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AbstractClosed-loop control of the reactor-follow-turbine operation is attempted in this work. The reactor power is intended to follow the turbine load demand, whereas the coolant average temperature is to be maintained constant for reasons of design safety. To this effect, a standardized pressurized water reactor model is adopted wherein the reactor external reactivity and the feedwater mass flux are deemed the manipulated control signals. Offline system identification is carried out on the model input/output (I/O) terminals to extract first order plus time delay models thereof. A further relative gain array analysis is conducted to determine the most tightly coupled I/O channels. A proportional integral controller is thereafter designed for each channel, making use of an analytical gain/phase margin tuning mechanism. The results for different output tracking scenarios confirm a feasible and quite satisfactory closed-loop control practice. [ABSTRACT FROM AUTHOR]

Mohammad Zarei,1 Ramak Roohipoor,1 Raziyeh Mahmoudzadeh,1 Mehdi Yaseri,2 Hamid Riazi-Esfahani1 1Retina Service, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran; 2Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, IranCorrespondence: Hamid Riazi-EsfahaniRetina Service, Farabi Eye Hospital, Tehran University of Medical Sciences, Qazvin Square, South Kargar Street, Tehran 1336616351, IranTel +98 9123779108Email Hamidriazi@gmail.comPurpose: To study the relative contribution of major indications and geographic referral patterns for intravitreal bevacizumab injections in a tertiary hospital.Methods: In this retrospective study, hospital electronic registry was used to categorize patients who had received intravitreal injections (IVIs) during the 2014– 2016 period into different groups based on indications. Relative contribution of each indication and odds of being resident of provinces other than Tehran were determined.Results: The most prevalent indications for IVI were pathologies related to diabetes mellitus (DM) followed by choroidal neovascularization (CNV)/age-related macular degeneration (AMD) and retinal venous occlusion (RVO)-related complications. From 38,043 patients, 61.8% were residents of Tehran province. Patients in the CNV/AMD group were the oldest. Patients from Tehran province were significantly older (62.44 ± 11.42 (12– 99)) than patients who were referred from other provinces (59.23 ± 11.39 (11– 102)) (p=< 0.001). The majority of patients in all indication categories were from Tehran province, except for patients with retinopathy of prematurity (ROP). Odds of being referred from outside Tehran province for the ROP group compared to the DM-related, CNV/AMD, RVO-related and miscellaneous groups were 3.32, 4.27, 3.13 and 2.83, respectively (p< 0.001).Conclusion: DM-related ocular complications outnumber all other indications of IVIs combined. Considering the preventable nature of these complications, efficient health policies can significantly reduce the burden of IVIs in Iran. The contribution of each indication category in overall burden of IVIs seems to vary considerably between different countries which merits further studies. The disproportionately high ratio of ROP patients who are referred from other provinces to the capital province for treatment indicates a suboptimal distribution of ROP care services throughout the country.Keywords: epidemiology, indications, intravitreal injection, diabetes, retinopathy of prematurity, referral patterns

Mahdi Rahimi,1 Ramin Karimian,2 Ehsan Bahojb Noruzi,3 Khudaverdi Ganbarov,4 Mojtaba Zarei,1 Fadhil S Kamounah,5 Bahman Yousefi,1 Milad Bastami,6 Mehdi Yousefi,7 Hossein Samadi Kafil1 1Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran; 2Chemical Injuries Research Center, Systems biology and poisonings institute, Baqiyatallah University of Medical Sciences, Tehran, Iran; 3Faculty of Chemistry, Department of Inorganic Chemistry, University of Tabriz, Tabriz, Iran; 4Department of Microbiology, Baku State University, Baku, Republic of Azerbaijan; 5Department of Chemistry, University of Copenhagen, Copenhagen. Denmark; 6Biotechnology Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran; 7Stem Cell Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran Background: Chemotherapy as an important tool for cancer treatment faces many obstacles such as multidrug resistance and adverse toxic effects on healthy tissues. Drug delivery systems has opened a new window to overcome these problems. There has been a strong interest development of new platform and system for delivof chemotherapeutic agents. Purpose: In the present study, a green synthesis method was chosen and performed for preparation of a novel amphoteric calix[4]arene (Calix) macrocycle with low toxicity to the human body. Materials and methods: The amphoteric Calix was coated on the surface of Fe3O4 magnetic nanoparticles and used as a magnetic nanocarrier for simultaneous delivery of two anticancer agents, doxorubicin and methotrexate, against MCF7 cancer cells. Several chemical characterizations were done for validation of prepared nanocarrier, and in vitro loading and release studies of drugs were performed with good encapsulation efficiency. Results: In vitro biological studies including hemolysis assay, erythrocytes sedimentation rate, red blood cells aggregation, cyto cellular internalization, and apoptosis evaluations were performed. Based on results, the developed nanocarrier has many advantages and capability for an efficient codelivery of DOX and MTX, which has a highly potent ability to kill cancer cells. Conclusion: All these results persuade us, this nanocarrier could be effectively used for cancer therapy of MCF7 breast cancer cells and is suitable for use in further animal studies in future investigations. Keywords: green synthesis, amphoteric calix[4]arene, drug delivery, combination therapy, MCF7 cells

Weather conditions such as rainfall and freeze-thaw cycles affect the pavement performance of airports; therefore, methods such as using de-icing chemicals are considered to maintain the normal condition of the airport runway. In addition to the above factors, de-icing chemicals play an important role in pavement performance and the damage caused to it due to their chemical nature. Therefore, investigating the effect of deicing chemicals and determining the appropriate material to maintain the airport's pavement is a priority for engineers. In this study, the effect of three de-icing chemicals, sodium chloride, potassium acetate, and ethylene glycol (at concentrations of 23.3%, 49%, and 69.07%, respectively) on skid resistance (The British Pendulum Test (BPT) and The Road Test Machine (RTM)) and the mechanical properties (Compressive Strength Test) of the concrete under Freezing and Thawing Cycle were investigated. The BPT test results showed that sodium chloride resulted in better skid resistance than other chemicals when the number of cycles is more than 100 cycles. This result was also obtained for all cycles in the RTM test. Also, ethylene glycol was not suitable for improving skid resistance based on BPT and RTM tests. Furthermore, the results of the compressive strength of concrete mixtures showed that the de-icing chemicals reduced the compressive strength of concrete mixtures. Based on all the results, sodium chloride had better results than other chemicals. [ABSTRACT FROM AUTHOR]

Background: Radiation therapy is among the most conventional cancer therapeutic modalities with effective local tumor control. However, due to the development of radio-resistance, tumor recurrence and metastasis often occur following radiation therapy. In recent years, combination of radiotherapy and gene therapy has been suggested to overcome this problem. The aim of the current study was to explore the potential synergistic effects of N-Myc Downstream-Regulated Gene 2 (NDRG2) overexpression, a newly identified candidate tumor suppressor gene, with radiotherapy against proliferation of prostate LNCaP cell line. Materials and Methods: In this study, LNCaP cells were exposed to X-ray radiation in the presence or absence of NDRG2 overexpression using plasmid PSES- pAdenoVator-PSA-NDRG2-IRES-GFP. The effects of NDRG2 overexpression, X-ray radiation or combination of both on the cell proliferation and apoptosis of LNCaP cells were then analyzed using MTT assay and flow cytometery, respectively. Results: Results of MTT assay showed that NDRG2 overexpression and X-ray radiation had a synergistic effect against proliferation of LNCaP cells. Moreover, NDRG2 overexpression increased apoptotic effect of X-ray radiation in LNCaP cells synergistically. Conclusion: Our findings suggested that NDRG2 overexpression in combination with radiotherapy may be an effective therapeutic option against prostate cancer.

This study evaluated the mechanical properties and abrasion resistance of the concrete pavement when cement was replaced by the blast furnace slag (BFS) and Gilsonite at levels of 20%, 25%, and 30%, as well as 5%, 7%, and 9%, respectively. For this purpose, a total of ten mixing designs were made and cured for 28 days. The results showed that the compressive strength of mixtures containing two additives decreased. In contrast, the BFS20-G7 (i.e., sample containing 20% BFS and 7% Gilsonite) mixture satisfied the proposed minimum compressive strength. However, the flexural strength and tensile splitting of the BFS20-G7 containing 20% BFS and 7% Gilsonite increased by about 4 and 7 percent. The Wide Wheel Abrasion Test results showed that the mixture containing 20% BFS-7% Gilsonite increased the abrasion resistance by about 5% and 17% in 100 and 300 revolutions, respectively. Conclusively, using BFS20-G7 in low traffic areas such as park and driveway can be suggested. [ABSTRACT FROM AUTHOR]