101 resultados para Rigidez do agregado


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The construction industry is one of the largest consumers of natural raw materials, and concrete is considered today the most used material wide. This accentuated consumption of natural resources has generated concern with the preservation of the environment, and has motivated various studies related to the use of resid ues, which can partially or entirely substitute, with satisfactory performance, some materials such as the aggregate, and in so doing, decrease the impact on the environment caused by the produced residues. Research has been done to better understand and improve the microstructure of concrete, as well as to understand the mechanism of corrosion in reinforced steel. In this context, this work was developed aiming at discovering the influence of the substitution of natural sand by artificial sand, with rega rd to mechanical resistance, microstructure, and durability. To obtain the electrochemical parameters, an adaptation was made to the galvanostatic electrochemical method to study the corrosion in reinforced steel. Concretes of categories 20 MPa and 40 MPa were produced, containing natural sand, and concretes of the same categories were produced with artificial sand substituting the natural sand, and with the addition of sodium nitrate and sodium chloride. Due to the use of rock dust reject (artificial sand), an evaluation was made of its environmental risk. The results indicate that the concretes of category 20 MPa present a better performance than the concrete made with natural sand, thus making it a viable substitute. For the category 40 MPa, the better performance is from the concrete containing natural sand. The adaptation of the galvanostatic electrochemical technique to the study of the corrosion of reinforced steel within concrete proved to be valid for obtaining electrochemical parameters with a high degree of reliability, considering the number of degrees of freedom

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In this study, was used a very promising technique called of pyrolysis, which can be used for obtaining products with higher added value. From oils and residues, since the contribution of heavier oils and residues has intensified to the world refining industry, due to the growing demand for fuel, for example, liquid hydrocarbons in the range of gasoline and diesel. The catalytic pyrolysis of vacuum residues was performed with the use of a mesoporous material belonging the M41S family, which was discovered in the early 90s by researchers Mobil Oil Corporation, allowing new perspectives in the field of catalysis. One of the most important members of this family is the MCM-41, which has a hexagonal arrangement of mesopores with pore diameters between 2 and 10 nm and a high specific surface area, making it very promising for use as a catalyst in petroleum refining for catalytic cracking, and their mesopores facilitate the access of large hydrocarbon molecules. The addition of aluminum in the structure of MCM-41 increases the acidity of the material, making it more positive for application in the petrochemical industry. The mesoporous material of the type Al-MCM41 (ratio Si / Al = 50) was synthesized by hydrothermal method starting from the silica gel, NaOH and distilled water added to the gel pseudobohemita synthesis. Driver was used as structural CTMABr. Removal of organic driver (CTMABr) was observed by TG / DTG and FTIR, but this material was characterized by XRD, which was observed the formation of the main peaks characteristic of mesoporous materials. The analysis of adsorption / desorption of nitrogen this material textural parameters were determined. The vacuum residues (VR's) that are products of the bottom of the vacuum distillation tower used in this study are different from oil fields (regions of Ceará and Rio de Janeiro). Previously characterized by various techniques such as FTIR, viscosity, density, SARA, elemental analysis and thermogravimetry, which was performed by thermal and catalytic degradation of vacuum residues. The effect of AlMCM-41 was satisfactory, since promoted a decrease in certain ranges of temperature required in the process of conversion of hydrocarbons, but also promoted a decrease in energy required in the process. Thus enabling lower costs related to energy expenditure from degradation during processing of the waste

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The Ankylosing Spondylitis (AS) is a chronic inflammatory disease that primarily affects the axial skeleton, leading to limitation of spine mobility and functional disability. Physical therapy, especially exercise, is an important part in your treatment. The Global Postural Reeducation(GPR),a method that uses stretching based on evaluation of muscular chains, with significant interference in postural changes may be a complementary alternative for the treatment of this disease. The aim was to evaluate the effects of Global Postural Reeducation (GPR) in patients with Ankylosing Spondylitis (AS) and compare GPR with group conventional segmental self-stretching and breathing exercises. This is a controlled interventional study of 38 patients divided into 2 groups: a GPR group (n = 22) and a control group (n = 16). Both groups were treated over four months. With the GPR group patients, positions that stretched the shortened muscle chains were used. With the control group patients, conventional segmental self-stretching and breathing exercises were performed. The variables analyzed were: pain intensity, morning stiffness, spine mobility, chest expansion, functional capacity (Health Assessment Questionnaire - Spondyloarthropathies - HAQ-S), quality of life (Medical Outcome Study Short Form 36 Healthy Survey-SF-36), and disease activity (Bath Ankylosing Spondylitis Disease Activity Index - BASDAI). Statistical analysis was used with a significance level of p < 0.05. There was a statistically significant difference for all the parameters analyzed between pre and post-treatment in both groups. In the inter-group comparison the GPR group showed a statistically significant improvement in morning stiffness (p = 0.01), spine mobility parameters, except finger-floor distance (p = 0.11), in chest expansion (p = 0.02), and in the physical aspect component of the SF-36 (p = 0.00).Finally, we observed that this sample of patients with AS ,treatment with RPG 60 seems to have a better response in some clinical measures, than the conventional self stretching performed in groups. Further studies are needed to further evaluate this therapeutic alternative in the EA

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As mucopolissacaridoses (MPS) são doenças genéticas raras decorrente da deficiência de enzimas lisossomais envolvidas no catabolismo de glicosaminoglicanos, resultando em um amplo espectro de manifestações clínicas, progressivas e multissistêmicas, exigindo tratamento por uma equipe multidisciplinar. Embora o Nordeste brasileiro seja uma região com grande taxa de consangüinidade e um efeito fundador envolvendo MPS, não há estudos caracterizando os pacientes dessa região. Nosso objetivo foi determinar o perfil epidemiológico, clínico e genético de casos não publicados com MPS provenientes do Ceará, identificando as diferenças entre outros estudos com MPS e possíveis problemas a serem enfrentados para a realização do diagnóstico precoce. O estudo foi seccional, descritivo, com amostra de pacientes com MPS em acompanhamento no Hospital Infantil Albert Sabin e Hospital Geral Cesar Cals no período de 2006-2013. Os dados foram obtidos a partir da avaliação clínica, revisão de prontuários médicos e entrevista com os pacientes e/ou familiares realizadas pelo investigador principal. Cinquenta e três pacientes foram incluídos no estudo (36 do sexo masculino), sendo 6 MPS I, 17 MPS II, 7 MPS III (3 MPSIII-A, 3 MPS III-B, 1 MPS III-C), 7 MPS IV-A, 16 de MPS VI. O óbito ocorreu em 16 casos (3 MPS I, MPS II 6, 1 MPS IIIA , IIIB 1MPS , 1 MPS IV , 4 MPS VI). A amostra foi composta principalmente por crianças. Houve elevada taxa de consangüinidade e recorrência familiar. Os tipos mais comuns foram MPS II e MPS VI. Exceto para macrossomia em MPS II, os dados de nascimento indicam que não houve risco para desenvolvimento de viii complicações perinatais. Os sintomas iniciaram em crianças com menos de 2 anos. As manifestações clínicas foram heterogêneas exceto para atraso no desenvolvimento neurológico em MPS III e manifestações esqueléticas em MPS IV. As principais características clínicas foram macrocefalia, baixa estatura, alterações odontológicas, respiratórias, cardíacas, hepatoesplenomegalia, hérnia umbilical, rigidez articular e anormalidades esqueléticas. A terapia de reposição enzimática foi instituída em 26 casos (4 MPS I, 10 MPS II, 12 MPS VI). Os problemas sócio-econômicos das famílias, o amplo espectro de sintomas e a gravidade da doença foram causas das dificuldades em realizar a avaliação periódica pela equipe multidisciplinar, além de exames complementares de maior custo para determinar as complicações da doença. Este foi o maior estudo transversal sobre MPS no Nordeste do Brasil. Em contraste com a maior incidência de MPS I na maioria das populações ocidentais, houve maior incidência de MPS II e VI. As alterações respiratórias foram um dos principais contribuintes para a mortalidade precoce, exceto nos casos de MPS I, em que a cardiomiopatia foi prevalente. A menor expectativa de vida ocorreu em MPS I. O envolvimento cognitivo foi comum em casos graves e o maior número de órgãos envolvidos representou maior risco de morrer. Para o diagnóstico precoce, deve-se buscar indivíduos afetados em famílias em que há parentes com MPS, além do maior reconhecimento de sinais e sintomas de MPS por profissionais de saúde

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This study aimed to determine the influence of strength training (ST), in three weekly sessions over ten weeks, on cardiovascular parameters and anthropometric measurements. It is a before and after intervention trial, with a sample composed of 30 individuals. Participants were adults aged between 18 and 40 years, from both sexes and sedentary for at least three months previously. Tests were computed ergospirometry, CRP, PWV and body composition (dependent variables) before and after the experiment. Independent variables, age and sex, were considered in order to determine their influence on the dependent variablesevaluatedend. By comparing the initial cardiovascular parameters with those obtained after intervention in patients undergoing the ST proposed (a Student s t-test was conducted within each group for samples matched to parameters with normal distribution, while the Wilcoxin was applied for those without), there was no significant difference in PWV(p =0469) or PCR(p =0.247), but there was an increase in anaerobic threshold(AT) (p=0.004) and Maximal Oxygen Uptake(VO2max) (p =0.052). In regard to anthropometric measures, individuals significantly reduced their body fat percentage (p<0.001) and fat mass (p<0,001), as well as increasing lean mass (p<0.001). However, no changes were recorded in the waist-to-hip ratio (WHR) (p= 0.777), body mass (p=0.226) or body mass index (BMI) (p =0.212). Findings of this study lead us to believe that the proposed ST, and did not increase the VOP or PCR improves cardiorespiratory capacity and body composition. Devotees of this training can therefore safely enjoy all its benefits without risk to the cardiovascular system

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This research aims to investigate the effectiveness of the legal labor phenomenon in contemporary capitalism as rectifier element of the contradictions between capital and labor. From the analysis of legislative developments - state and business - and court decisions related to the category of freight transport is expected to determine the protectionist stiffness proclaimed by the institutional structure of labor in Brazil, considered by the hegemonic discourse as political-economic factor that prevents growth. It is intended to unravel the relationships between political and civil society, studying the internal contradictions and ideological influence among these spaces, with theoretical support in Marx and Gramsci. The function of this research is to test the premise that the protectionist discourse is a rational action of capitalism and the organic intellectuals of political society in order to achieve hegemony and hide the real contradictions between capital and labor, in addition to also assist in the discussion on deregulation and easing in Brazil. The analysis points to the confirmation of our premise, since the evolution of the legal phenomenon in the transport sector was charging toward the neoliberal project

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This research aims to examine the phenomenon of sexual relations by observing the Social Network Badoo. As a means to achieve this objective, qualitative in-depth interviews were conducted online. The main question is to understand how the amorous expectations in the liquid modernity are configured. Added to that, there is as analysis categories the insight about relationships and the love experiences provided by the use of the Social Network Badoo. There are three initial hypotheses: 1) a time of transition is experienced, in which the liquid love in the proposed terms by Bauman (2004) was gaining ground and, as consequence, the relationships would be presenting themselves shorter, more open and with another interactive proposals for the relations. 2) The consuming practices of the liquid modernity can interpellate the relational practices molding them according to your logic. 3) It is assumed that the reasoning, inherent to the market, of the use followed by the disposal settles itself in the social behavior and this practice is accentuated by technology, through the use of the internet for the establishment of romantic relationships.the empirical analysis shows that both the vision on relationships as the amorous expectations in liquid modernity have as references the model of solid loving relationship, inherent to the traditional modernity. However it also demonstrates that the romantic experiences and practices refer to the liquid relationship model. Therefore, from these statements it is argued that there is in liquid modernity the cohabitation of the liquid and solid models of romantic relationships. In summary, this research aims to understand the contemporary love relationships across the spectrum of relationships that develop on the Internet Social Network: Badoo

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The Oil industry in Brazil has gone through several stages during the economical, political and social historical process. However, the significative changes have happened in the last fifteen years, due to market opening arising from the relaxation of the state monopoly over the Oil deposits and its derivatives. The edition of the Constitutional Amendment #9, changing the first paragraph of the 177th item of the Federal Constitution, marked the end of a stiffness about the monopoly that the Brazilian state kept in relation to the exploration and research of Oil and Gas. The economical order was fundamental to actualize the idea contained in the #9 Amendment, since its contents has the power to set up measures to be adopted by public power in order to organize the economical relations from a social viewpoint. The new brazilian Oil scenery, called pre-salt, presents itself in a way to amaze the economical markets, in addition to creating a new perspective to the social sector. This work will identify, in this new scenario, the need for change in the legal system. Nevertheless, this subject must not be treated in a thoughtless way: being an exhaustible good, we shall not forget that the future generations also must benefit from the exploration of natural resources recently discovered. The settlement of a new regulatory mark, including the change in the concession contract model to production and sharing is one of the suggested solutions as a bill in the National Congress, in an attempt to ensure the sovereignty of the nation. The constitutionality of a new regulatory mark is questioned, starting from an analysis of the state monopoly, grounding the comprehnsions in the brazilian constitutions, the relevance of the creation of Petrobras for self-assertion of the state about the monopoly of Oil and derivatives, and its posture after the Constitutional Amendment nº 9 (1995), when a company stops having control of the state monopoly, beginning to compete in a fairly way with other companies. The market opening and private initiative are emphasized from the viewpoint of the Constitutional Principles of the Economical and Social Order. The relaxation of the monopoly regarding the exploratory activity in the Federal Constitution doesn't deprive from the Union the ownerships of underground goods, enabling to this federal entity to contract, directly or by concession of exploration of goods, to state-owned or private companies. The existing oil in the pre-salt layer transforms the scenario from very high risk to low risk, which gives the Union the possibility of defining another way of exploring this resources in the best interests of the Public Administration

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As an effect of the growing interdependence in international relations, regional integration was conceived to face globalization, with a remarkable influence in politics and law, since the first steps of the European experience. In Latin America, regional integration ideas have blossomed in the 60 s. Among its experiences, MERCOSUL is the one with the most advanced objectives. However, MERCOSUL has not managed to achieve the objectives planned nor moved forward the integration process. Differently of what happened in Europe, in MERCOSUL the common market projected is concluded. It faced many disappointments throughout its brief history. As it matters to law, those were caused by the absence of supranationality, a mechanism that would allow MERCOSUL s decisions to be directly binding in the States with no need of bureaucratic proceedings to incorporate them to national legal systems. Among Latin American States, Brazil is probably the most resistant to integration process, due to Federal Constitution 1988 rigidity and legal professionals conservadorism towards opening legal system to international law. In Brazil hermeneutical standards are always based on national sovereignty and international law is referred as less important. The problems become more visible relating to taxation, a subject that plays an enormous role in integration process for its economic impact, demanding the execution of tax harmonization policies compatible to the integration levels aspired. However, because of the large number of tax rules in the Federal Constitution, structural changes initiatives face difficulties in order to be implemented. Actually, after two Constitutional Reforms on taxation, Brazil has not yet succeeded on promoting the necessary adaptations to regional integration. The research has confirmed the hypothesis that supranationality has indispensably to be adopted if Brazil really desires to move forward the integration process. But it has also been demonstrated that there are hermeneutical paths suitable to the constitutional profile which allow the adoption of supranationality, through the revision of the sovereignty traditional concept

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This research objectify to analyze the effects of minimum wage recovery in the household consumption in the Brazil, northeastern region of the Brazil and the state of the Rio Grande do Norte, in the period of 1995 to 2011. This is because the search for the strengthening of the internal market, via incentive policies to private demand has assumed prominence in the Government agenda. Thus, under the justification of the fierce debate about the effectiveness of countercyclical policies of Brazil, in view of the recent economic crisis, aims to: 1) retake the theoretical debate and, to a certain extent, the evolution of the theory of household consumption, as well as some conclusions about their connection with the minimum wage; 2) to describe the experiences and the effects of this legislation in economic history, with emphasis on the Brazilian case; 3) to present some of the available statistics to research bases, with attention to the specifics of each and the empirical results found for consumption in Brazil; 4) to estimate the effects of minimum wage variation in household consumption in Brazil (BR), northeast (NE) and Rio Grande do Norte (RN). From this, in order to quantify this relationship, makes inferences from the effects of the wage bill and the minimum wage on consumption, in quarterly series (with ad hoc adjustment from the "weights" of each quarter), from classic model of multiple linear regression. The hypothesis is that released: increments in income, derived from the policy of minimum wage recovery will influence directly the household consumption. However, when comparing the results between the units analyzed, the expressiveness of the northeastern families of Brazil and Rio Grande do Norte families front national dynamics with income linked to this floor, drives most significant impacts spending decisions in NE and RN, thus reducing regional disparities in the consumer. The results indicate contrary evidence, because while for the BR a unitary variation in minimum wage increases the consumption in units monetary 1.28, to the NE and RN these parameters are respectively 1.05 and 1.09

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This thesis entitled SINAES: the different faces of the evaluation at UFRN, aims to analyze the configuration that the national policy for assessment in higher education has taken on UFRN. We assume that in recent years there are an oscillation between the concepts of evaluation, according with the logic of public administration it has preferred an approach that presents itself as a promoter of quality, sometimes with regulatory aspects, sometimes with educational ones. The text discusses the use of the new assessment tools for higher education placing them under the new demands on state reform context in which this is to promote and measure quality based on the values of excellence and competitiveness. This movement arises from the redefinition of the role of the State that has been taking features of Evaluator State. From a historical review of government initiatives in the field of evaluation, we analyze the characteristics of assessment policies outlined over the past decades. We are based on the theoretical method that aims to examine the multiple determinants that shape a particular reality from the larger movement of totality. To identify, in this case, connections and ruptures that have emerged over the history of assessment policies aimed at higher education by checking their determinants in order to better explain the reality. To investigate the object of this study we used as instruments: the research literature and research documents, the semi-structured interviews and non-participant observation. The study revealed that there are different practices of evaluation and that before to establishment the SINAES program, the UFRN already had a culture of an institutional assessment, more participatory and democratic, opposing to the rigidity of the self-assessment in SINAES program that it was instituted by the Commission for assessment (CPA). We also noticed that the implementation of the SINAES at URFN has been performed very slowly and the breadth and complexity of the evaluation process has contributed to hinder its implementation in all dimensions provided by MEC. Although it was observed that in its operationalization the SINAES has assumed a more normative assessment and directed to establish rankings between courses and higher education schools than to establish a more qualitative assessment in this system. As regards the evaluation of the undergraduate course studied on this research and subjected to the three dimensions of evaluation proposed by SINAES (self-assessment, Evaluation of Courses and ENADE) it was not possible to verify an effective integration between the methods of assessing conducted. The results are considered separately, in only a partial view of the course evaluated the proposal what pits the SINAES as a system that involves the totality

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The main objective of this thesis was the study of bracing panels of structural masonry, by applying the Finite Element Method and Strut and Tie Method. It was analyzed the following aspects: the effect of orthotropy on the behavior of the panels; distribution of horizontal forces between panels for buildings; comparison between Equivalent Frame and Finite Elements models; panels design with the Strut and Tie Method. The results showed that one should not disregard the orthotropy, otherwise this can lead to models stiffer than the real. Regarding the distribution of horizontal forces, showed that the disregard of lintels and shear deformation leads to significant differences in the simplified model. The results showed also that the models in Finite Element and Equivalent Frame exhibit similar behavior in respect to stiffness of panels and stress distribution over the sessions requested. It was discussing criteria for designing Strut and Tie Method models in one floor panels. Then, the theoretical strength these panels was compared with the rupture strength of panels tested in the literature. The theoretical maximum strength were always less than the rupture strength of the panels obtained in tests, due to the fact that the proposed model cannot represent the behavior of the masonry after the start of the panel cracking due to plasticization of the reinforcement

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Usually masonry structures has low tension strength, hence the design to flexural efforts can results in high reinforcement ratio, specification of high unit and prism strength, structural members with larger section dimensions and modification in structural arrangement to be possible to use masonry members. The main objective of this study is to evaluate the stiffness, the efforts distribution and the effect of horizontal elements (girders) and vertical elements (counterforts) distribution on the behavior of masonry blocks retaining walls. For this purpose, numerical modeling was performed on typical retaining wall arrangements by varying the amount and placement of horizontal and vertical elements, beyond includes elements simulating the reactions of the soil supporting the foundation of the wall. The numerical modeling also include the macro modeling strategy in which the units, mortar and grout are discretized by a standard volume that represents the masonry elastic behavior. Also, numerical model results were compared with those ones of simplified models usually adopted in bending design of masonry elements. The results show horizontal displacements, principal and shear stresses distribution, and bending moments diagrams. From the analysis it was concluded that quantity and manner of distribution of the girders are both important factors to the panel flexural behavior, the inclusion of the foundation changed significantly the behavior of the wall, especially the horizontal displacements, and has been proposed a new way of considering the flanges section of the counterforts

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The construction industry is responsible for generating a lot of waste because of their activities. Consequently, it is noticeable the occurrence of environmental problems in terms of its disposal in inappropriate places. Faced with this problem, some studies have been conducted with the aim of developing technologies and alternatives for recycling construction and demolition waste (CDW), motivated by the scarcity of natural resources and reduction of environmental problems generated. The research aims to characterize the recycled aggregates derived from construction and demolition waste (CDW) produced in the Greater Natal-RN and analyze the performance of mortar coating produced with recycled aggregates. The study includes the chemical , physical and microstructural characterization of recycled aggregates , as well as conducting microscopic analysis and laboratory tests in the fresh state (consistency index , water retention , bulk density and content of entrained air ) and in the hardened state ( compressive strength , tensile strength in bending , water absorption by immersion and capillary , mass density and void ratio ) for mortars produced from different levels of substitution of aggregates ( 0, 20 %, 40 %, 60 %, 80 % and 100 %). The results were satisfactory, providing mortars produced with recycled aggregates, smaller mass density and dynamic modulus values as well as an increase in the rates of absorption and porosity. The tensile strength in bending and compression for TP1 (1:2:8) trait were lower for mortars produced with recycled aggregates and the best result was 20% for replacement. For the TP2 (1:8) mapping, there was an increase in resistance to traction and compression and the best result was for 100% replacement of natural aggregates by recycled. The experiments led to the conclusion that the technical and economic point of view that the mortars produced with recycled aggregates can be used in construction, only if there is an effective control in production processes of recycled aggregate and at the dosage of mortars

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The search for cultural heritage preservation should be a constant, in order to minimize the lost of historical and cultural identity of a country. As part of this cultural heritage, highlights the importance of historical buildings. For the principles of restoration are met its important to know the state of conservation and the existing materials. Given the above, this work aims to study the pathological manifestations of the mortar coating from the Grupo Escolar Augusto Severo. For this, was conducted historical survey of the building, on-site visits with visual observation, collecting samples of mortar coating and characterization through visual and laboratory analysis, XRF, XRD, TG/DTG, OM and SEM-EDS. From the observations, pathological manifestations were found as: cracks, detachment of the coating, dirt, use of inappropriate material basis of cement, efflorescence, mold and mildew and also incompatible material base of cement. It was found that the pathological manifestations were intensified due to lack of coverage in some spots and especially the abandonment of the building, that many years does not have restoration or any other type of preventive and corrective maintenance. The results of laboratory tests indicated that the mortars studied are based on lime, with calcitic nature, and siliceous aggregate, with the presence of clay in two samples. From the samples collected, two are composed of lime, sand and clay and two by lime and sand. In this regard, it is important to conduct periodic inspections and maintenance, as well as carrying out restoration with use of material compatible with the original