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Medicinal plants hold significant cultural significance and play a crucial role in the advancement of potentially safe drugs for the therapy of disease worldwide. Pennisetum purpureum or elephant grass has been used for traditional medications in Indonesia without understanding the phytochemicals of those plants. Herein, our report revolves around the qualitative and quantitative examination of phytochemical components, optical properties, antioxidants, and antibacterial assessments of solvent fractions derived from Pennisetum purpureum leaf. The Pennisetum purpureum leaf was successfully soaked with ethanol, n-hexane, and chloroform. The study aimed to assess the total phenolic content (TPC), total flavonoid content (TFC), and total alkaloid content (TAC) within different of extracts. The optical properties of extract were analyzed by absorption light and photoluminescent. Moreover, evaluation of antioxidant activities of extracts through DPPH free radical scavenging and FRAP assays, followed by an evaluation of their effectiveness in antibacterial therapy against different bacterial strains. The qualitative and quantitative phytochemical of Pennisetum purpureum presented as highest in ethanol TPC (85.5 mg GAE/g extracts), TFC (87.9 mg QE/g extracts), and TAC (86.2 mg ATE/g extracts) as compared to other solvents extract. Pennisetum purpureum extract had antioxidant capacity against DPPH radical and FRAP assay. Furthermore, each of the samples displayed antibacterial effectiveness that was dependent on the dosage towards different strains of bacteria. Our findings clearly demonstrated that Pennisetum purpureum leaf extracts grown in Indonesia containing alkaloid, flavonoid, glycoside, saponin, steroids, tannin, and terpenoids that support its capability as antioxidant and antibacterial.

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Automatic measurements via image processing can accelerate measurements and provide comprehensive evaluations of mechanical parts. This paper presents a comprehensive approach to automating evaluations of planar dimensions in mechanical parts, providing significant advancements in terms of cost-effectiveness, accuracy, and repeatability. The methodology employed in this study utilizes a configuration comprising commonly available products in the industrial computer vision market, therefore enabling precise determinations of external contour specifications for mechanical components. Furthermore, it presents a functional prototype for making planar measurements by incorporating an improved subpixel edge-detection method, thus ensuring precise image-based measurements. The article highlights key concepts, describes the measurement procedures, and provides comparisons and traceability tests as a proof of concept for the system. The results show that this vision system did achieve suitable precision, with a mean error of 0.008 mm and a standard deviation of 0.0063 mm, when measuring gauge blocks of varying lengths at different heights. Moreover, when evaluating a circular sample, the system resulted in a maximum deviation of 0.013 mm, compared to an alternative calibrated measurement machine. In conclusion, the prototype validates the methods for planar dimension evaluations, highlighting the potential for enhancing manual measurements, while also maintaining accessibility. The presented system expands the possibilities of machine vision in manufacturing, especially in cases where the cost or agility of current systems is limited.

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The development of visual sensors for traffic analysis can benefit from mimicking two fundamental aspects of the visual system of crabs: their panoramic vision and their visual processing strategy adapted to a flat world. First, the use of omnidirectional cameras in urban environments allows for analyzing the simultaneous movement of many objects of interest over broad areas. This would reduce the costs and complications associated with infrastructure: installation, synchronization, maintenance, and operation of traditional vision systems that use multiple cameras with a limited field of view. Second, in urban traffic analysis, the objects of interest (e.g. vehicles and pedestrians) move on the ground surface. This constraint allows the calculation of the 3D trajectory of the vehicles using a single camera without the need to use binocular vision techniques.The main contribution of this work is to show that the strategy used by crabs to visually analyze their habitat (monocular omnidirectional vision with the assumption of a flat world ) is useful for developing a simple and effective method to estimate the speed of vehicles on long trajectories in urban environments. It is shown that the proposed method estimates the speed with a root mean squared error of 2.7 km h-1.

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Visualizing two variables in the fluid flow requires a complex optical system to fulfill such a purpose. Furthermore, in these applications, measuring the temperature fields of the fluid is sometimes necessary. In this work, we use a color digital camera to record in one snapshot shadowgraph and two direction sensitivity Schlieren images. Furthermore, the Schlieren images obtained are used to measure temperature fields. The optical system, as main components, employs an rgb Light Emitting Diode (LED), two knife edges represented by shortpass and longpass ultra-thin filters, and a color digital camera. The results of this study show that shadowgraph images are contaminated with the crosstalk effect, and correction against it was applied. On the other hand, the reached resolution of the optical system to measure temperature values is approximately one degree.

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Different technologies can acquire data for gait analysis, such as optical systems and inertial measurement units (IMUs). Each technology has its drawbacks and advantages, fitting best to particular applications. The presented multi-sensor human gait dataset comprises synchronized inertial and optical motion data from 25 participants free of lower-limb injuries, aged between 18 and 47 years. A smartphone and a custom micro-controlled device with an IMU were attached to one of the participant's legs to capture accelerometer and gyroscope data, and 42 reflexive markers were taped over the whole body to record three-dimensional trajectories. The trajectories and inertial measurements were simultaneously recorded and synchronized. Participants were instructed to walk on a straight-level walkway at their normal pace. Ten trials for each participant were recorded and pre-processed in each of two sessions, performed on different days. This dataset supports the comparison of gait parameters and properties of inertial and optical capture systems, whereas allows the study of gait characteristics specific for each system.

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Particularities in the individuals' style of walking have been explored for at least three decades as a biometric trait, empowering the automatic gait recognition field. Whereas gait recognition works usually focus on improving end-to-end performance measures, this work aims at understanding which individuals' traces are more relevant to improve subjects' separability. For such, a manifold projection technique and a multi-sensor gait dataset were adopted to investigate the impact of each data source characteristics on this separability. Assessments have shown it is hard to distinguish individuals based only on their walking patterns in a subject-based identification scenario. In this setup, the subjects' separability is more related to their physical characteristics than their movements related to gait cycles and biomechanical events. However, this study's results also points to the feasibility of learning identity characteristics from individuals' walking patterns learned from similarities and differences between subjects in a verification setup. The explorations concluded that periodic components occurring in frequencies between 6 and 10 Hz are more significant for learning these patterns than events and other biomechanical movements related to the gait cycle, as usually explored in the literature.

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The present work reports the development of a biologically inspired analytical system known as Electronic Eye (EE), capable of qualitatively discriminating different tequila categories. The reported system is a low-cost and portable instrumentation based on a Raspberry Pi single-board computer and an 8 Megapixel CMOS image sensor, which allow the collection of images of Silver, Aged, and Extra-aged tequila samples. Image processing is performed mimicking the trichromatic theory of color vision using an analysis of Red, Green, and Blue components (RGB) for each image's pixel. Consequently, RGB absorbances of images were evaluated and preprocessed, employing Principal Component Analysis (PCA) to visualize data clustering. The resulting PCA scores were modeled with a Linear Discriminant Analysis (LDA) that accomplished the qualitative classification of tequilas. A Leave-One-Out Cross-Validation (LOOCV) procedure was performed to evaluate classifiers' performance. The proposed system allowed the identification of real tequila samples achieving an overall classification rate of 90.02%, average sensitivity, and specificity of 0.90 and 0.96, respectively, while Cohen's kappa coefficient was 0.87. In this case, the EE has demonstrated a favorable capability to correctly discriminated and classified the different tequila samples according to their categories.

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Optically pumped magnetometers (OPMs) have reached sensitivity levels that make them viable portable alternatives to traditional superconducting technology for magnetoencephalography (MEG). OPMs do not require cryogenic cooling and can therefore be placed directly on the scalp surface. Unlike cryogenic systems, based on a well-characterised fixed arrays essentially linear in applied flux, OPM devices, based on different physical principles, present new modelling challenges. Here, we outline an empirical Bayesian framework that can be used to compare between and optimise sensor arrays. We perturb the sensor geometry (via simulation) and with analytic model comparison methods estimate the true sensor geometry. The width of these perturbation curves allows us to compare different MEG systems. We test this technique using simulated and real data from SQUID and OPM recordings using head-casts and scanner-casts. Finally, we show that given knowledge of underlying brain anatomy, it is possible to estimate the true sensor geometry from the OPM data themselves using a model comparison framework. This implies that the requirement for accurate knowledge of the sensor positions and orientations a priori may be relaxed. As this procedure uses the cortical manifold as spatial support there is no co-registration procedure or reliance on scalp landmarks.

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Sandwich structures were fabricated by a vacuum deposition method using MPc (M = Cu, Zn), with a Tetrathiafulvalene (TTF) derivative, and Indium Tin Oxide (ITO) and aluminum electrodes. The structure and morphology of the deposited films were studied by IR spectroscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The absorption spectra of TTF derivative-MPc (M = Cu, Zn) thin films deposited at room temperature were recorded in the spectral range 200-1000 nm. The optical band gap of the thin films was determined from the (αhν)(1/2) vs. hν plot. The direct-current (DC) electrical properties of the glass/ITO/TTFderiv-MPc (M = Cu, Zn)/Al structures were also investigated. Changes in conductivity of the derivative-TTF-enriched Pc compounds suggest the formation of alternative paths for carrier conduction. At low voltages, forward current density obeys an ohmic I-V relationship; at higher voltages, conduction is mostly due to a space-charge-limited conduction (SCLC) mechanism.

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Este artigo procura apresentar os conceitos de agenciamento e phylum maquínico, concebidos por Gilles Deleuze e Felix Guattari, para sublinhar o silício dentro do agenciamento contemporâneo homem-natureza. O silício (Si), matéria de destaque da microeletrônica, torna-se matéria expressiva de uma ética e de uma estética próprias. Com o objetivo de cartografar as forças que se colocam em ação em alguns agenciamentos homem-silício, busca criar uma imagem-pensamento tributária de uma estética do silício, que exprime um modo de existência. Neste trajeto, estão cartografadas algumas linhas de sustentação de uma sociedade de controle e outras linhas que agem em ruptura com a mesma. Com a arte, na idade da informatização planetária, vislumbram-se linhas orientadas a uma nova processualidade criativa e singularizante, capazes de promover mudanças nos posicionamentos do homem por uma vida portadora de certos valores estéticos...

Este artículo presenta los conceptos de agenciamiento y phylum maquínico, concebidos por Gilles Deleuze y Felix Guattari, para subrayar el silicio dentro del agenciamiento contemporáneo hombre-naturaleza. El silicio (Si), resalte el campo de la microelectrónica, se convierte en materia expresiva de una ética y de una estética propias. Con el propósito de cartografiar las fuerzas que se ponen a la acción en algunos agenciamientos hombre-silicio, busca crear una imagen-pensamiento tributaria de una estética del silicio, que expresa un modo de existencia. En este camino, se asignan algunas líneas de sostentación de una sociedad de control y otras líneas que actúan en ruptura de la misma. Con el arte, a la edad de informatización planetaria, se vislumbran líneas orientadas a una nueva procesualidad creativa y singularizante, capaces de promover cambios en los posicionamientos del hombre por una vida portadora de ciertos valores estéticos...

In this article we introduce the concepts of arrangement and machinic phylum, created by Gilles Deleuze and Felix Guattari, to underline the silicon inside the contemporary arrangement Man-Nature. Silicon (Si), the highlight of microelectronics, becomes expressive subject of an ethics and an aesthetic. In order to map the forces in action in some arrangements Man-Silicon, we seek to create a thought-image of a silicon aesthetic, which expresses a mode of existence. In this way, we map a few support lines of a control society and others which act in breach with that. With art, at the age of planetary computerization, we find lines oriented to a new creative and singularity process, able to promote changes in man's positions, toward to another mode of existence carried with some aesthetic values...

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