540 research outputs found
A computational approach to forecasting and minimizing electricity costs in the short-term market for distributors in Brazil
In Brazil, the electric power distributors must buy electricity on auctions one, three and five years ahead. If there is inefficiency in the contracting of electric energy, the chamber of Commercialization of Electric Energy, which enables the commercialization, can apply penalties. Thus, this paper proposes a computational approach to forecasting electricity by the class of the consumer using a multi-layer perceptron artificial neural network with a backpropagation algorithm and a prediction using time series techniques through the Bayesian and Akaike selection criteria. The forecast of electricity consumption can serve as support in the purchase of electricity in auctions in the regulated contracting environment and in the process of settlement of differences and for energy management, customer service, and distributor billing. The results show that a multilayer network with a backpropagation algorithm is able to learn the behavior of the data that influences the electric energy consumed by consumption class and can be used to follow the evolution in the demand of each class of consumption and, consequently, to help distributors in the process of contracting of electricity, reduce losses like fines, and reduce the costs of the energy distributor
On the superposition of mean advective and eddy-induced transports in global ocean heat and salt budgets
Ocean thermal expansion is a large contributor to observed sea level rise, which is expected to continue into the future. However, large uncertainties exist in sea level projections among climate models, partially due to intermodel differences in ocean heat uptake and redistribution of buoyancy. Here, the mechanisms of vertical ocean heat and salt transport are investigated in quasi-steady-state model simulations using the Australian Community Climate and Earth-System Simulator Ocean Model (ACCESS-OM2). New insights into the net effect of key physical processes are gained within the superresidual transport (SRT) framework. In this framework, vertical tracer transport is dominated by downward fluxes associated with the large-scale ocean circulation and upward fluxes induced by mesoscale eddies, with two distinct physical regimes. In the upper ocean, where high-latitude water masses are formed by mixed layer processes, through cooling or salinification, the SRT counteracts those processes by transporting heat and salt downward. In contrast, in the ocean interior, the SRT opposes dianeutral diffusion via upward fluxes of heat and salt, with about 60% of the vertical heat transport occurring in the Southern Ocean. Overall, the SRT is largely responsible for removing newly formed water masses from the mixed layer into the ocean interior, where they are eroded by dianeutral diffusion. Unlike the classical advective–diffusive balance, dianeutral diffusion is bottom intensified above rough bottom topography, allowing an overturning cell to develop in alignment with recent theories. Implications are discussed for understanding the role of vertical tracer transport on the simulation of ocean climate and sea level
Intersetorialidade e potenciais conflitos de interesse entre governos e setor privado comercial no âmbito das ações de alimentação e nutrição para o enfrentamento de doenças crônicas não transmissíveis
This article analyzed the potential conflicts of interest between government and private commercial sectors in the area of food and nutrition (FN) activities within the context of intersectoral proposals for dealing with chronic non-communicable diseases (CNCD) in Brazil. To this end, academic articles and institutional documents published after 2000 were identified that addressed FN actions in CNCD policies guided by intersectoriality. Elements that contributed to understanding the potential conflicts of interest between governments and the private, commercial sector within the context of intersectoral strategies to deal with CNCD were prioritized. It was concluded that the principle of intersectoriality disassociated from a political process that complicates the eligibility criteria and institutional practices of the sectors responsible for the set of actions that comprise government policies may serve as facilitators for favoring commercial interests. Participation in the decision-making process of the sectors of commercial interest whose practices, driven by increased demand for their products and the progressive concentration of power, contradict the purposes and principles of public policy, may delay, reduce, or prevent effective actions to reduce CNCD. This possibility is particularly relevant in the context of attributions that are specific to government entities, especially regulatory strategies.Neste artigo foram analisados os potenciais conflitos entre interesses governamentais e privados de caráter comercial em torno das ações de alimentação e nutrição (AN) no âmbito de propostas intersetoriais de enfrentamento das DCNT no Brasil. Para tal, foram identificados artigos acadêmicos e documentos institucionais publicados a partir de 2000 que abordassem as ações de AN em políticas de DCNT pautadas pela intersetorialidade. Foram priorizados elementos que contribuíssem para a compreensão dos potenciais conflitos de interesse entre governos e o setor privado comercial no âmbito de estratégias intersetoriais de enfrentamento de DCNT. Concluiu-se que o princípio da intersetorialidade, desassociado de um processo político que problematize os critérios de eleição e as práticas institucionais dos setores que respondem pelo conjunto de ações que compõe as políticas governamentais, pode servir como facilitador do favorecimento de interesses comerciais. A participação no processo decisório de setores de interesse comercial cujas práticas ferem objetivos e princípios das políticas públicas, movidos pela expansão da demanda por seus produtos e pela concentração progressiva de poder, pode retardar, atenuar ou impedir ações efetivas na redução de DCNT. Esta possibilidade é particularmente relevante no âmbito de atribuições que são próprias aos entes Estatais, especialmente as estratégias regulatórias
AcMus: an open, integrated platform for room acoustics research
This article describes the design, implementation, and experiences with AcMus, an open and integrated software platform for room acoustics research, which comprises tools for measurement, analysis, and simulation of rooms for music listening and production. Through use of affordable hardware, such as laptops, consumer audio interfaces and microphones, the software allows evaluation of relevant acoustical parameters with stable and consistent results, thus providing valuable information in the diagnosis of acoustical problems, as well as the possibility of simulating modifications in the room through analytical models. The system is open-source and based on a flexible and extensible Java plug-in framework, allowing for cross-platform portability, accessibility and experimentation, thus fostering collaboration of users, developers and researchers in the field of room acoustics.CNPqFAPES
Blind competition on the numerical simulation of continuous shallow steel‐fiber reinforced concrete beams failing in bending
This article describes the second blind simulation competition (BSC) organized
by the fib WG 2.4.1, which aims to assess the predictive performance of models
based on the finite element method (FEM) for the analysis and design of fiber
reinforced concrete (FRC) structures. Slabs supported on columns or piles have
becoming competitive applications for FRC due to the technical and economic
benefits may be obtained by combining properly the fiber reinforcement mechanisms to those provided by conventional reinforcement placed, as a strip, in
the alignment of columns/piles. Therefore, a representative zone of this structural system, namely a hybrid fiber reinforced concrete (R/FRC) shallow beam,
is chosen in this BSC to show the potentialities of FRC in these types of applications, as well as to assess the predictive performance of FEM-based computational models on the design verification at serviceability and at ultimate limit
state conditions (SLS and ULS, respectively). Two statically indeterminateshallow beams of two equal spans were tested up to their failure, by recording
the applied loads, the strains in the conventional reinforcements and in the
FRC of the critical zones of the structure. By using digital image correlation,
the average crack width at the level of the flexural reinforcements was
recorded. The participants had to predict these results by receiving information
about the mechanical properties of the materials, the geometry of the prototypes and their loading and support conditions. In this article, the rules and
the results of this 2nd BSC competition are presented, and the data obtained
experimentally is thoroughly analyzed.PID2021-125553NB-I00; PTDC/ECI-EST/6300/202
XIPE: the X-ray Imaging Polarimetry Explorer
X-ray polarimetry, sometimes alone, and sometimes coupled to spectral and
temporal variability measurements and to imaging, allows a wealth of physical
phenomena in astrophysics to be studied. X-ray polarimetry investigates the
acceleration process, for example, including those typical of magnetic
reconnection in solar flares, but also emission in the strong magnetic fields
of neutron stars and white dwarfs. It detects scattering in asymmetric
structures such as accretion disks and columns, and in the so-called molecular
torus and ionization cones. In addition, it allows fundamental physics in
regimes of gravity and of magnetic field intensity not accessible to
experiments on the Earth to be probed. Finally, models that describe
fundamental interactions (e.g. quantum gravity and the extension of the
Standard Model) can be tested. We describe in this paper the X-ray Imaging
Polarimetry Explorer (XIPE), proposed in June 2012 to the first ESA call for a
small mission with a launch in 2017 but not selected. XIPE is composed of two
out of the three existing JET-X telescopes with two Gas Pixel Detectors (GPD)
filled with a He-DME mixture at their focus and two additional GPDs filled with
pressurized Ar-DME facing the sun. The Minimum Detectable Polarization is 14 %
at 1 mCrab in 10E5 s (2-10 keV) and 0.6 % for an X10 class flare. The Half
Energy Width, measured at PANTER X-ray test facility (MPE, Germany) with JET-X
optics is 24 arcsec. XIPE takes advantage of a low-earth equatorial orbit with
Malindi as down-link station and of a Mission Operation Center (MOC) at INPE
(Brazil).Comment: 49 pages, 14 figures, 6 tables. Paper published in Experimental
Astronomy http://link.springer.com/journal/1068
Evaluation of Bacteria and Fungi DNA Abundance in Human Tissues
Whereas targeted and shotgun sequencing approaches are both powerful in allowing the study of tissue-associated microbiota, the human: microorganism abundance ratios in tissues of interest will ultimately determine the most suitable sequencing approach. In addition, it is possible that the knowledge of the relative abundance of bacteria and fungi during a treatment course or in pathological conditions can be relevant in many medical conditions. Here, we present a qPCR-targeted approach to determine the absolute and relative amounts of bacteria and fungi and demonstrate their relative DNA abundance in nine different human tissue types for a total of 87 samples. In these tissues, fungi genomes are more abundant in stool and skin samples but have much lower levels in other tissues. Bacteria genomes prevail in stool, skin, oral swabs, saliva, and gastric fluids. These findings were confirmed by shotgun sequencing for stool and gastric fluids. This approach may contribute to a more comprehensive view of the human microbiota in targeted studies for assessing the abundance levels of microorganisms during disease treatment/progression and to indicate the most informative methods for studying microbial composition (shotgun versus targeted sequencing) for various samples types
Imprinted antibody responses against SARS-CoV-2 Omicron sublineages
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sublineages carry distinct spike mutations resulting in escape from antibodies induced by previous infection or vaccination. We show that hybrid immunity or vaccine boosters elicit plasma-neutralizing antibodies against Omicron BA.1, BA.2, BA.2.12.1, and BA.4/5, and that breakthrough infections, but not vaccination alone, induce neutralizing antibodies in the nasal mucosa. Consistent with immunological imprinting, most antibodies derived from memory B cells or plasma cells of Omicron breakthrough cases cross-react with the Wuhan-Hu-1, BA.1, BA.2, and BA.4/5 receptor-binding domains, whereas Omicron primary infections elicit B cells of narrow specificity up to 6 months after infection. Although most clinical antibodies have reduced neutralization of Omicron, we identified an ultrapotent pan-variant–neutralizing antibody that is a strong candidate for clinical development
Imprinted antibody responses against SARS-CoV-2 Omicron sublineages
SARS-CoV-2 Omicron sublineages carry distinct spike mutations and represent an antigenic shift resulting in escape from antibodies induced by previous infection or vaccination. We show that hybrid immunity or vaccine boosters result in potent plasma neutralizing activity against Omicron BA.1 and BA.2 and that breakthrough infections, but not vaccination-only, induce neutralizing activity in the nasal mucosa. Consistent with immunological imprinting, most antibodies derived from memory B cells or plasma cells of Omicron breakthrough cases cross-react with the Wuhan-Hu-1, BA.1 and BA.2 receptor-binding domains whereas Omicron primary infections elicit B cells of narrow specificity. While most clinical antibodies have reduced neutralization of Omicron, we identified an ultrapotent pan-variant antibody, that is unaffected by any Omicron lineage spike mutations and is a strong candidate for clinical development
Cultivation-Independent Methods Reveal Differences among Bacterial Gut Microbiota in Triatomine Vectors of Chagas Disease
Chagas disease is one of the most important endemic diseases of South and Central America. Its causative agent is the protozoan Trypanosoma cruzi, which is transmitted to humans by blood-feeding insects known as triatomine bugs. These vectors mainly belong to Rhodnius, Triatoma and Panstrongylus genera of Reduviidae. The bacterial communities in the guts of these vectors may have important effects on the biology of T. cruzi. For this reason, we analyzed the bacterial diversity hosted in the gut of different species of triatomines using cultivation-independent methods. Among Rhodnius sp., we observed similar bacterial communities from specimens obtained from insectaries or sylvatic conditions. Endosymbionts of the Arsenophonus genus were preferentially associated with insects of the Panstrongylus and Triatoma genera, whereas the bacterial genus Serratia and Candidatus Rohrkolberia were typical of Rhodnius and Dipetalogaster, respectively. The diversity of the microbiota tended to be the largest in the Triatoma genus, with species of both Arsenophonus and Serratia being detected in T. infestans
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