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1.
Heliyon ; 10(2): e24047, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38293372

RESUMEN

This work proposes a new methodology to identify and validate deep learning models for artificial oil lift systems that use submersible electric pumps. The proposed methodology allows for obtaining the models and evaluating the prediction's uncertainty jointly and systematically. The methodology employs a nonlinear model to generate training and validation data and the Markov Chain Monte Carlo algorithm to assess the neural network's epistemic uncertainty. The nonlinear model was used to overcome the limitations of the need for big datasets for training deep learning models. However, the developed models are validated against experimental data after training and validation with synthetic data. The validation is also performed through the models' uncertainty assessment and experimental data. From the implementation point of view, the method was coded in Python with Tensorflow and Keras libraries used to build the neural Networks and find the hyperparameters. The results show that the proposed methodology obtained models representing both the nonlinear model's dynamic behavior and the experimental data. It provides a most probable value close to the experimental data, and the uncertainty of the generated deep learning models has the same order of magnitude as that of the nonlinear model. This uncertainty assessment shows that the built models were adequately validated. The proposed deep learning models can be applied in several applications requiring a reliable and computationally lighter model. Hence, the obtained AI dynamic models can be employed for digital twin construction, control, and optimization.

2.
Small ; 20(15): e2304574, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38009795

RESUMEN

Direct selective transformation of greenhouse methane (CH4) to liquid oxygenates (methanol) can substitute energy-intensive two-step (reforming/Fischer-Tropsch) synthesis while creating environmental benefits. The development of inexpensive, selective, and robust catalysts that enable room temperature conversion will decide the future of this technology. Single-atom catalysts (SACs) with isolated active centers embedded in support have displayed significant promises in catalysis to drive challenging reactions. Herein, high-density Ni single atoms are developed and stabilized on carbon nitride (NiCN) via thermal condensation of preorganized Ni-coordinated melem units. The physicochemical characterization of NiCN with various analytical techniques including HAADF-STEM and X-ray absorption fine structure (XAFS) validate the successful formation of Ni single atoms coordinated to the heptazine-constituted CN network. The presence of uniform catalytic sites improved visible absorption and carrier separation in densely populated NiCN SAC resulting in 100% selective photoconversion of (CH4) to methanol using H2O2 as an oxidant. The superior catalytic activity can be attributed to the generation of high oxidation (NiIII═O) sites and selective C─H bond cleavage to generate •CH3 radicals on Ni centers, which can combine with •OH radicals to generate CH3OH.

3.
Heliyon ; 9(10): e20813, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37867888

RESUMEN

Knowledge of odor thresholds is very important for the perfume industry. Due to the difficulty associated with measuring odor thresholds, empirical models capable of estimating these values can be an invaluable contribution to the field. This work developed a framework based on scientific machine learning strategies. A transfer learning-based strategy was devised, where information from a graph convolutional network predicting semantic odor descriptors was used as input data for the feedforward neural network responsible for estimating odor thresholds for chemical substances based on their molecular structures. The predictive performance of this model was compared to a benchmark odor threshold prediction model based on molecular structures that did not utilize transfer learning. Furthermore, the prediction was compared to a correlation previously proposed in the literature and a dummy regressor. Results demonstrated that the transfer learning-based strategy displayed a better predictive performance, suggesting this technique can be useful for predicting odor thresholds.

4.
Syst Rev ; 12(1): 201, 2023 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-37898821

RESUMEN

Food-borne diseases are a global public health issue with 1 in 10 people falling ill after eating contaminated food every year. In response, the food industry has implemented several new pathogen control strategies, such as biotechnological tools using the direct application of bacteriophages for biological control. We have undertaken a systematic review and meta-analysis that evaluated the efficiency of patented phages as a biological control for food-borne pathogens and determined the physical-chemical characteristics of the antimicrobial effect. Included and excluded criteria was developed. Included criteria: Phage patent files with an application in biological control on food and scientific articles and book chapters that used phages patented for food biological control. Excluded criteria: Patent documents, scientific articles, and book chapters that included phage therapy in humans, animals, and biological control on plants but did not have an application on food were not considered in our study. The systematic analysis identified 77 documents, 46 scientific articles, and 31 documents of patents and 23 articles was included in the meta-analysis. Listeria monocytogenes and Salmonella sp. comprised most of the targets identified in the screening, so that we focused on these strains to do the meta-analysis. There are a total of 383 and 192 experiments for Listeria and Salmonella phages for quantitative data analysis.Indexing databases for the bibliographic search (Scopus, Web of Science (WoS) and PubMed (Medline) were addressed by an automated script written in Python 3 Python Core Team (2015) and deposited on GitHub ( https://github.com/glenjasper ).A random-effects meta-analysis revealed (i) significant antimicrobial effect of Listeria phages in apple, apple juice, pear, and pear juice, (ii) significant antimicrobial effect of Salmonella phages in eggs, apple, and ready-to-eat chicken, (iii) no heterogeneity was identified in either meta-analysis, (iv) publication bias was detected for Listeria phages but not for Salmonella phages. (v) ListShield and Felix01 phages showed the best result for Listeria and Salmonella biological control, respectively, (vi) concentration of phage and bacteria, time and food had significant effect in the biological control of Listeria, (vii) temperature and time had a significant effect on the antimicrobial activity of Salmonella phages. The systematic review and meta-analyses to determine the efficiency of bacteriophages previously patented against pathogenic bacteria on dairy products, meat, fruits and vegetables. Besides, the discovering of key factors for efficacy, so that future applications of phage biotechnology in foods can be optimally deployed.


Asunto(s)
Antiinfecciosos , Bacteriófagos , Enfermedades Transmitidas por los Alimentos , Listeria monocytogenes , Bacteriófagos/fisiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Carne
5.
Phys Chem Chem Phys ; 25(43): 29516-29530, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37901907

RESUMEN

We present a theoretical and experimental study of two tetracoordinate Co(II)-based complexes with semi-coordination interactions, i.e., non-covalent interactions involving the central atom. We argue that such interactions enhance the thermal and structural stability of the compounds, making them appropriate for deposition on substrates, as demonstrated by their successful deposition on graphene. DC magnetometry and high-frequency electron spin resonance (HF-ESR) experiments revealed an axial magnetic anisotropy and weak intermolecular antiferromagnetic coupling in both compounds, supported by theoretical predictions from complete active space self-consistent field calculations complemented by N-electron valence state second-order perturbation theory (CASSCF-NEVPT2), and broken-symmetry density functional theory (BS-DFT). AC magnetometry demonstrated that the compounds are field-induced single-ion magnets (SIMs) at applied static magnetic fields, with slow relaxation of magnetization governed by a combination of quantum tunneling, Orbach, and direct relaxation mechanisms. The structural stability under ambient conditions and after deposition was confirmed by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Theoretical modeling by DFT of different configurations of these systems on graphene revealed n-type doping of graphene originating from electron transfer from the deposited molecules, confirmed by electrical transport measurements and Raman spectroscopy.

6.
Artículo en Inglés | MEDLINE | ID: mdl-37835137

RESUMEN

(1) Infrared thermography of the inner canthus of the eye has emerged as a promising tool for temperature screening and fever diagnosis. Its non-invasive nature lends itself well to mass screening in diverse settings such as schools, public transport, and healthcare facilities. Swift and accurate temperature assessment plays a pivotal role in the early identification of potential fever cases, facilitating timely isolation, testing, and treatment, thereby mitigating the risk of disease transmission. Nonetheless, the reliability of this approach in the pediatric population, especially when compared to conventional thermometry methods, remains unexplored. This preliminary study aimed to evaluate the concordance between the temperature of the inner canthus of the eye (Tic,eye), referred to as the brain-eyelid thermal tunnel (BTT°), with axillary and tympanic methods in afebrile children. (2) Methods: A cohort of 36 children, matched in a 1:1 ratio for gender and age, underwent comprehensive assessments encompassing anthropometric data, blood pressure evaluations, axillary (Tax) and tympanic (Tty) temperature measurements, as well as BTT° infrared thermography. (3) Results: The findings revealed a high level of concordance among the tympanic, axillary, and BTT° measurement methods. Bland-Altman plots showed that the bias was minimal, and no statistically significant differences were observed when comparing BTT° with axillary (p = 0.136) and tympanic (p = 0.268) measurements. Passing-Bablok regression scatter plots further confirmed the agreement, aligning the fitted regression line closely with the identity line for both axillary versus BTT° and tympanic (Tty) versus BTT° comparisons. (4) Conclusions: This study holds significant implications for public health, especially in the context of infectious disease outbreaks such as COVID-19. BTT° infrared thermography of the inner canthus of the eye (Tic,eye) reliably measures body temperature in afebrile children in controlled settings; nevertheless, its practical application necessitates the adaptation of biothermodynamic parameters to accommodate diverse environmental conditions.


Asunto(s)
Temperatura Corporal , Termómetros , Humanos , Niño , Temperatura Corporal/fisiología , Reproducibilidad de los Resultados , Fiebre/diagnóstico , Termografía/métodos , Encéfalo , Párpados
7.
J Magn Reson ; 355: 107556, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37751649

RESUMEN

We present a software solution developed in LabVIEW for a home-built High-Frequency Electron Paramagnetic Resonance (HF-EPR) spectrometer. A modular approach was applied to control the spectrometer subsystems and simplify the adaptation to hardware changes during the development. The solution implements measuring procedures for conventional Continuous Wave EPR (CW-EPR), Frequency-Swept EPR (FS-EPR), and Two-Dimensional EPR (2D-EPR) mapping, which are relevant in different cases. The software's automation capabilities were tested in several trial measurements to obtain CW-EPR spectra of Silicon Carbide doped by vanadium (SiC + V) at various temperatures and microwave frequencies, multi-frequency spectra via 2D-EPR mapping, and dense FS-EPR data of a lithium phthalocyanine crystal rotated in a magnetic field. Several prospective modifications of the software are discussed in the conclusion. A modular character allows the easy re-use of code portions in other experimental setups. The spectrometer and the software are currently deployed and utilized in a laboratory of EPR spectroscopy at Central European Institute of Technology (CEITEC) in Brno, and data obtained by it has been already used in a number of publications.

8.
Mar Pollut Bull ; 193: 115184, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37352801

RESUMEN

Studies on novel methodologies addressed to quantification of anthropogenic marine debris (AMD) types ingested by green turtles (Chelonia mydas) is not common in the scientific literature. To fill this gap, we used the alimentary index (IAi) to quantify and classify AMD ingested by green turtles stranded in the Potiguar Basin, northeastern Brazil. We classified 295 green turtles as juveniles (JUV-I (n = 190) and JUV-II (n = 58)) and adults (ADU (n = 47)). We collected gut contents during necropsy and analyzed them using the IAi. The IAi values were categorized as main (IAi ≥ 0.5), secondary (0.25 ≤ IAi < 0.5), and accessory (IAi < 0.25). The results revealed that transparent soft plastic was an accessory item for the three size groups and the second most frequent item (IAi = 0.23) for JUV-I. Our study brings insights into the application of the IAi to evaluate the amount and types of AMD ingested by green turtles.


Asunto(s)
Contenido Digestivo , Tortugas , Animales , Plásticos , Alimentos , Brasil
9.
ACS Omega ; 8(12): 10875-10887, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37008127

RESUMEN

Flavor is an essential component in the development of numerous products in the market. The increasing consumption of processed and fast food and healthy packaged food has upraised the investment in new flavoring agents and consequently in molecules with flavoring properties. In this context, this work brings up a scientific machine learning (SciML) approach to address this product engineering need. SciML in computational chemistry has opened paths in the compound's property prediction without requiring synthesis. This work proposes a novel framework of deep generative models within this context to design new flavor molecules. Through the analysis and study of the molecules obtained from the generative model training, it was possible to conclude that even though the generative model designs the molecules through random sampling of actions, it can find molecules that are already used in the food industry, not necessarily as a flavoring agent, or in other industrial sectors. Hence, this corroborates the potential of the proposed methodology for the prospecting of molecules to be applied in the flavor industry.

10.
Foods ; 12(6)2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36981074

RESUMEN

Flavor is the focal point in the flavor industry, which follows social tendencies and behaviors. The research and development of new flavoring agents and molecules are essential in this field. However, the development of natural flavors plays a critical role in modern society. Considering this, the present work proposes a novel framework based on scientific machine learning to undertake an emerging problem in flavor engineering and industry. It proposes a combining system composed of generative and reinforcement learning models. Therefore, this work brings an innovative methodology to design new flavor molecules. The molecules were evaluated regarding synthetic accessibility, the number of atoms, and the likeness to a natural or pseudo-natural product. This work brings as contributions the implementation of a web scraper code to sample a flavors database and the integration of two scientific machine learning techniques in a complex system as a framework. The implementation of the complex system instead of the generative model by itself obtained 10% more molecules within the optimal results. The designed molecules obtained as an output of the reinforcement learning model's generation were assessed regarding their existence or not in the market and whether they are already used in the flavor industry or not. Thus, we corroborated the potentiality of the framework presented for the search of molecules to be used in the development of flavor-based products.

11.
ACS Omega ; 8(7): 6463-6475, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36844544

RESUMEN

Model-based optimization of simulated moving bed reactors (SMBRs) requires efficient solvers and significant computational power. Over the past years, surrogate models have been considered for such computationally demanding optimization problems. In this sense, artificial neural networks-ANNs-have found applications for modeling the simulated moving bed (SMB) unit but not yet been reported for the reactive SMB (SMBR). Despite ANNs' high accuracy, it is essential to assess its capacity to represent the optimization landscape well. However, a consistent method for optimality assessment using surrogate models is still an open issue in the literature. As such, two main contributions can be highlighted: the SMBR optimization based on deep recurrent neural networks (DRNNs) and the characterization of the feasible operation region. This is done by recycling the data points from a metaheuristic technique-optimality assessment. The results demonstrate that the DRNN-based optimization can address such complex optimization while meeting optimality.

12.
Vaccine ; 40(2): 239-246, 2022 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-34961636

RESUMEN

Over the last few decades, several emerging or reemerging viral diseases with no readily available vaccines have ravaged the world. A platform to fastly generate vaccines inducing potent and durable neutralizing antibody and T cell responses is sorely needed. Bioinformatically identified epitope-based vaccines can focus on immunodominant T cell epitopes and induce more potent immune responses than a whole antigen vaccine and may be deployed more rapidly and less costly than whole-gene vaccines. Increasing evidence has shown the importance of the CD4+ T cell response in protection against HIV and other viral infections. The previously described DNA vaccine HIVBr18 encodes 18 conserved, promiscuous epitopes binding to multiple HLA-DR-binding HIV epitopes amply recognized by HIV-1-infected patients. HIVBr18 elicited broad, polyfunctional, and durable CD4+and CD8+ T cell responses in BALB/c and mice transgenic to HLA class II alleles, showing cross-species promiscuity. To fully delineate the promiscuity of the HLA class II vaccine epitopes, we assessed their binding to 34 human class II (HLA-DR, DQ, and -DP) molecules, and immunized nonhuman primates. Results ascertained redundant 100% coverage of the human population for multiple peptides. We then immunized Rhesus macaques with HIVBr18 under in vivo electroporation. The immunization induced strong, predominantly polyfunctional CD4+ T cell responses in all animals to 13 out of the 18 epitopes; T cells from each animal recognized 7-11 epitopes. Our results provide a preliminary proof of concept that immunization with a vaccine encoding epitopes with high and redundant coverage of the human population can elicit potent T cell responses to multiple epitopes, across species and MHC barriers. This approach may facilitate the rapid deployment of immunogens eliciting cellular immunity against emerging infectious diseases, such as COVID-19.


Asunto(s)
Vacunas contra el SIDA , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/inmunología , Vacunas contra el SIDA/inmunología , Animales , Genes MHC Clase II , Humanos , Macaca mulatta , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos
13.
Rev. bras. med. esporte ; 27(2): 207-211, Apr.-June 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1280070

RESUMEN

ABSTRACT Introduction: Ischemic preconditioning (IPC) has been described in the literature as a resource capable of improving physical performance. Objective: The purpose of this randomized double-blind study was to evaluate the influence of IPC on the neuromuscular performance of trained individuals. Methods: Twenty-four (24) resistance training participants (6 of them women) with a mean age of 25.8 ± 4.6 years were selected and divided into two groups: the upper limb group (ULG) composed of 12 individuals (4 women) and the lower limb group (LLG) composed of 12 individuals (2 women). The maximum repetitions test was applied in the bench press for the ULG and in the 45° leg press for the LLG, with 50% of the one-repetition maximum under control, placebo and IPC conditions, at a random interval of 72 hours between tests. The IPC was applied four hours before the tests by means of an analog sphygmomanometer cuff inflated to 220 mmHg on the arm for the ULG and on the thigh for LLG, with three cycles of five minutes each of ischemia and reperfusion, alternating between the right and left sides. For the placebo, the cuff was inflated to 40 mmHg without causing ischemia. The significance level for the Wilcoxon test was p <0.017, due to the Bonferroni correction. The effect size (ES) was also analyzed. Results: With IPC, the ULG performed 34.8 ± 4.8 repetitions, representing an improvement of 11.29% (IPC vs. control, ES = 0.68 and p = 0.002) and the LLG performed 40.5 ± 15.7 repetitions, representing an improvement of 37.47% (IPC vs. control, ES = 0.84 and p = 0.002). No significant improvements were observed for the placebo in either group. Conclusion: Our data showed that IPC positively influenced neuromuscular performance of both the upper and lower limbs. Level of evidence II; Therapeutic studies investigating the results of treatment (Prospectived comparative studye).


RESUMEN Introducción: El preacondicionamiento isquémico (PCI) ha sido descrito en la literatura como un recurso capaz de mejorar el desempeño físico. Objetivo: El objetivo de este estudio aleatorio doble ciego fue evaluar la influencia del PCI en el desempeño neuromuscular de individuos entrenados. Métodos: Fueron seleccionados 24 individuos (6 mujeres) con promedio de edad de 25,8 ± 4,6 años, practicantes de entrenamiento resistido, divididos en dos grupos, siendo un grupo de miembros superiores (GMS) compuesto por 12 individuos (4 mujeres) y grupo de miembros inferiores (GMI) compuesto por 12 individuos (2 mujeres). El test de repeticiones máximas fue aplicado en el ejercicio de supino para el GMS y en el leg press 45° para el GMI con 50% de una repetición máxima, en las condiciones de control, placebo y PCI, de forma aleatoria con intervalo de 72 horas entre los tests. El PCI fue aplicado cuatro horas antes de los tests mediante un manguito de esfigmomanómetro analógico inflado a 220 mmHg en el brazo para el GMS y en el muslo para el GMI, siendo tres ciclos de cinco minutos de isquemia y cinco minutos de reperfusión, alternando los lados derecho e izquierdo. Para el placebo, el manguito quedó en 40 mmHg, sin provocar isquemia. El nivel de significancia del test de Wilcoxon fue p <0,017, debido a la corrección de Bonferroni. El tamaño del efecto (TE) también fue analizado. Resultados: Con el PCI, el GMS realizó 34,8 ± 4,8 repeticiones, representando mejora de 11,29% (PCI vs control, TE = 0,68 y p = 0,002) y el GMI realizó 40,5 ± 15,7 repeticiones, representando mejora de 37,47% (PCI vs control, TE = 0,84 y p = 0,002). Con el placebo, ambos grupos no mostraron mejora. Conclusión: Nuestros datos mostraron que el PCI influenció positivamente el desempeño neuromuscular tanto de miembros superiores como inferiores. Nivel de evidencia II; Estudios terapéuticos: investigación de los resultados del tratamiento (estudio comparativo prospectivo).


RESUMO Introdução: O pré-condicionamento isquêmico (PCI) tem sido descrito na literatura como um recurso capaz de melhorar o desempenho físico. Objetivo: O objetivo deste estudo randomizado duplo cego foi avaliar a influência do PCI no desempenho neuromuscular de indivíduos treinados. Métodos: Foram selecionados 24 indivíduos (6 mulheres) com média de idade de 25,8 ± 4,6 anos, praticantes de treinamento resistido, divididos em dois grupos, sendo um grupo de membros superiores (GMS), composto por 12 indivíduos (4 mulheres) e grupo de membros inferiores (GMI), composto por 12 indivíduos (2 mulheres). O teste de repetições máximas foi aplicado no exercício de supino para o GMS e no leg press 45° para o GMI com 50% de uma repetição máxima, nas condições de controle, placebo e PCI, de forma aleatória com intervalo de 72 horas entre os testes. O PCI foi aplicado quatro horas antes dos testes por meio de um manguito de esfigmomanômetro analógico inflado a 220 mmHg no braço para o GMS e na coxa para o GMI, sendo três ciclos de cinco minutos de isquemia e cinco minutos de reperfusão, alternando os lados direito e esquerdo. Para o placebo, o manguito ficou em 40 mmHg, sem provocar isquemia. O nível de significância do teste de Wilcoxon foi de p < 0,017, devido à correção de Bonferroni. O tamanho do efeito (TE) também foi analisado. Resultados: Com o PCI, o GMS realizou 34,8 ± 4,8 repetições, representando melhora de 11,29% (PCI vs. controle, TE = 0,68 e p = 0,002) e o GMI realizou 40,5 ± 15,7 repetições, representando melhora de 37,47% (PCI vs. controle, TE = 0,84 e p = 0,002). Com o placebo, ambos os grupos não apresentaram melhora. Conclusão: Nossos dados mostraram que o PCI influenciou positivamente o desempenho neuromuscular tanto de membros superiores quanto inferiores. Nível de evidência II; Estudos terapêuticos-Investigação dos resultados do tratamento (Estudo prospectivo comparativo).


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Adulto Joven , Precondicionamiento Isquémico , Fuerza Muscular/fisiología , Rendimiento Atlético/fisiología , Entrenamiento Aeróbico/métodos , Músculos/irrigación sanguínea , Resistencia a la Tracción , Método Doble Ciego , Prueba de Esfuerzo/métodos
14.
Biota Neotrop. (Online, Ed. ingl.) ; 21(3): e20201159, 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1249084

RESUMEN

Abstract: This study monitored marine turtle nests in a region known as the Potiguar Basin, which stretches from the northern region of Rio Grande do Norte State (5°4'1.15" S, 36°4'36.41" W) to eastern Ceará State (4°38'48.28" S, 37°32'52.08" W) in Brazil. We collected data from January 2011 to December 2019 to identify species of sea turtles that spawn in the basin, to analyze the nesting spatial-temporal pattern and nests characteristics, and to record effects of environmental and anthropic factors on nests. A field team examined sea turtle tracks and nests signs. Turtle clutches were monitored daily until hatchings emerged from the nests. We monitored nests of hawksbill (Eretmochelys imbricata; n = 238) and olive Ridley turtles (Lepidochelys olivacea; n = 103). The nesting season for E. imbricata occurred between December and May and for L. olivacea from March to August. Hawksbills had clutch size, incubation time, number of unhatched eggs, and dead hatchlings higher than olive Ridley turtles; nevertheless, they presented lower hatching success. Precipitation between 0 and 22 mm and relative humidity (RH) higher than 69% increased the hatching success rate for E. imbricata; however, rainfall above 11 mm and RH 64% had the same effect for L. olivacea. Signs of egg theft and human presence (e.g. vehicle traffic and plastic residues on the beach) were recorded and are considered threats to nests. The results of our long-term monitoring study in the Potiguar Basin provide basis for the implementation of mitigation measures and adoption of management policies at nesting beaches in this Brazilian region.


Resumo: Este estudo permitiu o monitoramento de ninhos de tartarugas marinhas em uma região conhecida como Bacia Potiguar, que se estende da região norte do Estado do Rio Grande do Norte (5 ° 4'1,15 "S, 36 ° 4'36,41" W) até o leste do Estado do Ceará (4 ° 38'48,28 "S, 37 ° 32'52,08" W), no Brasil. Coletamos dados de janeiro de 2011 a dezembro de 2019 com o objetivo de identificar as espécies de tartarugas marinhas que desovam na bacia, analisar o padrão espaço-temporal de nidificação, as características dos ninhos, e registrar os efeitos de fatores ambientais e antrópicos. Uma equipe de campo examinou rastros de tartarugas marinhas e sinais de ninhos. As ninhadas das tartarugas foram monitoradas diariamente até que os filhotes emergissem dos ninhos. Monitoramos ninhos de tartarugas-de-pente (Eretmochelys imbricata; n = 238) e tartarugas-oliva (Lepidochelys olivacea; n = 103). A época de nidificação para E. imbricata ocorreu entre dezembro e maio e para L. olivacea de março a agosto. Tartarugas-de-pente apresentaram maior tamanho das ninhadas, tempo de incubação, número de ovos não eclodidos e número de filhotes mortos quando comparado com tartarugas-oliva; no entanto, apresentaram menor sucesso de eclosão. Precipitação entre 0 e 22 mm e umidade relativa (UR) maior que 69% aumentaram a taxa de sucesso de eclosão para E. imbricata; entretanto, chuvas acima de 11 mm e UR 64% tiveram o mesmo efeito para L. olivacea. Sinais de roubo de ovos e presença humana (por exemplo, tráfego de veículos e resíduos de plástico na praia) foram registrados e são considerados ameaças aos ninhos. Os resultados do nosso estudo de monitoramento de longo prazo na Bacia Potiguar fornecem base para a implementação de medidas de mitigação e adoção de políticas públicas em praias de desova nesta região brasileira.

16.
Dalton Trans ; 49(16): 5228-5240, 2020 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-32239049

RESUMEN

To investigate the magnetic properties and the spin entanglement of dinuclear arrays, we prepared compounds [{Cu(pAB)(phen)H2O}2·NO3·pABH·2H2O], 1, and [Cu2(pAB)2(phen)2pz]n, 2 (pABH = p-aminobenzoic acid, phen = 1,10-phenanthroline and pz = pyrazine). The structure of 1 is known and we report here that of 2. They contain similar dinuclear units of CuII ions with 1/2-spins S1 and S2 bridged by pairs of pAB molecules, with similar intradinuclear exchange and fine interactions , but different 3D crystal arrays with weak interdinuclear exchange J', stronger in 2 than in 1. To investigate the magnetic properties and the spin entanglement produced by J', we collected the powder spectra of 1 and 2 at 9.4 GHz and T between 5 and 298 K, and at 34.4 GHz and T = 298 K and single-crystal spectra at room T and 34.4 GHz as a function of magnetic field (B0) orientation in three crystal planes, calculating intradinuclear magnetic parameters J(1)0 = (-75 ± 1) cm-1, J(2)0 = (-78 ± 2) cm-1, |D(1)| = (0.142 ± 0.006) cm-1, |D(2)| = (0.141 ± 0.006) cm-1 and E(1) ∼ E(2) ∼ 0. Single crystal data indicate a quantum entangled phase in 2 around the crossing between two fine structure EPR absorption peaks within the spin triplet. This phase also shows up in powder samples of 2 as a U-peak collecting the signals of the entangled microcrystals, a feature that allows estimating |J'|. Transitions between the two quantum phases are observed in single crystals of 2 changing the orientation of B0. We estimate interdinuclear exchange couplings |J'(1)| < 0.003 cm-1 and |J'(2)| = (0.013 ± 0.005) cm-1, in 1 and 2, respectively. Our analysis indicates that the standard approximation of a spin Hamiltonian with S = 1 for the dinuclear spectra is valid only when the interdinuclear coupling is large enough, as for compound 2 (|J'(2)/J(2)0| ∼ 1.7 × 10-4). When J' is negligible as in 1, the real spin Hamiltonian with two spins 1/2 has to be used. Broken-symmetry DFT predicts correctly the nature and magnitude of the antiferromagnetic exchange coupling in 1 and 2 and ferromagnetic interdinuclear coupling for compound 2.

17.
Dalton Trans ; 49(14): 4425-4440, 2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32176762

RESUMEN

A structurally new heptadentate derivative of a 15-membered pyridine-based macrocycle containing two benzimidazol-2-yl-methyl N-pendant arms (L = 3,12-bis((1H-benzimidazol-2-yl)methyl)-6,9-dioxa-3,12,18-triazabicyclo[12.3.1]octadeca-1(18),14,16-triene) was synthesized and its complexes with the general formula [M(L)](ClO4)2·1.5CH3NO2 (M = MnII (1), FeII (2), CoII (3) and NiII (4)) were thoroughly investigated. X-ray crystal structures confirmed that all complexes are seven-coordinate with axially compressed pentagonal bipyramidal geometry having the largest distortion for NiII complex 4. FeII, CoII and NiII complexes 2, 3 and 4 show rather large magnetic anisotropy manifested by moderate to high obtained values of the axial zero-field splitting parameter D (7.9, 40.3, and -17.2 cm-1, respectively). Magneto-structural correlation of the FeII, CoII and NiII complexes with L and with previously studied structurally similar ligands revealed a significant impact of the functional group in pendant arms on the magnetic anisotropy especially that of the CoII and NiII complexes and some recommendations concerning the ligand-field design important for anisotropy tuning in future. Furthermore, complex 3 showed field-induced single-molecule magnet behavior described with the Raman (C = 507 K-n s-1 for n = 2.58) relaxation process. The magnetic properties of the studied complexes were supported by theoretical calculations, which very well correspond with the experimental data of magnetic anisotropy. Electrochemical measurements revealed high positive redox potentials for M3+/2+ couples and high negative redox potentials for M2+/+ couples, which indicate the stabilization of the oxidation state +ii expected for the σ-donor/π-acceptor ability of benzimidazole functional groups.

18.
Rev. bras. educ. méd ; 43(3): 170-177, jul.-set. 2019. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1003433

RESUMEN

ABSTRACT Background Medical education has evolved considerably over the last few years, especially through adoption of new technologies and active methodologies. These methodologies aim to improve learning and engage students deeply in the process. TBL is a methodology widely used in health schools, including Medical Schools. We can use it to work with large groups, divided into small teams. The students first work individually, then within teams, and finally the groups cooperate to solve applied problems. Objectives To describe students' perceptions and satisfaction about a Medical Genetics course organized into blocks of subject in which we used TBL sessions with first-year medical students. Methods A Medical Genetics course were organized into subject blocks in which a TBL session was conducted in each of these blocks to improve the learning process. At the end of the course, the students answered a questionnaire on satisfaction and perceptions. Results By the first time we described a Medical Genetics course organized into 5 blocks of subject matter on a total of 25 genetic diseases in which a TBL session was conducted in each of these blocks. We enrolled a total of 290 participants and 96% of the students were satisfied with TBL. Furthermore, 97% of students believe that TBL helped them to learn, and 87% approved of use of TBL in the future at other stages of their medical course. Conclusion Application of the TBL method during a medical genetics course was well-received by students and proved an important tool in the structures of curricula for medical education at this university.


RESUMO Introdução A educação médica evoluiu consideravelmente nos últimos anos, especialmente através da adoção de novas tecnologias e metodologias ativas. Essas metodologias visam melhorar a aprendizagem e envolver os alunos profundamente no processo. O TBL é uma metodologia amplamente utilizada em escolas de saúde, incluindo escolas médicas. Podemos usá-lo para trabalhar com grandes grupos, divididos em pequenas equipes. Primeiro, os alunos trabalham individualmente, depois dentro das equipes e, finalmente, os grupos cooperam para resolver os problemas aplicados. Objetivos Descrever as percepções e a satisfação dos alunos em relação a um curso de Genética Médica organizado em blocos de assuntos em que utilizamos sessões de TBL com estudantes de medicina do primeiro ano. Métodos Um curso de Genética Médica foi organizado em blocos de assuntos em que uma sessão de TBL foi realizada em cada um desses blocos para melhorar o processo de aprendizagem. No final do curso, os alunos responderam a um questionário sobre satisfação e percepções. Resultados Pela primeira vez nós descrevemos um curso de Genética Médica organizado em 5 blocos de assuntos, compreendendo 25 doenças genéticas, nos quais, uma sessão de TBL foi conduzida em cada um desses blocos. Participaram um total de 290 alunos, dos quais 96% estavam satisfeitos com o método de TBL. Além disso, 97% dos estudantes acreditam que o TBL os ajudou a aprender, e 87% aprovaram o uso do TBL no futuro, em outras etapas de seu curso de medicina. Conclusão A aplicação do método TBL durante um curso de genética médica foi bem recebida pelos estudantes e se mostrou uma ferramenta importante na estruturação curricular para a educação médica nesta universidade.

19.
Epidemiol Serv Saude ; 28(1): e2018184, 2019 02 18.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-30785574

RESUMEN

OBJECTIVE: to describe spatial patterns of intentional homicides in João Pessoa, Paraíba, Brazil, 2011-2016. METHODS: this was an ecological study using census tracts as units of analysis; the study used data on intentional homicides of victims living in João Pessoa obtained by cross-checking Mortality Information System SIM information with Public Security information; mortality coefficients were calculated for the whole period and its triennia and were later smoothed using the local empirical Bayesian method; spatial autocorrelation techniques were applied to the smoothed coefficients which were using Moran's spatial statistics. RESULTS: significant spatial autocorrelation was detected for the period as a whole I=0.679, p=0.01, the 1st triennium I=0.508, p=0.01, and the 2nd triennium I=0.572, p=0.01; areas of greater risk were identified distributed among the western, northwestern, southeastern, and far south zones of the city, mainly in regions with low socioeconomic conditions; census tracts with low coefficients were located in areas of medium/high socioeconomic status. CONCLUSION: homicides in João Pessoa were high in poor districts and these are priority areas for intervention.


Asunto(s)
Homicidio/estadística & datos numéricos , Áreas de Pobreza , Análisis Espacial , Teorema de Bayes , Brasil , Homicidio/economía , Humanos , Factores de Riesgo , Factores Socioeconómicos
20.
Phys Chem Chem Phys ; 21(8): 4394-4407, 2019 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-30729962

RESUMEN

We report the preparation, X-ray structure, chemical properties, and electron paramagnetic resonance (EPR) studies at Q and X-bands and temperature (mainly) T = 293 K of powder and oriented single crystal samples of the new compound [Cu(N',N'-dimethyl-N'-benzoylthiourea)(2,2'-bipyridine)Cl], called CuBMB. The EPR spectra of single crystal samples at the Q-band display abrupt merging and narrowing of the peaks corresponding to two rotated copper sites as a function of magnetic field (B0) orientation. This behaviour indicates a quantum transition from an array of quasi-isolated spins to a quantum-entangled spin array associated with exchange narrowing processes and produced by weak intermolecular exchange interactions Ji between neighbour copper spins. This transition occurs when the magnitudes of the anisotropic contributions to the Zeeman couplings, tuned with the direction of B0, approach these |Ji| and produce level crossings. The exchange couplings between neighbour spins are estimated from the angular variation of the single crystal EPR results at the Q-band. We analyse the quantum behaviour and phase transitions of the spin system and discuss the magnitudes of the exchange couplings in terms of the structure of the chemical paths connecting Cu neighbours. The single crystal data at the Q-band indicates an uncommon ground electronic state of CuII which is discussed and compared with the results of DFT calculations. The spectrum of polycrystalline (powder) samples at the Q-band is a sum of contributions of microcrystals in each phase, and the fraction F of the entangled phase depends on the microwave frequency. The X-band spectrum is compatible with the Q-band results, but does not display a transition, and the spin system is in the quantum-entangled phase for all field orientations. This behaviour is further studied with a simple geometric model giving basic predictions. The crystal structure of CuBMB is monoclinic, space group P21/n, with a = 11.9790(3) Å, b = 14.0236(5) Å, c = 12.1193(3) Å, ß = 104.952(2)° and Z = 4, and the copper ions are equatorially bonded to the benzoylthiourea and bipyridine ligands in a heavily distorted square pyramidal structure.

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