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Alzheimer disease (AD) is a neurological disorder with brain network dysfunction. Investigation of the brain network functional connectivity (FC) alterations using resting-state functional MRI (rs-fMRI) can provide valuable information about the brain network pattern in early AD diagnosis.To quantitatively assess FC patterns of resting-state brain networks and graph theory metrics (GTMs) to identify potential features for differentiation of amnestic mild cognitive impairment (aMCI) and late-onset AD from normal.Prospective.A total of 14 normal, 16 aMCI, and 13 late-onset AD.A 3.0 T; rs-fMRI: single-shot 2D-EPI and T1-weighted structure: MPRAGE.By applying bivariate correlation coefficient and Fisher transformation on the time series of predefined ROIs' pairs, correlation coefficient matrixes and ROI-to-ROI connectivity (RRC) were extracted. By thresholding the RRC matrix (with a threshold of 0.15), a graph adjacency matrix was created to compute GTMs.Region of interest (ROI)-based analysis: parametric multivariable statistical analysis (PMSA) with a false discovery rate using (FDR)-corrected P 0.05 cluster-level threshold together with posthoc uncorrected P 0.05 connection-level threshold. Graph-theory analysis (GTA): P-FDR-corrected 0.05. One-way ANOVA and Chi-square tests were used to compare clinical characteristics.PMSA differentiated AD from normal, with a significant decrease in FC of default mode, salience, dorsal attention, frontoparietal, language, visual, and cerebellar networks. Furthermore, significant increase in overall FC of visual and language networks was observed in aMCI compared to normal. GTA revealed a significant decrease in global-efficiency (28.05 45), local-efficiency (22.98 24.05), and betweenness-centrality (14.60 17.39) for AD against normal. Moreover, a significant increase in local-efficiency (33.46 24.05) and clustering-coefficient (25 20.18) were found in aMCI compared to normal.This study demonstrated resting-state FC potential as an indicator to differentiate AD, aMCI, and normal. GTA revealed brain integration and breakdown by providing concise and comprehensible statistics.1 TECHNICAL EFFICACY: Stage 2.

In this paper, the effects of squeeze casting parameters on the wear behavior of A390 aluminum alloy were investigated. For this purpose, the experiment was designed according to L9 Taguchi array that the squeeze pressure (60, 90 and 120 MPa), the superheats of liquid metal (50, 100 and 150 °C) and the die preheating temperature (200, 250 and 300 °C) were selected as the independent variables at three levels. On the contrary, the microstructure characteristics, the weight loss of specimen after wear test and friction coefficient were examined as dependent variables. The microstructural characterizations were also performed using optical microscopy equipped with image analyzer and SEM equipped with EDS. The squeeze casting was performed with a 20-ton hydraulic press in a cylindrical shape. According to the results, the increase in squeezing pressure from 60 to 120 MPa within the tested range leads to a decrease in primary silicon area by 48% and a decrease in silicon eutectic by 44.4%; however, applied pressure did not have any significant effects on morphology of phases. The wear tests were carried out using a computer-controlled pin on disk wear test machine in ambient temperature.

Hepatocellular carcinoma is one of the leading causes of cancer-associated death across the globe. Malignant ascites are the major clinical attributes in cancer patients. Despite the advancements in HCC treatments such as chemotherapy, radiotherapy, surgery, and hormonal therapy, researchers are pursuing novel natural edible compounds for the treatment of cancer to eliminate dreadful side effects. Pleurotus ostreatus is one of the most edible cuisines in Asia as well as all over the world. It has been a source of nutritious diet since it was classified as an edible mushroom with no or negligible side effects. The present study focused on the natural anti-cancerous and anti-ascites capabilities of polysaccharides extracted from Pleurotus ostreatus in-vivo as well as in-vitro. Administration of polysaccharide Pleurotus ostreatus showed a significant decrease in tumor cell metastasis while the increase in the survival period among mice models of H22 malignant ascites. Downregulation of regenerative genes Foxp3 and Stat3 and secretion of immunological factors such as IL-2, TNF α, and INF γ were observed after treating with the partially pure extracted polysaccharide. Twining with the hypothesis of tumor suppression in-vivo model polysaccharide showed a decrease in invasion and migration abilities and henceforth responsible for the gene regulation such Cytochrome C which supposedly induced the chain of gene regulation process resulting in apoptosis in HCC cell lines observed in-vitro experiments. Collective research findings manifested that polysaccharide extracted from Pleurotus ostreatus bears anti-proliferative activity and thus influence tumor suppression in-vivo and in-vitro against hepatocellular carcinoma and can be used for therapeutic purposes as a potential anti-cancerous source in the future.

Task fMRI has played a critical role in recognizing the specific functions of the different regions of human brain during various cognitive activities. This study aimed to investigate group analysis and functional connectivity in the Faradarmangars brain during the Faradarmani CF (FCF) connection. Using task functional MRI (task-fMRI), we attempted the identification of different activated and deactivated brain regions during the Consciousness Filed connection. Clusters that showed significant differences in peak intensity between task and rest group were selected as seeds for seed-voxel analysis. Connectivity of group differences in functional connectivity analysis was determined following each activation and deactivation network. In this study, we report the fMRI-based representation of the FCF connection at the human brain level. The group analysis of FCF connection task revealed activation of frontal lobe (BA6/BA10/BA11). Moreover, seed based functional connectivity analysis showed decreased connectivity within activated clusters and posterior Cingulate Gyrus (BA31). Moreover, we observed an increased connectivity within deactivated clusters and frontal lobe (BA11/BA47) during the FCF connection. Activation clusters as well as the increased and decreased connectivity between different regions of the brain during the FCF connection, firstly, validates the significant effect of the FCF and secondly, indicates a distinctive pattern of connection with this non-material and non-energetic field, in the brain.

A new ripple base signal flow graph (R-SFG) modelling method was proposed to accurately model and analyse a family of switching DC–DC converter. The performance of some DC–DC converters such as single-inductor multi-output converters is dependent on inductor current ripples. This makes the conventional modelling methods cannot fully predict the overall behaviour of converter. From this family and in this study, a single-inductor dual-output (SIDO) boost/boost converter has been modelled based on proposed R-SFG method. The simplicity and systematic procedure presented in this work showed that the R-SFG could be a good alternative for modelling switching converter with complicated structures and with high inductor current ripple. In the new R-SFG method, the effects of inductor current ripple have been considered to develop the conventional signal flow graph modelling method. In this work, a comparative study between two modelling methods has been carried out in a SIDO converter. A step-by-step direct mathematical manipulation was used to calculate the DC–DC transfer function of SIDO converter. The experimental results were included to show the validity of the obtained models. The experimental results showed that the maximum R-SFG modelling error was about 5% over the wide range of inductor current ripple.

Effects of squeeze casting (SQC) parameters, including squeezing pressure, superheats of liquid metal and die preheating temperature on microstructure characteristics and mechanical properties of A390 aluminum alloy, were evaluated using L9 design based on Taguchi method. Squeeze casting was performed by a 25-ton hydraulic press, and all of the parameters were evaluated at 3 different levels: the squeezing pressure was at 60, 90 and 120 MPa, the superheat of the liquid metal was at 50, 100 and 150 °C and the die preheating temperature was at 200, 250 and 300 °C. The microstructure characterization was also performed using optical microscopy image analysis and scanning electron microscope (SEM). Tensile and Brinell test methods were applied for measuring ultimate tensile strength, yield strength, elongation and hardness. The results showed that the SQC process modified cast microstructure and improved mechanical properties of the alloy. In addition, the variations of the SQC parameters, specially the squeezing pressure, have significant effects on the size and volume fractions of the primary silicon, eutectic cells and the mechanical properties. According to the results, increase in squeezing pressure from 60 to 120 MPa within the tested range leads to primary silicon area decrease by 48% and silicon eutectic decrease by 44.4%; however, applied pressure did not have any significant effects on morphology of phases. On the other hand, superheating over 100 °C and die preheating at 200 °C had significant effects on the final result. It is clearly observed that rising pressure to 90 MPa consequently increases the tensile strength, elongation and hardness. But increasing the pressure to over 90 MPa did not have any significant effects on the final result.

HP50M heat-resistant cast austenitic steel tubes are exposed to high temperatures (i.e. 900 °C) for long periods (10 years or longer) in petrochemical reforming plants. Twenty-years aged tubes exhibit microstructural changes such as primary carbide transformation and growth, MC carbide transition to G-phase, and fine secondary M23C6 precipitation. Analytical electron microscopy reveals that silicon tends to segregate at austenite inter-dendritic boundaries in fresh as-cast tubes. Thermo-kinetic simulation of long-term precipitate evolution of the steel is carried out together with Si segregation compositions. The experimentally observed general trend that G-phase forms at the expense of MC carbide is successfully predicted for the Si segregation compositions after a few thousand hours of aging in a temperature range between 700 and 900 °C. This study demonstrates that the Si segregation plays a crucial role in the formation of G-phase in this type of heat-resistant cast steels. Additional heat-treatment experiment confirms that G-phase becomes unstable above 900 °C and the reverse transition to MC occurs.

Smart devices are effective in helping people with impairments, overcome their disabilities, and improve their living standards. Braille is a popular method used for communication by visually impaired people. Touch screen smart devices can be used to take Braille input and instantaneously convert it into a natural language. Most of these schemes require location-specific input that is difficult for visually impaired users. In this study, a position-free accessible touchscreen-based Braille input algorithm is designed and implemented for visually impaired people. It aims to place the least burden on the user, who is only required to tap those dots that are needed for a specific character. The user has input English Braille Grade 1 data (a–z) using a newly designed application. A total dataset comprised of 1258 images was collected. The classification was performed using deep learning techniques, out of which 70%–30% was used for training and validation purposes. The proposed method was thoroughly evaluated on a dataset collected from visually impaired people using Deep Learning (DL) techniques. The results obtained from deep learning techniques are compared with classical machine learning techniques like Naïve Bayes (NB), Decision Trees (DT), SVM, and KNN. We divided the multi-class into two categories, i.e., Category-A (a–m) and Category-B (n–z). The performance was evaluated using Sensitivity, Specificity, Positive Predicted Value (PPV), Negative Predicted Value (NPV), False Positive Rate (FPV), Total Accuracy (TA), and Area under the Curve (AUC). GoogLeNet Model, followed by the Sequential model, SVM, DT, KNN, and NB achieved the highest performance. The results prove that the proposed Braille input method for touch screen devices is more effective and that the deep learning method can predict the user's input with high accuracy.

Heat resistant reformer tubes comprise a significant fraction of petrochemical reforming plants cost considering their high alloy content (i.e. 25Cr-35Ni-1Nb-0.1Ti). The bottom portion of tubes experiences the highest temperatures in the furnaces leading to microstructural changes, creep damage, and loss of elongation over their service life which in this case is twenty years. There is a cost- and time-driven motivation to only replace this portion of tubes by welding in contrast with replacing entire set of tubes which is the common industrial practice. However, welding new to aged tubes may lead to reliability issues due to difference in mechanical properties as a result of microstructural differences. In the current study, the microstructure and tensile properties of aged and new tubes have been evaluated in an effort to qualify the mechanical integrity of weldments. Welding trials are carried out to investigate the microstructure of the aged-to-new weldments and correlate it with the tensile properties (particularly elongation). Findings reveal that the heat affected zone of aged tubes is prone to micro-cracking of bulky primary carbides and incipient melting particularly at the inner surface where the root pass is applied. Adopting preheating for the root pass is effective in reducing carbide micro-cracking by decreasing cooling rate which assists in the accommodation of stresses generated by thermal contraction. Despite presence of carbide micro-cracks, tensile elongation is not severely affected as aged-to-new welds exhibit comparable and slightly higher elongation than aged base metals (above 4%). It is proposed that this is partially due to the orientation of micro-cracks in carbides. Further microstructural and tensile property results are presented and discussed.

In this paper, the sand casting process was evaluated using ProCAST simulating software and practical experience for manufacturing of the high chromium stainless steel outlet diaphragms used in iron ore ball mill. In the simulation practice, the effects of feeding and gating designs on the liquid flow, heat transfer and solidification phenomenon were evaluated to minimize the liquid surface turbulence during filling of the mold cavity and the shrinkage porosity formation during the liquid solidification in the mold. The effects of different gating ratios and number of feeders were numerically studied using different indicators in the software such as linear velocity, niyama criteria, fraction solid and shrinkage porosity. Further, the optimal design obtained by simulating process was empirically examined. The simulation results showed that the 1:3:4 gating ratio is the proper gating system that it obtains an unpressurized fluid flow without any surface turbulent of the liquid steel in the filling step. In addition, the simulation of solidification phenomenon was indicated that four feeders are required to eliminate of the shrinkage porosities. The empirical casting examination shown the optimal design by the simulation is proper for manufacturing of the steel part without critical defects.

After World War II, world order was based on two basic principles of thought and value and a practical basis (military and political). The first was the claim of the supremacy and value of the West and its consolidation on other nations. The second point was the issue of political and military capabilities. If nations or governments were not affected by that system of value and thought and did not surrender, they were forced to accompany by political and military pressures.Both factors are changing today; the most important reason is the intellectual and practical conflicts of the domination system. This research focuses on the views of the Iranian leader about the system of domination and its conflicts, the main question is: What are the conflicts of domination system in international relations in practical termswith the theoretical field, in the discourse of Ayatollah Khamenei? "Results of the study indicate the contradictions of the dominant system in theory and practiceon issues like human rights, terrorism, weapons of mass destruction and democracy. In discourse of Iranian leader, these contradictions revealed the vulnerability of the domination systemand it will facilitate the process of collapse.

This study describes the systematic signal flow graph (SFG) modelling of a single inductor triple output (SITO) DC/DC converters. The multi-stages operation of SITO converter and the parasitic elements cause obtaining a model to predict the all behaviours of converter be more difficult than typical converters. By SFG method, all small-signal transfer functions can be derived. Derivations of large-signal, small-signal and steady-state models are demonstrated by considering a single inductor triple output boost/boost convert. The effect of inductor ripple current has been considered to determine the acceptable region of SFG modelling method. Simulation and experimental results are included to show the validity of the obtained model.

The effects of precipitated phases on the magnetic properties of 2304 duplex stainless steel (UNS S32304) were investigated. For this purpose, various artificial aging treatments were carried out at different temperatures (700, 800, and 900 centigrade) and times (20, 30, 60 120 min). The microstructural evaluations were performed by optical and scanning electron microscopy (SEM) equipped with energy-dispersive x-ray spectroscopy (EDS) and x-ray diffraction (XRD) method. In order to assess the magnetic properties, hysteresis loop was determined using the vibrating-sample magnetometer (VSM) method. The results showed that the aging treatment produces precipitates such as carbides chromium (M23C6), Cr2N chromium nitride, sigma phase and the secondary austenite in the ferrite/austenite interface that grows in to the ferrite grains and decreases the magnetic compound of the microstructure. The ferrite volume fraction decreases from 92.5% to 68.1% by increasing of the aging transformation intensity (ATI). This phenomenon drastically damages the magnetic properties. The saturation magnetization of the steel decreases from 123 emu/g to 91 emu/g with increasing of ATI. The lowest level of MS and highest aging transformation intensity occurred at the aging temperature of 800 °C for 120 min.

Nanostructure of cupper thin film on polyimide flexible substrate is revealed by novel orientation imaging techniques. Copper and polyimide thicknesses play critical roles on what technique is successful in acquiring diffraction patterns while avoiding electron beam damage and blistering. Conventional electron backscattered diffraction as well as emerging higher resolution transmission orientation imaging were employed to resolve the grain structure. Spatial resolution is compared in terms of minimum detectable twin width. Experiments and simulations indicate that polyimide thicknesses below 1000 nm allow the electrons to scape; resulting in acceptable reflective or transmission patterns and lack of blistering.

The wear and failure analysis of shell liners of a grinding mill is investigated. Metallurgical and tribological studies were conducted on the worn liner of a semi-autogenous grinding mill in Chadormalu Industrial Complex. The chemical analysis, wear mechanism, microstructural variations and mechanical properties in different sections of the worn liner were evaluated using visual inspection, optical and scanning electron microscopes and hardness measurements. Chemical analyses indicated that the shell linear is hypereutectoid low-alloy chromium steel. According to visual inspection, it was observed that the maximum weight loss happened in the lifter zone where the grinding mill charge is thrown on. In addition, the microstructure and hardness of the lifter of liner from the initial surface to interior depth have meaningful differences that can intensify the wear rate. The main microstructure at the initial working surface consisted of tempered martensite with noticeable content of retained austenite with hardness more than 47 HRC. The well-worn surfaces had coarse pearlitic features with cementite networks at the prior austenite grain boundaries with 29 HRC hardness. It was concluded that both the retained austenite in martensitic matrix and cementite networks in coarse pearlite decreased wear resistance severely. For improvement of wear behavior of the casting, lowering the carbon and chromium contents and applying proper heat treatment cycle to obtain a fully pearlitic microstructure with 34–40 HRC are recommended.

Cu/Ti nanostructured bimetal composite was produced by accumulative roll-bonding (ARB) technique and the structural characteristics of this composite were studied both experimentally and by finite element analysis. Macrostructure evolution of the composite layers was investigated by optical and scanning electron microscopes. In addition, transmission electron microscopy (TEM) as well as energy-dispersive X-ray spectroscopy (EDX) techniques were utilized for detailed microstructural investigations. Different finite element simulations were designed based on the experimental results. The results were combined with macrostructural observations to gain a better insight into the fragmentation mechanism of the Ti reinforcements. Necking of the Ti layers was observed after 3 cycles of ARB processing which was found to happen at shear bands, after sufficient work-hardening of the constituents. Further processing resulted in fragmentation and distribution of lens shaped Ti constituents. It was found that such a shape evolution makes it more difficult to deform the Ti segments by further straining and consequently, a more localized strain concentration happens within the Cu matrix near these segments. A significant grain refinement was observed by TEM investigation of the highly strained composite. ARB processing of Cu/Ti bimetal composite resulted in nanostructured Ti reinforcements distributed within an ultrafine-grained Cu matrix. Keywords: Accumulative roll-bonding, Nanostructured bimetal composite, Macrostructure, Finite element analysis, Microstructure

Effects of surface deformation and grain size on the humid air oxidation of INCONEL 740 have been investigated. Scanning and transmission electron microscopy as well as X-ray spectroscopy are utilized to characterize and quantify the oxides. Results indicate that severe deformation refines surface micro-grains to nano-grains, leading to an increase in the mass gain and oxide thickness. Surface deformation prior to oxidation enhances the metal-oxide interface adherence. This enhancement is associated with the mechanical interlocking at the interface which ultimately improves the resistance to exfoliation. The grain size effect on the oxidation of non-deformed samples was found insignificant due to Cr-oxide exfoliation and evaporation.