University of São Paulo
  • São Paulo, Estado de Sao Paulo, Brazil
Recent publications
Resumo: Nesse trabalho foi realizada uma decomposição espacial do crescimento da Produtividade Total dos Fatores (PTF) do setor agropecuário brasileiro, incluindo componentes diretos (próprios) e indiretos (spillover), no contexto de uma análise de fronteira de produção espacial autorregressiva (SAR) para dados em painel, utilizando os dados censitários de 1995/96, 2006 e 2017 a partir de unidades produtivas referentes a 510 Regiões Geográficas Imediatas (RGI). Os resultados obtidos mostram que o crescimento da PTF foi de 3,87% a.a. na média do período completo, considerando-se apenas os efeitos diretos, e de 6,96% a.a., considerando-se os efeitos totais. Constatou-se também um maior crescimento da PTF no período mais recente e isso está relacionado à expansão da fronteira agrícola para as regiões com baixa produtividade anteriormente. Variáveis como financiamento da agricultura e pecuária, aptidão agrícola, malha rodoviária, plantio direto, correção de solo, escolaridade superior e assistência técnica, mostraram-se estatisticamente significativas na determinação da PTF. Os resultados sugerem que o crescimento da PTF é correlacionado espacialmente e temporalmente, e que spillovers espaciais e seus efeitos locais e globais impactaram a PTF nos três períodos censitários analisados.
We present various approaches to J. Herzog's theory of generalized local cohomology and explore its main aspects, e.g., (non-)vanishing results as well as a general local duality theorem which extends, to a much broader class of rings, previous results by Herzog-Zamani and Suzuki. As an application, we establish a prescribed upper bound for the projective dimension of a module satisfying suitable cohomological conditions, and we derive some freeness criteria and questions of Auslander-Reiten type. Along the way, we prove a new characterization of Cohen-Macaulay modules which truly relies on generalized local cohomology, and in addition we introduce and study a generalization of the notion of canonical module.
This paper aims to introduce the implementation parameters of the layered infill patterns in additive manufacturing to evaluate their effects on the actual density in the fabricated parts. To achieve this goal, parameters involved in shaping different infill patterns are presented and the significance of different input parameters on the output (actual) infill density is evaluated. The reference models for infill implementation are generic cubic and cylindrical models as their specific geometries lead to fewer geometric parameters affecting infill density error and provide informative case studies.
A pre-processing tool for fully-Lagrangian particle-based computational fluid dynamics methods is presented in this work. It adopts relatively simple strategies to generate particle models of the elements of the computational domain from boundaries represented by triangular meshes. Essentially, it is based on identification of the relative positions between cubic lattice nodes and the meshes to create particles that represent the geometry of the elements and assign the material type of the particles that are required for the simulations. Focusing on the recognition of the lattice nodes inside closed surfaces, variants of ray-casting and rasterization algorithms were proposed and evaluated. As a result, the rasterization considering three different orthogonal reference planes is the most accurate one with relatively low computational cost. Examples of the successful applications of the pre-processing tool are also provided.
Building Information Modelling is being adopted worldwide and universities are thus expected to provide the market with new professionals with BIM knowledge and skills. However, introduction of this theme into the curriculum can be challenging to teaching staff. Having successful implementation examples can help carrying on this task. This paper presents the structure, syllabus, adopted tools and activities of an introductory BIM course offered to first-year engineering students. Implemented with only 2 credits, it covers BIM fundamental concepts and develops collaboration skills and abilities with BIM software tools. It was effectively deployed on big classes and successfully offered both in face-to-face and remote modes, adopting a practice focus. An innovative organization for student group projects was adopted, enabling student participation on several projects, performing a different role in each one. Perceived benefits to students’ development are reported. The covid-19 pandemics impact is discussed. Future improvements in the course are suggested. Overall results achieved were considered very good.
Ramps are elements of vertical circulation adopted in modern architecture and that allow for the creation of a fluid and continuous spaces, both visually and formally. Among the design strategies employed by Vilanova Artigas, one that stands out is the adoption of ramps to bring these concepts into his projects. This text presents the results of the research that has analyzed the projects and works with ramps designed by Vilanova Artigas through the study of texts written by the architect, visits and photographs, investigative drawings, geometric and graphic analysis, physical and digital models, relating theory and design in the modern period of Brazilian São Paulo architecture. The research has found that the ramps are presented not only as vertical circulation elements but as a part of the architectural program, as an additional environment in Vilanova Artigas’ work that promotes and encourages meetings and coexistence, in addition to materializing concepts inherent to Modern Architecture. The geometry of the ramps in the residential work of Artigas materializes concepts of his architecture and follows in constructive harmony with the adoption of reinforced concrete.
Historically, architecture gradually became controlled by modulation, proportion, rhythm, harmony, and orthogonality of regular forms. In his investigation, Le Corbusier renews this fact maintaining the precise orthogonality of the right angle and modulation as a means to achieve his mathematical ‘vérités réconfortantes’. In recent years parametric modelling allows us to combine a great number of parameters, conducting us to explore and discover new possibilities to plan architectural forms. In this paper we study corbusian window panels using PM. The methodological procedures were: i) drawing of the grid of proportions; ii) parametric redrawing of the red and blue series; iii) geometric study of the so-called “jeu des panneaux”, with the reconstruction of the 2.26 m square and its golden section; iv) development of algorithms based on the values of the red and blue series; v) generation of combinations among parameters; vi) discussion of results and analysis. Using Grasshopper, the aim of this article is to report the parametric study of the red and blue series of the corbusian Modulor.
Computational models and statistics are becoming more important in professional sports, particularly in soccer. With the advance in the Computer Vision area, information such as pose recognition and player orientation are useful for several applications: team statistics, player tracking, etc. Analyzing the data achieved can improve team performance. This article presents a technique to determine the pose of every player on a soccer field throughout the match. Specific hand-held devices for soccer players can determine and track the position of the player only for their own team. However, it fails in determining the posture of the player. Conventional pose determination of the player does not work well when there is a large number of people in the image. This work overcomes such gaps by combining the person detector YOLO and the pose recognizer OpenPose. The proposed solution utilizes regular transmission recordings of previous matches. The developed approach can successfully determine the player’s posture through these videos. However, this is only the beginning of Computer Vision applied to sports. For future work, player orientation and automatic event detection and classification are expected to be developed.KeywordsSoccerPose recognitionImage processing
Engineering uses scientific knowledge to design or create and fabricate an object or a system. Contrary to that, reverse engineering starts from a product or process to know about or improve it. There are several reverse engineering techniques, however three of them are detailed and used in this work: 3D reconstruction from slice images, surface reconstruction from a point cloud, and component virtualization using images and measurements. The present work aims to create useful objects for shoulder surgical pre-planning, through the application of reverse engineering methods and the 3D printing technology. The 3D reconstruction from slice images is applied to reconstruct the scapula of as anonymous patient from computed tomography (CT), following the Digital Imaging and Communications in Medicine format (DICOM). The surface reconstruction from a point cloud is applied to recreate the curvature of the scapula’s glenoidal cavity using a Non-Uniform Rational Basis Spline (NURBS) surface. The 3D reconstruction from slice images is the source of the implant component representation, principal part of the arthroplasty implant. As contribution, the three objects described were digitally recreated and 3D printed with polylactic acid filament. The synthetic models served as the basis for research that will be published in other articles.
The objective of the paper is to share the experience on adoption of a Project-based Learning approach in the Engineering Design Graphics (EDG) course at the Escola Politécnica of the University of São Paulo. Flipped classroom reinforced by readiness assessments, and the intensive use of CAD systems for modeling, simulation and prototyping by laser cutting and 3D printing were also adopted. The background of the course reformulation, contents and activities are presented as well as discussions on the challenges and solutions implemented.
In the last decade, other quality attributes have emerged as the main aspects that impact pork consumers acceptance, such as environmentally friendly production, nutritional value, and animal welfare. This study applies a Check-All-That-Apply (CATA) questionnaire for sensory characterization of loins from genetically lean immunocastrated male pigs fed diets containing either a standard commercial diet with 1.5 % soybean oil (control) or 3 % oil from either soybean oil (SO), canola oil (CO), or fish oil (FO) during the growing-finishing phases. Twenty CATA attributes for loin samples were generated. We interviewed 101 consumers to select all the CATA terms that they considered suitable to characterize sensory attributes of longissimus lumborum muscle samples of pigs from each dietary treatment. The CATA results indicated differences among pork loin samples depending on the source and inclusion level of dietary oil. Loins from pigs fed 3 % SO were characterized by a higher frequency of the “juicy texture” attribute (p < 0.05) and a lower frequency of the “dry texture” attribute (p < 0.05) compared to loins from 3 % FO-fed pigs. Moreover, loins from pigs fed 3 % SO had a lower citation frequency of the “tasteless” attribute (p < 0.05) compared to loins from 3 % FO-fed pigs. The attributes “cooked pork meat-like taste”, “juicy texture”, “tender texture”, and “brightness” were placed close to the overall liking. “Tender texture”, “juicy texture”, “pork meat-like” (odor and taste), and “cooked pork meat-like taste” attributes were considered drivers of liking. Feeding genetically lean immunocastrated male pigs with diets containing 3 % SO may be advisable from a pork sensory quality perspective. CATA; dietary oil source; immunologic castration; sensory profile; pork meat
Non-invasive brain stimulation (NIBS) techniques have been increasingly used over the dorsolateral prefrontal cortex (DLPFC) to enhance working memory (WM) performance. Notwithstanding, NIBS protocols have shown either small or inconclusive cognitive effects on healthy and neuropsychiatric samples. Therefore, we assessed working memory performance and safety of transcranial direct current stimulation (tDCS), intermittent theta-burst stimulation (iTBS), and both therapies combined vs placebo over the neuronavigated left DLPFC of healthy participants. Twenty-four subjects were included to randomly undergo four sessions of NIBS, once a week: tDCS alone, iTBS alone, combined protocol and placebo. The 2-back task and an adverse effect scale were applied after each NIBS session. Results revealed a significantly faster response for iTBS (b= -21.49, p= 0.04), but not for tDCS and for the interaction tDCS vs. iTBS (b= 13.67, p= 0.26 and b= 40.5, p= 0.20, respectively). No changes were observed for accuracy and no serious adverse effects were found among protocols. Although tolerable, an absence of synergistic effects for the combined protocol was seen. Nonetheless, future trials accessing different outcomes for the combined protocols, as well as studies investigating iTBS over the left DLPFC for cognition and exploring sources of variability for tDCS are encouraged.
Zinc (Zn) is a micronutrient considered essential to plants which can be supplied through seed treatment. The treatment of soybean [Glycine max (L.) Merr.] seeds with Zn, however, is still not well known as regards the uptake and mobilization dynamics of the nutrient during the germination process. This study aimed to evaluate the uptake and distribution dynamics of Zn applied to soybean seeds at two levels of vigor during germination using X-ray micro-fluorescence spectroscopy (µ-XRF). Zinc treatments corresponded to 0, 2, 4 and 8 g of Zn per kg of seeds. High and low vigor seeds that had been treated were located appropriately so as to promote germination. Zn intensity measurements with µ-XRF were taken in different parts (“regions”) of the seeds (seed coat, cotyledon, and embryonic axis) after 8, 16 and 24 h of imbibition and seedlings (primary root, hypocotyl, plumule, cotyledon, and seed coat) after 48, 72 and 96 h of germination. High vigor seeds showed higher Zn intensity in the embryonic axis in the first 16 h, while low vigor seeds showed higher intensity after 24 h. After 48, 72 and 96 h of germination low vigor seedlings showed higher Zn intensity than high vigor seedlings in the primary root. It was concluded that µ-XRF is an efficient technique for identifying variances in the dynamics of Zn uptake and mobilization during the germination of soybean seeds with different vigor levels. Glycine max (L.) Merr; µ-XRF; seed coating; seed physiology; seed vigor
This work evaluates the potential root causes of fatigue and its relationships with accident risks using a bio-mathematical model approach and a robust sample (N = 8476) of aircrew rosters from the Brazilian regular aviation, extracted from the Fadigômetro database. The fatigue outcomes derive from the software Sleep, Activity, Fatigue, and Task Effectiveness Fatigue Avoidance Scheduling Tool (SAFTE-FAST), which considers the homeostatic process, circadian rhythms and the sleep inertia. The analyses include data from January 2019 until March 2020 and show relevant group effects comparing early 2019 and 2020, with the latter presenting lower fatigue outcomes in most cases. The average minimum SAFTE-FAST effectiveness during critical phases of flight (departures and arrivals) decreases cubically with the number of shifts that elapse totally or partially between mid-night and 6 a.m. within a 30-day period (NNS). As a consequence, the relative fatigue risk increases by 23.3% (95% CI, 20.4–26.2%) when increasing NNS from 1 to 13. The average maximum equivalent wakefulness in critical phases also increases cubically with the number of night shifts and exceeds 24 h for rosters with NNS above 10. The average fatigue hazard area in critical phases of flight varies quadratically with the number of departures and arrivals within 2 and 6 a.m. (NWocl). These findings demonstrate that both NNS and NWocl represent potential root causes of fatigue and therefore should be considered key performance indicators and kept as low as reasonably practical when building aircrew rosters, in order to properly manage the fatigue risk. The effectiveness scores obtained at 30-minute time intervals allowed a model estimate for the relative fatigue risk as a function of the time of the day, whose averaged values show reasonable qualitative agreement with previous measurements of pilot errors in the cockpit. Moreover, the 2019 data revealed a risk exposure factor two times (14%) higher than the figures reported by de Mello et al. (2008) (7%), within 0h00 do 05h59. Tailored analyses of the SAFTE-FAST inputs for afternoon naps before night shifts, commuting from home to station and vice-versa, and bedtime before early-start shifts were carried out using the responses of a questionnaire. The average fatigue hazard area in critical phases of flight increases by 43 to 63% switching off the afternoon naps, 14 to 21% increasing the commuting from one to two hours and 35 to 54% switching off the advanced bedtime criterion, with significant group effects in all cases (p<0.001), evidencing the need of a better and more accurate understanding of these parameters when modelling fatigue risk factors. The non-linear relationships between SAFTE-FAST outcomes and key roster’s parameters, such as NNS and NWocl, provided a novel statistical approach for risk assessment and led to few safety recommendations to the aviation sector regarding regulatory reviews and fatigue risk management and mitigation policies.
The use of pre-hydrated cement in formulation of mortar and concrete is common because there is not always effective control on the cement production, grinding, transportation and subsequent storage. This paper presents a case study on the optimization of admixture for use with prehydrated cement by assessing changes in the rheological properties of Portland cement artificially pre-hydrated. The cement was artificially pre-hydrated by exposure to relative humidity (RHs) of 90%, in an environment of NH4Cl saturated solution. Additionally, the cement pastes were evaluated with and without superplasticizer. Stepped flow test using a parallel-plate geometry was the method choose to evaluate the rheological behavior, apparent viscosity, yield stress and hysteresis area of each paste at the early age. Oscillatory rheometry was conducted to evaluate the storage modulus (G’), comparing the consolidation with the hydration kinetics obtained by calorimetric evaluation of the same suspensions. Initial rheometer results indicate that the pre-hydrated sample presents lower level of shear stress than the reference sample, because of the higher reactivity of the non-pre-hydrated sample.
Background/objective Chronic pain due to osteoarthritis (OA) is a prevalent cause of global disability. New biomarkers are needed to improve treatment allocation, and genetic polymorphisms are promising candidates. Method We aimed to assess the association of OPRM1 (A118G and C17T) and brain-derived neurotrophic factor (BDNF [G196A]) polymorphisms with pain-related outcomes and motor cortex excitability metrics (measured by transcranial magnetic stimulation) in 113 knee OA patients with chronic pain. We performed adjusted multivariate regression analyses to compare carriers versus non-carriers in terms of clinical and neurophysiological characteristics at baseline, and treatment response (pain reduction and increased cortical inhibitory tonus) after rehabilitation. Results Compared to non-carriers, participants with polymorphisms on both OPRM1 (A118G) and BDNF (G196A) genes were less likely to improve pain after rehabilitation (85 and 72% fewer odds of improvement, respectively). Likewise, both carriers of OPRM1 polymorphisms (A118G and C17T) were also less likely to improve cortical inhibition (short intracortical inhibition [SICI], and intracortical facilitation [ICF], respectively). While pain and cortical inhibition improvement did not correlate in the total sample, the presence of OPRM1 (A118G) and BDNF (G196A) polymorphisms moderated this relationship. Conclusions These results underscore the promising role of combining genetic and neurophysiological markers to endotype the treatment response in this population.
The objectives of this research were to assess the genetic diversity, population structure, linkage disequilibrium and perform a genome-wide association study (GWAS) to search for single nucleotide polymorphisms (SNPs) that associate with the resistance of Pacific white shrimp (Litopenaeus vannamei) to White Spot Syndrome Virus (WSSV). The line here analyzed was formerly founded with animals originated from different origins (Ecuador, Panama, and United States of America), with a history of resistance to WSSV and they have undergone a selection process, currently reaching up to F6 generation. In a controlled challenge to WSSV, this line showed a binary survival (39.0% ± 1.1%) and time to death (109.7 ± 0.9 h post-infection) (n = 1944). The population was genotyped using a commercially available 50 K SNP chip and ∼32 K SNPs remained after quality control of genotypes. Population structure, extent and decay of linkage disequilibrium (LD), and genetic variability in the population were evaluated. The principal component analysis (PCA) did not show apparent genetic stratification in the population. The LD decay estimated, revealed a rapid decrease in r² as the physical distance between markers increased. The most significant decrease was observed in the first 30Kb of distance, suggesting the need to use a higher density of informative markers to meet the requirement of a genome-wide association study in L. vannamei. The observed and expected heterozygosities were both = 0.38, which indicates that the population presents acceptable genetic variability for WSSV resistance. Two SNPs were significantly associated to WSSV resistance at a genome-wide level, which in turn together explained 0.17% of the genetic variance for the trait. One identified SNP surpassing the genome-wide significance threshold (chromosome 1 at 51207389 bp) is located near potential candidate genes, such as Arylsulfatase B-like (ARSB), and D-beta-hydroxybutyrate dehydrogenase mitochondrial-like (βhyD); which was linked to the humoral immune response to WSSV, in addition to the Putative mediator of RNA polymerase II transcription subunit 26 (PMed26); which are associated with the hepatopancreas immune response against infection of WSSV and acute hepatopancreatic necrosis disease (AHPND). Our results indicate a polygenic architecture for WSSV resistance in L. vannamei, suggesting that incorporating genome-wide SNP information, through genomic selection, might be the most appropriate approach to accelerate the genetic progress for this trait.
The Dark Triad (DT) is comprised of a set of personality traits—Machiavellianism, psychopathy and narcissism—related to low agreeableness and antisocial behavior. While emerging evidence links these traits to COVID-19 related behaviors, limited research has sought to identify the beliefs and attitudes that translate the former into the latter. To address this gap in the literature, Nowak et al. (2020) recently surveyed a polish Western sample (n = 755), finding initial evidence that health beliefs help explain the connection between Dark Triad traits and COVID-19 related preventive and hoarding behaviors. Our objective in the present study was to examine whether the findings reported by Nowak et al. could be replicated using data from a non-WEIRD population. Using structural equation modeling and data from a Brazilian sample (N = 406), we replicated most of Nowak et al.'s (2020) findings.
The study of shear failure in concrete beams is one of the subjects growing in importance due to both the recent reformulations, and increasingly higher cross-section depths used. For instance, the recent updates in the ACI 318 (2019) shows the need to incorporate the size effect in the design of reinforced concrete elements. In this study, the same database adopted by the ACI-ASCE Committee DAfStb 445-D has been used to calculate shear strength, with and without the consideration of size effect, i.e., the design prescribed by ACI 318 (2014), ACI 318 (2019), Frosch et al. (2017), and the ABNT NBR 6118 (2014). Later these predictions are compared with test results. A dispersion analysis has outlined the trends regarding compressive strength, span to depth ratio, longitudinal reinforcement ratio and beam depth. Every variable was discussed per interval, delineating the causes related to the observable trends. Regarding the most prominent influences (effective depth and longitudinal reinforcement ratio), the approaches considering them directly through factors had provided results with no appreciable trends, with lower coefficients of variation (COV) and substantially more conservative for higher cross-section depths. As the Brazilian code does not consider both, a correction factors, determined by a two-step regression analysis on these parameters to adjust this design, are briefly introduced.
Nowadays, structural “limit state” design is made using characteristic or nominal values of actions, partial safety factors and load combination factors. The actual loading that a structure will be subjected to throughout its life is not known at the design phase. Yet, probabilistic models of such loadings are useful for the rational determination of partial safety factors and load combination factors. The probabilistic model leading to nominal live loads of NBR 6120:2019 (Design Loads for Structures) has never been openly discussed. Herein a simple probabilistic model describing spatial and temporal variabilities of live loads in buildings is presented and discussed. The model is built as a sum of two stochastic processes representing the sustained and intermittent parts of the live load. Model parameters are the ones recommended by the Joint Committee on Structural Safety (JCSS), based on extensive surveys done in several countries. By way of Monte Carlo simulations, sample values of live load actions are obtained for buildings of different occupancy types. These values are compared with those recommended by international standards, and those recommended in NBR 6120:2019 and NBR 8681:2003 (Actions and Safety of Structures). The corresponding statistics for the fifty-year extreme and arbitrary point-in-time distributions of live loads are presented; these statistics are very relevant for reliability analyses and for reliability-based code calibration. The stochastic live load model is also employed in a reliability-based calibration to obtain partial safety factors and load combination factors to be used in Brazilian design codes, for ultimate and serviceability limit state verifications.
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Daniel Cordeiro
  • School of Arts, Sciences and Humanities
Charles Lourenco
  • Departamento de Neurociências e Ciências do Comportamento (Ribeirão Preto)
Rua da Reitoria, 374, 05508-010, São Paulo, Estado de Sao Paulo, Brazil
Head of institution
Reitoria da Universidade de São Paulo