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The application of a versatile approach for modeling and prediction the moisture content of dried peels was evaluated using both empirical and semi-empirical equations (Lewis, Page, Henderson and Pabis, Modified Page, Logarithmic, and Modified Logistic) as well as machine learning models (K-nearest neighbor | KNN, Decision Tree | DT, Artificial Neural Network | ANN and Support Vector Regression | SVR). Heuristic optimization methods, including genetic algorithms (GA) and nonlinear programming (NLP), were employed to identify the best empirical and semi-empirical models for estimating moisture content during the drying process of lemon peel layers. The parameters of the drying kinetics models were optimized using GA to achieve the best results. It was found that as the number of model parameters increases, particularly in models such as the logarithmic one, the optimization problem becomes more complex. Consequently, accurate initial guesses become increasingly important, emphasizing the need for heuristic methods like genetic algorithms. This optimization approach provided excellent performance metrics (R2 > 0.9715, SSR 〈 0.0625 and MSE < 0.0026 for endocarp and R2 〉 0.9678, SSR < 0.0755 and MSE < 0.0030 for epicarp). The models proposed in this study achieved the best results with the modified logistic equation (R2 > 0.9923, MSE 〈 0.0001 and SSR < 0.0013 for endocarp and R2 〉 0.9905, MSE < 0.0001 and SSR < 0.0013 for epicarp). In particular, the multilayer perceptron neural network of the machine learning proved to be the optimal choice as it best accounts for the complexity of the drying kinetics of lemons. This neural network model outperformed traditional empirical and semi-empirical models, demonstrating superior performance metrics (R2 > 0.9979, MSE 〈 0.0002 and SSR < 0.0012 for endocarp and R2 〉 0.9989, MSE < 0.0001 and SSR < 0.0008 for epicarp) when tested against validation data.

Abstract Sleep disruption and negative affect are attendant features of many psychiatric and neurological conditions that are often co-morbid including major depressive disorder, generalized anxiety disorder and chronic pain. Whether there is a causal relationship between negative affect and sleep disruption remains unclear. We therefore asked if mechanisms promoting negative affect can disrupt sleep and whether inhibition of pathological negative affect can normalize disrupted sleep. Signaling at the kappa opioid receptor (KOR) elicits dysphoria in humans and aversive conditioning in animals. We tested the possibility that (a) increased KOR signaling in the anterior cingulate cortex (ACC), a brain region associated with negative emotions, would be sufficient to promote both aversiveness and sleep disruption and (b) inhibition of KOR signaling would normalize pathological negative affect and sleep disruption induced by chronic pain. Chemogenetic Gi-mediated inhibition of KOR-expressing ACC neurons produced conditioned place aversion (CPA) as well as sleep fragmentation in naïve mice. CRISPR/Cas9 editing of ACC KOR normalized both the negative affect and sleep disruption elicited by pathological chronic pain while maintaining the physiologically critical sensory features of pain. These findings suggest therapeutic utility of KOR antagonists for treatment of disease conditions that are associated with both negative affect and sleep disturbances.

Accurate identification of geographical origin and species of wood is crucial for endorsing laws to combat illegal trade. Here, the multi-element profile of Ipê species of economic interest in Brazil was investigated by neutron activation analysis (NAA). Ba, Br, Ca, Ce, Co, Eu, Fe, K, La, Na, Rb, Sc, Sm, Sr and Zn were determined in the heartwood and sapwood tissues. The Random Forest algorithm identified Sr, Ba, Sm, La, Ce and Br as the most important elements for discriminating species. The analyses revealed significant differences between species and wood tissues, indicating that multi-element profile has great potential as a forensic tool. The establishment of comprehensive reference databases that cover large geographical areas and take into account the natural variability between species is fundamental to achieving this goal.

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.

Abstract The software-defined radio has been allowing engineers the possibility of implementing operations on software that were previously only possible to be performed through hardware. With the continuous increase in the processing capacity of computers, it is possible to modify in real time the operating parameters of new radios called Software Defined Radios (SDR) or use commercial devices for other purposes, in addition to those established in their design. By using a low-cost device RTL-SDR R820T2, controlled by a Raspberry Pi 3, with a free software, the present work proposes a characterization procedure in order to collect power levels measurements in a given frequency range with greater accuracy, acting as a spectrum analyzer. Preliminary measures were performed with the device embarked on a drone.

A produção de formas jovens em laboratório é uma etapa fundamental para a implantação e desenvolvimento da aquicultura de pepinos-do-mar. No Brasil, poucos estudos nesse sentido foram realizados, sendo Holothuria grisea considerado o holoturoide com maior potencial para cultivo. Esta tem ocorrência no litoral brasileiro, até Santa Catarina, seu limite sul de distribuição. O objetivo deste trabalho foi avaliar o uso de técnicas para indução à desova e cultivo de larvas de H. grisea, registrando-se seu crescimento, sobrevivência e desenvolvimento. Adultos foram coletados em substrato areno-rochoso na zona entremarés, na Armação do Itapocoroy, Penha, SC, Brasil em fevereiro de 2021. Após determinação do índice gonádico dos reprodutores, foram realizadas indução à desova e fertilização dos ovócitos. As larviculturas foram realizadas em sistema estático, com trocas de água diárias, e foram testados dois métodos: um com troca de água completa e outro com renovação parcial (80%), onde as larvas eram mantidas nas unidades de cultivo. O índice gonádico dos reprodutores apresentou-se baixo (0,85%). Dois exemplares responderam aos estímulos de indução, sendo uma fêmea, que liberou 150.000 ovócitos (135,8µm). Após 48 horas, verificou-se 23,3% de recuperação de larvas auriculárias iniciais (375,5µm). Decorridos 20 dias de experimento, foram observadas larvas auriculárias finais com comprimento médio de 876,8µm (±65,5) e a sobrevivência final foi de 0,51% (±0,04) no tratamento com troca total de água. Já no outro tratamento não houve larvas sobreviventes ao final do experimento. Com este primeiro ensaio de reprodução e larvicultura de H. grisea em seu limite sul de distribuição conclui-se que há possibilidade de induzir a desova e cultivar larvas de H. grisea utilizando técnicas empregadas para outros holoturoides, mesmo com baixo índice gonádico dos reprodutores. Torna-se necessário o prosseguimento de estudos para melhor compreensão do ciclo reprodutivo de H. grisea e determinar protocolos de cultivo adequados para esta espécie.

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High IL-10 levels are pivotal to parasite survival in visceral leishmaniasis (VL). Antigenic stimuli induce IL-10 expression and release of adenosine by CD39/CD73. Due their intrinsic ability to express IL-10 and produce adenosine from extracellular ATP, we evaluated the IL-10, CD39, and CD73 expression by Regulatory T cells (Treg) correlated with VL pathology. Using flow cytometry, Treg cells was analyzed in peripheral blood samples from VL patients (in the presence and absence of Leishmania infantum soluble antigen (SLA)) and healthy individuals (negative endemic control—NEC group), without any treatment. Additionally, IL-10 levels in leukocytes culture supernatant were measured in all groups by ELISA assay. VL patients presented more Treg frequency than NEC group, independently of stimulation. ELISA results demonstrated that SLA induced higher IL-10 expression in the VL group. However, the NEC group had a higher Treg IL-10+ compared to the VL group without stimulation and SLA restored the IL-10 in Treg. Additionally, an increase in Treg CD73+ in the VL group independently of stimuli compared to that in the NEC group was observed. We suggest that Treg are not the main source of IL-10, while the CD73 pathway may be an attempt to modulate the exacerbation of immune response in VL disease.

ABSTRACT Introduction: Pseudothrombocytopenia is an important source of pre-analytical problems in clinical laboratory; therefore it must be correctly evaluated. Low spurious platelet counts can lead to misdiagnosis. Objective: This study aims to study the resolution of pseudothrombocytopenia in the laboratory routine of clinical laboratory by standardizing the use of vortexer. Methods: This is a cross-sectional, analytical, quantitative study based on experimental approach, involving 45 pseudothrombocytopenia samples divided into three groups and submitted to vortexing for 1, 2 and 3 minutes. Results: During the study, 28,435 blood counts were performed, and 56 (0.196%) of these samples confirmed platelet aggregates. The 2 and 3 minute times normalized the platelet count (greater than 150,000/µl) in two thirds of the samples tested. Platelets, hemolysis index, platelet distribution width (PDW) and mean platelet volume (MPV) presented statistically significant mean difference (MD) (p < 0.05) after vortexing at all times. Conclusion: The 2 and 3-minute times were the most effective in the resolution of pseudothrombocytopenia, however, the 2 minutes time should be preferred because it produced fewer effects on the erythrocyte membrane.

Abstract Background In northeastern Brazil, grape pomace has become a potential alternative byproduct because of the recover phenolic compounds from the vinification process. Comparative analyses were performed between lyophilized extract of grape skins from pomace, described as fermented (FGS), and fresh, unfermented (UGS) grape skins to show the relevant brand’s composition upon the first maceration in winemaking. Methods The use of in vitro testing such as Folin-Ciocalteu’s, DPPH free radical scavenger and HPLC methods were performed to evidence antioxidant effect and phenolic compounds. Additionally, vascular reactivity studies were performed in third-order branches of rat superior mesenteric arteries, which were obtained and placed in organ baths containing Krebs-Henseleit solution, maintained at 37 °C, gassed with a mixture of 95% O2 and 5% CO2, and maintained at pH 7.4. The in situ formation of reactive oxygen species (ROS) was evaluated in small mesenteric rings using oxidative fluorescent dihydroethidium dye. Results We found higher phenolic content and antioxidant activity in FGS when compared to UGS. HPLC analyses identified a significant number of phenolic compounds with antioxidant potential in both samples. The vasorelaxant effect induced by FGS was more potent than that induced by UGS, and the activity was attenuated after removal of vascular endothelium or by blockade of endothelium-derived relaxing factors, such as NO and EDHF. Conclusions The FGS extract may be a great source of natural polyphenol products with potent antioxidant effects and endothelium-dependent vasodilatory actions involving NO and EDHF pathways.

Sarcomas represent less than 1% of all solid neoplasms in adults and over 20% in children. Their etiology is unclear, but genetic susceptibility plays an important role in this scenario. Sarcoma is central in Li-Fraumeni Syndrome (LFS), a familial predisposition cancer syndrome. In Brazil, the high prevalence of p.Arg337His mutations in the TP53 gene brings about a unique condition: a cluster of LFS. In the present work, we studied 502 sarcoma patients not selected by age or family history in an attempt to assess the impact of the so-called "Brazilian germline TP53 mutation" (p.Arg337His) on this tumor type. We found that 8% of patients are carriers, with leiomyosarcoma being the main histologic type of sarcoma, corresponding to 52.5% of the patients with the mutated TP53 gene. These findings emphasize the importance of genetic counseling and can better guide the management of sarcoma patients.