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Sample records for extremely-low frequency elf

  1. Study of extremely low frequency electromagnetic field (ELF EMF) radiation produced by consumer products

    International Nuclear Information System (INIS)

    Roha Tukimin; Ahmad Fazli Ahmad Sanusi; Rozaimah Abd Rahim; Mohd Yusof Mohd Ali; Mohamad Amirul Nizam Mohamad Thari

    2006-01-01

    Extremely low frequency electromagnetic field ( ELF EMF) radiation falls under category of non-ionising radiation (NIR).ELF EMF consists of electric and magnetic fields. Excessive exposure to ELF EMF radiation may cause biological and health effects to human beings such as behavioral changes, stochastic and as initiator of cancer. In daily life, the main source of extremely low frequency electromagnetic radiation are consumer products in our home and office. Due to its ability to cause hazard, a study of ELF EMF radiation produced by consumer product was conducted. For this preliminary study, sample of 20 types electrical appliances were selected. The measurement was covered electric and magnetic field strength produced by the sample. PMM model EHP50A were used for measurement and data analysis. The results were compared with the permissible limits recommended by International Commission of Non-Ionising Radiation Protection (ICNIRP) for members of public (1000 mGauss and 5000 V/m). The results showed that all tested sample produced magnetic and electric field but still under the permissible limit recommended by ICNIRP. Besides that we found that field strengths can be very high at closer distance to the sample. (Author)

  2. Extremely Low Frequency Electromagnetic Field (ELF-EMF and childhood leukemia near transmission lines: a review

    Directory of Open Access Journals (Sweden)

    P. A. Kokate

    2016-04-01

    Full Text Available This article presents a systematic review of most cited studies from developed countries those shed light on the potential relation between childhood leukemia and extremely low frequency electromagnetic field (ELF-EMF. All the findings of articles critically segregated as per some neglected parameters like number of samples, exposure duration, frequency range, distance from the radiation sources, and location during measurement of magnetic field density near power lines. Literature of major 50 studies are divided according to pooled analysis / meta-analysis, residential zone assessment and case-control studies.

  3. Exposure of Extremely-Low Frequency (ELF magnetic field may cause human cancer

    Directory of Open Access Journals (Sweden)

    Daryoush Shahbazi-Gahrouei

    2017-01-01

    Full Text Available Introduction: Chronic exposure of non-ionizing extremely low-frequency magnetic fields (ELF-EMF is considered as a health hazard due to its adverse effects on human body such as generation of any type of cancer. Stem cells are appropriate models to assess the effects of ELF-EMF on other cell lines and human beings. Materials and methods: Adipose tissue has been known as source of multi potent stromal human mesenchymal stem cells (MSCs which can be obtained in less invasive method and in large amounts; so adipose-derived stem cells (ADSCs were used in this study. Effect of ELF-EMF (intensities of 0.5 and 1 mT and 50 Hz on proliferation rate of hADSCs was assessed in 20 and 40 min per day for 7 days. Trypan blue assay was performed to assess cell proliferation rate. Result: The results shown that 0.5 and 1 mT magnetic fields can promote the proliferation rate of adipose derived hMSCs according to the duration of exposure. Conclusion: These outcomes could approve the effect of ELF-EMF on cancer induction; although the effective mechanisms in this process are still unknown.

  4. Investigation of exposure to Extremely Low Frequency (ELF) magnetic and electric fields: Ongoing animal studies

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, L.E.

    1994-03-01

    There is now convincing evidence from a large number of laboratories, that exposure to extremely low frequency (ELF) magnetic and electric fields produces biological responses in animals. Many of the observed effects appear to be directly or indirectly associated with the neural or neuroendocrine systems. Such effects include increased neuronal excitability, chemical and hormonal changes in the nervous system, altered behavioral responses, some of which are related to sensing the presence of the field, and changes in endogenous biological rhythms. Additional indices of general physiological status appear relatively unaffected by exposure, although effects have occasionally been described in bone growth and fracture repair, reproduction and development, and immune system function. A major current emphasis in laboratory research is to determine whether or not the reported epidemiological studies that suggest an association between EMF exposure and risk of cancer are supported in studies using animal models. Three major challenges exist for ongoing research: (1) knowledge about the mechanisms underlying observed bioeffects is incomplete, (2) researchers do not as yet understand what physical aspects of exposure produce biological responses, and (3) health consequences resulting from ELF exposure are unknown. Although no animal studies clearly demonstrate deleterious effects of ELF fields, several are suggestive of potential health impacts. From the perspective of laboratory animal studies, this paper will discuss biological responses to ELF magnetic and/or electric field exposures.

  5. Inhibition of Salmonella typhi growth using extremely low frequency electromagnetic (ELF-EM) waves at resonance frequency.

    Science.gov (United States)

    Fadel, M A; Mohamed, S A; Abdelbacki, A M; El-Sharkawy, A H

    2014-08-01

    Typhoid is a serious disease difficult to be treated with conventional drugs. The aim of this study was to demonstrate a new method for the control of Salmonella typhi growth, through the interference with the bioelectric signals generated from the microbe during cell division by extremely low frequency electromagnetic waves (ELF-EMW-ELF-EM) at resonance frequency. Isolated Salmonella typhi was subjected to square amplitude modulated waves (QAMW) with different modulation frequencies from two generators with constant carrier frequency of 10 MHz, amplitude of 10 Vpp, modulating depth ± 2 Vpp and constant field strength of 200 V m(-1) at 37°C. Both the control and exposed samples were incubated at the same conditions during the experiment. The results showed that there was highly significant inhibition effect for Salm. typhi exposed to 0·8 Hz QAMW for a single exposure for 75 min. Dielectric relaxation, TEM and DNA results indicated highly significant changes in the molecular structure of the DNA and cellular membrane resulting from the exposure to the inhibiting EM waves. It was concluded that finding out the inhibiting resonance frequency of ELF-EM waves that deteriorates Salm. typhi growth will be promising method for the treatment of Salm. typhi infection either in vivo or in vitro. This new non-invasive technique for treatment of bacterial infections is of considerable interest for the use in medical and biotechnological applications. © 2014 The Society for Applied Microbiology.

  6. Extremely Low Frequency-Magnetic Fields (ELF-EMF) occupational exposure and natural killer activity in peripheral blood lymphocytes

    International Nuclear Information System (INIS)

    Gobba, Fabriziomaria; Bargellini, Annalisa; Scaringi, Meri; Bravo, Giulia; Borella, Paola

    2009-01-01

    Extremely Low Frequency-Magnetic Fields (ELF-MF) are possible carcinogens to humans and some data suggest that they can act as promoters or progressors. Since NK cells play a major role in the control of cancer development, an adverse effect on ELF-MF on NK function has been hypothesized. We examined NK activity in 52 workers exposed to different levels of ELF-MF in various activities. Individual exposure was monitored during 3 complete work-shifts using personal dosimeters. Environmental exposure was also monitored. ELF-MF levels in the workers were expressed as Time-Weighted Average (TWA) values. NK activity was measured in peripheral blood lymphocytes (PBL). In the whole group the median occupational TWA was 0.21 μT. According to the TWA levels, workers were classified as low exposed (26 subjects, TWA ≤ 0.2 μT) and higher exposed workers (26 subjects; TWA > 0.2 μT). In higher exposed workers, we observed a trend to reduce NK activity compared to low exposed, but the difference was not significant. Then we selected a subgroup of highest exposed workers (12 subjects; TWA > 1 μT); no difference was observed between low and highest exposed subjects in the main personal variables. Considering both E:T ratios from 12:1 to 50:1 and Lytic Units, a significant reduction in NK activity was observed in the highest exposed workers compared to the low exposed. Multivariate analysis showed a significant negative correlation between exposure and LU, while no correlation was evidenced with other personal characteristics. ELF-MF are considered possible carcinogens, and existing data suggest that they can act as promoters. Due to the role of NK activity in host defence against cancer, the results obtained in this study in workers exposed to ELF-MF levels exceeding 1 μT are in agreement with this hypothesis, and support the need for further investigation in this field

  7. Extremely Low Frequency (ELF) Communications System Ecological Monitoring Program: Plan and Summary of 1982 Progress.

    Science.gov (United States)

    1983-08-01

    Scientific studies were funded through a peer-reviewed, competitive bidding process in mid-1982, and studies were initiated at the Wisconsin and Michigan ELF...Naval Electronic Systems Command (NESC) during and subsequent to the ELF Comunications Program environmental impact evaluation process, includ- ing the... scientific review of ELF electromagnetic field effects made by the National Academy of Sciences in 1977. This document generally describes the

  8. Residential exposure from extremely low frequency electromagnetic field (ELF EMF) radiation

    Science.gov (United States)

    Parthasarathy, Shamesh Raj; Tukimin, Roha

    2018-01-01

    ELF EMF radiation have received considerable attention as a potential threat to the safety and health of people living in the vicinity of high voltage transmission lines, electric distribution substations, power stations and even in close proximity to electronics and electrical household appliances. The paper highlights the study on the ELF EMF safety assessment performed at residences comprising of an owner-occupied house, a completed vacant house and an under construction condominium. The objectives of this study were to determine the ELF EMF radiation exposure level from the high voltage transmission line, electric distribution substation, power station and electrical household appliances in the residences, and to assess the potential exposure received by the occupants at the assessed locations. The results were logged in the electric and magnetic field strength with the units of volt per meter (V/m) and miliGauss (mG) respectively. The instrument setup and measurement protocols during the assessment were adopted from standard measurement method and procedures stipulated under the Institute of Electrical and Electronics Engineers (IEEE) Standard. The results were compared with the standards recommended in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines.

  9. Extremely low frequency electromagnetic field (ELF-EMF) reduces oxidative stress and improves functional and psychological status in ischemic stroke patients.

    Science.gov (United States)

    Cichoń, Natalia; Bijak, Michał; Miller, Elżbieta; Saluk, Joanna

    2017-07-01

    As a result of ischaemia/reperfusion, massive generation of reactive oxygen species occurs, followed by decreased activity of antioxidant enzymes. Extremely low frequency electromagnetic fields (ELF-EMF) can modulate oxidative stress, but there are no clinical antioxidant studies in brain stroke patients. The aim of our study was to investigate the effect of ELF-EMF on clinical and antioxidant status in post-stroke patients. Fifty-seven patients were divided into two groups: ELF-EMF and non-ELF-EMF. Both groups underwent the same 4-week rehabilitation program. Additionally, the ELF-EMF group was exposed to an ELF-EMF field of 40 Hz, 7 mT for 15 min/day for 4 weeks (5 days a week). The activity of catalase and superoxide dismutase was measured in hemolysates, and total antioxidant status (TAS) determined in plasma. Functional status was assessed before and after the series of treatments using Activities of Daily Living (ADL), Mini-Mental State Examination (MMSE), and Geriatric Depression Scale (GDS). Applied ELF-EMF significantly increased enzymatic antioxidant activity; however, TAS levels did not change in either group. Results show that ELF-EMF induced a significant improvement in functional (ADL) and mental (MMSE, GDS) status. Clinical parameters had positive correlation with the level of enzymatic antioxidant protection. Bioelectromagnetics. 38:386-396, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  10. Study on the Extremely Low Frequency (ELF) Electromagnetic Field (EMF) emission from overhead High-Voltage Transmission Lines

    International Nuclear Information System (INIS)

    Parthasarathy, S.R.; Roha Tukimin; Wan Saffiey Wan Abdullah; Zulkifli Yusof; Mohd Azizi Mohd Jali

    2016-01-01

    The paper highlights the study on the Extremely Low Frequency (ELF) Electromagnetic Field (EMF) emission performed at an overhead 275-kV High-Voltage Transmission Lines. The study comprised of assessment at the transmission lines on 3 different cases and locations in Klang Valley, specifically on a vacant land near the transmission line, inside and around the house at the vicinity of the transmission line and the area directly under the transmission line. The instrument setup and measurement protocols during the assessment were adopted from standard measurement method and procedures stipulated under the Institute of Electrical and Electronics Engineers (IEEE) Standard. The results were compared with the standards recommended in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. The results showed that the measured field strengths are within the safety limit with the highest measured exposure was 10.8 % and 1.8 % of the permissible exposure limit for the electric and magnetic field respectively. Both the field strengths were found to drop significantly against distance from the transmission lines where closer distances showed higher field strengths. Furthermore, the study revealed that buildings and other object such as trees and shrubs screen out the electric field, resulting in a lower value at indoor measurements and near the stated objects. In addition, higher value of electric and magnetic field strengths were recorded when assessment was being done directly under the transmission line compared to the lateral measurement. (author)

  11. Assessment of every day extremely low frequency (Elf) electromagnetic fields (50-60 Hz) exposure: which metrics?

    International Nuclear Information System (INIS)

    Verrier, A.; Magne, I.; Souqes, M.; Lambrozo, J.

    2006-01-01

    Because electricity is encountered at every moment of the day, at home with household appliances, or in every type of transportation, people are most of the time exposed to extremely low frequency (E.L.F.) electromagnetic fields (50-60 Hz) in a various way. Due to a lack of knowledge about the biological mechanisms of 50 Hz magnetic fields, studies seeking to identify health effects of exposure use central tendency metrics. The objective of our study is to provide better information about these exposure measurements from three categories of metrics. We calculated metrics of exposure measurements from data series (79 very day exposed subjects), made up approximately 20,000 recordings of magnetic fields, measured every 30 seconds for 7 days with an E.M.D.E.X. II dosimeter. These indicators were divided into three categories : central tendency metrics, dispersion metrics and variability metrics.We use Principal Component Analysis, a multidimensional technique to examine the relations between different exposure metrics for a group of subjects. Principal component Analysis (P.C.A.) enabled us to identify from the foreground 71.7% of the variance. The first component (42.7%) was characterized by central tendency; the second (29.0%) was composed of dispersion characteristics. The third component (17.2%) was composed of variability characteristics. This study confirm the need to improve exposure measurements by using at least two dimensions intensity and dispersion. (authors)

  12. Preliminary study : Extremely low frequency electromagnetic field (ELF EMF) effects on the growth of plant

    International Nuclear Information System (INIS)

    Roha Tukimin; Wan Norsuhaila Wan Aziz; Rozaimah Abd Rahim; Wan Saffiey Wan Abdulah

    2010-01-01

    A research has been done to study the effects of magnetic fields on the growth of plants.Two samples of maize seedlings and green beans have been studied. Helmholtz coil systems were used as magnetic field source at frequency 50 Hz with 440 mGauss field strength. Sample characteristics such height, leaf, colour and length of roots were observed. The results show that the magnetic field influenced the growth of the sample. The sample that were exposed to the magnetic field show faster growth compared to the controlled sample. (author)

  13. Effects of extremely low frequency electromagnetic field (ELF-EMF) on catalase, cytochrome P450 and nitric oxide synthase in erythro-leukemic cells.

    Science.gov (United States)

    Patruno, Antonia; Tabrez, Shams; Pesce, Mirko; Shakil, Shazi; Kamal, Mohammad A; Reale, Marcella

    2015-01-15

    Extremely low frequency electromagnetic fields (ELF-EMFs) are widely employed in electrical appliances and different equipment such as television sets, mobile phones, computers and microwaves. The molecular mechanism through which ELF-EMFs can influence cellular behavior is still unclear. A hypothesis is that ELF-EMFs could interfere with chemical reactions involving free radical production. Under physiologic conditions, cells maintain redox balance through production of ROS/RNS and antioxidant molecules. The altered balance between ROS generation and elimination plays a critical role in a variety of pathologic conditions including neurodegenerative diseases, aging and cancer. Actually, there is a disagreement as to whether there is a causal or coincidental relationship between ELF-EMF exposure and leukemia development. Increased ROS levels have been observed in several hematopoietic malignancies including acute and chronic myeloid leukemias. In our study, the effect of ELF-EMF exposure on catalase, cytochrome P450 and inducible nitric oxide synthase activity and their expression by Western blot analysis in myelogenous leukemia cell line K562 was evaluated. A significant modulation of iNOS, CAT and Cyt P450 protein expression was recorded as a result of ELF-EMF exposure in both phorbol 12-myristate 13-acetate (PMA)-stimulated and non-stimulated cell lines. Modulation in kinetic parameters of CAT, CYP-450 and iNOS enzymes in response to ELF-EMF indicates an interaction between the ELF-EMF and the enzymological system. These new insights might be important in establishing a mechanistic framework at the molecular level within which the possible effects of ELF-EMF on health can be understood. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Effects of whole body exposure to extremely low frequency electromagnetic fields (ELF-EMF on serum and liver lipid levels, in the rat

    Directory of Open Access Journals (Sweden)

    Elias-Viñas David

    2007-11-01

    Full Text Available Abstract Backgound The effects of extremely low-frequency electromagnetic fields (ELF-EMF on the blood serum and liver lipid concentrations of male Wistar rats were assessed. Methods Animals were exposed to a single stimulation (2 h of ELF-EMF (60 Hz, 2.4 mT or sham-stimulated and thereafter sacrificed at different times (24, 48 or 96 h after beginning the exposure. Results Blood lipids showed, at 48 h stimulated animals, a significant increase of cholesterol associated to high density lipoproteins (HDL-C than those observed at any other studied time. Free fatty acid serum presented at 24 h significant increases in comparison with control group. The other serum lipids, triacylglycerols and total cholesterol did not show differences between groups, at any time evaluated. No statistical differences were shown on total lipids of the liver but total cholesterol was elevated at 24 h with a significant decrease at 96 h (p = 0.026. The ELF-EMF stimulation increased the liver content of lipoperoxides at 24 h. Conclusion Single exposures to ELF-EMF increases the serum values of HDL-C, the liver content of lipoperoxides and decreases total cholesterol of the liver. The mechanisms for the effects of ELF-EMF on lipid metabolism are not well understand yet, but could be associated to the nitric oxide synthase EMF-stimulation.

  15. Evaluation of the effects of Extremely Low Frequency (ELF Pulsed Electromagnetic Fields (PEMF on survival of the bacterium Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Ahmed Istiaque

    2013-12-01

    In summary, the growth rate of the irradiated S. aureus bacteria is affected by radiation of particular parameters, thus revealing resonant effects induced by the applied radiation. The decreased CFU values in all irradiated samples compared to control samples (non-exposed were observed. Findings provide important insight towards selecting the optimal parameters of ELF PEMF for possible treatment of infected tissue and thus, wound healing promotion.

  16. Assessment of Extremely Low Frequency (ELF Electric and Magnetic Fields in Hamedan High Electrical Power Stations and their Effects on Workers

    Directory of Open Access Journals (Sweden)

    Farshid Ghorbani Shahna

    2011-09-01

    Full Text Available Introduction: Public and occupational exposure to extremely low frequency (ELF electric and magnetic fields induced by electrical equipment is a significant issue in the environment and at the workplace due to their potential health effects on public health. The purpose of this study was assessment of the electric and magnetic fields intensities and determination of mental and psychological effects of occupational exposure in the high voltage electric power stations in the city of Hamadan, Iran. Material and Methods: The intensities of the magnetic and electric fields were measured at eight high voltage electric power stations at three different intervals of sources using an HI-3604 instrument. A two-part questionnaire was used to assess mental and psychological effects of the exposure to these fields. Two groups of control and case workers including 30 samples were selected to determine the exposure effects. Results: The results of field measurements showed the highest average electric field intensity was related to the CVT unit with 3110 V/m at a 2 m distance from the source and the lowest average was related to the control room with 1.35 V/m next to the source. Also, the highest and lowest magnetic field intensities were close to the transformator 2 and the battery room (50.42 and 1.31 mG, respectively. Discussion and Conclusion: The intensities of electric and magnetic fields in the selected stations are lower than the ACGIH and ICNIRP standard levels for occupational exposures. The results obtained indicate that the distribution of these fields was nonlinear around the sources and the effects observed on exposed workers were non-thermal.

  17. Extreme Low Frequency Acoustic Measurement System

    Science.gov (United States)

    Shams, Qamar A. (Inventor); Zuckerwar, Allan J. (Inventor)

    2017-01-01

    The present invention is an extremely low frequency (ELF) microphone and acoustic measurement system capable of infrasound detection in a portable and easily deployable form factor. In one embodiment of the invention, an extremely low frequency electret microphone comprises a membrane, a backplate, and a backchamber. The backchamber is sealed to allow substantially no air exchange between the backchamber and outside the microphone. Compliance of the membrane may be less than ambient air compliance. The backplate may define a plurality of holes and a slot may be defined between an outer diameter of the backplate and an inner wall of the microphone. The locations and sizes of the holes, the size of the slot, and the volume of the backchamber may be selected such that membrane motion is substantially critically damped.

  18. Interaction of extremely-low-frequency electromagnetic fields with humans

    International Nuclear Information System (INIS)

    Tenforde, T.S.

    1991-07-01

    At a macroscopic level, the effects of extremely low frequency (ELF) electromagnetic fields on humans are well understood based on fundamental physical principles, but far less is known about the nature of the interactions at a cellular or molecular level. Current evidence suggests the effects of ELF on cellular biochemistry are due to interactions with the cell membrane. Elucidation of the mechanism that underlies this transmembrane signaling is critical for a molecular-level understanding of ELF field effects. Further research is also required to clarify a possible link between ELF exposure and increased cancer risk, since estimated ELF exposure in occupational or residential settings is much lower that the levels used in laboratory studies. There is a clear need for additional epidemiological research in which qualitative dosimetry is used to characterize ELF exposure and careful attention is given to possible effects of confounding variables. 24 refs

  19. Assessment of extremely low frequency magnetic field exposure from GSM mobile phones

    NARCIS (Netherlands)

    Calderón, Carolina; Addison, Darren; Mee, Terry; Findlay, Richard; Maslanyj, Myron; Conil, Emmanuelle; Kromhout, Hans; Lee, Ae Kyoung; Sim, Malcolm R.; Taki, Masao; Varsier, Nadège; Wiart, Joe; Cardis, Elisabeth

    2014-01-01

    Although radio frequency (RF) electromagnetic fields emitted by mobile phones have received much attention, relatively little is known about the extremely low frequency (ELF) magnetic fields emitted by phones. This paper summarises ELF magnetic flux density measurements on global system for mobile

  20. Developmental effects of extremely low frequency electric and magnetic fields

    International Nuclear Information System (INIS)

    Juutilainen, J.

    2003-01-01

    Developmental effects of extremely low frequency (ELF) electric and magnetic fields are briefly reviewed in this paper. The results of animal studies on ELF electric fields are rather consistent, and do not suggest adverse effects on development. The results of studies on ELF magnetic fields suggest effects on bird embryo development, but not consistently in all studies. Results from experiments with other non-mammalian species have also suggested effects on developmental stability. In mammals, pre-natal exposure to ELF magnetic fields does not result in strong adverse effects on development. The only finding that shows some consistency is increase of minor skeleton alterations. Epidemiological studies do not establish an association between human adverse pregnancy outcomes and maternal exposure to ELF fields, although a few studies have reported increased risks associated with some characteristics of magnetic field exposure. Taken as a whole, the results do not show strong adverse effects on development. However, additional studies on the suggested subtle effects on developmental stability might increase our understanding of the sensitivity of organisms to weak ELF fields. (author)

  1. Study of extremely low frequency electromagnetic fields in infant incubators.

    Science.gov (United States)

    Cermáková, Eleonora

    2003-01-01

    The aim of the work was to present the results of measurements of extremely low frequency electromagnetic fields (ELF EMF), namely the magnetic flux density, inside infant incubators, and to compare these results with the data published by other authors who point out to a possible association between leukemia or other diseases observed in newborns kept in incubators after the birth and the ELF EMF exposure in the incubator. The measured magnetic flux densities were compared with the reference values for this frequency range indicated in the European Union (EU) recommendations. The repeated measurements in incubators were made with a calibrated magnetometer EFA 300 in the frequency range of 5-30 kHz. Effective values of magnetic flux densities of ELF EMF were determined taking account of the reference values. The results of many repeated measurements showing the values of magnetic flux density in modern incubators with plastic supporting frame, were compared with those obtained in old type incubators with iron skeleton. A power frequency of 50 Hz was detected in the incubator and the ELF EMF values were by over two orders lower than the EU reference values. The paper emphasizes the need to take a special care of newborns kept in incubators even if only the sub-reference values are detected. The EU reference values are intended for the adult human population. A baby in an incubator has much smaller dimensions, higher electric conductivity and maybe trigger another mechanism of response to ELF EMF than that indicated in this paper.

  2. WHO's health risk assessment of extremely low frequency electric fields

    International Nuclear Information System (INIS)

    Repacholi, M.H.

    2003-01-01

    The World Health Organization (WHO), the International Commission on Non-Ionizing Radiation Protection (ICNIRP), WHOs scientific collaborating centres (including the UKs National Radiological Protection Board (NRPB) and over 50 participating Member States are participants of WHOs International EMF Project. As part of WHOs health risk assessment process for extremely low frequency fields (ELFs), this workshop was convened by NRPB to assist WHO in evaluating potential health impacts of electrical currents and fields induced by ELF in molecules, cells, tissues and organs of the body. This paper describes the process by which WHO will conduct its health risk assessment. WHO is also trying to provide information on why exposure to ELF magnetic fields seems to be associated with an increased incidence of childhood leukaemia. Are there mechanisms that could lead to this health outcome or does the epidemiological evidence incorporate biases or other factors that need to be further explored? (author)

  3. Effects of extremely low frequency electromagnetic fields on human beings

    International Nuclear Information System (INIS)

    Lilien, J.L.; Dular, P.; Sabariego, R.; Beauvois, V.; Barbier, P.P.; Lorphevre, R.

    2010-01-01

    Since the early seventies, potential health risks from ELF (Extremely Low frequency electromagnetic Fields) exposure (50 Hz) have been extensively treated in the literature (more than 1000 references registered by WHO (World Health Organisation), 2007). After 30 years of worldwide research, the major epidemiological output is the possible modest increased risk (by a factor 2) of childhood leukaemia in case of a long exposure to an ambient magnetic flux density (B-field) higher than 0.4 μT. However, this fact has not been confirmed by in vivo and in vitro studies. Moreover it has not been validated by any adverse health biological mechanisms neither for adults nor for children. International recommendations (ICNIRP, International Commission on Non-Ionising Radiation Protection) are currently, for general public, not to exceed a B-field of 100 μT (50 Hz) and an E-field of 5 kV/m (50 Hz). Herein, a rough overview of typical values of ELF fields will be presented followed by a brief literature survey on childhood leukaemia and ELF The potential carcinogenic effect of ELF would be linked to electrical disturbances in cell behaviour. The major concern linking child-hood leukaemia and ELF is thus to determine the response of bone marrow cells under ELF fields. With that purpose, transmembrane potential will be targeted and linked to the E-field at that level. This paper is three-folded: (1) the electric interactions between ambient ELF fields and the body are studied both qualitatively and quantitatively. Different sources of internal E-field are analysed and classified according to their potential risk; (2) the hypothesis of contact current is detailed; (3) key actions to undertake are highlighted. Based on the current state of the art and some authors' own developments, this paper proposes simple low cost enhancements of private electrical installations in order to annihilate the major source of potential effects of ELF. (authors)

  4. Extremely low frequency magnetic fields and health risks

    Directory of Open Access Journals (Sweden)

    M.I. Buzdugan

    2009-10-01

    Full Text Available In a world abounding in artificially created electromagnetic fields, we consider that a new approach regarding their possible harmful effects on living beings becomes mandatory. The paper reviews briefly the results of some epidemiological studies, the ICNIRP (International Committee on Non-Ionizing Radiation Protection Guidelines and the latest document of the SCENIHR (an organism of the European Commission regarding extremely low frequency (ELF magnetic fields. We are convinced that the best conduct that might be adopted on this matter is the policy of the prudential avoidance. Several examples of possible harmful effects determined by extremely low frequency magnetic fields dedicated to building services engineering in residences are presented, along with several methods of mitigating them.

  5. Cellular studies and interaction mechanisms of extremely low frequency fields

    Science.gov (United States)

    Liburdy, Robert P.

    1995-01-01

    Worldwide interest in the biological effects of ELF (extremely low frequency, level is to identify cellular responses to ELF fields, to develop a dose threshold for such interactions, and with such information to formulate and test appropriate interaction mechanisms. This review is selective and will discuss the most recent cellular studies directed at these goals which relate to power line, sinusoidal ELF fields. In these studies an interaction site at the cell membrane is by consensus a likely candidate, since changes in ion transport, ligand-receptor events such as antibody binding, and G protein activation have been reported. These changes strongly indicate that signal transduction (ST) can be influenced. Also, ELF fields are reported to influence enzyme activation, gene expression, protein synthesis, and cell proliferation, which are triggered by earlier ST events at the cell membrane. The concept of ELF fields altering early cell membrane events and thereby influencing intracellular cell function via the ST cascade is perhaps the most plausible biological framework currently being investigated for understanding ELF effects on cells. For example, the consequence of an increase due to ELF fields in mitogenesis, the final endpoint of the ST cascade, is an overall increase in the probability of mutagenesis and consequently cancer, according to the Ames epigenetic model of carcinogenesis. Consistent with this epigenetic mechanism and the ST pathway to carcinogenesis is recent evidence that ELF fields can alter breast cancer cell proliferation and can act as a copromoter in vitro. The most important dosimetric question being addressed currently is whether the electric (E) or the magnetic (B) field, or if combinations of static B and time-varying B fields represent an exposure metric for the cell. This question relates directly to understanding fundamental interaction mechanisms and to the development of a rationale for ELF dose threshold guidelines. The weight of

  6. Electric and magnetic fields at extremely low frequencies

    International Nuclear Information System (INIS)

    Anderson, L.E.; Kaune, W.T.

    1989-01-01

    Whole-body exposure to extremely low frequency (ELF, 30-300 Hz) electric fields may involve effects related to stimulation of the sensory apparatus at the body surface (hair vibration, possible direct neural stimulation) and effects within the body caused by the flow of current. Magnetic fields may interact predominantly by the induction of internal current flow. Biological effects observed in a living organism may depend on the electric fields induced inside the body, possibly on the magnetic fields penetrating into the body, and on the fields acting at the surface of the body. Areas in which effects have been observed often appear to be associated with the nervous system, including altered neuronal excitability and neurochemical changes, altered hormone levels, changes in behavioural responses, and changes in biological rhythms. No studies unequivocably demonstrate deleterious effects of ELF electric or magnetic field exposure on mammalian reproduction and development, but several suggest such effects. Exposure to ELF electric and magnetic fields does produce biological effects. However, except for fields strong enough to induce current densities above the threshold for the stimulation of nerve tissues, there is no consensus as to whether these effects constitute a hazard to human health. Human data from epidemiological studies, including reported effects on cancer promotion, congenital malformations, reproductive performance and general health, though somewhat suggestive of adverse health effects, are not conclusive. 274 refs, 13 figs, 6 tabs

  7. Extremely low frequency electromagnetic field exposure does not modulate Toll-like receptor signaling in human peripheral blood mononuclear cells

    NARCIS (Netherlands)

    Kleijn, de S.; Bouwens, M.; Verburg-van Kemenade, B.M.L.; Cuppen, J.J.M.; Ferwerda, G.; Hermans, P.

    2011-01-01

    The effects of extremely low frequency electromagnetic fields (ELF-EMF) on human health remain unclear. It has been reported that ELF-EMF may modulate the innate immune response to microorganisms in animal models and mammalian cell-lines. With the recently gained insight in innate immune signaling

  8. Occupational exposure to extremely low-frequency magnetic fields and risk for central nervous system disease

    DEFF Research Database (Denmark)

    Pedersen, Camilla; Poulsen, Aslak Harbo; Rod, Naja Hulvej

    2017-01-01

    Purpose: Evidence of whether exposure to extremely low-frequency magnetic fields (ELF-MF) is related to central nervous system diseases is inconsistent. This study updates a previous study of the incidence of such diseases in a large cohort of Danish utility workers by almost doubling the period...

  9. Extremely low-frequency magnetic fields and risk of childhood leukemia

    DEFF Research Database (Denmark)

    Schüz, Joachim; Dasenbrock, Clemens; Ravazzani, Paolo

    2016-01-01

    Exposure to extremely low-frequency magnetic fields (ELF-MF) was evaluated in an International Agency for Research on Cancer (IARC) Monographs as "possibly carcinogenic to humans" in 2001, based on increased childhood leukemia risk observed in epidemiological studies. We conducted a hazard assess...

  10. Extremely Low Frequency Magnetic Fields Induce Spermatogenic Germ Cell Apoptosis: Possible Mechanism

    Directory of Open Access Journals (Sweden)

    Sang-Kon Lee

    2014-01-01

    Full Text Available The energy generated by an extremely low frequency electromagnetic field (ELF-EMF is too weak to directly induce genotoxicity. However, it is reported that an extremely low frequency magnetic field (ELF-MF is related to DNA strand breakage and apoptosis. The testes that conduct spermatogenesis through a dynamic cellular process involving meiosis and mitosis seem vulnerable to external stress such as heat, MF exposure, and chemical or physical agents. Nevertheless the results regarding adverse effects of ELF-EMF on human or animal reproductive functions are inconclusive. According to the guideline of the International Commission on Non-Ionizing Radiation Protection (ICNIRP; 2010 for limiting exposure to time-varying MF (1 Hz to 100 kHz, overall conclusion of epidemiologic studies has not consistently shown an association between human adverse reproductive outcomes and maternal or paternal exposure to low frequency fields. In animal studies there is no compelling evidence of causal relationship between prenatal development and ELF-MF exposure. However there is increasing evidence that EL-EMF exposure is involved with germ cell apoptosis in testes. Biophysical mechanism by which ELF-MF induces germ cell apoptosis has not been established. This review proposes the possible mechanism of germ cell apoptosis in testes induced by ELF-MF.

  11. Measurement procedure to assess exposure to extremely low-frequency fields: A primary school case study

    International Nuclear Information System (INIS)

    Alonso, A.; Bahillo, A.; De la Rosa, R.; Carrera, A.; Duran, R. J.; Fernandez, P.

    2012-01-01

    How to correctly measure the exposure of general public to extremely low-frequency (ELF) radiation is a key issue for ELF epidemiological studies. This paper proposes a measurement procedure to accurately assess the exposure of people to electric and magnetic field in the frequency band from 5 Hz to 100 kHz in buildings and their premises. As ELF radiation could be particularly harmful to children, the measurement procedure is focused on exposure to ELF in schools. Thus, the students' exposure to ELF fields can be assessed by correlating the ELF measurements to the hours of school activity. In this paper, the measurement protocol was applied to study the ELF exposure on students from Garcia Quintana primary school in Valladolid, Spain. The campaign of measurements for ELF exposure assessment in this primary school was of great interest for the Regional Council of Public Health because of the social alarm generated by the presence of a significant number cancer cases in children. (authors)

  12. Ultra and extremely low frequency electromagnetic fields

    CERN Document Server

    Surkov, Vadim

    2014-01-01

    This book examines how different sources and physical mechanisms affect ULF/ELF effects. It investigates non seismic prediction of impending natural disasters such as earthquakes, volcano eruptions and tsunamis.

  13. Occupational exposure to extremely low frequency magnetic fields and brain tumour risks in the INTEROCC study

    Science.gov (United States)

    Turner, Michelle C; Benke, Geza; Bowman, Joseph D; Figuerola, Jordi; Fleming, Sarah; Hours, Martine; Kincl, Laurel; Krewski, Daniel; McLean, Dave; Parent, Marie-Elise; Richardson, Lesley; Sadetzki, Siegal; Schlaefer, Klaus; Schlehofer, Brigitte; Schüz, Joachim; Siemiatycki, Jack; van Tongeren, Martie; Cardis, Elisabeth

    2014-01-01

    Background Occupational exposure to extremely low frequency magnetic fields (ELF) is a suspected risk factor for brain tumours, however the literature is inconsistent. Few studies have assessed whether ELF in different time windows of exposure may be associated with specific histologic types of brain tumours. This study examines the association between ELF and brain tumours in the large-scale INTEROCC study. Methods Cases of adult primary glioma and meningioma were recruited in seven countries (Australia, Canada, France, Germany, Israel, New Zealand, United Kingdom) between 2000 and 2004. Estimates of mean workday ELF exposure based on a job exposure matrix assigned. Estimates of cumulative exposure, average exposure, maximum exposure, and exposure duration were calculated for the lifetime, and 1–4, 5–9, and 10+ years prior to the diagnosis/reference date. Results There were 3,761 included brain tumour cases (1,939 glioma, 1,822 meningioma) and 5,404 population controls. There was no association between lifetime cumulative ELF exposure and glioma or meningioma risk. However, there were positive associations between cumulative ELF 1–4 years prior to the diagnosis/reference date and glioma (odds ratio (OR) ≥ 90th percentile vs Occupational ELF exposure may play a role in the later stages (promotion and progression) of brain tumourigenesis. PMID:24935666

  14. Extremely low-frequency magnetic fields and survival from childhood acute lymphoblastic leukemia

    DEFF Research Database (Denmark)

    Schüz, J; Grell, K; Kinsey, S

    2012-01-01

    A previous US study reported poorer survival in children with acute lymphoblastic leukemia (ALL) exposed to extremely low-frequency magnetic fields (ELF-MF) above 0.3 μT, but based on small numbers. Data from 3073 cases of childhood ALL were pooled from prospective studies conducted in Canada......, Denmark, Germany, Japan, UK and US to determine death or relapse up to 10 years from diagnosis. Adjusting for known prognostic factors, we calculated hazard ratios (HRs) and 95% confidence intervals (CI) for overall survival and event-free survival for ELF-MF exposure categories and by 0.1 μT increases...

  15. Sensitivity of Pigment Content of Banana and Orchid Tissue Culture Exposed to Extremely Low Frequency Electromagnetic Fiel

    OpenAIRE

    Prihatini, Riry; Saleh, Norihan Mohamad

    2016-01-01

    Natural exposure of extremely low frequency electromagnetic field (ELF-EMF) occurs in the environment and acts as one of the abiotic factors that affect the growth and development of organisms. This study was conducted to determine the effect of ELF-EMF on the tissue cultured banana and slipper orchid chlorophyll content as one of the indicators in measuring plant photosynthetic capacity. Four days old banana (Musa sp. cv. Berangan) corm and seven days old slipper orchid (Paphiopedilum rothsc...

  16. Effect of extremely low frequency electromagnetic fields on growth rate and morphology of bacteria.

    Science.gov (United States)

    Inhan-Garip, Ayse; Aksu, Burak; Akan, Zafer; Akakin, Dilek; Ozaydin, A Nilufer; San, Tangul

    2011-12-01

    To determine the effect of extremely low frequency (bacteria and to determine any morphological changes that might have been caused by ELF-EMF. Six bacterial strains, three Gram-negative and three Gram-positive were subjected to 50 Hz, 0.5 mT ELF-EMF for 6 h. To determine growth rate after ELF-EMF application, bacteria exposed to ELF-EMF for 3 h were collected, transferred to fresh medium and cultured without field application for another 4 h. Growth-rate was determined by optical density (OD) measurements made every hour. Morphological changes were determined with Transmission electron microscopy (TEM) for two gram-negative and two gram-positive strains collected after 3 h of field application. A decrease in growth rate with respect to control samples was observed for all strains during ELF-EMF application. The decrease in growth-rate continued when exposed bacteria were cultured without field application. Significant ultrastructural changes were observed in all bacterial strains, which were seen to resemble the alterations caused by cationic peptides. This study shows that ELF-EMF induces a decrease in growth rate and morphological changes for both Gram-negative and Gram-positive bacteria.

  17. DEVELOPMENT OF EXTREMELY LOW FREQUENCY PASSIVE SHIELDING APPLICATION USING MAGNETIC AQUEOUS SUBSTRATE

    Directory of Open Access Journals (Sweden)

    NOOR ASHIKIN MOHD RASHID

    2016-04-01

    Full Text Available Public concerns on Extremely Low Frequency (ELF Electromagnetic Field (EMF exposure have been elongated since the last few decades. Electrical substations and high tension rooms in commercial buildings were among the contributing factors emanating ELF magnetic fields. This paper discussed various shielding methods conventionally used in mitigating the ELF exposure. Nevertheless, the standard methods were found to be impractical and incapable of meeting currents shielding demands. In response to that, remarkable researches were conducted in effort to invent novel methods which is more convenient and efficient such as magnetic aqueous shielding or paint, textiles and papers shielding. A magnetic aqueous substrate, Manganese Zinc Ferrite was used as shielding material. The magnetic field and flux distribution inside the aqueous magnetic material are evaluated to optimize shielding against ELFEMF exposure, as to mitigate its exposure.

  18. An Investigation on the Effect of Extremely Low Frequency Pulsed Electromagnetic Fields on Human Electrocardiograms (ECGs).

    Science.gov (United States)

    Fang, Qiang; Mahmoud, Seedahmed S; Yan, Jiayong; Li, Hui

    2016-11-23

    For this investigation, we studied the effects of extremely low frequency pulse electromagnetic fields (ELF-PEMF) on the human cardiac signal. Electrocardiograms (ECGs) of 22 healthy volunteers before and after a short duration of ELF-PEMF exposure were recorded. The experiment was conducted under single-blind conditions. The root mean square (RMS) value of the recorded data was considered as comparison criteria. We also measured and analysed four important ECG time intervals before and after ELF-PEMF exposure. Results revealed that the RMS value of the ECG recordings from 18 participants (81.8% of the total participants) increased with a mean value of 3.72%. The increase in ECG voltage levels was then verified by a second experimental protocol with a control exposure. In addition to this, we used hyperbolic T-distributions (HTD) in the analysis of ECG signals to verify the change in the RR interval. It was found that there were small shifts in the frequency-domain signal before and after EMF exposure. This shift has an influence on all frequency components of the ECG signals, as all spectrums were shifted. It is shown from this investigation that a short time exposure to ELF-PEMF can affect the properties of ECG signals. Further study is needed to consolidate this finding and discover more on the biological effects of ELF-PEMF on human physiological processes.

  19. A short-term extremely low frequency electromagnetic field exposure increases circulating leukocyte numbers and affects HPA-axis signaling in mice

    NARCIS (Netherlands)

    Kleijn, de Stan; Ferwerda, Gerben; Wiese, Michelle; Trentelman, Jos; Cuppen, Jan; Kozicz, Tamas; Jager, de Linda; Hermans, Peter W.M.; Kemenade, van Lidy

    2016-01-01

    There is still uncertainty whether extremely low frequency electromagnetic fields (ELF-EMF) can induce health effects like immunomodulation. Despite evidence obtained in vitro, an unambiguous association has not yet been established in vivo. Here, mice were exposed to ELF-EMF for 1, 4, and 24

  20. Artificial excitation of ELF waves with frequency of Schumann resonance

    Science.gov (United States)

    Streltsov, A. V.; Guido, T.; Tulegenov, B.; Labenski, J.; Chang, C.-L.

    2014-11-01

    We report results from the experiment aimed at the artificial excitation of extremely low-frequency (ELF) electromagnetic waves with frequencies corresponding to the frequency of Schumann resonance. Electromagnetic waves with these frequencies can form a standing pattern inside the spherical cavity formed by the surface of the Earth and the ionosphere. In the experiment the ELF waves were excited by heating the ionosphere with X-mode HF electromagnetic waves generated at the High Frequency Active Auroral Research Program (HAARP) facility in Alaska. The experiment demonstrates that heating of the ionosphere can excite relatively large-amplitude electromagnetic waves with frequencies in the range 7.8-8.0 Hz when the ionosphere has a strong F layer, the frequency of the HF radiation is in the range 3.20-4.57 MHz, and the electric field greater than 5 mV/m is present in the ionosphere.

  1. Benign Effect of Extremely Low-Frequency Electromagnetic Field on Brain Plasticity Assessed by Nitric Oxide Metabolism during Poststroke Rehabilitation

    Directory of Open Access Journals (Sweden)

    Natalia Cichoń

    2017-01-01

    Full Text Available Nitric oxide (NO is one of the most important signal molecules, involved in both physiological and pathological processes. As a neurotransmitter in the central nervous system, NO regulates cerebral blood flow, neurogenesis, and synaptic plasticity. The aim of our study was to investigate the effect of the extremely low-frequency electromagnetic field (ELF-EMF on generation and metabolism of NO, as a neurotransmitter, in the rehabilitation of poststroke patients. Forty-eight patients were divided into two groups: ELF-EMF and non-ELF-EMF. Both groups underwent the same 4-week rehabilitation program. Additionally, the ELF-EMF group was exposed to an extremely low-frequency electromagnetic field of 40 Hz, 7 mT, for 15 min/day. Levels of 3-nitrotyrosine, nitrate/nitrite, and TNFα in plasma samples were measured, and NOS2 expression was determined in whole blood samples. Functional status was evaluated before and after a series of treatments, using the Activity Daily Living, Geriatric Depression Scale, and Mini-Mental State Examination. We observed that application of ELF-EMF significantly increased 3-nitrotyrosine and nitrate/nitrite levels, while expression of NOS2 was insignificantly decreased in both groups. The results also show that ELF-EMF treatments improved functional and mental status. We conclude that ELF-EMF therapy is capable of promoting recovery in poststroke patients.

  2. Effects of 100-μT extremely low frequency electromagnetic fields exposure on hematograms and blood chemistry in rats

    International Nuclear Information System (INIS)

    Lai Jinsheng; Zhang Yemao; Zhang Jiangong

    2016-01-01

    The aim of this study was to test whether extremely low frequency electromagnetic fields (ELF EMFs) affect health or not. Here, we constructed a 100-μT/50 Hz electromagnetic field atmosphere. A total of 128 rats were randomly assigned into two groups: the ELF EMF group and the sham group. The ELF EMF group was exposed to 100-μT/50-Hz ELF EMF for 20 h per day for three months; at the same time the other group was exposed to a sham device without ELF EMF. During the three months, the weight was recorded every 2 weeks, and the water intake and food intake of the animals were recorded weekly. The hematologic parameters were detected before and after the exposure, whereas blood chemistry analysis was performed every 4 weeks. The general condition of the exposed rats was not affected by ELF EMF. Compared with the sham group, the hematograms were not significantly altered in the ELF EMF group. Similarly, the blood chemistry (including lipid profile, blood glucose, liver function and renal function of rats) from the ELF EMF group showed no difference compared with rats from the control group during the three months exposure. The present study indicated that short-term exposure of 100-μT/50-Hz ELF EMF may not affect hematograms and blood chemistry in rats. (author)

  3. Extremely low frequency magnetic field measurements in buildings with transformer stations in Switzerland.

    Science.gov (United States)

    Röösli, Martin; Jenni, Daniela; Kheifets, Leeka; Mezei, Gabor

    2011-08-15

    The aim of this study was to evaluate an exposure assessment method that classifies apartments in three exposure categories of extremely low frequency magnetic fields (ELF-MF) based on the location of the apartment relative to the transformer room. We completed measurements in 39 apartments in 18 buildings. In each room of the apartments ELF-MF was concurrently measured with 5 to 6 EMDEX II meters for 10 min. Measured arithmetic mean ELF-MF was 0.59 μT in 8 apartments that were fully adjacent to a transformer room, either directly above the transformer or touching the transformer room wall-to-wall. In apartments that only partly touched the transformer room at corners or edges, average ELF-MF level was 0.14 μT. Average exposure in the remaining apartments was 0.10 μT. Kappa coefficient for exposure classification was 0.64 (95%-CI: 0.45-0.82) if only fully adjacent apartments were considered as highly exposed (>0.4 μT). We found a distinct ELF-MF exposure gradient in buildings with transformer. Exposure classification based on the location of the apartment relative to the transformer room appears feasible. Such an approach considerably reduces effort for exposure assessment and may be used to eliminate selection bias in future epidemiologic studies. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Treatment of Diabetic Foot Ulcers through Systemic Effects of Extremely Low Frequency Electromagnetic Fields

    Science.gov (United States)

    Trejo-Núñez, A. D.; Pérez-Chávez, F.; García-Sánchez, C.; Serrano-Luna, G.; Cañendo-Dorantes, L.

    2008-08-01

    This study was designed to, investigate the healing effects of extremely low frequency electromagnetic fields (ELF-EMF) on diabetic foot ulcers and test two different exposure systems aimed at reducing the ELF-EMF exposure time of patients. In the first system the ELF-EMF were applied to the arm where only 3% of the total blood volume/min circulates at any given time. In the second system the ELF-EMF were applied to the thorax where more than 100% of the total blood volume/minute circulates at any given time. Twenty-six diabetic patients, with superficial neuropathic ulcers unresponsive to medical treatment were included in this preliminary report. In the first group (17 patients), the arm was exposed two hours twice a week to a extremely low frequency electromagnetic field of 0.45-0.9 mTrms, 120 Hz generated inside a solenoid coil of 10.1 cm by 20.5 cm long. In the second group the thorax of 7 patients was exposed 25 minutes twice a week to an electromagnetic field of 0.4-0.85 mTrms, 120 Hz generated in the center of a squared quasi-Helmholtz coil 52 cm by side. One patient was assigned to a placebo configuration of each exposure system with identical appearance as the active equipment but without magnetic field. Patients with deep ulcers, infected ulcers, cancer, or auto-immune disease were excluded. These preliminary results showed that the two exposure systems accelerate the healing process of neuropathic ulcers. Complete healing of the ulcer had a median duration of 90 days in both exposure systems. Therefore thorax exposure where more blood is exposed to ELF-EMF per unit of time was able to reduce 4.8 times the patient treatment time. In those patients assigned to the placebo equipment no healing effects were observed. This study will continue with a parallel, double blind placebo controlled protocol.

  5. A Touch Sensing Technique Using the Effects of Extremely Low Frequency Fields on the Human Body.

    Science.gov (United States)

    Elfekey, Hatem; Bastawrous, Hany Ayad; Okamoto, Shogo

    2016-12-02

    Touch sensing is a fundamental approach in human-to-machine interfaces, and is currently under widespread use. Many current applications use active touch sensing technologies. Passive touch sensing technologies are, however, more adequate to implement low power or energy harvesting touch sensing interfaces. This paper presents a passive touch sensing technique based on the fact that the human body is affected by the surrounding extremely low frequency (ELF) electromagnetic fields, such as those of AC power lines. These external ELF fields induce electric potentials on the human body-because human tissues exhibit some conductivity at these frequencies-resulting in what is called AC hum. We therefore propose a passive touch sensing system that detects this hum noise when a human touch occurs, thus distinguishing between touch and non-touch events. The effectiveness of the proposed technique is validated by designing and implementing a flexible touch sensing keyboard.

  6. Effects of aluminum and extremely low frequency electromagnetic radiation on oxidative stress and memory in brain of mice.

    Science.gov (United States)

    Deng, Yuanxin; Zhang, Yanwen; Jia, Shujie; Liu, Junkang; Liu, Yanxia; Xu, Weiwei; Liu, Lei

    2013-12-01

    This study was aimed to investigate the effect of aluminum and extremely low-frequency magnetic fields (ELF-MF) on oxidative stress and memory of SPF Kunming mice. Sixty male SPF Kunming mice were divided randomly into four groups: control group, ELF-MF group (2 mT, 4 h/day), load aluminum group (200 mg aluminum/kg, 0.1 ml/10 g), and ELF-MF + aluminum group (2 mT, 4 h/day, 200 mg aluminum/kg). After 8 weeks of treatment, the mice of three experiment groups (ELF-MF group, load aluminum group, and ELF-MF + aluminum group) exhibited firstly the learning memory impairment, appearing that the escaping latency to the platform was prolonged and percentage in the platform quadrant was reduced in the Morris water maze (MWM) task. Secondly are the pathologic abnormalities including neuronal cell loss and overexpression of phosphorylated tau protein in the hippocampus and cerebral cortex. On the other hand, the markers of oxidative stress were determined in mice brain and serum. The results showed a statistically significant decrease in superoxide dismutase activity and increase in the levels of malondialdehyde in the ELF-MF group (P < 0.05 or P < 0.01), load aluminum group (P < 0.01), and ELF-MF + aluminum group (P < 0.01). However, the treatment with ELF-MF + aluminum induced no more damage than ELF-MF and aluminum did, respectively. In conclusion, both aluminum and ELF-MF could impact on learning memory and pro-oxidative function in Kunming mice. However, there was no evidence of any association between ELF-MF exposure with aluminum loading.

  7. Activation of Signaling Cascades by Weak Extremely Low Frequency Electromagnetic Fields

    Directory of Open Access Journals (Sweden)

    Einat Kapri-Pardes

    2017-10-01

    Full Text Available Background/Aims: Results from recent studies suggest that extremely low frequency magnetic fields (ELF-MF interfere with intracellular signaling pathways related to proliferative control. The mitogen-activated protein kinases (MAPKs, central signaling components that regulate essentially all stimulated cellular processes, include the extracellular signal-regulated kinases 1/2 (ERK1/2 that are extremely sensitive to extracellular cues. Anti-phospho-ERK antibodies serve as a readout for ERK1/2 activation and are able to detect minute changes in ERK stimulation. The objective of this study was to explore whether activation of ERK1/2 and other signaling cascades can be used as a readout for responses of a variety of cell types, both transformed and non-transformed, to ELF-MF. Methods: We applied ELF-MF at various field strengths and time periods to eight different cell types with an exposure system housed in a tissue culture incubator and followed the phosphorylation of MAPKs and Akt by western blotting. Results: We found that the phosphorylation of ERK1/2 is increased in response to ELF-MF. However, the phosphorylation of ERK1/2 is likely too low to induce ELF-MF-dependent proliferation or oncogenic transformation. The p38 MAPK was very slightly phosphorylated, but JNK or Akt were not. The effect on ERK1/2 was detected for exposures to ELF-MF strengths as low as 0.15 µT and was maximal at ∼10 µT. We also show that ERK1/2 phosphorylation is blocked by the flavoprotein inhibitor diphenyleneiodonium, indicating that the response to ELF-MF may be exerted via NADP oxidase similar to the phosphorylation of ERK1/2 in response to microwave radiation. Conclusions: Our results further indicate that cells are responsive to ELF-MF at field strengths much lower than previously suspected and that the effect may be mediated by NADP oxidase. However, the small increase in ERK1/2 phosphorylation is probably insufficient to affect proliferation and oncogenic

  8. Children’s Personal Exposure Measurements to Extremely Low Frequency Magnetic Fields in Italy

    Directory of Open Access Journals (Sweden)

    Ilaria Liorni

    2016-05-01

    Full Text Available Extremely low frequency magnetic fields (ELF-MFs exposure is still a topic of concern due to their possible impact on children’s health. Although epidemiological studies claimed an evidence of a possible association between ELF-MF above 0.4 μT and childhood leukemia, biological mechanisms able to support a causal relationship between ELF-MF and this disease were not found yet. To provide further knowledge about children’s ELF-MF exposure correlated to children’s daily activities, a measurement study was conducted in Milan (Italy. Eighty-six children were recruited, 52 of whom were specifically chosen with respect to the distance to power lines and built-in transformers to oversample potentially highly exposed children. Personal and bedroom measurements were performed for each child in two different seasons. The major outcomes of this study are: (1 median values over 24-h personal and bedroom measurements were <3 μT established by the Italian law as the quality target; (2 geometric mean values over 24-h bedroom measurements were mostly <0.4 μT; (3 seasonal variations did not significantly influence personal and bedroom measurements; (4 the highest average MF levels were mostly found at home during the day and outdoors; (5 no significant differences were found in the median and geometric mean values between personal and bedroom measurements, but were found in the arithmetic mean.

  9. Efficacy of extremely low-frequency magnetic field in fibromyalgia pain: A pilot study.

    Science.gov (United States)

    Paolucci, Teresa; Piccinini, Giulia; Iosa, Marco; Piermattei, Cristina; de Angelis, Simona; Grasso, Maria Rosaria; Zangrando, Federico; Saraceni, Vincenzo Maria

    2016-01-01

    The purpose of this pilot study was to determine the efficacy of an extremely low-frequency magnetic field (ELF-MF) in decreasing chronic pain in fibromyalgia (FM) patients. Thirty-seven females were recruited and randomized into two groups: one group was first exposed to systemic ELF-MF therapy (100 microtesla, 1 to 80 Hz) and then to sham therapy, and the other group received the opposite sequence of intervention. Pain, FM-related symptoms, and the ability to perform daily tasks were measured using the Visual Analog Scale, Fibromyalgia Impact Questionnaire (FIQ), Fibromyalgia Assessment Scale (FAS), and Health Assessment Questionnaire (HAQ) at baseline, end of first treatment cycle, beginning of second treatment cycle (after 1 mo washout), end of second treatment cycle, and end of 1 mo follow-up. ELF-MF treatment significantly reduced pain, which increased on cessation of therapy but remained significantly lower than baseline levels. Short-term benefits were also observed in FIQ, FAS, and HAQ scores, with less significant effects seen in the medium term. ELF-MF therapy can be recommended as part of a multimodal approach for mitigating pain in FM subjects and improving the efficacy of drug therapy or physiotherapy.

  10. Extremely low frequency electromagnetic field radiation: a preliminary study case in Bangi

    International Nuclear Information System (INIS)

    Roha Tukimin; Wan Nor Liza Mahadi; Mohd Yusof Mohd Ali; Mohd Amirul Nizam Mohd Thari; Mohd Azizi Jali; Ahmad Fadhil Ahmad Sanusi

    2008-08-01

    Extremely low frequency electromagnetic fields radiation is known to be hazardous if amount received is excessive. The primary sources of ELF EMF are from the electricity supply system such as transmission line, substation, transformers and switch gears. Due to limited space, many substations were built very close to the residential area. A study was carried out in the selected houses located in Bangi, Selangor which located close to the TNB substation. The study was made in two conditions, before the area fully occupied and after the resident moved into the house. The aim of the study is for assessing the strength of ELF EMF that emitted by the substation. This study was also conducted to assess the potential exposure received by personnel living in the house. The surveys were carried out using PMM model EHP50A and EMDEX instruments based on standard measurement procedures and protocol recommended by IEEE. Results obtained were compared against the permissible exposure limits recommended by International Commission of Non-Ionising Radiation Protection (ICNIRP).This paper highlights some of the findings at the study site. Results obtained suggest that ELF EMF radiation varies with location and the magnetic fields strength measured near the source of ELF EMF was found to be higher than the normal environment. (Author)

  11. Carcinogenic potential of extremely low frequency magnetic fields: proceedings of a workshop

    International Nuclear Information System (INIS)

    Delpizzo, V.; Keam, D.W.

    1989-02-01

    The debate over the suspected link between Extremely Low Frequency (ELF) magnetic fields and cancer is entering its second decade, but the end is not in sight. The epidemiological evidence is now somewhat stronger, mainly due to the Savitz study of residential exposure and childhood cancer, but far from overwhelming. The results of in-vitro studies are fragmentary, sometimes contradictory and, overall, confusing. Well designed animal studies are virtually non-existent. A plausible biological model has not yet been established. Although scant, the present body of knowledge is very complex encompassing several disciplines and this workshop brought together researchers of vastly different backgrounds. The nine papers presented deal with an overview of ELF and cancer; the biochemistry of processes implicated in ELF carcinogenesis; possible mechanisms of cancer promotion; the status of in-vitro ELF cellular interactions; epidemiological studies, both occupational and residential, and the use of wire coding configurations as indicators of magnetic field exposures in such studies. Discussion follows each paper. Refs., figs., tabs

  12. Assessment of extremely low frequency magnetic field exposure from GSM mobile phones.

    Science.gov (United States)

    Calderón, Carolina; Addison, Darren; Mee, Terry; Findlay, Richard; Maslanyj, Myron; Conil, Emmanuelle; Kromhout, Hans; Lee, Ae-kyoung; Sim, Malcolm R; Taki, Masao; Varsier, Nadège; Wiart, Joe; Cardis, Elisabeth

    2014-04-01

    Although radio frequency (RF) electromagnetic fields emitted by mobile phones have received much attention, relatively little is known about the extremely low frequency (ELF) magnetic fields emitted by phones. This paper summarises ELF magnetic flux density measurements on global system for mobile communications (GSM) mobile phones, conducted as part of the MOBI-KIDS epidemiological study. The main challenge is to identify a small number of generic phone models that can be used to classify the ELF exposure for the different phones reported in the study. Two-dimensional magnetic flux density measurements were performed on 47 GSM mobile phones at a distance of 25 mm. Maximum resultant magnetic flux density values at 217 Hz had a geometric mean of 221 (+198/-104) nT. Taking into account harmonic data, measurements suggest that mobile phones could make a substantial contribution to ELF exposure in the general population. The maximum values and easily available variables were poorly correlated. However, three groups could be defined on the basis of field pattern indicating that manufacturers and shapes of mobile phones may be the important parameters linked to the spatial characteristics of the magnetic field, and the categorization of ELF magnetic field exposure for GSM phones in the MOBI-KIDS study may be achievable on the basis of a small number of representative phones. Such categorization would result in a twofold exposure gradient between high and low exposure based on type of phone used, although there was overlap in the grouping. © 2013 Wiley Periodicals, Inc.

  13. Effects of extremely low-frequency magnetotherapy on proliferation of human dermal fibroblasts.

    Science.gov (United States)

    Pasi, Francesca; Sanna, Samuele; Paolini, Alessandro; Alquati, Marco; Lascialfari, Alessandro; Corti, Maurizio Enrico; Liberto, Riccardo Di; Cialdai, Francesca; Monici, Monica; Nano, Rosanna

    2016-01-01

    Extremely low-frequency electromagnetic fields (ELF-EMFs) applied in magnetotherapy have frequency lower than 100 Hz and magnetic field intensity ranging from 0.1 to 20 mT. For many years, the use of magnetotherapy in clinics has been increasing because of its beneficial effects in many processes, e.g., skin diseases, inflammation and bone disorders. However, the understanding of the microscopic mechanisms governing such processes is still lacking and the results of the studies on the effects of ELF-EMFs are controversial because effects derive from different conditions and from intrinsic responsiveness of different cell types.In the present study, we studied the biological effects of 1.5 h exposure of human dermal fibroblasts to EMFs with frequencies of 5 and 50 Hz and intensity between 0.25 and 1.6 mT. Our data showed that the magnetic treatment did not produce changes in cell viability, but gave evidence of a sizeable decrease in proliferation at 24 h after treatment. In addition, immunofluorescence experiments displayed an increase in tubulin expression that could foreshadow changes in cell motility or morphology. The decrease in proliferation with unchanged viability and increase in tubulin expression could be consistent with the triggering of a transdifferentiation process after the exposure to ELF-EMFs.

  14. Pilot study of extremely low frequency magnetic fields emitted by transformers in dwellings. Social aspects.

    Science.gov (United States)

    Zaryabova, Victoria; Shalamanova, Tsvetelina; Israel, Michel

    2013-06-01

    A large number of epidemiologic studies examining the potential effect of residential exposure to extremely-low frequency (ELF) magnetic fields and childhood leukemia have been published. Two pooled analyses [Ahlbom A, Day N, Feychting M, Roman E, Skinner J, Dockerty J, Linet M, et al. (2000). A pooled analysis of magnetic fields and childhood leukaemia. Br J Cancer. 83(5):692-698; Greenland S, Sheppard AR, Kaune WT, Poole C, Kelsh AM (2000). A pooled analysis of magnetic fields, wire codes, and childhood leukemia. Epidemiology. 11(6):624-634], which included the major epidemiologic studies on ELF magnetic fields and childhood leukemia showed twofold increase in childhood leukemia risk in association with residential ELF exposure above 0.3-0.4 μT. Based on "limited" epidemiologic evidence linking ELF exposure to childhood leukemia and "inadequate evidence" for carcinogenicity of ELF in rodent bioassays, the International Agency for Research on Cancer (IARC) classified ELF magnetic fields as a possible human carcinogen (2B classification) [International Agency for Research on Cancer (IARC) (2002). Non-ionizing radiation, Part 1: Static and extremely low-frequency (ELF) electric and magnetic fields. IARC monographs on the evaluation of carcinogenic risks to humans. Vol. 80. IARC Press: Lyon], confirmed by WHO on the basis of studies published after 2000 [World Health Organization. Extremely low frequency fields. In: 238 Environmental health criteria, Geneva: WHO; 2007]. The analysis of more recent studies of ELF magnetic fields and childhood leukemia had small findings and propose methodological improvements concerning the uncertainties in epidemiological approaches and exposure assessment, bias in selection of controls [Kheifets L, Oksuzyan S (2008). Exposure assessment and other challenges in non-ionizing radiation studies of childhood leukaemia. Radiat Prot Dosimetry. 132(2):139-147]. By the end of 2010, 37 countries had been identified for possible participation

  15. SENSITIVITY OF PIGMENT CONTENT OF BANANA AND ORCHID TISSUE CULTURE EXPOSED TO EXTREMELY LOW FREQUENCY ELECTROMAGNETIC FIEL

    Directory of Open Access Journals (Sweden)

    Riry Prihatini

    2017-01-01

    Full Text Available Natural exposure of extremely low frequency electromagnetic field (ELF-EMF occurs in the environment and acts as one of the abiotic factors that affect the growth and development of organisms. This study was conducted to determine the effect of ELF-EMF on the tissue cultured banana and slipper orchid chlorophyll content as one of the indicators in measuring plant photosynthetic capacity. Four days old banana (Musa sp. cv. Berangan corm and seven days old slipper orchid (Paphiopedilum rothschildianum cultures were exposed to 6 and 12 mT ELF-EMF generated by controllable ELF-EMF built up machine for 0.5, 1, 2 and 4 hours. After exposure, the banana and orchid cultures were incubated at 25° C for 8 and 16 weeks, respectively. The results showed that the ELF-EMF exposure had different effects on banana and slipper orchid cultures though both plant species belong to monocotyledon. The highest increase in chlorophyll content on banana was resulted by the high intensity and long duration of ELF-EMF exposure (12 mT for 4 hours, whereas on slipper orchid the modest and short duration of ELF-EMF exposure produced the most excessive chlorophyll content. Different ELF-EMF exposures (12 mT for 4 hours and 6 mT for 30 minutes had potential to be applied on each plant to improve in vitro plant (banana and slipper orchid, respectively growth. The increased chlorophyll and carotene/xanthophyll content on banana indicated that the banana was more tolerant to ELF-EMF exposure compared to slipper orchid. 

  16. Simulation and Measurement of Through-the-Earth, Extremely Low-Frequency Signals Using Copper-Clad Steel Ground Rods

    OpenAIRE

    Damiano, Nicholas William; Yan, Lincan; Whisner, Bruce; Zhou, Chenming

    2017-01-01

    The underground mining environment can greatly affect radio signal propagation. Understanding how the earth affects signal propagation is a key to evaluating communications systems used during a mine emergency. One type of communication system is through-the-earth, which can utilize extremely low frequencies (ELF). This paper presents the simulation and measurement results of recent National Institute for Occupational Safety and Health (NIOSH) research aimed at investigating current injection...

  17. Extremely low-frequency magnetic fields of transformers and possible biological and health effects.

    Science.gov (United States)

    Sirav, Bahriye; Sezgin, Gaye; Seyhan, Nesrin

    2014-12-01

    Physiological processes in organisms can be influenced by extremely low-frequency (ELF) electromagnetic energy. Biological effect studies have great importance; as well as measurement studies since they provide information on the real exposure situations. In this study, the leakage magnetic fields around a transformer were measured in an apartment building in Küçükçekmece, Istanbul, and the measurement results were evaluated with respect to the international exposure standards. The transformer station was on the bottom floor of a three-floor building. It was found that people living and working in the building were exposed to ELF magnetic fields higher than the threshold magnetic field value of the International Agency for Research on Cancer (IARC). Many people living in this building reported health complaints such as immunological problems of their children. There were child-workers working in the textile factories located in the building. Safe distances or areas for these people should be recommended. Protective measures could be implemented to minimize these exposures. Further residential exposure studies are needed to demonstrate the exposure levels of ELF magnetic fields. Precautions should, therefore, be taken either to reduce leakage or minimize the exposed fields. Shielding techniques should be used to minimize the leakage magnetic fields in such cases.

  18. DNA fragmentation in human fibroblasts under extremely low frequency electromagnetic field exposure

    International Nuclear Information System (INIS)

    Focke, Frauke; Schuermann, David; Kuster, Niels; Schaer, Primo

    2010-01-01

    Extremely low frequency electromagnetic fields (ELF-EMFs) were reported to affect DNA integrity in human cells with evidence based on the Comet assay. These findings were heavily debated for two main reasons; the lack of reproducibility, and the absence of a plausible scientific rationale for how EMFs could damage DNA. Starting out from a replication of the relevant experiments, we performed this study to clarify the existence and explore origin and nature of ELF-EMF induced DNA effects. Our data confirm that intermittent (but not continuous) exposure of human primary fibroblasts to a 50 Hz EMF at a flux density of 1 mT induces a slight but significant increase of DNA fragmentation in the Comet assay, and we provide first evidence for this to be caused by the magnetic rather than the electric field. Moreover, we show that EMF-induced responses in the Comet assay are dependent on cell proliferation, suggesting that processes of DNA replication rather than the DNA itself may be affected. Consistently, the Comet effects correlated with a reduction of actively replicating cells and a concomitant increase of apoptotic cells in exposed cultures, whereas a combined Fpg-Comet test failed to produce evidence for a notable contribution of oxidative DNA base damage. Hence, ELF-EMF induced effects in the Comet assay are reproducible under specific conditions and can be explained by minor disturbances in S-phase processes and occasional triggering of apoptosis rather than by the generation of DNA damage.

  19. DNA fragmentation in human fibroblasts under extremely low frequency electromagnetic field exposure

    Energy Technology Data Exchange (ETDEWEB)

    Focke, Frauke; Schuermann, David [Institute of Biochemistry and Genetics, Department of Biomedicine, University of Basel, Mattenstrasse 28, CH-4058 Basel (Switzerland); Kuster, Niels [IT' IS Foundation, Zeughausstrasse 43, CH-8004 Zurich (Switzerland); Schaer, Primo, E-mail: primo.schaer@unibas.ch [Institute of Biochemistry and Genetics, Department of Biomedicine, University of Basel, Mattenstrasse 28, CH-4058 Basel (Switzerland)

    2010-01-05

    Extremely low frequency electromagnetic fields (ELF-EMFs) were reported to affect DNA integrity in human cells with evidence based on the Comet assay. These findings were heavily debated for two main reasons; the lack of reproducibility, and the absence of a plausible scientific rationale for how EMFs could damage DNA. Starting out from a replication of the relevant experiments, we performed this study to clarify the existence and explore origin and nature of ELF-EMF induced DNA effects. Our data confirm that intermittent (but not continuous) exposure of human primary fibroblasts to a 50 Hz EMF at a flux density of 1 mT induces a slight but significant increase of DNA fragmentation in the Comet assay, and we provide first evidence for this to be caused by the magnetic rather than the electric field. Moreover, we show that EMF-induced responses in the Comet assay are dependent on cell proliferation, suggesting that processes of DNA replication rather than the DNA itself may be affected. Consistently, the Comet effects correlated with a reduction of actively replicating cells and a concomitant increase of apoptotic cells in exposed cultures, whereas a combined Fpg-Comet test failed to produce evidence for a notable contribution of oxidative DNA base damage. Hence, ELF-EMF induced effects in the Comet assay are reproducible under specific conditions and can be explained by minor disturbances in S-phase processes and occasional triggering of apoptosis rather than by the generation of DNA damage.

  20. Anti-proliferative effect of extremely low frequency electromagnetic field on preneoplastic lesions formation in the rat liver

    International Nuclear Information System (INIS)

    Jiménez-García, Mónica Noemí; Arellanes-Robledo, Jaime; Aparicio-Bautista, Diana Ivette; Rodríguez-Segura, Miguel Ángel; Villa-Treviño, Saúl; Godina-Nava, Juan José

    2010-01-01

    Recently, extremely low frequency electromagnetic fields (ELF-EMF) have been studied with great interest due to their possible effects on human health. In this study, we evaluated the effect of 4.5 mT - 120 Hz ELF-EMF on the development of preneoplastic lesions in experimental hepatocarcinogenesis. Male Fischer-344 rats were subjected to the modified resistant hepatocyte model and were exposed to 4.5 mT - 120 Hz ELF-EMF. The effects of the ELF-EMF on hepatocarcinogenesis, apoptosis, proliferation and cell cycle progression were evaluated by histochemical, TUNEL assay, caspase 3 levels, immunohistochemical and western blot analyses. The application of the ELF-EMF resulted in a decrease of more than 50% of the number and the area of γ-glutamyl transpeptidase-positive preneoplastic lesions (P = 0.01 and P = 0.03, respectively) and glutathione S-transferase placental expression (P = 0.01). The number of TUNEL-positive cells and the cleaved caspase 3 levels were unaffected; however, the proliferating cell nuclear antigen, Ki-67, and cyclin D1 expression decreased significantly (P ≤ 0.03), as compared to the sham-exposure group. The application of 4.5 mT - 120 Hz ELF-EMF inhibits preneoplastic lesions chemically induced in the rat liver through the reduction of cell proliferation, without altering the apoptosis process

  1. Anti-proliferative effect of extremely low frequency electromagnetic field on preneoplastic lesions formation in the rat liver

    Directory of Open Access Journals (Sweden)

    Villa-Treviño Saúl

    2010-04-01

    Full Text Available Abstract Background Recently, extremely low frequency electromagnetic fields (ELF-EMF have been studied with great interest due to their possible effects on human health. In this study, we evaluated the effect of 4.5 mT - 120 Hz ELF-EMF on the development of preneoplastic lesions in experimental hepatocarcinogenesis. Methods Male Fischer-344 rats were subjected to the modified resistant hepatocyte model and were exposed to 4.5 mT - 120 Hz ELF-EMF. The effects of the ELF-EMF on hepatocarcinogenesis, apoptosis, proliferation and cell cycle progression were evaluated by histochemical, TUNEL assay, caspase 3 levels, immunohistochemical and western blot analyses. Results The application of the ELF-EMF resulted in a decrease of more than 50% of the number and the area of γ-glutamyl transpeptidase-positive preneoplastic lesions (P = 0.01 and P = 0.03, respectively and glutathione S-transferase placental expression (P = 0.01. The number of TUNEL-positive cells and the cleaved caspase 3 levels were unaffected; however, the proliferating cell nuclear antigen, Ki-67, and cyclin D1 expression decreased significantly (P ≤ 0.03, as compared to the sham-exposure group. Conclusion The application of 4.5 mT - 120 Hz ELF-EMF inhibits preneoplastic lesions chemically induced in the rat liver through the reduction of cell proliferation, without altering the apoptosis process.

  2. The effects of extremely low frequency magnetic fields on mutation induction in mice

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, James W. [Department of Genetics, University of Leicester, Leicester LE1 7RH (United Kingdom); Haines, Jackie; Sienkiewicz, Zenon [Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, Didcot, Oxfordshire OX11 0RQ (United Kingdom); Dubrova, Yuri E., E-mail: yed2@le.ac.uk [Department of Genetics, University of Leicester, Leicester LE1 7RH (United Kingdom)

    2015-03-15

    Highlights: • The effects of 50 Hz magnetic fields on mutation induction in mice were analyzed. • The frequency of ESTR mutation was established in sperm and blood. • Exposure to 10–300 μT for 2 and 15 h did not result in mutation induction. • Mutagenic effects of 50 Hz magnetic fields are likely to be negligible. - Abstract: The growing human exposure to extremely low frequency (ELF) magnetic fields has raised a considerable concern regarding their genotoxic effects. The aim of this study was to evaluate the in vivo effects of ELF magnetic fields irradiation on mutation induction in the germline and somatic tissues of male mice. Seven week old BALB/c × CBA/Ca F{sub 1} hybrid males were exposed to 10, 100 or 300 μT of 50 Hz magnetic fields for 2 or 15 h. Using single-molecule PCR, the frequency of mutation at the mouse Expanded Simple Tandem Repeat (ESTR) locus Ms6-hm was established in sperm and blood samples of exposed and matched sham-treated males. ESTR mutation frequency was also established in sperm and blood samples taken from male mice exposed to 1 Gy of acute X-rays. The frequency of ESTR mutation in DNA samples extracted from blood of mice exposed to magnetic fields did not significantly differ from that in sham-treated controls. However, there was a marginally significant increase in mutation frequency in sperm but this was not dose-dependent. In contrast, acute exposure X-rays led to significant increases in mutation frequency in sperm and blood of exposed males. The results of our study suggest that, within the range of doses analyzed here, the in vivo mutagenic effects of ELF magnetic fields are likely to be minor if not negligible.

  3. The effects of extremely low frequency magnetic fields on mutation induction in mice

    International Nuclear Information System (INIS)

    Wilson, James W.; Haines, Jackie; Sienkiewicz, Zenon; Dubrova, Yuri E.

    2015-01-01

    Highlights: • The effects of 50 Hz magnetic fields on mutation induction in mice were analyzed. • The frequency of ESTR mutation was established in sperm and blood. • Exposure to 10–300 μT for 2 and 15 h did not result in mutation induction. • Mutagenic effects of 50 Hz magnetic fields are likely to be negligible. - Abstract: The growing human exposure to extremely low frequency (ELF) magnetic fields has raised a considerable concern regarding their genotoxic effects. The aim of this study was to evaluate the in vivo effects of ELF magnetic fields irradiation on mutation induction in the germline and somatic tissues of male mice. Seven week old BALB/c × CBA/Ca F 1 hybrid males were exposed to 10, 100 or 300 μT of 50 Hz magnetic fields for 2 or 15 h. Using single-molecule PCR, the frequency of mutation at the mouse Expanded Simple Tandem Repeat (ESTR) locus Ms6-hm was established in sperm and blood samples of exposed and matched sham-treated males. ESTR mutation frequency was also established in sperm and blood samples taken from male mice exposed to 1 Gy of acute X-rays. The frequency of ESTR mutation in DNA samples extracted from blood of mice exposed to magnetic fields did not significantly differ from that in sham-treated controls. However, there was a marginally significant increase in mutation frequency in sperm but this was not dose-dependent. In contrast, acute exposure X-rays led to significant increases in mutation frequency in sperm and blood of exposed males. The results of our study suggest that, within the range of doses analyzed here, the in vivo mutagenic effects of ELF magnetic fields are likely to be minor if not negligible

  4. Weak Static and Extremely Low Frequency Magnetic Fields Affect In Vitro Pollen Germination

    Directory of Open Access Journals (Sweden)

    Lucietta Betti

    2011-01-01

    Full Text Available This study concerns the effects of a weak static magnetic field (MF at 10 μT oriented downward, combined with a 16-Hz sinusoidal MF (10 μT, on in vitro pollen germination of kiwifruit (Actinidia deliciosa. Extremely low frequency magnetic field (ELF-MF exposure was carried out by a signal generator unit connected to a copper wire solenoid, inside which samples where placed. Two different kinds of treatment were performed: direct and indirect. In the direct treatment, pollen samples were directly exposed during rehydration, germination, or both. In the indirect treatment, the pollen growth medium was prepared with water aliquots (at standard temperature of 20°C and pH = 6.74 that were exposed before use for 8 or 24 h. The main purpose of our research was to identify a biological marker (in vitro pollen germination in a stressing growth medium without Ca2+ susceptible to the effects of direct or indirect ELF-MF exposure. The working variable was the pollen germination rate, as detected blind after 3 h 30 min by an Axioplan microscope. A directionally consistent recovery of germination percentage was observed both for direct exposure (during germination and both rehydration and germination phases and water-mediated exposure (with water exposed for 24 h and immediately used. Our results suggest that the ELF-MF treatment might partially remove the inhibitory effect caused by the lack of Ca2+ in the culture medium, inducing a release of internal Ca2+ stored in the secretory vesicles of pollen plasma membrane. Although preliminary, findings seem to indicate the in vitro pollen performance as adequate to study the effects of ELF-MFs on living matter.

  5. Neuronal cellular responses to extremely low frequency electromagnetic field exposure: implications regarding oxidative stress and neurodegeneration.

    Directory of Open Access Journals (Sweden)

    Marcella Reale

    Full Text Available Neurodegenerative diseases comprise both hereditary and sporadic conditions characterized by an identifying progressive nervous system dysfunction and distinctive neuopathophysiology. The majority are of non-familial etiology and hence environmental factors and lifestyle play key roles in their pathogenesis. The extensive use of and ever increasing worldwide demand for electricity has stimulated societal and scientific interest on the environmental exposure to low frequency electromagnetic fields (EMFs on human health. Epidemiological studies suggest a positive association between 50/60-Hz power transmission fields and leukemia or lymphoma development. Consequent to the association between EMFs and induction of oxidative stress, concerns relating to development of neurodegenerative diseases, such as Alzheimer disease (AD, have been voiced as the brain consumes the greatest fraction of oxygen and is particularly vulnerable to oxidative stress. Exposure to extremely low frequency (ELF-EMFs are reported to alter animal behavior and modulate biological variables, including gene expression, regulation of cell survival, promotion of cellular differentiation, and changes in cerebral blood flow in aged AD transgenic mice. Alterations in inflammatory responses have also been reported, but how these actions impact human health remains unknown. We hence evaluated the effects of an electromagnetic wave (magnetic field intensity 1 mT; frequency, 50-Hz on a well-characterized immortalized neuronal cell model, human SH-SY5Y cells. ELF-EMF exposure elevated the expession of NOS and O2(-, which were countered by compensatory changes in antioxidant catylase (CAT activity and enzymatic kinetic parameters related to CYP-450 and CAT activity. Actions of ELF-EMFs on cytokine gene expression were additionally evaluated and found rapidly modified. Confronted with co-exposure to H2O2-induced oxidative stress, ELF-EMF proved not as well counteracted and resulted in a

  6. Extremely low-frequency magnetic exposure appears to have no effect on pathogenesis of Alzheimer's disease in aluminum-overloaded rat.

    Directory of Open Access Journals (Sweden)

    Cheng Zhang

    Full Text Available OBJECTIVE: Extremely low-frequency magnetic field (ELF-MF has been reported to be of potential pathogenetic relevance to Alzheimer's disease (AD for years. However, evidence confirming this function remains inconclusive. Chronic Al treatment has been identified as a contributing factor to cognitive function impairment in AD. This study aims to examine whether or not ELF-MF and Al have synergistic effects toward AD pathogenesis by investigating the effects of ELF-MF with or without chronic Al treatment on SD rats. METHODS: Sprague-Dawley (SD rats were subjected one of the following treatments: sham (control group, oral Al (Al group, ELF-MF (100 µT at 50 Hz with oral Al (MF+Al group, or ELF-MF (100 µT at 50 Hz without oral Al (MF group. RESULTS: After 12 wk of treatment, oral Al treatment groups (Al and MF+Al groups showed learning and memory impairment as well as morphological hallmarks, including neuronal cell loss and high density of amyloid-β (Aβ in the hippocampus and cerebral cortex. ELF-MF without Al treatment showed no significant effect on AD pathogenesis. ELF-MF+Al treatment induced no more damage than Al treatment did. CONCLUSIONS: Our results showed no evidence of any association between ELF-MF exposure (100 µT at 50 Hz and AD, and ELF-MF exposure does not influence the pathogenesis of AD induced by Al overload.

  7. Examples of extremely low-frequency magnetic fields in a Finnish metro station

    International Nuclear Information System (INIS)

    Korpinen, L.; Sydaenheimo, L.; Laehdetie, A.; Amundin, A.; Piippo, H.

    2015-01-01

    The aim of this pilot study was to present examples of extremely low-frequency (ELF) magnetic fields in a Finnish metro station. The metro trains are powered by 750 V DC voltage supplied through a conductor rail next to the running rails. We measured magnetic fields with a magnetic field meter MFM 3000 in 17 cases when a train was leaving the platform in the same metro station. The maximum measured magnetic field was 5400 nT (at 1 m height and 4.3 m from the conductor rail). The magnetic field stayed at this level for a very short time after the metro left the platform. It is possible that there are also DC magnetic fields near the metro as the train leaves the station because the trains are powered by DC voltage. Therefore, it is also important to measure DC fields and DC currents in the future. (authors)

  8. The effect of extremely low frequency electromagnetic fields on the chromosomal instability in bleomycin treated fibroblast cells

    International Nuclear Information System (INIS)

    Cho, Yoon Hee; Kim, Yang Jee; Lee, Joong Won; Kim, Gye Eun; Chung, Hai Won

    2008-01-01

    In order to determine the effect of Extremely Low Frequency ElectroMagnetic Fields (ELF-EMF) on the frequency of MicroNuclei (MN), aneuploidy and chromosomal rearrangement induced by BLeoMycin (BLM) in human fibroblast cells, a 60 Hz ELF-EMF of 0.8 mT field strength was applied either alone or with BLM throughout the culture period and a micronucleus-centromere assay was performed. Our results indicate that the frequencies of MN, aneuploidy and chromosomal rearrangement induced by BLM increased in a dose-dependent manner. The exposure of cells to 0.8 mT ELF-EMF followed by BLM exposure for 3 hours led to significant increases in the frequencies of MN and aneuploidy compared to BLM treatment for 3 hours alone (p<0.05), but no significant difference was observed between field exposed and sham exposed control cells. The obtained results suggest that low density ELF-EMF could act as enhancer of the initiation process of BLM rather than as an initiator of mutagenic effects in human fibroblast

  9. [Effect of extremely low frequency magnetic field on glutathione in rat muscles].

    Science.gov (United States)

    Ciejka, Elzbieta; Jakubowska, Ewa; Zelechowska, Paulina; Huk-Kolega, Halina; Kowalczyk, Agata; Goraca, Anna

    2014-01-01

    Free radicals (FR) are atoms, molecules or their fragments. Their excess leads to the development of oxidizing stress, the cause of many neoplastic, neurodegenerative and inflammatory diseases, and aging of the organism. Industrial pollution, tobacco smoke, ionizing radiation, ultrasound and magnetic field are the major FR exogenous sources. The low frequency magnetic field is still more commonly applied in the physical therapy. The aim of the presented study was to evaluate the effect of extremely low frequency magnetic field used in the magnetotherapy on the level of total glutathione, oxidized and reduced, and the redox state of the skeletal muscle cells, depending on the duration of exposure to magnetic field. The male rats, weight of 280-300 g, were randomly devided into 3 experimental groups: controls (group I) and treatment groups exposed to extremely low frequency magnetic field (ELF-MF) (group II exposed to 40 Hz, 7 mT for 0.5 h/day for 14 days and group III exposed to 40 Hz, 7 mT for 1 h/day for 14 days). Control rats were kept in a separate room not exposed to extremely low frequency magnetic field. Immediately after the last exposure, part of muscles was taken under pentobarbital anesthesia. Total glutathione, oxidized and reduced, and the redox state in the muscle tissue of animals were determined after exposure to magnetic fields. Exposure to low magnetic field: 40 Hz, 7 mT for 30 min/day and 60 min/day for 2 weeks significantly increased the total glutathione levels in the skeletal muscle compared to the control group (p magnetic therapy plays an important role in the development of adaptive mechanisms responsible for maintaining the oxidation-reduction balance in the body and depends on exposure duration.

  10. Effects of extremely low frequency electromagnetic field on the health of workers in automotive industry.

    Science.gov (United States)

    Liu, Xin; Zhao, Longyu; Yu, Duo; Ma, Shumei; Liu, Xiaodong

    2013-12-01

    To observe the effects of extremely low frequency electromagnetic fields (ELF-EMFs) in automotive industry on occupational workers. A total of 704 workers were investigated, and 374 workers were chosen and divided into two groups (control group and exposure group) according to the inclusive criteria, namely male with age 20-40 years old and ≥ 2 years of exposure. The intensities of ELF-EMFs and noise were detected with EFA-300 Field Analyzer (Narda company, Pfullingen, Germany) and AWA5610D integrating sound level meter (Hangzhou Aihua Instruments Co., Ltd, Hangzhou, China), respectively. Survey data were collected by questionnaire, and the physical check-up was done in hospital. All the data were input into SPSS17.0 software (SPSS Inc, Chicago, USA), and the appropriate statistic analyses were carried out. The intensity of EMFs in exposure group was significantly higher than that in control group (p 0.05). The survey data collected by questionnaires showed that the symptoms of loss of hair in exposure group were significantly different as compared with that in control group (p effects on the nervous, cardiovascular, liver, and hematology system of workers.

  11. Effect of extremely low frequency electromagnetic field on brain histopathology of Caspian Sea Cyprinus carpio.

    Science.gov (United States)

    Samiee, Farzaneh; Samiee, Keivandokht

    2017-01-01

    There is limited research on the effect of electromagnetic field on aquatic organisms, especially freshwater fish species. This study was conducted to evaluate the effect of extremely low frequency electromagnetic field (ELF-EMF) (50 Hz) exposure on brain histopathology of Cyprinus carpio, one of the important species of Caspian Sea with significant economic value. A total of 200 healthy fish were used in this study. They were classified randomly in two groups: sham-exposed group and experimental group, which were exposed to five different magnetic field intensities (0.1, 1, 3, 5, and 7 mT) at two different exposure times (0.5 and 1 h). Histologic results indicate that exposure of C. carpio to artificial ELF-EMF caused severe histopathological changes in the brain at field intensities ≥3 mT leading to brain necrosis. Field intensity and duration of exposure were key parameters in induction of lesion in the brain. Further studies are needed to elucidate exact mechanism of EMF exposure on the brain.

  12. Occupational Exposure Assessment of Tehran Metro Drivers to Extremely Low Frequency Magnetic Fields

    Directory of Open Access Journals (Sweden)

    mohammad reza Monazzam

    2016-03-01

    Full Text Available Introduction: Occupational exposure to Extremely Low Frequency Magnetic Fields (ELF-MFs in train drivers is an integral part of the driving task and creates concern about driving jobs. The present study was designed to investigate the occupational exposure of Tehran train drivers to extremely low frequency magnetic fields. Methods: In order to measure the driver’s exposure, from each line, a random sample in AC and DC type trains was selected and measurements were done according to the IEEE std 644-1994 using a triple axis TES-394 device. Train drivers were then compared with national occupational exposure limit guidelines. Results: The maximum and minimum mean exposure was found in AC external city trains (1.2±1.5 μT and DC internal city trains (0.31±0.2 μT, respectively. The maximum and minimum exposure was 9 μT and 0.08 μT in AC trains of line 5, respectively. In the internal train line, maximum and minimum values were 5.4 μT and 0.08 μT in AC trains. Conclusions: In none of the exposure scenarios in different trains, the exposure exceeded the national or international occupational exposure limit guidelines. However, this should not be the basis of safety in these fields

  13. Exposure estimates based on broadband elf magnetic field measurements versus the ICNIRP multiple frequency rule

    International Nuclear Information System (INIS)

    Paniagua, Jesus M.; Rufo, Montana; Jimenez, Antonio; Pachon, Fernando T.; Carrero, Julian

    2015-01-01

    The evaluation of exposure to extremely low-frequency (ELF) magnetic fields using broadband measurement techniques gives satisfactory results when the field has essentially a single frequency. Nevertheless, magnetic fields are in most cases distorted by harmonic components. This work analyses the harmonic components of the ELF magnetic field in an outdoor urban context and compares the evaluation of the exposure based on broadband measurements with that based on spectral analysis. The multiple frequency rule of the International Commission on Non-ionizing Radiation Protection (ICNIRP) regulatory guidelines was applied. With the 1998 ICNIRP guideline, harmonics dominated the exposure with a 55 % contribution. With the 2010 ICNIRP guideline, however, the primary frequency dominated the exposure with a 78 % contribution. Values of the exposure based on spectral analysis were significantly higher than those based on broadband measurements. Hence, it is clearly necessary to determine the harmonic components of the ELF magnetic field to assess exposure in urban contexts. (authors)

  14. Simulation and Measurement of Through-the-Earth, Extremely Low-Frequency Signals Using Copper-Clad Steel Ground Rods.

    Science.gov (United States)

    Damiano, Nicholas William; Yan, Lincan; Whisner, Bruce; Zhou, Chenming

    2017-01-01

    The underground mining environment can greatly affect radio signal propagation. Understanding how the earth affects signal propagation is a key to evaluating communications systems used during a mine emergency. One type of communication system is through-the-earth, which can utilize extremely low frequencies (ELF). This paper presents the simulation and measurement results of recent National Institute for Occupational Safety and Health (NIOSH) research aimed at investigating current injection at ELF, and in particular, ground contact impedance. Measurements were taken at an outside surface testing location. The results obtained from modeling and measurement are characterized by electrode impedance, and the voltage received between two distant electrodes. This paper concludes with a discussion of design considerations found to affect low-frequency communication systems utilizing ground rods to inject a current into the earth.

  15. Extremely low frequencies. Health effects of extremely low frequency electromagnetic fields. Opinion of the Afsset. Collective expertise report

    International Nuclear Information System (INIS)

    Bounouh, Alexandre; Brugere, Henri; Clavel, Jacqueline; Febvre, Pascal; Lagroye, Isabelle; Vecchia, Paolo; Dore, Jean-Francois; Anfosso-Ledee, Fabienne; Berengier, Michel; Cesarini, Jean-Pierre; Cohen, Jean-Claude; Planton, Serge; Courant, Daniel; Tardif, Francois; Couturier, Frederic; Debouzy, Jean-Claude; El Khatib, Aicha; Flahaut, Emmanuel; Gaffet, Eric; Hours, Martine; Lambert, Jacques; Vallet, Michel; Job, Agnes; Labeyrie, Antoine; Laurier, Dominique; Le Bihan, Olivier; Lepoutre, Philippe; Marchal, Didier; Moch, Annie; Pirard, Philipe; Rumeau, Michel; De Seze, Rene; Attia, Dina; Merckel, Olivier; Fite, Johanna; Guichard, Alexandra; Saihi, Myriam; Guitton, Sophie; Saddoki, Sophia

    2010-03-01

    This report aims at proposing a synthesis of works of international expertise on the health effect of extremely low frequency electromagnetic fields, at performing a methodological analysis of the 'Expers' study (a study on the exposure of individuals), at performing a methodological analysis of a study performed by the Criirem in the western part of France, at assessing the contribution of different equipment and situations to the exposure of population to extremely-low-frequency electromagnetic fields, at making recommendations and proposals for a better assessment of the exposure level, and at proposing topics of investigation and research to improve knowledge on these issues. The report recalls the context, scope and modalities of the study, gives an overview of generalities on electromagnetic fields (nature, physical values, electromagnetic spectrum, artificial and natural electromagnetic field sources, exposure threshold values and regulatory context), addresses the assessment of exposure (notion of exposure, exposure assessment methods, analysis of available data, analysis of recent or current studies), gives an overview of biological and health effects of these electromagnetic fields (methodological aspects, interaction between fields and biological tissues, synthesis of the international expertise on health impacts). Recommendations are formulated

  16. The Biological Effect of Extremely Low Frequency Electromagnetic Fields and Vibrations on Barley Seed Hydration and Germination

    Directory of Open Access Journals (Sweden)

    Armine Amyan

    2004-01-01

    Full Text Available The changes of wet and dry weights and germination of barley seed in different periods of its swelling in nontreated (control, extremely low frequency electromagnetic fields (ELF EMF –treated, and extremely low frequency vibrations (ELFV–treated cold (4°C and warm (20°C distilled water (DW were studied. The metabolic-dependent seed hydration, dry weight dissolving, germination, and water binding in seed were modulated by preliminary EMF- and ELFV-treated DW. Frequency “windows” for the effect of EMF and ELFV on seed hydration, solubility, water binding in seed, and germination were discovered. These “windows” were different for EMF and ELFV, as well as in various phases of seed swelling. It is suggested that EMF-induced water structure modification has a different biological effect on the process of seed hydration, solubility, water binding in seed, and germination compared to ELFV.

  17. Extremely Low-Frequency Electromagnetic Fields Promote In Vitro Neuronal Differentiation and Neurite Outgrowth of Embryonic Neural Stem Cells via Up-Regulating TRPC1

    Science.gov (United States)

    Ma, Qinlong; Chen, Chunhai; Deng, Ping; Zhu, Gang; Lin, Min; Zhang, Lei; Xu, Shangcheng; He, Mindi; Lu, Yonghui; Duan, Weixia; Pi, Huifeng; Cao, Zhengwang; Pei, Liping; Li, Min; Liu, Chuan; Zhang, Yanwen; Zhong, Min; Zhou, Zhou; Yu, Zhengping

    2016-01-01

    Exposure to extremely low-frequency electromagnetic fields (ELF-EMFs) can enhance hippocampal neurogenesis in adult mice. However, little is focused on the effects of ELF-EMFs on embryonic neurogenesis. Here, we studied the potential effects of ELF-EMFs on embryonic neural stem cells (eNSCs). We exposed eNSCs to ELF-EMF (50 Hz, 1 mT) for 1, 2, and 3 days with 4 hours per day. We found that eNSC proliferation and maintenance were significantly enhanced after ELF-EMF exposure in proliferation medium. ELF-EMF exposure increased the ratio of differentiated neurons and promoted the neurite outgrowth of eNSC-derived neurons without influencing astrocyes differentiation and the cell apoptosis. In addition, the expression of the proneural genes, NeuroD and Ngn1, which are crucial for neuronal differentiation and neurite outgrowth, was increased after ELF-EMF exposure. Moreover, the expression of transient receptor potential canonical 1 (TRPC1) was significantly up-regulated accompanied by increased the peak amplitude of intracellular calcium level induced by ELF-EMF. Furthermore, silencing TRPC1 expression eliminated the up-regulation of the proneural genes and the promotion of neuronal differentiation and neurite outgrowth induced by ELF-EMF. These results suggest that ELF-EMF exposure promotes the neuronal differentiation and neurite outgrowth of eNSCs via up-regulation the expression of TRPC1 and proneural genes (NeuroD and Ngn1). These findings also provide new insights in understanding the effects of ELF-EMF exposure on embryonic brain development. PMID:26950212

  18. Case-Control Study on Occupational Exposure to Extremely Low-Frequency Electromagnetic Fields and the Association with Meningioma

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    Michael Carlberg

    2018-01-01

    Full Text Available Objective. Exposure to extremely low-frequency electromagnetic fields (ELF-EMF was in 2002 classified as a possible human carcinogen, Group 2B, by the International Agency for Research on Cancer at WHO based on an increased risk for childhood leukemia. In case-control studies on brain tumors during 1997–2003 and 2007–2009 we assessed lifetime occupations in addition to exposure to different agents. The INTEROCC ELF-EMF Job-Exposure Matrix was used for associating occupations with ELF-EMF exposure (μT with meningioma. Cumulative exposure (μT-years, average exposure (μT, and maximum exposed job (μT were calculated. Results. No increased risk for meningioma was found in any category. For cumulative exposure in the highest exposure category 8.52+ μT years odds ratio (OR = 0.9, 95% confidence interval (CI = 0.7–1.2, and p linear trend = 0.45 were calculated. No statistically significant risks were found in different time windows. Conclusion. In conclusion occupational ELF-EMF was not associated with an increased risk for meningioma.

  19. Influences of extremely low frequency magnetic fields on mineral ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-05

    Nov 5, 2008 ... African Journal of Biotechnology Vol. 7 (21), pp. ... 1Department of Pediatrics Dentistry, Faculty of Dentistry, University of Dicle. Diyarbakir ... the research community to define more precisely the physical ... clinical effects (Brown et al., 2004). ... group of rats was ELF Magnetic Field-or sham-exposed, i.e., the.

  20. Oxidative and antioxidative responses in submandibular and parotid glands of rats exposed to long-term extremely low frequency magnetic field

    Directory of Open Access Journals (Sweden)

    Mehmet Akdağ

    2014-06-01

    Full Text Available Background: Some epidemiologic and laboratory studies have suggested a possible associations between exposure to extremely low frequency magnetic field (ELF-MF and cancer. However, it is not known underlying mechanisms of this interaction. The aim of the study was to investigate the possible oxidative damage induced by long-term ELF-MF exposure on submandibular and parotis glands of rats. Methods: Rats in the experimental group were exposed to 100 and 500 µT ELF-MF (2 h/day, 7 days/week, for 10 months corresponding to exposure levels that are considered safe for humans. The same experimental procedures were applied to the sham group, but the ELF generator was turned off. The levels of catalase (CAT, malondialdehyde (MDA, myeloperoxidase (MPO, total antioxidative capacity (TAC, total oxidant status (TOS, and oxidative stress index (OSI were measured in rat submandibular and parotis gland. Results: Although some oxidative and antioxidative parameters of submandibular gland were altered by ELF-100 and ELF-500 exposure groups, these changes were not statistically significant ( p >0.05. However, a decrease observed in CAT levels of parotid gland in both the ELF-100 and ELF-500 exposure groups (p0.05. Conclusions: Our results showed that long-term ELF-MF exposure did not alter oxidative, antioxidative processes and lipid peroxidation in submandibular gland of rats. However, 100 µT and 500 µT ELF-MF exposure decreased CAT activity in parotid gland. J Clin Exp Invest 2014; 5 (2: 219-225

  1. Extremely Low-Frequency Magnetic Fields and Redox-Responsive Pathways Linked to Cancer Drug Resistance: Insights from Co-Exposure-Based In Vitro Studies

    Directory of Open Access Journals (Sweden)

    Stefano Falone

    2018-02-01

    Full Text Available Electrical devices currently used in clinical practice and common household equipments generate extremely low-frequency magnetic fields (ELF-MF that were classified by the International Agency for Research on Cancer as “possible carcinogenic.” Assuming that ELF-MF plays a role in the carcinogenic process without inducing direct genomic alterations, ELF-MF may be involved in the promotion or progression of cancers. In particular, ELF-MF-induced responses are suspected to activate redox-responsive intracellular signaling or detoxification scavenging systems. In fact, improved protection against oxidative stress and redox-active xenobiotics is thought to provide critical proliferative and survival advantage in tumors. On this basis, an ever-growing research activity worldwide is attempting to establish whether tumor cells may develop multidrug resistance through the activation of essential cytoprotective networks in the presence of ELF fields, and how this might trigger relevant changes in tumor phenotype. This review builds a framework around how the activity of redox-responsive mediators may be controlled by co-exposure to ELF-MF and reactive oxygen species-generating agents in tumor and cancer cells, in order to clarify whether and how such potential molecular targets could help to minimize or neutralize the functional interaction between ELF-MF and malignancies.

  2. Deficits in water maze performance and oxidative stress in the hippocampus and striatum induced by extremely low frequency magnetic field exposure.

    Directory of Open Access Journals (Sweden)

    Yonghua Cui

    Full Text Available The exposures to extremely low frequency magnetic field (ELF-MF in our environment have dramatically increased. Epidemiological studies suggest that there is a possible association between ELF-MF exposure and increased risks of cardiovascular disease, cancers and neurodegenerative disorders. Animal studies show that ELF-MF exposure may interfere with the activity of brain cells, generate behavioral and cognitive disturbances, and produce deficits in attention, perception and spatial learning. Although, many research efforts have been focused on the interaction between ELF-MF exposure and the central nervous system, the mechanism of interaction is still unknown. In this study, we examined the effects of ELF-MF exposure on learning in mice using two water maze tasks and on some parameters indicative of oxidative stress in the hippocampus and striatum. We found that ELF-MF exposure (1 mT, 50 Hz induced serious oxidative stress in the hippocampus and striatum and impaired hippocampal-dependent spatial learning and striatum-dependent habit learning. This study provides evidence for the association between the impairment of learning and the oxidative stress in hippocampus and striatum induced by ELF-MF exposure.

  3. A mathematical model of extremely low frequency ocean induced electromagnetic noise

    International Nuclear Information System (INIS)

    Dautta, Manik; Faruque, Rumana Binte; Islam, Rakibul

    2016-01-01

    Magnetic Anomaly Detection (MAD) system uses the principle that ferromagnetic objects disturb the magnetic lines of force of the earth. These lines of force are able to pass through both water and air in similar manners. A MAD system, usually mounted on an aerial vehicle, is thus often employed to confirm the detection and accomplish localization of large ferromagnetic objects submerged in a sea-water environment. However, the total magnetic signal encountered by a MAD system includes contributions from a myriad of low to Extremely Low Frequency (ELF) sources. The goal of the MAD system is to detect small anomaly signals in the midst of these low-frequency interfering signals. Both the Range of Detection (R_d) and the Probability of Detection (P_d) are limited by the ratio of anomaly signal strength to the interfering magnetic noise. In this paper, we report a generic mathematical model to estimate the signal-to-noise ratio or SNR. Since time-variant electro-magnetic signals are affected by conduction losses due to sea-water conductivity and the presence of air-water interface, we employ the general formulation of dipole induced electromagnetic field propagation in stratified media [1]. As a first step we employ a volumetric distribution of isolated elementary magnetic dipoles, each having its own dipole strength and orientation, to estimate the magnetic noise observed by a MAD system. Numerical results are presented for a few realizations out of an ensemble of possible realizations of elementary dipole source distributions.

  4. The change of electric potentials in the oral cavity after application of extremely low frequency pulsed magnetic field

    Directory of Open Access Journals (Sweden)

    Piotr Skomro

    2012-12-01

    Full Text Available Electric potentials occurring in the oral cavity deserve attention as they may cause various diseases and subjective feelings, which are very difficult to treat. The aim of this study was to evaluate the electric potentials within the oral cavity in patients with metal fillings and metal prosthetic restorations, after using a pulsed electromagnetic field. The study was carried out on 84 patients. The Viofor JPS Classic device was used in the treatment. It generates a pulsed electromagnetic field with low induction of the extremely low frequency (ELF range. Average values of electric potentials in the preliminary test were about the same in both groups; they were 148.8 mV and 145.5 mV. After another appliance of ELF fields there was found a steady decline in the average value of electric potentials in the study group. This decrease was statistically highly significant, while mean values of electric potentials in the control group were characterized by a slightly upward tendency. The obtained statistically significant reduction of electric potentials in the oral cavity of patients having metal fillings and metal prosthetic restorations, after application of the Viofor JPS Classic device, implies a huge impact of ELF pulsed electromagnetic field on inhibition of electrochemical processes, as well as on inhibition of dental alloy corrosion. 

  5. An investigation into the vector ellipticity of extremely low frequency magnetic fields from appliances in UK homes

    Science.gov (United States)

    Ainsbury, Elizabeth A.; Conein, Emma; Henshaw, Denis L.

    2005-07-01

    Elliptically polarized magnetic fields induce higher currents in the body compared with their plane polarized counterparts. This investigation examines the degree of vector ellipticity of extremely low frequency magnetic fields (ELF-MFs) in the home, with regard to the adverse health effects reportedly associated with ELF-MFs, for instance childhood leukaemia. Tri-axial measurements of the magnitude and phase of the 0-3000 Hz magnetic fields, produced by 226 domestic mains-fed appliances of 32 different types, were carried out in 16 homes in Worcestershire in the summer of 2004. Magnetic field strengths were low, with average (RMS) values of 0.03 ± 0.02 µT across all residences. In contrast, background field ellipticities were high, on average 47 ± 11%. Microwave and electric ovens produced the highest ellipticities: mean respective values of 21 ± 21% and 21 ± 17% were observed 20 cm away from these appliances. There was a negative correlation between field strength and field polarization, which we attribute to the higher relative field contribution close to each individual (single-phase) appliance. The measurements demonstrate that domestic magnetic fields are extremely complex and cannot simply be characterized by traditional measurements such as time-weighted average or peak exposure levels. We conclude that ellipticity should become a relevant metric for future epidemiological studies of health and ELF-MF exposure. This work is supported by the charity CHILDREN with LEUKAEMIA, registered charity number 298405.

  6. Quantum mechanical model for the anticarcinogenic effect of extremely-low-frequency electromagnetic fields on early chemical hepatocarcinogenesis

    Science.gov (United States)

    Godina-Nava, Juan José; Torres-Vega, Gabino; López-Riquelme, Germán Octavio; López-Sandoval, Eduardo; Samana, Arturo Rodolfo; García Velasco, Fermín; Hernández-Aguilar, Claudia; Domínguez-Pacheco, Arturo

    2017-02-01

    Using the conventional Haberkorn approach, it is evaluated the recombination of the radical pair (RP) singlet spin state to study theoretically the cytoprotective effect of an extremely-low-frequency electromagnetic field (ELF-EMF) on early stages of hepatic cancer chemically induced in rats. The proposal is that ELF-EMF modulates the interconversion rate of singlet and triplet spin states of the RP populations modifying the products from the metabolization of carcinogens. Previously, we found that the daily treatment with ELF-EMF 120 Hz inhibited the number and area of preneoplastic lesions in chemical carcinogenesis. The singlet spin population is evaluated diagonalizing the spin density matrix through the Lanczos method in a radical pair mechanism (RPM). Using four values of the interchange energy, we have studied the variations over the singlet population. The low magnetic field effect as a test of the influence over the enzymatic chemical reaction is evaluated calculating the quantum yield. Through a bootstrap technique the range is found for the singlet decay rate for the process. Applying the quantum measurements concept, we addressed the impact toward hepatic cells. The result contributes to improving our understanding of the chemical carcinogenesis process affected by charged particles that damage the DNA.

  7. An investigation into the vector ellipticity of extremely low frequency magnetic fields from appliances in UK homes

    International Nuclear Information System (INIS)

    Ainsbury, Elizabeth A; Conein, Emma; Henshaw, Denis L

    2005-01-01

    Elliptically polarized magnetic fields induce higher currents in the body compared with their plane polarized counterparts. This investigation examines the degree of vector ellipticity of extremely low frequency magnetic fields (ELF-MFs) in the home, with regard to the adverse health effects reportedly associated with ELF-MFs, for instance childhood leukaemia. Tri-axial measurements of the magnitude and phase of the 0-3000 Hz magnetic fields, produced by 226 domestic mains-fed appliances of 32 different types, were carried out in 16 homes in Worcestershire in the summer of 2004. Magnetic field strengths were low, with average (RMS) values of 0.03 ± 0.02 μT across all residences. In contrast, background field ellipticities were high, on average 47 ± 11%. Microwave and electric ovens produced the highest ellipticities: mean respective values of 21 ± 21% and 21 ± 17% were observed 20 cm away from these appliances. There was a negative correlation between field strength and field polarization, which we attribute to the higher relative field contribution close to each individual (single-phase) appliance. The measurements demonstrate that domestic magnetic fields are extremely complex and cannot simply be characterized by traditional measurements such as time-weighted average or peak exposure levels. We conclude that ellipticity should become a relevant metric for future epidemiological studies of health and ELF-MF exposure

  8. Co-Culture with Human Osteoblasts and Exposure to Extremely Low Frequency Pulsed Electromagnetic Fields Improve Osteogenic Differentiation of Human Adipose-Derived Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Sabrina Ehnert

    2018-03-01

    Full Text Available Human adipose-derived mesenchymal stem cells (Ad-MSCs have been proposed as suitable option for cell-based therapies to support bone regeneration. In the bone environment, Ad-MSCs will receive stimuli from resident cells that may favor their osteogenic differentiation. There is recent evidence that this process can be further improved by extremely low frequency pulsed electromagnetic fields (ELF-PEMFs. Thus, the project aimed at (i investigating whether co-culture conditions of human osteoblasts (OBs and Ad-MSCs have an impact on their proliferation and osteogenic differentiation; (ii whether this effect can be further improved by repetitive exposure to two specific ELF-PEMFs (16 and 26 Hz; (iii and the effect of these ELF-PEMFs on human osteoclasts (OCs. Osteogenic differentiation was improved by co-culturing OBs and Ad-MSCs when compared to the individual mono-cultures. An OB to Ad-MSC ratio of 3:1 had best effects on total protein content, alkaline phosphatase (AP activity, and matrix mineralization. Osteogenic differentiation was further improved by both ELF-PEMFs investigated. Interestingly, only repetitive exposure to 26 Hz ELF-PEMF increased Trap5B activity in OCs. Considering this result, a treatment with gradually increasing frequency might be of interest, as the lower frequency (16 Hz could enhance bone formation, while the higher frequency (26 Hz could enhance bone remodeling.

  9. Characterization of extremely low frequency magnetic fields from diesel, gasoline and hybrid cars under controlled conditions.

    Science.gov (United States)

    Hareuveny, Ronen; Sudan, Madhuri; Halgamuge, Malka N; Yaffe, Yoav; Tzabari, Yuval; Namir, Daniel; Kheifets, Leeka

    2015-01-30

    This study characterizes extremely low frequency (ELF) magnetic field (MF) levels in 10 car models. Extensive measurements were conducted in three diesel, four gasoline, and three hybrid cars, under similar controlled conditions and negligible background fields. Averaged over all four seats under various driving scenarios the fields were lowest in diesel cars (0.02 μT), higher for gasoline (0.04-0.05 μT) and highest in hybrids (0.06-0.09 μT), but all were in-line with daily exposures from other sources. Hybrid cars had the highest mean and 95th percentile MF levels, and an especially large percentage of measurements above 0.2 μT. These parameters were also higher for moving conditions compared to standing while idling or revving at 2500 RPM and higher still at 80 km/h compared to 40 km/h. Fields in non-hybrid cars were higher at the front seats, while in hybrid cars they were higher at the back seats, particularly the back right seat where 16%-69% of measurements were greater than 0.2 μT. As our results do not include low frequency fields (below 30 Hz) that might be generated by tire rotation, we suggest that net currents flowing through the cars' metallic chassis may be a possible source of MF. Larger surveys in standardized and well-described settings should be conducted with different types of vehicles and with spectral analysis of fields including lower frequencies due to magnetization of tires.

  10. Short-term effects of extremely low-frequency pulsed electromagnetic field and pulsed low-level laser therapy on rabbit model of corneal alkali burn.

    Science.gov (United States)

    Rezaei Kanavi, Mozhgan; Tabeie, Faraj; Sahebjam, Farzin; Poursani, Nima; Jahanbakhsh, Nazanin; Paymanpour, Pouya; AfsarAski, Sasha

    2016-04-01

    This study was conducted to investigate the effect of combining extremely low frequency-pulsed electromagnetic field (ELF-PEMF) and low-level laser therapy (LLLT) on alkali-burned rabbit corneas. Fifty alkali-burned corneas of 50 rabbits were categorized into five groups: ELF-PEMF therapy with 2 mT intensity (ELF 2) for 2 h daily; LLLT for 30 min twice daily; combined ELF-PEMF and LLLT (ELF + LLLT); medical therapy (MT); and control (i.e., no treatment). Clinical examination and digital photography of the corneas were performed on days 0, 2, 7, and 14. After euthanizing the rabbits, the affected eyes were evaluated by histopathology. The clinical and histopathologic results were compared between the groups. On days 7 and 14, no significant difference in the corneal defect area was evident between the ELF, LLLT, ELF + LLLT, and MT groups. Excluding the controls, none of the study groups demonstrated a significant corneal neovascularization in both routine histopathology and immunohistochemistry for CD31. Keratocyte loss was significantly higher in the MT group than in the ELF, LLLT, and ELF + LLLT groups. Moderate to severe stromal inflammation in the LLLT group was comparable with that in the MT group and was significantly lower than that in the other groups. In conclusion, combining LLLT and ELF was not superior to ELF alone or LLLT alone in healing corneal alkali burns. However, given the lower intensity of corneal inflammation and the lower rate of keratocytes loss with LLLT, this treatment may be superior to other proposed treatment modalities for healing alkali-burned corneas. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. A mathematical model of extremely low frequency ocean induced electromagnetic noise

    Energy Technology Data Exchange (ETDEWEB)

    Dautta, Manik, E-mail: manik.dautta@anyeshan.com; Faruque, Rumana Binte, E-mail: rumana.faruque@anyeshan.com; Islam, Rakibul, E-mail: rakibul.islam@anyeshan.com [Research & Development Engineer, Anyeshan Limited, Dhaka (Bangladesh)

    2016-07-12

    Magnetic Anomaly Detection (MAD) system uses the principle that ferromagnetic objects disturb the magnetic lines of force of the earth. These lines of force are able to pass through both water and air in similar manners. A MAD system, usually mounted on an aerial vehicle, is thus often employed to confirm the detection and accomplish localization of large ferromagnetic objects submerged in a sea-water environment. However, the total magnetic signal encountered by a MAD system includes contributions from a myriad of low to Extremely Low Frequency (ELF) sources. The goal of the MAD system is to detect small anomaly signals in the midst of these low-frequency interfering signals. Both the Range of Detection (R{sub d}) and the Probability of Detection (P{sub d}) are limited by the ratio of anomaly signal strength to the interfering magnetic noise. In this paper, we report a generic mathematical model to estimate the signal-to-noise ratio or SNR. Since time-variant electro-magnetic signals are affected by conduction losses due to sea-water conductivity and the presence of air-water interface, we employ the general formulation of dipole induced electromagnetic field propagation in stratified media [1]. As a first step we employ a volumetric distribution of isolated elementary magnetic dipoles, each having its own dipole strength and orientation, to estimate the magnetic noise observed by a MAD system. Numerical results are presented for a few realizations out of an ensemble of possible realizations of elementary dipole source distributions.

  12. Influence of extremely low frequency magnetic field on total protein and –SH groups concentrations in liver homogenates

    Directory of Open Access Journals (Sweden)

    Elżbieta Ciejka

    2014-10-01

    Full Text Available Background: Free radicals are atoms, molecules or their fragments, whose excess leads to the development of oxidative stress, the cause of many neoplastic, neurodegenerative and inflammatory diseases, as well as aging of organisms. Industrial pollution, tobacco smoke, ionizing radiation, ultrasound and magnetic fields are the major exogenous sources of free radicals. The low frequency magnetic field is commonly applied in physiotherapy. The aim of the present study was to evaluate the effect of extremely low frequency magnetic field (ELF-MF on the concentration of sulfhydryl groups (–SH and proteins in liver tissues of experimental animals depending on the time of exposure to the field. Material and Methods: Twenty one Sprague-Dawley male rats, aged 3–4 months were randomly divided into 3 experimental groups (each containing 7 animals: controls (group I, the rats exposed to ELF-MF of 40 Hz, 7 mT (this kind of the ELF-MF is mostly used in magnetotherapy, 30 min/day for 2 weeks (group II and the rats exposed to 40 Hz, 7 mT for 60 min/day for 2 weeks (group III. The concentrations of proteins and sulfhydryl groups in the liver tissues were determined after exposure to magnetic fields. Results: Exposure to low magnetic field: 40 Hz, 7 mT for 30 min/day and 60 min/day for 2 weeks caused a significant increase in the concentration of –SH groups and total protein levels in the liver tissues. Conclusions: The study results suggest that exposure to magnetic fields leads to the development of adaptive mechanisms to maintain the balance in the body oxidation-reduction and in the case of the studied parameters does not depend on the time of exposure. Med Pr 2014;65(5:639–644

  13. Extremely low frequency electromagnetic field in combination with β ...

    African Journals Online (AJOL)

    Fatemeh Sanie-Jahromi

    Extremely low frequency (<300 Hz) electromagnetic field (EMF) is shown to decrease ... Production and hosting by Elsevier B.V. This is an open access article under ..... mouse liver induced by morphine and protected by antioxidants.

  14. Effects of Extremely Low Frequency Electromagnetic Fields on Melanogenesis through p-ERK and p-SAPK/JNK Pathways in Human Melanocytes

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    Yu-Mi Kim

    2017-10-01

    Full Text Available This study evaluated frequency-dependent effects of extremely low frequency electromagnetic fields (ELF-EMFs on melanogenesis by melanocytes in vitro. Melanocytes were exposed to 2 mT EMFs at 30–75 Hz for 3 days before melanogenesis was examined. Exposure to ELF-EMFs at 50 and 60 Hz induced melanogenic maturation without cell damage, without changing cell proliferation and mitochondrial activity. Melanin content and tyrosinase activity of cells exposed to 50 Hz were higher than in controls, and mRNA expression of tyrosinase-related protein-2 was elevated relative to controls at 50 Hz. Phosphorylated cyclic adenosine monophosphate response element-binding protein (p-CREB levels were higher than controls in cells exposed to ELF-EMFs at 50–75 Hz. Immunohistochemical staining showed that melanocyte-specific markers (HMB45, Melan-A were strongly expressed in cells exposed to EMFs at 50 and 60 Hz compared to controls. Thus, exposure to ELF-EMFs at 50 Hz could stimulate melanogenesis in melanocytes, through activation of p-CREB and p-p38 and inhibition of phosphorylated extracellular signal-regulated protein kinase and phosphorylated stress-activated protein kinase/c-Jun N-terminal kinase. The results may form the basis of an appropriate anti-gray hair treatment or be applied in a therapeutic device for inducing repigmentation in the skin of vitiligo patients.

  15. Can safe and long-term exposure to extremely low frequency (50 Hz) magnetic fields affect apoptosis, reproduction, and oxidative stress?

    Science.gov (United States)

    Akdag, Mehmet Zulkuf; Dasdag, Suleyman; Uzunlar, Ali Kemal; Ulukaya, Engin; Oral, Arzu Yilmaztepe; Çelik, Necla; Akşen, Feyzan

    2013-12-01

    To determine whether 50 Hz extremely low frequency-magnetic fields (ELF-MF) affects apoptotic processes, oxidative damage, and reproductive characteristics such as sperm count and morphology in rat testes. Thirty male Sprague-Dawley rats were used in the present study, which were divided into three groups (sham group, n = 10, and two experimental groups, n = 10 for each group). Rats in the experimental group were exposed to 100 and 500 μT ELF-MF (2 h/day, 7 days/week, for 10 months) corresponding to exposure levels that are considered safe for humans. The same experimental procedures were applied to the sham group, but the ELF generator was turned off. Tissues from the testes were immunohistochemically stained for active (cleaved) caspase-3 in order to measure the apoptotic index by a semi-quantitative scoring system. The levels of catalase (CAT), malondialdehyde (MDA), myeloperoxidase (MPO), total antioxidative capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) were also measured. Additionally, epididymal sperm count and sperm morphology was evaluated. There were no significant differences in the reproductive and oxidative stress parameters between the sham group and the exposed groups (p > 0.05). While no difference was observed between the final apoptosis score of the sham and the 100 μT ELF-MF group (p > 0.05), the final apoptosis score was higher in the 500 μT ELF-MF exposure group than in the sham group (p reproductive components such as sperm count and morphology in testes tissue of rats. However, long-term exposure to 500 μT ELF-MF did affect active-caspase-3 activity, which is a well-known apoptotic indicator.

  16. Extremely low frequency electromagnetic fields stimulation modulates autoimmunity and immune responses: a possible immuno-modulatory therapeutic effect in neurodegenerative diseases

    Directory of Open Access Journals (Sweden)

    Fabio Guerriero

    2016-01-01

    Full Text Available Increasing evidence shows that extremely low frequency electromagnetic fields (ELF-EMFs stimulation is able to exert a certain action on autoimmunity and immune cells. In the past, the efficacy of pulsed ELF-EMFs in alleviating the symptoms and the progression of multiple sclerosis has been supported through their action on neurotransmission and on the autoimmune mechanisms responsible for demyelination. Regarding the immune system, ELF-EMF exposure contributes to a general activation of macrophages, resulting in changes of autoimmunity and several immunological reactions, such as increased reactive oxygen species-formation, enhanced phagocytic activity and increased production of chemokines. Transcranial electromagnetic brain stimulation is a non-invasive novel technique used recently to treat different neurodegenerative disorders, in particular Alzheimer's disease. Despite its proven value, the mechanisms through which EMF brain-stimulation exerts its beneficial action on neuronal function remains unclear. Recent studies have shown that its beneficial effects may be due to a neuroprotective effect on oxidative cell damage. On the basis of in vitro and clinical studies on brain activity, modulation by ELF-EMFs could possibly counteract the aberrant pro-inflammatory responses present in neurodegenerative disorders reducing their severity and their onset. The objective of this review is to provide a systematic overview of the published literature on EMFs and outline the most promising effects of ELF-EMFs in developing treatments of neurodegenerative disorders. In this regard, we review data supporting the role of ELF-EMF in generating immune-modulatory responses, neuromodulation, and potential neuroprotective benefits. Nonetheless, we reckon that the underlying mechanisms of interaction between EMF and the immune system are still to be completely understood and need further studies at a molecular level.

  17. Effects of short term and long term Extremely Low Frequency Magnetic Field on depressive disorder in mice: Involvement of nitric oxide pathway.

    Science.gov (United States)

    Madjid Ansari, Alireza; Farzampour, Shahrokh; Sadr, Ali; Shekarchi, Babak; Majidzadeh-A, Keivan

    2016-02-01

    Previous reports on the possible effects of Extremely Low Frequency Magnetic Fields (ELF MF) on mood have been paradoxical in different settings while no study has yet been conducted on animal behavior. In addition, it was shown that ELF MF exposure makes an increase in brain nitric oxide level. Therefore, in the current study, we aimed to assess the possible effect(s) of ELF MF exposure on mice Forced Swimming Test (FST) and evaluate the probable role of the increased level of nitric oxide in the observed behavior. Male adult mice NMRI were recruited to investigate the short term and long term ELF MF exposure (0.5 mT and 50 Hz, single 2h and 2 weeks 2h a day). Locomotor behavior was assessed by using open-field test (OFT) followed by FST to evaluate the immobility time. Accordingly, NΩ-nitro-l-arginine methyl ester 30 mg/kg was used to exert anti-depressant like effect. According to the results, short term exposure did not alter the immobility time, whereas long term exposure significantly reduces immobility time (pmice, whereas short term exposure has no significant effect. Also, reversing the anti-depressant activity of L-NAME indicates a probable increase in the brain nitric oxide. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Assessment of occupational risks to extremely low frequency magnetic fields: Validation of an empirical non-expert approach

    Directory of Open Access Journals (Sweden)

    Mariam El-Zein

    2016-12-01

    Full Text Available The expert method of exposure assignment involves relying on chemists or hygienists to estimate occupational exposures using information collected on study subjects. Once the estimation method for a particular contaminant has been made available in the literature, it is not known whether a non-expert, briefly trained by an expert remaining available to answer ad hoc questions, can provide reliable exposure estimates. We explored this issue by comparing estimates of exposure to extremely low frequency magnetic fields (ELF-MF obtained by an expert to those from a non-expert. Using a published exposure matrix, both the expert and non-expert independently calculated a weekly time-weighted average exposure for 208 maternal jobs by considering three main determinants: the work environment, magnetic field sources, and duration of use or exposure to given sources. Agreement between assessors was tested using the Bland-Altman 95% limits of agreement. The overall mean difference in estimates between the expert and non-expert was 0.004 μT (standard deviation 0.104. The 95% limits of agreement were −0.20 μT and +0.21 μT. The work environments and exposure sources were almost always similarly identified but there were differences in estimating exposure duration. This occurred mainly when information collected from study subjects was not sufficiently detailed. Our results suggest that following a short training period and the availability of a clearly described method for estimating exposures, a non-expert can cost-efficiently and reliably assign exposure, at least to ELF-MF.

  19. Investigation of Resonance Effect Caused by Local Exposure of Extremely Low Frequency Magnetic Field on Brain Signals: A Randomize Clinical Trial

    Directory of Open Access Journals (Sweden)

    Rasul Zadeh Tabataba’ei K

    2011-03-01

    Full Text Available Background and Objectives: Some studies have investigated the effects of extremely low frequency magnetic fields (ELF-MFs on brain signals, but only few of them have reported that humans exposed to magnetic fields exhibit changes in brain signals at the frequency of stimulation, i.e. resonance effect. In most investigations, researchers usually take advantage of a uniform field which encompasses the head. The aim of present study was to expose different parts of the brain to ELF-MFs locally and to investigate variation of brain signal and resonance effect.Methods: The subjects consisting of 19 male-students with the mean age of 25.6±1.6 years participated in this study. Local ELF-MFs with 3, 5, 10, 17 and 45Hz frequencies and 240 μT intensity was applied on five points (T3, T4, Cz, F3 and F4 of participants scalp Separately in 10-20 system. In the end, relative power over this points in common frequency bands and at the frequency of magnetic fields was evaluated by paired t-test.Results: Exposure of Central area by local magnetic field caused significant change (p<0.05 in the forehead alpha band. Reduction in the alpha band over central area was observed when temporal area was exposed to ELF MF.Conclusion: The results showed that resonance effect in the brain signals caused by local magnetic field exposure was not observed and change in every part of the relative power spectrum might occur. The changes in the EEG bands were not limited necessarily to the exposure point.

  20. Occupational exposure to electromagnetic fields (Emf) of extremely low frequency and Alzheimer disease

    International Nuclear Information System (INIS)

    Mir, L.

    2008-01-01

    Occupational exposure to extremely low frequency electromagnetic fields (between 3 and 3000 hz) is one potential risk factor for Alzheimer disease. this critical meta-analysis of the published epidemiologic work suggests the existence of an association in a very heterogeneous dataset. It looks for potential sources of error, examines the areas of uncertainty, and calls for the pursuit of further research. (author)

  1. Domain Decomposition for Computing Extremely Low Frequency Induced Current in the Human Body

    OpenAIRE

    Perrussel , Ronan; Voyer , Damien; Nicolas , Laurent; Scorretti , Riccardo; Burais , Noël

    2011-01-01

    International audience; Computation of electromagnetic fields in high resolution computational phantoms requires solving large linear systems. We present an application of Schwarz preconditioners with Krylov subspace methods for computing extremely low frequency induced fields in a phantom issued from the Visible Human.

  2. No effects of power line frequency extremely low frequency electromagnetic field exposure on selected neurobehavior tests of workers inspecting transformers and distribution line stations versus controls.

    Science.gov (United States)

    Li, Li; Xiong, De-fu; Liu, Jia-wen; Li, Zi-xin; Zeng, Guang-cheng; Li, Hua-liang

    2014-03-01

    We aimed to evaluate the interference of 50 Hz extremely low frequency electromagnetic field (ELF-EMF) occupational exposure on the neurobehavior tests of workers performing tour-inspection close to transformers and distribution power lines. Occupational short-term "spot" measurements were carried out. 310 inspection workers and 300 logistics staff were selected as exposure and control. The neurobehavior tests were performed through computer-based neurobehavior evaluation system, including mental arithmetic, curve coincide, simple visual reaction time, visual retention, auditory digit span and pursuit aiming. In 500 kV areas electric field intensity at 71.98% of total measured 590 spots were above 5 kV/m (national occupational standard), while in 220 kV areas electric field intensity at 15.69% of total 701 spots were above 5 kV/m. Magnetic field flux density at all the spots was below 1,000 μT (ICNIRP occupational standard). The neurobehavior score changes showed no statistical significance. Results of neurobehavior tests among different age, seniority groups showed no significant changes. Neurobehavior changes caused by daily repeated ELF-EMF exposure were not observed in the current study.

  3. Exposure to extremely low frequency (50 Hz electromagnetic field changes the survival rate and morphometric characteristics of neurosecretory neurons of the earthworm Eisenia foetida (Oligochaeta under illumination stress

    Directory of Open Access Journals (Sweden)

    Banovački Zorana

    2013-01-01

    Full Text Available An in vivo model was set up to establish the behavioral stress response (rate of survival and morphometric characteristics of A1 protocerebral neurosecretory neurons (cell size of Eisenia foetida (Oligochaeta as a result of the synergetic effect of extremely low frequency electromagnetic fields (ELF-EMF - 50 Hz, 50 μT, 17 V/m and 50 Hz, 150 μT, 17 V/m, respectively and constant illumination (420-450 lux. If combined, these two stressors significantly (p<0.05 increased the survival rate of E. foetida in the 150 μT-exposed animals, because of delayed caudal autotomy reflex, an indicator of stress response. In addition, morphometric analysis indicated that there were changes in the protocerebral neurosecretory cells after exposure to the ELF-EMF. The present data support the view that short-term ELF-EMF exposure in “windows” of intensity is likely to stimulate the immune and neuroendocrine response of E. foetida.

  4. [Effects of extremely low frequency electromagnetic radiation on cardiovascular system of workers].

    Science.gov (United States)

    Zhao, Long-yu; Song, Chun-xiao; Yu, Duo; Liu, Xiao-liang; Guo, Jian-qiu; Wang, Chuan; Ding, Yuan-wei; Zhou, Hong-xia; Ma, Shu-mei; Liu, Xiao-dong; Liu, Xin

    2012-03-01

    To observe the exposure levels of extremely low frequency electromagnetic fields in workplaces and to analyze the effects of extremely low frequency electromagnetic radiation on cardiovascular system of occupationally exposed people. Intensity of electromagnetic fields in two workplaces (control and exposure groups) was detected with EFA-300 frequency electromagnetic field strength tester, and intensity of the noise was detected with AWA5610D integral sound level. The information of health physical indicators of 188 controls and 642 occupationally exposed workers was collected. Data were analyzed by SPSS17.0 statistic software. The intensity of electric fields and the magnetic fields in exposure groups was significantly higher than that in control group (P 0.05). The results of physical examination showed that the abnormal rates of HCY, ALT, AST, GGT, ECG in the exposure group were significantly higher than those in control group (P 0.05). Exposure to extremely low frequency electromagnetic radiation may have some effects on the cardiovascular system of workers.

  5. Efficacy and safety evaluation of systemic extremely low frequency magnetic fields used in the healing of diabetic foot ulcers--phase II data.

    Science.gov (United States)

    Cañedo-Dorantes, Luis; Soenksen, Luis R; García-Sánchez, Clara; Trejo-Núñez, Daphny; Pérez-Chávez, Fernando; Guerrero, Arturo; Cardona-Vicario, Melisa; García-Lara, Carlos; Collí-Magaña, Dianelly; Serrano-Luna, Gregorio; Angeles Chimal, José S; Cabrera, Guillermo

    2015-08-01

    Cellular and animal models investigating extremely low frequency magnetic fields (ELF-MF) have reported promotion of leukocyte-endothelial interactions, angiogenesis, myofibroblast and keratinocyte proliferation, improvement of peripheral neuropathy and diabetic wound healing. In humans, it has also been reported that systemic exposure to ELF-MF stimulates peripheral blood mononuclear cells, promoting angiogenesis and healing of chronic leg ulcers. The aim of the study was to investigate the effect of exposing different blood volumes to specific ELF-MFs (120 Hz sinusoidal waves of 0.4-0.9 mT RMS) to induce healing of diabetic foot ulcers (DFUs). Twenty six diabetic patients with non-responsive DFUs were divided into two exposure groups to receive treatment and record healing time. The forearm group, exposed to ELF-MF 2 h/day, twice weekly (3.6 l of blood/session); and the thorax group, exposed 25 min/day, 2 times/week (162.5 l of blood/session). Treatment period was 100 days or upon complete healing. Ulcer recurrences and adverse effects were investigated during short-term (<1 year) and long-term (3.4-7.8 years) follow-up. Mean healing time was 61.48 ± 33.08 days in the forearm group and 62.56 ± 29.33 days for the thorax group. No adverse effects or ulcer recurrences in the original ulcer site were reported during treatment, the short-term follow-up period or the long-term follow-up period in both groups. Healing time was independent of the amount of blood exposed to ELF-MF used in this trial. ELF-MFs are effective and safe and could be applied to non-healing DFUs in conjunction with other preventive interventions to reduce DFUs complications. Copyright © 2015 IMSS. Published by Elsevier Inc. All rights reserved.

  6. Extremely Low Frequency (ELF) Communications System Bio-Effects Library Development.

    Science.gov (United States)

    1985-10-01

    44 0 I" " I II - I-I -~i it I it LI S oit ’II La S LLa ..5 I it° it L I itS CD L C La .L- 4.-,, .-.5 c i I- i F6 ’n 1-5 ., , -j -! i h- m. it C...aII a - ma U, a"I o aao a - co 9111 aa "L . ’ * Ia a- I’ c a - ,n a , • lit a w a i a l: * -I a". a aa nC-aa a i Li a IM * a;a -a O~~c acca aZ 31 a a a

  7. Extremely Low Frequency (ELF) Vertical Electric Field Exposure of Rats: Irradiation Facility

    Science.gov (United States)

    1977-05-01

    altered inside an animal cage even with wet or dry litter and full food and water containers. Rats weighing approximately 300 g in adjacent cages caused...with guard circuit Field inside empty cage Field inside complete cage ( litter (wet or dry) + food + water) Field variations caused by 300 g rat...blanket 250 Iron 60 Broiler 130 Hair dryer 40 Vaporizer 40 Refrigerator 60 Color TV 30 Stereo 90 Coffee pot 30 Vacuum cleaner 16 Clock radio

  8. [Influence of extremely low frequency magnetic field on total protein and -sh groups concentrations in liver homogenates].

    Science.gov (United States)

    Ciejka, Elżbieta; Kowalczyk, Agata; Gorąca, Anna

    2014-01-01

    Free radicals are atoms, molecules or their fragments, whose excess leads to the development of oxidative stress, the cause of many neoplastic, neurodegenerative and inflammatory diseases, as well as aging of organisms. Industrial pollution, tobacco smoke, ionizing radiation, ultrasound and magnetic fields are the major exogenous sources of free radicals. The low frequency mag- netic field is commonly applied in physiotherapy. The aim of the present study was to evaluate the effect of extremely low frequency magnetic field (1L.F-MF) on the concentration ofsullhydryl groups (-SH) and proteins in liver tissues of experimental animals de- pending on the time of exposure to the field. Twenty one Sprague-D)awley male rats, aged 3-4 months were randomly divided into 3 experimental groups (each containing 7 animals): controls (group I), the rats exposed to IEI.F-MF of 40 Hz, 7 mT (this kind of the ELF-MF is mostly used in magnetotherapy), 30 min/day for 2 weeks (group II) and the rats exposed to 40 Hz, 7 mT for 60 min/day for 2 weeks (group III). The concentrations of proteins and sulfhydryl groups in the liver tissues were determined after exposure to magnetic fields. Exposure to low magnetic field: 40 Hz, 7 mT for 30 min/day and 60 min/day for 2 weeks caused a significant increase in the concentration of-SH groups and total protein levels in the liver tissues. The study results suggest that exposure to magnetic fields leads to the development of adaptive mechanisms to maintain the balance in the body oxidation-reduction and in the case of the studied parameters does not depend on the time of exposure.

  9. Induction of chromosomal aberrations in human primary fibroblasts and immortalized cancer cells exposed to extremely-low-frequency electromagnetic fields

    International Nuclear Information System (INIS)

    Seyyedi, S. S.; Mozdarani, H.; Rezaei Tavirani, M.; Heydari, S.

    2010-01-01

    Rapidly increasing possibilities of exposure to environmental extremely low-frequency electromagnetic fields have become a topic of worldwide investigation. Epidemiological and laboratory studies suggest that exposure to extremely low-frequency electromagnetic fields may increase cancer risk therefore assessment of chromosomal damage in various cell lines might be of predictive value for future risk estimation. Materials and Methods: Primary cultures of fibroblasts from human skin biopsy were exposed to continuous extremely low-frequency electromagnetic fields (3, 50 and 60 Hz, sinusoidal, 3h, and 4 m T). Also immortalized cell lines, SW480, MCF-7 and 1321N1 were exposed to continuous extremely low-frequency electromagnetic fields (50 Hz, sinusoidal, 3 h, 4 m T). Metaphase plates Were prepared according to standard methods and stained in 5% Giemsa solution. Chromosomal aberrations of both chromosome and chromatid types were scored to evaluate the effects of extremely low-frequency electromagnetic fields on primary or established cell lines. Results: Results indicate that by increasing the frequency of extremely low-frequency electromagnetic fields, chromosomal aberrations were increased up to 7-fold above background levels in primary human fibroblast cells. In addition, continuous exposure to a 50 Hz electromagnetic field led to a significant increase in chromosomal aberrations in SW480, MCF-7 and 1321N1 cell lines compared to sham control. Conclusion: Results obtained indicate that extremely low-frequency electromagnetic fields has the potential for induction of chromosomal aberrations in all cell types.

  10. Determination of the effects of extremely low frequency electromagnetic fields on the percentages of peripheral blood leukocytes and histology of lymphoid organs of the mouse

    International Nuclear Information System (INIS)

    Cicekcibasi, Aynur E.; Salbacak, A.; Buyukmumcu, M.; Okudan, N.; Celik, I.; Ozkan, Y.

    2008-01-01

    Objective was to determine the effects of very weak, extremely low frequency (50Hz) electromagnetic field (ELF-EMF) on the relative spleen weight, lymphoid organ histology, peripheral blood leukocyte and alpha-naphthyl acetate esterase positive (ANAE-positive) lymphocyte percentages of mouse. The study was carried out in the Scientific Research and Application Center of Selcuk University, Konya, Turkey in 2005. A total of 120 Swiss albino mice were divided into 6 groups (20 in each group). The experimental animals were exposed to 1, 2, 3, 4 and 5 uT flux intensities (rms) of EMF at 50 Hz for 40 days. In the exposure groups with 20 animals, the body weight (BW) increased gradually in higher field intensities and reached at peak level in the 4 uT and then slightly decreased. The relative spleen weight (% of BW) was not affected. The ELF-EMF treatment did not cause any significant change in lymphocyte, monocyte and ANA-positive lymphocyte ratios, whereas percentages of neutropholis and basophiles changed non-linearly. Any change in the lymphoid organ histology which attributable to the field effect, was not observed in the exposure groups. Extremely frequency-EMF exposure with the flux intensities between 1-5 uT for 40 days did not cause any effect on the relative spleen weight, lymphoid organ histology, leukocyte and ANAE-positive lymphocyte percentages of the mouse. (author)

  11. Analysis of the Extremely Low Frequency Magnetic Field Emission from Laptop Computers

    Directory of Open Access Journals (Sweden)

    Brodić Darko

    2016-03-01

    Full Text Available This study addresses the problem of magnetic field emission produced by the laptop computers. Although, the magnetic field is spread over the entire frequency spectrum, the most dangerous part of it to the laptop users is the frequency range from 50 to 500 Hz, commonly called the extremely low frequency magnetic field. In this frequency region the magnetic field is characterized by high peak values. To examine the influence of laptop’s magnetic field emission in the office, a specific experiment is proposed. It includes the measurement of the magnetic field at six laptop’s positions, which are in close contact to its user. The results obtained from ten different laptop computers show the extremely high emission at some positions, which are dependent on the power dissipation or bad ergonomics. Eventually, the experiment extracts these dangerous positions of magnetic field emission and suggests possible solutions.

  12. Assessment of multiple frequency ELF electric and magnetic field exposure

    International Nuclear Information System (INIS)

    Leitgeb, N

    2008-01-01

    Electromagnetic fields both in daily life and at workplaces exhibit increasingly complex frequency spectra. Present spectral assessment rules proved to be too conservative for health risk assessment. This is because they are based on the assumption that cells would react like linear systems in terms of responding to a sum of frequencies by a sum of independent responses to each individual frequency. Based on numerical investigations with the Hodgkin-Huxley and the Frankenhaeuser-Huxley nerve cell models, it could be shown that accounting for the nonlinear behaviour of cellular excitation processes avoids considerable overestimation of simultaneous exposures to multiple frequency ELF electric and magnetic fields. Besides this, it could be shown that the role of phase relationships is less important than that assumed so far. The present assessment rules lead to non-compliances of marketed electric appliances. For general application, a nonlinear biology-based assessment (NBBA) rule has been proposed, validated and proven advantageous compared with ICNIRP's rule. While staying conservative it avoids unnecessary overestimation and demonstrates compliance even in cases of suspected non-conformities. It is up to responsible bodies to decide upon the adoption of this proposal and the potential need for implementing additional or reducing the already incorporated safety factors

  13. Response identification in the extremely low frequency region of an electret condenser microphone.

    Science.gov (United States)

    Jeng, Yih-Nen; Yang, Tzung-Ming; Lee, Shang-Yin

    2011-01-01

    This study shows that a small electret condenser microphone connected to a notebook or a personal computer (PC) has a prominent response in the extremely low frequency region in a specific environment. It confines most acoustic waves within a tiny air cell as follows. The air cell is constructed by drilling a small hole in a digital versatile disk (DVD) plate. A small speaker and an electret condenser microphone are attached to the two sides of the hole. Thus, the acoustic energy emitted by the speaker and reaching the microphone is strong enough to actuate the diaphragm of the latter. The experiments showed that, once small air leakages are allowed on the margin of the speaker, the microphone captured the signal in the range of 0.5 to 20 Hz. Moreover, by removing the plastic cover of the microphone and attaching the microphone head to the vibration surface, the low frequency signal can be effectively captured too. Two examples are included to show the convenience of applying the microphone to pick up the low frequency vibration information of practical systems.

  14. Response Identification in the Extremely Low Frequency Region of an Electret Condenser Microphone

    Directory of Open Access Journals (Sweden)

    Shang-Yin Lee

    2011-01-01

    Full Text Available This study shows that a small electret condenser microphone connected to a notebook or a personal computer (PC has a prominent response in the extremely low frequency region in a specific environment. It confines most acoustic waves within a tiny air cell as follows. The air cell is constructed by drilling a small hole in a digital versatile disk (DVD plate. A small speaker and an electret condenser microphone are attached to the two sides of the hole. Thus, the acoustic energy emitted by the speaker and reaching the microphone is strong enough to actuate the diaphragm of the latter. The experiments showed that, once small air leakages are allowed on the margin of the speaker, the microphone captured the signal in the range of 0.5 to 20 Hz. Moreover, by removing the plastic cover of the microphone and attaching the microphone head to the vibration surface, the low frequency signal can be effectively captured too. Two examples are included to show the convenience of applying the microphone to pick up the low frequency vibration information of practical systems.

  15. A pilot investigation of the effect of extremely low frequency pulsed electromagnetic fields on humans' heart rate variability.

    Science.gov (United States)

    Baldi, Emilio; Baldi, Claudio; Lithgow, Brian J

    2007-01-01

    The question whether pulsed electromagnetic field (PEMF) can affect the heart rhythm is still controversial. This study investigates the effects on the cardiocirculatory system of ELF-PEMFs. It is a follow-up to an investigation made of the possible therapeutic effect ELF-PEMFs, using a commercially available magneto therapeutic unit, had on soft tissue injury repair in humans. Modulation of heart rate (HR) or heart rate variability (HRV) can be detected from changes in periodicity of the R-R interval and/or from changes in the numbers of heart-beat/min (bpm), however, R-R interval analysis gives only a quantitative insight into HRV. A qualitative understanding of HRV can be obtained considering the power spectral density (PSD) of the R-R intervals Fourier transform. In this study PSD is the investigative tool used, more specifically the low frequency (LF) PSD and high frequency (HF) PSD ratio (LF/HF) which is an indicator of sympatho-vagal balance. To obtain the PSD value, variations of the R-R time intervals were evaluated from a continuously recorded ECG. The results show a HR variation in all the subjects when they are exposed to the same ELF-PEMF. This variation can be detected by observing the change in the sympatho-vagal equilibrium, which is an indicator of modulation of heart activity. Variation of the LF/HF PSD ratio mainly occurs at transition times from exposure to nonexposure, or vice versa. Also of interest are the results obtained during the exposure of one subject to a range of different ELF-PEMFs. This pilot study suggests that a full investigation into the effect of ELF-PEMFs on the cardiovascular system is justified.

  16. Treatment of patients with vulgar psoriasis through electromagnetic field of extremely low frequency

    International Nuclear Information System (INIS)

    Batista Romagosa, Maritza; Soriano Gonzalez, Blanca Ines; Bergues Cabrales, Luis Enrique

    2012-01-01

    A controlled and randomized clinical therapeutical assay in phase III was carried out in 52 patients with vulgar psoriasis, who were assisted in the Dermatology department of 'Dr Joaquin Castillo Duany' Clinical Surgical Hospital in Santiago de Cuba, from 2005 to 2010 who were divided into 2 groups (26 members each): the active group which was conventionally treated with 20% cade ointment; and the experimental group, to which the extremely low frequency electromagnetic field was applied, with the objective of determining the effectiveness of this field in those affected during the periods of crisis and intercrisis. The studied population was clinically characterized by means of a frequency analysis, while the hypothesis tests were used for the evaluation of proportions which null hypothesis were accepted with 5 % as maximum error. In the series the used field was effective to treat the disorder during crisis and more effective than the cade ointment to prolong the intercrisis stage, without causing adverse reactions, so that it constituted a new alternative therapy that can be generalized in the dermatological services of the country, in order to improve the life quality of those who suffer that dermatosis

  17. Molecular gyroscopes and biological effects of weak extremely low-frequency magnetic fields

    International Nuclear Information System (INIS)

    Binhi, V.N.; Savin, A.V.

    2002-01-01

    Extremely low-frequency magnetic fields are known to affect biological systems. In many cases, biological effects display 'windows' in biologically effective parameters of the magnetic fields: most dramatic is the fact that the relatively intense magnetic fields sometimes do not cause appreciable effect, while smaller fields of the order of 10-100 μT do. Linear resonant physical processes do not explain the frequency windows in this case. Amplitude window phenomena suggest a nonlinear physical mechanism. Such a nonlinear mechanism has been proposed recently to explain those 'windows'. It considers the quantum-interference effects on the protein-bound substrate ions. Magnetic fields cause an interference of ion quantum states and change the probability of ion-protein dissociation. This ion-interference mechanism predicts specific magnetic-field frequency and amplitude windows within which the biological effects occur. It agrees with a lot of experiments. However, according to the mechanism, the lifetime Γ -1 of ion quantum states within a protein cavity should be of unrealistic value, more than 0.01 s for frequency band 10-100 Hz. In this paper, a biophysical mechanism has been proposed, which (i) retains the attractive features of the ion interference mechanism, i.e., predicts physical characteristics that might be experimentally examined and (ii) uses the principles of gyroscopic motion and removes the necessity to postulate large lifetimes. The mechanism considers the dynamics of the density matrix of the molecular groups, which are attached to the walls of protein cavities by two covalent bonds, i.e., molecular gyroscopes. Numerical computations have shown almost free rotations of the molecular gyroscopes. The relaxation time due to van der Waals forces was about 0.01 s for the cavity size of 28 Aa

  18. The effects of extreme low frequency pulsed electromagnetic field on bone mineral density and incidence of fractures in patients with end - stage renal disease on dialysis - three year follow up study

    Directory of Open Access Journals (Sweden)

    Rakočević-Hrnjak Aleksandra

    2018-01-01

    Full Text Available Background/Aim. A variety of physical therapy options has been developed for the treatment of musculoskeletal disorders including those characterized with low bone mineral density (BMD. Extreme low frequency pulsed electromagnetic field (ELF-PEMF can accelerate bone formation. Patients with end stage of renal disease (ESRD are predisposed to high incidence of fractures due to bone disorder with multifactorial pathogenesis. Vitamin D, calcium supplements, antiresorptive and anabolic drugs in those patients have changed pharmacodynamics and pharmacokinetics and have minimal or limited effects. The aim of this study was to assess the effectiveness of long-term ELF-PEMF therapy applied in concordance with physical exercise on bone mass, incidence of new bone fractures and parathyroid hormone concentrations in ESRD patients on dialysis. Methods. In this 3-year prospective clinical trial, 151 patients with ESRD on dialysis program were subjected to treatment with ELF-PEMF (18 Hz, 2 mT applied during 40 min after 10 consecutive dialysis procedures, 4 times through one year (120 treatments in total during three years together with kinesitherapy (study group or only with kinesitherapy (control group on the voluntary basis. Results. Total of 124 patients have completed the study. In the study group (n = 54, regardless of sex, significant improvements of BMD, T-score and Z-score on both lumbar spine and femoral neck were achieved after 3-year treatment with ELF-PEMF. In the control group (n = 70, significant decreases of BMD, T-score and Z-score as well as the higher incidence of new bone fractures were recorded. Conclusion. ELF-PEMF could be a convenient and safe non-pharmacological therapeutic strategy for fracture prevention in nephrology practices.

  19. Cellular processes involved in human epidermal cells exposed to extremely low frequency electric fields.

    Science.gov (United States)

    Collard, J-F; Hinsenkamp, M

    2015-05-01

    characterized by an accelerated regulation after extremely low frequency pulsed stimulation also confirms their role in the processes of cell proliferation and differentiation. Bioinformatics approach allows in-depth research, without the bias of pre-selection, on cellular processes involved in a huge gene list. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Investigation of the radiation properties of magnetospheric ELF waves induced by modulated ionospheric heating

    Science.gov (United States)

    Wang, Feng; Ni, Binbin; Zhao, Zhengyu; Zhao, Shufan; Zhao, Guangxin; Wang, Min

    2017-05-01

    Electromagnetic extremely low frequency (ELF) waves play an important role in modulating the Earth's radiation belt electron dynamics. High-frequency (HF) modulated heating of the ionosphere acts as a viable means to generate artificial ELF waves. The artificial ELF waves can reside in two different plasma regions in geo-space by propagating in the ionosphere and penetrating into the magnetosphere. As a consequence, the entire trajectory of ELF wave propagation should be considered to carefully analyze the wave radiation properties resulting from modulated ionospheric heating. We adopt a model of full wave solution to evaluate the Poynting vector of the ELF radiation field in the ionosphere, which can reflect the propagation characteristics of the radiated ELF waves along the background magnetic field and provide the initial condition of waves for ray tracing in the magnetosphere. The results indicate that the induced ELF wave energy forms a collimated beam and the center of the ELF radiation shifts obviously with respect to the ambient magnetic field with the radiation power inversely proportional to the wave frequency. The intensity of ELF wave radiation also shows a weak correlation with the size of the radiation source or its geographical location. Furthermore, the combination of ELF propagation in the ionosphere and magnetosphere is proposed on basis of the characteristics of the ELF radiation field from the upper ionospheric boundary and ray tracing simulations are implemented to reasonably calculate magnetospheric ray paths of ELF waves induced by modulated ionospheric heating.

  1. Biophysical control of the growth of Agrobacterium tumefaciens using extremely low frequency electromagnetic waves at resonance frequency.

    Science.gov (United States)

    Fadel, M Ali; El-Gebaly, Reem H; Mohamed, Shaimaa A; Abdelbacki, Ashraf M M

    2017-12-09

    Isolated Agrobacterium tumefaciens was exposed to different extremely low frequencies of square amplitude modulated waves (QAMW) from two generators to determine the resonance frequency that causes growth inhibition. The carrier was 10 MHz sine wave with amplitude ±10 Vpp which was modulated by a second wave generator with a modulation depth of ± 2Vpp and constant field strength of 200 V/m at 28 °C. The exposure of A. tumefaciens to 1.0 Hz QAMW for 90 min inhibited the bacterial growth by 49.2%. In addition, the tested antibiotics became more effective against A. tumefaciens after the exposure. Furthermore, results of DNA, dielectric relaxation and TEM showed highly significant molecular and morphological changes due to the exposure to 1.0 Hz QAMW for 90 min. An in-vivo study has been carried out on healthy tomato plants to test the pathogenicity of A. tumefaciens before and after the exposure to QAMW at the inhibiting frequency. Symptoms of crown gall and all pathological symptoms were more aggressive in tomato plants treated with non-exposed bacteria, comparing with those treated with exposed bacteria. We concluded that, the exposure of A. tumefaciens to 1.0 Hz QAMW for 90 min modified its cellular activity and DNA structure, which inhibited the growth and affected the microbe pathogenicity. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Investigation of monolithic passively mode-locked quantum dot lasers with extremely low repetition frequency.

    Science.gov (United States)

    Xu, Tianhong; Cao, Juncheng; Montrosset, Ivo

    2015-01-01

    The dynamical regimes and performance optimization of quantum dot monolithic passively mode-locked lasers with extremely low repetition rate are investigated using the numerical method. A modified multisection delayed differential equation model is proposed to accomplish simulations of both two-section and three-section passively mode-locked lasers with long cavity. According to the numerical simulations, it is shown that fundamental and harmonic mode-locking regimes can be multistable over a wide current range. These dynamic regimes are studied, and the reasons for their existence are explained. In addition, we demonstrate that fundamental pulses with higher peak power can be achieved when the laser is designed to work in a region with smaller differential gain.

  3. Correlation analysis of extremely low-frequency variations of the natural electromagnetic Earth field and the problem of detecting periodical gravitational radiation

    International Nuclear Information System (INIS)

    Balakin, A.B.; Murzakhanov, Z.G.; Grunskaya, L.V.

    1994-01-01

    A proposal on the experimental detection of extremely low-frequency variations of the electromagnetic Earth field at the gravitational-wave frequency and method for correlation processing results of the experiments are described. 14 refs

  4. Stimulation of neural differentiation in human bone marrow mesenchymal stem cells by extremely low-frequency electromagnetic fields incorporated with MNPs.

    Science.gov (United States)

    Choi, Yun-Kyong; Lee, Dong Heon; Seo, Young-Kwon; Jung, Hyun; Park, Jung-Keug; Cho, Hyunjin

    2014-10-01

    Human bone marrow-derived mesenchymal stem cells (hBM-MSCs) have been investigated as a new cell-therapeutic solution due to their capacity that could differentiate into neural-like cells. Extremely low-frequency electromagnetic fields (ELF-EMFs) therapy has emerged as a novel technique, using mechanical stimulus to differentiate hBM-MSCs and significantly enhance neuronal differentiation to affect cellular and molecular reactions. Magnetic iron oxide (Fe3O4) nanoparticles (MNPs) have recently achieved widespread use for biomedical applications and polyethylene glycol (PEG)-labeled nanoparticles are used to increase their circulation time, aqueous solubility, biocompatibility, and nonspecific cellular uptake as well as to decrease immunogenicity. Many studies have used MNP-labeled cells for differentiation, but there have been no reports of MNP-labeled neural differentiation combined with EMFs. In this study, synthesized PEG-phospholipid encapsulated magnetite (Fe3O4) nanoparticles are used on hBM-MSCs to improve their intracellular uptake. The PEGylated nanoparticles were exposed to the cells under 50 Hz of EMFs to improve neural differentiation. First, we measured cell viability and intracellular iron content in hBM-MSCs after treatment with MNPs. Analysis was conducted by RT-PCR, and immunohistological analysis using neural cell type-specific genes and antibodies after exposure to 50 Hz electromagnetic fields. These results suggest that electromagnetic fields enhance neural differentiation in hBM-MSCs incorporated with MNPs and would be an effective method for differentiating neural cells.

  5. Compilation of 1987 Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 2

    Science.gov (United States)

    1988-08-01

    mother bee is out of the nest on a pollen foraging trip, or on a round-leaf foraging trip just after laying her egg. Hypotheses Tested During the first...and pollen -foraging trips might decrease. Alternatively, bees could become disoriented or agitated in the field, so that their foraging trips increase...This was probably not enough additional resource to attract bees to the area . We hope that our efforts were not entirely in vain, since thistle seeds

  6. Compilation of 1987 Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 1

    Science.gov (United States)

    1988-08-01

    Apparently strong associations occur between A anni and eastern white pine, between amanita muscaria, boletus piDeratus, £in alboviolaceus, and T...bigtooth aspen/ ¥i = -3.864 + 1.032 BTA# .657 19.192 .001 Boletus piperatus ¥i = -1.334 + 18.587 BTABA .887 31.326 .005 bigtooth aspen/ Yi = -2.435 + 4.495... Boletus , Hebeloma, Paxillus or Suillus spp.; these have been designated as Type 6 mycorrhizae. Though variations occur within mycorrhizal morphology

  7. Extremely Low Frequency (ELF) Communications Program Non-Ionizing Electromagnetic Radiation Literature Evaluation and Assessment; 1977-1986 Literature Review.

    Science.gov (United States)

    1986-11-01

    Napoli, Italy, who tested the possible chromosomal abnormalities caused by a 50-Hz electric field. Bovine lymphocytes from peripheral blood were cultured...production, ’. mastitis , etc. The problem can be mitigated by improved grounding practices on farmsteads, and it is not directly relevant to ELFCSs. The

  8. Compilation of 1988 Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 3

    Science.gov (United States)

    1989-08-01

    Golden-cro:wmed Kinqlet 61 67 41 30 57 27 83 42 33 40 ReglIl satrapa Ruby-cro’ined Kinglet 23 9 6 1 5 0 1 2 Regulus calendula Eastern Bluebird 1 0 4 1I...callinao 3 American Woodcock 1 0 0 3 3 1 1 1 Scolooax minor Yello’-billea Cuckoo 0 11 Coccyzus americanus Great Horned 04i 0 1I Bubo virginianus Barred Oil ...Regulus calendula I Veery 4 2 11 10 10 5 2 2 0 0 Catharus fuscescens I Swainson’s Thrush 33 41 0 7 0 1 0 0 6 10 Catharus ustulatus I Hermit thrush 34 28

  9. Extremely Low Frequency (ELF) Propagation Formulas for Dipole Sources Radiating in a Spherical Earth-Ionosphere Waveguide

    National Research Council Canada - National Science Library

    Casey, Joseph

    2002-01-01

    .... In these formulas, the earth and ionosphere boundaries are modeled as scalar surface impedances. The spherical waveguide formulas are applied to predict the electromagnetic fields produced by vertical and horizontal electric dipoles...

  10. Compilation of 1987 Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 3

    Science.gov (United States)

    1988-08-01

    differences between exposure t.Npes. ke examined the .TL log to deterri ne the operational status of the antenna (mi. off. multiple on and offs during the da ...Foliage insects and fruit 14 Fruit 15 Foliage insects and seeds 16 Bark insects 17 Nectar and sap 18 Aquatic vegetation 19 Aquatic invertebrates C. Habitat...Coltsfoot Chamaedaphfle calyculata Petasites palmatus Bear Berry Dandelion Arctostaphylos uva -ursi Taraxacum officinale 122 Hawkweed Hieracium sp. 123

  11. NAS investigates ELF

    International Nuclear Information System (INIS)

    Gledhill, M.

    1997-01-01

    A report published in October 1996 by a committee appointed by the US National Research Council has concluded that 'no conclusive and consistent evidence shows that exposures to residential electric and magnetic fields produce cancer, adverse neurobehavioural effects, or reproductive and developmental effects'. However, the committee also noted that 'an association between residential wiring configurations ... and childhood leukemia persists in multiple studies, although the causative factor responsible for that statistical association has not been identified.' The committee was set up in 1991 at the request of the US Congress, and asked to concentrate on extremely low frequency (ELF) electric and magnetic field exposures found in residential settings. The expertise of its 16 members covered the wide range of disciplines necessary to evaluate the extensive research literature. Research into the possible health effects of ELF magnetic fields has been driven largely by epidemiology, and a comprehensive meta-analysis of 11 childhood leukemia studies forms a key part of the report. These studies have used several metrics to define 'exposure' of the study subjects to ELF fields. The meta-analysis combined the studies in a number of ways to evaluate their consistency and sensitivity to individual study results. (author). 1 ref

  12. Extremely low-frequency magnetic fields can impair spermatogenesis recovery after reversible testicular damage induced by heat.

    Science.gov (United States)

    Tenorio, Bruno Mendes; Ferreira Filho, Moisés Bonifacio Alves; Jimenez, George Chaves; de Morais, Rosana Nogueira; Peixoto, Christina Alves; Nogueira, Romildo de Albuquerque; da Silva Junior, Valdemiro Amaro

    2014-06-01

    Male infertility is often related to reproductive age couples experiencing fertility-related issues. Men may have fertility problems associated with reversible testicular damage. Considering that men have been increasingly exposed to extremely low-frequency magnetic fields generated by the production, distribution and use of electricity, this study analyzed whether 60 Hz and 1 mT magnetic field exposure may impair spermatogenesis recovery after reversible testicular damage induced by heat shock using rats as an experimental model. Adult male rats were subjected to a single testicular heat shock (HS, 43 °C for 12 min) and then exposed to the magnetic field for 15, 30 and 60 d after HS. Magnetic field exposure during the spermatogenesis recovery induced changes in testis components volume, cell ultrastructure and histomorphometrical parameters. Control animals had a reestablished and active spermatogenesis at 60 d after heat shock, while animals exposed to magnetic field still showed extensive testicular degeneration. Magnetic field exposure did not change the plasma testosterone. In conclusion, extremely low-frequency magnetic field may be harmful to fertility recovery in males affected by reversible testicular damage.

  13. Assessments and Viewpoints on the Biological and Human Health Effects of Extremely Low Frequency (ELF) Electromagnetic Fields. Compilation of Commissioned Papers for the ELF Literature Review Project.

    Science.gov (United States)

    1985-05-01

    E. Johnson. 1981. The effect of electromagnetic fields on alkaline phosphatase in clonal osteoblastic osteosarcoma cells. Rogers, L. E., J. L. Warren...F. von Recum, and J. B. Park. 1979. Effect of electrical stimulation of canine skin, and percutaneous device-skin interface healing. In Electrical

  14. Biological and Human Health Effects of Extremely Low Frequency Electromagnetic Fields. Post-1977 Literature Review.

    Science.gov (United States)

    1985-03-01

    dosimetric analysis for chick-brain exposure to radio frequencies. Using the geometrica assumptions of their S 51 0 0 : :-: analysis, an approximate...mass ratio used in Liboff’s calculations. Is the Liboff predication correct due to coincidence or is the relation between ions and surrounding...However, if correct , the explanation is incomplete insofar as 0 the same flux linkage has no reported effect at 16.66 Hz. Square wave rise times were not

  15. Parametric Modeling of Nerve Cell under the Sinusoidal Environmental 50 Hz Extremely Low Frequency Magnetic Fields

    Directory of Open Access Journals (Sweden)

    Homayoun Ebrahimian

    2013-06-01

    Full Text Available Background & Objectives: The development of technology has naturally given rise to an increase in environmental low-frequency electromagnetic fields and consequently has attracted scholars' attention. Most of the studies have focused on transmission lines and power system distribution with 50 Hz. This research is an attempt to show the effect of 50 Hz magnetic fields on bioelectric parameters and indicates the possible influence of this change in F1 cells of Helix aspersa .   Methods: The present research used Helix aspersa neuron F1 to identify the location of magnetic fields as well as the rate of effects of environmental magnetic fields on nervous system. Control group was used to study the effect of elapsed time, electrode entering and the cell membrane rupture. Intuition group and environmental group were considered in order to study the potential impact of interfering environmental factors and identify the effectiveness rate of magnetic fields, respectively. For the purpose of producing uniform magnetic field Helmholtz coil was used. Electrophysiological recording was realized under the requirements of current clamp. And, in order to show the impacts from magnetic fields on ion channels Hodgkin-Huxley cell model was applied. All data were analyzed taking the advantage of SPSS 16 software and two-way ANOVA statistical test. P < 0.05 was considered as significance level. And MATLAB software environment and PSO were used in order for applying the algorithm and estimating the parameters.   Result: No statistically significant difference was found between control and sham groups in different time intervals. Once the 45.87 microtesla was applied significant differences were observed 12 minutes after the application. The highest amount of change happened 14 minutes after the application of more fields. With the application of the field, the amplitude of the sodium action potential shows decreasing trend . No significant changes were observed in

  16. RESIDENTIAL EXPOSURE TO EXTREMELY LOW FREQUENCY ELECTRIC AND MAGNETIC FIELDS IN THE CITY OF RAMALLAH-PALESTINE.

    Science.gov (United States)

    Abuasbi, Falastine; Lahham, Adnan; Abdel-Raziq, Issam Rashid

    2018-04-01

    This study was focused on the measurement of residential exposure to power frequency (50-Hz) electric and magnetic fields in the city of Ramallah-Palestine. A group of 32 semi-randomly selected residences distributed amongst the city were under investigations of fields variations. Measurements were performed with the Spectrum Analyzer NF-5035 and were carried out at one meter above ground level in the residence's bedroom or living room under both zero and normal-power conditions. Fields' variations were recorded over 6-min and some times over few hours. Electric fields under normal-power use were relatively low; ~59% of residences experienced mean electric fields V/m. The highest mean electric field of 66.9 V/m was found at residence R27. However, electric field values were log-normally distributed with geometric mean and geometric standard deviation of 9.6 and 3.5 V/m, respectively. Background electric fields measured under zero-power use, were very low; ~80% of residences experienced background electric fields V/m. Under normal-power use, the highest mean magnetic field (0.45 μT) was found at residence R26 where an indoor power substation exists. However, ~81% of residences experienced mean magnetic fields residences showed also a log-normal distribution with geometric mean and geometric standard deviation of 0.04 and 3.14 μT, respectively. Under zero-power conditions, ~7% of residences experienced average background magnetic field >0.1 μT. Fields from appliances showed a maximum mean electric field of 67.4 V/m from hair dryer, and maximum mean magnetic field of 13.7 μT from microwave oven. However, no single result surpassed the ICNIRP limits for general public exposures to ELF fields, but still, the interval 0.3-0.4 μT for possible non-thermal health impacts of exposure to ELF magnetic fields, was experienced in 13% of the residences.

  17. Effects of extremely low frequency electromagnetic fields on paraoxonase serum activity and lipid peroxidation metabolites in rat.

    Science.gov (United States)

    Seifirad, Soroush; Farzampour, Shahrokh; Nourbakhsh, Mitra; Amoli, Mahsa Mohammad; Razzaghy-Azar, Maryam; Larijani, Bagher

    2014-01-01

    Atherogenic effects of ELF-MF exposure have not been studied well so far. Therefore we have hypothesized that ELF-MF exposure might have atherogenic effect by impairing antioxidant function and increasing lipid peroxidation. This study was therefore undertaken to examine the effects of ELF-MF on paraoxonase (PON) activity, antioxidant capacity and lipid peroxidation metabolites. Effects of time on remodeling of antioxidant system were also investigated in this study. Seventy five Wistar rats were randomly allocated into five groups as follows: 1) Sham exposure, 2) Single exposure to 60 Hz, sacrificed immediately after exposure, 3) Single exposure to 60 Hz, sacrificed 72 hours after exposure, 4) Fourteen days of exposure to 60 Hz, sacrificed immediately after exposure, and 5) Fourteen days of exposure to 60 Hz, sacrificed 72 hours after exposure. Blood samples were collected and analyzed. The results were compared using ANOVA and post hoc Tukey HSD for multiple caparisons. Single ELF-MF exposure significantly increased lipid peroxidation (CD and MDA) and increased antioxidant serum activity (HDL, paraoxonase activity, and serum total antioxidant capacity). Chronic ELF-MF exposure increased lipid peroxidation and affected antioxidant system. Free fatty acids levels were significantly increased after both single and two weeks exposure. Chronic exposure led to irreversible changes while acute exposure tended to reversible alterations on above mentioned parameters. According to the results of this study, ELF-MF exposure could impair oxidant-antioxidant function and might increase oxidative stress and lipid peroxidation. Antioxidant capability was dependent on the duration and continuity of ELF-MF exposure.

  18. Attenuation bands and cut-off frequencies for ELF electromagnetic waves

    International Nuclear Information System (INIS)

    Rauch, J.L.; Lefeuvre, F.; Cerisier, J.C.; Berthelier, J.J.; Boud'ko, N.; Michailova, G.; Kapustina, O.

    1985-01-01

    The propagation characteristic of ELF (10 Hz - 1500 Hz) electromagnetic waves observed on ARCAD 3, in three different zones: low L value (L 6). Unambiguous determinations of the wave normal directions are obtained from the interpretations of the measurements of four (3 magnetic, 1 electric) wave field components. The technique that is used, is based on the Means method in the cases of highly polarized waves and on the Storey and Lefeuvre WDF method in the other cases. A particular emphasis is put on the propagation characteristics of the waves, in a multiple ion plasma, and on the cut-off frequencies which appear at and below the local proton gyrofrequency

  19. 50Hz Extremely Low Frequency Electromagnetic Fields Enhance Protein Carbonyl Groups Content in Cancer Cells: Effects on Proteasomal Systems

    Directory of Open Access Journals (Sweden)

    A. M. Eleuteri

    2009-01-01

    Full Text Available Electromagnetic fields are an assessed cause of prolonging free radicals lifespan. This study was carried out to investigate the influence of extremely low frequency electromagnetic fields on protein oxidation and on the 20S proteasome functionality, the complex responsible for the degradation of oxidized proteins. Caco 2 cells were exposed, for 24–72 hours, to 1 mT, 50 Hz electromagnetic fields. The treatment induced a time-dependent increase both in cell growth and in protein oxidation, more evident in the presence of TPA, while no changes in cell viability were detected. Exposing the cells to 50 Hz electromagnetic fields caused a global activation of the 20S proteasome catalytic components, particularly evident at 72 hours exposure and in the presence of TPA. The finding that EGCG, a natural antioxidant compound, counteracted the field-related pro-oxidant effects demonstrates that the increased proteasome activity was due to an enhancement in intracellular free radicals.

  20. Numerical study of induced current perturbations in the vicinity of excitable cells exposed to extremely low frequency magnetic fields

    International Nuclear Information System (INIS)

    Hassan, Noha; Chatterjee, Indira; Publicover, Nelson G; Craviso, Gale L

    2003-01-01

    Realistic three-dimensional cell morphologies were modelled to determine the current density induced in excitable cell culture preparations exposed to 60 Hz magnetic fields and to identify important factors that can influence the responses of cells to these fields. Cell morphologies representing single spherical adrenal chromaffin cells, single elongated smooth muscle cells and chromaffin cell aggregates in a Petri dish containing culture medium were modelled using the finite element method. The computations for a spherical cell revealed alterations in the magnitude and spatial distribution of the induced current density in the immediate vicinity of the cell. Maxima occurred at the equatorial sides and minima at the poles. Proximity of cells to each other as well as cell aggregate shape, size and orientation with respect to the induced current influenced the magnitude and spatial distribution of the induced current density. For an elongated cell, effects on the induced current density were highly dependent on cell orientation with respect to the direction of the induced current. These results provide novel insights into the perturbations in induced current that occur in excitable cell culture preparations and lay a foundation for understanding the mechanisms of interaction with extremely low frequency magnetic fields at the tissue level

  1. Assessment of ELF magnetic fields produced by independent power lines

    International Nuclear Information System (INIS)

    Lucca, G.

    2008-01-01

    In this paper, the problem of assessing the ELF (extremely low-frequency) magnetic fields produced, in a certain area characterised by the presence of more than one independent power line, is faced. The use of the incoherent summation of the single contributions, as an advantageous estimator of the total magnetic field, is proposed and justified by means of a heuristic procedure. This kind of approach can be seen as a useful and practical tool to be employed in environmental impact analysis and in assessing long-term human exposure to ELF magnetic fields. (authors)

  2. High frequencies of elevated alkaline phosphatase activity and rickets exist in extremely low birth weight infants despite current nutritional support

    Science.gov (United States)

    Osteopenia and rickets are common among extremely low birth weight infants (ELBW, <1000 g birth weight) despite current practices of vitamin and mineral supplementation. Few data are available evaluating the usual course of markers of mineral status in this population. Our objectives in this study w...

  3. The Effect of Extremely Low Frequency Electromagnetic Fields on Visual Learning & Memory and Anatomical Structures of the Brain in Male Rhesus Monkeys

    Directory of Open Access Journals (Sweden)

    Elahe Tekieh

    2018-04-01

    Full Text Available Background: Humans in modern societies expose to substantially elevated levels of electromagnetic field (EMF emissions with different frequencies.The neurobiological effects of EMF have been the subject of debate and intensive research over the past few decades. Therefore, we evaluated the effects of EMF on visual learning and anatomical dimensions of the hippocampus and the prefrontal area (PFA in male Rhesus monkeys. Materials and Methods:In this study, four rhesus monkeys were irradiated by 0.7 microtesla ELF-EMF either at 5 or 30 Hz, 4 h a day, for 30 days. Alterations in visual learning and memory were assessed before and after irradiation phase by using a box designed that cchallenging animals for gaining rewards Also, the monkeys’ brains were scanned by using MRI technique one week before and one week after irradiation. The monkeys were anesthetized by intramuscular injection of ketamine hydrochloride (10–20 mg/kg and xylazine (0.2–0.4 mg/kg, and scanned with a 3-Tesla Magnetom, in axial, sagittal, and coronal planes using T2 weight­ed protocol with a slice thickness of 3 mm. The anatomical changes of hippocampus and the prefrontal area (PFA was measured by volumetric study. Results: Electromagnetic field exposure at a frequency of 30 Hz reduced the number of correct responses in the learning process and delayed memory formation in the two tested monkeys. While, ELF-EMF at 5 Hz had no effect on the visual learning and memory changes. No anatomical changes were found in the prefrontal area and the hippocampus at both frequencies. Conclusion: ELF-EMF irradiation at 30 Hz adversely affected visual learning and memory, pprobably through these changes apply through effects on other factors except changes in brain structure and anatomy.

  4. ELF exposure from mobile and cordless phones for the epidemiological MOBI-Kids study

    NARCIS (Netherlands)

    Calderón, Carolina; Ichikawa, Hiroki; Taki, Masao; Wake, Kanako; Addison, Darren; Mee, Terry; Maslanyj, Myron; Kromhout, Hans; Lee, Ae Kyoung; Sim, Malcolm R.; Wiart, Joe; Cardis, Elisabeth

    2017-01-01

    This paper describes measurements and computational modelling carried out in the MOBI-Kids case-control study to assess the extremely low frequency (ELF) exposure of the brain from use of mobile and cordless phones. Four different communication systems were investigated: Global System for Mobile

  5. The Source of Variation in Policies around the World: The Case of Protection of Human Health from Extremely Low Frequency Electromagnetic Fields

    International Nuclear Information System (INIS)

    Kandel, S.

    2006-01-01

    Scientific evidence supposedly plays a dominant role in environmental and public health regulation. This paper uses the example of Extremely Low Frequency Electromagnetic Fields regulation to test whether this is indeed the case. The paper first shows that there exists a significant variation in health protection policies for Extremely Low Frequencies Extremely Low Frequency Electromagnetic Fields around the world. Some countries adopt the international scientific-based guidelines while other countries choose to apply additional precautionary regulations of varying severity. Electromagnetic Fields policy makers around the world indicate that the Cost Benefit Analysis is one of the parameters considered for their choice among various policy options. A simple Cost Benefit Analysis framework is presented, utilizing scientific evidence on health risks from Extremely Low Frequencies as well as parameter values used in the Cost Benefit Analysis studies from California, Netherlands, Israel, and the United Kingdom to determine the justification of using several mitigation techniques. This Cost Benefit Analysis using data from the different countries leads to a clear conclusion: under all parameter values considered, only the low cost intervention measures, such as re-phasing and compacting lines, are justified. Re-routing lines, except in cases of very close proximity to residences, and under grounding existing lines cannot be justified due to the high costs involved and the small health benefits that are projected. Since the stringent policies cannot be accomplished with the low-cost measures, this suggests that if the Cost Benefit Analysis were indeed the basis for the policies implemented in different countries, one would expect a smaller variation in the worldwide policies observed today. The divergence between the policies that are implemented and those that can be supported by the Cost Benefit Analysis suggests that the Cost Benefit Analysis is either not used to

  6. The Comparative Study of the Effects of Extremely Low Frequency Electromagnetic Fields and Infrasound on Water Molecule Dissociation and Generation of Reactive Oxygen Species

    Science.gov (United States)

    2008-11-01

    ISTC Project No. #1592P The Comparative Study of The Effects of Extremely Low Frequency Electromagnetic Fields and Infrasound on Water Molecule...performed under the agreement with the International Science and Technology Center ( ISTC ), Moscow. REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704...dissociation and generation of reactive oxygen spaces. 5a. CONTRACT NUMBER ISTC Registration No: A-1592p 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

  7. Evaluation of changes in the behavior of the grey seal exposed to the electromagnetic field of extremely low frequencies (0.01–36 Hz

    Directory of Open Access Journals (Sweden)

    Yakovlev A. P.

    2016-03-01

    Full Text Available The paper presents the initial results of researching influence of low frequency electromagnetic field on the behavior of the grey seal. The authors have defined the frequency characteristics of the electromagnetic field which being exposed cause the changes in the behavior of the animal (the greatest deviation from the background values. The methodology of the experiment has been worked out and the criteria of evaluation of changes in the grey seal behavior in response to the electromagnetic field exposure with extremely low frequency characteristics have been proposed

  8. Penetration of ELF currents and electromagnetic fields into the Earth's equatorial ionosphere

    Science.gov (United States)

    Eliasson, B.; Papadopoulos, K.

    2009-10-01

    The penetration of extremely low frequency (ELF) transient electromagnetic fields and associated currents in the Earth's equatorial E-region plasma is studied theoretically and numerically. In the low-frequency regime, the plasma dynamics of the E-region is characterized by helicon waves since the ions are viscously coupled to neutrals while the electrons remain mobile. For typical equatorial E-region parameters, the plasma is magnetically insulated from penetration of very long timescale magnetic fields by a thin diffusive sheath. Wave penetration driven by a vertically incident pulse localized in space and time leads to both vertical penetration and the triggering of ELF helicon/whistler waves that carry currents obliquely to the magnetic field lines. The study presented here may have relevance for ELF wave generation by lightning discharges and seismic activity and can lead to new concepts in ELF/ULF injection in the earth-ionosphere waveguide.

  9. ELF-MF exposure affects the robustness of epigenetic programming during granulopoiesis

    Science.gov (United States)

    Manser, Melissa; Sater, Mohamad R. Abdul; Schmid, Christoph D.; Noreen, Faiza; Murbach, Manuel; Kuster, Niels; Schuermann, David; Schär, Primo

    2017-03-01

    Extremely-low-frequency magnetic fields (ELF-MF) have been classified as “possibly carcinogenic” to humans on the grounds of an epidemiological association of ELF-MF exposure with an increased risk of childhood leukaemia. Yet, underlying mechanisms have remained obscure. Genome instability seems an unlikely reason as the energy transmitted by ELF-MF is too low to damage DNA and induce cancer-promoting mutations. ELF-MF, however, may perturb the epigenetic code of genomes, which is well-known to be sensitive to environmental conditions and generally deranged in cancers, including leukaemia. We examined the potential of ELF-MF to influence key epigenetic modifications in leukaemic Jurkat cells and in human CD34+ haematopoietic stem cells undergoing in vitro differentiation into the neutrophilic lineage. During granulopoiesis, sensitive genome-wide profiling of multiple replicate experiments did not reveal any statistically significant, ELF-MF-dependent alterations in the patterns of active (H3K4me2) and repressive (H3K27me3) histone marks nor in DNA methylation. However, ELF-MF exposure showed consistent effects on the reproducibility of these histone and DNA modification profiles (replicate variability), which appear to be of a stochastic nature but show preferences for the genomic context. The data indicate that ELF-MF exposure stabilizes active chromatin, particularly during the transition from a repressive to an active state during cell differentiation.

  10. High frequencies of elevated alkaline phosphatase activity and rickets exist in extremely low birth weight infants despite current nutritional support

    Directory of Open Access Journals (Sweden)

    Parker Bruce R

    2009-07-01

    Full Text Available Abstract Background Osteopenia and rickets are common among extremely low birth weight infants (ELBW, Methods We evaluated all ELBW infants admitted to Texas Children's Hospital NICU in 2006 and 2007. Of 211 admissions, we excluded 98 patients who were admitted at >30 days of age or did not survive/stay for >6 weeks. Bone radiographs obtained in 32 infants were reviewed by a radiologist masked to laboratory values. Results In this cohort of 113 infants, P-APA was found to have a significant inverse relationship with BW, gestational age and serum phosphorus. In paired comparisons, P-APA of infants Conclusion Elevation of P-APA >600 IU/L was very common in ELBW infants. BW was significantly inversely related to both P-APA and radiologic rickets. No single value of P-APA was related to radiological findings of rickets. Given the very high risk of osteopenia and rickets among ELBW infants, we recommend consideration of early screening and early mineral supplementation, especially among infants

  11. LEVELS OF EXTREMELY LOW-FREQUENCY ELECTRIC AND MAGNETIC FIELDS FROM OVERHEAD POWER LINES IN THE OUTDOOR ENVIRONMENT OF RAMALLAH CITY-PALESTINE.

    Science.gov (United States)

    Abuasbi, Falastine; Lahham, Adnan; Abdel-Raziq, Issam Rashid

    2018-05-01

    In this study, levels of extremely low-frequency electric and magnetic fields originated from overhead power lines were investigated in the outdoor environment in Ramallah city, Palestine. Spot measurements were applied to record fields intensities over 6-min period. The Spectrum Analyzer NF-5035 was used to perform measurements at 1 m above ground level and directly underneath 40 randomly selected power lines distributed fairly within the city. Levels of electric fields varied depending on the line's category (power line, transformer or distributor), a minimum mean electric field of 3.9 V/m was found under a distributor line, and a maximum of 769.4 V/m under a high-voltage power line (66 kV). However, results of electric fields showed a log-normal distribution with the geometric mean and the geometric standard deviation of 35.9 and 2.8 V/m, respectively. Magnetic fields measured at power lines, on contrast, were not log-normally distributed; the minimum and maximum mean magnetic fields under power lines were 0.89 and 3.5 μT, respectively. As a result, none of the measured fields exceeded the ICNIRP's guidelines recommended for general public exposures to extremely low-frequency fields.

  12. Use of C. Elegans as a model organism for sensing the effects of ELF-EMFs

    Energy Technology Data Exchange (ETDEWEB)

    Lacchini, A H; Everington, M L; Augousti, A T; Walker, A J [School of Life Sciences, Kingston University London (United Kingdom)

    2007-07-15

    For the past two decades, there have been concerns and controversy about the effects on human health of the increased exposure to extremely-low-frequency (ELF) electromagnetic fields (EMFs) resulting from electrification, in both residential and industrial settings. Several epidemiological studies have implicated ELF-EMFs averaging 0.4 {mu}mUTesla (T) or more in increased risk of cancer, especially childhood leukaemia [1,2]; there have also been many reports demonstrating effects of power-frequency EMFs on cells [outlined in 1,3]. Unfortunately, however, the precise mechanisms by which ELF-EMFs exert biological effects have proven difficult to define and results of various studies have often been hard to reproduce [1]. We believe that C. elegans offers an exciting opportunity to elucidate the effects of power-frequency EMFs on cell signalling pathways within the whole organism and are therefore investigating the effects of ELF-EMF exposure on MAPK signalling in intact worms and fertilized embryos. Through taking a targeted approach to studying the effects of ELF-EMF's on MAPK signalling in C. elegans we aim to gather data that is physiologically relevant. Presently, this research is at a preliminary stage of preparation, and more detailed results on the exposure of Caenorhabditis elegans to ELF-EMF radiation will be presented at the conference itself.

  13. Frequency and characteristics of extremely low accumulation of 123I-metaiodobenzylguanidine (MIBG) in patients with and without cardiovascular diseases

    International Nuclear Information System (INIS)

    Sakata, Kazuyuki; Iida, Kei; Motiduki, Nao; Nakaya, Yoshihiro

    2008-01-01

    Very low accumulation of 123 I-metaiodobenzylguanidine (LoMIBG) in the human heart has been reported. This study assessed the frequency and characteristics of LoMIBG in the human heart. A total of 2212 patients (male/female ratio 1442/770, mean age 64±12 years) who underwent MIBG imaging were included. LoMIBG was defined as an initial heart-to-mediastinum (H/M) ratio of less than 1.4. Of the 114 patients with LoMIBG, 2 patients were excluded because of taking imipramine. Patients with LoMIBG were older than those without LoMIBG (P<0.0001). The main diagnosis and the number of patients with each disease were as follows: 28 of 410 coronary artery disease patients, 13 of 371 vasospastic angina patients, 3 of 86 various arrhythmias patients, 4 of 23 valvular heart disease patients, 9 of 101 dilated cardiomyopathy patients, 13 of 512 essential hypertension patients, 2 of 20 hypertrophic cardiomyopathy patients, 24 of 511 subjects without any definite disease (control), and 16 of 176 patients with miscellaneous diseases. When compared with patients without LoMIBG in each cardiovascular disease, LoMIBG patients had left ventricular function and frequency similar to critically ill patients. In the control group, the subjects with LoMIBG were significantly older (P<0.0001) and had significantly higher HF (P<0.03) and lower LF/HF (P<0.001) than those without LoMIBG. In addition, the incidence of LoMIBG was significantly elevated in the elderly (P<0.002). LoMIBG occurred in patients both with various diseases and without obvious diseases. Aging may be one of the mechanisms contributing to LoMIBG, especially in patients without obvious diseases. (author)

  14. Compilation of 1984 Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 1. TABS A-E.

    Science.gov (United States)

    1985-06-01

    parviforus 4.0 Trientalis borealis --- 7.9 Vaccinium membranaceum 4.2 3.3 Viburnum acerfolium --- 11.1 Waldsteinia fragaria --- 1.6 I ". r h m li mm...Templeton) Pseudachorutes spp. complex Isotoridae: Isotoma (Tesoria) nigrifrons Folsom 1. (Isotona) viridis Bourlet * FEntomobryidae: Tomocerus...67.1 66.4 66.9 71.9 Z 0. hexfasciata 16.4 13.2 17.6 14.2 N Isotomidae 50 36 84 67 % I. niarifrons 50.0 55.6 57.1 76.1 %I. viridis 50.0 44.4 42.9 23.9 N

  15. Compilation of Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 1. Tabs A-E.

    Science.gov (United States)

    1984-07-01

    Boletus piperatus Bull. ex Fr. +b Leccinum insigne Smith, Thiers, & Watling +b scabrum (Bull. ex Fr.) S.F. Gray +b subglabripes (Peck) Sing. + Suillus...bisporigera Atk. brUnnescens Atk. citrina (Schaeff ex ) S.F. Gray va~inta(Bull.ex Fr.) Vitt. Boletaceae Boletus pip -ratus Bull .ex Fr. Lrii,:termine-d "A

  16. Compilation of 1985 Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 3. Tabs H-J.

    Science.gov (United States)

    1986-07-01

    Buckley B. (1975) The Feen% P. (1970) Seasonal changes in oak leaf tannin processing of conifer and hardwood leaves in two and nutrients as a cause...Zonotrichia aIbicollis 35 51 34 77 -Drk-.yed Junco Junco hvermlis I I I I Red- wineed Blackbird Amelaius ohoeniceus 1 5 15 0 Comnon Grackle Ouiscalus cuiscula

  17. Compilation of 1986 Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 2. TABS D-G.

    Science.gov (United States)

    1987-07-01

    Control litter ’ and scil , 1984 and 1985. - ,** ’r:Ii. -"~~*jV’ 29 p -- ----- - p __0 e IN 30 preceded by a few days with lower or more variable...from leaf lizter, humus and scil . Pedobiol. 27: 293-29, 7ettel, J. 1984. The significance of tenterature and baronetric pressu re changes for the snow

  18. Compilation of Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program (1983). Volume 2. Tabs F-J.

    Science.gov (United States)

    1984-07-01

    POSITAE C. rugosa *Arctiumn minus CON VOLULACEAE * .Centaurea maculosa , Convolviliis Cirsium arvense (several possible) C. discolor CRASSULACEAE C. hill...Heracleum lanatumn A. umbllatusHieraciumn aurantiacum - A. sp. I H. florentinumn A. sp. 2 H. pratense A. sp. 3 Hypericumn perforatumn Centaurea maculosa H...Hypericumn perforatumn Aster umbellatus Lychnis alba Aster sp. I Melilotus alba *Centaurea maculosa Oenethera biennis Chrysanthemum leucanthemnum Prunus

  19. Compilation of 1985 Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 1. Tabs A-C.

    Science.gov (United States)

    1986-07-01

    cues (Barbour et al, 1980), has been used to quantitatively describe the herbaceous component of a northern hardwood forest (Mahall and Bormann, 1978...the influence of frag- mentation was eliminated for pine by discarding broken fascicles -53- upon retrival from the field. Nevertheless...alone and in comparison with the 1985 data). The same streptomycete mor- phological scheme used in 1985 will be emphasized in 1986. Root tip

  20. Compilation of 1986 Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 3. TABS H-J.

    Science.gov (United States)

    1987-07-01

    SLta Lii &4"Kg (?1I.WS tIW 蚌Z~ ~ ~ .. A~j’ 0Ś. Thm PruL 1*L*uY da U4- UW arm W"A * k~ ft.t . a*Ik L A Vm &’ we_ em_ do .f OWx*4 wk VIVW. *am...treatment transects. Among sFx-eis that were tested in .- "-- .a.’Sr WE nu, xANMw M"It6T U UPWTW rYW F-,T1., Mr~ T n- WVIn UVA V1w ?%n K’ -xr F 1flWW WVWWY...Fruit 15 Foliage insects and seeds 16 Bark insects 17 Nectar and sap 18 Aquatic vegetation 19 Aquatic invertebrates C. Habitat 1 Deciduous forest 2

  1. Sources of Exposure to ELF Fields at Workplaces (invited paper)

    International Nuclear Information System (INIS)

    Vecchia, P.

    1999-01-01

    In most workplaces people are exposed to a variety of extremely low frequency (ELF) fields. So-called 'electric jobs' have been identified, where the exposure is likely to significantly exceed average residential and occupational levels. The classification is, however, questionable, and no reliable exposure data may in general be associated with different jobs. Most recent epidemiological studies have been focused on areas where ELF fields are quite intense, sources are clearly identified, and actual field levels can be measured. Such areas include electric power generation, transmission and distribution, electric transport, and arc welding. In this paper, typical values of magnetic fields in these workplaces are presented and discussed. The time-weighted magnetic field values for the same jobs are not very consistent across the studies. This indicates that not only job titles, but also measurements of the magnetic field, are poor surrogates for the actual exposure, which is best assessed by the use of dosemeters. (author)

  2. Olfactory memory is enhanced in mice exposed to extremely low-frequency electromagnetic fields via Wnt/β-catenin dependent modulation of subventricular zone neurogenesis.

    Science.gov (United States)

    Mastrodonato, Alessia; Barbati, Saviana Antonella; Leone, Lucia; Colussi, Claudia; Gironi, Katia; Rinaudo, Marco; Piacentini, Roberto; Denny, Christine A; Grassi, Claudio

    2018-01-10

    Exposure to extremely low-frequency electromagnetic fields (ELFEF) influences the expression of key target genes controlling adult neurogenesis and modulates hippocampus-dependent memory. Here, we assayed whether ELFEF stimulation affects olfactory memory by modulating neurogenesis in the subventricular zone (SVZ) of the lateral ventricle, and investigated the underlying molecular mechanisms. We found that 30 days after the completion of an ELFEF stimulation protocol (1 mT; 50 Hz; 3.5 h/day for 12 days), mice showed enhanced olfactory memory and increased SVZ neurogenesis. These effects were associated with upregulated expression of mRNAs encoding for key regulators of adult neurogenesis and were mainly dependent on the activation of the Wnt pathway. Indeed, ELFEF stimulation increased Wnt3 mRNA expression and nuclear localization of its downstream target β-catenin. Conversely, inhibition of Wnt3 by Dkk-1 prevented ELFEF-induced upregulation of neurogenic genes and abolished ELFEF's effects on olfactory memory. Collectively, our findings suggest that ELFEF stimulation increases olfactory memory via enhanced Wnt/β-catenin signaling in the SVZ and point to ELFEF as a promising tool for enhancing SVZ neurogenesis and olfactory function.

  3. Chaos control and synchronization of two neurons exposed to ELF external electric field

    International Nuclear Information System (INIS)

    Wang Jiang; Zhang Ting; Che Yanqiu

    2007-01-01

    Chaos control and synchronization of two unidirectional coupled neurons exposed to ELF electrical field via nonlinear control technique is investigated. Based on results of space-time characteristics of trans-membrane voltage, the variation of cell trans-membrane voltage exposed to extremely low frequency (ELF) electric field is analyzed. The dynamical behaviors of the modified Hodgkin-Huxley (HH) model are identified under the periodic ELF electric field using both analytical and numerical analysis. Then, using the results of the analysis, a nonlinear feedback linearization control scheme and a modified adaptive control strategy are designed to synchronize the two unidirectional coupled neurons and stabilize the chaotic trajectory of the slave system to desired periodic orbit of the master system. The simulation results demonstrated the efficiency of the proposed algorithms

  4. Interaction of biological systems with static and ELF electric and magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, L.E.; Kelman, B.J.; Weigel, R.J. (eds.)

    1987-01-01

    Although background levels of atmospheric electric and geomagnetic field levels are extremely low, over the past several decades, human beings and other life forms on this planet have been subjected to a dramatically changing electromagnetic milieu. An exponential increase in exposure to electromagnetic fields has occurred, largely because of such technological advances as the growth of electrical power generation and transmission systems, the increased use of wireless communications, and the use of radar. In addition, electromagnetic field generating devices have proliferated in industrial plants, office buildings, homes, public transportation systems, and elsewhere. Although significant increases have occurred in electromagnetic field strenghths spanning all frequency ranges, this symposium addresses only the impact of these fields at static and extremely low frequencies (ELF), primarily 50 and 60 Hz. This volume contains the proceedings of the symposium entitled /open quotes/Interaction of biological systems with static and ELF electric and magnetic fields/close quotes/. The purpose of the symposium was to provide a forum for discussions of all aspects of research on the interaction of static and ELF electromagnetic fields with biological systems. These systems include simple biophysical models, cell and organ preparations, whole animals, and man. Dosimetry, exposure system design, and artifacts in ELF bioeffects research were also addressed, along with current investigations that examine fundamental mechanisms of interactions between the fields and biological processes. Papers are indexed separately.

  5. ELF magnetic therapy and oxidative balance.

    Science.gov (United States)

    Raggi, Francesco; Vallesi, Giuseppe; Rufini, Stefano; Gizzi, Stefania; Ercolani, Enrico; Rossi, Ruggero

    2008-01-01

    Knowledge about the relationship between exposure to extremely low-frequency (ELF) EMF and formation (or neutralization) of free radicals in the living cells is limited. Studies performed on animals and plants have shown conflicting effects on the relation between EMF and oxidative stress. Very few experiments have been performed on humans. The present study reports on the effects of an ELF magnetic therapy device (Seqex) on oxidative scale in humans. This device supplies complex magnetic signals with specific choices of frequency, intensity, and shape that are based on Liboff's ion cyclotron resonance hypothesis. Thirty-two healthy volunteers were treated using the Seqex cycle. A quantitative determination of oxidative stress was obtained at three time points by measuring Malondialdehyde (MDA) concentrations in peripheral blood before and after the cycle and one month following completion of the cycle. A highly significant reduction in mean MDA (53.8%, p = 0.0002) was found at the end of the treatment. One month later the mean MDA had again risen, but there was still a significant overall reduction of 15.6% (p = 0.010) compared to original values.

  6. A Novel Detection Method for Underwater Moving Targets by Measuring Their ELF Emissions with Inductive Sensors

    Directory of Open Access Journals (Sweden)

    Jinhong Wang

    2017-07-01

    Full Text Available In this article, we propose a novel detection method for underwater moving targets by detecting their extremely low frequency (ELF emissions with inductive sensors. The ELF field source of the targets is modeled by a horizontal electric dipole at distances more than several times of the targets’ length. The formulas for the fields produced in air are derived with a three-layer model (air, seawater and seafloor and are evaluated with a complementary numerical integration technique. A proof of concept measurement is presented. The ELF emissions from a surface ship were detected by inductive electronic and magnetic sensors as the ship was leaving a harbor. ELF signals are of substantial strength and have typical characteristic of harmonic line spectrum, and the fundamental frequency has a direct relationship with the ship’s speed. Due to the high sensitivity and low noise level of our sensors, it is capable of resolving weak ELF signals at long distance. In our experiment, a detection distance of 1300 m from the surface ship above the sea surface was realized, which shows that this method would be an appealing complement to the usual acoustic detection and magnetic anomaly detection capability.

  7. ULF/ELF Waves in Near-Moon Space

    Science.gov (United States)

    Nakagawa, Tomoko

    2016-02-01

    The reflection of the solar wind protons is equivalent to a beam injection against the solar wind flow. It is expected to produce a ring beam with a 3D distribution function in many cases. The reflected protons are responsible for the generation of ultra-low-frequency (ULF) waves at ˜0.01 Hz and narrowband waves at ˜1 Hz in the extremely low frequency (ELF) range through resonant interaction with magnetohydrodynamic waves and whistler mode waves in the solar wind, respectively. This chapter discusses these commonly observed waves in the near-Moon space. The sinusoidal waveforms and sharp spectra of the monochromatic ELF waves are impressive, but commonly observed are non-monochromatic waves in the ELF range ˜0.03-10 Hz. Some of the solar wind protons reflected by the dayside lunar surface or crustal magnetic field gyrate around the solar wind magnetic field and can access the center of the wake owing to the large Larmour radius.

  8. A survey of ELF and VLF research on lightning-ionosphere interactions and causative discharges

    Science.gov (United States)

    Inan, U. S.; Cummer, S. A.; Marshall, R. A.

    2010-06-01

    Extremely low frequency (ELF) and very low frequency (VLF) observations have formed the cornerstone of measurement and interpretation of effects of lightning discharges on the overlying upper atmospheric regions, as well as near-Earth space. ELF (0.3-3 kHz) and VLF (3-30 kHz) wave energy released by lightning discharges is often the agent of modification of the lower ionospheric medium that results in the conductivity changes and the excitation of optical emissions that constitute transient luminous events (TLEs). In addition, the resultant ionospheric changes are best (and often uniquely) observable as perturbations of subionospherically propagating VLF signals. In fact, some of the earliest evidence for direct disturbances of the lower ionosphere in association with lightning discharges was obtained in the course of the study of such VLF perturbations. Measurements of the detailed ELF and VLF waveforms of parent lightning discharges that produce TLEs and terrestrial gamma ray flashes (TGFs) have also been very fruitful, often revealing properties of such discharges that maximize ionospheric effects, such as generation of intense electromagnetic pulses (EMPs) or removal of large quantities of charge. In this paper, we provide a review of the development of ELF and VLF measurements, both from a historical point of view and from the point of view of their relationship to optical and other observations of ionospheric effects of lightning discharges.

  9. What advice to give when ELF is classified as a possible human carcinogen

    International Nuclear Information System (INIS)

    Repacholi, M.

    2002-01-01

    In 1996, the World Health Organization (WHO) established the International Electromagnetic Fields (EMF) Project to address the health issues associated with exposure to EMF. This Project is intended to provide independent scientific assessment of health effects from exposure to EMF (0-300 GHz); identify gaps in knowledge requiring further research in order to improve health risk assessments; encourage focused, high quality research; and conduct formal WHO/IARC/ICNIRP health risk assessments after key research has been completed. The International EMF Project is currently reviewing research results and conducting risk assessments of exposure to static and extremely low frequency (ELF) electric and magnetic fields. WHO will be conducting an evaluation of all health effects from ELF field exposure during 2002-3. This paper summarizes what is known about ELF exposure on childhood leukaemia, what the IARC classification means and how some national authorities have responded. In addition, WHO recommendations are given to provide guidance to national authorities wanting to protect their populations against EMF exposure. Whenever electricity is conducted through transmission lines, distribution lines or is used in appliances, both electric and magnetic fields exist close to the lines or appliances. The power frequency used is 50 or 60 Hz. Use of electric power has become part of everyday life. However, questions have been raised as to whether these and other ELF fields are carcinogenic or can produce any other effects on health

  10. Measurements of intermediate-frequency electric and magnetic fields in households

    NARCIS (Netherlands)

    Aerts, Sam; Calderon, Carolina; Valič, Blaž; Maslanyj, Myron; Addison, Darren; Mee, Terry; Goiceanu, Cristian; Verloock, Leen; Van den Bossche, Matthias; Gajšek, Peter; Vermeulen, Roel; Röösli, Martin; Cardis, Elisabeth; Martens, Luc; Joseph, Wout

    Historically, assessment of human exposure to electric and magnetic fields has focused on the extremely-low-frequency (ELF) and radiofrequency (RF) ranges. However, research on the typically emitted fields in the intermediate-frequency (IF) range (300Hz to 1MHz) as well as potential effects of IF

  11. Effects of repeated 9 and 30-day exposure to extremely low-frequency electromagnetic fields on social recognition behavior and estrogen receptors expression in olfactory bulb of Wistar female rats.

    Science.gov (United States)

    Bernal-Mondragón, C; Arriaga-Avila, V; Martínez-Abundis, E; Barrera-Mera, B; Mercado-Gómez, O; Guevara-Guzmán, R

    2017-02-01

    We investigated the short- and long-term effects of extremely low-frequency electromagnetic fields (EMF) on social recognition behavior and expression of α- and β-estrogen receptors (ER). Rats were exposed to 60-Hz electromagnetic fields for 9 or 30 days and tested for social recognition behavior. Immunohistochemistry and western blot assays were performed to evaluate α- and β-ER expression in the olfactory bulb of intact, ovariectomized (OVX), and ovariectomized+estradiol (E2) replacement (OVX+E2). Ovariectomization showed impairment of social recognition after 9 days of EMF exposure and a complete recovery after E2 replacement and so did those after 30 days. Short EMF exposure increased expression of β-ER in intact, but not in the others. Longer exposure produced a decrease in intact but an increase in OVX and OVX+E2. Our findings suggest a significant role for β-estrogen receptors and a lack of effect for α-estrogen receptors on a social recognition task. EMF: extremely low frequency electromagnetic fields; ERs: estrogen receptors; OB: olfactory bulb; OVX: ovariectomized; OVX + E 2 : ovariectomized + estradiol replacement; IEI: interexposure interval; β-ER: beta estrogen receptor; E 2 : replacement of estradiol; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; WB: Western blot; PBS: phosphate-buffer saline; PB: phosphate-buffer.

  12. Artificial neural networks to estimate the EMF ELF on car travelling near power transmission line

    Energy Technology Data Exchange (ETDEWEB)

    Al-Sayegh, O.A.; Qabazard, A.M. [Kuwait Inst. for Scientific Research, Safat (Kuwait). advanced Systems Division of Environment and Urban

    2007-07-01

    An artificial neural network (ANN) was developed to determine the electromagnetic field (EMF) and extremely low frequency (ELF) intensity on a vehicle body at different distances from a high tension power line and at varying power loads. EMF radiated emissions from ELF source power transmission lines can produce interference in the electric components in vehicles traveling at variable speed near the power lines. The passengers in the vehicle may also experience EMF-related health problems. Although EMF has been recently categorized as a new form of pollution, the situation has been largely ignored by the industry. Typically, electromagnetic fields at different frequencies show the fastest growing environmental influences. All populations are now exposed to varying degrees of EMF and the levels will continue to increase as technology advances. The purpose of this work was to promote discussion and help find design solutions to manufacture a new device for measuring the EMF at variable speed. In this study, a set of near field measurements outside the vehicle were used to train ANN. Estimations of the EMF ELF for various distances from the high tension power line were presented. It was determined that the most important factors affecting the electric field model include exposure conditions; size, shape and position of the exposed body in the field; and, surface charge density. The EMF ELF was found to increase near sagging areas of the overhead power transmission line. The EMF ELF was found to be proportional to the total amps flowing through the line at the time of measurement. 14 refs., 3 figs.

  13. Investigations of Relatively Easy To Construct Antennas With Efficiency in Receiving Schumann Resonances: Preparations for a Miniaturized Reconfigurable ELF Receiver

    Science.gov (United States)

    Farmer, Brian W.; Hannan, Robert C.

    2003-01-01

    Relatively little is known about the cavity between the Earth and the ionosphere, which opens opportunities for technological advances and unique ideas. One effective means to study this cavity is with extremely low frequency (ELF) antennas. Possible applications of these antennas are global weather prediction, earthquake prediction, planetary exploration, communication, wireless transmission of power, or even a free energy source. The superconducting quantum interference device SQUID) and the coil antenna are the two most acceptable receivers discovered for picking up ELF magnetic fields. Both antennas have the potential for size reduction, allowing them to be portable enough for access to space and even for personal ware. With improvements of these antennas and signal processing, insightful analysis of Schumann resonance (SR) can give the science community a band of radio frequency (RF) signals for improving life here on Earth and exploring beyond.

  14. Cytogenetic damage in adult and newborn mice exposed to Elf magnetic fields

    International Nuclear Information System (INIS)

    Ieradi, L.A.; Udroiu, I.; Chiuchiarelli, G.; Migliorini, D.; Cristaldi, M.; Tanzarella, C.

    2006-01-01

    Data obtained in newborn mice show that the chronic exposure during intra-uterine life to a 50 Hz, 650 μT E.L.F. magnetic field induce a genetic damage. Nevertheless, the increase of DNA strand break in brain and in micronuclei frequency in peripheral blood and liver disagree with the data obtained by Abramsson-Zetterberg and Grawe (13) which did not find any genetic alterations in mice exposed to extremely low frequency (E.L.F.) magnetic field. In any case, along with other dissimilarities in the experimental design, the intensity of the field (14 μT) and the time of sampling (35 days) were different. It is important to underline the four-fold increase in C.R.E.S.T.+ micronuclei frequency in circulating erythrocytes in the exposed group in comparison with the control group. Even though this value is quite low, it could indicate that E.L.F. magnetic fields may have different properties to damage the genome integrity. This stresses the need for further investigation on the possible link between electromagnetic fields and aneuploidy in order to elucidate the relationship with carcinogenesis. Preliminary data obtained with sperm abnormality assay show a significant increase of sperm abnormalities in mice exposed to E.L.F. magnetic fields and suggest a possible alteration to the spermatogenic process after exposure. This data agrees with data obtained by Tablado et al. (1998), in mice exposed continually for 35 days to a field of 1 T. Regarding the palatal ridges alterations assay, the results obtained show that the development of the secondary palate is not affected by E.L.F. magnetic field (50 Hz, 0,65 T). Nevertheless further studies at different frequency and intensity should be carried out to detect the possible epigenetic damage induced by E.L.F. exposure (Migliorini, 2005). With regard to the mechanism of action, it is generally believed that the damage induced by the magnetic field is an oxidative damage and that free radicals are involved. Some authors

  15. Cytogenetic damage in adult and newborn mice exposed to Elf magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Ieradi, L.A. [Istituto per lo Studio degli Ecosistemi, CNR, Rome (Italy); Udroiu, I.; Chiuchiarelli, G.; Migliorini, D.; Cristaldi, M. [Universite La Sapienza, Dipt. di Biologia Animale e dell' Uomo, Rome (Italy); Tanzarella, C. [Roma Univ., Dipt. di Biologia (Italy)

    2006-07-01

    Data obtained in newborn mice show that the chronic exposure during intra-uterine life to a 50 Hz, 650 {mu}T E.L.F. magnetic field induce a genetic damage. Nevertheless, the increase of DNA strand break in brain and in micronuclei frequency in peripheral blood and liver disagree with the data obtained by Abramsson-Zetterberg and Grawe (13) which did not find any genetic alterations in mice exposed to extremely low frequency (E.L.F.) magnetic field. In any case, along with other dissimilarities in the experimental design, the intensity of the field (14 {mu}T) and the time of sampling (35 days) were different. It is important to underline the four-fold increase in C.R.E.S.T.+ micronuclei frequency in circulating erythrocytes in the exposed group in comparison with the control group. Even though this value is quite low, it could indicate that E.L.F. magnetic fields may have different properties to damage the genome integrity. This stresses the need for further investigation on the possible link between electromagnetic fields and aneuploidy in order to elucidate the relationship with carcinogenesis. Preliminary data obtained with sperm abnormality assay show a significant increase of sperm abnormalities in mice exposed to E.L.F. magnetic fields and suggest a possible alteration to the spermatogenic process after exposure. This data agrees with data obtained by Tablado et al. (1998), in mice exposed continually for 35 days to a field of 1 T. Regarding the palatal ridges alterations assay, the results obtained show that the development of the secondary palate is not affected by E.L.F. magnetic field (50 Hz, 0,65 T). Nevertheless further studies at different frequency and intensity should be carried out to detect the possible epigenetic damage induced by E.L.F. exposure (Migliorini, 2005). With regard to the mechanism of action, it is generally believed that the damage induced by the magnetic field is an oxidative damage and that free radicals are involved. Some authors

  16. Properties of ELF electromagnetic waves in and above the earth's ionosphere deduced from plasma wave experiments on the OV1-17 and Ogo 6 satellites

    International Nuclear Information System (INIS)

    Kelley, M.C.; Tsurutani, B.T.; Mozer, F.S.

    1975-01-01

    An analysis of ac electric field data obtained on board the OV1-17 satellite and ac magnetic field data obtained on board the Ogo 6 satellite has been made during the northern hemisphere spring and summer of 1969 with the purpose of studying extreme low frequency (ELF) electromagnetic waves above the earth's ionosphere. The results are in basic agreement with a number of previous ground-based and low-altitude satellite experiments in that the peak signal was observed at high latitudes outside the statistical location of the plasmapause on the day side of the earth, that ELF chorus was very often observed in conjunction with the steady ELF hiss emissions, that the winter hemisphere signal was considerably smaller than that observed in summer or in equinoctial months, and that the emission strength and region of occurrence are asymmetric about magnetic noon. Observations of such strong hiss signals outside the plasmasphere are somewhat surprising in light of Ogo 3 and Ogo 5 measurements which show steady ELF hiss to be closely confined to the plasmasphere at high altitudes during normal circumstances. The present study supports the hypothesis that hiss leaks out of the plasmasphere and refracts downward into the lower ionosphere; such a model predicts the observed summer-winter asymmetry and the poleward skewing of the ELF peak signal strength with decreasing altitude

  17. Exposure of ELF-EMF and RF-EMF Increase the Rate of Glucose Transport and TCA Cycle in Budding Yeast.

    Science.gov (United States)

    Lin, Kang-Wei; Yang, Chuan-Jun; Lian, Hui-Yong; Cai, Peng

    2016-01-01

    In this study, we investigated the transcriptional response to 50 Hz extremely low frequency electromagnetic field (ELF-EMF) and 2.0 GHz radio frequency electromagnetic field (RF-EMF) exposure by Illumina sequencing technology using budding yeast as the model organism. The transcription levels of 28 genes were upregulated and those of four genes were downregulated under ELF-EMF exposure, while the transcription levels of 29 genes were upregulated and those of 24 genes were downregulated under RF-EMF exposure. After validation by reverse transcription quantitative polymerase chain reaction (RT-qPCR), a concordant direction of change both in differential gene expression (DGE) and RT-qPCR was demonstrated for nine genes under ELF-EMF exposure and for 10 genes under RF-EMF exposure. The RT-qPCR results revealed that ELF-EMF and RF-EMF exposure can upregulate the expression of genes involved in glucose transportation and the tricarboxylic acid (TCA) cycle, but not the glycolysis pathway. Energy metabolism is closely related with the cell response to environmental stress including EMF exposure. Our findings may throw light on the mechanism underlying the biological effects of EMF.

  18. On precursory ULF/ELF electromagnetic signatures for the Kobe earthquake on April 12, 2013

    Science.gov (United States)

    Schekotov, A.; Izutsu, J.; Hayakawa, M.

    2015-12-01

    After the 2011 Tohoku earthquake (EQ), there have been numerous aftershocks in the eastern and Pacific Ocean of Japan, but EQs are still rare in the western part of Japan. In this situation a relatively large (magnitude (M) ∼ 6) EQ happened on April 12 (UT), 2013 at a place close to the 1995 Kobe EQ (M ∼ 7), so we have tried to find whether there existed any electromagnetic precursors to this EQ. Two precursory signatures are detected: one is the depression of ULF (ultra-low-frequency, 0.01-0.02 Hz) geomagnetic variations on April 9, and the second is wideband ELF (extremely low frequency) electromagnetic radiation on April 11. These results for the 2013 Kobe EQ are compared with the corresponding results for the former 1995 Kobe EQ.

  19. Extremely low temperature properties of epoxy GFRP

    International Nuclear Information System (INIS)

    Kadotani, Kenzo; Nagai, Matao; Aki, Fumitake.

    1983-01-01

    The examination of fiber-reinforced plastics, that is, plastics such as epoxy, polyester and polyimide reinforced with high strength fibers such as glass, carbon, boron and steel, for extremely low temperature use began from the fuel tanks of rockets. Therafter, the trial manufacture of superconducting generators and extremely low temperature transformers and the manufacture of superconducting magnets for nuclear fusion experimental setups became active, and high performance FRPs have been adopted, of which the extremely low temperature properties have been sufficiently grasped. Recently, the cryostats made of FRPs have been developed, fully utilizing such features of FRPs as high strength, high rigidity, non-magnetic material, insulation, low heat conductivity, light weight and the freedom of molding. In this paper, the mechanical properties at extremely low temperature of the plastic composite materials used as insulators and structural materials for extremely low temperature superconducting equipment is outlined, and in particular, glass fiber-reinforced epoxy laminates are described somewhat in detail. The fracture strain of GFRP at extremely low temperature is about 1.3 times as large as that at room temperature, but at extremely low temperature, clear cracking occurred at 40% of the fracture strain. The linear thermal contraction of GFRP showed remarkable anisotropy. (Kako, I.)

  20. Background ELF magnetic fields in incubators: a factor of importance in cell culture work.

    Science.gov (United States)

    Mild, Kjell Hansson; Wilén, Jonna; Mattsson, Mats-Olof; Simko, Myrtill

    2009-07-01

    Extremely low frequency (ELF) magnetic fields in cell culture incubators have been measured. Values of the order of tens of muT were found which is in sharp contrast to the values found in our normal environment (0.05-0.1microT). There are numerous examples of biological effects found after exposure to MF at these levels, such as changes in gene expression, blocked cell differentiation, inhibition of the effect of tamoxifen, effects on chick embryo development, etc. We therefore recommend that people working with cell culture incubators check for the background magnetic field and take this into account in performing their experiments, since this could be an unrecognised factor of importance contributing to the variability in the results from work with cell cultures.

  1. Synchronization control of Hodgkin-Huxley neurons exposed to ELF electric field

    International Nuclear Information System (INIS)

    Che Yanqiu; Wang Jiang; Zhou Sisi; Deng Bin

    2009-01-01

    This paper presents an adaptive neural network H ∞ control for unidirectional synchronization of modified Hodgkin-Huxley (HH) neurons exposed to extremely low frequency (ELF) electric field. The proposed modified HH neurons exhibit periodic and chaotic dynamics in response to sinusoidal electric field stimulation. Based on the Lyapunov stability theory, we derive the updated laws of neural network for approximating the nonlinear uncertain functions of the error dynamical system. The H ∞ design technique makes the controller robust to unmodeled dynamics, disturbances and approximate errors. The proposed controller not only ensures closed-loop stability, but also guarantees an H ∞ performance for the synchronization error system. The states of the controlled slave system exponentially synchronize with that of the master one after control. The simulation results demonstrate the validity of the proposed method.

  2. ELF radiation from the Tromsoe super heater facility

    International Nuclear Information System (INIS)

    Barr, R.; Stubbe, P.

    1991-01-01

    Direct comparisons have been made of the ionospheric ELF radiation produced by the new (1 GW ERP) and old (250 MW ERP) antennas of the Tromsoe heater system, but no significant differences in the ELF signal strength have been detected. This initially surprising result is shown to require a value of unity for the index relating the received ELF signal strength to HF power input to the antenna. A series of experiments performed solely to derive more accurate values for this power index provided values ranging from 0.74 to 0.97, dependent on the ELF frequencies generated. It has been suggested that ELF radiation from the normal Tromsoe heater facility should be limited by saturation effects, even when operating well below the maximum HF power density (3mW/m 2 in the D-region). No evidence for such saturation effects has been found even at power densities greater than 10mW/m 2

  3. Global thunderstorm activity estimation based on number of transients in ELF-band

    Science.gov (United States)

    Ondraskova, Adriena; Sevcik, Sebastian

    2017-04-01

    Schumann resonances (SR) are resonant electromagnetic oscillations in extremely low frequency band (ELF, 3 Hz - 3 kHz), which arise in the Earth-ionosphere cavity due to lightning activity in planetary range. The time records in the ELF-band consist of background signals and ELF transients/Q-bursts superimposed on the background exceeding it by a factor of 5 - 10. The former are produced by the common worldwide thunderstorm activity (100 - 150 events per second), the latter origin from individual intense distant lightning discharges (100 - 120 powerful strokes per hour). A Q-burst is produced by a combination of direct and antipodal pulses and the decisive factor for its shape follows from the source-to-observer distance. Diurnal/seasonal variations of global thunderstorm activity can be deduced from spectral amplitudes of SR modes. Here we focus on diurnal/seasonal variations of the number of ELF-transients assuming that it is another way of lightning activity estimation. To search for transients, our own code was applied to the SR vertical electric component measured in October 2004 - October 2008 at the Astronomical and Geophysical Observatory of FMPI CU, Slovakia. Criteria for the identification of the burst are chosen on the basis of the transient amplitudes and their morphological features. Monthly mean daily variations in number of transients showed that African focus dominates at 14 - 16 h UT and it is more active in comparison with Asian source, which dominates at 5 - 8 h UT in dependence on winter or summer month. American source had surprisingly slight response. Meteorological observations in South America aiming to determine lightning hotspots on the Earth indicate that flash rate in this region is greatest during nocturnal 0 h - 3 h local standard time. This fact may be interpreted that Asian and South American sources contribute together in the same UT. Cumulative spectral amplitude of the first three SR modes compared with number of ELF-transients in

  4. Evaluation of occupational exposure to ELF magnetic fields at power plants in Greece in the context of European directives

    International Nuclear Information System (INIS)

    Christopoulou, Maria; Govari, Chrysa; Tsaprouni, Panagiota; Karabetsos, Efthymios

    2015-01-01

    The scope of this paper is to comparatively present the extremely low-frequency (ELF) measurements performed at four power plants in Greece, focusing on: (a) the worst-case exposure conditions, (b) the existence of magnetic field harmonic components, (c) the technical similarities among the power plants and (d) comparison of the measured percentages of reference levels at typical working areas in the power plants. A detailed measurement methodology is proposed, including broadband on-site inspection of the working areas, weighted averaged root-mean-square and peak values of magnetic flux density, percentage of reference levels, according to 1998 ICNIRP guidelines and harmonic analysis of the multi-frequency magnetic fields. During the analysis of the occupational exposure in all power plants, the new Directive 2013/35/EU has been taken into account. The study concludes by proposing a mapping procedure of working areas into certain zones, in order to take measures for workers safety. (authors)

  5. Design and fabrication of a microplatform for the proximity effect study of localized ELF-EMF on the growth of in vitro HeLa and PC-12 cells

    International Nuclear Information System (INIS)

    Chen, Y C; Chen, C C; Cheng, Y T; Tu, W; Tseng, F G

    2010-01-01

    This paper presents a platform technology with experimental results that show the scientists and biologists a way to rapidly investigate and analyze the biological effects of localized extremely low frequency (ELF) electromagnetic field (EMF) on living cells. The proximity effect of the localized ELF-EMF on living cells is revealed using the bio-compatible microplatform on which an on-glass inductive coil array, the source of the localized ELF-EMF in micro scale, is designed, fabricated and operated with a field strength of 1.2 ± 0.1 mT at 60 Hz for cell culturing study. After a 72 h ELF-EMF exposure, HeLa (human cervical cancer) and PC-12 (rat pheochromocytoma) cells exhibit about 18.4% and 12.9% cell proliferation rate reduction, respectively. Furthermore, according to the presented dynamic model, the reduction of the proliferation can be attributed to the interference of signal transduction processes due to the tangential currents induced around the cells

  6. Exposure to power frequency magnetic fields suppresses X-ray-induced apoptosis transiently in Ku80-deficient xrs5 cells

    International Nuclear Information System (INIS)

    Tian, Furong; Nakahara, Takehisa; Yoshida, Masami; Honda, Naoko; Hirose, Hideki; Miyakoshi, Junji

    2002-01-01

    In an attempt to determine whether exposure to extremely low frequency (ELF) electromagnetic fields can affect cells, Ku80-deficient cells (xrs5) and Ku80-proficient cells (CHO-K1) were exposed to ELF electromagnetic fields. Cell survival, and the levels of the apoptosis-related genes p21, p53, phospho-p53 (Ser 15 ), caspase-3 and the anti-apoptosis gene bcl-2 were determined in xrs5 and CHO-K1 cells following exposure to ELF electromagnetic fields and X-rays. It was found that exposure of xrs5 and CHO-K1 cells to 60 Hz ELF electromagnetic fields had no effect on cell survival, cell cycle distribution and protein expression. Exposure of xrs5 cells to 60 Hz ELF electromagnetic fields for 5 h after irradiation significantly inhibited G 1 cell cycle arrest induced by X-rays (1 Gy) and resulted in elevated bcl-2 expression. A significant decrease in the induction of p53, phospho-p53, caspase-3 and p21 proteins was observed in xrs5 cells when irradiation by X-rays (8 Gy) was followed by exposure to 5 mT ELF magnetic fields. Exposure of xrs5 cells to the ELF electromagnetic fields for 10 h following irradiation significantly decreased X-ray-induced apoptosis from about 1.7% to 0.7%. However, this effect was not found in CHO-K1 cells within 24 h of irradiation by X-rays alone and by X-rays combined with ELF electromagnetic fields. Exposure of xrs5 cells to 60 Hz ELF electromagnetic fields following irradiation can affect cell cycle distribution and transiently suppress apoptosis by decreasing the levels of caspase-3, p21, p53 and phospho-p53 and by increasing bcl-2 expression

  7. TRI-SERVICE ELF COMMUNICATIONS - VOL. II, BIBLIOGRAPHY.

    Science.gov (United States)

    BIBLIOGRAPHIES, UNDERGROUND ANTENNAS , ELECTRICAL RESISTANCE, UNDERGROUND , COSTS, VERY LOW FREQUENCY, LOW FREQUENCY, PROPAGATION, NOISE(RADIO)....EXTREMELY LOW FREQUENCY), (*COMMAND AND CONTROL SYSTEMS, COMMUNICATION AND RADIO SYSTEMS), (* COMMUNICATION AND RADIO SYSTEMS, MILITARY RESEARCH

  8. The peculiarities of power terrestrial ELF emission in the Earth's ionosphere

    Science.gov (United States)

    Korepanov, Valery; Dudkin, Fedir; Pronenko, Vira; Chvach, Valery

    2016-04-01

    The near-Earth space is saturated with electromagnetic (EM) waves of terrestrial origin in a wide frequency range. The most powerful natural sources of EM emission are thunderstorms and triggered by them Schumann resonance (SR) radiation which is the narrowband EM noise that occurs due to the global thunderstorm activity in the Earth-ionosphere cavity in frequency range about 7-100 Hz. The considerable part of the terrestrial EM emission belongs to everyday human activity which increases year by year with unpredictable consequences. At the beginning of space exploration era it was considered that high frequency EM waves freely penetrate through the Earth's ionosphere, but the terrestrial EM emission below very low frequency range is limited by ionospheric F2 layer boundary due to great EM losses in plasma. About 40 years ago the power lines harmonic radiation (multiple of 50/60 Hz) was found at satellite observations in a few kilohertz range, nevertheless the ionosphere was considered fully opaque for extremely low frequency (ELF) EM emission. However recently, in spite of theoretical estimations, the SR harmonics and power line emission (PLE) 50/60 Hz were discovered during flights of low Earth orbiting satellites C/NOFS (Simões et al., 2011) and Chibis-M (Dudkin et al., 2015) at heights 400-800 km, i.e. over F2-layer. Last results are a great challenge to the theory of ELF EM emission propagation in the Earth's ionosphere as well as for study of long-term influence of constantly increasing electric energy consumption by human civilization in the Earth's environment. We present the analysis of the space and time distribution for observed PLE and SR harmonics, their connection with power terrestrial sources of ELF emission and possible relation between measured values and ionosphere conditions. Also some electromagnetic parameters have been estimated. Simões, F. A., R. F. Pfaff, and H. T. Freudenreich (2011), Satellite observations of Schumann resonances in the

  9. Extreme low temperature tolerance in woody plants

    Directory of Open Access Journals (Sweden)

    George Richard Strimbeck

    2015-10-01

    Full Text Available Woody plants in boreal to arctic environments and high mountains survive prolonged exposure to temperatures below -40˚C and minimum temperatures below -60˚C, and laboratory tests show that many of these species can also survive immersion in liquid nitrogen at -196˚C. Studies of biochemical changes that occur during acclimation, including recent proteomic and metabolomic studies, have identified changes in carbohydrate and compatible solute concentrations, membrane lipid composition, and proteins, notably dehydrins, that may have important roles in survival at extreme low temperature. Consideration of the biophysical mechanisms of membrane stress and strain lead to the following hypotheses for cellular and molecular mechanisms of survival at extreme low temperature: 1. Changes in lipid composition stabilize membranes at temperatures above the lipid phase transition temperature (-20 to 30˚C, preventing phase changes that result in irreversible injury. 2. High concentrations of oligosaccharides promote vitrification or high viscosity in the cytoplasm in freeze-dehydrated cells, which would prevent deleterious interactions between membranes. 3. Dehydrins bind membranes and further promote vitrification or act stearically to prevent membrane-membrane interactions.

  10. Assessing occupational and domestic ELF magnetic field exposure in the UK Adult Brain Tumour Study: Results of a feasibility study

    International Nuclear Information System (INIS)

    Van Tongeren, M.; Mee, T.; Whatmough, P.; Broad, L.; Mashlanyj, M.; Allen, S.; Muir, K.; McKinney, P.

    2004-01-01

    The feasibility of measuring exposure to extremely low frequency magnetic fields (ELF MF) in the UK Adult Brain Tumour Study (UKABTS) was examined. During the study, 81 individuals and 30 companies were approached with 79 individuals and 25 companies agreeing to participate. Exposure data were collected using EMDEX II dosemeters worn by the participants for 3-4 consecutive days. Data were collected over a total of 321 d, including non-occupational periods. The results showed occupational exposure to be the main determinant of overall exposure. Moderate to strong correlations were found between arithmetic mean exposure and all other metrics with the possible exception of maximum exposure. Significant differences in exposure were found between job categories with large variability in certain categories. Highest average exposures were found for security officers (arithmetic mean, AM: 0.78 μT), secretaries (AM: 0.48 μT) and dentists (AM: 0.42 μT). Welding and working near high-voltage power lines were associated with elevated exposure. In summary, acceptably precise measures of ELF MF exposure are feasible at relatively moderate cost. The results were used to develop a protocol for data collection from subjects in the UKABTS. (authors)

  11. Indoor transformer stations and ELF magnetic field exposure: use of transformer structural characteristics to improve exposure assessment.

    Science.gov (United States)

    Okokon, Enembe Oku; Roivainen, Päivi; Kheifets, Leeka; Mezei, Gabor; Juutilainen, Jukka

    2014-01-01

    Previous studies have shown that populations of multiapartment buildings with indoor transformer stations may serve as a basis for improved epidemiological studies on the relationship between childhood leukaemia and extremely-low-frequency (ELF) magnetic fields (MFs). This study investigated whether classification based on structural characteristics of the transformer stations would improve ELF MF exposure assessment. The data included MF measurements in apartments directly above transformer stations ("exposed" apartments) in 30 buildings in Finland, and reference apartments in the same buildings. Transformer structural characteristics (type and location of low-voltage conductors) were used to classify exposed apartments into high-exposure (HE) and intermediate-exposure (IE) categories. An exposure gradient was observed: both the time-average MF and time above a threshold (0.4 μT) were highest in the HE apartments and lowest in the reference apartments, showing a statistically significant trend. The differences between HE and IE apartments, however, were not statistically significant. A simulation exercise showed that the three-category classification did not perform better than a two-category classification (exposed and reference apartments) in detecting the existence of an increased risk. However, data on the structural characteristics of transformers is potentially useful for evaluating exposure-response relationship.

  12. High-k 3D-barium titanate foam/phenolphthalein poly(ether sulfone)/cyanate ester composites with frequency-stable dielectric properties and extremely low dielectric loss under reduced concentration of ceramics

    Science.gov (United States)

    Zheng, Longhui; Yuan, Li; Guan, Qingbao; Liang, Guozheng; Gu, Aijuan

    2018-01-01

    Higher dielectric constant, lower dielectric loss and better frequency stability have been the developing trends for high dielectric constant (high-k) materials. Herein, new composites have been developed through building unique structure by using hyperbranched polysiloxane modified 3D-barium titanate foam (BTF) (BTF@HSi) as the functional fillers and phenolphthalein poly(ether sulfone) (cPES)/cyanate ester (CE) blend as the resin matrix. For BTF@HSi/cPES/CE composite with 34.1 vol% BTF, its dielectric constant at 100 Hz is as high as 162 and dielectric loss is only 0.007; moreover, the dielectric properties of BTF@HSi/cPES/CE composites exhibit excellent frequency stability. To reveal the mechanism behind these attractive performances of BTF@HSi/cPES/CE composites, three kinds of composites (BTF/CE, BTF/cPES/CE, BTF@HSi/CE) were prepared, their structure and integrated performances were intensively investigated and compared with those of BTF@HSi/cPES/CE composites. Results show that the surface modification of BTF is good for preparing composites with improved thermal stability; while introducing flexible cPES to CE is beneficial to fabricate composites with good quality through effectively blocking cracks caused by the stress concentration, and then endowing the composites with good dielectric properties at reduced concentration of ceramics.

  13. Multiflash whistlers in ELF-band observed at low latitude

    Directory of Open Access Journals (Sweden)

    A. K. Singh

    2011-01-01

    Full Text Available Multiflash whistler-like event in the ELF-band, observed during March 1998 at low latitude station Jammu, is reported. The most prominent feature of these events is the multiflash nature along with the decrease in frequency within a very short span of time resembling similar to terrestrial whistlers. The events have a significantly smaller time duration (0.5–3.5 s than those reported earlier from high, mid and low latitudes and also display a diurnal maximum occurring around 09:30 h (IST. There have been similar reportings from other latitudes, but whistlers in the ELF-band with a multiflash nature along with a precursor emission have never been reported. Lightning seems to be the dominant source for the ELF whistlers reported here.

  14. On the significance of ELF basins

    Indian Academy of Sciences (India)

    Unknown

    to complement to chemical intuition (see, e.g., refs. 2, 3). In a mathematically more rigorous way, such regions, ELF basins,4 were defined following the spirit of Bader's Atoms in Molecules (AIM). All points in space which lead to the a given maximum of ELF, by following the gradient of ELF, belong to the same basin. Basins ...

  15. Effects of extremely low frequency electromagnetic fields on growth ...

    African Journals Online (AJOL)

    Electromagnetic fields are an important environmental factor that can influence the growth and development of plants. Exposure to EMFs was performed by a locally designed EMF generator. Our investigations were focused on plants grown from wet pretreated seeds with 3 and 10 mT for a 4 h exposure time and compared ...

  16. Extremely low frequency electromagnetic field in combination with ...

    African Journals Online (AJOL)

    Results: No significant alteration in the mRNA levels of NHEJ related genes was observed in ''β-Lap alone” and ''β-Lap + Mor” treated cells. The expression levels of NHEJ related genes were significantly increased in ''β-Lap + EMF” and ''β-Lap + Mor + EMF”. Multiple linear regression analysis showed that the effect of EMF ...

  17. Pmma fiber viscoelasticity in extremely low frequency regime

    DEFF Research Database (Denmark)

    Bundalo, Ivan-Lazar; Nielsen, Kristian; Bang, Ole

    2015-01-01

    . For a big duration of the strain with respect to relaxation, this fast relaxation wavelength range stays almost the same. However, with increasing relaxation duration and keeping the same strain duration, elastic relaxation wavelength range will be shortened for up to 18% (1%) when strained for 0.5% (1...

  18. Effects of extremely low frequency electromagnetic fields on growth ...

    African Journals Online (AJOL)

    Jane

    2011-08-22

    Aug 22, 2011 ... plants grown from exposed seeds to 3 mT intensity indicating that EMFs increases genetic ... (516 62, LEYBOLD, Germany) with a B-probe type of hall sound. Applied magnetic ..... *Significant from control at 0.05 level (t-test).

  19. Transcript profiling of Elf5+/- mammary glands during pregnancy identifies novel targets of Elf5.

    Directory of Open Access Journals (Sweden)

    Renee L Rogers

    Full Text Available BACKGROUND: Elf5, an epithelial specific Ets transcription factor, plays a crucial role in the pregnancy-associated development of the mouse mammary gland. Elf5(-/- embryos do not survive, however the Elf5(+/- mammary gland displays a severe pregnancy-associated developmental defect. While it is known that Elf5 is crucial for correct mammary development and lactation, the molecular mechanisms employed by Elf5 to exert its effects on the mammary gland are largely unknown. PRINCIPAL FINDINGS: Transcript profiling was used to investigate the transcriptional changes that occur as a result of Elf5 haploinsufficiency in the Elf5(+/- mouse model. We show that the development of the mouse Elf5(+/- mammary gland is delayed at a transcriptional and morphological level, due to the delayed increase in Elf5 protein in these glands. We also identify a number of potential Elf5 target genes, including Mucin 4, whose expression, is directly regulated by the binding of Elf5 to an Ets binding site within its promoter. CONCLUSION: We identify novel transcriptional targets of Elf5 and show that Muc4 is a direct target of Elf5, further elucidating the mechanisms through which Elf5 regulates proliferation and differentiation in the mammary gland.

  20. Amplitude variations of ELF radio waves in the Earth-ionosphere cavity with the day-night non-uniformity

    Science.gov (United States)

    Galuk, Yu P.; Nickolaenko, A. P.; Hayakawa, M.

    2018-04-01

    The real structure of lower ionosphere should be taken into account when modeling the sub-ionospheric radio propagation in the extremely low frequency (ELF) band and studying the global electromagnetic (Schumann) resonance of the Earth-ionosphere cavity. In the present work we use the 2D (two dimensional) telegraph equations (2DTE) for evaluating the effect of the ionosphere day-night non-uniformity on the electromagnetic field amplitude at the Schumann resonance and higher frequencies. Properties of the cavity upper boundary were taken into account by the full wave solution technique for realistic vertical profiles of atmosphere conductivity in the ambient day and ambient night conditions. We solved the electromagnetic problem in a cavity with the day-night non-uniformity by using the 2DTE technique. Initially, the testing of the 2DTE solution was performed in the model of the sharp day-night interface. The further computations were carried out in the model of the smooth day-night transition. The major attention was directed to the effects at propagation paths "perpendicular" or "parallel" to the solar terminator line. Data were computed for a series of frequencies, the comparison of the results was made and interpretation was given to the observed effects.

  1. Low frequency electric and magnetic fields

    Science.gov (United States)

    Spaniol, Craig

    1989-01-01

    Following preliminary investigations of the low frequency electric and magnetic fields that may exists in the Earth-ionospheric cavity, measurements were taken with state-of-the art spectrum analyzers. As a follow up to this activity, an investigation was initiated to determine sources and values for possible low frequency signal that would appear in the cavity. The lowest cavity resonance is estimated at about 8 Hz, but lower frequencies may be an important component of our electromagnetic environment. The potential field frequencies produced by the electron were investigated by a classical model that included possible cross coupling of the electric and gravitation fields. During this work, an interesting relationship was found that related the high frequency charge field with the extremely low frequency of the gravitation field. The results of numerical calculations were surprisingly accurate and this area of investigation is continuing. The work toward continued development of a standardized monitoring facility is continuing with the potential of installing the prototype at West Virginia State College early in 1990. This installation would be capable of real time monitoring of ELF signals in the Earth-ionoshpere cavity and would provide some directional information. A high gain, low noise, 1/f frequency corrected preamplifier was designed and tested for the ferrite core magnetic sensor. The potential application of a super conducting sensor for the ELF magnetic field detection is under investigation. It is hoped that a fully operational monitoring network could pinpoint the location of ELF signal sources and provide new information on where these signals originate and what causes them, assuming that they are natural in origin.

  2. Localized Elf Propagation Anomalies.

    Science.gov (United States)

    1985-06-01

    the above three SPEs. Those important auxiliary data are used as inputs to air- chemistry codes to calculate the electron and ion density height...horizontal magnetic intensity H is H A ( ATAR ) 1 / 2 (9 d)- 1/2 exp(-’afL- d) e- d/ 8 " 7 coso A/m, (1) where A depends on the antenna moment, frequency...those rates are input to air- chemistry equations to obtain height profiles of electron and ion densities. Calculation of ion-pair production rates

  3. Extremely Low-Metallicity Stars in the Classical Dwarf Galaxies

    NARCIS (Netherlands)

    Starkenburg, E.; DART Team, [Unknown; Aoki, W; Ishigaki, M; Suda, T; Tsujimoto, T; Arimoto, N

    After careful re-analysis of Ca II triplet calibration at low-metallicity, the classical satellites around the Milky Way are found not to be devoided of extremely low-metallicity stars and their (extremely) metal-poor tails are predicted to be much more in agreement with the Milky Way halo. A first

  4. Survival of extremely low-birth-weight infants

    African Journals Online (AJOL)

    Survival of extremely low-birth-weight (ELBW) infants in a resource-limited public hospital setting is still low in South. Africa. is study aimed ... Mortality as a result of prematurity is the major contributor to .... reported from a large cohort study that.

  5. Elf measurements in Greece conducted by the Greek Atomic Energy Commission

    International Nuclear Information System (INIS)

    Karabetsos, E.; Filippopoulos, G.; Koutounidis, D.; Govari, Ch.; Skamnakis, N.

    2006-01-01

    The Greek Atomic Energy Commission (E.E.A.E.) is the competent national authority for the protection of the general public and the environment from artificially produced non-ionizing radiation. To this end, E.E.A.E. carries out measurements in the vicinity of all kinds of facilities emitting E.L.F. electric and magnetic fields (e.g. power lines, high voltage substations) and RF electromagnetic fields (e.g. audio, radio and television antennas, mobile phone base stations, radar and satellite earth stations and other microwave communication systems), in order to monitor whether the general public exposure limits are being adhered to. Regarding the electromagnetic fields emitted by antenna stations, the safety limits in Greek legislation were recently set to 70% of the I.C.N.I.R.P. values and to 60% of them if the antenna station is closer than 300 m from the perimeter of day nurseries, schools, hospitals or elder-care facilities, while in the case of extremely low frequency fields, the limit values are set exactly the same as the reference levels in I.C.N.I.R.P. guidelines. Regarding the levels of E.L.F. electric and magnetic fields in Greece E.E.A.E. has conducted many measurements around the elements of the electric grid where the main interest of the public is focused. Theoretical estimations and typical values based on actual measurements of the fields in the vicinity of the power lines used in Greece are presented. Measurement results in the vicinity of substations are also presented. In general, the levels of the magnetic field in the vicinity of the power grid elements are well below the established safety limits; whereas the levels of the electric field may reach values comparable to the safety limits very close to extremely high voltage lines. However, there is no case where the measured values of elf electric or magnetic fields were higher than the safety limits. There are a few exceptional cases where measurements of RF fields conducted by E.E.A.E. in the

  6. Elf measurements in Greece conducted by the Greek Atomic Energy Commission

    Energy Technology Data Exchange (ETDEWEB)

    Karabetsos, E.; Filippopoulos, G.; Koutounidis, D.; Govari, Ch.; Skamnakis, N. [Greek Atomic Energy Commission, Non Ionizing Radiation Office, (Greece)

    2006-07-01

    The Greek Atomic Energy Commission (E.E.A.E.) is the competent national authority for the protection of the general public and the environment from artificially produced non-ionizing radiation. To this end, E.E.A.E. carries out measurements in the vicinity of all kinds of facilities emitting E.L.F. electric and magnetic fields (e.g. power lines, high voltage substations) and RF electromagnetic fields (e.g. audio, radio and television antennas, mobile phone base stations, radar and satellite earth stations and other microwave communication systems), in order to monitor whether the general public exposure limits are being adhered to. Regarding the electromagnetic fields emitted by antenna stations, the safety limits in Greek legislation were recently set to 70% of the I.C.N.I.R.P. values and to 60% of them if the antenna station is closer than 300 m from the perimeter of day nurseries, schools, hospitals or elder-care facilities, while in the case of extremely low frequency fields, the limit values are set exactly the same as the reference levels in I.C.N.I.R.P. guidelines. Regarding the levels of E.L.F. electric and magnetic fields in Greece E.E.A.E. has conducted many measurements around the elements of the electric grid where the main interest of the public is focused. Theoretical estimations and typical values based on actual measurements of the fields in the vicinity of the power lines used in Greece are presented. Measurement results in the vicinity of substations are also presented. In general, the levels of the magnetic field in the vicinity of the power grid elements are well below the established safety limits; whereas the levels of the electric field may reach values comparable to the safety limits very close to extremely high voltage lines. However, there is no case where the measured values of elf electric or magnetic fields were higher than the safety limits. There are a few exceptional cases where measurements of RF fields conducted by E.E.A.E. in the

  7. Particle motion in the ELF wiggler

    International Nuclear Information System (INIS)

    Wurtele, J.S.; Sessler, A.M.

    1982-06-01

    Particle motion in the ELF wiggler was investigated numerically and analytically. A transport system was designed using continuous quadrupole focusing in the wiggle plane and natural wiggle focusing in the non-wiggle plane

  8. Neonatal bartter syndrome in an extremely low birth weight baby

    Directory of Open Access Journals (Sweden)

    Deeparaj Hegde

    2017-01-01

    Full Text Available Early diagnosis of Bartter syndrome (BS in the neonatal period is a clinical challenge, more so in an extremely low birth weight (ELBW baby because of the inherent renal immaturity and the associated difficulty in fluid management. However, once a diagnosis is made, the disorder is known to respond well to fluid and electrolyte management, prostaglandin inhibitors, and potassium-sparing diuretics. Herein, we report a case of neonatal BS in a very premature ELBW infant.

  9. Analysis of impulse signals with Hylaty ELF station

    Science.gov (United States)

    Kulak, A.; Mlynarczyk, J.; Ostrowski, M.; Kubisz, J.; Michalec, A.

    2012-04-01

    Lighting discharges generate electromagnetic field pulses that propagate in the Earth-ionosphere waveguide. The attenuation in the ELF range is so small that the pulses originating from strong atmospheric discharges can be observed even several thousand kilometers away from the individual discharge. The recorded waveform depends on the discharge process, the Earth-ionosphere waveguide properties on the source-receiver path, and the transfer function of the receiver. If the distance from the source is known, an inverse method can be used for reconstructing the current moment waveform and the charge moment of the discharge. In order to reconstruct the source parameters from the recorded signal a reliable model of the radio wave propagation in the Earth-ionosphere waveguide as well as practical signal processing techniques are necessary. We present two methods, both based on analytical formulas. The first method allows for fast calculation of the charge moment of relatively short atmospheric discharges. It is based on peak amplitude measurement of the recorded magnetic component of the ELF EM field and it takes into account the receiver characteristics. The second method, called "inverse channel method" allows reconstructing the complete current moment waveform of strong atmospheric discharges that exhibit the continuing current phase, such as Gigantic Jets and Sprites. The method makes it possible to fully remove from the observed waveform the distortions related to the receiver's impulse response as well as the influence of the Earth-ionosphere propagation channel. Our ELF station is equipped with two magnetic antennas for Bx and By components measurement in the 0.03 to 55 Hz frequency range. ELF Data recording is carried out since 1993, with continuous data acquisition since 2005. The station features low noise level and precise timing. It is battery powered and located in the sparsely populated area, far from major electric power lines, which results in high

  10. Extreme low-power mixed signal IC design

    CERN Document Server

    Tajalli, Armin

    2010-01-01

    This book describes a completely novel class of techniques for designing ultra-low-power integrated circuits (ICs). In many applications such as battery operated systems and battery-less (energy-scavenging) systems, power dissipation is a critical parameter. As a result, there is a growing demand for reducing the power (energy) consumption in ICs to extremely low levels, not achievable by using classical ""subthreshold CMOS"" techniques. This book introduces a new family of ""subthreshold circuits"" called ""source-coupled circuits"". This family of circuits can be used for implementing digita

  11. Propagation of SLF/ELF electromagnetic waves

    CERN Document Server

    Pan, Weiyan

    2014-01-01

    This book deals with the SLF/ELF wave propagation, an important branch of electromagnetic theory. The SLF/ELF wave propagation theory is well applied in earthquake electromagnetic radiation, submarine communication, thunderstorm detection, and geophysical prospecting and diagnostics. The propagation of SLF/ELF electromagnetic waves is introduced in various media like the earth-ionospheric waveguide, ionospheric plasma, sea water, earth, and the boundary between two different media or the stratified media. Applications in the earthquake electromagnetic radiation and the submarine communications are also addressed. This book is intended for scientists and engineers in the fields of radio propagation and EM theory and applications. Prof. Pan is a professor at China Research Institute of Radiowave Propagation in Qingdao (China). Dr. Li is a professor at Zhejiang University in Hangzhou (China).

  12. TOTAL FINA ELF. Annual report 2002

    International Nuclear Information System (INIS)

    2003-01-01

    This document is the annual report 2002 of Total-Fina-Elf society, great company on the hydrocarbons market. According to the company objective (set the standard not only with the financial performance, but also with stringent requirements in terms of social and environmental responsibility), it presents the Chairman message, the corporate governance, the social and environmental responsibility, the future of energy, the human resources policy, the investor relations, the overview of Total-Fina-Elf fiscal year with financial information and 2002 industrial events. (A.L.B.)

  13. Fuzzy logic based ELF magnetic field estimation in substations

    International Nuclear Information System (INIS)

    Kosalay, I.

    2008-01-01

    This paper examines estimation of the extremely low frequency magnetic fields (MF) in the power substation. First, the results of the previous relevant research studies and the MF measurements in a sample power substation are presented. Then, a fuzzy logic model based on the geometric definitions in order to estimate the MF distribution is explained. Visual software, which has a three-dimensional screening unit, based on the fuzzy logic technique, has been developed. (authors)

  14. An active antenna for ELF magnetic fields

    Science.gov (United States)

    Sutton, John F.; Spaniol, Craig

    1994-01-01

    The work of Nikola Tesla, especially that directed toward world-wide electrical energy distribution via excitation of the earth-ionosphere cavity resonances, has stimulated interest in the study of these resonances. Not only are they important for their potential use in the transmission of intelligence and electrical power, they are important because they are an integral part of our natural environment. This paper describes the design of a sensitive, untuned, low noise active antenna which is uniquely suited to modern earth-ionosphere cavity resonance measurements employing fast-Fourier transform techniques for near-real-time data analysis. It capitalizes on a little known field-antenna interaction mechanism. Recently, the authors made preliminary measurements of the magnetic fields in the earth-ionosphere cavity. During the course of this study, the problem of designing an optimized ELF magnetic field sensor presented itself. The sensor would have to be small, light weight (for portable use), and capable of detecting the 5-50 Hz picoTesla-level signals generated by the natural excitations of the earth-ionosphere cavity resonances. A review of the literature revealed that past researchers had employed very large search coils, both tuned and untuned. Hill and Bostick, for example, used coils of 30,000 turns wound on high permeability cores of 1.83 m length, weighing 40 kg. Tuned coils are unsuitable for modern fast-Fourier transform data analysis techniques which require a broad spectrum input. 'Untuned' coils connected to high input impedance voltage amplifiers exhibit resonant responses at the resonant frequency determined by the coil inductance and the coil distributed winding capacitance. Also, considered as antennas, they have effective areas equal only to their geometrical areas.

  15. Extreme Low Light Requirement for Algae Growth Underneath Sea Ice

    DEFF Research Database (Denmark)

    Hancke, Kasper; Lund-Hansen, Lars C.; Lamare, Maxim L.

    2018-01-01

    Microalgae colonizing the underside of sea ice in spring are a key component of the Arctic foodweb as they drive early primary production and transport of carbon from the atmosphere to the ocean interior. Onset of the spring bloom of ice algae is typically limited by the availability of light......, and the current consensus is that a few tens-of-centimeters of snow is enough to prevent sufficient solar radiation to reach underneath the sea ice. We challenge this consensus, and investigated the onset and the light requirement of an ice algae spring bloom, and the importance of snow optical properties...... for light penetration. Colonization by ice algae began in May under >1 m of first-year sea ice with approximate to 1 m thick snow cover on top, in NE Greenland. The initial growth of ice algae began at extremely low irradiance (...

  16. [Extremely Low Birthweight Infants in Iceland. Health and development.].

    Science.gov (United States)

    Georgsdóttir, Ingibjœrg; Sæmundsen, Evald; Símonardóttir, Ingibjœrg; Halldórsson, Jónas G; Egilson, Snæfríður Thorn; Leósdóttir, Thornóra; Ingvarsdóttir, Brynhildur; Sindrason, Einar; Dagbjartsson, Atli

    2003-01-01

    Survival of extremely low birthweight infants (BWastma (p=0.001), convulsions (p=0.001), difficulties in swallowing (p=0.001) and weight gaining (p=0.005). At five years of age significantly more ELBW children born in 1991-95 compared to control children had abnormal general physical examination (p

  17. World map of ELF/VLF emissions as observed by a low-orbiting satellite

    International Nuclear Information System (INIS)

    Parrot, M.

    1990-01-01

    Statistical studies were performed of the intensities of the ELF/VLF emissions observed by the low-orbiting satellite AUREOL-3. Data were obtained from filterbanks and the frequency range of observations extends from a few tens of Hz up to 15 kHz. The most important phenomena observed are ELF hiss and VLF hiss. Electric and magnetic components are used. Thus, representation of the waves intensities in geographical coordinates was made at different frequencies. The relative ability of natural waves (whistler, hiss) and man-made waves, such as powerful VLF transmitters or powerline harmonic radiations (PLHR), to precipitate particles in the slot region, is studied. Using geomagnetical representation, it is shown that ELF hiss is maximum between 06 and 20 Magnetic Local Time and in the invariant latitude range 50 0 -70 0 as usual, but geographic representation indicates that the waves are intensified at the longitudes of VLF transmitters and near the South Atlantic Anomaly (SAA). The SAA plays a dominant role in the localization of the strongest ELF hiss. Weakest intensities are observed to the east of the SAA. As to the VLF hiss, the maximum intensity is related to regions of enhanced thunderstorm activity, and may be influenced by powerline harmonic radiations (PLHR) over USA. Comparisons with past work, experimental as well as theoretical, are made

  18. ELFE at DESY, status of machine studies

    Energy Technology Data Exchange (ETDEWEB)

    Tkatchenko, A.

    1996-12-31

    In this paper, the main outlines of the ELFE at DESY project are describes and the problems associated with the scenario proposed in july 1995 are reviewed. The results of the feasibility study recently carried out are presented and the achievable performances of the extracted beam in terms of emittance, energy spread and duty factor are given. (author).

  19. ELFE at DESY, status of machine studies

    International Nuclear Information System (INIS)

    Tkatchenko, A.

    1996-01-01

    In this paper, the main outlines of the ELFE at DESY project are describes and the problems associated with the scenario proposed in july 1995 are reviewed. The results of the feasibility study recently carried out are presented and the achievable performances of the extracted beam in terms of emittance, energy spread and duty factor are given. (author)

  20. On the efficiency of ELF/VLF generation using HF heating of the auroral electrojet

    International Nuclear Information System (INIS)

    Papadopoulos, K.; Milikh, G.M.; Wallace, T.; McCarrick, M.; Yang, X.

    2003-01-01

    Using experimental measurements and theoretical analysis, it is shown that the HF/ELF conversion efficiency is controlled by the timescale for electron temperature saturation. This is a function of the ERP and frequency of the heater and the ionospheric electron density profile. For the current HAARP parameters, this corresponds to frequencies between 2 and 4 kHz. Efficiency optimization techniques as applied to the projected upgrading of the HAARP heater to its design power of 3.6 MW are discussed

  1. Management and outcome of extremely low birth weight infants

    Directory of Open Access Journals (Sweden)

    Apostolos Papageorgiou

    2014-06-01

    Full Text Available Survival of extremely low birth weight (ELBW and extremely premature (EP infants has shown consistent improvement thanks to advances and innovations in perinatal and neonatal care. Regionalization, with high-risk deliveries in a tertiary perinatal center, offers the coordinated, collaborative, expert and specialized care needed by these mothers and their infants. Despite decreasing rates of the major neonatal morbidities observed in recent years, these continue still to be significant for ELBW/EP infants, impacting their overall prognosis. After NICU discharge and in the first years of life, issues with health, growth and development are common. In school age and adolescence, problems with behavior, socialization and cognition are prevalent. Adult outcomes of ELBW/EP need further clarity, emphasizing the importance for consistent long-term follow-up for this special cohort. Proceedings of the 10th International Workshop on Neonatology · Cagliari (Italy · October 22nd-25th, 2014 · The last ten years, the next ten years in Neonatology Guest Editors: Vassilios Fanos, Michele Mussap, Gavino Faa, Apostolos Papageorgiou

  2. Formation of Extremely Low-mass White Dwarf Binaries

    Science.gov (United States)

    Sun, M.; Arras, P.

    2018-05-01

    Motivated by the discovery of several pulsating, extremely low-mass white dwarfs (ELM WDs, mass M ≲ 0.18 M ⊙) that likely have WD companions, this paper discusses binary formation models for these systems. ELM WDs are formed using angular momentum losses by magnetic braking. Evolutionary models are constructed using the Modules for Experiments in Stellar Astrophysics (MESA), with ELM WD progenitors in the range 1.0 ≲ M d/M ⊙ ≲ 1.5 and WD companions in the range 0.4 ≲ M a/M ⊙ ≲ 0.9. A prescription to reduce magnetic braking for thin surface convection zones is included. Upon the thinning of the evolved donor envelope, the donor star shrinks out of contact and mass transfer (MT) ceases, revealing the ELM WD. Systems with low masses have previously been suggested as possible AM CVNs. Systems with high masses, up to the limit M ≃ 0.18 M ⊙ at which shell flashes occur on the WD cooling track, tend to expand out to orbital periods P orb ≳ 15 hr. In between this range, ELM WDs may become pulsators both as pre-WDs and on the WD cooling track. Brickhill’s criterion for convective mode driving is used to estimate the location of the blue edge of the g-mode instability strip. In the appendix, we show that the formation of an ELM WD by unstable MT or a common-envelope event is unlikely. Stable Roche-lobe overflow with conservative MT produces only M ≳ 0.2 M ⊙.

  3. Extremely Low Genomic Diversity of Rickettsia japonica Distributed in Japan.

    Science.gov (United States)

    Akter, Arzuba; Ooka, Tadasuke; Gotoh, Yasuhiro; Yamamoto, Seigo; Fujita, Hiromi; Terasoma, Fumio; Kida, Kouji; Taira, Masakatsu; Nakadouzono, Fumiko; Gokuden, Mutsuyo; Hirano, Manabu; Miyashiro, Mamoru; Inari, Kouichi; Shimazu, Yukie; Tabara, Kenji; Toyoda, Atsushi; Yoshimura, Dai; Itoh, Takehiko; Kitano, Tomokazu; Sato, Mitsuhiko P; Katsura, Keisuke; Mondal, Shakhinur Islam; Ogura, Yoshitoshi; Ando, Shuji; Hayashi, Tetsuya

    2017-01-01

    Rickettsiae are obligate intracellular bacteria that have small genomes as a result of reductive evolution. Many Rickettsia species of the spotted fever group (SFG) cause tick-borne diseases known as "spotted fevers". The life cycle of SFG rickettsiae is closely associated with that of the tick, which is generally thought to act as a bacterial vector and reservoir that maintains the bacterium through transstadial and transovarial transmission. Each SFG member is thought to have adapted to a specific tick species, thus restricting the bacterial distribution to a relatively limited geographic region. These unique features of SFG rickettsiae allow investigation of how the genomes of such biologically and ecologically specialized bacteria evolve after genome reduction and the types of population structures that are generated. Here, we performed a nationwide, high-resolution phylogenetic analysis of Rickettsia japonica, an etiological agent of Japanese spotted fever that is distributed in Japan and Korea. The comparison of complete or nearly complete sequences obtained from 31 R. japonica strains isolated from various sources in Japan over the past 30 years demonstrated an extremely low level of genomic diversity. In particular, only 34 single nucleotide polymorphisms were identified among the 27 strains of the major lineage containing all clinical isolates and tick isolates from the three tick species. Our data provide novel insights into the biology and genome evolution of R. japonica, including the possibilities of recent clonal expansion and a long generation time in nature due to the long dormant phase associated with tick life cycles. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  4. Influence of extreme low temperature conditions on the dynamic mechanical properties of carbon fiber reinforced polymers

    Science.gov (United States)

    Zaoutsos, S. P.; Zilidou, M. C.

    2017-12-01

    In the current study dynamic mechanical analysis (DMA) is performed in CFRPs that have been exposed for certain periods of time to extreme low temperatures. Through experimental data arising from respective DMA tests the influence of low temperature exposure (-40 °C) on the dynamic mechanical properties is studied. DMA tests were conducted in CFRP specimens in three point bending mode at both frequency and thermal scans in order to determine the viscoelastic response of the material in low temperatures. All experimental tests were run both for aged and pristine materials for comparison purposes. The results occurred reveal that there is deterioration both on transition temperature (Tg) and storage modulus values while there is also a moderate increase in the damping ability of the tested material as expressed by the factor tanδ as the period of exposure to low temperature increases.

  5. LPG in the Totalfina-Elf merger; Le GPL dans la fusion Totalfina-Elf

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2000-04-01

    Elf Aquitaine's take-over by TotalFina was approved on February 9, by the European Commission, with substantial changes to the project initially submitted. One of the main changes involves the sale of Elf Antargaz and of a part of Elf's associated LPG logistics. Rumors say that a dozen of potential buyers were on the ranks in February to acquire this company which is the second French LPG marketer. The sale seems to question the LPG scheme set by TotalFina at the end of 1999. We published in our previous issue this scheme which was designed to give a larger span to the product, with its own management apart from other specialties. (authors)

  6. A model explaining synchronization of neuron bioelectric frequency under weak alternating low frequency magnetic field

    International Nuclear Information System (INIS)

    Moral, A. del; Azanza, María J.

    2015-01-01

    A biomagnetic-electrical model is presented that explains rather well the experimentally observed synchronization of the bioelectric potential firing rate (“frequency”), f, of single unit neurons of Helix aspersa mollusc under the application of extremely low frequency (ELF) weak alternating (AC) magnetic fields (MF). The proposed model incorporates to our widely experimentally tested model of superdiamagnetism (SD) and Ca 2+ Coulomb explosion (CE) from lipid (LP) bilayer membrane (SD–CE model), the electrical quadrupolar long range interaction between the bilayer LP membranes of synchronized neuron pairs, not considered before. The quadrupolar interaction is capable of explaining well the observed synchronization. Actual extension of our SD–CE-model shows that the neuron firing frequency field, B, dependence becomes not modified, but the bioelectric frequency is decreased and its spontaneous temperature, T, dependence is modified. A comparison of the model with synchronization experimental results of pair of neurons under weak (B 0 ≅0.2–15 mT) AC-MF of frequency f M =50 Hz is reported. From the deduced size of synchronized LP clusters under B, is suggested the formation of small neuron networks via the membrane lipid correlation. - Highlights: • Neuron pair synchronization under low frequency alternating (AC) magnetic field (MF). • Superdiamagnetism and Ca 2+ Coulomb explosion for AC MF effect in synchronized frequency. • Membrane lipid electrical quadrupolar pair interaction as synchronization mechamism. • Good agreement of model with electrophysiological experiments on mollusc Helix neurons

  7. A model explaining synchronization of neuron bioelectric frequency under weak alternating low frequency magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Moral, A. del, E-mail: delmoral@unizar.es [Laboratorio de Magnetismo, Departamento de Física de Materia Condensada and Instituto de Ciencia de Materiales, Universidad de Zaragoza and Consejo Superior de Investigaciones Científicas, 50009 Zaragoza (Spain); Laboratorio de Magnetobiología, Departamento de Anatomía e Histología, Facultad de Medicina, Universidad de Zaragoza, 50009 Zaragoza (Spain); Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, 28223 Madrid (Spain); Azanza, María J., E-mail: mjazanza@unizar.es [Laboratorio de Magnetobiología, Departamento de Anatomía e Histología, Facultad de Medicina, Universidad de Zaragoza, 50009 Zaragoza (Spain); Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, 28223 Madrid (Spain)

    2015-03-01

    A biomagnetic-electrical model is presented that explains rather well the experimentally observed synchronization of the bioelectric potential firing rate (“frequency”), f, of single unit neurons of Helix aspersa mollusc under the application of extremely low frequency (ELF) weak alternating (AC) magnetic fields (MF). The proposed model incorporates to our widely experimentally tested model of superdiamagnetism (SD) and Ca{sup 2+} Coulomb explosion (CE) from lipid (LP) bilayer membrane (SD–CE model), the electrical quadrupolar long range interaction between the bilayer LP membranes of synchronized neuron pairs, not considered before. The quadrupolar interaction is capable of explaining well the observed synchronization. Actual extension of our SD–CE-model shows that the neuron firing frequency field, B, dependence becomes not modified, but the bioelectric frequency is decreased and its spontaneous temperature, T, dependence is modified. A comparison of the model with synchronization experimental results of pair of neurons under weak (B{sub 0}≅0.2–15 mT) AC-MF of frequency f{sub M}=50 Hz is reported. From the deduced size of synchronized LP clusters under B, is suggested the formation of small neuron networks via the membrane lipid correlation. - Highlights: • Neuron pair synchronization under low frequency alternating (AC) magnetic field (MF). • Superdiamagnetism and Ca{sup 2+} Coulomb explosion for AC MF effect in synchronized frequency. • Membrane lipid electrical quadrupolar pair interaction as synchronization mechamism. • Good agreement of model with electrophysiological experiments on mollusc Helix neurons.

  8. Expressing Disagreement in ELF Business Negotiations: Theory and Practice

    Science.gov (United States)

    Bjorge, Anne Kari

    2012-01-01

    English spoken by those who do not share their first language is increasingly referred to as English lingua franca (ELF). For ELF speakers, it can be a challenge to express conflicting opinions, as a common language and/or cultural background cannot be taken for granted. This is recognized by writers of business English textbooks, who provide…

  9. TotalFinaElf Factbook 2002

    International Nuclear Information System (INIS)

    2002-01-01

    This report presents the activities and results of the Group Total-Fina-Elf for the year 2002. It brings information and economic data on the following topics: the corporate and business; the upstream activities with the reserves, the costs, standardized measure and changes of discounted future net cash flow,oil and gas acreage, drilling, liquefied natural gas, pipelines; downstream activities with refining and marketing maps, refinery, petroleum products, sales, retail gasoline outlets; chemicals with sales and operating income by sector, major applications, base chemicals and polymers, intermediates and performance polymers. (A.L.B.)

  10. The ocean depths: Elf's target for 1997

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    Elf has long since been aware of the potential of sedimentary basins in the ocean depths. For this reason, the group has been preparing to descend to these depths for many years. Today, it is setting itself the target of being ready to optimise as from 1997 a discovery made in the depth between 400 and 1500 m of water in Africa. In the Gulf of Guinea, most of the neighbouring countries have opened up their deep sea offshore areas, in order to try to renew their reserves on the verge of the third millennium. Indeed a great similarity can be seen between the West African and the Brazilian ocean depths. In the African offshore areas, Elf has acquired or renewed eight blocks, four of which are in Nigeria, one in the Congo, one in Gabon and two in Angola. The group is also interested in the ocean depths which are now accessible in the North Sea, whether in the Norwegian (Voring and More) of British (Western Shetlands) areas. (author). 1 fig

  11. Is there ELF in ELT coursebooks?

    Directory of Open Access Journals (Sweden)

    Paola Vettorel

    2013-10-01

    Full Text Available This article aims to explore whether well-attested findings in the fields of World Englishes (WE and of English as a lingua franca (ELF have determined a shift in perspective in the overall approach to English language teaching (ELT, and how far this shift has permeated teaching materials and coursebooks. The research study was carried out in Italy, a country where ELT coursebooks have often played a relevant role in introducing innovations in language teaching methodology. The research design included a corpus of ten coursebooks that have been published and adopted in Italian secondary schools in the last 6 years. The coursebooks were evaluated in terms of the presence or absence of references to WE and/or ELF, of awareness-raising activities, of the promotion of using English outside the school environment and of the use of effective English communication and intercultural strategies among nonnative speakers. Findings show that there have been no significant changes in the inclusion of WE- and ELForiented materials and related tasks, apart from the area of promotion of cultural and intercultural awareness.

  12. Extremely Low Loss THz Guidance Using Kagome Lattice Porous Core Photonic Crystal Fiber

    DEFF Research Database (Denmark)

    Hossain, Anwar; Hasanuzzaman, G.K.M.; Habib, Selim

    2015-01-01

    A novel porous core Kagome lattice photonic crystal fiber is proposed for extremely low loss THz waves guiding. It has been reported that 82.5% of bulk effective material loss of Topas can be reduced...

  13. Dosimetry considerations in the head and retina for extremely low frequency electric fields

    International Nuclear Information System (INIS)

    Taki, M.; Suzuki, Y.; Wake, K.

    2003-01-01

    Magnetophosphenes are investigated from the viewpoint of electromagnetic dosimetry. Induced current density and internal electric fields at the threshold of perception are estimated by analytical and numerical calculations, assuming different models. Dosimetry for electrophoshenes is also discussed and compared with that for magnetophosphenes. The distribution of current density and internal electric fields is consistent with the experimental observation that flashing sensations reach their greatest intensity at the periphery of the visual field, for both electro and magnetophosphenes. The estimated thresholds in internal electric fields are consistent for magnetophosphenes and for electrophosphenes, respectively. The magnitudes of the thresholds, however, differ by about 10-fold. The thresholds in induced current density are critically dependent on the conductivity of the eye assumed for the calculations. The effect of thin membrane structure is also discussed with regard to the difference between electric field and magnetic field exposures. (author)

  14. The effect of extreme-low-frequency electromagnetic field on air ...

    African Journals Online (AJOL)

    Electromagnetic fields produce alternating electric fields and modify static electric fields in the vicinity. These electric fields, if large enough, can alter the concentration or transport of airborne particles (including particles harmful to health). In this study, the concentration of radioactive materials (gamma radiation) was ...

  15. Characterization of exposure to extremely low frequency magnetic fields using multidimensional analysis techniques.

    Science.gov (United States)

    Verrier, A; Souques, M; Wallet, F

    2005-05-01

    Our lack of knowledge about the biological mechanisms of 50 Hz magnetic fields makes it hard to improve exposure assessment. To provide better information about these exposure measures, we use multidimensional analysis techniques to examine the relations between different exposure metrics for a group of subjects. We used a combination of a two stage Principal Component Analysis (PCA) followed by an ascending hierarchical classification (AHC) to identify a set of measures that would capture the characteristics of the total exposure. This analysis gives an indication of the aspects of the exposure that are important to capture to get a complete picture of the magnetic field environment. We calculated 44 metrics of exposure measures from 16 exposed EDF employees and 15 control subjects, containing approximately 20,000 recordings of magnetic field measurements, taken every 30 s for 7 days with an EMDEX II dosimeter. These metrics included parameters used routinely or occasionally and some that were new. To eliminate those that expressed the least variability and that were most highly correlated to one another, we began with an initial Principal Component Analysis (PCA). A second PCA of the remaining 12 metrics enabled us to identify from the foreground 82.7% of the variance: the first component (62.0%) was characterized by central tendency metrics, and the second (20.7%) by dispersion characteristics. We were able to use AHC to divide the entire sample (of individuals) into four groups according to the axes that emerged from the PCA. Finally, discriminant analysis tested the discriminant power of the variables in the exposed/control classification as well as those from the AHC classification. The first showed that two subjects had been incorrectly classified, while no classification error was observed in the second. This exploratory study underscores the need to improve exposure measures by using at least two dimensions: intensity and dispersion. It also indicates the usefulness of constructing a typology of magnetic field exposures. Copyright 2005 Wiley-Liss, Inc.

  16. Extremely low frequency electromagnetic field in combination with β ...

    African Journals Online (AJOL)

    Fatemeh Sanie-Jahromi

    Results: No significant alteration in the mRNA levels of NHEJ related genes was observed in ''b-Lap alone” and ''b-Lap + Mor” treated cells. The expression levels of NHEJ related genes were significantly increased in ''b-Lap + EMF” and ''b-Lap + Mor + EMF”. Multiple linear regression analysis showed that the effect of.

  17. Radiofrequency and extremely low-frequency electromagnetic field effects on the blood-brain barrier.

    Science.gov (United States)

    Nittby, Henrietta; Grafström, Gustav; Eberhardt, Jacob L; Malmgren, Lars; Brun, Arne; Persson, Bertil R R; Salford, Leif G

    2008-01-01

    During the last century, mankind has introduced electricity and during the very last decades, the microwaves of the modern communication society have spread a totally new entity--the radiofrequency fields--around the world. How does this affect biology on Earth? The mammalian brain is protected by the blood-brain barrier, which prevents harmful substances from reaching the brain tissue. There is evidence that exposure to electromagnetic fields at non thermal levels disrupts this barrier. In this review, the scientific findings in this field are presented. The result is a complex picture, where some studies show effects on the blood-brain barrier, whereas others do not. Possible mechanisms for the interactions between electromagnetic fields and the living organisms are discussed. Demonstrated effects on the blood-brain barrier, as well as a series of other effects upon biology, have caused societal anxiety. Continued research is needed to come to an understanding of how these possible effects can be neutralized, or at least reduced. Furthermore, it should be kept in mind that proven effects on biology also should have positive potentials, e.g., for medical use.

  18. Electrochemical Evaluation of Extremely-Low Frequency Magnetic Field Effects on Sulphate-Reducing Bacteria

    Czech Academy of Sciences Publication Activity Database

    Fojt, Lukáš; Vetterl, Vladimír

    2012-01-01

    Roč. 58, č. 1 (2012), s. 44-48 ISSN 0015-5500 R&D Projects: GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Institutional support: RVO:68081707 Keywords : RAT-BRAIN CELLS * HZ ELECTROMAGNETIC-FIELDS * STRAND DNA BREAKS Subject RIV: BO - Biophysics Impact factor: 1.219, year: 2012

  19. The Effect of Extremely Low Frequency Radiation on Human Performance: A Preliminary Study.

    Science.gov (United States)

    1974-08-01

    Medical Research Laboratory Prepared for: Bu,’eau of Medicine and Surgery August 1974 DISTRIBUTED BY: HIM National Technical Information Service U. S... NATIONAL TECHNICAL INFORMATION SERVICE US Nptdrslmr,iI .1 C.-In~oce SSpiiISIiold, VA. 72151 PRICES SUBJECI" TO CHARGE FORM IA7 (P’AGE I Unclassified701 DD...anecdotal evidence which attributes a rather ambiguously defined neurasthenic syndrome (general weakness, f,9tigue, laziness, sleepiness in daytime, etc

  20. Effects of extremely low frequency electromagnetic fields on liver enzymes in Guinea pig

    International Nuclear Information System (INIS)

    Zare, S.; Hayatgeiby, H.; Alivandy Farkhad, S.; Tagizadeh, A.

    2007-01-01

    Electromagnetic field has various effects on living organisms such as blood composition or enzymatic changes. The effects depend on the electromagnetic intensity and the time of exposure. This study has been carried out to measure the variations of liver enzymes SGOT and SGPT Levels in 36 adult male, Guinea Pigs, that have been divided into 6 groups. Group A, as the control, exposed to nil electromagnetic field for two hours per day for 5 days. Group B, exposed to 0.013 micro T in 5 Hz for the same period. Group C, exposed to 0.207 micro T in 50 Hz in the similar condition. Group D, exposed for' four hours per day for 5 days in 0.013 micro T in 5Hz. Group E, tested in 0.207 micro T in 50 Hz as the group D. Group F, used as the controlled group exposed for four hours per day in nil electromagnetic field. Blood of the Guinea pigs were analysed after 5 days. The results have shown significant differences among different groups, regarding the SCOT and SGPT when compared with those of the controlled group. Statistically, they are meaningful when measured by Dunnett test indicating a significant difference between the controlled group and the tested group, soas the SGOT and SGPT have decreased in both cases

  1. Extremely low-frequency electromagnetic fields disrupt magnetic alignment of ruminants

    Czech Academy of Sciences Publication Activity Database

    Burda, H.; Begall, S.; Červený, Jaroslav; Neef, J.; Němec, P.

    2009-01-01

    Roč. 106, č. 14 (2009), s. 5708-5713 ISSN 0027-8424 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60930519 Keywords : cattle * magnetoreception * roe deer * power lines Subject RIV: EH - Ecology, Behaviour Impact factor: 9.432, year: 2009

  2. EVALUATING EXTREMELY LOW FREQUENCY MAGNETIC FIELDS IN THE REAR SEATS OF THE ELECTRIC VEHICLES.

    Science.gov (United States)

    Lin, Jun; Lu, Meng; Wu, Tong; Yang, Lei; Wu, Tongning

    2018-03-23

    In the electric vehicles (EVs), children can sit on a safety seat installed in the rear seats. Owing to their smaller physical dimensions, their heads, generally, are closer to the underfloor electrical systems where the magnetic field (MF) exposure is the greatest. In this study, the magnetic flux density (B) was measured in the rear seats of 10 different EVs, for different driving sessions. We used the measurement results from different heights corresponding to the locations of the heads of an adult and an infant to calculate the induced electric field (E-field) strength using anatomical human models. The results revealed that measured B fields in the rear seats were far below the reference levels by the International Commission on Non-Ionizing Radiation Protection. Although small children may be exposed to higher MF strength, induced E-field strengths were much lower than that of adults due to their particular physical dimensions.

  3. Complex magnetic susceptibility setup for spectroscopy in the extremely low-frequency range

    NARCIS (Netherlands)

    Kuipers, B.W.M.; Bakelaar, I.A.; Klokkenburg, M.; Erne, B.H.

    2008-01-01

    A sensitive balanced differential transformer was built to measure complex initial parallel magnetic susceptibility spectra in the 0.01–1000 Hz range. The alternating magnetic field can be chosen sufficiently weak that the magnetic structure of the samples is only slightly perturbed and the low

  4. ELF-VLF communications through-the-Earth

    Science.gov (United States)

    Buettner, H. M.; Burke, G. J.; Didwall, E. M.; Holladay, G.; Lytle, R. J.

    1985-06-01

    We use computer models and experiments to explore the feasibility of communication between points underground and on the Earth's surface. Emphasis is placed on ELF-VLF electromagnetic propagation through the Earth; nominally, we investigated propagation in the 200 Hz-30 kHz frequency range. The computer modeling included calculations of the fields of a point electric or magnetic source in a homogeneous half space or a stratified Earth. Initial results for an insulated antenna of finite length are also considered. The experiments involved through-the-Earth transmissions at two locations in Pennsylvania, both of which had large formations of limestone. Initial results indicate that information rates as high as kbits/s may be possible for subsurface depths of 300 m or less. Accuracy of these estimates depends on the electromagnetic propagation constants of the rock, the noise characteristics, and modulation scheme. Although a nuisance for evaluating through-the-Earth propagation, the existence of subsurface metal conductors can improve the transmission character of the site.

  5. Indomethacin prophylaxis or expectant treatment of patent ductus arteriosus in extremely low birth weight infants?

    Science.gov (United States)

    Cordero, L; Nankervis, C A; Delooze, D; Giannone, P J

    2007-03-01

    Indomethacin prophylaxis or expectant treatment are common strategies for the prevention or management of symptomatic patent ductus arteriosus (sPDA). To compare the clinical responses of extremely low birth weight (ELBW) infants to indomethacin prophylaxis with that of other infants who were managed expectantly by being treated with indomethacin or surgically only after an sPDA was detected. Retrospective cohort investigation of 167 ELBW infants who received indomethacin prophylaxis (study) and 167 ELBW infants (control) treated expectantly who were matched by year of birth (1999 to 2006), birth weight, gestational age (GA) and gender. Mothers of the two groups of infants were comparable demographically and on the history of preterm labor, pre-eclampsia, antepartum steroids and cesarean delivery. Study and control infants were similar in birth weight, GA, low 5 min Apgar scores, surfactant administration, the need for arterial blood pressure control, bronchopulmonary dysplasia and neonatal mortality. Necrotizing enterocolitis, spontaneous intestinal perforations, intraventricular hemorrhage grade III to IV, periventricular leukomalacia and stage 3 to 5 retinopathy of prematurity occurred also with similar frequency in both groups of infants. In the indomethacin prophylaxis group, 29% of the infants developed sPDA, and of them 38% responded to indomethacin treatment. In the expectantly treated group, 37% developed sPDA, and of them 59% responded to indomethacin treatment. Overall, surgical ligation rate for sPDA was similar between both groups of patients. In our experience, indomethacin prophylaxis does not show any advantages over expectant early treatment on the management of sPDA in ELBW infants. Although no deleterious effects were observed, prophylaxis exposed a significant number of infants who may have never developed sPDA, to potential indomethacin-related complications.

  6. Screening for autism in preterm children with extremely low and very low birth weight

    Science.gov (United States)

    Dudova, Iva; Kasparova, Martina; Markova, Daniela; Zemankova, Jana; Beranova, Stepanka; Urbanek, Tomas; Hrdlicka, Michal

    2014-01-01

    Background Studies of children with very low birth weight (VLBW, 1,000–1,500 g) and extremely low birth weight (ELBW, less than 1,000 g) indicate that this population seems to be at increased risk of autism spectrum disorder (ASD). Methods Parents of 101 VLBW and ELBW children (age 2 years, corrected for prematurity) agreed to participate in the study and signed informed consents; however, parents of only 75 children (44 boys, 31 girls) completed the screening questionnaires. The screening battery included the Modified Checklist for Autism in Toddlers (M-CHAT), Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist (CSBS-DP-ITC), and the Infant/Toddler Sensory Profile (ITSP). Children with disabilities were excluded. All children who screened positive on any of the screening tools were subsequently invited for a detailed assessment. Results Thirty-two children (42.7%) screened positive on at least one of the screening questionnaires. The screening tool with the most positive results was the CSBS-DP-ITC (26 positive screens), followed by the M-CHAT (19 positive screens) and the ITSP (11 positive screens). Of the 32 children who tested positive, 19 participated in the detailed follow-up assessment. A diagnosis of ASD was confirmed in eight of the 19 children. ASD prevalence, calculated from those 19 children and those with negative screening results (43 children), yielded a prevalence of 12.9% in the sample. The difference in frequency of positive screens between the tests was significant (P=0.011). In pair comparisons, ITSP was found to be significantly less positive than CSBS-DP-ITC (P=0.032). No significant differences were found between the M-CHAT and CSBS-DP-ITC or between the M-CHAT and ITSP. Conclusion The results strongly support the hypothesis of an increased prevalence of autism in children with a birth weight less than 1,500 g. PMID:24627633

  7. Cohesion as interaction in ELF spoken discourse

    Directory of Open Access Journals (Sweden)

    T. Christiansen

    2013-10-01

    Full Text Available Hitherto, most research into cohesion has concentrated on texts (usually written only in standard Native Speaker English – e.g. Halliday and Hasan (1976. By contrast, following on the work in anaphora of such scholars as Reinhart (1983 and Cornish (1999, Christiansen (2011 describes cohesion as an interac­tive process focusing on the link between text cohesion and discourse coherence. Such a consideration of cohesion from the perspective of discourse (i.e. the process of which text is the product -- Widdowson 1984, p. 100 is especially relevant within a lingua franca context as the issue of different variations of ELF and inter-cultural concerns (Guido 2008 add extra dimensions to the complex multi-code interaction. In this case study, six extracts of transcripts (approximately 1000 words each, taken from the VOICE corpus (2011 of conference question and answer sessions (spoken interaction set in multicultural university con­texts are analysed in depth by means of a qualitative method.

  8. Incidence and outcomes of acute kidney injury in extremely-low-birth-weight infants.

    Directory of Open Access Journals (Sweden)

    Chien-Chung Lee

    Full Text Available Acute kidney injury (AKI is a common event in the neonatal intensive care unit (NICU, especially in extremely-low-birth-weight (ELBW infants. This cohort study investigated the incidence of and risk factors for AKI in ELBW infants and their overall survival at the postmenstrual age (PMA of 36 weeks.All ELBW infants admitted to our NICU between January 2010 and December 2013 were enrolled. Those who died prior to 72 hours of life, had congenital renal abnormality, or had only one datum of the serum creatinine (SCr level after the first 24 hours of life were excluded. The criteria used for the diagnosis of AKI was set according to the modified neonatal KDIGO AKI definition.AKI occurred in 56% of 276 infants. Specifically, stage 1, stage 2, and stage 3 AKI occurred in 30%, 17%, and 9% of ELBW infants, respectively. High-frequency ventilation support (adjusted odds ratio [OR]: 3.4, 95% confidence interval [CI]: 1.78-6.67, p< 0.001, the presence of patent ductus arteriosus (adjusted OR: 4.3, 95% CI: 2.25-8.07, p < 0.001, lower gestational age (adjusted OR for gestational age: 0.7, 95% CI: 0.58-0.83, < 0.001, and inotropic agent use (adjusted OR: 2.6, 95% CI: 1.31-5.21, p = 0.006 were independently associated with AKI. Maternal pre-eclampsia was a protective factor (adjusted OR: 0.4, 95% CI: 0.14-0.97, p = 0.044. Infants with AKI had higher mortality before the PMA of 36 weeks with an adjusted hazard ratio (HR of 5.34 (95% CI: 1.21-23.53, p = 0.027. Additionally, infants with stage 3 AKI had a highest HR of 10.60, 95% CI: 2.09-53.67, p = 0.004.AKI was a very common event (56% in ELBW infants and was associated with a lower GA, high-frequency ventilation support, the presence of PDA, and inotropic agent use. AKI reduced survival of ELBW infants before the PMA of 36 weeks.

  9. ELF4 Regulates GIGANTEA Chromatin Access through Subnuclear Sequestration

    Directory of Open Access Journals (Sweden)

    Yumi Kim

    2013-03-01

    Full Text Available Many organisms, including plants, use the circadian clock to measure the duration of day and night. Daily rhythms in the plant circadian system are generated by multiple interlocked transcriptional/translational loops and also by spatial regulations such as nuclear translocation. GIGANTEA (GI, one of the key clock components in Arabidopsis, makes distinctive nuclear bodies like other nuclear-localized circadian regulators. However, little is known about the dynamics or roles of GI subnuclear localization. Here, we characterize GI subnuclear compartmentalization and identify unexpected dynamic changes under diurnal conditions. We further identify EARLY FLOWERING 4 (ELF4 as a regulator of GI nuclear distribution through a physical interaction. ELF4 sequesters GI from the nucleoplasm, where GI binds the promoter of CONSTANS (CO, to discrete nuclear bodies. We suggest that the subnuclear compartmentalization of GI by ELF4 contributes to the regulation of photoperiodic flowering.

  10. Scrotal enteric fistula in an extremely low birth weight premature neonate

    Directory of Open Access Journals (Sweden)

    Caitlin A. Smith

    2018-03-01

    Full Text Available Congenital inguinal hernia is a common condition in the pediatric population. Incarceration of inguinal hernias is known to result in significant morbidity such as necrotic bowel, and if not recognized promptly, has the potential to present as a scrotal fecal fistula. We present an extremely low birth weight premature male infant who developed spontaneous fecal drainage from his right scrotum.

  11. Delivery of the extremely low-birth- weight vertex-presenting baby ...

    African Journals Online (AJOL)

    2010-12-02

    Dec 2, 2010 ... rise in the caesarean section rate.1 This rise has been disproportionate to ... a possible extremely low-birth-weight infant the risks of mortality and short- and .... the US Health Statistics data from 1999 to 2000 using multivariate ...

  12. General movements in the first fourteen days of life in extremely low birth weight (ELBW) infants

    NARCIS (Netherlands)

    de Vries, N. K. S.; Erwich, J. J. H. M.; Bos, A. F.

    2008-01-01

    Objective: To assess the quality of general movements (GMs) in the first fourteen days of life in relation to obstetric and postnatal risk factors and neurodevelopmental outcome in extremely low birth weight (ELBW) infants. Study design: The GMs of nineteen infants were assessed on days 2, 4, 6, 10

  13. Serum magnesium in the first week of life in extremely low birth weight infants.

    LENUS (Irish Health Repository)

    Noone, D

    2012-01-01

    Evidence that antenatal administration of magnesium sulfate (MgSO(4)) to women in preterm labor may confer fetal neuroprotection is growing. MgSO(4) crosses the placenta and can affect the neonate. Magnesium homeostasis in extremely low birth weight (ELBW) infants remains to be clarified.

  14. ELFE: New machine proposed for Europe

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    Understanding the dynamics of non-perturbative QCD (the physics of quark and gluon interactions at large coupling) is one of the most challenging problems of modern physics. The two phenomena of quark confinement, which binds quarks permanently inside hadrons, and the dynamical breaking of chiral symmetry, which gives us pion physics and more massive constituent quarks of low energy QCD, define the interface of nuclear and particle physics. The Electron Laboratory for Europe project - ELFE - is the European machine initiative proposed as the optimum experimental tool to study this ''Confinement Physics'', which is virgin territory for both particle and nuclear physicists. Until recently, lack of data in the confinement domain had led to slow theoretical progress in understanding the quark structure of nuclear and hadronic matter. This situation has improved considerably, with new discoveries in high energy deep inelastic scattering experiments together with important advances in large acceptance detector technology and continuous electron beams at low energies. At high energies, the CERN muon beam experiments in deep inelastic scattering (probing the remote interior of nucleons) opened an exciting new window on nucleon structure with the discovery of three unexpected effects: the EMC (European Muon Collaboration) nuclear and spin effects, and the observation of a surprisingly large difference between the the number of anti-up and anti-down quarks in nucleons. In 1983, the EMC nuclear effect showed that the quark structure of the free nucleon is modified in the nuclear environment. The EMC spin effect (or proton spin problem) is the discovery that it looks as though quark spin contributes only 22% of that of the nucleon (July 1994, page 19)

  15. On the observations of unique low latitude whistler-triggered VLF/ELF emissions

    Science.gov (United States)

    Altaf, M.; Singh, K. K.; Singh, A. K.; Lalmani

    A detailed analysis of the VLF/ELF wave data obtained during a whistler campaign under All India Coordinated Program of Ionosphere Thermosphere Studies (AICPITS) at our low latitude Indian ground station Jammu (geomag. lat. = 22° 26‧ N, L = 1.17) has yielded two types of unusual and unique whistler-triggered VLF/ELF emissions. These include (1) whistler-triggered hook emissions and (2) whistler-triggered long enduring discrete chorus riser emissions in VLF/ELF frequency range during night time. Such types of whistler-triggered emissions have not been reported earlier from any of the ground observations at low latitudes. In the present study, the observed characteristics of these emissions are described and interpreted. Dispersion analysis of these emissions show that the whistlers as well as emissions have propagated along a higher geomagnetic field line path with L-values lying ∼L = 4, suggesting that these triggered emissions are to be regarded as mid-latitude emissions. These waves could have propagated along the geomagnetic field lines either in a ducted mode or in a pro-longitudinal (PL) mode. The measured intensity of the triggered emissions is almost equal to that of the source waves and does not vary throughout the period of observation on that day. It is speculated that these emissions may have been generated through a process of resonant interaction of the whistler waves with energetic electrons. Parameters related to this interaction are computed for different values of L and wave amplitude. The proposed mechanism explains some aspects of the dynamic spectra.

  16. The anabolic activity of bone tissue, suppressed by disuse, is normalized by brief exposure to extremely low-magnitude mechanical stimuli

    Science.gov (United States)

    Rubin, C.; Xu, G.; Judex, S.

    2001-01-01

    It is generally believed that mechanical signals must be large in order to be anabolic to bone tissue. Recent evidence indicates, however, that extremely low-magnitude (bone formation if induced at a high frequency. We examined the ability of extremely low-magnitude, high-frequency mechanical signals to restore anabolic bone cell activity inhibited by disuse. Adult female rats were randomly assigned to six groups: baseline control, age-matched control, mechanically stimulated for 10 min/day, disuse (hind limb suspension), disuse interrupted by 10 min/day of weight bearing, and disuse interrupted by 10 min/day of mechanical stimulation. After a 28 day protocol, bone formation rates (BFR) in the proximal tibia of mechanically stimulated rats increased compared with age-matched control (+97%). Disuse alone reduced BFR (-92%), a suppression only slightly curbed when disuse was interrupted by 10 min of weight bearing (-61%). In contrast, disuse interrupted by 10 min per day of low-level mechanical intervention normalized BFR to values seen in age-matched controls. This work indicates that this noninvasive, extremely low-level stimulus may provide an effective biomechanical intervention for the bone loss that plagues long-term space flight, bed rest, or immobilization caused by paralysis.

  17. Screening for autism in preterm children with extremely low and very low birth weight

    Directory of Open Access Journals (Sweden)

    Dudova I

    2014-02-01

    Full Text Available Iva Dudova,1 Martina Kasparova,2 Daniela Markova,3 Jana Zemankova,4 Stepanka Beranova,1 Tomas Urbanek,5 Michal Hrdlicka1 1Department of Child Psychiatry, Charles University Second Faculty of Medicine and University Hospital Motol, Prague, Czech Republic; 2Department of Pediatrics, Charles University Second Faculty of Medicine and University Hospital Motol, Prague, Czech Republic; 3Department of Pediatrics and Adolescent Medicine, Charles University First Faculty of Medicine and General University Hospital, Prague, Czech Republic; 4Department of Pediatrics, Charles University Faculty of Medicine and University Hospital, Hradec Kralove, Czech Republic; 5Institute of Psychology, Academy of Sciences, Brno, Czech Republic Background: Studies of children with very low birth weight (VLBW, 1,000–1,500 g and extremely low birth weight (ELBW, less than 1,000 g indicate that this population seems to be at increased risk of autism spectrum disorder (ASD. Methods: Parents of 101 VLBW and ELBW children (age 2 years, corrected for prematurity agreed to participate in the study and signed informed consents; however, parents of only 75 children (44 boys, 31 girls completed the screening questionnaires. The screening battery included the Modified Checklist for Autism in Toddlers (M-CHAT, Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist (CSBS-DP-ITC, and the Infant/Toddler Sensory Profile (ITSP. Children with disabilities were excluded. All children who screened positive on any of the screening tools were subsequently invited for a detailed assessment. Results: Thirty-two children (42.7% screened positive on at least one of the screening questionnaires. The screening tool with the most positive results was the CSBS-DP-ITC (26 positive screens, followed by the M-CHAT (19 positive screens and the ITSP (11 positive screens. Of the 32 children who tested positive, 19 participated in the detailed follow-up assessment. A

  18. The Measurement of Low Frequency Magnetic Field of Two Kinds of GSM900 Mobile Phone

    Directory of Open Access Journals (Sweden)

    Mehri Kaviani Moghadam

    2008-06-01

    Full Text Available Introduction:  The  use  of  mobile  communication  systems  has  dramatically  increased  over  the  past  decade. Although many studies have been performed to determine the effect of radio frequency (RF but  less attention has been paid to the possible biological impact of exposure to extremely low frequency  (ELF components.   The objective of this study is two folds. One is to design the equipments needed for the measurement of  the ELF fields of two types of GSM900 mobile phone. Secondly, use a protocol suitable for an accurate  assessment of the ELF fields.  Materials  and Methods:  First  a  home-made  search  coil  was  provided  and  calibrated precisely  under  several experiments. Using Fast Fourier Transform, the power spectrum density of the induced voltage in  the search coil was analyzed and the amplitudes of 217 Hz and its harmonics were extracted and then the  distribution of magnetic field in the back side of mobile phones was determined.  Results: The values of B-field on the back side of the two kinds of GSM mobile phone were different.  They  were  between  50  to  160  µT in  Nokia  3310  and  14  to  30  µT in  Nokia  8310.  Considering  the  difference between the amplitudes of frequency components at 217 Hz and its harmonics in the two kinds  of mobile phone, a range of magnetic flux density at different times in a five day period was measured.  Discussion and Conclusion: These findings emphasize the need for considering the distribution of low  frequency magnetic field from mobile phone when biological effects of magnetic fields are studied. To  determine  the  intensity  windowing  effect,  one  must  consider  the  physical  characteristics  of  the  fundamental  frequency  component  wave  (217  Hz  and  its  harmonics  produced  by  the  mobile  phone  similar to the one generated under a real situation.

  19. Photon tagging; considerations for an ELFE DESY proposal

    International Nuclear Information System (INIS)

    Mackenzie, J.A.

    1996-01-01

    Photon Tagging in the 5-15 GeV region is considered. The advantage of performing exclusive measurements in relation to obtainable photon flux in described. Finally some technical problems in relation to implementing a photon beam in the framework of the ELFE at DESY proposal are discussed. (author)

  20. Conflict or Cooperation: The Use of Backchannelling in ELF Negotiations

    Science.gov (United States)

    Bjorge, Anne Kari

    2010-01-01

    The international business community relies heavily on English Lingua Franca (ELF) as a shared means of communication, and English business language programmes thus feature prominently within the field of English for Specific Purposes (ESP). Business ESP programmes, however, have little focus on active listening, which previous research has…

  1. Coffin-Siris syndrome: a case of an extremely low birthweight infant with severe kyphoscoliosis.

    Science.gov (United States)

    Suzumura, H; Sakurai, K; Kano, K; Ichimura, T

    1996-10-01

    A case of Coffin-Siris syndrome in a male of extremely low birthweight with severe kyphoscoliosis is reported. His birthweight was 965 g, the lowest reported in the world for an infant with this syndrome. Coffin-Siris syndrome is characterized by nail hypoplasia of the fingers and toes, eyebrow hypertrichosis, prominent lips and prenatal or postnatal growth retardation. He was the only case who was mechanically ventilated from birth because of birth asphyxia. He died at 12 days of age because of sepsis, a poor immune system as in other extremely low birthweight infants, and because he easily suffered from upper respiratory infection as a result of Coffin-Siris syndrome. Kyphoscoliosis is suggested as one of the important features in low birthweight cases of Coffin-Siris syndrome in previous reports and in the present case.

  2. Early Working Memory in Children Born With Extremely Low Birth Weight: Assessed by Object Permanence

    OpenAIRE

    Lowe, Jean; MacLean, Peggy C.; Shaffer, Michele L.; Watterberg, Kristi

    2009-01-01

    Object permanence is considered the earliest method for assessing working memory. Factors affecting object permanence performance in a sample of two hundred and thirty-three 18- to 22-month olds born with extremely low birth weight were examined. It was hypothesized that object permanence would be directly related to emotional and attention regulation, that children with lower birth weight and higher illness severity would have more difficulty on the object permanence task, and that no ethnic...

  3. Ensemble reconstruction of spatio-temporal extreme low-flow events in France since 1871

    Science.gov (United States)

    Caillouet, Laurie; Vidal, Jean-Philippe; Sauquet, Eric; Devers, Alexandre; Graff, Benjamin

    2017-06-01

    The length of streamflow observations is generally limited to the last 50 years even in data-rich countries like France. It therefore offers too small a sample of extreme low-flow events to properly explore the long-term evolution of their characteristics and associated impacts. To overcome this limit, this work first presents a daily 140-year ensemble reconstructed streamflow dataset for a reference network of near-natural catchments in France. This dataset, called SCOPE Hydro (Spatially COherent Probabilistic Extended Hydrological dataset), is based on (1) a probabilistic precipitation, temperature, and reference evapotranspiration downscaling of the Twentieth Century Reanalysis over France, called SCOPE Climate, and (2) continuous hydrological modelling using SCOPE Climate as forcings over the whole period. This work then introduces tools for defining spatio-temporal extreme low-flow events. Extreme low-flow events are first locally defined through the sequent peak algorithm using a novel combination of a fixed threshold and a daily variable threshold. A dedicated spatial matching procedure is then established to identify spatio-temporal events across France. This procedure is furthermore adapted to the SCOPE Hydro 25-member ensemble to characterize in a probabilistic way unrecorded historical events at the national scale. Extreme low-flow events are described and compared in a spatially and temporally homogeneous way over 140 years on a large set of catchments. Results highlight well-known recent events like 1976 or 1989-1990, but also older and relatively forgotten ones like the 1878 and 1893 events. These results contribute to improving our knowledge of historical events and provide a selection of benchmark events for climate change adaptation purposes. Moreover, this study allows for further detailed analyses of the effect of climate variability and anthropogenic climate change on low-flow hydrology at the scale of France.

  4. Pneumoretroperitoneum and Perirenal Air Associated With Pneumothorax in an Extremely Low-Birth-Weight Infant

    Directory of Open Access Journals (Sweden)

    Belma Saygili Karagol

    2011-02-01

    Full Text Available Pneumothorax-associated pneumoretroperitoneum and perirenal air have rarely been reported in infants. We report a case of an extremely low-birth-weight infant who developed pneumoretroperitoneum and perirenal air associated with tension pneumothorax and deteriorated acutely despite prompt pleural water-seal vacuum drainage system insertion. Our aim in presenting this case report is to emphasize keeping in mind that there could be extrapleural air leaks, such as pneumoretroperitoneum in patients with pneumothorax.

  5. Neurodevelopmental outcomes of triplets or higher-order extremely low birth weight infants.

    Science.gov (United States)

    Wadhawan, Rajan; Oh, William; Vohr, Betty R; Wrage, Lisa; Das, Abhik; Bell, Edward F; Laptook, Abbot R; Shankaran, Seetha; Stoll, Barbara J; Walsh, Michele C; Higgins, Rosemary D

    2011-03-01

    Extremely low birth weight twins have a higher rate of death or neurodevelopmental impairment than singletons. Higher-order extremely low birth weight multiple births may have an even higher rate of death or neurodevelopmental impairment. Extremely low birth weight (birth weight 401-1000 g) multiple births born in participating centers of the Neonatal Research Network between 1996 and 2005 were assessed for death or neurodevelopmental impairment at 18 to 22 months' corrected age. Neurodevelopmental impairment was defined by the presence of 1 or more of the following: moderate to severe cerebral palsy; mental developmental index score or psychomotor developmental index score less than 70; severe bilateral deafness; or blindness. Infants who died within 12 hours of birth were excluded. Maternal and infant demographic and clinical variables were compared among singleton, twin, and triplet or higher-order infants. Logistic regression analysis was performed to establish the association between singletons, twins, and triplet or higher-order multiples and death or neurodevelopmental impairment, controlling for confounding variables that may affect death or neurodevelopmental impairment. Our cohort consisted of 8296 singleton, 2164 twin, and 521 triplet or higher-order infants. The risk of death or neurodevelopmental impairment was increased in triplets or higher-order multiples when compared with singletons (adjusted odds ratio: 1.7 [95% confidence interval: 1.29-2.24]), and there was a trend toward an increased risk when compared with twins (adjusted odds ratio: 1.27 [95% confidence: 0.95-1.71]). Triplet or higher-order births are associated with an increased risk of death or neurodevelopmental impairment at 18 to 22 months' corrected age when compared with extremely low birth weight singleton infants, and there was a trend toward an increased risk when compared with twins.

  6. Extremely Low Mass: The Circumstellar Envelope of a Potential Proto-Brown Dwarf

    Science.gov (United States)

    Wiseman, Jennifer

    2011-01-01

    What is the environment for planet formation around extremely low mass stars? Is the environment around brown dwarfs and extremely low mass stars conducive and sufficiently massive for planet production? The determining conditions may be set very early in the process of the host object's formation. IRAS 16253-2429, the source of the Wasp-Waist Nebula seen in Spitzer IRAC images, is an isolated, very low luminosity ("VeLLO") Class 0 protostar in the nearby rho Ophiuchi cloud. We present VLA ammonia mapping observations of the dense gas envelope feeding the central core accreting system. We find a flattened envelope perpendicular to the outflow axis, and gas cavities that appear to cradle the outflow lobes as though carved out by the flow and associated (apparently precessing) jet, indicating environmental disruption. Based on the NH3 (1,1) and (2,2) emission distribution, we derive the mass, velocity fields and temperature distribution for the envelope. We discuss the combined evidence for this source to be one of the youngest and lowest mass sources in formation yet known, and discuss the ramifications for planet formation potential in this extremely low mass system.

  7. Two types of magnetospheric ELF chorus and their substorm dependences

    International Nuclear Information System (INIS)

    Tsurutani, B.T.; Smith, E.J.

    1977-01-01

    Extremely low frequency (10--1500 Hz) magnetospheric chorus has been analyzed to investigate a possible dependence on substorms. Care was taken to separate effects from temporal effects by analyzing an entire year of data acquired by the Ogo 5 search coil magnetometer. A major finding of the study of spatial dependences is that chorus occurs principally in two magnetic latitude regions. Equatorial chorus is detected near the equator, and high-latitude chorus is found at magnetic latitudes above 15 0 . When chorus in these two regions is analyzed separately, substorm dependences become apparent. Comparisons with AE indicate that equatorial chorus occurs primarily during substorms. High-latitude chorus is not strongly dependent on AE and often occurs during intervals of prolonged quiet with AE 0 , a region where cyclotron resonance is most efficient. The L value of maximum chorus occurrence increases from 5--8 postmidnight to 7--11 postdawn, a dependence which is consistent with generation by electrons which have undergone drift shell splitting. Delay times between substorms and the onset of equatorial chorus are consistent with a gradient drift of approx.25-keV electrons. Equatorial postmidnight chorus and postdawn chorus have similar occurrence rates and wave intensities. The maximum chorus ocurrence rates are 54% postmidnight and 56% postdawn

  8. Percutaneous evacuation of diffuse pulmonary interstitial emphysema by lung puncture in a baby with extremely low birth weight: a case report

    Directory of Open Access Journals (Sweden)

    Watanabe Masahiro

    2012-09-01

    Full Text Available Abstract Introduction Pulmonary interstitial emphysema is a serious complication of mechanical ventilation and can become life-threatening if progression occurs. Therapeutic lung puncture is a treatment option for severe pulmonary interstitial emphysema but has a limited use in babies with extremely low birth weight. We present a case of pulmonary interstitial emphysema in a Japanese baby (1-day-old boy with extremely low birth weight. The emphysema was successfully decompressed by therapeutic lung puncture performed with a trocar catheter. Case presentation The baby was born with a weight of 420g, which, to the best of our knowledge, is the lowest reported birth weight among babies with pulmonary interstitial emphysema. A chest X-ray on postnatal day 2 revealed pulmonary interstitial emphysema, which gradually progressed to diffuse pseudocystic changes. His condition became life-threatening despite the use of high-frequency oscillatory ventilation and lateral decubitus positioning. We evacuated the pulmonary interstitial emphysema by lung puncture with a trocar catheter to avoid respiratory and cardiovascular collapse. This resulted in adequate evacuation of the emphysema and a dramatic improvement in his clinical condition. Conclusions Therapeutic lung puncture performed with a trocar catheter is beneficial in babies with extremely low birth weight and diffuse pulmonary interstitial emphysema. This treatment option may be broadly applicable, especially in an emergency situation.

  9. Health-related quality of life for extremely low birth weight adolescents in Canada, Germany, and the Netherlands

    NARCIS (Netherlands)

    Verrips, E.; Vogels, T.; Saigal, S.; Wolke, D.; Meyer, R.; Hoult, L.; Verloove-Vanhorick, S.P.

    2008-01-01

    OBJECTIVE.The goal was to compare health-related quality of life of 12- to 16-year-old adolescents born at an extremely low birth weight in regional cohorts from Ontario (Canada), Bavaria (Germany), and the Netherlands. METHODS. Patients were extremely low birth weight survivors from Canada,

  10. Cellular ELF signals as a possible tool in informative medicine.

    Science.gov (United States)

    Foletti, Alberto; Lisi, Antonella; Ledda, Mario; de Carlo, Flavia; Grimaldi, Settimio

    2009-01-01

    According to Quantum Electro-Dynamical Theory by G. Preparata, liquid water can be viewed as an equilibrium between of two components: coherent and incoherent ones. The coherent component is contained within spherical so called "coherence domains" (CDs) where all molecules synchronously oscillate with the same phase. CDs are surrounded by the incoherent component where molecules oscillate with casual phases regarding each other. The existence of coherent domain in water has been demonstrated in a set of experiments on pure water exposed to high voltage, under this condition the electric field concentrates inside the water, arranging the water molecules to form high ordered structure. Recently has been studied the influence of combined static and alternating parallel magnetic fields on the current through the aqueous solution of glutamic acid; outlining the relevance of low frequency electro-magnetic field in interacting with biological target. Additional results demonstrate that at combined static and alternating parallel, magnetic fields matching the ion cyclotron energy resonance of a particular charged molecule into biological tissue an intrinsic weak magnetic field is generated by ion currents in the cell. These results should increase the reliability and the clinical feasibility of the use of electromagnetic field, tuned at ion cyclotron resonance of charged molecules, as a biophysical approach to interfere with biological mechanisms. We demonstrate that Exposure of human epithelial cell to ion cyclotron energy resonance generated by a commercial electromedical device (Vega select 719) tuned to calcium ion at 7 Hz act as a differentiation factor, thus opening up the possibility to use particular extremely low frequency electro magnetic field protocols, in informative medicine.

  11. ELROI Extremely Low Resource Optical Identifier. A license plate for your satellite, and more.

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-18

    ELROI (Extremely Low Resource Optical Identifier) is a license plate for your satellite; a small tag that flashes an optical identification code that can be read by a small telescope on the ground. The final version of the tag will be the size of a thick postage stamp and fully autonomous: you can attach it to everything that goes into space, including small cubesats and inert debris like rocket stages, and it will keep blinking even after the satellite is shut down, reliably identifying the object from launch until re-entry.

  12. Review of Studies Concerning Electromagnetic Field (EMF Exposure Assessment in Europe: Low Frequency Fields (50 Hz–100 kHz

    Directory of Open Access Journals (Sweden)

    Peter Gajšek

    2016-09-01

    Full Text Available We aimed to review the findings of exposure assessment studies done in European countries on the exposure of the general public to low frequency electric and magnetic fields (EMFs of various frequencies. The study shows that outdoor average extremely low frequency magnetic fields (ELF-MF in public areas in urban environments range between 0.05 and 0.2 µT in terms of flux densities, but stronger values (of the order of a few µT may occur directly beneath high-voltage power lines, at the walls of transformer buildings, and at the boundary fences of substations. In the indoor environment, high values have been measured close to several domestic appliances (up to the mT range, some of which are held close to the body, e.g., hair dryers, electric shavers. Common sources of exposure to intermediate frequencies (IF include induction cookers, compact fluorescent lamps, inductive charging systems for electric cars and security or anti-theft devices. No systematic measurement surveys or personal exposimetry data for the IF range have been carried out and only a few reports on measurements of EMFs around such devices are mentioned. According to the available European exposure assessment studies, three population exposure categories were classified by the authors regarding the possible future risk analysis. This classification should be considered a crucial advancement for exposure assessment, which is a mandatory step in any future health risk assessment of EMFs exposure.

  13. Review of Studies Concerning Electromagnetic Field (EMF) Exposure Assessment in Europe: Low Frequency Fields (50 Hz–100 kHz)

    Science.gov (United States)

    Gajšek, Peter; Ravazzani, Paolo; Grellier, James; Samaras, Theodoros; Bakos, József; Thuróczy, György

    2016-01-01

    We aimed to review the findings of exposure assessment studies done in European countries on the exposure of the general public to low frequency electric and magnetic fields (EMFs) of various frequencies. The study shows that outdoor average extremely low frequency magnetic fields (ELF-MF) in public areas in urban environments range between 0.05 and 0.2 µT in terms of flux densities, but stronger values (of the order of a few µT) may occur directly beneath high-voltage power lines, at the walls of transformer buildings, and at the boundary fences of substations. In the indoor environment, high values have been measured close to several domestic appliances (up to the mT range), some of which are held close to the body, e.g., hair dryers, electric shavers. Common sources of exposure to intermediate frequencies (IF) include induction cookers, compact fluorescent lamps, inductive charging systems for electric cars and security or anti-theft devices. No systematic measurement surveys or personal exposimetry data for the IF range have been carried out and only a few reports on measurements of EMFs around such devices are mentioned. According to the available European exposure assessment studies, three population exposure categories were classified by the authors regarding the possible future risk analysis. This classification should be considered a crucial advancement for exposure assessment, which is a mandatory step in any future health risk assessment of EMFs exposure. PMID:27598182

  14. DISCOVERY OF A BRIGHT, EXTREMELY LOW MASS WHITE DWARF IN A CLOSE DOUBLE DEGENERATE SYSTEM

    International Nuclear Information System (INIS)

    Vennes, S.; Kawka, A.; Nemeth, P.; Thorstensen, J. R.; Skinner, J. N.; Pigulski, A.; Steslicki, M.; Kolaczkowski, Z.; Srodka, P.

    2011-01-01

    We report the discovery of a bright (V ∼ 13.7), extremely low mass white dwarf in a close double degenerate system. We originally selected GALEX J171708.5+675712 for spectroscopic follow-up among a group of white dwarf candidates in an ultraviolet-optical reduced proper-motion diagram. The new white dwarf has a mass of 0.18 M sun and is the primary component of a close double degenerate system (P = 0.246137 days, K 1 = 288 km s -1 ) comprising a fainter white dwarf secondary with M 2 ∼ 0.9 M sun . Light curves phased with the orbital ephemeris show evidence of relativistic beaming and weaker ellipsoidal variations. The light curves also reveal secondary eclipses (depth ∼8 mmag) while the primary eclipses appear partially compensated by the secondary gravitational deflection and are below detection limits. Photospheric abundance measurements show a nearly solar composition of Si, Ca, and Fe (0.1-1 sun), while the normal kinematics suggest a relatively recent formation history. Close binary evolutionary scenarios suggest that extremely low mass white dwarfs form via a common-envelope phase and possible Roche lobe overflow.

  15. Direct synthesis of ultrathin SOI structure by extremely low-energy oxygen implantation

    Energy Technology Data Exchange (ETDEWEB)

    Hoshino, Yasushi, E-mail: yhoshino@kanagawa-u.ac.jp; Yachida, Gosuke; Inoue, Kodai; Toyohara, Taiga; Nakata, Jyoji [Department of mathematics and physics, Kanagawa University, 2946, Tsuchiya, Hiratsuka, Kanagawa 259-1293 (Japan)

    2016-06-15

    We performed extremely low-energy {sup 16}O{sup +} implantation at 10 keV (R{sub p} ∼ 25 nm) followed by annealing aiming at directly synthesizing an ultrathin Si layer separated by a buried SiO{sub 2} layer in Si(001) substrates, and then investigated feasible condition of recrystallization and stabilization of the superficial Si and the buried oxide layer by significantly low temperature annealing. The elemental compositions were analyzed by Rutherford backscattering (RBS) and secondary ion mass spectroscopy (SIMS). The crystallinity of the superficial Si layer was quantitatively confirmed by ananlyzing RBS-channeling spectra. Cross-sectional morphologies and atomic configurations were observed by transmission electron microscope (TEM). As a result, we succeeded in directly synthesizing an ultrathin single-crystalline silicon layer with ≤20 nm thick separated by a thin buried stoichiometric SiO{sub 2} layer with ≤20 nm thick formed by extremely low-energy {sup 16}O{sup +} implantation followed by surprisingly low temperature annealing at 1050{sup ∘} C.

  16. High incidence of rickets in extremely low birth weight infants with severe parenteral nutrition-associated cholestasis and bronchopulmonary dysplasia.

    Science.gov (United States)

    Lee, Soon Min; Namgung, Ran; Park, Min Soo; Eun, Ho Sun; Park, Kook In; Lee, Chul

    2012-12-01

    Risk factors for rickets of prematurity have not been re-examined since introduction of high mineral formula, particularly in ELBW infants. We analyzed the incidence and the risk factors of rickets in extremely low birth weight (ELBW) infants. As a retrospective case-control study from 2004 to 2008, risk factors were analyzed in 24 patients with rickets versus 31 patients without. The frequency of rickets in ELBW infants was 24/55 (44%). Infants with rickets were diagnosed at 48.2 ± 16.1 days of age, and improved by 85.3 ± 25.3 days. By radiologic evaluation, 29% were grade 1 rickets, 58% grade 2 and 13% grade 3. In univariate analysis, infants with rickets had significantly higher incidence of patent ductus arteriosus, parenteral nutrition associated cholestasis (PNAC), severe PNAC and moderate/severe bronchopulmonary dysplasia (BPD). In multiple regression analysis, after adjustment for gestation and birth weight, rickets significantly correlated with severe PNAC and with moderate/severe BPD. Serum peak alkaline phosphatase levels were significantly elevated in rickets (P rickets of prematurity remains high and the incidence of severe PNAC and moderate/severe BPD was significantly increased 18 and 3 times, respectively.

  17. Extreme Low Light Requirement for Algae Growth Underneath Sea Ice: A Case Study From Station Nord, NE Greenland

    Science.gov (United States)

    Hancke, Kasper; Lund-Hansen, Lars C.; Lamare, Maxim L.; Højlund Pedersen, Stine; King, Martin D.; Andersen, Per; Sorrell, Brian K.

    2018-02-01

    Microalgae colonizing the underside of sea ice in spring are a key component of the Arctic foodweb as they drive early primary production and transport of carbon from the atmosphere to the ocean interior. Onset of the spring bloom of ice algae is typically limited by the availability of light, and the current consensus is that a few tens-of-centimeters of snow is enough to prevent sufficient solar radiation to reach underneath the sea ice. We challenge this consensus, and investigated the onset and the light requirement of an ice algae spring bloom, and the importance of snow optical properties for light penetration. Colonization by ice algae began in May under >1 m of first-year sea ice with ˜1 m thick snow cover on top, in NE Greenland. The initial growth of ice algae began at extremely low irradiance (automated high-frequency temperature profiles. We propose that changes in snow optical properties, caused by temperature-driven snow metamorphosis, was the primary driver for allowing sufficient light to penetrate through the thick snow and initiate algae growth below the sea ice. This was supported by radiative-transfer modeling of light attenuation. Implications are an earlier productivity by ice algae in Arctic sea ice than recognized previously.

  18. Through-container, extremely low concentration detection of multiple chemical markers of counterfeit alcohol using a handheld SORS device.

    Science.gov (United States)

    Ellis, David I; Eccles, Rebecca; Xu, Yun; Griffen, Julia; Muhamadali, Howbeer; Matousek, Pavel; Goodall, Ian; Goodacre, Royston

    2017-09-21

    Major food adulteration incidents occur with alarming frequency and are episodic, with the latest incident, involving the adulteration of meat from 21 producers in Brazil supplied to 60 other countries, reinforcing this view. Food fraud and counterfeiting involves all types of foods, feed, beverages, and packaging, with the potential for serious health, as well as significant economic and social impacts. In the spirit drinks sector, counterfeiters often 'recycle' used genuine packaging, or employ good quality simulants. To prove that suspect products are non-authentic ideally requires accurate, sensitive, analysis of the complex chemical composition while still in its packaging. This has yet to be achieved. Here, we have developed handheld spatially offset Raman spectroscopy (SORS) for the first time in a food or beverage product, and demonstrate the potential for rapid in situ through-container analysis; achieving unequivocal detection of multiple chemical markers known for their use in the adulteration and counterfeiting of Scotch whisky, and other spirit drinks. We demonstrate that it is possible to detect a total of 10 denaturants/additives in extremely low concentrations without any contact with the sample; discriminate between and within multiple well-known Scotch whisky brands, and detect methanol concentrations well below the maximum human tolerable level.

  19. ELF wave generation in the ionosphere using pulse modulated HF heating: initial tests of a technique for increasing ELF wave generation efficiency

    Directory of Open Access Journals (Sweden)

    R. Barr

    1999-06-01

    Full Text Available This paper describes the results of a preliminary study to determine the effective heating and cooling time constants of ionospheric currents in a simulated modulated HF heating, `beam painting' configuration. It has been found that even and odd harmonics of the fundamental ELF wave used to amplitude modulate the HF heater are sourced from different regions of the ionosphere which support significantly different heating and cooling time constants. The fundamental frequency and its odd harmonics are sourced in a region of the ionosphere where the heating and cooling time constants are about equal. The even harmonics on the other hand are sourced from regions of the ionosphere characterised by ratios of cooling to heating time constant greater than ten. It is thought that the even harmonics are sourced in the lower ionosphere (around 65 km where the currents are much smaller than at the higher altitudes around 78 km where the currents at the fundamental frequency and odd harmonics maximise.Key words. Electromagnetics (antennae · Ionosphere (active experiments · Radio science (non linear phenomena

  20. Early working memory in children born with extremely low birth weight: assessed by object permanence.

    Science.gov (United States)

    Lowe, Jean; MacLean, Peggy C; Shaffer, Michele L; Watterberg, Kristi

    2009-04-01

    Object permanence is considered the earliest method for assessing working memory. Factors affecting object permanence performance in a sample of two hundred and thirty-three 18- to 22-month olds born with extremely low birth weight were examined. It was hypothesized that object permanence would be directly related to emotional and attention regulation, that children with lower birth weight and higher illness severity would have more difficulty on the object permanence task, and that no ethnic/racial differences would be found, as this is considered a culturally unbiased task. Attainment of object permanence had a significant positive association with emotional and attention regulation, even after controlling the medical severity and socioeconomic factors. More girls than boys passed the object permanence items. There was no ethnic/racial difference on object permanence. Our findings indicate that object permanence may be a culturally fair way of assessing development, and emotional and attention regulation are potential avenues of intervention for such skill.

  1. Factors affecting development of motor skills in extremely low birth weight children.

    Science.gov (United States)

    O'Connor, Anna R; Birch, Eileen E; Spencer, Rand

    2009-01-01

    The aim of this study is to analyze the impact of ophthalmic and neonatal factors on motor development in extremely low birth weight (ELBW) children. Sixty-four ELBW children at least 3 years of age were recruited. Visual acuity (VA) was assessed using the Teller acuity cards (TACs) and a letter test, if possible. A validated questionnaire assessing 25 fine (part A) and 20 gross motor (part B) skills was administered to the parents. Data were collected on retinopathy of prematurity (ROP) zone, intraventricular haemorrhage (IVH), length of stay in hospital, and number of days on oxygen. Abnormal TAC acuity was associated with significantly lower scores on both parts A and B (part A: 21.5 versus 11.8, p development, particularly fine motor development.

  2. Space charge dosimeters for extremely low power measurements of radiation in shipping containers

    Science.gov (United States)

    Britton, Jr; Charles, L [Alcoa, TN; Buckner, Mark A [Oak Ridge, TN; Hanson, Gregory R [Clinton, TN; Bryan, William L [Knoxville, TN

    2011-04-26

    Methods and apparatus are described for space charge dosimeters for extremely low power measurements of radiation in shipping containers. A method includes in situ polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method includes arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.

  3. Bordetella bronchiseptica Pneumonia in an Extremely-Low-Birth-Weight Neonate

    Directory of Open Access Journals (Sweden)

    Yuk Joseph Ting

    2011-12-01

    Full Text Available Bordetella bronchiseptica, a gram-negative coccobacillus, is a common veterinary pathogen. In both domestic and wild animals, this bacterium causes respiratory infections including infectious tracheobronchitis in dogs and atrophic rhinitis in swine. Human infections are rare and have been documented in immunocompromised hosts. Here, we describe an extremely-low-birth-weight infant with B. bronchiseptica pneumonia. This is the first report that describes the microorganism's responsibility in causing nosocomial infection in a preterm neonate. He recovered uneventfully after a course of meropenem. It is possible that the bacteria colonize the respiratory tracts of our health care workers or parents who may have had contact with pets and then transmitted the bacterium to our patient. Follow-up until 21 months of age showed normal growth and development. He did not suffer from any significant residual respiratory disease.

  4. Cardiovascular Responses to Psychosocial Stress Reflect Motivation State in Adults Born at Extremely Low Birth Weight

    Directory of Open Access Journals (Sweden)

    Karen J. Mathewson PhD

    2015-03-01

    Full Text Available Background. Adults born extremely preterm appear to have more difficulty managing the stresses of early adulthood than their term-born peers. Objective. To examine the effects of being born at extremely low birth weight (ELBW; birth weight < 1000 g versus at full term on cardiovascular responses to stress. Method. Cardiovascular responses were elicited during administration of a widely used laboratory stressor, the Trier Social Stress Test (TSST. Results. Term-born adults exhibited a larger decrease in total peripheral resistance and larger increase in cardiac output for TSST performance, reflecting greater resilience, than did ELBW adults. Furthermore, in ELBW participants but not controls, cardiovascular responses were correlated with anxiety, suggesting that their responses reflected feelings of stress. Conclusions. Skills-training and practice with relevant stressors may be necessary to increase the personal resources of ELBW participants for managing stress as they transition to adulthood.

  5. Extreme low thermal conductivity in nanoscale 3D Si phononic crystal with spherical pores.

    Science.gov (United States)

    Yang, Lina; Yang, Nuo; Li, Baowen

    2014-01-01

    In this work, we propose a nanoscale three-dimensional (3D) Si phononic crystal (PnC) with spherical pores, which can reduce the thermal conductivity of bulk Si by a factor up to 10,000 times at room temperature. Thermal conductivity of Si PnCs depends on the porosity, for example, the thermal conductivity of Si PnCs with porosity 50% is 300 times smaller than that of bulk Si. The phonon participation ratio spectra demonstrate that more phonons are localized as the porosity increases. The thermal conductivity is insensitive to the temperature changes from room temperature to 1100 K. The extreme-low thermal conductivity could lead to a larger value of ZT than unity as the periodic structure affects very little the electric conductivity.

  6. Disseminated candidemia refractory to caspofungin therapy in an infant with extremely low birth weight

    Directory of Open Access Journals (Sweden)

    Meng-Ju Li

    2012-01-01

    Full Text Available Systemic fungal infections have high morbidity and mortality rates in neonates, especially neonates with an extremely low birth weight (ELBW. Here, we describe a 21-day-old ELBW female infant with an amphotericin B-unresponsive congenital Candida albicans infection that was treated with caspofungin. Blood sterilization was performed during the first episode, but a second episode of candidemia occurred after the discontinuation of caspofungin. Blood sterilization was again performed during the second round of caspofungin treatment, but fungal endocarditis and renal fungal balls still developed during the second episode. Caspofungin can be considered for invasive candidiasis in premature infants, especially in life-threatening situations. As for the focal lesions, more aggressive treatments other than just parenteral antibiotics should be considered. The literature regarding caspofungin therapy for neonatal candidiasis is also reviewed.

  7. Linking Early Adversity, Emotion Dysregulation, and Psychopathology: The Case of Extremely Low Birth Weight Infants

    Directory of Open Access Journals (Sweden)

    Lauren A. Drvaric

    2013-01-01

    Full Text Available The ability to regulate emotion is a crucial process that humans utilize in order to adapt to the demands of environmental constraints. Individuals exposed to early adverse life events such as being born at an extremely low birth weight (ELBW, 501–1000 g are known to have problems regulating emotion which have been linked to the development of psychopathology in this population. Recent studies have used psychophysiological measures, such as electroencephalogram (EEG and cardiac vagal tone, to index emotion regulatory processes. The purpose of this paper was three-fold: (1 to investigate the relation between ELBW and emotion regulation issues (pathway 1, (2 to review studies investigating the relation between early emotion regulation and later internalizing problems (pathway 2; and (3 to provide a model in which two psychophysiological measures (i.e., frontal EEG asymmetry and cardiac vagal tone are suggested to understand the proposed conceptual pathways in the relation between ELBW and psychopathology.

  8. Outcome of extremely low birth weight infants who received delivery room cardiopulmonary resuscitation.

    Science.gov (United States)

    Wyckoff, Myra H; Salhab, Walid A; Heyne, Roy J; Kendrick, Douglas E; Stoll, Barbara J; Laptook, Abbot R

    2012-02-01

    To determine whether delivery room cardiopulmonary resuscitation (DR-CPR) independently predicts morbidities and neurodevelopmental impairment (NDI) in extremely low birth weight infants. We conducted a cohort study of infants born with birth weight of 401 to 1000 g and gestational age of 23 to 30 weeks. DR-CPR was defined as chest compressions, medications, or both. Logistic regression was used to determine associations among DR-CPR and morbidities, mortality, and NDI at 18 to 24 months of age (Bayley II mental or psychomotor index blindness, or deafness). Data are adjusted ORs with 95% CIs. Of 8685 infants, 1333 (15%) received DR-CPR. Infants who received DR-CPR had lower birth weight (708±141 g versus 764±146g, PCPR had more pneumothoraces (OR, 1.28; 95% CI, 1.48-2.99), grade 3 to 4 intraventricular hemorrhage (OR, 1.47; 95% CI, 1.23-1.74), bronchopulmonary dysplasia (OR, 1.34; 95% CI, 1.13-1.59), death by 12 hours (OR, 3.69; 95% CI, 2.98-4.57), and death by 120 days after birth (OR, 2.22; 95% CI, 1.93-2.57). Rates of NDI in survivors (OR, 1.23; 95% CI, 1.02-1.49) and death or NDI (OR, 1.70; 95% CI, 1.46-1.99) were higher for DR-CPR infants. Only 14% of DR-CPR recipients with 5-minute Apgar score CPR is a prognostic marker for higher rates of mortality and NDI for extremely low birth weight infants. New DR-CPR strategies are needed for this population. Copyright © 2012 Mosby, Inc. All rights reserved.

  9. Learning Disabilities in Extremely Low Birth Weight Children and Neurodevelopmental Profiles at Preschool Age.

    Science.gov (United States)

    Squarza, Chiara; Picciolini, Odoardo; Gardon, Laura; Giannì, Maria L; Murru, Alessandra; Gangi, Silvana; Cortinovis, Ivan; Milani, Silvano; Mosca, Fabio

    2016-01-01

    At school age extremely low birth weight (ELBW) and extremely low gestational age (ELGAN) children are more likely to show Learning Disabilities (LDs) and difficulties in emotional regulation. The aim of this study was to investigate the incidence of LDs at school age and to detect neurodevelopmental indicators of risk for LDs at preschool ages in a cohort of ELBW/ELGAN children with broadly average intelligence. All consecutively newborns 2001-2006 admitted to the same Institution entered the study. Inclusion criteria were BW disabilities, genetic abnormalities, and/or a Developmental Quotient below normal limits (learning disabilities at school age was investigated through a parent-report questionnaire at children's age range 9-10 years. Neurodevelopmental profiles were assessed through the Griffiths Mental Development Scales at 1 and 2 years of corrected age and at 3, 4, 5, and 6 years of chronological age and were analyzed comparing two groups of children: those with LDs and those without. At school age 24 on 102 (23.5%) of our ELBW/ELGAN children met criteria for LDs in one or more areas, with 70.8% comorbidity with emotional/attention difficulties. Children with LDs scored significantly lower in the Griffiths Locomotor and Language subscales at 2 years of corrected age and in the Personal-social, Performance and Practical Reasoning subscales at 5 years of chronological age. Our findings suggest that, among the early developmental indicators of adverse school outcome, there is a poor motor experimentation, language delay, and personal-social immaturity. Cognitive rigidity and poor ability to manage practical situations also affect academic attainment. Timely detection of these early indicators of risk is crucial to assist the transition to school.

  10. The Modified Checklist for Autism in Toddlers in extremely low gestational age newborns: individual items associated with motor, cognitive, vision and hearing limitations.

    Science.gov (United States)

    Luyster, Rhiannon J; Kuban, Karl C K; O'Shea, T Michael; Paneth, Nigel; Allred, Elizabeth N; Leviton, Alan

    2011-07-01

    The Modified Checklist for Autism in Toddlers (M-CHAT) has yielded elevated rates of screening failure for children born preterm or with low birthweight. We extended these findings with a detailed examination of M-CHAT items in a large sample of children born at extremely low gestational age. The sample was grouped according to children's current limitations and degree of impairment. The aim was to better understand how disabilities might influence M-CHAT scores. Fourteen participating institutions of the Extremely Low Gestational Age Newborns (ELGAN) Study prospectively collected information about 1086 infants who were born before the 28th week of gestation and had an assessment at age 24-months. The 24-month visit included a neurological assessment, the Bayley Scales of Infant Development, Second edition (BSID-II), M-CHAT and a medical history form. Outcome measures included the distribution of failed M-CHAT items among groups classified according to cerebral palsy diagnosis, gross motor function, BSID-II scores and vision or hearing impairments. M-CHAT items were failed more frequently by children with concurrently identified impairments (motor, cognitive, vision and hearing). In addition, the frequency of item failure increased with the severity of impairment. The failed M-CHAT items were often, but not consistently, related to children's specific impairments. Importantly, four of the six M-CHAT 'critical items' were commonly affected by presence and severity of concurrent impairments. The strong association between impaired sensory or motor function and M-CHAT results among extremely low gestational age children suggests that such impairments might give rise to false positive M-CHAT screening. © 2011 Blackwell Publishing Ltd.

  11. SDSS J184037.78+642312.3: THE FIRST PULSATING EXTREMELY LOW MASS WHITE DWARF

    Energy Technology Data Exchange (ETDEWEB)

    Hermes, J. J.; Montgomery, M. H.; Winget, D. E. [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States); Brown, Warren R.; Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden St, Cambridge, MA 02138 (United States); Kilic, Mukremin, E-mail: jjhermes@astro.as.utexas.edu [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States)

    2012-05-10

    We report the discovery of the first pulsating extremely low mass (ELM) white dwarf (WD), SDSS J184037.78+642312.3 (hereafter J1840). This DA (hydrogen-atmosphere) WD is by far the coolest and the lowest-mass pulsating WD, with T{sub eff} = 9100 {+-} 170 K and log g = 6.22 {+-} 0.06, which corresponds to a mass of {approx}0.17 M{sub Sun }. This low-mass pulsating WD greatly extends the DAV (or ZZ Ceti) instability strip, effectively bridging the log g gap between WDs and main-sequence stars. We detect high-amplitude variability in J1840 on timescales exceeding 4000 s, with a non-sinusoidal pulse shape. Our observations also suggest that the variability is multi-periodic. The star is in a 4.6 hr binary with another compact object, most likely another WD. Future, more extensive time-series photometry of this ELM WD offers the first opportunity to probe the interior of a low-mass, presumably He-core WD using the tools of asteroseismology.

  12. THE ELM SURVEY. III. A SUCCESSFUL TARGETED SURVEY FOR EXTREMELY LOW MASS WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Warren R.; Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden St., Cambridge, MA 02138 (United States); Kilic, Mukremin [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States); Allende Prieto, Carlos, E-mail: wbrown@cfa.harvard.edu, E-mail: skenyon@cfa.harvard.edu, E-mail: kilic@ou.edu, E-mail: callende@iac.es [Instituto de Astrofisica de Canarias, E-38205, La Laguna, Tenerife (Spain)

    2012-01-10

    Extremely low mass (ELM) white dwarfs (WDs) with masses < 0.25 M{sub Sun} are rare objects that result from compact binary evolution. Here, we present a targeted spectroscopic survey of ELM WD candidates selected by color. The survey is 71% complete and has uncovered 18 new ELM WDs. Of the seven ELM WDs with follow-up observations, six are short-period binaries and four have merger times less than 5 Gyr. The most intriguing object, J1741+6526, likely has either a pulsar companion or a massive WD companion making the system a possible supernova Type Ia or an Ia progenitor. The overall ELM survey has now identified 19 double degenerate binaries with <10 Gyr merger times. The significant absence of short orbital period ELM WDs at cool temperatures suggests that common envelope evolution creates ELM WDs directly in short period systems. At least one-third of the merging systems are halo objects, thus ELM WD binaries continue to form and merge in both the disk and the halo.

  13. SDSS J184037.78+642312.3: THE FIRST PULSATING EXTREMELY LOW MASS WHITE DWARF

    International Nuclear Information System (INIS)

    Hermes, J. J.; Montgomery, M. H.; Winget, D. E.; Brown, Warren R.; Kenyon, Scott J.; Kilic, Mukremin

    2012-01-01

    We report the discovery of the first pulsating extremely low mass (ELM) white dwarf (WD), SDSS J184037.78+642312.3 (hereafter J1840). This DA (hydrogen-atmosphere) WD is by far the coolest and the lowest-mass pulsating WD, with T eff = 9100 ± 170 K and log g = 6.22 ± 0.06, which corresponds to a mass of ∼0.17 M ☉ . This low-mass pulsating WD greatly extends the DAV (or ZZ Ceti) instability strip, effectively bridging the log g gap between WDs and main-sequence stars. We detect high-amplitude variability in J1840 on timescales exceeding 4000 s, with a non-sinusoidal pulse shape. Our observations also suggest that the variability is multi-periodic. The star is in a 4.6 hr binary with another compact object, most likely another WD. Future, more extensive time-series photometry of this ELM WD offers the first opportunity to probe the interior of a low-mass, presumably He-core WD using the tools of asteroseismology.

  14. THE ELM SURVEY. III. A SUCCESSFUL TARGETED SURVEY FOR EXTREMELY LOW MASS WHITE DWARFS

    International Nuclear Information System (INIS)

    Brown, Warren R.; Kenyon, Scott J.; Kilic, Mukremin; Allende Prieto, Carlos

    2012-01-01

    Extremely low mass (ELM) white dwarfs (WDs) with masses ☉ are rare objects that result from compact binary evolution. Here, we present a targeted spectroscopic survey of ELM WD candidates selected by color. The survey is 71% complete and has uncovered 18 new ELM WDs. Of the seven ELM WDs with follow-up observations, six are short-period binaries and four have merger times less than 5 Gyr. The most intriguing object, J1741+6526, likely has either a pulsar companion or a massive WD companion making the system a possible supernova Type Ia or an Ia progenitor. The overall ELM survey has now identified 19 double degenerate binaries with <10 Gyr merger times. The significant absence of short orbital period ELM WDs at cool temperatures suggests that common envelope evolution creates ELM WDs directly in short period systems. At least one-third of the merging systems are halo objects, thus ELM WD binaries continue to form and merge in both the disk and the halo.

  15. 3D MODEL ATMOSPHERES FOR EXTREMELY LOW-MASS WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Tremblay, P.-E. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD, 21218 (United States); Gianninas, A.; Kilic, M. [Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK, 73019 (United States); Ludwig, H.-G. [Zentrum für Astronomie der Universität Heidelberg, Landessternwarte, Königstuhl 12, D-69117 Heidelberg (Germany); Steffen, M. [Leibniz-Institut für Astrophysik Potsdam, An der Sternwarte 16, D-14482 Potsdam (Germany); Freytag, B. [Department of Physics and Astronomy at Uppsala University, Regementsvägen 1, Box 516, SE-75120 Uppsala (Sweden); Hermes, J. J., E-mail: tremblay@stsci.edu [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)

    2015-08-20

    We present an extended grid of mean three-dimensional (3D) spectra for low-mass, pure-hydrogen atmosphere DA white dwarfs (WDs). We use CO5BOLD radiation-hydrodynamics 3D simulations covering T{sub eff} = 6000–11,500 K and log g = 5–6.5 (g in cm s{sup −2}) to derive analytical functions to convert spectroscopically determined 1D temperatures and surface gravities to 3D atmospheric parameters. Along with the previously published 3D models, the 1D to 3D corrections are now available for essentially all known convective DA WDs (i.e., log g = 5–9). For low-mass WDs, the correction in temperature is relatively small (a few percent at the most), but the surface gravities measured from the 3D models are lower by as much as 0.35 dex. We revisit the spectroscopic analysis of the extremely low-mass (ELM) WDs, and demonstrate that the 3D models largely resolve the discrepancies seen in the radius and mass measurements for relatively cool ELM WDs in eclipsing double WD and WD + millisecond pulsar binary systems. We also use the 3D corrections to revise the boundaries of the ZZ Ceti instability strip, including the recently found ELM pulsators.

  16. Permissive hypotension in extremely low birth weight infants (≤1000 gm).

    Science.gov (United States)

    Ahn, So Yoon; Kim, Eun Sun; Kim, Jin Kyu; Shin, Jeong Hee; Sung, Se In; Jung, Ji Mi; Chang, Yun Sil; Park, Won Soon

    2012-07-01

    We performed this study to evaluate the safety of permissive hypotension management in extremely low birth weight infants (ELBWIs). Medical records of all inborn ELBWIs admitted to Samsung Medical Center from January 2004 to December 2008 were reviewed retrospectively. Of a total of 261 ELBWIs, 47 (18%) required treatment for hypotension (group T), 110 (42%) remained normotensive (group N), and 104 (40%) experienced more than one episode of hypotension without treatment (group P) during the first 72 hours of life. Treatment of hypotension included inotropic support and/or fluid loading. Birth weight and Apgar scores were significantly lower in the T group than the other two groups. In the N group, the rate of pathologically confirmed maternal chorioamnionitis was significantly higher than other two groups, and the rate was higher in the P group than the T group. After adjusting for covariate factors, no significant differences in mortality and major morbidities were found between the N and P groups. However, the mortality rate and the incidence of intraventricular hemorrhage (≥stage 3) and bronchopulmonary dysplasia (≥moderate) were significantly higher in the T group than the other two groups. Long term neurodevelopmental outcomes were not significantly different between the N and P groups. Close observation of hypotensive ELBWIs who showed good clinical perfusion signs without intervention allowed to avoid unnecessary medications and resulted in good neurological outcomes.

  17. Production of extremely low volatile organic compounds from biogenic emissions: Measured yields and atmospheric implications.

    Science.gov (United States)

    Jokinen, Tuija; Berndt, Torsten; Makkonen, Risto; Kerminen, Veli-Matti; Junninen, Heikki; Paasonen, Pauli; Stratmann, Frank; Herrmann, Hartmut; Guenther, Alex B; Worsnop, Douglas R; Kulmala, Markku; Ehn, Mikael; Sipilä, Mikko

    2015-06-09

    Oxidation products of monoterpenes and isoprene have a major influence on the global secondary organic aerosol (SOA) burden and the production of atmospheric nanoparticles and cloud condensation nuclei (CCN). Here, we investigate the formation of extremely low volatility organic compounds (ELVOC) from O3 and OH radical oxidation of several monoterpenes and isoprene in a series of laboratory experiments. We show that ELVOC from all precursors are formed within the first minute after the initial attack of an oxidant. We demonstrate that under atmospherically relevant concentrations, species with an endocyclic double bond efficiently produce ELVOC from ozonolysis, whereas the yields from OH radical-initiated reactions are smaller. If the double bond is exocyclic or the compound itself is acyclic, ozonolysis produces less ELVOC and the role of the OH radical-initiated ELVOC formation is increased. Isoprene oxidation produces marginal quantities of ELVOC regardless of the oxidant. Implementing our laboratory findings into a global modeling framework shows that biogenic SOA formation in general, and ELVOC in particular, play crucial roles in atmospheric CCN production. Monoterpene oxidation products enhance atmospheric new particle formation and growth in most continental regions, thereby increasing CCN concentrations, especially at high values of cloud supersaturation. Isoprene-derived SOA tends to suppress atmospheric new particle formation, yet it assists the growth of sub-CCN-size primary particles to CCN. Taking into account compound specific monoterpene emissions has a moderate effect on the modeled global CCN budget.

  18. Early Conventional MRI for Prediction of Neurodevelopmental Impairment in Extremely-Low-Birth-Weight Infants.

    Science.gov (United States)

    Slaughter, Laurel A; Bonfante-Mejia, Eliana; Hintz, Susan R; Dvorchik, Igor; Parikh, Nehal A

    2016-01-01

    Extremely-low-birth-weight (ELBW; ≤1,000 g) infants are at high risk for neurodevelopmental impairments. Conventional brain MRI at term-equivalent age is increasingly used for prediction of outcomes. However, optimal prediction models remain to be determined, especially for cognitive outcomes. The aim was to evaluate the accuracy of a data-driven MRI scoring system to predict neurodevelopmental impairments. 122 ELBW infants had a brain MRI performed at term-equivalent age. Conventional MRI findings were scored with a standardized algorithm and tested using a multivariable regression model to predict neurodevelopmental impairment, defined as one or more of the following at 18-24 months' corrected age: cerebral palsy, bilateral blindness, bilateral deafness requiring amplification, and/or cognitive/language delay. Results were compared with a commonly cited scoring system. In multivariable analyses, only moderate-to-severe gyral maturational delay was a significant predictor of overall neurodevelopmental impairment (OR: 12.6, 95% CI: 2.6, 62.0; p neurodevelopmental impairment/death. Diffuse cystic abnormality was a significant predictor of cerebral palsy (OR: 33.6, 95% CI: 4.9, 229.7; p neurodevelopmental impairment. In our cohort, conventional MRI at term-equivalent age exhibited high specificity in predicting neurodevelopmental outcomes. However, sensitivity was suboptimal, suggesting additional clinical factors and biomarkers are needed to enable accurate prognostication. © 2016 S. Karger AG, Basel.

  19. Microsystem for remote sensing of high energy radiation with associated extremely low photon flux densities

    Science.gov (United States)

    Otten, A.; Jain, V. K.

    2015-08-01

    This paper presents a microsystem for remote sensing of high energy radiation in extremely low flux density conditions. With wide deployment in mind, potential applications range from nuclear non-proliferation, to hospital radiation-safety. The daunting challenge is the low level of photon flux densities - emerging from a Scintillation Crystal (SC) on to a ~1 mm-square detector, which are a factor of 10000 or so lower than those acceptable to recently reported photonic chips (including `single-photon detection' chips), due to a combination of low Lux, small detector size, and short duration SC output pulses - on the order of 1 μs. These challenges are attempted to be overcome by the design of an innovative `System on a Chip' type microchip, with high detector sensitivity, and effective coupling from the SC to the photodetector. The microchip houses a tiny n+ diff p-epi photodiode (PD) as well as the associated analog amplification and other related circuitry, all fabricated in 0.5micron, 3-metal 2-poly CMOS technology. The amplification, together with pulse-shaping of the photocurrent-induced voltage signal, is achieved through a tandem of two capacitively coupled, double-cascode amplifiers. Included in the paper are theoretical estimates and experimental results.

  20. Discovery of Three Pulsating, Mixed-atmosphere, Extremely Low-mass White Dwarf Precursors

    Science.gov (United States)

    Gianninas, A.; Curd, Brandon; Fontaine, G.; Brown, Warren R.; Kilic, Mukremin

    2016-05-01

    We report the discovery of pulsations in three mixed-atmosphere, extremely low-mass white dwarf (ELM WD, M ≤slant 0.3 M ⊙) precursors. Following the recent discoveries of pulsations in both ELM and pre-ELM WDs, we targeted pre-ELM WDs with mixed H/He atmospheres with high-speed photometry. We find significant optical variability in all three observed targets with periods in the range 320-590 s, consistent in timescale with theoretical predictions of p-mode pulsations in mixed-atmosphere ≈0.18 M ⊙ He-core pre-ELM WDs. This represents the first empirical evidence that pulsations in pre-ELM WDs can only occur if a significant amount of He is present in the atmosphere. Future, more extensive, timeseries photometry of the brightest of the three new pulsators offers an excellent opportunity to constrain the thickness of the surface H layer, which regulates the cooling timescales for ELM WDs. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovação (Brazil).

  1. Morbidity in extreme low birth weight newborns hospitalized in a high risk public maternity

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    Derijulie Siqueira Sousa

    Full Text Available Abstract Objectives: to determine the prevalence of the most common morbidities in extremely low birth weight (ELBW infants hospitalized in a newborn intensive care unit (NICU and to evaluate the influence of these morbidities through the length of in-hospital stay. Methods: observational, longitudinal, prospective and analytical study in a high risk reference maternity NICU from Sergipe, realized with 158 ELBW infants admitted between March 2014 and April 2015. The analysis of the hospitalization time was realized through the Kaplan-Meier method. Results: the average weight of premature was 785,2g ± 138,2g. The gestational age vary from 22 to 35 weeks and the average was 26,8 weeks. Of those admitted at NICU, sixty three (39,9% were discharged and 95 (60,1% died. The time of hospitalization was influenced for morbidities as: patent ductus arteriosus (PDA, intraventricular hemorrhage and sepsis. Acute respiratory distress syndrome was the most common complication (157 - 99,4%. The incidence of persistent arterial duct, intraventricular hemorrhage, sepsis, hypothermia, hypoglycemia and retinopathy of prematurity was 39,2%, 17,1%, 32,3%,50,3%, 52,3% e 16,6% respectively. Conclusions: the morbidities from respiratory tract, cardiac, neurological and infectious were the most prevalent, whilst PDA, intraventricular hemorrhage and sepsis were the morbidities that significantly influenced the time of hospitalization.

  2. Anatomy-driven design of a prototype video laryngoscope for extremely low birth weight infants

    Science.gov (United States)

    Baker, Katherine; Tremblay, Eric; Karp, Jason; Ford, Joseph; Finer, Neil; Rich, Wade

    2010-11-01

    Extremely low birth weight (ELBW) infants frequently require endotracheal intubation for assisted ventilation or as a route for administration of drugs or exogenous surfactant. In adults and less premature infants, the risks of this intubation can be greatly reduced using video laryngoscopy, but current products are too large and incorrectly shaped to visualize an ELBW infant's airway anatomy. We design and prototype a video laryngoscope using a miniature camera set in a curved acrylic blade with a 3×6-mm cross section at the tip. The blade provides a mechanical structure for stabilizing the tongue and acts as a light guide for an LED light source, located remotely to avoid excessive local heating at the tip. The prototype is tested on an infant manikin and found to provide sufficient image quality and mechanical properties to facilitate intubation. Finally, we show a design for a neonate laryngoscope incorporating a wafer-level microcamera that further reduces the tip cross section and offers the potential for low cost manufacture.

  3. Risk factors of extubation failure in extremely low birth weight infants: a five year retrospective analysis.

    Science.gov (United States)

    Lee, Chao-Yi; Su, Bai-Horng; Lin, Tsung-Wen; Lin, Hung-Chih; Li, Tsai-Chung; Wang, Nai-Phon

    2002-01-01

    Extubation failure is one of the most serious complications in extremely low birth weight infants (ELBWI) on mechanical ventilation therapy. We performed a 5-year retrospective analysis to realize the status of extubation failure in ELBWI. Extubation failure was defined as requirements of re-intubation within 72 hours after extubation. The extubation failure rate was 21% (29/138). The mean birth body weight was 808.3 +/- 140.4 gm. The mean gestational age was 25.8 +/- 1.2 wks. The incidence of chronic lung disease (CLD) in infants with extubation failure was 100% (29/29). Apnea of prematurity 49% (14/29) and post-extubation atelectasis 39% (11/29) were the most common reasons for reintubation. The major microbiology findings which correlated with nosocomial pneumonia in infants with extubation failure were Acinetobacter baumanni (21%), Klebsiella pneumonia (21%), Pseudomonas aeroginosa (14%), and Methicillin resistant staphylococcus aureus (14%). In conclusion, post-extubation atelectasis and apnea were the most common reasons for reintubation. ELBWI with extubation failure had higher incidences of post-extubation atelectasis, CLD, and nosocomial pneumonia. Further prospective studies are needed in order to clarify the appropriate extubation program for ELBWI and to prevent post-extubation atelectasis and nosocomial pneumonia.

  4. Polycythemia, capillary rarefaction, and focal glomerulosclerosis in two adolescents born extremely low birth weight and premature.

    Science.gov (United States)

    Asada, Nariaki; Tsukahara, Takanori; Furuhata, Megumi; Matsuoka, Daisuke; Noda, Shunsuke; Naganuma, Kuniaki; Hashiguchi, Akinori; Awazu, Midori

    2017-07-01

    Low birthweight infants have a reduced number of nephrons and are at high risk of chronic kidney disease. Preterm birth and/or intrauterine growth restriction (IUGR) may also affect peritubular capillary development, as has been shown in other organs. We report two patients with a history of preterm birth and extremely low birthweight who showed polycythemia and renal capillary rarefaction. Patient 1 and 2, born at 25 weeks of gestation with a birthweight of 728 and 466 g, showed mild proteinuria at age 8 and 6 years, respectively. In addition to increasing proteinuria, hemoglobin levels became elevated towards adolescence and their serum erythropoietin (EPO) was high despite polycythemia. Light microscopic examination of renal biopsy specimens showed glomerular hypertrophy, focal segmental glomerulosclerosis, and only mild tubulointerstitial fibrosis. A decrease in the immunohistochemical staining of CD31 and CD34 endothelial cells in renal biopsy specimens was consistent with peritubular capillary rarefaction. Since kidney function was almost normal and fibrosis was not severe, we consider that the capillary rarefaction and polycythemia associated with elevated EPO levels were largely attributable to preterm birth and/or IUGR.

  5. Modified theoretical minimum emittance lattice for an electron storage ring with extreme-low emittance

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    Yi Jiao

    2011-05-01

    Full Text Available In the continuing efforts to reduce the beam emittance of an electron storage ring composed of theoretical minimum emittance (TME lattice, down to a level of several tens of picometers, nonlinear dynamics grows to be a great challenge to the performance of the storage ring because of the strong sextupoles needed to compensate for its large global natural chomaticities coupled with its small average dispersion function. To help in dealing with the challenge of nonlinear optimization, we propose a novel variation of theoretical minimum emittance (TME lattice, named as “modified-TME” lattice, with minimal emittance about 3 times of the exact theoretical minimum, while with more compact layout, lower phase advance per cell, smaller natural chromaticities, and more relaxed optical functions than that in a TME cell, by using horizontally defocusing quadrupole closer to the dipole or simply combined-function dipole with horizontally defocusing gradient. We present approximate scaling formulas to describe the relationships of the design parameters in a modified-TME cell. The applications of modified-TME lattice in the PEP-X storage ring design are illustrated and the proposed lattice appears a good candidate for synchrotron radiation light source with extremely low emittance.

  6. Gender-related clinical and immunological features of extremely low birth weight infants

    Directory of Open Access Journals (Sweden)

    G. N. Chistyakova

    2016-01-01

    Full Text Available Examinations were made in 35 boys and 39 girls with extremely low birth weight in order to identify gender-related clinical and immunological features. A comparison group consisted of 31 full-term newborns with early uncomplicated adaptation. The investigators determined the number of lymphocyte subpopulations and cytokine-producing cells (CD3+INF-γ+, CD3+IL-4+ by flow cytometry and the serum levels of cytokines (IL-4, IFN-γ and neopterin by enzyme immunoassay. A study of immunological parameters revealed that the boys had a smaller number of CD3+, CD4+, and CD8+ subpopulations, a reduced content of CD3+IL-4+ cells at birth, and low IL-4 production on the first day of life compared to the full-term neonates. The girls were recorded to have higher levels of neopterin and B cells on the first day of life, the quantitative characteristics of T lymphocytes were consistent with those in the full-term infants. The findings are indicative of the greater functional immaturity of the immune system in the preterm boys. 

  7. Intra-vesical knot of bladder catheter in an extremely low birthweight neonate: A case report

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    Paula M.Y. Tang

    2015-07-01

    Full Text Available Premature and extremely low birth weight (ELBW neonates are at high risk of developing multiple co-morbidities and often require urinary catheterization for various medical indications. Intra-vesical knotting of bladder catheter is a known but uncommon complication of this procedure. We report a case of an ELBW baby boy with a knotted bladder catheter requiring surgical retrieval. After an elective operation for the closure of patent ductus arteriosus, a 4 French urinary catheter was inserted into an ELBW baby boy for urine output monitoring and left in-situ. Resistance was encountered in attempt to remove the urinary catheter. Abdominal X Ray confirmed intra-vesical knotting of the tube. Knot unravelling by interventional radiology was attempted but was unsuccessful. Open extra-peritoneal bladder exploration was performed for the retrieval of the tightly knotted catheter. A 6 French transurethral Foley catheter was inserted for bladder drainage. Upon removal of the Foley's catheter on day 5 post op, the baby was able to void spontaneously. With literature review, we postulated the potential risk factors resulting in this potentially avoidable iatrogenic unusual complication. Recommendations were suggested to avoid further incidences.

  8. Specialization to Extremely Low-Nutrient Soils Limits the Nutritional Adaptability of Plant Lineages.

    Science.gov (United States)

    Verboom, G Anthony; Stock, William D; Cramer, Michael D

    2017-06-01

    Specialization to extreme selective situations promotes the acquisition of traits whose coadaptive integration may compromise evolutionary flexibility and adaptability. We test this idea in the context of the foliar stoichiometry of plants native to the South African Cape. Whereas foliar concentrations of nitrogen, phosphorus (P), potassium (K), calcium, magnesium, and sodium showed strong phylogenetic signal, as did the foliar ratios of these nutrients to P, the same was not true of the corresponding soil values. In addition, although foliar traits were often related to soil values, the coefficients of determination were consistently low. These results identify foliar stoichiometry as having a strong genetic component, with variation in foliar nutrient concentrations, especially [P] and [K], being identified as potentially adaptive. Comparison of stoichiometric variation across 11 similarly aged clades revealed consistently low foliar nutrient concentrations in lineages showing specialization to extremely low-nutrient fynbos heathlands. These lineages also display lower rates of evolution of these traits as well as a reduced tendency for foliar [P] to track soil [P]. Reduced evolutionary lability and adaptability in the nutritional traits of fynbos-specialist lineages may explain the floristic distinctness of the fynbos flora and implies a reduced scope for edaphically driven ecological speciation.

  9. Evidence of population resistance to extreme low flows in a fluvial-dependent fish species

    Science.gov (United States)

    Katz, Rachel A.; Freeman, Mary C.

    2015-01-01

    Extreme low streamflows are natural disturbances to aquatic populations. Species in naturally intermittent streams display adaptations that enhance persistence during extreme events; however, the fate of populations in perennial streams during unprecedented low-flow periods is not well-understood. Biota requiring swift-flowing habitats may be especially vulnerable to flow reductions. We estimated the abundance and local survival of a native fluvial-dependent fish species (Etheostoma inscriptum) across 5 years encompassing historic low flows in a sixth-order southeastern USA perennial river. Based on capturemark-recapture data, the study shoal may have acted as a refuge during severe drought, with increased young-of-the-year (YOY) recruitment and occasionally high adult immigration. Contrary to expectations, summer and autumn survival rates (30 days) were not strongly depressed during low-flow periods, despite 25%-80% reductions in monthly discharge. Instead, YOY survival increased with lower minimum discharge and in response to small rain events that increased low-flow variability. Age-1+ fish showed the opposite pattern, with survival decreasing in response to increasing low-flow variability. Results from this population dynamics study of a small fish in a perennial river suggest that fluvial-dependent species can be resistant to extreme flow reductions through enhanced YOY recruitment and high survival

  10. SHIELD: The Star Formation Law in Extremely Low-mass Galaxies

    Science.gov (United States)

    Teich, Yaron; McNichols, Andrew; Cannon, John M.; SHIELD Team

    2016-01-01

    The "Survey of HI in Extremely Low-mass Dwarfs" (SHIELD) is a multiwavelength, legacy-class observational study of 12 low-mass dwarf galaxies discovered in Arecibo Legacy Fast ALFA (ALFALFA) survey data products. Here we analyze the relationships between HI and star formation in these systems using multi-configuration, high spatial (~300 pc) and spectral (0.82 - 2.46 km s-1 ch-1) resolution HI observations from the Karl G. Jansky Very Large Array, Hα imaging from the WIYN 3.5m telescope, and archival GALEX far-ultraviolet imaging. We compare the locations and intensities of star formation with the properties of the neutral ISM. We quantify the degree of local co-spatiality between star forming regions and regions of high HI column densities using the Kennicutt-Schmidt (K-S) relation. The values of the K-S index N vary considerably from system to system; because no single galaxy is representative of the sample, we instead focus on the narratives of the individual galaxies and their complex distribution of gaseous and stellar components. At the extremely faint end of the HI mass function, these systems are dominated by stochastic fluctuations in their interstellar media, which governs whether or not they show signs of recent star formation.Support for this work was provided by NSF grant AST-1211683 to JMC at Macalester College.

  11. Peritoneal drainage does not stabilize extremely low birth weight infants with perforated bowel: data from the NET Trial.

    Science.gov (United States)

    Rees, Clare M; Eaton, Simon; Khoo, A Kate; Kiely, Edward M; Pierro, Agostino

    2010-02-01

    Proponents of peritoneal drainage (PD) hypothesize that it allows stabilization before laparotomy. We examined this hypothesis by comparing clinical status before and after either PD or primary laparotomy (LAP). In an ethically approved, international, prospective randomized controlled trial (2002-2006), extremely low birth weight (drainage does not immediately improve clinical status in extremely low birth weight infants with bowel perforation. The use of PD as a stabilizing or temporizing measure is not supported by these results. Copyright 2010 Elsevier Inc. All rights reserved.

  12. Cardiovascular mortality and exposure to extremely low frequency magnetic fields: a cohort study of Swiss railway workers

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    Pfluger Dominik

    2008-07-01

    Full Text Available Abstract Background Exposure to intermittent magnetic fields of 16 Hz has been shown to reduce heart rate variability, and decreased heart rate variability predicts cardiovascular mortality. We examined mortality from cardiovascular causes in railway workers exposed to varying degrees to intermittent 16.7 Hz magnetic fields. Methods We studied a cohort of 20,141 Swiss railway employees between 1972 and 2002, including highly exposed train drivers (median lifetime exposure 120.5 μT-years, and less or little exposed shunting yard engineers (42.1 μT-years, train attendants (13.3 μT-years and station masters (5.7 μT-years. During 464,129 person-years of follow up, 5,413 deaths were recorded and 3,594 deaths were attributed to cardio-vascular diseases. We analyzed data using Cox proportional hazards models. Results For all cardiovascular mortality the hazard ratio compared to station masters was 0.99 (95%CI: 0.91, 1.08 in train drivers, 1.13 (95%CI: 0.98, 1.30 in shunting yard engineers, and 1.09 (95%CI: 1.00, 1.19 in train attendants.Corresponding hazard ratios for arrhythmia related deaths were 1.04 (95%CI: 0.68, 1.59, 0.58 (95%CI: 0.24, 1.37 and 1.30 (95%CI: 0.87, 1.93 and for acute myocardial infarction 1.00 (95%CI: 0.73, 1.36, 1.56 (95%CI: 1.04, 2.32, and 1.14 (95%CI: 0.85, 1.53. The hazard ratio for arrhythmia related deaths per 100 μT-years of cumulative exposure was 0.94 (95%CI: 0.71, 1.24 and 0.91 (95%CI: 0.75, 1.11 for acute myocardial infarction. Conclusion This study provides evidence against an association between long-term occupational exposure to intermittent 16.7 Hz magnetic fields and cardiovascular mortality.

  13. Extremely low-frequency magnetic fields and childhood acute lymphoblastic leukemia: an exploratory analysis of alternative exposure metrics.

    Science.gov (United States)

    Auvinen, A; Linet, M S; Hatch, E E; Kleinerman, R A; Robison, L L; Kaune, W T; Misakian, M; Niwa, S; Wacholder, S; Tarone, R E

    2000-07-01

    Data collected by the National Cancer Institute-Children's Cancer Group were utilized to explore various metrics of magnetic field levels and risk of acute lymphoblastic leukemia (ALL) in children. Cases were aged 0-14 years, were diagnosed with ALL during 1989-1993, were registered with the Children's Cancer Group, and resided in one home for at least 70 percent of the 5 years immediately prior to diagnosis. Controls were identified by using random digit dialing and met the same residential requirements. With 30-second ("spot") measurements and components of the 24-hour measurement obtained in the subject's bedroom, metrics evaluated included measures of central tendency, peak exposures, threshold values, and measures of short-term temporal variability. Measures of central tendency and the threshold measures showed good-to-high correlation, but these metrics correlated less well with the others. Small increases in risk (ranging from 1.02 to 1.69 for subjects in the highest exposure category) were associated with some measures of central tendency, but peak exposures, threshold values, measures of short-term variability, and spot measurements demonstrated little association with risk of childhood ALL. In general, risk estimates were slightly higher for the nighttime (10 p.m.-6 a.m.) interval than for the corresponding 24-hour period.

  14. Novel model systems for in vitro neurotoxicity testing : Chemical stressors and neurotoxic hazard of extremely low frequency electromagnetic fields

    NARCIS (Netherlands)

    de Groot, M.W.G.D.M.

    2016-01-01

    Both structurally and functionally, the nervous system is one of the most complex organ systems. Its main function is to send and receive signals; so-called neurotransmission, which largely depends on the viability and structure of neurons as well as on proper regulation of the cellular and

  15. Generation of Elf5-Cre knockin mouse strain for trophoblast-specific gene manipulation.

    Science.gov (United States)

    Kong, Shuangbo; Liang, Guixian; Tu, Zhaowei; Chen, Dunjin; Wang, Haibin; Lu, Jinhua

    2018-04-01

    Placental development is a complex and highly controlled process during which trophoblast stem cells differentiate to various trophoblast subtypes. The early embryonic death of systemic gene knockout models hampers the investigation of these genes that might play important roles during placentation. A trophoblast specific Cre mouse model would be of great help for dissecting out the potential roles of these genes during placental development. For this purpose, we generate a transgenic mouse with the Cre recombinase inserted into the endogenous locus of Elf5 gene that is expressed specifically in placental trophoblast cells. To analyze the specificity and efficiency of Cre recombinase activity in Elf5-Cre mice, we mated Elf5-Cre mice with Rosa26 mT/mG reporter mice, and found that Elf5-Cre transgene is expressed specifically in the trophoectoderm as early as embryonic day 4.5 (E4.5). By E12.5, the activity of Elf5-Cre transgene was detected exclusively in all derivatives of trophoblast lineages, including spongiotrophoblast, giant cells, and labyrinth trophoblasts. In addition, Elf5-Cre transgene was also active during spermatogenesis, from spermatids to mature sperms, which is consistent with the endogenous Elf5 expression in testis. Collectively, our results provide a unique tool to delete specific genes selectively and efficiently in trophoblast lineage during placentation. © 2018 Wiley Periodicals, Inc.

  16. Immune-Modulating Perspectives for Low Frequency Electromagnetic Fields in Innate Immunity

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    Maria Manuela Rosado

    2018-03-01

    Full Text Available In recent years, the effects of electromagnetic fields (EMFs on the immune system have received a considerable interest, not only to investigate possible negative health impact but also to explore the possibility to favorably modulate immune responses. To generate beneficial responses, the immune system should eradicate pathogens while “respecting” the organism and tolerating irrelevant antigens. According to the current view, damage-associated molecules released by infected or injured cells, or secreted by innate immune cells generate danger signals activating an immune response. These signals are also relevant to the subsequent activation of homeostatic mechanisms that control the immune response in pro- or anti-inflammatory reactions, a feature that allows modulation by therapeutic treatments. In the present review, we describe and discuss the effects of extremely low frequency (ELF-EMF and pulsed EMF on cell signals and factors relevant to the activation of danger signals and innate immunity cells. By discussing the EMF modulating effects on cell functions, we envisage the use of EMF as a therapeutic agent to regulate immune responses associated with wound healing.

  17. Characteristics of episodes with extremely low ozone values in the northern middle latitudes 1957−2000

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    D. S. Balis

    Full Text Available A number of episodes are observed when the total ozone for 2 to 3 days has fallen below 220 matm-cm in the northern mid- and polar latitudes in autumn. The occurrences of such episodes represent ozone deviations of about one-third from the pre-1976 Oct-Nov-Dec monthly mean! By using primarily quality checked Dobson data, a clear identification was made of more than three dozen short spells with extremely low ozone in the 1957–1978 period. In the following twenty-two years (1979–2000, using mainly TOMS data, one can identify ~ 46 cases with ozone values falling below 220 matm-cm for longer than 1 day, with each time over an area greater than 500,000 km2 . The Ozone Mass Deficiency (O3MD from the pre-1976 average ozone values over the affected area was ~2.8 Mt per day, i.e. four to seven times greater than it would be, assuming only a long-term trend in the Oct-Nov-Dec period. The Extremely Low Ozone (ELO3 events on the day of their appearance over the N. Atlantic/European region contribute to the O3MD by representing 16% of the deficiency due to the Oct-Nov trend in the entire 40–65° N latitudinal belt. The O3MD of the greater pool with low ozone (here taken as <260 matm-cm surrounding the area of the lowest events could contribute on the day of their appearance in Oct-Nov up to 60% and in December, ~30% to the deficiency due to the trend over the entire 40–65° N belt. Analysis of synoptic charts, supported by a backward trajectory on the isentropic surfaces 350 and 380 K, shows that in most of the events, subtropical air masses with low ozone content were transported from the Atlantic toward the UK, Scandinavia, and in many cases, further to the western sub-polar regions of Russia. This transport was sometimes combined with upward motions above a tropospheric anticyclone which lifted low ozone mixing ratios to higher altitudes. The ELO3 events cause a significant deficiency above the tropopause where, in general, the subtropical air is

  18. Exposure to overprotective parenting and psychopathology in extremely low birth weight survivors.

    Science.gov (United States)

    Day, K L; Dobson, K G; Schmidt, L A; Ferro, M A; Saigal, S; Boyle, M H; Van Lieshout, R J

    2018-03-01

    Extremely low birth weight (ELBW; overprotective (i.e., controlling and intrusive) parenting, which is hypothesized to contribute to the risk for mental disorders. Despite the increased risk for anxiety disorders and decreased risk for alcohol or substance use disorders seen in ELBW survivors, no research has examined the impact of parenting. This study investigated if overprotective parenting mediates links between ELBW birth status and psychiatric disorders in adulthood. Participants included ELBW survivors born in 1977-1982 and matched normal birth weight (≥2,500 g) control participants (ELBW n = 81; normal birth weight n = 87) prospectively followed in Ontario, Canada. These individuals retrospectively reported on whether either of their parents was overprotective using the Parental Bonding Instrument. Presence of a current anxiety disorder and of current alcohol or substance use disorders was assessed using the Mini International Neuropsychiatric Interview at age 29-36 years. Path analysis showed that overprotective parenting was a significant mediator of the association between ELBW status and risk for an anxiety disorder in adulthood and the risk for an alcohol or substance use disorder in adulthood in ELBW survivors. Overprotective parenting accounted for 53% of the association between ELBW status and the risk for an anxiety disorder in adulthood and 26% of the association between ELBW status and alcohol or substance use disorders. Overprotective parenting accounted for a substantial proportion of the increased risk for anxiety and alcohol or substance use disorders in adulthood in ELBW survivors. Despite their perceived vulnerabilities, it is important that the parents of ELBW survivors be supported in their attempts to facilitate their children's pursuit of independence during childhood and beyond. © 2017 John Wiley & Sons Ltd.

  19. Early docosahexaenoic and arachidonic acid supplementation in extremely-low-birth-weight infants.

    Science.gov (United States)

    Robinson, Daniel T; Caplan, Michael; Carlson, Susan E; Yoder, Rachel; Murthy, Karna; Frost, Brandy

    2016-10-01

    Extremely-low-birth-weight (ELBW) infants accrue large deficits in docosahexaenoic acid (DHA) and arachidonic acid (ARA) and require improved supplementation strategies. We hypothesized that once daily DHA+ARA drops applied to buccal mucosa will increase blood levels. Thirty ELBW infants were randomized to receive DHA 20 mg/kg/d + ARA 40 or 60 mg/kg/d + ARA 120 mg/kg/d or placebo within 72 h of age for 8 wk duration. Red blood cell phospholipid levels of DHA (primary) and ARA (secondary) were measured at 2 and 8 wk of age. Twenty-eight survivors with a median birth weight of 806 g completed dosing and sampling. Red blood cell levels were similar between the three groups at 2 wk (DHA: 4.62 wt% (interquartile range (IQR) 4.1-5.5) for all, P = 0.29 between groups; ARA: 21.1 wt% (IQR 18.78-22.6) for all, P = 0.41 between groups) and 8 wk (DHA: 6.0 wt% (IQR 5.1-7.1) for all, P = 0.57 between groups; ARA: 20.1 wt% (IQR 18.3-23.1) for all, P = 0.63 between groups). DHA in all infants showed a median increase of 31% from 2 to 8 wk (P 0.6). Daily buccal DHA and ARA supplements did not affect fatty acid levels in ELBW infants.

  20. Early-Onset Invasive Candidiasis in Extremely Low Birth Weight Infants: Perinatal Acquisition Predicts Poor Outcome.

    Science.gov (United States)

    Barton, Michelle; Shen, Alex; O'Brien, Karel; Robinson, Joan L; Davies, H Dele; Simpson, Kim; Asztalos, Elizabeth; Langley, Joanne; Le Saux, Nicole; Sauve, Reginald; Synnes, Anne; Tan, Ben; de Repentigny, Louis; Rubin, Earl; Hui, Chuck; Kovacs, Lajos; Yau, Yvonne C W; Richardson, Susan E

    2017-04-01

    Neonatal invasive candidiasis (IC) presenting in the first week of life is less common and less well described than later-onset IC. Risk factors, clinical features, and disease outcomes have not been studied in early-onset disease (EOD, ≤7 days) or compared to late-onset disease (LOD, >7 days). All extremely low birth weight (ELBW, candidiasis enrolled from 2001 to 2003 were included in this study. Factors associated with occurrence and outcome of EOD in ELBW infants were determined. Forty-five ELBW infants and their 84 matched controls were included. Fourteen (31%) ELBW infants had EOD. Birth weight <750 g, gestation <25 weeks, chorioamnionitis, and vaginal delivery were all strongly associated with EOD. Infection with Candida albicans, disseminated disease, pneumonia, and cardiovascular disease were significantly more common in EOD than in LOD. The EOD case fatality rate (71%) was higher than in LOD (32%) or controls (15%) (P = .0001). The rate of neurodevelopmental impairment and mortality combined was similar in EOD (86%) and LOD (72%), but higher than in controls (32%; P = .007). ELBW infants with EOD have a very poor prognosis compared to those with LOD. The role of perinatal transmission in EOD is supported by its association with chorioamnionitis, vaginal delivery, and pneumonia. Dissemination and cardiovascular involvement are common, and affected infants often die. Empiric treatment should be considered for ELBW infants delivered vaginally who have pneumonia and whose mothers have chorioamnionitis or an intrauterine foreign body. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  1. Permissive hypotension in the extremely low birthweight infant with signs of good perfusion.

    LENUS (Irish Health Repository)

    Dempsey, E M

    2012-01-31

    INTRODUCTION: Many practitioners routinely treat infants whose mean arterial blood pressure in mm Hg is less than their gestational age in weeks (GA). OBJECTIVE: To assess the effectiveness of utilising a combined approach of clinical signs, metabolic acidosis and absolute blood pressure (BP) values when deciding to treat hypotension in the extremely low birthweight (ELBW) infant. METHODS: Retrospective cohort study of all live born ELBW infants admitted to our neonatal intensive care unit over a 4-year period. Patients were grouped as either normotensive (BP never less than GA), hypotensive and not treated (BP

  2. Socioeconomic Attainment of Extremely Low Birth Weight Survivors: The Role of Early Cognition.

    Science.gov (United States)

    Dobson, Kathleen G; Ferro, Mark A; Boyle, Michael H; Schmidt, Louis A; Saigal, Saroj; Van Lieshout, Ryan J

    2017-03-01

    To determine: (1) if childhood cognitive and academic abilities mediate the association between being born at extremely low birth weight (ELBW) and socioeconomic attainment at age 29 to 36 years; (2) which cognitive abilities (IQ, verbal abilities, fluid intelligence, mathematical abilities, or academic achievement) most strongly mediate this association; and (3) if the mediating role of cognition is different in ELBW survivors with significant neurosensory impairment (NSI). A prospective, longitudinal cohort of 100 Canadian ELBW survivors born between 1977 and 1982 and 89 normal birth weight comparison participants were used to examine the mediating role of childhood cognition by using 5 cognitive mediators assessed at age 8 years (overall IQ, verbal IQ, performance IQ, quantitative ability, and academic achievement) on socioeconomic attainment at adulthood. Socioeconomic attainment was defined as personal annual earnings and full-time employment assessed via self-report at age 29 to 36 years. Mediation models revealed that childhood cognition mediated the association between ELBW status and income attainment, with mathematical abilities and overall IQ each accounting for 26% of the direct effect. Mediated effects were not statistically significant in full-time employment models. For both outcomes, the mediating effect of cognition was stronger for ELBW survivors with NSI. Childhood cognitive abilities partially mediate associations between ELBW status and adult income attainment. Early life cognition is a critical predictor of socioeconomic attainment in ELBW survivors, particularly in those born with NSI. Interventions aimed at enhancing early cognition in ELBW survivors may help optimize their later socioeconomic attainment. Copyright © 2017 by the American Academy of Pediatrics.

  3. THE ELM SURVEY. I. A COMPLETE SAMPLE OF EXTREMELY LOW-MASS WHITE DWARFS

    International Nuclear Information System (INIS)

    Brown, Warren R.; Kilic, Mukremin; Kenyon, Scott J.; Prieto, Carlos Allende

    2010-01-01

    We analyze radial velocity observations of the 12 extremely low-mass (ELM), with ≤0.25 M sun , white dwarfs (WDs) in the MMT Hypervelocity Star Survey. Eleven of the twelve WDs are binaries with orbital periods shorter than 14 hr; the one non-variable WD is possibly a pole-on system among our non-kinematically selected targets. Our sample is unique: it is complete in a well-defined range of apparent magnitude and color. The orbital mass functions imply that the unseen companions are most likely other WDs, although neutron star companions cannot be excluded. Six of the eleven systems with orbital solutions will merge within a Hubble time due to the loss of angular momentum through gravitational wave radiation. The quickest merger is J0923+3028, a g = 15.7 ELM WD binary with a 1.08 hr orbital period and a ≤130 Myr merger time. The chance of a supernova Ia event among our ELM WDs is only 1%-7%, however. Three binary systems (J0755+4906, J1233+1602, and J2119-0018) have extreme mass ratios and will most likely form stable mass-transfer AM CVn systems. Two of these objects, SDSS J1233+1602 and J2119-0018, are the lowest surface gravity WDs ever found; both show Ca II absorption likely from accretion of circumbinary material. We predict that at least one of our WDs is an eclipsing detached double WD system, important for constraining helium core WD models.

  4. Choice of optimal working fluid for binary power plants at extremely low temperature brine

    Science.gov (United States)

    Tomarov, G. V.; Shipkov, A. A.; Sorokina, E. V.

    2016-12-01

    The geothermal energy development problems based on using binary power plants utilizing lowpotential geothermal resources are considered. It is shown that one of the possible ways of increasing the efficiency of heat utilization of geothermal brine in a wide temperature range is the use of multistage power systems with series-connected binary power plants based on incremental primary energy conversion. Some practically significant results of design-analytical investigations of physicochemical properties of various organic substances and their influence on the main parameters of the flowsheet and the technical and operational characteristics of heat-mechanical and heat-exchange equipment for binary power plant operating on extremely-low temperature geothermal brine (70°C) are presented. The calculation results of geothermal brine specific flow rate, capacity (net), and other operation characteristics of binary power plants with the capacity of 2.5 MW at using various organic substances are a practical interest. It is shown that the working fluid selection significantly influences on the parameters of the flowsheet and the operational characteristics of the binary power plant, and the problem of selection of working fluid is in the search for compromise based on the priorities in the field of efficiency, safety, and ecology criteria of a binary power plant. It is proposed in the investigations on the working fluid selection of the binary plant to use the plotting method of multiaxis complex diagrams of relative parameters and characteristic of binary power plants. Some examples of plotting and analyzing these diagrams intended to choose the working fluid provided that the efficiency of geothermal brine is taken as main priority.

  5. Prospective Analysis of Pulmonary Hypertension in Extremely Low Birth Weight Infants

    Science.gov (United States)

    Bhat, Ramachandra; Salas, Ariel A.; Foster, Chris; Carlo, Waldemar A.

    2012-01-01

    OBJECTIVES: Pulmonary hypertension is associated with bronchopulmonary dysplasia in extremely low birth weight (ELBW) infants and contributes to morbidity and mortality. The objective was to determine the prevalence of pulmonary hypertension among ELBW infants by screening echocardiography and evaluate subsequent outcomes. METHODS: All ELBW infants admitted to a regional perinatal center were evaluated for pulmonary hypertension with echocardiography at 4 weeks of age and subsequently if clinical signs suggestive of right-sided heart failure or severe lung disease were evident. Management was at discretion of the clinician, and infants were evaluated until discharge from the hospital or pre-discharge death occurred. RESULTS: One hundred forty-five ELBW infants (birth weight: 755 ± 144 g; median gestational age: 26 weeks [interquartile range: 24–27]) were screened from December 2008 to February 2011. Overall, 26 (17.9%) were diagnosed with pulmonary hypertension at any time during hospitalization (birth weight: 665 ± 140 g; median gestational age: 26 weeks [interquartile range: 24–27]): 9 (6.2%) by initial screening (early pulmonary hypertension) and 17 (11.7%) who were identified later (late pulmonary hypertension). Infants with pulmonary hypertension were more likely to receive oxygen treatment on day 28 compared with those without pulmonary hypertension (96% vs 75%, P Pulmonary hypertension is relatively common, affecting at least 1 in 6 ELBW infants, and persists to discharge in most survivors. Routine screening of ELBW infants with echocardiography at 4 weeks of age identifies only one-third of the infants diagnosed with pulmonary hypertension. Further research is required to determine optimal detection and intervention strategies. PMID:22311993

  6. Early corticosteroid treatment does not affect severity of unconjugated hyperbilirubinemia in extreme low birth weight preterm infants

    NARCIS (Netherlands)

    Hulzebos, Christian V.; Bos, Arend F.; Anttila, Eija; Hallman, Mikko; Verkade, Henkjan J.

    Aim: To determine the relationship between early postnatal dexamethasone (DXM) treatment and the severity of hyperbilirubinemia in extreme low birth weight (ELBW) preterm infants. Methods: In 54 ELBW preterm infants, total serum bilirubin concentrations (TSB) and phototherapy (PT) data during the

  7. Gluconeogenesis is not regulated by either glucose or insulin in extremely low birth weight infants receiving total parenteral nutrition

    Science.gov (United States)

    The objective was to determine potential factors regulating gluconeogenesis (GNG) in extremely low birth weight infants receiving total parenteral nutrition. Seven infants (birth weight, 0.824 +/- 0.068 kg; gestational age, 25.4 +/- 0.5 weeks; postnatal age, 3.3 +/- 0.2 days) were studied for 11 hou...

  8. Noise and light exposures for extremely low birth weight newborns during their stay in the neonatal intensive care unit.

    Science.gov (United States)

    Lasky, Robert E; Williams, Amber L

    2009-02-01

    The objectives of this study were to characterize noise and light levels for extremely low birth weight newborns throughout their stay in the NICU, evaluate factors influencing noise and light levels, and determine whether exposures meet recommendations from the American Academy of Pediatrics. Sound and light were measured inside the beds of extremely low birth weight newborns (n = 22) from birth to discharge. Measurements were recorded for 20 consecutive hours weekly from birth until 36 weeks' postmenstrual age, biweekly until 40 weeks, and every 4 weeks thereafter. Clinical variables including bed type and method of respiratory support were recorded at each session. Age-related changes in respiratory support and bed type explained the weekly increase of 0.22 dB in sound level and 3.67 lux in light level. Old incubators were the noisiest bed types, and new incubators were the quietest. Light levels were significantly higher in open beds than in incubators. The variations in noise and light levels over time were greatest for open beds. Noise and light levels were much less affected by respiratory support in incubators compared with open beds. A typical extremely low birth weight neonate was exposed to noise levels averaging 56.44 dB(A) and light levels averaging 70.56 lux during their stay from 26 to 42 weeks' postmenstrual age in the NICU. Noise levels were rarely within American Academy of Pediatrics recommendations (5.51% of the time), whereas light levels almost always met recommendations (99.37% of the time). Bed type and respiratory support explained differences in noise and light levels that extremely low birth weight newborns experience during their hospital stay. Noise levels exceeded recommendations, although evidence supporting those recommendations is lacking. Well-designed intervention studies are needed to determine the effects of noise reduction on the development of extremely low birth weight newborns.

  9. Ultrastructural Study on Ultra-Low Frequency Electromagnetic Fields and Transfer Factor Effects on Skin Ulcers

    International Nuclear Information System (INIS)

    Cadena, M. S. Reyes; Chapul, L. Sanchez; Perez, Javier; Garcia, M. N. Jimenez; Lopez, M. A. Jimenez; Espindola, M. E. Sanchez; Perez, R. Paniagua; Hernandez, N. A.; Paniagua, G.; Uribe, F.; Nava, J. J. Godina; Segura, M. A. Rodriguez

    2008-01-01

    We determined the effect of 120Hz ultra low frequency electromagnetic field (ELF) on the healing process of skin in 20 Wistar rats distributed in four groups in which chronic dermal ulcers had been produced. The first two groups received a dose of the transfer factor and interferon-beta (IFN-β) every 24 h during 12 days. The third group (positive control) received only electromagnetic field (ELF) sessions, and in the fourth group (negative control), no treatment was applied. The electromagnetic field was applied through a Helmholtz coils; 30 Gauss of intensity. Results shown histological changes that improve the healing process in animals subjected to ELF together with the transfer factor

  10. Anaphora in question-answer sessions in university ELF contexts.

    Directory of Open Access Journals (Sweden)

    Thomas Wulstan Christiansen

    2015-07-01

    Full Text Available Abstract - Identity chains (Hasan 1984 ˗ strings of co-referential noun phrases ˗ constitute a lesser researched area in the field of ELF, as has the more general area of cohesion (but see Hüttner 2009, Christiansen 2011. Following on the work on anaphora of such scholars as Reinhart (1983 and Cornish (1999, and on cohesion (e.g. Halliday and Hasan 1976, Halliday 2004, Christiansen (2009a/b, 2011 focuses on the link between text cohesion and discourse coherence. The interactive perspective of discourse (seen as the process of which text is the product: see Widdowson 1984: 100 is especially relevant to an ELF context of spontaneous spoken interaction. As Guido (2008 evidences, different inter-cultural concerns constitute a crucial dimension to the complex multi-code interaction. Consequently, the diverse ways in which speakers from different L1 backgrounds employ anaphors and construct identity chains are key elements in the co-construction of a dialogic text. In this case study, six extracts of transcripts taken from the VOICE corpus (2011 of conference question and answer sessions set in multicultural contexts are analysed qualitatively. The different ways that participants construct identity chains (e.g. whether they use full forms of various kinds or anaphoric pro-forms are classified. The analysis focuses on both how individual anaphors are resolved and how relations between anaphors and antecedent triggers are encoded, and how identity chains are constructed and organized individually. The objective is to identify which kinds of noun phrase (various subtypes of full and pro-forms are used by diverse groups of EFL speakers both in relation to their own contributions and to those of other speakers (with a threefold distinction made between the same turn of the same speaker, a different turn of the same speaker, and a different turn by a different speaker.

  11. Excitation of the Magnetospheric Cavity by Space-Based ELF/VLF Transmitters

    National Research Council Canada - National Science Library

    Bell, Timothy F; Inan, Umran; Kulkarni, P

    2004-01-01

    During the period of performance Stanford University: 1. Developed an analytical model describing the distribution of current along a dipole antenna radiating ELF/VLF waves in the magnetospheric cavity...

  12. Changes in mortality for extremely low birth weight infants in the 1990s: implications for treatment decisions and resource use.

    Science.gov (United States)

    Meadow, William; Lee, Grace; Lin, Kathy; Lantos, John

    2004-05-01

    Much has changed in neonatal intensive care unit (NICU) care over the past decade. High-frequency oscillation, inhaled nitric oxide, and antenatal corticosteroids are now widely available. We wondered how these medical advances had affected both the epidemiology and ethics of life and death for extremely low birth weight (ELBW) infants in the NICU. We identified 1142 ELBW infants (birth weight [BW] NICU between 1991 and 2001. We abstracted BW, gestational age, survival or death, and length of stay in the NICU. Statistical analyses were performed by using linear regression and 2-way analysis of variance. Both increasing BW and later year were significantly associated with improved survival. However, for larger ELBW infants, survival was approximately 90% for the entire decade, and large-scale improvement was hardly possible. For smaller infants, greater improvements were both possible and observed, at least early in the decade. From 1991 to 1997, overall ELBW survival increased steadily (approximately 4% per year). However, from 1997 to 2001, there was no significant improvement in survival for ELBW infants. There was no change in the distribution of deaths accounted for by BW subgroups within the ELBW population from 1991 to 2001. Median length of stay for infants who eventually expired before discharge rose from 2 days in 1991 to 10 days in 2001. As a consequence, during the past decade, the percentage of infants whose outcome was "undeclared" by day of life 4 rose from 10% to 20% for ELBW infants overall and to 33% for infants with BWs of 450 to 700 g. The percentage of ELBW NICU bed-days occupied by nonsurvivors remained very low (approximately 7%) from 1991 to 2001. 1) Fewer infants in all ELBW subgroups are dying, compared with a decade ago, and the improvement has been most prominent for BWs of 450 to 700 g, at which mortality was and remains to be greatest. 2) This progress seems to have slowed, or even stopped, by the end of the decade. 3) Although most

  13. Chorioamnionitis and lung damage in the extremely low birth weight infant

    Directory of Open Access Journals (Sweden)

    Gustavo Rocha

    2007-09-01

    Full Text Available Some experimental work suggests that exposure to intrauterine infection is associated, not only, with lung maturation and a reduced risk of respiratory distress syndrome, but also, with delayed alveolarization and increased risk of bronchopulmonary dysplasia. Aim: To evaluate the association between histological chorioamnionitis and lung disease in extremely low birth weight preterm infants. Methods: A retrospective chart review of 63 less than 1000 g birthweight, appropriated for gestational age neonates, delivered at three tertiary medical centers in the north of Portugal, between 2001 and 2002. The association between histological chorioamnionitis and lung damage (respiratory distress syndrome and bronchopulmonary dysplasia was evaluated through the calculation of crude and adjusted odds ratio. Results: There were 32 newborns from mothers with histological chorioamnionitis and 31 without the condition. The association between histological chorioamnionitis and respiratory distress syndrome was OR 0.23 (95% CI 0.01 – 2.51. The association between chorioamnionitis and bronchopulmonary dysplasia was OR 1.61 (95% CI 0.38 – 6.97. The association between histological chorioamnionitis and bronchopulmonary dysplasia when adjusted for gestational age, multiple birth and C-section revealed no statistical significance: OR 2.66 (95% CI 0.36 – 19.60 for chorioamnionitis without funisitis or vasculitis and OR 1.68 (95% CI 0.25 – 11.18 for funisitis and/or vasculitis. Conclusion: In this study we could not confirm a decreased risk of respiratory distress syndrome nor an increased risk of bronchopulmonary dysplasia in extremely low birth weight preterm neonates with histological chorioamnionitis. Resumo: Alguns estudos experimentais sugerem que a exposição a infecção intra-uterina associa-se, não só, a maturação pulmonar e menor risco de doença das membranas hialinas, mas também a atraso na forma

  14. ULF-ELF Electromagnetic Emissions Over the Fault in Kangra Valley of India and their Relation With Radon Emanation (Intercosmos 24 Satellite Data)

    International Nuclear Information System (INIS)

    Mikhailov, Yu.M.; Mikhailova, G.A.; Kapustina, O.V.

    1999-01-01

    Experimental investigations of space and spectral characteristics of the electric component of the electromagnetic waves in the outer ionosphere in the ULF (f < 30 Hz) and ELF (f < 1 kHz) ranges were carried out over north fault of the India - Australian plate. Records of the 10 narrow band filters in the frequency range from 8 to 970 Hz with NVK-receiver mounting on Intercosmos 24 satellite were used. In the day-time at sensitivity level near 2 μV/m emissions couldn't observe. In the night-time emissions, localized exactly in space above the fault, was observed in mentioned full frequency range. In spectral distribution of emission maximum in frequency range from 150 to 623 Hz allocated. In those days, when anomalous bursts of radon concentration in underground waters in Kangra Valley was observed the simultaneous amplification of electric component of field at frequency 8 Hz more on the factor more than ten and in frequency range from 150 to 623 Hz, where usually was maximum, on the factor two or three also was observed. This fact ensures statement, that the noises are generated by the lightning discharges, but amplification of their intensity on satellite heights was related with decreasing of ELF waves attenuation in the time of their penetration through lower ionosphere, modified by electric field in preparing phase of the earthquakes. (author)

  15. Phosphorylation of protein synthesis initiation factor 2 (elF-2) in the yeast Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Romero, D.P.

    1986-01-01

    Initiation Factor 2 (elF-2) in the yeast Saccharomyces cerevisiae is comprised of 3 subunits. The control of protein synthesis in mammalian cells have been shown to involve the phosphorylation of the small (alpha) subunit by a specific protein kinase. Phosphorylation results in an inhibition of protein synthesis. In order to determine whether or not an analogous system is operative in yeast, the phosphorylation state of the alpha subunit of elF-2 in Saccharomyces was determined during various growth and nongrowth conditions. Cells were radiolabelled with 32 P and 35 S, and the whole cell lysates were analyzed by two dimensional gel electrophoresis. These experiments revealed that the smallest subunit (alpha, M/sub r/ = 31,000) is a phosphoprotein in vivo under a variety of growth and nongrowth conditions. This is in direct contrast to the pattern exhibited in mammalian cells. The fact that the small subunit of elF-2 in yeast is phosphorylated under a variety of physiological conditions indicates that such a covalent modification is important for some aspects of elF-2 function. In order to investigate this problem further, a protein kinase that specifically labels the alpha subunit of elF-2 in vitro was isolated. The kinase is not autophosphorylating, utilizes ATP as a phosphate donor, phosphorylates an exogenous protein, casein, modifies serine residues in elF-2, is cyclic nucleotide-independent, and is strongly inhibited by heparin

  16. DNA micro array analysis of yeast global genome expression in response to ELF-MF exposure

    International Nuclear Information System (INIS)

    Shimizu, K.; Yamamoto, T.; Ishibashi, T.; Kyoh, B.

    2002-01-01

    There is wide spread public concern over the possible health risk of ELF-MF. Electromagnetic fields may produce a variety of effects in several biological systems, including the elevation of cancer risk and reduction of cell growth. Epidemiological studies have shown weak correlations between the exposure to ELF and the incidence of several cancers, but negative studies have also been reported. Moreover, there are some reports that basic biological events such as the cell cycle and DNA replication were affected by exposure to MF. However, to date the molecular mechanism of the MF effect on living organism is not clear. In this study, we used yeast DNA micro array to examine the transcriptional profile of all genes in response to ELF-MF. A few years ago it was difficult to carry out a global gene expression study to identify important genes regarding ELF-MF, however, today DNA micro arrays allow gene regulation in response to high density ELF-MF exposure. Thus we used micro array to analyze changes in mRNA abundance during ELF-MF exposure

  17. ELF-VLF communications through the Earth Project report for calendar year 1984, revision 1

    Science.gov (United States)

    Buettner, H. M.; Burker, G. J.; Didwall, E. M.; Holladay, G.; Lytle, R. J.

    1985-08-01

    We use computer models and experiments to explore the feasibility of communication between points underground and on the Earth's surface. Emphasis is placed on ELF-VLF electromagnetic propagation through the Earth; nominally, we investigated propagation in the 200 Hz-30 kHz frequency range. The computer modeling included calculations of the fields of a point electric or magnetic source in a homogeneous half space or a stratified earth. Initial results for an insulated antenna of finite length are also considered. The experiments involved through-the-Earth transmissions at two locations in Pennsylvania, both of which had large formations of limestone. Initial results indicate that information rates as high as kbits/s may be possible for subsurface depths of 300 m or less. Accuracy of these estimates depends on the electromagnetic propagation constant of the rock, the noise characteristics, and the modulation scheme. Although a nuisance for evaluating through-the-Earth propagation, the existence of subsurface metal conductors can improve the transmission character of the site.

  18. ELF-VLF Communications through the Earth Project report for calendar year 1984. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, H.M.; Burke, G.J.; Didwall, E.M.; Holladay, G.; Lytle, R.J.

    1985-08-01

    We use computer models and experiments to explore the feasibility of communication between points underground and on the Earth's surface. Emphasis is placed on ELF-VLF electromagnetic propagation through the Earth; nominally, we investigated propagation in the 200 Hz-30 kHz frequency range. The computer modeling included calculations of the fields of a point electric or magnetic source in a homogeneous half space or a stratified earth. Initial results for an insulated antenna of finite length are also considered. The experiments involved through-the-earth transmissions at two locations in Pennsylvania, both of which had large formations of limestone. Initial results indicate that information rates as high as kbits/s may be possible for subsurface depths of 300 m or less. Accuracy of these estimates depends on the electromagnetic propagation constant of the rock, the noise characteristics, and the modulation scheme. Although a nuisance for evaluating through-the-Earth propagation, the existence of subsurface metal conductors can improve the transmission character of the site.

  19. The 'Effects of Transfusion Thresholds on Neurocognitive Outcome of Extremely Low Birth-Weight Infants (ETTNO)' Study

    DEFF Research Database (Denmark)

    Reinholdt, Jes; Veiergang, Gitte

    2012-01-01

    Background: Infants with extremely low birth weight uniformly develop anemia of prematurity and frequently require red blood cell transfusions (RBCTs). Although RBCT is widely practiced, the indications remain controversial in the absence of conclusive data on the long-term effects of RBCT....... Objectives: To summarize the current equipoise and to outline the study protocol of the 'Effects of Transfusion Thresholds on Neurocognitive Outcome of extremely low birth-weight infants (ETTNO)' study. Methods: Review of the literature and design of a large pragmatic randomized controlled trial...... of restrictive versus liberal RBCT guidelines enrolling 920 infants with birth weights of 400-999 g with long-term neurodevelopmental follow-up. Results and Conclusions: The results of ETTNO will provide definite data about the efficacy and safety of restrictive versus liberal RBCT guidelines in very preterm...

  20. Comparing the asteroseismic properties of pulsating extremely low-mass pre-white dwarf stars and δ Scuti stars

    Directory of Open Access Journals (Sweden)

    Arias J.P.Sánchez

    2017-01-01

    Full Text Available We present the first results of a detailed comparison between the pulsation properties of pulsating Extremely Low-Mass pre-white dwarf stars (the pre-ELMV variable stars and δ Scuti stars. The instability domains of these very different kinds of stars nearly overlap in the log Teff vs. log g diagram, leading to a degeneracy in the classification of the stars. Our aim is to provide asteroseismic tools for their correct classification.

  1. The role of localised Ultra-Low Frequency waves in energetic electron precipitation

    Science.gov (United States)

    Rae, J.; Murphy, K. R.; Watt, C.; Mann, I. R.; Ozeke, L.; Halford, A. J.; Sibeck, D. G.; Clilverd, M. A.; Rodger, C. J.; Degeling, A. W.; Singer, H. J.

    2016-12-01

    Electromagnetic waves play pivotal roles in radiation belt dynamics through a variety of different means. Typically, Ultra-Low Frequency (ULF) waves have historically been invoked for radial diffusive transport leading to both acceleration and loss of outer radiation belt electrons. Very-Low Frequency (VLF) and Extremely-Low Frequency (ELF) waves are generally thought to provide a mechanism for localized acceleration and loss through precipitation into the ionosphere. In this study we present a new mechanism for electron loss through precipitation into the ionosphere due to direct modulation of the loss cone via localized compressional ULF waves. Observational evidence is presented demonstrating that modulation of the equatorial loss cone can occur via localized compressional wave activity. We then perform statistical computations of the probability distribution to determine how likely a given magnetic perturbation would produce a given percentage change in the bounce loss-cone (BLC). We discuss the ramifications of the action of coherent, localized compressional ULF waves on drifting electron populations; their precipitation response can be a complex interplay between electron energy, the shape of the phase space density profile at pitch angles close to the loss cone, ionospheric decay timescales, and the time-dependence of the electron source. We present a case study of compressional wave activity in tandem with riometer and balloon-borne electron precipitation across keV-MeV energies to demonstrate that the experimental measurements can be explained by our new enhanced loss cone mechanism. We determine that the two pivotal components not usually considered are localized ULF wave fields and ionospheric decay timescales. We conclude that ULF wave modulation of the loss cone is a viable candidate for direct precipitation of radiation belt electrons without any additional requirement for gyroresonant wave-particle interaction. Additional mechanisms would be

  2. Comparison of magnetic field meters used for Elf exposure measurement

    International Nuclear Information System (INIS)

    Magne, I.; Azoulay, A.; Lambrozo, J.; Souques, M.

    2006-01-01

    Objective The question of the biological effects of E.L.F. electromagnetic fields (50/60 Hz) has lead to many experimental and epidemiological works, in occupational exposure and in residential exposure. One of the main difficulties is to integrate the maximum of information about the environmental exposures during the everyday life without limitation to the exposure of the home. The objective of this study is to analyse experimentally the metrology associated with human exposure to 50 Hz magnetic field, in the optic of a study of the French population exposure. Method 4 meters were tested: the E.M.D.E.X. II, currently used in epidemiological studies, the E.M.D.E.X. L.I.T.E., which is more recent, the H.T.300, an Italian meter, and the F.D.3, which is made by Combinova A calibration was performed with an Helmoltz coil. The immunity of these meters to GSM signal was also tested. The influence of the sample rate was evaluated. Results and conclusion The meter chosen for performing the measurements of the exposure study will be selected in function of the following criteria: - easiness of use - precision - low sample rate - memory size and reliability of data stocking - immunity to GSM perturbations. (authors)

  3. Trends in survival among extremely-low-birth-weight infants (less than 1000 g without significant bronchopulmonary dysplasia

    Directory of Open Access Journals (Sweden)

    Botet Francesc

    2012-06-01

    Full Text Available Abstract Objective The aim of this study was to analyze the evolution from 1997 to 2009 of survival without significant (moderate and severe bronchopulmonary dysplasia (SWsBPD in extremely-low-birth-weight (ELBW infants and to determine the influence of changes in resuscitation, nutrition and mechanical ventilation on the survival rate. Study design In this study, 415 premature infants with birth weights below 1000 g (ELBW were divided into three chronological subgroups: 1997 to 2000 (n = 65, 2001 to 2005 (n = 178 and 2006 to 2009 (n = 172. Between 1997 and 2000, respiratory resuscitation in the delivery room was performed via a bag and mask (Ambu®, Ballerup, Sweden with 40-50% oxygen. If this procedure was not effective, oral endotracheal intubation was always performed. Pulse oximetry was never used. Starting on January 1, 2001, a change in the delivery room respiratory policy was established for ELBW infants. Oxygenation and heart rate were monitored using a pulse oximeter (Nellcor® attached to the newborn’s right hand. If resuscitation was required, ventilation was performed using a face mask, and intermittent positive pressure was controlled via a ventilator (Babylog2, Drägger. In 2001, a policy of aggressive nutrition was also initiated with the early provision of parenteral amino acids. We used standardized parenteral nutrition to feed ELBW infants during the first 12–24 hours of life. Lipids were given on the first day. The glucose concentration administered was increased by 1 mg/kg/minute each day until levels reached 8 mg/kg/minute. Enteral nutrition was started with trophic feeding of milk. In 2006, volume guarantee treatment was instituted and administered together with synchronized intermittent mandatory ventilation (SIMV + VG. The complications of prematurity were treated similarly throughout the study period. Patent ductus arteriosus was only treated when hemodynamically significant. Surgical closure of the

  4. ELF Transients and Q-bursts Detected Around the Globe: First results from Palmer Station, Antarctica

    Science.gov (United States)

    Flint, Q. A.; Moore, R. C.

    2016-12-01

    We present the first analysis of data from the recently deployed broadband ELF (5-500 Hz) B-field receiver at Palmer Station, Antarctica together with observations at similar receivers located at Sondrestromfjord, Greenland and Arrival Heights, Antarctica. Such remote locations afford the unique opportunity to record signals that are essentially unperturbed by power line noise. As a result, using this multi-site global network of ELF/VLF receivers, we are able to easily detect a particular type of ELF transient that propagates around the world multiple times, known as the Q-burst. The Q-burst is characterized by a large increase in amplitude above the background at the Schumann Resonance modes and is believed to result from especially powerful cloud-to-ground lightning discharges. These powerful lightning discharges are likely responsible for a significant level of energetic coupling between the troposphere, the ionosphere, and the magnetosphere. The ELF and VLF waves excited by the lightning discharge propagate to great distances in the earth-ionosphere waveguide, and in fact propagate around the Earth multiple times. By measuring the received waveform at multiple distant sites around the globe, we can pinpoint the source lightning location, compare the changes in field strength and spectrum as a function of distance from the source, and evaluate modal propagation effects in the VLF range (that are not apparent in the ELF range).

  5. Rationales, design and recruitment for the Elfe longitudinal study

    Directory of Open Access Journals (Sweden)

    Salines Georges

    2009-09-01

    Full Text Available Abstract Background Many factors act simultaneously in childhood to influence health status, life chances and well being, including pre-birth influences, the environmental pollutants of early life, health status but also the social influences of family and school. A cohort study is needed to disentangle these influences and explore attribution. Methods Elfe will be a nationally representative cohort of 20 000 children followed from birth to adulthood using a multidisciplinary approach. The cohort will be based on the INSEE Permanent Demographic Panel (EDP established using census data and civil records. The sample size has been defined in order to match the representativeness criteria and to obtain some prevalence estimation, but also to address the research area of low exposure/rare effects. The cohort will be based on repeated surveys by face to face or phone interview (at birth and each year as well as medical interview (at 2 years and examination (at 6 years. Furthermore, biological samples will be taken at birth to evaluate the foetal exposition to toxic substances, environmental sensors will be placed in the child's homes. Pilot studies have been initiated in 2007 (500 children with an overall acceptance rate of 55% and are currently under progress, the 2-year survey being carried out in October this year. Discussion The longitudinal study will provide a unique source of data to analyse the development of children in their environment, to study the various factors interacting throughout the life course up to adulthood and to determine the impact of childhood experience on the individual's physical, psychological, social and professional development.

  6. Conjunctions in ELF academic discourse: a corpus-based analysis

    Directory of Open Access Journals (Sweden)

    Laura Centonze

    2014-03-01

    Full Text Available Abstract – Conjunctions as fundamental elements in the construction of discourse cohesion represent a relatively neglected research area, due to their complexity and the bewildering number of “conjunctive relations” (Halliday and Hasan 1976: 226 that they may express in context, as also highlighted in Christiansen (2011. In addition to this, there does not seem to be a shared view as far as the classification and denomination of the different kinds of conjunctions are concerned (cf. Halliday and Hasan 1976; Vande Kopple 1985; Martin and Rose 2003; Hyland 2005b. The selection of a specific type of conjunction acquires more importance because they are typically open to so many different interpretations, especially when the participants in the speech event come from diverse lingua-cultural backgrounds (cf. Guido 2007; Guido 2008; Cogo et al. 2011.Following the taxonomy provided by Halliday and Hasan (1976 for conjunctions, our study attempts to shed light on the usage of conjunctions by ELF speakers in specific contexts. We shall consider ten transcripts taken from the VOICE Corpus (Seidlhofer et. al 2013, namely five interviews and five conversations in multicultural academic contexts (approximately 4,000 words each, and analyze the number of instances for each type of conjunction (additive, adversative, clausal, temporal as well as continuatives in depth, by adopting a quantitative as well as a qualitative method and by using TextSTAT 2.9 (Huning 2012. We shall then move on to the analysis of conjunctions with respect to their internal properties/collocates and eventually see the occurrence of conjunctions by comparing them with the two different speech events which are chosen as the subject of our study, i.e. interviews and conversations. We shall see the extent to which certain conjunctions are more restricted than others in terms of usage (cf. Leung 2005 in both types of speech events, despite the great number of options available to the

  7. Optimization of the Runner for Extremely Low Head Bidirectional Tidal Bulb Turbine

    Directory of Open Access Journals (Sweden)

    Yongyao Luo

    2017-06-01

    Full Text Available This paper presents a multi-objective optimization procedure for bidirectional bulb turbine runners which is completed using ANSYS Workbench. The optimization procedure is able to check many more geometries with less manual work. In the procedure, the initial blade shape is parameterized, the inlet and outlet angles (β1, β2, as well as the starting and ending wrap angles (θ1, θ2 for the five sections of the blade profile, are selected as design variables, and the optimization target is set to obtain the maximum of the overall efficiency for the ebb and flood turbine modes. For the flow analysis, the ANSYS CFX code, with a SST (Shear Stress Transport k-ω turbulence model, has been used to evaluate the efficiency of the turbine. An efficient response surface model relating the design parameters and the objective functions is obtained. The optimization strategy was used to optimize a model bulb turbine runner. Model tests were carried out to validate the final designs and the design procedure. For the four-bladed turbine, the efficiency improvement is 5.5% in the ebb operation direction, and 2.9% in the flood operation direction, as well as 4.3% and 4.5% for the three-bladed turbine. Numerical simulations were then performed to analyze the pressure pulsation in the pressure and suction sides of the blade for the prototype turbine with optimal four-bladed and three-bladed runners. The results show that the runner rotational frequency (fn is the dominant frequency of the pressure pulsations in the blades for ebb and flood turbine modes, and the gravitational effect, rather than rotor-stator interaction (RSI, plays an important role in a low head horizontal axial turbine. The amplitudes of the pressure pulsations on the blade side facing the guide vanes varies little with the water head. However, the amplitudes of the pressure pulsations on the blade side facing the diffusion tube linearly increase with the water head. These results could provide

  8. Fandom dan Konsumsi Media: Studi Etnografi Kelompok Penggemar Super Junior, ELF Jogja

    OpenAIRE

    Sari, Ratna Permata

    2016-01-01

    Korean Wave (music, movie, and drama), recently, accept a lot of attention from Indonesian teenagers. Thanks to the power of mass media, Korean music, or we called it KPop, beginning to spread it virus throughout the world by the emerging of Fandom. Super Junior as one of the pioneer of Korean boy band become the group that has the largest fan club in the world named ELF. This research examines the private media consumption behavior by ELF Jogja and the interaction between its members in orga...

  9. Physics with a 15-30 GeV electron accelerator (ELFE)

    International Nuclear Information System (INIS)

    Frois, B.; Pire, B.

    1993-01-01

    Proposals for ELFE (Electron Laboratory For Europe), a 15-30 GeV high luminosity, continuous beam electron accelerator are discussed. These proposals form an extensive research program on exclusive reactions to probe the evolution of correlated quarks systems. Using the nucleus itself as a microscopic detector is one of the important ideas of this program. The same reaction is measured using nuclei of different sizes and thus the differences are observed in the evolution from quarks and gluons to hadrons in the nuclear medium. A brief overview of the physics with ELFE is presented. (R.P.) 1 tab

  10. Models for electromagnetic scattering from the sea at extremely low grazing angles

    Science.gov (United States)

    Wetzel, Lewis B.

    1987-12-01

    The present state of understanding in the field of low-grazing-angle sea scatter is reviewed and extended. The important concept of shadowing is approached from the point of view of diffraction theory, and limits in wind speed and radar frequency are found for the application of shadowing theories based on geometrical optics. The implications of shadowing function based on illumination thresholding are shown to compare favorably with a variety of experimental results. Scattering from the exposed surface peaks is treated by a composite-surface Bragg model, and by wedge models using both physical optics and the method of equivalent currents. Curiously, the scattering levels predicted by these widely different approximations are all in fairly good agreement with experimental values for moderately low grazing angles (about 5 deg), with the physical optics wedge model being superior at 1 deg. A new scattering feature, the slosh, is introduced, with scattering behavior that resembles the temporal and polarization dependence of observed low angle returns from calm water. The plume model of scattering from breaking waves (from earlier work) is discussed as a source of high-intensity Sea Spikes. It is emphasized that the prediction of low angle scattering from the sea will require considerably more information about the shape, size, and distribution of the actual scattering features.

  11. Trajectories of psychopathology in extremely low birth weight survivors from early adolescence to adulthood: a 20-year longitudinal study.

    Science.gov (United States)

    Van Lieshout, Ryan J; Ferro, Mark A; Schmidt, Louis A; Boyle, Michael H; Saigal, Saroj; Morrison, Katherine M; Mathewson, Karen J

    2018-04-18

    Individuals born extremely preterm are exposed to significant perinatal stresses that are associated with an increased risk of psychopathology. However, a paucity of longitudinal studies has prevented the empirical examination of long-term, dynamic effects of perinatal adversity on mental health. Here, internalizing and externalizing problems from adolescence through adulthood were compared in individuals born at extremely low birth weight (ELBW; 2,500 g). Internalizing and externalizing data were collected over 20 years in three waves, during adolescence, young adulthood, and adulthood. Growth models were used to compare longitudinal trajectories in a geographically based sample of 151 ELBW survivors and 137 NBW control participants born between 1977 and 1982 matched for age, sex, and socioeconomic status at age 8. After adjusting for sex, socioeconomic and immigrant status, and family functioning, ELBW survivors failed to show the normative, age-related decline in internalizing problems over time relative to their NBW peers (β = .21; p Self-esteem (but not physical health, IQ, or maternal mood) partially mediated the association between ELBW status and internalizing problems. Extremely low birth weight survivors experienced a blunting of the expected improvement in depression and anxiety from adolescence to adulthood. These findings suggest that altered physiological regulatory systems supporting emotional and cognitive processing may contribute to the maintenance of internalizing problems in this population. © 2018 Association for Child and Adolescent Mental Health.

  12. Medium-Term Probabilistic Forecasting of Extremely Low Prices in Electricity Markets: Application to the Spanish Case

    Directory of Open Access Journals (Sweden)

    Antonio Bello

    2016-03-01

    Full Text Available One of the most relevant challenges that have arisen in electricity markets during the last few years is the emergence of extremely low prices. Trying to predict these events is crucial for market agents in a competitive environment. This paper proposes a novel methodology to simultaneously accomplish punctual and probabilistic hourly predictions about the appearance of extremely low electricity prices in a medium-term scope. The proposed approach for making real ex ante forecasts consists of a nested compounding of different forecasting techniques, which incorporate Monte Carlo simulation, combined with spatial interpolation techniques. The procedure is based on the statistical identification of the process key drivers. Logistic regression for rare events, decision trees, multilayer perceptrons and a hybrid approach, which combines a market equilibrium model with logistic regression, are used. Moreover, this paper assesses whether periodic models in which parameters switch according to the day of the week can be even more accurate. The proposed techniques are compared to a Markov regime switching model and several naive methods. The proposed methodology empirically demonstrates its effectiveness by achieving promising results on a real case study based on the Spanish electricity market. This approach can provide valuable information for market agents when they face decision making and risk-management processes. Our findings support the additional benefit of using a hybrid approach for deriving more accurate predictions.

  13. High current density ion beam obtained by a transition to a highly focused state in extremely low-energy region

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Y., E-mail: y.hirano@aist.go.jp, E-mail: hirano.yoichi@phys.cst.nihon-u.ac.jp [Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); College of Science and Technologies, Nihon University, Chiyodaku, Tokyo 101-0897 (Japan); Kiyama, S.; Koguchi, H. [Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Fujiwara, Y.; Sakakita, H. [Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Department of Engineering Mechanics and Energy, University of Tsukuba, Ibaraki 305-8577 (Japan)

    2015-11-15

    A high current density (≈3 mA/cm{sup 2}) hydrogen ion beam source operating in an extremely low-energy region (E{sub ib} ≈ 150–200 eV) has been realized by using a transition to a highly focused state, where the beam is extracted from the ion source chamber through three concave electrodes with nominal focal lengths of ≈350 mm. The transition occurs when the beam energy exceeds a threshold value between 145 and 170 eV. Low-level hysteresis is observed in the transition when E{sub ib} is being reduced. The radial profiles of the ion beam current density and the low temperature ion current density can be obtained separately using a Faraday cup with a grid in front. The measured profiles confirm that more than a half of the extracted beam ions reaches the target plate with a good focusing profile with a full width at half maximum of ≈3 cm. Estimation of the particle balances in beam ions, the slow ions, and the electrons indicates the possibility that the secondary electron emission from the target plate and electron impact ionization of hydrogen may play roles as particle sources in this extremely low-energy beam after the compensation of beam ion space charge.

  14. Simulating extreme low-discharge events for the Rhine using a stochastic model

    Science.gov (United States)

    Macian-Sorribes, Hector; Mens, Marjolein; Schasfoort, Femke; Diermanse, Ferdinand; Pulido-Velazquez, Manuel

    2017-04-01

    The specific features of hydrological droughts make them more difficult to be analysed than other water-related phenomena: longer time scales (months to several years) so less historical events are available, and the drought severity and associate damage depends on a combination of variables with no clear prevalence (e.g., total water deficit, maximum deficit and duration). As part of drought risk analysis, which aims to provide insight into the variability of hydrological conditions and associated socio-economic impacts, long synthetic time series should therefore be developed. In this contribution, we increase the length of the available inflow time series using stochastic autoregressive modelling. This enhancement could improve the characterization of the extreme range and can define extreme droughts with similar periods of return but different patterns that can lead to distinctly different damages. The methodology consists of: 1) fitting an autoregressive model (AR, ARMA…) to the available records; 2) generating extended time series (thousands of years); 3) performing a frequency analysis with different characteristic variables (total, deficit, maximum deficit and so on); and 4) selecting extreme drought events associated with different characteristic variables and return periods. The methodology was applied to the Rhine river discharge at location Lobith, where the Rhine enters The Netherlands. A monthly ARMA(1,1) autoregressive model with seasonally varying parameters was fitted and successfully validated to the historical records available since year 1901. The maximum monthly deficit with respect to a threshold value of 1800 m3/s and the average discharge for a given time span in m3/s were chosen as indicators to identify drought periods. A synthetic series of 10,000 years of discharges was generated using the validated ARMA model. Two time spans were considered in the analysis: the whole calendar year and the half-year period between April and September

  15. Novel spin transition between S = 5/2 and S = 3/2 in highly saddled iron(III) porphyrin complexes at extremely low temperatures.

    Science.gov (United States)

    Ohgo, Yoshiki; Chiba, Yuya; Hashizume, Daisuke; Uekusa, Hidehiro; Ozeki, Tomoji; Nakamura, Mikio

    2006-05-14

    A novel spin transition between S = 5/2 and S = 3/2 has been observed for the first time in five-coordinate, highly saddled iron(III) porphyrinates by EPR and SQUID measurements at extremely low temperatures.

  16. Innovative use of ICT in schools based on the findings in ELFE project

    NARCIS (Netherlands)

    Frederiksson, Ulf; Jedeskog, Gunilla; Plomp, T.

    2008-01-01

    The European e-Learning Forum for Education (ELFE) is a project initiated by the ETUCE (European Trade Union Committee on Education). An important objective of the project has been to study good experiences with implementing the use of ICT in schools. This objective has been broken down in seven

  17. ELF and VLF signatures of sprites registered onboard the low altitude satellite DEMETER

    Directory of Open Access Journals (Sweden)

    J. Błęcki

    2009-06-01

    Full Text Available We report the observation of ELF and VLF signature of sprites recorded on the low altitude satellite DEMETER during thunderstorm activity. At an altitude of ~700 km, waves observed on the E-field spectrograms at mid-to-low latitudes during night time are mainly dominated by up-going 0+ whistlers. During the night of 20 July 2007 two sprites have been observed around 20:10:08 UT from the observatory located on the top of the mountain Śnieżka in Poland (50°44'09" N, 15°44'21" E, 1603 m and, ELF and VLF data have been recorded by the satellite at about 1200 km from the region of thunderstorm activity. During this event, the DEMETER instruments were switched in the burst mode and it was possible to register the wave forms. It is shown that the two sprites have been triggered by two intense +CG lightning strokes (100 kA occurring during the same millisecond but not at the same location. Despite the distance DEMETER has recorded at the same time intense and unusual ELF and VLF emissions. It is shown that the whistler wave propagates from the thunderstorm regions in the Earth-ionosphere guide and enters in the ionosphere below the satellite. They last several tens of milliseconds and the intensity of the ELF waveform is close to 1 mV/m. A particularly intense proton whistler is also associated with these emissions.

  18. Fostering awareness of the pedagogical implications of World Englishes and ELF in teacher education in Italy

    Directory of Open Access Journals (Sweden)

    Paola Vettorel

    2016-09-01

    Full Text Available Teacher education represents an essential step to raise awareness of the sociolinguistic changes brought about by the current pluralization of English and by its lingua franca role. Within the pre-service teacher education programs run at the Department of Foreign Languages and Literatures, University of Verona, Italy, part of the English language course focused on issues related to World Englishes (WE and English as a lingua franca (ELF, aiming at fostering awareness of and active reflection upon their pedagogical implications. After taking into consideration recent developments in WE- and ELF-aware teacher education, we will report on findings from a research study involving trainee teachers attending the aforementioned courses for English in academic years 2012-13 to 2014-15. The main aim of the study has been to investigate whether, how and to what extent trainee teachers’ pedagogical knowledge and reasoning about a WE and ELF-informed perspective in teaching practices may undergo a change after attending these courses. Drawing upon different sets of data (questionnaires, reflections in e-learning discussion forums, interviews and final reports, the trainees’ increased awareness of and readiness to include a WE- and ELF-informed didactic approach after attending the course will be discussed, together with implications for foreign language teacher education.

  19. Angola. Petroleum discovery by Elf on the block number 17 in deep water

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    This article describes the petroleum discovery in deep water in Angola. The drilling was executed by 1365 meters deep and gave a petroleum of good quality. The Elf company emphasizes that it is its third discovery in deep water in the Guinea gulf after Nkossa and Moho in Congo. (N.C.)

  20. Mortality and Morbidity of Extremely Low Birth Weight Infants in the Mainland of China: A Multi-center Study

    Science.gov (United States)

    Lin, Hui-Jia; Du, Li-Zhong; Ma, Xiao-Lu; Shi, Li-Ping; Pan, Jia-Hua; Tong, Xiao-Mei; Li, Qiu-Ping; Zhou, Jian-Guo; Yi, Bing; Liu, Ling; Chen, Yun-Bing; Wei, Qiu-Fen; Wu, Hui-Qing; Li, Mei; Liu, Cui-Qing; Gao, Xi-Rong; Xia, Shi-Wen; Li, Wen-Bin; Yan, Chao-Ying; He, Ling; Liang, Kun; Zhou, Xiao-Yu; Han, Shu-Ping; Lyu, Qin; Qiu, Yin-Ping; Li, Wen; Chen, Dong-Mei; Lu, Hong-Ru; Liu, Xiao-Hong; Liu, Hong; Lin, Zhen-Lang; Liu, Li; Zhu, Jia-Jun; Xiong, Hong; Yue, Shao-Jie; Zhuang, Si-Qi

    2015-01-01

    Background: With the progress of perinatal medicine and neonatal technology, more and more extremely low birth weight (ELBW) survived all over the world. This study was designed to investigate the short-term outcomes of ELBW infants during their Neonatal Intensive Care Unit (NICU) stay in the mainland of China. Methods: All infants admitted to 26 NICUs with a birth weight (BW) patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity was 26.2%, 33.7%, 6.7%, 48.1%, and 41.4%, respectively. Ventilator associated pneumonia was the most common hospital acquired infection during hospitalization. Conclusions: Our study was the first survey that revealed the present status of ELBW infants in the mainland of China. The mortality and morbidity of ELBW infants remained high as compared to other developed countries. PMID:26481740

  1. Hospital outcomes of extremely low birth weight infants after introduction of donor milk to supplement mother's milk.

    Science.gov (United States)

    Verd, Sergio; Porta, Roser; Botet, Francesc; Gutiérrez, Antonio; Ginovart, Gemma; Barbero, Ana Herranz; Ciurana, Anna; Plata, Isabel Iglesias

    2015-04-01

    This study evaluated the impact of an exclusive human milk diet to nourish extremely low birth weight infants in the neonatal intensive care unit. This multicenter pre-post retrospective study included all inborn infants milk policy. The feeding protocol was unchanged in both periods. Collected data included maternal/infant demographics, infant clinical data, and enteral intake as mother's own milk, donor milk, and formula. Two hundred one infants were enrolled. Infant growth and other clinical outcomes were similar in both groups. Exposure to mother's own milk at discharge was not different. Median time in oxygen and duration of mechanical ventilation were significantly higher among formula-fed infants (63 versus 192 hours [p=0.046] and 24 versus 60 hours [p=0.016], respectively). Our results add evidence supporting the safety of donor milk. This study also found an association between exposure to formula in preterm infants and the requirement for respiratory support, a finding that warrants further investigation.

  2. Is there any role for terlipressin in the extremely low birth weight infant with refractory septic shock?

    Directory of Open Access Journals (Sweden)

    Francesca Bissolo

    2012-10-01

    Full Text Available Terlipressin, a synthetic long-acting analogue of vasopressin, has been investigated as a second line vasopressor in adults and children with refractory septic shock, i.e. not responding to fluid resuscitation and high-dose catecholamine administration. Little experience is available about the safety and efficacy of terlipressin in term and preterm newborns. We report the case of an extremely low birth weight infant with severe septic shock, unresponsive to fluids, noradrenalin and hydrocortisone, in whom terlipressin was attempted as a rescue drug. Despite three doses of terlipressin, administered 6-hourly, the patient remained profoundly hypotensive and eventually died. Further studies are required before any recommendation on the use of terlipressin in term or preterm newborns with septic shock can be made.

  3. Potential of essential fatty acid deficiency with extremely low fat diet in lipoprotein lipase deficiency during pregnancy: A case report

    Directory of Open Access Journals (Sweden)

    Anderson Gregory J

    2004-12-01

    Full Text Available Abstract Background Pregnancy in patients with lipoprotein lipase deficiency is associated with high risk of maternal pancreatitis and fetal death. A very low fat diet ( Case presentation A 23 year-old gravida 1 woman with primary lipoprotein lipase deficiency was seen at 7 weeks of gestation in the Lipid Clinic for management of severe hypertriglyceridemia that had worsened with pregnancy. While on her habitual fat intake of 10% of total calories, her pregnancy resulted in an exacerbation of the hypertriglyceridemia, which prompted further restriction of fat intake to Conclusions An extremely low fat diet in combination with topical sunflower oil and gemfibrozil administration was safely implemented in pregnancy associated with the severe hypertriglyceridemia of lipoprotein lipase deficiency.

  4. ELF5 in epithelial ovarian carcinoma tissues and biological behavior in ovarian carcinoma cells.

    Science.gov (United States)

    Yan, Hongchao; Qiu, Linglin; Xie, Xiaolei; Yang, He; Liu, Yongli; Lin, Xiaoman; Huang, Hongxiang

    2017-03-01

    The expression of E74-like factor 5 (ELF5) in epithelial ovarian carcinoma tissues and its effects on biological behavior in ovarian carcinoma cells were assessed in search for a new approach for gene treatment of epithelial ovarian carcinoma. RT-PCR technology was applied to detect the expression of ELF5 mRNA in epithelial ovarian carcinoma (n=49), borderline ovarian epithelial tumor (n=19), benign ovarian epithelial tumor (n=31) and normal ovarian tissues (n=40). Then, we transfected recombinant plasmid pcDNA3.1‑ELF5+EGFP into human ovarian carcinoma SKOV3 cells (recombinant plasmid group) in vitro and screened out stably transfected cells to conduct multiplication culture. Western blot analysis was performed to detect the expression of ELF5 protein in the different groups. Flow cytometry was employed to detect cell apoptosis and cycles. ELF5 mRNA in epithelial ovarian carcinoma and borderline ovarian epithelial tumor tissues were significantly lower (Pepithelial tumor and normal ovarian tissues. ELF5 protein expression in the cells of recombinant plasmid group was significantly higher compared with empty plasmid and blank control groups. The capacity of cell reproductive recombinant plasmid group at each time point decreased (P<0.05). Flow cytometry detection showed that 67.03% of cells in recombinant plasmid group was blocked in G0/G1 phase (P<0.05), compared with empty plasmid group (37.17%) and blank control group (38.24%). Apoptotic rate of recombinant plasmid group was significantly lower (31.4±1.9%; P<0.05), compared with that of empty plasmid group (9.1±2.2%) and blank control group (8.7±1.5%), and the differences were statistically significant. In conclusion, ELF5 interfered with cell cycle of human ovarian carcinoma SKOV3 cells and promoted apoptosis of human ovarian carcinoma SKOV3 cells inhibiting their growth and invasive capacity; and thus providing a new approach to gene treatment of ovarian carcinoma.

  5. High Flow Nasal Cannula Use Is Associated with Increased Morbidity and Length of Hospitalization in Extremely Low Birth Weight Infants.

    Science.gov (United States)

    Taha, Dalal K; Kornhauser, Michael; Greenspan, Jay S; Dysart, Kevin C; Aghai, Zubair H

    2016-06-01

    To determine differences in the incidence of bronchopulmonary dysplasia (BPD) or death in extremely low birth weight infants managed on high flow nasal cannula (HFNC) vs continuous positive airway pressure (CPAP). This is a retrospective data analysis from the Alere Neonatal Database for infants born between January 2008 and July 2013, weighing ≤1000 g at birth, and received HFNC or CPAP. Baseline demographics, clinical characteristics, and neonatal outcomes were compared between the infants who received CPAP and HFNC, or HFNC ± CPAP. Multivariable regression analysis was performed to control for the variables that differ in bivariate analysis. A total of 2487 infants met the inclusion criteria (941 CPAP group, 333 HFNC group, and 1546 HFNC ± CPAP group). The primary outcome of BPD or death was significantly higher in the HFNC group (56.8%) compared with the CPAP group (50.4%, P CPAP group compared with the CPAP group (OR 1.085, 95% CI 1.035-1.137, P = .001). The number of ventilator days, postnatal steroid use, days to room air, days to initiate or reach full oral feeds, and length of hospitalization were significantly higher in the HFNC and HFNC ± CPAP groups compared with the CPAP group. In this retrospective study, use of HFNC in extremely low birth weight infants is associated with a higher risk of death or BPD, increased respiratory morbidities, delayed oral feeding, and prolonged hospitalization. A large clinical trial is needed to evaluate long-term safety and efficacy of HFNC in preterm infants. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. High Flow Nasal Cannula Use Is Associated with Increased Morbidity and Length of Hospitalization in Extremely Low Birth Weight Infants

    Science.gov (United States)

    Taha, Dalal K.; Kornhauser, Michael; Greenspan, Jay S.; Dysart, Kevin C.; Aghai, Zubair H.

    2017-01-01

    Objective To determine differences in the incidence of bronchopulmonary dysplasia (BPD) or death in extremely low birth weight infants managed on high flow nasal cannula (HFNC) vs continuous positive airway pressure (CPAP). Study design This is aretrospective data analysis from the Alere Neonatal Database for infants born between January 2008 and July 2013, weighing ≤ 1000 g at birth, and received HFNC or CPAP. Baseline demographics, clinical characteristics, and neonatal outcomes were compared between the infants who received CPAP and HFNC, or HFNC ± CPAP. Multivariable regression analysis was performed to control for the variables that differ in bivariate analysis. Results A total of 2487 infants met the inclusion criteria (941 CPAP group, 333 HFNC group, and 1546 HFNC ± CPAP group). The primary outcome of BPD or death was significantly higher in the HFNC group (56.8%) compared with the CPAP group (50.4%, P < .05). Similarly, adjusted odds of developing BPD or death was greater in the HFNC ± CPAP group compared with the CPAP group (OR 1.085, 95% CI 1.035–1.137, P = .001). The number of ventilator days, postnatal steroid use, days to room air, days to initiate or reach full oral feeds, and length of hospitalization were significantly higher in the HFNC and HFNC ± CPAP groups compared with the CPAP group. Conclusions In this retrospective study, use of HFNC in extremely low birth weight infants is associated with a higher risk of death or BPD, increased respiratory morbidities, delayed oral feeding, and prolonged hospitalization. A large clinical trial is needed to evaluate long-term safety and efficacy of HFNC in preterm infants. PMID:27004673

  7. Maternal Black Race and Persistent Wheezing Illness in Former Extremely Low Gestational Age Newborns: Secondary Analysis of a Randomized Trial.

    Science.gov (United States)

    Wai, Katherine C; Hibbs, Anna M; Steurer, Martina A; Black, Dennis M; Asselin, Jeanette M; Eichenwald, Eric C; Ballard, Philip L; Ballard, Roberta A; Keller, Roberta L

    2018-04-04

    To evaluate the relationship between maternal self-reported race/ethnicity and persistent wheezing illness in former high-risk, extremely low gestational age newborns, and to quantify the contribution of socioeconomic, environmental, and biological factors on this relationship. We assessed persistent wheezing illness determined at 18-24 months corrected (for prematurity) age in survivors of a randomized trial. Parents/caregivers were surveyed for wheeze and inhaled asthma medication use quarterly to 12 months, and at 18 and 24 months. We used multivariable analysis to evaluate the relationship of maternal race to persistent wheezing illness, and identified mediators for this relationship via formal mediation analysis. Of 420 infants (25.2 ± 1.2 weeks of gestation and 714 ± 166 g at birth, 57% male, 34% maternal black race), 189 (45%) had persistent wheezing illness. After adjustment for gestational age, birth weight, and sex, infants of black mothers had increased odds of persistent wheeze compared with infants of nonblack mothers (OR = 2.9, 95% CI 1.9, 4.5). Only bronchopulmonary dysplasia, breast milk diet, and public insurance status were identified as mediators. In this model, the direct effect of race accounted for 69% of the relationship between maternal race and persistent wheeze, whereas breast milk diet, public insurance status, and bronchopulmonary dysplasia accounted for 8%, 12%, and 10%, respectively. Among former high-risk extremely low gestational age newborns, infants of black mothers have increased odds of developing persistent wheeze. A substantial proportion of this effect is directly accounted for by race, which may reflect unmeasured environmental influences, and acquired and innate biological differences. ClinicalTrials.gov: NCT01022580. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Demodulation effect is observed in neurones by exposure to low frequency modulated microwaves

    International Nuclear Information System (INIS)

    Perez-Bruzon, R N; Figols, T; Azanza, M J; Moral, A del

    2010-01-01

    Neurones exposure to a microwave (carrier f c =13.6 GHz; power P ≅ 5 mW; H o ≅ 0.10 Am -1 = 1.25 mOe; E 0 ≅ 3.5 V/m; ΔT ≅ 0.01 0 C; SAR: 3.1x10 -3 - 5.8x10 -3 W/Kg) EMF amplitude modulated by ELF-AC field (frequency, f m = 0-100 Hz) shows no electrophysiological effect under the carrier MF alone, but f requency resonances: at 2, 4, 8, 12, 16, 50, 100 Hz: demodulation effect. Resonances appear when applied ELF-MF is close to a dominant characteristic frequency of the neurone impulse Fourier spectrum. This is an interesting result considering that ELF-MF modulating RF or MW in the range of human EEG could induce frequency-resonant effects on exposed human brain.

  9. Measurement of electromagnetic waves in ELF and VLF bands to monitor lightning activity in the Maritime Continent

    Science.gov (United States)

    Yamashita, Kozo; Takahashi, Yukihiro; Ohya, Hiroyo; Tsuchiya, Fuminori; Sato, Mitsuteru; Matsumoto, Jun

    2013-04-01

    Data of lightning discharge has been focused on as an effective way for monitoring and nowcasting of thunderstorm activity which causes extreme weather. Spatial distribution of lightning discharge has been used as a proxy of the presence or absence of deep convection. Latest observation shows that there is extremely huge lightning whose scale is more than hundreds times bigger than that of averaged event. This result indicates that lightning observation should be carried out to estimate not only existence but also scale for quantitative evaluation of atmospheric convection. In this study, lightning observation network in the Maritime Continent is introduced. This network is consisted of the sensors which make possible to measure electromagnetic wave radiated from lightning discharges. Observation frequency is 0.1 - 40 kHz for the measurement of magnetic field and 1 - 40 kHz for that of electric field. Sampling frequency is 100 kHz. Waveform of electromagnetic wave is recorded by personal computer. We have already constructed observation stations at Tainan in Taiwan (23.1N, 121.1E), Saraburi in Thailand (14.5N, 101.0E), and Pontianak in Indonesia (0.0N, 109.4E). Furthermore, we plan to install the monitoring system at Los Banos in Philippines (14.18, 121.25E) and Hanoi in Viet Nam. Data obtained by multipoint observation is synchronized by GPS receiver installed at each station. By using data obtained by this network, location and scale of lightning discharge can be estimated. Location of lightning is determined based on time of arrival method. Accuracy of geolocation could be less than 10km. Furthermore, charge moment is evaluated as a scale of each lightning discharge. It is calculated from electromagnetic waveform in ELF range (3-30 kHz). At the presentation, we will show the initial result about geolocation for source of electromagnetic wave and derivation of charge moment value based on the measurement of ELF and VLF sferics.

  10. Azithromycin in the extremely low birth weight infant for the prevention of Bronchopulmonary Dysplasia: a pilot study

    Directory of Open Access Journals (Sweden)

    Anstead Michael I

    2007-06-01

    Full Text Available Abstract Background Azithromycin reduces the severity of illness in patients with inflammatory lung disease such as cystic fibrosis and diffuse panbronchiolitis. Bronchopulmonary dysplasia (BPD is a pulmonary disorder which causes significant morbidity and mortality in premature infants. BPD is pathologically characterized by inflammation, fibrosis and impaired alveolar development. The purpose of this study was to obtain pilot data on the effectiveness and safety of prophylactic azithromycin in reducing the incidence and severity of BPD in an extremely low birth weight (≤ 1000 grams population. Methods Infants ≤ 1000 g birth weight admitted to the University of Kentucky Neonatal Intensive Care Unit (level III, regional referral center from 9/1/02-6/30/03 were eligible for this pilot study. The pilot study was double-blinded, randomized, and placebo-controlled. Infants were randomized to treatment or placebo within 12 hours of beginning mechanical ventilation (IMV and within 72 hours of birth. The treatment group received azithromycin 10 mg/kg/day for 7 days followed by 5 mg/kg/day for the duration of the study. Azithromycin or placebo was continued until the infant no longer required IMV or supplemental oxygen, to a maximum of 6 weeks. Primary endpoints were incidence of BPD as defined by oxygen requirement at 36 weeks gestation, post-natal steroid use, days of IMV, and mortality. Data was analyzed by intention to treat using Chi-square and ANOVA. Results A total of 43 extremely premature infants were enrolled in this pilot study. Mean gestational age and birth weight were similar between groups. Mortality, incidence of BPD, days of IMV, and other morbidities were not significantly different between groups. Post-natal steroid use was significantly less in the treatment group [31% (6/19] vs. placebo group [62% (10/16] (p = 0.05. Duration of mechanical ventilation was significantly less in treatment survivors, with a median of 13 days (1–47

  11. How TotalFinaElf will reinforce its downstream leadership; Comment TotalFinaElf entend renforcer son leadership en aval

    Energy Technology Data Exchange (ETDEWEB)

    Legros, E.

    2002-06-01

    Invited by the 'para-petroleum industry club' of the French group of para-petroleum and para-gas companies (GEP) on April 2, 2002, J.P. Vettier, general director of the refining-marketing activity of TotalFinaElf company, described the new configuration of the downstream strategy of the French group, now the fourth biggest oil company in the world. This downstream activity seems to have profited from the different fusions that have led to the present day structure. (J.S.)

  12. Dunkerque`s refinery. Mobil-BP-Elf: matrimonial triangle with background anxiety; Raffinerie de Dunkerque. Mobil-BP-Elf: menage a trois sur fond d`inquietude

    Energy Technology Data Exchange (ETDEWEB)

    Vogue, A. de

    1997-08-01

    The annual production of the Dunkerque`s refinery (France) represents 330000 t of lubricants, 16000 t of paraffins, 17000 t of wax, 34000 t of extracts, 304000 t of diesel fuel and 300000 t of bitumens. From the legal aspect, Mobil is operator of the unit which belongs to an independent company held by BP (60%) and Elf (40%). After the BP-Mobil agreement was signed, the Dunkerque`s refinery entered into new Mobil`s network of 6 lubricants refineries which represent an overall over-capacity of 400000 t/year. This over-capacity is a consequence of export limitations due to profits reduction. (J.S.)

  13. Utility of the ELF Test for Detecting Steatohepatitis in Morbid Obese Patients with Suspicion of Nonalcoholic Fatty Liver Disease.

    Science.gov (United States)

    López, Iria Cebreiros; Aroca, Florentina Guzmán; Bernal, Maria Dolores Frutos; Mompeán, Juan Antonio Luján; Bernal, Águeda Bas; Martínez, Antonio Miguel Hernández; Barba, Enrique Martínez; Velasco, Jose Antonio Noguera; Paricio, Pascual Parilla

    2017-09-01

    Morbid obese patients have a high rate of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). NASH is related to the progression and poor evolution of chronic hepatopathy in NAFLD, so that its detection makes it possible to identify the subjects who are most at risk in order to prioritize treatment. The ELF test (Enhanced Liver Fibrosis test; Siemens Diagnostics, NY, USA) has been assessed for its capacity to detect fibrosis in patients with NAFLD, but its capacity for diagnosing NASH has not been checked. Our objective is to determine the utility of the ELF test for detecting NASH in morbid obese patients with suspected NAFLD. ELF values were determined in a cohort of obese patients who underwent bariatric surgery with suspected NAFLD. Liver biopsy was used as the reference standard. The values of ELF were significantly higher in patients with NASH (p = 0.002) and in those who presented with metabolic syndrome (p = 0.047). An ELF cut-off point of 8.72 allows the detection of patients with NASH with a sensitivity of 71.4% and a specificity of 74.1% (AUC = 0.742, p = 0.002). The ELF test is efficient for the identification of obese patients with NAFLD and early signs of steatohepatitis and fibrosis.

  14. Early corticosteroid treatment does not affect severity of unconjugated hyperbilirubinemia in extreme low birth weight preterm infants.

    Science.gov (United States)

    Hulzebos, Christian V; Bos, Arend F; Anttila, Eija; Hallman, Mikko; Verkade, Henkjan J

    2011-02-01

    To determine the relationship between early postnatal dexamethasone (DXM) treatment and the severity of hyperbilirubinemia in extreme low birth weight (ELBW) preterm infants. In 54 ELBW preterm infants, total serum bilirubin concentrations (TSB) and phototherapy (PT) data during the first 10 days were evaluated retrospectively. ELBW infants had participated in a randomized controlled trial of early DXM treatment which aimed to assess effects on chronic lung disease. Infants had been treated with DXM (0.25 mg/kg twice daily at postnatal day 1 and 2) or with placebo (normal saline). Analysis was performed on an intention to treat basis. Twenty-five Infants had been randomized into the DXM group; 29 into the placebo group. Mean (±SD) TSB [120 (±19) μmol/L vs. 123 (±28) μmol/L, DXM versus placebo, respectively] and maximum TSB [178 (±23) μmol/L vs. 176 (±48), DXM versus placebo, respectively] concentrations were similar. TSB concentrations peaked 30 h earlier in the DXM group (p ≤ 0.05). The need for PT as well as the duration of PT was similar in both groups. Early DXM treatment does not affect the severity of neonatal hyperbilirubinemia in ELBW preterm infants. Our results seem compatible with the concept that factors other than bilirubin conjugation capacity are important for the pathophysiology of neonatal jaundice in ELBW preterm infants. © 2010 The Author(s)/Acta Paediatrica © 2010 Foundation Acta Paediatrica.

  15. U.S. Nuclear Regulatory Commission Extremely Low Probability of Rupture pilot study: xLPR framework model user's guide

    International Nuclear Information System (INIS)

    Kalinich, Donald A.; Sallaberry, Cedric M.; Mattie, Patrick D.

    2010-01-01

    For the U.S. Nuclear Regulatory Commission (NRC) Extremely Low Probability of Rupture (xLPR) pilot study, Sandia National Laboratories (SNL) was tasked to develop and evaluate a probabilistic framework using a commercial software package for Version 1.0 of the xLPR Code. Version 1.0 of the xLPR code is focused assessing the probability of rupture due to primary water stress corrosion cracking in dissimilar metal welds in pressurizer surge nozzles. Future versions of this framework will expand the capabilities to other cracking mechanisms, and other piping systems for both pressurized water reactors and boiling water reactors. The goal of the pilot study project is to plan the xLPR framework transition from Version 1.0 to Version 2.0; hence the initial Version 1.0 framework and code development will be used to define the requirements for Version 2.0. The software documented in this report has been developed and tested solely for this purpose. This framework and demonstration problem will be used to evaluate the commercial software's capabilities and applicability for use in creating the final version of the xLPR framework. This report details the design, system requirements, and the steps necessary to use the commercial-code based xLPR framework developed by SNL.

  16. [Effect of extensively hydrolyzed formula on growth and development of infants with very/extremely low birth weight].

    Science.gov (United States)

    Gu, Chun-Yan; Jiang, Hui-Fen; Wang, Jin-Xiu

    2017-08-01

    To study the effect of extensively hydrolyzed formula on the growth and development in very low birth weight (VLBW) and extremely low birth weight (ELBW) infants. A total of 375 VLBW or ELBW infants were enrolled and divided into an observation group (187 infants) and a control group (188 infants) using a random number table. The infants in the observation group were given extensively hydrolyzed formula, and when the amount of extensively hydrolyzed formula reached 10 mL/time, it was changed to the standard formula for preterm infants. The infants in the control group were given standard formula for preterm infants. Both groups were fed for 4 consecutive weeks and were compared in terms of incidence rate of feeding intolerance, time to establish full enteral feeding, time to complete meconium excretion, number of spontaneous bowel movements, growth and development, motilin level at 4 and 10 days after feeding, and incidence rate of infection. Compared with the control group, the observation group had a lower rate of feeding intolerance (Pdevelopment, and reduce the incidence of infection in VLBW and ELBW infants.

  17. A Model of the Pulsating Extremely Low-mass White Dwarf Precursor WASP 0247–25B

    Energy Technology Data Exchange (ETDEWEB)

    Istrate, A. G. [Center for Gravitation, Cosmology, and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, WI 53201 (United States); Fontaine, G. [Département de Physique, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal, QC H3C 3J7 (Canada); Heuser, C., E-mail: istrate@uwm.edu [Dr. Karl Remeis-Observatory and ECAP, Astronomical Institute, Friedrich-Alexander University Erlangen-Nürnberg, Sternwartstr. 7, D-96049 Bamberg (Germany)

    2017-10-01

    We present an analysis of the evolutionary and pulsation properties of the extremely low-mass white dwarf precursor (B) component of the double-lined eclipsing system WASP 0247−25. Given that the fundamental parameters of that star have been obtained previously at a unique level of precision, WASP 0247−25B represents the ideal case for testing evolutionary models of this newly found category of pulsators. Taking into account the known constraints on the mass, orbital period, effective temperature, surface gravity, and atmospheric composition, we present a model that is compatible with these constraints and show pulsation modes that have periods very close to the observed values. Importantly, these modes are predicted to be excited. Although the overall consistency remains perfectible, the observable properties of WASP 0247−25B are closely reproduced. A key ingredient of our binary evolutionary models is represented by rotational mixing as the main competitor against gravitational settling. Depending on assumptions made about the values of the degree index ℓ for the observed pulsation modes, we found three possible seismic solutions. We discuss two tests, rotational splitting and multicolor photometry, that should readily identify the modes and discriminate between these solutions. However, this will require improved temporal resolution and higher S/N observations, which are currently unavailable.

  18. Extremely low genetic diversity across mangrove taxa reflects past sea level changes and hints at poor future responses.

    Science.gov (United States)

    Guo, Zixiao; Li, Xinnian; He, Ziwen; Yang, Yuchen; Wang, Wenqing; Zhong, Cairong; Greenberg, Anthony J; Wu, Chung-I; Duke, Norman C; Shi, Suhua

    2018-04-01

    The projected increases in sea levels are expected to affect coastal ecosystems. Tropical communities, anchored by mangrove trees and having experienced frequent past sea level changes, appear to be vibrant at present. However, any optimism about the resilience of these ecosystems is premature because the impact of past climate events may not be reflected in the current abundance. To assess the impact of historical sea level changes, we conducted an extensive genetic diversity survey on the Indo-Malayan coast, a hotspot with a large global mangrove distribution. A survey of 26 populations in six species reveals extremely low genome-wide nucleotide diversity and hence very small effective population sizes (N e ) in all populations. Whole-genome sequencing of three mangrove species further shows the decline in N e to be strongly associated with the speed of past changes in sea level. We also used a recent series of flooding events in Yalong Bay, southern China, to test the robustness of mangroves to sea level changes in relation to their genetic diversity. The events resulted in the death of half of the mangrove trees in this area. Significantly, less genetically diverse mangrove species suffered much greater destruction. The dieback was accompanied by a drastic reduction in local invertebrate biodiversity. We thus predict that tropical coastal communities will be seriously endangered as the global sea level rises. Well-planned coastal development near mangrove forests will be essential to avert this crisis. © 2017 John Wiley & Sons Ltd.

  19. A Model of the Pulsating Extremely Low-mass White Dwarf Precursor WASP 0247-25B

    Science.gov (United States)

    Istrate, A. G.; Fontaine, G.; Heuser, C.

    2017-10-01

    We present an analysis of the evolutionary and pulsation properties of the extremely low-mass white dwarf precursor (B) component of the double-lined eclipsing system WASP 0247-25. Given that the fundamental parameters of that star have been obtained previously at a unique level of precision, WASP 0247-25B represents the ideal case for testing evolutionary models of this newly found category of pulsators. Taking into account the known constraints on the mass, orbital period, effective temperature, surface gravity, and atmospheric composition, we present a model that is compatible with these constraints and show pulsation modes that have periods very close to the observed values. Importantly, these modes are predicted to be excited. Although the overall consistency remains perfectible, the observable properties of WASP 0247-25B are closely reproduced. A key ingredient of our binary evolutionary models is represented by rotational mixing as the main competitor against gravitational settling. Depending on assumptions made about the values of the degree index ℓ for the observed pulsation modes, we found three possible seismic solutions. We discuss two tests, rotational splitting and multicolor photometry, that should readily identify the modes and discriminate between these solutions. However, this will require improved temporal resolution and higher S/N observations, which are currently unavailable.

  20. Regional Brain Biometrics at Term-Equivalent Age and Developmental Outcome in Extremely Low-Birth-Weight Infants.

    Science.gov (United States)

    Melbourne, Launice; Murnick, Jonathan; Chang, Taeun; Glass, Penny; Massaro, An N

    2015-10-01

    This study aims to evaluate individual regional brain biometrics and their association with developmental outcome in extremely low-birth-weight (ELBW) infants. This is a retrospective study evaluating term-equivalent magnetic resonance imaging (TE-MRI) from 27 ELBW infants with known developmental outcomes beyond 12 months corrected age. Regional biometric measurements were performed by a pediatric neuroradiologist blinded to outcome data. Measures included biparietal width, transcerebellar diameter (TCD), deep gray matter area (DGMA), ventricular dilatation, corpus callosum, and interhemispheric distance. The relationship between regional biometrics and Bayley-II developmental scores were evaluated with linear regression models. The study cohort had an average±standard deviation birth weight of 684±150 g, gestational age of 24.6±2 weeks and 48% males. DGMA was significantly associated with both cognitive and motor outcomes. Significant associations were also observed between TCD and corpus callosum splenium with cognitive and motor outcomes, respectively. Other biometric measures were not associated with outcome (p>0.05). DGMAbiometrics reflecting impaired deep gray matter, callosal, and cerebellar size is associated with worse early childhood cognitive and motor outcomes. DGMA may be the most robust single biometric measure to predict adverse developmental outcome in preterm survivors. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  1. A Quality Improvement Initiative to Reduce the Need for Mechanical Ventilation in Extremely Low Gestational Age Neonates.

    Science.gov (United States)

    Templin, Ludivine; Grosse, Camille; Andres, Virginie; Robert, Clotilde Des; Fayol, Laurence; Simeoni, Umberto; Boubred, Farid

    2017-07-01

    Objective  Limiting early intubation and mechanical ventilation in extremely low gestational age neonates (ELGAN) may decrease neonatal morbidity and mortality. The aim of our study was to demonstrate the feasibility, efficacy, and tolerability of a delivery room respiratory management protocol, including delayed umbilical cord clamping (DUCC) in combination with optimized nCPAP with high PEEP levels and less invasive surfactant administration (LISA). Study Design  This cohort quality improvement study analyzed the respiratory and neonatal outcomes of all consecutive infants born between 24 +0 and 26 +6 weeks' gestation before (period 1, n  = 40) and after (period 2, n  = 52) implementing the new protocol. Results  Compared with the period 1 infants, the period 2 infants had a lower rate of intubation in the delivery room (31 vs. 90%, p  = 0.001) and were less likely to need mechanical ventilation on day 3 (28 vs. 62%, p  = 0.002) and during the hospital stay (75 vs. 92.5%, p  < 0.05). The two groups did not differ in terms of mortality or neonatal morbidity. Conclusion  A delivery room respiratory management protocol based on DUCC, optimized nCPAP with high PEEP levels, and LISA procedure is both feasible and safe, and improved ELGAN respiratory outcomes. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  2. ELF waves and ion resonances produced by an electron beam emitting rocket in the ionosphere

    International Nuclear Information System (INIS)

    Winckler, J.R.; Abe, Y.; Erickson, K.N.

    1986-01-01

    Results are reported from the ECHO-6 electron-beam-injection experiment, performed in the auroral-zone ionosphere on March 30, 1983 using a sounding rocket equipped with two electron guns and a free-flying plasma-diagnostics instrument package. The data are presented in extensive graphs and diagrams and characterized in detail. Large ELF wave variations, superposed on the strong beam-sector-directed quasi-dc component, are observed in the 100-eV beam-induced plasma when the beam is injected in a transverse spiral, but not when it is injected upward parallel to the magnetic-field line. ELF activity is found to be suppressed whenever the rocket passed through field lines with auroral activity, suggesting that the waves are produced by the interaction of the beam potentials, plasma currents, and return currents neutralizing the accelerator payload. 12 references

  3. Registration of ELF waves in rocket-satellite experiment with plasma injection

    Science.gov (United States)

    Korobeinikov, V. G.; Oraevskii, V. N.; Ruzhin, Iu. Ia.; Sobolev, Ia. P.; Skomarovskii, V. S.; Chmyrev, V. M.; Namazov, C. A.; Pokhunkov, A. A.; Nesmeianov, V. I.

    1992-12-01

    Two rocket KOMBI-SAMA experiments with plasma injection at height 100-240 km were performed in August 1987 in the region of Brazilian magnetic anomaly (L = 1.25). The launching time of the rocket was determined so that plasma injection was at the time when COSMOS 1809 satellite passed as close as possible to magnetic tube of injection. Caesium plasma jet was produced during not less than 300 s by an electric plasma generator separated from the payload. When the satellite passed the geomagnetic tube intersecting the injection region an enhancement of ELF emission at 140 Hz, 450 Hz by a factor of 2 was registered on board the satellite. An enhancement of energetic particle flux by a factor of 4-5 was registered on board the rocket. Observed ELF emission below 100 Hz is interpreted as the generation of oblique electromagnetic ion-cyclotron waves due to drift plasma instability at the front of the plasma jet.

  4. An entropy regularization method applied to the identification of wave distribution function for an ELF hiss event

    Science.gov (United States)

    Prot, Olivier; SantolíK, OndřEj; Trotignon, Jean-Gabriel; Deferaudy, Hervé

    2006-06-01

    An entropy regularization algorithm (ERA) has been developed to compute the wave-energy density from electromagnetic field measurements. It is based on the wave distribution function (WDF) concept. To assess its suitability and efficiency, the algorithm is applied to experimental data that has already been analyzed using other inversion techniques. The FREJA satellite data that is used consists of six spectral matrices corresponding to six time-frequency points of an ELF hiss-event spectrogram. The WDF analysis is performed on these six points and the results are compared with those obtained previously. A statistical stability analysis confirms the stability of the solutions. The WDF computation is fast and without any prespecified parameters. The regularization parameter has been chosen in accordance with the Morozov's discrepancy principle. The Generalized Cross Validation and L-curve criterions are then tentatively used to provide a fully data-driven method. However, these criterions fail to determine a suitable value of the regularization parameter. Although the entropy regularization leads to solutions that agree fairly well with those already published, some differences are observed, and these are discussed in detail. The main advantage of the ERA is to return the WDF that exhibits the largest entropy and to avoid the use of a priori models, which sometimes seem to be more accurate but without any justification.

  5. Phytoplankton extracellular phosphatases: investigation using the ELF (Enzyme Labelled Fluorescence) technique

    Czech Academy of Sciences Publication Activity Database

    Štrojsová, Alena; Vrba, Jaroslav

    2006-01-01

    Roč. 54, č. 4 (2006), s. 715-723 ISSN 1505-2249. [Symposium on European Freshwater Sciences /4./. Krakow, 22.08.2005-26.08.2005] R&D Projects: GA AV ČR(CZ) IAA6017202 Grant - others:FRVŠ(CZ) G4 1841 Institutional research plan: CEZ:AV0Z60170517 Keywords : algae * cyanobacteria * ELF97 phosphate * cell-specific activity Subject RIV: EH - Ecology, Behaviour Impact factor: 0.306, year: 2006

  6. Rapporteur Report: Sources and Exposure Metrics for ELF Epidemiology (Part 1) (invited paper)

    International Nuclear Information System (INIS)

    Matthes, R.

    1999-01-01

    High quality epidemiological studies on the possible link between exposure to non-ionizing radiation and human health effects are of great importance for radiation protection in this area. The main sources of ELF fields are domestic appliances, different electrical energy distribution systems and all kinds of electrical machinery and devices at the workplace. In general, ELF fields present in the environment, show complex temporal patterns and spatial distributions, depending on the generating source. The complete characterisation of the different field sources often requires highly sophisticated instrumentation, and this is therefore not feasible within the scope of epidemiological studies. On average, individual exposure from ELF fields is low in both the working environment and in residential areas. Only at certain workplaces are people subject to significant ELF exposure with regard to biological effects. Different methods have been developed to determine levels of exposure received by study subjects, with the aim to rank exposed and non-exposed groups in epidemiological studies. These include spot measurements, calculations or modelling. The different methods used to estimate total exposure in epidemiological studies may result to a differing extent in a misclassification of the study subjects. Equally important for future studies is the selection of the appropriate exposure metric. The most widely used metric so far is the time-weighted average and thus represents a quasi standard metric for use in epidemiological studies. Beside, wire codes have been used for a long time in residential studies and job titles are often used in occupational studies. On the basis of the experience gained in previous studies, it would be desirable to develop standardised, state-of-the-art protocols to improve exposure assessment. New surrogates and metrics were proposed as the basis for further studies. But only few of these have recently undergone preliminary testing. A

  7. ELF in English language teaching: Researching attitudes of Serbian academic community

    Directory of Open Access Journals (Sweden)

    Ošmjanski Vera B.

    2016-01-01

    Full Text Available The aim of the empirical part of the research was to explore the attitude of the Serbian academic community towards the English language used as lingua franca (ELF, i.e. neutral variety of the English language. The results might be a starting point in considering whether to include ELF in the language policy and, consequently, into English curricula in Serbia. The research included members of Serbian academic community, students of different departments, and English language teachers in the state owned and privately owned universities in Belgrade, Novi Sad and Nis. After examining their attitudes towards key postulates of ELF the conclusions are that it is necessary to start discussions about the concepts of the variety and to reassess current deeply rooted ideas about the English language from the perspective of modern linguistic trends. The need for a more liberal approach to the variety is not generated only in the needs of the market, i.e. those people to whom English is a practical means of international communication, but also the need to adjust ELT (English Language Teaching to modern linguistic tendencies and the European Council recommendations.

  8. DISCOVERY OF PULSATIONS, INCLUDING POSSIBLE PRESSURE MODES, IN TWO NEW EXTREMELY LOW MASS, He-CORE WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Hermes, J. J.; Montgomery, M. H.; Winget, D. E.; Bell, Keaton J.; Harrold, Samuel T. [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States); Brown, Warren R.; Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Gianninas, A.; Kilic, Mukremin, E-mail: jjhermes@astro.as.utexas.edu [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks Street, Norman, OK 73019 (United States)

    2013-03-10

    We report the discovery of the second and third pulsating extremely low mass (ELM) white dwarfs (WDs), SDSS J111215.82+111745.0 (hereafter J1112) and SDSS J151826.68+065813.2 (hereafter J1518). Both have masses < 0.25 M{sub Sun} and effective temperatures below 10, 000 K, establishing these putatively He-core WDs as a cooler class of pulsating hydrogen-atmosphere WDs (DAVs, or ZZ Ceti stars). The short-period pulsations evidenced in the light curve of J1112 may also represent the first observation of acoustic (p-mode) pulsations in any WD, which provide an exciting opportunity to probe this WD in a complimentary way compared to the long-period g-modes that are also present. J1112 is a T{sub eff} =9590 {+-} 140 K and log g =6.36 {+-} 0.06 WD. The star displays sinusoidal variability at five distinct periodicities between 1792 and 2855 s. In this star, we also see short-period variability, strongest at 134.3 s, well short of the expected g-modes for such a low-mass WD. The other new pulsating WD, J1518, is a T{sub eff} =9900 {+-} 140 K and log g =6.80 {+-} 0.05 WD. The light curve of J1518 is highly non-sinusoidal, with at least seven significant periods between 1335 and 3848 s. Consistent with the expectation that ELM WDs must be formed in binaries, these two new pulsating He-core WDs, in addition to the prototype SDSS J184037.78+642312.3, have close companions. However, the observed variability is inconsistent with tidally induced pulsations and is so far best explained by the same hydrogen partial-ionization driving mechanism at work in classic C/O-core ZZ Ceti stars.

  9. Special health care needs explains the effect of extremely low birth weight on math but not language achievement.

    Science.gov (United States)

    Litt, Jonathan S; Minich, Nori; Taylor, H Gerry; Hack, Maureen

    2017-12-01

    Extremely low birth weight (ELBW; math achievement compared to normal birth weight (NBW) peers. SHCN are associated with poor academic achievement among NBW children. We hypothesize that SHCN explain the effect of ELBW on math achievement. We compared age 14 Woodcock-Johnson Calculation standard scores between 181 ELBW infants and 115 NBW controls. Persistent SHCN included: 1) prescription medication or equipment use, 2) subspecialty or therapeutic service use, or 3) hospitalization. We used nonlinear marginal effects models to decompose the total effect of ELBW on math into the following 4 components: the effect of ELBW controlling for SHCN, the effect of SHCN controlling for ELBW, effect modification by SHCN, and mediated interaction where SHCN is both causal mediator and effect modifier. Models were adjusted for sociodemographic factors. ELBW adolescents had lower mean math scores than NBW peers (81.3 vs. 96.4). SHCN were more common among ELBW adolescents (54.1% vs. 27%). The total effect of ELBW on math scores was -15.7 points (95% CI -21.0, -10.5). The effect of birth weight alone was -7.6 points (95% CI -13.7, -1.4); the effect of SHCN alone was negligible. SHCN interaction and mediated interaction effects each accounted for 25% of the total effect. Birth weight alone explains only half of the effect of ELBW on math achievement. We found evidence of effect modification and mediation by SHCN. Understanding these explanatory pathways may lead to targeted interventions for improved outcomes. Copyright © 2017. Published by Elsevier B.V.

  10. Impact of Early Nutrition on Body Composition in Children Aged 9.5 Years Born with Extremely Low Birth Weight

    Directory of Open Access Journals (Sweden)

    Sonja Stutte

    2017-02-01

    Full Text Available To evaluate body composition, metabolism and growth as well as their interaction with early nutrition in former extremely low birth weight infants (ELBW, we assessed qualitative and quantitative nutritional intake during initial hospitalization and infantile growth parameters in 61 former ELBW infants with a birth weight <1000 g. In two follow-up exams, physical and biochemical development were measured at 5.7 and at 9.5 years. At the second follow-up, in addition to biochemical reassessment, body composition was analyzed by dual-energy x-ray absorptiometry (DEXA. Protein intake between birth and discharge was associated with weight gain in the first six months of life (r = 0.51; p < 0.01. Weight catch-up preceded height catch-up. Protein intake in early infancy correlated highly significantly with abdominal fat mass (r = 0.49; p < 0.05, but not with lean body mass at 9.5 years (r = 0.30; not significant (n.s.. In contrast to nutrient intake, birth weight was associated with lean body mass (r = 0.433; p < 0.001. Early protein and carbohydrate intake were associated with high-density lipoprotein (HDL-cholesterol, and early catch-up growth correlated with fasting insulin at follow-up. Stepwise linear regression demonstrated that protein intake predicted fat mass (p < 0.05, whereas only gender and birth weight standard deviation score (SDS contributed significantly to lean body mass variation (p < 0.05. Our results suggest an important impact of early nutrient intake on body composition and metabolism in later childhood in ELBW children.

  11. Factors affecting successful closure of hemodynamically significant patent ductus arteriosus with indomethacin in extremely low birth weight infants.

    Science.gov (United States)

    Yang, Chuan-Zhong; Lee, Jiun

    2008-05-01

    The incidence of patent ductus arteriosus (PDA) is high in extremely low birth weight (ELBW) infants. Indomethacin has been widely used in the prophylaxis and treatment of hemodynamically significant PDA. This retrospective study was undertaken to identify factors such as birth weight, gestational age, gender, fetal growth retardation, ductal size, timing of the first dose of indomethacin and side effects of indomethacin, which may affect the successful closure of the PDA with indomethacin in ELBW infants. A cohort of 139 ELBW infants who had received indomethacin treatment for PDA during a consecutive period of more than three years (September 2000 to December 2003) was retrospectively analyzed. Administration of indomethacin was associated with closure of PDA in 108 (77.7%) of 139 ELBW infants, and only 19.4% of infants required surgical ligation of the ductus eventually. There was no significant relationship between closure of PDA with gestational age, gender, fetal growth retardation, and ductal size. A higher birth weight and early use of indomethacin after birth could significantly increase the closure rate of PDA (P<0.05). Side effects of indomethacin such as transient oliguria and hyponatremia during indomethacin therapy did not affect PDA closure. Indomethacin is effective for the treatment of PDA in ELBW infants. A higher rate of ductal closure is related to the increase of birth weight. PDA closure with indomethacin is age-related, and early administration of indomethacin could increase PDA closure and reduce the incidence of hyponatremia. There is no significant difference in major morbidities such as bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), and retinopathy of prematurity (ROP) after early treatment. Early screening for hemodynamically significant PDA in ELBW infants and early treatment with indomethacin are recommended.

  12. Effect of short-term subaerial exposure on the cauliflower coral, Pocillopora damicornis, during a simulated extreme low-tide event

    KAUST Repository

    Castrilló n-Cifuentes, Ana Lucia; Lozano-Corté s, Diego; Zapata, Fernando A.

    2017-01-01

    There is increased interest in understanding how stress reduces coral resistance to disturbances and how acclimatization increases the ability of corals to resist future stress. Most extreme low tides at Gorgona Island, which expose reef flats to air, do not appear to negatively affect corals because corals usually do not undergo lethal bleaching during such events. However, coral physiology and fitness may be impacted by this phenomenon. The aim of this study was to evaluate whether corals exposed to air have modified biological functions to resist bleaching. To test this, an extreme low-tide event was simulated in the field. Colonies of Pocillopora damicornis were exposed to air for 15 or 40 min over the course of one, two, or three consecutive days. This procedure was repeated for one to three months. Colonies of P. damicornis exposed to air had reduced fecundity, decreased zooxanthellae density, and changed color from darker to lighter. However, the growth rate of exposed corals was similar to that of non-exposed colonies. We conclude that short periods of subaerial exposure during extreme low tides are not lethal to P. damicornis, but negatively affect sexual reproduction, which might have deleterious effects at the population level. The periodic occurrence of extreme low tides in the tropical eastern Pacific may be one factor responsible for the high rate of asexual reproduction (e.g., fragmentation) in pocilloporid corals of this region.

  13. Effect of short-term subaerial exposure on the cauliflower coral, Pocillopora damicornis, during a simulated extreme low-tide event

    KAUST Repository

    Castrillón-Cifuentes, Ana Lucia

    2017-02-06

    There is increased interest in understanding how stress reduces coral resistance to disturbances and how acclimatization increases the ability of corals to resist future stress. Most extreme low tides at Gorgona Island, which expose reef flats to air, do not appear to negatively affect corals because corals usually do not undergo lethal bleaching during such events. However, coral physiology and fitness may be impacted by this phenomenon. The aim of this study was to evaluate whether corals exposed to air have modified biological functions to resist bleaching. To test this, an extreme low-tide event was simulated in the field. Colonies of Pocillopora damicornis were exposed to air for 15 or 40 min over the course of one, two, or three consecutive days. This procedure was repeated for one to three months. Colonies of P. damicornis exposed to air had reduced fecundity, decreased zooxanthellae density, and changed color from darker to lighter. However, the growth rate of exposed corals was similar to that of non-exposed colonies. We conclude that short periods of subaerial exposure during extreme low tides are not lethal to P. damicornis, but negatively affect sexual reproduction, which might have deleterious effects at the population level. The periodic occurrence of extreme low tides in the tropical eastern Pacific may be one factor responsible for the high rate of asexual reproduction (e.g., fragmentation) in pocilloporid corals of this region.

  14. The value of Anti-Mullerian hormone in low and extremely low ovarian reserve in relation to live birth after in vitro fertilization

    NARCIS (Netherlands)

    Reijnders, I.F.; Nelen, W.L.D.M.; Hout, J. in't; Herwaarden, A.E. van; Braat, D.D.M.; Fleischer, K.

    2016-01-01

    OBJECTIVE: To determine the relation of Anti-Mullerian hormone (AMH) with live birth after in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) in women with (extremely) low ovarian reserve. STUDY DESIGN: This study was a retrospective cohort study in a Dutch tertiary fertility

  15. Effect of short-term subaerial exposure on the cauliflower coral, Pocillopora damicornis, during a simulated extreme low-tide event

    Science.gov (United States)

    Castrillón-Cifuentes, Ana Lucia; Lozano-Cortés, Diego F.; Zapata, Fernando A.

    2017-06-01

    There is increased interest in understanding how stress reduces coral resistance to disturbances and how acclimatization increases the ability of corals to resist future stress. Most extreme low tides at Gorgona Island, which expose reef flats to air, do not appear to negatively affect corals because corals usually do not undergo lethal bleaching during such events. However, coral physiology and fitness may be impacted by this phenomenon. The aim of this study was to evaluate whether corals exposed to air have modified biological functions to resist bleaching. To test this, an extreme low-tide event was simulated in the field. Colonies of Pocillopora damicornis were exposed to air for 15 or 40 min over the course of one, two, or three consecutive days. This procedure was repeated for one to three months. Colonies of P. damicornis exposed to air had reduced fecundity, decreased zooxanthellae density, and changed color from darker to lighter. However, the growth rate of exposed corals was similar to that of non-exposed colonies. We conclude that short periods of subaerial exposure during extreme low tides are not lethal to P. damicornis, but negatively affect sexual reproduction, which might have deleterious effects at the population level. The periodic occurrence of extreme low tides in the tropical eastern Pacific may be one factor responsible for the high rate of asexual reproduction (e.g., fragmentation) in pocilloporid corals of this region.

  16. Detection of endogenous alkaline phosphatase activity in intact cells by flow cytometry using the fluorogenic ELF-97 phosphatase substrate

    Science.gov (United States)

    Telford, W. G.; Cox, W. G.; Stiner, D.; Singer, V. L.; Doty, S. B.

    1999-01-01

    BACKGROUND: The alkaline phosphatase (AP) substrate 2-(5'-chloro-2'-phosphoryloxyphenyl)-6-chloro-4-(3H)-quinazolinone (ELF((R))-97 for enzyme-labeled fluorescence) has been found useful for the histochemical detection of endogenous AP activity and AP-tagged proteins and oligonucleotide probes. In this study, we evaluated its effectiveness at detecting endogenous AP activity by flow cytometry. METHODS: The ELF-97 phosphatase substrate was used to detect endogenous AP activity in UMR-106 rat osteosarcoma cells and primary cultures of chick chondrocytes. Cells were labeled with the ELF-97 reagent and analyzed by flow cytometry using an argon ultraviolet (UV) laser. For comparison purposes, cells were also assayed for AP using a Fast Red Violet LB azo dye assay previously described for use in detecting AP activity by flow cytometry. RESULTS: The ELF-97 phosphatase substrate effectively detected endogenous AP activity in UMR-106 cells, with over 95% of the resulting fluorescent signal resulting from AP-specific activity (as determined by levamisole inhibition of AP activity). In contrast, less than 70% of the fluorescent signal from the Fast Red Violet LB (FRV) assay was AP-dependent, reflecting the high intrinsic fluorescence of the unreacted components. The ELF-97 phosphatase assay was also able to detect very low AP activity in chick chondrocytes that was undetectable by the azo dye method. CONCLUSIONS: The ELF-97 phosphatase assay was able to detect endogenous AP activity in fixed mammalian and avian cells by flow cytometry with superior sensitivity to previously described assays. This work also shows the applicability of ELF-97 to flow cytometry, supplementing its previously demonstrated histochemical applications. Copyright 1999 Wiley-Liss, Inc.

  17. ELF Magnetic Fields, Transients and TWA Metrics (invited paper)

    Energy Technology Data Exchange (ETDEWEB)

    Kavet, R

    1999-07-01

    Residential measurements of ambient power frequency magnetic fields may serve as surrogates for personal exposures. There are few data available, however, to determine how far back in time this surrogacy holds. A limited amount of research on residential transients suggests that, all other factors being equivalent, larger transients may propagate within VHCC neighbourhoods than within LCC neighbourhoods. However, the presence of a conductive residential ground pathway also appears to be a potentially important factor associated with residential transient activity. The use of the TWA metric was prompted by the need for an exposure score simple enough to summarise an individual's exposure over a prior interval, yet specific to the agent of concern, namely the power frequency magnetic field. To the extent that the TWA exposure is associated with health outcomes in the absence of bias, including confounding, the TWA metric is important. (author)

  18. ELF Magnetic Fields, Transients and TWA Metrics (invited paper)

    International Nuclear Information System (INIS)

    Kavet, R.

    1999-01-01

    Residential measurements of ambient power frequency magnetic fields may serve as surrogates for personal exposures. There are few data available, however, to determine how far back in time this surrogacy holds. A limited amount of research on residential transients suggests that, all other factors being equivalent, larger transients may propagate within VHCC neighbourhoods than within LCC neighbourhoods. However, the presence of a conductive residential ground pathway also appears to be a potentially important factor associated with residential transient activity. The use of the TWA metric was prompted by the need for an exposure score simple enough to summarise an individual's exposure over a prior interval, yet specific to the agent of concern, namely the power frequency magnetic field. To the extent that the TWA exposure is associated with health outcomes in the absence of bias, including confounding, the TWA metric is important. (author)

  19. Measurements of intermediate-frequency electric and magnetic fields in households

    Energy Technology Data Exchange (ETDEWEB)

    Aerts, Sam, E-mail: sam.aerts@intec.ugent.be [Department of Information Technology, Ghent University/iMinds, iGent, Technologiepark-Zwijnaarde 15, B-9052 Ghent (Belgium); Calderon, Carolina [Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, Didcot, Oxon OX11 0RQ (United Kingdom); Valič, Blaž [Institute of Non-Ionizing Radiation (INIS), Pohorskega bataljona 215, Ljubljana 1000 (Slovenia); Maslanyj, Myron; Addison, Darren; Mee, Terry; Goiceanu, Cristian [Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, Didcot, Oxon OX11 0RQ (United Kingdom); Verloock, Leen; Van den Bossche, Matthias [Department of Information Technology, Ghent University/iMinds, iGent, Technologiepark-Zwijnaarde 15, B-9052 Ghent (Belgium); Gajšek, Peter [Institute of Non-Ionizing Radiation (INIS), Pohorskega bataljona 215, Ljubljana 1000 (Slovenia); Vermeulen, Roel [Institute for Risk Assessment Sciences, Department of Environmental Epidemiology, Utrecht University, Yalelaan 2, 3508 Utrecht (Netherlands); Röösli, Martin [Swiss Tropical and Public Health Institute (Swiss TPH), Socinstrasse 57, P.O. Box, 4002 Basel (Switzerland); University of Basel, Petersplatz 1, 4003 Basel (Switzerland); Cardis, Elisabeth [Barcelona Institute for Global Health (ISGlobal) and Municipal Institute of Medical Research (IMIM-Hospital del Mar), Doctor Aiguader, 88, 08003 Barcelona (Spain); Martens, Luc; Joseph, Wout [Department of Information Technology, Ghent University/iMinds, iGent, Technologiepark-Zwijnaarde 15, B-9052 Ghent (Belgium)

    2017-04-15

    Historically, assessment of human exposure to electric and magnetic fields has focused on the extremely-low-frequency (ELF) and radiofrequency (RF) ranges. However, research on the typically emitted fields in the intermediate-frequency (IF) range (300 Hz to 1 MHz) as well as potential effects of IF fields on the human body remains limited, although the range of household appliances with electrical components working in the IF range has grown significantly (e.g., induction cookers and compact fluorescent lighting). In this study, an extensive measurement survey was performed on the levels of electric and magnetic fields in the IF range typically present in residences as well as emitted by a wide range of household appliances under real-life circumstances. Using spot measurements, residential IF field levels were found to be generally low, while the use of certain appliances at close distance (20 cm) may result in a relatively high exposure. Overall, appliance emissions contained either harmonic signals, with fundamental frequencies between 6 kHz and 300 kHz, which were sometimes accompanied by regions in the IF spectrum of rather noisy, elevated field strengths, or much more capricious spectra, dominated by 50 Hz harmonics emanating far in the IF domain. The maximum peak field strengths recorded at 20 cm were 41.5 V/m and 2.7 A/m, both from induction cookers. Finally, none of the appliance emissions in the IF range exceeded the exposure summation rules recommended by the International Commission on Non-Ionizing Radiation Protection guidelines and the International Electrotechnical Commission (IEC 62233) standard at 20 cm and beyond (maximum exposure quotients EQ{sub E} 1.0 and {sub E}Q{sub H} 0.13). - Highlights: • Survey of residential electric and magnetic fields at intermediate frequencies (IF). • IF-EF and -MF emitted by 280 household appliances were characterised. • Strongest emitters were induction cookers, CFLs, LCD-TVs, and microwave ovens. • No

  20. Measurements of intermediate-frequency electric and magnetic fields in households

    International Nuclear Information System (INIS)

    Aerts, Sam; Calderon, Carolina; Valič, Blaž; Maslanyj, Myron; Addison, Darren; Mee, Terry; Goiceanu, Cristian; Verloock, Leen; Van den Bossche, Matthias; Gajšek, Peter; Vermeulen, Roel; Röösli, Martin; Cardis, Elisabeth; Martens, Luc; Joseph, Wout

    2017-01-01

    Historically, assessment of human exposure to electric and magnetic fields has focused on the extremely-low-frequency (ELF) and radiofrequency (RF) ranges. However, research on the typically emitted fields in the intermediate-frequency (IF) range (300 Hz to 1 MHz) as well as potential effects of IF fields on the human body remains limited, although the range of household appliances with electrical components working in the IF range has grown significantly (e.g., induction cookers and compact fluorescent lighting). In this study, an extensive measurement survey was performed on the levels of electric and magnetic fields in the IF range typically present in residences as well as emitted by a wide range of household appliances under real-life circumstances. Using spot measurements, residential IF field levels were found to be generally low, while the use of certain appliances at close distance (20 cm) may result in a relatively high exposure. Overall, appliance emissions contained either harmonic signals, with fundamental frequencies between 6 kHz and 300 kHz, which were sometimes accompanied by regions in the IF spectrum of rather noisy, elevated field strengths, or much more capricious spectra, dominated by 50 Hz harmonics emanating far in the IF domain. The maximum peak field strengths recorded at 20 cm were 41.5 V/m and 2.7 A/m, both from induction cookers. Finally, none of the appliance emissions in the IF range exceeded the exposure summation rules recommended by the International Commission on Non-Ionizing Radiation Protection guidelines and the International Electrotechnical Commission (IEC 62233) standard at 20 cm and beyond (maximum exposure quotients EQ E 1.0 and E Q H 0.13). - Highlights: • Survey of residential electric and magnetic fields at intermediate frequencies (IF). • IF-EF and -MF emitted by 280 household appliances were characterised. • Strongest emitters were induction cookers, CFLs, LCD-TVs, and microwave ovens. • No emissions exceeded

  1. RISK FACTORS FOR THE EARLY NEONATAL MORTALITY IN NEWBORNS WITH VERY LOW AND EXTREMELY LOW BIRTH WEIGHT

    Directory of Open Access Journals (Sweden)

    О. V. Lebedeva

    2014-01-01

    Full Text Available Objective: Our aim was to assess the association of perinatal factors with the early neonatal mortality in newborns with very low (VLBW and extremely low birth weight (ELBW.Methods: The statistical data was carried out, that is analysis of 17 perinatal factors of 28 newborns with an ELBW with gestation of 23–27 weeks and 18 newborns with a VLBW with gestation of 28–32 weeks, who died in the first 7 days of life. The comparison group consisted of 25 newborns with an ELBW and 56 children with a VLBW with gestation of 25–27 and 28–32 weeks, respectively, who survived the early neonatal period. The association of risk factors with the early neonatal mortality was assessed by means of a multiple-factor logistic regression analysis. A critical p error level was set equal to 0.05. Results: In newborns with a VLBW the increased risk of the early neonatal mortality depended on a gestation term (OR 4.40, 95% CI 1.56–11.71; р = 0.002 and emergency Caesarean section (OR 7.48, 95% CI 1.28–43.74; р = 0.008. A vaginal birth increased the survival chance (OR 0.12, 95% CI 0.01–0.86; р = 0.032. Newborns with an ELBW had the following factors of the increased risk of the early neonatal mortality: gestational age (OR 2.86, 95% CI 1.06–7.73; р = 0.038, Apgar score at the 5th minute (OR 1.91, 95% CI 0.99–3.69; р = 0.050 and presence of chorioamnionitis (OR 5.45, 95% CI 1.0–29.53; p = 0.048. An elective Caesarean section increased the survival chance (OR 0.02, 95% CI 0.001–0.44; p = 0.048. Conclusion: Summarizing the obtained data, we can conclude that besides a gestational age the risk of early neonatal mortality in newborns with a VLBW may be increased due to the emergency Caesarean section, with an ELBW — due to a low Apgar score at the 5th minute and the presence of mother's chorioamnionitis. A vaginal birth in newborns with a VLBW and an elective Caesarean section in children with an ELBW increase survival chances.

  2. An 8-month history of meningitis in an extremely low birth weight infant? - Long-lasting Infection with Ureaplasma parvum.

    Science.gov (United States)

    Glaser, K; Wohlleben, M; Speer, C P

    2015-02-01

    Ureaplasma spp. have been implicated in the pathogenesis of both preterm labor and neonatal morbidity including pneumonia and sepsis and the development of chronic lung disease of prematurity. Data on Ureaplasma meningitis are limited and partly controversially discussed. We report the unique case of a 9-month-old infant with progressive internal hydrocephalus of unknown origin and developmental delay due to a history of>200 days of inflammation of the central nervous system. The female extremely low birth weight infant had been referred to our hospital for ventriculoperitoneal shunt implantation. She had been born at 26+3 weeks of gestation with a birth weight of 940 g. With the exception of a moderate respiratory distress syndrome, postnatal period had been reported uneventful. However, internal hydrocephalus had become manifest at 4 weeks of postnatal age. Intraventricular hemorrhage had not been documented by cranial ultrasound and magnetic resonance imaging. Cerebrospinal fluid (CSF) analysis had repetitively revealed pronounced inflammation reflected by pleocytosis (50-86 leukocytes/μL, 60% lymphocytes), CSF protein levels of 578-1,026 mg/dL and undetectable CSF glucose. Although suggesting bacterial meningitis, microbial diagnostics had not been indicative, and empirical antibiotics had not affected the CSF findings. On admission to our hospital, CSF analysis still documented significant inflammation (125 leukocytes/μL, CSF protein 565 mg/dL, CSF glucoseUreaplasma spp. and Mycoplasma hominis. U. parvum was detected in CSF by culture and PCR, no other pathogens were isolated. On intravenous treatment with chloramphenicol, CSF profile continuously normalized, and cultures and PCR became negative. Treatment was continued for 3 weeks, and the infant was discharged after uncomplicated ventriculoperitoneal shunt placement. During a 12-month observation period she has shown encouraging recovery. In preterm infants, in particular, internal hydrocephalus of

  3. Comparison of Oral Ibuprofen and Intravenous Indomethacin for the Treatment of Patent Ductus Arteriosus in Extremely Low Birth Weight Infants

    Directory of Open Access Journals (Sweden)

    Eun Mi Yang

    2013-01-01

    Full Text Available Objective: There are few published reports concerning the efficacy of oral ibuprofen for the treatment of patent ductus arteriosus (PDA in extremely low birth weight (ELBW infants. Oral ibuprofen was compared to intravenous indomethacin regarding efficacy and safety in the treatment of PDA in infants weighting less than 1,000 g at birth. Method: This was a retrospective study in a single center. Data on ELBW infants who had an echocardiographically confirmed PDA were collected. The infants were treated with either intravenous indomethacin or oral ibuprofen. Rate of ductal closure, need for additional treatment, drug-related side effects or complications, and mortality were compared between the two treatment groups. Result: 26 infants who received indomethacin and 22 infants who received ibuprofen were studied. The overall rate of ductal closure was similar between the two treatments: it occurred in 23 of 26 infants (88.5% treated with indomethacin, and in 18 of 22 infants (81.8% treated with ibuprofen (p = 0.40. The rate of surgical ligation (11.5% versus 18.2%; p = 0.40 did not differ significantly between the two treatment groups. No significant difference was found in post-treatment serum creatinine concentrations between the two groups. There were no significant differences regarding additional side effects or complications. Conclusion: In ELBW infants, oral ibuprofen is as efficacious as intravenous indomethacin for the treatment of PDA. There were no differences between the two drugs with respect to safety. Oral ibuprofen could be used as an alternative agent for the treatment of PDA in ELBW infants. Resumo: Objetivo: Existem poucos relatórios publicados com relação à eficácia do ibuprofeno via oral no tratamento da persistência do canal arterial (PCA em neonatos com extremo baixo peso ao nascer (EBPN. Comparamos o ibuprofeno via oral à indometacina intrave- nosa no que diz respeito à eficácia e segurança no tratamento de

  4. TotalFina+Elf, how to fight against the evidence?; TotalFina+Elf, comment lutter contre l'evidence?

    Energy Technology Data Exchange (ETDEWEB)

    Marion, G. [Ecole Nationale Superieure des Mines, 69 - Lyon (France)

    2000-09-01

    TotaIFina's successful bid for taking over Elf represents the victory of a certain type of 'discourse'. The strategist's ability to market his views resembles the marketer's ability to promote a product through packaging and advertising. Analyzing the publicity war between these two firms during the summer of 1999 sheds light on the strategist's ability to 'make strategy with words'. Out of the variety of explanatory factors and arguments for the success of such a takeover bid. 'managerial discourse' is not to be overlooked as a means for 'enacting' a strategy. (author)

  5. Anomalous ELF phenomena in the Schumann resonance band as observed at Moshiri (Japan in possible association with an earthquake in Taiwan

    Directory of Open Access Journals (Sweden)

    M. Hayakawa

    2008-12-01

    Full Text Available The ELF observation at Moshiri (geographic coordinates: 44.29° N, 142.21° E in Hokkaido, Japan, was used to find anomalous phenomena in the Schumann resonance band, possibly associated with a large earthquake (magnitude of 7.8 in Taiwan on 26 December 2006. The Schumann resonance signal (fundamental (n=1, 8 Hz; 2nd harmonic, 14 Hz, 3rd harmonic, 20 Hz, 4th, 26 Hz etc. is known to be supported by electromagnetic radiation from the global thunderstorms, and the anomaly in this paper is characterized by an increase in intensity at frequencies from the third to fourth Schumann resonance modes mainly in the BEW component with a minor corresponding increase in the BNS component also. Spectral modification takes place only in the interval of 21:00 UT±1 h, which corresponds to the global lightning activity concentrated in America. While distortions were absent in other lightning-active UT intervals, in particular, around 08:00 UT±1 h (Asian thunderstorms and around 15±1 h (African lightning activity. The anomaly occurred on 23 December three days prior to the main shock. The results observed were explained in terms of ELF radio wave perturbation caused by the lower ionospheric depression around the earthquake epicenter. The difference in the path lengths between the direct radio wave from an active global thunderstorm center and the wave scattered from the non-uniformity above Taiwan causes interference at higher resonance modes, which is successful in explaining the observational data.

  6. Inactivation of TGF-β signaling in lung cancer results in increased CDK4 activity that can be rescued by ELF

    International Nuclear Information System (INIS)

    Baek, Hye Jung; Kim, Sang Soo; Silva, Fabio May da; Volpe, Eugene A.; Evans, Stephen; Mishra, Bibhuti; Mishra, Lopa; Blair Marshall, M.

    2006-01-01

    Escape from TGF-β inhibition of proliferation is a hallmark of multiple cancers including lung cancer. We explored the role of ELF, crucial TGF-β adaptor protein identified from endodermal progenitor cells, in lung carcinogenesis and cell-cycle regulation. Interestingly, elf -/- mice develop multiple defects that include lung, liver, and cardiac abnormalities. Four out of 6 lung cancer and mesothelioma cell lines displayed deficiency of ELF expression with increased CDK4 expression. Immunohistochemistry and Western blot analysis of primary human lung cancers also showed decreased ELF expression and overexpression of CDK4. Moreover, rescue of ELF in ELF-deficient cell lines decreased the expression of CDK4 and resulted in accumulation of G1/S checkpoint arrested cells. These results suggest that disruption in TGF-β signaling mediated by loss of ELF in lung cancer leads to cell-cycle deregulation by modulating CDK4 and ELF highlights a key role of TGF-β adaptor protein in suppressing early lung cancer

  7. ELF-test less accurately identifies liver cirrhosis diagnosed by liver stiffness measurement in non-Asian women with chronic hepatitis B

    NARCIS (Netherlands)

    Harkisoen, S.; Boland, G. J.; van den Hoek, J. A. R.; van Erpecum, K. J.; Hoepelman, A. I. M.; Arends, J. E.

    2014-01-01

    The enhanced liver fibrosis test (ELF-test) has been validated for several hepatic diseases. However, its performance in chronic hepatitis B virus (CHB) infected patients is uncertain. This study investigates the diagnostic value of the ELF test for cirrhosis identified by liver stiffness

  8. A Potential Role of Chronic Exposure to Extremely Low-Frequency Electromagnetic Fields in Triggering Persistent Pain Post Breast Cancer Surgery: A Review

    Directory of Open Access Journals (Sweden)

    Azadeh Stark

    2017-10-01

    Full Text Available Persistent Pain after Breast Cancer Surgery (PPBCS ranks second to amputation of extremities for neuropathic chronic pain. PPBCS is associated with the formation of intercostobrachial neuroma bulbs along the lateral chest. These neuroma bulbs are either un-/thinly myelinated and express hypersensitivity to environmental stimuli. Hypersensitivity is manifested as spontaneous pain in response to innocuous stimuli and exaggerating pain in response to noxious stimuli. Excision of neuromas, a common intervention to alleviate pain, has been reported as ineffective. Experience of individuals with amputation of extremities and experimental models of human nerve injuries confirm anthropogenic EMF evoke excruciating pain. Findings from invitro and animal studies clearly support that EMF exposure depolarizes cell membranes, interrupts voltage gated calcium channels which then activates peripheral sensory neurons and initiates propagation of a train of action potentials along the axons of primary afferent nerve fibers. The World Health Organization guidelines, established based on approximation of the human anatomy are limited and assumes no potential compounding effects of nerve injuries or alterations of physiological milieu of tissues. The objective of this review is to direct the attention of the medical community to the potential role of anthropogenic EMF as a risk factor for persistent pain after breast surgery. Patients rely heavily on the recommendations of their providers to manage their pain. The current epidemic of opioid abuse in the US has been partially attributed to the high prescription rate of opioid-based pain killers. Understanding the potential triggers of chronic pain can reduce dependency on pharmaceutical agents.

  9. Assessment of levels of occupational exposure to extremely low frequency electric and magnetic fields in data centres in Greater Accra Region-Ghana

    International Nuclear Information System (INIS)

    Kalognia, Joshua

    2016-07-01

    Data centres use a lot of power, consumed by two main usages: power required to run the actual equipment and power required to cool the equipment. Usage of electricity results in the production of electric and magnetic fields (EMF). Even though electricity is useful in human lives, there have been reported cases of adverse health effects from EMF generated from its use. Because the use of electricity is ubiquitous and plays a vital role in society’s economy, the possibility of harm from EMF to electric utility customers and workers deserves attention.The Electric and Magnetic fields for workers in data center in the Greater Accra Region have been assessed. The fundamental objective was to determine the levels of the electric and magnetic fields and to assess the extent of exposure of workers in the data centre to these fields. The results obtained for the electric field intensities in the data centre ranged from 6.03E-03 ± 7.54E-04 kVm"-"1 to 2.33E-04 ± 8.82E-05 kVm"-"1.The results obtained for the resultant field strength in the data centre ranged from 3.12E-01± 8.77E-03 μT to 6.57E-02 ± 7.38E-03 μT. The results obtained for the magnetic flux density ranged from 3.9E-07 ± 8.77E-03 μT to 7.27E-08 ± 7.31E-03 μT. The results obtained for the induced current density ranged from 2.37E-06 ± 1.50E-02 mA/m"2 to 2.46E-07 ± 9.99E-03 mA/m"2. Data obtained are below the basic restrictions for induced current density and reference levels for electric field and magnetic flux density set by the International. (au)

  10. Photoperiodism as a Modifier of Effect of Extremely Low-Frequency Electromagnetic Field on Morphological Properties of Pineal Gland

    Directory of Open Access Journals (Sweden)

    Tamara Lukač

    2006-08-01

    Full Text Available The aim of our study was to determine, using histological and stereological methods, whether photoperiodism has any impact on the effects that chronic (three-month long exposure to LF-EMF (50Hz has on morphological characteristics on rat's pineal gland. The experiment was performed on 48 Mill Hill male rats (24 experimental and 24 control. Upon birth, 24 rats were exposed for 7h a day, 5 days a week for 3 months to LF-EMF (50 Hz, 50-500microT, 10V/m. In the winter (short days, long nights, the activity of the pineal gland and neuroendocrine sensitivity is increased. The study was performed both during summer and winter, following the identical protocol. After sacrifice of animals, samples of pineal gland were processed for HE staining and then were analyzed using the methods of stereology. The most significant changes in epiphysis in the first group of animals in wintertime are: altered glandular feature, hyperemia, reduced pinealocytes with pale pink, poor cytoplasm and irregular, stick-form nuclei. In the second group (II pinealocytes are enlarged, with vacuolated cytoplasm and hyper chromatic, enlarged nucleus. Morphological changes of pineal gland at rats in the summertime were not as intense as in the winter and finding of the gland in the group II is compatible with those from the control group. Stereological results show both in winter and summer in the first group the decrease of volume density of pinealocytes, their cytoplasm and nuclei and in the second group in winter increase the volume density of pinealocytes, cytoplasm and nuclei, while in the second group the results in summertime are equal to those from the control group. Photoperiodism is modifier of effect of LF-EMF on morphological structure of pineal gland, because the gland recovery is incomplete in winter and reversible in summer.

  11. Extremely low frequency electromagnetic fields promote mesenchymal stem cell migration by increasing intracellular Ca2+ and activating the FAK/Rho GTPases signaling pathways in vitro.

    Science.gov (United States)

    Zhang, Yingchi; Yan, Jiyuan; Xu, Haoran; Yang, Yong; Li, Wenkai; Wu, Hua; Liu, Chaoxu

    2018-05-21

    The ability of mesenchymal stem cells (MSCs) to migrate to the desired tissues or lesions is crucial for stem cell-based regenerative medicine and tissue engineering. Optimal therapeutics for promoting MSC migration are expected to become an effective means for tissue regeneration. Electromagnetic fields (EMF), as a noninvasive therapy, can cause a lot of biological changes in MSCs. However, whether EMF can promote MSC migration has not yet been reported. We evaluated the effects of EMF on cell migration in human bone marrow-derived MSCs. With the use of Helmholtz coils and an EMF stimulator, 7.5, 15, 30, 50, and 70 Hz/1 mT EMF was generated. Additionally, we employed the L-type calcium channel blocker verapamil and the focal adhesion kinase (FAK) inhibitor PF-573228 to investigate the role of intracellular calcium content, cell adhesion proteins, and the Rho GTPase protein family (RhoA, Rac1, and Cdc42) in EMF-mediated MSC migration. Cell adhesion proteins (FAK, talin, and vinculin) were detected by Western blot analysis. The Rho GTPase protein family activities were assessed by G-LISA, and F-actin levels, which reflect actin cytoskeletal organization, were detected using immunofluorescence. All the 7.5, 15, 30, 50, and 70 Hz/1 mT EMF promoted MSC migration. EMF increased MSC migration in an intracellular calcium-dependent manner. Notably, EMF-enhanced migration was mediated by FAK activation, which was critical for the formation of focal contacts, as evidenced by increased talin and vinculin expression. Moreover, RhoA, Rac1, and Cdc42 were activated by FAK to increase cytoskeletal organization, thus promoting cell contraction. EMF promoted MSC migration by increasing intracellular calcium and activating the FAK/Rho GTPase signaling pathways. This study provides insights into the mechanisms of MSC migration and will enable the rational design of targeted therapies to improve MSC engraftment.

  12. Influence of extremely low frequency, low energy electromagnetic fields and combined mechanical stimulation on chondrocytes in 3-D constructs for cartilage tissue engineering.

    Science.gov (United States)

    Hilz, Florian M; Ahrens, Philipp; Grad, Sibylle; Stoddart, Martin J; Dahmani, Chiheb; Wilken, Frauke L; Sauerschnig, Martin; Niemeyer, Philipp; Zwingmann, Jörn; Burgkart, Rainer; von Eisenhart-Rothe, Rüdiger; Südkamp, Norbert P; Weyh, Thomas; Imhoff, Andreas B; Alini, Mauro; Salzmann, Gian M

    2014-02-01

    Articular cartilage, once damaged, has very low regenerative potential. Various experimental approaches have been conducted to enhance chondrogenesis and cartilage maturation. Among those, non-invasive electromagnetic fields have shown their beneficial influence for cartilage regeneration and are widely used for the treatment of non-unions, fractures, avascular necrosis and osteoarthritis. One very well accepted way to promote cartilage maturation is physical stimulation through bioreactors. The aim of this study was the investigation of combined mechanical and electromagnetic stress affecting cartilage cells in vitro. Primary articular chondrocytes from bovine fetlock joints were seeded into three-dimensional (3-D) polyurethane scaffolds and distributed into seven stimulated experimental groups. They either underwent mechanical or electromagnetic stimulation (sinusoidal electromagnetic field of 1 mT, 2 mT, or 3 mT; 60 Hz) or both within a joint-specific bioreactor and a coil system. The scaffold-cell constructs were analyzed for glycosaminoglycan (GAG) and DNA content, histology, and gene expression of collagen-1, collagen-2, aggrecan, cartilage oligomeric matrix protein (COMP), Sox9, proteoglycan-4 (PRG-4), and matrix metalloproteinases (MMP-3 and -13). There were statistically significant differences in GAG/DNA content between the stimulated versus the control group with highest levels in the combined stimulation group. Gene expression was significantly higher for combined stimulation groups versus static control for collagen 2/collagen 1 ratio and lower for MMP-13. Amongst other genes, a more chondrogenic phenotype was noticed in expression patterns for the stimulated groups. To conclude, there is an effect of electromagnetic and mechanical stimulation on chondrocytes seeded in a 3-D scaffold, resulting in improved extracellular matrix production. © 2013 Wiley Periodicals, Inc.

  13. Effects of electromagnetic radiation (bright light, extremely low-frequency magnetic fields, infrared radiation) on the circadian rhythm of melatonin synthesis, rectal temperature, and heart rate.

    Science.gov (United States)

    Griefahn, Barbara; Künemund, Christa; Blaszkewicz, Meinolf; Lerchl, Alexander; Degen, Gisela H

    2002-10-01

    Electromagnetic spectra reduce melatonin production and delay the nadirs of rectal temperature and heart rate. Seven healthy men (16-22 yrs) completed 4 permuted sessions. The control session consisted of a 24-hours bedrest at infrared radiation (65 degrees C) was applied from 5 pm to 1 am. Salivary melatonin level was determined hourly, rectal temperature and heart rate were continuously recorded. Melatonin synthesis was completely suppressed by light but resumed thereafter. The nadirs of rectal temperature and heart rate were delayed. The magnetic field had no effect. Infrared radiation elevated rectal temperature and heart rate. Only bright light affected the circadian rhythms of melatonin synthesis, rectal temperature, and heart rate, however, differently thus causing a dissociation, which might enhance the adverse effects of shiftwork in the long run.

  14. Study of mortality for cancer in the Municipalities of Quilmes and Berazategui. Period 1999 - 2003. Influence of extremely low frequency electromagnetic field

    International Nuclear Information System (INIS)

    Luccioli de Sobel, N.I.; Garcia, S.I.; De Pietri, D.

    2008-01-01

    This study is based on the claims reported by the neighbors of Berazategui as to an increased cancer incidence in population around Sobral Substation (located in Ezpeleta Locality, within the Municipality of Quilmes), associated to the possible influence of electromagnetic fields. Objective: To study the mortality by malign tumors presumably related to electromagnetic fields (EMF), especially breast, encephalic, lymphomas, myeloma and leukaemia cancer, in the populations of the localities within the Municipalities of Berazategui and Quilmes during the 2001-2003 period. Statistical Analysis: Calculation of the Adjusted Mortality Rate (AMR), Standardized Ratio of Mortality Rates (SRR) and Standardized Mortality Ratio (SMR), per cancer case according to single site, by sex, age and localization, Excess Cancer Index and Vulnerability Index as to the % of area affected by substations and high tension power lines. Results: Quilmes exhibits (AMR) per cancer, for men and women of 113,1 % 000 and 90,2 % 000 respectively, in comparison to those values observed in Berazategui: 113,8%000 and 86,6%000. In certain municipalities, the SRR showed a higher risk to die of selected site cancer as to the Province of Buenos Aires. The SMR in both municipalities and in Ezpeleta was below '1' in both sexes, determining a smaller number of deaths than those expected for men and women should they represent the specific mortality rates by age of the population in the Province of Buenos Aires and Argentina. There is no association between the increase in the number of selected cancer cases and the expansion of the area affected by the substations and/or high tension power lines. Discussion: Indicators used show no increase of mortality from cancer presumably linked to electromagnetic fields (EMF). More detailed studies are recommended in order to deepen analysis with geo referencing and term of residence of the deceased. (author)

  15. Similar Data Retrieval from Enormous Datasets on ELF/VLF Wave Spectrum Observed by Akebono

    Directory of Open Access Journals (Sweden)

    Y Kasahara

    2010-02-01

    Full Text Available As the total amount of data measured by scientific spacecraft is drastically increasing, it is necessary for researchers to develop new computation methods for efficient analysis of these enormous datasets. In the present study, we propose a new algorithm for similar data retrieval. We first discuss key descriptors that represent characteristics of the VLF/ELF waves observed by the Akebono spacecraft. Second, an algorithm for similar data retrieval is introduced. Finally, we demonstrate that the developed algorithm works well for the retrieval of the VLF spectrum with a small amount of CPU load.

  16. O-GlcNAc inhibits interaction between Sp1 and Elf-1 transcription factors

    International Nuclear Information System (INIS)

    Lim, Kihong; Chang, Hyo-Ihl

    2009-01-01

    The novel protein modification, O-linked N-acetylglucosamine (O-GlcNAc), plays an important role in various aspects of cell regulation. Although most of nuclear transcription regulatory factors are modified by O-GlcNAc, O-GlcNAc effects on transcription remain largely undefined yet. In this study, we show that O-GlcNAc inhibits a physical interaction between Sp1 and Elf-1 transcription factors, and negatively regulates transcription of placenta and embryonic expression oncofetal protein gene (Pem). These findings suggest that O-GlcNAc inhibits Sp1-mediated gene transcription possibly by interrupting Sp1 interaction with its cooperative factor.

  17. ELF - An experimental programme to quantify the effects of load follow and perturbated power histories

    International Nuclear Information System (INIS)

    Bairiot, H.; Hass, D.; Stora, J.P.

    1984-01-01

    Most of the ramp tests performed in national or international programmes have as main objective to define the fuel rod failure/survival limits, as a function of various parameters. Only a few of these experiments are sufficiently instrumented. The main feature of the ELF programme, described in this paper, consists in continuously measuring the cladding diameter during irradiation in OSIRIS of pre-irradiated PWR fuel rods, in order to provide strain relaxation data under various operating conditions. Power fluctuations during these OSIRIS irradiations are defined in order to obtain the conditioning and deconditioning kinetics of the fuel rods. (author)

  18. Modified two-body potential model to the 3He(α,γ)8B reaction at extremely low energies

    International Nuclear Information System (INIS)

    Igamov, S.B.; Santullaev, A.; Yarmukhamedov, R.

    2005-01-01

    Full text: A reliable estimation of rates of different nuclear astrophysical reactions A(α,γ)B responsible for light elements abundance is one of the most actual problem of the modern nuclear astrophysics. Solution of this problem is impossible without obtaining of rather low energy cross sections (or equivalently its astrophysical S-factor (AS) S Aa (E)) for such reactions as 3 He(α,γ) 8 B, 7 Be(p,γ) 8 B, etc. In the present work modified two-body potential approach allowing to determine both the asymptotic normalization constant (ANC) of the overlap integral for the bound wave function f the nucleus B in the (A+α)-channel C Aα;1.j (or respective nuclear vertex constant for the virtual decay B→A+α, where 1(j) is orbital (total) angular momentum of a particle α in the nucleus B=(A+α), and the AS S Aα (E) at the stellar energies (E≤25 keV) from an analysis of the analysis of the S exp (E) for the peripheral direct capture reaction A(α,γ)B is developed. The method involves two additional conditions that verify the peripheral character of the reaction under consideration and on it S(E) is expressed i the terms of ANC C Aα;1.j as Z Aα;1.j =C Aα;1.j 2 /b l +j 2 , where b lj is the single-particle ANC for the wave function of the bound B=(A+α) state calculated within the shell model using the phenomenological Woods-Saxon potential with the geometric parameters (a radius r 0 and a diffuseness a). The value of b lj strongly changes as a function (r 0 ,a)-pair is determined by variation of values of the parameters r 0 , and a in a wide physical acceptable range. The present method allows one to remove the model dependence of the calculated direct on S(E) on the geometric parameters r 0 , and a both for the two-body bound (A+α) state and the Aα-scattering state in minimum. The developed method has been applied to the analysis of the experimental S exp (E) of the direct capture 3 He(α,γ) 7 Be and 7 Be(p,γ) 8 B reactions at extremely low energies. By

  19. ELFE{alpha}DESY: an electron laboratory for Europe at DESY

    Energy Technology Data Exchange (ETDEWEB)

    Frois, B.; Brinkmann, R.; Kose, R.; Maidment, J.; Bruinsma, P.; Wu, Y.; Conto, J.M. de; Faure, J.; Gentner, M.; Husmann, D.; Tazzioli, F.

    1997-12-01

    ELFE is a project to develop a 15 to 30 GeV, high luminosity, continuous beam electron accelerator for scattering experiments from fixed nuclear targets. The goal is to explore the quark and gluon structure of matter by exclusive and semi-exclusive electron scattering from nuclei. The idea of integrating ELFE into TESLA facility is based on the fact that the superconducting linac is operated at a low duty cycle, about 0.4%, for the electron-positron collider mode and the machine is available for other tasks during the time between collider pulses. A fraction of the beam pulses produced by TESLA could be injected into the HERA ring until the ring is filled. The authors show that it is possible to extract the electrons from HERA used as a stretcher ring and produce a high luminosity quasi continuous beam suitable for nuclear physics experiments. The performances of the extracted beam in term of emittance, energy spread and duty factor have been evaluated. (N.T.).

  20. Situation and perspectives in refrigerating and air-conditioning. The point of view of Elf Atochem; Situation et perspectives en refrigeration et air conditionne. Point de vue d`Elf Atochem

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This paper is a series of transparencies which explains the engagements of Elf Atochem company in the replacement of chlorofluorocarbons (CFCs): development of HFCs, production of FORANE, safety and environmental criteria, main refrigerants and their application in new installations, perspectives in reconversion, replacement of R-22, CFC-12 and R-502 fluids with respect to their applications. (J.S.)

  1. The Deceiving ELF? Can Englsh fulfil the role of a Lingua Franca?

    Directory of Open Access Journals (Sweden)

    Richard Chapman

    2016-01-01

    Full Text Available Abstract – The debate which surrounds the role of English as a lingua franca has been lively and extensive over the last twenty years or so. Numerous conferences and specific publications in the field testify to the interest and importance that the question of the development of a possible international functional language has stimulated. The present article aims to critically reassess the claims made for ELF and, at the same time, highlight the profound significance of the issues the debate has raised. Discussion of ELF has touched upon the perception of linguistic diversity, (inaccuracy and variation, intelligibility and the potential functions of an international language. Other topics of profound importance that are part of the debate relate to the role of any language in creating and maintaining identity, enabling social mobility and empowering its users. Some criticisms of ELF proposals have been easily rebutted, but this paper aims to underline the serious linguistic and socio-linguistic aspects of the debate in order to emphasize the need for a theoretical underpinning to our understanding of how language can operate in the global environment. Clarification of what we can and cannot know about language change and behavior will also contribute to ideas as to future research in ELF but will also bring us to the conclusion that predictions of the future development of ELF are of little purpose beyond the curiosity value they may possess. Keywords: English1; lingua franca2; non-native speaker3.     Abstract– Il dibattito intorno al ruolo di inglese intesa come lingua franca è vivace e largo da almeno venti anni. Le conferenze e pubblicazioni specifiche sull’argomento sono numerose e sono testimone di quanto è interessante e importante la questione dello sviluppo di una lingua internazionale funzionale e utile. L’articolo qui presentato ha lo scopo di valutare a rivalutare le speranze che si sono formate per l’inglese come

  2. Extremely Low-Profile Circular Patch-Ring Antenna with A Shorting Via for Impedance Matching Improvement

    DEFF Research Database (Denmark)

    Zhang, Shuai; Syrytsin, Igor A.; Sørensen, Morten

    2017-01-01

    behavior. The designed antenna covers the Wi-Fi band of 2.4- 2.48 GHz with the realized gain of over 1.5 dBi and the thickness of 0.005 λ (λ is the wavelength of the lowest operating frequency in free space). Since the antenna is not sensitive to size of ground plane, it is suitable to be mounted...

  3. Through-container, extremely low concentration detection of multiple chemical markers of counterfeit alcohol using a handheld SORS device

    OpenAIRE

    Ellis, David; R, Eccles; Xu, Yun; J, Griffen; Muhamadali, H; P, Matousek; Goodall, I; Goodacre, Royston

    2017-01-01

    Major food adulteration incidents occur with alarming frequency and are episodic, with the latest incident, involving the adulteration of meat from 21 producers in Brazil supplied to 60 other countries, reinforcing this view. Food fraud and counterfeiting involves all types of foods, feed, beverages, and packaging, with the potential for serious health, as well as significant economic and social impacts. In the spirit drinks sector, counterfeiters often ‘recycle’ used genuine packaging, or em...

  4. Bespoke Language Teaching (BLT): A Proposal for a Theoretical Framework. the Case of EFL/ELF for Italians

    Science.gov (United States)

    Santipolo, Matteo

    2017-01-01

    This paper deals with the problems of teaching English as a foreign language (EFL) and as a lingua franca (ELF) in the Italian educational system and, in particular, with introducing language variation in the English class. After briefly illustrating how English teaching has changed in the last few decades, an outline is drawn of what happens in…

  5. Occupational exposure to electromagnetic fields and chronic diseases

    OpenAIRE

    Håkansson, Niclas

    2003-01-01

    This thesis consider two exposures from the electromagnetic spectrum extremely low-frequency magnetic fields (ELF MF) and ultraviolet (UV) radiation. ELF MF are the lowest and UV radiation ranges among the highest frequencies of non-ionizing radiation. The exposure prevalence of these fields is high in the general population. Most people are exposed daily to either or both types and potential health effects are of great concern. The aim of the thesis was to study occupationa...

  6. Como minimizar a lesão pulmonar no prematuro extremo: propostas Strategies to minimize lung injury in extremely low birth weight infants

    Directory of Open Access Journals (Sweden)

    Cleide Suguihara

    2005-03-01

    Full Text Available OBJETIVO: Apresentar uma revisão das principais causas da nova displasia broncopulmonar e as estratégias utilizadas para diminuir sua incidência nos prematuros extremos. FONTES DOS DADOS: Para essa revisão, pesquisas foram feitas na MEDLINE (1996 a outubro de 2004, no Cochrane Database, em resumos da Society for Pediatric Research e recentes conferências sobre o tema. SÍNTESE DOS DADOS: A tecnologia e os novos conhecimentos científicos têm aumentado significantemente a sobrevida de prematuros extremos. Esse aumento da sobrevida resultou em aumento da incidência de displasia broncopulmonar. Atualmente, a displasia broncopulmonar é mais freqüentemente observada em recém-nascidos OBJECTIVE: To review the main causes of new bronchopulmonary dysplasia and the strategies utilized to decrease its incidence in extremely low birth weight infants. DATA SOURCES: For this review a MEDLINE search from 1966 to October 2004, the Cochrane Database, abstracts from the Society for Pediatric Research and recent meetings on the topic were used. SUMMARY OF FINDINGS: The survival of extremely low birth weight infants has increased significantly due to improvement in both scientific knowledge and technology. This improvement in survival has therefore resulted in an increased incidence of bronchopulmonary dysplasia. The characteristics of bronchopulmonary dysplasia in extremely low birth weight infants, the so called "new" bronchopulmonary dysplasia are quite different from the classic bronchopulmonary dysplasia described by Northway. This new bronchopulmonary dysplasia has a multifactorial etiology, which includes volutrauma, atelectrauma, oxygen toxicity and lung inflammation. Therapy such as prenatal corticosteroids, exogenous surfactant, nasal continuous positive airway pressure, new mechanical ventilation modalities and gentle ventilation have been used in attempts to decrease lung injury severity. CONCLUSIONS: In order to prevent lung injury in

  7. Anomalous Signal Detection in ELF Band Electromagnetic Wave using Multi-layer Neural Network with Wavelet Decomposition

    Science.gov (United States)

    Itai, Akitoshi; Yasukawa, Hiroshi; Takumi, Ichi; Hata, Masayasu

    It is well known that electromagnetic waves radiated from the earth's crust are useful for predicting earthquakes. We analyze the electromagnetic waves received at the extremely low frequency band of 223Hz. These observed signals contain the seismic radiation from the earth's crust, but also include several undesired signals. Our research focuses on the signal detection technique to identify an anomalous signal corresponding to the seismic radiation in the observed signal. Conventional anomalous signal detections lack a wide applicability due to their assumptions, e.g. the digital data have to be observed at the same time or the same sensor. In order to overcome the limitation related to the observed signal, we proposed the anomalous signals detection based on a multi-layer neural network which is trained by digital data observed during a span of a day. In the neural network approach, training data do not need to be recorded at the same place or the same time. However, some noises, which have a large amplitude, are detected as the anomalous signal. This paper develops a multi-layer neural network to decrease the false detection of the anomalous signal from the electromagnetic wave. The training data for the proposed network is the decomposed signal of the observed signal during several days, since the seismic radiations are often recorded from several days to a couple of weeks. Results show that the proposed neural network is useful to achieve the accurate detection of the anomalous signal that indicates seismic activity.

  8. Enfants conçus avec une aide médicale dans la cohorte Elfe

    OpenAIRE

    Poulalhon, Claire

    2015-01-01

    Objectif : étudier les conditions entourant la naissance des enfants conçus avec une aide médicale, et explorer le rôle des facteurs sociaux et médicaux dans la prématurité et l’hypotrophie.Méthodes : l'analyse porte sur 9495 enfants de la cohorte Elfe, de terme supérieur à 33 semaines d'aménorrhée, singletons ou jumeaux, répartis en trois groupes selon leur contexte de conception, "traitement", "infertiles non traités" et "fertiles" (790, 1044 et 7661 enfants). Cinq champs ont été décrits (c...

  9. Genotoxicity and ELF-magnetic fields: a review through the micronucleus assay

    International Nuclear Information System (INIS)

    Alcaraz, M.; Andreu-Galvez, M.; Sanchez-Villalobos, J. M.; Achel, D. G.; Olmos, E.; Martinez-Hernandez, C. M.

    2012-01-01

    Thirty for (34) published studies, conducted from 1994 to the present to evaluate the genotoxic effect of magnetic fields using ELF-EMF and diagnostic resonance on humans by the micronucleus assay have been reviewed. some characteristics of the assay methods, their significance to genotoxicity and basic interpretations of the results of these assays are discussed. of the studies analysed 70.5% implicated genotoxic effects induced by these magnetic fields: 52.9% were due to exposure to magnetic fields only and 17,6% by exposure to magnetic fields in combination with some treatment types, resulting in additive or synergistic effect. Evidence exist to support the notion that exposure of humans to magnetic fields stimulates genotoxic effects, although the actual mechanisms of action or even the true human health consequences resulting from these exposure still remain unclear. (Author) 80 refs.

  10. ZWEI 'JAHRHUNDERTHOCHWASSER' IN ELF JAHREN - EIN VERGLEICH DER HOCHWASSEREREIGNISSE VON 2002 UND 2013 (IN DEUTSCHLAND

    Directory of Open Access Journals (Sweden)

    ANJA KLEINEBRAHN

    2014-05-01

    Full Text Available Zwei 'jahrhunderthochwasser' in elf jahren - ein vergleich der hochwasserereignisse von 2002 und 2013 (in Deutschland. Worldwide floods are among the most frequent and most momentous natural disasters. They occur in unpredictable intervals and dimensions and always bring particularly devastating or catastrophic impacts, if they get into contact with people or its uses. Within eleven years only Germany was affected of two so-called 'century-floods'. The expiry of extreme high water can be influenced by technical measures only up to a certain degree. It is therefore necessary to have a high protection from the effects of floods and to keep the impact as low as possible. Both being prepared as well as possible and being capable of acting for the case of emergency are corequisite. Flood protection is a longsome and s steadily continuing process. In dealing with the consequences of floods both political measures and the commitment and solidarity of the citizens were in demand.

  11. Features of Physical and Neuro-Psychological Development of Children with Low, Very Low and Extremely Low Birth Weight in Different Age Periods of Life

    Directory of Open Access Journals (Sweden)

    I. A. Deev

    2016-01-01

    Full Text Available Analysis of features of physical and neuro-psychological development of children with low, very low and extremely low birth weight in different age periods is carried out according to cohort studies of newborns with different gestational age and birth weight, presented in electronic databases PubMed and Medscape. It is revealed that the overwhelming number of children with low, very low and extremely low birth weight, gain physical and neuro- psychological development impairments, hearing and vision disorders of varying severity, violation of motor function, intelligence and cognitive skills infringement in an older age. In this regard, it is actual not only to develop new neonatal reanimation and intensive care technologies, but also to ensure adequate prevention of preterm birth in the group of women with a high degree of perinatal risk. All this will further allow preventing increase in children with disabling conditions number among premature infants.

  12. Extremely Low Genetic Diversity Indicating the Endangered Status of Ranodon sibiricus (Amphibia: Caudata) and Implications for Phylogeography

    Science.gov (United States)

    Wang, Xiu-Ling; Sun, Jian-Yun; Xue, Yan; Zhang, Peng; Zhou, Hui; Qu, Liang-Hu

    2012-01-01

    Background The Siberian salamander (Ranodon sibiricus), distributed in geographically isolated areas of Central Asia, is an ideal alpine species for studies of conservation and phylogeography. However, there are few data regarding the genetic diversity in R. sibiricus populations. Methodology/Principal Findings We used two genetic markers (mtDNA and microsatellites) to survey all six populations of R. sibiricus in China. Both of the markers revealed extreme genetic uniformity among these populations. There were only three haplotypes in the mtDNA, and the overall nucleotide diversity in the mtDNA was 0.00064, ranging from 0.00000 to 0.00091 for the six populations. Although we recovered 70 sequences containing microsatellite repeats, there were only two loci that displayed polymorphism. We used the approximate Bayesian computation (ABC) method to study the demographic history of the populations. This analysis suggested that the extant populations diverged from the ancestral population approximately 120 years ago and that the historical population size was much larger than the present population size; i.e., R. sibiricus has experienced dramatic population declines. Conclusion/Significance Our findings suggest that the genetic diversity in the R. sibiricus populations is the lowest among all investigated amphibians. We conclude that the isolation of R. sibiricus populations occurred recently and was a result of recent human activity and/or climatic changes. The Pleistocene glaciation oscillations may have facilitated intraspecies genetic homogeneity rather than enhanced divergence. A low genomic evolutionary rate and elevated inbreeding frequency may have also contributed to the low genetic variation observed in this species. Our findings indicate the urgency of implementing a protection plan for this endangered species. PMID:22428037

  13. Method of moving frames to solve time-dependent Maxwell's equations on anisotropic curved surfaces: Applications to invisible cloak and ELF propagation

    Science.gov (United States)

    Chun, Sehun

    2017-07-01

    Applying the method of moving frames to Maxwell's equations yields two important advancements for scientific computing. The first is the use of upwind flux for anisotropic materials in Maxwell's equations, especially in the context of discontinuous Galerkin (DG) methods. Upwind flux has been available only to isotropic material, because of the difficulty of satisfying the Rankine-Hugoniot conditions in anisotropic media. The second is to solve numerically Maxwell's equations on curved surfaces without the metric tensor and composite meshes. For numerical validation, spectral convergences are displayed for both two-dimensional anisotropic media and isotropic spheres. In the first application, invisible two-dimensional metamaterial cloaks are simulated with a relatively coarse mesh by both the lossless Drude model and the piecewisely-parametered layered model. In the second application, extremely low frequency propagation on various surfaces such as spheres, irregular surfaces, and non-convex surfaces is demonstrated.

  14. Setting research strategy on electromagnetic-field pollution of Ecuador

    International Nuclear Information System (INIS)

    Becerra, C.A.

    1989-01-01

    General population and occupational groups are being exposed to electromagnetic field (EMF) nonionizing radiation that come from all electric or electronic equipment that work either with extremely low frequency (ELF) or radiofrequency (RF) fields. This preoccupation has generated research and regulation plans in some countries int he world, in order to set a clear configuration of bioeffects and other environmental implications derived from exposures to ELF/RF EMF

  15. Prospects of hadron and quark physics with electromagnetic probes. Proceedings of the second ELFE workshop on Hadronic Physics

    International Nuclear Information System (INIS)

    D'Hose, N.; Frois, B.; Guichon, P.A.M.; Pire, B.; Van de Wiele, J.

    1996-01-01

    The last three days of the second ELFE workshop on confinement physics were devoted to the results of the work during the past year on the update and improvement of the physics case, the feasibility of the ELFE at DESY project (which combines the HERA ring used as a stretcher and a low duty factor 25 GeV electron linac which could be either a section of the TESLA collider or the injector of the foreseen short wave length free electron laser) as well as the development of the detectors. The participations have been decided into 5 copies: inclusive and semi-inclusive reactions; real photon physics, exclusive reactions; color transparency; detectors. (author)

  16. Prospects of hadron and quark physics with electromagnetic probes. Proceedings of the second ELFE workshop on Hadronic Physics

    Energy Technology Data Exchange (ETDEWEB)

    D' Hose, N; Frois, B; Guichon, P A.M. [CEA Saclay, 91 - Gif-sur-Yvette (France). Dept. d' Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l' Instrumentation Associee; Pire, B [Ecole Polytechnique, 91 - Palaiseau (France). Centre de Physique Theorique; Van de Wiele, J [Institut de Physique Nucleaire, 91 - Orsay (France). Division de Recherche Experimentale

    1996-07-01

    The last three days of the second ELFE workshop on confinement physics were devoted to the results of the work during the past year on the update and improvement of the physics case, the feasibility of the ELFE at DESY project(which combines the HERA ring used as a stretcher and a low duty factor 25 GeV electron linac which could be either a section of the TESLA collider or the injector of the foreseen short wave length free electron laser) as well as the development of the detectors. The participations have been decided into 5 copies: inclusive and semi-inclusive reactions; real photon physics, exclusive reactions; color transparency; detectors. (author)

  17. Reduced brachial flow-mediated vasodilation in young adult ex extremely low birth weight preterm: a condition predictive of increased cardiovascular risk?

    Science.gov (United States)

    Bassareo, P P; Fanos, V; Puddu, M; Demuru, P; Cadeddu, F; Balzarini, M; Mercuro, G

    2010-10-01

    Sporadic data present in literature report how preterm birth and low birth weight constitute the risk factors for the development of cardiovascular diseases in later life. To assess the presence of potential alterations to endothelial function in young adults born preterm at extremely low birth weight (Cesarea, Israel). Endothelial function was significantly reduced in ex-ELBW subjects compared to C (1.94 +/- 0.37 vs. 2.68 +/- 0.41, p < 0.0001). Moreover, this function correlated significantly with gestational age (r = 0.56, p < 0.0009) and birth weight (r = 0.63, p < 0.0001). The results obtained reveal a significant decrease in endothelial function of ex-ELBW subjects compared to controls, underlining a probable correlation with preterm birth and low birth weight. Taken together, these results suggest that an ELBW may underlie the onset of early circulatory dysfunction predictive of increased cardiovascular risk.

  18. Differences in extreme low salinity timing and duration differentially affect eastern oyster (Crassostrea virginica) size class growth and mortality in Breton Sound, LA

    Science.gov (United States)

    LaPeyre, Megan K.; Eberline, Benjamin S.; Soniat, Thomas M.; La Peyre, Jerome F.

    2013-01-01

    Understanding how different life history stages are impacted by extreme or stochastic environmental variation is critical for predicting and modeling organism population dynamics. This project examined recruitment, growth, and mortality of seed (25–75 mm) and market (>75 mm) sized oysters along a salinity gradient over two years in Breton Sound, LA. In April 2010, management responses to the Deepwater Horizon oil spill resulted in extreme low salinity (25 °C) significantly and negatively impacted oyster recruitment, survival and growth in 2010, while low salinity (25 °C). With increasing management of our freshwater inputs to estuaries combined with predicted climate changes, how extreme events affect different life history stages is key to understanding variation in population demographics of commercially important species and predicting future populations.

  19. A case report of a patient carrying CYP2C9*3/4 genotype with extremely low warfarin dose requirement.

    Science.gov (United States)

    Lee, Soo Youn; Nam, Myung Hyun; Kim, June Soo; Kim, Jong Won

    2007-06-01

    We report a case of intolerance to warfarin dosing due to impaired drug metabolism in a patient with CYP2C9*3/*4. A 73-yr-old woman with atrial fibrilation was taking warfarin. She attained a high prothrombin time international normalized ratio (INR) at the standard doses during the induction of anticoagulation and extremely low dose of warfarin (6.5 mg/week) was finally chosen to reach the target INR. Genotyping for CYP2C9 revealed that this patient had a genotype CYP2C9*3/*4. This is the first Korean compound heterozygote for CYP2C9*3 and *4. This case suggests the clinical usefulness of pharmacogenetic testing for individualized dosage adjustments of warfarin.

  20. Modulation of brassinosteroid-regulated gene expression by jumonji domain-containing proteins ELF6 and REF6 in Arabidopsis

    OpenAIRE

    Yu, Xiaofei; Li, Li; Li, Lei; Guo, Michelle; Chory, Joanne; Yin, Yanhai

    2008-01-01

    Plant steroid hormones, brassinosteroids (BRs), are of great importance for plant growth and development. BRs signal through a cell surface receptor kinase, BRI1, and a GSK3-like kinase, BIN2, to regulate the BES1/BZR1 family of transcription factors, which directly bind to target gene promoters to activate or repress gene expression and mediate BR responses. To understand how BES1 regulates target gene expression, we identified two BES1-interacting proteins, ELF6 (early flowering 6) and its ...

  1. ELF/VLF wave propagation at subauroral latitudes: Conjugate observation between the ground and Van Allen Probes

    Czech Academy of Sciences Publication Activity Database

    Martinez‐Calderon, C.; Shiokawa, K.; Miyoshi, Y.; Keika, K.; Ozaki, M.; Schofield, I.; Connors, M.; Kletzing, C.; Hanzelka, Miroslav; Santolík, Ondřej; Kurth, W. S.

    2016-01-01

    Roč. 121, č. 6 (2016), s. 5384-5393 ISSN 2169-9380 R&D Projects: GA ČR(CZ) GA14-31899S Institutional support: RVO:68378289 Keywords : QP * conjugate event * VLF/ELF * propagation * time delay * ray tracing Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.733, year: 2016 http://onlinelibrary.wiley.com/doi/10.1002/2015JA022264/full

  2. Extremely low penetrance of deafness associated with the mitochondrial 12S rRNA mutation in 16 Chinese families: Implication for early detection and prevention of deafness

    International Nuclear Information System (INIS)

    Dai Pu; Liu Xin; Han Dongyi; Qian Yaping; Huang Deliang; Yuan Huijun; Li Weiming; Yu Fei; Zhang Ruining; Lin Hongyan; He Yong; Yu Youjun; Sun Quanzhu; Qin Huaiyi; Li Ronghua; Zhang Xin; Kang Dongyang; Cao Juyang; Young Wieyen; Guan Minxin

    2006-01-01

    Mutations in mitochondrial DNA (mtDNA) have been found to be associated with sensorineural hearing loss. We report here the clinical, genetic, and molecular characterization of 16 Chinese pedigrees (a total of 246 matrilineal relatives) with aminoglycoside-induced impairment. Clinical evaluation revealed the variable phenotype of hearing impairment including audiometric configuration in these subjects, although these subjects share some common features: being bilateral and sensorineural hearing impairment. Strikingly, these Chinese pedigrees exhibited extremely low penetrance of hearing loss, ranging from 4% to 18%, with an average of 8%. In particular, nineteen of 246 matrilineal relatives in these pedigrees had aminoglycoside-induced hearing loss. Mutational analysis of the mtDNA in these pedigrees showed the presence of homoplasmic 12S rRNA A1555G mutation, which has been associated with hearing impairment in many families worldwide. The extremely low penetrance of hearing loss in these Chinese families carrying the A1555G mutation strongly supports the notion that the A1555G mutation itself is not sufficient to produce the clinical phenotype. Children carrying the A1555G mutation are susceptible to the exposure of aminoglycosides, thereby inducing or worsening hearing impairment, as in the case of these Chinese families. Using those genetic and molecular approaches, we are able to diagnose whether children carry the ototoxic mtDNA mutation. Therefore, these data have been providing valuable information and technology to predict which individuals are at risk for ototoxicity, to improve the safety of aminoglycoside therapy, and eventually to decrease the incidence of deafness

  3. Demodulation effect is observed in neurones by exposure to low frequency modulated microwaves

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Bruzon, R N; Figols, T; Azanza, M J [Laboratorio de Magnetobiologia, Departamento de Anatomia e Histologia Humanas, Facultad de Medicina, Universidad de Zaragoza (Spain); Moral, A del, E-mail: naogit@yahoo.co [Laboratorio de Magnetismo de Solidos, Departamento de Fisica de Materia Condensada and Instituto de Ciencia de Materiales de Aragon, Universidad de Zaragoza and CSIC (Spain)

    2010-01-01

    Neurones exposure to a microwave (carrier f{sub c}=13.6 GHz; power P {approx_equal} 5 mW; H{sub o} {approx_equal} 0.10 Am{sup -1} = 1.25 mOe; E{sub 0} {approx_equal} 3.5 V/m; {Delta}T {approx_equal} 0.01{sup 0}C; SAR: 3.1x10{sup -3} - 5.8x10{sup -3} W/Kg) EMF amplitude modulated by ELF-AC field (frequency, f{sub m}= 0-100 Hz) shows no electrophysiological effect under the carrier MF alone, but {sup f}requency resonances: at 2, 4, 8, 12, 16, 50, 100 Hz: demodulation effect. Resonances appear when applied ELF-MF is close to a dominant characteristic frequency of the neurone impulse Fourier spectrum. This is an interesting result considering that ELF-MF modulating RF or MW in the range of human EEG could induce frequency-resonant effects on exposed human brain.

  4. A simplified theory of ELF propagation in the Earth-ionosphere transmission line

    International Nuclear Information System (INIS)

    Booker, H.G.

    1980-01-01

    An approximate theory of ELF propagation in the Earth-ionosphere transmission line is developed by combining the reflection theory of Booker and Lefeuvre with Greifinger and Greifinger's treatment of the effect of ionization below the level of reflection. The theory allows for the influence of the Earth's magnetic field, for reflection from the gradient on the under side of the D-region (or, at night, of a ledge below the E-region), for reflection from the gradient on the underside of the E-region and for reflection from the gradient on the topside of the E-region. The procedure is to compare local vertical gradient with local wavelength, thereby classifying altitude into intervals where the gradient is high and ones where it is low. Where the gradient is low, the phase-integral treatment is adequate. An interval where the gradient is high may, to a first approximation, be replaced by a discontinuity. The amount of the discontinuity is the difference between the refractive indices at the top and bottom of the interval of high gradient, judged in relation to local wavelength. It is then a matter of combining reflections from the several discontinuities. This requires calculation of the complex phase-changes between the discontinuities. But there are the intervals where the phase-integral treatment is available. To a better approximation, there is a non-zero phase change associated with an interval of high gradient. The method for incorporating this is described. (author)

  5. A health examination of railway high-voltage substation workers exposed to ELF electromagnetic fields.

    Science.gov (United States)

    Baroncelli, P; Battisti, S; Checcucci, A; Comba, P; Grandolfo, M; Serio, A; Vecchia, P

    1986-01-01

    This is a cross-sectional survey on the health conditions of railways workers active in 258 interconnection and conversion substations all over Italy. Measurements performed in both kinds of substations operating at 220 kV have shown that maximum levels of the electric field strength and of the magnetic flux density at 50 Hz are of the order of 5 kV/m and 15 microT, respectively. Three subject groups, differently exposed (1, 10, 20 h/week), and an unexposed control group, for a total number of 627 workers, constitute the population at study. All subjects underwent a general medical examination, laboratory investigations, and a series of selected examinations relative to three systems (nervous, cardiovascular, and haematopoietic) considered at higher risk. No differences have been found between the exposed and the control groups. It is concluded that workers exposed to ELF electromagnetic fields of moderate strength do not show the presence of clear effects on their state of health.

  6. Introduction of percutaneous-tunneled transfontanellar external ventricular drainage in the management of hydrocephalus in extremely low-birth-weight infants.

    Science.gov (United States)

    Zucchelli, Mino; Lefosse, Mariella; Corvaglia, Luigi; Martini, Silvia; Sandri, Fabrizio; Soffritti, Silvia; Ancora, Gina; Mammoliti, Palma; Gargano, Giancarlo; Galassi, Ercole

    2016-07-01

    OBJECTIVE Hydrocephalus treatment in extremely low-birth-weight (ELBW) infants still represents a challenge for the pediatric neurosurgeon, particularly when the patient weighs far less than 1000 g. In such cases, the benefits in terms of neurological outcome following early treatment do not always outweigh the surgical risks, especially considering the great difference in the surgical risk before patient weight increases. To assess the efficacy and reliability of a percutaneous-tunneled, transfontanellar external ventricular drain (PTTEVD) in ELBW infants, the authors started a new protocol for the early surgical treatment of hydrocephalus. METHODS Ten cases of posthemorrhagic hydrocephalus (PHH) in ELBW infants (5 cases CSF leakage (due to insufficient CSF removal). In another patient Enterococcus in the CSF sample was detected the day after abdominal surgery with ileostomy (infection resolved with intrathecal vancomycin). One patient died of Streptococcus sepsis, a systemic infection existing prior to drain placement that never resolved. One patient had Pseudomonas aeruginosa sepsis prior to drain insertion; a PTTEVD was implanted, the infection resolved, and the hydrocephalus was treated in the same way as with a traditional EVD, while the advantages of a quick, minimally invasive, bedside procedure were maintained. Once a patient reached 1 kg in weight, when necessary, a ventriculoperitoneal shunt was implanted and the PTTEVD was removed. CONCLUSIONS The introduction of PTTEVD placement in our standard protocol for the management of PHH has proved to be a wise option for small patients.

  7. High rate of symptomatic cytomegalovirus infection in extremely low gestational age preterm infants of 22-24 weeks' gestation after transmission via breast milk.

    Science.gov (United States)

    Mehler, Katrin; Oberthuer, André; Lang-Roth, Ruth; Kribs, Angela

    2014-01-01

    Very immature preterm infants are at risk of developing symptomatic or severe infection if cytomegalovirus is transmitted via breast milk. It is still a matter of debate whether human cytomegalovirus (HCMV) infection may lead to long-term sequelae. We hypothesized that symptomatic and severe HCMV infection transmitted via breast milk affects extremely immature infants at a very high rate. In 2012, untreated breast milk was fed to extremely low birth weight infants after parental informed consent was obtained. We retrospectively analyzed data on HCMV infection of infants born in 2012 between 22 and 24 weeks of gestation. 17 infants were born to HCMV IgG-seropositive mothers. 11 (65%) of these were diagnosed with symptomatic infection. In all cases, thrombocytopenia was the reason to analyze the infant's urine. HCMV infection was diagnosed at a median time of 12 weeks after birth. In 5 (45%) infants, thrombocytopenia was the only symptom and resolved without antiviral therapy or platelet transfusion. 6 (55%) infants developed sepsis-like disease with mildly elevated CRP values and showed signs of respiratory failure. 3 (27%) were able to be stabilized on CPAP, 3 (27%) had to be intubated and mechanically ventilated. 4 children were treated with ganciclovir and/or valganciclovir. 55% failed otoacoustic emissions and/or automated auditory brainstem response testing at discharge. In very immature infants born at the border of viability and suffering from multiple preexisting problems, HCMV infection may trigger a severe deterioration of the clinical course. © 2013 S. Karger AG, Basel.

  8. Near infrared imaging-guided photodynamic therapy under an extremely low energy of light by galactose targeted amphiphilic polypeptide micelle encapsulating BODIPY-Br2.

    Science.gov (United States)

    Liu, Le; Ruan, Zheng; Li, Tuanwei; Yuan, Pan; Yan, Lifeng

    2016-10-18

    Near infrared (NIR) imaging-guided photodynamic therapy (PDT) is attractive, especially the utilization of one dye as both a photosensitizer and fluorescent probe, and the as-synthesized BODIPY-Br 2 molecule is a candidate. Here, a galactose targeted amphiphilic copolymer of a polypeptide was synthesized and its micelles work as nanocarriers for BODIPY for targeting the NIR imaging-guided PDT of hepatoma cancer cells. At the same time, BODIPY could light up the cytoplasm for real-time imaging and kill cancer cells when the light was switched on. In vitro tests performed on both HepG2 and HeLa cells confirmed that the as-prepared PMAGP-POEGMA-PLys-B micelles showed efficient cell suppression of the cells with galactose receptors in the presence of light under an extremely low energy density (6.5 J cm -2 ). This protocol highlights the potential of polypeptides as biodegradable carriers for NIR image-guided and confined targeting photodynamic therapy.

  9. Factors associated with tuberculosis cases in Semarang District, Indonesia: case-control study performed in the area where case detection rate was extremely low.

    Science.gov (United States)

    Rahayu, Sri Ratna; Katsuyama, Hironobu; Demura, Masashi; Katsuyama, Midori; Ota, Yoko; Tanii, Hideji; Higashi, Tomomi; Semadi, Ngakan Putu Djaja; Saijoh, Kiyofumi

    2015-07-01

    Indonesia is ranked as the 4th highest contributor to tuberculosis (TB) in the world. Semarang District in Central Java displays extremely low case detection rate (CDR), possibly contributing to the local prevalence of TB. A case-control study was performed to explore the factors that cause such low CDR. We recruited 129 TB cases and 83 controls that visited the same centers and were not diagnosed with TB. The cases had 7.5 ± 2.3 symptoms/person on average, indicating the delay in diagnosis because the controls only displayed 1.0 ± 1.7. The multiple logistic regression analysis comparing the cases/controls extracted following factors as a risk to have TB: farmer, close contact with TB patients, ignorance of whether Bacillus Calmette-Guérin (BCG) was accepted or no, smoking, low income, a lot of people living in the same room, irregular hand wash before meals, not wash hands after blow, soil floor, and no sunlight and no ventilation in the house. Neither the cases nor the controls knew the symptoms and how to avoid TB infection, which probably caused the delay in diagnosis. It is difficult to change the current living conditions. Thus, the amendment of the community-based education program of TB seems to be required.

  10. SDSS J074511.56+194926.5: Discovery of a metal-rich and tidally distorted extremely low mass white dwarf

    Energy Technology Data Exchange (ETDEWEB)

    Gianninas, A.; Barber, Sara D.; Kilic, Mukremin [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States); Hermes, J. J.; Harrold, Samuel T. [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States); Brown, Warren R.; Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden St., Cambridge, MA 02138 (United States); Dufour, P., E-mail: alexg@nhn.ou.edu [Département de Physique, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7 (Canada)

    2014-02-01

    We present the discovery of an unusual, tidally distorted extremely low mass white dwarf (WD) with nearly solar metallicity. Radial velocity measurements confirm that this is a compact binary with an orbital period of 2.6975 hr and a velocity semi-amplitude of K = 108.7 km s{sup –1}. Analysis of the hydrogen Balmer lines yields an effective temperature of T {sub eff} = 8380 K and a surface gravity of log g = 6.21 that in turn indicate a mass of M = 0.16 M {sub ☉} and a cooling age of 4.2 Gyr. In addition, a detailed analysis of the observed metal lines yields abundances of log (Mg/H) = –3.90, log (Ca/H) = –5.80, log (Ti/H) = –6.10, log (Cr/H) = –5.60, and log (Fe/H) = –4.50, similar to the sun. We see no evidence of a debris disk from which these metals would be accreted, though the possibility cannot entirely be ruled out. Other potential mechanisms to explain the presence of heavy elements are discussed. Finally, we expect this system to ultimately undergo unstable mass transfer and merge to form a ∼0.3-0.6 M {sub ☉} WD in a few Gyr.

  11. Acute Responses to Diuretic Therapy in Extremely Low Gestational Age Newborns: Results from the Prematurity and Respiratory Outcomes Program Cohort Study.

    Science.gov (United States)

    Blaisdell, Carol J; Troendle, James; Zajicek, Anne

    2018-06-01

    To determine if daily respiratory status improved more in extremely low gestational age (GA) premature infants after diuretic exposure compared with those not exposed in modern neonatal intensive care units. The Prematurity and Respiratory Outcomes Program (PROP) was a multicenter observational cohort study of 835 extremely premature infants, GAs of 23 0/7 -28 6/7 weeks, enrolled in the first week of life from 13 US tertiary neonatal intensive care units. We analyzed the PROP study daily medication and respiratory support records of infants ≤34 weeks postmenstrual age. We determined whether there was a temporal association between the administration of diuretics and an acute change in respiratory status in premature infants in the neonatal intensive care unit, using an ordered categorical ranking of respiratory status. Infants in the diuretic exposed group of PROP were of lower mean GA and lower mean birth weight (P respiratory status before receiving diuretics) that the exposed infants were on a higher level of respiratory support was significantly greater (OR, >1) for each day after the initial day of diuretic exposure. Our analysis did not support the ability of diuretics to substantially improve the extremely premature infant's respiratory status. Further study of both safety and efficacy of diuretics in this setting are warranted. Clinicaltrials.gov: NCT01435187. Published by Elsevier Inc.

  12. Systemic Candidiasis in Extremely Low Birthweight (ELBW) Neonates Despite the Routine Use of Topical Miconazole Prophylaxis: Trends, Risk Factors and Outcomes over an 11-Year Period.

    Science.gov (United States)

    Sriram, Bhavani; Agarwal, Pratibha K; Tee, Nancy W S; Rajadurai, Victor S

    2014-05-01

    This study aims to determine the incidence, trends of systemic candidiasis and meningitis in extremely low birthweight (ELBW) neonates (candidiasis and meningitis over an 11-year period (1997 to 2007). Matched case control analyses were performed to determine the risk factors and comorbidities which were severe intraventricular haemorrhage (IVH), severe retinopathy of prematurity (ROP), patent ductus arteriosus (PDA) requiring treatment, necrotising enterocolitis (NEC), chronic lung disease (CLD) and cholestatic jaundice. Mortality and end organ involvement secondary to systemic candidiasis were identified as adverse outcomes. Of the 757 ELBW neonates, 51 (6.7%) had evidence of systemic candidiasis with a significant 3-fold increase in trend noted in 2007 as compared against 1997 (12.1% vs 3.8%) (RR 1.2, 95% CI, 1.06 to 1.36, P candidiasis (0% in 1997 vs 7.1% in 2007, RR 1.40, 95% CI, 1.04 to 1.25, P = 0.005). On logistic regression analysis, decreasing gestational age was an independent risk factor for systemic candidiasis (OR 2.0, 95% CI, 1.52 to 2.63, P candidiasis despite routine use of topical miconazole prophylaxis is of concern and future studies comparing the use of systemic fl uconazole versus oral nystatin may need to be considered.

  13. Role of prophylactic surgical ligation of patent ductus arteriosus in extremely low birth weight infants: Systematic review and implications for clinical practice

    International Nuclear Information System (INIS)

    Mosalli, Rafat; AlFaleh, Khalid; Paes, Bosco

    2009-01-01

    To investigate the effectiveness and safety of prophylactic surgical ligation of patent ductus arteriosus (PDA) on mortality and morbidity of preterm infants weighing less than 1000 g at birth. The study conducted a systematic search of available database from 1996-2008. Retrieved articles were assessed for eligibility and data was abstracted independently by two reviewers. Decisions to include studies for review and the methodological quality of included studies were asssessed in duplicate based on predetermined criteria. No language restrictions were applied. Only one eligible study that enrolled 84 extremely low birth weight infants was identified. Prophylactic surgical ligation of PDA resulted in a statistically significant reduction of severe stage II or III necrotizing enterocolitis, [RR 0.25, 95% CI (0.08, 0.83), P value 0.02, number needed to treat 5]. The study, however, found no statistically significant difference in mortality, intraventricular hemorrhage, bronchopulmonary dysplasia, and retinopathy of prematurity. Current evidence does not support the use of prophylactic surgical ligation of PDA in the management of the preterm infants

  14. Development, analysis, and evaluation of a commercial software framework for the study of Extremely Low Probability of Rupture (xLPR) events at nuclear power plants.

    Energy Technology Data Exchange (ETDEWEB)

    Kalinich, Donald A.; Helton, Jon Craig; Sallaberry, Cedric M.; Mattie, Patrick D.

    2010-12-01

    Sandia National Laboratories (SNL) participated in a Pilot Study to examine the process and requirements to create a software system to assess the extremely low probability of pipe rupture (xLPR) in nuclear power plants. This project was tasked to develop a prototype xLPR model leveraging existing fracture mechanics models and codes coupled with a commercial software framework to determine the framework, model, and architecture requirements appropriate for building a modular-based code. The xLPR pilot study was conducted to demonstrate the feasibility of the proposed developmental process and framework for a probabilistic code to address degradation mechanisms in piping system safety assessments. The pilot study includes a demonstration problem to assess the probability of rupture of DM pressurizer surge nozzle welds degraded by primary water stress-corrosion cracking (PWSCC). The pilot study was designed to define and develop the framework and model; then construct a prototype software system based on the proposed model. The second phase of the project will be a longer term program and code development effort focusing on the generic, primary piping integrity issues (xLPR code). The results and recommendations presented in this report will be used to help the U.S. Nuclear Regulatory Commission (NRC) define the requirements for the longer term program.

  15. Neonatal pain-related stress, functional cortical activity and visual-perceptual abilities in school-age children born at extremely low gestational age.

    Science.gov (United States)

    Doesburg, Sam M; Chau, Cecil M; Cheung, Teresa P L; Moiseev, Alexander; Ribary, Urs; Herdman, Anthony T; Miller, Steven P; Cepeda, Ivan L; Synnes, Anne; Grunau, Ruth E

    2013-10-01

    Children born very prematurely (pain-related stress during neonatal intensive care has been proposed to contribute to altered neurocognitive development in these children. Due to critical periods in the development of thalamocortical systems, the immature brain of infants born at extremely low gestational age (ELGA; pain. In a cohort of school-age children followed since birth we assessed relations between functional brain activity measured using magnetoencephalogragy (MEG), visual-perceptual abilities and cumulative neonatal pain. We demonstrated alterations in the spectral structure of spontaneous cortical oscillatory activity in ELGA children at school-age. Cumulative neonatal pain-related stress was associated with changes in background cortical rhythmicity in these children, and these alterations in spontaneous brain oscillations were negatively correlated with visual-perceptual abilities at school-age, and were not driven by potentially confounding neonatal variables. These findings provide the first evidence linking neonatal pain-related stress, the development of functional brain activity, and school-age cognitive outcome in these vulnerable children. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  16. Association of Antegrade Pulmonary Artery Diastolic Velocity with Spontaneous Closure of the Patent Ductus Arteriosus in Extremely Low-Birth-Weight Infants.

    Science.gov (United States)

    Weiss, Dawn M; Kaiser, Jeffrey R; Swearingen, Christopher; Malik, Sadia; Sachdeva, Ritu

    2015-11-01

    This study aims to determine echocardiographic parameters associated with spontaneous patent ductus arteriosus (PDA) closure in extremely low-birth-weight (ELBW) infants. Retrospective demographic review and analysis of echocardiograms from 189 ELBW infants with suspected and confirmed hemodynamically significant PDA identified on an initial echocardiogram was performed. Comparison of echocardiographic parameters was made between infants with spontaneous closure versus those who received treatment. The mean birth weight (787 ± 142 vs. 724 ± 141 g, p = 0.04) and gestational age (27.4 ± 2.8 vs. 26.2 ± 1.6 weeks, p = 0.03) were higher in the spontaneous closure versus the treatment group. Antegrade pulmonary artery (PA) diastolic velocity was lower in infants with spontaneous PDA closure versus those who received treatment (0.15 ± 0.06 vs. 0.22 ± 0.12 m/s, p = 0.009). Heavier and more mature ELBW infants with a lower antegrade PA diastolic velocity were likely to have spontaneous closure of the PDA. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  17. Targeting 2.5 versus 4 g/kg/day of amino acids for extremely low birth weight infants: a randomized clinical trial.

    Science.gov (United States)

    Burattini, Ilaria; Bellagamba, Maria Paola; Spagnoli, Cristina; D'Ascenzo, Rita; Mazzoni, Nadia; Peretti, Anna; Cogo, Paola E; Carnielli, Virgilio P

    2013-11-01

    To compare the effect of 2.5 vs 4 g/kg/d of amino acid (AA) in parenteral nutrition of extremely low birth weight infants on metabolic tolerance, short-term growth, and neurodevelopment. One hundred thirty-one infants with birth weight between 500 and 1249 g were randomized to 2.5 (standard AA [SAA] group) or 4 (high AA [HAA] group) g/kg/d AA intake, with equal nonprotein energy. The primary outcome was body size at 36 weeks. One hundred thirty-one patients were randomized and 114 analyzed (58 SAA group and 56 HAA group). Study groups had similar demographics and clinical characteristics. Elevated blood urea (BU >70 mg/dL = BU nitrogen >32.6 mg/dL) occurred in 24% vs 59% (P = .000) and hyperglycemia (>175 mg/dL) in 34% vs 11% (P = .003) of the SAA and HAA patients, respectively. Body weight, length, and head circumference at 36 weeks and 2 years were similar between groups. Bayley Scales of Infant and Toddler Development, Third Edition score was 94 ± 13 in the SAA group and 97 ± 15 in the HAA group (P = .35). The HAA group had higher BU levels and better glucose control. An extra 8 g/kg of AA over the first 10 days of life did not improve growth and neurodevelopment. Copyright © 2013 Mosby, Inc. All rights reserved.

  18. U.S. Nuclear Regulatory Commission Extremely Low Probability of Rupture pilot study : xLPR framework model user's guide.

    Energy Technology Data Exchange (ETDEWEB)

    Kalinich, Donald A.; Sallaberry, Cedric M.; Mattie, Patrick D.

    2010-12-01

    For the U.S. Nuclear Regulatory Commission (NRC) Extremely Low Probability of Rupture (xLPR) pilot study, Sandia National Laboratories (SNL) was tasked to develop and evaluate a probabilistic framework using a commercial software package for Version 1.0 of the xLPR Code. Version 1.0 of the xLPR code is focused assessing the probability of rupture due to primary water stress corrosion cracking in dissimilar metal welds in pressurizer surge nozzles. Future versions of this framework will expand the capabilities to other cracking mechanisms, and other piping systems for both pressurized water reactors and boiling water reactors. The goal of the pilot study project is to plan the xLPR framework transition from Version 1.0 to Version 2.0; hence the initial Version 1.0 framework and code development will be used to define the requirements for Version 2.0. The software documented in this report has been developed and tested solely for this purpose. This framework and demonstration problem will be used to evaluate the commercial software's capabilities and applicability for use in creating the final version of the xLPR framework. This report details the design, system requirements, and the steps necessary to use the commercial-code based xLPR framework developed by SNL.

  19. The macrophage activation marker sCD163 combined with markers of the Enhanced Liver Fibrosis (ELF) score predicts clinically significant portal hypertension in patients with cirrhosis

    DEFF Research Database (Denmark)

    Sandahl, T D; McGrail, R; Møller, H J

    2016-01-01

    BACKGROUND: Noninvasive identification of significant portal hypertension in patients with cirrhosis is needed in hepatology practice. AIM: To investigate whether the combination of sCD163 as a hepatic inflammation marker and the fibrosis markers of the Enhanced Liver Fibrosis score (ELF) can...... predict portal hypertension in patients with cirrhosis. METHODS: We measured sCD163 and the ELF components (hyaluronic acid, tissue inhibitor of metalloproteinase-1 and procollagen-III aminopeptide) in two separate cohorts of cirrhosis patients that underwent hepatic vein catheterisation. To test...... the predictive accuracy we developed a CD163-fibrosis portal hypertension score in an estimation cohort (n = 80) and validated the score in an independent cohort (n = 80). A HVPG ≥10 mmHg was considered clinically significant. RESULTS: Both sCD163 and the ELF components increased in a stepwise manner...

  20. Klucel™ EF and ELF polymers for immediate-release oral dosage forms prepared by melt extrusion technology.

    Science.gov (United States)

    Mohammed, Noorullah Naqvi; Majumdar, Soumyajit; Singh, Abhilasha; Deng, Weibin; Murthy, Narasimha S; Pinto, Elanor; Tewari, Divya; Durig, Thomas; Repka, Michael A

    2012-12-01

    The objective of this research work was to evaluate Klucel™ hydroxypropylcellulose (HPC) EF and ELF polymers, for solubility enhancement as well as to address some of the disadvantages associated with solid dispersions. Ketoprofen (KPR), a Biopharmaceutics Classification System class II drug with poor solubility, was utilized as a model compound. Preliminary thermal studies were performed to confirm formation of a solid solution/dispersion of KPR in HPC matrix and also to establish processing conditions for hot-melt extrusion. Extrudates pelletized and filled into capsules exhibited a carrier-dependent release with ELF polymer exhibiting a faster release. Tablets compressed from milled extrudates exhibited rapid release owing to the increased surface area of the milled extrudate. Addition of mannitol (MNT) further enhanced the release by forming micro-pores and increasing the porosity of the extrudates. An optimized tablet formulation constituting KPR, MNT, and ELF in a 1:1:1 ratio exhibited 90% release in 15 min similar to a commercial capsule formulation. HPC polymers are non-ionic hydrophilic polymers that undergo polymer-chain-length-dependent solubilization and can be used to enhance solubility or dissolution rate of poorly soluble drugs. Dissolution/release rate could be tailored for rapid-release applications by selecting a suitable HPC polymer and altering the final dosage form. The release obtained from pellets was carrier-dependent and not drug-dependent, and hence, such a system can be effectively utilized to address solubility or precipitation issues with poorly soluble drugs in the gastrointestinal environment.

  1. Simultaneous observations of quasi-periodic ELF/VLF wave emissions and electron precipitation by DEMETER satellite: A case study

    Czech Academy of Sciences Publication Activity Database

    Hayosh, Mykhaylo; Pasmanik, D. L.; Demekhov, A. G.; Santolík, Ondřej; Parrot, M.; Titova, E. E.

    2013-01-01

    Roč. 118, č. 7 (2013), s. 4523-4533 ISSN 2169-9380 R&D Projects: GA ČR(CZ) GAP209/11/2280; GA MŠk LH12231 Institutional support: RVO:68378289 Keywords : quasi-periodic ELF/VLF emission s in the magnetosphere * wave-particle interactions * demeter spacecraft measurements * whistler-mode waves Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 3.440, year: 2013 http://onlinelibrary.wiley.com/doi/10.1002/jgra.50179/abstract

  2. ELF/VLF signatures of sprite-producing lightning discharges observed during the 2005 EuroSprite campaign

    DEFF Research Database (Denmark)

    Greenberg, E.; Price, C.; Yair, Y.

    2009-01-01

    ) discharges had peak current intensities between +8 and +130 kA whereas their charge moment changes (CMC) ranged from 500 to 3500 C km. Furthermore, the peak current reported by the Météorage lightning network are well correlated with the amplitudes of the VLF bursts, while showing poor correlation......%) an ELF transient was not associated with sprite occurrence, suggesting that long continuing current of tens of ms may not always be a necessary condition for sprite production, a finding which influences the estimation of the global sprite rate based on Schumann resonance (SR) measurements....

  3. CMCTS stabilized Fe3O4 particles with extremely low toxicity as highly efficient near-infrared photothermal agents for in vivo tumor ablation

    Science.gov (United States)

    Shen, Song; Kong, Fenfen; Guo, Xiaomeng; Wu, Lin; Shen, Haijun; Xie, Meng; Wang, Xinshi; Jin, Yi; Ge, Yanru

    2013-08-01

    With the potential uses of photothermal therapy (PTT) in cancer treatment with excellent efficacy, and the growing concerns about the nanotoxicity of hyperthermia agents such as carbon nanotubes and gold-based nanomaterials, the importance of searching for a biocompatible hyperthermia agent cannot be emphasized too much. In this work, a novel promising hyperthermia agent employing magnetic Fe3O4 particles with fairly low toxicity was proposed. This hyperthermia agent showed rapid heat generation under NIR irradiation. After modification with carboxymethyl chitosan (CMCTS), the obtained Fe3O4@CMCTS particles could disperse stably in PBS and serum without any aggregation. The modification of CMCTS could decrease the adsorption of bovine serum albumin (BSA) and improve the cellular uptake. In a comparative study with hollow gold nanospheres (HAuNS), Fe3O4@CMCTS particles exhibited a comparable photothermal effect and fairly low cytotoxicity. The in vivo magnetic resonance (MR) images of mice revealed that by attaching a magnet to the tumor, Fe3O4@CMCTS particles accumulated in the tumor after intravenous injection and showed a low distribution in the liver. After being exposed to a 808 nm laser for 5 min at a low power density of 1.5 W cm-2, the tumors on Fe3O4@CMCTS-injected mice reached a temperature of ~52 °C and were completely destroyed. Thus, a kind of multifunctional magnetic nanoparticle with extremely low toxicity and a simple structure for simultaneous MR imaging, targeted drug delivery and photothermal therapy can be easily fabricated.With the potential uses of photothermal therapy (PTT) in cancer treatment with excellent efficacy, and the growing concerns about the nanotoxicity of hyperthermia agents such as carbon nanotubes and gold-based nanomaterials, the importance of searching for a biocompatible hyperthermia agent cannot be emphasized too much. In this work, a novel promising hyperthermia agent employing magnetic Fe3O4 particles with fairly low

  4. Analysis of the 7Be (P, γ) 8B reaction at extremely low energies within the modified two-body potential approach

    International Nuclear Information System (INIS)

    Sanetullaev, A.; Igamov, S.B.; Yarmukhamedov, R.

    2004-01-01

    Full text: Obtaining the extremely low energy cross sections for the reaction 7 Be(p,γ ) 8 B is of great interest for a reliable estimation of the rate of this reaction, which is crucial for an accurate determination of the solar neutrino flux. At present, in current literature, there is a rather wide spread in estimation of this rate (see, for instance, Ref. [1] and references therein). In this work, the modified two-body potential approach for analysis of the astrophysical S- factor S(E) for the peripheral direct radiative capture 7 Be(p,γ ) 8 B reaction of astrophysical interest is applied, in which the additional conditions of verification of the peripheral character of the reaction under consideration are formulated. The method involves the information on the asymptotic normalization coefficient (ANC) for the virtual decay 8 B → 7 Be+p and allows one to exclude the model dependence of the calculated direct astrophysical S-factor S(E) on the geometric parameters (radius r 0 and diffuseness a) of the adopted Woods-Saxon potential, which is usually used for calculations both for the two-body ( 7 Be+p)-bound state and for the 7 Be p -scattering state. The rather precise experimental astrophysical S-factor, S exp (E), in the energy range 100 7 Be(p,γ ) 8 B reaction, measured recently by the authors of Ref. [1] is used for the analysis. It is demonstrated that at extremely low energies this reaction is strongly peripheral and the measured S exp (E) can be used as an independent source of getting the information about the ANC. The new information about values of the ANC is obtained with an estimation of the weighted mean errors for them, which involves both the experimental errors of the S exp (E), and uncertainty of the method not exceeding 4%. The extracted value of the ANC is equal to C 2 =C 2 1/2 +C 2 3/2 =5.68± 0.15 fm -1 , where the indices show the value total angular momentum of the proton in the (p+ 7 Be)-bound state of 8 B. It was also demonstrated

  5. Determination of extremely low 236U/238U isotope ratios in environmental samples by sector-field inductively coupled plasma mass spectrometry using high-efficiency sample introduction

    International Nuclear Information System (INIS)

    Boulyga, Sergei F.; Heumann, Klaus G.

    2006-01-01

    A method by inductively coupled plasma mass spectrometry (Icp-Ms) was developed which allows the measurement of 236 U at concentration ranges down to 3 x 10 -14 g g -1 and extremely low 236 U/ 238 U isotope ratios in soil samples of 10 -7 . By using the high-efficiency solution introduction system APEX in connection with a sector-field ICP-MS a sensitivity of more than 5000 counts fg -1 uranium was achieved. The use of an aerosol desolvating unit reduced the formation rate of uranium hydride ions UH + /U + down to a level of 10 -6 . An abundance sensitivity of 3 x 10 -7 was observed for 236 U/ 238 U isotope ratio measurements at mass resolution 4000. The detection limit for 236 U and the lowest detectable 236 U/ 238 U isotope ratio were improved by more than two orders of magnitude compared with corresponding values by alpha spectrometry. Determination of uranium in soil samples collected in the vicinity of Chernobyl nuclear power plant (NPP) resulted in that the 236 U/ 238 U isotope ratio is a much more sensitive and accurate marker for environmental contamination by spent uranium in comparison to the 235 U/ 238 U isotope ratio. The ICP-MS technique allowed for the first time detection of irradiated uranium in soil samples even at distances more than 200 km to the north of Chernobyl NPP (Mogilev region). The concentration of 236 U in the upper 0-10 cm soil layers varied from 2 x 10 -9 g g -1 within radioactive spots close to the Chernobyl NPP to 3 x 10 -13 g g -1 on a sampling site located by >200 km from Chernobyl

  6. Determination of extremely low (236)U/(238)U isotope ratios in environmental samples by sector-field inductively coupled plasma mass spectrometry using high-efficiency sample introduction.

    Science.gov (United States)

    Boulyga, Sergei F; Heumann, Klaus G

    2006-01-01

    A method by inductively coupled plasma mass spectrometry (ICP-MS) was developed which allows the measurement of (236)U at concentration ranges down to 3 x 10(-14)g g(-1) and extremely low (236)U/(238)U isotope ratios in soil samples of 10(-7). By using the high-efficiency solution introduction system APEX in connection with a sector-field ICP-MS a sensitivity of more than 5,000 counts fg(-1) uranium was achieved. The use of an aerosol desolvating unit reduced the formation rate of uranium hydride ions UH(+)/U(+) down to a level of 10(-6). An abundance sensitivity of 3 x 10(-7) was observed for (236)U/(238)U isotope ratio measurements at mass resolution 4000. The detection limit for (236)U and the lowest detectable (236)U/(238)U isotope ratio were improved by more than two orders of magnitude compared with corresponding values by alpha spectrometry. Determination of uranium in soil samples collected in the vicinity of Chernobyl nuclear power plant (NPP) resulted in that the (236)U/(238)U isotope ratio is a much more sensitive and accurate marker for environmental contamination by spent uranium in comparison to the (235)U/(238)U isotope ratio. The ICP-MS technique allowed for the first time detection of irradiated uranium in soil samples even at distances more than 200 km to the north of Chernobyl NPP (Mogilev region). The concentration of (236)U in the upper 0-10 cm soil layers varied from 2 x 10(-9)g g(-1) within radioactive spots close to the Chernobyl NPP to 3 x 10(-13)g g(-1) on a sampling site located by >200 km from Chernobyl.

  7. Evidence for an Invasive Aphid “Superclone”: Extremely Low Genetic Diversity in Oleander Aphid (Aphis nerii) Populations in the Southern United States

    Science.gov (United States)

    Harrison, John Scott; Mondor, Edward B.

    2011-01-01

    Background The importance of genetic diversity in successful biological invasions is unclear. In animals, but not necessarily plants, increased genetic diversity is generally associated with successful colonization and establishment of novel habitats. The Oleander aphid, Aphis nerii, though native to the Mediterranean region, is an invasive pest species throughout much of the world. Feeding primarily on Oleander (Nerium oleander) and Milkweed (Asclepias spp.) under natural conditions, these plants are unlikely to support aphid populations year round in the southern US. The objective of this study was to describe the genetic variation within and among US populations of A. nerii, during extinction/recolonization events, to better understand the population ecology of this invasive species. Methodology/Principal Findings We used five microsatellite markers to assess genetic diversity over a two year period within and among three aphid populations separated by small (100 km) and large (3,700 km) geographic distances on two host plant species. Here we provide evidence for A. nerii “superclones”. Genotypic variation was absent in all populations (i.e., each population consisted of a single multilocus genotype (MLG) or “clone”) and the genetic composition of only one population completely changed across years. There was no evidence of sexual reproduction or host races on different plant species. Conclusions/Significance Aphis nerii is a well established invasive species despite having extremely low genetic diversity. As this aphid appears to be obligatorily asexual, it may share more similarities with clonally reproducing invasive plants, than with other animals. Patterns of temporal and geographic genetic variation, viewed in the context of its population dynamics, have important implications for the management of invasive pests and the evolutionary biology of asexual species. PMID:21408073

  8. Extremely low penetrance of hearing loss in four Chinese families with the mitochondrial 12S rRNA A1555G mutation

    International Nuclear Information System (INIS)

    Young Wieyen; Zhao Lidong; Qian Yaping; Wang Qiuju; Li Ning; Greinwald, John H.; Guan Minxin

    2005-01-01

    Mutations in mitochondrial DNA (mtDNA) have been found to be associated with sensorineural hearing loss. We report here the clinical, genetic, and molecular characterization of four Chinese pedigrees with aminoglycoside-induced and nonsyndromic hearing impairment. Clinical evaluation revealed the variable phenotype of hearing impairment including audiometric configuration in these subjects, although these subjects share some common features: bilateral and sensorineural hearing impairment. Strikingly, these Chinese pedigrees exhibited extremely low penetrance of hearing loss (5.2%, 4.8%, 4.2%, and 13.3%, respectively, and with an average 8% penetrance). In particular, four of all five affected matrilineal relatives of these pedigrees had aminoglycoside-induced hearing loss. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the distinct sets of mtDNA polymorphism, in addition to the identical homoplasmic A1555G mutation, associated with hearing impairment in many families from different genetic backgrounds. The fact that mtDNA of those pedigrees belonged to different haplogroups R9a, N9a, D4a, and D4 suggested that the A1555G mutation occurred sporadically and multiplied through evolution of the mtDNA in China. However, there was the absence of functionally significant mutations in tRNA and rRNAs or secondary LHON mutations in these Chinese families. These data imply that the nuclear background or/and mitochondrial haplotype may not play a significant role in the phenotypic expression of the A1555G mutation in these Chinese pedigrees. However, aminoglycoside appears to be a major modifier factor for the phenotypic manifestation of the A1555G mutation in these Chinese families

  9. Evidence for an invasive aphid "superclone": extremely low genetic diversity in Oleander aphid (Aphis nerii populations in the southern United States.

    Directory of Open Access Journals (Sweden)

    John Scott Harrison

    2011-03-01

    Full Text Available The importance of genetic diversity in successful biological invasions is unclear. In animals, but not necessarily plants, increased genetic diversity is generally associated with successful colonization and establishment of novel habitats. The Oleander aphid, Aphis nerii, though native to the Mediterranean region, is an invasive pest species throughout much of the world. Feeding primarily on Oleander (Nerium oleander and Milkweed (Asclepias spp. under natural conditions, these plants are unlikely to support aphid populations year round in the southern US. The objective of this study was to describe the genetic variation within and among US populations of A. nerii, during extinction/recolonization events, to better understand the population ecology of this invasive species.We used five microsatellite markers to assess genetic diversity over a two year period within and among three aphid populations separated by small (100 km and large (3,700 km geographic distances on two host plant species. Here we provide evidence for A. nerii "superclones". Genotypic variation was absent in all populations (i.e., each population consisted of a single multilocus genotype (MLG or "clone" and the genetic composition of only one population completely changed across years. There was no evidence of sexual reproduction or host races on different plant species.Aphis nerii is a well established invasive species despite having extremely low genetic diversity. As this aphid appears to be obligatorily asexual, it may share more similarities with clonally reproducing invasive plants, than with other animals. Patterns of temporal and geographic genetic variation, viewed in the context of its population dynamics, have important implications for the management of invasive pests and the evolutionary biology of asexual species.

  10. Long-term effects of peer victimization on social outcomes through the fourth decade of life in individuals born at normal or extremely low birthweight.

    Science.gov (United States)

    Day, Kimberly L; Van Lieshout, Ryan J; Vaillancourt, Tracy; Saigal, Saroj; Boyle, Michael H; Schmidt, Louis A

    2017-09-01

    Exposure to early adversity is known to have deleterious effects on brain-behaviour relations across the lifespan and across a range of domains. Here, we tested a cumulative risk hypothesis of adult social functioning and health outcomes in the fourth decade of life, using the oldest known longitudinally followed cohort of survivors of extremely low birthweight (ELBW; 2,500 g) participants. In the combined sample, peer victimization was associated with lower likelihood of having children and household income, poorer family functioning and self-esteem, more loneliness and chronic health conditions, less social support, and increased likelihood for contact with police. Moderation analyses indicated that among ELBW survivors, compared to their NBW counterparts, victimization was more strongly associated with being convicted of a crime and with having chronic health conditions. These findings highlight the negative long-term impact of peer victimization on all children and that some outcomes may be differentially affected by prenatal and early post-natal environments. Statement of contribution What is already known on this subject Exposure to early adversity has deleterious effects on brain-behaviour relations across the lifespan. Extremely premature children have higher rates of exposure to adversities, including peer victimization. Peer victimization is associated with adverse outcomes in adulthood in those born at term. What does this study add? Victimization negatively impacts the social outcomes of those born extremely premature and at term into adulthood. Associations appear to be affected by individual differences in prenatal and early post-natal environments. Intervention is crucial when peer victimization occurs in children at risk, as well as those typically developing. © 2016 The British Psychological Society.

  11. Neurodevelopmental outcome at 5 years of age of a national cohort of extremely low birth weight infants who were born in 1996-1997.

    Science.gov (United States)

    Mikkola, Kaija; Ritari, Niina; Tommiska, Viena; Salokorpi, Teija; Lehtonen, Liisa; Tammela, Outi; Pääkkönen, Leena; Olsen, Päivi; Korkman, Marit; Fellman, Vineta

    2005-12-01

    Increasing survival of extremely low birth weight (ELBW; birth weight infants raises a concern regarding the risks of adverse long-term outcome such as cognitive dysfunction. Few studies have reported long-term follow-up of representative regional cohorts. The objective of this study was to assess the 5-year outcome of a prospectively followed national ELBW infant cohort. Of all live-born ELBW infants (n = 351) who were delivered in the 2-year period 1996-1997 in Finland, 206 (59%) survived until the age of 5 years. Of these, 103 were born at infants who were born at memory values of NEPSY assessment were significantly poorer compared with normal population means. Four percent needed a hearing aid, and 30% had ophthalmic findings. Of 21 children who had been treated with laser/cryo for retinopathy of prematurity, 17 (81%) had abnormal ophthalmic findings. Of the whole cohort, 41 (20%) exhibited major disabilities, 38 (19%) exhibited minor disabilities, and 124 (61%) showed development with no functional abnormalities but subtle departures from the norm. Only 53 (26%) of the total ELBW infant cohort were classified to have normal outcome excluding any abnormal ophthalmic, auditory, neurologic, or developmental findings. Being small for gestational age at birth was associated with suboptimal growth at least until age 5. Only one fourth of the ELBW infants were classified as normally developed at age 5. The high rate of cognitive dysfunction suggests an increased risk for learning difficulties that needs to be evaluated at a later age. Extended follow-up should be the rule in outcome studies of ELBW infant cohorts to elucidate the impact of immaturity on school achievement and social behavior later in life.

  12. Correlation of denitrification-accepted fraction of electrons with NAD(P)H fluorescence for Pseudomonas aeruginosa performing simultaneous denitrification and respiration at extremely low dissolved oxygen conditions.

    Science.gov (United States)

    Chen, Fan; Xia, Qing; Ju, Lu-Kwang

    2004-01-01

    In cystic fibrosis airway infection, Pseudomonas aeruginosa forms a microaerobic biofilm and undergoes significant physiological changes. It is important to understand the bacterium's metabolism at microaerobic conditions. In this work, the culture properties and two indicators (the denitrification-accepted e- fraction and an NAD(P)H fluorescence fraction) for the culture's "fractional approach" to a fully anaerobic denitrifying state were examined in continuous cultures with practically zero DO but different aeration rates. With decreasing aeration, specific OUR decreased while specific NAR and NIR increased and kept Y(ATP/S) relatively constant. P. aeruginosa thus appeared to effectively compensate for energy generation at microaerobic conditions with denitrification. At the studied dilution rate of 0.06 h(-1), the maximum specific OUR was 2.8 mmol O2/g cells-h and the Monod constant for DO, in the presence of nitrate, was extremely low (Y(X/S) increased significantly (from 0.24 to 0.34) with increasing aeration, attributed to a roughly opposite trend of Y(ATP/X) (ATP generation required for cell growth). As for the denitrification-accepted e- fraction and the fluorescence fraction, both decreased with increasing aeration as expected. The two fractions, however, were not directly proportional. The fluorescence fraction changed more rapidly than the e- fraction at very low aeration rates, whereas the opposite was true at higher aeration. The results demonstrated the feasibility of using online NAD(P)H fluorescence to monitor sensitive changes of cellular physiology and provided insights to the shift of e- -accepting mechanisms of P. aeruginosa under microaerobic conditions.

  13. Solar storm effects during Saint Patrick's Days in 2013 and 2015 on the Schumann resonances measured by the ELF station at Sierra Nevada (Spain)

    Science.gov (United States)

    Salinas, A.; Toledo-Redondo, S.; Navarro, E. A.; Fornieles-Callejón, J.; Portí, J. A.

    2016-12-01

    The effects of solar storms occurring during the days 17 to 19 March 2013 and 2015, St. Patrick's Day intervals, on Schumann resonances (SRs) have been studied. To do this, the experimental data recorded by the Juan Antonio Morente extremely low frequency station located at Sierra Nevada, Spain, have been processed in order to obtain hourly averaged information on the first three resonance modes. Results are compared with monthly averages of the SR data for each hour to detect deviations from the regular behavior. Evidence of significant changes in the peak amplitudes and frequencies of the SRs have been identified in the station's measurements and related to the coronal mass ejection impact in the magnetosphere, detected by in situ plasma measurements onboard spacecraft in the solar wind. However, the complicated nature of the Schumann resonances, dependent on multiple variables and subject to multiple unavoidable interferences (e.g., lightning or human radio sources), in conjunction with the complex magnetosphere-ionosphere-atmosphere coupling processes, makes it difficult to conclude that the observed deviations are exclusively due to the solar events mentioned. Results extracted from only two solar events cannot be considered as conclusive, and therefore, independent comparison with results reported by other research would seem advisable in future works on this subject.

  14. Presentation of the project MobiKids Communication technologies, environmental exposures and risk of brain tumors in young people; Presentacion del proyecto MobiKids: Tecnologias de la comunicacion, exposiciones ambientales y riesgo de tumores cerebrales en gente joven

    Energy Technology Data Exchange (ETDEWEB)

    Cardis, E.; Alguacil, J.; Aragones, N.; Morales, M.; Carretero, G.; Ferreras, E.; Kinci, L.; Kogevinas, M.; Pollan, M.; Solis, R.; Vriheid, M.; Zumel, A.

    2011-07-01

    MOBI-Kids, an international study coordinated by CREAL, Barcelona, aims to assess the possible relationship between exposure in children and adolescents to electromagnetic fields (EMF) from communication technologies (RF - and extremely low frequency - ELF) and the risk of developing a brain tumor. It also investigated the effects of other risk factors, including environmental exposures in childhood and in utero.

  15. Committee on Interagency Radiation Research and Policy Coordination (CIRRPC). Seventh annual report

    International Nuclear Information System (INIS)

    Young, A.L.

    1991-01-01

    In 1990--91 CIRRPC's program included efforts to improve interagency coordination on ionizing radiation risk assessments, a review of the reported health risks to humans from exposure to extremely low- frequency electric and magnetic fields (ELF/EMF), and increased coordination with national and international organizations such as NCRP and ICRP

  16. Presentation of the project MobiKids Communication technologies, environmental exposures and risk of brain tumors in young people

    International Nuclear Information System (INIS)

    Cardis, E.; Alguacil, J.; Aragones, N.; Morales, M.; Carretero, G.; Ferreras, E.; Kinci, L.; Kogevinas, M.; Pollan, M.; Solis, R.; Vriheid, M.; Zumel, A.

    2011-01-01

    MOBI-Kids, an international study coordinated by CREAL, Barcelona, aims to assess the possible relationship between exposure in children and adolescents to electromagnetic fields (EMF) from communication technologies (RF - and extremely low frequency - ELF) and the risk of developing a brain tumor. It also investigated the effects of other risk factors, including environmental exposures in childhood and in utero.

  17. Low frequency electrostatic modes in a magnetized dusty plasma

    International Nuclear Information System (INIS)

    Salimullah, M.; Hassan, M.H.A.

    1991-09-01

    The dispersion properties of low frequency electrostatic modes in a dusty plasma in the presence of a static homogeneous magnetic field are examined. It is found that the presence of the dust particles and the static magnetic field have significant effects on the dispersion relations. For the parallel propagation the electrostatic mode is slightly modified by the magnetic field for the ion acoustic branch. A new longitudinal mode arises at the extreme low frequency limit, which is unaffected by the magnetic field for the parallel propagation. For the transverse propagation the ion acoustic mode is not affected by the magnetic field. However, the undamped extreme low frequency mode is significantly modified by the presence of the magnetic field for the propagation transverse to the direction of the magnetic field. (author). 23 refs

  18. Comparison of the low-frequency magnetic field effects on bacteria Escherichia coli, Leclercia adecarboxylata and Staphylococcus aureus

    Czech Academy of Sciences Publication Activity Database

    Fojt, Lukáš; Strašák, Luděk; Vetterl, Vladimír; Šmarda, J.

    2004-01-01

    Roč. 63, 1-2 (2004), s. 337-341 ISSN 1567-5394 R&D Projects: GA ČR GA310/01/0816; GA AV ČR IBS5004107; GA AV ČR IAA4004404 Institutional research plan: CEZ:AV0Z5004920 Keywords : low-frequency electromagnetic field * ELF magnetic fields * bacteria Subject RIV: BO - Biophysics Impact factor: 2.261, year: 2004

  19. Major enhancement of extra-low-frequency radiation by increasing the high-frequency heating wave power in electrojet modulation

    International Nuclear Information System (INIS)

    Kuo, S.P.; Lee, S.H.; Kossey, Paul

    2002-01-01

    Extra-low-frequency (ELF) wave generation by modulated polar electrojet currents is studied. The amplitude-modulated high-frequency (HF) heating wave excites a stimulated thermal instability to enhance the electrojet current modulation by the passive Ohmic heating process. Inelastic collisions of electrons with neutral particles (mainly due to vibrational excitation of N 2 ) damp nonlinearly this instability, which is normally saturated at low levels. However, the electron's inelastic collision loss rate drops rapidly to a low value in the energy regime from 3.5 to 6 eV. As the power of the modulated HF heating wave exceeds a threshold level, it is shown that significant electron heating enhanced by the stimulated thermal instability can indeed cause a steep drop in the electron inelastic collision loss rate. Consequently, this instability saturates at a much higher level, resulting to a near step increase (of about 10-13 dB, depending on the modulation wave form) in the spectral intensity of ELF radiation. The dependence of the threshold power of the HF heating wave on the modulation frequency is determined

  20. Neurodevelopmental sequelae in premature newborns with extremely low weight and with very low weight at two years of age who left the Neonatal Intensive Care Unit of the Hospital Nacional Edgardo Rebagliati Martins 2009-2014

    Directory of Open Access Journals (Sweden)

    Carmen Fernández Sierra

    2017-02-01

    Full Text Available Objective: The purpose of this study is to describe the neurodevelopmental sequelae in premature newborns with extremely low weight and with very low weight at two years of age who left the Neonatal Intensive Care Unit of the Hospital Nacional Edgardo Rebagliati Martins. Materials and methods: A descriptive, retrospective, cross-sectional study in a population of 190 premature newborns with extremely low weight and with very low weight born from January 2009 to June 2014 who left the Neonatal Intensive Care Unit and took part in the follow-up program. The psychomotor development, sensorineural hearing loss, retinopathy of prematurity, presence of cerebral palsy and convulsive syndrome were assessed. Results: The average weight at birth was 1,180.53 ± 212.40 grams with a gestational age of 29.86 ± 2.33 weeks, and 51.58% of the newborns were male. Forty-two point six three percent (42.63% of the premature newborns with very low weight showed retardation of psychomotor development; 25.26%, retinopathy; 13.68%, sensorineural hearing loss; 3.68%, cerebral palsy; and 3.68%, convulsive syndrome. Fifty-two point two seven percent (52.27% of the premature newborns with extremely low weight showed retardation of psychomotor development; 50%, retinopathy; 15.91%, sensorineural hearing loss; and 2.27%, convulsive syndrome. Conclusions: Retardation of psychomotor development and retinopathy were the most important complications shown by premature newborns with extremely low weight and with very low weight at two years of age.

  1. 2002 results: TotalFinaElf makes a ''much better performance'' than the overall international oil groups

    International Nuclear Information System (INIS)

    Salles, E.

    2003-01-01

    T. Desmarest, head of TotalFinaElf oil and gas company, has presented the 2002 results of his company in the particular context of a moving international oil situation (the Iraq crisis and the situation in Venezuela) with important consequences on markets. At the same time, the company decided to change its name into 'Total' and to adopt a new logo. The results show a 17% drop with respect to 2001 but a 10% increase of the production. The high rate of exploration successes has led to the discovery of about 1 billion of bpe with a 0.8 US$ cost per bpe, which represents the best performance of the 5 world oil majors. The rate of reserves renewal reached 151% (11.2 billions of bpe at the end of 2002). The downstream activities (refining/distribution and basic chemistry) encountered much more problems for various reasons: low economic growth, climate warmth, international instability etc.. (J.S.)

  2. Higher Order Analysis of Turbulent Changes Found in the ELF Range Electric Field Plasma Before Major Earthquakes

    Science.gov (United States)

    Kosciesza, M.; Blecki, J. S.; Parrot, M.

    2014-12-01

    We report the structure function analysis of changes found in electric field in the ELF range plasma turbulence registered in the ionosphere over epicenter region of major earthquakes with depth less than 40 km that took place during 6.5 years of the scientific mission of the DEMETER satellite. We compare the data for the earthquakes for which we found turbulence with events without any turbulent changes. The structure functions were calculated also for the Polar CUSP region and equatorial spread F region. Basic studies of the turbulent processes were conducted with use of higher order spectra and higher order statistics. The structure function analysis was performed to locate and check if there are intermittent behaviors in the ionospheres plasma over epicenter region of the earthquakes. These registrations are correlated with the plasma parameters measured onboard DEMETER satellite and with geomagnetic indices.

  3. Health effects of low frequency electric and magnetic fields

    International Nuclear Information System (INIS)

    1992-06-01

    The US Department of Labor and the President's Office of Science and Technology Policy (STP) requested that the Committee on interagency Radiation Research and Policy Coordination (CIRRPC) conduct an independent evaluation of the reported health effects from exposure to low-frequency electric and magnetic fields (ELF-EMF), especially reports of carcinogenesis and reproductive and neurophysiological effects focusing on frequencies which appeared to be of greatest public concern. Oak Ridge Associated Universities (ORAU) was tasked by the CIRRPC to oversee the review by a panel of independent, non-Federal, scientists. Following their review of over 1000 journal articles, the ORAU Panel concluded ''... that there is no convincing evidence ... to support the contention that exposure to ELF-EMF generated by sources such as household appliances, video display terminals (10 to 30 KHz), and local power lines (15 to 180 Hz) are demonstrable health hazards.'' Although the Panel noted that some biological effects produced by these fields may be of scientific interest and warrant consideration for future research, it concluded that ''... in the broad scope of research needs in basic science and health research, any health concerns over exposures to these fields should not receive a high priority.'' This executive summary outlines the panel's investigation

  4. Biological effect of non-ionizing radiations on microorganisms

    International Nuclear Information System (INIS)

    Shimizu, Kikuo; Yamamoto, Takayoshi; Nakaoka, Yasuo

    2000-01-01

    We studied the effect of extremely low frequency magnetic fields (ELF-MF) of 60-Hz and 500 mT on the growth and the mutation frequency of the budding yeast S.cerevisiae and on the behavior of the ciliate Paramecium multimicronucleatum. The growth rate and mutation frequencies of several strains of S.cerevisiae (wild type and radiation sensitive mutants, rad or rev) were examined but no significant difference was observed. Moreover, the behavior of P.multimicronucleatum under the ELF-MF was examined. When exposed to a vertical field of 0.6 T, the cells accumulated at the upper end of the cuvette. (author)

  5. Biological effect of non-ionizing radiations on microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Kikuo; Yamamoto, Takayoshi [Osaka Univ., Radioisotope Research Center, Suita, Osaka (Japan); Nakaoka, Yasuo [Osaka Univ., Graduate School of Engineering Science, Department of Biophysical Engineering, Toyonaka, Osaka (Japan)

    2000-05-01

    We studied the effect of extremely low frequency magnetic fields (ELF-MF) of 60-Hz and 500 mT on the growth and the mutation frequency of the budding yeast S.cerevisiae and on the behavior of the ciliate Paramecium multimicronucleatum. The growth rate and mutation frequencies of several strains of S.cerevisiae (wild type and radiation sensitive mutants, rad or rev) were examined but no significant difference was observed. Moreover, the behavior of P.multimicronucleatum under the ELF-MF was examined. When exposed to a vertical field of 0.6 T, the cells accumulated at the upper end of the cuvette. (author)

  6. Child leukaemia and low frequency electromagnetic fields

    International Nuclear Information System (INIS)

    Clavel, J.

    2009-01-01

    The author discusses the possible causes of child leukaemia: exposure to natural ionizing radiation (notably radon), to pesticides, and to hydrocarbons emitted by road traffic. Some studies suggested that an inadequate reaction of the immune system to an ordinary infection could result in leukaemia. Other factors are suspected, notably extremely low frequency electromagnetic fields, the influence of which is then discussed by the author. She evokes and discusses results of different investigations on this topic which have been published since the end of the 1970's. It appears that a distance less than 50 meters from high voltage lines or the vicinity of transformation stations may double the risk of child leukaemia

  7. Importância dos minerais na alimentação do pré-termo extremo Minerals in the nutrition of extremely low birth weight infants

    Directory of Open Access Journals (Sweden)

    Cleide E. P. Trindade

    2005-03-01

    Full Text Available OBJETIVO: Revisão crítica da literatura sobre os minerais cálcio, fósforo e microelementos na nutrição do pré-termo extremo, considerando a importância no crescimento, mineralização óssea e como componente de dietas. FONTES DOS DADOS: Utilizamos o banco de dados MEDLINE e o Cochrane Database of Systematic Reviews, de 1994 a 2004. Selecionamos artigos com enfoques originais, artigos de revisão e livros específicos. SÍNTESE DOS DADOS: As dificuldades na nutrição de prematuros extremos aumentam a freqüência de prematuros com restrição de crescimento, cujas conseqüências futuras estão para serem determinadas. Todavia, há pouca literatura sobre minerais, especialmente sobre micronutrientes na nutrição do pré-termo extremo, considerando-se o deficiente armazenamento e a importância destes em nutrição. O principal enfoque desta revisão foi sobre o cálcio e o fósforo na mineralização óssea e na suplementação em nutrição parenteral e enteral, bem como a avaliação crítica da nutrição pós-alta sobre a mineralização óssea. São abordadas as necessidades de micronutrientes, principalmente selênio e zinco, e a função antioxidante do selênio na provável prevenção de doenças do prematuro com atuação de radicais livres. CONCLUSÃO: Considerando os baixos estoques de minerais em prematuros extremos, há necessidade de mais pesquisas sobre minerais na nutrição destes prematuros para definir suas reais necessidades, os aspectos metabólicos, bem como aplicar os conhecimentos na formulação de dietas que permitam prevenir quadros de deficiência e conseqüências a longo prazo. Ainda há controvérsias sobre a influência de fórmulas pós-alta sobre a evolução da doença óssea da prematuridade.OBJECTIVE: To review the literature on the role of calcium, phosphorus and trace elements in the nutrition of extremely low birth weight infants, considering their importance for metabolism, bone mineralization

  8. Curly arrows meet electron density transfers in chemical reaction mechanisms: from electron localization function (ELF) analysis to valence-shell electron-pair repulsion (VSEPR) inspired interpretation.

    Science.gov (United States)

    Andrés, Juan; Berski, Sławomir; Silvi, Bernard

    2016-07-07

    Probing the electron density transfers during a chemical reaction can provide important insights, making possible to understand and control chemical reactions. This aim has required extensions of the relationships between the traditional chemical concepts and the quantum mechanical ones. The present work examines the detailed chemical insights that have been generated through 100 years of work worldwide on G. N. Lewis's ground breaking paper on The Atom and the Molecule (Lewis, G. N. The Atom and the Molecule, J. Am. Chem. Soc. 1916, 38, 762-785), with a focus on how the determination of reaction mechanisms can be reached applying the bonding evolution theory (BET), emphasizing how curly arrows meet electron density transfers in chemical reaction mechanisms and how the Lewis structure can be recovered. BET that combines the topological analysis of the electron localization function (ELF) and Thom's catastrophe theory (CT) provides a powerful tool providing insight into molecular mechanisms of chemical rearrangements. In agreement with physical laws and quantum theoretical insights, BET can be considered as an appropriate tool to tackle chemical reactivity with a wide range of possible applications. Likewise, the present approach retrieves the classical curly arrows used to describe the rearrangements of chemical bonds for a given reaction mechanism, providing detailed physical grounds for this type of representation. The ideas underlying the valence-shell-electron pair-repulsion (VSEPR) model applied to non-equilibrium geometries provide simple chemical explanations of density transfers. For a given geometry around a central atom, the arrangement of the electronic domain may comply or not with the VSEPR rules according with the valence shell population of the considered atom. A deformation yields arrangements which are either VSEPR defective (at least a domain is missing to match the VSEPR arrangement corresponding to the geometry of the ligands), VSEPR compliant

  9. Computational assessment of pregnant woman models exposed to uniform ELF-magnetic fields: compliance with the European current exposure regulations for the general public and occupational exposures at 50 Hz

    International Nuclear Information System (INIS)

    Liorni, Ilaria; Parazzini, Marta; Fiocchi, Serena; Ravazzani, Paolo; Douglas, Mark; Capstick, Myles; Kuster, Niels

    2016-01-01

    The Recommendation 1999/529/EU and the Directive 2013/35/EU suggest limits for both general public and occupational exposures to extremely low-frequency magnetic fields, but without special limits for pregnant women. This study aimed to assess the compliance of pregnant women to the current regulations, when exposed to uniform MF at 50 Hz (100 μT for EU Recommendation and 1 and 6 mT for EU Directive). For general public, exposure of pregnant women and fetus always resulted in compliance with EU Recommendation. For occupational exposures, (1) Electric fields in pregnant women were in compliance with the Directive, with exposure variations due to fetal posture of 40 % in head tissues, (3) Electric fields in fetal CNS tissues of head are above the ICNIRP 2010 limits for general public at 1 mT (in 7 and 9 months gestational age) and at 6 mT (in all gestational ages). (authors)

  10. ELF whistler events with a reduced intensity observed by the DEMETER spacecraft

    Science.gov (United States)

    Zahlava, J.; Nemec, F.; Santolik, O.; Kolmasova, I.; Parrot, M.

    2017-12-01

    A survey of VLF frequency-time spectrograms obtained by the DEMETER spacecraft (2004-2010, altitude about 700 km) revealed that the intensity of fractional hop whistlers is sometimes significantly reduced at specific frequencies. These frequencies are typically above about 3.4 kHz (second cutoff frequency of the Earth-ionosphere waveguide), and they vary smoothly in time. The events were explained by the wave propagation in the Earth-ionosphere waveguide, and a resulting interference of the first few waveguide modes. We analyze the events whose frequency-time structure is rather similar, but at frequencies below 1 kHz. Altogether, 284 events are identified during the periods with active Burst mode, when high resolution data are measured by DEMETER. The vast majority of events (93%) occurs during the nighttime. All six electromagnetic field components are available, which allows us to perform a detailed wave analysis. An overview of the properties of these events is presented, and their possible origin is discussed.

  11. Survey of electromagnetic field exposure in bedrooms of residences in lower Austria.

    Science.gov (United States)

    Tomitsch, Johannes; Dechant, Engelbert; Frank, Wilhelm

    2010-04-01

    Previous investigations of exposure to electric, magnetic, or electromagnetic fields (EMF) in households were either about electricity supply EMFs or radio frequency EMFs (RF-EMFs). We report results from spot measurements at the bedside that comprise electrostatic fields, extremely low-frequency electric fields (ELF-EFs), extremely low-frequency magnetic fields (ELF-MFs), and RF-EMFs. Measurements were taken in 226 households throughout Lower Austria. In addition, effects of simple reduction measures (e.g., removal of clock radios or increasing their distance from the bed, turning off Digital Enhanced Cordless Telecommunication (DECT) telephone base stations) were assessed. All measurements were well below International Commission on Non-Ionizing Radiation Protection (ICNIRP) guideline levels. Average night-time ELF-MFs (long-term measurement from 10 pm to 6 am, geometric mean over households) above 100 nT were obtained in 2.3%, and RF-EMFs above 1000 microW/m(2) in 7.1% of households. Highest ELF-EFs were primarily due to lamps beside the bed (max = 166 V/m), and highest ELF-MFs because of transformers of devices (max = 1030 nT) or high current of power lines (max = 380 nT). The highest values of RF-EMFs were caused by DECT telephone base stations (max = 28979 microW/m(2)) and mobile phone base stations (max = 4872 microW/m(2)). Simple reduction measures resulted in an average decrease of 23 nT for ELF-MFs, 23 V/m for ELF-EFs, and 246 microW/m(2) for RF-EMFs. A small but statistically significant correlation between ELF-MF exposure and overall RF-EMF levels of R = 0.16 (P = 0.008) was computed that was independent of type (flat, single family) and location (urban, rural) of houses. (c) 2009 Wiley-Liss, Inc.

  12. Recent Intensified Winter Coldness in the Mid-High Latitudes of Eurasia and Its Relationship with Daily Extreme Low Temperature Variability

    Directory of Open Access Journals (Sweden)

    Chuhan Lu

    2016-01-01

    Full Text Available Observational records in recent decades show a large-scale decrease in the cold-season temperature variance in the Northern Hemisphere midlatitudes under continuous global warming. However, severe low temperature events in winter frequently occurred in midlatitude Eurasia (MEA in the last decade. Here, we define a new coldness intensity (CI index for the near-surface based on the amplitude of daily anomalously cold temperatures in winter to demonstrate the CI of the variability of low temperature extremes. The results show that a sign-consistent mode dominates the CI variation in MEA, with a marked intensification during the last decade via empirical orthogonal function (EOF analysis. This leading mode is significantly related to the frequency of winter extreme events. The associated circulations are characterized by a remarkable anomalous anticyclone in Northwest Eurasia, which induced substantial cold advection in MEA. The widespread intensified CI in MEA is closely linked with strong surface anticyclones and synoptic blocking in the mid-high latitudes (25°E–85°E. Coincidently, positive phase shifts of the first two leading modes of the extratropical circulation, which feature similar blocking-like anomalies in the northwestern Eurasian subarctic, jointly play an important role in the recent frequency of severe winters.

  13. ULF/ELF electromagnetic waves associated with the quasi-perpendicular earth's bow shock crossings

    International Nuclear Information System (INIS)

    Nozdrachev, M.N.; Petrukovich, A.A.

    1992-01-01

    The present paper is dedicated to the analysis of electromagnetic turbulence in the frequency range 0.1-75 Hz, associated with crossing of Earth's Bow Shock recorded by the Prognoz-8 and -10 satellites. The quasimonochromatic waves are identified in the shock transition region. Their frequencies, laying in the range from 2 Hz to 6 Hz upstream the shock ramp shift to the values less than 1 Hz in the downstream region. The amplitudes of these narrow emissions are high enough to provide the dissipation in the flow of the solar wind plasma. It is argued that spectra shapes in this frequency range 0.1-75 Hz are strongly affected by the Doppler shift

  14. Combined exposure of ELF magnetic fields and X-rays increased mutant yields compared with X-rays alone in pTN89 plasmids

    International Nuclear Information System (INIS)

    Koyama, Shin; Nakahara, Takehisa; Sakurai, Tomonori; Komatsubara, Yoshiki; Miyakoshi, Junji; Isozumi, Yasuhito

    2005-01-01

    We have examined mutations in the supF gene carried by pTN89 plasmids in Escherichia coli (E. coli) to examine the effects of extremely low frequency magnetic fields (ELFMFs) and/or X-rays to the plasmids. The plasmids were subjected to sham exposure or exposed to an ELFMF (5 mT), with or without X-ray irradiation (10 Gy). For the combined treatments, exposure to the ELFMF was immediately before or after X-ray irradiation. The mutant fractions were 0.94 x 10 -5 for X-rays alone, 1.58 x 10 -5 for an ELFMF followed by X-rays, and 3.64 x 10 -5 for X-rays followed by an ELFMF. Increased mutant fraction was not detected following exposure to a magnetic field alone, or after sham exposure. The mutant fraction for X-rays followed by an ELFMF was significantly higher than those of other treatments. Sequence analysis of the supF mutant plasmids revealed that base substitutions were dominant on exposure to X-rays alone and X-rays plus an ELFMF. Several types of deletions were detected in only the combined treatments, but not with X-rays alone. We could not find any mutant colonies in sham irradiated and an ELFMF alone treatment, but exposure to ELFMFs immediately before or after X-ray irradiation may enhance the mutations. Our results indicate that an ELFMF increases mutation and alters the spectrum of mutations. (author)

  15. Sickness absence from 1978 to 1992 of Electricite de France (EDF) workers exposed to ELF-EMF: the substation group

    International Nuclear Information System (INIS)

    Souques, M.; Dab, W.; Lambrozo, J.; Chevalier, A.; Coing, F.

    1996-01-01

    Electromagnetic fields are suspected of many health effects, including cancers, immunity and fertility disorders, congenital malformations, suicides and depression.... Although the results of all studies are contradictory and no biological mechanism has been found, populations are concerned about this matter. This study analyzes the absence from work of some EDF employees who are a priori the most professionally exposed to ELF EMF. Absence from work is taken as an health indicator. Although it is not specific, it can be predictive of serious health problems. The specific context of EDF has made it possible to collect and analyze the medical aspect of absence from work, that is rare in France. We were interested with employees working with high voltage (over 90 kV). Three job categories have been selected: live line workers, substation maintenance workers and substation exploitation workers (called in the company the ATEX). The first group concerned the live linemen and the results were exposed previously. It appeared they had more accidents at work, but this was more related to the job of lineman rather than to the EMF exposure. Nevertheless, substation workers have an exposure less intensive but longer than live linemen. We present here the result about the absenteeism of the substation workers, maintenance and exploitation. (author)

  16. Mathematical modeling and measurement of electric fields of electrode-based through-the-earth (TTE) communication

    OpenAIRE

    Yan, Lincan; Zhou, Chenming; Reyes, Miguel; Whisner, Bruce; Damiano, Nicholas

    2017-01-01

    There are two types of through-the-earth (TTE) wireless communication in the mining industry: magnetic loop TTE and electrode-based (or linear) TTE. While the magnetic loop systems send signal through magnetic fields, the transmitter of an electrode-based TTE system sends signal directly through the mine overburden by driving an extremely low frequency (ELF) or ultralow frequency (ULF) AC current into the earth. The receiver at the other end (underground or surface) detects the resultant curr...