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A facile strategy for tuning the density of surface-grafted biomolecules for melt extrusion-based additive manufacturing applications

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Bio-Design and Manufacturing 2024年第3期7卷 277-291页

作者： I.A.O.Beeren g.Dos Santos P.J.Dijkstra C.Mota J.Bauer H.Ferreira Rui L.Reis N.neves S.Camarero-Espinosa M.B.Baker L.Moroni Department of Complex Tissue Regeneration MERLN Institute for Technology-Inspired Regenerative MedicineMaastricht University6229 ER MaastrichtThe Netherlands 3B’s Research group I3Bs–Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3B’s-PT government Associate Laboratory 4806-909 Braga/GuimarãesPortugal POLYMAT University of the Basque Country UPV/EHU20018 Donostia/San SebastiánSpain IKERBASQUE Basque Foundation for Science48009 BilbaoSpain

Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering ***,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control cell *** of biomolecules on polymeric surfaces of AM scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface ***,we report a strategy to tune the surface density of bioactive groups by blending a low molecular weight poly(ε-caprolactone)5k(PCL5k)containing orthogonally reactive azide groups with an unfunctionalized high molecular weight PCL75k at different *** porous three-dimensional(3D)scaf-folds were then fabricated using a high weight percentage(75 wt.%)of the low molecular weight PCL *** a proof-of-concept test,we prepared films of three different mass ratios of low and high molecular weight polymers with a thermopress and reacted with an alkynated fluorescent model compound on the surface,yielding a density of 201-561 pmol/cm^(2).Subsequently,a bone morphogenetic protein 2(BMP-2)-derived peptide was grafted onto the films comprising different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal cells(hMSCs)was *** two weeks of culturing in a basic medium,cells expressed higher levels of BMP receptor II(BMPRII)on films with the conjugated *** addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-ing the highest peptide density(i.e.,561 pmol/cm^(2)),indicating the importance of the surface *** together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material ***,we have presented a viable strategy for ME-AM community that desires to tune the bulk and surface functionality via blending of(m

关键词： Additive manufacturing Blending Surface functionalization Surface density Click chemistry Human

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Hyperbolic Conservation Laws on *** Error Estimate for Finite Volume Schemes

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Acta Mathematica Sinica,English Series 2009年第7期25卷 1041-1066页

作者： Philippe g.LeFLOCH Baver OKUTMUSTUR Wladimir neves Laboratoire Jacques-Louis Lions Centre National de la Recherche ScientifiqueUniversité de Paris 6 Instituto de Matemática Universidade Federal do Rio de Janeiro C.P. 68530Cidade Universitária 21945-970

Following Ben-Artzi and LeFloch, we consider nonlinear hyperbolic conservation laws posed on a Riemannian manifold, and we establish an L1-error estimate for a class of finite volume schemes allowing for the approximation of entropy solutions to the initial value problem. The error in the L1 norm is of order h1/4 at most, where h represents the maximal diameter of elements in the family of geodesic triangulations. The proof relies on a suitable generalization of Cockburn, Coquel, and LeFloch＇s theory which was originally developed in the Euclidian setting. We extend the arguments to curved manifolds, by taking into account the effects to the geometry and overcoming several new technical difficulties.

关键词： Hyperbolic conservation law entropy solution finite volume scheme error estimate discrete entropy inequality convergence rate

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Environmental and Durability Perspective of the Use of Curaua Fiber Treated in Mortars

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Journal of Renewable Materials 2022年第9期10卷 2409-2429页

作者： Afonso R.g.de Azevedo Marcelo Nascimento Dirlane do Carmo Markssuel T.Marvila gustavo de C.Xavier Sergio neves Monteiro UENF-State University of the Northern Rio de Janeiro LECIV-Civil Engineering LaboratoryCampos dos GoytacazesBrazil UFF-Federal Fluminense University TER-Department of Agricultural EngineeringNiteróiBrazil UENF-State University of the Northern Rio de Janeiro LAMAV-Advanced Materials LaboratoryCampos dos GoytacazesBrazil IME-Military Institute of Engineering Department of Materials ScienceRio de JaneiroBrazil

The use of natural lignocellulosic fibers(NLFs)as a reinforcement mechanism for cementitious composites,such as mortar,has been investigated in the last ***,their application has often been restricted to technological evaluation research.A NLF with great potential the curaua,which after treatment with NaOH solution,proved to be technologically feasible for mortars reinforcement based on cement and *** objective of this research was the comparative evaluation between a traditional mortar,based on cement and lime,with 1:1:6:0.8 ratio of cement:lime:sand:water,and a modified mortar with addition of 2 wt.%treated curaua fiber in cement mass by evaluating environmental and durability *** a curing time for 28 days,environmental assessments were carried out and durability methodologies were *** tests performed were:(i)attack by chlorides and sulfate,(ii)the wetting and drying cycles,and(iii)slake durability *** results showed that the mortar with the addition of curaua fiber presented a similar behavior to the reference mixture,both in terms of environmental and durability *** modified mortar is able to be used in internal and external environments,the latter with some ***,it also contributes to the promotion of sustainable use of curaua fiber.

关键词： Natural lignocellulosic fibers curaua mortar durability environmental aspects

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Antitumor effects of electrochemical treatment

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Chinese Journal of Cancer Research 2013年第2期25卷 223-234页

作者： Héctor Manuel Camué Ciria Maraelys Morales gonzález Lisset Ortíz Zamora Luis Enrique Bergues Cabrales gustavo Victoriano Sierra gonzález Luciana oliveira de oliveira Rodrigo Zanella Antonio Carlos Buzaid Orlando Parise Luciana Macedo Brito Cesar Augusto Antunes Teixeira Marina das neves gomes gleyce Moreno Venicio Feo da Veiga Marcos Telló Carla Holandino Research Department National Centre of Applied Electromagnetism Oriente University Pharmacy Department Oriente University Finlay Institute La lisa. La Habana Cuba Veterinary Teaching Hospital Federal University of Rio Grande do Sul. Porto Alegre Sírio e Libanês Hospital Faculty of Pharmacy Medicine Department Federal University of Rio de Janeiro Professor Paulo de góes Institute of Microbiology Federal University of Rio de Janeiro Pontifical Catholic University of Rio grande do Sul. Porto Alegre

Electrochemical treatment is an alternative modality for tumor treatment based on the application of a low intensity direct electric current to the tumor tissue through two or more platinum electrodes placed within the tumor zone or in the surrounding areas. This treatment is noted for its great effectiveness, minimal invasiveness and local effect. Several studies have been conducted worldwide to evaluate the anfitumoral effect of this therapy. In all these studies a variety of biochemical and physiological responses of tumors to the applied treatment have been obtained. By this reason, researchers have suggested various mechanisms to explain how direct electric current destroys tumor ceils. Although, it is generally accepted this treatment induces electrolysis, electroosmosis and electroporation in tumoral tissues. However, action mechanism of this alternative modality on the tumor tissue is not well understood. Although the principle of Electrochemical treatment is simple, a standardized method is not yet available. The mechanism by which Electrochemical treatment affects tumor growth and survival may represent more complex process. The present work analyzes the latest and most important research done on the electrochemical treatment of tumors. We conclude with our point of view about the destruction mechanism features of this alternative therapy. Also, we suggest some mechanisms and strategies from the thermodynamic point of view for this therapy. In the area of Electrochemical treatment of cancer this tool has been exploited very little and much work remains to be done. Electrochemical treatment constitutes a good therapeutic option for patients that have failed the conventional oncology methods.

关键词： Direct electric current electrochemical treatment antimmoral treatment tumor tumor electrolysis rumor entropy dissipative structure

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Functional and structural changes in internal pudendal arteries underlie erectile dysfunction induced by androgen deprivation

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Asian Journal of Andrology 2017年第5期19卷 526-532页

作者： Rheure Alves-Lopes Karla B neves Marcondes AB Silva Vania C Olivon Silvia g Ruginsk Jose Antunes-Rodrigues Leandra NZ Ramalho Rita C Tostes Fernando Silva Carneiro Department of Pharmacology Ribeirao Preto Medical School University of Sao Paulo Ribeirao Preto SP Brazil Department of Physics and Chemistry Faculty of Pharmaceutical Sciences of Ribeirao Preto University of Sao Paulo Ribeirao Preto SP Brazil Department of Physiological Sciences Biomedical Sciences InstituteFederal University of Alfenas Alfenas MG Brazil Department of Physiology Ribeirao Preto Medical School University of Sao Paulo Ribeirao Preto SP Brazil Department of Pathology and Legal Medicine Ribeirao Preto Medical School University of Sao Paulo Ribeirao Preto SP Brazil

Androgen deficiency is strongly associated with erectile dysfunction （ED）. Inadequate penile arterial blood flow is one of the major causes of ED. The blood flow to the corpus cavernosum is mainly derived from the internal pudendal arteries （IPAs）; however, no study has evaluated the effects of androgen deprivation on IPA＇s function. We hypothesized that castration impairs IPAs reactivity and structure, contributing to ED. In our study, Wistar male rats, 8-week-old, were castrated and studied 30 days after orchiectomy. Functional and structural properties of rat IPAs were determined using wire and pressure myograph systems, respectively. Protein expression was determined by Western blot and immunohistochemistry. Plasma testosterone levels were determined using the IMMULITE 1000 Immunoassay System. Castrated rats exhibited impaired erectile function, represented by decreased intracavernosal pressure/mean arterial pressure ratio. IPAs from castrated rats exhibited decreased phenylephrine- and electrical field stimulation （EFS）-induced contraction and decreased acetylcholine- and EFS-induced vasodilatation. IPAs from castrated rats exhibited decreased internal diameter, external diameter, thickness of the arterial wall, and cross-sectional area. Castration decreased nNOS and α-actin expression and increased collagen expression, p38 （Thr180/ryr182） phosphorylation, as well as caspase 3 cleavage. In conclusion, androgen deficiency is associated with impairment of IPA reactivity and structure and increased apoptosis signaling markers. Our findings suggest that androgen deficiency-induced vascular dysfunction is an event involving hypotrophic vascular remodeling of IPAs.

关键词： androgen castration internal pudendal artery

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Study of the Firing Temperature of Marajoara Archaeological Ceramics by EPR Associated to INAA Data

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Journal of Environmental Science and Engineering(A) 2012年第9期1卷 1108-1116页

作者： Kelly P. Nunes Casimiro S. Munita Rosimeiri g. Toyota Paulo T.M. oliveira Nilo F. Cano Denise Schaan Oswaldo Baffa Luiz C. oliveira Carlos A. Brunello Eduardo g. neves Ce1ia C. Demartini Nuclear and Energy Research Institute University of Sao Paulo Sao Paulo 5508-000 Brazil Department of Anthropology Basic Campus 1 Federal University of Par6 Beldm 66075-110 Brazil Magnetic Resonance Laboratory Department of Physics University of Sao Paulo Ribeirao Preto 14040-901 Brazil Archaeology and Ethnology Museum Department of Archaeology University of Sao Paulo Sao Paulo 05508-900 Brazil

The Marajó Island is the largest island of the Marajō archipelago, located in the north of Brazil. In this region, at the end of 19th century, it was identified an archaeological society named Marajora, which occupied the island from 400 to 1,350 AD. It was characterized by a ceramic style recognized by its beauty and exuberance. Until this moment, the physical and chemical analysis studies in this ceramics are scarce and this kind of studies may help archaeological studies performed in the island. With this purpose, this work presents a preliminary study of the firing temperature in the ceramics. For that, the elementary concentrations of 109 samples from Museu de Archaeology and Ethnology Museum of the University of Sáo Paulo and samples collected in the Marajá Island were studied. The samples were analyzed using instrumental neutron activation analysis in which the elemental concentration of Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn were determined. The interpretation of the results was made using multivariate statistical approaches and showed the existence of three chemical groups. Some samples of each cluster were chosen for the determination of their firing temperatures by electron paramagnetic resonance, in order to verify if different firing temperatures was associated with different elemental groups of ceramic samples. The results showed that there are no statistical differences in the firing temperature between the samples from Archaeology and Ethnology Museum and the contemporary samples of the Marajá Island.

关键词： Maraj6 island archaeological ceramics INAA EPR multivariate statistical analysis.

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Spatial Analysis with ***: The Pb Jura Lake, Switzerland, Contamination Case

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Journal of geoscience and Environment Protection 2019年第2期7卷 92-113页

作者： Joao Negreiros Ana neves University of Saint Joseph MacaoChina

Protecting groundwater from lead contamination is an important public-health concern and a major national environmental issue worldwide. This article addresses mygeoffice Web Internet service for geographers, in general, and geo-statistics researchers, in particular, with the famous water contamination case at Jura lake, Switzerland (a typical rural-urban region). Based on 189 samples of lead (Pb), five key investigation steps for a scientific perspective of any pollution incident are presented: Descriptive analysis (including nearest neighborhood, g(h) and Kernel techniques), spatial autocorrelation (Moran location scatterplot and Moran I) and Ordinary Kriging (OK) interpolation. The uncertainty and cost assessments issues are exceptionally tackled with Indicator Kriging (including the conditional cumulative distribution function, Shannon local entropy, probabilistic intervals and E-type estimation) and gaussian geo-simulation. The total lead pollution exhibited patterns of high and low levels of concentrations along the all lake, leading to the conclusion that water is unsuitable for human consumption, in general, and unsuitable for any living organism, in particular sub-areas. It is also hoped that future gIS readers will follow this approach for their spatial cases with mygeoffice.

关键词： geographical Information Systems mygeofficec Spatial Autocorrelation Kriging geo-Simulation Costs Analysis

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Evidences of Holocene transgression on Domingos Petrolini Swamp, southern coastal plain, Rio grande do Sul, Brazil

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Journal of geoscientific Research in Northeast Asia 2005年第1期8卷 98-103页

作者： Soraia g.Bauermann Paulo C.P.neves Marleni Marques-Toigo Abdul R.Ashraf Laboratory of Palynology-Lutheran University Canoas/RS CEP 92.420-280Brazil Institute of geosciences Federal University of Rio grande do Sul CEP 91501-970Brazil (in memoriam) Institute of geosciences University of Tuebingen Tuebingen D-72076Germany

The Domingos Petrolini Swamp, located on the Southern Coastal Plain of Rio grande do Sul, near the town of Rio grande, constitutes an ample holocene lagoonal deposit. Events related to the holocene transgression and their diverse phases of glacial-eustatic ocillations were found through palynological analysis. Bases on these palynological data, four distinct phases to the paleoenvironmental evolution of the ecosystem were identified. It has also shown a transgressive restricted marine sequence on the base, which suggests the existence of a coastal brackish lagoon or a marisme type of environment. Later, there was a gradation for continentality conditions along with a scarce pollinical record. The third phase is characterized by the presence of marine components and halophyte vegetation, showing another transgressive event in that place. Lastly, the end of direct marine influence over the swamp was recorded and also the vegetation development as it appears these days.

关键词： paleoenvironmental lagoonal deposits holocen transgression

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Sub-chronic effects of a Phthirusa pyrifolia aqueous extract on reproductive function and comparative hormone levels in male rats

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Asian Pacific Journal of Tropical Biomedicine 2016年第3期6卷 202-210页

作者： Romero Marcos Pedrosa Brandao-Costa Vivianne Ferreira Araujo Elizabeth neves Maria Tereza Santos Correia Ana Lucia Figueiredo Porto Maria das gracas Carneiro-da-Cunha Department of Biochemistry Center of Biological Sciences Federal University of Pernambuco Keizo Asami Laboratory of Imunopathology LIKA/UFPE Department of Anatomy Federal University of Pernambuco Department of Animal Morphology and Physiology Federal Rural University of Pernambuco Keizo Asami Laboratory of Imunopathology LIKA/UFPE

Objective: To explore the effects of aqueous extract from Phthirusa pyrifolia leaves(67 mg/kg body weight for 12 days) on the reproductive function of male Wistar rats through oral ***: Animals(n = 30), aged 13 weeks and weighing(378.5 ± 5.0) g, were housed in a vivarium under controlled environmental conditions [photoperiod of 12 h light/dark,temperature of(23 ± 1)C] and were fed standard rations ad libitum. The experiment ran for 12 days, wherein animals were divided into three groups: negative control(n = 6)received water, positive control(n = 12) with finasteride at a concentration of 1.0 mg/kg;and a test group(n = 12) submitted to aqueous extract. At the end of the experiment, the animals were sacrificed and submitted to ***: The morphological results of the testes showed that the aqueous extract induced significant changes in the diameter and cross-sectional area of the seminiferous tubules as well as the thickness of the seminiferous epithelium. Furthermore, the extract was able to abruptly decrease testosterone concentrations by about 81.88% in the treated group when compared with the negative control,(47.0 ± 4.8) ng/d L and(255.0 ± 2.0) ng/d L,respectively, and 76.8%,(211.0 ± 8.7) ng/d L, when compared with finasteride. However,the extract causes neither liver damage nor impairment of renal ***: These results suggest that the high amounts of flavonoids shown to be in the extract may be responsible for its hepato-protective effects and suggest a possible decrease in the libido and reproduction of rats.

关键词： Reproductive function Phytochemical Testosterone Finasteride Phthirusa pyrifolia

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Factors Associated with Late Diagnosis of Oral Cancer

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International Journal of Clinical Medicine 2015年第2期6卷 105-111页

作者： Jerlucia Cavalcanti das neves Lívia Soraya Toledano Fabiana Moura da Motta Silveira Paulo Sávio Angeiras de góes Postgraduate Program in Dentistry (Collective Health) Faculdade de Odontologia de Pernambuco Universidade de Pernambuco Recife Brazil Faculdade de Odontologia do Recife Recife Brazil Epidemiology and Public Health University of London London UK Department of general and Preventive Dentistry Universidade Federal de Pernambuco Recife Brazil

Objective: The aim of the present study was to determine associations between the late diagnosis of oral cancer and demographic/clinical factors. A quantitative cross-sectional study was carried out in 2007. Material and Method: Oral tumors were recorded based on the TNM staging system, with T1 and T2 considered early diagnosis and T3 and T4 considered late diagnosis. Results: Patient age ranged from 30 to 105 years (mean: 64.7). Just over half of the patients (54.9%) resided in urban areas and approximately 1/4 (25.7%) had an agricultural occupation. The majority had smoking habits (89.9%) and consumed alcohol (62.5%). The most frequent tumor site was the tongue (42.4%), followed by the hard palate (19.2%) and lip (12.2%). The majority (70.1%) were in advanced stages (III and IV). A greater percentage of smokers were in advanced stages than non-smokers. The percentage of cases in the early stages was lowest when the tumor was located in the tongue (14.1%) and highest when located in the buccal mucosa (80.0%). Conclusion: The main causes of the late diagnosis of oral cancer are insufficient training on the part of physicians and dentists in the field of pathology, delays on the part of patients in seeking medical assistance and deficient access to quality medical care, reflecting the absence of preventive public health programs and an effective healthcare system.

关键词： Oral Cancer Late Diagnosis Clinical Stage

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