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Fluorescence, Decay Time, and Structural Change of Laser Dye Cresyl Violet in Solution due to Microwave Irradiation at GSM 900/1800 Mobile Phone Frequencies  [PDF]
Fuat Bayrakceken,Korkut Yegin
International Journal of Photoenergy , 2012, DOI: 10.1155/2012/965426
Abstract: Microwave irradiation at GSM 900/1800?MHz mobile phone frequencies affects the electronic structure of cresyl violet in solution. These changes are important because laser-dye cresyl violet strongly bonds to DNA- and RNA-rich cell compounds in nerve tissues. The irradiation effects on the electronic structure of cresyl violet and its fluorescence data were all obtained experimentally at room temperature. For most laser dyes, this is not a trivial task because laser dye molecules possess a relatively complex structure. They usually consist of an extended system of conjugated double or aromatic π-bonds with attached auxochromic (electron donating) groups shifting the absorption band further towards longer wavelength. Because of the intrinsically high degree of conjugation, the vibrational modes of the molecular units couple strongly with each other. We found that the fluorescence quantum yield was increased from to due to intramolecular energy hopping of cresyl violet in solution which is exposed to microwave irradiation at mobile phone frequencies, and the photonic product cannot be used as a laser dye anymore. 1. Introduction Cresyl violet (Figure 1) is often used as a staining agent for studying the changes on DNA- and RNA-rich compounds in tissues. Especially, the effects of microwave radiation on blood-brain barrier permeability heavily rely on cresyl violet based stain analysis, simply because laser dye molecules are often distinguished due to their relatively complex structure in photoluminescence data. However, effects of microwave irradiation on cresyl violet in solution have not been studied in detail, and changes in the absorption band due to microwave irradiation are particularly important for widespread applications of laser dye cresyl violet. Figure 1: Molecular structure of cresyl violet. The photophysical and chemical behaviors of cresyl violet are strongly influenced by electrostatic, hydrogen-bond, and acid-base interactions in solution, as well as by its hydrophobicity [1]. The rotational relaxation of a solute molecule depends on its environment, especially for the case of ionic and polar solute species embedded in electrolyte solutions [2–5]. In such cases, solute-solvent electrostatic interactions can significantly influence the behavior of the solute. Dramatic changes in the local solvent structure and the solute dynamics occur for ionic solute molecules. Laser dyes are organic compounds that relax radiatively after optical excitation, emitting in the UV-visible or IR range [6]. Today a large variety of luminescent dyes have been
Multiband Fractal Planar Inverted F Antenna (F-Pifa) for Mobile Phone Application
Norlyana Azemi Saidatul;Azremi Abdullah Al-Hadi Azremi;Raad Badlishah Ahmad;Ping Jack Soh;Fareq Malek
PIER B , 2009, DOI: 10.2528/PIERB09030802
Abstract: The design of a novel Fractal planar inverted F antenna (F-PIFA) based on the self affinity property is presented in this paper. The procedure for designing a Fractal Planar Inverted F Antenna is explained and three different iterations are designed for use in cellular phones. The F-PIFA has a total dimension of 27 mm x 27 mm and has been optimized to be operational at GSM (Global System for Mobile Communication), UMTS (Universal Mobile Telecommunication System) and HiperLAN (High Performance Radio LAN) with the frequencies range from 1900 MHz to 2100 MHz, 1885 to 2200 MHz and 4800 MHz to 5800 MHz respectively. The antenna achieved -6 dB return loss at the required GSM, UMTS and HiperLan frequencies with and has almost omnidirectional radiation pattern. This antenna has been tested using realistic mobile phone model and has met the performance criteria for a mobile phone application. Simple semiempirical formulas of the operational frequency, numerical calculation and computational SAR of the antenna also has been presented and discussed.
Implementation of Intelligent Polling System Using GSM Mobile  [PDF]
Monali R.Dave,, Jai Karan Singh , Mukesh Tiwari , Dr. Anubhuti Khare
International Journal of Computer Technology and Electronics Engineering , 2011,
Abstract: An E-voting, Electronic voting systems, also known as Personal Response Systems (PRS), Audience Response Systems (ARS) or classroom communication systems (CCS) use handsets as transmitter if the person is within the range of receiver or uses GSM Mobile Equipment (ME) to reply from anywhere. To minimize the disadvantages of generic e-voting, we propose a method in which a voter, who has wireless certificate issued in advance, uses its own GSM Mobile phone without a special registration for a vote. In this paper, a polling scheme using GSM mobile technology is resented as most basic application of GSM based Personal Response System, which allows a voter to cast his vote in simple and convenient way without the limit of time and location. By integrating an electronic voting scheme with the GSM infrastructure
Effects of Mobile Phone System (GSM-900) on the Rabbit Hearing with Auditory Brainstem Response
Ali Khavanin,Parvin Najafi,Abbas Rezaee,Hossin Bakhtou
Journal of Biological Sciences , 2007,
Abstract: A rapid worldwide expansion of mobile telephones raises questions regarding possible effects of the emitted radiofrequencies on the health of the consumers. The mobile phone system (GSM-900) works in the range of 890-960 MHZ in the electromagnetic spectrum. The present study was performed to investigate the effect of mobile phone radiation on auditory system of rabbit. The auditory brainstem response (ABR), was studied before and after using a mobile phone in the hearing of rabbit. After measuring of click and tone burst at different frequencies (500, 1000, 2000, 4000 and 8000 HZ) with two intensities of 70 and 100 dB, the animals were exposured to electromagnetic waves from a simulator of mobile phone one week exposure and 16-19 h rest. The ABR tests were shown that the latency time of wave V (ms) have some changes in the frequencies of the experiments. The latency time of wave V (ms) at the frequencies of 500 and 1000 HZ was almost unchanged, but at the frequencies of 2000, 4000 and 8000 HZ were decreased at the end of second week of exposure. Statistical analysis have not any significant changes between time latency of wave in pre and post exposures.
Short GSM mobile phone exposure does not alter human auditory brainstem response
Gábor Stefanics, Lóránd Kellényi, Ferenc Molnár, Gy?rgyi Kubinyi, Gy?rgy Thuróczy, István Hernádi
BMC Public Health , 2007, DOI: 10.1186/1471-2458-7-325
Abstract: Auditory Brainstem Response (ABR) was recorded with three non-polarizing Ag-AgCl scalp electrodes in thirty young and healthy volunteers (age 18–26 years) with normal hearing. ABR data were collected before, and immediately after a 10 minute exposure to 900 MHz pulsed electromagnetic field (EMF) emitted by a commercial Nokia 6310 mobile phone. Fifteen subjects were exposed to genuine EMF and fifteen to sham EMF in a double blind and counterbalanced order. Possible effects of irradiation was analyzed by comparing the latency of ABR waves I, III and V before and after genuine/sham EMF exposure.Paired sample t-test was conducted for statistical analysis. Results revealed no significant differences in the latency of ABR waves I, III and V before and after 10 minutes of genuine/sham EMF exposure.The present results suggest that, in our experimental conditions, a single 10 minute exposure of 900 MHz EMF emitted by a commercial mobile phone does not produce measurable immediate effects in the latency of auditory brainstem waves I, III and V.There are about 1.6 billion GSM mobile phones (MPs) in use throughout the world today. Due to the close proximity of the antenna of the mobile handset to the user's ear and head, the brain is inevitably exposed to EMFs with a relatively high specific absorption ratio (SAR). Results of experimental radiofrequency (RF) dosimetry indicate that approximately 40–55% of the mobile phone's RF output power energy is absorbed in the users head [1]. Due to the high number of MP users and the relative high SAR close to the ear, it is important to resolve whether or not EMF exposure by MPs can adversely affect the human hearing system.Numerous studies have investigated the electrophysiological effects of EMF exposure in humans. A significant delay in the latency of the fifth wave (V) of the ABR after 15 min of exposure to EMF emitted by a GSM MP was recorded [2] and the authors suggested that the observed delay might lead to a temporary 15–18 dB he
Evaluation of the Interference of the Microwave Radiation Emitted from GSM Mobile Phones on the Performance of Cell Counters
Bahaedini ,N.,Atefi, M.,Mortazavi, S.M.J
Medical Laboratory Journal , 2009, DOI: http://www.goums.ac.ir/mljgoums/index.php?&slct_pg_id=10&sid=1&slc_lang=en
Abstract: Background and Objectives: Incidents related to electromagneticinterference with medical devices have been reported over the past decades.It has also been indicated that the microwave radiation emitted from mobilephones interferes with the operation of medical devices; therefore, this studyaimed at testing the interference by GSM mobile phones with cell counters.Material and Methods: We did this experimental Study on thirty-twoheparinized blood samples of 32 healthy individuals Selected randomly. TheCell Counting was Carried out in the presence of Electro magnetic fieldproduced by three Cell phones with different levels of SAR (Low,intermediate and High) and without being in electromagnetic field.Statistical tests were used to analyze the data (p<0.05).Results: Microwave radiation emitted from cell phones, regardless of theirSAR, interferes with the proper operation of cell Counter. This interferenceleads to false Counting.Conclusion: As mobile phones emit microwave radiation in an isotropicmanner, keeping mobile phones at a safe distance, 15cm, from medicalequipments will be necessary. These observations confirm the need for somerestrictions of mobile phone use in hospitals and medical laboratories.Key words: Interference, Cell Counters, Mobile Phone, MicrowaveRadiation
Designing Asian-Sized Hand Model for SAR Determination at Gsm900/1800: Simulation Part
Suzanna Harun Ronald;Mohd Fareq Bin Abd Malek;Syed Hassan Idris;Ee Meng Cheng;Mohd Hafizuddin Mat;Muhammad Solihin Zulkefli;Siti Fazlina Binti Maharimi
PIER , 2012, DOI: 10.2528/PIER12050304
Abstract: A simple geometrical Asian-hand model with human tissue properties posed at two common talk-mode positions is proposed for comparative study. The newly designed hand is formed by measuring adult female hand at open-hand position before being posed into the presented styles. Four human hand tissues are included; skin, bone, muscle, and tendon, and also three homogeneous set of hands using specific anthropomorphic mannequin (SAM) hand phantom dielectric properties. A candy-bar type mobile phone with Planar Inverted-F Antenna (PIFA) is used to radiate dual-band frequency of GSM900/1800 in the vicinity of the SAM head phantom. The mobile phone casing is made out of plastic and only two components were considered: the FR-4 ground plane and PIFA. The specific absorption rate (SAR) averaged over a mass of 10 gram and 1gram is calculated after obtaining the power loss density and electric field value from simulation in CST Studio Suite 2011. The SAR and return loss results of six hand structures, including the SAM hand phantom are compared. The antenna performance with the inclusion of hand does not decrease as much as 1800 MHz in 900 MHz range, but absorbs energy more in the hands for 1800MHz compared to 900 MHz SAR values.
Subscribers’ Complaints and Response of the Global Satellite Mobile (GSM) Network Operators in Nigeria
SB Isiaka
African Research Review , 2010,
Abstract: Global Satellite Mobile (GSM) network was introduced into Nigeria in 2001 amidst various challenges that have serious effect on the quality of the services. The most serious among these challenges is the epileptic power supply. The GSM subscribers on their part also face many problems, major of which is constant network failure. Other problems include card recharging problem; checking of balance difficulty and wrong deduction of credit. The study was therefore designed to examine how the GSM Network operators respond to the complaints of the Subscribers. Implications and consequences of the subscribers’ complaints on the providers were discussed. Both primary and secondary sources were used in obtaining relevant data and information. The primary source includes questionnaire and personal interaction. The secondary source includes the historical background of GSM in Nigeria; relevant extracts from current News Magazines and review of related literature. Selected GSM Operators in Nigeria were used as case study. Based on the findings, the paper recommends ways to tackle subscribers’ complaints. These recommendations were categorized into four- To the GSM Providers; To the Government; To the GSM regulatory body in Nigeria; and to the Subscribers.
A Mobile Micropayment Scheme Based on GSM

YANG Zong-Kai,FU Xiong,LANG Wei-Min,WU Shi-Zhong,

计算机科学 , 2005,
Abstract: In this paper,we propose a micropayment scheme designed for use in a GSM mobile environment,where the overload of computation,storage and communication for mobile phone is reduced by directing operations normally per- formed by the mobile user to the static portion of the network. Messages received and sent during the payment are very simple and public key infrastructure is not needed,which reduces delay and removes the possibility of incomplete payment protocols due to communications failures. Furthermore,all the information with regard to payment is en- crypted by a shared symmetric key in our scheme,where the privacy of the mobile user is protected and the security of information is guaranteed. Compared with other mobile micropayment schemes in existence,no public-key operation is required, which minimizes the computation and storage overhead dramatically. In addition, restricted anonymous is provided in our scheme.
Estimation Of Mobile Positioning For Lbs Using Gps-Gsm Technology  [PDF]
International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering , 2013,
Abstract: Location estimation using the Global System for Mobile Communication (GSM) is an emerging application that infers the location of the mobile receiver from multiple signals measurements. The approach is based on the use of an inherent feature of the GSM cellular system and on the use of this information to estimate the phone’s location. Mobile positioning is the key aspect in providing the location based services. To offer reliable Location Based Services (LBS) of 3G communication, accurate position estimate of Mobile Station (MS) is essential. In the present technology, there is various position techniques are based on estimation of either time, angle and are economic. This work presents a new simple approach, to find MS position using Received Signal Strength (RSS) measurements and is based on pdf of RSS probability method which in turns results with improved accuracy and reduction in minimum mean square error (MMSE). It turns out to be significantly beneficial, enhancing estimation accuracy and thereby enabling high-performance mobile positioning in a practical and cost effective manner. Experimental observed results are verified with Global Positioning System (GPS) receiver measurements and found reasonably matching.
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