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101.
Numerical Algorithms - The motivation of this work stems from the numerical approximation of bounded functions by polynomials satisfying the same bounds. The present contribution makes use of the... 相似文献
102.
Douglas G. Macharet Armando Alves Neto Vila F. da Camara Neto Mario F. M. Campos 《Journal of Heuristics》2018,24(1):83-109
In this paper we address the problem of planning optimized routes among dynamically selected target regions for vehicles with a turning radius motion constraint, hereinafter called dynamic Dubins traveling salesman problem with neighborhoods (DDTSPN). Initially, we present a heuristic to solve a simpler version of this problem, called off-line step, where only previously given targets are concerned. We further extend this approach for the more complex case of dynamic scenarios, called on-line step, addressing the inclusion of new targets during the execution of the initial route, whilst minimizing the impact on the total traveled distance. Formal analyzes of our techniques are provided, presenting upper bounds for the total length of the final tour. Results with statistical investigation over a large number of trials in a simulated environment are also provided. Finally, to demonstrate the applicability of our technique in solving the DDTSPN at real-world scenarios, we also report on results of an experiment performed with a real car-like robot. 相似文献
103.
Ana Santos‐Coquillat Enrique Martínez‐Campos Nelson Vargas‐Alfredo Raúl Arrabal Juan Rodríguez‐Hernndez Endzhe Matykina 《Macromolecular bioscience》2019,19(10)
Magnesium‐based implants present several advantages for clinical applications, in particular due to their biocompatibility and degradability. However, degradation products can affect negatively the cell activity. In this work, a combined coating strategy to control the implant degradation and cell regulation processes is evaluated, including plasma electrolytic oxidation (PEO) that produces a 13 µm‐thick Ca, P, and Si containing ceramic coating with surface porosity, and breath figures (BF) approach that produces a porous polymeric poly(ε‐caprolactone) surface. The degradation of PCL‐PEO‐coated Mg hierarchical scaffold can be tailored to promote cell adhesion and proliferation into the porous structure. As a result, cell culture can colonize the inner PEO‐ceramic coating structure where higher amount of bioelements are present. The Mg/PEO/PCL/BF scaffolds exhibit equally good or better premyoblast cell adhesion and proliferation compared with Ti CP control. The biological behavior of this new hierarchical functionalized scaffold can improve the implantation success in bone and cardiovascular clinical applications. 相似文献
104.
P. Barahona O. Pea A.B. Antunes C. Campos G. Pecchi Y. Moreno C. Moure V. Gil 《Journal of magnetism and magnetic materials》2008,320(14):e61-e64
Partial substitution of manganese by cobalt in rare-earth perovskites REMnO3 leads to unusual magnetic phenomena because of the simultaneous presence of Mn3+, Mn4+, Co2+ and Co3+ species. The magnetic nature of the RE cation plays a fundamental role in the magnetic properties. We present herein two specific families: for RE=La the magnetic behavior of the |Co+Mn| network is observed, while for Gd its strong magnetic moment interacts with the transition metals, leading to a spin reversal state. Magnetic interactions are maximized at x=0.50, as if two regimes exist: for x<0.5 Co substitutes Mn in the REMnO3 manganite, and for x>0.5 Mn substitutes Co in the RECoO3 cobaltite. 相似文献
105.
In this work we will present theoretical arguments that explain why the nematic phase exhibits a universal behavior encompassing its entire range. By considering that the physical properties of the nematic molecules can be written as a product of two distinct terms, being the first a compound dependent term and the another a function characterizing the nematic phase, it will be shown that it is possible to remove from the experimental data the particularities characterizing an specific compound and a universal behavior is obtained. Furthermore, it will be shown that these universalities should be a direct consequence of a more fundamental universality, the universal geometrical shape of the nematic molecules. 相似文献
106.
Molina FD Bertollo EM Assis CM Falleiros LR Campos SG Maniglia JV Taboga SR 《Micron (Oxford, England : 1993)》2008,39(7):910-914
Squamous cell carcinoma of the tongue is one of the most common head and neck cancer. Treatment in the early stages is still controversial. This study aims to correlate the apoptosis rate of primary tongue cancer with cervical node metastasis, found in the histopathological studies of specimens obtained from neck dissections or during clinical follow-up. Twenty patients, 65% males, mean age 64.5 years, without clinical evidence of cervical metastasis was included. Eighty-five percent were smokers and 40% were alcohol abusers. Mann-Whitney test was used for statistical analysis (p=0.05). Five patients with clinically occult cervical metastases had metastasis in the histopathological specimens (25%) occult metastasis. The mean apoptosis rate in patients without cervical metastasis was 9.43%. Twenty-five percent of the patients had occult cervical metastasis. High apoptosis rate in tongue cancer, even in the absence of palpable neck nodes, correlates with the presence of occult metastasis. 相似文献
107.
J.C. de Lima A.R. Jerônimo A. Gomez S.M. Souza D.M. Trichês C.E.M. Campos T.A. Grandi S. Kycia 《Journal of Non》2008,354(40-41):4598-4602
The atomic structure of an amorphous Si24Nb76 alloy produced by mechanical alloying was investigated by using one X-ray total structure factor S(K) as input data for reverse Monte Carlo (RMC) simulations. The partial SSi–Si(K), SSi–Nb(K), SNb–Nb(K) structure factors and GSi–Si(r), GSi–Nb(r), GNb–Nb(r) pair probability functions were obtained from the RMC simulations. The structural parameters (interatomic distances and co-ordination numbers) for the first neighbors were extracted and compared with those found in the Nb3Si compound. It was observed some resemblance between these phases. 相似文献
108.
Hugo M. Campos Vladislav V. Kravchenko 《Mathematical Methods in the Applied Sciences》2020,43(16):9448-9454
The paper extends some well-known results for analytic functions onto solutions of the Vekua equation regarding the existence and construction of the Bergman kernel and of the corresponding Bergman projection operator. 相似文献
109.
Carla Maria Mariano Fernandez Maurício Ferreira da Rosa Ana Claudia Aparecida Mariano Fernandez Wanessa de Campos Bortolucci Fabiana Borges Padilha Ferreira Giani Andrea Linde 《Natural product research》2020,34(5):731-735
AbstractThis study, was to evaluate the acaricidal effect of the essential oil (EO) and fractions (FR) obtained from Laurus nobilis leaves on Rhipicephalus (Boophilus) microplus. Eight fractions were obtained, however FR1: sabinene (37.83%), β-pinene (13.50%), 1,8-cineole (12.66%), α-pinene (12.56%) and FR8: α-terpineol (79.19%) were highlighted as to the larvicidal potential when submitted by Larval Packet Test. The EO was tested by the Adult Immersion Test, at concentrations of 200.00; 100.00 and 50.00?µL/mL caused mortality of engorged females, egg mass reduction and hatching inhibition. Two fractions are shown to be efficient in controlling larvae FR8 (LC50?=?0.13?µL/mL, LC99?=?0.51?µL/mL) and FR1 (LC50?=?0.20?µL/mL, LC99?=?0.56?µL/mL). The fractionation of EO was determinant to elucidate which compounds were responsible for the larvicidal potential. This study opens new perspectives to direct new bioassays with the compounds obtained in the fractionation, since they present high potential on cattle tick larvae. 相似文献
110.