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Journal of Civil Engineering and Architecture 2015年第9期9卷 1017-1024页

作者： eliana cristina barreto monteiro Victor Correia de Oliveira Pereira Department of Civil Engineering University of Pernambuco Recife 50720-001 Brazil Department of Civil Engineering Catholic University of Pernambuco Recife 50050 900 Brazil

To examine the protection against reinforcement corrosion due to the combined action of CO2 and chlorides, experimental results of the evaluation of a study with three types of cement are presented. The study was performed observing the behavior of reinforcements which were put in samples submitted to accelerated carbonatation tests and accelerated tests under the effect of chlorides. For the evaluation, intensity corrosion measurements were used using the Pr （polarization resistance） technique, employing these measures as a deterioration indicator. Three types of cement available in the national market were used. The obtained results enabled the classification of the used cements, comparing their profile behaviors in the conditions of the proposed tests.

关键词： Carbonation chlorides corrosion reinforced concrete polarization resistance.

Assessment of the Presence of Chlorides in Mortar through the Silver Nitrate Colorimetric Spraying Method

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Journal of Civil Engineering and Architecture 2015年第6期9卷 677-683页

作者： Victor Correia de Oliveira Pereira eliana cristina barreto monteiro Department of Civil Engineering University of Pernambuco Recife 50720-001 Brazil Department of Civil Engineering Catholic University of Pernambuco Recife 50720-001 Brazil

This study aims to evaluate the presence of free chlorides by the silver nitrate colorimetric spraying method in mortars made with Portland cement CP II Z-32. In order to make an assessment beyond the qualitative analysis, a calculation of the contaminated areas by free chlorides was performed by measuring the regions using a computer image analysis software （IMAGEJ）. The experimental part of the research involved samples of 5 cm x 10 cm of mortar and 0.1 M solution of silver nitrate in distilled water. The mortar samples were made with cement CP II Z-32 with the following concentrations of chloride incorporated into the mixing water： 0%0, 0.4%, 0.6%, 0.8%, 1.0% and 2.0%, in relation to the mass of cement, totaling 108 samples. The average of percentage results from the contaminated area of the series of samples was respectively 0%, 14.9694%, 19.7444%, 46.0239%, 62.3311% and 96.0083% in relation to the total area, concluding that the method of silver nitrate spraying is applicable and that the white color indicates the presence of chloride ions and other possible aggressive salts to the structure or the concrete.

关键词： Silver nitrate chloride ions corrosion colorimetric method.

Evaluation of Reinforced Concrete Structures with Views for Rehabilitation

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Journal of Civil Engineering and Architecture 2016年第1期10卷 72-80页

作者： Jackline de Assis Lopes S. Oliveira Romildo Alves Berenguer Lydia barreto eliana cristina barreto monteiro Romilde Almeida de Oliveira Department of Civil Engineering Catholic University of Pernambuco Recife 51110-200 Brazil Department of Civil Engineering University of Pernambuco Recife 51110-200 Brazil

The increasing number of pathological occurrences is found in reinforced concrete structures, so does the demand for inspection and maintenance services in residential communities in the state of Pernambuco, which aim to detect damage to the structure in a timely manner to minimize repair costs, thus applying preventive maintenance in order to guarantee the estimated useful life of the project for the building. However, it is observed that the practice of periodic inspections is not yet part of the culture of a certain segment of the population that does not have economic means and knowledge of the importance of maintenance to ensure the integrity of the structure. It was used in this work an inspection script with use of tests and methodology to quantify damage and to check the state of degradation of two residential buildings with more than 20 years and built near the seafront where environmental aggression is strong. The deterioration found in each of the buildings has been differentiated due to different corrective maintenance performed at every building. The last maintenance, performed in Building A, was performed by corrective hand of unskilled labour guided by the community itself, which has no expertise in the field of civil engineering. In Building B, the situation is similar, compounded by the opinion of some tenants that there is no need for this routine, even the structure being in critical condition, as was confirmed with the application of the methodology employ. There should be a legislation that governs the execution of inspections and maintenance programs in addition to the existing technical standards. The methodologies presented suitable for checking the degree of degradation of the structures and performed tests confirmed the diagnosis obtained by visual inspection and quantification of damage.

关键词： Pathology inspection maintenance lifespan concrete.

Analysis of a Concrete Structure that Was Exposed to Fires in the Metropolitan Region of Recife

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Journal of Civil Engineering and Architecture 2016年第3期10卷 344-352页

作者： Romildo Alves Berenguer Adauto de Holanda Barbosa eliana cristina barreto monteiro Romilde Almeidade Oliveira Angelo Just da Costa e Silva Department of Civil Engineering Catholic University of Pernambuco Recife 51110-200 Brazil Department of Civil Engineering University of Pernambuco Recife 51110-200 Brazil

In large cities, news about fires in buildings are powered by problems such as old wiring and no maintenance. Accidents with chemicals and human error, which when added to the different characteristics of each fire and structures can generate the factors causing these disasters. The gradual rise in temperature causes a different effect in mortar and concrete parts, verifying the change in coloring provided to loss of mechanical strength and surface crumbling, cracking and disintegration of the structure itself. This paper presents a case study in which a building that is located in the metropolitan region of Recife was exposed to a fire situation. The metropolitan region of Recife is composed of several old buildings that by virtue of their age may have delayed construction methods, and may expose the fragility of the concrete used in its construction on a fire situation. The concrete structures are recognized by the good resistance to fire because of the thermal characteristics of the material, however, the temperature rise in the concrete elements in characteristic causes a reduction in strength and modulus of elasticity of the material, the loss in stiffness leading to polyphase degradation of reinforced concrete, structural parts can lead to ruin, but when properly sized and executed, the concrete can serve as a proactive agent to be exposed to high temperatures, as the same may be subjected to high temperatures accidentally or they may be part of their normal work.

关键词： Awning pathological manifestations durability

Pathological Manifestations on Concrete Bridges at Recife＇s Metropolitan Area

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Journal of Civil Engineering and Architecture 2015年第9期9卷 1060-1068页

作者： Eudes de Arimatéa Rocha Felipe José Salomao de Albuquerque Melo Severino Virgilio Silva eliana cristina barreto monteiro Rafaella Gatis Galvao Department of Civil Engineering University of Pernambuco Recife 50720 001 Brazil Department of Civil Engineering Catholic University of Pernambuco Recife 50050 900 Brazil

Bridges are structures being used to cross rivers, lakes or any other obstacles which involve water. These instruments are commonly used in cities like Recife, which consists of several islands. However, it is common in this city to observe the fast deterioration of these structures that have been built for decades and are subjected to structural recoveries only when they present a possible imminent collapse. The maintenance of these constructions, often used as tourist spots, is essential because of the economic importance, while these structures are responsible for transporting people and cargo, and also play a key role in the city＇s roads. This paper aims to present and assess the conservation status of these bridges through the study of possible pathologies found at Princesa Isabel Bridge, Government Agamenon Bridge, Ponte Giratória Bridge and Paulo Guerra Bridge. The methodology for its inspection will be prescribed by ABNT NBR-9452/86, which provides for ＂Surveys of Concrete Bridges/Viaducts＂. After analysis, it was found that most bridges problems were caused by the presence of moisture that accumulates in bridges due to the absence or malfunction of drainage systems.

关键词： Bridge maintenance pathological manifestations.

Guy Structure with Galvanic Corrosion： Case Study

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Journal of Civil Engineering and Architecture 2016年第7期10卷 792-797页

作者： Romildo Alves Berenguer Edmilson Raimundo de Oliveira Junior Marcus Wagner Pereira da Silva Glauber Beirao de Souza Paulo Helene eliana cristina barreto monteiro Department of Civil Engineering University of Pernambuco Recife 51110-200 Brazil Department of Civil Engineering Catholic University of Pernambuco Reeife 51110-200 Brazil Ph.D.-Engenharia Department of Civil Engineering Street Viscount in Black Gold S6o Paulo 01303-060 Brazil

Reinforcement bar corrosion depends heavily on environment and the processes used. This study will address galvanic corrosion. Based on a case study of galvanic corrosion in a guyed power transmission tower, experiments using a number of methods were made on a small sample of eight poles chosen for excavation and visual inspection, to assess the various resulting diagnoses. Method that provided the best results both in location and classification of the points was adopted, where corrosion had already begun, considering the concern of finding a non-evasive process. To diagnose the status of the poles inserted in rock, after applying the methods, the main types of corrosion affecting them were listed and classified. With the results, the possible means of preventing and maintaining the structure were presented.

关键词： Corrosion diagnosis inspection.

Topical ocular administration of DPP-Ⅳ inhibitors:a new approach for treating diabetes-induced retinal neurodegeneration

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Neural Regeneration Research 2024年第4期19卷 713-714页

作者： Rafael Simó cristina Hernández Diabetes and Metabolism Research Unit Vall d’Hebron Research Institute(VHIR) Department of Medicine Autonomous University of Barcelona Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas(CIBERDEM) Instituto de Salud CarlosⅢ(ICSⅢ)

Retinal neurodegeneration plays a significant role in the pathogenesis of diabetic retinopathy(DR),the leading cause of preventable *** fact,the American Diabetes Association has defined DR as a highly specific neurovascular complication(Solomon et al.,2017).Therefore,it is no longer acceptable to consider DR as merely a microvascular *** this regard,the term diabetic retinal disease(DRD)has been proposed as a broader term comprising microangiopathy and ***,there are currently no treatments available that directly target the neurodegenerative changes of *** paper will give new insights into the translational research in this field with particular emphasis on glucagon-like peptide 1/dipeptidyl peptidase IV(GLP-1/DPP-IV)inhibitors.

关键词： neurodegeneration ocular insight

Circadian rhythm disruption and retinal dysfunction:a bidirectional link in Alzheimer’s disease?

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Neural Regeneration Research 2024年第9期19卷 1967-1972页

作者： Laura Carrero DesireéAntequera cristina Municio Eva Carro Group of Neurodegenerative Diseases Hospital Universitario 12 de Octubre Research Institute(imas12)MadridSpainNetwork Center for Biomedical Research in Neurodegenerative Diseases(CIBERNED)ISCIIIMadridSpain PhD Program in Neuroscience Autonoma de Madrid UniversityMadridSpain Neurobiology of Alzheimer’s Disease Unit Functional Unit for Research into Chronic DiseasesInstituto de Salud Carlos IIIMadridSpainNetwork Centre for Biomedical Research in Neurodegenerative Diseases(CIBERNED)ISCIIIMadridSpain

Dysfunction in circadian rhythms is a common occurrence in patients with Alzheimer’s disease.A predominant function of the retina is circadian synchronization,carrying information to the brain through the retinohypothalamic tract,which projects to the suprachiasmatic ***,Alzheimer’s disease hallmarks,including amyloid-β,are present in the retinas of Alzheimer’s disease patients,followed/associated by structural and functional ***,the mechanistic link between circadian dysfunction and the pathological changes affecting the retina in Alzheimer’s disease is not fully understood,although some studies point to the possibility that retinal dysfunction could be considered an early pathological process that directly modulates the circadian rhythm.

关键词： Alzheimer’s disease amyloid circadian rhythm neurodegeneration retina

Biodegradability of bioplastics in different aquatic environments:A systematic review

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Journal of Environmental Sciences 2024年第8期142卷 169-181页

作者： Maria cristina Lavagnolo Valentina Poli Anna Maria Zampini Valentina Grossule Department of Civil Environmental and Architectural Engineering-Laboratory of Environmental EngineeringUniversity of PadovaLungargine Rovetta 8Padova 35100Italy

Bioplastics were first introduced as environmentally friendly materials,with properties similar to those of conventional plastics.A bioplastic is defined as biodegradable if it can be decomposed into carbon dioxide under aerobic degradation,or methane and CO_(2)under anaerobic conditions,inorganic compounds,and new cellular biomass,by the action of naturally occurring *** definition however does not provide any information on the environmental conditions,timescale and extent at which decomposition processes should *** regard to the aquatic environment,recognized standards have been established to assess the ability of plastics to undergo biodegradation;however,these standards fail to provide clear targets to be met to allow labelling of a bioplastic as ***,these standards grant the user an extensive leeway in the choice of process *** these reasons,the comparison of results deriving from different studies is *** authors analysed and discussed the degree of biodegradability of a series of biodegradable bioplastics in aquatic environments(both fresh and salt water)using the results obtained in the laboratory and from on-site testing in the context of different research *** Oxygen Demand(BOD),CO_(2)evolution,surface erosion and weight loss were the main parameters used by researchers to describe the percentage of *** results showed a large variability both in weight loss and BOD,even when evaluating the same type of *** confirms the need for a reference range of values to be established with regard to parameters applied in defining the biodegradability of bioplastics.

关键词： Biodegradation Bioplastic Plastic Natural environment Plastic waste

Insights on ZEB1-AS1:emerging role from cancer to neurodegeneration

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Neural Regeneration Research 2024年第6期19卷 1187-1188页

作者： Stephana Carelli Federica Rey Erika Maghraby cristina Cereda Pediatric Research Center“Romeo ed Enrica Invernizzi” Department of Biomedical and Clinical SciencesUniversity of MilanMilanItaly Center of Functional Genomics and Rare Diseases Department of PediatricsBuzzi Children’s HospitalMilanItaly Department of Biology and Biotechnology“L.Spallanzani” University of PaviaPaviaItaly

Implications for lncRNAs in the central nervous system:Transcriptional dysregulation is a key contributor to the pathogenesis of a wide range of diseases and long non-coding RNAs(lncRNAs)are highly expressed in the nervous ***,amongst the over 50,000 lncRNAs expressed in the human genome,more than 40%are specifically expressed in the brain where their roles in brain development,neuron functions,maintenance.

关键词： ZEB1 diseases pathogenesis