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Nanoparticle green synthesis is an emerging scientific field that focuses on the production of nanoparticles by living cells. In this work, the potential of extracts of alfalfa leaves (Medicago sativa) as affordable and fabricated zirconium nanoparticles (ZrNPs) was evaluated for the first time. alfalfa alcoholic extract and zirconium precursor were used to produce ZrNPs, the production and characteristics of nanoparticles were measured using the Tyndall effect, UV‐vis, FT‐IR, EDX, DLS, and SEM tests, antioxidant and antibacterial properties, and toxicity Measurement of nanoparticles on breast cancer (MDA‐MB‐468) and human healthy cells (HFF) was investigated. The optimization of nanoparticle production was evaluated with ANN and GN algorithms. The analysis showed that nanoparticles have spherical‐like ZrNPs shapes with an average of 50 nm size. in addition, ZrNPs have significant cytotoxic effects against human breast cancer (MDA‐MB‐468) cells, and Human foreskin fibroblast (HFF) cells exhibited the highest resistance to ZrNPs. There was a significant agreement between the results of the designed ANN‐GA model and the experimental data. In this research, ZrNP was successfully created using alfalfa extract as a renewable source of stabilizing and reducing agents with an environmentally friendly approach, and they showed significant antioxidant, antibacterial, and anticancer properties. [ABSTRACT FROM AUTHOR]

Different growth stages of Penicillium notatum, P. purpurogenum and P. aculeatum were evaluated for their potential for zirconium nanoparticle (Zr-NP) biosynthesis by total protein content assay. Fungal secreted protein concentrations for all three species were higher at deceleration phase. For optimizing biosynthesis conditions with respect to Zr-NP size, different pH values and ZrCl4 concentrations were tested and analyzed. The artificial neural network (ANN) modeling was then applied to find the best conditions. A feed-forward ANN model was used to make a connection between the output as the size of Zr-NPs, with three input variables, including pH, ZrCl4 concentration and fungal species. An optimal multi-layer perceptron neural network was finally designed to model the experimental data for which the correlation coefficients R2 at each phase (training, validation and test sets) were calculated to be 0.9946, 0.9952 and 0.9997, respectively. The accuracy of the model was confirmed through validation experiments. [ABSTRACT FROM AUTHOR]

This paper presents a single-axis angular rate sensor that is robust to variations in its operating voltage and frequencies. The sensor is developed to overcome the shortcomings of conventional mode-matched Micromachined Vibratory Gyroscopes in open loop operations, namely narrow frequency bandwidths and unstable scale factors. The developed sensor utilizes inherent forcing and inertial nonlinearities from electrostatic forces and fabrication imperfections to auto-parametrically excite the sense mode via 2:1 auto-parametric resonance, which yields a broader bandwidth frequency response for the sensor's sense mode. The experimental results demonstrated − 3   dB frequency bandwidth of 500   Hz , a scale factor of 50   μ V / ° / s , and a dynamic range of ± 330 ° / s . [ABSTRACT FROM AUTHOR]

Six provinces of Iran were surveyed during 2012–2014 to detect potyviruses infecting common bean crops. A total of 277 leaf samples were collected from bean plants and some other legumes as well as weeds and wild legumes showing virus-like symptoms. Enzyme-linked immunosorbent assay (ELISA) using broad-spectrum potyvirus antibodies gave a positive reaction with 63 samples (22.7%). Moreover, a mixed colony of aphids (Aphis craccivora and A. fabae), collected from a locust tree plant (Robinia sp.), transmitted a potyvirus to young healthy bean plants; the infection was confirmed through serological assays. Partial nuclear inclusion b (NIb) and coat protein (CP) regions of the genomes of 19 ELISA-positive samples were amplified by reverse-transcription polymerase chain reaction (RT-PCR) using NIb and NWCIEN (or WCIEN) universal primer sets, respectively. Potyvirus species identification was confirmed by BLASTN and phylogenetic analyses followed by ELISA tests using virus-specific antibodies or biological assays. The results clearly showed the presence of Bean common mosaic virus (BCMV), Bean common mosaic necrosis virus (BCMNV), Bean yellow mosaic virus (BYMV) and Wisteria vein mosaic virus (WVMV) in the samples tested. Non-specific amplification of a Cucumovirus genome by using NIb primers was also recorded. The results showed the natural occurrence of a new potyvirus species (WVMV), and a new host for BYMV (Trifolium repens) in the mid-Eurasian region of Iran. Our findings indicate the capacity of the universal detection systems for fast and accurate detection of legume potyviruses in the country and for use in routine diagnostic assays. [ABSTRACT FROM AUTHOR]

Diffuse optical spectroscopy is a relatively new, noninvasive and nonionizing technique for breast cancer diagnosis. In the present study, we have introduced a novel handheld diffuse optical breast scan (DOB-Scan) probe to measure optical properties of the breast in vivo and create functional and compositional images of the tissue. In addition, the probe gives more information about breast tissue's constituents, which helps distinguish a healthy and cancerous tissue. Two symmetrical light sources, each including four different wavelengths, are used to illuminate the breast tissue. A high-resolution linear array detector measures the intensity of the back-scattered photons at different radial destinations from the illumination sources on the surface of the breast tissue, and a unique image reconstruction algorithm is used to create four cross-sectional images for four different wavelengths. Different from fiber optic-based illumination techniques, the proposed method in this paper integrates multi-wavelength light-emitting diodes to act as pencil beam sources into a scattering medium like breast tissue. This unique design and its compact structure reduce the complexity, size and cost of a potential probe. Although the introduced technique miniaturizes the probe, this study points to the reliability of this technique in the phantom study and clinical breast imaging. We have received ethical approval to test the DOB-Scan probe on patients and we are currently testing the DOB-Scan probe on subjects who are diagnosed with breast cancer. [ABSTRACT FROM AUTHOR]

A Tospovirus species was isolated from peanut plants showing chlorotic ring spots and chlorosis, and identified as Tomato yellow fruit ring virus (TYFRV) on the basis of its biological, serological, and molecular properties. In host range studies, a broad range of indicator plants was infected by the five isolates studied; all the isolates systemically infected Nicotiana tabacum cultivars and, thus, they were classified into the N-host-infecting type isolates of the virus. These isolates strongly reacted with TYFRV antibodies but not with the specific antibodies of other tospoviruses tested. Recombination analyses showed that the nucleoprotein gene of the peanut isolates and other isolates studied were nonrecombinant. In phylogenetic trees, the virus isolates were clustered in three genogroups: IRN-1, IRN-2, and a new group, POL; the peanut isolates fell into IRN-2 group. Multiple sequence alignments showed some genogroup-specific amino acid substitutions among the virus isolates studied. The results revealed the presence of negative selection in TYFRV populations. Also, the Iranian populations had higher nucleotide diversity compared with the Polish population. Genetic differentiation and gene flow analyses indicated that the populations from Iran and Poland and those belonging to different genogroups were partially differentiated populations. Our findings seem to suggest that there has been frequent gene flow between some populations of the virus in the mid-Eurasian region of Iran. [ABSTRACT FROM AUTHOR]

Many animals are known to exhibit foraging patterns where the distances they travel in a given direction are drawn from a heavy-tailed Lévy distribution. Previous studies have shown that, under sparse and random resource conditions, solitary non-destructive (with regenerating resources) foragers perform a maximally efficient search with Lévy exponent μ equal to 2, while for destructive foragers, efficiency decreases with μ monotonically and there is no optimal μ. However, in nature, there also exist situations where multiple foragers, displaying avoidance behavior, interact with each other competitively. To understand the effects of such competition, we develop a stochastic agent-based simulation that models competitive foraging among mutually avoiding individuals by incorporating an avoidance zone, or territory, of a certain size around each forager which is not accessible for foraging by other competitors. For non-destructive foraging, our results show that with increasing size of the territory and number of agents the optimal Lévy exponent is still approximately 2 while the overall efficiency of the search decreases. At low values of the Lévy exponent, however, increasing territory size actually increases efficiency. For destructive foraging, we show that certain kinds of avoidance can lead to qualitatively different behavior from solitary foraging, such as the existence of an optimal search with 1 < μ < 2. Finally, we show that the variance among the efficiencies of the agents increases with increasing Lévy exponent for both solitary and competing foragers, suggesting that reducing variance might be a selective pressure for foragers adopting lower values of μ. Taken together, our results suggest that, for multiple foragers, mutual avoidance and efficiency variance among individuals can lead to optimal Lévy searches with exponents different from those for solitary foragers. • Develop a minimal model for Levy-type foraging in the presence of territorial competition. • Territorial competition can lead to improved efficiency of long-ranged searches. • Selective pressure on minimizing the variance of the efficiency favors more long-ranged strategies. • Aerial territorial competition leads to shorter-ranged optimal strategies for destructive foraging. [ABSTRACT FROM AUTHOR]

Drawing upon postcolonial and postcolonial feminist lenses, this study critically analyzes the discourses, evident in the popular press, that serve to construct identities associated with veil-wearing Muslim women. Through print and digital media articles from January 2009 to December 2011, we trace the discursive character of the veil-wearing Muslim woman through conversations before, during, and after Bill 94 was tabled by the Quebec government. Concerned not only with the Western construction of the “other,” we attempted to provide the space necessary to hear Muslim women. Considerable focus was placed on teasing out interviews with Muslim women or responses by Muslim women. Findings suggest that several contradictions exist in terms of Western constructions and how Muslim women in Canada construct their own identities. At the center of these contradictions lies the symbolism of the veil, representing oppression and submission to some and empowerment and resistance to others. [ABSTRACT FROM AUTHOR]

Diffuse Optical Spectroscopy (DOS) is a promising non-invasive and non-ionizing technique for breast anomaly detection. In this study, we have developed a new handheld DOS probe to measure optical properties of breast tissue. In the proposed probe, the breast tissue is illuminated with four near infrared (NIR) wavelengths light emitting diodes (LED), which are encapsulated in a package (eLEDs), and two PIN photodiodes measure the intensity of the scattered photons at two different locations. The proposed technique of using eLEDs is introduced, in order to have a multi-wavelength pointed-beam illumination source instead of using the laser-coupled fiber-optic technique, which increases the complexity, size, and cost of the probe. Despite the fact that the proposed technique miniaturizes the probe and reduces the complexity of the DOS, the study proves that it is accurate and reliable in measuring optical properties of the tissue. The measurements are performed at the rate of 10Hz which is suitable for dynamic measurement of biological activity, in-vivo. The multi-spectral evaluation algorithm is used to reconstruct four main absorber concentrations in the breast including oxy-hemoglobin (cHb), deoxy-hemoglobin (cHbO2), water (cH2O), fat (cFat), and average scattering coefficient of the medium, as well as concentration changes in Hb (cHb) and HbO2 (cHbO2). Although the probe is designed for breast cancer diagnosis, it can be used in a wide range of applications for both static and dynamic measurements such as functional brain imaging. A series of phantoms, comprised of Delrin, Intralipid, PierceTM and Black ink, are used to verify performance of the device. The probe will be tested on human subjects, in-vivo, in the next phase. [ABSTRACT FROM AUTHOR]

Cells self-organize into functional, ordered structures during tissue morphogenesis, a process that is evocative of colloidal self-assembly into engineered soft materials. Understanding how intercellular mechanical interactions may drive the formation of ordered and functional multicellular structures is important in developmental biology and tissue engineering. Here, by combining an agent-based model for contractile cells on elastic substrates with endothelial cell culture experiments, we show that substrate deformation-mediated mechanical interactions between cells can cluster and align them into branched networks. Motivated by the structure and function of vasculogenic networks, we predict how measures of network connectivity like percolation probability and fractal dimension as well as local morphological features including junctions, branches, and rings depend on cell contractility and density and on substrate elastic properties including stiffness and compressibility. We predict and confirm with experiments that cell network formation is substrate stiffness dependent, being optimal at intermediate stiffness. We also show the agreement between experimental data and predicted cell cluster types by mapping a combined phase diagram in cell density substrate stiffness. Overall, we show that long-range, mechanical interactions provide an optimal and general strategy for multicellular self-organization, leading to more robust and efficient realizations of space-spanning networks than through just local intercellular interactions. [ABSTRACT FROM AUTHOR]

Tissue classification using computer aided diagnosis can help automated decision making to aid clinical diagnosis. Classification of breast tissue based on spectral features of impedance loci has frequently been done to classify malignant tissue with further requirement of more complex classification methodologies needed to improve the characterisation. In current study, tissue classification is done using in vivo electrical impedance data of 18 human subjects, from four quadrants of breast, palm, nail, arm, bicep and classified using algorithms involving machine learning methodologies, specifically support vector machines (SVMs) that are supervised learning models. They consist of learning algorithms based on the principal of structural risk minimisation. Two methodologies of SVM have been used in this study: with data binning and data pruning and without data binning and data pruning. Data binning and data pruning have improved the sensitivity of the SVM from 76.76 to 89.23%, but the specificity has decreased from 76.23 to 74.15%. This is a pilot study towards testing the reliability of the developed electrical impedance measuring system and developing a data mining‐based decision making system into an electrical impedance spectroscopy system, to help users (physicians) with tissue classification leading to reliable objective decision making. [ABSTRACT FROM AUTHOR]

Abstract: When a proton exchange membrane (PEM) fuel cell runs short of hydrogen, it suffers from a reverse potential fault that, when driven by neighboring cells, can lead to anode catalyst degradation and holes in the membrane due to local heat generation. As a result, hydrogen leaks through the electrically-shorted membrane-electrode assembly (MEA) without being reacted, and a reduction in fuel cell voltage is noticed. Such voltage reduction can be detected by using electrochemical impedance spectroscopy (EIS). To fully understand the reverse potential fault, the effect of hydrogen crossover leakage in a commercial MEA is measured by EIS at different differential pressures between the anode and cathode. Then the signatures of these leaky cells were compared with the signatures of a no-leaky cells at different oxygen concentrations with the same current densities. The eventual intent of this early stage work is to develop an on-board diagnostics system that can be used to detect and possibly prevent cell reversal failures, and to permit understanding the status of crossover or transfer leaks versus time in operation. [Copyright &y& Elsevier]

The conversion of rotary to translational motion in lead screw drives occurs at the meshing lead screw and nut threads. Adecreasing coefficient of friction with sliding velocity, may lead to instabilities in these drives. In this paper, a sliding mode controller is designed for a two degrees of freedom lead screw drive model. This controller has two objectives: to regulate the lead screw angular velocity to a preset value and to attenuate friction-induced vibrations. Only upper and/or lower bounds of system parameters are assumed to be known. In addition, in the development of the controller no specific model is assumed for the dependence of the coefficient of friction on the relative sliding velocity. Two modifications are applied to the basic discontinuous sliding mode controller to eliminate the inherent chattering problem and to limit thecontrolled input torque levels. Numerical simulation results are presented that show the applicability and the performance of the proposed controller. [ABSTRACT FROM PUBLISHER]

This paper presents a new triaxial accelerometer calibration method using a mathematical model of six calibration parameters: three gain factors and three biases. The fundamental principle of the proposed calibration method is that the sum of the triaxial accelerometer outputs is equal to the gravity vector when the accelerometer is stationary. The proposed method requires the triaxial accelerometer to be placed in six different tilt angles to estimate the six calibration parameters. Since the mathematical model of the calibration parameters is nonlinear, an iterative method is used. The results are verified via simulations by comparing the estimated gain factors and biases with the true gain factors and biases. The simulation results confirm that the proposed method is applicable in extreme cases where the gain factor is 1000 V/(m/s²) and the bias is ±100 V, as well as the cases where the gain factor is 0.001 V/(m/s²) and the bias is 0 V. The proposed calibration method is also experimentally tested with two different triaxial accelerometers, and the results are validated using a mechanical inclinometer. The experimental results show that the proposed method can accurately estimate gain factors and biases even when the initial guesses are not close to the true values. In addition, the proposed method has a low computational cost because the calculation is simple, and the iterative method usually converges within three iteration steps. The error sources of the experiments are discussed in this paper. [ABSTRACT FROM AUTHOR]

This paper describes the development of a modified Kalman filter to integrate a multi-camera vision system and strapdown inertial navigation system (SDINS) for tracking a hand-held moving device for slow or nearly static applications over extended periods of time. In this algorithm, the magnitude of the changes in position and velocity are estimated and then added to the previous estimation of the position and velocity, respectively. The experimental results of the hybrid vision/SDINS design show that the position error of the tool tip in all directions is about one millimeter RMS. The proposed Kalman filter removes the effect of the gravitational force in the state-space model. As a result, the resulting error is eliminated and the resulting position is smoother and ripple-free. [ABSTRACT FROM AUTHOR]

This paper utilizes an intelligent system which incorporates Kalman filters (KFs) and a fuzzy expert system to track the tip of a fastening tool and to identify the fastened bolt. This system employs one inertial measurement unit and one position sensor to determine the orientation and the center of mass location of the tool. KFs are used to estimate the orientation of the tool and the center of mass location of the tool. Although a KF is used for the orientation estimation, orientation error increases over time due to the integration of angular velocity error. Therefore, a methodology to correct the orientation error is required when the system is used for an extended period of time. This paper proposes a method to correct the tilt angle and orientation errors using a fuzzy expert system. When a tool fastens a bolt, the system identifies the fastened bolt using a fuzzy expert system. Through this bolt identification step, the 3-D orientation error of the tool is corrected by using the location and orientation of the fastened bolt and the position sensor outputs. Using the orientation correction method will, in turn, result in improved reliability in determining the tool tip location. The fastening tool tracking system was experimentally tested in a lab environment, and the results indicate that such a system can successfully identify the fastened bolts. [ABSTRACT FROM AUTHOR]

In this paper a novel active compliance chamber is designed, which can be used to control the dynamic stiffness of a common hydraulic bushing. This chamber offers a simple and cost-effective solution for the variable displacement engine (VDE) isolation problem. A VDE system requires a soft bushing for the half cylinder mode and a regular one for normal engine operations. A magnetic actuator is used to produce mechanical pulses. The linearisation technique is used for simplifying the nonlinear equation of motion. Different current sources are used to feed the magnetic actuator. The pressure inside the chamber follows linearly the current input signal. The phase shift in various current inputs is used in the form of the transfer functions to create the required pressure response pattern in the frequency domain. Since the dynamic stiffness of a conventional hydraulic bushing is a direct function of the pressure inside it, the active compliance chamber can be used to alter the pressure and consequently produce the required dynamic stiffness response. As a result, it can address the engine vibration problem for VDE situation. [ABSTRACT FROM AUTHOR]

A distinct isolate (TY-PF36) of Tomato yellow fruit ring virus (TYFRV) was obtained from potato (Solanum tuberosum) in Iran. Chlorosis and necrotic spots on leaves associated with leaf and stem necrosis symptoms appear on the affected plants. Of 32 plant species and cultivars mechanically inoculated, 24 were susceptible to the virus isolate. The isolate strongly reacted with TYFRV antibodies in enzyme-linked immunosorbent assay (ELISA), but not with the spe- cific antibodies of other tospoviruses tested. TYFRV-specific N gene primers described previ- ously, however, failed to produce DNA fragments from the total RNA extracts of the infected plants in reverse transcription-polymerase chain reaction (RT-PCR). Nucleotide sequencing of the complete N gene and partial L gene of this isolate revealed considerable differences to those reported for TYFRV with identities ranging from 83.9 to 84.2% and 84.9 to 85.4%, respectively. Two specific primers were designed for detecting TY-PF36 using RT-PCR; TY-PF36 was de- tected in symptomatic field samples of potato, peanut, soybean, and two weed species, Datura metel and D. St ramonium. [ABSTRACT FROM AUTHOR]

Purpose - This paper represents a hybrid Vision/INS system for tool tracking applications. The proposed system incorporates low cost MEMS sensors and low cost vision type sensors for tracking industrial tools. Vision systems alone have to deal with the problem of "line of sight" and the INS sensor alone will encounter an exponential drift, which render both systems useless for the proposed application. Design/methodology/approach - The Vision/INS system with the integration of the extended Kalman filter calculates 6D position-orientation of a tool during its operation within the required accuracy tolerance specific to the application at hand. In this paper, a tool motion modeling approach is proposed to limit the error in an acceptable range for a short period of missing data. The motion of the tool is modeled and updated at any time that the instrument is in the camera view field. This model is applied to the estimation algorithm whenever the camera is not in line of site and the optical data is missing. Findings - The result of applying motion modeling is shown that the resulted error due to absence of the vision measurement system was bounded and decreased (see the experimental results). Originality/value - In this paper, the tool motion modeling is proposed to bind the error in the acceptable range for a short period of missing data. The motion of the tool is modeled and updated at any time that the instrument is in the camera view field. This model is applied to the estimation algorithm whenever the camera is not in line of site and the optical data is missing. [ABSTRACT FROM AUTHOR]

In this paper, a load-leveling suspension system with a magnetorheological (MR) damper is investigated. In this suspension system, the MR damper is connected to a spring to form a load-leveling suspension system. The system effective stiffness and damping can be adjusted by controlling the MR damper. The characteristics of a load-leveling suspension system are studied first. When the linear damper is replaced with an MR damper, the averaging method is adopted to obtain the steady-state response of the nonlinear system. A comparison demonstrates that the results of the averaging method are in good agreement with those obtained by numerical simulations. The analytical results are then verified experimentally. The load-leveling suspension system studied here is able to adjust both suspension stiffness and damping and, hence, it may provide more effective vibration control in a wider frequency range, when the damper is controlled. [ABSTRACT FROM AUTHOR]

Three semi-active control methods are investigated for use in a suspension system using a commercial magnetorheological damper. The three control methods are the limited relative displacement method, the modified skyhook method, and the modified Rakheja-Sankar method. The method of averaging has been adopted to provide an analytical platform for analyzing the performance of the different control methods. The analytical results are verified using numerical simulation, and further are used to assess the efficiency of different control methods. An experimental test bed has been developed to examine the three control methods under sinusoidal and random excitations. Both analytical and experimental results confirm that the Rakheja-Sankar control and modified skyhook control methods significantly reduce the root-mean-square response of both the acceleration and relative displacement of the sprung mass, while the limited relative displacement controller can only control the relative displacement of the suspension system. [ABSTRACT FROM AUTHOR]

Piecewise linear vibration isolators are designed to optimally balance the competing goals of motion control and isolation. The piecewise linear system represents a hard nonlinearity, which cannot be assumed small, and hence standard perturbation methods are unable to provide a complete analytical solution. To date there is no frequency response equation reported for piecewise linear isolator systems to include both dual damping and stiffness behavior. In this investigation an averaging method was adopted to explore the frequency response of a symmetric piecewise linear isolator at resonance. The result obtained by an averaging method is in agreement with numerical simulation and experimental measurements. Preliminary sensitivity analysis is conducted to find the effect of system parameters. It appears that the damping ratio plays a more dominant role than stiffness in piecewise linear vibration isolators. [ABSTRACT FROM AUTHOR]

A survey was conducted to determine the incidence of Alfalfa mosaic virus (AlMV), Bean common mosaic virus (BCMV), Bean yellow mosaic virus (BYMV), Blackeye cowpea mosaic virus (BlCMV), Cucumber mosaic virus (CMV), Pea enation mosaic virus (PEMV), Peanut mottle virus (PeMoV), Soybean mosaic virus (SMV), Tobacco mosaic virus (TMV), Tobacco ringspot virus (TRSV), Tobacco streak virus (TSV), Tomato ringspot virus (ToRSV), and Tomato spotted wilt virus (TSWV) on soybean (Glycine max) in Iran. Totals of 3,110 random and 1,225 symptomatic leaf samples were collected during the summers of 1999 and 2000 in five provinces of Iran, where commercial soybean is grown, and tested by enzyme-linked immunosorbent assay (ELISA) using specific polyclonal antibodies. Serological diagnoses were confirmed by electron microscopy and host range studies. The highest virus incidence among the surveyed provinces was recorded in Mazandaran (18.6%), followed by Golestan (15.7%), Khuzestan (14.2%), Ardabil (13.9%), and Lorestan (13.5%). Incidence of viruses in decreasing order was SMV (13.3%), TSWV (5.4%), TRSV (4.2%), TSV (4.1%), PEMV (2.9%), BYMV (2.2%), ToRSV (2.1%), AlMV (1.3%), BCMV (0.8%), and CMV (0.6%). Additionally, 1.5% of collected leaf samples had positive reactions in ELISA with antiserum to TMV, indicating the possible infection of soybeans in Iran with a Tobamovirus that is related serologically to TMV. Of 195 leaves from plants showing soybean pod set failure syndrome (PSF) in Mazandaran and Lorestan, only 14 (7.2%) samples had viral infection. No correlation was observed between PSF and presence of the 13 viruses tested, suggesting the involvement of other viruses or factors in this syndrome. To investigate the presence of seed-borne viruses, including SMV, TRSV, ToRSV, and TSV, 7,830 soybean seeds were collected randomly at harvesting time from the major sites of soybean seed production located in Mazandaran and Golestan provinces. According to ELISA analyses of germinated seedlings, 7.1 and 8.9% of the seed samples from Golestan and Mazandaran provinces, respectively, transmitted either SMV, TRSV, ToRSV, or TSV through seed. We also showed that SMV and other seed transmissible viruses, as well as TSWV, usually are the most prevalent viruses in soybean fields in Iran. In this survey, natural occurrence of AlMV, BCMV, BlCMV, BYMV, CMV, PEMV, PeMoV, and TSWV was reported for the first time on soybeans in Iran. [ABSTRACT FROM AUTHOR]

A reliable machine fault prognostic system can be used to forecast damage propagation trend in rotary machinery and to provide an alarm before a fault reaches critical levels. Currently, there are several techniques available in the literature for time-series prediction. Among the most promising methods are recurrent neural networks (RNNs) and neuro-fuzzy (NF) systems. In this paper, the performance of these two types of predictors is evaluated using two benchmark data sets. Through comparison it is found that if an NF system is properly trained, it performs better than RNNs in both forecasting accuracy and training efficiency. Accordingly, NF system is adopted to develop an on-line machine fault prognostic system. In order to facilitate the automatic monitoring process, reference function approach is proposed here to enhance feature representation. The performance of the developed prognostic system is evaluated by using three test cases including a worn gear, a chipped gear, and a cracked gear, as well as using data sets from previous studies corresponding to a gear pitting damage and a shaft misalignment. From these tests, the NF prognostic system is found to be a very reliable and robust machine health condition predictor. It can capture the system dynamic behaviour quickly and accurately. [Copyright &y& Elsevier]

The main concern in printing quality in multistage presses is doubling. Doubling is caused by imperfections either within stages (units) or in links connecting different stages, mainly resulting from machine vibration, gear damage, and excessive run-out. In this paper, we propose new means for printing quality control via geared system health condition monitoring. The diagnosis is based on the signals acquired from inexpensive magnetic pickups. A new technique is developed to monitor the gear rotation synchronization among different stages in order to isolate possible sources of the doubling problem. A new approach is proposed to determine the gear run-out. Moreover, gear tooth damage detection is conducted using the beta kurtosis and the continuous wavelet transform based on the overall residual signal. The beta kurtosis of original signal average is also shown here to be useful in detecting excessive gear run-out. Test results from printing presses demonstrated the viability of the proposed methods. [Copyright &y& Elsevier]

In this paper, we analyze the frequency response of a piecewise linear suspension system. Dynamical characteristics of the suspension will suddenly change when its relative displacement exceeds a clearance. Piecewise linear characteristics occur, for example, wherever we use stoppers to prevent the system from excessive relative displacement. A modified averaging method is used to find the frequency response of the system to a harmonic base excitation. A frequency island is observed, which corresponds to large amplitude vibration for a certain range of system parameters. The island is an isolated region that cannot be reached by the variation of excitation frequency and depends upon initial conditions. On the frequency island, the isolator amplifies the amplitude of vibration rather than suppressing it. This will be dangerous in applications where stoppers are installed to ensure relative displacement is limited. The ranges of system parameters causing the frequency island arc determined. The results obtained by an analytical method are verified using numerical simulation. [ABSTRACT FROM AUTHOR]

A simple approach for the suppression of the tremor associated with Parkinson's disease is presented. The proposed system is a tuned vibration absorber (TVA), which has been very effective in the suppression of vibrations in an experimental model of the human arm with two degrees of freedom. Theoretical and numerical methods were used to study the behaviour of the arm model and to develop an effective tremor reduction approach. Based on these studies, a vibration absorber was designed, tested numerically and fabricated for experimental testing. Experimental investigations indicated that optimum control performance was related to the position of the controller and the excitation frequency. With a distance of 160 mm from the end of forearm, the TVA was found to have the best performance, and, for different tremor frequencies, the vibration of the experimental model was reduced by more than 80%. [ABSTRACT FROM AUTHOR]

The focus of this work is to develop a technique to obtain numerical solution over a long range of time for non-linear multi-body dynamic systems undergoing large amplitude motion. The system considered is an idealization of an important class of problems characterized by non-linear interaction between continuously distributed mass and stiffness and lumped mass and stiffness. This characteristic results in some distinctive features in the system response and also poses significant challenges in obtaining a solution.In this paper, equations of motion are developed for large amplitude motion of a beam carrying a moving spring–mass. The equations of motion are solved using a new approach that uses average acceleration method to reduce non-linear ordinary differential equations to non-linear algebraic equations. The resulting non-linear algebraic equations are solved using an iterative method developed in this paper. Dynamics of the system is investigated using a time-frequency analysis technique. [Copyright &y& Elsevier]

Focuses on a study that examined the essential aspects involved in the design of an active vibration control system. Development of active vibration control system; Discussion on structure modelling, model reduction, feedback control, and feedforward control; Details of eigenstructure assignment and coordinate coupling control.

Provides a history of engine mount research for automotive applications. Important duties and principal functions of engine mounts; Key considerations in the design of engine mounts; Factors that cause nonlinearities or discontinuities in mounts; Types of damping that affect the motion of an engine.

This paper concerns nonlinear modeling of a hydraulic engine mount, focusing on the decoupler action. The proposed model is a simple nonlinear function, which describes the flow resistance in terms of the decoupler plate displacement and speed. The flow resistance using this model increases dramatically as the decoupler plate approaches the top or bottom of the decoupler cage. The advantage of the proposed model over the existing ones is its simplicity. Numerical simulation results show the behavior of the model to be realistic. Approximate closed form solutions have been obtained for the system using the multiple scale perturbation method. Perturbation provides a solution for the mount response at resonance. These results match the intuitive and experimental results available in the literature. [ABSTRACT FROM AUTHOR]

Breast cancer remains a leading cause of cancer-related deaths among women, emphasizing the critical need for early detection and monitoring techniques. Conventional imaging modalities such as mammography, MRI, and ultrasound have face sensitivity, specificity, cost, and patient comfort limitations. This study introduces a handheld Near-Infrared Diffuse Optical Tomography (NIR DOT) probe for breast cancer imaging. The NIRscan probe utilizes multi-wavelength light-emitting diodes (LEDs) and a linear charge-coupled device (CCD) sensor to acquire real-time optical data, reconstructing cross-sectional images of breast tissue based on scattering and absorption coefficients. With wavelengths optimized for the differential optical properties of tissue components, the probe enables functional imaging, distinguishing between healthy and malignant tissues. Clinical evaluations have demonstrated its potential for precise tumor localization and monitoring therapeutic responses, achieving a sensitivity of 94.7% and specificity of 84.2%. By incorporating machine learning algorithms and a modified diffusion equation (MDE), the system enhances the accuracy and speed of image reconstruction, supporting rapid, non-invasive diagnostics. This development represents a significant step forward in portable, cost-effective solutions for breast cancer detection, with potential applications in low-resource settings and diverse clinical environments. [ABSTRACT FROM AUTHOR]

Proposes a mathematical model for the transverse vibration of a plate to be used for free and forced vibration control purposes. Why modal approximations are recommended as the most suitable order reduction method; Poisson-Kirchoff plate theory used to study the transverse vibrations of a rectangular simply supported plate with attached piezoelectric actuators; Optimization of actuator/sensor locations.

Focuses on the El Nino Southern Oscillation (ENSO) a natural physical phenomenon caused by interactions of the ocean and the atmosphere. Discovery of the ENSO; Kevin Wave Hypothesis as explanation to the ENSO; Effects of ENSO-induced climate anomalies; Effects of El Nino to biodiversity; Adoption of policies to anticipate destructive impacts of ENSO. INSET: How El Nino affects biodiversity..

Fungal endophytes were identified associated with leaves, stems and roots of wild grasses (Poaceae) and sedges (Cyperaceae) residing in Hyrcanian Forests, some of the most unique and unspoiled forest systems in the world. The plants grew in two climatically-distinct regions of Golestan and Semnan provinces of Iran. Endophytic fungi isolated from these plants were categorised into 27 morphogroups based on physical attributes measured in vitro. Sequence diversity was estimated from the internal transcribed spacer (ITS) region of the ribosomal DNA gene. Of the 53 isolates characterised in this study, identification of only one isolate was conclusive at the species level. Twenty-eight isolates were identified to the level of genus, belonging to seven families and six orders, six isolates to the level of family, 13 at the level of order, one to the super family, and four to the subphylum. Members of the genera Fusarium and Alternaria, and of the families Necteriaceae, Pleosporaceae and Trichocomaceae were the most abundant fungal endophytes identified. Several endophytes resembled those of fungal pathogens. This study advances our understanding of endophytic fungal communities of indigenous grasses and sedges in Hyrcanian Forests. [ABSTRACT FROM AUTHOR]

This paper provides the analytical and experimental studies into the nonlinear mode coupling in a tuning fork microresonator, with electrostatic actuation at forced and internal resonance frequencies. The analytical investigation leads to modal equations that take into account kinematic and electrostatic nonlinearities. The equations of motion are derived using Lagrange’s energy method. The theoretical resonance curves are determined by using the two-variable expansion perturbation technique near simultaneous subharmonic and internal resonances. The two desired mode shapes of the device are tailored to establish an approximate two-to-one frequency ratio between their natural frequencies. A sample device design is fabricated in a commercial foundry process. The influence of AC driving levels and a detuning parameter, due to inevitable fabrication imperfections, on the system dynamics are investigated theoretically and experimentally. It is shown that the deviation from ideal internal resonance condition separates the region of the nonlinear vibration into two distinct excitation frequencies. The model and simulated results obtained by the perturbation analysis are validated by comparing them with the experimental results. [2017–0297] [ABSTRACT FROM AUTHOR]

This paper reports on the design and characterization of an $H$ -shaped microresonator exhibiting nonlinear modal interactions due to 2:1 internal resonance. This has been made possible through careful design of the structure with attention to the limits of microfabricated devices. The intended nonlinear dynamics rely on the continuous transfer of energy between the anti-phase motions of two $H$ -like proof masses of the device to a mode along the orthogonal direction. Finite element and reduced order models of the structure were developed and used to design the devices with two desired flexural modes in a ~2:1 frequency ratio. The microresonator was fabricated in a commercial foundry process. Extensive experiments and transient simulations were conducted to verify the desired nonlinear responses and the models. It was demonstrated that the low-frequency mode of the device was excited through auto-parametric excitation of the higher frequency mode when the excitation level exceeded a specific threshold as expected. The device design methodologies can be employed to fabricate various sensors, including nonlinear Coriolis vibratory gyroscopes incorporating 2:1 internal resonance. [2017-0035] [ABSTRACT FROM AUTHOR]

Reports on the occurrence of viruses affecting soybeans in Iran. Testing of samples by enzyme-linked immunosorbent assay; Overall virus disease incidence.

Breast cancer patients undergoing neoadjuvant chemotherapy (NAC) require precise and accurate evaluation of treatment response. Residual cancer burden (RCB) is a prognostic tool widely used to estimate survival outcomes in breast cancer. In this study, we introduced a machine-learning-based optical biosensor called the Opti-scan probe to assess residual cancer burden in breast cancer patients undergoing NAC. The Opti-scan probe data were acquired from 15 patients (mean age: 61.8 years) before and after each cycle of NAC. Using regression analysis with k-fold cross-validation, we calculated the optical properties of healthy and unhealthy breast tissues. The ML predictive model was trained on the optical parameter values and breast cancer imaging features obtained from the Opti-scan probe data to calculate RCB values. The results show that the ML model achieved a high accuracy of 0.98 in predicting RCB number/class based on the changes in optical properties measured by the Opti-scan probe. These findings suggest that our ML-based Opti-scan probe has considerable potential as a valuable tool for the assessment of breast cancer response after NAC and to guide treatment decisions. Therefore, it could be a promising, non-invasive, and accurate method for monitoring breast cancer patient's response to NAC. [ABSTRACT FROM AUTHOR]

Formation of membrane pinholes is a common defect in fuel cells, inflicting more cost and making less durable cells. This work focuses on mitigating this issue, and offers a continuous online treatment instead of attempting to dynamically model the hydrogen transfer leak rate. This is achieved by controlling the differential pressure between the anode and cathode compartments at the inlet side of the fuel cell stack, known as the fuel overpressure. The model predictive control approach is used to attain the objectives in a Ballard 9-cell Mk1100 polymer electrolyte membrane fuel cell (PEMFC) with inclusion of hydrogen transfer leak. Furthermore, the pneumatic modeling technique is used to model the entire anode side of a fuel cell station. The hydrogen transfer leak is embedded in the model in a novel way, and is considered as a disturbance during the controller design. Experimental results for different sizes of hydrogen transfer leaks are provided to show the benefits of fuel overpressure control system in alleviating the effects of membrane pinholes, which in turn increases membrane longevity, and reduces hydrogen emissions in the eventual presence of transfer leaks. Moreover, the model predictive controller provides an optimal control input while satisfying the problem constraints. [ABSTRACT FROM AUTHOR]

This paper proposes a mechatronic suspension system with capabilities of energy regeneration and semi-active control [i.e., skyhook (SK)], incorporated into the mechanism. The system overcomes the trade-off between energy consumption and ride handling/comfort in a semi-active/active suspension system. Central to the concept is the development of a switched-mode rectifier (SMR) capable of providing either a positive or negative damping ratio by controlling the electric current to alternate between regenerative and motoring modes. Using the implemented circuit, a regenerative SK control strategy is utilized to provide a continuous variable damping force that significantly improves the vibration isolation. Simulation results are presented to demonstrate power flow in both regenerating and motoring modes by utilizing a current controller. Furthermore, experimental results are presented highlighting performance of the regenerative suspension prototype in terms of power regeneration, sprung mass absolute acceleration, and relative displacement. In addition, both theoretical and experimental power conversion efficiencies in various segments of the mechatronic suspension are analyzed and reported. [ABSTRACT FROM PUBLISHER]

The hydrogen emission rate for a Proton Exchange Membrane fuel cell stack with transfer leaks is characterized. A Ballard 9-cell Mk1100 stack with one internally-leaky cell is employed. The leak is simulated by injecting measured flows of dry hydrogen into the cathode of the middle cell in the stack. It is observed that injecting of enough hydrogen into the cell forces it into oxygen starvation, and then hydrogen emissions appear in the cathode outlet. Extensive experiments are conducted to evaluate individual cell voltages and quantify hydrogen emissions in the cathode exhaust during oxygen-starved conditions for a stack. A hysteresis phenomenon is observed for the emission start points, strongly suggesting that full starvation changes the flow resistance through the affected cell. In parallel, a mathematical model is developed to estimate the amount of hydrogen in the cathode outlet. Simulation results verify the accuracy of the model for estimation of measured hydrogen emission rates in the cathode exhaust. This model can be utilized as an independent indicator of emissions providing redundancy for the cathode exhaust hydrogen sensor, or as an alternative measure where catalytic sensors cannot perform correctly in the lack of proper concentrations of oxygen. [ABSTRACT FROM AUTHOR]

This paper proposes an algorithm to control the suspension dynamics with an energy regeneration capability and high conversion efficiency. Central to the concept is the development of a switched-mode rectifier (SMR) that is capable of providing either an equivalent positive or negative damping and alternating between regenerative and motoring modes. Simulation results are presented to demonstrate power flow in regeneration and motoring modes and verify the equivalent damping characteristic and vibration energy harvesting. The studies are conducted on a small-scale proof-of-concept electromagnetic suspension system excited by emulated International Standard Organization (ISO) 8608 road profiles. An autonomous start/stop algorithm is proposed such that autonomously turns on or off the converter. This mechanism mitigates quiescent power consumption of auxiliary integrated circuits (ICs) such as gate drivers and current transducers, therefore increasing the conversion efficiency of the power electronics throughout an ISO standardized variable-speed driving cycle. The autonomous start/stop algorithm is implemented experimentally to demonstrate its feasibility under typical standardized driving cycles. [ABSTRACT FROM PUBLISHER]

Hydrogen emissions during low oxygen concentration appear in the cathode exhaust of a PEM fuel cell stack. In this paper, the hydrogen emission rates for a stack containing cells without hydrogen crossover leaks are characterized. A Ballard 9-cell Mk1100 stack under standard FCvelocity ® 1 -HD6 bus module operating conditions is employed, and extensive experiments are conducted under current demand to evaluate individual cell voltages and quantify hydrogen emissions. The results indicate that the emission rates are a strong function of current demands. In parallel, a model is developed to estimate the amount of hydrogen in the cathode outlet. To illustrate the accuracy of the developed model, the simulation results and the measured hydrogen emission rates in the cathode exhaust are compared for two current demands. It is acknowledged that the proposed model can be a reliable emulator for the hydrogen sensor in the cathode exhaust, where catalytic sensors cannot perform correctly because of the lack of proper oxygen concentrations, or other types of sensor may fail due to wetting or sensor degradation. Moreover, the proposed model provides a user-friendly tool for systems engineers to design reliable start-up procedures for the control of hydrogen emissions. [ABSTRACT FROM AUTHOR]

In this paper a vehicle suspension system with energy harvesting capability is developed, and an analytical methodology for the optimal design of the system is proposed. The optimization technique provides design guidelines for determining the stiffness and damping coefficients aimed at the optimal performance in terms of ride comfort and energy regeneration. The corresponding performance metrics are selected as root-mean-square (RMS) of sprung mass acceleration and expectation of generated power. The actual road roughness is considered as the stochastic excitation defined by ISO 8608:1995 standard road profiles and used in deriving the optimization method. An electronic circuit is proposed to provide variable damping in the real-time based on the optimization rule. A test-bed is utilized and the experiments under different driving conditions are conducted to verify the effectiveness of the proposed method. The test results suggest that the analytical approach is credible in determining the optimality of system performance. [ABSTRACT FROM AUTHOR]

When hydrogen leaks through holes in membrane-electrode assemblies (MEAs) in proton exchange membrane (PEM) fuel cells, it recombines directly with air. This recombination results in a reduction in oxygen concentration on the cathode side of the MEA. In this paper, the signatures of electrochemical impedance spectroscopy (EIS) are analyzed in different multi-cell stack configurations to show the relation between hydrogen leak rate and reduced oxygen concentrations. The reduction in concentration was made by mixing oxygen with nitrogen at different rates, and the increase in hydrogen leak rate was made by controlling the differential pressure (dP) between anode and cathode. To analyze the impedance signatures, we fit the data of oxygen concentration and dP with the parameters of a Randles circuit. The correlation between the parameters of the two data sets allows us to understand the change in impedance signatures with respect to reduction of oxygen in the cathode side. To have a better insight on the effect of insufficient oxygen at the cathode, a model that establishes a relationship between impedance and voltage was considered. Using this model along with the impedance signatures we were able to detect the reduction of oxygen concentrations at the cathode with the help of fuzzy rule-base. However, resolution of detection was reduced with the reduction of leak rate and/or increases in the stack cell count. [ABSTRACT FROM AUTHOR]

When hydrogen leaks through holes or cracks in membrane-electrode assemblies (MEAs) in Proton Exchange Membrane (PEM) fuel cells, it recombines directly with air. This recombination results in a reduction in oxygen concentration on the cathode side of the MEA. In this paper, the signatures of electrochemical impedance spectroscopy (EIS) are analyzed in different multi-cell stack configurations to show the relation between hydrogen leak rate and reduced oxygen concentrations. The reduction in concentration was made by mixing oxygen with nitrogen at different rates, and the increase in hydrogen leak rate was made by controlling the differential pressure (dP) between anode and cathode. To analyze the impedance signatures, we fit the data of oxygen concentration and dP with the parameters of a Randles circuit. The correlation between the parameters of the two data sets allows us to understand the change in impedance signatures with respect to reduction of oxygen in the cathode side. To have a better insight on the effect of insufficient oxygen at the cathode, a model that establishes a relationship between impedance and voltage was considered. Using this model along with the impedance signatures we were able to detect the reduction of oxygen concentrations at the cathode with the help of fuzzy rule-base. However, resolution of detection was reduced with the reduction of leak rate and/or increases in the stack cell count. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of a modified conventional solenoid valve as a low-cost controllable reciprocating force actuator. The applied modifications include adding a spring for plunger return mechanism, applying a bias current for pre-compression of the spring, and minor machining of the plunger rod. Potentially, this actuator can be employed in many applications, e.g. active noise and vibration control systems. A mathematical model of the actuator is given using the fundamental electromagnetic relationships. This model identifies the transfer function between the applied current and the output force. An experimental analysis in the frequency domain is conducted to obtain the current/force transfer function and validate the mathematical model. It is shown that in the stroke range of interest, the nonlinear analytical model of this actuator can be well estimated by a linear model. To investigate the performance of the actuator in a real application, this actuator is installed and tested in an active engine mount prototype. The analytical model of this engine mount is modified to include the actuator. The simulation result indicates that the stiffness and damping of this mount is tunable by controlling the input current to the actuator. The experimental results are also in close agreement with the simulations. [ABSTRACT FROM PUBLISHER]

This paper describes the design of a versatile and fully controllable active engine mount. The proposed active mount is capable of addressing vibration isolation requirements at various driving conditions. This design addresses a better ride quality that has always been demanded by the automotive industry, as well as satisfying sophisticated vibration isolation requirements for the unconventional engines, i.e. variable displacement, and hybrids. The proposed engine mount replaces the decoupler of the original design with a solenoid actuator. The mathematical model of the active mount is obtained. The dynamic characteristics of the mount are shown to be highly controllable over the operating frequency range of excitation in engines. The effectiveness of the developed active engine mount for various working conditions of engine is also evaluated. Several driving conditions are investigated and proper control strategies are utilized to demonstrate the mount's capability to fulfill the isolation requirements for each condition. The promising results, in addition to compactness, low cost, fail safety, and durability are the main advantages of the proposed active engine mount, which makes it viable for automotive applications. [ABSTRACT FROM PUBLISHER]