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371.
Norenberg João Pedro Cunha Americo da Silva Samuel Varoto Paulo Sergio 《Nonlinear dynamics》2022,109(2):443-458
Nonlinear Dynamics - Parametric variability is inevitable in actual energy harvesters. It can significantly affect crucial aspects of the system performance, especially in harvesting systems that... 相似文献
372.
P. Abreu S. Andringa P. Assis A. Blanco V. Barbosa Martins P. Brogueira N. Carolino L. Cazon M. Cerda G. Cernicchiaro R. Colalillo R. Conceição O. Cunha R. M. de Almeida V. de Souza F. Diogo C. Dobrigkeit J. Espadanal C. Espirito-Santo M. Ferreira P. Ferreira P. Fonte U. Giaccari P. Gonçalves F. Guarino O. C. Lippmann L. Lopes R. Luz D. Maurizio F. Marujo P. Mazur L. Mendes A. Pereira Mario Pimenta R. R. Prado J. R̆ídký R. Sarmento C. Scarso R. Shellard J. Souza B. Tomé P. Trávníc̆ek J. Vícha H. Wolters E. Zas 《The European Physical Journal C - Particles and Fields》2018,78(4):333
A new concept for the direct measurement of muons in air showers is presented. The concept is based on resistive plate chambers (RPCs), which can directly measure muons with very good space and time resolution. The muon detector is shielded by placing it under another detector able to absorb and measure the electromagnetic component of the showers such as a water-Cherenkov detector, commonly used in air shower arrays. The combination of the two detectors in a single, compact detector unit provides a unique measurement that opens rich possibilities in the study of air showers. 相似文献
373.
Ricardo Ferreira‐Nunes Larissa A. Ferreira Tais Gratieri Marcilio Cunha‐Filho Guilherme M. Gelfuso 《Biomedical chromatography : BMC》2019,33(11)
A simple, stability‐indicating, chromatographic method of quantifying spironolactone (SPI) and its metabolite, canrenone (CAN), in the presence of excipients typical in dermatological formulations and skin matrices in studies of passive and iontophoretic permeation was proposed and validated here. SPI and CAN were separated using a reversed‐phase column with a mobile phase of methanol–water (60:40, v/v) at a flow rate of 1.0 mL/min. Data were collected with a UV detector at 238 and 280 nm, with retention times of 6.2 and 7.9 min for SPI and CAN, respectively. The method was precise, accurate and linear (r2 > 0.99) in a concentration range of 1–30 μg/mL, and recovery rates of SPI and CAN from the different skin layers exceeded 85%. The method was not only sensitive (LOD of 0.05 and 0.375 μg/mL and LOQ of 0.157 and 1.139 μg/mL for SPI and CAN, respectively) but also selective against skin matrices and highly representative components of topical formulations. The method moreover demonstrated SPI's degradation in iontophoresis by applying Pt–AgCl electrodes and its continued drug stability using Ag–AgCl electrodes. Altogether, the method proved valuable for quantifying SPI and CAN and may be applied in developing and controlling the quality of dermatological products. 相似文献
374.
Amorim Daniel Roger Bezerra Bellucci Felipe Silva Job Aldo Eloizo Guimarães Iran da Silva da Cunha Helder Nunes 《Journal of Thermal Analysis and Calorimetry》2019,136(4):1615-1629
Journal of Thermal Analysis and Calorimetry - The application of cashew gum, in particular the one which is abundant in northeastern Brazil, remains limited to the foods and pharmaceutics industry.... 相似文献
375.
376.
Carlos Vinicius Barros Oliveira Patric Anderson Gomes da Silva Saulo Relison Tintino Cathia Cecília Coronel Maria Celeste Vega Gomez Mírian Roln Francisco Assis Bezerra da Cunha Maria Flaviana Bezerra Morais-Braga Henrique Douglas Melo Coutinho Abolghasem Siyadatpanah Polrat Wilairatana Jean Paul Kamdem Luiz Marivando Barros Antonia Eliene Duarte Pedro Silvino Pereira 《Molecules (Basel, Switzerland)》2022,27(7)
Weeds are an important source of natural products; with promising biological activity. This study investigated the anti-kinetoplastida potential (in vitro) to evaluate the cytotoxicity (in vitro) and antioxidant capacity of the essential oil of Rhaphiodon echinus (EORe), which is an infesting plant species. The essential oil was analyzed by GC/MS. The antioxidant capacity was evaluated by reduction of the DPPH radical and Fe3+ ion. The clone Trypanosoma cruzi CL-B5 was used to search for anti-epimastigote activity. Antileishmanial activity was determined using promastigotes of Leishmania braziliensis (MHOM/CW/88/UA301). NCTC 929 fibroblasts were used for the cytotoxicity test. The results showed that the main constituent of the essential oil was γ-elemene. No relevant effect was observed concerning the ability to reduce the DPPH radical; only at the concentration of 480 μg/mL did the essential oil demonstrate a high reduction of Fe3+ power. The oil was active against L. brasiliensis promastigotes; but not against the epimastigote form of T. cruzi. Cytotoxicity for mammalian cells was low at the active concentration capable of killing more than 70% of promastigote forms. The results revealed that the essential oil of R. echinus showed activity against L. brasiliensis; positioning itself as a promising agent for antileishmanial therapies. 相似文献
377.
Matilde S. Rodrigues Samira G. Ferreira Csar Quiroz Christopher J. Earley Diego García-Borreguero Rodrigo A. Cunha Francisco Ciruela Attila Kfalvi Sergi Ferr 《Molecules (Basel, Switzerland)》2022,27(5)
Brain iron deficiency (BID) constitutes a primary pathophysiological mechanism in restless legs syndrome (RLS). BID in rodents has been widely used as an animal model of RLS, since it recapitulates key neurochemical changes reported in RLS patients and shows an RLS-like behavioral phenotype. Previous studies with the BID-rodent model of RLS demonstrated increased sensitivity of cortical pyramidal cells to release glutamate from their striatal nerve terminals driving striatal circuits, a correlative finding of the cortical motor hyperexcitability of RLS patients. It was also found that BID in rodents leads to changes in the adenosinergic system, a downregulation of the inhibitory adenosine A1 receptors (A1Rs) and upregulation of the excitatory adenosine A2A receptors (A2ARs). It was then hypothesized, but not proven, that the BID-induced increased sensitivity of cortico-striatal glutamatergic terminals could be induced by a change in A1R/A2AR stoichiometry in favor of A2ARs. Here, we used a newly developed FACS-based synaptometric analysis to compare the relative abundance on A1Rs and A2ARs in cortico-striatal and thalamo-striatal glutamatergic terminals (labeled with vesicular glutamate transporters VGLUT1 and VGLUT2, respectively) of control and BID rats. It could be demonstrated that BID (determined by measuring transferrin receptor density in the brain) is associated with a selective decrease in the A1R/A2AR ratio in VGLUT1 positive-striatal terminals. 相似文献
378.
379.
This work evaluates the mechanical performance of injection-molded starch-based copolymers, 60/40 (mol/mol) starch/poly(ethylene vinyl alcohol), and the possibility of improving material properties through deliberately induced anisotropy during processing. Different types of samples were produced by conventional and shear-controlled injection molding (Scorim) and tested under tensile and impact loading. The behavior of three distinct grades is discussed in terms of the respective fracture morphology (evaluated by scanning electron microscopy). A comparison is made between the behavior of conventional and Scorim samples. The results show that the mechanical properties of the materials used were significantly improved by the employment of the Scorim process. The stiffness values of the conventional moldings were doubled, without reducing the ductility of the polymer. The impact data showed a material sensitivity, and consequent loss of properties, to the localized shear imposed to the melt during processing. This situation is attributed to very narrow mold gates (in the case of pingated systems) and leads to much reduced impact performance. 相似文献
380.