Improved Diagnostic Accuracy in Characterization of Adnexal Masses by Detection of Choline Peak Using 1H MR Spectroscopy in Comparison to Internal Reference at 3 Tesla

Malek, Mahrooz,Pourashraf, Maryam,Gilani, Mitra Modares,Gity, Masoumeh Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.12

Background: The aim of this study was to assess the role of the presence of a choline peak in 3 Tesla 1H magnetic resonance spectroscopy (MRS) for differentiating benign from malignant adnexal masses. Materials and Methods: A total of 46 adnexal masses (23 malignant and 23 benign) underwent 1H MRS study prior to surgery to assess the presence of choline peak. Results: A choline peak was detected in 16 malignant masses (69.5%) and was absent in the other 7 (30.5%). A choline peak was only detected in 6 (26%) of the benign adnexal masses. The presence of an MRS choline peak had a sensitivity of 69.5%, a specificity of 74%, a positive predictive value (PPV) of 72.7%, and a negative predictive value (NPV) of 71% for diagnosing malignant adnexal masses. A significant difference between the frequency of mean choline peaks in benign and malignant adnexal masses was observed (P value < 0.01). Conclusions: A 1H MRS choline peak is seen in malignant adnexal masses more frequently than the benign masses, and may be helpful for diagnosing malignant adnexal masses.

Climate effect on tree-ring widths of Fagus orientalis in the Caspian forests, northern Iran

Malek Haghshenas,Mohammad Reza Marvi Mohadjer,Pedram Attarod,Kambiz Pourtahmasi,Jeff Feldhaus,Seyed Mohammad Moein Sadeghi 한국산림과학회 2016 Forest Science And Technology Vol.12 No.4

This study aims at understanding the impacts of climate factors on the annual growth variations of oriental beech (Fagus orientalis Lipsky) at the Kheyrud Forest Research Station located in the Caspian forests of northern Iran. To this end, 18 disc samples were randomly taken from altitudes of 1038 to 1152 m above sea level. Tree rings were measured using TSAP-win software and a LINTABII machine. Since false and missing rings are typical in beech trees, skeleton plots were created to enhance crossdating accuracy. Chronologies were observed for a total of 15 samples. Meteorological data for rainfall and air temperature were recorded at the Nowshahr Meteorological Station, located near the study sites. Results showed a significant correlation between mean annual air temperature and radial growth (R D 0.54). Within the growing season, August temperatures reveal a significant correlation with tree ring (R D 0.41) while the highest association was observed in the previous December (R D 0.44) and the least association was found in February (R D 0.31). Excluding March (R D 0.33), there appeared to be no significant correlation between precipitation accumulated during and prior to the growing season and tree ring. In addition to oriental beech, there are many other species important to this region that may be sensitive to increasing temperatures.

Synthesis and characterization of Al-SiO2 composites

Malek Ali,Abderraouf Gherissi 한양대학교 세라믹연구소 2019 Journal of Ceramic Processing Research Vol.20 No.3

In this paper, aluminum matrix composites are successfully synthesized by melting of Al scrap at 850 oC. The reinforcementswere then added gradually for 10 minutes to the molten aluminum with different amounts weight ratios (10, and 20) wt.%of SiO2. Mixtures were stirred with 450 rpm for 10 minutes after the additions of SiO2. The mixture was poured into previouslyprepared sand mold. The uniaxial tensile, cupping, and biaxial tensile tests were conducted by Gant Universal test machine, andlocal designed biaxial tensile machine. Al-SiO2 composites presented good resistance to both uniaxial and biaxial tensile tests. It was observed that the ultimate tensile strength for Al- SiO2 composites with 0, 10, and 20 wt% of SiO2 were 25 MPa, 62 MPa,and 65 MPa and respectively. The Al- 20 % wt of SiO2 composite presents good resistance to biaxial tensile test, and both ofcomposites present a lower deformation ratio. The cupping results were promising for the composite with a ratio of 10 % wtit was deformed without failure until the depth d = 1.8 mm, whereas many cracks have been observed with 20 %wt of SiO2 atsmall forming depth. Experimental and a finite-element simulation for biaxial and cupping test gave very closed results.

Single particle mineralogy of microparticles from Himalayan ice-cores using SEM/EDX and ATR-FTIR imaging techniques for identification of volcanic ash signatures

Malek, Md Abdul,Eom, Hyo-Jin,Hwang, Heejin,Hur, Soon Do,Hong, Sungmin,Hou, Shugui,Ro, Chul-Un Elsevier 2019 Chemical geology Vol.504 No.-

<P><B>Abstract</B></P> <P>In this study, insoluble microparticles from four discrete layers of ice-cores drilled out from the East Rongbuk glacier of the Himalayas were characterized on a single particle basis by scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM/EDX) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) imaging. The combined application of the two single particle analytical techniques for the analysis of the same individual particles provided complementary information, i.e., their elemental compositions and morphology by SEM/EDX and their molecular species, functional groups, and crystallinity by ATR-FTIR imaging, which is crucial for the definite identification of the mineral species including their polymorphs. The results showed that the integrated signatures of volcanic ash (VA), involving their mineralogical characteristics for silica polymorphs, vitreous nature of silica and silicate particles, chemical heterogeneity within the micrometer sized particles, and unique morphology, can be used to clearly differentiate micrometer sized VA from the mineral dust of a soil origin on a single-particle basis. The different mineralogical characteristics among the volcanic samples would be due to their association with different volcanic eruptions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Single particle mineralogy of microparticles from ice-cores </LI> <LI> Combined use of SEM/EDX and ATR-FTIR imaging for analysis of the same single particles </LI> <LI> Integrated volcanic ash signatures observed for cryptotephra ice-core samples </LI> <LI> Diverse silica polymorph and vitreous silica contents for ice-core samples </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

FAR INFRARED GALAXIES IN AKARI'S EYE

Malek, K.,Pollo, A.,Takeuchi, T.T.,Giovannoli, E.,Buat, V.,Burgarella, D.,Malkan, M. The Korean Astronomical Society 2012 天文學論叢 Vol.27 No.4

We present the results of Spectral Energy Distribution (SED) fitting of far-infrared galaxies detected in the AKARI Deep Field-South (ADF-S) Survey and discuss their physical properties. Additionally, we perform a comparison between photometric redshifts estimated using only optical and both optical and infrared data. We conclude that our sample consists mostly of nearby galaxies rich in dust and young stars. We observe an improvement in the estimation of photometric redshifts when the IR data are included, comparing to a standard approach based mainly on the optical to UV photometry.

Relationship between the Interaction of Bending Stiffness of Component Yarns and the Structure of Fancy Bouclé and Semibouclé Yarns

Malek Alshukur,Alex Fotheringham,Hugh R. Gong 한국섬유공학회 2020 Fibers and polymers Vol.21 No.2

This article investigates how the bending stiffness of the core thread and the effect threads affect the average values and the variability of the structural properties of resultant fancy yarns. The Design of Experiment technique was used to study the effects of individual factors and the interactions of factors. The analysis indicated that that the bending stiffness of the effect thread was a main factor. Increases in the effect thread bending stiffness led to significant increases of the size of fancy profile and reductions of the number of fancy profiles. Additionally, there was a strong interaction effect between the bending stiffness of the core thread and the bending stiffness of the effect thread which influenced the structures of the resultant fancy yarns. It was also found that variations in the bending stiffness of the input threads were reflected in similarvariations in the size and number of fancy profiles. The study is important for engineering the structure and the variation in structural properties of fancy yarns by selecting appropriate input threads.

Differentiation of Benign from Malignant Adnexal Masses by Functional 3 Tesla MRI Techniques: Diffusion-Weighted Imaging and Time-Intensity Curves of Dynamic Contrast-Enhanced MRI

Malek, Mahrooz,Pourashraf, Maryam,Mousavi, Azam Sadat,Rahmani, Maryam,Ahmadinejad, Nasrin,Alipour, Azam,Hashemi, Firoozeh Sadat,Shakiba, Madjid Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.8

Background: The aim of this study was to evaluate and compare the accuracy of diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) value, and time-intensity curve (TIC) type analysis derived from dynamic contrast-enhanced MR imaging (DCE-MRI) in differentiating benign from malignant adnexal masses. Materials and Methods: 47 patients with 56 adnexal masses (27 malignant and 29 benign) underwent DWI and DCE-MRI examinations, prior to surgery. DWI signal intensity, mean ADC value, and TIC type were determined for all the masses. Results: High signal intensity on DWI and type 3 TIC were helpful in differentiating benign from malignant adnexal masses (p<0.001). The mean ADC value was significantly lower in malignant adnexal masses (p<0.001). An ADC value< $1.20{\times}10^{-3}mm^2/s$ may be the optimal cutoff for differentiating between benign and malignant tumors. The negative predictive value for low signal intensity on DWI, and type 1 TIC were 100%. The pairwise comparison among the receiver operating characteristic (ROC) curves showed that the area under the curve (AUC) of TIC was significantly larger than the AUCs of DWI and ADC (p<0.001 for comparison of TIC and DWI, p<0.02 for comparison of TIC and ADC value). Conclusions: DWI, ADC value and TIC type derived from DCE-MRI are all sensitive and relatively specific methods for differentiating benign from malignant adnexal masses. By comparing these functional MR techniques, TIC was found to be more accurate than DWI and ADC.

IL-17A Levels in the Sera of Patients with Gastric Cancer Show Limited Elevation

Malek-Hosseini, Zahra,Taherinejad, Marziye,Malekzadeh, Mahyar,Ghaderi, Abbas,Doroudchi, Mehrnoosh Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.16

Background: Inflammation plays a major role in the development and progression of gastric and other gastrointestinal tumors. The IL-17 family of cytokines has been under investigation as targets of immunotherapy. Materials and Methods: We investigated the levels of IL-17A inflammatory cytokine in the sera of 57 patients with gastric cancer (GC) and 90 healthy age/sex matched controls using ELISA methods. Results: In only 5 (8.8%) of the patients' sera was IL-17A detectable. No IL-17A was apparent in the sera of healthy controls. The maximum concentration of IL-17A in patients was 7.004 pg/ml. Vascular and lymphatic invasions were only seen in one of the 5 positive cases. Although all of them were in the age group >60 years, no correlation was seen between age and IL-17A level. These results are somewhat different from our findings for colorectal cancer (CRC) in the same population. Conclusions: It is possible that the inflammopathology of CRC and GC are rather different, at least in Fars, a southern province of Iran.

A novel combined approach for gas compressors surge suppression based on robust adaptive control and backstepping

Malek Ghanavati,Karim Salahshoor,Mohammad Reza Jahed Motlagh,Amin Ramazani,Ali Moarefianpour 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.2

Nowadays, there is a great interest in using active control methods to increase the compressor working range. The advantage of this controlling method is that the performance point can be located in the vicinity of maximum pressure and efficiency. However, most of the existing controllers require an awareness of compressor characteristic, disturbance upper bound, throttle gain, and throttle valve feature; this is why they are limited in engineering applications. In order to overcome the weakness of the existing controllers, this research employs a novel combined controlling method based on robust adaptive control, which is designed using backstepping technique because the compressor behavior is nonlinear. The increased efficiency and improved operational area for the compressor are provided by this controller without requiring any knowledge or information regarding the compressor characteristic, disturbance upper bound, throttle gain, and throttle valve feature. The adaptive controller has been used to compensate for uncertainties of the compressor characteristic and throttle valve as well as the un-modeled dynamics. Also, the controller robustness is a barrier against the time-varying disturbances in flow and pressure applied to the system. Finally, simulation results showed that the designed controller, in addition to assure the system stability, developed the compressor working range, and the convergence of system states was achieved after applying disturbance in flow and pressure.

Design for Viability of Complex Engineered Systems under Uncertainty

Malek Tahoori,Jafar Gheidar-Kheljani,Mohammad Hossein Karimi Gavara 대한산업공학회 2017 Industrial Engineeering & Management Systems Vol.16 No.4

Complex Engineered Systems generally operate in uncertain environments. Uncertainty can affect the system value delivery through different ways. Viability is the Modern non-functional properties represented as a response to decreasing the impact of dynamic complexities on systems value delivery, therefore system designers used viability principles as an option for executing a design decision or feature in order to respond to variations in the operational context. As there may be numerous system architectures based on different adaptable options, assessing the viability of these architectures under uncertainty as for the basis of compression and selecting the optimized one is an important problem now a day. In this paper for surmounting above problem, a 9 step model is proposed which calculate the viability of assumed architecture under uncertainty by representing the regions in the system that is mostly impacted by the operational uncertainties. To represent the applicability of proposed model a simplified example of Synthetic Aperture Radar satellite observed, the viability of assumed system has been calculated and then some viable options imposed to the system architecture. The recalculated viability value of the assumed system and monitoring of all process steps by experts have shown the applicability and logicality of the model.