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This research explores the relationship of railroad and the urban dynamics, the genesis of the implantation and the expansion process are investigated. The study uses empirical analysis of reading and interpretation of documentary, iconographic and cartographic sources through observation to explore the urbanization process of the region known as Nova Alta Paulista (extreme west of São Paulo), which emerged along the railway of the Companhia Paulista de Estradas de Ferro (CPEF), a branch of Tronco Oeste. The research reinforces the importance of historical rescue to highlight the impact of regional infrastructure on the urban development.

Cerebral aneurysm is an abnormal dilatation of the blood vessel which affects a high percentage of the worldwide population. One way to investigate this pathology is using in vivo techniques, but these types of experiments have a high cost and low reproducibility. Thus, to understand the local hemodynamics of brain aneurysms, it is imperative to manufacture in vitro models that simulate real brain aneurysms. These biomodels are suitable for experimental testing, as well as for evaluating and validating computational models. In this work, was manufactured a biomodel of a cerebral aneurysm made by polydimethylsiloxane (PDMS), combining rapid prototyping technology with a PDMS gravity casting process. Experimental flow visualizations were performed at different flow rates. The flow visualizations results have shown that there is a transition from laminar to turbulent flow for a flow rate near 6 ml/min. The proposed PDMS biomodels have shown the ability to perform flow visualizations and have the potential to help the development and validation of computational models. The authors acknowledge the financial support provided by Fundação para a Ciência e a Tecnologia (FCT), through the projects EXPL/EME-EME/0732/2021, PTDC/EEI- EEE/2846/2021, funded by NORTE 2020, PORTUGAL2020, and FEDER. This work was also supported by Fundação para a Ciência e a Tecnologia (FCT) under the strategic grants UIDB/04077/2020, UIDB/00690/2020, UIDB/04436/2020 and UIDB/00532/2020. Andrews Souza acknowledges the PhD scholarship 2021.07961.BD attributed by FCT. Partial support from the Junta de Extremadura through Grants No. GR21091 and IB20105 (partially financed by FEDER funds) is gratefully acknowledged. info:eu-repo/semantics/publishedVersion

Polydimethylsiloxane (PDMS) is a polymer that has attracted the attention of researchers due to its unique properties such as transparency, biocompatibility, high flexibility, and physical and chemical stability. In addition, PDMS modification and combination with other materials can expand its range of applications. For instance, the ability to perform superhydrophobic coating allows for the manufacture of lenses. However, many of these processes are complex and expensive. One of the most promising modifications, which consists of the development of an interchangeable coating, capable of changing its optical characteristics according to some stimuli, has been underexplored. Thus, we report an experimental study of the mechanical and optical properties and wettability of pure PDMS and of two PDMS composites with the addition of 1% paraffin or beeswax using a gravity casting process. The composites’ tensile strength and hardness were lower when compared with pure PDMS. However, the contact angle was increased, reaching the highest values when using the paraffin additive. Additionally, these composites have shown interesting results for the spectrophotometry tests, i.e., the material changed its optical characteristics when heated, going from opaque at room temperature to transparent, with transmittance around 75%, at 70 °C. As a result, these materials have great potential for use in smart devices, such as sensors, due to its ability to change its transparency at high temperatures., This research was partially funded by Portuguese national funds of FCT/MCTES (PIDDAC) through the base funding from the following research units: UIDB/00690/2020 (CIMO) and UIDB/04077/2020 (MEtRICs). The authors are also grateful for the funding of FCT through the projects NORTE-01-0145-FEDER-029394, NORTE-01-0145-FEDER-030171, funded by COMPETE2020, NORTE2020, PORTUGAL2020, and FEDER.

Polydimethylsiloxane (PDMS) is one of the most promising elastomers due its remarkable proprieties such as good thermal stability, biocompatibility, corrosion resistance, flexibility, low cost, ease of use, chemically inertia, hyperplastic characteristics, and gas permeability. Thus, it can be used in areas such as microfluidic systems, biomedical devices, electronic components, membranes for filtering and pervaporation, sensors, and coatings. Although pure PDMS has low mechanical properties, such as low modulus of elasticity and strength, it can be improved by mixing the PDMS with other polymers and by adding particles or reinforcements. Fiber-reinforced PDMS has proved to be a good alternative to manufacturing flexible displays, batteries, wearable devices, tactile sensors, and energy harvesting systems. PDMS and particulates are often used in the separation of liquids from wastewater by means of porosity followed by hydrophobicity. Waxes such as beeswax and paraffin have proved to be materials capable of improving properties such as the hydrophobic, corrosion-resistant, thermal, and optical properties of PDMS. Finally, when blended with polymers such as poly (vinyl chloride-co-vinyl acetate), PDMS becomes a highly efficient alternative for membrane separation applications. However, to the best of our knowledge there are few works dedicated to the review and comparison of different PDMS composites. Hence, this review will be focused on PDMS composites, their respective applications, and properties. Generally, the combination of elastomer with fibers, particles, waxes, polymers, and others it will be discussed, with the aim of producing a review that demonstrates the wide applications of this material and how tailored characteristics can be reached for custom applications., This research was partially funded by the Portuguese national funds of FCT/MCTES (PID DAC) through the base funding from the following research units: UIDB/00690/2020 (CIMO), UIDB/04077/2020 (MEtRICs) and UIDB/00532/2020 (CEFT). The authors are also grateful for the fund ing of ANI and CIMO through the projects POCI-01-02B7-FEDER-069844 and CMFPE3- EXPL2021CIMO_01, respectively. The authors also acknowledge partial financial support from the project NORTE-01-0145-FEDER-030171 (PTDC/EMD-EMD/30171/2017) funded by the NORTE 2020 Portugal Regional Operational Programme, under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (FEDER) and by Fundaçao para a Ciencia e Tecnologia (FCT).

There is a continuous search for better and more complete in vitro models with mechanical properties closer to in vivo conditions. In this work a manufacturing process, based on a lost core casting technique, is herein reported to produce aneurysm biomodels to perform experimental hemodynamic studies. By using real artery images combined with a lost core casting technique, three materials were tested: paraffin, beeswax and glycerin-based soap. All in vitro biomodels were compared according to their transparency and final structure. Additionally, comparisons between experimental and numerical flow studies were also performed. The results have shown that the biomodels produced with beeswax and glycerine-based soap were the most suitable in vitro models to perform direct flow visualizations of particulate blood analogue fluids. The biomodels proposed in this works, have the potential to provide further insights into the complex blood flow phenomena happening at different kinds of pathologies and answer to important hemodynamics questions that otherwise cannot be tackled with the existing in vitro models, FCT – Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020, UIDB/04077/2020, UIDB/00690/2020 and NORTE-01-0145-FEDER-030171, funded by COMPETE2020, NORTE 2020, PORTUGAL 2020 and FEDER, R.A and C.F.acknowledge the support of Junta de Extremadura through Grants GR18175 and IB16119 (partially financed by FEDER) This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 798014. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 828835

A pesquisa explora a relação entre a ferrovia e a dinâmica urbana, investiga-se a gênese da implantação e seu processo de expansão regional. O estudo utiliza-se da análise empírica de leitura e interpretação de fontes documentais e cartográficas para explorar o processo de urbanização da região conhecida como Nova Alta Paulista (extremo oeste paulista), que surgiu ao longo da estrada de ferro da Companhia Paulista de Estradas de Ferro (CPEF), ramal do tronco oeste. Até que ponto a infraestrutura ferroviária atuou como elemento estruturante no desenvolvimento urbano dessas cidades. Portanto esta pesquisa tem como objetivo resgatar a formação regional dessas cidades a fim de compreender os seus aspectos morfológicos atuais. Assim, estudar o seu desenvolvimento urbano permite compreender sua relação e como eles interferem no fluxo da sociedade atual. O estudo utiliza-se da análise morfológica para explorar o processo de urbanização das cidades representantes das microrregiões da Nova Alta Paulista (Adamantina, Dracena e Tupã). O recorte da pesquisa reforça a importância do resgate histórico para evidenciar o impacto da infraestrutura regional na formação e no desenvolvimento das cidades.

Cerebral aneurysm is an abnormal dilatation of the blood vessel into a saccular form. They can originate in congenital defects, weakening of the arterial wall with increasing age, atherosclerotic changes, trauma and infectious emboli. The in vivo experiments are an effective way of investigating the appearance, validating new practices and techniques, but beyond ethical issues, these types of experiments are expensive and have low reproducibility. Thus, to better understand the pathophysiological and geometric aspects of an aneurysm, it is important to fabricate in vitro models capable of improving existing endovascular treatments, developing and validating theoretical and computational models. Another difficulty is in the preoperative period of the non-ruptured cerebral aneurysm, known for the success of the skilled acts because there is an anatomical structure of the aneurysm as its current position. Although there are technologies that facilitate three-dimensional video visualization in the case of aneurysms with complex geometries the operative planning is still complicated, so the development of the real three-dimensional physical model becomes advantageous. In this work, the entire process of manufacturing an aneurysm biomodel using polydimethylsiloxane (PDMS) is disassembled by rapid prototyping technology. The manufactured biomodels are able to perform different hemodynamic studies, validate theoretical data, numerical simulations and assist in the preoperative planning. info:eu-repo/semantics/publishedVersion

In last years, some studies have been proved that there is an association between the wall shear stress with intracranial aneurysm rupture, however, is very difficult to understand the mechanical tissue behaviour when subjected to shear stresses. In this work, it is implemented numerical simulations to characterise the polydimethylsiloxane (PDMS) material when it is subjected to a shear solicitation. For this, it was initially necessary to perform some experimental tests to characterize the mechanical behaviour of the material. Based on these results, several numerical simulations were performed with the most common constitutive models in the simulation of hyperelastic materials by varying numerical factors and parameters of the numerical models. info:eu-repo/semantics/publishedVersion

Polydimethylsiloxane (PDMS) is one of the most popular elastomers and has been used in different fields, especially in biomechanics research. Among the many interesting features of this material, its hyperelastic behavior stands out, which allows the use of PDMS in various applications, like the ones that mimic soft tissues. However, the hyperelastic behavior is not linear and needs detailed analysis, especially the characterization of shear strain. In this work, two approaches, numerical and experimental, were proposed to characterize the effect of shear strain on PDMS. The experimental method was implemented as a simple shear testing associated with 3D digital image correlation and was made using two specimens with two thicknesses of PDMS (2 and 4 mm). A finite element software was used to implement the numerical simulations, in which four different simulations using the Mooney&ndash, Rivlin, Yeoh, Gent, and polynomial hyperelastic constitutive models were performed. These approaches showed that the maximum value of shear strain occurred in the central region of the PDMS, and higher values emerged for the 2 mm PDMS thickness. Qualitatively, in the central area of the specimen, the numerical and experimental results have similar behaviors and the values of shear strain are close. For higher values of displacement and thicknesses, the numerical simulation results move further away from experimental values.