Einloggen

Thematische Bibliographien / Radiofrequency measurements / Zeitschriftenartikel

Um die anderen Arten von Veröffentlichungen zu diesem Thema anzuzeigen, folgen Sie diesem Link: Radiofrequency measurements.

Zeitschriftenartikel zum Thema „Radiofrequency measurements“

Autor: Grafiati

Veröffentlicht am 22. Februar 2025

Geben Sie eine Quelle nach APA, MLA, Chicago, Harvard und anderen Zitierweisen an

Wählen Sie eine Art der Quelle aus:

Machen Sie sich mit Top-50 Zeitschriftenartikel für die Forschung zum Thema "Radiofrequency measurements" bekannt.

Neben jedem Werk im Literaturverzeichnis ist die Option "Zur Bibliographie hinzufügen" verfügbar. Nutzen Sie sie, wird Ihre bibliographische Angabe des gewählten Werkes nach der nötigen Zitierweise (APA, MLA, Harvard, Chicago, Vancouver usw.) automatisch gestaltet.

Sie können auch den vollen Text der wissenschaftlichen Publikation im PDF-Format herunterladen und eine Online-Annotation der Arbeit lesen, wenn die relevanten Parameter in den Metadaten verfügbar sind.

Sehen Sie die Zeitschriftenartikel für verschiedene Spezialgebieten durch und erstellen Sie Ihre Bibliographie auf korrekte Weise.

1

Vulevic, Branislav, Cedomir Belic und Luka Perazic. „Measurement uncertainty in broadband radiofrequency radiation level measurements“. Nuclear Technology and Radiation Protection 29, Nr. 1 (2014): 53–57. http://dx.doi.org/10.2298/ntrp1401053v.

Der volle Inhalt der Quelle

Annotation:

For the evaluation of measurement uncertainty in the measurement of broadband radio frequency radiation, in this paper we propose a new approach based on the experience of the authors of the paper with measurements of radiofrequency electric field levels conducted in residential areas of Belgrade and over 35 municipalities in Serbia. The main objective of the paper is to present practical solutions in the evaluation of broadband measurement uncertainty for the in-situ RF radiation levels.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

2

Sergiyenko, P. Yu, K. H. Savyn und Yu V. Prokopenko. „Low power and high speed testing operating modes of Bluetooth devices“. Electronics and Communications 15, Nr. 4 (29.03.2010): 188–91. https://doi.org/10.20535/2312-1807.2010.15.4.301768.

Der volle Inhalt der Quelle

Annotation:

The aim of this work is discussing about peculiarities of radiofrequency characteristics measurement for Low Energy and High Speed Bluetooth devices. Measurement technique was implemented in the TC-3000C tester platform. Some practical measurements have been performed. A number of characteristics which give the opportunity to determine main radiofrequency parameters have been achieved

APA, Harvard, Vancouver, ISO und andere Zitierweisen

3

Tyrakis, Ch, V. Softa, A. Alexias, Y. Kiouvrekis, K. Theodorou und C. Kappas. „Radiofrequency exposure measurements in Greece“. Physica Medica 92 (Dezember 2021): S249—S250. http://dx.doi.org/10.1016/s1120-1797(22)00540-3.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

4

Allen, S. G. „Radiofrequency field measurements and hazard assessment“. Journal of Radiological Protection 11, Nr. 1 (März 1991): 49–62. http://dx.doi.org/10.1088/0952-4746/11/1/005.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

5

Antonsson, Johan, Ola Eriksson, Peter Lundberg und Karin Wårdell. „Optical Measurements during Experimental Stereotactic Radiofrequency Lesioning“. Stereotactic and Functional Neurosurgery 84, Nr. 2-3 (2006): 118–24. http://dx.doi.org/10.1159/000094463.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

6

Stuchly, M. A., J. A. Kozlowski, S. Symons und D. W. Lecuyer. „Measurements of Contact Currents in Radiofrequency Fields“. Health Physics 60, Nr. 4 (April 1991): 547–57. http://dx.doi.org/10.1097/00004032-199104000-00009.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

7

Chang, Chieh-feng, Hsuan-Yu Kuo und Jo-Ping Lee. „AC measurements and simulations of hepatic radiofrequency ablation“. International Journal of Hyperthermia 38, Nr. 1 (01.01.2021): 1322–32. http://dx.doi.org/10.1080/02656736.2021.1971779.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

8

Canet, D., B. Diter, A. Belmajdoub, J. Brondeau, J. C. Boubel und K. Elbayed. „Self-diffusion measurements using a radiofrequency field gradient“. Journal of Magnetic Resonance (1969) 81, Nr. 1 (Januar 1989): 1–12. http://dx.doi.org/10.1016/0022-2364(89)90263-1.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

9

Stuchly, Stanislaw S., Andrzej Kraszewski und Maria A. Stuchly. „Uncertainties in radiofrequency dielectric measurements of biological substances“. IEEE Transactions on Instrumentation and Measurement IM-36, Nr. 1 (März 1987): 67–70. http://dx.doi.org/10.1109/tim.1987.6312632.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

10

Stefu, N., I. Solyom und A. Arama. „Radiofrequency Electromagnetic Field Map of Timisoara“. Annals of West University of Timisoara - Physics 58, Nr. 1 (01.12.2015): 73–80. http://dx.doi.org/10.1515/awutp-2015-0209.

Der volle Inhalt der Quelle

Annotation:

Abstract There are many electromagnetic field (EMF) sources nowadays acting simultaneously, especially in urban areas, making the theoretical estimation of electromagnetic power at ground level very difficult. This paper reports on EMF maps built with measurements collected in Timisoara, at various radiofrequencies. A grid of 15×15 squares was built (approximate resolution 400m x 400m) and measurements of the average and maximum values of the electric field E, magnetic field H and total power density S at 0.9, 1.8 and 2.4 GHz were collected in every node of the grid. Positions of the nodes in terms of latitude and longitude were also collected. Maps were built presenting the spatial distribution of the measured quantities over Timisoara. Potential influences of EMF on public health are discussed.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

11

Aboelmagd, Shreen R., Mahmoud A. Elsayed, Mai Helmy Hassan, Afaf M. Botla, Hazem S. El Ashmawi und Reham E. Hamoda. „Effect of radiofrequency on postmenopausal adipose tissue: A randomized control trial“. Fizjoterapia Polska 24, Nr. 1 (21.03.2024): 91–97. http://dx.doi.org/10.56984/8zg2ef83b3.

Der volle Inhalt der Quelle

Annotation:

Aim. To determine the effect of radiofrequency on anthropometric measurements and lipid profile in postmenopausal women. Material and methods. Sixty postmenopausal women diagnosed as having abdominal adiposity and abnormal lipid profiles were incorporated into this study. Participants were assigned at random into two equal groups. Group A adhered to a Mediterranean diet and engaged in aerobic exercise for 12 weeks (n = 30), whereas group B followed a Mediterranean diet and participated in both aerobic exercise and radiofrequency treatments for the same 12-week period (n = 30). Both groups had their anthropometric measurements, encompassing weight, body mass index (BMI), and waist circumference, along with lipid profile components involving total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), very-low-density lipoprotein (VLDL), and triglycerides (TG), assessed before and after the 12-week program duration. Results. Significant improvements (p < 0.05) were noted in all outcome measures within both groups. Upon post-treatment comparison, both groups exhibited statistically significant reductions in all anthropometric measurements, LDL and TG (p < 0.05), while there was a statistically significant increase in HDL (p < 0.05) favoring group B. Nevertheless, there were no significant differences between groups for TC and VLDL (p > 0.05) after treatment. Conclusion. Radiofrequency has positive effect on anthropometric measurements and lipid profile in postmenopausal women.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

12

Fakri-Bouchet, L., Ch Lapray und A. Briguet. „Measurements of the radiofrequency field in magnetic resonance coils“. Measurement Science and Technology 9, Nr. 9 (01.09.1998): 1641–46. http://dx.doi.org/10.1088/0957-0233/9/9/040.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

13

Roser, Katharina, Anna Schoeni, Benjamin Struchen, Marco Zahner, Marloes Eeftens, Jürg Fröhlich und Martin Röösli. „Personal radiofrequency electromagnetic field exposure measurements in Swiss adolescents“. Environment International 99 (Februar 2017): 303–14. http://dx.doi.org/10.1016/j.envint.2016.12.008.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

14

Graedel, Nadine N., Jonathan R. Polimeni, Bastien Guerin, Borjan Gagoski und Lawrence L. Wald. „An anatomically realistic temperature phantom for radiofrequency heating measurements“. Magnetic Resonance in Medicine 73, Nr. 1 (18.02.2014): 442–50. http://dx.doi.org/10.1002/mrm.25123.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

15

Crha, Michal, Jan Hlavsa, Vladimír Procházka, Tomáš Andrašina, Iva Svobodová, Lucie Urbanová, Tomáš Pavlík et al. „Radiofrequency ablation of pancreas and optimal cooling of peripancreatic tissue in an ex-vivo porcine model“. Acta Veterinaria Brno 80, Nr. 4 (2011): 407–13. http://dx.doi.org/10.2754/avb201180040407.

Der volle Inhalt der Quelle

Annotation:

Radiofrequency ablation is a possible palliative treatment for patients suffering from pancreatic neoplasia. However, radiofrequency-induced damage to the peripancreatic tissues during pancreatic ablation might cause fatal complications. The aim of this experimental ex vivo study on pigs was to verify ablation protocols and evaluate whether or not the cooling of peripancereatic tissues during pancreatic ablation has any benefit for their protection against thermal injury. Radiofrequency ablation was performed on 52 pancreatic specimens obtained from pigs. During each pancreatic ablation, continuous measurements of the temperature in the portal vein and duodenal lumen were performed. Peripancreatic tissues were either not cooled or were cooled by being submerged in 14 °C water, or by a perfusion of the portal vein and duodenum with 14 °C saline. The effects of variation in target temperature of the ablated area (90 °C and 100 °C), duration of ablation (5 and 10 min) and the effect of peripancreatic tissues cooling were studied. We proved that optimal radiofrequency ablation of the porcine pancreas can be reached with the temperature of 90 °C for 5 min in the ablated area. The perfusion of the duodenal and portal vein by 14 °C saline was found to be the most effective cooling method for minimizing damage to the walls. Continuous measurement of temperatures in peripancreatic tissues will provide useful feedback to assist in their protection against thermal injury. This therapy could be used in the treatment of pancreatic tumours.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

16

Le Breton, Mathieu, Éric Larose, Laurent Baillet, Yves Lejeune und Alec van Herwijnen. „Monitoring snow water equivalent using the phase of RFID signals“. Cryosphere 17, Nr. 8 (04.08.2023): 3137–56. http://dx.doi.org/10.5194/tc-17-3137-2023.

Der volle Inhalt der Quelle

Annotation:

Abstract. The amount of water contained in a snowpack, known as snow water equivalent (SWE), is used to anticipate the amount of snowmelt that could supply hydroelectric power plants, fill water reservoirs, or sometimes cause flooding. This work introduces a wireless, non-destructive method for monitoring the SWE of a dry snowpack. The system is based on an array of low-cost passive radiofrequency identification (RFID) tags, placed under the snow and read at 865–868 MHz by a reader located above the snow. The SWE was deduced from the phase delay of the tag's backscattered response, which increases with the amount of snow traversed by the radiofrequency wave. Measurements taken in the laboratory, during snowfall events and over 4.5 months at the Col de Porte test field, were consistent with reference measurements of cosmic rays, precipitation and snow pits. SWE accuracy was ±18 kg m−2 throughout the season (averaged over three tags) and ±3 kg m−2 during dry snowfall events (averaged over data from two antennas and four or five tags). The overall uncertainty compared to snow weighing was ±10 % for snow density in the range 61–390 kg m−3. The main limitations observed were measurement bias caused by wet snow (biased data were discarded) and the need for phase unwrapping. The method has a number of advantages: it allows for continuous measurement (1 min sampling rate in dry snow), it can provide complementary measurement of tag temperature, it does not require the reception of external data, and it opens the way towards spatialized measurements. The results presented also demonstrate that RFID propagation-based sensing can remotely monitor the permittivity of a low-loss dielectric material with scientific-level accuracy.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

17

Sokolov, Sergey, Arthur Novikov und Marianna Polyakova. „Adaptive Stochastic Filtration Based on the Estimation of the Covariance Matrix of Measurement Noises Using Irregular Accurate Observations“. Inventions 6, Nr. 1 (21.01.2021): 10. http://dx.doi.org/10.3390/inventions6010010.

Der volle Inhalt der Quelle

Annotation:

In measurement systems operating under various disturbances the probabilistic characteristics of measurement noises are usually known approximately. To improve the observation accuracy, a new approach to the Kalman’s filter adaptation is proposed. In this approach, the Covariance Matrix of Measurement Noises (CMMN) is estimated by accurate measurements detected irregularly by the mobile object observation system (from radiofrequency identifiers, etalon reference, fixed points etc.). The problem of adaptive estimation of the observer’s noises covariance matrix in the Kalman filter is solved analytically for two cases: mutual noises correlation, and its absence. The numerical example for adaptive filtration of complexing navigation system parameters of a mobile object using irregular accurate measurements is given to illustrate the effectiveness of the proposed algorithm. Coordinate estimating errors have changed in comparison with the traditional scheme from 100 m to 2 m in latitude, and from 200 m to 1.5 m in longitude.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

18

Oluwafemi, Ilesanmi Banjo, und Olusegun Johnson Adeoye. „Mobile Phone Radiofrequency Radiation Assessment Based on Call-Related Factors and Physical Condition from Selected Mobile Phones“. European Journal of Engineering Research and Science 5, Nr. 3 (20.03.2020): 343–47. http://dx.doi.org/10.24018/ejers.2020.5.3.1799.

Der volle Inhalt der Quelle

Annotation:

The intensity of electromagnetic radiation around selected mobile phones is in a bid to confirm their adherence to the specified radiofrequency exposure limit on non-ionizing radiation. Measurements were taken with the use of Radiofrequency Meter (RF) TM-96, 9V DC and Spectrum Analyzer (NA-773, 144/430 MHz) at distances 5 cm, 10 cm, 15 cm, 20 cm, 25 cm and 30 cm from the mobile phone users. The level of radiations from the selected mobile phones ranges from 0.3119 to 0.5407 mW/cm2 during dialing. Out of the tested mobile phones, the radiation levels of Asus, Infinix 3 and Siccoo X100 phones which are 0.5407, 0.5009 and 0.4506 mW/cm2 respectively are above the International Commission on Non-ionizing Radiation Protection (ICNIRP) reference level which is 0.45 mW/cm2. Result from measurement showed that high radiation levels from a transmitting handset occur between seeking for connection and call establishment. It was also confirmed that the physical condition of mobile phones affects its radiation level.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

19

Oluwafemi, Ilesanmi Banjo, und Olusegun Johnson Adeoye. „Mobile Phone Radiofrequency Radiation Assessment Based on Call-Related Factors and Physical Condition from Selected Mobile Phones“. European Journal of Engineering and Technology Research 5, Nr. 3 (20.03.2020): 343–47. http://dx.doi.org/10.24018/ejeng.2020.5.3.1799.

Der volle Inhalt der Quelle

Annotation:

The intensity of electromagnetic radiation around selected mobile phones is in a bid to confirm their adherence to the specified radiofrequency exposure limit on non-ionizing radiation. Measurements were taken with the use of Radiofrequency Meter (RF) TM-96, 9V DC and Spectrum Analyzer (NA-773, 144/430 MHz) at distances 5 cm, 10 cm, 15 cm, 20 cm, 25 cm and 30 cm from the mobile phone users. The level of radiations from the selected mobile phones ranges from 0.3119 to 0.5407 mW/cm2 during dialing. Out of the tested mobile phones, the radiation levels of Asus, Infinix 3 and Siccoo X100 phones which are 0.5407, 0.5009 and 0.4506 mW/cm2 respectively are above the International Commission on Non-ionizing Radiation Protection (ICNIRP) reference level which is 0.45 mW/cm2. Result from measurement showed that high radiation levels from a transmitting handset occur between seeking for connection and call establishment. It was also confirmed that the physical condition of mobile phones affects its radiation level.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

20

Overzet, L. J., und F. Y. Leong-Rousey. „Time-resolved power and impedance measurements of pulsed radiofrequency discharges“. Plasma Sources Science and Technology 4, Nr. 3 (01.08.1995): 432–43. http://dx.doi.org/10.1088/0963-0252/4/3/013.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

21

Pant, V., R. G. Goodrich, M. G. Godbole und D. H. Lowndes. „Radiofrequency impedance measurements at 2 MHz on YBa2Cu3O7 epitaxial films“. Philosophical Magazine B 80, Nr. 11 (November 2000): 1961–74. http://dx.doi.org/10.1080/13642810008216519.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

22

HARTUNG, WOLFGANG M., M. ERICK BURTON, A. GREGORY DEAM, PAUL F. WALTER, KEVIN McTEAGUE und JONATHAN J. LANGBERG. „Estimation of Temperature During Radiofrequency Catheter Ablation Using Impedance Measurements“. Pacing and Clinical Electrophysiology 18, Nr. 11 (November 1995): 2017–21. http://dx.doi.org/10.1111/j.1540-8159.1995.tb03862.x.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

23

Humbert, F., M. Valtier, A. Retournard und D. Canet. „Diffusion Measurements Using Radiofrequency Field Gradient: Artifacts, Remedies, Practical Hints“. Journal of Magnetic Resonance 134, Nr. 2 (Oktober 1998): 245–54. http://dx.doi.org/10.1006/jmre.1998.1541.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

24

Röösli, Martin, Patrizia Frei, Evelyn Mohler, Charlotte Braun-Fahrländer, Alfred Bürgi, Jürg Fröhlich, Georg Neubauer, Gaston Theis und Matthias Egger. „Statistical analysis of personal radiofrequency electromagnetic field measurements with nondetects“. Bioelectromagnetics 29, Nr. 6 (September 2008): 471–78. http://dx.doi.org/10.1002/bem.20417.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

25

Zimmermann, Corinna, Adrian Michelmann, Yannick Daniel, Markus D. Enderle, Nermin Salkic und Walter Linzenbold. „Application of Deep Learning for Real-Time Ablation Zone Measurement in Ultrasound Imaging“. Cancers 16, Nr. 9 (27.04.2024): 1700. http://dx.doi.org/10.3390/cancers16091700.

Der volle Inhalt der Quelle

Annotation:

Background: The accurate delineation of ablation zones (AZs) is crucial for assessing radiofrequency ablation (RFA) therapy’s efficacy. Manual measurement, the current standard, is subject to variability and potential inaccuracies. Aim: This study aims to assess the effectiveness of Artificial Intelligence (AI) in automating AZ measurements in ultrasound images and compare its accuracy with manual measurements in ultrasound images. Methods: An in vitro study was conducted using chicken breast and liver samples subjected to bipolar RFA. Ultrasound images were captured every 15 s, with the AI model Mask2Former trained for AZ segmentation. The measurements were compared across all methods, focusing on short-axis (SA) metrics. Results: We performed 308 RFA procedures, generating 7275 ultrasound images across liver and chicken breast tissues. Manual and AI measurement comparisons for ablation zone diameters revealed no significant differences, with correlation coefficients exceeding 0.96 in both tissues (p < 0.001). Bland–Altman plots and a Deming regression analysis demonstrated a very close alignment between AI predictions and manual measurements, with the average difference between the two methods being −0.259 and −0.243 mm, for bovine liver and chicken breast tissue, respectively. Conclusion: The study validates the Mask2Former model as a promising tool for automating AZ measurement in RFA research, offering a significant step towards reducing manual measurement variability.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

26

Mirarchi, Luciano, Valentina Giaquinto, Sergio Silvestri und Rita Massa. „A Standard Protocol Proposal for Reliable and Time-Saving Shielding Effectiveness Measurements for MRI Faraday Cages“. Open Biomedical Engineering Journal 14, Nr. 1 (20.03.2020): 1–10. http://dx.doi.org/10.2174/1874120702014010001.

Der volle Inhalt der Quelle

Annotation:

Background: An inadequate shielding of radio-frequency cabins for magnetic resonance imaging devices can affect clinical images with artifacts. For this reason, periodic measurements of shielding effectiveness are recommended. However, a wide gap exists between the international reference standard currently available for shielding effectiveness measurement (IEEE-Std 299/2006) and the practical approach, mainly because of the poor applicability of the standard to any situation. Objective: The aim of this work is to suggest a novel procedure for the measurement of the shielding effectiveness of radiofrequency cabins for clinical magnetic resonance imaging devices. The application of the cabin door measurements for shielding effectiveness assessment is proposed. Methods: Based on the only international standard currently available, some critical aspects of shielding effectiveness measurements are highlighted. Taking into account theoretical considerations, a novel approach is suggested in order to simplify the applicability of the standard. Frequency ranges and measurement points were reduced by considering the specific device inside the shield. Results: Results obtained by the application of the proposed protocol were compared with the results obtained by the application of the standard procedure IEEE-Std 299/2006. No significant discrepancies between measurements have been found. It was observed that the time to perform measurements reduced by almost three times. Conclusion: A time-saving method for measurement of shielding effectiveness in a narrow range of frequencies is proposed.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

27

Abbassi, A., M. Saint-Paul, R. Dkiouak, M. R. Britel, Z. S. Wang, H. Luo, X. Lu, C. Ren und H. H. Wen. „Surface impedance of BaFe2-xNixAs2 in the radio frequency range“. Advanced Electromagnetics 1, Nr. 2 (25.08.2012): 1. http://dx.doi.org/10.7716/aem.v1i2.61.

Der volle Inhalt der Quelle

Annotation:

We report measurements of the temperature dependence of the surface impedance in superconducting BaFe1.93Ni0.07As2 crystals using the radiofrequency reflection technique in the 5<T<30K temperature range. An LC resonant circuit with a phase sensitive detection was used at 92MHz. A measurement assembly with point contacts was used at 30MHz. The recent discovery of iron based arsenide superconductors BaFe2-xNixAs2 has attracted much interest. For a Ni doping level of 7% the superconducting phase transition is found around 20K. The temperature dependence of the superconducting penetration depth was determined.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

28

Kisser, U., K. Stelter, R. Gurkov, M. Patscheider, F. Schrotzlmair, R. Bytyci, C. Adderson-Kisser, A. Berghaus und B. Olzowy. „Diode laser versus radiofrequency treatment of the inferior turbinate - a randomized clinical trial“. Rhinology journal 52, Nr. 4 (01.12.2014): 424–30. http://dx.doi.org/10.4193/rhino14.001.

Der volle Inhalt der Quelle

Annotation:

Background: Laser and radiofrequency induced volume reduction of the inferior turbinates are frequently used treatment modalities. Which of both is superior, however, is not clear to date due to a lack of controlled prospective studies. Here, we compare both methods regarding improvement of nasal breathing, complications, patient comfort and wound healing. Methodology: Prospective, randomized, single-blinded clinical trial with intra-individual design. After randomization, one side of the nose was treated with a 940nm diode laser and the other side with bipolar radiofrequency therapy. Pre- and postoperative evaluation was performed using visual analogue scales, nasal endoscopy and objective measurements of nasal patency. Results: Of 27 enrolled patients, 26 completed the protocol. No severe complications were observed. Intraoperative discomfort was significantly more severe on the radiofrequency side. After three months, a significant reduction of nasal obstruction was observed for laser treatment and radiofrequency therapy with no significant difference between them. Objective parameters did not improve significantly. When asked which treatment modality they would chose again 50 % of the patients decided for radiofrequency treatment, 23 % for laser treatment, and 19 % for both. Conclusion: DLVR and RFVR are well-tolerated treatment modalities and both significantly reduce the degree of nasal obstruction in patients with hypertrophic inferior turbinates. There was no significant difference between both treatment modalities regarding efficiency.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

29

Karatas, A., M. Salviz, B. Dikmen, T. Yuce und G. Acar. „The effects of different radiofrequency energy magnitudes on mucociliary clearance in cases of turbinate hypertrophy“. Rhinology journal 53, Nr. 2 (01.06.2015): 171–75. http://dx.doi.org/10.4193/rhino14.208.

Der volle Inhalt der Quelle

Annotation:

Background: Radiofrequency ablation (RFA) application is a commonly used technique for the treatment of inferior turbinate hypertrophies. As the number of RFA applications has increased, some problems have been reported regarding the patient discomfort. The most frequent problems among these are the extended turbinate crusting and nasal obstruction. Methods: Patients who received RFA were divided into two groups based on the applied energy value during the employment of the technique. Each group was including 30 patients. The patients in the first group received 8 watts and those in the second received 12 watts of energy. Saccharin transport times (STT) were measured four times. First a baseline measurement was performed followed by measurements on the 15th, 30th, and 45th days after the initial procedure. Nasal obstruction was twice assessed by peak nasal inspiratory flow (PNIF) measurements, which were taken both before the procedure and on the 45th day after the procedure. Turbinate surface crustings that were observed for more than 15 days were considered as an extended turbinate crusting. Results: The STT and PNIF measurements taken before the procedure were not significantly different between the two groups. Postprocedure STT measurements were significantly higher than the preprocedure measurements taken in both groups, and were stable within the physiological range. The STT increase in Group II was significantly greater than in Group I. Postprocedure PNIF values in both groups were significantly higher than the preprocedure values. Group II had showed a significantly higher rate of crusting. Conclusion: Higher magnitudes of energy elongate the healing process of the turbinate tissue and they affect more extensively the mucociliary clearance. Elongation of the healing process of the turbinate tissue may increase the rate of postprocedural complications such as turbinate surface crusting.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

30

Пашнев, В. К., Э. Л. Сороковой, А. А. Петрушеня und Ф. И. Ожерельев. „Влияние низкочастотных флуктуаций магнитного поля на удержание плазмы в торсатроне Ураган-3М при редких частотах столкновений“. Журнал технической физики 89, Nr. 1 (2019): 55. http://dx.doi.org/10.21883/jtf.2019.01.46962.103-18.

Der volle Inhalt der Quelle

Annotation:

AbstractThe plasma energy content in the Uragan-3M torsatron was determined by means of diamagnetic measurements under the conditions of its radiofrequency (RF) generation and heating (at near ion-cyclotron frequencies) in the presence of bootstrap current. The balance of power under the fast heating of plasma was considered and used as a basis to estimate the radiofrequency power absorbed by the plasma in the confinement volume. The behavior of energy losses in the discharge period was calculated, and the effect of magnetic field fluctuations on the energy losses within a frequency range of 0.5–70 kHz was discussed.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

31

Rathebe, Phoka C. „Exposure levels of radiofrequency electromagnetic fields from mobile base stations in Mpumalanga province, South Africa“. Journal of Physics: Conference Series 2591, Nr. 1 (01.09.2023): 012035. http://dx.doi.org/10.1088/1742-6596/2591/1/012035.

Der volle Inhalt der Quelle

Annotation:

Abstract This study assessed the radiofrequency electromagnetic fields (RF-EMF) exposure levels proximal to primary school structures in the Mpumalanga province of South Africa. A calibrated Acoustimeter was used to measure the RF EMF levels at defined distance points of 50 and 100m away from the three mobile base stations, that provide a 4G network coverage. All the measurements were obtained from three mobile stations, each from one district municipality, using 30 minutes intervals for repeated measurements. The measured peak exposure level at 50m was 887 μW/m2 and 905 μW/m2 at 100m. No statistical difference was found when comparing the measurement data obtained at 50 and 100m from the three district municipalities. However, comparison of measurements obtained at 50 and 100m for all base stations were statistically significant, p-value< .002 and p< .003 respectively. The measured RF EMF exposure levels at both distance points were below the reference levels found under International Commission for Non-ionizing Radiation Protection (ICNIRP) RF guidelines. It is therefore essential for mobile base station companies to consider proximity of residential structures when installing new base stations in the future, and regularly maintain the components of mobile base towers, especially in the current state of power load shedding in South Africa.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

32

Vogt, Klaus, Inese Daine-Loza und Maris Sperga. „Comparison of the thermal effects of Coblation and Radiofrequency waves in a porcine turbinate model“. Romanian Journal of Rhinology 8, Nr. 31 (01.09.2018): 157–64. http://dx.doi.org/10.2478/rjr-2018-0017.

Der volle Inhalt der Quelle

Annotation:

Abstract BACKGROUND. Radiofrequency reduction and Coblation are widely used procedures for the treatment of functionally enlarged turbinates with an appropriate outcome. Bleeding and crusting are postoperative complications for Coblation. Thermographic measurements and histological analyses were used to elucidate the causes. MATERIAL AND METHODS. In a porcine turbinate model, double-needle electrodes of different lengths were tested using a 4MHz radiofrequency current with either automatic energy limitation or a predetermined energy amount of 200 J. Coblation, according to the manufacturer’s instructions, was carried out with a Reflex Ultra 45 wand. The generated temperature was measured with thermo-probes at the tip of the electrodes. The mucosa was subsequently investigated histologically. RESULTS. Without preoperative saline injection, all procedures generate temperatures < 100° C. After saline injection, excessive temperatures are reached by Coblation after the release of plasma in a closed system. The follow-up is a severe deterioration of the microscopic structures of the mucosa. The low-temperature advantages of Coblation are only effective if the mandatory saline solution rinses the surface. The Radiofrequency applications deliver more predictable results. CONCLUSION. For the treatment of the functional enlargement of the turbinates, Radiofrequency current with proofed settings should be chosen.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

33

Fu, Yan, Laurent Dussopt, Tan Phu Vuong und Fabien Ndagijimana. „Characterization of integrated antennas at millimeter-wave frequencies“. International Journal of Microwave and Wireless Technologies 4, Nr. 1 (14.10.2011): 15–22. http://dx.doi.org/10.1017/s1759078711000912.

Der volle Inhalt der Quelle

Annotation:

This paper presents two feeding techniques for the radiation characterization of integrated antennas at millimeter-wave frequencies. The first method involves feeding the antenna-under-test (AUT) with a radiofrequency (RF) probe. We compare the measurements obtained with a standard RF probe, an extended probe, and an extended probe with reversed connector orientation. We find that the reversed orientation probe produces the best results in terms of effective measurement angular sector and reduction of ripples due to diffraction. The second method involves feeding the AUT through a flexible transmission line. This method achieves a larger range of measurement angles, but still suffers from parasitic scattering likely due to the mounting bracket and still need further development.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

34

Ramirez-Vazquez, Raquel, Sameer Arabasi, Hussein Al-Taani, Suhad Sbeih, Jesus Gonzalez-Rubio, Isabel Escobar und Enrique Arribas. „Georeferencing of Personal Exposure to Radiofrequency Electromagnetic Fields from Wi-Fi in a University Area“. International Journal of Environmental Research and Public Health 17, Nr. 6 (14.03.2020): 1898. http://dx.doi.org/10.3390/ijerph17061898.

Der volle Inhalt der Quelle

Annotation:

In the last two decades, due to the development of the information society, the massive increase in the use of information technologies, including the connection and communication of multiple electronic devices, highlighting Wi-Fi networks, as well as the emerging technological advances of 4G and 5G (new-generation mobile phones that will use 5G), have caused a significant increase in the personal exposure to Radiofrequency Electromagnetic Fields (RF-EMF), and as a consequence, increasing discussions about the possible adverse health effects. The main objective of this study was to measure the personal exposure to radiofrequency electromagnetic fields from the Wi-Fi in the university area of German Jordanian University (GJU) and prepare georeferenced maps of the registered intensity levels and to compare them with the basic international restrictions. Spot measurements were made outside the university area at German Jordanian University. Measurements were made in the whole university area and around two buildings. Two Satimo EME SPY 140 (Brest, France) personal exposimeters were used, and the measurements were performed in the morning and afternoon, and on weekends and weekdays. The total average personal exposure to RF-EMF from the Wi-Fi band registered in the three study areas and in the four days measured was 28.82 μW/m2. The average total exposure from the Wi-Fi band registered in the ten measured points of the university area of GJU was 22.97 μW/m2, the one registered in the eight measured points of building H was 34.48 μW/m2, and the one registered in the eight points of building C was 29.00 μW/m2. The maximum average values registered in the campus of GJU are below the guidelines allowed by International Commission on Non-ionizing Radiation Protection (ICNIRP). The measurement protocol used in this work has been applied in measurements already carried out in Spain and Mexico, and it is applicable in university areas of other countries.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

35

Melzer, A., R. Flohr und A. Piel. „Comparison of probe measurements and emission spectroscopy in a radiofrequency discharge“. Plasma Sources Science and Technology 4, Nr. 3 (01.08.1995): 424–31. http://dx.doi.org/10.1088/0963-0252/4/3/012.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

36

Xiao, B. P., X. Zhao, J. Spradlin, C. E. Reece, M. J. Kelley, T. Tan und X. X. Xi. „Surface impedance measurements of single crystal MgB2films for radiofrequency superconductivity applications“. Superconductor Science and Technology 25, Nr. 9 (02.07.2012): 095006. http://dx.doi.org/10.1088/0953-2048/25/9/095006.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

37

Hegman, N., S. Meszaros und K. Vad. „Apparatus for complex AC magnetic susceptibility measurements in the radiofrequency range“. Measurement Science and Technology 6, Nr. 1 (01.01.1995): 33–40. http://dx.doi.org/10.1088/0957-0233/6/1/007.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

38

Sovlukov, A. S., und V. I. Tereshin. „Radiofrequency temperature-independent measurements of the density of liquefied hydrocarbon gases“. Measurement Techniques 51, Nr. 7 (Juli 2008): 791–93. http://dx.doi.org/10.1007/s11018-008-9116-z.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

39

Peterson, D. J., K. Ford, J. Brandon, S. C. Shannon, T. Koh, T. C. Chua, K. Bera, W. Tian, S. Rauf und P. A. Kraus. „Radiofrequency phase resolved electron density measurements with the hairpin resonator probe“. Journal of Physics D: Applied Physics 53, Nr. 14 (23.01.2020): 145203. http://dx.doi.org/10.1088/1361-6463/ab6944.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

40

STAGEGAARD, N., H. PETERSEN, X. CHEN und J. SVENDSEN. „Indication of the radiofrequency induced lesion size by pre-ablation measurements“. Europace 7, Nr. 6 (November 2005): 525–34. http://dx.doi.org/10.1016/j.eupc.2005.05.016.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

41

Malveau, C., B. Diter, F. Humbert und D. Canet. „Self-Diffusion Measurements by Carbon-13 NMR Using Radiofrequency Field Gradients“. Journal of Magnetic Resonance 130, Nr. 1 (Januar 1998): 131–34. http://dx.doi.org/10.1006/jmre.1997.1280.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

42

Bolte, John F. B., Gerard van der Zande und Jos Kamer. „Calibration and uncertainties in personal exposure measurements of radiofrequency electromagnetic fields“. Bioelectromagnetics 32, Nr. 8 (04.05.2011): 652–63. http://dx.doi.org/10.1002/bem.20677.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

43

Gryz, Krzysztof, Patryk Zradziński und Jolanta Karpowicz. „The Role of the Location of Personal Exposimeters on the Human Body in Their Use for Assessing Exposure to the Electromagnetic Field in the Radiofrequency Range 98–2450 MHz and Compliance Analysis: Evaluation by Virtual Measurements“. BioMed Research International 2015 (2015): 1–12. http://dx.doi.org/10.1155/2015/272460.

Der volle Inhalt der Quelle

Annotation:

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

APA, Harvard, Vancouver, ISO und andere Zitierweisen

44

Onishi, Teruo, Kaoru Esaki, Kazuhiro Tobita, Miwa Ikuyo, Masao Taki und Soichi Watanabe. „Large-Area Monitoring of Radiofrequency Electromagnetic Field Exposure Levels from Mobile Phone Base Stations and Broadcast Transmission Towers by Car-Mounted Measurements around Tokyo“. Electronics 12, Nr. 8 (12.04.2023): 1835. http://dx.doi.org/10.3390/electronics12081835.

Der volle Inhalt der Quelle

Annotation:

Car-mounted measurements of radiofrequency electromagnetic exposure levels were carried out in a large area around Tokyo. Prior to the electric field (E-field) measurements using a car, the effect of the car body was evaluated in an anechoic chamber. The measurements between May 2021 and February 2022 were carried out within a radius of 100 km centering on Nihonbashi, Tokyo, with a measurement distance of about 13,800 km. The measurement results were averaged in the reference area mesh (1 km2). It was found that the E-field strengths of FM/TV frequency bands are lower than that of mobile phone base stations. It was also found that the E-field strength of only the 5G frequency band is approximately 20–30 dB lower than that of all mobile phone systems. However, note that it is possible to depend on the data traffic of 5G. The E-field strength of all bands is higher in Tokyo than in other prefectures. Additionally, repeated measurements were carried out to investigate the reproducibility of the measured E-field. The standard deviation is less than 3 dB along the same route, and a similar tendency of E-field strength by the car to the time-averaged results of spot measurements in the past was confirmed. Finally, the relationship of E-field strength with population density was investigated. It was found that the E-field strength from mobile phone base stations has a positive relationship with population density.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

45

Indalécio Pachón Mateos, Enrique, José Carlos Pachón Mateos Mateos, Ricardo Carneiro Amarante, Carlos Thiene Cunha Pachón, Tasso Júlio Lobo, Tomás Guillermo Santillana Peña, Juán Carlos Zerpa Acosta, Juán Carlos Pachón Mateos, Felipe Ortêncio und Christian Higuti. „Prevention of Esophageal Damage During Ablation of Atrial Fibrillation by the Esophagus Mechanical Deviation“. Journal of Cardiac Arrhythmias 32, Nr. 4 (16.04.2020): 278–90. http://dx.doi.org/10.24207/jca.v32n4.982_in.

Der volle Inhalt der Quelle

Annotation:

Atrial fibrillation is the most prevalent arrhythmia in the world population. Despite the use of antiarrhythmics, it is difficult to control clinically, causing symptoms and mainly generating risk of a thromboembolic event. Since 1998, by means of radiofrequency ablation, the treatment of atrial fibrillation has completely changed, but together with this important evolution complications from this ablative treatment technique have also started. In addition to the pulmonary vein stenosis caused by the ablation and later corrected with the change in the technique, atrioesophageal fistulas appeared due to the application of radiofrequency in the posterior wall of the left atrium. This wall is very close (0.5 cm onaverage) to the esophagus, which facilitates the formation of the fistula that leads to the death of almost 100% of the affected patients, despite the various treatment measurements already developed. To avoid this serious complication, several authors have created techniques to protect the esophagus including its mechanical deviation to a region opposite to the radiofrequency application, taking advantage of its mobility and easiness of handling. The mechanical deviation of the esophagus has proven to be the simplest, cheapest and most efficient way to protect this organ from radiofrequency thermal damage during atrial fibrillation ablation.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

46

Massardier-Pilonchery, Amelie, Elena Nerrière, Sophie Croidieu, Fabien Ndagijimana, François Gaudaire, Christophe Martinsons, Nicolas Noé und Martine Hours. „Assessment of Personal Occupational Exposure to Radiofrequency Electromagnetic Fields in Libraries and Media Libraries, Using Calibrated On-Body Exposimeters“. International Journal of Environmental Research and Public Health 16, Nr. 12 (13.06.2019): 2087. http://dx.doi.org/10.3390/ijerph16122087.

Der volle Inhalt der Quelle

Annotation:

Background and Objectives: With the spread of Wifi networks, safety concerns have arisen, with complaints of somatic disorders, notably in traditional libraries and media libraries. The aim of the present study was to describe the conditions and levels of exposure to radiofrequency electromagnetic fields in the real-life occupational conditions of those working in traditional libraries and media libraries. Methods: Dynamic measurements, using an exposimeter, were taken in 20 radiofrequency bands from 88 to 5850 MHz. The activity of 28 library workers was analyzed on a space-time budget. An audit of exposure sources and static measurements enabled the work-places to be mapped. Results: In seven libraries, 78,858 samples were taken over the 20 radiofrequency bands from 88 to 5850 MHz. Exposure was described for 28 working days. The median total field was 0.071 V/m (10th percentile: 0.022 V/m, 90th percentile: 0.534 V/m) and for Wifi the median field was 0.005 V/m (10th percentile: 0.005 V/m, 90th percentile: 0.028 V/m). Median individual exposure to Wifi frequency waves ranged from 0.005 to 0.040 V/m. Conclusions: Overall, the occupational exposure in this sector was close to the exposure in the general population. Peaks were due to the use of walkie-talkies by security staff. Exposure due to external sources depended on geographic location. Exposure in this occupation is well below the general occupational exposure levels, notably as regards Wifi.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

47

Roučka, Štěpán, Serhiy Rednyk, Thuy Dung Tran, Artem Kovalenko, Dmytro Mulin, Sunil S. Kumar, Petr Dohnal, Radek Plašil und Juraj Glosík. „Enthalpy of the N⁺ + H₂ → NH⁺ + H Reaction—Experimental Study of the Reverse Process“. Astrophysical Journal 959, Nr. 2 (01.12.2023): 127. http://dx.doi.org/10.3847/1538-4357/ad0bea.

Der volle Inhalt der Quelle

Annotation:

Abstract The formation of nitrogen hydrides in the interstellar medium is initiated by the nearly thermoneutral reaction of N+ + H2 → NH+ + H. Here, we experimentally determine the enthalpy of this reaction using the principle of detailed balance from a measurement of the rate coefficient of the reverse reaction NH+ + H → N+ + H2. The measurements were carried out in a linear radiofrequency 22-pole trap combined with an effusive beam source of atomic hydrogen at temperatures between 10 and 100 K. The resulting ground-state energy difference (or reaction enthalpy at 0 K) of ΔE 0 = (18 ± 4) meV confirms that there are no significant energy barriers on the reaction path.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

48

Chen, Francis F. „RF production of high density plasmas for accelerators“. Laser and Particle Beams 7, Nr. 3 (August 1989): 551–59. http://dx.doi.org/10.1017/s0263034600007539.

Der volle Inhalt der Quelle

Annotation:

Preliminary experimental results are shown on the production of plasmas by low frequency helicon waves. At constant rf frequency and power, the results show a maximum in density as the dc magnetic field is varied. The measurements confirm the theoretical expectation that the plasma is ionized by Landau damping of the radiofrequency waves.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

49

Solanki, Smit Bharat, Vineet Mishra, Nita Mishra, Sejal Ajmera Desai und Red Alinsod. „Transcutaneous Temperature-controlled Radiofrequency for Vaginal Rejuvenation“. Journal of Mid-life Health 15, Nr. 4 (Oktober 2024): 250–57. https://doi.org/10.4103/jmh.jmh_32_24.

Der volle Inhalt der Quelle

Annotation:

ABSTRACT Background: Vaginal laxity and sexual dysfunction are commonly experienced by women, but are typically stigmatized and considered inappropriate to discuss openly. This study was designed to assess the effectiveness and safety of transcutaneous temperature-controlled radiofrequency (TTCRF), in addressing these concerns. The study used a single-blinded randomized sham-control design. Aims and Objectives: The aim was to study the role of TTCRF for vaginal rejuvenation using subjective and objective measurements. Materials and Methods: Two hundred parous women were randomly assigned to either a treatment group (n = 110) or a sham group (n = 90). Participants who were between 35 and 55 years of age and reported complaints of vaginal laxity, as well as those who presented symptoms such as vaginal flatus or sexual issues, were included. The treatment group was administered TTCRF therapy, whereas the sham group had a placebo procedure to ensure blinding was maintained. The outcome measures included subjective assessments, such as the Female Sexual Function Index (FSFI), the Vaginal Laxity Questionnaire (VLQ), the Vaginal Flatus Score (VFS), and the Vaginal Laxity and Bother Score (VLBS), as well as objective measurements, such as the Modified Oxford Score (MOS) and the Genital Hiatus (GH) questionnaire. Results: Baseline characteristics were comparable between the groups. Significant improvements in FSFI, VLQ, and VLBS were noted in the treatment group compared to sham at 1 month, 3 months, and 6 months. The MOS improvements did not reach statistical significance, suggesting potential limitations in its use as an objective measure. VFS showed improvement in both the groups, indicating a potential placebo effect. No significant changes were observed in GH. Adverse events were mild and transient, with no serious incidents reported. Conclusion: Despite societal taboos, TTCRF demonstrated notable improvements in subjective measures of vaginal laxity and sexual dysfunction over a 6-month period. The safety and outpatient feasibility of TTCRF were established. The findings contribute to understanding the role of TTCRF in managing these sensitive concerns among women.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

50

Caffey, Sean, Edward McPherson, Brian Moore, Thomas Hedman und C. Thomas Vangsness. „Effects of Radiofrequency Energy on Human Articular Cartilage“. American Journal of Sports Medicine 33, Nr. 7 (Juli 2005): 1035–39. http://dx.doi.org/10.1177/0363546504271965.

Der volle Inhalt der Quelle

Annotation:

Background Previous radiofrequency work has not rigidly controlled energy application to the articular cartilage, giving uncertain results published to date. Hypothesis At minimal settings, radiofrequency probes cause cell death in measurable areas when applied to human articular cartilage. Study Design Controlled laboratory study. Methods Simulating operating room conditions, 5 commercially available radiofrequency probes were attached to a customized jig to standardize a minimal contact pressure of each probe tip to 2.0 g. Keeping all variables the same, probes were placed on specific points of fresh grade II human cartilage with treatment times of 1 and 3 seconds at the manufacturer's recommended settings. Grade III cartilage was also tested with a treatment time of 3 seconds, and grade II cartilage was studied with the probe held 1 mm off the cartilage surface. Cartilage was blindly analyzed by confocal microscopy using a live/dead cell viability assay to determine the extent of cell death. Results Radiofrequency probes produced significant cellular death in the form of a half-circle into the cartilage to variable depths. For treatment times of 1 and 3 seconds, cell death measurements ranged from 404 to 539 μm and 1034 to 1283 μm, respectively. One probe failed to show any effect, with minimal evidence of cell death or cartilage smoothing. When probes were kept a 1.0-mm distance above the cartilage, no cell death or cartilage smoothing was noted. Radiofrequency treatment of grade III cartilage penetrated to the subchondral bone. There was no statistically significant difference between the damage caused by monopolar and bipolar probes when tested under these rigidly controlled conditions. Conclusion These results showed significant cellular death at these minimal conditions to the underlying chondrocytes with radiofrequency probes. Surgeons using this technology need to be aware of the power and dangerous potential these probes can have on articular cartilage.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Wir bieten Rabatte auf alle Premium-Pläne für Autoren, deren Werke in thematische Literatursammlungen aufgenommen wurden. Kontaktieren Sie uns, um einen einzigartigen Promo-Code zu erhalten!