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Colorectal cancer (CRC) has been addressed in the framework of molecular, cellular biology, and biochemical traits. A new approach to studying CRC is focused on the relationship between biochemical pathways and biophysical cues, which may contribute to disease understanding and therapy development. Herein, we investigated the mechanical properties of CRC cells, namely, HCT116, HCT15, and SW620, using static and dynamic methodologies by atomic force microscopy (AFM). The static method quantifies Young’s modulus; the dynamic method allows the determination of elasticity, viscosity, and fluidity. AFM results were correlated with confocal laser scanning microscopy and cell migration assay data. The SW620 metastatic cells presented the highest Young’s and storage moduli, with a defined cortical actin ring with distributed F-actin filaments, scarce vinculin expression, abundant total focal adhesions (FAK), and no filopodia formation, which could explain the lessened migratory behavior. In contrast, HCT15 cells presented lower Young’s and storage moduli, high cortical tubulin, less cortical F-actin and less FAK, and more filopodia formation, probably explaining the higher migratory behavior. HCT116 cells presented Young’s and storage moduli values in between the other cell lines, high cortical F-actin expression, intermediate levels of total FAK, and abundant filopodia formation, possibly explaining the highest migratory behavior.

Background Metaconcrete is a new concept of concrete, showing marked attenuation properties under impact and blast loading, where traditional aggregates are partially replaced by resonant bi-material inclusions. In a departure from conventional mechanical metamaterials, the inclusions are dispersed randomly as cast in the material. The behavior of metaconcrete at supersonic frequencies has been investigated theoretically and numerically and confirmed experimentally. Objective The feasibility of metaconcrete to achieve wave attenuation at low frequencies demands further experimental validation. The present study is directed at characterizing dynamically, in the range of the low sonic frequencies, the—possibly synergistic—effect of combinations of different types of inclusions on the attenuation properties of metaconcrete. Methods Dynamic tests are conducted on cylindrical metaconcrete specimens cast with two types of spherical inclusions, made of a steel core and a polymeric coating. The two inclusions differ in terms of size and coating material: type 1 inclusions are 22 mm diameter with 1.35 mm PDMS coating; type 2 inclusions are 24 mm diameter with 2 mm layer natural rubber coating. Linear frequency sweeps in the low sonic range (< 10 kHz), tuned to numerically estimated inclusion eigenfrequencies, are applied to the specimens through a mechanical actuator. The transmitted waves are recorded by transducers and Fast-Fourier transformed (FFT) to bring the attenuation spectrum of the material into full display. Results Amplitude reductions of transmitted signals are markedly visible for any metaconcrete specimens in the range of the inclusion resonant frequencies, namely, 3,400-3,500 Hz for the PDMS coating inclusions and near 3,200 Hz for the natural rubber coating inclusions. Specimens with mixed inclusions provide a rather uniform attenuation in a limited range of frequencies, independently of the inclusion density, while specimens with a single inclusion type are effective over larger frequency ranges. With respect to conventional concrete, metaconcrete reduces up to 90% the amplitude of the transmitted signal within the attenuation bands. Conclusions Relative to conventional concrete, metaconcrete strongly attenuates waves over frequency bands determined by the resonant frequencies of the inclusions. The present dynamical tests conducted in the sonic range of frequencies quantify the attenuation properties of the metaconcrete cast with two types inclusions, providing location, range and intensity of the attenuation bands, which are dependent on the physical-geometric features of the inclusions.

The objective of the study was to investigate and demonstrate the application of frequency-sweep dynamic acoustic fields for size-selective particle filtration on centimeter scale in a regulated continuous flow. The 3D-printed prototype of the acoustic separator has two inlets and two outlets, whereas the dynamic acoustic field is generated between a transducer, operating in the MHz range, and a reflector. The measured frequency response of the prototype was input to computer models, and simulations were carried out to explore the effects of the sweep period and the flow parameters on the filtration performance. A design-of-experiments study showed that the filtration performance is largely affected by the sweep period and the outlet flow rate. Lab experiments with model particle mixtures demonstrated the size selective filtration performance of the prototype with a total flow rate of 1 L h - 1 . A mixture with unknown properties was also used to demonstrate the selective filtration performance of the prototype.

The ability to rapidly encode the direction of frequency contour contained in frequency-modulated (FM) sweeps is essential for speech processing, music appreciation, and conspecific communications. Psychophysical evidence points to a common temporal window threshold for human listeners in processing rapid changes in frequency glides. No neural evidence has been provided for the existence of a cortical temporal window threshold underlying the encoding of rapid transitions in frequency glides. The present magnetoencephalography study used the cortical mismatch negativity activity (MMNm) to investigate the minimum temporal window required for detecting different magnitudes of directional changes in frequency-modulated sweeps. A deviant oddball paradigm was used in which directional upward or downward frequency sweep serves as the standard and the same type of sweep with the opposite direction serves as its deviant. Stimuli consisted of unidirectional linear frequency-sweep complexes that swept across speech-relevant frequency bands in durations of 10, 20, 40, 80, 160, and 320 ms (with corresponding rates of 50, 25, 12.5, 6.2, 3.1, 1.5 oct/s). The data revealed significant magnetic mismatch field responses across all sweep durations, with slower-rate sweeps eliciting larger MMNm responses. A greater temporally related enhancement in MMNm response was obtained for rising but not falling frequency sweep contours. A hemispheric asymmetry in the MMNm response pattern was observed corresponding to the directionality of frequency sweeps. Contrary to psychophysical findings, we report a temporal window as short as 10 ms sufficient to elicit a robust MMNm response to a directional change in speech-relevant frequency contours. The results suggest that auditory cortex requires extremely brief temporal window to implicitly differentiate a dynamic change in frequency of linguistically relevant pitch contours. That the brain is extremely sensitive to fine spectral changes contained in speech-relevant glides provides cortical evidence for the ecological importance of FM sweeps in speech processing.

As a result of increasing variability of network impedance, interest in impedance estimation techniques is growing. This review contextualises local impedance estimation techniques by providing a historical prospective on the uses of these techniques, from the early implementations designed to monitor power quality to the latest techniques integrated into converters designed to update the controller with the most recent network information. This is followed by clear and consolidated descriptions, a complete classification and comparison tables of local estimation techniques intended to assist engineers and researchers choose an estimation technique that is suitable to their application. The discussed techniques are then ranked for a range of application priorities such as accuracy, least disruptive to the network, most suitable for wide frequency spectrum estimations and rapidity of estimation. Practical applications of impedance estimation are discussed, such as network characterisation, anti-islanding detection, filter resonance avoidance and controller tuning. To conclude the review, future trends are identified.

The aim of this study was to investigate the rheological properties and storage stability of submicron O/W emulsions formulated with dried skim milk and vegetable oil at neutral pH, and to analyse the impact of their inclusion into starch suspension. Sunflower oil droplets were pre-emulsified in skim milk suspension by a rotor-stator homogenizer and further an ultrasonic treatment was applied. Droplets sizes decreased after applying ultrasound (US) from 1.4 to 0.4 μm (d32). Emulsions exhibited Bingham flow behaviour and the plastic viscosity increased upon 14 days of storage at 5 °C. Flocculation may be responsible for the increase in viscosity with aging time. Mixed colloidal dispersions (submicron emulsions embedded into starch matrix) showed shear-thinning behaviour. Over storage, light microscope micrographs suggested deposited droplets on the starch granules surface. Flow and viscoelastic behaviour of mixed colloidal dispersions indicated droplets flocculation, attributable to a reversible depletion mechanism of destabilization. Fil: Alfano, E.H.. Universidad Nacional de Luján. Departamento de Tecnología; Argentina Fil: Crosta, T.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina Fil: Martinez, María Julia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina Fil: Perez, Oscar Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; Argentina Fil: Farías, María Edith. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de Luján. Departamento de Tecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina

Coherent ranging, also known as frequency-modulated continuous-wave (FMCW) laser based ranging (LIDAR) is currently developed for long range 3D distance and velocimetry in autonomous driving. Its principle is based on mapping distance to frequency, and to simultaneously measure the Doppler shift of reflected light using frequency chirped signals, similar to Sonar or Radar. Yet, despite these advantages, coherent ranging exhibits lower acquisition speed and requires precisely chirped and highly-coherent laser sources, hindering their widespread use and impeding Parallelization, compared to modern time-of-flight (TOF) ranging that use arrays of individual lasers. Here we demonstrate a novel massively parallel coherent LIDAR scheme using a photonic chip-based microcomb. By fast chirping the pump laser in the soliton existence range of a microcomb with amplitudes up to several GHz and sweep rate up to 10 MHz, the soliton pulse stream acquires a rapid change in the underlying carrier waveform, while retaining its pulse-to-pulse repetition rate. As a result, the chirp from a single narrow-linewidth pump laser is simultaneously transferred to all spectral comb teeth of the soliton at once, and allows for true parallelism in FMCW LIDAR. We demonstrate this approach by generating 30 distinct channels, demonstrating both parallel distance and velocity measurements at an equivalent rate of 3 Mpixel/s, with potential to improve sampling rates beyond 150 Mpixel/s and increase the image refresh rate of FMCW LIDAR up to two orders of magnitude without deterioration of eye safety. The present approach, when combined with photonic phase arrays based on nanophotonic gratings, provides a technological basis for compact, massively parallel and ultra-high frame rate coherent LIDAR systems., Comment: 18 pages, 12 Figures

Heating energy represents a significant proportion of the total energy consumption of theFederal Republic of Germany. Thus, a reduction of heating energy demand in buildings is one of the central points of German energy saving and climate goals. Considering that the current rate of new building construction is approximately 1 %, the most significant energy saving potential lies in existing buildings. The analysis of existing buildings will thus become more important in the years to come. As a result, the development of new measurement systems to assess the need for renovation is required. In this context, detailed Information about heat insulation and airtightness is essential. The current approaches to detect air leakage in building envelopes are mostly time consuming and expensive. Therefore, the development of an advanced and more inexpensive method is a vital step. In this paper, we2 present a study about the feasibility and suitability of ultrasound technology to evaluate the size of air leakages in building envelopes. The advantage of ultrasound technology is that the corresponding wavelengths are small enough to penetrate small openings and that disturbing background noise is usually low. Moreover, the frequencies are above the human threshold of hearing; hence, working and living inside the building would be affected less by the measurement than by a blower door test or leakage detection with audible sound. To examine the suitability of this technology, we use an experimental setup of ultrasound microphones and a speaker in a test chamber. Within this setup, we measured different hole sizes and assessed whether they could be detected using ultrasonic frequency swept signals.

We introduce a novel technique that speeds up the computation of a frequency sweep or some parametric change of material properties—assumed uniform over the entire domain—around a nominal value in electroquasi-static problem or magnetoquasi-static problem. In place of using the usual practice of solving the complex systems arising at each frequency and at each material parameter value independently, our technique requires only one factorization of a real, symmetric, and positive definite matrix. The solution at each frequency and each value of material parameter is, then, found with a few back-substitutions only. The obtained speedup is sensible and the implementation is straightforward, showing the usefulness of the proposed technique in practical applications.

One of the main drawbacks of crumb rubber modified bitumen (CRMB) is the storage stability issue. The storage instability of CRMB impedes its further application. This study aims to develop a robust methodology to evaluate the storage stability of CRMB binders using both mechanical and morphological tests. The effects of rubber contents (0, 5%, 10%, 15%, 22% by weight of bitumen) and different non-foaming warm-mix additives (wax-based and chemical-based additives) on the storage stability of CRMB were investigated. Laboratory tests were also performed on the constituents of CRMB to have a deep understanding of the mechanism of storage instability. Standard tube separation tests were conducted on different binders. Both rheological tests and X-ray computed tomography (CT) scan tests were performed on the binder samples collected from different parts of the tube test. Separation indices were developed based on the difference in mechanical property and rubber content from the tube samples respectively. Results show that CRMB with a higher rubber content is more storage stable than that with a lower rubber content. The addition of warm-mix additives is detrimental to the storage stability of the studied CRMB. Rheological tests were performed on the individual constituents of CRMB (i.e., bitumen phase and rubber phase) to understand better the dynamic asymmetry potentially existing within the unstable CRMB binder. Results show that the residual bitumen becomes stiffer while the swollen rubber becomes softer after interaction because of the preferential absorption of light components of bitumen by rubber. The dynamic asymmetry existing between the bitumen phase and the rubber phase of CRMB results in storage instability. When the bitumen phase has similar dynamic properties as the rubber phase, the resulted binder system will be stable. It is possible to manipulate raw material properties and interaction conditions to achieve the desired crossover between two phases of CRMB and hence obtain a storage-stable CRMB blend.

New applications of non-destructive techniques (NDT) with ultrasonic tests (attenuation and velocity by means of ultrasonic frequency sweeps) have been developed for the characterization of fibre-reinforced cementitious composites. According to new lines of research on glass-fibre reinforced cement (GRC) matrix modification, two similar GRC composites with high percentages of fly ash and different water/binder ratios will be studied. Conventional techniques have been used to confirm their low Ca(OH)(2) content (thermogravimetry), fibre integrity (Scanning Electron Microscopy), low porosity (Mercury Intrusion Porosimetry) and good mechanical properties (compression and four points bending test). Ultrasound frequency sweeps allowed the estimation of the attenuation and pulse velocity as functions of frequency. This ultrasonic characterization was correlated successfully with conventional techniques. (C) 2015 Elsevier B.V. All rights reserved., This work has been supported by the Government of Spain under Grant TEC2011-23403 01/01/2012

Magento-rheological Fluid (MRF) and Shear Thickening Fluid (STF) have separately attracted considerable interest due to their fast and reversible response to an external magnetic field or an abrupt shearing loading. In this paper we fabricated a combined phase of Magento-rheological Shear Thickening Fluid (MRSTF) such that it has an MR and a shear thickening effect. To fabricate it, 14 nm primary size fumed silica particles were suspended in ethylene glycol to form a 25% by weight fraction of STF base. Carbonyl iron particles (3-5 μm) were then mixed with the STF base to obtain four MRSTF samples with weight fractions of 5%, 10%, 20%, and 30%. The viscoelastic properties of all four samples, namely their steady state and dynamic behaviour, were investigated with a parallel-plate rheometer. The relevance of the dynamic behaviour to the stress amplitude, frequency, and external magnetic field were investigated and discussed. MRSTFs behave like linear viscoelastic materials for a small range of stress amplitudes, but at large stress amplitudes they are non-linear viscoelastic or viscoplastic, where the storage modulus gradually decreases with the stress amplitude. Within the linear viscoelastic range of shear stress, MRSTFs behave with linear viscoelastic properties as the frequency increases. MRSTFs also exhibit features of both components, but are more prone to MRF with the inception of external field excitations.