (edge enhancement) were modified from traditional fluoroscopy to improve visualization of device position and material density during deployment. Examples include the deployment of coils in small aneurysms, coils in giant aneurysms, the Pipeline embolization device (PED), the Woven EndoBridge (WEB) device, and carotid artery stents. The authors report on the development of the protocol and their experience using representative cases. The stent deployment protocol is an image capture and post-processing algorithm that can be applied to existing fluoroscopy systems to improve real-time visualization of device deployment without hardware modifications. Improved image guidance facilitates aneurysm coil packing and proper positioning and deployment of carotid artery stents, flow diverters, and the WEB device, especially in the context of complex anatomy and an obscured field of view.

Canine toys and training devices as sources of exposure to phthalates and bisphenol A: quantitation of chemicals in leachate and in vitro screening for endocrine activity.

PubMed

Wooten, Kimberly J; Smith, Philip N

2013-11-01

Chewing and mouthing behaviors exhibited by pet dogs are likely to lead to oral exposures to a variety of environmental chemicals. Products intended for chewing and mouthing uses include toys and training devices that are often made of plastics. The goal of the current study was to determine if a subset of phthalates and bisphenol A (BPA), endocrine disrupting chemicals commonly found in plastics, leach out of dog toys and training devices (bumpers) into synthetic canine saliva. In vitro assays were used to screen leachates for endocrine activity. Bumper leachates were dominated by di-2-ethylhexyl phthalate (DEHP) and BPA, with concentrations reaching low μg mL(-1) following short immersions in synthetic saliva. Simulated chewing of bumpers during immersion in synthetic saliva increased concentrations of phthalates and BPA as compared to new bumpers, while outdoor storage had variable effects on concentrations (increased DEHP; decreased BPA). Toys leached substantially lower concentrations of phthalates and BPA, with the exception of one toy which leached considerable amounts of diethyl phthalate. In vitro assays indicated anti-androgenic activity of bumper leachates, and estrogenic activity of both bumper and toy leachates. These results confirm that toys and training devices are potential sources of exposure to endocrine disrupting chemicals in pet dogs. Copyright © 2013 Elsevier Ltd. All rights reserved.

Risk assessment of electromagnetic fields exposure with metallic orthopedic implants: a cadaveric study.

PubMed

Crouzier, D; Selek, L; Martz, B-A; Dabouis, V; Arnaud, R; Debouzy, J-C

2012-02-01

Metallic materials are well known to strongly interact with electromagnetic fields. While biological effects of such field have been extensively studied, only few works dealt with the interactions of electromagnetic waves with passive metallic device implanted in biological system. Hence only several numerical and phantom simulation studies were focusing on this aspect, whereas no in situ anatomic experiment has been previously performed. In this study the effect of electromagnetic waves on eight different orthopaedic medical devices (six plates from 55 to 318mm length, a total knee and a total hip prosthesis) were explored on six human cadavers. To mimic a random environmental exposure resulting from the most common frequencies band used in domestic environment and medical applications (TV and radio broadcasting, cell phone communication, MRI, diathermy treatment), a multifrequency generator emitting in VHF, UHF, GSM and GCS frequency bands was used. The different medical devices were exposed to an electromagnetic field at 50W/m(2) and 100W/m(2). After 6min exposure, the temperature was measured on three points close to each medical device, and the induced currents were estimated. No significant temperature increase (<0.2°C) was finally detected; beside, a slight induced tension (up to 1.1V) was recorded but would appear too low to induce any biological side effect. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

77 FR 28460 - National Standards for Traffic Control Devices; the Manual on Uniform Traffic Control Devices for...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-14

...-2010-0159] RIN 2125-AF43 National Standards for Traffic Control Devices; the Manual on Uniform Traffic Control Devices for Streets and Highways; Revision AGENCY: Federal Highway Administration (FHWA..., approved by the FHWA, and recognized as the national standard for traffic control devices used on all...

Impact of the Volkswagen emissions control defeat device on US public health

NASA Astrophysics Data System (ADS)

Barrett, Steven R. H.; Speth, Raymond L.; Eastham, Sebastian D.; Dedoussi, Irene C.; Ashok, Akshay; Malina, Robert; Keith, David W.

2015-11-01

The US Environmental Protection Agency (EPA) has alleged that Volkswagen Group of America (VW) violated the Clean Air Act (CAA) by developing and installing emissions control system ‘defeat devices’ (software) in model year 2009-2015 vehicles with 2.0 litre diesel engines. VW has admitted the inclusion of defeat devices. On-road emissions testing suggests that in-use NOx emissions for these vehicles are a factor of 10 to 40 above the EPA standard. In this paper we quantify the human health impacts and associated costs of the excess emissions. We propagate uncertainties throughout the analysis. A distribution function for excess emissions is estimated based on available in-use NOx emissions measurements. We then use vehicle sales data and the STEP vehicle fleet model to estimate vehicle distance traveled per year for the fleet. The excess NOx emissions are allocated on a 50 km grid using an EPA estimate of the light duty diesel vehicle NOx emissions distribution. We apply a GEOS-Chem adjoint-based rapid air pollution exposure model to produce estimates of particulate matter and ozone exposure due to the spatially resolved excess NOx emissions. A set of concentration-response functions is applied to estimate mortality and morbidity outcomes. Integrated over the sales period (2008-2015) we estimate that the excess emissions will cause 59 (95% CI: 10 to 150) early deaths in the US. When monetizing premature mortality using EPA-recommended data, we find a social cost of ˜450m over the sales period. For the current fleet, we estimate that a return to compliance for all affected vehicles by the end of 2016 will avert ˜130 early deaths and avoid ˜840m in social costs compared to a counterfactual case without recall.

Development of a new passive sampler based on diffusive milligel beads for copper analysis in water.

PubMed

Perez, M; Reynaud, S; Lespes, G; Potin-Gautier, M; Mignard, E; Chéry, P; Schaumlöffel, D; Grassl, B

2015-08-26

A new passive sampler was designed and characterized for the determination of free copper ion (Cu(2+)) concentration in aqueous solution. Each sampling device was composed of a set of about 30 diffusive milligel (DMG) beads. Milligel beads with incorporated cation exchange resin (Chelex) particles were synthetized using an adapted droplet-based millifluidic process. Beads were assumed to be prolate spheroids, with a diameter of 1.6 mm and an anisotropic factor of 1.4. The milligel was controlled in chemical composition of hydrogel (monomer, cross-linker, initiator and Chelex concentration) and characterized in pore size. Two types of sampling devices were developed containing 7.5% and 15% of Chelex, respectively, and 6 nm pore size. The kinetic curves obtained demonstrated the accumulation of copper in the DMG according to the process described in the literature as absorption (and/or adsorption) and release following the Fick's first law of diffusion. For their use in water monitoring, the typical physico-chemical characteristics of the samplers, i.e. the mass-transfer coefficient (k0) and the sampler-water partition coefficient (Ksw), were determined based on a static exposure design. In order to determine the copper concentration in the samplers after their exposure, a method using DMG bead digestion combined to Inductively Coupled Plasma - Atomic Emission Spectrometry (ICP-AES) analysis was developed and optimized. The DMG devices proved to be capable to absorb free copper ions from an aqueous solution, which could be accurately quantified with a mean recovery of 99% and a repeatability of 7% (mean relative uncertainty). Copyright © 2015 Elsevier B.V. All rights reserved.

Comprehensive study of the influence of different environments on degradation processes in F8BT: Correlating optoelectronic properties with Raman measurements

NASA Astrophysics Data System (ADS)

Linde, Sivan; Shikler, Rafi

2013-10-01

There is a growing interest in conjugated polymers from both industrial and academic points of views. The reasons are their tunable optoelectronic properties, ease of production, and excellent mechanical properties. However, the ease with which their optoelectronic properties are tunable make devices based on them prone to fast degradation and therefore, short life time. The issue of degradation of organic based optoelectronic devices is the topic of many ongoing researches. However, much less attention is given to degradation processes of the individual components of the devices and their dependence on the environmental conditions. In this work, we report on the degradation of a film of a polyfluorene block copolymer F8BT that is used in a variety of optoelectronic devices under different environments: Sun exposure, heating, and UV exposure in inert and ambient conditions. Degradation was observed in most of the optoelectronic properties of the film. Topographic measurements did not show observable changes of the film morphology following degradation. However, Raman spectroscopy measurements show changes that indicate degradation in one of the building blocks of the copolymer that is associated with electron's conduction. The absolute value of the correlation coefficient between the decrease in the Raman signal and the decrease in the optoelectronic properties is larger than 0.95 under sun exposure it is larger than 0.8 under all other ambient exposures and smaller than 0.65 under inert conditions. These results support the assumption that Oxygen, not necessarily through photo-oxidation, and also water play an important role in the degradation process and indicate the part of the polymer that is most susceptible to degradation.

Effects of electromagnetic field exposure on the heart: a systematic review.

PubMed

Elmas, Onur

2016-01-01

The use of electrical devices has gradually increased throughout the last century, and scientists have suggested that electromagnetic fields (EMF) generated by such devices may have harmful effects on living creatures. This work represents a systematic review of collective scholarly literature examining the effects of EMFs on the heart. Although most works describing effects of EMF exposure have been carried out using city electric frequencies (50-60 Hz), a consensus has not been reached about whether long- or short-term exposure to 50-60 Hz EMF negatively affects the heart. Studies have indicated that EMFs produced at cell-phone frequencies cause no-effect on the heart. Differences between results of studies may be due to a compensatory response developed by the body over time. At greater EMF strengths or shorter exposures, the ability of the body to develop compensation mechanisms is reduced and the potential for heart-related effects increases. It is noteworthy that diseases of heart tissues such as myocardial ischemia can also be successfully treated using EMF. Despite the substantial volume of data that has been collected on heart-related effects of EMFs, additional studies are needed at the cellular and molecular level to fully clarify the subject. Until the effects of EMF on heart tissue are more fully explored, electronic devices generating EMFs should be approached with caution. © The Author(s) 2013.

Guidance to employers on integrating e-cigarettes/electronic nicotine delivery systems into tobacco worksite policy.

PubMed

Whitsel, Laurie P; Benowitz, Neal; Bhatnagar, Aruni; Bullen, Chris; Goldstein, Fred; Matthias-Gray, Lena; Grossmeier, Jessica; Harris, John; Isaac, Fikry; Loeppke, Ron; Manley, Marc; Moseley, Karen; Niemiec, Ted; OʼBrien, Vince; Palma-Davis, LaVaughn; Pronk, Nico; Pshock, Jim; Stave, Gregg M; Terry, Paul

2015-03-01

In recent years, new products have entered the marketplace that complicate decisions about tobacco control policies and prevention in the workplace. These products, called electronic cigarettes (e-cigarettes) or electronic nicotine delivery systems, most often deliver nicotine as an aerosol for inhalation, without combustion of tobacco. This new mode of nicotine delivery raises several questions about the safety of the product for the user, the effects of secondhand exposure, how the public use of these products should be handled within tobacco-free and smoke-free air policies, and how their use affects tobacco cessation programs, wellness incentives, and other initiatives to prevent and control tobacco use. In this article, we provide a background on e-cigarettes and then outline key policy recommendations for employers on how the use of these new devices should be managed within worksite tobacco prevention programs and control policies.

Effects of gravity on the circadian period in rats

NASA Technical Reports Server (NTRS)

Murakami, Dean M.; Demaria, Victor H.; Fuller, Charles A.

1991-01-01

The effect of increased gravity force on the circadian period of body temperature and activity of rats was investigated using rats implanted with a small radio telemetry device and, after a 2-week recovery and a 3-week control period at 1G, rotated at for 4 weeks at a constant 2G field in a 18-ft-diam centrifuge. Measurements of the mean freerunning period of the temperature and activity rhythms after 10 days showed that the exposure to 2G led to a functional separation of the pacemakers that regulate the activity and the temperature in the animals. Each pacemaker reacted differently: the activity period increased and the temperature period decreased. By the third or the fourth week, the activity and the temperature periods have returned to 1G control levels.

Frequency spectra from current vs. magnetic flux density measurements for mobile phones and other electrical appliances.

PubMed

Straume, Aksel; Johnsson, Anders; Oftedal, Gunnhild; Wilén, Jonna

2007-10-01

The frequency spectra of electromagnetic fields have to be determined to evaluate human exposure in accordance to ICNIRP guidelines. In the literature, comparisons with magnetic field guidelines have been performed by using the frequency distribution of the current drawn from the battery. In the present study we compared the frequency spectrum in the range 217 Hz to 2.4 kHz of the magnetic flux density measured near the surface of a mobile phone with the frequency spectrum of the supply current. By using the multiple frequency rule, recommended in the ICNIRP guidelines, we estimated the magnetic field exposure in the two cases. Similar measurements and estimations were done for an electric drill, a hair dryer, and a fluorescent desk lamp. All the devices have a basic frequency of 50 Hz, and the frequency spectra were evaluated up to 550 Hz. We also mapped the magnetic field in 3D around three mobile phones. The frequency distributions obtained from the two measurement methods are not equal. The frequency content of the current leads to an overestimation of the magnetic field exposure by a factor up to 2.2 for the mobile phone. For the drill, the hair dryer, and the fluorescent lamp, the supply current signal underestimated the exposure by a factor up to 2.3. In conclusion, an accurate exposure evaluation requires the magnetic flux density spectrum of the device to be measured directly. There was no indication that the devices studied would exceed the reference levels at the working distances normally used.

A comparison of 15 Hz sine on-line and off-line magnetic stimulation affecting the voltage-gated sodium channel currents of prefrontal cortex pyramidal neurons

NASA Astrophysics Data System (ADS)

Zheng, Yu; Dong, Lei; Gao, Yang; Dou, Jun-Rong; Li, Ze-yan

2016-10-01

Combined with the use of patch-clamp techniques, repetitive transcranial magnetic stimulation (rTMS) has proven to be a noninvasive neuromodulation tool that can inhibit or facilitate excitability of neurons after extensive research. The studies generally focused on the method: the neurons are first stimulated in an external standard magnetic exposure device, and then moved to the patch-clamp to record electrophysiological characteristics (off-line magnetic exposure). Despite its universality, real-time observation of the effects of magnetic stimulation on the neurons is more effective (on-line magnetic stimulation). In this study, we selected a standard exposure device for magnetic fields acting on mouse prefrontal cortex pyramidal neurons, and described a new method that a patch-clamp setup was modified to allow on-line magnetic stimulation. By comparing the off-line exposure and on-line stimulation of the same magnetic field intensity and frequency affecting the voltage-gated sodium channel currents, we succeeded in proving the feasibility of the new on-line stimulation device. We also demonstrated that the sodium channel currents of prefrontal cortex pyramidal neurons increased significantly under the 15 Hz sine 1 mT, and 2 mT off-line magnetic field exposure and under the 1 mT and 2 mT on-line magnetic stimulation, and the rate of acceleration was most significant on 2 mT on-line magnetic stimulation. This study described the development of a new on-line magnetic stimulator and successfully demonstrated its practicability for scientific stimulation of neurons.

Occupational noise exposure during endourologic procedures.

PubMed

Soucy, Frédéric; Ko, Raymond; Denstedt, John D; Razvi, Hassan

2008-08-01

Long-term noise exposure in the workplace is a known cause of hearing loss. There has been limited study on the potential harm related to shock wave lithotripsy (SWL) or intracorporeal devices on patients and operating room personnel. We used a digital sound meter to measure decibel levels in the operating room during several endourologic procedures. The decibel levels were recorded during SWL (Storz SLX-F2), percutaneous nephrolithotomy using single- and dual-probe ultrasonic lithotripters (Olympus LUS-2, CyberWand), and during ureteroscopy using the Versa Pulse Holmium:YAG laser. Findings were compared with the U.S. Department of Labor Occupational Health and Safety Administration and Canadian Centre for Occupational Health recommendations on permissible noise levels in the workplace. The background sound level in the operating room prior to endourologic procedures ranged between 58 and 60 dB. In the SWL control room, 5 m from the source, the mean sound level was 68 dB (range 64-75) during treatment. The mean corresponding decibel level recorded at the patient's head during SWL was 77 dB (range 73-83). Noises produced by intracorporeal lithotripters were recorded at the surgeon's head, 2 m from the source. Measurements of the CyberWand (dual-probe) device revealed a higher mean decibel reading of 93 dB (range 85-102). Noise levels recorded for the Olympus LUS-2 (single-probe) ultrasound and the holmium laser were 65 dB (62 -68) and 60 dB (58-62), respectively. Although we noted that patients and urologists maybe exposed to significant noise levels during endourologic procedures, the duration of exposure is short. This risk appears to be minimal, based on current occupational guidelines, for most operating personnel.

Protective effects of β-glucan against oxidative injury induced by 2.45-GHz electromagnetic radiation in the skin tissue of rats.

PubMed

Ceyhan, Ali Murat; Akkaya, Vahide Baysal; Güleçol, Şeyma Celik; Ceyhan, Betül Mermi; Özgüner, Fehmi; Chen, WenChieh

2012-09-01

In recent times, there is widespread use of 2.45-GHz irradiation-emitting devices in industrial, medical, military and domestic application. The aim of the present study was to investigate the effect of 2.45-GHz electromagnetic radiation (EMR) on the oxidant and antioxidant status of skin and to examine the possible protective effects of β-glucans against the oxidative injury. Thirty-two male Wistar albino rats were randomly divided into four equal groups: control; sham exposed; EMR; and EMR + β-glucan. A 2.45-GHz EMR emitted device from the experimental exposure was applied to the EMR group and EMR + β-glucan group for 60 min daily, respectively, for 4 weeks. β-glucan was administered via gavage at a dose of 50 mg/kg/day before each exposure to radiation in the treatment group. The activities of antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), as well as the concentration of malondialdehyde (MDA) were measured in tissue homogenates of the skin. Exposure to 2.45-GHz EMR caused a significant increase in MDA levels and CAT activity, while the activities of SOD and GSH-Px decreased in skin tissues. Systemic β-glucan significantly reversed the elevation of MDA levels and the reduction of SOD activities. β-glucan treatment also slightly enhanced the activity of CAT and prevented the depletion of GSH-Px activity caused by EMR, but not statistically significantly. The present study demonstrated the role of oxidative mechanisms in EMR-induced skin tissue damages and that β-glucan could ameliorate oxidative skin injury via its antioxidant properties.

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

Code of Federal Regulations, 2010 CFR

2010-10-01

... transmission of a signal. In general, maximum average power levels must be used to determine compliance. (3) If... workers that can be easily re-located, such as wireless devices associated with a personal computer, are... Satellite Communications Services, the General Wireless Communications Service, the Wireless Communications...

10 CFR 34.85 - Records of radiation surveys.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Records of radiation surveys. 34.85 Section 34.85 Energy... INDUSTRIAL RADIOGRAPHIC OPERATIONS Recordkeeping Requirements § 34.85 Records of radiation surveys. Each licensee shall maintain a record of each exposure device survey conducted before the device is placed in...

10 CFR 34.85 - Records of radiation surveys.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Records of radiation surveys. 34.85 Section 34.85 Energy... INDUSTRIAL RADIOGRAPHIC OPERATIONS Recordkeeping Requirements § 34.85 Records of radiation surveys. Each licensee shall maintain a record of each exposure device survey conducted before the device is placed in...

10 CFR 34.85 - Records of radiation surveys.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Records of radiation surveys. 34.85 Section 34.85 Energy... INDUSTRIAL RADIOGRAPHIC OPERATIONS Recordkeeping Requirements § 34.85 Records of radiation surveys. Each licensee shall maintain a record of each exposure device survey conducted before the device is placed in...

10 CFR 34.85 - Records of radiation surveys.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Records of radiation surveys. 34.85 Section 34.85 Energy... INDUSTRIAL RADIOGRAPHIC OPERATIONS Recordkeeping Requirements § 34.85 Records of radiation surveys. Each licensee shall maintain a record of each exposure device survey conducted before the device is placed in...

10 CFR 34.31 - Inspection and maintenance of radiographic exposure devices, transport and storage containers...

Code of Federal Regulations, 2013 CFR

2013-01-01

... devices, transport and storage containers, associated equipment, source changers, and survey instruments... changers, and survey instruments. (a) The licensee shall perform visual and operability checks on survey... condition, that the sources are adequately shielded, and that required labeling is present. Survey...