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A Quasilinear System Related with the Asymptotic Equation of the Nematic Liquid Crystal’s Director Field

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Chinese Annals of Mathematics,Series B 2021年第2期42卷 163-172页

作者： João-paulo DIAS Departamento de Matemática and CMAFcIO Faculdade de Ciências da Universidade de LisboaCampo GrandeEdificio C61749-016 LisboaPortugal

In this paper, the author studies the local existence of strong solutions and their possible blow-up in time for a quasilinear system describing the interaction of a short wave induced by an electron field with a long wave representing an extension of the motion of the director field in a nematic liquid crystal’s asymptotic model introduced in[Saxton, R. A., Dynamic instability of the liquid crystal director. In: Current Progress in Hyperbolic Systems(Lindquist, W. B., ed.), Contemp. Math., Vol.100, Amer. ***., Providence, RI, 1989, pp.325–330] and [Hunter, J. K. and Saxton, R. A., Dynamics of director fields, SIAM J. Appl. Math., 51, 1991, 1498–1521] and studied in [Hunter, J. *** Zheng, Y., On a nonlinear hyperbolic variational equation I, Arch. Rat. Mech. Anal.,129, 1995, 305–353], [Hunter, J. K. and Zheng, Y., On a nonlinear hyperbolic variational equation II, Arch. Rat. Mech. Anal., 129, 1995, 355–383] and in [Zhang, P. and Zheng,Y., On oscillation of an asymptotic equation of a nonlinear variational wave equation,Asymptotic Anal., 18, 1998, 307–327] and, more recently, in [Bressan, A., Zhang, P. and Zheng, Y., Asymptotic variational wave equations, Arch. Rat. Mech. Anal., 183, 2007,163–185].

关键词： Benney system Conservation law Schrödinger equation Nematic liquid crystal Director field

The dynamics of a symmetric coupling of three modified quadratic maps

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Chinese Physics B 2013年第8期22卷 233-237页

作者： paulo C. Rech Departamento de Física Universidade do Estado de Santa Catarina89219-710 Joinville Brazil

We investigate the dynamical behavior of a symmetric linear coupling of three quadratic maps with exponential terms, and identify various interesting features as a function of two control parameters. In particular, we investigate the emergence of quasiperiodic states arising from Naimark-Sacker bifurcations of stable period-l, period-2, and period-3 orbits. We also investigate the multistability in the same coupling. Lyapunov exponents, parameter planes, phase space portraits, and bifurcation diagrams are used to investigate transitions from periodic to quasiperiodic states, from quasiperiodic to mode-locked states and to chaotic states, and from chaotic to hyperchaotic states.

关键词： Naimark-Sacker bifurcation quasiperiodicity chaos hyperchaos

Dynamics in the parameter Space of a Neuron Model

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Chinese Physics Letters 2012年第6期29卷 64-67页

作者： paulo C.Rech Departamento de Fisica Universidade do Estado de Santa Catarina89219-710 JoinvilleBrazil

some two-dimensional parameter-space diagrams are numerically obtained by considering the largest Lyapunov exponent for a four-dimensional thirteen-parameter Hindmarsh-Rose neuron *** different parameter planes are considered,and it is shown that depending on the combination of parameters,a typical scenario can be preserved:for some choice of two parameters,the parameter plane presents a comb-shaped chaotic region embedded in a large periodic *** is also shown that there exist regions close to these comb-shaped chaotic regions,separated by the comb teeth,organizing themselves in period-adding bifurcation cascades.

关键词： parameter chaotic shaped

Application of additively manufactured 3D scaffolds for bone cancer treatment:a review

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Bio-Design and Manufacturing 2022年第3期5卷 556-579页

作者： Yanhao Hou Weiguang Wang paulo Bartolo Department of Mechanical Aerospace and Civil EngineeringSchool of EngineeringFaculty of Science and EngineeringThe University of ManchesterManchester M139PLUK Singapore Center for 3D Printing School of Mechanical and Aerospace EngineeringNanyang Technological UniversitySingaporeSingapore

Bone cancer is a critical health problem on a global scale,and the associated huge clinical and economic burdens are still *** many clinical approaches are currently used for bone cancer treatment,these methods usually affect the normal body functions and thus present significant ***,advanced materials and additive manufacturing have opened up promising avenues for the development of new strategies targeting both bone cancer treatment and post-treatment bone *** paper presents a comprehensive review of bone cancer and its current treatment methods,particularly focusing on a number of advanced strategies such as scaffolds based on advanced functional materials,drug-loaded scaffolds,and scaffolds for photothermal/magnetothermal ***,the main research challenges and future perspectives are elaborated.

关键词： Additive manufacturing Biomanufacturing Bone cancer Implants Tissue engineering

Surgical treatment of Peyronie＇s disease： choosing the best approach to improve patient satisfaction

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Asian Journal of Andrology 2008年第1期10卷 158-166页

作者： paulo H. Egydio Urology Institute Rua lguatemi 192 Cj. 42 Sao Paulo 01451-010 Brazil

Aim： To discuss important points on medical history, preoperative evaluation, real expectations, and selection of the appropriate surgical procedure to improve patient satisfaction after surgical procedures for Peyronie＇s disease. Methods： Recent advances in approaches to Peyronie＇s disease are discussed based on the literature and personal experiences. Issues concerning surgical indication, patient selection, surgical techniques, and grafting are discussed. Lengthening procedures on the convex side of the penile curvature by means of grafting offer the best possible gain from a reconstruction standpoint. Penile rectification and rigidity are required to achieve a completely functional penis. Most patients experience associated erectile dysfunction （ED）, and penile straightening alone may not be enough to restore complete function. Twenty-five patients were submitted to total penile reconstruction on length and girth with concomitant penile prosthesis implant. The maximum length restoration was possible and limited by the length of the dissected neurovascular bundle. The mean age was 55.4 years （32-69 years） and the mean angle of curvature 74.2± 22.4° （0-100°）. Pericardial grafting was used to cover the defect. The mean follow-up time was 11.2 ± 5.9 months （3-22 months）. Results： Mean functional penile length gain was 3.40 ＋ 0.73 cm （2-5 cm）. Penile prosthesis maintained the penis straight. No infections occurred. Sexual intercourse was restored in all patients and all reported recovered self-esteem. Conclusion： Improving patient satisfaction with the surgical treatment includes proper preoperative evaluation on stable disease, penile shortening, vascular and erectile status, patient decision and selection as well as extensive discussion on surgical technique for restoring functional penis （length and rigidity）. Length and girth restoration is very important for self-esteem and patient satisfaction.

关键词： Peyronie's disease erectile dysfunction induratio penis plastica penile induration tunica albuginea surgical technique penis graft surgery penile reconstruction

A novel sampling method for the investigation of gut microbiota

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World Journal of Gastroenterology 2007年第29期13卷 3990-3995页

作者： Alina Guimares Quintanilha Bruno Zilberstein Manoel A A Santos Denis Pajecki Eduardo Guimares Hourneaux Moura paulo roberto Arruda Alves Fauze Maluf-Filho Ivan Cecconello Digestive Surgery Division Department of Gastroenterology and Institute of Biomedical Sciences Department of Microbiology So Paulo University Medical School So Paulo SP Brazil

AIM： In order to characterize the qualitative and quantitative microorganisms in different sites of the lower digestive tract （LDT） in healthy volunteers, a specific technique was developed for collecting mucous of the distal ileum, colon and rectum. METHODS： A polyethylene tube was designed to go through the colonoscope channel with a No. 8 French tube. In order to avoid internal contamination, the distal extremity was protected with a membrane of microfilm after being sterilized in ethilene oxid. To facilitate the aspiration of a precise volume, its interior was coated with silicone. One hundred rnicrolliter （0.1 mL） sample of mucous was collected and transferred into an Eppenddorff tube containing nine hundred rnicrolliter （0.9mL） of VMGA-3 （viable medium of Goteborg）. This procedure was repeated at each site of the LDT with a new sterilized catheter. RESULTS： All sites revealed the ＂non pathogenic＂ anaerobic bacteria Veillonella sp （average 10s colony forming units/mL-CFU/mL）, allowing to conclude an environment of low oxidation-reduction potential （redox） in the LDT. It was also characterized the presence of Klebisiella sp with significant statistical predominance （SSP） in the ileum. Enterobacter sp was found with SSP in the sigrnoid colon, Bacteroides sp non-pigmented （npg） and Ecoli with SSP in the sigrnoid colon and rectum, Enterococcus sp and Lactobacillus sp with SSP in the rectum, all in a mean concentration of 10s CFU/mL CONCLUSION： This procedure is feasible and efficient and can point out a similar distribution of the aerobic and anaerobic bacteria with the presence of biological markers of normal microbiota in the LDT.

关键词： Colony count Microbial Fungi Aerobic bacteria Anaerobic bacteria Gastrointestinal endoscopy Large Intestine Bacterial translocation Microbiology Catheterization

Documental Quality of Websites Concerning Physical Activity, Lifestyle and Sedentarism Available on the Internet

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Health 2019年第12期11卷 1684-1692页

作者： Marcos Bagrichevsky paulo roberto Vasconcellos-Silva Department of Medicine Regional University of Blumenau Blumenau Brazil Federal University of State of Rio de Janeiro Rio de Janeiro Brazil

Objectives: To analyze the documental quality of 389 websites in Portuguese about physical activity, healthy lifestyles and sedentary lifestyles found on the Brazilian version of the general search engine Google. Methods: The documental quality of the 389 websites was estimated based upon the following parameters: 1) a combination of quality criteria from the Health Information Locator (LIS—OPS/BIREME) and those from Chile’s Pontifical Catholic University, organized into 17 variables;2) uniformity of reference criteria (Vancouver);3) association between the presence of authorship and a higher number of the quality criteria being fulfilled. We also studied the ranking of the results presented by Google in addition to attributes connected to the websites’ target audience, the types of content, their sponsors and country of origin. Results: Of the 389 websites studied, 111 links were not active (28.53% CI 95% [24.05 - 33.02]) and none of the websites in the sample met all of the 17 quality variables. Authored websites displayed remarkable differences in quality when compared to those which did not identify their authors. Conclusions: Faced with the issue of the proliferation of websites with questionable quality content, and the fact that the ranking of results interferes directly in the internal evaluation of content relevance, we propose that public-health research institutions cooperate with web-searching developers to improve the website-positioning formula, in which the “identified authorship” criterion should play a major role in the ranking system.

关键词： Health Information Websites Documental Quality Physical Activity

Increased basal plasma brain-derived neurotrophic factor levels in sprint runners

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Neuroscience Bulletin 2011年第5期27卷 325-329页

作者： paulo roberto Correia Fulvio Alexandre Scorza Sérgio Gomes da Silva Aline Pansani Michelle Toscano-Silva Antonio Carlos de Almeida Ricardo Mario Arida 圣保罗联邦大学生理学系圣保罗联邦大学神经内外科系 So Joo del-Rei联邦大学实验与计算神经生物学实验室

Objective Exercise is known to enhance circulating brain-derived neurotrophic factor （BDNF） levels in healthy humans. BDNF changes have been measured in endurance but not in strength exercise. The present study aimed to investigate whether anaerobic activity such as sprinting differentially alters basal plasma BDNF concentration. Methods Brazilian sprinters （100 m） at either the international （Olympics and Outdoor World Championships）（n = 14） or the domestic level （n = 8）, and sedentary subjects （n = 15）, were recruited. Plasma BDNF concentrations were analyzed by enzyme-linked immunosorbent assay. Results The basal plasma BDNF concentrations were significantly higher in the international and the domestic sprinters than in the sedentary subjects. In addition, sprinters at the international level had higher plasma BDNF concentrations than those at the domestic level. Conclusion Our findings suggest that increased basal plasma BDNF level is related to enhanced exercise performance.

关键词： brain-derived neurotrophic factor physical exercise sprint plasma brain human

Spatial-temporal distribution of fatal yellowing in different oil palm genetic materials in eastern amazon

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Information Processing in Agriculture 2022年第3期9卷 365-377页

作者： Bruno Borella Anhe Artur Vinicius Ferreira dos Santos Thiago Alan Ferreira da Silva Lana Leticia Barbosa de Carvalho paulo roberto Silva Farias Universidade Federal Rural da Amazonia Geoestatistics Department66.077-830 BelemBrazil Universidade Federal Rural da Amazonia Entomology Department66.077-830 BelemBrazil

Oil palm (Elaeis guineensis Jacq.) is one of the agricultural crops with the greatest potentialfor vegetable oil production in Brazil. However, a disease of unknown etiology popularlyknown as Fatal Yellowin (FY) has caused damage to Brazilian farmers particularly in theeastern region of the Amazon. so, the objective of this study was to evaluate the spatialdependence of FY on three oil palm genotypes, grown for many years in an organic produc-tion system in the Amazon region. The study area had 4104 ha, divided into 139 plots. Ineach plot, the monthly incidence of disease was monitored forming a database. The num-ber of diseased plants per year, number of accumulated diseased plants, number of dis-eased plants per hectare, growth rate of diseased plants and incidence of accumulateddisease were evaluated. The results indicated spatial distribution of the variables adjustedto the gaussian, spherical and exponential models, with predominance of the first *** increases the purpose that FY is caused by biotic factors. The highest range achievedin the study was 2929 m indicating the susceptibility of the tested genotypes. some plotsclose to the river had the highest incidence of the disease on the study, probably associatedwith higher soil moisture.

关键词： Elaeis guineensis Geostatiscal analysis Kriging Palm oil Spatial dependence