STURCUTURE INDUCED MODIFICATION IN THE FERROELECTRIC AND CURRENT CONDUTION BEHAVIOUR OF PZT THIN FILMS

Ramezani daevish, S.,Rastogi, A.C.,Bhatnagar, P.K. 한국재료학회 1995 Fabrication and Characterization of Advanced Mater Vol.2 No.e3

Crystalline structure induced effecs on the ferroelectric and current conduction properties in electron beam deposited PZT thin films are described. $TiO_2$ dispersion in PZT reduces dielectric constant and charge storage density to 270 and $3.5\;{\mu}C/cm^2$ and increases carrier density. Pyrochlore PZT inclusion cause further reduction to 60 and $77fC/cm^2$ but have no effect on the microscpic polarization. Activated conduction energy 0.25-0.3eV is observed in $TiO_2$ mixed PZT. Low field conduction is ohmic and changes to space charge limited at a threshold field $8{\times}10^4\;V/cm$. Inclusion of pyrochlore phase causes deep traps ${\thickapprox}5{\times}10^18cm^-3$ and increased hole density of ${\thickapprox}\;3{\times}10^11\;cm^-3$.

Effect of temperature on development time and life table parameters of Nephus hiekei Fürsch, the important predator of Phenacoccus solenopsis Tinsley

Ramezani Leila,Torfi Ebrahim Tamoli,Zarghami Sara,Rezai Nastaran 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.2

The cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) has become a serious threat to agricultural and ornamental plants in Southwest Iran. Pest-control studies have found Nephus hiekei Fürsch (Coleoptera: Coccinellidae), in large numbers on Phenacoccus solenopsis Tinsley, as a potential predator. How ever, there has been no investigation on this predator. In this research, the biology and age-stage, two-sex life table parameters of N. hiekei feeding on Ph. solenopsis were investigated at three constant temperatures (27, 32 and 37 ± 1 ◦ C, 65 ± 5% RH and a photoperiod of 16: 8 (L: D) h. The duration of total pre-adult stage was found to decrease raising temperature from 26.98 ± 0.36 days at 27 ◦ C to 14.24 ± 0.27 days at 37 ◦ C. The oviposition period lasted 63.95 ± 3.14, 66.42 ± 3.34 and 25.20 ± 1.59 days at 27, 32, and 37 ◦ C, respectively. Females laid an average of 365.68 ± 22.36, 543.79 ± 27.27 and 106.25 ± 6.38 eggs, at these three temperatures, respectively. The intrinsic rate of increase (r m = 0.1333 ± 0.0050 d –1 ), finite rate of increase (λ = 1.1423 ± 0.0057 d –1 ) and net reproductive rate (R 0 = 188.89 ± 28.34 offspring) as well as gross reproductive rate (GRR = 308.31 ± 39.54 offspring) were greatest at 32 ◦ C. The shortest mean generation time (T = 26.74 ± 0.65 days) was recorded at 37 ◦ C and the longest at 27 ◦ C (T = 56.48 ± 1.0 days). These results indicate that N. hiekei can successfully survive and reproduce at temperatures of around 32 ◦ C, and has good potential to be an effective biological control agent of Ph. solenopsis.

Optimizing airport service performance by spatial multi objective location allocation problem

Ramezani Abouzar,Malek Mohammad Reza,Mohammadi Nazila 대한공간정보학회 2021 Spatial Information Research Vol.29 No.3

The increase in world population and the value of time in the current period are changing the importance of air transportation. Due to increase popularity, airport officials have increased the number of flights. Because of the fact that the airports capacity is constant, airport traffic has increased. Regarding this, airport managers are looking for a solution to reduce traffic at airports and optimize the performance of service cars at the airport. The most important innovation of this research is developing a model for dynamic location of Equipment Parking Area (EPA) with optimal allocation of airport services in two different service modes. The goal of model is reducing costs and traffic and optimizing available spaces. To find optimal solution, two objective functions have been developed in the form of median and cover problems, and EPA locations have been located in a way that minimize the objective functions. The purpose of these functions are minimizing traffic at the airport and minimizing delays in flights. Using the developed model, EPA locations can be located for different time period flights and can be used to optimize the operations of the service cars without delay. The proposed model has been implemented for the Imam Khomeini International Airport and the results indicate that the number of service cars for nine flights has been decreased about 30% without any delay, as well as the amount of traffic have been decreased about 1300 meters in the first case and in 500 m in the second one.

P16^INK4a Immunostaining but Lack of Human Papilloma Virus Type 16 in Cutaneous Squamous Cell Carcinoma and Basal Cell Carcinoma: a Report from West Iran

Ramezani, Mazaher,Abdali, Elham,Khazaei, Sedigheh,Vaisi-Raygani, Asad,Sadeghi, Masoud Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.3

The tumor suppressor p16 is a biomarker for transforming human papilloma virus (HPV) infections that can lead to contradictory results in skin carcinomas. The aim of this study was to evaluate p16 expression and HPV-16 infection in the cutaneous basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). This case-control study was performed on paraffin blocks of BCCs and SCCs and normal skin (53, 36, and 44 cases, respectively), between 2006 to 2015. Initial sections for groups were stained with hematoxylin and eosin (H & E). Immunohistochemistry was performed for p16 expression and human papilloma virus type 16 (HPV-16) infection. Normal group was skin of mammoplasty specimens and normal skin tissue in the periphery of tumors. The mean age at diagnosis was 42.1, 61.7 and 71.4 years for normal, BCC and SCC groups, respectively. P16 positivity was more in SCC and BCC groups compared to normal group (P<0.05) and HPV was negative in all patients in three groups. Also, the mean age at diagnosis and P16-positivity were higher for the SCC group than the BCC group (P<0.005). In conclusion, in non-melanoma skin cancers (SCC and BCC), p16-positivity can be a prognostic factor but there is no correlation between HPV-16 and p16 in these tumors.

A New Zero-Voltage-Switching Bridgeless PFC, Using an Active Clamp

Ramezani, Mehdi,Ghasedian, Ehsan,Madani, Seyed M. The Korean Institute of Power Electronics 2012 JOURNAL OF POWER ELECTRONICS Vol.12 No.5

This paper presents a new ZVS single phase bridgeless (Power Factor Correction) PFC, using an active clamp to achieve zero-voltage-switching for all main switches and diodes. Since the presented PFC uses a bridgeless rectifier, most of the time, only two semiconductor components are in the main current path, instead of three in conventional single-switch configurations. This property significantly reduces the conduction losses,. Moreover, zero voltage switching removes switching loss of all main switches and diodes. Also, auxiliary switch turns on zero current condition. The presented converter needs just a simple non-isolated gate drive circuitry to drive all switches. The eight stages of each switching period and the design considerations and a control strategy are explained. Finally, the converter operation is verified by simulation and experimental results.

The Impact of Knowledge-Oriented Leadership on Innovative Performance through Considering the Mediating Role of Knowledge Management Practices

Ramezani, Yousef,Safari, Zehed,Hashemiamin, Arezoosadat,Karimi, Zahra Korean Institute of Industrial Engineers 2017 Industrial Engineeering & Management Systems Vol.16 No.4

Strategists consider knowledge as a basic asset source through passing from source-oriented to knowledge-oriented approach in organizations, and the value of knowledge is evaluated based on how that knowledge is used in organization process, in order to produce goods and services. The purpose of this the study is to evaluate the impacts of aspects of knowledge-oriented leadership on innovative performance through considering mediating role of knowledge management practices in head quarter's domain of energy consultant engineering of Khorasan. The methodology of this research is descriptive study. Also, the purpose of the study is an applied research. The study population consisted of all employees in head quarter's domain of energy consultant engineering of Khorasan that includes 200 people. According to Morgan table, the sample size is 130 people that the questioners were randomly distributed among them. The questioner was used for data collection, and LISREL software was used for data analysis. The results of the study proved the impacts of aspects of knowledge-oriented leadership on innovative performance through considering mediating role of knowledge management practices in headquarters' domain of energy consultant. In this context, the present study hypothesis was confirmed.

Economic Growth and Food Imports : Evidence from Saudi Arabia

Ramezani, Cyrus A. 세종대학교 국제경제연구소 1995 Journal of Economic Integration Vol.10 No.3

Saudi Arabia has experienced rapid economic growth since the 1960s. The sustained income growth, supported primarily by oil revenues, has brought about affluent nations in the global market place. This study examines the impact of economic growth on consumption patterns and food imports. The Almost Ideal Demand System is used to study the patterns of substitution and complementarity in consumption. Monte Carlo sampling is used to generate confidence intervals for the estimated elasticities and conduct policy simulation. The analysis indicates that economic growth combined with food subsidies have resulted in a shift in consumption away from grains (the traditional diet) to meats and dairy products. This rise in demand is driven by high income elasticities for luxury food items and is further fueled by the income effect of subsidized grain prices. The study provides evidence that well-intentioned policies that distort relative prices lead to undesirable outcomes in terms of increasing demand for food imports and induce shifts in consumption, both with important long run economic implications.

Comparison of EMA,CEA, CD10 and Bcl-2 Biomarkers by Immunohistochemistry in Squamous Cell Carcinoma and Basal Cell Carcinoma of the Skin

Ramezani, Mazaher,Mohamadzaheri, Elham,Khazaei, Sedigheh,Najafi, Farid,Vaisi-Raygani, Asad,Rahbar, Mahtab,Sadeghi, Masoud Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.3

Background: Basal and squamous cell carcinoma (BCC and SCC) are the most common skin cancers worldwide and distinction between the two may sometimes be very difficult in routine histopathology. The present study was aimed to evaluate a reliable diagnostic method for these cancers based on immunohistochemistry (IHC). Materials and Methods: IHC was used with antibodies to Bcl-2, CD10, CEA, and EMA biomarkers, which despite non-specificity are easily available for detection of various types of tumors in pathology sections and can be used as a panel for differentiation. In this descriptive and analytic study, paraffin-embedded blocks of 29 SCC patients and 29 BCC patients were collected and sectioned for IHC staining. The results were analyzed by the STATA (version 8) statistical package using the Chi-square test. Results: BCC patients were 100%, 75.8%, 0% and 0% positive for Bcl-2, CD10, CEA and EMA markers, respectively, and for SCC patients were 3.5%, 0%, 34.5% and 82.7% positive, respectively. Using simultaneously Bcl-2 and CD10 as positive markers, detection of BCC with 88% accuracy and 100% specificity was possible, while application of CEA and EMA positivity could detect SCC with 67% accuracy and 100% specificity. Conclusions: SCC and BCC have different immunostaining profiles; therefore, Bcl-2, CD10, CEA and EMA markers can be helpful to distinguish between them.

CpG Island Methylation Profile of Estrogen Receptor Alpha in Iranian Females with Triple Negative or Non-triple Negative Breast Cancer: New Marker of Poor Prognosis

Ramezani, Fatemeh,Salami, Siamak,Omrani, Mir Davood,Maleki, Davood Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.2

One decade early onset of the breast cancer in Iranian females was reported but the basis of the observed difference has remained unclear and difference in gene silencing by epigenetic processes is suggested. Hence, this study was sought to map the methylation status of estrogen receptor (ER) gene CpG islands and its impact on clinicopathological factors of triple negative and non-triple negative ductal cell carcinoma of the breast in Iranian females. Surgically resected formalin-fixed paraffin-embedded breast tissues from sixty Iranian women with confirmed invasive ductal carcinoma were assessed by methylation-specific PCR using primer sets encompassing some of the 29 CpGs across the ER gene CpG island. The estrogen and progesterone receptors, Her-$2^+$ overexpression, and nuclear accumulation of P53 were examined using immunohistochemistry (IHC). Methylated ER3, ER4, and ER5 were found in 41.7, 11.3, and 43.3% of the samples, respectively. Significantly higher methylation of ER4 was found in the tumors with nuclear accumulation of P53, and significantly higher methylation of ER5 was found in patients with lymph node involvement and tumor with bigger size or higher grades. Furthermore, significantly higher rate of ER5 methylation was found in patients with Her-$2^+$ tumors and in postmenopausal patients with $ER^-$, $PgR^-$, or $ER^-/PgR^-$ tumors. However, no significant difference in ERs methylation status was found between triple negative and non-triple negative tumors in pre- and postmenopausal patients. Findings revealed that aberrant hypermethylation of the ER-alpha gene frequently occurs in Iranian women with invasive ductal cell carcinoma of the breast. However, methylation of different CpG islands produced a diverse impact on the prognosis of breast cancer, and ER5 was found to be the most frequently methylated region in the Iranian women, and could serve as a marker of poor prognosis.

Likelihood-Based Modulation Classification for Multiple-Antenna Receiver

Ramezani-Kebrya, Ali,Il-Min Kim,Dong In Kim,Chan, Francois,Inkol, Robert IEEE 2013 IEEE TRANSACTIONS ON COMMUNICATIONS Vol.61 No.9

<P>Likelihood-based algorithms for the classification of linear digital modulations are systematically investigated for a multiple receive antennas configuration. Existing modulation classification (MC) algorithms are first extended to the case of multiple receive antennas and then a critical problem is identified that the overall performance of the multiple antenna systems is dominated by the worst channel estimate of a particular antenna. To address the performance degradation issue, we propose a new MC algorithm by optimally combining the log likelihood functions (LLFs). Furthermore, to analyze the upper-bound performance of the existing and the proposed MC algorithms, the exact Cramer-Rao Lower Bound (CRLB) expressions of non-data-aided joint estimates of amplitude, phase, and noise variance are derived for general rectangular quadrature amplitude modulation (QAM). Numerical results demonstrate the accuracy of the CRLB expressions and verify that the results reported in the literature for quadrature phase-shift keying (QPSK) and 16-QAM are special cases of our derived expressions. Also, it is demonstrated that the probability of correct classification of the new algorithm approaches the theoretical bounds and a substantial performance improvement is achieved compared to the existing MC algorithm.</P>