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Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Radiofrequency electromagnetic fields (RF-EMF) exposure is increasing in various areas of life. In our study, we investigated the effects of 5G (6 GHz, 0.083 W/kg SAR) RF-EMF on the ratio of vitality, apoptotic (the early/late) and necrotic in rat blood cells. In our study, 10 Wistar Albino male rats were used weights range between 250-300g. Before RF-EMF applications, blood samples (2cc) were collected from all rats by cardiac puncture method. These rats were selected as the control groups. The same rats, by placing in the special application cage were exposed to the 6 GHz RF-EMF application for 4 hour/day during 6 weeks. After RF-EMF applications, blood samples (2cc) were recollected from the same rats. These rats were selected as the radiofrequency radiation (RFR) groups. Flow cytometric analysis in which annexin-V kit used, was performed to determine the percentage the ratio of viable, the early/late apoptotic and necrotic cell. The ratio of % viable cells were increased in the RFR group by compared to the control group, the ratio of % cells in the early apoptotic and necrotic decreased and this between the two groups difference was statistically significant (p<0.05). However, there were no statistically meaningful differences between groups by compared to the ratio of % cells in the late apoptotic. As a results of 6 GHz RF-EMF, had significant effects on vitality, apoptotic and necrotic in blood cells. while it supported to the ratio of vitality, were inhibited the ratio of apoptotic and necrotic. [ABSTRACT FROM AUTHOR]

In operational analysis studies; it is possible to model and simulate at an engineering level, engagement level, task level and campaign forces level. In this study, modelling and simulation studies are performed in engagement-level allowing the analysis of air-to-ground engagement effectiveness of fighter aircraft according to the operational environment. The operating environment of the combat aircraft, which provides survivability analysis based on low visibility and electronic mixing capabilities, is created. The search radar and tracking radar models for ground-to-air threats have been designed in accordance with the engagement level. The dynamic model of the fighter aircraft and the ground-to-air missile have been modelled using pseudo 5 degree-of-freedom. Modelling has been carried out to allow the use of changes in the Radar Crosssectional Area (RCS), which is one of the most important factors affecting the survivability of the aircraft, with respect to azimuth and elevation angles. The Radio Frequency (RF) jamming capability of the fighter aircraft has also been modelled in accordance with the engagement level. The results of the generic scenarios for the analysis of the effect of these models' parameters on the survivability of fighter aircraft have been presented. [ABSTRACT FROM AUTHOR]

In this study, unsulfured, sulfured (1kg ton-1 and 2kg ton-1 sulfur) and extract (pistachio vera green hull extract) treated apricots were dried using an innovative combined solar-assisted air pre-drying and air-assisted radio frequency drying system. The obtained dried apricots were compared with unsulphured and sulphured apricots dried by the conventional sun drying during storage. The effects of three different storage temperatures (5, 20 and 35°C) on color values (CIELAB, L*, a* and b*) and color properties (chroma, hue angle value, total color change, browning index and browning value) of six different dried apricots obtained by different pre-processes and technologies were examined. The results showed that while there was no significant change in L*, a* and b* values of the sulphured samples during storage at 5 and 20°C, there was a significant change in these values at 35°C. A significant change was observed in L*, a* and b* values of unsulphured products at all temperatures. A similar trend was observed for the color intensity and browning index values of the products. As a result of the kinetic studies applied for the browning reactions of the products, it was determined that these reactions were dependent on the storage temperature and increased at high temperatures. The browning reaction rate constant (zero order) for apricots treated with pistachio hull extract and sulphur was found as 0.0006 and 0.0009 weeks-1 at 5 and 20°C, respectively. With the temperature increasing to 35°C, this value was found to be 0.1786 weeks-1, which indicates that browning reactions increased significantly at this temperature. The results showed that drying in the combined drying system contributes to the color quality of dried apricots during storage at 5 and 20°C, even at low sulfur concentrations compared to drying under the sun. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, in order to determine the radiofrequency electromagnetic field (RF-EMF) level exposed in the home environment and to model its change, 24-hour RF-EMF measurements were performed in the frequency range of 100 kHz to 3 GHz. In measurements, the highest RF-EMF value was recorded as 17.31 V/m, which is below the limit values determined by ICNIRP and BTK. In measurement locations that are in line of sight with the base stations, the RF-EMF value changes according to the measurement time. The RFEMF value measured in the afternoon is about 32% higher than at night. Statistical analysis of data showed that the long-term RF-EMF can be best expressed by Burr distribution. Unlike the studies in the literature, the change of RF-EMF during the day was examined and a new mathematical model was proposed. With the proposed model, the change of 24-hour RF-EMF during the day in the home environment can be determined with accuracy of up to 95% without the need for measurement using only 6-hour RF-EMF value. [ABSTRACT FROM AUTHOR]

Copyright of Pamukkale Medical Journal is the property of Pamukkale Journal of Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Radiofrequency, as a safe, effective and tolerable treatment option, come into prominence of aesthetic applications in the last period. Radiofrequency devices produce focal thermal damage to the dermis by electric current-generated heat. This focused energy preserves the epidermis and is associated with fewer complications and side effects and quicker recovery time. Contrary to lasers, the effect is independent of chromophores, so they can be used safely in all skin types. Although the results have overall been favorable, many of the studies are nonrandomized, noncomparative trials based on subjective evaluation. The ideal treatment parameters, the energy levels and the number of passes for optimal results have not been determined yet. Radiofrequency applications in face and neck aesthetics are reviewed with the current literature in this article. [ABSTRACT FROM AUTHOR]

Almost all of the population of our country is at risk of earthquakes and it is of great importance that the structures are constructed to be earthquake resistant. Iron and concrete designs are the main determinant parameters of earthquake resistance of buildings. Although the ready-mixed concrete system has become widespread in our country and improvements in concrete quality have been achieved, the fact that we encounter more damage in similar earthquakes compared to developed countries shows that we have not achieved the desired quality yet. For this purpose, in order to prevent abuse of ready-mixed concrete inspections of buildings constructed by The Ministry of Environment and Urbanization (MEU) within the scope of building inspection, a system for monitoring concrete samples electronically (EBIS) was put into use for the first time in the world. In this study, in 2019, all the results which were tested in Isparta province were sampled and evaluated. The samples used consist of 12650 ready-mixed concrete samples in C25/30, C30/37, C35/45 concrete classes, all of which were taken with Radio Frequency Identification (RFID) tags. Although the results obtained show that there is no problem in the compressive strength results of ready-mixed concrete used in controlled buildings in Isparta, points to be considered in concrete quality have been encountered and these issues have been emphasized. [ABSTRACT FROM AUTHOR]

Nowadays firms must ensure effective flow of information with all stakeholders as a part of the supply chain in order to be successful as well as to establish their corporate systems well, integrate their internal processes and continue their activities efficiently. In food supply chains; in the process from farm to fork, the need for an effective supply chain management is remarkable on account of the ambient parameters pose a risk to human health due to food safety, short shelf life and variable quality criteria of foods. As advantages of information technologies usage; food supply chain will be transparent and enables traceability, food safety will ensure and food quality will maintain. In this article, the principles of enterprise resource planning (ERP), radio frequency identification (RFID), Internet of Things (IoT) and blockchain systems from information technologies and their applications in the food industry are examined. [ABSTRACT FROM AUTHOR]

In recent years, the rapid development of wireless technologies has increased the need for frequency spectrum usage. To overcome this problem, Cognitive Radio (CR) has emerged as a new technique which enables the use of free ranges in the frequency spectrum. Cognitive radio networks (CRNs) are based on the principle of benefiting from the empty spectrum of secondary users (Sus) by using sensing techniques and analyzing frequency ranges. Although the frequency spectrum is used by various technologies, some frequency ranges are used inefficiently and inadequately. Fixed spectrum allocations cause unused frequency channels in the radio frequency spectrum. Spectrum detection, which is one of the features that cognitive radio applies to reduce the inefficiency of spectrum usage, scans all the primary users (PUs) in the spectrum area and the empty frequency bands. In this study, a method has been proposed to detect unused stationary frequency bands and to use these frequency bands effectively. This method, which is named as matched filter detection, was examined in AWGN channel and its results were evaluated in MATLAB. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate printing techniques used in electronic textile applications and to examine the application conditions, advantages and disadvantages of the conductive inks used in these printing processes. This research is a conceptual framework designed to examine conductive inks within the scope of electronic textiles and their importance. In the study, it is seen that by printing of silver doped conductive ink on flexible materials, radio frequency identification (RFID, electromyography (EMG) and variety of sensors are designed. It was evaluated that screen printing and inkjet printing techniques are most familiar printing applications. [ABSTRACT FROM AUTHOR]

Computers are devices that facilitate our work in making people spend a long time by their jobs seconds. Robots have started to come to the forefront in the development of the computer. Robots today, less manpower utilization, prevent the entry of people in jeopardy, less cost, faster, and are used for purposes such as quality production. Labrot-I is designed for use in the laboratory. In this study, the mobility feature was added to a robot arm. Then, RF communications with the robotic arm and mobility check is performed. the holder of the robot is also provided to be parallel to the ground in certain axis.Labrot-I was desined to be extendable. [ABSTRACT FROM AUTHOR]

Thawing techniques have an important role in processing of frozen foods. Frozen products are generally thawed by means of using air circulation, water or condensing steam under vacuum in the food industry. Thawing foods by conventional techniques may have some disadvantages. Novel thawing techniques such as high pressure thawing, microwave thawing, radio frequency thawing and ohmic thawing are used to eliminate the disadvantages of conventional thawing. It is reported that high pressure thawing causes minimal changes on the flavor, color and nutritional values, and reduces thawing time and drip loss. Microwave and radio frequency thawing generate volumetric heat within the product. These systems significantly reduces thawing time and drip loss. Ohmic thawing technology improves textural properties and causes a very few changes in textures. Since novel thawing techniques applied in food industry do not constitute overheating during thawing foods, and could shorten thawing time. They provide high retention of food nutrients besides functional and sensory properties of foods. [ABSTRACT FROM AUTHOR]

Similar to the other electromagnetic waves, radio waves consist of oscillating electric and magnetic field as well. Due to the effect of the applied electric field constituent of radio waves, heat is volumetrically generated within the food material as a result of the molecular friction of oscillating molecules and ions. The heating process that applied on food materials via the use of radio frequency is called "dielectric heating". Radio frequency (RF) heating is regarded as a promising technology for food applications due to its associated rapid and uniform heat distribution, large penetration depth and lower energy consumption properties. In recent years, RF heating technology is widely used in food industry for the purposes such as cooking/ baking, thawing, freezing, pasteurization, sterilization, disinfestation and drying. In this study, the common use of RF heating in food processing and the advantages or disadvantages of its use are investigated, and information related to the history and the heating principles of RF technology are given in details. [ABSTRACT FROM AUTHOR]

Objective: The aim of present study was to investigate the probable effects of 900 MHz radiofrequency (RF) radiation on rat lymphocyte subgroup percentages and activation markers on the lymphocytes in vivo. Material and Method: Twenty-two weeks old Sprague Dowley rats were divided into four groups as: short study, short control, long study and long control (1-4). A final number of 13 rats per group were approved for analysis from 15 rats pet group because of infection and technical problems. Short and long study groups were exposed to 900 MHz RF radiation for 1 week and 4 weeks respectively, 5 days a week, 30 minutes each day. The corresponding short and long control groups were exposed to the same conditions for the same time like study groups, except RF exposure. After this procedure, total leucocytes/ml, lymphpocyte subgroups' percentages, and the percent of activated lymphocytes were detected by flow cytometry. Serum cytokine levels were measured for determining the Th1 or Th2 dominant response in the same rat groups. Results: Total leukocyte counts, CD3, CD4, CD8 percentages and CD45RA and CD25 lymphoqyte activation markers, and serum levels of IL-4, IL-10, TNF-α and IFN-γ levels were not significantly different among the short and long term RF and corresponding short and long control groups. Conclusion: Our results show that RF exposure of one month does not influence the lymphocyte percents and activations KS well KS Th1 or Th2 response. [ABSTRACT FROM AUTHOR]

Simulation and experimental carrier frequency offset (CFO) tracking performances of conventional adaptive equalization algorithms have been evaluated in real-time WiMAX (IEEE 802.16-2004) radio channels in this paper. Instead of using a certain type of channel profile this study concentrates on true frequency selective Rayleigh fading channels in WiMAX radio environment around 3.5 GHz. Bit Error Rate (BER) performances of the most commonly used conventional equalization techniques; Least Mean Squares Decision Feedback Equalizer (LMS-DFE) and Recursive Least Squares DFE (RLS-DFE) algorithms are investigated in study. The simulation results have demonstrated that the simulation and experimental performances are compatible with each other and extremely satisfying. [ABSTRACT FROM AUTHOR]

Radiofrequency ablation (RFA) is a relatively new technique for breast cancer treatment. In spite of the increasing literature about RFA, there is limited experience in breast cancer treatment. According to the results of a few clinical studies, even if RFA is preferable as a minimally invasive procedure in cases with localised small sized tumors (T1), there are a few obstacles to overcome. The studies have stated that the histopathological knowledge and information was lost by postablation damage and there is an absence of standardization of care in follow-up. In order to consider RFA as a treatment option in breast cancer, there is a need for long-term follow-up research studies including a higher number of patient enrollment. [ABSTRACT FROM AUTHOR]

Objective: Chronic atrial fibrillation (AF) is a frequent arrhythmia in patients undergoing open-heart surgery. In this study, we compared the results of irrigated monopolar and bipolar radiofrequency (RF) ablation in the surgical treatment of AF. Methods: Sixty-three patients with chronic AF, who underwent open cardiac surgery and concomitant irrigated RF ablation between October 2004 and January 2006, were retrospectively studied in two groups. Group 1 included 31 patients (22 female, 9 male), who underwent monopolar RF ablation, and Group 2 included 32 patients (18 female, 14 male), who underwent bipolar RF ablation. All patients received amiodarone during the first 6 months after surgery. Rhythm status of patients after RF ablation was followed-up postoperatively in the intensive care unit, on the day of discharge, and at their follow-ups with electrocardiography. In patients with a documented sinus rhythm (SR) at follow-up, the presence of atrial transport function was assessed with transthoracic echocardiography. Statistical analyses were performed by using t-test for independent samples, Chi-square test and McNemar's test. Complication-free survival during follow-up was evaluated using Kaplan-Meier analysis. Results: There was no hospital mortality in both groups. One patient from Group 1 had non-cardiac mortality (colon carcinoma). While in monopolar ablation group SR was documented in 83.3% of patients at a mean follow-up period of 11.5±4.0 months (between 4-18 months), 68.8% of patients from bipolar ablation group was in SR at a mean follow-up period of 9.3±3.0 months (between 4-15 months). In patients with docu kullamented SR during follow-up visits, atrial transport function was 76.6% in cases undergoing monopolar ablation, whereas it was 72.7% in cases undergoing bipolar ablation (p=0.797). Pacemaker implantation was performed in one (3.4%) patient from Group 1 after hospital discharge and in one (3.1%) patient from Group 2 during hospital stay. Conclusion: Irrigated monopolar and bipolar RF ablation are both safe and effective in terms of restoring SR and atrial transport function in patients with chronic AF, who underwent open cardiac surgery. [ABSTRACT FROM AUTHOR]

Electromagnetic (EM) fields are generated by several natural and man-made sources. Part of the electromagnetic spectrum called Radiofrequency (RF; 10 kHz - 300 GHz) is used in communications, mobile phones, radio and television broadcasts, etc. Extremely Low Frequency (ELF; 0 - 300 Hz) region of the spectrum is radiated by transformers, high power lines, household or working area appliances, and by the electrical goods. The use of electromagnetic waves increases due to the technological improvements, therefore, people are exposed to high levels of electromagnetic fields in their daily lives. The health priority of public concerns occurred about the mobile phones, base stations and wireless technologies. Furthermore, the sensitivity of the public is increasing on their adverse effects on the human health. The biological and health effects of EM radiation have been investigated for more than 25 years in Biophysics Department at Gazi University. In this study, the sources and the effects of EM fields along with the studies performed in Gazi Biophysics are summarized, and Gazi Non-Ionizing Radiation Protection Center (GNRK), the first scientific center founded to measure EM fields, is introduced. [ABSTRACT FROM AUTHOR]

Oxide ceramics include alumina, zirconia, silica, aluminum silicate, magnesia and other metal oxide based materials. Oxide ceramics have high melting points, low wear resistance, and a wide range of electrical properties. Oxide ceramics are used in a variety of applications. Examples include chemical and materials processing, electrical and high voltage power applications, Radio Frequency (RF) and microwave applications, and foundry and metal processing. "Zirconia-Ceramic steel?" The title of the first scientific paper to highlight the possibilities offered by the "transformation toughening" mechanism which occurs in certain zirconia ceramics. Since the publication of this seminal work in 1975, considerable research, development, and marketing efforts have been expanded on this single material which offer the traditional ceramic benefits of hardness, wear resistance and corrosion resistance, without the characteristic ceramic property of absolute brittleness. Zirconia, ZrO2 exists as a monoclinic crystal at room temperature inverting to tetragonal phase above approximately 1200°C. The addition of large amounts of a stabilizer such as magnesium oxide will induce a cubic crystal structure during firing that does not revert to the monoclinic phase upon cooling. The addition of generally less than 10% by weight of stabilizers yields high-density ceramic bodies known as transformation toughened zirconia. Two fundamentally different microstructures exist depending upon the added stabilizer. The addition of MgO yields a relatively coarse grained (50-100 micron) microstructure known as Mg-PSZ. The grains are predominantly cubic morphology with a fine precipitate of tetragonal phase dispersed within the grain. Yttria, Y2O3, additions yield an extremely fine grained (less than 1 micron) microstructure known as Y-PSZ or TZP or tetragonal zirconia polycrystal. The individual grains are completely tetragonal. In present study, Calcia and Magnesia stabilized fine Zirconia powders in various ratios were studied. Powder mixtures (Ca(OH)2, Mg(OH)2 and ZrO2) were prepared in acetone and milled as wet with YSZ (yitria stabilized zirconia) balls of 10 mm Ø for 3 h. Particle size of Calcia, Magnesia and Zirconia powders were submicrometer. The pressureless hot molding technique has been selected for forming of the partial stabilized zirconia with MgO and CaO. Binder system for pressureless hot molding was a mixture of paraffin wax as primary binder and oleic acid as surfactant. … [ABSTRACT FROM AUTHOR]

The technology of identifying the objects with radio frequencies firstly came into view after 2nd World War but it was used as the system after 1960's. Thanks to this technology, it has become possible to apply the activities more efficiently, while following the product movements faster and more reliably and avoiding the obstacles in activities. Under given price conditions, the ability of the management to obtain more output with its owning means a decrease in the unit costs and an increase in the unit contribution margin, in private, and means an increase in the added-value (productivity), in general . The aim of this study is putting forward the dimensions of cost reduction, that will be created by the increase in efficiency, which will be provided by the using of RFID technology and revealing this technology's effects on management results, by introducing the RFID technology, its components and their functioning. [ABSTRACT FROM AUTHOR]

Hepatocelluler carcinoma is common especially in Asia and Far East where the incidence of viral hepatitis is very high. Treatment of HCC includes the treatment of underlying chronic liver disease caused by viral hepatitis and the tumor itself. Although, surgical resection is the curative treatment procedure for the disease, presence of cirrhosis hinders the resection at about 90% of patients. Besides, owing to diffuse and multiple lesions, most of the patients are not suitable for the curative resection. Liver transplantation can cure both the underlying chronic liver disease and the HCC. Liver transplantation are performed according to expanded criteria and successful results have been obtained at our center. Local and ablative treatments are put on to the agenda in patients whom are not suitable for surgical intervention. Transarterial chemoembolisation (TACE), percutaneous alcohol injections (PAI) and radiofrequency ablation (RF) are the most common procedures that are effective in small solitary lesions. Systemic chemotherapies are used in the case of extrahepatic dissemination or in patients with unresectable disease. Cisplatin, doxorubicin, etoposite and 5-flourouracil have been used both as a single agent and in combinations but the response rates are limited between 8 to 18%. In this group of patients although the higher response rate was achieved with the combination of cisplatin, interferon-α-2b, doxorubicin and 5-flourouracil (PIAF), no survival advantage was obtained when compared with doxorubicin. This combination has not been accepted as a standard because of its severe morbidity. Recently sorefenib, a Raf kinase intibitor, was shown to be effective in HCC. Owing to survival advantage in a phase III trial when comparing to placebo, sorefenib seems to be proming agent in HCC. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of InformaticsTechnologies is the property of Institute of Informatics, Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Brachial plexopathi developing after radiotherapy is a rare but severe complication. There are various treatment modalities with limited success rate. To the best of our knowledge, there is no report of radiofrequency thermo coagulation application in brachial plexopathi treatment which is a successful method for control of chronic pain. The present case report presents stellate ganglion radiofrequency application in a case of brachial plexopathi which developed after radiotherapy and resistant to treatment. There were no complications apart from Horner syndrome which developed within 48 hours after application and disappeared spontaneously. As a conclusion, the present case report suggests that stellate ganglion radiofrequency application may be considered as a safe and effective mode of control of pain in such early-phase brachial plexopathi cases. [ABSTRACT FROM AUTHOR]