Ricardo Macedo

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AIM To determine the influence of activation method (ultrasound or laser), concentration, pH and exposure time on the reaction rate (RR) of NaOCl when in contact with dentinal walls. METHODOLOGY The walls from standardized root canals in bovine incisors were exposed to a standardized volume of sodium hypochlorite (NaOCl) with different concentrations (2%(More)
AIM To introduce and characterize a reproducible hydrogel as a suitable biofilm mimic in endodontic research. To monitor and visualize the removal of hydrogel from a simulated lateral canal and isthmus for the following: I) Ultrasonic-Activated Irrigation (UAI) with water, ii) UAI with NaOCl and iii) NaOCl without UAI. METHODOLOGY A rheometer was used to(More)
AIM To evaluate the effect of multiple refreshment/activation cycles and temperature on the reaction rate of sodium hypochlorite (NaOCl) with bovine dentine during ultrasonic activated irrigation (UAI) under laboratory conditions. METHODOLOGY The root canal walls of 24 standardized root canals in bovine incisors were exposed to a standardized volume of(More)
INTRODUCTION The aims of this study were to quantify and to visualize the possible occurrence of transient cavitation (bubble formation and implosion) during sonic and ultrasonic (UAI) activated irrigation. METHODS The amount of cavitation generated around several endodontic instruments was measured by sonochemiluminescence dosimetry inside 4 root canal(More)
Ultrasonically Activated Irrigation makes use of an ultrasonically oscillating file in order to improve the cleaning of the root canal during a root canal treatment. Cavitation has been associated with these oscillating files, but the nature and characteristics of the cavitating bubbles were not yet fully elucidated. Using sensitive equipment, the(More)
Keywords: Smart cities Heterogeneous wireless communication Architecture Low cost Interoperability a b s t r a c t Smart cities have become a reality around the world. They rely on wireless communication technologies, and they have provided many benefits to society, such as monitoring road traffic in real-time, giving continuous healthcare assistance to(More)
Ensuring identity management (IdM) systems availability plays a key role to support networked systems. Denial-of-Service (DoS) attacks can make IdM operations unavailable, preventing the use of computational resources by legitimate users. In the literature, the main countermeasures against DoS over IdM systems are based on either the application of external(More)
Under the increasing popularization of portable and mobile devices, as well as the positive trends to the Internet of Everything, Identity Management systems gain a crucial role in integrating different administrative domains towards a global ubiquitous computing. Denial-of-Service (DoS) attacks can make IdM operations unavailable, preventing the use of(More)
Vehicular ad hoc networks (VANETs) are envisioned to support Intelligent Transportation Systems, providing services to drivers. VANETs comprise of vehicles equipped with wireless communication devices, and access points spread over streets and roads. VANETs require multi-hop routing protocols to data tranmission, following two main approaches in relation to(More)
Identity management (IdM) systems employ Identity Providers (IdPs), as guardians of users' critical information. However, Distributed Denial-of-Service (DDoS) attacks can make IdPs operations unavailable, compromising legitimate users. In the literature, the main countermeasures against DDoS attacks are based on either the application of external resources(More)