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        Theory, Design, and Implementation of a New Family of Ultra-Wideband Metamaterial Microstrip Array Antennas Based on Fractal and Fibonacci Geometric Patterns

        Besharat Rezaei Shookooh,Alireza Monajati,Hamid Khodabakhshi 한국전자파학회JEES 2020 Journal of Electromagnetic Engineering and Science Vol.20 No.1

        The theory and design of a new family of ultra-wideband (UWB) metamaterial (MTM) microstrip array antennas based on fractal and Fibonacci geometric patterns are investigated. First, the UWB microstrip array antenna is presented with two radiating MTM elements. Then, using fractal and Fibonacci geometric patterns, the array antenna is expanded. Improvements in the antenna parameters is achieved by repeating the second and third iterations of the fractal and Fibonacci patterns. As the order of iteration of the fractal and Fibonacci geometric patterns increases, the impedance bandwidth of the MTM microstrip array antenna increases, and its radar cross-section (RCS) decreases. The impedance bandwidth of the array antenna with two MTM elements is 3.37–9.2 GHz, while the bandwidth of the third-iteration Fibonacci and fractal MTM array antennas are 3.5–10.1 GHz and 3.55–10.34 GHz, respectively. Furthermore, the proposed array antennas exhibit lower RCS due to metal area reduction, with respect to the array antenna with two MTM elements.

      • Diagnostic Values of Serum Levels of Pepsinogens and Gastrin-17 for Screening Gastritis and Gastric Cancer in a High Risk Area in Northern Iran

        Nejadi-Kelarijani, Fatemeh,Roshandel, Gholamreza,Semnani, Shahryar,Ahmadi, Ali,Faghani, Behzad,Besharat, Sima,Akhavan-Tabib, Atefeh,Amiriani, Taghi Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.17

        Background: Gastric cancer (GC) is the second cause of cancer related death in the world. It may develop by progression from its precancerous condition, called gastric atrophy (GA) due to gastritis. The aim of this study was to evaluate the accuracy of serum levels of pepsinogens (Pg) and gastrin-17 (G17) as non-invasive methods to discriminate GA or GC (GA/GC) patients. Materials and Methods: Subjects referred to gastrointestinal clinics of Golestan province of Iran during 2010 and 2011 were invited to participate. Serum levels of PgI, PgII and G17 were measured using a GastroPanel kit. Based on the pathological examination of endoscopic biopsy samples, subjects were classified into four groups: normal, non-atrophic gastritis, GA, and GC. Receiver operating curve (ROC) analysis was used to determine cut-off values. Indices of validity were calculated for serum markers. Results: Study groups were normal individuals (n=74), non-atrophic gastritis (n=90), GA (n=31) and GC patients (n=30). The best cut-off points for PgI, PgI/II ratio, G17 and HP were $80{\mu}g/L$, 10, 6 pmol/L, and 20 EIU, respectively. PgI could differentiate GA/GC with high accuracy (AUC=0.83; 95%CI: 0.76-0.89). The accuracy of a combination of PgI and PgI/II ratio for detecting GA/GC was also relatively high (AUC=0.78; 95%CI: 0.70-0.86). Conclusions: Our findings suggested PgI alone as well as a combination of PgI and PgI/II ratio are valid markers to differentiate GA/GC. Therefore, Pgs may be considered in conducting GC screening programs in high-risk areas.

      • Epidemiological Pattern of Breast Cancer in Iranian Women: Is there an Ethnic Disparity?

        Taheri, Neger Sadat,Nosrat, Sepideh Bakhshandeh,Aarabi, Mohsen,Tabiei, Mohammad Naeimi,Kashani, Elham,Rajaei, Siamak,Besharat, Sima,Semnani, Shahryar,Roshandel, Gholamreza Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.9

        Introduction: Northeastern Iran is known as a high risk area of upper gastrointestinal cancers. Recent reports have suggested a declining trend for these cancers as well as an increase in the incidence of other malignancies including breast cancer. Our present aim was to describe the epidemiological pattern of breast cancer in this region during 2004-2009. Methods: All new cancer cases from public and private diagnostic and therapeutic centers of Golestan province were registered. A structured questionnaire was prepared and used based on the standerds of the International Association of Cancer Registries. The international classification of diseases for oncology was considered for coding. Age standardized incidence rates (ASR) of breast cancer were calculated. Results: A total of 11,038 new cancer cases were registered during 2004-2009, of which, 1,101 (10%) were females with breast cancer. The median age of the breast cancer patients was 46 years. The ASR for breast cancer was 28 per 100,000 person-years. We found an unusual rapid increase in breast cancer rate at the age of 25 years. The ASR of breast cancer was significantly lower in females from Turkmen ethnicity and those from rural areas(P value <0.01). Conclusion: Our study showed high rate of breast cancer in Golestan province of Iran. We found an unusual peak of breast cancer in young women. So, the age of starting screening programs may need to be revised in this area. The rate of breast cancer was significantly lower in women from Turkmen ethnicity. Further studies are warranted to clarify the role of important determinants, especially regarding the ethnic disparity, on breast cancer in this region.

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