Blow up of solutions for a Petrovsky type equation with logarithmic nonlinearity

Jorge Ferreira,Nazli Irkil,Erhan Piskin,Carlos Raposo,Mohammad Shahrouzi 대한수학회 2022 대한수학회보 Vol.59 No.6

This paper aims to investigate the initial boundary value problem of the nonlinear viscoelastic Petrovsky type equation with nonlinear damping and logarithmic source term. We derive the blow-up results by the combination of the perturbation energy method, concavity method, and differential-integral inequality technique.

The Semicontinuous Quasi-uniformity of a Frame

Ferreira, Maria Joao,Picado, Jorge Department of Mathematics 2006 Kyungpook mathematical journal Vol.46 No.2

The semicontinuous quasi-uniformity is known to be one of the most important examples of transitive quasi-uniformities. The aim of this paper is to show that various facts in classical topology connected with the semicontinuous quasi-uniformity and semicontinuous real functions may be easily extended to pointfree topology via a construction introduced by the authors in a previous paper. Several consequences are derived.

A Method of Constructing Compatible Frame Quasi-uniformities

Maria Joao Ferreira,Jorge Picado 경북대학교 자연과학대학 수학과 2004 Kyungpook mathematical journal Vol.44 No.3

Unlike a uniformity, a quasi-uniformity is not determined by its quasi-uniform covers. However, a classical construction, due to P. Fletcher, which assigns a transitive quasi-uniformity to each family of interior-preserving open covers, allows to describe all transitive quasi-uniformities on the topological spaces in terms of those families of covers. In this paper we develop a point free generalization of this, which solves a problem posed by G. C. L. Br¨ummer, together with various examples and applications that illustrateits remarkable usefulness. By this construction, many kinds of interior-preserving open covers (e.g. locally finite, point-finite, spectrum, well-monotone) induce compatible quasi-uniformities on an arbitrary frame.

Superoscillations With Optimum Energy Concentration

Lee, Dae Gwan,Ferreira, Paulo Jorge S. G. IEEE 2014 IEEE transactions on signal processing Vol.62 No.18

<P>Oscillations of a bandlimited signal at a rate faster than the bandlimit are called “superoscillations” and have applications e.g. in superresolution and superdirectivity. The synthesis of superoscillating signals is a numerically difficult problem. Minimum energy superoscillatory signals seem attractive for applications because (i) the minimum-energy solution is unique (ii) it has the smallest energy cost (iii) it may yield a signal of the smallest possible amplitude. On the negative side, superoscillating functions of minimum-energy depend heavily on cancellation and give rise to expressions that have very large coefficients. Furthermore, these coefficients have to be found by solving equations that are very ill-conditioned. Surprisingly, we show that by dropping the minimum energy requirement practicality can be gained rather than lost. We give a method of constructing superoscillating signals that leads to coefficients and condition numbers that are smaller by several orders of magnitude than the minimum-energy solution, yet yields energies close to the minimum. In contrast with the minimum-energy method, which builds superoscillations by linearly combining functions with an ill-conditioned Gram matrix, our method combines orthonormal functions, the Gram matrix of which is obviously the identity. Another feature of the method is that it yields the superoscillatory signal that maximises the energy concentration in a given set, which may or may not include the superoscillatory segment.</P>

Direct Construction of Superoscillations

Dae Gwan Lee,Ferreira, Paulo Jorge S. G. IEEE 2014 IEEE transactions on signal processing Vol.62 No.12

<P>Oscillations of a bandlimited signal at a rate faster than its maximum frequency are called “superoscillations” and have been found useful e.g., in connection with superresolution and superdirectivity. We consider signals of fixed bandwidth and with a finite or infinite number of samples at the Nyquist rate, which are regarded as the adjustable signal parameters. We show that this class of signals can be made to superoscillate by prescribing its values on an arbitrarily fine and possibly nonuniform grid. The superoscillations can be made to occur at a large distance from the nonzero samples of the signal. We give necessary and sufficient conditions for the problem to have a solution, in terms of the nature of the two sets involved in the problem. Since the number of constraints can in general be different from the number of signal parameters, the problem can be exactly determined, underdetermined or overdetermined. We describe the solutions in each of these situations. The connection with oversampling and variational formulations is also discussed.</P>

In-feed organic and inorganic manganese supplementation on broiler performance and physiological responses

de Carvalho, Bruno Reis,Ferreira Junior, Helvio da Cruz,Viana, Gabriel da Silva,Alves, Warley Junior,Muniz, Jorge Cunha Lima,Rostagno, Horacio Santiago,Pettigrew, James Eugene,Hannas, Melissa Izabel Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.11

Objective: A trial was conducted to investigate the effects of supplemental levels of Mn provided by organic and inorganic trace mineral supplements on growth, tissue mineralization, mineral balance, and antioxidant status of growing broiler chicks. Methods: A total of 500 male chicks (8-d-old) were used in 10-day feeding trial, with 10 treatments and 10 replicates of 5 chicks per treatment. A 2×5 factorial design was used where supplemental Mn levels (0, 25, 50, 75, and 100 mg Mn/kg diet) were provided as MnSO₄·H₂O or MnPro. When Mn was supplied as MnPro, supplements of zinc, copper, iron, and selenium were supplied as organic minerals, whereas in MnSO₄·H₂O supplemented diets, inorganic salts were used as sources of other trace minerals. Performance data were fitted to a linearbroken line regression model to estimate the optimal supplemental Mn levels. Results: Manganese supplementation improved body weight, average daily gain (ADG) and feed conversion ratio (FCR) compared with chicks fed diets not supplemented with Mn. Manganese in liver, breast muscle, and tibia were greatest at 50, 75, and 100 mg supplemental Mn/kg diet, respectively. Higher activities of glutathione peroxidase and superoxide dismutase (total-SOD) were found in both liver and breast muscle of chicks fed diets supplemented with inorganic minerals. In chicks fed MnSO₄·H₂O, ADG, FCR, Mn balance, and concentration in liver were optimized at 59.8, 74.3, 20.6, and 43.1 mg supplemental Mn/kg diet, respectively. In MnPro fed chicks, ADG, FCR, Mn balance, and concentration in liver and breast were optimized at 20.6, 38.0, 16.6, 33.5, and 62.3 mg supplemental Mn/kg, respectively. Conclusion: Lower levels of organic Mn were required by growing chicks for performance optimization compared to inorganic Mn. Based on the FCR, the ideal supplemental levels of organic and inorganic Mn in chick feeds were 38.0 and 74.3 mg Mn/kg diet, respectively.

Superoscillations of Prescribed Amplitude and Derivative

Dae Gwan Lee,Ferreira, Paulo Jorge S. G. IEEE 2014 IEEE transactions on signal processing Vol.62 No.13

<P>Superoscillations occur when a bandlimited signal oscillates at a rate higher than its maximum frequency. We show that it is possible to construct superoscillations by constraining not only the value of the signal but also that of its derivative. This allows a better control of the shape of the superoscillations. We find that for any given bandwidth, no matter how small, there exists a unique signal of minimum energy that satisfies any combination of amplitude and derivative constraints, on a sampling grid as fine as desired. We determine the energy of the signal, for any grid, regular or irregular. When the set of derivative constraints is empty the results reduce to minimum energy interpolation. In the absence of amplitude constraints, we obtain pure derivative-constrained extremals. The flexibility gained by having two different types of constraints makes it possible to design superoscillations based only on amplitudes, based only on derivatives, or based on both. In the last case, the amplitude and derivative sampling grids can be interleaved or aligned. We explore this flexibility to build superoscillations that cost less energy. Illustrating examples are given.</P>

Comparison of condylar displacement between three biotypological facial groups by using mounted models and a mandibular position indicator

Maria Joao Ponces,Jose Pedro Tavares,Jorge Dias Lopes,Afonso Pinhao Ferreira 대한치과교정학회 2014 대한치과교정학회지 Vol.44 No.6

Objective: Facial-type?associated variations in diagnostic features have several implications in orthodontics. For example, in hyperdivergent craniofacial types, growth imbalances are compensated by displacement of the condyle. When diagnosis and treatment planning involves centric relation (CR), detailed knowledge of the condylar position is desirable. The present study aimed to measure condylar displacement (CD) between CR and maximum intercuspation in three facial types of an asymptomatic orthodontic population. Methods: The study was conducted in 108 patients classified into three groups of 36 individuals each (27 women and 9 men; mean age, 20.5 years), based on the following facial patterns: hyperdivergent, hypodivergent, and intermediate. To quantify CD along the horizontal and vertical axes, the condylar position was analyzed using mounted casts on a semi-adjustable articulator and a mandibular position indicator. The Student t-test was used to compare CD between the groups. Results: Vertical displacement was found to be significantly different between the hyperdivergent and hypodivergent groups (p < 0.0002) and between the hyperdivergent and intermediate groups (p < 0.0006). The differences in horizontal displacement were not significant between the groups. In each group, vertical CD was more evident than horizontal displacement was. Conclusions: All facial types, especially the hyperdivergent type, carried a significantly high risk of CD. Therefore, the possibility of CD should be carefully evaluated and considered in the assessment of all orthodontic cases in order to accurately assess jaw relationships and avoid possible misdiagnosis.

Effects of Interferon Beta in COVID-19 adult patients: Systematic Review

Juan Pablo Sosa,Maria Mercedes Ferreira Caceres,Jennifer Ross Comptis,Jorge Quiros,Fortunato S Príncipe-Meneses,Riva-Moscoso Adrian,Marie-Pierre Belizaire,Freda Q. Malanyaon,Kuchalambal Agadi,Syeda Sh 대한감염학회 2021 Infection and Chemotherapy Vol.53 No.2

Background: The high rate of transmission and infection of coronavirus disease 2019 (COVID-19) is a public health emergency of major epidemiological concern. No definitive treatments have been established, and vaccinations have only recently begun. We aim to review the efficacy and safety of Interferon Beta (IFN-β) in patients who have a confirmed COVID-19 diagnosis. Materials and Methods: A search from PubMed, Science Direct, Cochrane, and Clinicaltrials. gov databases were conducted from December 2019 to December 2020 to review the efficacy and safety of IFN-β in adult patients with COVID-19 confirmed. We included randomized controlled trials, case reports, and experimental studies. Correspondences, letters, editorials, reviews, commentaries, case control, cross-sectional, and cohort studies that did not include any new clinical data were excluded. Results: Of the 66 searched studies, 8 were included in our review. These studies demonstrated that although IFN-β did not reduce the time to clinical response, there was an increase in discharge rate at day 14 and a decrease in mortality at day 28. The time to negative reverse transcription polymerase chain reaction (RT-PCR) was shown to be significantly shortened in patients receiving IFN-β, along with a lower nasopharyngeal viral load.Further, patients receiving IFN-β had a less significant rise in IL-6. IFN-β was shown to decrease intensive care unit (ICU) admission rate, the requirement of invasive ventilation in severe cases, and improve the survival rate compared to control groups. There were no severe adverse events reported.Our review found that patients who received early treatment with IFN-β experienced significantly reduced length of hospitalization, mortality, ICU admission, and mechanical ventilation. A greater chance of clinical improvement and improved imaging studies was noted in patients who received IFN-β. There were no reported deaths associated with the addition of IFN-β. Further randomized trials involving more significant sample sizes are needed to better understand the effect of IFN-β on survival in COVID-19. Conclusion: This review identified encouraging data and outcomes of incorporating IFN-β to treat COVID-19 patients. IFN-β has been shown to decrease hospital stay's overall length and decrease the severity of respiratory symptoms when added to the standard of care. Also, in some studies, it has been demonstrated to reduce the length of ICU stay, enhance survival rate, and decrease the need for invasive mechanical ventilation. There were minor side effects reported (neuropsychiatric symptoms and hypersensitivity reaction). However, randomized clinical trials with a large sample size are needed to assess IFN-β's benefit precisely.

Effect of acute intradialytic strength physical exercise on oxidative stress and infiammatory responses in hemodialysis patients

( Marta Esgalhado ),( Milena Barcza Stockler-pinto ),( Ludmila Ferreira Medeiros De Franca Cardozo ),( Cinthia Costa ),( Jorge Eduardo Barboza ),( Denise Mafra ) 대한신장학회 2015 Kidney Research and Clinical Practice Vol.34 No.1

Background: Oxidative stress and in.ammation are common .ndings in chronic kidney disease (CKD) patients, and they are directly related to the increased risk of developing cardiovascular disease, which is the major cause of death in these patients, particularly for those undergoing hemodialysis (HD). Strength physical exercise is a new therapeutic approach to reduce these complications in CKD patients. Following this, the purpose of this study was to assess the effect of acute intradialytic strength physical exercise on oxidative stress and in.ammatory responses in HD patients. Methods: Sixteen HD patients were studied (11 women; 44.4714.6 years; body mass index 23.374.9 kg/m2; 61.6743.1 months of dialysis) and served as their own controls. Acute (single session) intradialytic physical exercise were performed at 60% of the onerepetition maximum test for three sets of 10 repetitions for four exercise categories in both lower limbs during 30 minutes. Blood samples were collected on two different days at exactly the same time (30 minutes and 60 minutes after initiating the dialysis-with and without exercise). Antioxidant enzymes activity [superoxide dismutase (SOD), catalase, and glutathione peroxidase], lipid peroxidation marker levels (malondialdehyde), and in.ammatory marker levels (high-sensitivity C-reactive protein) were determined. Results: SOD plasma levels were signi.cantly reduced after acute physical exercise from 244.8740.7 U/mL to 222.4728.9 U/mL (P¼0.03) and, by contrast, increased on the day without exercise (218.2726.5 U/mL to 239.4738.6 U/mL, P¼0.02). There was no alteration in plasma catalase, glutathione peroxidase, malondialdehyde, or highsensitivity C-reactive protein levels in on either day (with or without exercise). Additionally, there was no association between these markers and clinical, anthropometric, or biochemical parameters. Conclusion: These data suggest that acute intradialytic strength physical exercise was unable to reduce oxidative stress and in.ammation, and in addition, it seems to reduce plasma SOD levels, which could exacerbate the oxidative stress in HD patients. Copyright & 2015. The Korean Society of Nephrology. Published by Elsevier. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).