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We present an analysis of the bandwidth of an asymmetric 8-beam Fourier grating as the beam multiplexer for a 4.7 THz local oscillator used in a heterodyne receiver. We take the grating designed for NASA GUSTO balloon observatory as an example to address the bandwidth question although it does not need to operate over a wide frequency range. By illuminating the grating at different frequencies from 4.445 to 5.045 THz, we simulated the changes of its performance in three aspects using COMSOL Multiphysics: diffraction efficiency, power uniformity, and the angular distribution of the output beams. These parameters can affect the coupling efficiency between the output beams of the grating and the beams of a mixer array. The bandwidth of the grating is found to be 230 GHz, corresponding to 4.9% of the operating frequency, which is sufficient for many applications.

We have studied THz heterodyne detection in sub-micrometer MgB2 hot electron bolometer (HEB) mixers based on superconducting MgB2 films of [Formula: see text] (HEB-A), corresponding to a critical temperature ( Tc) of 33.9 K, and [Formula: see text] (HEB-B), corresponding to a [Formula: see text] of 38.4 K. We have measured a double sideband (DSB) receiver noise temperature of 2590 K for HEB-A and 2160 K for HEB-B at 1.6 THz and 5 K. By correcting for optical losses, both HEBs show receiver noise temperatures of ∼1600 K referenced to the front of anti-reflection (AR)-coated Si lenses. An intermediate frequency (IF) noise bandwidth of 11 GHz has been measured for both devices. The required local oscillator (LO) power is about 13 μW for both HEBs. We have also measured a DSB receiver noise temperature of 3290 K at 2.5 THz and 5 K but with an AR-coated lens optimized for 1.6 THz. Besides, we have observed a step-like structure in current voltage (IV) curves, which becomes weaker when the LO power increases and observable only in their differential resistance. Such a correlated structure appears also in the receiver output power as a function of voltage, which is likely due to electronic inhomogeneities intrinsic to the variations in the thickness of the MgB2 films. Different behavior in the IV curves around the low bias voltages, pumped with the same LO power at 1.6 and 5.3 THz, was observed for HEB-B, suggesting the presence of a high-energy σ-gap in the MgB2 film.

In the present study a single screen-printed carbon electrode (SPCE) and chemometric techniques were utilized for forensic differentiation of Brazilian American lager beers. To differentiate Brazilian beers at the manufacturer and brand level, the classification techniques: soft independent modeling of class analogy (SIMCA), partial least squares regression discriminant analysis (PLS-DA), and support vector machines discriminant analysis (SVM-DA) were tested. PLS-DA model presented an inconclusive assignment ratio of 20%. On the other hand, SIMCA models had a 0 inconclusive rate but an sensitivity close to 85%. While the non-linear technique (SVM-DA) showed an accuracy of 98%, with 95% sensitivity and 98% specificity. The SPCE-SVM-DA technique was then used to distinguish at brand level two highly frauded beers. The SPCE coupled with SVM-DA performed with an accuracy of 97% for the classification of both brands. Therefore, the proposed electrochemicalsensor configuration has been deemed an appropriate tool for discrimination of American lager beers according to their producer and brands.

A low-cost and disposable graphene polylactic (G-PLA) 3D-printed electrode modified with gold particles (AuPs) was explored to detect the cDNA of SARS-CoV-2 and creatinine, a potential biomarker for COVID-19. For that, a simple, non-enzymatic electrochemical sensor, based on a Au-modified G-PLA platform was applied. The AuPs deposited on the electrode were involved in a complexation reaction with creatinine, resulting in a decrease in the analytical response, and thus providing a fast and simple electroanalytical device. Physicochemical characterizations were performed by SEM, EIS, FTIR, and cyclic voltammetry. Square wave voltammetry was employed for the creatinine detection, and the sensor presented a linear response with a detection limit of 0.016 mmol L−1. Finally, a biosensor for the detection of SARS-CoV-2 was developed based on the immobilization of a capture sequence of the viral cDNA upon the Au-modified 3D-printed electrode. The concentration, immobilization time, and hybridization time were evaluated in presence of the DNA target, resulting in a biosensor with rapid and low-cost analysis, capable of sensing the cDNA of the virus with a good limit of detection (0.30 µmol L−1), and high sensitivity (0.583 µA µmol−1 L). Reproducible results were obtained (RSD = 1.14%, n = 3), attesting to the potentiality of 3D-printed platforms for the production of biosensors.

In this article, we present a study that aimed to investigate what has been produced for pedagogical practices addressed to the early years by research carried out in the Professional Masters (MP) of the Graduate Program in Scientific, Educational and Technological Training (PPGFCET), for the selection and analysis, based on qualitative research with a phenomenological approach, of dissertations and respective educational products published since the creation of the aforementioned program. It is concluded that most of these products present training elements for teaching, in a dynamic of knowledge that develops substantial forms by involving those who are training and those who are graduating. Thus, the notion of product as an end is broadened, a result of a research action to be applied and replicated to produce as a cover-up, with a view to the possibilities of becoming these products, and, with that, formative possibilities for all involved. Neste artigo, expomos um estudo que teve por meta investigar o que vem sendo produzido para as práticas pedagógicas endereçadas aos anos iniciais pelas pesquisas desenvolvidas no Mestrado Profissional (MP) do Programa de Pós-Graduação em Formação Científica, Educacional e Tecnológica (PPGFCET), pela seleção e análise, com base na pesquisa qualitativa de abordagem fenomenológica, de dissertações e respectivos produtos educacionais publicados desde a criação do referido programa. Conclui-se que a maioria desses produtos apresentam elementos de formação para o ensino, numa dinâmica de conhecimento que desenvolve formas substancializadas ao envolver quem está a formar e quem está se formando. Assim, amplia-se a noção de produto como um fim, um resultado de uma ação de pesquisa a ser aplicada e replicada para um produzir como desencobrimento, com vistas às possibilidades de vir a ser desses produtos, e, com isso, possibilidades formativas a todos os envolvidos.

FPGAs are gaining popularity as the target of choice for the efficient implementation of Deep Neural Networks (DNNs) approaches. Modern SoCs with integrated FPGAs have low-power on-chip processors and sufficient interfaces to accommodate the most commonly deployed Internet of Things (IoT) devices. However, developing DNN hardware accelerators using integrated FPGAs remains a complicated task due to the complexity of reconfigurable computing and limited hardware resources on embedded devices. In addition, it is necessary to master High-Level Synthesis tools (HLS) and their hidden philosophy driving RTL design. This paper presents our Python framework to fully customize and automate the generation and deployment of FPGA-based DNN topologies for Edge Computing. Our framework environment, Jupyter Notebooks, allows users to customize their desired hardware DNN and its related applications on Xilinx’s Pynq boards. Subsequently, the framework automatically generates TCL (Tool Command Language) scripts driving HLS tools on the host server or cloud. Once the desired FPGA-based architecture is generated, the framework retrieves the bitstream to configure the FPGA. Therefore, the user can deploy this bitstream to accelerate any Python application that performs the same DNN model. The experimental results show that our framework can speed up 59.8× a 784-32-32-10 topology, while the power consumption is less than 0.266W.

Azathioprine is an immunosuppressive drug for several inflammatory disorders. Due to its clinical relevance, to explore the solid-state properties for excipient compatibility in the product quality review process is essential. Fourier transform infrared spectroscopy, powder X-ray diffraction and thermal analysis (thermogravimetry/derivative thermogravimetry (TG/DTG), differential thermal analysis (DTA), and differential scanning calorimetry (DSC)) were applied. The compatibility studies evidenced that starch pregelatinized, colloidal silicon dioxide, and talc are fully compatible with azathioprine. However, stearic acid, magnesium stearate, and mannitol are incompatible after heat supply at temperatures easily reached by industrial processing. The nonlinear Vyazovkin isoconversional treatment performed the kinetic study of the thermal degradation. The activation energies were determined to clarify the influence of each excipient on the thermal drug stability, an essential procedure in the pharmaceutical development, and all over the commercial live span, in Good Manufacturing Practices.

Large heterodyne receiver arrays (~100 pixel) allow astronomical instrumentations mapping more area within limited space mission lifetime. One challenge is to generate multiple local oscillator (LO) beams. Here, We succeeded in generating 81 beams at 3.86 THz by combining a reflective, metallic Fourier grating with an unidirectional antenna coupled 3rd-order distributed feedback (DFB) quantum cascade laser (QCL). We have measured the diffracted 81 beams by scanning a single pyroelectric detector at a plane, which is in the far field for the diffraction beams. The measured output beam pattern agrees well with a simulated result from COMSOL Multiphysics with respect to the angular distribution and power distribution among the 81 beams. We also derived the diffraction efficiency to be 94\pm 3\%, which is very close to what was simulated for a manufactured Fourier grating (97%). For an array of equal superconducting hot electron bolometer mixers, 64 out of 81 beams can pump the HEB mixers with similar power, resulting in receiver sensitivities within 10%. Such a combination of a Fourier grating and a QCL can create an LO with 100 beams or more, enabling a new generation of large heterodyne arrays for astronomical instrumentation. This paper is essentially a copy of our paper in Optics Express.

A phenomenological model for the description of the single and double diffractive excitation in $pp$ collisions at high energies is presented. Considering the Good -- Walker approach, we propose a model for the eigenstates of the scattering operator and for the treatment of the interaction between them, with the high energy behavior of the cross section driven by perturbative QCD. The behavior of the total, elastic, single and double diffractive cross sections are analyzed and predictions for the energies of Run 3 of the LHC and those of the Cosmic Rays experiments are derived. We demonstrate that the model describes the current data for the energy dependence of the cross sections. A comparison with the recent data for the $\rho$ parameter and the differential elastic cross section are also presented and shortcomings of the current model are discussed., Comment: 13 pages, 5 figures, 1 table. Improved version published in Physical Review D

Currently, school furniture used in preschool classrooms counts with a solid and functional design that has stayed practically invariant for the last 20 years, although it does not invite children to interact much with it. This furniture fills a great part of the classroom’s functional space, and it is normally destined to a specific use, which avoids that it was used at other moments of the day, or in other activity zones. Moreover, last tendencies relative to preschool classroom’s space organization demand more flexible layouts that allow a quick adaptation, which is impossible with traditional furniture. This work shows the result of the conceptual design of a new line of modular, foldable and stackable preschool furniture, destined for its use indoors in schools, kindergartens, or even at home, composed by a highchair, a desk and a chair. The design has been made following ergonomic, functional and easiness of assembly criteria, as well as the ones of health and safety. Finally, optimal materials have been selected, and the manufacturing cost of each product has been studied, in order to evaluate its competiveness.

The automotive industry is now extensively using multi-material structures to reduce vehicle weight. Joining these dissimilar materials effectively in a single structure demands the use of adhesive bonding, but the presence of stress concentrations leads to low mechanical performance. Mixed adhesive joints have been proposed as a solution for this issue, using two adhesives in the same joint, combining stiffness and flexibility on the same overlap, improving performance. This work focuses on the numerical modelling of the mechanical behaviour of these joints, using previously published experimental data for validation. The proposed models use cohesive laws with strain rate dependent data to simulate quasi-static and impact loads on several configurations of mixed adhesive joints, using four different adhesives. The models were able to predict the behaviour of most configurations under study, especially for the stiffer adhesives. The model was found to be less effective for modelling high ductility adhesives under impact.

Development of greener water treatment technologies is important for the production of safe drinking water and water security applications, such as decontamination. Chlorine assisted disinfection is common and economical, but can generate disinfection byproducts (DBPs) that may be of health concern. DBPs are formed due to the reaction of chlorine with naturally occurring organic and inorganic substances in water. Currently, various innovative technologies are being developed as alternative approaches for preventing DBPs during water treatment. In this study, we evaluated the effectiveness of a novel combination of high efficiency flow filtration and UV disinfection treatment system for the removal of Bacillus globigii (B. globigii) spores in water. The filtration system consists of a charged membrane filter (CMF) that not only helps to remove suspended particles but also reduces the impact of other impurities including bio organisms. In order to get most performance details, the CMF was evaluated at clean, half-life, and end of life (EOL) conditions along with 100% UV transmittance (UVT). In addition, the effectiveness of the UV system was evaluated as a stand alone system at 100% and 70% EOL intensity. The study was conducted at the US EPA's Test and Evaluation (T&E) Facility in Cincinnati, OH, using B. globigii, a surrogate for B. anthracis spores. This non-chemical environmentally-friendly CMF/UV combination system and the stand alone UV unit showed greater than 6.0 log removal of B. globigii during the tests.

In this paper, we consider the Good-Walker approach for the diffractive excitation and present an update of the Miettinen-Pumplin (MP) model for $pp/\overline{p}p$ collisions considering the recent LHC data for the total and elastic $pp$ cross sections. The behavior of the total, elastic, and diffractive cross sections is analyzed, and predictions for the energies of Run 3 of the LHC and those of the cosmic ray experiments are derived. Our results demonstrate that the MP model is able to describe the current data, and that it implies that the cross section for the diffraction excitation in $pp$ collisions is almost constant in the energy range probed by the LHC and slowly decreases at higher energies. Our results also indicate that the Pumplin bound is not reached at the LHC and cosmic ray energies. Moreover, the implications of the diffractive excitation in $pA$ collisions are discussed. In particular, the MP model, constrained by the $pp$ data, is used to derive the main quantities present in the treatment of the diffractive excitation in $pA$ collisions. Predictions for the total, elastic, and diffractive $pA$ cross sections are presented considering different nuclei. We demonstrate that the effect of fluctuations decreases at larger energies and heavier nuclei. The energy dependence of the diffractive excitation cross section in $pA$ collisions is estimated for different nuclei and compared with the predictions for the proton dissociation induced by photon interactions.

Energy efficiency is a growing concern for modern computing, especially for HPC due to operational costs and the environmental impact, considering that processors have an important role in this energy consumption. In this work, we propose a methodology to find energy-optimal frequency and number of active cores to run single-node HPC applications using an application-agnostic power model of the architecture and an architecture-aware performance model of the application. We characterize the application performance using machine learning, specifically the “Support Vector Regression” algorithm. Besides that, the power consumption is estimated by modeling CMOS dynamic and static power without knowledge of the application. So, The energy-optimal configuration is estimated by minimizing the product these two models outcomes, the power model and the performance model. Then, the final model can be used to find better frequency and number of cores to aim energy efficiency application execution. Results were obtained for four PARSEC applications and, with five different inputs shows that the proposed approach used substantially less energy when compared to the DVFS governor, in best cases and worst cases.

Inspired by the recent TOTEM data for the elastic proton -- proton ($pp$) scattering at $\sqrt{s} =$ 8 and 13 TeV, we update previous studies of the differential cross sections using the Phillips -- Barger (PB) model, which parametrizes the amplitude in terms of a small number of free parameters. We demonstrate that this model is able to describe the recent $pp$ data on a statistically acceptable way. Additionally, we perform separate fits of the $pp$ data for each center - of - mass energy and propose a parametrization for the energy dependence of the parameters present in the PB model. As a consequence, we are able to present the PB predictions for the elastic proton - proton cross section at $\sqrt{s} = 546$ GeV and $1.8$ TeV, which are compared with the existing antiproton -- proton ($\bar{p}p$) data. We show that the PB predictions, constrained by the $pp$ data, are not able to describe the $\bar{p}p$ data. In particular, the PB model predicts a dip in the differential cross section that is not present in the $\bar{p}p$ data. Such result suggests the contribution of the Odderon exchange at high energies., Comment: 6 pages, 4 tables, 2 figures, results updated, matches published version

Taking advantage of the growing number of cores in supercomputers to increase the scalability of parallel programs is an increasing challenge. Many advanced profiling tools have been developed to assist programmers in the process of analyzing data related to the execution of their program. Programmers can act upon the information generated by these data and make their programs reach higher performance levels. However, the information provided by profiling tools is generally designed to optimize the program for a specific execution environment, with a target number of cores and a target problem size. A code optimization driven towards scalability rather than specific performance requires the analysis of many distinct execution environments instead of details about a single environment. With the goal of providing more useful information for the analysis and optimization of code for parallel scalability, this work introduces the PaScal Viewer tool. It presents an novel and productive way to visualize scalability trends of parallel programs. It consists of four diagrams that offers visual support to identify parallel efficiency trends of the whole program, or parts of it, when running on scaling parallel environments with scaling problem sizes.

Yams (Dioscoreaspp.) are one of the main root and tuber crops in the world, especially within the species complexDioscorea cayenensis/D. rotundata. Few studies have been conducted in Brazil with these species, including genetic diversity. The objective of this study was to characterize the genetic diversity of local varieties ofD. cayenensisandD. rotundatausing morphological and molecular markers, and provide information on the management and use of the crop by family farmers from different regions in Brazil. Thus, yam tubers were sampled from several municipalities in the South, Southeast and Northeast regions. Eighteen morphological traits and ten microsatellite loci were used to analyse 47 yam accessions (23D. cayenensisand 24D. rotundata). Species identification was carried out after field morphological evaluation. Spatial genetic analysis indicated significant structure among the local varieties, mostly between regions and species. Both cluster and Bayesian analyses showed a separation of the accessions into two distinct groups: group I with accessions originated from the Southeast region and group II with accessions originated from the Northeast region, while accessions from the South region were intermediate or included in either group. The results showed a separation betweenD. cayenensisandD. rotundataaccessions in Brazil, and thatD. cayenensisoccurs predominantly in the Southeast region, whileD. rotundataoccurs in the Northeast region. Further studies with larger sampling would be welcome in order to confirm these findings. Also, this study highlights the importance of family farmers in the genetic diversity conservation of these species in Brazil.

The impact of the partonic structure on the description of the hadronic cross-sections is investigated considering a multichannel eikonal model based on the Good–Walker approach. The total, elastic and single diffractive cross-sections are estimated considering different parametrizations for the parton distribution functions and the predictions are compared with the experimental data for proton–proton [Formula: see text] and antiproton–proton [Formula: see text] collisions. We show that the description of the high-energy behavior of the hadronic cross-sections is sensitive to the partonic structure.

The study aimed to evaluate the antimicrobial activity, antioxidant, toxicity and phytochemical screening of the Red Propolis Alagoas. Antimicrobial activity was evaluated by disk diffusion method. Determination of antioxidant activity was performed using the DPPH assay (1.1-diphenyl-2-picrylhydrazyl), FTC (ferric thiocyanate) and determination of phenolic compounds by Follin method. Toxicity was performed by the method of Artemia salina and cytotoxicity by MTT method. The phytochemical screening for the detection of allelochemicals was performed. The ethanol extract of propolis of Alagoas showed significant results for antimicrobial activity, and inhibitory activity for Staphylococcus aureus and Candida krusei. The antioxidant activity of the FTC method was 80% to 108.3% hydrogen peroxide kidnapping, the DPPH method showed an EC50 3.97 mg/mL, the content of total phenolic compounds was determined by calibration curve gallic acid, resulting from 0.0005 mg/100 g of gallic acid equivalent. The extract was non-toxic by A. salina method. The propolis extract showed high activity with a higher percentage than 75% inhibition of tumor cells OVCAR-8, SF-295 and HCT116. Chemical constituents were observed as flavonones, xanthones, flavonols, and Chalcones Auronas, Catechins and leucoanthocyanidins. It is concluded that the extract can be tested is considered a potential source of bioactive metabolites. Resumo O trabalho teve como objetivo avaliar a atividade antimicrobiana, antioxidante, a toxicidade e a prospecção fitoquímica da Própolis Vermelha de Alagoas. A atividade antimicrobiana foi avaliada pelo método de difusão em disco. A determinação do potencial antioxidante foi realizada utilizando o método de DPPH (1,1-difenil-2-picrilhidrazil), FTC (Tiocianato Férrico) e determinação de compostos fenólicos pelo método de Follin. A toxicidade foi realizada pelo método de Artemia salina e a citotoxicidade pelo método do MTT. Foi realizada a prospecção fitoquímica para a pesquisa de aleloquímicos. O extrato etanólico da própolis vermelha de Alagoas apresentou resultados significantes para atividade antimicrobiana, tendo a atividade inibitória para Staphylococcus aureus e Candida krusei. Quanto a atividade antioxidante o método de FTC teve 80% a 108,3% de sequestro de peróxido de hidrogênio, o método de DPPH apresentou um CE50 de 3,97 μg/mL, o teor de compostos fenólicos totais foi determinado mediante curva de calibração do ácido gálico, tendo resultado de 0,0005 mg/100 g equivalente de ácido gálico. O extrato foi atóxico pelo método de A. salina. O extrato da própolis mostrou elevada atividade com percentual de inibição maior que 75% sobre células tumorais OVCAR-8, SF-295 e HCT116. Foram observados constituintes químicos como flavononas, xantonas, flavonóis, Chalconas e Auronas, Catequinas e Leucoantocianidinas. Conclui-se que o extrato testado pode ser considerado é uma fonte potencial de metabólitos bioativos.

Protected areas are often used by scientists to observe natural processes and organisms in habitats that have been minimally influenced by human actions. In contrast to many PA objectives, their effectiveness for promoting and supporting scientific research can be easily quantified in terms of quantity and quality of scientific products (primarily peer-reviewed articles) that are based on research within a PA’s boundaries. In addition to their contribution to global scientific knowledge, these research products may support local conservation efforts and contribute to park management, monitoring and governance. Here, we investigate the effectiveness of Neotropical PAs at supporting scientific research based on data from the World Database of Protected Areas (WDPA). Specifically, we randomly selected 102 PAs from each designation from the Latin American and Caribbean region, to give a total of 612 PAs. A total of 444 PAS did not return any results and only 30 were associated with more than 10 publications. Research topics varied widely in the PAs in our dedicated sample, but we found an evident trend to research related to geosciences and paleontology. Conservation and biodiversity were secondary subjects. there seems to be a lack of influence of PAs type and presence of management plan on scientific productivity. On the other hand, we have seen that most areas do not present a management plan, the absence of which makes it more difficult to assess the effectiveness of these areas.

Made available in DSpace on 2019-10-06T15:17:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-03-01 Nelore heifers usually begin their reproductive life at ≥24 months of age mainly due to suboptimal nutritional conditions and genetics. This study aimed to determine the effect of expected progeny difference (EPD) for age at first calving and average daily gain (ADG) on puberty in Nelore (Bos taurus indicus) heifers. A total of 58 weaned heifers (initial BW=174±6 kg; age=9±1 months) were allocated into 28 feedlot pens. Heifers were born from four sires, of which two had low EPD for age at first calving (L; n=33) and two had high EPD for age at first calving (H; n=25). Then, heifers of each EPD were randomly assigned to high ADG (HG; 0.7 kg) or low ADG (LG; 0.3 kg), resulting in four treatments: heifers from L sires were submitted to either HG (LHG; n=17) or LG (LLG; n=16), and heifers from H sires were submitted to either HG (HHG; n=12), or LG (HLG; n=13). The HG heifers were fed a 75% grain diet, whereas the LG heifers received 93% of forage in their diet. Blood samples were collected at 9, 14, 18, 24 and 28 months of age for IGF1 and leptin determination. There was a treatment effect (P

In the present investigation we study the leading and subleading high-energy behavior of hadron-hadron total cross sections using a best-fit analysis of hadronic scattering data. The parametrization used for the hadron-hadron total cross sections at high energy is inspired by recent results obtained by Giordano and Meggiolaro (2014) using a nonperturbative approach in the framework of QCD and it reads $\sigma_\text{tot} \sim B\ln^2 s + C\ln s\ln\ln s$. Both $B$ and $C$ are obtained by means of best-fits to data for proton-proton and antiproton-proton scattering, including recent data obtained at the LHC, and also to data for other meson-baryon and baryon-baryon scattering processes. The results are compared to the theoretical predictions existing in the literature. In particular, following the above-mentioned nonperturbative QCD approach, we also consider fits where the parameters $B$ and $C$ are set to $B = \kappa B_\text{th}$ and $C = \kappa C_\text{th}$, where $B_\text{th}$ and $C_\text{th}$ are universal quantities related to the QCD stable spectrum, while $\kappa$ (treated as an extra free parameter) is related to the asymptotic value of the ratio $\sigma_\text{el}/\sigma_\text{tot}$. Different possible scenarios are then considered and compared., Comment: 33 pages, 7 tables, 7 figures