Does AIDS involve some collusion by the neuro-immune system because of positive learning of the disarmament strategy?

International audienceKorzybski's general semantics recommends considering living beings as organisms-as-a-whole in their environment. Our cognitive abilities, specific to the human species, have thus to be taken into account. In this framework we establish a semantic similarity between particular stressful events of the 20th century and AIDS in which the immune-deficiency-caused is semiotically seen as a biological state of disarmament of the organism. It then appears that : - at the extent of the worldwide propagation of the pandemic, the disarmament concept was valued as a hopefully survival strategy because of the media coverage of the Cold War and of the associated threat of nuclear annihilation, - at the extent of the African regions of origin of the different HIV strains, the best survival behavior of slaves fits the disarmament concept. These observations suggest that AIDS could benefit from some collusion by the neuro-immune system because of positive learning of the semiotic concept of disarmament, thus making the terrain favorable to the germ in response to intense stress. The disease would then result from a conditioning process based on semiotics and involve some confusion at the level of the unconscious cognitive system between disarmament toward outside the body and disarmament toward inside the body. This hypothesis is discussed within a multidisciplinary perspective considering the specificities of our modern lifestyles, the cybernetic ability of signs to control metabolism and behavior, and the recent advances of epigenetics and cognition sciences. This hypothesis may explain the multiple cross-species transmissions of the immunodeficiency virus into humans during the 20th century. Further research is suggested for evaluating this hypothesis

Fase espectral: de las ideas básicas a la aplicación en un video de la resonancia de un diapasón

Whereas graduated students are usually familiar with Fourier spectra, the spectral phase remains often mysterious to them. This paper proposes a “hands on.approach of discrete Fourier transform (DFT) and spectral phase. In a first part, basics of DFT are explored through elementary simulations. The variation of digital parameters allows the identification of sampled frequencies las well as their relation with the size of the sampled window. The significance of the spectrum phase is also illustrated experimentally to demonstrate the useful relationship between a displacement and the spectral phase. In a second part, these properties are put in application for the characterization of tuning-fork resonance by means of video-rate analysis of the spectral phase. Experimental hardware is reduced to elementary devices and remains affordable while involving all aspects of a measurement chain. The proposed progression constitutes a practical approach to discrete Fourier transform and spectral phase properties. At the end, the resonance curve of a tuning-fork is recorded in only a few minutes. The Shannon sampling theorem as well as the uncertainty relation linking the resolutions achieved in the direct and reciprocal domains, are also considered practically throughout this work.Mientras que los estudiantes graduados están familiarizados con el espectro de Fourier, la fase espectral a menudo se mantiene misteriosa. Este artículo propone una aproximación practica a la Transformada de Fourier Discreta (TFD) y a la fase espectral. En una primera parte, se exploran las bases de TFD mediante simulaciones elementales. La variación de parámetros digitales permite la identificación de frecuencias de muestreo y su relación con el tamaño de la ventana muestreada. La importancia del espectro de fase también se ilustra experimentalmente para demostrar la utilidad de la relación existente entre un desplazamiento y la fase espectral. En la segunda parte, estas propiedades son puestas en práctica caracterizando la resonancia de un diapasón mediante el análisis de la tasa de video de la fase espectral. El material experimental implicado en todos los aspectos de las medidas se reduce a unos dispositivos elementales y económicos. La propuesta constituye un acercamiento practico a Transformada de Fourier Discreta y las propiedades de la fase espectral. Para finalizar, se registra la curva de resonancia de un diapasón en sólo unos minutos. El teorema del muestreo de Shannon, así como la relación de incertidumbre que liga las resoluciones alcanzadas en los dominios directos y recíprocos también son considerados prácticamente en todas las partes de este trabajo

Optical Coherence Spectro-Tomography by all-Optical Depth-Wavelength analysis

Current spectroscopic optical coherence tomography (OCT) methods rely on a posteriori numerical calculation. We present an alternative for accessing optically the spectroscopic information in OCT, i.e. without any post-processing, by using a grating based correlation and a wavelength demultiplexing system. Conventional A-scan and spectrally resolved A-scan are directly recorded on the image sensor. Furthermore, due to the grating based system, no correlation scan is necessary. In the frame of this paper we present the principle of the system as well as first experimental results

Characterization and Compensation of XY Micropositioning Robots using Vision and Pseudo-Periodic Encoded Patterns.

International audienceAccuracy is an important issue for microrobotic applications. High accuracy is usually a necessary condition for reliable system performance. However there are many sources of inaccuracy acting on the microrobotic systems. Characterization and compensation enable reduction of the systematic errors of the micropositioning stages and improve the positioning accuracy. In this paper, we propose a novel method based on vision and pseudo-periodic encoded patterns to characterize the position-dependent errors along XY stages. This method is particularly suitable for microscale motion characterization thanks to its high range-to-resolution ratio and avoidance of camera calibration. Based on look-up tables and interpolation techniques, we perform compensation and get improved accuracy. The experimental results show an accuracy improved by 84% for square tracking and by 68% for random points reaching (respectively from 22 μm to 3.5 μm and from 22 μm to 7 μm)

A Fluorescent Kinase Inhibitor that Exhibits Diagnostic Changes in Emission upon Binding

The development of a fluorescent LCK inhibitor that exhibits favourable solvatochromic properties upon binding the kinase is described. Fluorescent properties were realised through the inclusion of a prodan-derived fluorophore into the pharmacophore of an ATP-competitive kinase inhibitor. Fluorescence titration experiments demonstrate the solvatochromic properties of the inhibitor, in which dramatic increase in emission intensity and hypsochromic shift in emission maxima are clearly observed upon binding LCK. Microscopy experiments in cellular contexts together with flow cytometry show that the fluorescence intensity of the inhibitor correlates with the LCK concentration. Furthermore, multiphoton microscopy experiments demonstrate both the rapid cellular uptake of the inhibitor and that the two-photon cross section of the inhibitor is amenable for excitation at 700 nm

Posicionamiento visual con resolución subpixel de objetos marcados que se desplazan en un plano: conceptos básicos y aplicaciones

Vision is a convenient tool for position measurements. In this paper, we present several applications in which a reference pattern can be defined on the target for a priori knowledge of image features and further optimization by software. Selecting pseudoperiodic patterns leads to high resolution in absolute phase measurements. This method is adapted to position encoding of live cell culture boxes. Our goal is to capture each biological image along with its absolute highly accurate position regarding the culture box itself. Thus, it becomes straightforward to find again an already observed region of interest when a culture box is brought back to the microscope stage from the cell incubator where it was temporarily placed for cell culture. In order to evaluate the performance of this method, we tested it during a wound healing assay of human liver tumor-derived cells. In this case, the procedure enabled more accurate measurements of the wound healing rate than the usual method. It was also applied to the characterization of the in-plane vibration amplitude from a tapered probe of a shear force microscope. The amplitude was interpolated by a quartz tuning fork with an attached pseudo-periodic pattern. Nanometer vibration amplitude resolution is achieved by processing the pattern images. Such pictures were recorded by using a common 20x magnification lens.La visión es una herramienta conveniente para mediciones de posición. En este artículo, presentamos aplicaciones en las que un patrón de referencia puede ser adherido al objeto de interés. Ésto permite tener un conocimiento a priori de las características de la imagen y así poder optimizar el software. Como patrón de referencia se usan patrones pseudo-periódicos, los cuales permiten una alta resolución en las mediciones de fase absoluta. El método es adaptado para codificar la posición de soportes de cultivos celulares, con el fin de documentar cada imagen biológica registrada con su posición absoluta. Por lo tanto, resulta sencillo encontrar de nuevo una región de interés, observada previamente, cuando una caja de cultivo es traída de nuevo al microscopio luego de estar en una incubadora. Para evaluar el método, éste se utilizó durante un ensayo de “cicatrización de herida” de un cultivo celular derivado de tumores hepáticos. En este caso, el método permite obtener mediciones más precisas de la tasa de “cicatrización”, comparado a los resultados obtenidos con el método usual. El método propuesto también se aplica a la caracterización de la amplitud de vibración en el plano de una sonda de un microscopio de fuerza atómica. La amplitud fue interpolada por medio de un diapasón de cuarzo al cual se la adhirió un patrón pseudo-periódico. A partir del procesamiento de las imágenes del patrón, se logra obtener resolución nanométrica en la medida de la amplitud de la vibración. Estas imágenes fueron obtenidas con un microscopio óptico con magnificación 20x

Fast contactless vibrating structure characterization using real time field programmable gate array-based digital signal processing: Demonstrations with a passive wireless acoustic delay line probe and vision

International audienceVibrating mechanical structure characterization is demonstrated using contactless techniques best suited for mobile and rotating equipments. Fast measurement rates are achieved using Field Programmable Gate Array (FPGA) devices as real-time digital signal processors. Two kinds of algorithms are implemented on FPGA and experimentally validated in the case of the vibrating tuning fork. A first application concerns in-plane displacement detection by vision with sampling rates above 10 kHz, thus reaching frequency ranges above the audio range. A second demonstration concerns pulsed-RADAR cooperative target phase detection and is applied to radiofrequency acoustic transducers used as passive wireless strain gauges. In this case, the 250 ksamples/s refresh rate achieved is only limited by the acoustic sensor design but not by the detection bandwidth. These realizations illustrate the efficiency, interest, and potentialities of FPGA-based real-time digital signal processing for the contactless interrogation of passive embedded probes with high refresh rates

Posicionamiento visual con resolución subpixel de objetos marcados que se desplazan en un plano: conceptos básicos y aplicaciones

Vision is a convenient tool for position measurements. In this paper, we present several applications in which a reference pattern can be defined on the target for a priori knowledge of image features and further optimization by software. Selecting pseudoperiodic patterns leads to high resolution in absolute phase measurements. This method is adapted to position encoding of live cell culture boxes. Our goal is to capture each biological image along with its absolute highly accurate position regarding the culture box itself. Thus, it becomes straightforward to find again an already observed region of interest when a culture box is brought back to the microscope stage from the cell incubator where it was temporarily placed for cell culture. In order to evaluate the performance of this method, we tested it during a wound healing assay of human liver tumor-derived cells. In this case, the procedure enabled more accurate measurements of the wound healing rate than the usual method. It was also applied to the characterization of the in-plane vibration amplitude from a tapered probe of a shear force microscope. The amplitude was interpolated by a quartz tuning fork with an attached pseudo-periodic pattern. Nanometer vibration amplitude resolution is achieved by processing the pattern images. Such pictures were recorded by using a common 20x magnification lens.La visión es una herramienta conveniente para mediciones de posición. En este artículo, presentamos aplicaciones en las que un patrón de referencia puede ser adherido al objeto de interés. Ésto permite tener un conocimiento a priori de las características de la imagen y así poder optimizar el software. Como patrón de referencia se usan patrones pseudo-periódicos, los cuales permiten una alta resolución en las mediciones de fase absoluta. El método es adaptado para codificar la posición de soportes de cultivos celulares, con el fin de documentar cada imagen biológica registrada con su posición absoluta. Por lo tanto, resulta sencillo encontrar de nuevo una región de interés, observada previamente, cuando una caja de cultivo es traída de nuevo al microscopio luego de estar en una incubadora. Para evaluar el método, éste se utilizó durante un ensayo de “cicatrización de herida” de un cultivo celular derivado de tumores hepáticos. En este caso, el método permite obtener mediciones más precisas de la tasa de “cicatrización”, comparado a los resultados obtenidos con el método usual. El método propuesto también se aplica a la caracterización de la amplitud de vibración en el plano de una sonda de un microscopio de fuerza atómica. La amplitud fue interpolada por medio de un diapasón de cuarzo al cual se la adhirió un patrón pseudo-periódico. A partir del procesamiento de las imágenes del patrón, se logra obtener resolución nanométrica en la medida de la amplitud de la vibración. Estas imágenes fueron obtenidas con un microscopio óptico con magnificación 20x

Fast Autofocusing using Tiny Transformer Networks for Digital Holographic Microscopy

The numerical wavefront backpropagation principle of digital holography confers unique extended focus capabilities, without mechanical displacements along z-axis. However, the determination of the correct focusing distance is a non-trivial and time consuming issue. A deep learning (DL) solution is proposed to cast the autofocusing as a regression problem and tested over both experimental and simulated holograms. Single wavelength digital holograms were recorded by a Digital Holographic Microscope (DHM) with a 10$\mathrm{x}$ microscope objective from a patterned target moving in 3D over an axial range of 92 $\mu$m. Tiny DL models are proposed and compared such as a tiny Vision Transformer (TViT), tiny VGG16 (TVGG) and a tiny Swin-Transfomer (TSwinT). The experiments show that the predicted focusing distance $Z_R^{\mathrm{Pred}}$ is accurately inferred with an accuracy of 1.2 $\mu$m in average in comparison with the DHM depth of field of 15 $\mu$m. Numerical simulations show that all tiny models give the $Z_R^{\mathrm{Pred}}$ with an error below 0.3 $\mu$m. Such a prospect would significantly improve the current capabilities of computer vision position sensing in applications such as 3D microscopy for life sciences or micro-robotics. Moreover, all models reach state of the art inference time on CPU, less than 25 ms per inference

Dispositif ultra-léger de caractérisation mécanique de la peau humaine in vivo en extensiométrie uniaxiale (S13)

L'étude des propriétés mécaniques de la peau humaine in vivo est une étape utile dans l'optimisation des interventions chirurgicales. Pour évaluer les caractéristiques de ce tissu biologique complexe, un dispositif a été développé au sein de l'institut FEMTO-ST, il est composé d'un extensiomètre ultra-léger piloté par une application, elle-même comportant un éditeur de consigne ainsi qu'une interface de commande. Afin de valider ce dispositif, des tests ont été réalisés pour obtenir la réponse de celui-ci à différents types de sollicitations en extension uniaxiale, ainsi qu'une comparaison avec la réponse obtenue d'une machine de traction standard. Cette comparaison a montré une forte similarité entre les deux appareils de mesure. Grâce à sa taille, son poids et sa portabilité, le dispositif présenté a mis en évidence le comportement hyperélastique et visqueux du tissu cutané lors de tests réalisés in vivo en différentes localisations corporelles.   The analysis of the mechanical properties of human skin in vivo is an essential parameter for the optimization of surgical operations in terms of cutaneous tissues. This paper presents an experimental device that was developed at FEMTO-ST institute for evaluating the skin response to different loadings. The ultra-light extensometer developed was tested in a uniaxial extension on a phantom material. The results obtained were successfully compared with those of a conventional tensile test device. The user-friendly interface allows the definition of diverse load and discharge sequences. The results of the tests on human subjects are consistent with the hyperelastic and viscous behavior of the cutaneous tissue in vivo. Thanks to its size, weight and stand-alone capabilities, the device is suited for local measurements in most of human body zones. This study provides an experimental tool for investigating human skin behavior in vivo. Further researches are being directed towards identifying the strain fields of human skin by means of a biaxial extensometer and an imaging module