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Occupational Noise Exposure Evaluation in Drivers of Bus Transportation of Tehran City
P Nassiri,M Monazam Esmaeelpour,A Rahimi Foroushani,H Ebrahimi
Iranian Journal of Health and Environment , 2009,
Abstract: "n "nBackgrounds and Objectives: Noise in large cities is considered by the World Health Organization to be the third most hazardous type of pollution. Buses are an interesting object of study in the theme of noise pollution. They are at the same time a source of urban environmental (traffic) noise and occupational noise exposure source for drivers. The object of this study is Occupational noise exposure evaluation in drivers of bus transportation of Tehran city."nMaterials and Methods: Noise levels in 90 buses were sampled in three separate sub-sample including (1)30 Ikaroos buses (2)30 Man buses (3)30 Shahab buses, which were selected by simple random sampling. Noise exposure level was normalized to a nominal 8-h working day (LEX, 8h). Simultaneous Octave Frequency Analysis were measured and sound intensity level (SIL) for bus drivers were calculated. Results, which are obtained from separate buses were compared together and too with standard levels."nResults: the normalized noise exposure levels (LEX, 8h) in Ikaroos bus drivers(82dB A) were higher than that of in in Man bus drivers (77/6dB A) and this Values were higher than that of in Shahab bus drivers(75dB A).SIL values for Ikaroos bus drivers were higher than other that of other bus drivers. Results obtained of Frequency Analysis showed that age of buses in mid frequencies ws a meaningful on noise increase."nConclusion: Results showed that type and age of buses were effective factors in drivers. noise exposure levels (LEX, 8h), which was consistent with previous studies in this field.
The Study of the Status of Electromagnetic Waves Resulting from BTS (Base Transceiver Station), 900 Megahertz Frequency in Tehran
P Nasiri,M.R Monazam,S Zare,K Azam
Iranian Journal of Health and Environment , 2011,
Abstract: Background and Objectives: with the developments of technology, contact with various frequencies of electromagnetic fields ( EMF ) has significantly increased, while the abundant benefits of using microwaves in routine life cannot be neglected. During recent years there have been reports of adverse effects caused by contact with electric and magnetic fields of these waves that spread from BTS antennas. The purpose of this study is the measurement of microwaves spreading around BTS antennas in Tehran.Materials and Methods: according to the location of BTS antennas in Tehran , power density of electromagnetic waves around 63 antennas in near and distant fields in different distances was measured. The measurements were performed using the standard method of IEEE Std C95.1 by Hi-4333 device .in order to analysis data we used spss 16 and descriptive and deductive statistical tests.Results: results of this study show that in the near field, with increase of distance from the foot of antenna , the average power density of electromagnetic waves increase in a way that in the distance of 10 meters from the antenna foot , the increase of average power density is hardly conceivable and from 10 to 15 meters distance is perfectly noticeable. But in the distant field, with increase of distance from 20 meters, the average power density of the electromagnetic waves decreases; and from 100 meter and further, the gradient of the diagram will get almost linear and the rate of power density reaches the base limit in a way that with the increase of distance there would be no significant decrease.Conclusion: All the measures of power density of electromagnetic waves caused by BTSs are about 0.06% of recommended measures of environmental standards and 0.0000013% of occupational standards. The results of this study are close to the results of other studies.
The Effect of Noise on Human Performance: A Clinical Trial
P Nassiri,M Monazam,B Fouladi Dehaghi,L Ibrahimi Ghavam Abadi
International Journal of Occupational and Environmental Medicine , 2013,
Abstract: Background: Noise is defined as unwanted or meaningless sound that apart from auditory adverse health effects may distract attention from cues that are important for task performance. Human performance is influenced by many job-related factors and workplace conditions including noise level. Objective: To study the effect of noise on human performance. Methods: The participants included 40 healthy male university students. The experimental design consisted of 3 (sound pressure level) x 3 (noise schedule) x 2 (noise type) factors. To investigate occupational skill performance, some specific test batteries were used: 1) steadiness test, 2) Minnesota manual dexterity test, 3) hand tool dexterity test, and 4) two-arm coordination test. Time duration of test completion was measured as speed response; to determine error response, the time taken during committing an error by participants while performing a task was measured. Results: Speed response obtained from the 4 tests in combined conditions of noise schedule, harmonic index, and sound pressure level was highest for (intermittent, treble, 95 dB), (continuous, treble, 95 dB), (continuous, treble, 85 dB) and (intermittent, treble, 95 dB), respectively. Conclusion: Treble noise was found significant in reducing human performance; also, intermittent noise, especially at high pressure levels, was responsible for worsening environmental conditions during performing a task.
Comparing the Heat Stress (DI, WBGT, SW) Indices and the Men Physiological Parameters in Hot and Humid Environment
Farideh Golbabaie,Mohammad Reza Monazam Esmaieli,Rasoul Hemmatjou,Parvin nasiri
Iranian Journal of Health and Environment , 2012,
Abstract: Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background and Objectives: Heat stress is considered as a serious threat to the health and safety of workers in many industries, including petrochemical and steel. Assessment of the heat stress is important from the disease prevention point of view and also for the safety and performance of workers at workplace. Although there are many indices to evaluate the heat stress, it is hard to select an applicable index for a wide range of weather conditions. The purpose of the study was to develop an optimal index based on physiological parameters in a petrochemical industry. Materials and Methods: The study was conducted in a petrochemical industry located in Assaluyeh (south of Iran). Twenty one healthy young men at different levels of fitness and heat acclimation volunteered to participate in the study. Physiological parameters including heart rate, systolic and diastolic blood pressure, skin temperature and oral temperature were measured during the working day over two consecutive weeks. Simultaneously, we measured the climatic parameters required to calculate the wet bulb globe temperature (WBGT), required sweat rate (SWreq), and the discomfort index (DI) indices. Results: All the measurements took place on 2 sites: Kar (working place) and Paziresh (resting room). Our results showed that the mean values of indices and physiological parameters in Kar for both acclimated and unacclimated groups were significantly higher than Paziresh (P<0.05). There was the strongest linear correlation between WBGT and heart rate (0.731), systolic blood pressure (0.695) and diastolic blood pressure (0.375) and skin temperature (0.451) respectively. The amounts of DI were 0.725, 0.446, 0.352, and 0.689 respectively. But the strongest linear relationship existed between SWreq and deep body temperature (0.766). Conclusion: There were significant differences in the present indices and physiological parameters of Kar and Paziresh, confirming the previous studies findings. Finally, WBGT was considered optimal index and the results revealed the almost perfect linear correlation between WBGT and heart rate. We propose WBGT can be the most applicable index for evaluating heat stress in this climate. st1":*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm
Quasi-particle band structures and optical properties of the "magic sequence" SiGe superstructure
Mohammad Reza Ahmadpour Monazam,Kurt Hingerl,Peter Puschnig
Physics , 2015, DOI: 10.1103/PhysRevB.88.075314
Abstract: The quasi-particle band structure and dielectric function for the so-called magic sequence SiGe$_2$Si$_2$Ge$_2$SiGe$_{12}$ (or $\alpha_{12}$) structure [PRL 108, 027401 (2012)] are calculated by many-body perturbation theory (MBPT) within an ab-initio framework. On top of density functional calculations within the local density approximation (LDA) leading to a fundamental band gap of 0.23 eV, we have computed the quasi-particle band structure within the G$_0$W$_0$ approach opening the gap to 0.61 eV. Moreover, we have calculated the optical properties by solving the Bethe-Salpeter equation (BSE) for the electron-hole two-particle correlation function. When comparing the imaginary part of the dielectric function obtained at various levels of approximation, \emph{i.e.} the independent particle approximation (or random phase approximation) based on (i) the LDA or (ii) GW band structures, and (iii) the BSE including local field effects and electron-hole correlations, we observe that the important first transition is better explained with taking into account excitonic effects. Moreover, the onset transition originating from the direct transition of the magic sequence structure is also investigated.
Study of Duct Characteristics Deduced from Low Latitude Ground Observations of Day-Time Whistler at Jammu  [PDF]
M. Altaf, M. M. Ahmad
International Journal of Astronomy and Astrophysics (IJAA) , 2013, DOI: 10.4236/ijaa.2013.33032
Abstract:

Propagation characteristics of low latitude whistler duct characteristics have been investigated based on day-time measurements at Jammu. The morphogical characteristics of low latitude whistlers are discussed and compared with characteristics of middle and high latitude whistlers. The Max. electron density (Nm) at the height of the ionosphere obtained from whistler dispersion comes out to be higher than that of the background which is in accordance with the characteristics of whistler duct. The equivalent width is found to be close to the satellite observations and the characteristics of whistler duct in low latitude ionosphere are similar to those in middle and high latitude ionosphere. The width of ducts estimated from the diffuseness of the whistler track observed during magnetic storm is found to lie in the range of 50 - 200 Km.

Review Article: Immobilized Molecules Using Biomaterials and Nanobiotechnology  [PDF]
Magdy M. M. Elnashar
Journal of Biomaterials and Nanobiotechnology (JBNB) , 2010, DOI: 10.4236/jbnb.2010.11008
Abstract: Immobilized molecules using biomaterials and nanobiotechnology is a very interesting topic that touching almost all aspects of our life. It uses the sciences of biology, chemistry, physics, materials engineering and computer science to develop instruments and products that are at the cutting edge of some of today’s most promising scientific frontiers. In this review article, the author based on his experience in this arena has tried to focus on some of the supports for im-mobilization; the most important molecules to be immobilized such as DNA, cells, enzymes, metals, polysaccharides, etc and their applications in medicine, food, drug, water treatment, energy and even in aerospace. He specified a special section on what is new in the arena of supports and technologies used in enzyme immobilization and finally a recommendation by the author for future work with a special attention to up-to-date references.
Using of the generalized special relativity (GSR) in estimating the neutrino masses to explain the conversion of electron neutrinos  [PDF]
M. H. M. Hilo
Natural Science (NS) , 2011, DOI: 10.4236/ns.2011.34044
Abstract: In this work the Generalized Special Relativity (GSR) is utilized to estimate masses of some elementary particles such as, neutrinos. These results are found to be in conformity with experimental and theoretical data. The results obtained may explain some physical phenomena, such as, conversion of neutrinos from type to type when solar neutrino reaches the Earth.
Postischemic Lower Extremity Wounds Treated with and without Negative Pressure Dressing  [PDF]
Naz？m Gümü？
Surgical Science (SS) , 2012, DOI: 10.4236/ss.2012.37075
Abstract: Background: Vacuum-assisted dressing is a noninvasive closure system of the wound, which makes localized and controlled negative pressure. Its mechanical tension reduces edema, stimulates granulation tissue formation and angiogenesis, and prepares the wound bed for closure. In this study, a patient has been presented, who suffered from serious lower extremity wounds due to arterial emboli, one of her wounds has been treated with vacuum-assisted dressing and the other with conventional dressing to evaluate the efficacy of vacuum-assisted dressing in acute ischemic wounds. Methods: A 65-year-old female patient was admitted to the emergency clinic, due to complaint of severe pain in her right lower extremity which suggested an acute arterial occlusion. She immediately underwent an embolectomy operation; however, a few days later, severe ischemia on the leg and foot became appearant. All of the necrosis was sharply debrided under sterile conditions in the operating room, and then lower leg wound was covered with vacuum-assisted dressing, also calcaneal wound was dressed with silver sulphadiazine. Results: Eighteen days after the first dressing with negative pressure, distal leg wound became ready for closure, whereas, enough granulation tissue over the calcaneal area developed merely thirty-four days later. Calcaneal wound closed spontaneously within fifty-three days. Conclusions: When dealing with this experience, using the negative pressure dressing in patient with severe lower limb wounds following arterial emboli, accelerates wound healing by means of developing the granulation tissue, and rapidly prepares the wound for closure, so it may reduce the risk of amputation.
Laplace Transform Method for Unsteady Thin Film Flow of a Second Grade Fluid through a Porous Medium  [PDF]
M. Ali, M. Awais
Journal of Modern Physics (JMP) , 2014, DOI: 10.4236/jmp.2014.53017
Abstract:

In this article, we have effectively used the Numerical Inversion of Laplace transform to study the time-dependent thin film flow of a second grade fluid flowing down an inclined plane through a porous medium. The solution to the governing equation is obtained by using the standard Laplace transform. However, to transform the obtained solutions from Laplace space back to the original space, we have used the Numerical Inversion of Laplace transform. Graphical results have been presented to show the effects of different parameters involved and to show how the fluid flow evolves with time.

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