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Resumen Objetivo: Establecer el valor pronóstico del TRNSC basado en la necesidad de marcapasos en pacientes diagnosticados con aleteo atrial, pos-ablación. Métodos: Este cohorte prospectivo, realizado en el Instituto Nacional de Cardiología "Ignacio Chávez" en la Ciudad de México, evaluó pacientes sometidos a ablación para corregir el aleteo atrial; se midió el TRNSC post bloqueo autonómico. Resultados: La muestra de 40 pacientes se subdividió en 2 grupos según su requerimiento de marcapasos posterior a la ablación (P y NP). Se diagnosticó disfunción del nodo sinusal en 13 participantes (32.5%), de los cuales 10 (71.43%) requirieron marcapasos en comparación a 4 (28.57%) con función normal. En el grupo P la pausa del nodo sinusal post-ablación tuvo una media de 1.86 ± 0.96 s versus el grupo NP con 1.196 ± 0.52 s. En relación con el TRNSC, el grupo NP tuvo una media de 383.54 ± 67.96 ms vs. 1972.57 ± 3423.56 ms en el grupo P. 10 pacientes (25%) obtuvieron un TRNSC > 500 ms, de los cuales 100% requirieron marcapasos; de los 14 pacientes que requirieron marcapasos 10 (71.43%) tenían un TRNSC elevado (p ≤ 0.01). Conclusiones: El TRNSC tiene el potencial de ser una herramienta de pronóstico cuantitativo para la necesidad de futuros implantes de marcapasos en pacientes con disfunción del nodo sinusal, resultado de aleteo atrial pos-ablación. Esto podría ayudar a diagnosticar más temprano una disfunción del nodo sinusal, resultando en la reducción de la pérdida a largo plazo de la función cardíaca como efecto de la remodelación.

Abstract Objective: The objective of the study was to establish the prognostic value of CSNRT regarding the necessity for pacemaker implantation in patients with atrial flutter (AFL) post-ablation. Methods: This prospective cohort study, conducted at the National Institute of Cardiology "Ignacio Chavez" in Mexico City, assessed patients who had undergone ablation procedures to correct AFL, posterior to which an autonomic blockade was performed, and CSNRT was measured. Results: The sample for this investigation was 40 patients. These were subdivided into two study groups depending on their requirement of pacemaker implant post-ablation (Pacemaker P, No Pacemaker NP). Sinus node (SN) dysfunction was diagnosed in 13 (32.5%) of the 40 participants, 10 (71.43%) of which required a pacemaker implant, while only 4 participants (28.57%) with normal SN function required pacemakers. Ten out of the 14 patients (71.43%) who required a pacemaker had an elevated CSNRT > 500 ms (p ≤ 0.01). Post-ablation CSNRT mean was 383.54 ms ± 67.96 ms in the NP group versus 1972.57 ms ± 3423.56 ms in the P group. Furthermore, SN pause in the P group had a mean of 1.86 s ± 0.96 s versus the NP group with 1.196 s ± 0.52 s. Conclusion: CSNRT has the potential to be a quantitative prognostic tool for the assessment of future pacemaker implants in patients with AFL post-ablation. This could aid in the timely diagnosis of sinus node dysfunction, which could, in the long run, result in the reduction of cardiac functional capacity loss due to cardiac remodeling.

https://doi.org/10.24875/acm.22000031

Morphometry and yield of ‘Gigante’ forage cactus pear under irrigation and different planting densities
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Fonseca, Varley A.

; Donato, Sérgio L. R.

; Santos, Marcelo R. dos

; Silva, João A. da

; Oliveira, Carlos M.

; Batista, Renato da S.

Revista Caatinga

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Set 2023, Volume 36 Nº 3 Páginas 690 - 701

Resumo: En Pt | Texto: En Pt | PDF: En | PDF: Pt

ABSTRACT Growing forage cactus pear in semi-arid regions is an alternative when facing current climate changes, and improving its cropping systems is critical to increasing its yields. The objective was to evaluate morphometric characteristics and yield of ‘Gigante’ cactus pear under complementary irrigation with saline water and different planting densities. The research was carried out in the semiarid region of Bahia during the period from September 2017 to October 2019. A randomized block design was used with treatments arranged in split-split plots. Two irrigation intervals (7 and 14 days) were assigned to plots, four planting densities (20,000; 40,000; 60,000 and 80,000 plants per hectare) to subplots, and four irrigation levels (0, 11, 22 and 33% of ETo) to sub-subplots. High-salinity water (2.91 dS m-1), classified as C4S1, did not limit the growth and yield of ‘Gigante’ forage cactus pear for two crop cycles. Fresh matter and dry matter yields, fresh matter-based water use efficiency and dry matter-based water use efficiency were highest at planting densities of 61,465 and 67,786 plants ha-1, and 61,848 and 69,707 plants ha-1, respectively. The use of 33% ETo irrigation level increased morphometric characteristics, fresh matter yield in the first and second cycles, and dry matter yield in the first cycle. Applying increasing irrigation levels promotes reductions in fresh matterand dry matter-based water use efficiency.

RESUMO O cultivo de palma forrageira no semiárido é uma opção consciente frente às mudanças climáticas atuais, e a melhoria do seu sistema produtivo é fundamental para aumentar seu rendimento. Objetivou-se avaliar as características morfométricas e de rendimento de palma forrageira ‘Gigante’ sob irrigação complementar com água salina e diferentes densidades de plantio. A pesquisa foi realizada no semiárido baiano durante o período de setembro de 2017 a outubro de 2019. O delineamento experimental foi em blocos casualizados com parcelas subsubdivididas, sendo alocados nas parcelas dois turnos de rega (7 e 14 dias), nas subparcelas quatro densidades de plantio (20.000; 40.000; 60.000 e 80.000 plantas ha-1) e nas subsubparcelas quatro lâminas de irrigação (0, 11, 22 e 33% da ETo). A alta salinidade da água de irrigação (2,91 dS m-1), classificada como C4S1, não limitou o crescimento e a produtividade de palma forrageira ‘Gigante’, até o segundo ciclo de produção. As máximas produtividades de matéria verde e seca e de eficiência de uso da água com base nestas produtividades são obtidas com densidades de plantio de 61.465 e 67.786 plantas ha-1, e 61.848 e 69.707 plantas ha-1, respectivamente. A aplicação da lâmina com 33% da ETo promoveu incremento nas características morfométricas, aumento da produtividade de matéria verde no primeiro e segundo ciclo e da produtividade de matéria seca no primeiro ciclo. A aplicação de lâminas crescentes de irrigação promove redução da eficiência de uso da água com base nas produtividades de matéria verde e de matéria seca.

https://doi.org/10.1590/1983-21252023v36n321rc

Sweet potato yield and quality as a function of phosphorus fertilization in different soils
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Cordeiro, Carlos F. dos S.

; Echer, Fábio R.

; Batista, Guilherme D.

; Fernandes, Adalton M.

Revista Brasileira de Engenharia Agrícola e Ambiental

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Jun 2023, Volume 27 Nº 6 Páginas 487 - 495

Resumo: En Pt | Texto: En Pt | PDF: En | PDF: Pt

ABSTRACT Phosphorus (P) is an essential nutrient for growth and yield of sweet potatoes; in sandy soils, sweet potato yield and quality may be limited by application of low P doses, mainly in degraded areas. The objective of this work was to evaluate the effect of P doses on yield and quality of sweet potato root tubers grown in tropical sandy soils with different initial P availabilities: 23.2 mg dm-3 (high P - crop rotation) and 3.7 mg dm-3 (low P - post degraded pasture). Two experiments were carried out in a randomized block design, with four replicates. The treatments consisted of P doses (0, 22, 44, 88, and 176 kg ha-1) applied to the planting bed. Tuber yield, number and mean weight of tubers, P concentration in leaves and tubers, exported P, as well as the percentage of starch, reducing sugars, total sugars, and sucrose in the tubers were evaluated. P concentration in the soil was evaluated at the end of the experiment. In the area with high P availability (> 20 mg dm-3 - resin), increasing P doses did not increase root tuber yield and decreased root starch concentrations. In the area with low P availability (< 3.7 mg dm-3 - resin), root tuber yield and starch concentration peaked when applying 68 and 33 kg ha-1 of P, respectively. In areas after degraded pasture, with low initial soil P concentration, P fertilization for sweet potato crops should be carried out with a P dose of 68 kg ha-1. In areas with crop rotation and adequate soil P concentration, P fertilization should be carried out to replace the amount of P exported by the harvested root tubers to avoid decreases in soil fertility.

RESUMO O fósforo (P) é um nutriente essencial para o crescimento e produtividade da batata-doce, e em solos arenosos, a produtividade e a qualidade da batata-doce podem ser limitadas pela baixa dose de P aplicada, principalmente em áreas degradadas. O objetivo deste trabalho foi avaliar o efeito de doses de fósforo na produtividade e qualidade das raízes tuberosas de batata-doce cultivadas em solos arenosos tropicais com diferentes disponibilidades iniciais de P; 23,2 mg dm-3 (P alto - rotação de culturas) e 3,7 mg dm-3 (P baixo - pós pastagem degradada). Dois experimentos foram conduzidos em blocos casualizados, com quatro repetições. Os tratamentos consistiram de doses de P (0, 22, 44, 88 e 176 kg ha-1) aplicadas no sulco de plantio. Foram avaliadas a produtividade, número e peso médio de tubérculos, teor de P nas folhas e nos tubérculos, exportação de P, além da porcentagem de amido, açúcar redutor, açúcar total e sacarose nos tubérculos. No final do estudo foi avaliado o teor de P no solo. Em área com alta disponibilidade de P (> 20 mg dm-3 - resina), o aumento das doses de P não aumenta a produtividade de tubérculos e diminui as concentrações de amido nas raízes. Em área com baixa disponibilidade de P (< 3,7 mg dm-3 - resina), a produtividade de tubérculos e a concentração de amido atingiram o máximo ao aplicar 68 e 33 kg ha-1 de P, respectivamente. Cultivo de batata-doce em área após pastagem degradada com baixo teor inicial de P no solo, a adubação fosfatada deve ser realizada na dose de 68 kg ha-1 de P. Em área com rotação de culturas e teor adequado de P no solo, a adubação fosfatada deve ser realizada para repor a quantidade de P exportada pelas raízes tuberosas colhidas para evitar a perda da fertilidade do solo.

https://doi.org/10.1590/1807-1929/agriambi.v27n6p487-495

Sintomas Cardiopulmonares Pós-COVID-19: Preditores e Características de Imagem de Pacientes após a Alta Hospitalar
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Roberto, Kalil-Filho

; Saretta, Roberta

; Franci, André

; Baracioli, Luciano M.

; Galas, Filomena R. B. G.

; Gil, Juliana S.

; Ferino, Amanda

; Giacovone, Camilla

; Oliveira, Isabella

; Souza, Johnatan

; Batista, Vanessa

; Scalabrini Neto, Augusto

; Costa, Livia do Valle

; Ruiz, Amanda Danieleto

; Ledo, Carla B.

; Nascimento, Teresa Cristina D. C.

; Drager, Luciano F.

Arquivos Brasileiros de Cardiologia

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2023, Volume 120 Nº 5 elocation e20220642

Resumo: En Pt | Texto: En Pt | PDF: En | PDF: Pt

Abstract Background Most of the evidence about the impact of the post-acute COVID-19 Syndrome (PACS) reports individual symptoms without correlations with related imaging. Objectives To evaluate cardiopulmonary symptoms, their predictors and related images in COVID-19 patients discharged from hospital. Methods Consecutive patients who survived COVID-19 were contacted 90 days after discharge. The Clinic Outcome Team structured a questionnaire evaluating symptoms and clinical status (blinded for hospitalization data). A multivariate analysis was performed to address the course of COVID-19, comorbidities, anxiety, depression, and post-traumatic stress during hospitalization, and cardiac rehabilitation after discharge. The significance level was set at 5%. Results A total of 480 discharged patients with COVID-19 (age: 59±14 years, 67.5% males) were included; 22.3% required mechanical ventilation. The prevalence of patients with PACS-related cardiopulmonary symptoms (dyspnea, tiredness/fatigue, cough, and chest discomfort) was 16.3%. Several parameters of chest computed tomography and echocardiogram were similar in patients with and without cardiopulmonary symptoms. The multivariate analysis showed that PACS-related cardiopulmonary-symptoms were independently related to female sex (OR 3.023; 95% CI 1.319-6.929), in-hospital deep venous thrombosis (OR 13.689; 95% CI 1.069-175.304), elevated troponin I (OR 1.355; 95% CI 1.048-1.751) and C-reactive protein during hospitalization (OR 1.060; 95% CI 1.023-1.097) and depression (OR 6.110; 95% CI 2.254-16.558). Conclusion PACS-related cardiopulmonary symptoms 90 days post-discharge are common and multifactorial. Beyond thrombotic and markers of inflammation/myocardial injury during hospitalization, female sex and depression were independently associated with cardiopulmonary-related PACS. These results highlighted the need for a multifaceted approach targeting susceptible patients.

Resumo Fundamento A maioria da evidência sobre o impacto da síndrome COVID pós-aguda (PACS, do inglês, post-acute COVID-19 syndrome) descreve sintomas individuais sem correlacioná-los com exames de imagens. Objetivos Avaliar sintomas cardiopulmonares, seus preditores e imagens relacionadas em pacientes com COVID-19 após alta hospitalar. Métodos Pacientes consecutivos, que sobreviveram à COVID-19, foram contatados 90 dias após a alta hospitalar. A equipe de desfechos clínicos (cega quanto aos dados durante a internação) elaborou um questionário estruturado avaliando sintomas e estado clínico. Uma análise multivariada foi realizada abordando a evolução da COVID-19, comorbidades, ansiedade, depressão, e estresse pós-traumático durante a internação, e reabilitação cardíaca após a alta. O nível de significância usado nas análises foi de 5%. Resultados Foram incluídos 480 pacientes (idade 59±14 anos, 67,5% do sexo masculino) que receberam alta hospitalar por COVID-19; 22,3% necessitaram de ventilação mecânica. A prevalência de pacientes com sintomas cardiopulmonares relacionados à PACS (dispneia, cansaço/fadiga, tosse e desconforto no peito) foi de 16,3%. Vários parâmetros de tomografia computadorizada do tórax e de ecocardiograma foram similares entre os pacientes com e sem sintomas cardiopulmonares. A análise multivariada mostrou que sintomas cardiopulmonares foram relacionados de maneira independente com sexo feminino (OR 3,023; IC95% 1,319-6,929), trombose venosa profunda durante a internação (OR 13,689; IC95% 1,069-175,304), nível elevado de troponina (OR 1,355; IC95% 1,048-1,751) e de proteína C reativa durante a internação (OR 1,060; IC95% 1,023-1,097) e depressão (OR 6,110; IC95% 2,254-16,558). Conclusão Os sintomas cardiopulmonares relacionados à PACS 90 dias após a alta hospitalar são comuns e multifatoriais. Além dos marcadores trombóticos, inflamatórios e de lesão miocárdica durante a internação, sexo feminino e depressão foram associados independentemente com sintomas cardiopulmonares relacionados à PACS. Esses resultados destacaram a necessidade de uma abordagem multifacetada direcionada a pacientes susceptíveis.

https://doi.org/10.36660/abc.20220642

Repetibilidade do estudo tomográfico da córnea com Scheimpflug rotacional, em olhos normais, olhos com ceratocone e olhos com ceratocone operados por crosslinking
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Sena Jr., Nelson Batista

; Criado, Guilherme Garcia

; Mazzeo, Thiago J. M. M.

; Oliveira, Thiago Gadelha Valle

; Fonseca Filho, João B. R. da

; Novais, Gustavo Amorim

; Lopes, Bernardo T.

; Ambrósio Jr., Renato

Revista Brasileira de Oftalmologia

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2023, Volume 82 elocation e0029

Resumo: En Pt | Texto: En Pt | PDF: En | PDF: Pt

ABSTRACT Objective To evaluate the accuracy of corneal tomography with Scheimpflug images (Pentacam® AXL, OCULUS, Wetzlar, Germany) in scanning patterns with 25 and 50 images, by analyzing their repeatability and reproducibility in normal eyes, eyes with keratoconus and with keratoconus after crosslinking. Methods Prospective, cross-sectional, mixed study including patients who had normal corneas, or who had keratoconus, who had not undergone corneal surgery, with the exception of crosslinking. Patients who had undergone surgery for intracorneal ring implantation or corneal transplantation were excluded. Three measurements were performed with 25 images and three measurements were performed with 50 images on each eye included in the study. Results The study evaluated a total of 54 eyes of 41 patients. Of these, 10 (18.52%) eyes had normal corneas, without previous eye surgery, 22 (40.74%) were eyes with keratoconus, without previous eye surgery, and 22 (40.74%) were eyes with keratoconus, with crosslinking for keratoconus. In the study of repeatability, we noticed a greater variation of values in all indices in patients with KC compared to those with normal eyes, in most of the parameters analyzed. Conclusion There is no significant difference between the scanning methods with 25 and 50 images. However, 25 scans has advantages that make it the main method suggested. The presence of keratoconus has a negative impact on the repeatability of both types of examination, and there is great agreement between the methods in the three groups studied. The high repeatability coefficient in some parameters suggests that these data should be used with care in the assessment of keratoconus progression.

RESUMO Objetivo Avaliar a precisão da tomografia corneana com imagens de Scheimpflug (Pentacam® AXL, OCULUS, Wetzlar, Alemanha) nos padrões de escaneamento com 25 e 50 imagens, verificando sua repetibilidade e reprodutibilidade em olhos normais, com ceratocone e com ceratocone após crosslinking. Métodos Estudo prospectivo, transversal, misto, no qual foram incluídos os pacientes que tinham córneas normais, ou com ceratocone; e não tinham realizado cirurgias corneanas, com exceção do crosslinking. Foram excluídos os pacientes que tivessem realizado outras cirurgias, como implante de anel intracorneano ou transplante de córnea. Foram realizadas três medidas com 25 imagens e três medidas com 50 imagens em cada olho incluído no estudo. Resultados O estudo avaliou 54 olhos de 41 pacientes. Destes, dez (18,52%) olhos eram com córneas normais e sem cirurgia ocular prévia aleatoriamente selecionados de 5 pacientes; 22 (40,74%) olhos aleatoriamente selecionados de 18 pacientes com ceratocone, sem cirurgia ocular prévia; e 22 (40,74%) olhos com ceratocone de 18 pacientes operados por crosslinking. No estudo da repetibilidade, percebemos uma maior variação de valores em todos os índices nos pacientes com ceratocone comparados aos de pacientes com olhos normais, em grande parte dos parâmetros analisados. Conclusão Não houve diferença significativa entre os métodos de escaneamento por 25 e 50 imagens, sendo o escaneamento por 25 imagens mais conveniente. A presença de ceratocone teve impacto negativo na repetibilidade de ambos os tipos de exame, e foi grande a concordância entre os métodos nos três grupos estudados. O coeficiente de repetibilidade permite considerar a relevância clínica dos dados para avaliar a progressão de ceratocone.

https://doi.org/10.37039/1982.8551.20230029

Chaotic dynamics in memristive circuits
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Iarosz, Kelly C.

; Gabrick, Enrique C.

; Trobia, José

; Borges, Rafael R.

; Protachevicz, Paulo R.

; Bonetti, Robson C.

; de Souza, Silvio L.T.

; Batista, Gabriel L.

; Szezech Jr., José D.

; Caldas, Iberê L.

; Batista, Antonio M.

Revista Brasileira de Ensino de Física

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2023, Volume 45 elocation e20230116

Resumo: En | Texto: En | PDF: En

Memristors (abbreviation of memory and resistor), introduced as the fourth fundamental electrical circuit element, remember the electric charge that flowed through it. These nonlinear elements are considered as a class of two terminal resistive devices and offers a lot of possible applications in various areas. In this article, we review the dynamical behaviour of some electrical circuits with memristors. Initially, we show that a simple circuit with a capacitor and an inductor connected to a memristor exhibits periodic and chaotic attractors. After that, we show that the known Chua circuit, with a nonlinear resistance, can generate bifurcations and chaos. Substituting the nonlinear resistance by a memristor, the modified Chua circuit exhibits coexistence of attractors. Another known circuit, the Colpitts, is made of a combination of capacitors and inductors containing a bipolar junction transistor. We show that the modified Colpitts circuit, created by substituting the transistor by a memristor, presents multistability and coexistence of many attractors.

https://doi.org/10.1590/1806-9126-rbef-2023-0116

Structural, Thermal and Magnetic Characterization of Polycrystalline Ni-Mn-Ga Ferromagnetic Shape Memory Alloys
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Batista, K. V.

; Quirino, J. M.

; Souto, C. R.

; Feitosa, F. R.

; Gomes, R. M.

; Guedes, B.

; Júnior, F. W. E. L. A.

Materials Research

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2023, Volume 26 elocation e20230201

Resumo: En | Texto: En | PDF: En

Shape memory alloys (SMA) are now widely studied in academia and have increasing usage in industry, as they allow efficient performance compared to mechanic actuators with reduced dimensions and the possibility of sensing temperature through the material itself. A subclass of the SMAs are the alloys with magnetic shape memory, still little explored as intelligent materials in Brazil. They combine the best properties of SMAs and common magnetostrictive materials. The magnetic shape memory alloys (MSMA) can be activated not only by the presence of a thermal stimulus, but also by the presence of an applied magnetic field. In this research, the polycrystalline magnetic shape memory alloys Ni51.3Mn24Ga24.7 and Ni54Mn21Ga25 were manufactured and characterized. Differential scanning calorimetry, X-Ray diffraction, energy dispersive X-ray spectrometry and scanning electron microscopy analyzes were performed to thermoanalytically and crystallographically characterize the alloys. Magnetic characterizations were also performed using Magnetic force microscopy. The results of the characterizations showed that the production process and the heat treatment were satisfactory for the fabrication of the ferromagnetic polycrystalline alloys. Besides that, the compositions Ni51.3Mn24Ga24.7 and Ni54Mn21Ga25, presented austenitic and martensitic 5M structures, respectively, at room temperature and it was possible to observe the alignment of the magnetic domains after magnetization.

https://doi.org/10.1590/1980-5373-mr-2023-0201

Development of a Disposable Pipette Extraction Method Using Coffee Silverskin as an Adsorbent for Chromium Determination in Wastewater Samples by Solid Phase Extraction
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Silva, Weida R.

; Costa, Bruno E. S.

; Batista, Alex D.

; Alves, Vanessa N.

; Coelho, Nivia M. M.

Journal of the Brazilian Chemical Society

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Mai 2022, Volume 33 Nº 5 Páginas 498 - 507

Resumo: En | Texto: En | PDF: En

A procedure using disposable pipette tips adapted for solid-phase extraction, known as DPX SPE, was used as an alternative way for the chromium determination in wastewater samples. DPX-SPE consists of a device which allows a dynamic contact between the sample and the solid-phase. A residue obtained from the processing of coffee beans, denominate coffee silverskin, was used as a new adsorbent. Characterization techniques revealed properties of lignocellulosic materials with potential application for chromium adsorption. The parameters including adsorbent mass (25.00 mg), elution solvent (0.1 mol L-1 HCl, 200 μL) and pH (2.0) were optimized. Thus, 1.00 mL of deionized water for conditioning, 4.00 mL of sample, 2 extraction cycles and 1 elution cycle were the employed conditions. Enrichment factor of 12, limit of detection of 6.00 µg L-1 and relative standard deviation (RSD) 1.3% (n = 3) were obtained. The method proved to be fast, cheap, environmentally friendly, and simple, providing good recoveries (104-113%), and it was satisfactorily applied in real samples.

https://doi.org/10.21577/0103-5053.20210171

Milonine attenuates the lipopolysaccharide-induced acute lung injury in mice by modulating the Akt/NF-κB signaling pathways
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BERNARDO, LARISSA R.

; FERREIRA, LAÉRCIA KARLA D.P.

; FERREIRA, LARISSA A.M.P.

; VIEIRA, COSMO ISAÍAS D.

; OLIVEIRA, JOÃO BATISTA DE

; LIMA, LOUISE M. DE

; ALVES, ADRIANO FRANCISCO

; ARAÚJO, RUBENS S.

; MAIA, MAYARA S.

; SCOTTI, MARCUS T.

; BARBOSA FILHO, JOSÉ MARIA

; PIUVEZAM, MARCIA REGINA

Anais da Academia Brasileira de Ciências

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2022, Volume 94 Supl. 4 elocation e20211327

Resumo: En | Texto: En | PDF: En

Abstract Acute lung injury is an inflammation that triggers acute respiratory distress syndrome with perialveolar neutrophil infiltration, alveolar-capillary barrier damage, and lung edema. Activation of the toll-like receptor 4 complex (TLR4/MD2) and its downstream signaling pathways are responsible for the cytokine storm and cause alveolar damage. Due to the complexity of this pulmonary inflammation, a defined pharmacotherapy has not been established. Thus, this study evaluated the anti-inflammatory potential of milonine, an alkaloid of Cissampelos sympodialis Eichl, in an experimental model of lung inflammation. BALB/c mice were lipopolysaccharide-challenged and treated with milonine at 2.0 mg/kg. Twenty-four hours later, the bronchoalveolar fluid, peripheral blood, and lungs were collected for cellular and molecular analysis. The milonine treatment decreased the cell migration (mainly neutrophils) to the alveoli, the pulmonary edema, and the cytokine levels (IL-1β, IL-6, TNF-α). The systemic IL-6 level was also reduced. The milonine docking analysis demonstrated hydrophobic interaction at TLR4/MD2 groove with Ile124 and Phe126 amino acids. Indeed, the alkaloid downregulated the kinase-Akt and NF-κB through TLR4/MD2. Therefore, milonine is an effective inflammatory modulator being a potential molecule for the treatment of lung inflammation.

https://doi.org/10.1590/0001-3765202220211327

10.

Absolute Configuration Reassignment of Natural Products: An Overview of the Last Decade
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Batista, Andrea N. L.

; Angrisani, Bianca R. P.

; Lima, Maria Emanuelle D.

; Silva, Stephanie M. P. Da

; Schettini, Vitória H.

; Chagas, Higor A.

; Santos Jr., Fernando M. dos

; Batista Jr., João M.

; Valverde, Alessandra L.

Journal of the Brazilian Chemical Society

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Ago 2021, Volume 32 Nº 8 Páginas 1499 - 1518

Resumo: En | Texto: En | PDF: En

The assignment of absolute configuration (AC) is a crucial step in the structural characterization of natural products, especially for those subjected to biological assays. Methods such as X-ray crystallography, stereocontrolled organic synthesis, nuclear magnetic resonance (NMR), and chiroptical spectroscopies are commonly used to determine the AC of chiral natural compounds. Even with these well-established techniques, however, unambiguous stereochemical assignments of natural products remain a challenge, resulting in an increasing number of structural misassignments being reported every year. Herein, we will present the main techniques that have been used in AC reassignments of natural products over the last 10 years, along with some selected examples. Special attention will be paid to the strengths and weaknesses of each approach. With this, we expect to provide the readers with critical information to help them to choose the appropriate methods for correct AC determinations.

https://doi.org/10.21577/0103-5053.20210079 142 downloads

11.

Mapping of pathological manifestations in asphalt pavement through the use of drones
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Vasconcelos Fernandes, R. T.

; Fonseca Cabral, A.

; Batista Dantas, G. C.

; Varela Tinoco, V. N.

; Azevedo da Silveira, B. D.

; Sousa Junior, A. M.

Revista ALCONPAT

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Abr 2021, Volume 11 Nº 1 Páginas 61 - 72

Resumo: Es En Pt | Texto: Es En Pt | PDF: Es | PDF: En | PDF: Pt

Resumen El objetivo de este trabajo es estudiar la viabilidad del empleo de Drones para mapear e inspeccionar manifestaciones patológicas en pavimentos asfálticos en comparación con el método tradicional. Se establecieron parcelas muestrales cada 20 m, con 6 m de extensión, totalizando 20 estaciones, las cuales tuvieron sus manifestaciones patológicas anotadas y calculado el Índice Global de Gravedad para el área de estudio. Los resultados obtenidos con las metodologías de referencia y alternativa se confrontaron en función de las patologías identificadas y el tiempo empleado en los levantamientos. Los resultados demostraron viabilidad para el empleo de Drones en la inspección de patologías de pavimentos asfálticos, tomando como base la Norma DNIT 006/2003 - PRO, obteniendo resultados similares a la metodología tradicional con reducción significativa del tiempo de operación (33,3%).

Abstract This work objective is to study the feasibility of the Drones’ use for mapping and inspecting pathological manifestations in asphalt pavements compared to the traditional method. Sampling plots were established every 20 m, with 6 m extension, making a total of 20 stations, which had their pathological manifestations recorded and calculated with the Global Severity Index for the study area. The results obtained by the reference and alternative methodologies were confronted according to the pathologies identified and the time spent in the surveys. The results showed feasibility in the use of drones for inspection of pathologies in asphalt pavements, based on DNIT 006/2003 - PRO, obtaining results similar to those of the traditional methodology with a significant reduction of the time of operation (33.3%).

Resumo Este trabalho objetiva estudar a viabilidade do emprego de Drones para mapeamento e inspeção de manifestações patológicas em pavimentos asfálticos comparando ao método tradicional. Foram estabelecidas parcelas amostrais a cada 20 m, com 6 m de extensão, totalizando 20 estações, as quais tiveram suas manifestações patológicas anotadas e calculado o Índice Global de Gravidade para a área de estudo. Os resultados obtidos pelas metodologias de referência e alternativa foram confrontados em função das patologias identificadas e do tempo gasto nos levantamentos. Os resultados demonstraram viabilidade para emprego de Drones para inspeção de patologias em pavimentos asfálticos, tomando como base a Norma DNIT 006/2003 - PRO, obtendo resultados similares à metodologia tradicional com redução significativa do tempo de operação (33,3%).

https://doi.org/10.21041/ra.v11i1.521 40 downloads

12.

Mathematical modeling and forecasting of COVID-19: experience in Santiago de Cuba province
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Ramirez-Torres, E. E.

; Selva Castañeda, A. R.

; Rodríguez-Aldana, Y.

; Sánchez Domínguez, S.

; Valdés García, L. E.

; Palú-Orozco, A.

; Oliveros-Domínguez, E. R.

; Zamora-Matamoros, L.

; Labrada-Claro, R.

; Cobas-Batista, M.

; Sedal-Yanes, D.

; Soler-Nariño, O.

; Valdés-Sosa, P. A.

; Montijano, J. I.

; Bergues Cabrales, L. E.

Revista mexicana de física

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Fev 2021, Volume 67 Nº 1 Páginas 123 - 136

Resumo: En | Texto: En | PDF: En

Abstract In the province of Santiago de Cuba, Cuba, the COVID-19 epidemic has a limited progression that shows an early small-number peak of infections. Most published mathematical models fit data with high numbers of confirmed cases. In contrast, small numbers of cases make it difficult to predict the course of the epidemic. We present two known models adapted to capture the noisy dynamics of COVID-19 in the Santiago de Cuba province. Parameters of both models were estimated using the approximate-Bayesian-computation framework with dedicated error laws. One parameter of each model was updated on key dates of travel restrictions. Both models approximately predicted the infection peak and the end of the COVID-19 epidemic in Santiago de Cuba. The first model predicted 57 reported cases and 16 unreported cases. Additionally, it estimated six initially exposed persons. The second model forecasted 51 confirmed cases at the end of the epidemic. In conclusion, an opportune epidemiological investigation, along with the low number of initially exposed individuals, might partly explain the favorable evolution of the COVID-19 epidemic in Santiago de Cuba. With the available data, the simplest model predicted the epidemic evolution with greater precision, and the more complex model helped to explain the epidemic phenomenology.

https://doi.org/10.31349/revmexfis.67.123 10 downloads

13.

The Program for Biodiversity Research in Brazil: The role of regional networks for biodiversity knowledge, dissemination, and conservation
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ROSA, CLARISSA

; BACCARO, FABRICIO

; CRONEMBERGER, CECILIA

; HIPÓLITO, JULIANA

; BARROS, CLAUDIA FRANCA

; RODRIGUES, DOMINGOS DE JESUS

; NECKEL-OLIVEIRA, SELVINO

; OVERBECK, GERHARD E.

; DRECHSLER-SANTOS, ELISANDRO RICARDO

; ANJOS, MARCELO RODRIGUES DOS

; FERREGUETTI, ÁTILLA C.

; AKAMA, ALBERTO

; MARTINS, MARLÚCIA BONIFÁCIO

; TOMAS, WALFRIDO MORAES

; SANTOS, SANDRA APARECIDA

; FERREIRA, VANDA LÚCIA

; CUNHA, CATIA NUNES DA

; PENHA, JERRY

; PINHO, JOÃO BATISTA DE

; SALIS, SUZANA MARIA

; DORIA, CAROLINA RODRIGUES DA COSTA

; PILLAR, VALÉRIO D.

; PODGAISKI, LUCIANA R.

; MENIN, MARCELO

; BÍGIO, NARCÍSIO COSTA

; ARAGÓN, SUSAN

; MANZATTO, ANGELO GILBERTO

; VÉLEZ-MARTIN, EDUARDO

; SILVA, ANA CAROLINA BORGES LINS E

; IZZO, THIAGO JUNQUEIRA

; MORTATI, AMANDA FREDERICO

; GIACOMIN, LEANDRO LACERDA

; ALMEIDA, THAÍS ELIAS

; ANDRÉ, THIAGO

; SILVEIRA, MARIA AUREA PINHEIRO DE ALMEIDA

; SILVEIRA, ANTÔNIO LAFFAYETE PIRES DA

; MESSIAS, MARILUCE REZENDE

; MARQUES, MARCIA C.M.

; PADIAL, ANDRE ANDRIAN

; MARQUES, RENATO

; BITAR, YOUSZEF O.C.

; SILVEIRA, MARCOS

; MORATO, ELDER FERREIRA

; PAGOTTO, RUBIANI DE CÁSSIA

; STRUSSMANN, CHRISTINE

; MACHADO, RICARDO BOMFIM

; AGUIAR, LUDMILLA MOURA DE SOUZA

; FERNANDES, GERALDO WILSON

; OKI, YUMI

; NOVAIS, SAMUEL

; FERREIRA, GUILHERME BRAGA

; BARBOSA, FLÁVIA RODRIGUES

; OCHOA, ANA C.

; MANGIONE, ANTONIO M.

; GATICA, AILIN

; CARRIZO, MARÍA CELINA

; RETTA, LUCÍA MARTINEZ

; JOFRÉ, LAURA E.

; CASTILLO, LUCIANA L.

; NEME, ANDREA M.

; RUEDA, CARLA

; TOLEDO, JOSÉ JULIO DE

; GRELLE, CARLOS EDUARDO VIVEIROS

; VALE, MARIANA M.

; VIEIRA, MARCUS VINICIUS

; CERQUEIRA, RUI

; HIGASHIKAWA, EMÍLIO MANABU

; MENDONÇA, FERNANDO PEREIRA DE

; GUERREIRO, QUÊZIA LEANDRO DE MOURA

; BANHOS, AUREO

; HERO, JEAN-MARC

; KOBLITZ, RODRIGO

; COLLEVATTI, ROSANE GARCIA

; SILVEIRA, LUÍS FÁBIO

; VASCONCELOS, HERALDO L.

; VIEIRA, CECÍLIA RODRIGUES

; COLLI, GUARINO RINALDI

; CECHIN, SONIA ZANINI

; SANTOS, TIAGO GOMES DOS

; FONTANA, CARLA S.

; JARENKOW, JOÃO A.

; MALABARBA, LUIZ R.

; RUEDA, MARTA P.

; ARAUJO, PUBLIO A.

; PALOMO, LUCAS

; ITURRE, MARTA C.

; BERGALLO, HELENA GODOY

; MAGNUSSON, WILLIAM E.

Anais da Academia Brasileira de Ciências

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2021, Volume 93 Nº 2 elocation e20201604

Resumo: En | Texto: En | PDF: En

Abstract The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.

https://doi.org/10.1590/0001-3765202120201604 1034 downloads

14.

Processing of an AA7050/Al Hybrid Composites Reinforced with Multiwalled Carbon Nanotubes
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Batista, Luana A.

; Cunha, Thiago H. R. da

; Felisberto, Marcos D. V.

; Cetlin, Paulo R.

; Mazzer, Eric M.

Materials Research

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2021, Volume 24 Nº 5 elocation e20210077

Resumo: En | Texto: En | PDF: En

Abstract The development of carbon nanotubes reinforced metal matrix composites merits relevant attention due to its capacity of improve the hardness and strength of the metal. However, the production of this kind of composite presents many challenges, such as the dispersion and adhesion of carbon nanotubes in the metallic matrix, wich may affect the composite consolidation. The present study aimed the development of composites using an age hardening aluminum alloy reinforced with 0.5 wt.% of multiwalled carbon nanotubes (MWCNT) as well as a hybrid composite based on the mixture of pure aluminum powder and the former composite. AA7050 alloy and pure aluminum matrix composites were processed by ultrasonic mixing, hot pressing and hot extrusion. Subsequently, the materials were submitted to aging heat treatments. The samples were analysed by Scanning Electron Microscopy, X-Ray Diffraction, Atomic Force Spectroscopy, Raman spectroscopy, and Vickers microhardness. It was verified the feasibility in manufacturing the composites by the powder metallurgy route proposed in this work. The AA7050 composite reinforced with 0.5 wt.% MWCNT presented higher hardness than other similar composites in the literature with higher carbon nanotubes content. The aged composite hardness increased 72% in comparison with the present one in the as extruded condition.

https://doi.org/10.1590/1980-5373-mr-2021-0077 4 downloads

15.

Adubação fosfatada na produtividade e qualidade de raízes tuberosas de cultivares de mandioca na savana amazônica, Brasil
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Uchôa, Sandra C. P.

; Nascimento, Fernanda R. do

; Alves, José M. A.

; Melo, Valdinar Ferreira

; Silva, Deyse C. O. da

; Silva, Armando J. da

; Batista, Karine D.

; Matos, Kedma da S.

; Albuquerque, José de A. A. de

Revista de Ciências Agrárias

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Dez 2020, Volume 43 Nº 4 Páginas 21 - 41

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

RESUMO A produtividade de mandioca no Brasil, em 2019, foi de 18 t ha-1, muito aquém do seu potencial. O fósforo é um nutriente determinante da produtividade e encontra-se em níveis muito baixos em solos tropicais. Assim, objetivou-se com este trabalho avaliar doses de fósforo na produtividade e qualidade de raízes tuberosas de cultivares de mandioca na savana amazônica. O experimento foi instalado no delineamento experimental de blocos casualizados, em esquema de parcelas subdivididas, com 4 repetições. Nas parcelas foram aleatorizadas cinco doses de fósforo (0, 45, 90, 180 e 360 kg ha-1 de P2O5) e nas subparcelas duas cultivares de mandioca (Aciolina e Amazonas). Aos 12 meses de cultivo, as raízes tuberosas foram colhidas e avaliadas. O teor de ácido cianídrico não foi influenciado pelos fatores em estudo. O índice de colheita foi dependente, apenas, das cultivares, sendo superior na cv. Amazonas. A cv. Amazonas foi mais produtiva (86 t ha-1), porém, menos eficiente na utilização do P. A produtividade das cultivares Aciolina e Amazonas foram incrementadas em 125 e 82%, até as doses de máxima eficiência técnica de 192 e 208 kg ha-1 de P2O5, respectivamente. Portanto, a adubação fosfatada é uma boa opção para o cultivo da mandioca.

ABSTRACT In 2019, cassava productivity in Brazil was 18 t ha-1, well below its potential. Phosphorus is a nutrient that determines productivity and is found at very low levels in tropical soils. Thus, the objective of this work was to evaluate phosphorus doses in the yield and quality of tuberous roots of cassava cultivars in the Amazonian savanna. The experiment was installed in a randomized block design, in a split-plot scheme, with 4 replications. In the plots, five doses of phosphorus were randomized: 0, 45, 90, 180 and 360 kg ha-1 de P2O5 and in the subplots two cultivars (Aciolina and Amazonas). At 12 months the plants were harvested and the effect of treatments was evaluated. The HCN content was not influenced by the factors under study. The CI was dependent only on the cultivars, being higher in cv. Amazonas. The cv. Amazonas was more productive (86 t ha-1), but less efficient in the use of P. The productivity of the cultivars Aciolina and Amazonas were increased by 125 and 82%, up to the doses of maximum technical efficiency of 192 and 208 kg ha-1 de P2O5, respectively. Therefore, phosphate fertilization is a good option for the cultivation of cassava.

https://doi.org/10.19084/rca.20746 59 downloads

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