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The urgent need for a simple and cost-effective thermochemical process to produce biochar has prompted this study. The aim was to develop a straightforward thermochemical process under O2-limited conditions for the production of coconut-based biochar (CBB) and to assess its ability to remove methylene blue (MB) through adsorption, comparing it with CBB produced by slow pyrolysis. CBBs were obtained under different atmospheric conditions (O2-limited, muffle furnace biochar (MFB); and inert, pyrolytic reactor biochar (PRB)), at 350, 500, and 700 °C, and for 30 and 90'. MFB and PRB were characterized using FTIR, RAMAN, SEM, EDS, and XRD analyses. Adsorption tests were conducted using 1.0 g L-1 of MFB and PRB, 10 mg L-1 of MB at 25 °C for 48 h. Characterization revealed that atmospheric conditions significantly influenced the yield and structural features of the materials. PRB exhibited higher yields and larger cavities than MFB, but quite similar spectral features. Adsorption tests indicated that MFB and PRB had qt values of 33.1 and 9.2 mg g-1, respectively, which were obtained at 700 °C and 90', and 700 °C and 30', respectively. This alternative method produced an innovative and promising lignocellulose-based material with great potential to be used as a biosorbent.

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Three experiments were conducted to evaluate the effects of long-acting injectable progesterone (iP4) in buffalo cows. In Experiment 1, ovariectomized buffaloes received 300 mg (iP300) or 600 mg (iP600) of iP4, and serum P4 concentrations were evaluated. In experiment 2, three groups were compared: control or administration of 300 mg of iP4 3 (iP4-D3) or 6 days (iP4-D6) after timed artificial insemination (TAI). On day 16, reproductive tract was recovered for conceptus, endometrium, and corpus luteum (CL) analysis. In experiment 3, pregnancy per AI (P/TAI) and proportion of pregnancy losses were evaluated after administration of 300 mg of iP4 3 (iP4-D3) or 6 days (iP4-D6) after TAI in lactating buffaloes. In experiment 1, serum P4 concentrations remained over 1 ng/mL for ~ 3 days in both groups. The 300 mg dose was used in subsequent experiments. In experiment 2, CL weight and endometrial glands density were decreased, and conceptus length was increased in iP4-D3 compared to control and to iP4-D6 (P < 0.05). Transcript abundance of Prostaglandin F Receptor (FP) and ISG15 in CL and of ISG15 and MX1 in endometrium was greater in iP4-D3 when compared to control and to iP4-D6 (P < 0.05). In experiment 3, there was no difference among experimental groups for P/TAI at D30 and pregnancy losses (P > 0.1); however, iP4-D3 presented a lower P/TAI at day 60 (41.7%) when compared to control (56.8%) and iP4-D6 (57.7%; P = 0.07). In conclusion, administration iP4 at 3 days after TAI affects CL development and consequently decreases final pregnancy outcome in buffaloes.

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The objective of the present study was to evaluate the effect of estradiol valerate administered at the beginning of the ovulation synchronization protocol on the pregnancy rate of Bos indicus cows. In the experiments, the following products from MSD, Sao Paulo, Brazil were used: estradiol valerate (EV), estradiol benzoate (EB), intravaginal progesterone device (P4), estradiol cypionate (EC), equine chorionic gonadotropin (eCG) and cloprostenol (PGF). In Experiment 1, Bos indicus cows (n=899) with a body condition score (BCS) of 2.76 ± 0.01 were included in a 3 (device) × 2 (protocol: 5 mg of EV or 2 mg of EB) factorial design. There were three types of P4 devices: a new device (New), a device previously used for 9 days (1×), and a device previously used for 18 days (2×). Nine days later (D9), the P4 device was removed, and cows received 300 IU of eCG. In addition, cows in the EB group received 1 mg of EC and 265 µg of PGF. Timed artificial insemination (TAI) was performed 48 h after P4 device removal in the EB group (TAI48) and 54 h after P4 device removal in the EV group (TAI54). In Experiment 2, Bos indicus cows (n=434) with a BCS of 2.62 ± 0.01 received a new P4 device or one previously used for 9 days and 5 mg of EV. On D9, all cows received 300 IU of eCG, and the P4 devices were removed and distributed in TAI48 and TAI54 cows. In Experiment 3, Bos indicus cows (n=429) with a BCS of 2.80 ± 0.01 were divided into the control and EV/EC groups. All cows received a P4 device. In addition, cows in the control group received 2 mg of EB, and cows in the EV/EC group received 5 mg of EV on D0. On D9, all cows received 1 mg of EC and 300 IU of eCG, and the P4 devices were removed. Cows in the control group also received 265 µg of PGF. All cows were inseminated 48 h after the removal of the P4 device. In Experiment 1, there was no effect of the interaction between protocol and P4 device on the occurrence of estrus (P=0.45) or on the pregnancy per artificial insemination ratio (P/AI; P=0.30). In addition, the occurrence of estrus and P/AI were not different between in the two estradiol groups (P=0.12 and P=0.82) and across the types of intravaginal P4 device (P=0.91 and P=0.47). In Experiment 2, the pregnancy rate was lower (tendency) in TAI48 cows (P=0.07). In Experiment 3, the estrus rate (P=0.12) and P/AI (P=0.56) were similar between the experimental groups. In summary, protocols using estradiol valerate without exogenous ovulation induction require adjustments in the timing of AI from 48 to 54 h after P4 device removal. However, a combination of estradiol valerate at the beginning of the protocol and estradiol cypionate nine days later successfully induced ovulation in Bos indicus cows inseminated 48 h after P4 device removal.

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INTRODUCTION: Learning the complex skill of bronchoscopy involves the integration of cognitive domains and motor skills. The development of simulators has opened up new possibilities in bronchoscopy training. This study aimed at evaluating how effective the modeling example methodology is in training this skill and assessed its effect on cognitive load in learning. METHODS: Forty-seven medical students participating in a simulator-based bronchoscopy training program were randomly allocated to a control group, receiving a video lesson, and the modeling example group. They were evaluated by the simulator's metrics at different time points: pre-, posttest, and 15 days and 12 months after training. Cognitive load was assessed with the modified Paas scale. RESULTS: Simulation-based training was effective for both groups, based on simulator metrics (p < .05). The modeling example group outperformed the control group in all measures at posttest and after 15 days (p < .001). After 12 months, there was a decline in skill in both groups, but the modeling example group performed better (p < .001). Simulation-based training reduced cognitive load, more strongly so in the modeling example group (p < .001). CONCLUSION: The modeling example group showed substantial benefits over the control group, both in reducing the cognitive load in learning and in retaining knowledge and skill after 15 days and 12 months.

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Resumo: Introdução: A aprendizagem autorregulada (self-regulated learning - SRL) é o processo ativo que o aluno realiza para atingir seus objetivos de aprendizagem. No ensino médico, pelo fato de o ambiente clínico ser propício para o desenvolvimento da SRL, há potencial benefício na aplicação dessa ferramenta no processo de ensino-aprendizado, embora as diferenças em seus cenários de aplicação exijam uma análise mais aprofundada. Objetivo: Este artigo apresenta uma revisão da literatura sobre o histórico do desenvolvimento da SRL, sua aplicabilidade e avaliação em estudantes de Medicina por meio de escala validada, além dos fatores que a influenciam, como métodos de ensino e questões demográficas e socioculturais. Método: Realizou-se uma busca com o descritor self-regulated learning nas plataformas PubMed e SciELO e na revista Medical Education Online para artigos em inglês publicados entre 2010 e 2021. Resultado: A busca nas bases de dados resultou em 198 artigos, dos quais foram selecionados 100 para a análise crítica. Desses 100 artigos, selecionaram-se 31 que preenchiam os critérios desta revisão. Conclusão: A SRL é um conceito contemporâneo considerado pilar no processo educacional. Trata-se de ferramenta de grande valor em psicologia educacional. A aplicabilidade da SRL no contexto do ensino médico demonstra-se efetiva e traz consigo especificidades sobre a autorregulação do estudante de Medicina. Contudo, são necessários novos estudos acerca do tema, de modo a permitir o desenvolvimento de métodos instrucionais eficazes com sua utilização.

Abstract: Introduction: Self-regulated learning (SRL) is the active process that students perform to achieve their learning goals. In medical education, the development of SRL is favoured by the clinical environment, hence there is potential benefit in applying this tool in the teaching-learning process, although the differences in its application scenarios require deeper analysis. Objective: The aim of this article is to present a literature review on the development of SRL, its applicability and evaluation in medical students using a validated scale, and the factors that influence it, such as teaching methods and demographic and sociocultural issues. Method: A search was performed on the Pub-med and Scielo platforms and the online Medical Education Journal for articles in English published between 2010 and 2021 using the descriptors "Self-regulated learning". Results: The database search resulted in 198 articles, of which 100 were selected for critical analysis. Of these, 31 articles were selected based on meeting the criteria of this review. Conclusions: SRL is a contemporary educational concept and considered a pillar in the educational process. It is a valuable tool in educational psychology. Its applicability in the context of medical education proves to be effective and brings with it specificities in relation to the self-regulation of medical students. However, further studies on the subject are necessary to allow for the development of effective instructional methods to support its use.

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Bronchoscopy is an important procedure to examine the airways. It is traditionally taught by having trainees perform it in humans. This carries risks, albeit rarely, and causes stress to trainees. The objective of this study was to review bronchoscopy simulators, as well as their use in and impact on medical education, presenting perspectives on the use of simulators in the post-pandemic world. This review was based on articles published in English in 2000-2021 and retrieved from any of the following databases: MEDLINE (PubMed), Embase, SciELO, and Google Scholar. Bronchoscopy simulators have improved markedly over time, allowing the teaching/learning process to take place in a risk-free environment. Bronchoscopy simulation training is an interesting option for the evaluation of the airways, especially in the coming years, with the COVID-19 pandemic highlighting the need for continuing medical education.

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ABSTRACT Bronchoscopy is an important procedure to examine the airways. It is traditionally taught by having trainees perform it in humans. This carries risks, albeit rarely, and causes stress to trainees. The objective of this study was to review bronchoscopy simulators, as well as their use in and impact on medical education, presenting perspectives on the use of simulators in the post-pandemic world. This review was based on articles published in English in 2000-2021 and retrieved from any of the following databases: MEDLINE (PubMed), Embase, SciELO, and Google Scholar. Bronchoscopy simulators have improved markedly over time, allowing the teaching/learning process to take place in a risk-free environment. Bronchoscopy simulation training is an interesting option for the evaluation of the airways, especially in the coming years, with the COVID-19 pandemic highlighting the need for continuing medical education.

RESUMO A broncoscopia é um procedimento importante para examinar as vias aéreas. O treinamento tradicional consiste em realizar o procedimento em humanos. Isso traz riscos, embora apenas raramente, e causa estresse nos broncoscopistas em formação. O objetivo deste estudo foi realizar uma revisão da literatura a respeito de simuladores de broncoscopia e seu uso e impacto na educação médica, apresentando perspectivas acerca do uso de simuladores no mundo pós-pandemia. A revisão baseou-se em artigos publicados em inglês em 2000-2021 e recuperados a partir de buscas realizadas nos seguintes bancos de dados: MEDLINE (PubMed), Embase, SciELO e Google Acadêmico. Os simuladores de broncoscopia melhoraram muito ao longo dos anos, permitindo que o processo de ensino e aprendizagem ocorra em um ambiente livre de riscos. O treinamento com simuladores de broncoscopia é uma opção interessante para a avaliação das vias aéreas, principalmente nos próximos anos, já que a pandemia de COVID-19 ressaltou a necessidade de educação médica continuada.

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This study aims at evaluating the efficiency of sensor fusion, based on neural networks, to estimate the microstructural characteristics of both the weld bead and base material in GMAW processes. The weld beads of AWS ER70S-6 wire were deposited on SAE 1020 steel plates varying welding voltage, welding speed, and wire-feed speed. The thermal behavior of the material during the process execution was analyzed using thermographic information gathered by an infrared camera. The microstructure was characterized by optical (confocal) microscopy, scanning electron microscopy, and X-ray Diffraction tests. Finally, models for estimating the weld bead microstructure were developed by fusing all the information through a neural network modeling approach. A R value of 0.99472 was observed for modelling all zones of microstructure in the same ANN using Bayesian Regularization with 17 and 15 neurons in the first and second hidden layers, respectively, with 4 training runs (which was the lowest R value among all tested configurations). The results obtained prove that RNAs can be used to assist the project of welded joints as they make it possible to estimate the extension of HAZ.

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This study evaluated the association between plasma anti-Mullerian hormone (AMH) concentration and fertility in Nelore (Bos indicus) heifers submitted to timed artificial insemination (TAI). At the onset of the synchronization protocol, heifers (n = 289) received a subcutaneous P4 ear implant (3 mg) and 2 mg of oestradiol benzoate. Eight days later, the P4 implant was removed and 0.5 mg of oestradiol cypionate, prostaglandin (0.265 mg, i.m.) and equine chorionic gonadotropin (300 UI, i.m.) was administered, and TAI was performed 48 hr after ear implant removal. Ovarian ultrasound evaluations were performed to measure number of ovarian follicles, dominant follicle size and ovulation response. Pregnancy diagnosis was performed by ultrasound 30 days after AI. Heifers with greater circulating AMH had more antral follicles, a smaller dominant follicle near timed ovulation and lower ovulation response to the timed AI protocol compared to heifers with lower circulating AMH. Although AMH and pregnancy outcome had a quadratic-shaped pattern, AMH was not significantly associated with fertility. In conclusion, heifers with lower AMH had larger follicles towards the end of the synchronization protocol and greater ovulation responses, whereas greater circulating AMH was unrelated to conception success.

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A epiglotite, conhecida recentemente como supraglotite, é uma infecção grave da epiglote e estruturas supraglóticas, com consequente obstrução da via aérea superior e risco iminente de morte. Trata-se de emergência médica, e a via aérea do paciente deve ser garantida o mais breve possível. Com o desenvolvimento e introdução da vacinação contra o Haemophilus influenzae tipo B (Hib), houve queda expressiva de sua incidência e mortalidade na faixa etária pediátrica, principalmente em crianças menores de cinco anos, porém, tal redução não foi tão significativa em adultos. A doença passou a ser mais comum em crianças acima de cinco anos e na faixa etária adulta, e agentes como Streptococcus e Staphylococcus tornaram-se os principais responsáveis. Embora rara, ela ainda não foi eliminada, fazendo-se necessário o seu rápido reconhecimento e tratamento, a fim de evitar mortalidade. (AU)

Epiglottitis, recently known as supraglottitis, is a severe infection of the epiglottis and supraglottic structures, leading to upper airway obstruction and imminent risk of death. It is considered a medical emergency and the patient's airway must be cleared as soon as possible. With the development and introduction of the vaccination against Haemophilus influenzae type B (Hib), there has been a significant decline in its incidence and mortality in the pediatric age range, especially in children younger than five years old, yet not so much in adults. The disease has become more common in children older than five years old and in adults, with Streptococcus and Staphylococcus being the main responsible pathogens. Although it is a rare condition, it has not yet been eradicated, making its fast recognition and treatment necessary to decrease the chance of mortality. (AU)

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