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1.
Braz J Biol ; 84: e281628, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109719

RESUMO

The increasing need for sustainable alternatives to synthetic insecticides has driven the analysis of extracts from Solanum habrochaites, a wild tomato, through fractionated column chromatography. Potential bioactive compounds for pest management, a clean and promising biotechnological solution, have been reported from this plant. The objective is to provide detailed gas chromatography data, including peaks, structural formulas, and retention indices for the extracts of S. habrochaites aerial parts. Column chromatographic analysis was conducted with five fractions (F1, F2, F5, F3, and F4) of S. habrochaites extracts. Long-chain hydrocarbons such as hexadecanoic acid and docosano were identified in the F1 fraction; fatty acid esters, including hexadecanoate and octadecenoate ethyls in the F2 and methyl ketones, with tridecan-2-one as the major component in the F5, while no identifiable compounds were disclosed in the F3 and F4 fractions. The column chromatography provided valuable insights into compounds in the F1, F2, and F5 fractions of S. habrochaites extracts, highlighting fatty acid esters, long-chain hydrocarbons, and methyl ketones. The bioactive compounds, from extracts of this plant, including the first record of the docosanoate, hexadecanoate and octadecanoate ethyls in S. habrochaites and Solanaceae, reinforces their promising biological application in different areas of science.


Assuntos
Extratos Vegetais , Solanum , Extratos Vegetais/química , Solanum/química , Cromatografia Gasosa , Ácidos Graxos/análise
2.
Phys Rev E ; 109(1-1): 014122, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38366433

RESUMO

In this paper we study a quantum Otto thermal machine where the working substance is composed of N identical qubits coupled to a single mode of a bosonic field, where the atoms and the field interact with a reservoir, as described by the so-called open Dicke model. By controlling the relevant and experimentally accessible parameters of the model we show that it is possible to build a universal quantum heat machine (UQHM) that can function as an engine, refrigerator, heater, or accelerator. The heat and work exchanges are computed taking into account the growth of the number N of atoms as well as the coupling regimes characteristic of the Dicke model for several ratios of temperatures of the two thermal reservoirs. The analysis of quantum features such as entanglement and second-order correlation shows that these quantum resources do not affect either the efficiency or the performance of the UQHM based on the open Dicke model. In addition, we show that the improvement in both efficiency and coefficient of performance of our UQHM occurs for regions around the critical value of the phase transition parameter of the model.

3.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469329

RESUMO

Abstract Horismenus camobiensis sp. nov. (Hymenoptera: Eulophidae), is described based on morphological, molecular and ecological data; this new species of chalcid wasp acts as hyperparasitoid of Opsiphanis invirae (Hübner, 1818) (Lepidoptera: Nymphalidae) in its parasitoid Cotesia invirae Salgado-Neto and Whitfield, 2019 (Hymenoptera: Braconidae). Diagnoses with morphological and molecular characters and illustrations are provided.


Resumo Horismenus camobiensis sp. nov. (Hymenoptera: Eulophidae) é descrita com base em dados morfológicos, moleculares e ecológicos; esta nova espécie Chalcididae atua como hiperparasitoide de Opsiphanis invirae (Hübner, 1818) (Lepidoptera: Nymphalidae) em pupas de seu parasitoide Cotesia invirae Salgado-Neto and Whitfield, 2019 (Hymenoptera: Braconidae). Caracteres diagnósticos morfológicos e moleculares e ilustrações de H. camobiensis são fornecidos.

4.
Braz. j. biol ; 84: e249008, 2024. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355893

RESUMO

Abstract Horismenus camobiensis sp. nov. (Hymenoptera: Eulophidae), is described based on morphological, molecular and ecological data; this new species of chalcid wasp acts as hyperparasitoid of Opsiphanis invirae (Hübner, 1818) (Lepidoptera: Nymphalidae) in its parasitoid Cotesia invirae Salgado-Neto and Whitfield, 2019 (Hymenoptera: Braconidae). Diagnoses with morphological and molecular characters and illustrations are provided.


Resumo Horismenus camobiensis sp. nov. (Hymenoptera: Eulophidae) é descrita com base em dados morfológicos, moleculares e ecológicos; esta nova espécie Chalcididae atua como hiperparasitoide de Opsiphanis invirae (Hübner, 1818) (Lepidoptera: Nymphalidae) em pupas de seu parasitoide Cotesia invirae Salgado-Neto and Whitfield, 2019 (Hymenoptera: Braconidae). Caracteres diagnósticos morfológicos e moleculares e ilustrações de H. camobiensis são fornecidos.


Assuntos
Animais , Vespas , Borboletas , Himenópteros , Pupa
5.
Percept Mot Skills ; 130(6): 2327-2342, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37654231

RESUMO

Mechanical vibration of the Achilles tendon is widely used to analyze the role of proprioception in postural control. The response to this tendon vibration (TV) has been analyzed in the upright posture, but the feet positions have varied in past research. Moreover, investigators have addressed only temporal parameters of the center of pressure (CoP). We investigated the effect of TV on both temporal and spectral characteristics of the CoP motion. Eighteen healthy young adults, stood barefoot, with one foot on each side of a dual platform, wearing glasses with opaque lenses. We applied 20 seconds of Achilles TV (bilaterally with inertial vibrators at a frequency of 80 Hz and an amplitude of .2-.5 mm). We analyzed CoP signals pre-vibration (PRE,4-seconds), during vibration (VIB,20 seconds), and after vibration cessation (REC,20 seconds). We repeated this protocol in natural and standardized positions (15° feet angular opening). For determining CoP amplitude and velocity, we divided the 20 seconds into five phases of four seconds each and calculated spectral parameters for the whole 20-second signals. There was an adaptation process in the speed of the CoP mediolateral (p < .01) and anteroposterior (p < .01) and in the displacement of the CoP anteroposterior (p < .01), with higher values in the VIB condition. Velocity and displacement decreased progressively in the REC condition. Median and peak frequencies were higher in the VIB condition when compared to the REC condition, but only in the mediolateral direction (p = .01). The standardized foot position led to increased speed in CoP mediolateral, anteroposterior, and mediolateral displacement (p < .01). CoP spectral characteristics were not affected by foot positioning. We concluded that adaptation of CoP motion in the presence of TV and after its cessation are observable both in time and frequency domains. Feet positioning influenced CoP motion in the presence of TV and after its cessation but it did not affect its spectral characteristics.


Assuntos
Tendão do Calcâneo , Adulto Jovem , Humanos , Tendão do Calcâneo/fisiologia , Vibração , Propriocepção/fisiologia , Equilíbrio Postural/fisiologia , Posição Ortostática
7.
Public Health ; 209: 39-45, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35797895

RESUMO

OBJECTIVE: The purpose of this study was to investigate the association between the frequency of leisure-time physical activity and brachial pulse pressure (PP), according to physical activity intensity and type, sex, and age, in the general Brazilian population. STUDY DESIGN: This was a cross-sectional study based on data from the Brazilian 2013 National Health Survey. METHODS: The sample consisted of 20,058 men and 20,600 women aged between 18 and 65 years. The frequency of leisure-time physical activity was obtained through a questionnaire and classified according to intensity (vigorous or moderate) and type (cyclic or acyclic). We calculated PP as the difference between systolic and diastolic blood pressures based on the measure of a digital pressure device. Multiple linear regression analysis was applied to analyze the association of different sexes, frequency, type, and intensity of leisure-time physical activity and PP. RESULTS: Adjusted results showed that one session of moderate physical activity per week could benefit men's PP: ß = -1.87 mmHg; SE = 0.83. For women, the adjusted model reveals that physical activity undertaken twice a week is sufficient to benefit PP: ß = -1.77 mmHg; SE = 0.72. However, according to type, two times a week of acyclic activities increased PP in men: ß = 2.62 mmHg; SE = 0.62 and decreased in women: ß = -2.67 mmHg; SE = 0.72. CONCLUSIONS: Our results suggest that low frequencies of leisure-time physical activity are sufficient to induce beneficial effects on the cardiovascular system for both sexes. Also, there are some differences between sexes in cardiac adaptations according to type, frequency, and intensity of physical activity.


Assuntos
Exercício Físico , Atividades de Lazer , Adolescente , Adulto , Idoso , Pressão Sanguínea , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Braz J Biol ; 84: e249008, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35081213

RESUMO

Horismenus camobiensis sp. nov. (Hymenoptera: Eulophidae), is described based on morphological, molecular and ecological data; this new species of chalcid wasp acts as hyperparasitoid of Opsiphanis invirae (Hübner, 1818) (Lepidoptera: Nymphalidae) in its parasitoid Cotesia invirae Salgado-Neto and Whitfield, 2019 (Hymenoptera: Braconidae). Diagnoses with morphological and molecular characters and illustrations are provided.


Assuntos
Borboletas , Himenópteros , Vespas , Animais , Pupa
9.
Braz. j. biol ; 82: 1-7, 2022. graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468494

RESUMO

Agroecological production represents a new reality in vegetable farming. Thus, the study aimed to search for the presence of pesticides in agroecological samples and microbiological and parasitological contamination in Lactuca sativa L. of agroecological and conventional fairs in Alagoas. Thirty-two samples were collected, a hygienic sanitary checklist was performed, along with coliform, Salmonella spp., Staphylococcus aureus research and Gas Chromatography with Mass Spectrometer (GC-MS) for pesticide research; using two methodologies for parasitological studies. Thirty-two samples were analyzed, with a sanitary adequacy level at 45% and 38% for fairs (agroecological and conventional) respectively, with three samples (9.4%) in total, being adequate to the microbiological pattern according to RDC no. 12/2001. Among the 23 samples which were tested positive for parasites, 69.5% originated from samples extracted at conventional fairs, and 53% of every positive samples presented Entamoeba coli as the main contaminant. All together, no traces of deltamethrin were detected, but in two of the samples a peak retention for diphenoconazole was detected. In conclusion, the fairs represent an adequate environment for human pathogens and indicators. Therefore greater hygiene training of vegetable traders and consumers in the state of Alagoa sis required, especially in conventional fairs, which presented more critical microbiological and parasitological indexes comparing to fairs with agroecological products; however, the presence of difenoconazole in two samples of agricultural fairs suggests accidental contamination or indiscriminate use of this chemical in the production of Lactuca sativa, however, products with agroecological origin represents a better choice for the consumers.


A produção agroecológica representa uma nova realidade no cultivo das hortaliças. Assim, o estudo teve como objetivo verificar a presença de agrotóxicos em amostras agroecológicas e analisar a contaminação microbiológico e parasitológico em Lactuca sativa L. de feiras agroecológicas e convencionais de Alagoas. Foram coletadas 32 amostras, realizando checklist higiênico-sanitário, análises de coliformes, Salmonella spp., Staphylococcus aureus e Cromatografia Gasosa com Espectrômetro de Massas (GC-MS) para pesquisa de agrotóxicos; utilizando-se duas metodologias para estudos parasitológicos. Foram analisadas 32 amostras, com nível de adequação sanitária de 45% e 38% para feiras (agroecológicas e convencionais) respectivamente, sendo três amostras no total (9,4%) adequadas a padrão microbiológico segundo RDC n° 12//2001; Dentre as 23 amostras positivas para parasitos, 69,5% teve origem em amostras de feiras convencionais, e 53% de todas as amostras positivas apresentaram Entamoeba coli como principal contaminante, juntamente, não foi detectado traços de deltametrina, porem foi visualizado em duas amostras, pico de retenção para padrão de difenoconazol. Concluindo-se que as feiras representam um ambiente adequado para patógenos humanos e indicadores, necessitando de uma maior higienização e treinamento dos comerciantes e consumidores de hortaliças do estado de Alagoas, principalmente em feiras convencionais, que apresentaram índices microbiológicos e parasitológicos mais críticos em relação a feiras com produtos agroecológicos; mas, a presença de difenoconazole em duas amostras de feiras agroecológicas sugerem contaminação acidental ou uso indiscriminado deste químico em produção da Lactuca sativa L., todavia os produtos de origem agroecológica representam uma melhor escolha para o consumidor.


Assuntos
Animais , Agroquímicos/análise , Lactuca/microbiologia , Lactuca/parasitologia , Coliformes , Salmonella , Staphylococcus aureus , Cromatografia Gasosa-Espectrometria de Massas
10.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468681

RESUMO

Abstract Agroecological production represents a new reality in vegetable farming. Thus, the study aimed to search for the presence of pesticides in agroecological samples and microbiological and parasitological contamination in Lactuca sativa L. of agroecological and conventional fairs in Alagoas. Thirty-two samples were collected, a hygienic-sanitary checklist was performed, along with coliform, Salmonella spp., Staphylococcus aureus research and Gas Chromatography with Mass Spectrometer (GC-MS) for pesticide research; using two methodologies for parasitological studies. Thirty-two samples were analyzed, with a sanitary adequacy level at 45% and 38% for fairs (agroecological and conventional) respectively, with three samples (9.4%) in total, being adequate to the microbiological pattern according to RDC no. 12/2001. Among the 23 samples which were tested positive for parasites, 69.5% originated from samples extracted at conventional fairs, and 53% of every positive samples presented Entamoeba coli as the main contaminant. All together, no traces of deltamethrin were detected, but in two of the samples a peak retention for diphenoconazole was detected. In conclusion, the fairs represent an adequate environment for human pathogens and indicators. Therefore greater hygiene training of vegetable traders and consumers in the state of Alagoas is required, especially in conventional fairs, which presented more critical microbiological and parasitological indexes comparing to fairs with agroecological products; however, the presence of difenoconazole in two samples of agricultural fairs suggests accidental contamination or indiscriminate use of this chemical in the production of Lactuca sativa, however, products with agroecological origin represents a better choice for the consumers.


Resumo A produção agroecológica representa uma nova realidade no cultivo das hortaliças. Assim, o estudo teve como objetivo verificar a presença de agrotóxicos em amostras agroecológicas e analisar a contaminação microbiológico e parasitológico em Lactuca sativa L. de feiras agroecológicas e convencionais de Alagoas. Foram coletadas 32 amostras, realizando checklist higiênico-sanitário, análises de coliformes, Salmonella spp., Staphylococcus aureus e Cromatografia Gasosa com Espectrômetro de Massas (GC-MS) para pesquisa de agrotóxicos; utilizando-se duas metodologias para estudos parasitológicos. Foram analisadas 32 amostras, com nível de adequação sanitária de 45% e 38% para feiras (agroecológicas e convencionais) respectivamente, sendo três amostras no total (9,4%) adequadas a padrão microbiológico segundo RDC n° 12//2001; Dentre as 23 amostras positivas para parasitos, 69,5% teve origem em amostras de feiras convencionais, e 53% de todas as amostras positivas apresentaram Entamoeba coli como principal contaminante, juntamente, não foi detectado traços de deltametrina, porem foi visualizado em duas amostras, pico de retenção para padrão de difenoconazol. Concluindo-se que as feiras representam um ambiente adequado para patógenos humanos e indicadores, necessitando de uma maior higienização e treinamento dos comerciantes e consumidores de hortaliças do estado de Alagoas, principalmente em feiras convencionais, que apresentaram índices microbiológicos e parasitológicos mais críticos em relação a feiras com produtos agroecológicos; mas, a presença de difenoconazole em duas amostras de feiras agroecológicas sugerem contaminação acidental ou uso indiscriminado deste químico em produção da Lactuca sativa L., todavia os produtos de origem agroecológica representam uma melhor escolha para o consumidor.

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