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In the continuous scaling-up process of the separating system, a mechanism exists that transforms the behavior of the flow field, resulting in deviations from the original model and conclusions. The paper examined the effects of the scale up of a fluidized bed by CFD. It was observed that increasing the diameter reduces the amplitude of axial density fluctuations. Similarly, increasing the static height increases the amplitude. Moreover, increasing the static bed height enhances the visibility of the cyclic flow structure of gas and solid phases. The flow structure in large bed diameters is disrupted. The impact of changing the bed diameter on bed density is more significant than the static height. As the bed diameter increases, the bubble disturbance decreases and the aggregation phase gradually disappears while the proportion of the emulsified phase keeps increasing. This study will guide and assist in the future application of separated fluidized beds in industry. [ABSTRACT FROM AUTHOR]

Introduction The clinical presentation of a case as cerebral malaria with molecular identification confirming it as Plasmodium vivax underlines the importance of using molecular tools to identify the species and type of malaria. The possibility of the relationship between the complication observed during clinical diagnosis and the multifactorial molecular changes could likely be the reason for terming it cerebral malaria. Methods We report four cases analyzed using the quantitative buffy coat technique followed by classical Giemsa stained thick-film microscopy, and nested polymerase chain reaction for the genus-specific region of Plasmodium targeting 18S rDNA followed by species-specific identification with a different set of primers and products confirmation with sequencing. Results Primers targeting P. knowlesi generated the expected product size of 153 base pairs that, upon sequencing, matched with the P. vivax sequence reflecting the relatedness of the species. Likewise, primers targeting P. ovale generated a 456 product whose sequence matched the P. vivax sequence. Conclusion Infection with P. vivax can potentially cause cerebral malaria, and P. vivax can cause severe malaria complications alone or mixed with other species and can show cerebral malaria signs, which are typically associated with P. falciparum infections. The sequence relatedness reflects the genome similarity between P. knowlesi and P. ovale with P. vivax. The need to reconfirm with an additional set of newly reported primers is mandatory. [ABSTRACT FROM AUTHOR]

A solid formulation of the pesticide TFM (4-nitro-3-(trifluoromethyl)-phenol) was developed in the 1980s for application in small tributaries during treatments to control invasive sea lamprey (Petromyzon marinus Linnaeus, 1758). Several initial inert ingredients were discontinued and substituted, culminating with an interim formulation that unacceptably softens and rapidly decays in warm conditions. A new TFM bar formulation was developed to resolve poor thermal stability and it was registered with the U.S. Environmental Protection Agency and Health Canada Pesticide Management Regulatory Agency in 2020. Laboratory studies compared the thermostability and dissolution (i.e., TFM release) of the interim and new formulation of TFM bars that were held at 20 °C or 45 °C for 24 hours prior to evaluation. Field tests compared the dissolution of the interim and new formulation of TFM bars when applied in three small tributaries in Michigan. Laboratory tests show that the new formulation bars remain usable when held at 45 °C for 24 hours; whereas, the interim formulation bars partially liquify and are not usable. Field tests indicate the new formulation bars have superior characteristics including a near consistent release of TFM for 10-13 hours when applied in waters with a velocity of < 0.06 m/sec. A near consistent release of TFM was observed for a maximum of about 6 hours in one field application of the interim formulation bars. Water temperature and water velocity influenced both formulations; however, the greatest effects were observed with interim formulation bars where higher initial TFM concentrations were followed by precipitous TFM concentration decreases in tributaries with the highest water temperature or velocity. Field treatment applications will provide data for refining application parameters such as the number of bars required per unit discharge at various water temperatures and the acceptable water velocity range for applications. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Faculty of Pharmacy of Ankara University / Ankara Üniversitesi Eczacilik Fakültesi Dergisi is the property of Ankara University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Malaria is a global threat and a never-ending battle without appropriate identification and differentiation of the parasite species. This work compared the diagnostic methods including the thick film microscopy technique, quantitative buffy coat, and polymerase chain reaction. The inaccuracy of species determination by microscopy and the consequent treatment regime underlines the necessity to upgrade routine diagnostic methods with molecular techniques. In the study, 436 samples were collected; venous blood was processed for the quantitative buffy coat technique followed by classical Giemsa staining of thin and thick smears and nested Polymerase Chain Reaction (nPCR) for the genusspecific region of Plasmodium targeting 18S rDNA followed by species-specific identification. Of 436 samples screened for malaria, results in PCR showed 78.7% (100/127) to be P. vivax, 4.8% (6/127) as P. falciparum and 16.5% (21/127) to be mixed infection (P. vivax + P. falciparum). The prevalence of malaria was 0.29, and there was good concordance between the methods for detecting Plasmodium (Kappa:0.77). In our investigation, nested PCR and TFM exhibited a sensitivity of 97.7% and a specificity of 100% for malaria detection compared to QBC. Clinical parameters- thrombocytopenia and anemia, were compared in this study. A positive association was observed between thrombocytopenia and malaria (p<0.05), but the association between anemia and malaria infection remains unclear. Primer cross-reactions were also observed in the primer sequence of P. ovale and P. knowlesi, but sequencing confirmed it as P. vivax and the study of phylogeny paved a new way in analyzing the relatedness of the sequences. [ABSTRACT FROM AUTHOR]

Drag force models are one of the most important factors that can affect TFM and CFD-DEM simulation results of two-phase systems. This article investigates the accuracies, implementation issues and limitations of the majority of the drag models for spherical, non-spherical and systems with size distribution and evaluates their performance in various simulations. Around 1888 data points were collected from 19 different sources to evaluate the drag force closures on mono-dispersed spherical particles. The Reynolds number and fluid volume fraction ranges were between 0.01 and 10,000 and between 0.33 and 1, respectively. In addition, 776 data points were collected from seven different sources to evaluate the drag force closures on poly-dispersed spherical particles. The Reynolds numbers were between 0.01 and 500, fluid volume fractions between 0.33 and 0.9, and diameter ratios up to 10. A comprehensive discussion on the accuracy and application of these models is given in the article. [ABSTRACT FROM AUTHOR]

Multi-cycle large-eddy simulations (LES) are performed to investigate combustion cycle-to-cycle variability (CCV) in a gasoline spark ignited optical access engine operating under homogeneous stoichiometric conditions. Combustion is addressed with the Thickened Flame Model (TFM) and finite rate chemistry is accounted for through a reduced oxidation reaction mechanism. In view of the fact that computational costs of LES engine simulations are still very high today, this work investigates the use of adaptive mesh refinement (AMR) in the flame zone in conjunction with the artificial flame thickening applied by the TFM model. The paper discusses how the resulting coupled TFM-AMR combustion model allows good resolution of the flame, maintaining accuracy at acceptable costs. First, the details of the coupled model are presented and the effects of the parameters are explored, highlighting their impact on the combustion prediction. Then, computational fluid dynamics (CFD) simulation results are validated against experimental data collected in a low-speed low-load engine point, by comparing 20 LES cycles and 100 measured cycles, for mass fraction burned, combustion phasing, flame images and CCV indices. Lastly, a detailed investigation on the fastest and slowest numerical cycles is presented, analyzing instantaneous flame structures, ignition behaviors, propagation speeds, and probability density function (PDF) of the instantaneous velocity fluctuation around the spark region. The results show that combustion variability is highly correlated to the resolved velocity field and the resolved turbulence intensity, which is found to be the main cause of CCV and affects the early flame kernel growth. This work is an early attempt to use TFM-AMR combustion model for LES simulations of internal combustion engines. [ABSTRACT FROM AUTHOR]

The transverse flux motor (TFM) is an ideal choice for direct drive high torque applications owing to its proven higher torque density compared to the radial flux and axial flux motors. TFM motors have several merits to be used for spacecraft applications, considering the everlasting demand of the industry for reduction in power and mass. This paper investigates the various cogging torque mitigation techniques for transverse flux motor to be effectively used as the drive motor for precise position control spacecraft requirement. The paper discusses the basic design variables of surface mounted TFM (SM-TFM) that are to be considered for minimizing the cogging torque. The effectiveness of cogging torque mitigation techniques are presented for two cases of SM-TFM, one with maximum cogging torque and the other with minimum cogging torque. The different torque ripple minimization techniques studied include skewing of rotor poles, notching of the stator poles, introduction of asymmetry in the stator structure, provision of wedges by the side of poles, segmentation of the magnets and introduction of shunt. The effectiveness of these cogging torque mitigation techniques is studied on two hardware variants of the TFM, one with the modified stator having shunt and the other with the modified rotor having low remanence permanent magnet. The TFM with a shunted stator is effective in torque ripple reduction in addition to the improvements in electromagnetic torque. [ABSTRACT FROM AUTHOR]

The toxic unit and additive index approaches were used to understand how 2 pesticides, 3‐trifluoromethyl‐4‐nitrophenol (TFM) and 2,5‐dichloro‐4‐nitrosalicylanilide (niclosamide; Nic), interact in mixtures. Our first objective was to determine whether the interaction was strictly additive or greater than additive at doses comparable to those used to control invasive sea lamprey (Petromyzon marinus) in the Laurentian Great Lakes, and our second was to compare the utility of the toxic unit and additive index models for determining how TFM and Nic interacted. Typically, TFM is mixed with Nic (1–2%, w/v) to increase its potency and reduce TFM use. However, there is little information on how the 2 chemicals interact. Using a well‐studied, resident nontarget fish, the rainbow trout (Oncorhynchus mykiss), we conducted toxicity tests with TFM, Nic, and TFM:Nic (100:1, w/v; TFM/1% Nic) mixtures over 12 h to determine if the interaction was strictly additive, less than additive (antagonistic), or greater than additive (synergistic). The toxic unit and additive index approaches indicated synergistic interactions at environmentally relevant concentrations, suggesting that both are valid approaches for predicting how TFM and Nic interact. The toxic unit approach was simpler to conceptualize and to calculate, and we recommend that it be used when describing how TFM and Nic, and other similar organic compounds, interact with each other in aquatic ecosystems. Environ Toxicol Chem 2021;40:1419–1430. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Nowadays, thermal cameras play a major role because of its temperature-based photography in many applications such as video surveillance, monitoring electronics/electrical machines, forest monitoring, monitoring babies/adult patients, and suspicious object detection. Tracking pedestrians in thermal video is a major task for such applications. Thermal cameras usually create images based on temperature emitted by the object only and not on the lighting conditions and outdoor environment conditions. But still thermal images have constraints like no texture or colour information, more number of dead pixels, low resolution, and noticeable visual colour patterns in case of any temperature variations. So the challenge in tracking pedestrians in thermal videos is tracking objects/pedestrians throughout the video without an identity switch by overcoming these constraints which may mislead the tracking process. To overcome these constraints, the proposed system uses tri feature matrix (TFM) as an object descriptor which is used to uniquely identify and represent objects in thermal images. TFM is represented in more compact way as a triple matrix. It is a simple and accurate descriptor suitable for tracking objects in thermal video sequences without an identity switch. The proposed Pedestrian tracking system uses most of the advantages of thermal cameras by overcoming challenges in thermal videos effectively based on a novel descriptor TFM. The proposed system is evaluated with various data sets, and the results are analysed using true positive, true negative, false negative, false positive, accuracy, precision, recall, F-score, global identity mismatch (GMME) and track matching error (TME). The performance metrics such as accuracy, precision, recall, F-score, GMME and TME are computed as 99%, 100%, 99%, 99%, 2.3%, and 2.1%, respectively. From the observation, it is found that the performance of proposed TFM-based system is significantly improved. The experimental result shows that the proposed system achieved more accurate tracking compared to the conventional methods. [ABSTRACT FROM AUTHOR]

This paper reports the influence of thickness and material attenuation on volumetric inspection using conventional and advanced ultrasonic array-based techniques through suitable examples. The sensitivity achieved in conventional phased array ultrasonic testing technique with focusing at specific depth using delay laws and advanced array-based techniques for simultaneous focusing at all depths such as Full Matrix Capture-Total Focusing Method and plane wave imaging-TFM are compared in the present study. Finally, experimental results are discussed for advanced ultrasonic array-based techniques for detection and characterization of a 4 mm through wall dimension vertical planar defect (simulating a lack of side wall fusion in a thick narrow gap weld) in a nickel base alloy forging having fine and coarse grains. The sensitivities and signal-to-noise ratio achieved in the different techniques are discussed in detail. [ABSTRACT FROM AUTHOR]

Reliable inspection of large steel forgings is a significant problem across multiple industries. When the dimensions of forgings are at least 1000 mm in each direction, ultrasonic phased array inspection becomes difficult because conventional probes are not designed to transmit and focus acoustic energy over such large distances. Using simulations and experiments, this article aims to discuss the possibilities and limitations of phased array imaging of large forged steel ingots. Simulations were used to design a transducer based on the reflected amplitude, as well as the lateral and axial resolutions of defects in a 1000 mm thick block. It was shown that when limiting the aperture to allow easy handling in an industrial inspection setting, the lateral resolution and the reflected amplitude were the main limitations. Increasing the element width maximizes the energy transmitted into the material, but it also moves elements away from each other, thus reducing the lateral resolution. Based on the simulations, an experimental phased array transducer was manufactured with eight elements of 9.25 × 22.5 mm. The probe was used to perform measurements and generate total focusing method images of three different at a depth of 370 mm in a 776 mm forged steel block. [ABSTRACT FROM AUTHOR]

Given the growing importance of customer behavior in the business market nowadays, telecom operators focus not only on customer profitability to increase market share but also on highly loyal customers as well as customers who are churn. The emergence of big data concepts introduced a new wave of Customer Relationship Management (CRM) strategies. Big data analysis helps to describe customer's behavior, understand their habits, develop appropriate marketing plans for organizations to identify sales transactions and build a long-term loyalty relationship. This paper provides a methodology for telecom companies to target different-value customers by appropriate offers and services. This methodology was implemented and tested using a dataset that contains about 127 million records for training and testing supplied by Syriatel corporation. Firstly, customers were segmented based on the new approach (Time-frequency- monetary) TFM (TFM where: Time (T): total of calls duration and Internet sessions in a certain period of time. Frequency (F): use services frequently within a certain period. Monetary (M): The money spent during a certain period.) and the level of loyalty was defined for each segment or group. Secondly, The loyalty level descriptors were taken as categories, choosing the best behavioral features for customers, their demographic information such as age, gender, and the services they share. Thirdly, Several classification algorithms were applied based on the descriptors and the chosen features to build different predictive models that were used to classify new users by loyalty. Finally, those models were evaluated based on several criteria and derive the rules of loyalty prediction. After that by analyzing these rules, the loyalty reasons at each level were discovered to target them the most appropriate offers and services. [ABSTRACT FROM AUTHOR]

Copyright of Knowledge & Management of Aquatic Ecosystems is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Gas-solid fluidization is intrinsically dynamic and manifests mesoscale structures spanning a wide range of length and timescales. When involved with reactions, more complex phenomena emerge and thus pose bigger challenges for modeling. As the mesoscale is critical to understand multiphase reactive flows, which the conventional two-fluid model without mesoscale modeling may be inadequate to resolve even using extremely fine grids, this review attempts to demonstrate that the energy-minimization multiscale (EMMS) model could be a starting point to develop such mesoscale modeling. Then, the EMMS-based mesoscale modeling with emphasis on formulation of drag coefficients for different fluidization regimes, modification of mass transfer coefficient, and other extensions are discussed in an attempt to resolve the emerging challenges. Its applications with examples of development of novel fluid catalytic cracking and methanol-to-olefins processes prove that the mesoscale modeling plays a remarkable role in improving the predictions in hydrodynamic behaviors and overall reaction rate. However, the product content primarily depends on the chemical kinetic model itself, suggesting the necessity of an effective coupling between chemical kinetics and flow characteristics. The mesoscale modeling can be believed to accelerate the traditional experimental-based scale-up process with much lower cost in the future. [ABSTRACT FROM AUTHOR]

Copyright of Education & Law Review / Revista de Educación y Derecho is the property of Revista de Educacion y Derecho and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Real-time imaging, using ultrasound techniques, is a complex task in non-destructive evaluation. In this context, fast and precise control systems require design of specialized parallel architectures. Total focusing method (TFM) for ultrasound imaging has many advantages in terms of flexibility and accuracy in comparison to traditional imaging techniques. However, one major drawback is the high number of data acquisitions and computing requirements for this imaging technique. Due to those constraints, the TFM algorithm was earlier classified in the field of post-processing tasks. This paper describes a multi-FPGA architecture for real-time TFM imaging using the full matrix capture (FMC). In the acquisition process, data are acquired using a phased array and processed with synthetic focusing techniques such as the TFM algorithm. The FMC-TFM architecture consists of a set of interconnected FPGAs integrated on an embedded system. Initially, this imaging system was dedicated to data acquisition using a phased array. The algorithm was reviewed and partitioned to parallelize processing tasks on FPGAs. The architecture was entirely described using VHDL language, synthesized and implemented on a V5FX70T Xilinx FPGA for the control and high-level processing tasks and four V5SX95T Xilinx FPGAs for the acquisition and low-level processing tasks. The designed architecture performs real-time FMC-TFM imaging with a good characterization of defects. [ABSTRACT FROM AUTHOR]

Cell contraction regulates how cells sense their mechanical environment. We sought to identify the set-point of cell contraction, also referred to as tensional homeostasis. In this work, bovine aortic endothelial cells (BAECs), cultured on substrates with different stiffness, were characterized using traction force microscopy (TFM). Numerical models were developed to provide insights into the mechanics of cell-substrate interactions. Cell contraction was modeled as eigenstrain which could induce isometric cell contraction without external forces. The predicted traction stresses matched well with TFM measurements. Furthermore, our numerical model provided cell stress and displacement maps for inspecting the fundamental regulating mechanism of cell mechanosensing. We showed that cell spread area, traction force on a substrate, as well as the average stress of a cell were increased in response to a stiffer substrate. However, the cell average strain, which is cell type-specific, was kept at the same level regardless of the substrate stiffness. This indicated that the cell average strain is the tensional homeostasis that each type of cell tries to maintain. Furthermore, cell contraction in terms of eigenstrain was found to be the same for both BAECs and fibroblast cells in different mechanical environments. This implied a potential mechanical set-point across different cell types. Our results suggest that additional measurements of contractility might be useful for monitoring cell mechanosensing as well as dynamic remodeling of the extracellular matrix (ECM). This work could help to advance the understanding of the cell-ECM relationship, leading to better regenerative strategies. [ABSTRACT FROM AUTHOR]

The sea lamprey (Petromyzon marinus) is a destructive invasive species in the Great Lakes. Since the 1960s, tons of the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) has been applied to selected tributaries each year to eliminate or reduce sea lamprey larval populations. Therefore, the environmental impact of TFM needs to be evaluated. However, the metabolism of TFM and its mechanism of selective toxicity in sea lamprey is not yet fully understood. Based upon our previous report on the identification, synthesis, and characterization of TFM metabolites observed in liver incubates from sea lamprey and non-target fishes, we now provide a robust assay for quantifying TFM and its metabolites in fish liver tissue. This method is important for assessing bioaccumulation of TFM in the ecosystems. The compounds purified in our previous report were used to develop and validate a quantitative ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) assay for TFM and TFM metabolites formed in vivo. Several sample preparation techniques were compared, and a protein precipitation method was selected. The unavailability of stable isotopic internal standards was overcome by using a matrix matching method. After a thorough validation, this method was applied to determine the concentrations of TFM and its metabolites in fish liver tissues from animals exposed to TFM, and in the comparison between dead animals and survivors. Seven of eight expected metabolites were observed, some for the first time in vivo. Our results indicate that in vivo nitroreduction, glucuronidation, sulfation, and glutathione conjugation are involved in TFM metabolism in sea lamprey. [ABSTRACT FROM AUTHOR]

The sea lamprey (Petromyzon marinus) is a destructive invasive species in the Great Lakes that contributed to the collapse of native fish populations in the mid-1900s. 3-Trifluoromethyl-4-nitrophenol (TFM) is a selective pesticide that has been applied to sea lamprey infested tributaries of the Great Lakes to kill larvae since the 1960s and has reduced the populations by as much as 90%. However, the metabolism of TFM by sea lamprey and non-target species is not fully illuminated. Elucidation of TFM metabolism is critical for understanding its mode of action and possible environmental impact. Here, we describe the screening, identification, synthesis and structural characterization of TFM metabolites in livers from sea lamprey and three non-target species that differ in their ability to survive TFM exposure. We identified glucuronidation, sulfation, N-acetylation, glutathione conjugation, and aromatic nitro group reduction as potential detoxification mechanisms. Seven metabolites were synthesized for use as markers of TFM metabolism in fish. Quantitative 1H NMR was used to assay synthesized metabolite stock solutions that were then used as standard material to develop a quantitative LC-MS/MS method for TFM metabolites. [ABSTRACT FROM AUTHOR]

Cells dynamically assemble and organize into complex tissues during development, and the resulting three-dimensional (3D) arrangement of cells and their surrounding extracellular matrix in turn feeds back to regulate cell and tissue function. Recent advances in engineered cultures of cells to model 3D tissues or organoids have begun to capture this dynamic reciprocity between form and function. Here, we describe the underlying principles that have advanced the field, focusing in particular on recent progress in using mechanical constraints to recapitulate the structure and function of musculoskeletal tissues. [ABSTRACT FROM AUTHOR]

The present study evaluated the risk of 12-h exposures of the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) to multiple life stages of the federally endangered snuffbox ( Epioblasma triquetra) and its primary host fish the common logperch ( Percina caprodes) as well as a surrogate to the snuffbox, the ellipse ( Venustaconcha ellipsiformis). Life stages examined included free glochidia, 1-wk juveniles, and adults of the ellipse; free glochidia, glochidia on host fish, and 1-wk juveniles of the snuffbox; and adult logperch. Larval sea lampreys were also tested alongside adult ellipse and logperch for direct comparison. Survival exceeded 82% among all life stages in both mussel species at levels up to 1.8 times what would be applied during treatments, suggesting that routine sea lamprey control operations would not adversely affect mussels. However, substantial mortality of adult logperch was observed at TFM concentrations typically applied to streams, and loss of host fish could adversely affect snuffbox reproduction. In addition, TFM had no significant effect on the number of glochidia that metamorphosed on adult logperch. Although the snuffbox is not likely to be acutely affected from sea lamprey control operations, mitigation efforts to minimize impacts to the host fish should be considered. Environ Toxicol Chem 2015;34:1634-1641. © 2015 SETAC [ABSTRACT FROM AUTHOR]

The ability of the two fluid method (TFM) to predict the gas-solid flow phenomenon in conical spouted beds operated with high density (6050 kg m−3) particles simulating the nuclear fuel coating conditions is investigated. The effects of geometric and operational factors, such as conical angle and static bed height, are also assessed. The results show that TFM predicts the time-averaged bed pressure drop quite well. The qualitative variation of the particle velocity, solids volume fraction, and axial particle flux with axial height are captured by the simulations. The simulated trends observed in the investigation of the effects of static bed height and conical angle on the particle velocity, solids volume fraction, and axial particle flux agree well with those of the experimental measurements. [ABSTRACT FROM AUTHOR]

To reduce the time of recording echo signals by an antenna array that operates in the double-scanning mode, it was proposed to use a set of pseudo-orthogonal coding signals. As the coding signals, it is possible to use frequency-modulated signals or phase-manipulated signals according to the Kasami code by analogy to the FDMA or CDMA techniques for multichannel communication. The use of the maximum-entropy method for decoding echo signals made it possible to reduce the noise level and increase the longitudinal resolution of reflector images in comparison to the case of using matched filtering. If an image is formed as the coherent sum of several partial images that are reconstructed using the C-SAFT method for various positions of the antenna array, it is proposed to use several sets of Kasami codes in order to additionally reduce the noise level by more than 6 dB. Numerical experiments show the efficiency of the proposed approach. [ABSTRACT FROM AUTHOR]

It is proposed to use the inverse C-SAFT (invC-SAFT) method to provide spatial-sensitivity equalization (SSE), which takes not only the delay times of the arrival of echo signals but also their amplitudes and phase nonuniformities into account. The invC-SAFT method reconstructs images of reflectors with a uniform scattering indicatrix in the form of reflections whose amplitudes change within ±2 dB; thus, the invC-SAFT method possesses the property of 'inborn' spatial-sensitivity leveling. Numerical and model experiments at longitudinal and transverse waves confirm the efficiency of the proposed SSE method for nondirectional reflectors. [ABSTRACT FROM AUTHOR]

The possibility for the application of an elastic organosilicon polymer (aquapolymer) as an immersion medium for providing a stable acoustic contact between a tested object with a rough surface and an antenna array in automated ultrasonic testing is considered. If the form of the surface is known, it can be accounted for in the C-SAFT method for the reconstruction of a reflector image using echo signals. A surface profile can be obtained by either direct measurement using a profilometer or by analysis of the reconstructed surface image. An algorithm for processing a surface that was reconstructed using the C-SAFT method is proposed for automatic acquisition of information on the profile of the surface. The operability of the proposed method of reflector-image acquisition with consideration of the rough surface of a tested object is demonstrated in model experiments. [ABSTRACT FROM AUTHOR]

A method that is proposed for calibrating an antenna array that is installed on a wedge provides refinement of the coordinates of the centers of piezoelectric elements. Precise knowledge of the coordinates will make it possible to obtain images in which reflections from reflectors will coincide with their actual positions with an accuracy no worse than a half wavelength. The calibration principle involves the minimization of the objective function that describes the difference between the antenna-array-measured echo signals from a 2-mm-diameter side drilled hole (SDH) at a depth of 12 mm and the calculated echo signals from the same hole. The algorithm operation was tested for echo signals calculated in the CIVA program. The calibration results for several antenna arrays on wedges and images of an SDH are presented, which were obtained using the method for digital antenna-array focusing (DAAF) for various acoustic systems. [ABSTRACT FROM AUTHOR]

The application of the digital image focusing (DFA) method to the determination of the types of detected reflectors is considered. For this purpose two antenna arrays (AAs) are used, which are placed on opposite sides of the reflector and using which echo signals are recorded in three acoustic channels in the double-scanning mode. The first and second acoustic channels transmit and receive echo signals using the first and second AA, respectively, and the third channel is tuned so that the first AA transmits pulses and the second AA receives echo signals. Using signals in each channel, many partial images can be reconstructed in a common coordinate system according to different acoustic schemes with allowance for both multiple reflections from irregular boundaries of a tested object and effects of transformation of the wave types. Combining partial images makes it possible to obtain a high-quality image, in which the entire boundary of the reflector is seen and using which an attempt to automate the procedure of evaluating the reflector size and determining its type was made. Such an approach allows one to reduce the subjective influence of an operator on the testing results. It is shown that in order to increase the image resolution, the spectrum of echo signals can be extrapolated by the spectrum splitting method jointly with the construction of an AR model of their spectrum. The results of model experiments that confirm the possibility of determining the reflector type are presented. [ABSTRACT FROM AUTHOR]

This paper considers the features of forming the images of reflectors using phased antenna array technology and the images obtained by the C-SAFT method by echo signals measured in by double-scanning mode. It is shown that in some cases the images obtained by the phased antenna array technology are less informative, while the images obtained by the C-SAFT method have a higher frontal resolution over the entire area of image restoration; the partial images restored at different positions of the antenna array can be coherently combined to obtain a high and homogeneous resolution throughout the entire volume of thickwalled articles and increasing the signal/noise ratio. For the sake of brevity, the registration of echo signals in the double-scanning mode and restoration of the images of reflectors by the C-SAFT method will be called digital focusing by an antenna array (DFA). The ability to restore the partial images of reflectors by once measured echo signals according to many acoustic schemes with their consequent combination into one high-quality image should provide reliable automation of the process of recognition and dimensioning of scatterers. Another advantage of the images obtained by the C-SAFT method with three-dimensional focusing is the possibility of restoring images in the same coordinate system when using antenna arrays on prisms of different configurations. This facilitates the joint analysis of the images. Speeds of forming the images by the technology of phased-antenna arrays and the images obtained by the C-SAFT method are comparable. If the testing technique is based on the use of nonlinear effects, then in this case PA flaw detectors have a distinct advantage over DFA flaw detectors. However, within the framework of linear acoustics, PA flaw detectors have no fundamental advantages over DFA flaw detectors. It is fairer to say that PA flaw detectors have drawbacks. This article shows images that illustrate the features of the images that were obtained by PA and DFA flaw detectors. [ABSTRACT FROM AUTHOR]

A modified method of combined SAFT (C-SAFT) for restoring the images of reflectors is considered; it allows the multiple reflection of a pulse from the boundaries of the wall of a cylindrical inspection object. To verify the efficiency of the proposed algorithm, images of a crack were restored from echo signals that were calculated using the CIVA software package, which is intended for modeling the propagation and scattering of ultrasonic pulses. It was shown in a model experiment that the consideration of changes in the pulse phase during reflection from the inspection-object boundaries at various incident angles of an S-wave in the image-restoration algorithm increases the frontal resolution by more than two times. The consideration of five reflections from the inspection-object boundaries made it possible to obtain images of reflectors by the M-C-SAFT method using many acoustic schemes. The images allow one to determine the type of defects, as well as their dimensions and location in the depth of the wall of a pipeline that is 720 mm in diameter. [ABSTRACT FROM AUTHOR]

Fluidized bed spray granulation is used to produce porous granular particles from suspensions, solutions, and melts. In this work, the drying of the spray and the drying of the particles in the fluidized bed are simulated using the Two Fluid Model (TFM) with the Eulerian-Eulerian approach. Using the wetted surfaces of the particle, the dust integration is implemented. The model is used to simulate the particle growth for a semi-batch fluidized bed spray granulation process. [ABSTRACT FROM AUTHOR]

The application of antenna matrices (AMs) for obtaining flaw images during automated nondestructive ultrasonic testing is considered. The conventional technique of using an AM as a phased AM (PAM) has a number of drawbacks. One of them is related to the small number of AM elements and consists in a low frontal resolution of the thus-formed images. Scanning with an AM operating in the double scanning mode, viz., the so-called triple-scanning mode, allows coherent summation of partial images for each position and obtaining a resulting image with a frontal resolution that cannot be attained with a PAM. In order to test the serviceability of the proposed algorithm in the CIVA program, echo signals reflected from a crack model with a height of 6 mm and a length of 30 mm in a tested object, which simulated a welded joint of a pipeline with a conventional diameter of 800 mm (дy800), were calculated. The results of the reconstruction of images of model objects in the form of a drilled side hole with a diameter of 6 mm at a depth of 15 mm in a CO-2 specimen and a fatigue crack in a welded joint of a д y800 pipeline are presented. To reduce the influence of reverberation noise, a B-type median template was subtracted from echo signals. The flaw images that were reconstructed in numerical and model experiments demonstrate the efficiency of the proposed algorithm. [ABSTRACT FROM AUTHOR]

The application of antenna arrays (AAs) for obtaining flaw images during automated non-destructive testing is considered. The conventional technique of using an AA as a phased AA has a number of drawbacks. An alternative approach is proposed in which echo signals are registered using an AA operating in the double scanning mode, and a modified algorithm of the combined SAFT, which takes into account multiray ultrasound propagation with consideration of transformations of wave types upon reflections from irregular boundaries of a test object, is used to obtain flaw images. The results of testing a specimen with a model of a volumetric flaw in the form of a 2-mm-diameter side hole drilled at a depth of 12 mm and a specimen with a crack model with a tip at a 12-mm depth are presented. Both specimens have rough bottoms. The obtained images allow determination of not only the dimensions and locations of flaws, but also their type. [ABSTRACT FROM AUTHOR]

In adulthood, the action of androgens on seminiferous tubules is essential for full quantitatively normal spermatogenesis and fertility. In contrast, their role in the fetal testis, and particularly in fetal germ cell development, remains largely unknown. Using testicular feminized (Tfm) mice, we investigated the effects of a lack of functional androgen receptor (AR) on fetal germ cells, also named gonocytes. We demonstrated that endogenous androgens/AR physiologically control normal gonocyte proliferation. We observed an increase in the number of gonocytes at 17.5 days postconception resulting from an increase in proliferative activity in Tfm mice. In a reciprocal manner, gonocyte proliferation is decreased by the addition of DHT in fetal testis organotypic culture. Furthermore, the AR coregulator Hsp90αa (mRNA and protein) specifically expressed in gonocytes was down-regulated in Tfm mice at 15.5 days postconception. To investigate whether these effects could result from direct action of androgens on gonocytes, we collected pure gonocyte preparations and detected AR transcripts therein. We used an original model harboring a reporter gene that specifically reflects AR activity by androgens and clearly demonstrated the presence of a functional AR protein in fetal germ cells. These data provide in vivo and in vitro evidence of a new control of endogenous androgens on gonocytes identified as direct target cells for androgens. Finally, our results focus on a new pathway in the fetal testis during the embryonic period, which is the most sensitive to antiandrogenic endocrine disruptors. [ABSTRACT FROM AUTHOR]

In the following study, we asked which steroid receptors regulate aggression and arginine vasopressin (AVP) immunoreactivity (– ir) in several limbic regions. Using spontaneous mutant and knockout mice, we generated a novel cross of mice whose offspring lacked estrogen receptor α (ERα), androgen receptor (AR) or both ERα and AR. The wild-type (WT) males and females were compared with ERα knockout (ERαKO) male, mutated AR (Tfm) male and ERαKO/Tfm (double knockout; DKO) male littermates. Animals were gonadectomized and treated with 17β-estradiol (E2) prior to resident-intruder aggression tests. WT and Tfm males showed aggression whereas WT females, ERαKO and DKO males did not. In the lateral septum, WT and Tfm male brains had significantly denser AVP-ir as compared with WT females and DKO males. ERαKO male brains were intermediate in the amount of AVP-ir present. In the medial amygdala, brains from all genotypes had equivalent AVP-ir, except DKO males, which had significantly less AVP-ir. Overall, the expression of aggressive behavior coincided with AVP-ir in WT, Tfm and DKO males. However, in ERαKO males and WT females, the amount of AVP-ir was not associated with resident-intruder aggression. In sum we have shown that E2 acts via ERα to regulate aggression in male mice. In contrast both ERα and AR contribute to AVP-ir in limbic brain regions. [ABSTRACT FROM AUTHOR]

The reliability of the ultrasonic phased array total focusing method (TFM) imaging of parts with curved geometries depends on many factors, one being the probe standoff. Strong artifacts and resolution loss are introduced by some surface profile and standoff combinations, making it impossible to identify defects. This paper, therefore, introduces a probe standoff optimization method (PSOM) to mitigate such effects. Based on a point spread function analysis, the PSOM algorithm finds the standoff with the lowest main lobe width and side lobe level values. Validation experiments were conducted and the TFM imaging performance compared with the PSOM predictions. The experiments consisted of the inspection of concave and convex parts with amplitudes of 0, 5 and 15 λAl, at 12 standoffs varying from 20 to 130 mm. Three internal side-drilled holes at different depths were used as targets. To investigate how the optimal probe standoff improves the TFM, two metrics were used: the signal-to-artifact ratio (SAR) and the array performance indicator (API). The PSF characteristics predicted by the PSOM agreed with the quality of TFM images. A considerable TFM improvement was demonstrated at the optimal standoff calculated by the PSOM. The API of a convex specimen's TFM was minimized, and the SAR gained up to 13 dB, while the image of a concave specimen gained up to 33 dB in SAR. [ABSTRACT FROM AUTHOR]

We use the Tfm (testicular feminization) mutation of the mouse to reexamine the role of Wolffian and Müllerian ducts during formation of the vagina. Threedimensional graphical reconstructions of the lower genital tract are prepared from serial sections of male, female, and Tfm embryos from day 15 p.c. until 8 days after birth. The reconstructions show that in female and Tfm animats the caudal segments of Wolffian and Müllerian ducts fuse and migrate caudally, whereas in the male they do not fuse and remain in their original position. Following down-growth, separate Wolffian and Müllerian ducts emerge from the fused caudal tips of the ducts. The Wolffian ducts degenerate, while the Müllerian ducts fuse with each other and form the vagina. Wolffian and Müllerian ducts are connected to the urogenital sinus by the sinus ridges which in later stages are separated from the sinus by lateral furrows. The sinus ridges are replaced by the Müllerian ducts. We conclude that the vagina develops by down-growth of Wolffian and Müllerian ducts along the sinus ridges. Wolffian ducts and sinus ridges regress so that the definitive vagina is formed by the Müllerian ducts. In Tfm embryos the vagina forms as in the female but subsequently degenerates, probably due to the action of AMH. The vaginal pocket in the Tfm is the variable remainder of the vagina at the end of the degeneration process. [ABSTRACT FROM AUTHOR]

Time of flight diffraction (TOFD) is considered a reliable non-destructive testing method for the inspection of welds using a pair of single-element probes. On the other hand, ultrasonic phased array imaging has been continuously developed over the last couple of decades, and now features powerful algorithms, such as the total focusing method (TFM) and its multi-view approach to rendering detailed images of inspected parts. This article focuses on a different implementation of the TFM algorithm, relying on the coherent summation of the instantaneous signal phase. This approach presents a wide range of benefits, such as removing the need for calibration, and is highly sensitive to defect tips. This study compares the sizing and localization capabilities of the proposed method with the well-known TOFD. Both instantaneous phase algorithm and TOFD do not take advantage of the signal amplitude. Experimental tests were performed on a ¾″-thick steel sample with crack-like defects at different angles. Phase-based imaging techniques showed similar characterization capabilities as the standard TOFD method. However, the proposed method adds the benefit of generating an easy-to-interpret image that can help in localizing the defect. These results pave the way for a new characterization approach, especially in the field of automated ultrasonic testing (AUT). [ABSTRACT FROM AUTHOR]

Summary Cytoskeletal actin dynamics is essential for T cell activation. Here, we show evidence that the binding kinetics of the antigen engaging the T cell receptor influences the nanoscale actin organization and mechanics of the immune synapse. Using an engineered T cell system expressing a specific T cell receptor and stimulated by a range of antigens, we found that the peak force experienced by the T cell receptor during activation was independent of the unbinding kinetics of the stimulating antigen. Conversely, quantification of the actin retrograde flow velocity at the synapse revealed a striking dependence on the antigen unbinding kinetics. These findings suggest that the dynamics of the actin cytoskeleton actively adjusted to normalize the force experienced by the T cell receptor in an antigen-specific manner. Consequently, tuning actin dynamics in response to antigen kinetics may thus be a mechanism that allows T cells to adjust the lengthscale and timescale of T cell receptor signaling. Graphical Abstract Highlights • Mechanical force experienced by the TCR at the immune synapse is actin dependent • Peak forces experienced by the TCR are independent of the antigen unbinding kinetics • Actin velocity at the immune synapse is dependent on the stimulating antigen T cell activation relies on a dynamic actin cytoskeleton. Here, Colin-York et al. show how the kinetics of the stimulating antigen influence the dynamics of actin. This feedback mechanism influences the mechanics at the immune synapse, allowing T cells to orchestrate the length scale and timescale of signaling. [ABSTRACT FROM AUTHOR]

The pesticide 3-trifluoromethyl-4-nitrophenol (TFM) is used to control sea lamprey populations in the Great Lakes and Lake Champlain. Little is known about the effects of this pesticide on gene expression in eukaryotic species. This study used microarray analysis to determine the effects of short term, high dose TFM exposure on gene expression in Saccharomyces cerevisiae. Yeast grown in standard glucose-containing media showed significant variation in gene expression in pathways related to cytoplasmic translation with the majority of these genes being downregulated. These findings were supported by the analysis of a similar but glucose-free experiment revealing that these cytoplasmic translation genes, mostly ribosomal subunit expressing genes, were similarly downregulated. The repression of the ribosomal subunit genes suggests that TFM exposure, regardless of glucose availability, evokes features of the environmental stress response in yeast. [ABSTRACT FROM AUTHOR]

Lined pipe girth weld regions are challenging to inspect using ultrasonic techniques due to their anisotropic and inhomogeneous characteristics, which lead to noise and acoustic beam distortion. This paper is focused on the application of coherence weighting methods to decrease the background noise level and false indications on total focusing method (TFM) images, encompassing the triple boundary of mechanically lined pipes. Three coherence weighting approaches were used here; the coherence factor (CF), the sign CF (SCF) and the phase CF (PCF). All three were found capable to improve the TFM images, however, the CF and the SCF performed better due to their exponential sensitivity factors, unlike the PCF which has a linear sensitivity factor. [ABSTRACT FROM AUTHOR]