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1.
Phys Rev Lett ; 131(14): 141801, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37862636

RESUMO

We describe a first measurement of the radiation from a ^{178m}Hf sample to search for dark matter. The γ flux from this sample, possessed by Los Alamos National Laboratory nuclear chemistry, was measured with a Ge detector at a distance of 1.2 m due to its high activity. We search for γ's that cannot arise from the radioactive decay of ^{178m}Hf but might arise from the production of a nuclear state due to the inelastic scattering with dark matter. The limits obtained on this γ flux are then translated into constraints on the parameter space of inelastic dark matter. Finally, we describe the potential reach of future studies with ^{178m}Hf.

2.
Phys Rev Lett ; 129(2): 021801, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35867467

RESUMO

We report the first results of a search for leptophobic dark matter (DM) from the Coherent-CAPTAIN-Mills (CCM) liquid argon (LAr) detector. An engineering run with 120 photomultiplier tubes (PMTs) and 17.9×10^{20} protons on target (POT) was performed in fall 2019 to study the characteristics of the CCM detector. The operation of this 10-ton detector was strictly light based with a threshold of 50 keV and used coherent elastic scattering off argon nuclei to detect DM. Despite only 1.5 months of accumulated luminosity, contaminated LAr, and nonoptimized shielding, CCM's first engineering run has already achieved sensitivity to previously unexplored parameter space of light dark matter models with a baryonic vector portal. With an expected background of 115 005 events, we observe 115 005+16.5 events which is compatible with background expectations. For a benchmark mediator-to-DM mass ratio of m_{V_{B}}/m_{χ}=2.1, DM masses within the range 9 MeV≲m_{χ}≲50 MeV are excluded at 90% C. L. in the leptophobic model after applying the Feldman-Cousins test statistic. CCM's upgraded run with 200 PMTs, filtered LAr, improved shielding, and 10 times more POT will be able to exclude the remaining thermal relic density parameter space of this model, as well as probe new parameter space of other leptophobic DM models.

3.
Braz. j. biol ; 82: 1-10, 2022. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468477

RESUMO

The secondary metabolism products of plants have influenced great economic interest, given their chemical diversity and biological activities. Because of this, this study evaluates the phytochemical composition, antimicrobial activity, insecticidal, and antioxidant activity of plant extracts and oil of Myrcia oblongata. Saponins, steroids, triterpenoids, tannins, and flavonoids were detected. The extracts showed antimicrobial capacity on the tested microorganisms, except for the methanolic extract, which showed no activity for P. mirabilis and S. enteritidis. Regarding the analysis of antioxidant compounds, the hexanic, ethyl acetate and acetone extracts showed higher antioxidant activities and also higher insecticidal performance on Alphitobius diaperinus larvae, resulting in 80% adult mortality. The results reported here show that there may be a relationship between antioxidant potential and the insecticidal effect of Myrcia oblongata DC. The components present in both the extract and the oil can be used as natural alternative to synthetic compounds in the biological control of parasites and pathogenic microorganisms.


Os produtos do metabolismo secundário das plantas têm despertado grande interesse econômico, dada sua diversidade química e atividades biológicas. Neste sentido, o estudo objetivou avaliar a composição fitoquímica, atividade antimicrobiana, inseticida e antioxidante dos extratos vegetais e óleo de Myrcia oblongata. Foram detectados a presença de saponinas, esteróides, triterpenóides, taninos e flavonóides. Os extratos apresentaram capacidade antimicrobiana sobre os microrganismos testados, exceto o extrato metanólico que não demonstrou atividade para P. mirabilis e S. Enteritidis. Quanto a análise de compostos antioxidantes observou-se que os extratos hexânico, acetato de etila e acetona apresentaram maiores atividades antioxidantes e também maior performance inseticida sobre a larva Alphitobius diaperinus e exibindo mortalidade de 80% na fase adulta. Os resultados aqui reportados mostram que pode haver uma relação entre potencial antioxidante e efeito inseticida do óleo de Myrcia oblongata; os componentes presentes tanto no extrato como o oléo podem ser utilizados como alternativa natural aos compostos sintéticos no controle biológico de parasitas e microrganismos patogênicos.


Assuntos
Animais , Antioxidantes/análise , Besouros , Fitoterapia , Inseticidas/análise , Myrtaceae/microbiologia , Myrtaceae/química , Salmonella
4.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468664

RESUMO

Abstract The secondary metabolism products of plants have influenced great economic interest, given their chemical diversity and biological activities. Because of this, this study evaluates the phytochemical composition, antimicrobial activity, insecticidal, and antioxidant activity of plant extracts and oil of Myrcia oblongata. Saponins, steroids, triterpenoids, tannins, and flavonoids were detected. The extracts showed antimicrobial capacity on the tested microorganisms, except for the methanolic extract, which showed no activity for P. mirabilis and S. enteritidis. Regarding the analysis of antioxidant compounds, the hexanic, ethyl acetate and acetone extracts showed higher antioxidant activities and also higher insecticidal performance on Alphitobius diaperinus larvae, resulting in 80% adult mortality. The results reported here show that there may be a relationship between antioxidant potential and the insecticidal effect of Myrcia oblongata DC. The components present in both the extract and the oil can be used as natural alternative to synthetic compounds in the biological control of parasites and pathogenic microorganisms.


Resumo Os produtos do metabolismo secundário das plantas têm despertado grande interesse econômico, dada sua diversidade química e atividades biológicas. Neste sentido, o estudo objetivou avaliar a composição fitoquímica, atividade antimicrobiana, inseticida e antioxidante dos extratos vegetais e óleo de Myrcia oblongata. Foram detectados a presença de saponinas, esteróides, triterpenóides, taninos e flavonóides. Os extratos apresentaram capacidade antimicrobiana sobre os microrganismos testados, exceto o extrato metanólico que não demonstrou atividade para P. mirabilis e S. Enteritidis. Quanto a análise de compostos antioxidantes observou-se que os extratos hexânico, acetato de etila e acetona apresentaram maiores atividades antioxidantes e também maior performance inseticida sobre a larva Alphitobius diaperinus e exibindo mortalidade de 80% na fase adulta. Os resultados aqui reportados mostram que pode haver uma relação entre potencial antioxidante e efeito inseticida do óleo de Myrcia oblongata; os componentes presentes tanto no extrato como o oléo podem ser utilizados como alternativa natural aos compostos sintéticos no controle biológico de parasitas e microrganismos patogênicos.

5.
Braz. j. biol ; 82: e233425, 2022. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1249266

RESUMO

The secondary metabolism products of plants have influenced great economic interest, given their chemical diversity and biological activities. Because of this, this study evaluates the phytochemical composition, antimicrobial activity, insecticidal, and antioxidant activity of plant extracts and oil of Myrcia oblongata. Saponins, steroids, triterpenoids, tannins, and flavonoids were detected. The extracts showed antimicrobial capacity on the tested microorganisms, except for the methanolic extract, which showed no activity for P. mirabilis and S. enteritidis. Regarding the analysis of antioxidant compounds, the hexanic, ethyl acetate and acetone extracts showed higher antioxidant activities and also higher insecticidal performance on Alphitobius diaperinus larvae, resulting in 80% adult mortality. The results reported here show that there may be a relationship between antioxidant potential and the insecticidal effect of Myrcia oblongata DC. The components present in both the extract and the oil can be used as natural alternative to synthetic compounds in the biological control of parasites and pathogenic microorganisms.


Os produtos do metabolismo secundário das plantas têm despertado grande interesse econômico, dada sua diversidade química e atividades biológicas. Neste sentido, o estudo objetivou avaliar a composição fitoquímica, atividade antimicrobiana, inseticida e antioxidante dos extratos vegetais e óleo de Myrcia oblongata. Foram detectados a presença de saponinas, esteróides, triterpenóides, taninos e flavonóides. Os extratos apresentaram capacidade antimicrobiana sobre os microrganismos testados, exceto o extrato metanólico que não demonstrou atividade para P. mirabilis e S. Enteritidis. Quanto a análise de compostos antioxidantes observou-se que os extratos hexânico, acetato de etila e acetona apresentaram maiores atividades antioxidantes e também maior performance inseticida sobre a larva Alphitobius diaperinus e exibindo mortalidade de 80% na fase adulta. Os resultados aqui reportados mostram que pode haver uma relação entre potencial antioxidante e efeito inseticida do óleo de Myrcia oblongata; os componentes presentes tanto no extrato como o oléo podem ser utilizados como alternativa natural aos compostos sintéticos no controle biológico de parasitas e microrganismos patogênicos.


Assuntos
Óleos Voláteis , Inseticidas , Anti-Infecciosos , Bactérias , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Antioxidantes/farmacologia
6.
Braz J Biol ; 82: e233425, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34105655

RESUMO

The secondary metabolism products of plants have influenced great economic interest, given their chemical diversity and biological activities. Because of this, this study evaluates the phytochemical composition, antimicrobial activity, insecticidal, and antioxidant activity of plant extracts and oil of Myrcia oblongata. Saponins, steroids, triterpenoids, tannins, and flavonoids were detected. The extracts showed antimicrobial capacity on the tested microorganisms, except for the methanolic extract, which showed no activity for P. mirabilis and S. enteritidis. Regarding the analysis of antioxidant compounds, the hexanic, ethyl acetate and acetone extracts showed higher antioxidant activities and also higher insecticidal performance on Alphitobius diaperinus larvae, resulting in 80% adult mortality. The results reported here show that there may be a relationship between antioxidant potential and the insecticidal effect of Myrcia oblongata DC. The components present in both the extract and the oil can be used as natural alternative to synthetic compounds in the biological control of parasites and pathogenic microorganisms.


Assuntos
Anti-Infecciosos , Inseticidas , Óleos Voláteis , Antioxidantes/farmacologia , Bactérias , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia
7.
Nutr Neurosci ; 24(11): 907-918, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31757196

RESUMO

Purpose: Dysregulation of glutamatergic neurotransmission (GN) is linked to sympathetic-respiratory overactivity and hypertension. We investigated whether maternal protein restriction is able to alter GN into the nucleus of the solitary tract (NTS) in adult offspring.Methods: Wistar rat dams were fed with control (NP; 17% protein) or low-protein (LP; 8% protein) diet during pregnancy and lactation, and their offspring were evaluated at 70-90d old. Direct measurements of mean arterial pressure (MAP), heart rate (HR), respiratory frequency (RF) and respiratory (RV) and cardiac (CV) variabilities were assessed in consciousness. The evaluation of GN into NTS over cardiovascular system were assessed by microinjections of unilateral glutamate (L-glu 0.5 nmol/100nL) and bilateral kynurenic acid (Kyn 2.5 nmol/50nL). The NP and LP groups were compared using unpaired Student's t-test where p < 0.05 was considered significant.Results: The LP exhibited higher MAP at rest (p = 0.03) and after L-glu microinjection (p = 0.04), as well as an increase over HR after Kyn microinjection when compared to the NP (p = 0.049). In the RV, the LP group showed an increase of the component-standard deviation 1 (p = 0.037) at rest. In the CV, the LP presented an increase of the low frequency (LF) component of the pulse interval (PI) (p = 0.034), a decrease of high frequency (HF) of the PI (p = 0.034), beyond an increased LF/HF ratio of the PI (p = 0.027) when compared to the NP. The kynurenic acid microinjection did not produce changes in RV or CV (p > 0.05).Conclusions: Altered GN into the NTS may contribute to augmented blood pressure in protein-restricted offspring.


Assuntos
Sistema Cardiovascular , Ácido Glutâmico , Animais , Pressão Sanguínea , Estado de Consciência , Dieta com Restrição de Proteínas , Feminino , Ácido Glutâmico/metabolismo , Frequência Cardíaca/fisiologia , Humanos , Microinjeções , Gravidez , Ratos , Ratos Wistar , Núcleo Solitário/metabolismo
8.
J Econ Entomol ; 109(2): 649-59, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26791817

RESUMO

This study was performed to investigate the activity of 19 dichloromethane-soluble fractions obtained from the methanolic extracts of 10 Annonaceae species against the fall armyworm, Spodoptera frugiperda (J. E. Smith). The stem bark of Duguetia lanceolata A. St.-Hil. showed the highest insecticidal activity, with a median lethal time (LT50) of 61.4 h and a median lethal concentration (LC50) of 946.5 µg/ml of diet. The dichloromethane-soluble fractions from six D. lanceolata specimens were subjected to evaluation of their activities against S. frugiperda and metabolomic analysis using hydrogen (1H) nuclear magnetic resonance (NMR) spectroscopy. Although all of the samples affected S. frugiperda mortality, their insecticidal activities varied according to the sample used in the experiments. Using partial least squares regression of the results, the D. lanceolata specimens were grouped according to their metabolite profile and insecticidal activity. A detailed analysis via uni- and bidimensional NMR spectroscopy showed that the peaks in the 1H NMR spectra associated with increased insecticidal activity could be attributed to 2,4,5-trimethoxystyrene, which suggests that this substance is involved in the insecticidal activity of the stem bark fraction of D. lanceolata.


Assuntos
Annonaceae/química , Controle de Insetos , Inseticidas/análise , Spodoptera , Animais , Annonaceae/metabolismo , Espectroscopia de Ressonância Magnética , Testes de Toxicidade
10.
Rev. bras. plantas med ; 15(3): 352-362, 2013. tab
Artigo em Inglês | LILACS | ID: lil-684151

RESUMO

Aiming to contribute to the development of alternative control methods of the coffee leaf miner, Leucoptera coffeella (Guérin-Mèneville & Perrottet, 1842) (Lepidoptera: Lyonetiidae), a search for plants able to produce active substances against this insect was carried out, with species collected during different periods of time in the Alto Rio Grande region, (Lavras, Minas Gerais, Brazil). Coffee leaves containing L. coffeella mines were joined with 106 extracts from 77 plant species and, after 48 hours, the dead and alive caterpillars were counted. The extracts from Achillea millefolium, Citrus limon, Glechoma hederacea, Malva sylvestris, Mangifera indica, Mentha spicata, Mirabilis jalapa, Musa sapientum, Ocimum basiculum, Petiveria alliaceae, Porophyllum ruderale, Psidium guajava, Rosmarinus officinalis, Roupala montana, Sambucus nigra and Tropaeolum majus showed the highest mortality rates.


Visando contribuir para o desenvolvimento de métodos alternativos de controle do bicho-mineiro-do-cafeeiro, Leucoptera coffeella (Lepidoptera: Lyonetiidae), buscou-se selecionar plantas coletadas em diferentes épocas na região do Alto Rio Grande, (Lavras, Minas Gerais, Brasil) que contenham substâncias ativas contra este inseto. Folhas de cafeeiro com minas intactas de L. coffeella foram colocadas em contato com 106 extratos provenientes de 78 espécies vegetais e, após 48 horas, contaram-se as lagartas vivas e mortas. Os extratos de Achillea millefolium, Citrus limon, Glechoma hederacea, Malva sylvestris, Mangifera indica, Mentha spicata, Mirabilis jalapa, Musa sapientum, Ocimum basiculum, Petiveria alliaceae, Porophyllum ruderale, Psidium guajava, Rosmarinus officinalis, Roupala montana, Sambucus nigra e Tropaeolum majus, provocaram os maiores índices de mortalidade.


Assuntos
Produtos Biológicos/efeitos adversos , Lepidópteros/imunologia , Extratos Vegetais/análise
11.
Neotrop Entomol ; 41(6): 503-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23949676

RESUMO

Plant extracts represent a great source of molecules, with insecticidal activity, which are used for pest control in several crop production systems. This work aimed to evaluate the toxicity of an aqueous extract of leaves of castor bean against larvae of Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) in search for different classes of molecules with insecticidal activities by using in vitro assays. The effects of the castor bean leaf extract on the food utilization, development, and survival of S. frugiperda larvae was evaluated by feeding the larvae an artificial diet supplemented with different concentrations of the extract (0%, 1%, 2.5%, 5%, and 10% w/v). The effects observed were dose-dependent, and the highest concentration evaluated (10% w/v) was the one the most affected food utilization by altering the nutritional indices, as well as larval weight gain, development time, and survivorship. In vitro assays to detect saponins, lectins, and trypsin inhibitors in the castor bean leaf extract were performed, but only trypsin inhibitors were detected. No preference for the diet source was detected in S. frugiperda by feeding the larvae in choice experiments with diets containing different concentrations of the castor bean extract tested. The data obtained indicate the existence of a potential molecule in the tested extract of castor bean to be used as an alternative insecticide to be integrated in the management of S. frugiperda.


Assuntos
Inseticidas , Lepidópteros/efeitos dos fármacos , Lepidópteros/fisiologia , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Ricinus communis , Animais , Folhas de Planta
12.
Neotrop Entomol ; 40(1): 123-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21437494

RESUMO

We evaluated the effects of crude extracts from the plantain Plantago lanceolata and the bitter gourd Momordica charantia on the oviposition preference and development of the coffee leaf miner Leucoptera coffeella Guérin-Mèneville & Perrottet under laboratory and/or greenhouse conditions. The ovicidal effects of these extracts were also studied in a greenhouse. Plantago lanceolata and M. charantia extracts also underwent fractionation directed by oviposition tests with the coffee leaf miner. The extracts of both plants reduced L. coffeella oviposition and egg hatching, apparently as a result of action of plant metabolites on the embryo. Adults originating from eggs treated with the extracts exhibited similar survival rates, but a higher female/male ratio. Fecundity was reduced for females obtained from eggs treated with the M. charantia extract. Partial chemical analysis indicated that both extracts produced polar fractions that reduced the oviposition of L. coffeella on coffee leaves under laboratory conditions. The extracts of P. lanceolata and M. charantia have potential for use in the development of new products to control the coffee leaf miner.


Assuntos
Lepidópteros/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantago , Animais , Lepidópteros/anatomia & histologia , Lepidópteros/crescimento & desenvolvimento , Oviposição/efeitos dos fármacos , Controle Biológico de Vetores
13.
Braz. j. phys. ther. (Impr.) ; 12(5): 366-372, set.-out. 2008. ilus, tab, graf
Artigo em Português | LILACS | ID: lil-499905

RESUMO

CONTEXTUALIZAÇÃO: O estudo do comportamento das propriedades mecânicas do tendão in vivo pode trazer avanços na avaliação do impacto de programas de intervenção para flexibilidade e força, nas áreas clínica e desportiva. OBJETIVO: O objetivo deste trabalho foi quantificar a deformação (strain) e a frouxidão (slackness) relativas do tendão calcanear, durante mobilização passiva para quatro ângulos articulares do tornozelo e dois do joelho. MATERIAIS E MÉTODOS: O deslocamento da junção miotendínea foi quantificado através de imagens ultra-sonográficas capturadas durante a mobilização passiva do tornozelo, com o auxílio de um eletrogoniômetro e um eletromiógrafo, para garantir as angulações requeridas e a inatividade muscular, respectivamente. RESULTADOS: Os valores de deformação relativa encontrados variaram de 4,28±2,37 a -0,94±1,58 por cento para o joelho estendido e de 2,38±1,63 a -2,32±2,16 por cento para o joelho fletido. CONCLUSÕES: Os valores encontrados ratificam os da literatura, demonstrando a participação do tendão calcanear na variação do comprimento da unidade músculo-tendão, durante movimentação passiva. Estes resultados sugerem que as propriedades mecânicas dos tecidos tendinosos afetam a relação entre o comprimento das fibras e o ângulo articular, até mesmo nesse tipo de movimento.


BACKGROUND: In vivo study of the mechanical behavior of tendons may bring advances in evaluating the impact of intervention programs for flexibility and strength, in clinical practice and sports. OBJECTIVE: The aim of this study was to quantify the relative strain and slackness of achilles tendons during passive mobilization, for four ankle joint angles and two knee angles. METHODS: The displacement of the muscle-tendon junction was quantified by means of ultrasound images acquired during passive ankle mobilization, with the aid of an electrogoniometer and an electromyograph to ensure the achievement of the required angles and muscle inactivity, respectively. RESULTS: The strain values ranged from 4.28 percent±2.37 to -0.94 percent±1.58 for the fully extended knee, and from 2.38 percent±1.63 to -2.32 percent±2.16 percent for the flexed knee. CONCLUSIONS: The values found in this study confirm those in the literature and demonstrate how the Achilles tendon participates in length changes in the muscle-tendon unit during passive movement. These results suggest that the mechanical properties of tendinous tissues affect the relationship between the length of muscle fibers and the joint angle, even during this type of movement.

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