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Free-hand palpation ultrasound elastography is a noninvasive approach for detecting pathological alteration in tissue. In this method, the tissue is compressed by a handheld probe and displacement of each sample is estimated, a process which is also known as time-delay estimation (TDE). Even with the simplifying assumption that ignores out of plane motion, TDE is an ill-posed problem requiring estimation of axial and lateral displacements for each sample from its intensity. A well-known class of methods for making elastography a well-posed problem is regularized optimization-based methods, which imposes smoothness regularization in the associated cost function. In this article, we propose to utilize channel data that have been compensated for time gain and time delay (introduced by transmission) instead of postbeamformed radio frequency (RF) data in the optimization problem. We name our proposed method Channel data for GLobal Ultrasound Elastography (CGLUE). We analytically derive bias and variances of TDE as functions of data noise for CGLUE and Global Ultrasound Elastography (GLUE) and use the Cauchy–Schwarz inequality to prove that CGLUE provides a TDE with lower bias and variance error. To further illustrate the improved performance of CGLUE, the results of simulation, experimental phantom, and ex-vivo experiments are presented.

The prevalence of aflatoxins (AFB1) in Iranian wheat flours was determined by immunoaffinity chromatography (HPLC). A total of 180 wheat flour and 60 wheat bran samples including three types of flo...

Ultrasound elastography is an emerging noninvasive imaging technique wherein pathological alterations can be visualized by revealing the mechanical properties of the tissue. Estimating tissue displacement in all directions is required to accurately estimate the mechanical properties. Despite capabilities of elastography techniques in estimating displacement in both axial and lateral directions, estimation of axial displacement is more accurate than lateral direction due to higher sampling frequency, higher resolution and having a carrier signal propagating in the axial direction. Among different ultrasound imaging techniques, Synthetic Aperture (SA) has better lateral resolution than others, but it is not commonly used for ultrasound elastography due to its limitation in imaging depth of field. Virtual source synthetic aperture (VSSA) imaging is a technique to implement synthetic aperture beamforming on the focused transmitted data to overcome limitation of SA in depth of field while maintaining the same lateral resolution as SA. Besides lateral resolution, VSSA has the capability of increasing sampling frequency in the lateral direction without interpolation. In this paper, we utilize VSSA to perform beamforming to enable higher resolution and sampling frequency in the lateral direction. The beamformed data is then processed using our recently published elastography technique, OVERWIND [1]. Simulation and experimental results show substantial improvement in estimation of lateral displacements., 9 pages, 8 figures

Ultrasound elastography is a non-invasive technique for detecting pathological alterations in tissue. It is known that pathological alteration of tissue often has a direct impact on its elastic modulus, which can be revealed using elastography. For estimating elastic modulus, we need to estimate both axial and lateral displacement accurately. Current state of the art elastography techniques provide a substantially less accurate lateral displacement field as compared to the axial displacement field. One of the most important factors in poor lateral estimation is a low sampling frequency in the lateral direction. In this paper, we use synthetic aperture beamforming to benefit from its capability of high sampling frequency in the lateral direction. We compare highly sampled data and focused line per line beam formed data by feeding them to our recently published elastography method, OVERWIND [1]. According to simulation and phantom experiments, not only the lateral displacement estimation is substantially improved, but also the axial displacement estimation is improved.

In the present work, cylindrical shape 316 L cellular structure with different densities in its core and outer layer (shell) is fabricated by using carbamide as a space holder, via powder metallurgy route and layer-by-layer technique. The arrangement of the created pore is the same as face-centered cubic atomic structure, and different densities are created in two regions by using carbamide particles having two different sizes in the range of 1.7-2 and 2-2.4 mm. The effect of creating a structure with higher porosity (64.5%) in the core and lower porosity (53.8%) in the shell and vice versa and also change in the ratio of the core to the cylinder cross-sectional areas, on the mechanical properties and compaction load bearing of the fabricated foam samples were investigated. In leaching process of the carbamide particles, as an important step of porous structure’s fabrication, it is shown that discontinuous leaching process is more favorable than continuous, by which it would be possible to remove more carbamide particles (around 20%) at the same time. Furthermore, the deformation of the density-graded foam shows the parallel mechanism in the core and shell sections, and the contribution of each part depends on its density and thickness. The energy absorption behavior of the fabricated specimens is evaluated optimally in terms of the energy absorption value associated with the ideal adsorption behavior. The maximum ideal energy absorption efficiency for the samples with more porosity in the shell was approximately equal to 0.91, while for the sample includes the lower amount of porosity in the shell, this value was in the range of 0.85 and 0.89.

In this study, double-layer structured 316L stainless steel foam is fabricated through a layer by layer space holder method. The fabricated foams contain uniform pore distribution and can be categorized as body centered cubic crystal structures. Each sample is made of two layers in the axial direction. To induce 51 vol.% and 62 vol.% porosity in the first and the second layers, 1.7 to 2.0 mm and 2.0 to 2.4 mm spherical carbamide particles are used, respectively. In this study, the effect of the height of each layer on the compressive behavior of the fabricated foams is investigated in detail. The results indicate that compressive deformation of the double-layered foams starts from the high porosity (62 vol.%) layer and then shifts to the low porosity (51 vol.%) layer. Deformation of the double-layered 316L foams demonstrates two plateau regions, whose lengths depend on the heights of the low and high porosity layers.

Introduction: Organophosphorus compounds are frequently used as pesticides and insecticides in agriculture, livestock and home. Because of the high toxicity, it seems is very important its removal from the environment. An enzyme called organophosphorus hydrolase (OPH) is responsible for the decomposition of organophosphorus compounds in most of the strains. Production of enzymes and strains with more efficiency is frequently performed by genetic engineering techniques. Materials and Methods: In this study, we used PCR-based method for quick and easy improvement in activity of OPH enzyme. We selected 5.5 mM Mg2+ and 0.2 mM and Mn2+ concentrations for high PCR product. Results: After one round of error prone PCR (epPCR), The 5 number of screened strains (29%) were shown more ability than the native strains to degrade of diazinon, with more than 25% raising ratio. The E6 strain was found to have highest improvement degradation, with 29.3% improvement. At 48-hour time point, the E6 strains were able to completely remove of diazinon. Conclusions: The epPCR method has the low complexity than other methods and can provide a diverse library include efficient mutants.

Herein, various morphologies of AlOOH (boehmite) nanostructures were successfully synthesized via a facile hydrothermal route. The obtained AlOOH nanostructures were utilized as a novel starting reagent with AgNO3 and cochineal powder for synthesizing Ag–Al2O3 nanocomposites via a thermal decomposition method. The prepared nanocomposites were applied as photocatalyst for decolorization of acid violet 7 as an azo dye under visible light irradiation. The results showed the rice-like sample (A3) has the highest photodegradation efficiency due to its more surface to volume ratio. Moreover, the synthesized AlOOH nanostructures were directly calcined to transform into rice-like Al2O3 nanostructures as an adsorbent for Pb2+ ions removing from aqueous medium. The rice-like Al2O3 (sample B3) as an adsorbent showed a remarkable adsorption capacity (250 mg/g) compared to other samples with different morphologies.

In the present work, a new technique for creating uniform distributed space holder is used for producing porous 316 L stainless steel foam. Uniform pore distribution with Face-Centered Cubic (FCC) packing is created by a novel method using spherical carbamide as a space holder. The specimens have maximum porosity about 71.5% after sintering at 1200 °C for 60 min in N2 atmosphere. The microstructure of the metal foams, cell size and shape was studied using optical microscopy and Clemex Vision PE commercial image-analyzer software. The compression test was used to evaluate the mechanical properties of the foam samples. The results showed that uniform pore distribution can improve elastic properties and compressive strength. Keywords: Powder metallurgy, Porous material, Space holder technique, 316 L stainless steel

This paper introduces a novel technique to estimate tissue displacement in quasi-static elastography. A major challenge in elastography is estimation of displacement (also referred to time-delay estimation) between pre-compressed and post-compressed ultrasound data. Maximizing normalized cross correlation (NCC) of ultrasound radio-frequency (RF) data of the pre- and post-compressed images is a popular technique for strain estimation due to its simplicity and computational efficiency. Several papers have been published to increase the accuracy and quality of displacement estimation based on NCC. All of these methods use 2D spatial windows in RF data to estimate NCC, wherein displacement is assumed to be constant within each window. In this work, we extend this assumption along the third dimension. Two approaches are proposed to get third dimension. In the first approach, we use temporal domain to exploit neighboring samples in both spatial and temporal directions. Considering temporal information is important since traditional and ultrafast ultrasound machines are, respectively, capable of imaging at more than 30 frame per second (fps) and 1000 fps. Another approach is to use time-delayed pre-beam formed data (channel data) instead of RF data. In this method information of all channels that are recorded as pre-beam formed data of each RF line will be considered as 3rd dimension. We call these methods as spatial temporal normalized cross correlation (STNCC) and channel data normalized cross correlation (CNCC) and show that they substantially outperforms NCC using simulation, phantom and in-vivo experiments. Given substantial improvements of results in addition to the relative simplicity of implementing STNCC and CNCC, the proposed approaches can potentially have a large impact in both academic and commercial work on ultrasound elastography.

Ficin (EC 3.4.22.3), a cysteine endoproteolytic protease in fig trees' latex, has multiple isoforms. Until now, no data on autolysis of individual ficins (ficin isoforms) are available. Following purification, ficins' autolysis was determined by HPLC chromatogram changes and ultrafiltrations at different temperatures and storage times. These results showed that the number of HPLC peaks in latex proteins purification of Ficus carica cv. Sabz varied from previous fig varieties or cultivars. Proteolytic activity of ficins was inhibited by specific cysteine protease inhibitors, confirming the participation of the cysteine residue in the active site. The zeta potential of the first two eluted peaks (I and II) was negative, while that of other peaks were positive. All ficins were susceptible to autolysis when stored at high temperatures. In contrast, only the last two ficins (B, C) were prone to autolysis at cold temperature after long storage period. The rate of degradation of the ficins was significantly increased with the increased storage time. The ficin (A) related to peak (III) had the highest and the lowest surface hydrophobic patches and ratio of autolytic to proteolytic activity, respectively.

A distributed robust consensus of multiple autonomous underactuated surface vessels (AUSV) is studied in the presence of unknown environmental disturbances. The vehicles have 3 degrees of freedom and two actuators. Since the actuated and unactuated states of the vehicles are strongly coupled, first their kinematics and dynamics are transformed to a cascade non-linear system. Then, based on the properties of non-linear cascade systems, a state-based switching controller is proposed which guarantees the robust consensus of AUSVs. To illustrate the performance of the proposed consensus approach, simulation results are provided. This publication was made possible by NPRP Grant no. NPRP 5-045-2-017 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors. Scopus

Cesium and mercury are two mono-valent elements which can be found in toxic industrial, medical, and nuclear wastes. Their presence in the environment has deleterious effects on the ecosystem, living organisms including humans. Due to the chemical nature of these metals, bioremediation by conventional methods is more difficult to achieve compared to other metals. In this study, we used three biosorbents (oak powder, gall nut, and bacterial exopolymer) for the bioremediation of Hg and Cs. Bio-polymer was produced in the GMS mineral broth. Synthetic wastes of Hg(NO3)2 and isotope Cs-133 as the single-metal solutions were used. The biorefining process was carried out in glass columns, made of Pyrex, with dimensions 20 × 7/2 cm2 with a V-shaped bottom. The samples were analyzed using atomic absorption. The experimental results showed that eliminated metal percent by oak powder, gall nut, and bacterial exopolymer were, respectively, of 94.8%, 96%, and 13.8% for Hg and 7.8%, 4.4%, and 69.4% for Cs. The tests re...

In this study, open cell Al–Al2O3 composite foams having different volume fractions of Al2O3 (0–10 vol.%) were synthesized by using the space-holder technique. Various amounts of spherical carbamide particles with mean size of 1.2 mm were used for producing porosity fractions of 50, 60 and 70 vol.%. Compression test was performed on the foam samples for evaluating the compressive properties and energy absorption behavior of them. The results showed that the compressive properties and energy absorption behavior depend on the volume fraction of Al2O3 and porosity fraction. Generally, by decreasing the porosity fraction, the energy absorption capacity and compressive properties were raised. The composite foams containing 2 vol.% Al2O3 showed superior compressive properties and energy absorption behavior in contrast to other foams studied in this work. Also it was found, as the strain during the compression test is increased, the energy absorption capacity is increased too. It is noticeable that, the slope of energy absorption capacity–strain curves decreases by increasing the porosity fraction.

Recombinant Escherichia coli displaying organophosphorus hydrolase (OPH) was used to overcome the diffusion barrier limitation of organophosphorus pesticides. A new anchor system derived from the N-terminal domain of ice-nucleation protein from Pseudomonas syringae InaV (InaV-N) was used to display OPH onto the surface. The designed sequence was cloned in the vector pET-28a(+) and then was expressed in E. coli. Tracing of the expression location of the recombinant protein using SDS-PAGE showed the presentation of OPH by InaV-N on the outer membrane, and the ability of recombinant E. coli to utilize diazinon as the sole source of energy, without growth inhibition, indicated its significant activity. The location of OPH was detected by comparing the activity of the outer membrane fraction with the inner membrane and cytoplasm fractions. Studies revealed that recombinant E. coli can degrade 50% of 2 mM chlorpyrifos in 2 min. It can be concluded that InaV-N can be used efficiently to display foreign functional protein, and these results highlight the high potential of an engineered bacterium to be used in bioremediation of pesticide-contaminated sources in the environment.

In this paper, we discus about production Hydrogen for industrial and laboratories. We will discuss about methods of production Hydrogen and exquisite in electrolysis Power Acids. In this paper, compare some methods and materials. We prefer Sulfuric Acid. For electrolysis Sulfuric Acid, we need electrode. The material of electrode must refractory in corrosion by Sulfuric Acid. This material is alloy from palatine and other material. The physical face of electrode is too important and discus in this paper.

In this paper, robust distributed consensus of autonomous underwater vehicles (AUV) in the presence of ocean disturbances is investigated where the considered model describes both the kinematics and dynamics of the AUV with six degrees of freedom. The backstepping technique is used to make the position and the orientation of the vehicles to reach a consensus. This is achieved in two steps. First the desired linear and angular velocities for position and orientation consensus are calculated. Then the control torques are designed to force the vehicle velocities to converge to the desired ones obtained in the first step in the presence of environmental disturbances. To illustrate the performance of the proposed consensus approaches, simulation results are provided. This publication was made possible by NPRP grant No. NPRP 5-045-2-017 from the Qatar National Research Fund (a member of Qatar Foundation). Scopus

Ice nucleation proteins (INP) are a major cause of frost damage in plants and crops. Here, an INP gene from Fusarium acuminatum was optimized, synthesized, expressed in E.coli and subsequently purified and characterized. The protein belongs to the second class of ice nucleation proteins with an optimum pH 5.5, relative activity and stability between pH 5 and 9.5 and up to 45 °C. The protein was fully active and stable in the presence of dimethyl sulfoxide (DMSO), dioxane, acetone and ethyl acetate. Moreover, it retained over 50 % of its original activity in the presence of polyvinyl alcohol. The 3D structure model of the INP-F indicated the protein had three distinct domains as exist in other ice nucleation proteins with some variations. Considering these promising results, INP-F could be a novel candidate for industrial applications.

In Iranian traditional medicine, different species of the genus Tetrataenium are used as antiseptic, spice and food additives.The present study examined the possible antioxidant effects of hydro-alcoholic extracts of different parts of Tetrataenium lasiopetalum (Boiss.) Manden (Apiaceae).Laminas, stems, petioles, fruits, peduncles and flowers of T. lasiopetalum were collected, dried and then extracted by ethanol and water (70:30). Antioxidant activities of extracts were examined by employing different in vitro assays, i.e., 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, metal chelating, reducing power activities and hemoglobin-induced linoleic acid system. Also, total phenolic and flavonoid contents of the extracts were evaluated.Hydro-alcoholic extract of T. lasiopetalum flower showed the highest activity in scavenging of DPPH (IC50 = 170 ± 7 μg/mL). In metal chelating assay, lamina extract possesses a better iron ion chelating activity than other extracts (230 ± 10 μg/mL). Lamina hydro-alcoholic extract demonstrated better activity in reducing the power and hemoglobin-induced linoleic acid system than other parts of T. lasiopetalum.These results showed the antioxidant activity of different parts of T. lasiopetalum based on its usage in traditional medicine.

Methyl-3-O-methyl gallate (M3OMG) is a rare natural product that showed promising in vitro antioxidant activities. In this study, the protective role of synthetic M3OMG against sodium fluoride (NaF)-induced oxidative stress in rat brain was evaluated. Animals were treated with either M3OMG (10 and 20 mg/kg i.p.), vitamin C (10 mg/kg i.p.) as the standard antioxidant or the vehicle (5 % dimethyl sulfoxide; 1 ml/kg) for 1 week. Oxidative stress was induced in the brain by adding 600 ppm NaF in the drinking water for 7 days. At the end of the treatment period, the levels of thiobarbituric acid reactive substances (TBARS), reduced glutathione and the activities of antioxidant enzymes (superoxide dismutase and catalase) were evaluated in brain homogenates. M3OMG treatment mitigated the NaF-induced oxidative stress through normalization of the level of TBARS, reduced levels of glutathione and by the restoration of the diminished antioxidant enzyme activities. In conclusion, M3OMG could have a potential for treating neurotoxicity induced by fluoride or related environmental pollutants.

Quercetin is a well known aglycone flavonoid that is widely found in different food sources.In this study, the in vivo neuroprotective potential of quercetin against sodium fluoride-induced oxidative stress was evaluated.Wistar rats were divided into five treatment groups and then subjected to daily intraperitoneally treatment with quercetin (at 10 and 20 mg/kg body weight), vitamin C (at 10 mg/kg), or vehicle. After a 1 week treatment period, all groups except saline treated (normal group), were intoxicated with sodium fluoride (NaF) for 1 week. Rat brains were then removed and homogenized for measurement of antioxidant markers including superoxide dismutase (SOD), reduced glutathione, catalase, and lipid peroxidation final products.The thiobarbituric acid reactive substances (TBARS) levels in the heart homogenate of sodium fluoride treated rats (42.04 ± 2.14 nmol MDA eq/g tissue) increased compared to the normal rats (35.99 ± 1.08 nmol MDA eq/g tissue). Animals which were pretreated with quercetin at 20 mg/kg for 1 week prior to sodium fluoride intoxication showed significant reduction in the TBARS level (36.13 ± 1.12 nmol MDA eq/g tissue). Also, pretreatment with quercetin (20 mg/kg) restored the SOD and catalase activities and modified the level of reduced glutathione compared with the control group (p0.05).The present study revealed a potent neuroprotective potential of quercetin against NaF-induced toxicity.

Several strains of bacteria were successfully isolated from effluent storage pools of factories producing pesticides and from soil moisture around them. The isolates were capable of utilizing chlorpyrifos (Cp) as the sole source of carbon, phosphorus and energy. Isolates were identified based on16SrRNA sequence analysis and were named IRLM.1, IRLM.2, IRLM.3, IRLM.4, and IRLM.5. IRLM.1 was able to grow at concentrations of chlorpyrifos up to 2000 mg/L and was selected as a preferable isolate for further analysis. The amount of the degraded Cp and the amount of metabolite 3,5,6-trichloropyridinol (TCP) produced were assessed in IRLM.1 by using high performance liquid chromatography (HPLC) techniques. Additionally, the location of the chlorpyrifos-degrading enzyme was determined by comparing the activity of intact bacteria to cytoplasm activity. Our study reveals that Cp-degrading enzyme of IRLM.1 is cytoplasmic and 10 μl cytoplasm isolated from 0.05 g dry-weight bacteria can degrade 50% of 2 mM Cp in 2 min. Furthermore, the HPLC analysis showed accumulation of TCP in the medium, revealing that IRLM.1 was able to degrade Cp without being affected by the antimicrobial activity of TCP. Moreover, results show that the IRLM.1 isolate could grow and utilize diazinon and malathion as the sole source of carbon, phosphorus and energy. Thus IRLM.1 can successfully participate in efficient degradation of organophosphorus compounds (OPs). Key words: Biodegradation, organophosphorus pesticides, chlorpyrifos, isolation.

This study aim to evaluate the protective effect of silymarin on sodium fluoride-induced oxidative stress in rat cardiac tissues. Animals were pretreated with silymarin at 20 and 10 mg/kg prior to sodium fluoride consumption (600 ppm through drinking water). Vitamin C at 10 mg/kg was used as standard antioxidant. There was a significant increase in thiobarbituric acid reactive substances level (59.36 ± 2.19 nmol MDA eq/g tissue) along with a decrease in antioxidant enzymes activity (64.27 ± 1.98 U/g tissue for superoxide dismutase activity and 29.17 ± 1.01 µmol/min/mg protein for catalase activity) and reduced glutathione level (3.8 ± 0.15 µg/mg protein) in the tissues homogenates of the sodium fluoride-intoxicated rats. Silymarin administration to animals before sodium fluoride consumption modified the levels of biochemical parameters.Este estudo objetiva avaliar o efeito protetor da silimarina em fluoreto de sódio induzida por estresse oxidativo em tecido cardíaco de ratos. Os animais foram pré-tratados com silimarina a 20 e 10 mg/kg antes do consumo de fluoreto de sódio (600 ppm através da água de beber). A vitamina C a 10 mg/kg foi utilizada como antioxidante padrão. Houve um aumento significativo no nível de substâncias tiobarbitúrico reativo de ácido (59,36 ± 2.19 nmol MDA eq/g tecido), juntamente com uma diminuição da atividade de enzimas antioxidantes (64,27 ± 1,98 U/g tecido para a atividade de superóxido dismutase e 29,7 ± 1,01 mmol/min/mg de proteína para a atividade da catalase) e nível de glutationa reduzida (3,8 ± 0,15 mg/mg de proteína) nos homogeneizados de tecidos dos fluoreto de sódio-intoxicados ratos. Administração de silimarina a animais, antes do consumo de fluoreto de sódio modifou os níveis de parâmetros bioquímicos.

The antioxidative and cardioprotective properties of quercetin were investigated against sodium fluoride (NaF) induced oxidative stress in rat hearts. Experimental rats were divided into five groups. The first group served as the untreated (normal) control. The second group received NaF at a dose of 600 ppm through drinking water for 1 week, and served as the toxin control. The third and fourth groups were exposed to quercetin (at the dose of 10 and 20 mg kg(-1) intraperitoneally (i.p.) for 1 week) prior to NaF intoxication, and the fifth group was treated with vitamin C at a dose of 10 mg kg(-1) i.p., for 1 week prior to NaF intoxication and served as the positive control in the study. The activities of various antioxidant enzymes, superoxide dismutase and catalase, level of reduced glutathione and lipid peroxidation end product were determined in the cardiac tissues of all the experimental animals. NaF intoxication significantly altered all the indices related to the pro-oxidant-antioxidant status of the heart; treatment with the active constituents prior to NaF administration, however, prevented these alterations. The combined results suggest that quercetin protects rat hearts from NaF-induced oxidative stress, probably via its antioxidant properties.