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Early detection of SARS-CoV-2 using molecular techniques is paramount to the fight against COVID-19. Due to its high sensitivity and specificity, RT-qPCR is the “gold standard” method for this purpose. However, its technical requirements, processing time and elevated costs hamper its use towards massive and timely molecular testing for COVID-19 in rural and socioeconomically deprived areas of Latin America. The advent and rapid evolution of CRISPR-Cas technology has boosted the development of new pathogen detection methodologies. Recently, DETECTR -a combination of isothermal RT-LAMP amplification and Cas12a-mediated enzymatic detection-has been successfully validated in the Netherlands and the USA as a rapid and low-cost alternative to RT-qPCR for the detection of SARS-CoV-2 from nasopharyngeal swabs. Here, we evaluated the performance of RCSMS, a locally adapted variant of DETECTR, to ascertain the presence of SARS-CoV-2 in saliva samples from 276 patients in two hospitals in Lima, Perú (current status over a total of 350 samples). We show that a low-cost thermochemical treatment with TCEP/EDTA is sufficient to inactivate viral particles and cellular nucleases in saliva, eliminating the need to extract viral RNA with commercial kits, as well as the cumbersome nasopharyngeal swab procedure and the requirement of biosafety level 2 laboratories for molecular analyses. Our clinical validation shows that RCSMS detects up to 5 viral copies per reaction in 40 min, with sensitivity and specificity of 93.8% and 99.0% in the field, respectively, relative to RT-qPCR. Since CRISPR-Cas biosensors can be easily reprogrammed by using different guide RNA molecules, RCSMS has the potential to be quickly adapted for the detection of new SARS-CoV-2 variants. Notably, estimation of its negative and positive predictive values suggests that RCSMS can be confidently deployed in both high and low prevalence settings. Furthermore, our field study validates the use of lateral flow strips to easily visualize the presence of SARS-CoV-2, which paves the way to deploy RCSMS as a “point of care” test in environments with limited access to state-of-the-art diagnostic laboratories. In sum, RCSMS is a fast, efficient and inexpensive alternative to RT-qPCR for expanding COVID-19 testing capacity in low- and middle-income countries.

Phased-array radars rely heavily on correct phase calibration for proper beam steering. The calibration algorithms must be robust in order to be able to calibrate under very noisy conditions, while fast enough to enable on-the-fly calibration during operation. The current methods in the literature are either robust or fast. We propose a new algorithm based on the Element-wise Time Offsetting (ETO) and Multi-Element Phase Toggle (MEP) algorithms. Simulation results show that the proposed algorithm is as robust as MEP and 4 times faster.

This paper presents the implementation of digital image processing algorithms on Toradex’s Colibri IMX6 module and Iris carrier board. These algorithms will be used for the extraction, detection, and recognition of optical marks on digital images. Images will be obtained from an academic evaluation booklet through a webcam. Likewise, the computer will control an electrical/mechanical enclosure that stores and transports the evaluation booklets to be registered. The system proposed responds to the need to increase the efficiency of the grade recording process as previously designed for the Academic Coordination Department of the San Martin de Porres University’s School of Engineering and Architecture.

The Brazilian Digital Television System, based on ISDB-Tb, is currently using the 700 MHz band. This frequency band is ideal for LTE due to its large area coverage and lower implementation costs for service providers. This chapter aims to demonstrate the technical feasibility of broadcasting Digital TV multimedia content over LTE Broadcast in a similar way ISDB-Tb broadcasts using the Brazil Channels and GSM Channel broadcast profiles by comparing the bit error rate over a set of different SNR scenarios.

One of the major problems in power distribution networks is abnormal heating associated with high resistance or excessive current flow, in which some of the affected components include three-phase transformers, switches, connectors, fuses, etc. Utility Pole detection aids in the classification of these affected components; thus, the importance of its study. In this work, we propose a method to detect the utility poles using a database of images obtained from Google Maps for the region of Campinas/SP. The Bag of Visual Words (BoVW) method was used to classify the two classes (those that are utility poles and those that are not utility poles), and know if the sub-image obtained belongs to a utility pole class.

Presents the assessment of 16 FM stations cover-age held in the metropolitan region of Sao Paulo, pointing methodologies for prediction and measurement adopted by Anatel, analyzing the coverage gaps and showing, by simulations, the variations that the installation and operation features can causing to the coverage of a station, directly linked to the quality of service. The installation can be adjusted in order to compensate the attenuation caused by the terrain, so that it can contribute to the improvement in performance of the coverage of broadcasting stations.

One of the very useful techniques in Image Processing is the 2D Gaussian Filter, especially when smoothing images. However, the implementation of a 2D Gaussian Filter requires heavy computational resources, and when it comes down to real-time applications, efficiency in the implementation is vital. Floating-point math represents an obstacle for this, as its implementation requires a large amount of computational power in order to achieve real-time image processing. On the other hand, a fixed-point approach is much more suitable; implementation of a 2D Gaussian Filter in FPGA using fixed-point arithmetic provides efficiency in the processing and reduction in computational costs. The purpose of this study is to present the FPGA resource usage for different sizes of Gaussian Kernel; to provide a comparison between fixed-point and floating point implementations; and to define the amount of bits are necessary to use in order to have a Root Mean Square Error (RMSE) below 5%.

The Internet of Things (IoT) is spreading rapidly towards creating smart environments. Wireless sensor networks (WSN) are among the most popular applications discussed in IoT literature, with most of them considering many forms of wireless mesh communications. One of the most available and popular wireless technologies for short-range operations (yet not designed for mesh) is Bluetooth. Literature shows some studies on mesh networks BLE, based on Bluetooth 4.1 (which supports Master/Slave Multirole). Those approaches require more powerful hardware than a simple wireless sensor peripheral. Nonetheless, none address dynamic address allocation and topology mapping for BLE. We propose a new autoconfiguring dynamic address allocation scheme for a BLE Ad-Hoc network, and a network map discovery mechanism that does not require role changing, compatible with BLE 4.0 or later versions.